Quantitative Real-time Reverse Transcriptase PCR Research Articles

Heat shock in Cronobacter sakazakii induces direct protection and cross-protection against simulated gastric fluid stress

The bacterial heat shock response in foodborne pathogens is caused by exposure to higher temperatures which poses a great threat to food safety because it can undermine food processing interventions and host defense. The study assessed the heat and acid resistance of Cronobacter sakazakii following heat shock (53 °C for 15min). Inactivation curves of the heat-shocked and non-shocked C. sakazakii cells at four temperatures (56, 58, 60, and 62 °C) and simulated gastric fluid (SGF, pH 3.0) were examined and fitted with the log-linear model and the Weibull model. The inactivation parameters obtained on the basis of the Weibull model showed that heat shock significantly (p < 0.05) increased the values of δ (time to reach 1 log reduction) and t3d (time to reach 3 log reduction) under thermal and acid inactivation. The results proved that heat shock provided C. sakazakii direct protection from a more adverse heat challenge and cross-protection from SGF, i.e. there was a heat shock response. Results of sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) revealed that seven protein species showed enhanced expression, while four protein species showed decreased expression in the heat-shocked compared to the non-heat-shocked C. sakazakii cells. Quantitative real-time reverse transcriptase PCR (RT-qPCR) revealed upregulation of six stress related genes, ibpA, ibpB (both encoding molecular chaperons), Hsp15 (encoding heat shock protein), Hsp20 (encoding small heat-shock protein), HspQ (encoding proteases) and rpoS (encoding stationary phase sigma factor), following heat shock treatment. In addition, heat shock induced an increase proportion of saturated fatty acids (SFA), cyclic fatty acids (CFA) and the ratio of saturated fatty acids to unsaturated fatty acids (SFA/USFA), whereas reducing the proportion of unsaturated fatty acids (USFA). Consequently, establishment of inactivation models of C. sakazakii could provide data support for quantitative microbial risk assessment (QMRA). Exploration of enhanced resistance mechanisms might provide clues for prevention and control of contamination by heat-shocked C. sakazakii.

Rapid, early and accurate SARS-CoV-2 detection using RT-qPCR in primary care: a prospective cohort study (REAP-1)

ObjectivesWe explore the importance of SARS-CoV-2 sentinel surveillance testing in primary care during a regional COVID-19 outbreak in Austria.DesignProspective cohort study.SettingA single sentinel practice serving 22 829 people in the...

MiR-22-3p Suppresses Cell Migration and Invasion by Targeting PLAGL2 in Breast Cancer.

To investigate the expression of miR-22-3p in breast cancer and the mechanism of targeting PLAGL2 to inhibit the invasion and migration in human breast cancer. An experimental study. Department of Oncology and Department of General Surgery, The People's Hospital of China Three Gorges University, China, from March 2019 to December 2020. The miR-22-3p expression level in 41 paired human primary breast invasive ductal carcinoma tissues and para-cancer tissues was obtained by real-time fluorescence quantitative reverse transcriptase PCR (qRT-PCR). The effect of miR-22-3p on the proliferation of breast cancer cells was detected by growth curve method. Online software TargetScan was used to predict the target genes of miR-22-3p. The prediction results were verified by luciferase reporter gene assay and qRT⁃PCR. MiR-22-3p expression was significantly decreased in the breast cancer tissues than in para⁃carcinoma normal breast tissues (p<0.05). Over-expression of miR-22-3p can inhibit the proliferation of MCF-7 cells significantly. Pleomorphic adenoma gene-like protein 2(PLAGL2)is the predicted target gene of miR-22-3p. MiR-22-3p binds to its predicted target gene PLAGL2-3'UTR. The expression of miR-22-3p was negatively correlated with PLAGL2 in MCF-7 cells. MiR-22-3p could suppress the proliferation of breast cancer by targeting PLAGL2. This suggests that miR-22-3p may be a strategy of choice for targeted therapy of breast cancer. Key Words: Breast cancer, MiR-22-3p, PLAGL2, Cell proliferation.

