Κυριακή 24 Ιουλίου 2022

Concordance of B and T cell responses to SARS‐CoV‐2 infection, irrespective of symptoms suggestive of COVID‐19

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Abstract

Objectives

To assess T cell responses in individuals with and without a positive antibody response to SARS-CoV-2, in symptomatic and asymptomatic individuals during the COVID-19 pandemic.

Methods

Participants were drawn from the TwinsUK cohort, grouped by a) presence or absence of COVID-associated symptoms (S+, S-), logged prospectively through the COVID Symptom Study app, and b) Anti-IgG Spike and anti-IgG Nucleocapsid antibodies measured by ELISA (Ab+, Ab-), during the first wave of the UK pandemic. T cell helper and regulatory responses after stimulation with SARS-CoV-2 peptides were assessed.

Results

32 participants were included in final analysis. 14 of 15 with IgG Spike antibodies had a T cell response to SARS-CoV-2-specific peptides; none of 17 participants without IgG Spike antibodies had a T cell response (Chi-squared 28.2, p<0.001). Quantitative T cell responses correlated strongly with fold-change in IgG Spike antibody titre (rho=0 .79, p<0.0001) but not to symptom score (rho=0.17, p=0.35).

Conclusions

Humoral and cellular immune responses to SARS-CoV-2 are highly correlated. We found no evidence of cellular immunity suggestive of SARS-CoV2 infection in individuals with a COVID-19-like illness but negative antibodies.

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Endoscopic trans‐lateral oropharyngeal wall approach to the petrous apex and the petroclival region

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Abstract

Background

A trans-lateral oropharyngeal wall approach (TLOWA) to the petrous apex has not been previously defined. This study aims to assess the feasibility of a TLOWA for surgical access to the petrous apex and the petroclival region.

Methods

An endoscopic TLOWA for exposure of the petrous apex and petroclival region was performed on five cadaveric specimens (10 sides). Associated anatomical landmarks were defined, and the strategies for maximal exposure of the internal carotid artery (ICA) were explored.

Results

Via a TLOWA, the parapharyngeal ICA was widely exposed in all 10 sides. Following transection of the Eustachian tube, the inferior petrous apex and petroclival region could be sufficiently exposed. After drilling the anteroinferior bony canal, the horizontal petrous ICA, foramen lacerum, and the paraclival ICA could be adequately revealed.

Conclusion

The TLOWA may provide an alternative corridor for access to the petrous apex and the petroclival region. The parapharyngeal, petrous, lower paraclival ICAs, and the foramen lacerum could be adequately exposed via the TLOWA.

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Sustained within-season vaccine effectiveness against influenza-associated hospitalization in children: Evidence from the New Vaccine Surveillance Network, 2015-2016 through 2019-2020

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Abstract
Background
Adult studies have demonstrated within-season declines in influenza vaccine effectiveness (VE); data in children are limited.
Methods
We conducted a prospective, test-negative study of children 6 months–17 years hospitalized with acute respiratory illness at 7 pediatric medical centers during the 2015-2016 through 2019-2020 influenza seasons. Case-patients were children with an influenza-positive molecular test matched by illness onset to influenza-negative control-patients. We estimated VE [100% x (1 – odds ratio)] by comparing the odds of receipt of ≥1 dose of influenza vaccine ≥14 days before illness onset among influenza-positive children to influenza-negative children. Changes in VE over time between vaccination date and illness onset date were estimated using multivariable logistic regression.
Results
Of 8,430 children, 4,653 (55%) received ≥1 dose of influenza vaccine. On average, 48% were v accinated through October and 85% through December each season. Influenza vaccine receipt was lower in case-patients than control-patients (39% vs. 57%, p < 0.001); overall VE against hospitalization was 53% (95% CI: 46%-60%). Pooling data across 5 seasons, the odds of influenza-associated hospitalization increased 4.2% (-3.2%-12.2%) per month since vaccination, with an average VE decrease of 1.9% per month (n = 4,000, p = 0.275). Odds of hospitalization increased 2.9% (95% CI: -5.4%-11.8%) and 9.6% (95% CI: -7.0%-29.1%) per month in children ≤8 years (n = 3,084) and 9-17 years (n = 916), respectively. These findings were not statistically significant.
Conclusions
We observed minimal, not statistically significant within-season declines in VE. Vaccination following current ACIP guidelines for timing of vaccine receipt remains the best strategy for preventing influenza-associated hospitalizations in children.
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Protection Against the Omicron Variant Offered by Previous SARS-CoV-2 Infection: A Retrospective Cohort Study

