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Biology subjects

Zhao, K.

Publications and source records attributed to Zhao, K..

5 recordsLinked to original sources

Diagnosis of Osteoarthritis Subtypes with Blood Biomarkers

ObjectiveTo identity osteoarthritis(OA) subtypes with gene expression of peripheral blood mononuclear cells.\n\nMethodsGene expression data (GSE48556) of Genetics osteoARthritis and Progression (GARP) study was downloaded from Gene Expression Omnibus. Principal component analysis and unsupervised clustering were analyzed to identify subtypes of OA and compare major KEGG pathways and cell type enrichment using GSEA and xCell. Classification of subtypes were explored by the utilization of support vector machine.\n\nResultsUnsupervised clustering identified two distinct OA subtypes: Group A comprised of 60 patients (56.6%) and Group B had 46 patients (43.3%). A classifier including nine genes and CD4+ T cell and Regulatory T cell flow cytometry could accurately distinguish patients from each group (area under the curve of 0.99 with gene expression). Group A is typical degenerative OA with glycosaminoglycan biosynthesis and apoptosis. Group B is related to Graft versus host disease and antigen processing and presentation, which indicated OA has a new type of \"Antigen processing and presentation\" similarly as that of RA.\n\nConclusionOA can be clearly classified into two distinguished subtypes with blood transcriptome, which have important significance on the development of precise OA therapeutics.

bioinformatics

Cell atlas of human uterus

The human uterus is a highly dynamic tissue that undergoes repeated damage repair and regeneration during the menstrual cycle, which make it ideal model to study tissue regeneration and pathological process. Stem/progenitors were speculated to be involved in the regeneration of endometrial epithelial and pathogenesis of endometriosis. But the identity, microenvironment and regulatory mechanisms of the uterus epithelial stem/progenitors in vivo remain unclear. Here, we dissected the cell heterogeneities of the full-thickness human uterus epithelial cells (11 clusters), stroma cells (6 clusters), endothelial cells (5 clusters), smooth muscle cells (2 clusters), myofibroblasts (2 clusters) and immune cells (6 clusters) from 2735 single cell by single cell RNA-seq. Further analysis identified a unique ciliated epithelial cell cluster showing characteristics of stem/progenitors with properties of epithelial-mesenchymal transition (EMT) that mainly localized in the upper functionalis of the endometrium. Ordering the cell subpopulations along the pseudo-space revealed cell clusters possess cellular states of stress, inflammation and apoptosis in the upper functionalis cellular ecosystem of the endometrium. Connectivity map between the human uterus subpopulations revealed potential inflammatory (cytokines and chemokines) and developmental (WNT, FGF, VEGF) signals within the upper functionalis cellular ecosystem of the endometrium, especially from other epithelial clusters, regulating cell plasticity of the EMT-epithelial clusters. This study reconstructed the heterogeneities, space-specific distribution and connectivity map of human uterus atlas, which would provide insight in the regeneration of uterus endometria and reference for the pathogenesis of uterus.

cell biology

LinearFold: Linear-Time Prediction of RNA Secondary Structures

Predicting the secondary structure of an RNA sequence with speed and accuracy is useful in many applications such as drug design. The state-of-the-art predictors have a fundamental limitation: they have a run time that scales cubically with the length of the input sequence, which is slow for longer RNAs and limits the use of secondary structure prediction in genome-wide applications. To address this bottleneck, we designed the first linear-time algorithm for this problem. which can be used with both thermodynamic and machine-learned scoring functions. Our algorithm, like previous work, is based on dynamic programming (DP), but with two crucial differences: (a) we incrementally process the sequence in a left-to-right rather than in a bottom-up fashion, and (b) because of this incremental processing, we can further employ beam search pruning to ensure linear run time in practice (with the cost of exact search). Even though our search is approximate, surprisingly, it results in even higher overall accuracy on a diverse database of sequences with known structures. More interestingly, it leads to significantly more accurate predictions on the longest sequence families in that database (16S and 23S Ribosomal RNAs), as well as improved accuracies for long-range base pairs (500+ nucleotides apart).

bioinformatics

Acute and chronic toxicity assessment of benzylpenicillin G residue in cooked meat

The current level of penicillin use and its persisting residues in livestock is potentially concerning; the toxicity of penicillin residues in heat-treated animal food products (HAFP) is yet to be elucidated. In this study, the acute and chronic toxicity of benzylpenicillin G (BPG) residues in HAFP was investigated in a mouse model. The calculated LD50 of BPG heated to cooking temperature (BPHCT) was 933.04 mg kg-1 [b.w.] intraperitoneally corresponding to 3.75 times lower than its prototype. Mice fed on the experimental diet containing heat-treated beef with high BPG levels for 6 months displayed a reduction in body weight and altered serum values indicating for liver and renal function. Further, the organ ratios of intestinal and spleen were increased. Histopathological changes were observed in the liver, lung and parenchyma testis tissue. BPHCT residue induced sperm aberration and micronucleated polychromatic erythrocytes formation. Present results indicate that prolonged exposure of BPHCT at higher levels of residue might have an impact on public health. Importantly the toxic concentrations of BPHCT are relatively high compared with levels that would result from the degradation of antibiotic residues in meat from animals that have received a therapeutic dose of BPG.

pharmacology and toxicology

A high-throughput analysis method of microdroplet PCR coupled with fluorescence spectrophotometry

Here we report a novel microdroplet PCR method combined with fluorescence spectrophotometry (MPFS), which allows for qualitative, quantitative and high -throughput detection of multiple DNA targets. In this study, each pair of primers was labeled with a specific fluorophore. Through microdroplet PCR, a target DNA was amplified and labeled with the same fluorophore. After products purification, the DNA products tagged with different fluorophores could be analyzed qualitatively by the fluorescent intensity determination. The relative fluorensence unit was also measured to construct the standard curve and to achieve quantitative analysis. In a reaction, the co -amplified products with different fluorophores could be simultaneously analyzed to achieve high -throughput detection. We used four kinds of GM maize as a model to confirm this theory. The qualitative results revealed high specificity and sensitivity of 0.5% (w / w). The quantitative results revealed that the limit of detection was 103copies and with good repeatability. Moreover, reproducibility assay were further performed using four foodborne pathogenic bacteria. Consequently, the same qualitative, quantitative and high-throughput results were confirmed as the four GM maize.

biochemistry