Human equilibrative nucleoside transporter-1 gene expression in acute myeloid leukemia patients treated with cytarabine

Objectives This study aimed to demonstrate human equilibrative nucleoside transporter-1 (HENT1) gene expression patterns in acute myeloid leukemia (AML) patients and its role in disease progression. Background Cytarabine is the primary drug in different treatment schemas for AML and requires the HENT1 to enter cells. Patients and methods In this study, we analyzed HENT1 expression levels in 40 AML patients and 20 controls using the real-time quantitative reverse-transcriptase PCR. Results HENT1 was expressed in 42.5% of AML cases and 36% of controls. Our results showed a correlation between the HENT1 gene expression and the overall survival (OS), where HENT1-positive patients had a higher survival rate than HENT1-negative patients (P = 0.04). The results also showed a correlation between gene appearance and the response rate of treatment, as patients with positive HENT1 gene expression had a higher rate of complete recovery (58.8%) than the patients with negative HENT1 gene expression (30.4%). HENT1 expression was significantly correlated with OS and complete remission. Conclusion HENT1 gene expression is associated with better response to cytarabine treatment, with better OS in AML patients, both children and adults. HENT1 signaling may represent a novel therapeutic approach for the treatment of AML.

Efficient Secretion and Recombinant Production of a Lactobacillal α-amylase in Lactiplantibacillus plantarum WCFS1: Analysis and Comparison of the Secretion Using Different Signal Peptides.

Lactic acid bacteria (LAB) have been used as starter cultures and producers of enzymes, antimicrobial peptides or metabolites that contribute to the flavor, texture and safety of food products. Lactiplantibacillus plantarum, one of the best-studied LAB, is considered as safe and effective cell factory for food applications. In this study, our aim was to use L. plantarum as the producer for high levels of a food-grade lactobacillal α-amylase, which has potential applications in food, fermentation and feed industries. The native form of an α-amylase (AmyL) from L. plantarum S21, an amylolytic LAB isolated from Thai fermented rice noodles, was expressed in L. plantarum WCFS1 using the pSIP expression system. The secretion of the α-amylase was driven by the native signal peptides of the α-amylases from L. plantarum S21 (SP_AmyL) and Lactobacillus amylovorus NRRL B-4549 (SP_AmyA), as well as by three Sec-type signal peptides derived from L. plantarum WCFS1; Lp_2145, Lp_3050, and Lp_0373. Among the tested signal peptides, Lp_2145 appears to be the best signal peptide giving the highest total and extracellular enzymatic activities of α-amylase AmyL from L. plantarum S21, which were 13.1 and 8.1 kU/L of fermentation, respectively. These yields were significantly higher than the expression and secretion in L. plantarum WCFS1 using the native signal peptide SP_AmyL, resulting in 6.2- and 5.4-fold increase in total and extracellular activities of AmyL, respectively. In terms of secretion efficiency, Lp_0373 was observed as the most efficient signal peptide among non-cognate signal peptides for the secretion of AmyL. Real-time reverse-transcriptase quantitative PCR (RT-qPCR) was used to estimate the mRNA levels of α-amylase transcript in each recombinant strain. Relative quantification by RT-qPCR indicated that the strain with the Lp_2145 signal peptide-containing construct had the highest mRNA levels and that the exchange of the signal peptide led to a change in the transcript level of the target gene.

