374 research outputs found
Translational control plays a prominent role in the hepatocytic differentiation of HepaRG liver progenitor cells
BACKGROUND: We investigated the molecular events associated with the differentiation of liver progenitor cells into functional and polarized hepatocytes, using human HepaRG cells that display potent hepatocytic differentiation-inducible properties and share some features with liver progenitor cells. RESULTS: Profiling of total and of polysome-bound transcripts isolated from HepaRG cells undergoing hepatocytic differentiation was performed. A group of 3,071 probe sets was reproducibly regulated by at least 2-fold in total or in polysome-bound RNA populations, upon differentiation. The fold changes in the total and the polysome-bound RNA populations for these 3,071 probe sets were poorly correlated (R = 0.38). Moreover, while the majority of the regulated polysome-bound RNA probe sets were up-regulated upon differentiation, the majority of the regulated probe sets selected from the total RNA population was down-regulated. Genes translationally up-regulated were associated with cell cycle inhibition, increased susceptibility to apoptosis and innate immunity. In contrast, genes transcriptionally up-regulated during differentiation corresponded in the majority to liver-enriched transcripts involved in lipid homeostasis and drug metabolism. Finally, several epithelial and hepato-specific transcripts were strongly induced in the total RNA population but were translationally repressed. CONCLUSION: Translational regulation is the main genomic event associated with hepatocytic differentiation of liver progenitor cells in vitro and targets genes critical for moderating hepatocellular growth, cell death and susceptibility to pathogens. Transcriptional regulation targets specifically liver-enriched transcripts vital for establishing normal hepatic energy homeostasis, cell morphology and polarization. The hepatocytic differentiation is also accompanied by a reduction of the transcript content complexity
The 2006 Human Liver Proteome Project (HLPP) Workshops
In 2006, scientists participating to the Human Liver Proteome Project (HLPP) launched
by the Human Proteome Organisation (HUPO) convened on two occasions to present and
discuss their progress. A workshop was held over two days in May in Bilbao, Spain, and a brief
3-hour meeting was held in October in conjunction with the 5th HUPO World Congress in Long
Beach, California. Highlights included progress on the construction of the human normal liver
proteome expression profile and of subcellular proteomes, establishment of a liver ORFeome
bank and of a liver antibody bank, identifications of protein-protein interaction maps in the liver,
application of a robust strategy for quantitative proteomics and the characterization of fatty liver
diseases using mouse models
Biochemical and morphological changes in endothelial cells in response to hypoxic interstitial edema
BACKGROUND: A correlation between interstial pulmonary matrix disorganization and lung cellular response was recently documented in cardiogenic interstitial edema as changes in the signal-cellular transduction platforms (lipid microdomains: caveoale and lipid rafts). These findings led to hypothesize a specific "sensing" function by lung cells resulting from a perturbation in cell-matrix interaction. We reason that the cell-matrix interaction may differ between the cardiogenic and the hypoxic type of lung edema due to the observed difference in the sequential degradation of matrix proteoglycans (PGs) family. In cardiogenic edema a major fragmentation of high molecular weight PGs of the interfibrillar matrix was found, while in hypoxia the fragmentation process mostly involved the PGs of the basement membrane controlling microvascular permeability. Based on these considerations, we aim to describe potential differences in the lung cellular response to the two types of edema. METHODS: We analysed the composition of plasma membrane and of lipid microdomains in lung tissue samples from anesthetized rabbits exposed to mild hypoxia (12 % O(2 )for 3–5 h) causing interstitial lung edema. Lipid analysis was performed by chromatographic techniques, while protein analysis by electrophoresis and Western blotting. Lipid peroxidation was assessed on total plasma membranes by a colorimetric assay (Bioxytech LPO-586, OxisResearch). Plasma membrane fluidity was also assessed by fluorescence. Lipid microdomains were isolated by discontinuous sucrose gradient. We also performed a morphometric analysis on lung cell shape on TEM images from lung tissue specimen. RESULTS: After hypoxia, phospholipids content in plasma membranes remained unchanged while the cholesterol/phospholipids ratio increased significantly by about 9% causing a decrease in membrane fluidity. No significant increase in lipid peroxidation was detected. Analysis of lipid microdomains showed a decrease of caveolin-1 and AQP1 (markers of caveolae), and an increase in CD55 (marker of lipid rafts). Morphometry showed a significant decrease in endothelial cell volume, a marked increase in the cell surface/volume ratio and a decrease in caveolar density; epithelial cells did not show morphological changes. CONCLUSION: The biochemical, signaling and morphological changes observed in lung endothelial cell exposed to hypoxia are opposite to those previously described in cardiogenic edema, suggesting a differential cellular response to either type of edema
