Question: There is no relation between Erythromycin use and hypertrophic pyloric stenosis.

Use of macrolides in mother and child and risk of infantile hypertrophic pyloric stenosis: nationwide cohort study
OBJECTIVE To assess the association between use of macrolide antibiotics in mothers and infants from pregnancy onset until 120 days after birth and infantile hypertrophic pyloric stenosis (IHPS). DESIGN Nationwide register based cohort study. SETTING Denmark, 1996-2011. PARTICIPANTS 999,378 liveborn singletons and linked individual level information on macrolide prescriptions (maternal use during pregnancy, n=30,091; maternal use after birth, n=21,557; use in infants, n=6591), surgery for IHPS, and potential confounders. MAIN OUTCOME MEASURES Surgery for IHPS by three categories of macrolide use: in mothers during pregnancy, in mothers after birth, and in infants after birth. RESULTS 880 infants developed IHPS (0.9 cases per 1000 births). Compared with infants with no use of macrolides, the adjusted rate ratio for IHPS in infants with use of macrolides during days 0 to 13 after birth was 29.8 (95% confidence interval 16.4 to 54.1) and during days 14 to 120 was 3.24 (1.20 to 8.74); the corresponding absolute risk differences were 24.4 (95% confidence interval 13.0 to 44.1) and 0.65 (0.06 to 2.21) cases per 1000 infants exposed to macrolides, respectively. The rate ratio for maternal use of macrolides for days 0 to 13 after birth was 3.49 (1.92 to 6.34) and for days 14 to 120 was 0.70 (0.26 to 1.90); the corresponding absolute risk differences were 2.15 (0.82 to 4.64) and -0.11 (-0.26 to 0.31). The rate ratios for maternal use of macrolides during pregnancy were 1.02 (0.65 to 1.59) for weeks 0 to 27 and 1.77 (0.95 to 3.31) for weeks 28 to birth; the corresponding absolute risk differences were 0.01 (-0.31 to 0.50) and 0.67 (-0.06 to 2.02). CONCLUSIONS Treatment of young infants with macrolide antibiotics was strongly associated with IHPS and should therefore only be administered if potential treatment benefits outweigh the risk. Maternal use of macrolides during the first two weeks after birth was also associated with an increased risk of IHPS. A possible association was also found with use during late pregnancy.

A new system for naming ribosomal proteins.
A system for naming ribosomal proteins is described that the authors intend to use in the future. They urge others to adopt it. The objective is to eliminate the confusion caused by the assignment of identical names to ribosomal proteins from different species that are unrelated in structure and function. In the system proposed here, homologous ribosomal proteins are assigned the same name, regardless of species. It is designed so that new names are similar enough to old names to be easily recognized, but are written in a format that unambiguously identifies them as 'new system' names.

Trends in sugar-sweetened beverage consumption among youth and adults in the United States: 1999-2010.
BACKGROUND Reducing sugar-sweetened beverage (SSB) consumption is a recommended strategy to promote optimal health. OBJECTIVE The objective was to describe trends in SSB consumption among youth and adults in the United States. DESIGN We analyzed energy intake from SSBs among 22,367 youth aged 2-19 y and 29,133 adults aged ≥20 y who participated in a 24-h dietary recall as part of NHANES, a nationally representative sample of the US population with a cross-sectional design, between 1999 and 2010. SSBs included soda, fruit drinks, sports and energy drinks, sweetened coffee and tea, and other sweetened beverages. Patterns of SSB consumption, including location of consumption and meal occasion associated with consumption, were also examined. RESULTS In 2009-2010, youth consumed a mean (±SE) of 155 ± 7 kcal/d from SSBs, and adults consumed an age-adjusted mean (±SE) of 151 ± 5 kcal/d from SSBs--a decrease from 1999 to 2000 of 68 kcal/d and 45 kcal/d, respectively (P-trend < 0.001 for each). In 2009-2010, SSBs contributed 8.0% ± 0.4% and 6.9% ± 0.2% of daily energy intake among youth and adults, respectively, which reflected a decrease compared with 1999-2000 (P-trend < 0.001 for both). Decreases in SSB consumption, both in the home and away from home and also with both meals and snacks, occurred over the 12-y study duration (P-trend < 0.01 for each). CONCLUSION A decrease in SSB consumption among youth and adults in the United States was observed between 1999 and 2010.

Pf4-Cre transgenic mice allow the generation of lineage-restricted gene knockouts for studying megakaryocyte and platelet function in vivo.
To generate transgenic mice that express Cre-recombinase exclusively in the megakaryocytic lineage, we modified a mouse bacterial artificial chromosome (BAC) clone by homologous recombination and replaced the first exon of the platelet factor 4 (Pf4), also called CXCL4, with a codon-improved Cre cDNA. Several strains expressing the transgene were obtained and one strain, Q3, was studied in detail. Crossing Q3 mice with the ROSA26-lacZ reporter strain showed that Cre-recombinase activity was confined to megakaryocytes. These results were further verified by crossing the Q3 mice with a strain containing loxP-flanked integrin beta1. Excision of this conditional allele in megakaryocytes was complete at the DNA level, and platelets were virtually devoid of the integrin beta1 protein. The Pf4-Cre transgenic strain will be a valuable tool to study megakaryopoiesis, platelet formation, and platelet function.

Memory CD4+ T cells induce innate responses independently of pathogen
Inflammation induced by recognition of pathogen-associated molecular patterns markedly affects subsequent adaptive responses. We asked whether the adaptive immune system can also affect the character and magnitude of innate inflammatory responses. We found that the response of memory, but not naive, CD4+ T cells enhances production of multiple innate inflammatory cytokines and chemokines (IICs) in the lung and that, during influenza infection, this leads to early control of virus. Memory CD4+ T cell–induced IICs and viral control require cognate antigen recognition and are optimal when memory cells are either T helper type 1 (TH1) or TH17 polarized but are independent of interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) production and do not require activation of conserved pathogen recognition pathways. This represents a previously undescribed mechanism by which memory CD4+ T cells induce an early innate response that enhances immune protection against pathogens.

UV light-induced DNA synthesis arrest in HeLa cells is associated with changes in phosphorylation of human single-stranded DNA-binding protein.
We show that DNA replication activity in extracts of human HeLa cells decreases following UV irradiation. Alterations in replication activity in vitro parallel the UV-induced block in cell cycle progression of these cells in culture. UV irradiation also induces specific changes in the pattern of phosphorylation of the 34 kDa subunit of a DNA replication protein, human single-stranded DNA-binding protein (hSSB). The appearance of a hyperphosphorylated form of hSSB correlates with reduced in vitro DNA replication activity in extracts of UV-irradiated cells. Replication activity can be restored to these extracts in vitro by addition of purified hSSB. These results suggest that UV-induced DNA synthesis arrest may be mediated in part through phosphorylation-related alterations in the activity of hSSB, an essential component of the DNA replication apparatus.

MIRA-seq for DNA methylation analysis of CpG islands
AIM To develop a reliable method for whole genome analysis of DNA methylation. MATERIALS & METHODS Genome-scale analysis of DNA methylation includes affinity-based approaches such as enrichment using methyl-CpG-binding proteins. One of these methods, the methylated-CpG island recovery assay (MIRA), is based on the high affinity of the MBD2b-MBD3L1 complex for CpG-methylated DNA. Here we provide a detailed description of MIRA and combine it with next generation sequencing platforms (MIRA-seq). RESULTS We assessed the performance of MIRA-seq and compared the data with whole genome bisulfite sequencing. CONCLUSION MIRA-seq is a reliable, genome-scale DNA methylation analysis platform for scoring DNA methylation differences at CpG-rich genomic regions. The method is not limited by primer or probe design and is cost effective.

Human SNP Links Differential Outcomes in Inflammatory and Infectious Disease to a FOXO3-Regulated Pathway
The clinical course and eventual outcome, or prognosis, of complex diseases varies enormously between affected individuals. This variability critically determines the impact a disease has on a patient's life but is very poorly understood. Here, we exploit existing genome-wide association study data to gain insight into the role of genetics in prognosis. We identify a noncoding polymorphism in FOXO3A (rs12212067: T > G) at which the minor (G) allele, despite not being associated with disease susceptibility, is associated with a milder course of Crohn's disease and rheumatoid arthritis and with increased risk of severe malaria. Minor allele carriage is shown to limit inflammatory responses in monocytes via a FOXO3-driven pathway, which through TGFβ1 reduces production of proinflammatory cytokines, including TNFα, and increases production of anti-inflammatory cytokines, including IL-10. Thus, we uncover a shared genetic contribution to prognosis in distinct diseases that operates via a FOXO3-driven pathway modulating inflammatory responses.

Periosteum contains skeletal stem cells with high bone regenerative potential controlled by Periostin
Bone regeneration relies on the activation of skeletal stem cells (SSCs) that still remain poorly characterized. Here, we show that periosteum contains SSCs with high bone regenerative potential compared to bone marrow stromal cells/skeletal stem cells (BMSCs) in mice. Although periosteal cells (PCs) and BMSCs are derived from a common embryonic mesenchymal lineage, postnatally PCs exhibit greater clonogenicity, growth and differentiation capacity than BMSCs. During bone repair, PCs can efficiently contribute to cartilage and bone, and integrate long-term after transplantation. Molecular profiling uncovers genes encoding Periostin and other extracellular matrix molecules associated with the enhanced response to injury of PCs. Periostin gene deletion impairs PC functions and fracture consolidation. Periostin-deficient periosteum cannot reconstitute a pool of PCs after injury demonstrating the presence of SSCs within periosteum and the requirement of Periostin in maintaining this pool. Overall our results highlight the importance of analyzing periosteum and PCs to understand bone phenotypes.

Performance of an abbreviated version of the Lubben Social Network Scale among three European community-dwelling older adult populations.
PURPOSE There is a need for valid and reliable short scales that can be used to assess social networks and social supports and to screen for social isolation in older persons. DESIGN AND METHODS The present study is a cross-national and cross-cultural evaluation of the performance of an abbreviated version of the Lubben Social Network Scale (LSNS-6), which was used to screen for social isolation among community-dwelling older adult populations in three European countries. Based on the concept of lack of redundancy of social ties we defined clinical cut-points of the LSNS-6 for identifying persons deemed at risk for social isolation. RESULTS Among all three samples, the LSNS-6 and two subscales (Family and Friends) demonstrated high levels of internal consistency, stable factor structures, and high correlations with criterion variables. The proposed clinical cut-points showed good convergent validity, and classified 20% of the respondents in Hamburg, 11% of those in Solothurn (Switzerland), and 15% of those in London as at risk for social isolation. IMPLICATIONS We conclude that abbreviated scales such as the LSNS-6 should be considered for inclusion in practice protocols of gerontological practitioners. Screening older persons based on the LSNS-6 provides quantitative information on their family and friendship ties, and identifies persons at increased risk for social isolation who might benefit from in-depth assessment and targeted interventions.

