Cyanobacterial blooms in Lake Taihu: Temporal trends and potential drivers.

Lake Taihu, an inland lake, frequently experiences Cyanobacterial blooms that have historically posed severe threats to its aquatic ecosystem. Combining field observations and satellite remote-sensed data, factors that influence algal bloom intensity in Lake Taihu over an eight-year period, from 2016 to 2023, are examined, and changes in phytoplankton community composition, climate, water quality, economic activities, and food web dynamics are reported. Sentinel-2 MSI data analysis reveals a dramatic decrease in Cyanobacterial blooms in 2023, with a reduction in the annual maximum bloom area of 76.90 % from 2016 values. From 2016 to 2022, the ratio of Cyanobacteria to other phytoplankton ranged 82.09 %-98.29 %, but in 2023, this dropped to 60.98 %. Concurrently, Cyanobacteria density dropped to an historic low of 2.29 × 107 cells/L (16.4 % of 2021 peak values). Redundancy and random forest analyses indicated that nitrogen has a greater influence on phytoplankton than phosphorus, with temperature and permanganate index being the important parameters to affect phytoplankton community structure. We attribute the decrease in Cyanobacterial blooms in Lake Taihu in 2023 to be largely caused by shifts in phytoplankton community structure, particularly the sharp decline in Microcystis sp. density, a genus often linked to bloom formation. Meteorological conditions such as reduced rainfall and wind speed during the winter and spring of 2023 also contributed to diminishing Cyanobacterial blooms. Ongoing improvements in water quality, reduced economic activities because of pandemic restrictions, and implementation of a fishing ban since 2020 have likely further contributed to reductions in bloom frequency. These results improve our understanding of the processes that affect algal blooms in Lake Taihu, and potentially other eutrophic inland lakes.

Prognostic and chemotherapeutic response prediction by proliferation essential gene signature: Investigating POLE2 in bladder cancer progression and cisplatin resistance.

Background: Bladder cancer (BLCA) is the most common genitourinary malignancy. Proliferation essential genes (PEGs) are crucial to the survival of cancer cells. This study aimed to build a PEG signature to predict BLCA prognosis and treatment efficacy. Methods: BLCA PEGs and differentially expressed PEGs were identified using DepMap and TCGA-BLCA datasets, respectively. Based on the prognostic analysis of the differentially expressed PEGs, a PEG model was constructed. Subsequently, we analyzed the relationship between the PEG signature and prognosis of BLCA patients as well as their response to chemotherapy. Finally, we performed random forest analysis to target and functional experiments to validate the most significant PEG which is associated with BLCA progression. CCK-8, invasion, migration, and chemosensitivity assays were performed to assess effects of gene knockdown on BLCA cell proliferation, invasion and migration abilities, and cisplatin chemosensitivity. Results: We screened 10 prognostic PEGs from 201 differentially expressed PEGs and used them to construct a PEG signature model. Patients with high PEG signature score (PEGs-high) exhibited worse OS and lower sensitivity to chemotherapy than those with PEGs-low. We also found significant correlations between the PEG score and previously defined BLCA molecular subtypes. This suggests that the PEG score may effectively predict the molecular subtypes which have distinct clinical outcomes. Random forest analysis revealed that POLE2 (DNA polymerase epsilon subunit 2) was the most significant PEG differentiating BLCA tissue and normal tissue. Bioinformatic analysis and an immunohistochemistry staining assay confirmed that POLE2 was significantly up-regulated in tumor tissues and was associated with poor survival in BLCA patients. Moreover, POLE2 knockdown inhibited the ability of cell clone formation, proliferation, invasion, immigration and IC50 of cisplatin. Conclusion: The PEG signature acts as a potential predictor for prognosis and chemotherapy response in BLCA patients. POLE2 is a key PEG and plays a remarkable role in promoting the malignant progression and cisplatin resistance of BLCA.

Expansion of Betatorquevirus and/or Gammatorquevirus in Patients with Severe Clinical Outcomes of the Liver Diseases.