Diagnostic performance of rapid antigen test for COVID-19 and the effect of viral load, sampling time, subject’s clinical and laboratory parameters on test accuracy

BackgroundEgypt was among the first 10 countries in Africa that experienced COVID-19 cases. The sudden surge in the number of cases is overwhelming the capacity of the national healthcare system, particularly in developing countries. Central to the containment of the ongoing pandemic is the availability of rapid and accurate diagnostic tests that could pinpoint patients at early disease stages. In the current study, we aimed to (1) Evaluate the diagnostic performance of the rapid antigen test (RAT) “Standard™ Q COVID-19 Ag” against reverse transcriptase quantitative real-time PCR (RT-qPCR) in eighty-three swabs collected from COVID-19 suspected individuals showing various demographic features, clinical and radiological findings. (2) Test whether measuring laboratory parameters in participant’s blood would enhance the predictive accuracy of RAT. (3) Identify the most important features that determine the results of both RAT and RT-qPCR. MethodsDiagnostic measurements (e.g. sensitivity, specificity, etc.) and receiver operating characteristic curve were used to assess the clinical performance of “Standard™ Q COVID-19 Ag”. We used the support vector machine (SVM) model to investigate whether measuring laboratory indices would enhance the accuracy of RAT. Moreover, a random forest classification model was used to determine the most important determinants of the results of RAT and RT-qPCR for COVID-19 diagnosis. ResultsThe sensitivity, specificity, and accuracy of RAT were 78.2, 64.2, and 75.9%, respectively. Samples with high viral load and those that were collected within one-week post-symptoms showed the highest sensitivity and accuracy. The SVM modeling showed that measuring laboratory indices did not enhance the predictive accuracy of RAT. Conclusion“Standard™ Q COVID-19 Ag” should not be used alone for COVID-19 diagnosis due to its low diagnostic performance relative to the RT-qPCR. RAT is best used at the early disease stage and in patients with high viral load.

Development and validation of a new triplex real-time quantitative reverse Transcriptase-PCR assay for the clinical detection of SARS-CoV-2

To increase the repertoire of PCR based laboratory developed tests (LDTs) for the detection of SARS-CoV-2, we describe a new multiplex assay (SORP), targeting the SARS-CoV-2's, Spike and ORF8 genes. The widely used human RNaseP internal control was modified to specifically co-amplify the RNaseP mRNA. The SORP triplex assay was tested on a cohort (n = 372; POS = 144/NEG = 228) of nasopharyngeal flocked swab (NPFS) specimens, previously tested for the presence of SARS-CoV-2 using a PCR assay targeting E and RdRp genes. The overall sensitivity and specificity of the SORP assay was: 99.31% (95% CI: 96.22–99.98%), 100.0% (95% CI: 98.4–100%) respectively. The SORP assay could also detect a panel of variants of concern (VOC) from the B1.1.7 (UK) and B1.351 (SA) lineage. In summary, access to a repertoire of new SARS-CoV-2 LDT's would assist diagnostic laboratories in developing strategies to overcome some of the testing issues encountered during high-throughput SARS-CoV-2 testing.

Novel Long Non-coding RNA and LASSO Prediction Model to Better Identify Pulmonary Tuberculosis: A Case-Control Study in China.

IntroductionThe insufficient understanding and misdiagnosis of clinically diagnosed pulmonary tuberculosis (PTB) without an aetiological evidence is a major problem in the diagnosis of tuberculosis (TB). This study aims to confirm the value of Long non-coding RNA (lncRNA) n344917 in the diagnosis of PTB and construct a rapid, accurate, and universal prediction model.MethodsA total of 536 patients were prospectively and consecutively recruited, including clinically diagnosed PTB, PTB with an aetiological evidence and non-TB disease controls, who were admitted to West China hospital from Dec 2014 to Dec 2017. The expression levels of lncRNA n344917 of all patients were analyzed using reverse transcriptase quantitative real-time PCR. Then, the laboratory findings, electronic health record (EHR) information and expression levels of n344917 were used to construct a prediction model through the Least Absolute Shrinkage and Selection Operator algorithm and multivariate logistic regression.ResultsThe factors of n344917, age, CT calcification, cough, TBIGRA, low-grade fever and weight loss were included in the prediction model. It had good discrimination (area under the curve = 0.88, cutoff = 0.657, sensitivity = 88.98%, specificity = 86.43%, positive predictive value = 85.61%, and negative predictive value = 89.63%), consistency and clinical availability. It also showed a good replicability in the validation cohort. Finally, it was encapsulated as an open-source and free web-based application for clinical use and is available online at https://ziruinptb.shinyapps.io/shiny/.ConclusionCombining the novel potential molecular biomarker n344917, laboratory and EHR variables, this web-based prediction model could serve as a user-friendly, accurate platform to improve the clinical diagnosis of PTB.