Loss of subcellular lipid transport due to ARV1 deficiency disrupts organelle homeostasis and activates the unfolded protein response.
The ARV1-encoded protein mediates sterol transport from the endoplasmic reticulum (ER) to the plasma membrane. Yeast ARV1 mutants accumulate multiple lipids in the ER and are sensitive to pharmacological modulators of both sterol and sphingolipid metabolism. Using fluorescent and electron microscopy, we demonstrate sterol accumulation, subcellular membrane expansion, elevated lipid droplet formation, and vacuolar fragmentation in ARV1 mutants. Motif-based regression analysis of ARV1 deletion transcription profiles indicates activation of Hac1p, an integral component of the unfolded protein response (UPR). Accordingly, we show constitutive splicing of HAC1 transcripts, induction of a UPR reporter, and elevated expression of UPR targets in ARV1 mutants. IRE1, encoding the unfolded protein sensor in the ER lumen, exhibits a lethal genetic interaction with ARV1, indicating a viability requirement for the UPR in cells lacking ARV1. Surprisingly, ARV1 mutants expressing a variant of Ire1p defective in sensing unfolded proteins are viable. Moreover, these strains also exhibit constitutive HAC1 splicing that interacts with DTT-mediated perturbation of protein folding. These data suggest that a component of UPR induction in arv1Δ strains is distinct from protein misfolding. Decreased ARV1 expression in murine macrophages also results in UPR induction, particularly up-regulation of activating transcription factor-4, CHOP (C/EBP homologous protein), and apoptosis. Cholesterol loading or inhibition of cholesterol esterification further elevated CHOP expression in ARV1 knockdown cells. Thus, loss or down-regulation of ARV1 disturbs membrane and lipid homeostasis, resulting in a disruption of ER integrity, one consequence of which is induction of the UPR.

Instruction: Given a scientific claim, retrieve documents that support or refute the claim


Question: There was an estimated 30 million cases of pneumonia in young children worldwide in 2010.

Global and regional burden of hospital admissions for severe acute lower respiratory infections in young children in 2010: a systematic analysis
BACKGROUND The annual number of hospital admissions and in-hospital deaths due to severe acute lower respiratory infections (ALRI) in young children worldwide is unknown. We aimed to estimate the incidence of admissions and deaths for such infections in children younger than 5 years in 2010. METHODS We estimated the incidence of admissions for severe and very severe ALRI in children younger than 5 years, stratified by age and region, with data from a systematic review of studies published between Jan 1, 1990, and March 31, 2012, and from 28 unpublished population-based studies. We applied these incidence estimates to population estimates for 2010, to calculate the global and regional burden in children admitted with severe ALRI in that year. We estimated in-hospital mortality due to severe and very severe ALRI by combining incidence estimates with case fatality ratios from hospital-based studies. FINDINGS We identified 89 eligible studies and estimated that in 2010, 11·9 million (95% CI 10·3-13·9 million) episodes of severe and 3·0 million (2·1-4·2 million) episodes of very severe ALRI resulted in hospital admissions in young children worldwide. Incidence was higher in boys than in girls, the sex disparity being greatest in South Asian studies. On the basis of data from 37 hospital studies reporting case fatality ratios for severe ALRI, we estimated that roughly 265,000 (95% CI 160,000-450,000) in-hospital deaths took place in young children, with 99% of these deaths in developing countries. Therefore, the data suggest that although 62% of children with severe ALRI are treated in hospitals, 81% of deaths happen outside hospitals. INTERPRETATION Severe ALRI is a substantial burden on health services worldwide and a major cause of hospital referral and admission in young children. Improved hospital access and reduced inequities, such as those related to sex and rural status, could substantially decrease mortality related to such infection. Community-based management of severe disease could be an important complementary strategy to reduce pneumonia mortality and health inequities. FUNDING WHO.

Cytochemistry and C-values: the less-well-known world of nuclear DNA amounts.
BACKGROUND In the plant sciences there are two widely applied technologies for measuring nuclear DNA content: Feulgen absorbance cytophotometry and flow cytometry (FCM). While FCM is, with good reasons, increasingly popular among plant scientists, absorbance-cytophotometric techniques lose ground. This results in a narrowing of the methodological repertoire, which is neither desirable nor beneficial. Both approaches have their advantages, but static cytophotometry seems to pose more instrumental difficulties and material-based problems than FCM, so that Feulgen-based data in the literature are often less reliable than one would expect. SCOPE The purpose of this article is to present a selective overview of the field of nuclear DNA content measurement, and C-values in particular, with a focus on the technical difficulties imposed by the characteristics of the biological material and with some comments on the photometrical aspects of the work. For over 20 years it has been known that plant polyphenols cause problems in Feulgen DNA cytophotometry, since they act as major staining inhibitors leading to unreliable results. However, little information is available about the chemical classes of plant metabolites capable of DNA staining interference and the mechanisms of their inhibition. Plant slimes are another source of concern. CONCLUSIONS In FCM research to uncover the effects of secondary metabolites on measurement results has begun only recently. In particular, the analysis of intraspecific genome size variation demands a stringent methodology which accounts for inhibitors. FCM tests for inhibitory effects of endogenous metabolites should become obligatory. The use of dry seeds for harvesting embryo and endosperm nuclei for FCM and Feulgen densitometry may often provide a means of circumventing staining inhibitors. The importance of internal standardization is highlighted. Our goal is a better understanding of phytochemical/cytochemical interactions in plant DNA photometry for the benefit of an ever-growing list of plant genome sizes.

Computational and Statistical Analyses of Amino Acid Usage and Physico-Chemical Properties of the Twelve Late Embryogenesis Abundant Protein Classes
Late Embryogenesis Abundant Proteins (LEAPs) are ubiquitous proteins expected to play major roles in desiccation tolerance. Little is known about their structure - function relationships because of the scarcity of 3-D structures for LEAPs. The previous building of LEAPdb, a database dedicated to LEAPs from plants and other organisms, led to the classification of 710 LEAPs into 12 non-overlapping classes with distinct properties. Using this resource, numerous physico-chemical properties of LEAPs and amino acid usage by LEAPs have been computed and statistically analyzed, revealing distinctive features for each class. This unprecedented analysis allowed a rigorous characterization of the 12 LEAP classes, which differed also in multiple structural and physico-chemical features. Although most LEAPs can be predicted as intrinsically disordered proteins, the analysis indicates that LEAP class 7 (PF03168) and probably LEAP class 11 (PF04927) are natively folded proteins. This study thus provides a detailed description of the structural properties of this protein family opening the path toward further LEAP structure - function analysis. Finally, since each LEAP class can be clearly characterized by a unique set of physico-chemical properties, this will allow development of software to predict proteins as LEAPs.

Centrosome aberrations: cause or consequence of cancer progression?
Many human tumours show centrosome aberrations, indicating an underlying deregulation of centrosome structure, duplication or segregation. Centrosomes organize microtubule arrays throughout the cell cycle, thereby influencing both tissue architecture and the accuracy of chromosome segregation. But what are the origins of centrosomal abnormalities in tumours, and what impact do they have on the generation of invasive, genetically unbalanced cells during cancer progression?

BMP/SMAD1 signaling sets a threshold for the left/right pathway in lateral plate mesoderm and limits availability of SMAD4.
Bistability in developmental pathways refers to the generation of binary outputs from graded or noisy inputs. Signaling thresholds are critical for bistability. Specification of the left/right (LR) axis in vertebrate embryos involves bistable expression of transforming growth factor beta (TGFbeta) member NODAL in the left lateral plate mesoderm (LPM) controlled by feed-forward and feedback loops. Here we provide evidence that bone morphogenetic protein (BMP)/SMAD1 signaling sets a repressive threshold in the LPM essential for the integrity of LR signaling. Conditional deletion of Smad1 in the LPM led to precocious and bilateral pathway activation. NODAL expression from both the left and right sides of the node contributed to bilateral activation, indicating sensitivity of mutant LPM to noisy input from the LR system. In vitro, BMP signaling inhibited NODAL pathway activation and formation of its downstream SMAD2/4-FOXH1 transcriptional complex. Activity was restored by overexpression of SMAD4 and in embryos, elevated SMAD4 in the right LPM robustly activated LR gene expression, an effect reversed by superactivated BMP signaling. We conclude that BMP/SMAD1 signaling sets a bilateral, repressive threshold for NODAL-dependent Nodal activation in LPM, limiting availability of SMAD4. This repressive threshold is essential for bistable output of the LR system.

A model for the role of gut bacteria in the development of autoimmunity for type 1 diabetes
Several lines of evidence suggest a role for the gut microbiome in type 1 diabetes. Treating diabetes-prone rodents with probiotics or antibiotics prevents the development of the disorder. Diabetes-prone rodents also have a distinctly different gut microbiome compared with healthy rodents. Recent studies in children with a high genetic risk for type 1 diabetes demonstrate significant differences in the gut microbiome between children who develop autoimmunity for the disease and those who remain healthy. However, the differences in microbiome composition between autoimmune and healthy children are not consistent across all studies because of the strong environmental influences on microbiome composition, particularly diet and geography. Controlling confounding factors of microbiome composition uncovers bacterial associations with disease. For example, in a human cohort from a single Finnish city where geography is confined, a strong association between one dominant bacterial species, Bacteroides dorei, and type 1 diabetes was discovered (Davis-Richardson et al. Front Microbiol 2014;5:678). Beyond this, recent DNA methylation analyses suggest that a thorough epigenetic analysis of the gut microbiome may be warranted. These studies suggest a testable model whereby a diet high in fat and gluten and low in resistant starch may be the primary driver of gut dysbiosis. This dysbiosis may cause a lack of butyrate production by gut bacteria, which, in turn, leads to the development of a permeable gut followed by autoimmunity. The bacterial community responsible for these changes in butyrate production may vary around the world, but bacteria of the genus Bacteroides are thought to play a key role.

The structure of the follistatin:activin complex reveals antagonism of both type I and type II receptor binding.
TGF-beta ligands stimulate diverse cellular differentiation and growth responses by signaling through type I and II receptors. Ligand antagonists, such as follistatin, block signaling and are essential regulators of physiological responses. Here we report the structure of activin A, a TGF-beta ligand, bound to the high-affinity antagonist follistatin. Two follistatin molecules encircle activin, neutralizing the ligand by burying one-third of its residues and its receptor binding sites. Previous studies have suggested that type I receptor binding would not be blocked by follistatin, but the crystal structure reveals that the follistatin N-terminal domain has an unexpected fold that mimics a universal type I receptor motif and occupies this receptor binding site. The formation of follistatin:BMP:type I receptor complexes can be explained by the stoichiometric and geometric arrangement of the activin:follistatin complex. The mode of ligand binding by follistatin has important implications for its ability to neutralize homo- and heterodimeric ligands of this growth factor family.

