scholarly journals SARS-CoV-2 receptor ACE2 is expressed in human conjunctival tissue, especially in diseased conjunctival tissue

2020 ◽  
Author(s):  
Shengjie Li ◽  
Danhui Li ◽  
Jianchen Fang ◽  
Qiang Liu ◽  
Wenjun Cao ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Quantitative Polymerase Chain Reaction ◽  
Normal Subjects ◽  
Chain Reaction ◽  
Western Blot Assay ◽  
Conjunctival Cells ◽  
Polymerase Chain ◽  
Entry Receptor ◽  
Conjunctival Cyst ◽  
Conjunctival Epithelial Cells

COVID-19 virus has currently caused major outbreaks worldwide. ACE2 is a major cellular-entry receptor for the COVID-19 virus. Although ACE2 is known to be expressed in many organs, whether it is expressed by the conjunctival tissue is largely unknown. Human conjunctival tissues from 68 subjects were obtained, which included 10 subjects with conjunctival nevi, 20 subjects with conjunctivitis, 9 subjects with conjunctival papilloma, 16 subjects with conjunctival cyst, 7 subjects with conjunctival polyps, and 6 ocular traumas as normal subjects. Expression of ACE2 was evaluated by immunohistochemistry, immunofluorescence, reverse transcriptase-quantitative polymerase chain reaction, and western blot assay. We observed the expression of ACE2 by conjunctival tissues, expecially in conjunctival epithelial cells. ACE2 was significantly (p<0.001) overexpressed in conjunctival cells obtained from subjects with conjunctivitis, conjunctival nevi, conjunctival papilloma, conjunctival cyst, and conjunctival polyps epithelial cells when compared to that in conjunctival epithelial cells obtained from control subjects. Collectively, clinical features of reported COVID-19 patients combined with our results indicate that COVID-19 is likely to be transmitted through the conjunctiva.

scholarly journals Use of Fluorescence Quantitative Polymerase Chain Reaction (PCR) for the Detection of Escherichia coli Adhesion to Pig Intestinal Epithelial Cells

2016 ◽  
Vol 19 (3) ◽  
pp. 619-625 ◽  
Author(s):  
C.H. Dai ◽  
L.N. Gan ◽  
W.U. Qin ◽  
C. Zi ◽  
G.Q. Zhu ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Polymerase Chain Reaction ◽  
Epithelial Cells ◽  
Intestinal Epithelial Cells ◽  
Quantitative Polymerase Chain Reaction ◽  
Relative Number ◽  
Intestinal Epithelial ◽  
Chain Reaction ◽  
E Coli ◽  
Polymerase Chain

AbstractAn efficient and accurate method to testEscherichia coli(E. coli) adhesion to intestinal epithelial cells will contribute to the study of bacterial pathogenesis and the function of genes that encode receptors related to adhesion. This study used the quantitative real-time polymerase chain reaction (qPCR) method. qPCR primers were designed from thePILINgene ofE. coliF18ab, F18ac, and K88ac, and the pig β-ACTINgene. Total deoxyribonucleic acid (DNA) fromE. coliand intestinal epithelial cells (IPEC-J2 cells) were used as templates for qPCR. The 2−ΔΔCtformula was used to calculate the relative number of bacteria in cultures of different areas. We found that the relative numbers of F18ab, F18ac, and K88ac that adhered to IPEC-J2 cells did not differ significantly in 6-, 12-, and 24-well culture plates. This finding indicated that there was no relationship between the relative adhesion number ofE. coliand the area of cells, so the method of qPCR could accurately test the relative number ofE. coli. This study provided a convenient and reliable testing method for experiments involvingE. coliadhesion, and also provided innovative ideas for similar detection methods.

scholarly journals Plant-Derived Antimicrobials ReduceE. coliO157:H7 Virulence Factors Critical for Colonization in Cattle Gastrointestinal TractIn Vitro

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Sangeetha Ananda Baskaran ◽  
Kumar Venkitanarayanan
Keyword(s):  
Polymerase Chain Reaction ◽  
Epithelial Cells ◽  
Rumen Fluid ◽  
Quantitative Polymerase Chain Reaction ◽  
Chain Reaction ◽  
E Coli ◽  
Intestinal Contents ◽  
Polymerase Chain