Hepatocyte steatosis inhibits hepatitis B virus secretion via induction of endoplasmic reticulum stress.

The effects of hepatocyte steatosis on hepatitis B virus (HBV) DNA replication and HBV-related antigen secretion are incompletely understood. The aims of this study are to explore the effects and mechanism of hepatocyte steatosis on HBV replication and secretion. Stearic acid (SA) and oleic acid (OA) were used to induce HepG2.2.15 cell steatosis in this study. The expressions of glucose-regulated protein 78 (GRP78), phosphorylation of protein kinase R-like endoplasmic reticulum (ER) kinase (p-PERK), and eukaryotic translation initiation factor 2α (p-eIF2α) were detected by Western blotting (WB). HBV DNA, HBsAg, and HBeAg in the supernatant were determined by real-time fluorescent polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay. Intracellular HBV DNA, HBsAg level, and HBV RNA were measured by real-time fluorescent PCR, WB, and real-time quantitative reverse transcriptase-PCR, respectively. The results showed that SA and OA significantly increased intracellular lipid droplets and triglyceride levels. SA and OA significantly induced GRP78, p-PERK, and p-eIF2α expressions from 24 to 72 h. 4-phenylbutyric acid (PBA) alleviated ER stress induced by SA. SA promoted intracellular HBsAg and HBV DNA accumulation; however, it inhibited the transcript of HBV 3.5 kb mRNA and S mRNA. The secretion of HBsAg and HBV DNA inhibited by SA or OA could be partially restored by pretreatment with PBA but not by inhibiting GRP78 expression with siRNA. Hepatocyte steatosis inhibits HBsAg and HBV DNA secretion via induction of ER stress in hepatocytes, but not via induction of GRP78.

Temperature affects the tolerance of Liriomyza trifolii to insecticide abamectin

The leafminer fly, Liriomyza trifolii, is an invasive pest of horticultural and vegetable crops that possesses a robust competitive ability when compared to congeneric species, especially with respect to temperature and insecticide tolerance. Abamectin, which is commonly used to control L. trifolii in the field, was selected as the target insecticide in this study. Our objective was to study the effect of abamectin and high temperature stress on L. trifolii mortality and the expression of genes encoding cytochrome P450 (CYP450s) and heat shock proteins (Hsps) by quantitative real-time reverse transcriptase PCR (qRT-PCR). When L. trifolii was exposed to abamectin followed by exposure to 40 °C (LC50 +HT40), mortality showed a significant increase, whereas exposure to 40 ℃ followed by abamectin (HT40+LC50) reduced mortality relative to abamectin or HT40 alone. Expression of three CYP450s in the CYP4 family was highest in the HT40+LC50 treatment, followed by the LC50+HT40 treatment. The expression levels of CYP18A1 (CYP18 family) were not significantly different among treatments, and CYP301A1 (CYP301 family) was only sensitive to temperature (HT40). The expression of five sHsps showed similar expression patterns and were highly responsive to the LC50+HT40 treatment, followed by the HT40 and HT40+LC50 treatments. Based on CYP450s and Hsps expression levels, our findings that suggest that L. trifolii exhibits adaptive cross-tolerance to high temperature and abamectin. This study provides a framework for selecting the most effective application time for abamectin with respect to controlling L. trifolii, which will ultimately reduce the overuse of pesticides.