Bruce treadmill test in children: normal values in a clinic population.
The Bruce treadmill protocol is suitable for children as young as age 4 years. Maximal endurance time may be used as the sole criterion of exercise capacity, and normal values were established with 327 children having an innocent heart murmur. Mean endurance time in boys increased from 10.4 minutes at age 4 to 5 years, to 14.1 minutes at age 13 to 15 years. Mean endurance time in girls increased from 9.5 minutes at age 4 to 5 years to 12.3 minutes at age 10 to 12 years. Mean maximal heart rate ranged from 193 to 206 beats/min. Age differences in mean maximal and submaximal heart rates were small. There were negative correlations between endurance time and the ratio of weight to height. There were negative correlations between heart rates at treadmill stages 1 to 3 and the endurance times. The correlation coefficient of endurance time with maximal oxygen uptake was 0.88, but for clinical purposes endurance time alone is a satisfactory indicator of exercise performance.

Cancer Cell Membrane-Coated Nanoparticles for Anticancer Vaccination and Drug Delivery
Cell-derived nanoparticles have been garnering increased attention due to their ability to mimic many of the natural properties displayed by their source cells. This top-down engineering approach can be applied toward the development of novel therapeutic strategies owing to the unique interactions enabled through the retention of complex antigenic information. Herein, we report on the biological functionalization of polymeric nanoparticles with a layer of membrane coating derived from cancer cells. The resulting core-shell nanostructures, which carry the full array of cancer cell membrane antigens, offer a robust platform with applicability toward multiple modes of anticancer therapy. We demonstrate that by coupling the particles with an immunological adjuvant, the resulting formulation can be used to promote a tumor-specific immune response for use in vaccine applications. Moreover, we show that by taking advantage of the inherent homotypic binding phenomenon frequently observed among tumor cells the membrane functionalization allows for a unique cancer targeting strategy that can be utilized for drug delivery applications.

Prepregnancy BMI and the risk of gestational diabetes: a systematic review of the literature with meta-analysis.
The objective of this study is to assess and quantify the risk for gestational diabetes mellitus (GDM) according to prepregnancy maternal body mass index (BMI). The design is a systematic review of observational studies published in the last 30 years. Four electronic databases were searched for publications (1977-2007). BMI was elected as the only measure of obesity, and all diagnostic criteria for GDM were accepted. Studies with selective screening for GDM were excluded. There were no language restrictions. The methodological quality of primary studies was assessed. Some 1745 citations were screened, and 70 studies (two unpublished) involving 671 945 women were included (59 cohorts and 11 case-controls). Most studies were of high or medium quality. Compared with women with a normal BMI, the unadjusted pooled odds ratio (OR) of an underweight woman developing GDM was 0.75 (95% confidence interval [CI] 0.69 to 0.82). The OR for overweight, moderately obese and morbidly obese women were 1.97 (95% CI 1.77 to 2.19), 3.01 (95% CI 2.34 to 3.87) and 5.55 (95% CI 4.27 to 7.21) respectively. For every 1 kg m(-2) increase in BMI, the prevalence of GDM increased by 0.92% (95% CI 0.73 to 1.10). The risk of GDM is positively associated with prepregnancy BMI. This information is important when counselling women planning a pregnancy.

Relationship of soft drink consumption to global overweight, obesity, and diabetes: a cross-national analysis of 75 countries.
OBJECTIVES We estimated the relationship between soft drink consumption and obesity and diabetes worldwide. METHODS We used multivariate linear regression to estimate the association between soft drink consumption and overweight, obesity, and diabetes prevalence in 75 countries, controlling for other foods (cereals, meats, fruits and vegetables, oils, and total calories), income, urbanization, and aging. Data were obtained from the Euromonitor Global Market Information Database, the World Health Organization, and the International Diabetes Federation. Bottled water consumption, which increased with per-capita income in parallel to soft drink consumption, served as a natural control group. RESULTS Soft drink consumption increased globally from 9.5 gallons per person per year in 1997 to 11.4 gallons in 2010. A 1% rise in soft drink consumption was associated with an additional 4.8 overweight adults per 100 (adjusted B; 95% confidence interval [CI] = 3.1, 6.5), 2.3 obese adults per 100 (95% CI = 1.1, 3.5), and 0.3 adults with diabetes per 100 (95% CI = 0.1, 0.8). These findings remained robust in low- and middle-income countries. CONCLUSIONS Soft drink consumption is significantly linked to overweight, obesity, and diabetes worldwide, including in low- and middle-income countries.

Instruction: Given a scientific claim, retrieve documents that support or refute the claim


Question: Thiopurine active metabolites can be catabolized through dephosphorylation of thioguanine nucleotides.

Activating mutations in the NT5C2 nucleotidase gene drive chemotherapy resistance in relapsed ALL
Acute lymphoblastic leukemia (ALL) is an aggressive hematological tumor resulting from the malignant transformation of lymphoid progenitors. Despite intensive chemotherapy, 20% of pediatric patients and over 50% of adult patients with ALL do not achieve a complete remission or relapse after intensified chemotherapy, making disease relapse and resistance to therapy the most substantial challenge in the treatment of this disease. Using whole-exome sequencing, we identify mutations in the cytosolic 5'-nucleotidase II gene (NT5C2), which encodes a 5'-nucleotidase enzyme that is responsible for the inactivation of nucleoside-analog chemotherapy drugs, in 20/103 (19%) relapse T cell ALLs and 1/35 (3%) relapse B-precursor ALLs. NT5C2 mutant proteins show increased nucleotidase activity in vitro and conferred resistance to chemotherapy with 6-mercaptopurine and 6-thioguanine when expressed in ALL lymphoblasts. These results support a prominent role for activating mutations in NT5C2 and increased nucleoside-analog metabolism in disease progression and chemotherapy resistance in ALL.

Summary
The genetic diseases Hutchinson-Gilford progeria syndrome (HGPS) and restrictive dermopathy (RD) arise from accumulation of farnesylated prelamin A because of defects in the lamin A maturation pathway. Both of these diseases exhibit symptoms that can be viewed as accelerated aging. The mechanism by which accumulation of farnesylated prelamin A leads to these accelerated aging phenotypes is not understood. Here we present evidence that in HGPS and RD fibroblasts, DNA damage checkpoints are persistently activated because of the compromise in genomic integrity. Inactivation of checkpoint kinases Ataxia-telangiectasia-mutated (ATM) and ATR (ATM- and Rad3-related) in these patient cells can partially overcome their early replication arrest. Treatment of patient cells with a protein farnesyltransferase inhibitor (FTI) did not result in reduction of DNA double-strand breaks and damage checkpoint signaling, although the treatment significantly reversed the aberrant shape of their nuclei. This suggests that DNA damage accumulation and aberrant nuclear morphology are independent phenotypes arising from prelamin A accumulation in these progeroid syndromes. Since DNA damage accumulation is an important contributor to the symptoms of HGPS, our results call into question the possibility of treatment of HGPS with FTIs alone.

Function and regulation of SUMO proteases
Covalent attachment of small ubiquitin-like modifier (SUMO) to proteins is highly dynamic, and both SUMO–protein conjugation and cleavage can be regulated. Protein desumoylation is carried out by SUMO proteases, which control cellular mechanisms ranging from transcription and cell division to ribosome biogenesis. Recent advances include the discovery of two novel classes of SUMO proteases, insights regarding SUMO protease specificity, and revelations of previously unappreciated SUMO protease functions in several key cellular pathways. These developments, together with new connections between SUMO proteases and the recently discovered SUMO-targeted ubiquitin ligases (STUbLs), make this an exciting period to study these enzymes.

Radiation and Dual Checkpoint Blockade Activates Non-Redundant Immune Mechanisms in Cancer
Immune checkpoint inhibitors result in impressive clinical responses, but optimal results will require combination with each other and other therapies. This raises fundamental questions about mechanisms of non-redundancy and resistance. Here we report major tumour regressions in a subset of patients with metastatic melanoma treated with an anti-CTLA4 antibody (anti-CTLA4) and radiation, and reproduced this effect in mouse models. Although combined treatment improved responses in irradiated and unirradiated tumours, resistance was common. Unbiased analyses of mice revealed that resistance was due to upregulation of PD-L1 on melanoma cells and associated with T-cell exhaustion. Accordingly, optimal response in melanoma and other cancer types requires radiation, anti-CTLA4 and anti-PD-L1/PD-1. Anti-CTLA4 predominantly inhibits T-regulatory cells (Treg cells), thereby increasing the CD8 T-cell to Treg (CD8/Treg) ratio. Radiation enhances the diversity of the T-cell receptor (TCR) repertoire of intratumoral T cells. Together, anti-CTLA4 promotes expansion of T cells, while radiation shapes the TCR repertoire of the expanded peripheral clones. Addition of PD-L1 blockade reverses T-cell exhaustion to mitigate depression in the CD8/Treg ratio and further encourages oligoclonal T-cell expansion. Similarly to results from mice, patients on our clinical trial with melanoma showing high PD-L1 did not respond to radiation plus anti-CTLA4, demonstrated persistent T-cell exhaustion, and rapidly progressed. Thus, PD-L1 on melanoma cells allows tumours to escape anti-CTLA4-based therapy, and the combination of radiation, anti-CTLA4 and anti-PD-L1 promotes response and immunity through distinct mechanisms.

Generating an iPSC bank for HLA-matched tissue transplantation based on known donor and recipient HLA types.
The likelihood for immunological rejection of Human Leukocyte Antigens (HLA)-mismatched induced pluripotent stem cells (iPSCs) limits their therapeutic potential. Here we show how a tissue bank from 150 selected homozygous HLA-typed volunteers could match 93% of the UK population with a minimal requirement for immunosuppression. Our model provides a practical approach for using existing HLA-typed samples to generate an iPSC stem cell bank that circumvents prospective typing of a large number of individuals.

The fallacy of the ecological fallacy: the potential misuse of a concept and the consequences.
Ecological studies have been evaluated in epidemiological contexts in terms of the "ecological fallacy. " Although the empirical evidence for a lack of comparability between correlations derived from ecological- and individual-level analyses is compelling, the conceptual meaning of the ecological fallacy remains problematic. This paper argues that issues in cross-level inference can be usefully conceptualized as validity problems, problems not peculiar to ecological-level analyses. Such an approach increases the recognition of both potential inference problems in individual-level studies and the unique contributions of ecological variables. This, in turn, expands the terrain for the location of causes for disease and interventions to improve the public's health.