Biosecurity during nursing care to patients with pulmonary tuberculosis
OBJECTIVE: To evaluate preventive measures recommended during patient care for respiratory symptoms, with pulmonary tuberculosis. METHODS: Exploratory-descriptive study, retrospective, developed from information collected in medical records of patients with respiratory symptoms, diagnosed with pulmonary tuberculosis. RESULTS: The number of tuberculosis cases in the city diagnosed during hospitalization during the study period was 65,29 (44.6%). As for the biosecurity measures during the hospitalization of 29 diagnosed cases, early aerosol were found in medical records in 13 (44.8%) patients. CONCLUSION: Data show that nursing professionals, working in hospitals, still exposed to risks of latent infection.OBJETIVO: Avaliar as medidas preventivas recomendadas durante a assistência aos pacientes sintomáticos respiratórios, com tuberculose pulmonar. MÉTODOS: Estudo exploratório-descritivo, retrospectivo, desenvolvido a partir deinformações coletadasnos arquivosde pacientes sintomáticos respiratórios, com diagnóstico de saÃda tuberculose pulmonar. RESULTADOS: O número de casos de tuberculose no municÃpio durante o perÃodo do estudo foi de 65, 29 (44,6%) destes casos foram diagnosticados durante a internação. Quanto as medidas de biossegurança, durante a admissão dos 29 casos diagnosticados, foram encontrados registros de precaução por aerossóis nos prontuários de 13 (44,8%) pacientes. CONCLUSÃO: Os dados mostram que os profissionaisde enfermagem, que trabalham nos hospitais, continuam expostos aorisco de infecção latente.Fundação HermÃnio OmettoUniversidade Federal de São Paulo (UNIFESP)UNIFESPSciEL
Hepatitis C Virus in Mexican Americans: a population-based study reveals relatively high prevalence and negative association with diabetes
This study aimed to estimate the prevalence and risk factors for hepatitis C virus (HCV) infection in Mexican Americans living in South Texas. We tested plasma for the presence of HCV antibody from the Cameron County Hispanic Cohort (CCHC), a randomized, population-based cohort in an economically disadvantaged Mexican American community on the United States/Mexico border with high rates of chronic disease. A weighted prevalence of HCV antibody of 2·3% [n = 1131, 95% confidence interval (CI) 1·2-3·4] was found. Participants with diabetes had low rates of HCV antibody (0·4%, 95% CI 0·0-0·9) and logistic regression revealed a statistically significant negative association between HCV and diabetes (OR 0·20, 95% CI 0·05-0·77) after adjusting for sociodemographic and clinical factors. This conflicts with reported positive associations of diabetes and HCV infection. No classic risk factors were identified, but important differences between genders emerged in analysis. This population-based study of HCV in Mexican Americans suggests that national studies do not adequately describe the epidemiology of HCV in this border community and that unique risk factors may be involved
Extracellular Matrix Dynamics in Hepatocarcinogenesis: a Comparative Proteomics Study of PDGFC Transgenic and Pten Null Mouse Models
We are reporting qualitative and quantitative changes of the extracellular matrix (ECM) and associated receptor proteomes, occurring during the transition from liver fibrosis and steatohepatitis to hepatocellular carcinoma (HCC). We compared two mouse models relevant to human HCC: PDGFC transgenic (Tg) and Pten null mice, models of disease progression from fibrosis and steatohepatitis to HCC. Using mass spectrometry, we identified in the liver of both models proteins for 26 collagen-encoding genes, providing the first evidence of expression at the protein level for 16 collagens. We also identified post-transcriptional protein variants for six collagens and lysine hydroxylation modifications for 14 collagens. Tumor-associated collagen proteomes were similar in both models with increased expression of collagens type IV, VI, VII, X, XIV, XV, XVI, and XVIII. Splice variants for Col4a2, Col6a2, Col6a3 were co-upregulated while only the short form of Col18a1 increased in the tumors. We also identified tumor specific increases of nidogen 1, decorin, perlecan, and of six laminin subunits. The changes in these non-collagenous ECM proteins were similar in both models with the exception of laminin β3, detected specifically in the Pten null tumors. Pdgfa and Pdgfc mRNA expression was increased in the Pten null liver, a possible mechanism for the similarity in ECM composition observed in the tumors of both models. In contrast and besides the strong up-regulation of integrin α5 protein observed in the liver tumors of both models, the expression of the six other integrins identified was specific to each model, with integrins α2b, α3, α6, and β1 up-regulated in Pten null tumors and integrins α8 and β5 up-regulated in the PDGFC Tg tumors. In conclusion, HCC–associated ECM proteins and ECM–integrin networks, common or specific to HCC subtypes, were identified, providing a unique foundation to using ECM composition for HCC classification, diagnosis, prevention, or treatment
The Precarious Health of Young Mexican American Men in South Texas, Cameron County Hispanic Cohort, 2004–2015
Introduction
Hispanic men have higher rates of illness and death from various chronic conditions than do non-Hispanic men. We aimed to characterize the health of Mexican American men living on the US–Mexico border in South Texas and elucidate indications of chronic disease in young men.