Anellovirus (AV) is a ubiquitous virus in the human population. Individuals can be infected with multiple AV genera and species to form a heterogeneous repertoire, termed the anellome. Using advanced methods, we examined the anellomes from 12 paired serum and liver samples, as well as 2701 subjects with different clinical diagnoses. Overall, anellomes are remarkably individualized, with significant among-group differences (Kruskal-Wallis test p = 6.6 × 10-162 for richness and p = 7.48 × 10-162 for Shannon entropy). High dissimilarity scores (beta diversity) were observed between patient groups, except for paired serum and liver samples. At the population level, the relative abundance of combinational AV genus Betatorquevirus (torque teno mini viruses, TTMV), and Gammatorquevirus (torque teno midi viruses, TTMDV) exhibited an exponential distribution with a low bound point at 32%. Defined by this value, the AV TTMV/TTMDV-expanded anellome was significantly enriched among patients with acute liver failure (31.7%) and liver transplantation (40.7%), compared with other patient groups (χ2 test: p = 4.1 × 10-8-3.2 × 10-3). Therefore, anellome heterogeneity may be predictive of clinical outcomes in certain diseases, such as liver disease. The consistency of anellome between paired serum and liver samples indicates that a liquid biopsy approach would be suitable for longitudinal studies to clarify the causality of the AV TTMV/TTMDV-expanded anellome in the outcomes of liver disease.

Use of Immunohistochemical p53 Mutant-Phenotype in Diagnosis of High-Grade Dysplasia of Esophageal Squamous Epithelia.

BACKGROUND: Mild cellular atypia of esophageal squamous epithelial dysplasia has a risk of progressing to cancer that poses great confusion for pathological diagnosis. There is no research on the diagnosis and differential diagnosis of esophageal squamous dysplasia by the expression of immunohistochemical (IHC) p53. The study aims to conduct a graded diagnosis of esophageal squamous epithelial hyperplasia by combining p53 expressions and microscopic histomorphological characteristics. METHODS: The study was conducted from January 2021 to January 2022 and included a total of 208 cases including 262 specimens with atypical hyperplasia or dysplasia of squamous epithelia discovered by esophageal mucosal biopsy. HE staining was used to grade the epithelial hyperplasia degree, and all cases underwent p53 IHC evaluation. RESULTS: Benign lesions: we did not find any p53 IHC mutant-phenotype (0/12 cases) in 12 cases of esophagitis. We found 10 cases (10/80 cases) of p53 IHC mutant-phenotype in 80 cases of low-grade dysplasia, and 158 cases (158/170 cases) of p53 IHC mutant-phenotype of high-grade lesions in 170 cases of high-grade dysplasia and early cancer based on the χ2 test results. We found statistically significant differences in p53 IHC mutant-phenotype between the high-grade squamous epithelial lesions and benign lesions. The sensitivity and specificity of p53 in detecting high-grade squamous epithelial lesions were 92.9% and 89.1%, respectively. The positive predictive value was 94.0%, and the negative predictive value was 87.2%. CONCLUSION: In this study, we found that p53 IHC had high sensitivity and specificity in detecting high-grade esophageal squamous epithelial lesions. Therefore, it has potential to be used as a routine item in pathological detection for auxiliary risk stratification of esophageal squamous epithelial lesions.

DPP6 and MFAP5 are associated with immune infiltration as diagnostic biomarkers in distinguishing uterine leiomyosarcoma from leiomyoma.