Identification of potential genes in upper tract urothelial carcinoma using next-generation sequencing with bioinformatics and in vitro analyses.

BackgroundWe aimed to identify prognostic biomarkers of upper tract urothelial carcinomas (UTUCs), including microRNAs (miRNAs) and genes which account for only 5% to 10% of all urothelial carcinomas (UCs). In Taiwan, this figure is markedly higher, where it can reach up to 30% of UC cases.Materials and MethodsUsing next-generation sequencing (NGS), we analyzed two pairs of renal pelvis tumors and adjacent normal urothelial tissues to screen miRNAs and messenger RNAs. By combining bioinformatics analysis from miRmap, Gene Expression Omnibus (GEO), and Oncomine and Ingenuity® Pathway Analysis databases, we identified candidate genes. To search for upstream miRNAs with exact target binding sites, we used miRmap, TargetScan, and miRDB to enforce evidence. Then, we clarified gene and protein expression through an in vitro study using western blot analysis and quantitative real-time reverse transcriptase-PCR.ResultsInteractions between selected target genes obtained using the NGS and miRmap methods were assessed through a Venn diagram analysis. Six potential genes, namely, PDE5A, RECK, ZEB2, NCALD, PLCXD3 and CYBRD1 showed significant differences. Further analysis of gene expression from the GEO dataset indicated lower expression of PDE5A, RECK, ZEB2, and CYBRD1 in bladder cancer tissue than in normal bladder mucosa, which indicated that PDE5A, RECK, ZEB2, and CYBRD1 may act as tumor suppressors in UTUC. In addition, we compared the expression of these genes in various UC cell lines (RT4, BFTC905, J82, T24, UMUC3, 5637, BFTC 909, UMUC14) and found decreased expression of PDE5A in muscle-invasive UC cells compared with the RT4 cell line. Furthermore, by using paired UTUC and normal tissues from 20 patients, lower PDE5A expression was also demonstrated in tumor specimens.ConclusionsOur findings suggest these candidate genes may play some roles in UTUC progression. We propose that these markers may be potential targets clarified by in vitro and in vivo experiments. PDE5A also potentially presents tumor suppressor genes, as identified by comparing the expression between normal and tumor specimens.

PiRNA-823 Is a Unique Potential Diagnostic Non-Invasive Biomarker in Colorectal Cancer Patients.

Early detection of colorectal cancer (CRC) is the most important factor in deciding its prognosis, so the need to develop an accurate screening test is a must. P-element induced wimpy testis (PIWI) RNA-823 (piR-823) is one of the first piRNAs recognized to be linked to malignancy. We aimed to investigate the expression levels of piR-823 in both serum and tissues of colorectal cancer patients and the ability to use its serum level as a non-invasive diagnostic biomarker to detect colorectal cancer. We determined piR-823 expression levels in 84 serum samples of CRC patients, 75 serum samples of healthy controls, and biological specimens obtained from the 84 patients with colorectal cancer from both the tumor tissues and the normal neighboring tissues using quantitative real-time reverse transcriptase-PCR. We showed that piR-823 had significantly higher serum and tissue expression levels in CRC patients compared to the controls. We observed a significant positive correlation between piR-823 serum levels and the staging of CRC, with significantly higher levels exhibiting advanced stages of CRC (III and IV). This translates into poorer differentiation and lymph node metastasis. The receiver operating characteristic curve (ROC curve) test showed 83.3% sensitivity and 89.3% specificity at a cut-off value of >5.98-fold change, with an area under the curve of 0.933 (p < 0.0001) concerning the ability of piR-823 in diagnosing patients with colorectal carcinoma. piR-823 expression is upregulated in colorectal cancer patients’ serum and tissues, and it can be used as a diagnostic noninvasive biomarker for CRC.

