Connexins within the rat larynx

2008 ◽  
Vol 139 (6) ◽  
pp. 823-828 ◽  
Author(s):  
Mark B. Van Deusen ◽  
Michael J. Lyon
Keyword(s):  
Polymerase Chain Reaction ◽  
American Academy ◽  
Head And Neck ◽  
Immunohistochemical Staining ◽  
Vocal Folds ◽  
Neck Surgery ◽  
Chain Reaction ◽  
Qrt Pcr ◽  
Laryngeal Mucosa ◽  
Polymerase Chain

Objectives/Hypothesis To determine the types and localization of connexins within the rat larynx. Study Design Quantitative real time polymerase chain reaction (qRT-PCR) of the epiglottis and laryngeal mucosa was used to identify connexins (Cx). Immunohistochemical labeling was then used to localize the Cxs within the larynx. Methods Twelve larynges from 3 to 4 month old Fisher-344 rats were used. RNA was extracted (N = 8) and cDNA produced. Primers for Cx26, Cx30, Cx32, Cx37, Cx40, and Cx43 were added and qRT-PCR performed. Others larynges were serially sectioned for immunohistochemistry. Results qRT-PCR revealed Cx43, Cx32, and Cx30 within the epiglottis and Cx43 in the vocal folds and Cx43 and Cx32 within the subglottic mucosa. Immunohistochemical staining confirmed these results. Conclusion The rat epiglottis is rich in Cx43, Cx32, and Cx30 whereas the vocal folds contain Cx43 and the subglottic mucosa Cx43 and Cx32. Their localizations suggest involvement in secretion for protective purposes and they may play a key role in laryngeal pathoses. © 2008 American Academy of Otolaryngology-Head and Neck Surgery Foundation. All rights reserved.

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 Quantitation of 35S Promoter in Maize DNA Extracts from Genetically Modified Organisms Using Real-Time Polymerase Chain Reaction, Part 2: Interlaboratory Study

2005 ◽  
Vol 88 (2) ◽  
pp. 558-573 ◽  
Author(s):  
Max Feinberg ◽  
Sophie Fernandez ◽  
Sylvanie Cassard ◽  
Chrystèle Charles-Delobel ◽  
Yves Bertheau ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Real Time ◽  
Genetically Modified Organisms ◽  
Genetically Modified ◽  
Interlaboratory Study ◽  
Performance Criteria ◽  
Tolerance Interval ◽  
Chain Reaction ◽  
Qrt Pcr ◽  
Polymerase Chain

Abstract The European Committee for Standardization (CEN) and the European Network of GMO Working Laboratories have proposed development of a modular strategy for stepwise validation of complex analytical techniques. When applied to the quantitation of genetically modified organisms (GMOs) in food products, the instrumental quantitation step of the technique is separately validated from the DNA extraction step to better control the sources of uncertainty and facilitate the validation of GMO-specific polymerase chain reaction (PCR) tests. This paper presents the results of an interlaboratory study on the quantitation step of the method standardized by CEN for the detection of a regulatory element commonly inserted in GMO maize-based foods. This is focused on the quantitation of P35S promoter through using the quantitative real-time PCR (QRT-PCR). Fifteen French laboratories participated in the interlaboratory study of the P35S quantitation operating procedure on DNA extract samples using either the thermal cycler ABI Prism® 7700 (Applied Biosystems, Foster City, CA) or Light Cycler® (Roche Diagnostics, Indianapolis, IN). Attention was focused on DNA extract samples used to calibrate the method and unknown extract samples. Data were processed according to the recommendations of ISO 5725 standard. Performance criteria, obtained using the robust algorithm, were compared to the classic data processing after rejection of outliers by the Cochran and Grubbs tests. Two laboratories were detected as outliers by the Grubbs test. The robust precision criteria gave values between the classical values estimated before and after rejection of the outliers. Using the robust method, the relative expanded uncertainty by the quantitation method is about 20% for a 1% Bt176 content, whereas it can reach 40% for a 0.1% Bt176. The performances of the quantitation assay are relevant to the application of the European regulation, which has an accepted tolerance interval of about ±50%. These data were fitted to a power model (r2 = 0.96). Thanks to this model, it is possible to propose an estimation of uncertainty of the QRT-PCR quantitation step and an uncertainty budget depending on the analytical conditions.

scholarly journals Head and Neck Practice in the COVID-19 Pandemics Today: A Rapid Systematic Review

2020 ◽  
Vol 24 (04) ◽  
pp. e518-e526
Author(s):  
Flavio Carneiro Hojaij ◽  
Lucas Albuquerque Chinelatto ◽  
Gustavo Henrique Pereira Boog ◽  
Júlia Adriana Kasmirski ◽  
João Vitor Ziroldo Lopes ◽  
...  
Keyword(s):  
Head And Neck ◽  
Antiviral Treatment ◽  
Epidemiological Data ◽  
Neck Surgery ◽  
Easy Access ◽  
Chain Reaction ◽  
Data Synthesis ◽  
Search Terms ◽  
Staff Protection ◽  
Polymerase Chain

Abstract Introduction Head and neck specialists and otorhinolaryngologists are greatly exposed to coronavirus disease 2019 (COVID-19) transmission in their everyday praxis. Many articles are being published regarding medical staff protection and patient management during the pandemic. Objective To provide an easy access to and a trustful review of the main aspects that have changed in the head and neck surgery and otorhinolaryngology practice due to the COVID-19 pandemic. Data Synthesis The search terms used were: (head and neck or otorhinolaryngology or ORL or thyroid) AND (severe acute respiratory syndrome coronavirus 2 [SARS-COV-2] or COVID-19 or CORONAVIRUS). The results were limited to the year of 2020. Articles were read in English, Portuguese, French, German, and Spanish or translated from Chinese. All included articles were read by at least two authors. Thirty-five articles were included. Most articles suggest postponing elective surgeries, with exception to cancer surgeries, which should be evaluated separately. Twenty-five articles recommended some kind of screening prior to surgery, using polymerase chain reaction (PCR) tests and epidemiological data. Extra precautions, such as use of personal protective equipment (PPE), are suggested for both tracheostomies and endoscopies. Fifteen articles give recommendation on how to use telemedicine. Conclusion The use of PPE (N95 or powered air-purifying respirator [PAPR]) during procedures should be mandatory. Patients should be evaluated about their COVID-19 status before hospital admission. Cancer should be treated. Tracheostomy tube cuff should be inflated inside the tracheal incision. All COVID-19 precautions should be kept until there is a validated antiviral treatment or an available vaccine.

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