Objective: Uterine leiomyosarcoma (ULMS) is the most common subtype of uterine sarcoma and is difficult to discern from uterine leiomyoma (ULM) preoperatively. The aim of the study was to determine the potential and significance of immune-related diagnostic biomarkers in distinguishing ULMS from ULM. Methods: Two public gene expression profiles (GSE36610 and GSE64763) from the GEO datasets containing ULMS and ULM samples were downloaded. Differentially expressed genes (DEGs) were selected and determined among 37 ULMS and 25 ULM control samples. The DEGs were used for Gene Ontology (GO), Kyoto Encyclopaedia of Genes and Genomes (KEGG) and Disease Ontology (DO) enrichment analyses as well as gene set enrichment analysis (GSEA). The candidate biomarkers were identified by least absolute shrinkage and selection operator (LASSO) and support vector machine recursive feature elimination (SVM-RFE) analyses. The receiver operating characteristic curve (ROC) was applied to evaluate diagnostic ability. For further confirmation, the biomarker expression levels and diagnostic value in ULMS were verified in the GSE9511 and GSE68295 datasets (12 ULMS and 10 ULM), and validated by immunohistochemistry (IHC). The CIBERSORT algorithm was used to calculate the compositional patterns of 22 types of immune cells in ULMS. Result: In total, 55 DEGs were recognized via GO analysis, and KEGG analyses revealed that the DEGs were enriched in nuclear division, and cell cycle. The recognized DEGs were primarily implicated in non-small cell lung carcinoma and breast carcinoma. Gene sets related to the cell cycle and DNA replication were activated in ULMS. DPP6 and MFAP5 were distinguished as diagnostic biomarkers of ULMS (AUC = 0.957, AUC = 0.899, respectively), and they were verified in the GSE9511 and GSE68295 datasets (AUC = 0.983, AUC = 0.942, respectively). The low expression of DPP6 and MFAP5 were associated with ULMS. In addition, the analysis of the immune microenvironment indicated that resting mast cells were positively correlated with DPP6 and MFAP5 expression and that eosinophils and M0 macrophages were negatively correlated with DPP6 expression (P<0.05). Conclusion: These findings indicated that DPP6 and MFAP5 are diagnostic biomarkers of ULMS, thereby offering a novel perspective for future studies on the occurrence, function and molecular mechanisms of ULMS.

Rapid and ultra-trace levels analysis of 33 antibiotics in water by on-line solid-phase extraction with ultra-performance liquid chromatography-tandem mass spectrometry.

A method was developed for the determination of 33 antibiotics belonging to 4 different antibiotic groups, including sulfonamides (16), fluoroquinolones (12), macrolides (1), and tetracyclines (4) in water samples using on-line solid-phase extraction-ultra performance liquid chromatography-electrospray ionization tandem mass spectrometry (on-line SPE-UPLC-MS/MS). The enrichment and analysis conditions were optimized for the determination of trace concentrations (nanogram per liter). Aliquots of the water samples (5 mL) were filtered through a membrane and enriched on an on-line polymeric column with hydrophilic-lipophilic balance (HLB). The analyte was eluted by the mobile phase during on-line SPE and separated on an Acquity BEH130 column, detected by tandem mass spectrometry, and quantified using an external standard method. The optimization of the analytical methods was discussed, which included optimization of pH of the sample, filtration membrane, Na2EDTA, chromatographic column, formic acid and aqueous ammonia in mobile phase. The detection limit for all test compounds by this method was in the range of 0.2-1.5 ng/L, with recoveries of 76.6-118%. The precision of the method, as indicated by the relative standard deviation, was 2.4-7.9%. Results of analysis of surface water samples demonstrated the ability of the proposed method to analyze ultra-trace levels of antibiotics, without the need for complex manual pretreatment.

Within-host quantitation of anellovirus genome complexity from clinical samples.

Anellovirus (AV) is a ubiquitous and diverse virus in the human population. An individual can be infected with multiple AV genera and species that form a heterogeneous repertoire, called the anellome. Due to its exceptional genetic diversity, efficient evaluation of anellome complexity remains a methodological challenge. In the current study, AV genome was first enriched from patient serum samples through two-phase rolling circle amplification. Following Illumina sequencing, anellome was analyzed with an advanced bioinformatics pipeline, including read extraction at three similarity levels, de novo assembly, species assignment, and determination of relative abundance among AV variants. The method was validated in the mock sample and then applied to 21 hepatitis C virus (HCV) patients with and without hepatocellular carcinoma (HCC). Overall, there was a large variance regarding AV richness, ranging from 2 to 51 AV species. In contrast to HCV patients without HCC, HCC incidence was associated with reduced richness (12.6 ± 14.4 vs. 35.4 ± 13.6, p = 0.001) and Shannon entropy (0.4 ± 0.34 vs. 0.61 ± 0.12, p = 0.095) at the AV species level. Interestingly, AV genus beta and gamma expanded in the anellome in 7 of 10 HCC patients. These observations shed light on the potential association between anellome and HCC incidence in patients with chronic HCV infection. The method presented here represents a valuable tool to investigate the role of anellome in human health and disease.