Methods
We sampled all male participants from the Cameron County Hispanic Cohort, an ongoing population-based cohort of Mexican Americans in Brownsville, Texas. We calculated descriptive statistics and stratified the sample into 3 age groups to estimate the prevalence of sociodemographic, behavioral, and clinical factors by age group and evaluated differences between age groups.
Results
Obesity prevalence was approximately 50% across all age groups (P = .83). Diabetes prevalence was high overall (26.8%), and 16.9% (95% confidence interval [CI], 10.1%–23.8%) of men younger than 35 had diabetes. More than 70% of these young men had elevated liver enzymes, and mean values of aspartate aminotransferase were significantly higher in younger men (45.0 u/L; 95% CI, 39.5–50.6 u/L) than in both older age groups. Less than 20% of young men had any form of health insurance. Current smoking was higher in young men than in men in the other groups, and the rate was higher than the national prevalence of current smoking among Hispanic men.
Conclusions
We suggest a need for obesity and diabetes prevention programs and smoking cessation programs for men in this region. Opportunities exist to expand current intervention programs and tailor them to better reach this vulnerable population of young Hispanic men. Elevated liver enzymes in men younger than 35 suggest a substantial burden of liver abnormalities, a finding that warrants further study
Interstitial Lung Disease Associated With Autoimmune Rheumatic Diseases: Checklists for Clinical Practice
Background: Interstitial lung diseases (ILDs) are often associated with rheumatic diseases. Their early diagnosis and management are not only difficult, but also crucial, because they are associated with major morbidity and mortality and can be the first cause of death in autoimmune rheumatic diseases (ARDs). Objectives: By using methodologies, such as Nominal Group Technique (NGT) and Delphi Survey, the aims of this study were (1) to measure consensus between pulmonologists, radiologists, and rheumatologists experienced in the management of ARD-ILD; (2) to highlight the importance of a multidisciplinary approach; and (3) to provide clinicians with a practical tool aimed at improving the prompt recognition and follow-up of ILD associated with ARDs and of any possible rheumatic conditions underlying ILD. Results: During the NGT round, the Steering Committee defined 57 statements to be used in the Delphi survey. A total of 78 experts participated in the Delphi survey, namely 28 pulmonologists, 33 rheumatologists, and 17 radiologists. During this round, consensus on agreement was reached in 47 statements, while disagreement was not reached in any statements. A secondary questionnaire was drafted by the Steering Committee to obtain clearer indications on ILD-ARD \u201cred-flags\u201d and follow-up. Delphi Panelists took part also in the second-questionnaire survey. Answers from both surveys were used to draft two checklists of \u201cred flags\u201d sign or symptom suggestive of ILD and ARD, respectively, and two checklists on identification and monitoring of rheumatoid arthritis (RA) and systemic sclerosis (SSc) ILD. Limitations: This study is a consensus work, which cannot produce empiric data, and is limited to the Italian scenario. Conclusions: This work showed a high level of agreement, but also shows some divergent opinions between different experts. This underlines the importance of a multidisciplinary approach. Eventually, we believe the drafted checklists can help clinicians in the diagnosis and follow-up of ILD-ARD
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