Circular RNA hsa_circ_0003288 induces EMT and invasion by regulating hsa_circ_0003288/miR-145/PD-L1 axis in hepatocellular carcinoma

BackgroundEpithelial-mesenchymal transition (EMT) has been associated with wound healing, tumorigenesis, and metastasis. Circular RNAs (circRNAs) are functional non-coding RNAs involved in multiple human cancers. However, whether and how circRNAs contribute to the EMT in hepatocellular carcinomas (HCC) remains to be deciphered. In this study, we investigated the regulation and function of hsa_circ_0003288 on programmed death-1 ligand 1 (PD-L1) during EMT and HCC invasiveness.MethodsHsa_circ_0003288 expression was measured by real-time quantitative reverse transcriptase PCR (qRT-PCR). Luciferase reporter assays, RNA pull-down assay and fluorescence in situ hybridization (FISH) were used to determine the correlation between hsa_circ_0003288 and miR-145 and between miR-145 and PD-L1. Furthermore, ectopic overexpression and siRNA-mediated downregulation of hsa_circ_0003288, transwell assays, and in vivo studies were used to determine the function of hsa_circ_0003288 on the EMT and invasiveness of L02 and HCC cells.ResultsmiR-145 directly targeted the PD-L1 3′-untranslated region (UTR) region, and hsa_circ_0003288 acted as a miR-145 sponge to regulate PD-L1 expression. Overexpression of hsa_circ_0003288 increased PD-L1 levels and promoted EMT, migration, and invasiveness of L02 cells. These observations were reversed after knockdown of hsa_circ_0003288 in HepG2 and Huh7 cells. Overexpression of PD-L1 rescued EMT, migration, and invasiveness of HepG2 and Huh7 cells after knockdown of hsa_circ_0003288. Furthermore, hsa_circ_0003288 knockdown reduced EMT in in vivo studies. Hsa_circ_0003288/PD-L1 axis was found to mediate the metastatic phenotypes via the PI3K/Akt pathway in HCC. Additionally, expression levels of hsa_circ_0003288 were increased and positively correlated with PD-L1 expression in HCC tissues.ConclusionOur findings demonstrated that hsa_circ_0003288 promoted EMT and invasion of HCC via the hsa_circ_0003288/miR-145/PD-L1 axis through the PI3K/Akt pathway. Targeting hsa_circ_0003288 may be a therapeutic strategy for the treatment of HCC.

Expression of type II toxin-antitoxin systems and ClpP protease of methicillin-resistant Staphylococcus aureus under thermal and oxidative stress conditions.

Background and Objectives:Staphylococcus aureus is a main human pathogen that causes a variety of chronic to persistent infections. Across the diverse factors of pathogenesis in bacteria, Toxin-Antitoxin (TA) systems can be considered as an anti-bacterial target due to their involvement in cellular physiology counting stress responses. Here, the expression of TA system genes and ClpP protease was investigated under the thermal and oxidative conditions in S. aureus strains.Materials and Methods:The colony-forming unit (CFU) was used to determine the effects of thermal and oxidative stresses on bacterial survival. Moreover, the expressions of TA system genes in S. aureus strains were evaluated 30 min and 1 h after thermal and oxidative stresses, respectively, by quantitative reverse transcriptase real-time PCR (qRT-PCR).Results:The cell viability was constant across thermal stress while oxidative stress induction showed a significantly decrease in the growth of Methicillin-Resistant S. aureus (MRSA) strain. Based on the qRT-PCR results, the expression of mazF gene increased under both thermal and oxidative stresses in the MRSA strain.Conclusion:A putative TA system (namely immA/irrA) most likely has a role under the stress condition of S. aureus. The MRSA strain responds to stress by shifting the expression level of TA genes that has diverse effects on the survival of the pathogen due to the stress conditions. The TA systems may be introduced as potential targets for antibacterial treatment.