Influencing factors of lung cancer in nonsmoking women: systematic review and meta-analysis.

BACKGROUND: Epidemiological studies have shown that some factors other than smoking may affect the risk of lung cancer in women, but the results are controversial. We conducted a meta-analysis to summarize the influencing factors of lung cancer in nonsmoking women. METHODS: Both English and Chinese databases were searched for publications from 1990 to 2020. All included studies were assessed according to the Newcastle-Ottawa Scale (NOS). The pooled odds ratios (ORs) and 95% confidence interval (CI) of influential factors were analyzed using the meta-analysis method, and the publication bias and sensitivity were analyzed. RESULTS: Among the five categories, the pooled OR of cooking factors category was the highest. Among 42 influencing factors, there were frequent fried food (OR = 2.42, 95% CI: 1.73-3.38) and long menstrual cycle (0.54, 95% CI: 0.39-0.75). A positive association of history of lung diseases/family lung/all cancer with lung cancer among Asian nonsmoking women (1.82, 95% CI: 1.60-2.07). Unlike other regions, cooking factors were the main risk factor for lung cancer in Asian. CONCLUSION: The meta-analysis suggests that cooking habits, diet, passive smoking, history of cancer and lung disease, and female reproduction are related to lung cancer in nonsmoking women. However, additional studies are warranted to extend this finding.

Oral, Nasal, and Gut Microbiota in Parkinson's Disease.

Parkinson's disease (PD) is the second most frequently diagnosed neurodegenerative disease. The purpose of this study was to investigate the link between microbiota composition in important mucosal interfaces (oral, nasal, and intestinal) and PD. Sequencing was undertaken of the V4-V5 region of the 16S ribosomal RNA (rRNA) gene of the microbiome from the oral cavity, nasal cavity, and gut of 91 PD patients and 91 healthy controls. Significant differences were found in microbiota composition in the oral cavity and gut, but not the nasal cavity, between PD patients and healthy controls after adjusting for age, gender, and body mass index (BMI). More genera in the oral cavity were significantly positively correlated with clinical characteristics, such as the HAMA and HAMD rating scales. The taxa c_Clostridia, o_Clostridiales, and f_Ruminococcaceae in the gut microbiota were associated with weight and MMSE score. Furthermore, as a result of dysbiosis, there was an enrichment of ion channel-, oxidative phosphorylation-, and carbohydrate metabolism-related pathways in the oral cavity and glycolysis/gluconeogenesis- and propanoate metabolism-related pathways in the intestine. Changes in these pathways can influence metabolism and inflammation, thereby contributing to PD pathogenesis. In addition, several subnetworks containing differentially abundant microbiota in the oral cavity and gut samples from PD patients may regulate microbial composition and function in PD. Overall, our results indicate that oral and gut dysbiosis may affect PD progression and provide a basis for understanding the pathogenesis of PD and identifying potential therapeutic targets for the treatment of this disease.

Altered Actinobacteria and Firmicutes Phylum Associated Epitopes in Patients With Parkinson's Disease.

