High titers of neutralizing antibodies in the blood fail to eliminate SARS‐CoV‐2 viral RNA in the upper respiratory tract

alexandrossfakianakis shared this article with you from Inoreader High titers of neutralizing antibodies in the blood fail to eliminate SARS‐CoV‐2 viral RNA in the upper respiratory tract via Journal of Medical Virology Abstract Retest positive SARS-CoV-2 viral RNA, as a unique phenomenon among the discharged individuals, has been demonstrated to be safe in the community. Still, the underlying mechanism of viral lingering is less investigated. In this study, first, we find that the frequency of viral RNA positive retest differs among variants. Higher ratios of viral RNA positive retest were more frequently observed among Delta (61.41%, 514 of 837 cases) and Omicrons (39.53%, 119 of 301 cases) infection than ancestral viral infection (7.27%, 21 of 289 cases). Second, the tissues where viral RNA reoccurred were altered. Delta RNA reoccurred mainly in the upper respiratory tract (90%), but ancestral virus RNA mainly in the gastrointestinal tract (71%). Third, vaccination did not reduce the frequency of viral RNA-positive retests, despite high concentrations of viral-specific antibodies in the blood. Finally, 37 of 55 (67.27%) Delta-infected patients receiving neutralizing antibody (nAb ) therapy become viral RNA retest positive when high concentrations of neutralizing antibodies still patrol in the blood. Altogether, our findings suggest that the presentence of high titers of neutralizing antibodies in the blood is incompetent in clearing residual viral RNA in the upper respiratory tract. This article is protected by copyright. All rights reserved. View on Web

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Characterization and application of a series of monoclonal antibodies against SARS‐CoV‐2 nucleocapsid protein

alexandrossfakianakis shared this article with you from Inoreader Characterization and application of a series of monoclonal antibodies against SARS‐CoV‐2 nucleocapsid protein via Journal of Medical Virology Abstract The ongoing coronavirus disease 2019 (COVID-19) pandemic has a significant global social and economic impact, and the emergence of new and more destructive mutant strains highlights the need for accurate virus detection. Here, 90 monoclonal antibodies (MAbs) that exclusively reacted with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid protein (NP) were generated. These MAbs did not cross-react with NPs of common human coronaviruses (HCoV, i.e., 229E, OC43, HKU1, and NL63) and Middle East Respiratory Syndrome Coronavirus. Subsequently, overlapped peptides in individual fragments (N1–N4) of NP were synthesized. N1-3 (25-GSNQNGERSGARSKQ-39), N3-1 (217-AALALLLLDRLNQL-230), and N4-8 (393-TLLPAADLDDFSKQL-407) were identified as major epitopes using enzyme-linked immunoassay (ELISA) and recognized by 47, 1, and 18 MAbs, respectively. The 24 remaining MAbs exhibited no reactivity with all synthetic peptides. Among MAb-epitope pairs, only MAbs targeting epitope N1-3 displayed no cross-reaction with NPs of SARS-CoV-1 and other SARS-related CoVs. All omicron variants contained a three-amino acid deletion (31ERS33) in the N1-3 region. Thus, MAbs targeting N1-3 failed to recognize these variants. Furthermore, a double-antibody sandwich ELISA for antigen detection was established using the optimal MAbs. Overall, a series of MAbs targeting SARS-CoV-2 NP was prepared, characterized with epitope mapping, and applied for the detection of SARS-CoV-2 antigens, and some novel B-cell epitopes of the viral NP were identified. This article is protected by copyright. All rights reserved. View on Web

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Effects of calcium hydroxide intracanal medicament on push‐out bond strength of endodontic sealers: A systematic review and meta‐analysis

alexandrossfakianakis shared this article with you from Inoreader Effects of calcium hydroxide intracanal medicament on push‐out bond strength of endodontic sealers: A systematic review and meta‐analysis via Journal of Esthetic and Restorative Dentistry Abstract Objective To investigate the effect of calcium hydroxide intracanal medicament on the push-out bond strength of resin-based and calcium silicate-based endodontic sealers. Methods A comprehensive search of was conducted for all relevant in-vitro studies. All randomized controlled in-vitro studies that evaluated the effect of calcium hydroxide on the push-out bond strength of resin-based or calcium silicate-based endodontic sealers were assessed. The variables of interest were extracted, and the risk of the included studies was evaluated. The standardized mean difference was calculated and the significance level was set at p value <0.05. Results A total of 26 studies were eligible for analysis. There were 45 independent comparison groups and 1009 recruited teeth. The pooled data showed no significant difference in push-out bond strength between calcium hydroxide and control group in the resin-based group (SMD = 0.03; 95% CI = −0.55, 0.60; p = 0.93), and calcium silicate-based group (SMD = 0.02; 95% CI = −0.31, 0.35; p = 0.90). Most of the studies (21 out of 26) were at medium risk of bias and five studies showed a low risk of bias. Conclusion The available evidence suggests that calcium hydroxide used as intracanal medication does not influence the push-out bond strength of the resin- and calcium silicate-based endodontic sealers. Clinical significance The results of this meta-analysis suggest that calcium hydroxide used as intracanal medication does not influence the push-out bond strength of resin-based and calcium silicate-based endodontic sealers. View on Web

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HBV REPLICATION DURING TENOFOVIR THERAPY IS FREQUENT IN HIV/HBV-COINFECTION

alexandrossfakianakis shared this article with you from Inoreader HBV REPLICATION DURING TENOFOVIR THERAPY IS FREQUENT IN HIV/HBV-COINFECTION via Clinical Infectious Diseases Advance Access ABSTRACT In the Swiss HIV Cohort Study, 61/222 (27%) HIV-suppressed persons with chronic hepatitis B virus (HBV) infection had HBV replication after two years on tenofovir, of whom 77% were suppressed thereafter. Self-reported adherence to therapy and HBV viral load at tenofovir initiation were predictors of persistent replication. View on Web

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Perfusion of microvascular free flaps in head and neck reconstruction after prior neck dissection and irradiation

alexandrossfakianakis shared this article with you from Inoreader Perfusion of microvascular free flaps in head and neck reconstruction after prior neck dissection and irradiation via International Journal of Oral and Maxillofacial Surgery via MedWorm.com Microvascular free flaps are frequently used for head and neck reconstruction after prior neck dissection (ND) and neck irradiation (RTX). The aim of this study was to investigate the influence of ND and RTX on flap perfusion as a critical factor for flap success. Overall, 392 patients reconstructed with a microvascular fasciocutaneous flap (FF) or perforator flap (PF) in the head and neck region between 2011 and 2020 were analysed retrospectively. Flap perfusion measured intraoperatively and postoperatively with the O2C tissue oxygen analysis system was compared between patients who had received neither ND nor RTX (controls), patients who had received ND but no RTX (ND group), and patients who had received both ND and RTX (ND+RTX group). (Source: International Journal of Oral and Maxillof... View on Web

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