162 research outputs found
Exploiting symmetries in SDP-relaxations for polynomial optimization
In this paper we study various approaches for exploiting symmetries in
polynomial optimization problems within the framework of semi definite
programming relaxations. Our special focus is on constrained problems
especially when the symmetric group is acting on the variables. In particular,
we investigate the concept of block decomposition within the framework of
constrained polynomial optimization problems, show how the degree principle for
the symmetric group can be computationally exploited and also propose some
methods to efficiently compute in the geometric quotient.Comment: (v3) Minor revision. To appear in Math. of Operations Researc
Raw Garlic Consumption and Risk of Liver Cancer: A Population-Based Case-Control Study in Eastern China.
Although the major risk factors for liver cancer have been established, preventive factors for liver cancer have not been fully explored. We evaluated the association between raw garlic consumption and liver cancer in a large population-based case-control study in Eastern China. The study was conducted in Jiangsu, China, from 2003 to 2010. A total of 2011 incident liver cancer cases and 7933 randomly selected population-controls were interviewed. Epidemiological data including raw garlic intake and other exposures were collected, and serum markers of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection were assayed. Overall, eating raw garlic twice or more per week was inversely associated with liver cancer, with an adjusted odds ratio (aOR) of 0.77 (95% confidence interval (CI): 0.62-0.96) compared to those ingesting no raw garlic or less than twice per week. In stratified analyses, high intake of raw garlic was inversely associated with liver cancer among Hepatitis B surface antigen (HBsAg) negative individuals, frequent alcohol drinkers, those having history of eating mold-contaminated food or drinking raw water, and those without family history of liver cancer. Marginal interactions on an additive scale were observed between low raw garlic intake and HBsAg positivity (attributable proportion due to interaction (AP) = 0.31, 95% CI: -0.01-0.62) and heavy alcohol drinking (AP = 0.28, 95% CI: 0.00-0.57). Raw garlic consumption is inversely associated with liver cancer. Such an association shed some light on the potential etiologic role of garlic intake on liver cancer, which in turn might provide a possible dietary intervention to reduce liver cancer in Chinese population
The optimisation of whiteness of polyester fabric treated with nanoparticles of 2,2′-(vinylenedi-p-phenylene)bis-benzoxazole (OB-1) by the Taguchi method
This study explores a new approach to achieve a whitening effect on polyester fabric by utilizing a ground form of raw OB-1 (OB-1-G) in combination with dispersing agents. The whitening process parameters, such as whitening temperature, OB-1-G mass, and whitening time were optimized using the L16 orthogonal array-based Taguchi methodology. The signal-to-noise ratio was carried out through a larger-is-better approach to augment the parameter responses, specifically the whiteness. The results suggest that the degree of whiteness of polyester fabric is significantly affected by the whitening treatment temperature (P < 0.05), with a contribution percentage of 93.87%. A whiteness index of 94.12 was achieved for the polyester fabric treated at the optimized conditions. The fabric treated with OB-1-G at the optimized conditions was characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and X-ray diffraction (XRD). The investigation also included the correlation between the length of time spent in washing and rubbing, and their efficacy in achieving whitening outcomes. The research demonstrated the effectiveness of OB-1-G nanopowder in combination with dispersing agents as a fluorescent optical brightener for the optical brightening of polyester fiber with potential use in the textile industry on a larger scale
Calcium Supplementation Enhanced Adipogenesis and Improved Glucose Homeostasis Through Activation of Camkii and PI3K/Akt Signaling Pathway in Porcine Bone Marrow Mesenchymal Stem Cells (pBMSCs) and Mice Fed High Fat Diet (HFD)
