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Since the outbreak of the COVID-19 global pandemic in 2019, monitoring COVID-19 infection status and trend through wastewater, known as wastewater-based epidemiology (WBE), has been widely used in many countries and regions. WBE consists of five steps: wastewater sample collection, viral concentration, viral nucleic acid extraction, quantification of virus using quantitative RT-PCR, and dissemination of the wastewater surveillance results. This method could be used for early warning of COVID-19 outbreak in a population, monitoring COVID-19 distributions and epidemic trend, prediction of COVID-19 prevalence rate, understanding of temporal trend of SARS-COV-2 variants, and simultaneous surveillance of multiple pathogens. WBE and clinical surveillance can be used concurrently and the former is a good complement to the latter. [ABSTRACT FROM AUTHOR]

Objective To optimize the extraction method of total RNA from pancreatic cancer and adjacent tissues, and provide high-quality experimental samples for the pathogenesis of pancreatic-related diseases. Methods The pretreatment of pancreatic cancer and paracancerous tissues was accomplished through shredding, RNase-free washing and RNase inhibition. RNA was isolated by liquid nitrogen grinding and trizol-chloroform extraction. The integrity of RNA was identified by agarose gel electrophoresis and bioanalyzer. With the same amount of RNA as the reverse transcription template, oligo dT primers were used for reverse transcription of messenger RNA (mRNA); stem-loop structure primers were used to reverse transcription of microRNA (miRNA). The expression levels of mRNA and miRNA were detected by quantitative RT-PCR. Compared with conventional methods, RNA samples extracted by the optimized method had a lower degradation degree and higher integrity. Results Compared with pancreatic cancer tissue, RNA in adjacent tissue is more easily degraded, and the expression level of mRNA tends to decrease. However, there is no significant difference in miRNA expression between pancreatic cancer and adjacent tissue. Conclusions Pretreatment of pancreatic cancer and adjacent tissues could reduce the RNA degradation, and provide high-quality experimental samples for RNA investigation and high experimental accuracy. [ABSTRACT FROM AUTHOR]

Objective To observe the impact of serum miRNA-128a and miRNA-128b expression on early diagnosis and prognosis in patients with gastric cancer. Methods One hundred and eighteen patients with gastric cancer diagnosed in Huashan Hospital,Fudan University from Jan.2015 to Jan.2017 were selected as the gastric cancer group.Seventy-five patients with gastric polyps by pathological diagnosis and 45 healthy people were selected as gastric polyps group and healthy control.Quantitative RT-PCR was used to detect the expression levels of serum miRNA-128a and miRNA-128b in each group.The relation among serum miRNA-128a and miRNA-128b levels,clinic pathological parameters in gastric cancer patients and prognosis was observed,and their efficacy of diagnose and predicting death within 2 years was also observed. Results The serum miRNA-128a expression in gastric cancer group was significantly higher than that in gastric polyp group (q=26.388,P<0.01) and healthy control (q=32.195,P<0.01),the expression in gastric polyp group was significantly higher compared with the healthy control (q=7.198,P<0.01),and after operation the expression level was significantly lower than that before operation (t=14.321,P<0.01).The serum miRNA-128b expression in gastric cancer group was significantly lower than that in gastric polyp group (q=211.148,P<0.01) and healthy control group (q=249.984,P<0.01),the expression of those in gastric polyp group was also significantly lower compared healthy control group(q=38.232,P<0.01),and the expression was significantly higher after surgery than before surgery (t=15.139,P<0.01).The serum miRNA-128a and miRNA-128b expression had high sensitivity and specificity in the diagnosis of gastric cancer,the sensitivity of combined detection was 78.8%,the specificity was 97.3%,and the area under curve was significantly higher than miRNA-128a (Z=3.436,P<0.01) and miRNA-128b (Z=2.658,P<0.01).The expression of serum miRNA-128a and miRNA-128b in patients with gastric cancer were significantly correlated with tumor cell differentiation,TNM staging,lymph node metastasis and depth of invasion (P<0.01).After 2 years' follow-up,the serum miRNA-128a expression in survival group was significantly lower than that in death group (P<0.01).When its level was >98.47 fmol/L,the sensitivity of predicting death within 2 years was 89.5%,the specificity was 81.8%,and the curve area was 0.889.The serum miRNA-128b expression in survival group was significantly higher than that in death group (P<0.01),when its level was ≤ 94.86 fmol/L,the sensitivity of predicting death within 2 years was 94.7%,the specificity was 81.8%,and the curve area was 0.931. Conclusions Combined detection of serum miRNA-128a and miRNA-128b is helpful for diagnosis in patients with gastric cancer and has important reference value for predicting death in gastric cancer patients within 2 years. [ABSTRACT FROM AUTHOR]

[Objectives] In present work,the characteristics of the sequence structure and expression pattern involving in pathogenesis-related protein gene(BcPR5)in non-heading Chinese cabbage(Brassica campestris ssp. chinensis),were investigated to explore its species-specific function in the tolerance of downy mildew defense.[Methods]The full length sequence of BcPR5 cDNA was cloned from the disease-resisted variety ‘Suzhouqing’ by performing the rapid amplification of cDNA ends(RACE)reactions. The RT-qPCR subsequently was done for investigating the expression pattern of BcPR5 gene under the induction of downy mildew and the treatment of plant hormones involving in MeJ,SA and ABA. Additionally,the prokaryotic expression of BcPR5 protein was performed by SDS-polyacrylamide gel electrophoresis(SDS-PAGE).[Results]The full length of BcPR5 cDNA sequence is 954 bp,of which,732 bp ORF is included which encodes a functional protein by 243 amino acid with the molecular weight of 26.1×103 and isoelectric point of 9.3. The phylogenetic analysis of amino acid homologous suggested that the BcPR5 from the non-heading Chinese cabbage has the highest similarity(100%)with the homologous in Chinese cabbage. The results of RT-qPCR showed that the expression level of BcPR5 gene increased at first and then decreased during infection by downy mildew and abiotic stresses(SA,MeJ and ABA)in the resistance variety ‘Suzhouqing’ and the susceptible variety ‘Aijiaohuang’,and the transcription at higher levels in resistance variety than that of in susceptible variety. Prokaryotic expression results showed that efficient expression of the protein could be realized after induced with 1.0 mmol·L-1 IPTG for 4 h.[Conclusions]These results suggest that BcPR5 plays an important role in response to the tolerance of downy mildew defense in non-heading Chinese cabbage,and will provide a theoretical basis for further functional verification for BcPR5 gene. [ABSTRACT FROM AUTHOR]