Membrane estrogen receptor-α levels in MCF-7 breast cancer cells predict cAMP and proliferation responses
17β-estradiol (E2) can rapidly induce cAMP production, but the conditions under which these cAMP levels are best measured and the signaling pathways responsible for the consequent proliferative effects on breast cancer cells are not fully understood. To help resolve these issues, we compared cAMP mechanistic responses in MCF-7 cell lines selected for low (mERlow) and high (mERhigh) expression of the membrane form of estrogen receptor (mER)-α, and thus addressed the receptor subform involved in cAMP signaling. MCF-7 cells were immunopanned and subsequently separated by fluorescence activated cell sorting into mERhigh (mER-α-enriched) and mERlow (mER-α-depleted) populations. Unique (compared with previously reported) incubation conditions at 4°C were found to be optimal for demonstrating E2-induced cAMP production. Time-dependent and dose-dependent effects of E2 on cAMP production were determined for both cell subpopulations. The effects of forskolin, 8-CPT cAMP, protein kinase A inhibitor (H-89), and adenylyl cyclase inhibitor (SQ 22,536) on E2-induced cell proliferation were assessed using the crystal violet assay. We demonstrated a rapid and transient cAMP increase after 1 pmol/l E2 stimulation in mERhigh cells; at 4°C these responses were much more reliable and robust than at 37°C (the condition most often used). The loss of cAMP at 37°C was not due to export. 3-Isobutyl-1-methylxanthine (IBMX; 1 mmol/l) only partially preserved cAMP, suggesting that multiple phosphodiesterases modulate its level. The accumulated cAMP was consistently much higher in mERhigh cells than in mERlow cells, implicating mER-α levels in the process. ICI172,780 blocked the E2-induced response and 17α-estradiol did not elicit the response, also suggesting activity through an estrogen receptor. E2 dose-dependent cAMP production, although biphasic in both cell types, was responsive to 50-fold higher E2 concentrations in mERhigh cells. Proliferation of mERlow cells was stimulated over the whole range of E2concentrations, whereas the number of mERhigh cells was greatly decreased at concentrations above 1 nmol/l, suggesting that estrogen over-stimulation can lead to cell death, as has previously been reported, and that mER-α participates. E2-mediated activation of adenylyl cyclase and downstream participation of protein kinase A were shown to be involved in these responses. Rapid mER-α-mediated nongenomic signaling cascades generate cAMP and downstream signaling events, which contribute to the regulation of breast cancer cell number.

DEVELOPMENT AND VALIDATION OF A MEASURE OF EMOTIONAL INTELLIGENCE
This series of studies describes the development of a measure of emotional intelligence based on the model of emotional intelligence developed by Salovey and Mayer [Salovey, P. & Mayer, J. D. (1990). Emotional intelligence. Imagination, Cognition and Personality, 9, 185–211.]. A pool of 62 items represented the different dimensions of the model. A factor analysis of the responses of 346 participants suggested the creation of a 33-item scale. Additional studies showed the 33-item measure to have good internal consistency and testretest reliability. Validation studies showed that scores on the 33-item measure  1. (a) correlated with eight of nine theoretically related constructs, including alexithymia, attention to feelings, clarity of feelings, mood repair, optimism and impulse control;    2.  (b) predicted first-year college grades;    3. (c) were significantly higher for therapists than for therapy clients or for prisoners;    4.  (d) were significantly higher for females than males, consistent with prior findings in studies of emotional skills;    5. (e) were not related to cognitive ability and    6. (f) were associated with the openness to experience trait of the big five personality dimensions.

E2F-6: a novel member of the E2F family is an inhibitor of E2F-dependent transcription
The E2F family of transcription factors are essential for the regulation of genes required for appropriate progression through the cell cycle. Five members of the E2F family have been previously reported, namely E2F1-5. All five are key elements in transcriptional regulation of essential genes, and they can be divided into two functional groups, those that induce S-phase progression when overexpressed in quiescent cells (E2Fs 1–3), and those that do not (E2Fs 4–5). Here, we describe the identification of a novel member of this family, which we refer to as E2F-6. E2F-6 shares significant homology with E2Fs 1–5, especially within the DNA binding, heterodimerization and marked box domains. Unlike E2Fs 1–5, E2F-6 lacks a transactivation and a pocket protein binding domain, hence, forms a unique third group within the E2F family. E2F-6 is a nuclear protein that can form heterodimers with the DP proteins (both DP-1 and DP-2) in vitro and in vivo. Our results show that the complex formed between E2F-6 and the DP proteins, possesses high DNA binding activity, displaying a preference for a TTTCCCGC E2F recognition site, which is slightly different to the E2F consensus site derived from the E2 promoter (TTTCGCGC). In contrast to the other members of the E2F family, ectopic expression of E2F-6 inhibits transcription from promoters possessing E2F recognition sites rather than activating transcription. In addition, overexpression of E2F-6 suppresses the transactivational effects of co-expression of E2F-1 and DP-1. The inhibitory effect of E2F-6 is dependent on its DNA binding activity and its ability to form heterodimers with the DPs. Interestingly, ectopic expression of E2F-6 leads to accumulation of cells in S-phase. Our data suggest that E2F-6 expression delays the exit from S-phase rather than inducing S-phase, which further emphasizes the functional difference between E2F-6 and the previously known E2F family members.

Cardiovascular effects of intensive lifestyle intervention in type 2 diabetes.
BACKGROUND Weight loss is recommended for overweight or obese patients with type 2 diabetes on the basis of short-term studies, but long-term effects on cardiovascular disease remain unknown. We examined whether an intensive lifestyle intervention for weight loss would decrease cardiovascular morbidity and mortality among such patients. METHODS In 16 study centers in the United States, we randomly assigned 5145 overweight or obese patients with type 2 diabetes to participate in an intensive lifestyle intervention that promoted weight loss through decreased caloric intake and increased physical activity (intervention group) or to receive diabetes support and education (control group). The primary outcome was a composite of death from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for angina during a maximum follow-up of 13.5 years. RESULTS The trial was stopped early on the basis of a futility analysis when the median follow-up was 9.6 years. Weight loss was greater in the intervention group than in the control group throughout the study (8.6% vs. 0.7% at 1 year; 6.0% vs. 3.5% at study end). The intensive lifestyle intervention also produced greater reductions in glycated hemoglobin and greater initial improvements in fitness and all cardiovascular risk factors, except for low-density-lipoprotein cholesterol levels. The primary outcome occurred in 403 patients in the intervention group and in 418 in the control group (1.83 and 1.92 events per 100 person-years, respectively; hazard ratio in the intervention group, 0.95; 95% confidence interval, 0.83 to 1.09; P=0.51). CONCLUSIONS An intensive lifestyle intervention focusing on weight loss did not reduce the rate of cardiovascular events in overweight or obese adults with type 2 diabetes. (Funded by the National Institutes of Health and others; Look AHEAD ClinicalTrials.gov number, NCT00017953.).

The DNA polymerase λ is required for the repair of non-compatible DNA double strand breaks by NHEJ in mammalian cells
DNA polymerase lambda (polλ) is a recently identified DNA polymerase whose cellular function remains elusive. Here we show, that polλ participates at the molecular level in a chromosomal context, in the repair of DNA double strand breaks (DSB) via non-homologous end joining (NHEJ) in mammalian cells. The expression of a catalytically inactive form of polλ (polλDN) decreases the frequency of NHEJ events in response to I-Sce-I-induced DSB whereas inactivated forms of its homologues polβ and polμ do not. Only events requiring DNA end processing before ligation are affected; this defect is associated with large deletions arising in the vicinity of the induced DSB. Furthermore, polλDN-expressing cells exhibit increased sensitization and genomic instability in response to ionizing radiation similar to that of NHEJ-defective cells. Our data support a requirement for polλ in repairing a subset of DSB in genomic DNA, thereby contributing to the maintenance of genetic stability mediated by the NHEJ pathway.

Instruction: Given a scientific claim, retrieve documents that support or refute the claim


Question: Tirasemtiv has no effect on cardiac muscle.

Activation of fast skeletal muscle troponin as a potential therapeutic approach for treating neuromuscular diseases
Limited neural input results in muscle weakness in neuromuscular disease because of a reduction in the density of muscle innervation, the rate of neuromuscular junction activation or the efficiency of synaptic transmission. We developed a small-molecule fast-skeletal-troponin activator, CK-2017357, as a means to increase muscle strength by amplifying the response of muscle when neural input is otherwise diminished secondary to neuromuscular disease. Binding selectively to the fast-skeletal-troponin complex, CK-2017357 slows the rate of calcium release from troponin C and sensitizes muscle to calcium. As a consequence, the force-calcium relationship of muscle fibers shifts leftwards, as does the force-frequency relationship of a nerve-muscle pair, so that CK-2017357 increases the production of muscle force in situ at sub-maximal nerve stimulation rates. Notably, we show that sensitization of the fast-skeletal-troponin complex to calcium improves muscle force and grip strength immediately after administration of single doses of CK-2017357 in a model of the neuromuscular disease myasthenia gravis. Troponin activation may provide a new therapeutic approach to improve physical activity in diseases where neuromuscular function is compromised.

Preoperative statin treatment reduces systemic inflammatory response and myocardial damage in cardiac surgery.
OBJECTIVE To determine if preoperative statin treatment is associated with a reduction in systemic inflammatory response (SIR) and myocardial damage markers following cardiac surgery with cardiopulmonary bypass (CPB). METHODS We study a prospective cohort of 138 patients who underwent coronary and valvular surgery with CPB. We differentiate two study groups: patients with (group A, n=72) or without (group B, n=66) statins. Plasma levels of pro-inflammatory interleukins (tumour necrosis factor-alpha (TNF-alpha), interleukin (IL)-6, IL-8 and IL-2R), creatine phosphokinase (CPK), CPK-MB and troponin I were measured before and 1, 6, 24 and >72 h after surgery. RESULTS The baseline, operative and postoperative morbidity and mortality characteristics were similar for both the groups. Group A had significantly lower postoperative levels of IL-6 than group B at 6h (68.8+/-5 pg ml(-1) vs 108.9+/-108 pg ml(-1), p=0.01), 24h (71.7+/-7 pg ml(-1) vs 110.4+/-106 pg ml(-1), p=0.01) and before hospital discharge (21.6+/-12 pg ml(-1) vs 32.8+/-27 pg ml(-1), p=0.005), as well as significantly lower average IL-6 levels in the first 24h following surgery (71.8+/-5 pgml(-1) vs 112.8+/-82 pg ml(-1), p=0.002). The postoperative CPK-MB at 24h (19.7+/-23 ng ml(-1) vs 33.1+/-32 ng ml(-1), p=0.02) and troponin I levels at the end of the intervention (2.2+/-2.2 ng ml(-1) vs 3.3+/-3.1 ng ml(-1), p=0.03) and at 24h (4.1+/-3.5 ng ml(-1) vs 6.6+/-8 ng ml(-1), p=0.04) were also significantly lower in the group treated with statins prior to surgery. CONCLUSIONS Preoperative treatment with statins is associated with a lower biochemical parameters of SIR and myocardial damage following cardiac surgery with CPB, regardless of it being coronary bypass grafting (CABG) or valvular surgery.