Background/Aims: It has been implicated that calcium supplementation is involved in reducing body weight/fat and improving glucose homeostasis. However, the underlying mechanisms are still not fully understood. Here, we investigated the effects of calcium supplementation on adipogenesis and glucose homeostasis in porcine bone marrow mesenchymal stem cells (pBMSCs) and high fat diet (HFD)-fed mice and explored the involved signaling pathways. Methods: In vitro, pBMSCs were treated with 4 mM extracellular calcium ([Ca2+]o) and/or 1 μM nifedipine, 0.1 μM BAPTA-AM, 1 μM KN-93, 50 nM wortmannin for 10 days. The intracellular calcium ([Ca2+]i) levels were measured using Fluo 3-AM by flow cytometry. The adipogenic differentiation of pBMSCs was determined by Oil Red-O staining and triglyceride assay. The expression of marker genes involved in adipogenesis (peroxisome proliferator activated receptor γ (PPARγ) and CCAAT/enhancer binding protein α (C/EBPα)) and glucose uptake (glucose transporter 4 (GLUT4)), as well as the activation of Ca2+/calmodulin-dependent protein kinase II (CaMKII) and PI3K/Akt-FoxO1/AS160 signaling pathways were determined by Western blotting. Glucose uptake and utilization were examined using 2-NBDG assay and glucose content assay, respectively. In vivo, C57BL/6J male mice were fed a HFD (containing 1.2% calcium) without or with 0.6% (w/w) calcium chloride in drinking water for 13 weeks. The adipogenesis, glucose homeostasis and the involvement of CaMKII and PI3K/Akt signaling pathway were also assessed. Results: In vitro, [Ca2+]o stimulated pBMSCs adipogenesis by increasing [Ca2+]i level and activating CaMKII and PI3K/Akt-FoxO1 pathways. In addition, [Ca2+]o promoted glucose uptake/utilization by enhancing AS160 phosphorylation, GLUT4 expression and translocation. However, the stimulating effects of [Ca2+]o on pBMSCs adipogenesis and glucose uptake/utilization were abolished by L-VGCC blocker Nifedipine, [Ca2+]i chelator BAPTA-AM, CaMKII inhibitor KN-93, or PI3K inhibitor Wortmannin. In vivo, calcium supplementation decreased body weight and fat content, increased adipocyte number, and improved glucose homeostasis, with elevated PPARγ and GLUT4 expression and PI3K/Akt activation in iWAT. Conclusion: calcium supplementation enhanced adipogenesis and glucose uptake in pBMSCs, which was coincident with the increased adipocyte number and improved glucose homeostasis in HFD-fed mice, and was associated with activation of CaMKII and PI3K/Akt-FoxO1/AS160 pathways. These data provided a broader understanding of the mechanisms underlying calcium-induced body weight/fat loss and glycemic control
Impaired health-related quality of life in idiopathic inflammatory myopathies : a cross-sectional analysis from the COVAD-2 e-survey
OBJECTIVES
To investigate health-related quality of life in patients with idiopathic inflammatory myopathies (IIMs) compared with those with non-IIM autoimmune rheumatic diseases (AIRDs), non-rheumatic autoimmune diseases (nrAIDs) and without autoimmune diseases (controls) using Patient-Reported Outcome Measurement Information System (PROMIS) instrument data obtained from the second COVID-19 vaccination in autoimmune disease (COVAD-2) e-survey database.
METHODS
Demographics, diagnosis, comorbidities, disease activity, treatments and PROMIS instrument data were analysed. Primary outcomes were PROMIS Global Physical Health (GPH) and Global Mental Health (GMH) scores. Factors affecting GPH and GMH scores in IIMs were identified using multivariable regression analysis.
RESULTS
We analysed responses from 1582 IIM, 4700 non-IIM AIRD and 545 nrAID patients and 3675 controls gathered through 23 May 2022. The median GPH scores were the lowest in IIM and non-IIM AIRD patients {13 [interquartile range (IQR) 10-15] IIMs vs 13 [11-15] non-IIM AIRDs vs 15 [13-17] nrAIDs vs 17 [15-18] controls, P < 0.001}. The median GMH scores in IIM patients were also significantly lower compared with those without autoimmune diseases [13 (IQR 10-15) IIMs vs 15 (13-17) controls, P < 0.001]. Inclusion body myositis, comorbidities, active disease and glucocorticoid use were the determinants of lower GPH scores, whereas overlap myositis, interstitial lung disease, depression, active disease, lower PROMIS Physical Function 10a and higher PROMIS Fatigue 4a scores were associated with lower GMH scores in IIM patients.