Recent evidence suggests that inflammation was participated in the pathogenesis of PD, thus, to understand the potential mechanism of gut microbiota in the pathogenesis of Parkinson's disease (PD), we performed a metagenomic analysis of fecal samples from PD patient and controls. Using a two-stage metagenome-wide association strategy, fecal DNA samples from 69 PD patients and 244 controls in three groups (comprising 66 spouses, 97 age-matched, and 81 normal samples, respectively) were analyzed, and differences between candidate gut microbiota and microbiota-associated epitopes (MEs) were compared. In the study, 27 candidate bacterial biomarkers and twenty-eight candidate epitope peptides were significantly different between the PD patients and control groups. Further, enriched 4 and 13 MEs in PD were positively associated with abnormal inflammatory indicators [neutrophil percentage (NEUT.1), monocyte count/percentage (MONO/MONO.1), white blood cell count (WBC)] and five candidate bacterial biomarkers (c_Actinobacteria, f_Bifidobacteriaceae, g_Bifidobacterium, o_Bifidobacteriales, p_Actinobacteria) from Actinobacteria phylum, and they were also positively associated with histidine degradation and proline biosynthesis pathways, respectively. Additionally, enriched 2 MEs and 1 ME in PD were positively associated with above inflammatory indicators and two bacteria (f_Lactobacillaceae, g_Lactobacillus) from Firmicutes phylum, and they were also positively associated with pyruvate fermentation to propanoate I and negatively associated with isopropanol biosynthesis, respectively. Of these MEs, two MEs from GROEL2, RPSC were derived from Mycobacterium tuberculosis, triggered the T cell immune response, as previously reported. Additionally, other candidate epitope peptides derived from Mycobacterium tuberculosis and Mycobacterium leprae may also have potential immune effects in PD. In all, the altered MEs in PD may relate to abnormalities in immunity and glutamate and propionate metabolism, which furthers our understanding of the pathogenesis of PD.

The Effects of Tai Chi Exercise Among Adults With Chronic Heart Failure: An Overview of Systematic Review and Meta-Analysis.

Background: Tai chi (TC) is a popular form of exercise among adults with chronic heart failure (CHF), yet services are greatly underutilized. The aim of the current study was to identify and summarize the existing evidence and to systematically determine the clinical effectiveness of Tai Chi in the management of CHF using a systematic overview. Methods: Both English and Chinese databases were searched for systematic reviews (SRs)/meta-analyses (MAs) on TC for CHF from their inception to June 2020. The methodological quality, reporting quality, and risk of bias of SRs/MAs were assessed using Assessing the Methodological Quality of Systematic Reviews 2 (AMSTAR-2), the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist, and Risk of Bias in Systematic reviews (ROBIS), respectively. The evidence quality of outcome measures was assessed by the Grades of Recommendations, Assessment, Development and Evaluation (GRADE). Results: Six SRs/MAs using a quantitative synthesis to assess various outcomes of TC in CHF were included in this overview. The methodological quality, reporting quality and risk of bias of the SRs/MAs and the evidence quality of the outcome measures are generally unsatisfactory. The limitations of the past SRs/MAs included the lack of either the protocol or registration, the list of excluded studies, and the computational details of meta-analysis were inadequately reported. The critical problems were that qualitative data synthesis relied on trials with small sample sizes and critical low quality. Conclusions: TC may be a promising complementary treatment for CHF. However, further rigorous and comprehensive SRs/MAs and RCTs are required to provide robust evidence for definitive conclusions.

Risk factors for chemotherapy-induced vomiting after general anesthesia in children with retinoblastoma: a retrospective study.

BACKGROUND: The chemotherapy-induced vomiting (CIV) severely affects the daily function, nutritional status, treatment compliance, therapeutic efficacy, curability, and the quality of life of patients. The aim of this study was to find the risk factors for CIV after general anesthesia in patients with retinoblastoma (RB). METHODS: A retrospective review of the hospital records of children with RB, who underwent chemotherapy between January 2017 and December 2019, was conducted at our hospital. RESULTS: Data of a total of 803 children with RB were reviewed. The incidence of CIV in children with RB was 19.30%. Univariate analysis showed statistically significant differences in age, height, weight, chemotherapy regimen, anesthesia dose, duration of surgery and general anesthesia, platelet count, platelet distribution width, lymphocytes, and indirect bilirubin between patients with and without vomiting (P<0.05). Multivariate logistic regression analysis showed that the main predictors of CIV in children with RB included older age [odds ratio (OR), 1.32; 95% confidence interval (CI): 1.11-1.56; P<0.01], low platelet count (OR, 0.997; 95% CI: 0.995-0.999; P<0.05), and chemotherapy regimen (intravenous chemotherapy versus intra-arterial chemotherapy; OR, 0.47; 95% CI: 0.29-0.76; P<0.01). CONCLUSIONS: This study revealed age, chemotherapy regimen, and platelet count as risk factors of CIV after general anesthesia in children with RB. Younger age and higher platelet count were protective factors for CIV. Compared with intravenous chemotherapy, the incidence of CIV was lower than that of intra-arterial chemotherapy. Although these factors cannot be modified, they can predict whether a patient may experience vomiting, assisting medical staff to formulate measures and intervenes in advance. KEYWORDS: Retinoblastoma (RB); chemotherapy-induced vomiting (CIV); general anesthesia; multivariate analysis; risk factors.