Norovirus Extraction from Frozen Raspberries Using Magnetic Silica Beads

Human noroviruses (HuNoV) are among the main causes of acute gastroenteritis worldwide. Frozen raspberries have been linked to several HuNoV food-related outbreaks. However, the extraction of HuNoV RNA from frozen raspberries remains challenging. Recovery yields are low, and real-time quantitative reverse transcriptase PCR (RT-qPCR) inhibitors limit the sensitivity of the detection methodologies. A new approach using fine magnetic silica beads was developed for the extraction of HuNoV spiked on frozen raspberries. Relatively low recovery yields were observed with both the magnetic silica bead and the reference ISO 15216-1:2017 methods. High RT-qPCR inhibition was observed with the ISO 15216-1:2017 recommended amplification kit but could be reduced by using an alternative kit. Reducing RT-qPCR inhibition is important to limit the number of inconclusive HuNoV assays thus increasing the capacity to assess the HuNoV prevalence in frozen raspberries.

High performance of a novel antigen detection test on nasopharyngeal specimens for diagnosing SARS-CoV-2 infection.

The severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) pandemic has become a major public health issue worldwide. Developing and evaluating rapid and easy‐to‐perform diagnostic tests is a high priority. The current study was designed to assess the diagnostic performance of an antigen‐based rapid detection test (COVID‐VIRO®) in a real‐life setting. Two nasopharyngeal specimens of symptomatic or asymptomatic adult patients hospitalized in the Infectious Diseases Department or voluntarily accessing the COVID‐19 Screening Department of the Regional Hospital of Orléans, France, were concurrently collected. The diagnostic specificity and sensitivity of COVID VIRO® results were compared to those of real‐time reverse‐transcriptase quantitative polymerase chain reaction (RT‐qPCR) results. A subset of patients underwent an additional oropharyngeal and/or saliva swab for rapid testing. A total of 121 patients confirmed to be infected and 127 patients having no evidence of recent or ongoing infection were enrolled for a total of 248 nasopharyngeal swab specimens. Overall, the COVID‐VIRO® sensitivity was 96.7% (CI, 93.5%–99.9%). In asymptomatic patients, symptomatic patients having symptoms for more than 4 days and those with an RT‐qPCR cycle threshold value ≥ 32, the sensitivities were 100%, 95.8%, and 91.9%, respectively. The concordance between RT‐qPCR and COVID VIRO® rapid test results was 100% for the 127 patients with no SARS‐CoV‐2 infection. The COVID‐VIRO® test had 100% specificity and sensitivity greater than 95%, which are better than the recommendations set forth by the WHO (specificity ≥ 97%–100%, sensitivity ≥ 80%). These rapid tests may be particularly useful for large‐scale screening in emergency departments, low‐resource settings, and airports.

NTPDase8 protects mice from intestinal inflammation by limiting P2Y6 receptor activation: identification of a new pathway of inflammation for the potential treatment of IBD

ObjectiveNucleotides are danger signals that activate inflammatory responses via binding P2 receptors. The nucleoside triphosphate diphosphohydrolase-8 (NTPDase8) is an ectonucleotidase that hydrolyses P2 receptor ligands. We investigated the role of...

The expression of microRNA-199 - a new potential biomarker for immunomediated inflammation

The etiology and pathogenesis of inflammatory bowel disease (IBD) remain undetermined but an interaction between environmental, genetic and immunological factors is most widely accepted. Recent studies examine the expression of miRNAs in peripheral blood and tissues in IBD patients. Our study aims to assess and correlate the serum expression of miR-199 in IBD patients with clinical parameters such as extent, activity, and severity of the disease. A total of 35 patients with ulcerative colitis (UC) and 35 patients with Crohn’s disease (CD) were included in the study. Serum miR-199 expression in both IBD diseases was assessed using reverse transcriptase quantitative real-time PCR (RT-qPCR). Circulating miR-199 levels were also correlated with disease extent, activity, and severity indices (CDAI, Montreal classification, Partial Mayo score). Serum expression of miR-199 in the 70 patients was also compared miR-199 serum levels in 30 healthy control subjects. The patients’ group showed mean serum miR-199 expression of 2.39 for CD, 1.08 for UC, and 1.26 for the control group with significant difference in the expression between groups. From the current study, we could conclude that there is a significant correlation between increased serum expression of miR-199 and disease activity (UC), extent (CD), and severity (CD and UC).