This study investigated the effect of subinhibitory concentrations (SIC) of five plant-derived antimicrobials (PDAs), namely, trans cinnamaldehyde, eugenol, carvacrol, thymol, andβ-resorcylic acid, onE. coliO157:H7 (EHEC) attachment and invasion of cultured bovine colonic (CO) and rectoanal junction (RAJ) epithelial cells. In addition, PDAs’ effect on EHEC genes critical for colonization of cattle gastrointestinal tract (CGIT) was determined in bovine rumen fluid (RF) and intestinal contents (BICs). Primary bovine CO and RAJ epithelial cells were established and were separately inoculated with three EHEC strains with or without (control) SIC of each PDA. Following incubation, EHEC that attached and invaded the cells were determined. Furthermore, the expression of EHEC genes critical for colonization in cattle was investigated using real-time, quantitative polymerase chain reaction in RF and BICs. All the PDAs decreased EHEC invasion of CO and RAJ epithelial cells (P<0.05). The PDAs also downregulated (P<0.05) the expression of EHEC genes critical for colonization in CGIT. Results suggest that the PDAs could potentially be used to control EHEC colonization in cattle; however follow-upin vivostudies in cattle are warranted.

AN IMPROVED METHOD FOR INHIBITOR FREE NUCLEIC ACIDS FROM POLYPHENOL RICH LEAVES OF MUSA SPP

2017 ◽  
Vol 23 (1) ◽  
Author(s):  
N.NANDHA KUMAR ◽  
K. SOURIANATHA SUNDARAM ◽  
D. SUDHAKAR ◽  
K.K. KUMAR
Keyword(s):  
Polymerase Chain Reaction ◽  
Quantitative Polymerase Chain Reaction ◽  
Proteinase K ◽  
Chain Reaction ◽  
Banana Plant ◽  
High Molecular Weight Dna ◽  
Musa Spp ◽  
Leaf Tissues ◽  
Polymerase Chain

Excessive presence of polysaccharides, polyphenol and secondary metabolites in banana plant affects the quality of DNA and it leads to difficult in isolating good quality of DNA. An optimized modified CTAB protocol for the isolation of high quality and quantity of DNA obtained from banana leaf tissues has been developed. In this protocol a slight increased salt (NaCl) concentration (2.0M) was used in the extraction buffer. Polyvinylpyrrolidone (PVP) and Octanol were used for the removal of polyphenols and polymerase chain reaction (PCR) inhibitors. Proteins like various enzymes were degraded by Proteinase K and removed by centrifugation from plant extract during the isolation process resulting in pure genomic DNA, ready to use in downstream applications including PCR, quantitative polymerase chain reaction (qPCR), ligation, restriction and sequencing. This protocol yielded a high molecular weight DNA isolated from polyphenols rich leaves of Musa spp which was free from contamination and colour. The average yields of total DNA from leaf ranged from 917.4 to 1860.9 ng/ìL. This modified CTAB protocol reported here is less time consuming 4-5h, reproducible and can be used for a broad spectrum of plant species which have polyphenol and polysaccharide compounds.

scholarly journals Analysis and validation of a highly sensitive one-step nested quantitative real-time polymerase chain reaction assay for specific detection of severe acute respiratory syndrome coronavirus 2

2020 ◽  
Vol 17 (1) ◽  
Author(s):  
Yang Zhang ◽  
Chunyang Dai ◽  
Huiyan Wang ◽  
Yong Gao ◽  
Tuantuan Li ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Real Time ◽  
Quantitative Polymerase Chain Reaction ◽  
Clinical Samples ◽  
Chain Reaction ◽  
Pcr Assay ◽  
Qrt Pcr ◽  
Highly Sensitive ◽  
One Step ◽  
Polymerase Chain