CONCLUSION
Both physical and mental health are significantly impaired in IIM patients, particularly in those with comorbidities and increased fatigue, emphasizing the importance of patient-reported experiences and optimized multidisciplinary care to enhance well-being in people with IIMs
Genome-Wide Analysis of Histone H3 Lysine9 Modifications in Human Mesenchymal Stem Cell Osteogenic Differentiation
Mesenchymal stem cells (MSCs) possess self-renewal and multi-lineage differentiation potentials. It has been established that epigenetic mechanisms such as histone modifications could be critical for determining the fate of stem cells. In this study, full human genome promoter microarrays and expression microarrays were used to explore the roles of histone modifications (H3K9Ac and H3K9Me2) upon the induction of MSC osteogenic differentiation. Our results revealed that the enrichment of H3K9Ac was decreased globally at the gene promoters, whereas the number of promoters enriched with H3K9Me2 was increased evidently upon osteogenic induction. By a combined analysis of data from both ChIP-on-chip and expression microarrays, a number of differentially expressed genes regulated by H3K9Ac and/or H3K9Me2 were identified, implicating their roles in several biological events, such as cell cycle withdraw and cytoskeleton reconstruction that were essential to differentiation process. In addition, our results showed that the vitamin D receptor played a trans-repression role via alternations of H3K9Ac and H3K9Me2 upon MSC osteogenic differentiation. Data from this study suggested that gene activation and silencing controlled by changes of H3K9Ac and H3K9Me2, respectively, were crucial to MSC osteogenic differentiation
Responsiveness of genes to manipulation of transcription factors in ES cells is associated with histone modifications and tissue specificity
<p>Abstract</p> <p>Background</p> <p>In addition to determining static states of gene expression (high vs. low), it is important to characterize their dynamic status. For example, genes with H3K27me3 chromatin marks are not only suppressed but also poised for activation. However, the responsiveness of genes to perturbations has never been studied systematically. To distinguish gene responses to specific factors from responsiveness in general, it is necessary to analyze gene expression profiles of cells responding to a large variety of disturbances, and such databases did not exist before.</p> <p>Results</p> <p>We estimated the responsiveness of all genes in mouse ES cells using our recently published database on expression change after controlled induction of 53 transcription factors (TFs) and other genes. Responsive genes (<it>N </it>= 4746), which were readily upregulated or downregulated depending on the kind of perturbation, mostly have regulatory functions and a propensity to become tissue-specific upon differentiation. Tissue-specific expression was evaluated on the basis of published (GNF) and our new data for 15 organs and tissues. Non-responsive genes (<it>N </it>= 9562), which did not change their expression much following any perturbation, were enriched in housekeeping functions. We found that TF-responsiveness in ES cells is the best predictor known for tissue-specificity in gene expression. Among genes with CpG islands, high responsiveness is associated with H3K27me3 chromatin marks, and low responsiveness is associated with H3K36me3 chromatin, stronger tri-methylation of H3K4, binding of E2F1, and GABP binding motifs in promoters.</p> <p>Conclusions</p> <p>We thus propose the responsiveness of expression to perturbations as a new way to define the dynamic status of genes, which brings new insights into mechanisms of regulation of gene expression and tissue specificity.</p
Community-acquired necrotizing pneumonia due to methicillin-sensitive Staphylococcus aureus secreting Panton-Valentine leukocidin: a review of case reports
Secreted phospholipase A2 of Clonorchis sinensis activates hepatic stellate cells through a pathway involving JNK signalling
Flares in IIMs and the timeline following COVID-19 vaccination: a combined analysis of the COVAD-1 and 2 surveys
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