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Abstract
Background
Previous infection with SARS-CoV-2 provides strong protection against future infection. There is limited evidence on whether such protection extends to the Omicron variant.
Methods
This retrospective cohort study included 635,341 patients tested for SARS-CoV-2 via polymerase chain reaction (PCR) from 09 March 2020 to 01 March 2022. Patients were analyzed according to the wave in which they were initially infected. The primary outcome was reinfection during the Omicron period (20 December 2021, to 01 March 2022). We used a multivariable model to assess the effects of prior infection and vaccination on hospitalization.
Results
Among the patients tested during the Omicron wave, 30.6% tested positive. Protection of prior infection against reinfection with Omicron ranged from 18.0% (95% confidence interval [CI], 13.0-22.7) for patients infected in wave 1 to 69.2% (95% CI, 63.4-74.1) for those infected in the Delt a wave. In adjusted models, previous infection reduced hospitalization by 28.5% (95% CI, 19.1-36.7), while full vaccination plus a booster reduced it by 59.2% (95% CI, 54.8-63.1).
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DNA methylation subclasses predict the benefit from gross total tumor resection in IDH-wildtype glioblastoma patients

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Abstract
Background
DNA methylation-based tumor classification allows an enhanced distinction into subgroups of glioblastoma. However, the clinical benefit of DNA methylation-based stratification of glioblastomas remains inconclusive.
Methods
Multicentric cohort study including 430 patients with newly diagnosed glioblastoma subjected to global DNA methylation profiling. Outcome measures included overall survival (OS), progression-free survival (PFS), prognostic relevance of EOR and MGMT promoter methylation status as well as surgical benefit for recurrent glioblastoma.
Results
345 patients (80.2%) fulfilled the inclusion criteria. DNA methylation subclasses RTK I, RTK II, and mesenchymal (MES) revealed no significant survival differences (p = 0.06). 305 Patients receiving combined adjuvant therapy (RTK I: Ref. ; RTK II: HR 0.9 [95% CI, 0.64-1.28]; p = 0.56; MES: 0.69 [0.47-1.02]; p = 0.06). RTK I (GTR/near GTR: Ref.; PR: HR 2.87 [95% CI, 1.36-6.08]; p < 0.01) or RTK II (GTR/near GTR: Ref.; PR: HR 5.09 [95% CI, 2.80-9.26]; p < 0.01) tumors who underwent gross-total resection (GTR) or near GTR had a longer OS and PFS than partially resected patients. The MES subclass showed no survival benefit for a maximized EOR (GTR/near GTR: Ref.; PR: HR 1.45 [95% CI, 0.68-3.09]; p = 0.33). Therapy response-predictive value of MGMT promoter methylation was evident for RTK I (HR 0.37 [95% CI, 0.19-0.71]; p < 0.01) and RTK II (HR 0.56 [95% CI, 0.34-0.91]; p = 0.02) but not the MES subclass (HR 0.52 [95% CI, 0.27-1.02]; p = 0.06). For local recurrence (n=112), re-resection conveyed a progression-to-overall survival (POS) benefit (p < 0.01), which was evident in RTK I (p = 0.03) and RTK II (p < 0.01) tumors, but not in MES tumors (p = 0.33).
Conclusion
We demonstrate a survival benefit from maximized EOR for newly diagnosed and recurrent glioblastomas of the RTK I and RTK II but not the MES subclass. Hence, it needs to be debated whether the MES subclass should be treated with maximal surgical resection, especially when located in eloquent areas and at tim e of recurrence.
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A soluble DR5‐Fc chimeric protein (sDR5‐Fc) attenuates inflammatory responses induced by coronavirus MHV‐A59 and SARS‐CoV‐2