Abstract Background Coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2, is posing a serious threat to global public health. Reverse transcriptase real-time quantitative polymerase chain reaction (qRT-PCR) is widely used as the gold standard for clinical detection of SARS-CoV-2. Due to technical limitations, the reported positive rates of qRT-PCR assay of throat swab samples vary from 30 to 60%. Therefore, the evaluation of alternative strategies to overcome the limitations of qRT-PCR is required. A previous study reported that one-step nested (OSN)-qRT-PCR revealed better suitability for detecting SARS-CoV-2. However, information on the analytical performance of OSN-qRT-PCR is insufficient. Method In this study, we aimed to analyze OSN-qRT-PCR by comparing it with droplet digital PCR (ddPCR) and qRT-PCR by using a dilution series of SARS-CoV-2 pseudoviral RNA and a quality assessment panel. The clinical performance of OSN-qRT-PCR was also validated and compared with ddPCR and qRT-PCR using specimens from COVID-19 patients. Result The limit of detection (copies/ml) of qRT-PCR, ddPCR, and OSN-qRT-PCR were 520.1 (95% CI: 363.23–1145.69) for ORF1ab and 528.1 (95% CI: 347.7–1248.7) for N, 401.8 (95% CI: 284.8–938.3) for ORF1ab and 336.8 (95% CI: 244.6–792.5) for N, and 194.74 (95% CI: 139.7–430.9) for ORF1ab and 189.1 (95% CI: 130.9–433.9) for N, respectively. Of the 34 clinical samples from COVID-19 patients, the positive rates of OSN-qRT-PCR, ddPCR, and qRT-PCR were 82.35% (28/34), 67.65% (23/34), and 58.82% (20/34), respectively. Conclusion In conclusion, the highly sensitive and specific OSN-qRT-PCR assay is superior to ddPCR and qRT-PCR assays, showing great potential as a technique for detection of SARS-CoV-2 in patients with low viral loads.

scholarly journals Modulation of the Tissue Expression Pattern of Zebrafish CRP-Like Molecules Suggests a Relevant Antiviral Role in Fish Skin

Biology ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 78
Author(s):  
Melissa Bello-Perez ◽  
Mikolaj Adamek ◽  
Julio Coll ◽  
Antonio Figueras ◽  
Beatriz Novoa ◽  
...  
Keyword(s):  
Gene Expression ◽  
Bacterial Infections ◽  
Quantitative Polymerase Chain Reaction ◽  
Tissue Expression ◽  
Interferon Response ◽  
Fish Skin ◽  
Tissue Expression Pattern ◽  
Chain Reaction ◽  
Polymerase Chain ◽  
Antiviral Role

Recent studies suggest that short pentraxins in fish might serve as biomarkers for not only bacterial infections, as in higher vertebrates including humans, but also for viral ones. These fish orthologs of mammalian short pentraxins are currently attracting interest because of their newly discovered antiviral activity. In the present work, the modulation of the gene expression of all zebrafish short pentraxins (CRP-like proteins, CRP1-7) was extensively analyzed by quantitative polymerase chain reaction. Initially, the tissue distribution of crp1-7 transcripts and how the transcripts varied in response to a bath infection with the spring viremia of carp virus, were determined. The expression of crp1-7 was widely distributed and generally increased after infection (mostly at 5 days post infection), except for crp1 (downregulated). Interestingly, several crp transcription levels significantly increased in skin. Further assays in mutant zebrafish of recombinant activation gene 1 (rag1) showed that all crps (except for crp2, downregulated) were already constitutively highly expressed in skin from rag1 knockouts and only increased moderately after viral infection. Similar results were obtained for most mx isoforms (a reporter gene of the interferon response), suggesting a general overcompensation of the innate immunity in the absence of the adaptive one.

scholarly journals Accuracy of quantitative polymerase chain reaction in samples of frozen and paraffin-embedded healthy skin for the diagnosis of canine visceral leishmaniasis

2017 ◽  
Vol 69 (6) ◽  
pp. 1443-1450 ◽  
Author(s):  
M.P. Campos ◽  
M.F. Madeira ◽  
D.A. Silva ◽  
M.S. Solcà ◽  
O.M. Espíndola ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Quantitative Polymerase Chain Reaction ◽  
Healthy Skin ◽  
Sample Collection ◽  
Chain Reaction ◽  
Dna Recovery ◽  
Ffpe Samples ◽  
Fresh Frozen ◽  
Polymerase Chain ◽  
Commercial Kits

ABSTRACT The purpose of the present work was to evaluate the accuracy of quantitative polymerase chain reaction (qPCR) performed on samples of fresh frozen tissue (FT) and formalin-fixed, paraffin-embedded (FFPE) healthy skin. This is a validation study conducted with samples from 46 dogs from an endemic area in Brazil. After sample collection, DNA extractions were conducted using commercial kits and qPCR was oriented to kinetoplast DNA (kDNA) targets of the Leishmania infantum species. The results obtained for the FFPE samples showed 63.6% sensitivity and 77.1% specificity, whereas those obtained for the FT samples showed 100% and 48.6%, respectively. Poor agreement was observed for the results of the qPCR technique with FT and FFPE samples. Our results suggest freezing as the most suitable conservation method for the formation of sample databases considering DNA recovery

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