Inhibitory effect of anti-malarial agents on the expression of proinflammatory chemokines via Toll-like receptor 3 signaling in human glomerular endothelial cells

Objective Although anti-malarial agents, chloroquine (CQ) and hydroxychloroquine (HCQ) are currently used for the treatment of systemic lupus erythematosus, their efficacy for lupus nephritis (LN) remains unclear. Given that upregulation of glomerular Toll-like receptor 3 (TLR3) signaling plays a pivotal role in the pathogenesis of LN, we examined whether CQ and HCQ affect the expression of the TLR3 signaling-induced representative proinflammatory chemokines, monocyte chemoattractant protein-1 (MCP-1), and C–C motif chemokine ligand 5 (CCL5) in cultured human glomerular endothelial cells (GECs). Methods We examined the effect of polyinosinic-polycytidylic acid (poly IC), an agonist of TLR3, on MCP-1, CCL5 and interferon (IFN)-β expression in GECs. We then analyzed whether pretreatment with CQ, HCQ, or dexamethasone (DEX) inhibits poly IC-induced expression of these chemokines using real-time quantitative reverse transcriptase PCR and ELISA. Phosphorylation of signal transducers and activator of transcription protein 1 (STAT1) was examined using western blotting. Results Poly IC increased MCP-1 and CCL5 expression in a time- and concentration-dependent manner in GECs. Pretreating cells with CQ, but not DEX, attenuated poly IC-induced MCP-1 and CCL5 expression; however, HCQ pretreatment attenuated poly IC-induced CCL5, but not MCP-1. HCQ did not affect the expression of IFN-β and phosphorylation of STAT-1. Conclusion Considering that TLR3 signaling is implicated, at least in part, in LN pathogenesis, our results suggest that anti-malarial agents exert a protective effect against the development of inflammation in GECs, as postulated in LN. Interestingly, CQ is a rather powerful inhibitor compared with HCQ on TLR3 signaling-induced chemokine expression in GECs. In turn, these findings may further support the theory that the use of HCQ is safer than CQ in a clinical setting. However, further detailed studies are needed to confirm our preliminary findings.

Disinfectant Effectiveness Against SARS-CoV-2 and Surrogates Using Cell Culture and RT-PCR

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes the global COVID-19 pandemic. Limited studies have been performed on various types of disinfectants utilized to control the spread of this highly contagious virus. This study aimed to investigate the inactivation of SARS-CoV-2 surrogate virus, hCoV-229E using an <i>in vitro</i> to test the anti-infectivity activity of the humidifier buffers (A and B, Lumichem<SUP>TM</SUP>). A real-time reverse transcriptase quantitative PCR (RT-qPCR) assay was used to evaluate the effectiveness of these disinfectants on the degradation of viral RNA in a time dependent manner. The effects of disinfectants on viral infectivity were determined using a tissue culture infectious dose (TCID50) assay of a surrogate virus, hCoV-229E, in MRC-5 cell culture. The results demonstrated that the Lumichem<SUP>TM</SUP> buffers A and B had a 2 to 3-log₁₀ reduction inactivation using cell culture after a short exposure compared to the control, indicating the disinfection efficacy of the tested anti-infectivity compounds. The Lumichem<SUP>TM</SUP> buffers A and B in addition did not affect the viral genomic RNA of a surrogate virus, hCoV-229E, thus representing an additional benefit with a negligible impact to operators and those in close contact when providing in-situ operational cleaning.