The role of protein clearance mechanisms in organismal ageing and age-related diseases.
The ability to maintain a functional proteome, or proteostasis, declines during the ageing process. Damaged and misfolded proteins accumulate with age, impairing cell function and tissue homeostasis. The accumulation of damaged proteins contributes to multiple age-related diseases such as Alzheimer's, Parkinson's or Huntington's disease. Damaged proteins are degraded by the ubiquitin-proteasome system or through autophagy-lysosome, key components of the proteostasis network. Modulation of either proteasome activity or autophagic-lysosomal potential extends lifespan and protects organisms from symptoms associated with proteostasis disorders, suggesting that protein clearance mechanisms are directly linked to ageing and age-associated diseases.

CD4+CD25+Foxp3+Regulatory T Cells Protect Endothelial Function Impaired by Oxidized Low Density Lipoprotein via the KLF-2 Transcription Factor
Objective: To investigate the regulation of CD4+CD25+ Regulatory T cells (Tregs) on pro-inflammatory adhesion molecules, Krüppel-Like Factor-2 (KLF-2) and its downstream transcriptional targets in human umbilical vein endothelial cells (HUVECs) impaired by ox-LDL and the mechanisms of it. Methods and results: HUVECs were cultured in the continuous presence of ox-LDL(0 mg/L,25 mg/L,50 mg/L,100 mg/L) for 4, 6, 12 and 24 hours to allow identification of early-and late-induced genes, respectively, whereas non-stimulated controls were taken at 0 hours. The expression of pro-inflammatory adhesion molecules such as vascular cell adhesion molecule-1 (VCAM-1), intracellular adhesion molecule-1 (ICAM-1), E-selectin, KLF-2 and its target genes eNOS, PAI-1 were determined by real time RT-PCR and/or western-blot analysis. Expression of pro-inflammatory adhesion molecules, KLF-2, eNOS and PAI-1 in HUVEC cultured alone or with anti-CD3 mAbs activated Tregs, followed by addition of ox-LDL (50 mg/L) for 6 hours, are compared to expression levels in control cultures. Ox-LDL treated HUVECs increased pro-inflammatory adhesion molecules expression, as well as increased PAI-1 but decreased eNOS expression accompanied with significant downregulating of KLF-2 at a dose and time dependent manner. Furthermore, ox-LDL increased pro-inflammatory adhesion molecules but inhibited KLF2 expression was reversed by addition of Tregs. Small interfering RNA reduced endogenous KLF-2 expression and partly reversed the suppressive effect of Tregs on HUVECs activation, which strongly implicate KLF-2 as a transcriptional regulator of the Tregs-mediated effects in endothelial cells. Mechanism studies reveal that Treg-mediated KLF2 expression in HUVECs impaired by ox-LDL requires cell contact as well as soluble factors. Conclusions: Tregs could protect endothelial function that is largely dependent on KLF2 and its downstream transcriptional targets regulation involving cell-to-cell contact and soluble factors.

Rapid purification of homodimer and heterodimer HIV-1 reverse transcriptase by metal chelate affinity chromatography.
We have modified an Escherichia coli vector expressing 66-kDa HIV-1 reverse transcriptase (p66) so that it simultaneously expresses this and the pol-coded protease. The twin expression cassette yields high quantities of both reverse transcriptase and protease; however, under these conditions, 50% of the over-expressed p66 reverse transcriptase is processed, resulting in accumulation of large quantities of p66/p51 enzyme. Furthermore, addition of a poly(histidine) affinity label at the amino terminus of the reverse-transcriptase-coding sequence (His-p66) permits a simple, rapid purification of milligram quantities of either p66 or p66/p51 enzyme from a crude lysate by metal chelate affinity chromatography. Purified His-p66 and His-p66/His-p51 reverse transcriptase exhibit both reverse transcriptase and RNase H activity. Purification by metal chelate chromatography of a p66/p51 enzyme wherein only the p66 component is labelled strengthens the argument for the existence of a heterodimer.

Snail coordinately regulates downstream pathways to control multiple aspects of mammalian neural precursor development.
The Snail transcription factor plays a key role in regulating diverse developmental processes but is not thought to play a role in mammalian neural precursors. Here, we have examined radial glial precursor cells of the embryonic murine cortex and demonstrate that Snail regulates their survival, self-renewal, and differentiation into intermediate progenitors and neurons via two distinct and separable target pathways. First, Snail promotes cell survival by antagonizing a p53-dependent death pathway because coincident p53 knockdown rescues survival deficits caused by Snail knockdown. Second, we show that the cell cycle phosphatase Cdc25b is regulated by Snail in radial precursors and that Cdc25b coexpression is sufficient to rescue the decreased radial precursor proliferation and differentiation observed upon Snail knockdown. Thus, Snail acts via p53 and Cdc25b to coordinately regulate multiple aspects of mammalian embryonic neural precursor biology.

Management of chronic tension-type headache with tricyclic antidepressant medication, stress management therapy, and their combination: a randomized controlled trial.
CONTEXT Chronic tension-type headaches are characterized by near-daily headaches and often are difficult to manage in primary practice. Behavioral and pharmacological therapies each appear modestly effective, but data are lacking on their separate and combined effects. OBJECTIVE To evaluate the clinical efficacy of behavioral and pharmacological therapies, singly and combined, for chronic tension-type headaches. DESIGN AND SETTING Randomized placebo-controlled trial conducted from August 1995 to January 1998 at 2 outpatient sites in Ohio. PARTICIPANTS Two hundred three adults (mean age, 37 years; 76% women) with diagnosis of chronic tension-type headaches (mean, 26 headache d/mo). INTERVENTIONS Participants were randomly assigned to receive tricyclic antidepressant (amitriptyline hydrochloride, up to 100 mg/d, or nortriptyline hydrochloride, up to 75 mg/d) medication (n = 53), placebo (n = 48), stress management (eg, relaxation, cognitive coping) therapy (3 sessions and 2 telephone contacts) plus placebo (n = 49), or stress management therapy plus antidepressant medication (n = 53). MAIN OUTCOME MEASURES Monthly headache index scores calculated as the mean of pain ratings (0-10 scale) recorded by participants in a daily diary 4 times per day; number of days per month with at least moderate pain (pain rating >/=5), analgesic medication use, and Headache Disability Inventory scores, compared by intervention group. RESULTS Tricyclic antidepressant medication and stress management therapy each produced larger reductions in headache activity, analgesic medication use, and headache-related disability than placebo, but antidepressant medication yielded more rapid improvements in headache activity. Combined therapy was more likely to produce clinically significant (>/=50%) reductions in headache index scores (64% of participants) than antidepressant medication (38% of participants; P =.006), stress management therapy (35%; P =.003), or placebo (29%; P =.001). On other measures the combined therapy and its 2 component therapies produced similar outcomes. CONCLUSIONS Our results indicate that antidepressant medication and stress management therapy are each modestly effective in treating chronic tension-type headaches. Combined therapy may improve outcome relative to monotherapy.

Phase locking and multiple oscillating attractors for the coupled mammalian clock and cell cycle.
Daily synchronous rhythms of cell division at the tissue or organism level are observed in many species and suggest that the circadian clock and cell cycle oscillators are coupled. For mammals, despite known mechanistic interactions, the effect of such coupling on clock and cell cycle progression, and hence its biological relevance, is not understood. In particular, we do not know how the temporal organization of cell division at the single-cell level produces this daily rhythm at the tissue level. Here we use multispectral imaging of single live cells, computational methods, and mathematical modeling to address this question in proliferating mouse fibroblasts. We show that in unsynchronized cells the cell cycle and circadian clock robustly phase lock each other in a 1:1 fashion so that in an expanding cell population the two oscillators oscillate in a synchronized way with a common frequency. Dexamethasone-induced synchronization reveals additional clock states. As well as the low-period phase-locked state there are distinct coexisting states with a significantly higher period clock. Cells transition to these states after dexamethasone synchronization. The temporal coordination of cell division by phase locking to the clock at a single-cell level has significant implications because disordered circadian function is increasingly being linked to the pathogenesis of many diseases, including cancer.

Green synthesis of silver nanoparticles and characterization of their inhibitory effects on AGEs formation using biophysical techniques
Advanced glycation end-products (AGEs) resulting from non-enzymatic glycation are one of the major factors implicated in secondary complications of diabetes. Scientists are focusing on discovering new compounds that may be used as potential AGEs inhibitors without affecting the normal structure and function of biomolecules. A number of natural and synthetic compounds have been proposed as AGE inhibitors. In this study, we investigated the inhibitory effects of AgNPs (silver nanoparticles) in AGEs formation. AgNPs (~30.5 nm) synthesized from Aloe Vera leaf extract were characterized using UV-Vis spectroscopy, energy-dispersive X-ray spectroscopy (EDX), high resolution-transmission electron microscopy, X-ray diffraction and dynamic light scattering (DLS) techniques. The inhibitory effects of AgNPs on AGEs formation were evaluated by investigating the degree of reactivity of free amino groups (lysine and arginine residues), protein-bound carbonyl and carboxymethyl lysine (CML) content, and the effects on protein structure using various physicochemical techniques. The results showed that AgNPs significantly inhibit AGEs formation in a concentration dependent manner and that AgNPs have a positive effect on protein structure. These findings strongly suggest that AgNPs may play a therapeutic role in diabetes-related complications.

P446L-importin-beta inhibits nuclear envelope assembly by sequestering nuclear envelope assembly factors to the microtubules.
The P446L mutant Drosophila importin-beta (P446L-imp-beta) has been reported to prohibit--in dominant negative fashion--nuclear envelope (NE) assembly. Along elucidating the mode of action of P446L-imp-beta we studied in vitro NE assembly on Sepharose beads. While Drosophila embryo extracts support NE assembly over Sepharose beads coated with Ran, NE assembly does not take place in extracts supplied with exogenous P446L-imp-beta. A NE also forms over importin-beta-coated beads. Surprisingly, when immobilized to Sepharose beads P446L-imp-beta as efficiently recruits NE vesicles as normal importin-beta. The discrepancy in behavior of cytoplasmic and bead-bound P446L-imp-beta appears to be related to icreased--as compared to normal importin-beta--microtubule (MT) binding ability of P446L-imp-beta. While wild-type importin-beta is able to bind MTs and the binding decreases upon RanGTP interaction, P446L-imp-beta cannot be removed from the MTs by RanGTP. P446L-imp-beta, like normal importin-beta, binds some types of the nucleoporins that have been known to be required for NE assembly at the end of mitosis. It appears that the inhibitory effect of P446L-imp-beta on NE assembly is caused by sequestering some of the nucleoporins required for NE assembly to the MTs.