A novel target enrichment strategy in next-generation sequencing through 7-deaza-dGTP-resistant enzymatic digestion.

OBJECTIVE: Owing to the overwhelming dominance of human and commensal microbe sequences, low efficiency is a major concern in clinical viral sequencing using next-generation sequencing. DNA composed of 7-deaza-2'-deoxyguanosine 5'-triphosphate (c7dGTP), an analog of deoxyguanosine triphosphate (dGTP), is resistant to selective restriction enzymes. This characteristic has been utilized to develop a novel strategy for target enrichment in next-generation sequencing. RESULTS: The new enrichment strategy is named target enrichment via enzymatic digestion in next-generation sequencing (TEEDseq). It combined 7-deaza-2'-deoxyguanosine 5'-triphosphate (c7dGTP)-involved primer extension, splinter-assisted intracellular cyclization, c7dGTP)-resistant enzymatic digestion, and two-phase rolling cycle amplification. We first estimated c7dGTP for its efficiency in PCR amplification and its resistance to three restriction enzymes, AluI, HaeIII, and HpyCH4V. We then evaluated TEEDseq using a serum sample spiked with a 1311-bp hepatitis B virus (HBV) fragment. TEEDseq achieved an HBV on-target rate of 3.31 ± 0.39%, which was equivalent to 454× the enrichment of direct Illumina sequencing. Therefore, the current study has provided a concept proof for TEEDseq as an alternative option for clinical viral sequencing that requires an enrichment in next-generation sequencing.

Genome-wide capture sequencing to detect hepatitis C virus at the end of antiviral therapy.

BACKGROUND: Viral relapse is a major concern in hepatitis C virus (HCV) antiviral therapy. Currently, there are no satisfactory methods to predict viral relapse, especially in the era of direct acting antivirals in which the virus often quickly becomes undetectable using PCR-based approaches that focus on a small viral region. Next-generation sequencing (NGS) provides an alternative option for viral detection in a genome-wide manner. However, owing to the overwhelming dominance of human genetic content in clinical specimens, direct detection of HCV by NGS has a low sensitivity and hence viral enrichment is required. METHODS: Based on template-dependent multiple displacement amplification (tdMDA), an improved method for whole genome amplification (Wang et al., 2017. Biotechniques 63, 21-27), we evaluated two strategies to enhance the sensitivity of NGS-based HCV detection: duplex-specific nuclease (DSN)-mediated depletion of human sequences and HCV probe-based capture sequencing. RESULTS: In DSN-mediated depletion, human sequences were significantly reduced in the two HCV serum samples tested, 65.3% → 55.6% → 33.7% (#4727) and 68.6% → 56% → 21% (#4970), respectively for no normalization, self- and driver-applied normalization. However, this approach was associated with a loss of HCV sequences perhaps due to its micro-homology with the human genome. In capture sequencing, HCV-mapped sequencing reads occupied 96.8% (#4727) and 22.14% (#4970) in NGS data, equivalent to 1936x and 7380x enrichment, respectively. Capture sequencing was then applied to ten serum samples collected at the end of HCV antiviral therapy. Interestingly, the number of HCV-mapped reads was significantly higher in relapsed patients (n = 5) than those from patients with sustained virological response (SVR) (n = 5), 102.4 ± 72.3 vs. 2.6 ± 0.55, p = 0.014. CONCLUSIONS: Our data provides concept evidence for a highly sensitive HCV detection by capture sequencing. The abundance difference of HCV sequencing reads at the end of HCV antiviral therapy could be applied to predict treatment outcomes.

In-depth serum virome analysis in patients with acute liver failure with indeterminate etiology.

