142 research outputs found
Graph attention automatic encoder based on contrastive learning for domain recognition of spatial transcriptomics
Spatial transcriptomics is an emerging technology that enables the profiling of gene expression in tissues while preserving spatial location information. This innovative approach is anticipated to provide a comprehensive understanding of the spatial distribution of different cells within tissues and facilitate in-depth analysis of tissue structure. To accurately recognize spatial domains from spatial transcriptomics, we have introduced a generalized deep learning method called GAAEST (Graph Attention-based Autoencoder for Spatial Transcriptomics). Our proposed approach effectively integrates both spatial location information and gene expression data from spatial transcriptomics. Specifically, it leverages spatial location details to construct a neighborhood graph and employs a graph attention network-based encoder to embed gene expression information into a spatially informed space. At the same time, to further optimize the learned potential embedding, self-supervised contrastive learning is introduced to capture spatial information at three levels: local, global and contextual feature of spots. Finally, the decoder reconstructs gene expressions, which are then clustered to identify spatial domains with similar expression patterns and spatial proximity. Based on our experiments conducted on multiple datasets, GAAEST consistently outperforms existing state-of-the-art methods. The proposed GAAEST demonstrates excellent capabilities in spatial domain recognition, positioning it as an ideal tool for advancing spatial transcriptomics research
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Glucose inhibits cardiac muscle maturation through nucleotide biosynthesis.
The heart switches its energy substrate from glucose to fatty acids at birth, and maternal hyperglycemia is associated with congenital heart disease. However, little is known about how blood glucose impacts heart formation. Using a chemically defined human pluripotent stem-cell-derived cardiomyocyte differentiation system, we found that high glucose inhibits the maturation of cardiomyocytes at genetic, structural, metabolic, electrophysiological, and biomechanical levels by promoting nucleotide biosynthesis through the pentose phosphate pathway. Blood glucose level in embryos is stable in utero during normal pregnancy, but glucose uptake by fetal cardiac tissue is drastically reduced in late gestational stages. In a murine model of diabetic pregnancy, fetal hearts showed cardiomyopathy with increased mitotic activity and decreased maturity. These data suggest that high glucose suppresses cardiac maturation, providing a possible mechanistic basis for congenital heart disease in diabetic pregnancy
Association between genetic variants and development of antibodies to infliximab: A cross-sectional study in Chinese patients with Crohn’s disease
Aims: Genetic variants increase the susceptibility to anti-drug antibodies (ADA) in response to anti-TNF therapy in chronic inflammatory diseases. However, little is known about genetic variants in Chinese populations. This study aimed to identify genetic variants contributing to the risk of the development of antibodies to infliximab (ATI) in Chinese patients with Crohn’s disease (CD).Methods: CD patients (n = 104) treated with infliximab (IFX) during the maintenance therapy were enrolled in this cross-sectional study. ATI was assessed by an in-house developed drug-tolerant ELISA method. ATI titers of 1:20 and ≥1:60 were considered a low titer and a high titer, respectively. Thirteen types of single nucleotide polymorphisms (SNPs) within 13 genes involved in the immune process, the susceptibility to chronic inflammatory diseases, cytokines and apoptosis pathways were investigated.Results: The median trough levels of infliximab (TLI) in patients with clinical remission (CR) were higher than those in patients without CR (3.80 vs. 1.50 μg/mL, p < .001). The median TLI in patients with high-titer ATI was significantly lower than that in ATI-negative patients (1.15 vs. 4.48 μg/mL, p < .001) or those with low-titer ATI (1.15 vs. 2.95 μg/mL, p = .03). The HLA-DQA1*05 rs2097432 GG and GA genotypes were more frequent in patients with ATI (GG and AG vs. AA, 27/38 = 71.05% vs. 29/66 = 43.94%, OR 2.94, 95% CI 1.19–7.30, p = .02). Patients carrying the CC and AC genotypes of rs396991 in FCGR3A were associated with a higher frequency of ATI formation (CC and AC vs. AA, 37/57 = 64.91% vs. 19/47 = 40.43%, OR 2.94, 95% CI 1.24–6.96, p = .01). According to the number of variants in rs2097432 and rs393991, patients with two variants had a higher proportion of producing ATI (two variants vs. no variant, 17/21 = 80.95% vs. 9/30 = 30.00%, OR 9.92, 95% CI 2.59–37.87, p = .001; single variant vs. no variant, 30/53 = 56.60% vs. 9/30 = 30.00%, OR 3.04, 95% CI 1.18–7.88, p = .02). No association was found between other SNPs and ATI production.Conclusion: Rs2097432 in HLA-DQA1*05 and rs396991 in FCGR3A are associated with ATI production in Chinese patients with CD. A pharmacogenomic strategy could help with the clinical management of CD
Suckling Piglet Intestinal Enterocyte Nutrient Metabolism Changes
Background/Aims: Intestinal morphology and the types of enterocytes are changed in piglets during the suckling period, but it is unclear whether these changes are associated with metabolic changes in epithelium. The present study was conducted to test the hypothesis that glucose, fatty acids, and amino acid metabolism in differentiated piglet enterocytes changed during suckling. Methods: Twenty-four piglets (Duroc × [Landrace × Yorkshire]) from 8 litters (3 piglets/litter) were selected. A single piglet from each litter was randomly selected and euthanized at days 7, 14, and 21. Differentiated enterocytes (DE) were isolated from their mid-jejunum. Isobaric tags for relative and absolute quantification and subsequent liquid chromatography-tandem mass spectrometry were used to identify and measure protein synthesis. Results: The results showed that various activities, including: cellular processes; metabolic processes; biological regulation; pigmentation; and, localization, in DEs changed during suckling. Metabolic process analyses revealed that protein expression related to glycolysis and citrate cycle was decreased from day 7 to day 14. The number of differentiated enterocytes of 21 d piglets increased compared to 7 d piglets. Most of the proteins involved in fatty acid and amino acids metabolism had decreased DE expression between day 7 and day 14. Some, but not all, detected proteins down-regulated in DEs of 21 day piglets compared to 7 day piglets. Conclusion: These results indicate that glucose, fatty acids, and amino acids metabolism changed during suckling. This may provide useful information for designing feed formulas and regulating piglet intestinal growth and development