A single RNA-dependent RNA polymerase assembles with mutually exclusive nucleotidyl transferase subunits to direct different pathways of small RNA biogenesis.
Members of the conserved family of eukaryotic RNA-dependent RNA polymerases (Rdrs) synthesize double-stranded RNA (dsRNA) intermediates in diverse pathways of small RNA (sRNA) biogenesis and RNA-mediated silencing. Rdr-dependent pathways of sRNA production are poorly characterized relative to Rdr-independent pathways, and the Rdr enzymes themselves are poorly characterized relative to their viral RNA-dependent RNA polymerase counterparts. We previously described a physical and functional coupling of the Tetrahymena thermophila Rdr, Rdr1, and a Dicer enzyme, Dcr2, in the production of approximately 24-nucleotide (nt) sRNA in vitro. Here we characterize the endogenous complexes that harbor Rdr1, termed RDRCs. Distinct RDRCs assemble to contain Rdr1 and subsets of the total of four tightly Rdr1-associated proteins. Of particular interest are two RDRC subunits, Rdn1 and Rdn2, which possess noncanonical ribonucleotidyl transferase motifs. We show that the two Rdn proteins are uridine-specific polymerases of separate RDRCs. Two additional RDRC subunits, Rdf1 and Rdf2, are present only in RDRCs containing Rdn1. Rdr1 catalytic activity is retained in RDRCs purified from cell extracts lacking any of the nonessential RDRC subunits (Rdn2, Rdf1, Rdf2) or if the RDRC harbors a catalytically inactive Rdn. However, specific disruption of each RDRC imposes distinct loss-of-function consequences at the cellular level and has a differential impact on the accumulation of specific 23-24-nt sRNA sequences in vivo. The biochemical and biological phenotypes of RDRC subunit disruption reveal a previously unanticipated complexity of Rdr-dependent sRNA biogenesis in vivo.

Instruction: Given a scientific claim, retrieve documents that support or refute the claim


Question: Tirasemtiv targets cardiac muscle.

Activation of fast skeletal muscle troponin as a potential therapeutic approach for treating neuromuscular diseases
Limited neural input results in muscle weakness in neuromuscular disease because of a reduction in the density of muscle innervation, the rate of neuromuscular junction activation or the efficiency of synaptic transmission. We developed a small-molecule fast-skeletal-troponin activator, CK-2017357, as a means to increase muscle strength by amplifying the response of muscle when neural input is otherwise diminished secondary to neuromuscular disease. Binding selectively to the fast-skeletal-troponin complex, CK-2017357 slows the rate of calcium release from troponin C and sensitizes muscle to calcium. As a consequence, the force-calcium relationship of muscle fibers shifts leftwards, as does the force-frequency relationship of a nerve-muscle pair, so that CK-2017357 increases the production of muscle force in situ at sub-maximal nerve stimulation rates. Notably, we show that sensitization of the fast-skeletal-troponin complex to calcium improves muscle force and grip strength immediately after administration of single doses of CK-2017357 in a model of the neuromuscular disease myasthenia gravis. Troponin activation may provide a new therapeutic approach to improve physical activity in diseases where neuromuscular function is compromised.

Prediagnostic levels of C-peptide, IGF-I, IGFBP -1, -2 and -3 and risk of endometrial cancer.
Conditions related to chronic hyperinsulinemia, such as obesity, noninsulin dependent diabetes mellitus and polycystic ovary syndrome, are associated with an increased risk of endometrial cancer. Elevated plasma IGF-I and decreased levels of IGF-binding proteins have been shown to be associated with increased risk of several cancer types that are frequent in affluent societies. We investigated for the first time in a prospective study the association of pre-diagnostic blood concentrations of C-peptide (a marker of pancreatic insulin production), IGF-I, IGFBP-1, -2 and -3 with endometrial cancer risk. A case-control study was nested within 3 cohorts in New York (USA), Umeå (Sweden) and Milan (Italy). It included 166 women with primary invasive endometrial cancer and 315 matched controls, of which 44 case and 78 control subjects were premenopausal at recruitment. Endometrial cancer risk increased with increasing levels of C-peptide (ptrend = 0.0002), up to an odds ratio (OR) of 4.76 [95% confidence interval (CI) = 1.91-11.8] for the highest quintile. This association remained after adjustment for BMI and other confounders [OR for the top quintile = 4.40 (1.65-11.7)]. IGFBP-1 levels were inversely related to endometrial cancer [ptrend = 0.002; OR in the upper quintile = 0.30 (0.15-0.62)], but the association was weakened and lost statistical significance after adjustment for confounders [ptrend = 0.06; OR in the upper quintile = 0.49 (0.22-1.07)]. Risk was unrelated to levels of IGF-I, IGFBP-2 and IGFBP-3. Chronic hyperinsulinemia, as reflected by increased circulating C-peptide, is associated with increased endometrial cancer risk. Decrease in the prevalence of chronic hyperinsulinemia, through changes in lifestyle or medication, is expected to prevent endometrial cancer.

Body-mass index and risk of 22 specific cancers: a population-based cohort study of 5·24 million UK adults
BACKGROUND High body-mass index (BMI) predisposes to several site-specific cancers, but a large-scale systematic and detailed characterisation of patterns of risk across all common cancers adjusted for potential confounders has not previously been undertaken. We aimed to investigate the links between BMI and the most common site-specific cancers. METHODS With primary care data from individuals in the Clinical Practice Research Datalink with BMI data, we fitted Cox models to investigate associations between BMI and 22 of the most common cancers, adjusting for potential confounders. We fitted linear then non-linear (spline) models; investigated effect modification by sex, menopausal status, smoking, and age; and calculated population effects. FINDINGS 5·24 million individuals were included; 166,955 developed cancers of interest. BMI was associated with 17 of 22 cancers, but effects varied substantially by site. Each 5 kg/m(2) increase in BMI was roughly linearly associated with cancers of the uterus (hazard ratio [HR] 1·62, 99% CI 1·56-1·69; p<0·0001), gallbladder (1·31, 1·12-1·52; p<0·0001), kidney (1·25, 1·17-1·33; p<0·0001), cervix (1·10, 1·03-1·17; p=0·00035), thyroid (1·09, 1·00-1·19; p=0·0088), and leukaemia (1·09, 1·05-1·13; p≤0·0001). BMI was positively associated with liver (1·19, 1·12-1·27), colon (1·10, 1·07-1·13), ovarian (1·09, 1.04-1.14), and postmenopausal breast cancers (1·05, 1·03-1·07) overall (all p<0·0001), but these effects varied by underlying BMI or individual-level characteristics. We estimated inverse associations with prostate and premenopausal breast cancer risk, both overall (prostate 0·98, 0·95-1·00; premenopausal breast cancer 0·89, 0·86-0·92) and in never-smokers (prostate 0·96, 0·93-0·99; premenopausal breast cancer 0·89, 0·85-0·94). By contrast, for lung and oral cavity cancer, we observed no association in never smokers (lung 0·99, 0·93-1·05; oral cavity 1·07, 0·91-1·26): inverse associations overall were driven by current smokers and ex-smokers, probably because of residual confounding by smoking amount. Assuming causality, 41% of uterine and 10% or more of gallbladder, kidney, liver, and colon cancers could be attributable to excess weight. We estimated that a 1 kg/m(2) population-wide increase in BMI would result in 3790 additional annual UK patients developing one of the ten cancers positively associated with BMI. INTERPRETATION BMI is associated with cancer risk, with substantial population-level effects. The heterogeneity in the effects suggests that different mechanisms are associated with different cancer sites and different patient subgroups. FUNDING National Institute for Health Research, Wellcome Trust, and Medical Research Council.

Anti-obesity drugs: past, present and future
The ideal anti-obesity drug would produce sustained weight loss with minimal side effects. The mechanisms that regulate energy balance have substantial built-in redundancy, overlap considerably with other physiological functions, and are influenced by social, hedonic and psychological factors that limit the effectiveness of pharmacological interventions. It is therefore unsurprising that anti-obesity drug discovery programmes have been littered with false starts, failures in clinical development, and withdrawals due to adverse effects that were not fully appreciated at the time of launch. Drugs that target pathways in metabolic tissues, such as adipocytes, liver and skeletal muscle, have shown potential in preclinical studies but none has yet reached clinical development. Recent improvements in the understanding of peptidergic signalling of hunger and satiety from the gastrointestinal tract mediated by ghrelin, cholecystokinin (CCK), peptide YY (PYY) and glucagon-like peptide-1 (GLP-1), and of homeostatic mechanisms related to leptin and its upstream pathways in the hypothalamus, have opened up new possibilities. Although some have now reached clinical development, it is uncertain whether they will meet the strict regulatory hurdles required for licensing of an anti-obesity drug. However, GLP-1 receptor agonists have already succeeded in diabetes treatment and, owing to their attractive body-weight-lowering effects in humans, will perhaps also pave the way for other anti-obesity agents. To succeed in developing drugs that control body weight to the extent seen following surgical intervention, it seems obvious that a new paradigm is needed. In other therapeutic arenas, such as diabetes and hypertension, lower doses of multiple agents targeting different pathways often yield better results than strategies that modify one pathway alone. Some combination approaches using peptides and small molecules have now reached clinical trials, although recent regulatory experience suggests that large challenges lie ahead. In future, this polytherapeutic strategy could possibly rival surgery in terms of efficacy, safety and sustainability of weight loss.

Sublime Microglia: Expanding Roles for the Guardians of the CNS
Recent findings challenge the concept that microglia solely function in disease states in the central nervous system (CNS). Rather than simply reacting to CNS injury, infection, or pathology, emerging lines of evidence indicate that microglia sculpt the structure of the CNS, refine neuronal circuitry and network connectivity, and contribute to plasticity. These physiological functions of microglia in the normal CNS begin during development and persist into maturity. Here, we develop a conceptual framework for functions of microglia beyond neuroinflammation and discuss the rich repertoire of signaling and communication motifs in microglia that are critical both in pathology and for the normal physiology of the CNS.