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Abstract

Mortality in COVID-19 patients has been linked to the presence of "cytokine storm" induced by SARS-CoV-2 infection, which involves elevated levels of circulating cytokines and immune-cell hyperactivation. Targeting cytokines during the management of COVID-19 patients has the potential to improve survival rates and reduce mortality. Although cytokine blockers and immune-host modulators are currently being tested in severely ill COVID-19 patients to cope with the overwhelming systemic inflammation, no significant efficacy has been observed yet, thus finding new cytokine blockers to attenuate the cytokine storm syndrome is meaningful. In this paper, we significantly attenuated the inflammatory responses induced by mouse hepatitis viruses A59 (MHV-A59) and SARS-CoV-2 through a soluble DR5-Fc (sDR5-Fc) chimeric protein that blocking the TRAIL-DR5 interaction. Our finding indicates that blocking TRAIL-DR5 pathway through sDR5-Fc chimeric protein is a promising strategy to treat with COVID-19 severe patients requiring ICU admission or with chronic metabolic diseases.

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Factors associated with high alanine aminotransferase (ALT) and cirrhosis in people living with HIV on combination antiretroviral treatment (cART) in the Asia‐Pacific

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Abstract

Introduction:

Liver disease is a growing burden among PLHIV in resource-limited settings. As an indicator of liver disease, risk factors of high alanine aminotransferase (ALT) and cirrhosis were assessed among PLHIV in the TREAT Asia HIV Observational Database (TAHOD).

Methods:

Patients on cART with a pre-cART ALT measurement and at least one follow-up ALT measurement were included. Factors associated with high ALT (ALT levels >5 times its upper limit of normal) were analysed using repeated measure logistic regression over a ten-year follow-up period. Liver cirrhosis was defined as having an APRI score >1.5, FIB-4 score >3.25, or a clinical diagnosis of cirrhosis. Cox regression analysis stratified by site was used to analyse factors associated with cirrhosis among those in follow-up after 2015.

Results:

Of 5182 patients, 101 patients (1.9%) had high ALT levels with HCV-antibody positive (OR 4.98, 95%CI 2.82-8.77, p <0.001) an d ever high alcohol consumption (OR 2.33, 95% CI 1.00-5.46, p=0.050) as likely factors. Among 6318 PLHIV in the liver cirrhosis analysis, 151 (2%) developed cirrhosis (incidence rate= 0.82 per 100 person-years). Those HCV-antibody positive (HR 5.54, 95% CI 3.75-8.18, p<0.001) and had high alcohol consumption (HR 2.06, 95%CI 1.23-3.45, p=0.006) were associated with liver cirrhosis.

Conclusion:

HCV-antibody positive and high alcohol consumption are factors associated with high ALT. With raised ALT levels as a known factor associated with liver cirrhosis, greater efforts are required in managing ALT levels and reduce the risk of developing liver cirrhosis among those positive for HCV-antibody and those who consume alcohol.

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Interferon‐gamma inducible protein 16 and type I interferon receptors expression in experimental apical periodontitis induced in wild type mice

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Abstract

Aim

The aim of this study was to evaluate the IFI16 and IFN-α/β receptors expression during the genesis and development of experimental apical periodontitis (AP) in mice teeth.

Methodology

AP was induced in the lower first molars of 40 C57BL/6 mice. They were divided according to the experimental periods 2, 7, 14, 21 and 42 days (n=8 per group). Five animals were used as a control group (without AP). Specimens were submitted to histological processing for description of the inflammatory process, immunostaining for the presence/absence and localization of IFI16 and IFN-α/β receptors (qualitative and semi-quantitative analysis), and tartrate-resistant acid phosphatase (TRAP) histoenzimology.