Effect of Smoking on Lung Function Decline in a Retrospective Study of a Health Examination Population in Chinese Males
Objective:China has established a goal of reducing adult smoking prevalence from 27.7% to 20% by 2030. Understanding the possible ongoing impairment in lung function in smokers, is critically important to encourage the populations to change their smoking behavior.MethodsA total of 14,273 males joined the health examination at Huadong Sanatorium from Jan 2012 to Dec 2019 were included. In cross-sectional analysis, we used multiple linear regression to evaluate the association between baseline lung function and smoking status. Then, 3,558 males who received ≥2 spirometry exams were analyzed in longitudinal study. Annual lung function decline was compared using mixed linear models adjusted for confounders.ResultsIn cross-sectional analysis, compared with never-smokers, decreases of −133.56 mL (95% CI: −167.27, −99.85) and −51.44 mL (−69.62, −33.26) in FEV1, −1.48% (−1.94, −1.02) and −1.29% (−1.53, −1.04) in FEV1/FVC were observed in former and current smokers. In longitudinal analysis, significant declines were observed in FEV1 [5.04 (2.30, 7.78) mL] and FEV1/FVC [0.09 (0.05, 0.13) %] in current smokers but not observed in former smokers after adjustment. Participants with long duration of smoking cessation had decelerate lung function than short duration. The annual decline rate of current smokers with high smoking intensity (≥30 cigarettes per day) was 13.80 and 14.17 times greater than that of never-smokers in FEV1 and FVC. Thus, early smoking cessation can slow down lung function decline trend for current smokers.ConclusionsThe harms of current smoking on lung function emphasize the necessity of smoking cessation, especially for those with comorbidities
A study of HIV/AIDS related knowledge, attitude and behaviors among female sex workers in Shanghai China
<p>Abstract</p> <p>Background</p> <p>China is currently facing a rapid and widespread increase in human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS). The activities of female sex workers (FSWs) have contributed to the mounting epidemic of HIV/AIDS and other sexually transmitted diseases (STDs). Therefore, this study aimed to assess the HIV/AIDS-related knowledge, attitude and risk behaviors among FSWs operating in Shanghai China.</p> <p>Methods</p> <p>A cross-sectional study was conducted in five districts of Shanghai, including three suburbs and two downtown locales. We adopted a cluster randomized sampling method to obtain ten geographic sites which consisted of one or more communities/villages proximal to a location where FSWs were accessible. A total of 324 FSWs from 109 Xitou Fang, massage parlors and hair salons who explicitly provided sexual services were enrolled in the study. Each participant completed a questionnaire survey and interview aimed to collect information on the individual's knowledge, attitude, and behaviors associated with risk for HIV/AIDs.</p> <p>Results</p> <p>The overall correct answer rate of HIV/AIDS-related knowledge was 60.8%, and the knowledge of FSWs from downtown areas was significantly higher than those from suburban areas (<it>P </it>< 0.05). The percentage of FSWs who reported having experiences in commercial sexual services without the use of condoms was 33.6%. Condom slippage or breakage was reported as having occurred at least once by 51.2% of the FSWs. FSWs from suburban areas were found to more often engage in high-risk behaviors, including oral and anal sex, than those from downtown areas (<it>P </it>< 0.001). Many of the FSWs (65.7%) reported having non-client sexual partners (most were identified as boyfriends or husbands); however, condom usage with these partners were lower (34.3%).</p> <p>Conclusions</p> <p>Based on the findings from our survey, we advise that promotion of HIV/AIDS-related knowledge be targeted towards FSWs in Shanghai, especially those operating in the suburbs. HIV prevention efforts, such as urging constant condom usage with both clients and steady partners, should be sustained and reinforced among the female sex workers population.</p
Monoclonal Antibodies against Accumulation-Associated Protein Affect EPS Biosynthesis and Enhance Bacterial Accumulation of Staphylococcus epidermidis
Because there is no effective antibiotic to eradicate Staphylococcus epidermidis biofilm infections that lead to the failure of medical device implantations, the development of anti-biofilm vaccines is necessary. Biofilm formation by S. epidermidis requires accumulation-associated protein (Aap) that contains sequence repeats known as G5 domains, which are responsible for the Zn2+-dependent dimerization of Aap to mediate intercellular adhesion. Antibodies against Aap have been reported to inhibit biofilm accumulation. In the present study, three monoclonal antibodies (MAbs) against the Aap C-terminal single B-repeat construct followed by the 79-aa half repeat (AapBrpt1.5) were generated. MAb18B6 inhibited biofilm formation by S. epidermidis RP62A to 60% of the maximum, while MAb25C11 and MAb20B9 enhanced biofilm accumulation. All three MAbs aggregated the planktonic bacteria to form visible cell clusters. Epitope mapping revealed that the epitope of MAb18B6, which recognizes an identical area within AapBrpt constructs from S. epidermidis RP62A, was not shared by MAb25C11 and MAb20B9. Furthermore, all three MAbs were found to affect both Aap expression and extracellular polymeric substance (EPS, including extracellular DNA and PIA) biosynthesis in S. epidermidis and enhance the cell accumulation. These findings contribute to a better understanding of staphylococcal biofilm formation and will help to develop epitope-peptide vaccines against staphylococcal infections
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