Plasmid-encoded proinsulin preserves C-peptide while specifically reducing proinsulin-specific CD8⁺ T cells in type 1 diabetes.
In type 1 diabetes (T1D), there is an intense inflammatory response that destroys the β cells in the pancreatic islets of Langerhans, the site where insulin is produced and released. A therapy for T1D that targets the specific autoimmune response in this disease while leaving the remainder of the immune system intact, has long been sought. Proinsulin is a major target of the adaptive immune response in T1D. We hypothesized that an engineered DNA plasmid encoding proinsulin (BHT-3021) would preserve β cell function in T1D patients through reduction of insulin-specific CD8⁺ T cells. We studied 80 subjects over 18 years of age who were diagnosed with T1D within the past 5 years. Subjects were randomized 2:1 to receive intramuscular injections of BHT-3021 or BHT-placebo, weekly for 12 weeks, and then monitored for safety and immune responses in a blinded fashion. Four dose levels of BHT-3021 were evaluated: 0.3, 1.0, 3.0, and 6.0 mg. C-peptide was used both as an exploratory efficacy measure and as a safety measure. Islet-specific CD8⁺ T cell frequencies were assessed with multimers of monomeric human leukocyte antigen class I molecules loaded with peptides from pancreatic and unrelated antigens. No serious adverse events related to BHT-3021 were observed. C-peptide levels improved relative to placebo at all doses, at 1 mg at the 15-week time point (+19.5% BHT-3021 versus -8.8% BHT-placebo, P < 0.026). Proinsulin-reactive CD8⁺ T cells, but not T cells against unrelated islet or foreign molecules, declined in the BHT-3021 arm (P < 0.006). No significant changes were noted in interferon-γ, interleukin-4 (IL-4), or IL-10 production in CD4 T cells. Thus, we demonstrate that a plasmid encoding proinsulin reduces the frequency of CD8⁺ T cells reactive to proinsulin while preserving C-peptide over the course of dosing.

In vitro differentiation of transplantable neural precursors from human embryonic stem cells
The remarkable developmental potential and replicative capacity of human embryonic stem (ES) cells promise an almost unlimited supply of specific cell types for transplantation therapies. Here we describe the in vitro differentiation, enrichment, and transplantation of neural precursor cells from human ES cells. Upon aggregation to embryoid bodies, differentiating ES cells formed large numbers of neural tube–like structures in the presence of fibroblast growth factor 2 (FGF-2). Neural precursors within these formations were isolated by selective enzymatic digestion and further purified on the basis of differential adhesion. Following withdrawal of FGF-2, they differentiated into neurons, astrocytes, and oligodendrocytes. After transplantation into the neonatal mouse brain, human ES cell–derived neural precursors were incorporated into a variety of brain regions, where they differentiated into both neurons and astrocytes. No teratoma formation was observed in the transplant recipients. These results depict human ES cells as a source of transplantable neural precursors for possible nervous system repair.

Melatonin and the circadian regulation of sleep initiation, consolidation, structure, and the sleep EEG.
The endogenous circadian rhythm of melatonin, driven by the suprachiasmatic nucleus, exhibits a close association with the endogenous circadian component of the sleep propensity rhythm and the endogenous circadian component of the variation in electroencephalogram (EEG) oscillations such as sleep spindles and slow waves. This association is maintained even when the sleep-wake cycle is desynchronized from the endogenous circadian rhythm of melatonin. Administration of melatonin during the day increases daytime sleep propensity as indexed by both the latency to sleep onset and sleep consolidation. The EEG during daytime sleep after melatonin administration exhibits characteristics reminiscent of the nocturnal sleep EEG, that is, increased sleep spindle activity and reduced slow-wave sleep and slow-wave activity, as detected by quantitative EEG analysis. Administration of higher doses of melatonin (5 mg or more) prior to nocturnal sleep results in an increase in rapid eye movement (REM) sleep. These data demonstrate that melatonin exerts effects on the main characteristics of human sleep, that is, latency to sleep onset, sleep consolidation, slow waves, sleep spindles, and REM sleep. There is a need for further studies using physiological doses and delivery systems that generate physiological plasma melatonin profiles to firmly establish the role of the endogenous circadian rhythm of melatonin in the circadian regulation of sleep.

Early loss of interneurons and delayed subunit-specific changes in GABA(A)-receptor expression in a mouse model of mesial temporal lobe epilepsy.
Unilateral injection of kainic acid (KA) into the dorsal hippocampus of adult mice induces spontaneous recurrent partial seizures and replicates histopathological changes observed in human mesial temporal lobe epilepsy (MTLE) (Bouilleret V et al., Neuroscience 1999; 89:717-729). Alterations in pre- and postsynaptic components of GABAergic neurotransmission were investigated immunohistochemically at different time points (1-120 days) in this mouse model of MTLE. Markers of GABAergic interneurons (parvalbumin, calbindin-D28k, and calretinin), the type-1 GABA transporter (GAT1), and major GABA(A)-receptor subunits expressed in the hippocampal formation were analyzed. Acutely, KA injection produced a profound loss of hilar cells but only limited damage to CA1 and CA3 pyramidal cells. In addition, parvalbumin and calbindin-D28k staining of interneurons disappeared irreversibly in CA1 and dentate gyrus (DG), whereas calretinin staining was spared. The prominent GABA(A)-receptor alpha1 subunit staining of interneurons also disappeared after KA treatment, suggesting acute degeneration of these cells. Likewise, GAT1 immunoreactivity revealed degenerating terminals at 24 h post-KA in CA1 and DC and subsided almost completely thereafter. Loss of CA1 and, to a lesser extent, CA3 neurons became evident at 7-15 days post-KA. It was more accentuated after 1 month, accompanied by a corresponding reduction of GABA(A)-receptor staining. In contrast, DC granule cells were markedly enlarged and dispersed in the molecular layer and exhibited a prominent increase in GABA(A)-receptor subunit staining. After 4 months, the dorsal CA1 area was lost almost entirely, CA3 was reduced, and the DG represented most of the remaining dorsal hippocampal formation. No significant morphological alterations were detected contralaterally. These results suggest that loss of hilar cells and GABAergic neurons contributes to epileptogenesis in this model of MTLE. In contrast, long-term degeneration of pyramidal cells and granule cell dispersion may reflect distinct responses to recurrent seizures. Finally, GABA(A)-receptor upregulation in the DG may represent a compensatory response persisting for several months in epileptic mice.

Detection of alternative lengthening of telomeres by telomere quantitative PCR
Alternative lengthening of telomeres (ALT) is one of the two known telomere length maintenance mechanisms that are essential for the unlimited proliferation potential of cancer cells. Existing methods for detecting ALT in tumors require substantial amounts of tumor material and are labor intensive, making it difficult to study prevalence and prognostic significance of ALT in large tumor cohorts. Here, we present a novel strategy utilizing telomere quantitative PCR to diagnose ALT. The protocol is more rapid than conventional methods and scrutinizes two distinct characteristics of ALT cells concurrently: long telomeres and the presence of C-circles (partially double-stranded circles of telomeric C-strand DNA). Requiring only 30 ng of genomic DNA, this protocol will facilitate large-scale studies of ALT in tumors and can be readily adopted by clinical laboratories.

Variant Histone H2A.Z Is Globally Localized to the Promoters of Inactive Yeast Genes and Regulates Nucleosome Positioning
H2A.Z is an evolutionary conserved histone variant involved in transcriptional regulation, antisilencing, silencing, and genome stability. The mechanism(s) by which H2A.Z regulates these various biological functions remains poorly defined, in part due to the lack of knowledge regarding its physical location along chromosomes and the bearing it has in regulating chromatin structure. Here we mapped H2A.Z across the yeast genome at an approximately 300-bp resolution, using chromatin immunoprecipitation combined with tiling microarrays. We have identified 4,862 small regions—typically one or two nucleosomes wide—decorated with H2A.Z. Those “Z loci” are predominantly found within specific nucleosomes in the promoter of inactive genes all across the genome. Furthermore, we have shown that H2A.Z can regulate nucleosome positioning at the GAL1 promoter. Within HZAD domains, the regions where H2A.Z shows an antisilencing function, H2A.Z is localized in a wider pattern, suggesting that the variant histone regulates a silencing and transcriptional activation via different mechanisms. Our data suggest that the incorporation of H2A.Z into specific promoter-bound nucleosomes configures chromatin structure to poise genes for transcriptional activation. The relevance of these findings to higher eukaryotes is discussed.

Instruction: Given a scientific claim, retrieve documents that support or refute the claim


Question: Tirasemtiv targets fast-twitch muscle.

Activation of fast skeletal muscle troponin as a potential therapeutic approach for treating neuromuscular diseases
Limited neural input results in muscle weakness in neuromuscular disease because of a reduction in the density of muscle innervation, the rate of neuromuscular junction activation or the efficiency of synaptic transmission. We developed a small-molecule fast-skeletal-troponin activator, CK-2017357, as a means to increase muscle strength by amplifying the response of muscle when neural input is otherwise diminished secondary to neuromuscular disease. Binding selectively to the fast-skeletal-troponin complex, CK-2017357 slows the rate of calcium release from troponin C and sensitizes muscle to calcium. As a consequence, the force-calcium relationship of muscle fibers shifts leftwards, as does the force-frequency relationship of a nerve-muscle pair, so that CK-2017357 increases the production of muscle force in situ at sub-maximal nerve stimulation rates. Notably, we show that sensitization of the fast-skeletal-troponin complex to calcium improves muscle force and grip strength immediately after administration of single doses of CK-2017357 in a model of the neuromuscular disease myasthenia gravis. Troponin activation may provide a new therapeutic approach to improve physical activity in diseases where neuromuscular function is compromised.

Novel Functional Sets of Lipid-Derived Mediators with Antiinflammatory Actions Generated from Omega-3 Fatty Acids via Cyclooxygenase 2–Nonsteroidal Antiinflammatory Drugs and Transcellular Processing
Aspirin therapy inhibits prostaglandin biosynthesis without directly acting on lipoxygenases, yet via acetylation of cyclooxygenase 2 (COX-2) it leads to bioactive lipoxins (LXs) epimeric at carbon 15 (15-epi-LX, also termed aspirin-triggered LX [ATL]). Here, we report that inflammatory exudates from mice treated with ω-3 polyunsaturated fatty acid and aspirin (ASA) generate a novel array of bioactive lipid signals. Human endothelial cells with upregulated COX-2 treated with ASA converted C20:5 ω-3 to 18R-hydroxyeicosapentaenoic acid (HEPE) and 15R-HEPE. Each was used by polymorphonuclear leukocytes to generate separate classes of novel trihydroxy-containing mediators, including 5-series 15R-LX5 and 5,12,18R-triHEPE. These new compounds proved to be potent inhibitors of human polymorphonuclear leukocyte transendothelial migration and infiltration in vivo (ATL analogue > 5,12,18R-triHEPE > 18R-HEPE). Acetaminophen and indomethacin also permitted 18R-HEPE and 15R-HEPE generation with recombinant COX-2 as well as ω-5 and ω-9 oxygenations of other fatty acids that act on hematologic cells. These findings establish new transcellular routes for producing arrays of bioactive lipid mediators via COX-2–nonsteroidal antiinflammatory drug–dependent oxygenations and cell–cell interactions that impact microinflammation. The generation of these and related compounds provides a novel mechanism(s) for the therapeutic benefits of ω-3 dietary supplementation, which may be important in inflammation, neoplasia, and vascular diseases.