In clinical virome research, whole-genome/transcriptome amplification is required when starting material is limited. An improved method, named "template-dependent multiple displacement amplification" (tdMDA), has recently been developed in our lab (Wang et al. in BioTechniques 63:21-25. https://doi.org/10.2144/000114566, 2017). In combination with Illumina sequencing and bioinformatics pipelines, its application in virome sequencing was explored using a serum sample from a patient with chronic hepatitis C virus (HCV) infection. In comparison to an amplification-free procedure, virome sequencing via tdMDA showed a 9.47-fold enrichment for HCV-mapped reads and, accordingly, an increase in HCV genome coverage from 28.5% to 70.1%. Eight serum samples from acute patients liver failure (ALF) with or without known etiology were then used for virome sequencing with an average depth at 94,913x. Both similarity-based (mapping, NCBI BLASTn, BLASTp, and profile hidden Markov model analysis) and similarity-independent methods (machine-learning algorithms) identified viruses from multiple families, including Herpesviridae, Picornaviridae, Myoviridae, and Anelloviridae. However, their commensal nature and cross-detection ruled out an etiological interpretation. Together with a lack of detection of novel viruses in a comprehensive analysis at a resolution of single reads, these data indicate that viral agents might be rare in ALF cases with indeterminate etiology.

Full annotation of serum virome in Chinese blood donors with elevated alanine aminotransferase levels.

BACKGROUND: A serum alanine aminotransferase (ALT) test is currently demanded for blood donation in China. One of the major reasons to include such a test is possible etiology of known or unknown hepatotropic viruses. However, this hypothesis has never been examined convincingly. STUDY DESIGN AND METHODS: The study recruited 90 Chinese blood donors that were divided into three groups based on their ALT values. Serum virome from these donors was explored using a metagenomics approach with enhanced sensitivity resolved at single sequencing reads. RESULTS: Anellovirus and pegivirus C (GBV-C) were detected among these donors. None of them were found solely in donors with abnormal liver enzyme. Anellovirus was highly prevalent (93.3%) and the co-infection with multiple genera (alpha, beta, and gammatorquevirus) were more common in the donors with normal ALT values in comparison to those with elevated ALT (single/double/triple Anellovirus genera, 1/3/24 vs. 7/7/14 or 6/7/13, p = 0.009). For unmapped reads that accounted for 15 ± 14.9% of the data, similarity-based (BLASTN, BLASTP, and HMMER3) and similarity-independent (k-mer frequency) analysis identified several circular rep encoding ssDNA (CRESS-DNA) genomes. Direct PCR testing indicated these genomes were likely reagent contaminants. CONCLUSION: Viral etiology is not responsible for elevated ALT levels in Chinese blood donors. The ALT test, if not abandoned, should be adjusted for its cutoff in response to donor shortage in China.

[Rapid determination of ultra-trace levels of atrazine in surface water by on line solid phase extraction coupled with ultra-performance liquid chromatography-tandem mass spectrometry].

A method for the determination of ultra-trace atrazine in surface water was developed based on on line solid phase extraction-ultra performance liquid chromatography-tandem mass spectrometry (on line SPE-UPLC-MS/MS). The water sample was directly injected into an on line SPE system after filtering using a 0.22 µm filter membrane. An HLB Direct Connect HP column was used for the enrichment and purification of the water sample and eluted using a methanol solution. The analyte was separated on an Acquity BEH 130 column, and then detected by tandem mass spectrometry. The analyte was quantified with external standard method. There was a good linear relationship in the range of 1.0-5000 ng/L. The correlation coefficient (r) was 0.9989. The method detection limit was 0.2 ng/L. The recoveries of atrazine ranged from 83.0% to 105.1%. The relative standard deviation was 1.6%-5.3% (n=7), which met the requirements of trace analysis. The method is sensitive, fast and effective, and it is suitable for the determination of atrazine in surface water. It is important to ensure the safety of the water environment, provide timely pollution information, and effectively respond to environmental emergencies.

MiR-147b inhibits cell viability and promotes apoptosis of rat H9c2 cardiomyocytes via down-regulating KLF13 expression.