Results

The results showed a gradual development of AP over the experimental times. The expression of IFI16 was noticeably more exacerbated in the experimental early period (day 2) while the lowest expression was observed in the control group (p=0.02). For IFN-α/β receptors, a higher intensity staining was observed 42 days after AP induction, that was statistically different from the control group (p=0.02). Also, the number of TRAP positive cells was higher on the later periods (days 21 and 42) (p<0.001).

Conclusion

IFI16 protein expression was highest during the early periods after apical periodontitis induction in mice teeth, whilst IFN-α/β receptors expression was highest after apical periodontitis became established.

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Protective Effects of Cannabis sativa on chemotherapy‐induced nausea

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Abstract

Cyclophosphamide is an anticancer and immunosuppressive agent used in the treatment of various malignancies but causing gastrointestinal distress. Cannabis sativa (C. sativa) and its derivatives have been used for the treatment of human gastrointestinal disorders. A purpose of this study was to investigate the effect of C. sativa on nausea induced by cyclophosphamide in rats. The rats were divided into four groups (8 animals per group): Group 1: Normal control (saline i.p). Group 2: rats received cyclophosphamide (200 mg/kg i.p) 3 consecutive days. Group 3 and 4: Rats received cyclophosphamide (200 mg/kg ip) across days 1 – 7 and C. sativa (20 and 40 mg/kg sc) was administered on cyclophosphamide days 4 – 7. We examined intake of kaolin, normal food and changes in body weight, as an indicator of the emetic stimulus. Oxidative stress markers, antioxidant enzymes status, serotonin (5HT), dopamine, noradrenaline and CB1R levels were evaluated in the intestina l homogenate. Moreover, histopathological study was performed. Results showed that C. sativa ameliorates cyclophosphamide-induced emesis by increasing in body weight and normal diet intake with a decrease in kaolin diet intake after 7 days. Moreover, C. sativa significantly decreases (serotonin) 5HT, dopamine and noradrenaline, as well as, decreasing oxidative stress and inflammation. Administration of C. sativa significantly increased the expression of CB1R in intestinal homogenate. Treatment with C. sativa, also, improved the histological feature of an intestinal tissue. These results suggested that C. sativa possess antiemetic, antioxidant and anti-inflammatory effects in chemotherapy-induced nausea in rats by activating CB1R.

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Risk factor analysis for cytomegalovirus reactivation under prophylaxis with letermovir after allogeneic hematopoietic stem cell transplantation

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Abstract

Background

Letermovir has been approved as a novel cytomegalovirus (CMV) prophylactic agent after allogeneic hematopoietic stem cell transplantation (HSCT). However, there are still insufficient data to properly evaluate the real-world role of letermovir, and the risk factors for CMV reactivation under letermovir prophylaxis have not been clarified.

Methods

We performed a single-institution retrospective analysis of patients under prophylaxis with or without letermovir who underwent allogeneic HSCT between March 2012 and December 2019. In August 2018, letermovir was added to the clinical practice at our institution for the prophylaxis of CMV reactivation in allogeneic SCT recipients. Patients who underwent SCT without prophylactic letermovir from March 2012 until September 2018 served as a historical control.

Results

The cumulative incidence of clinically significant CMV infection (CS-CMVi) was significantly lower in the letermovir group than in the historical control group not receiving letermovir (30.2% vs 71.6%, P < 0.05, at 100 days). In addition, the cumulative incidence of non-relapse mortality (NRM) at day 500 was significantly lower in the letermovir group (4.7% vs 19.8%, P < 0.05). We then performed a risk factor analysis for developing CS-CMVi in the letermovir group. The only significant factor identified by this multivariable analysis was transplantation from a CMV seronegative donor to a seropositive recipient (HR = 2.76, 95% confidence interval 1.14 – 6.68, P < 0.05).

Conclusion

Our study showed that letermovir prophylaxis significantly reduced the incidence of CS-CMVi and NRM in a real-world setting and that the CMV serostatus of the donor remained as a risk factor for CS-CMVi even under letermovir prophylaxis.

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