Inhibition of Hedgehog signaling enhances delivery of chemotherapy in a mouse model of pancreatic cancer.
Pancreatic ductal adenocarcinoma (PDA) is among the most lethal human cancers in part because it is insensitive to many chemotherapeutic drugs. Studying a mouse model of PDA that is refractory to the clinically used drug gemcitabine, we found that the tumors in this model were poorly perfused and poorly vascularized, properties that are shared with human PDA. We tested whether the delivery and efficacy of gemcitabine in the mice could be improved by coadministration of IPI-926, a drug that depletes tumor-associated stromal tissue by inhibition of the Hedgehog cellular signaling pathway. The combination therapy produced a transient increase in intratumoral vascular density and intratumoral concentration of gemcitabine, leading to transient stabilization of disease. Thus, inefficient drug delivery may be an important contributor to chemoresistance in pancreatic cancer.

Direct Reprogramming of Hepatic Myofibroblasts into Hepatocytes In Vivo Attenuates Liver Fibrosis.
Direct induction of induced hepatocytes (iHeps) from fibroblasts holds potential as a strategy for regenerative medicine but until now has only been shown in culture settings. Here, we describe in vivo iHep formation using transcription factor induction and genetic fate tracing in mouse models of chronic liver disease. We show that ectopic expression of the transcription factors FOXA3, GATA4, HNF1A, and HNF4A from a polycistronic lentiviral vector converts mouse myofibroblasts into cells with a hepatocyte phenotype. In vivo expression of the same set of transcription factors from a p75 neurotrophin receptor peptide (p75NTRp)-tagged adenovirus enabled the generation of hepatocyte-like cells from myofibroblasts in fibrotic mouse livers and reduced liver fibrosis. We have therefore been able to convert pro-fibrogenic myofibroblasts in the liver into hepatocyte-like cells with positive functional benefits. This direct in vivo reprogramming approach may open new avenues for the treatment of chronic liver disease.

Dual and opposing roles of primary cilia in medulloblastoma development
Recent work has shown that primary cilia are essential for Hedgehog (Hh) signaling during mammalian development. It is also known that aberrant Hh signaling can lead to cancer, but the role of primary cilia in oncogenesis is not known. Cerebellar granule neuron precursors (GNPs) can give rise to medulloblastomas, the most common malignant brain tumor in children. The primary cilium and Hh signaling are required for GNP proliferation. We asked whether primary cilia in GNPs have a role in medulloblastoma growth in mice. Genetic ablation of primary cilia blocked medulloblastoma formation when this tumor was driven by a constitutively active Smoothened protein (Smo), an upstream activator of Hh signaling. In contrast, removal of cilia was required for medulloblastoma growth by a constitutively active glioma-associated oncogene family zinc finger-2 (GLI2), a downstream transcription factor. Thus, primary cilia are either required for or inhibit medulloblastoma formation, depending on the initiating oncogenic event. Remarkably, the presence or absence of cilia was associated with specific variants of human medulloblastomas; primary cilia were found in medulloblastomas with activation in HH or WNT signaling but not in most medulloblastomas in other distinct molecular subgroups. Primary cilia could serve as a diagnostic tool and provide new insights into the mechanism of tumorigenesis.

Abnormalities in the myeloid progenitor compartment in Down syndrome fetal liver precede acquisition of GATA1 mutations.
Down syndrome (DS) children have a high frequency of acute megakaryoblastic leukemia (AMKL) in early childhood. At least 2 in utero genetic events are required, although not sufficient, for DS-AMKL: trisomy 21 (T21) and N-terminal-truncating GATA1 mutations. To investigate the role of T21 in DS-AMKL, we compared second trimester hemopoiesis in DS without GATA1 mutations to gestation-matched normal controls. In all DS fetal livers (FLs), but not marrows, megakaryocyte-erythroid progenitor frequency was increased (55.9% +/- 4% vs 17.1% +/- 3%, CD34(+)CD38(+) cells; P < .001) with common myeloid progenitors (19.6% +/- 2% vs 44.0% +/- 7%) and granulocyte-monocyte (GM) progenitors (15.8% +/- 4% vs 34.5% +/- 9%) commensurately reduced. Clonogenicity of DS-FL versus normal FL CD34(+) cells was markedly increased (78% +/- 7% vs 15% +/- 3%) affecting megakaryocyte-erythroid ( approximately 7-fold higher) and GM and colony-forming unit-granulocyte, erythrocyte macrophage, megakaryocyte (CFU-GEMM) progenitors. Replating efficiency of CFU-GEMM was also markedly increased. These data indicate that T21 itself profoundly disturbs FL hemopoiesis and they provide a testable hypothesis to explain the increased susceptibility to GATA1 mutations in DS-AMKL and DS-associated transient myeloproliferative disorder.

The Polymeal: a more natural, safer, and probably tastier (than the Polypill) strategy to reduce cardiovascular disease by more than 75%.
OBJECTIVE Although the Polypill concept (proposed in 2003) is promising in terms of benefits for cardiovascular risk management, the potential costs and adverse effects are its main pitfalls. The objective of this study was to identify a tastier and safer alternative to the Polypill: the Polymeal. METHODS Data on the ingredients of the Polymeal were taken from the literature. The evidence based recipe included wine, fish, dark chocolate, fruits, vegetables, garlic, and almonds. Data from the Framingham heart study and the Framingham offspring study were used to build life tables to model the benefits of the Polymeal in the general population from age 50, assuming multiplicative correlations. RESULTS Combining the ingredients of the Polymeal would reduce cardiovascular disease events by 76%. For men, taking the Polymeal daily represented an increase in total life expectancy of 6.6 years, an increase in life expectancy free from cardiovascular disease of 9.0 years, and a decrease in life expectancy with cardiovascular disease of 2.4 years. The corresponding differences for women were 4.8, 8.1, and 3.3 years. CONCLUSION The Polymeal promises to be an effective, non-pharmacological, safe, cheap, and tasty alternative to reduce cardiovascular morbidity and increase life expectancy in the general population.

Development and evaluation of a self-administered computerized 24-h dietary recall method for adolescents in Europe
Objective:To describe the development of a European computerized 24-h dietary recall method for adolescents, and to investigate the feasibility of self-administration (self report) by comparison with administration by a dietician (interview).Methods:Two hundred and thirty-six adolescents (mean age 14.6 years (s.d.=1.7)) of eight European cities completed the 24-h recall (Young Adolescents Nutrition Assessment on Computer (YANA-C)) twice (once by self-report and once by interview).Results:A small but significant underestimate in energy (61 (s.e.=31) kcal) and fat (4.2 (s.e.=1.7) g) intake was found in the self-reports in comparison with the interviews; no significant differences were found for the intake of carbohydrates, proteins, fibre, calcium, iron and ascorbic acid. Spearman's correlations were highly significant for all nutrients and energy ranging between 0.86 and 0.91. Agreement in categorizing the respondents as consumers and non-consumers for the 29 food groups was high (kappa statistics ⩾0.73). Percentage omissions were on average 3.7%; percentage intrusions: 2.0%. Spearman's correlations between both modes were high for all food groups, for the total sample (⩾0.76) as well as for the consumers only (⩾0.72). Analysing the consumer only, on an average 54% of the consumed amounts were exactly the same; nevertheless, only for one group ‘rice and pasta’ a significant difference in consumption was found. Conclusion:Adaptation, translation and standardization of YANA-C make it possible to assess the dietary intake of adolescents in a broad international context. In general, good agreement between the administration modes was found, the latter offering significant potential for large-scale surveys where the amount of resources to gather data is limited.

Early chromatin unfolding by RUNX1: a molecular explanation for differential requirements during specification versus maintenance of the hematopoietic gene expression program.
At the cellular level, development progresses through successive regulatory states, each characterized by their specific gene expression profile. However, the molecular mechanisms regulating first the priming and then maintenance of gene expression within one developmental pathway are essentially unknown. The hematopoietic system represents a powerful experimental model to address these questions and here we have focused on a regulatory circuit playing a central role in myelopoiesis: the transcription factor PU.1, its target gene colony-stimulating-factor 1 receptor (Csf1r), and key upstream regulators such as RUNX1. We find that during ontogeny, chromatin unfolding precedes the establishment of active histone marks and the formation of stable transcription factor complexes at the Pu.1 locus and we show that chromatin remodeling is mediated by the transient binding of RUNX1 to Pu.1 cis-elements. By contrast, chromatin reorganization of Csf1r requires prior expression of PU.1 together with RUNX1 binding. Once the full hematopoietic program is established, stable transcription factor complexes and active chromatin can be maintained without RUNX1. Our experiments therefore demonstrate how individual transcription factors function in a differentiation stage-specific manner to differentially affect the initiation versus maintenance of a developmental program.

MHC Haplotype Matching for Unrelated Hematopoietic Cell Transplantation
Background  Current criteria for the selection of unrelated donors for hematopoietic cell transplantation (HCT) include matching for the alleles of each human leukocyte antigen (HLA) locus within the major histocompatibility complex (MHC). Graft-versus-host disease (GVHD), however, remains a significant and potentially life-threatening complication even after HLA-identical unrelated HCT. The MHC harbors more than 400 genes, but the total number of transplantation antigens is unknown. Genes that influence transplantation outcome could be identified by using linkage disequilibrium (LD)-mapping approaches, if the extended MHC haplotypes of the unrelated donor and recipient could be defined.

Oxidative damage of DNA confers resistance to cytosolic nuclease TREX1 degradation and potentiates STING-dependent immune sensing.
Immune sensing of DNA is critical for antiviral immunity but can also trigger autoimmune diseases such as lupus erythematosus (LE). Here we have provided evidence for the involvement of a damage-associated DNA modification in the detection of cytosolic DNA. The oxidized base 8-hydroxyguanosine (8-OHG), a marker of oxidative damage in DNA, potentiated cytosolic immune recognition by decreasing its susceptibility to 3' repair exonuclease 1 (TREX1)-mediated degradation. Oxidizative modifications arose physiologically in pathogen DNA during lysosomal reactive oxygen species (ROS) exposure, as well as in neutrophil extracellular trap (NET) DNA during the oxidative burst. 8-OHG was also abundant in UV-exposed skin lesions of LE patients and colocalized with type I interferon (IFN). Injection of oxidized DNA in the skin of lupus-prone mice induced lesions that closely matched respective lesions in patients. Thus, oxidized DNA represents a prototypic damage-associated molecular pattern (DAMP) with important implications for infection, sterile inflammation, and autoimmunity.

Instruction: Given a scientific claim, retrieve documents that support or refute the claim