Recently, microRNAs (miRNAs) have been shown to involve in the process of heart failure. This study aims to investigate the functional role of miR-147b in rat H9c2 cardiomyocytes and explore the underlying molecular mechanisms. Cell viability of H9c2 cells was detected by MTT assay. Cell apoptosis was detected by flow cytometry. Expression of miR-147b and KLF13 mRNA was detected by quantitative real-time PCR. The relationship between miR-147b and KLF13 was verified by dual-luciferase reporter assay. Protein levels were detected by western blot analysis. It was found that H2O2 inhibited cell viability and promoted cell apoptosis of H9c2 cells in a concentration-dependent manner. MiR-147b overexpression suppressed cell viability and increased apoptosis in H9c2 cells, while knock-down of miR-147b increased cell viability and reduced apoptosis in H2O2-treated H9c2 cells. Luciferase reporter assay and in vitro functional assay showed that KLF13 was a downstream target of miR-147b, and KLF13 knock-down suppressed cell viability and induced apoptosis in H9c2 cells. Enforced expression of KLF13 restored the effects of miR-147b overexpression on cell viability and apoptosis in H9c2 cells. MiR-147b modulated the expression levels of apoptosis-related proteins, and the effects of miR-147b overexpression on apoptosis-related proteins levels were prevented by enforced expression of KLF13 in H9c2 cells. The in vivo experiments showed that miR-147b was up-regulated, and KLF13 was down-regulated in the myocardial tissues from rats with chronic heart failure. Collectively, miR-147b inhibits viability and promotes cell apoptosis by targeting KLF13 in H9c2 cells, which may be associated with the pathogenesis of heart failure.

[Determination of microcystins in algal bloom samples by ultra performance liquid chromatography-tandem mass spectrometry and elimination of their matrix effects].

A rapid and simple method was commonly used for the determination of microcystins by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The reliability, accuracy and sensitivity of LC-MS/MS determination were affected by the matrix effect because of the complex matrices in algal bloom samples. In this study, the matrix interference and matrix effect problems were effectively reduced or eliminated by diluting samples, optimizing gradient elution programs, and reducing injection volumes. The correlation coefficients (r2) of the seven microcystins were ≥ 0.99. The limits of detection and limits of quantification ranged from 0.064 µ g/L to 0.103 µ g/L and 0.213 µ g/L to 0.343 µ g/L, respectively. Algal bloom samples were determined by diluting 10 times and injecting 5 µ L of sample volume. The method provides some references for the determination of microcystins. It is of great significance for ensuring the safety of drinking water source.

Uridine adenosine tetraphosphate acts as a proangiogenic factor in vitro through purinergic P2Y receptors.

Uridine adenosine tetraphosphate (Up4A), a dinucleotide, exerts vascular influence via purinergic receptors (PR). We investigated the effects of Up4A on angiogenesis and the putative PR involved. Tubule formation assay was performed in a three-dimensional system, in which human endothelial cells were cocultured with pericytes with various Up4A concentrations for 5 days. Expression of PR subtypes and angiogenic factors was assessed in human endothelial cells with and without P2Y6R antagonist. No difference in initial tubule formation was detected between Up4A stimulation and control conditions at day 2 In contrast, a significant increase in vascular density in response to Up4A was observed at day 5 Up4A at an optimal concentration of 5 µM promoted total tubule length, number of tubules, and number of junctions, all of which were inhibited by the P2Y6R antagonist MRS2578. Higher concentrations of Up4A (10 µM) had no effects on angiogenesis parameters. Up4A increased mRNA level of P2YRs (P2Y2R, P2Y4R, and P2Y6R) but not P2XR (P2X4R and P2X7R) or P1R (A2AR and A2BR), while Up4A upregulated VEGFA and ANGPT1, but not VEGFR2, ANGPT2, Tie1, and Tie2. In addition, Up4A increased VEGFA protein levels. Transcriptional upregulation of P2YRs by Up4A was inhibited by MRS2578. In conclusion, Up4A is functionally capable of promoting tubule formation in an in vitro coculture system, which is likely mediated by pyrimidine-favored P2YRs but not P2XRs or P1Rs, and involves upregulation of angiogenic factors.