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《Vaccine》2021,39(40):5729-5731
IntroductionConcerns were raised over an increase in Bell's palsy, herpes simplex and herpes zoster after BNT162b2 vaccination, all are manifestations of herpesviruses reactivation. As herpesviruses commonly reactivate in the oropharynx, we have hypothesized that oropharyngeal shedding of herpesviruses will increase after vaccination.MethodsImmune-competent Adults, excluding those using topical steroids or manifesting symptomatic herpesvirus infection, were sampled before BNT162b2 vaccination and one week after. Herpesviruses 1–7 shedding was tested with a multiplexed PCR.ResultsIn 103 paired samples the prevalence of herpesviruses was similar before and after vaccination: HSV1, 3.9% vs. 5.8% (p = 0.75); HSV2, 0% vs. 1% (p = not applicable, NA); VZV, 0% vs. 0% (p = NA); EBV, 14.6% vs. 17.5% (p = 0.63); CMV, 0% vs. 0% (p = NA); HHV6, 4.9% vs. 7.8% (p = 0.55); HHV7, 71.8% vs. 72.8% (p = 1); any herpesvirus, 73.8% vs. 74.8% (p = 1).DiscussionWe did not find evidence for increased oropharyngeal reactivation of herpesviruses one week after BNT162b2.  相似文献   
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《Vaccine》2019,37(44):6696-6706
Live attenuated viral vaccine/vector candidates are inherently unstable and infectivity titer losses can readily occur without defining appropriate formulations, storage conditions and clinical handling practices. During initial process development of a candidate vaccine against HIV-1 using a recombinant Human Cytomegalovirus vector (rHCMV-1), large vector titer losses were observed after storage at 4 °C and after undergoing freeze-thaw. Thus, the goal of this work was to develop candidate frozen liquid formulations of rHCMV-1 with improved freeze-thaw and short-term liquid stability for potential use in early clinical trials. To this end, a virus stability screening protocol was developed including use of a rapid, in vitro cell-based immunofluorescence focus assay to quantitate viral titers. A library of ∼50 pharmaceutical excipients (from various known classes of additives) were evaluated for their effect on vector stability after freeze-thaw cycling or incubation at 4 °C for several days. Certain additives including sugars and polymers (e.g., trehalose, sucrose, sorbitol, hydrolyzed gelatin, dextran 40) as well as removal of NaCl (lower ionic strength) protected rHCMV-1 against freeze-thaw mediated losses in viral titers. Optimized solution conditions (e.g., solution pH, buffers and sugar type) slowed the rate of rHCMV-1 titer losses in the liquid state at 4 °C. After evaluating various excipient combinations, three new candidate formulations were designed and rHCMV-1 stability was benchmarked against both the currently-used and a previously reported formulation. The new candidate formulations were significantly more stable in terms of reducing rHCMV-1 titer losses after 5 freeze-thaw cycles or incubation at 4 °C for 30 days. This case study highlights the utility of semi-empirical design of frozen liquid formulations of a live viral vaccine candidate, where protection against infectivity titer losses due to freeze-thaw and short-term liquid storage are sufficient to enable more rapid initiation of early clinical trials.  相似文献   
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Abstract

Background: Cytomegalovirus (CMV) is rarely thought to be the cause of significant gastrointestinal infection in immunocompetent children. CMV colitis is seldom observed in young infants. This study aims to examine the clinical features of CMV colitis in Chinese children.

Methods: Patients with infantile onset CMV colitis diagnosed in intestinal tissue at Children’s Hospital of Fudan University from 1st January 2017, to 31st January 2019 were enrolled. Clinical data were retrieved from medical records, and the literature on infant CMV colitis was also reviewed.

Results: Ten patients were included with a median age of 2.5?months [interquartile range 2.0, 6.3?months]. All 10 patients had diarrhea, 10 patients had anemia, seven patients reported hematochezia, five patients had hypoalbuminemia, five patients had retinitis, two patients had hearing impairment, and one patient had perianal abscess and anal fistula. The patients had punched-out ulcerations, longitudinal ulcerations or irregular ulcerations on the rectum and/or colon. Typical histologic evaluation showed crypt distortion and inflammatory infiltration. CMV inclusion bodies were noted in four patients. Immunohistochemistry on intestinal tissue was performed to diagnose CMV, with all patients positive. After follow-up, all patients are clinically recovered or in remission; six patients received antiviral therapy, and five patients had healed ulcers on endoscopic examination.

Conclusions: CMV colitis might be a rare cause of intractable diarrhea in immunocompetent children. Clinicians should be aware of the possibility of CMV colitis in patients with intractable diarrhea.  相似文献   
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Immunosuppressive agents have enabled the development of allogenic transplantation during the last 40 years, allowing considerable improvement in graft survival. However, several issues remain such as the nephrotoxicity of calcineurin inhibitors, the cornerstone of immunosuppressive regimens and/or the higher risk of opportunistic infections and cancers. Most immunosuppressive agents target T cell activation and may not be efficient enough to prevent allo-immunization in the long term. Finally, antibody mediated rejection due to donor specific antibodies strongly affects allograft survival.Many drugs have been tested in the last decades, but very few have come to clinical use. The most recent one is CTLA4-Ig (belatacept), a costimulation blockade molecule that targets the second signal of T cell activation and is associated with a better long term kidney function than calcineurin inhibitors, despite an increased risk of acute cellular rejection.The research of new maintenance long-term immunosuppressive agents focuses on costimulation blockade. Agents inhibiting CD40-CD40 ligand interaction may enable a good control of both T cells and B cells responses. Anti-CD28 antibodies may promote regulatory T cells. Agents targeting this costimulation pathways are currently evaluated in clinical trials.Immunosuppressive agents for ABMR treatment are scarce since anti-CD20 agent rituximab and proteasome inhibitor bortezomib have failed to demonstrate an interest in ABMR. New drugs focusing on antibodies removal (imlifidase), B cell and plasmablasts (anti-IL-6/IL-6R, anti-CD38…) and complement inhibition are in the pipeline, with the challenge of their evaluation in such a heterogeneous pathology.  相似文献   
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Cytomegalovirus (CMV) retinitis in hematologic malignancies in the absence of hematopoietic cell transplant (HCT) is uncommon. We report a case of a 54‐year‐old woman with peripheral T‐cell lymphoma who develops CMV retinitis and subsequently undergoes an autologous HCT, with eventual development of immune reconstitution uveitis. We further reviewed the PubMed literature on CMV retinitis in patients with lymphoma. We describe that CMV retinitis in patients with lymphoma has variable clinical presentations, may occur at any time during the course of the disease and chemotherapy, and is associated with significant morbidity.  相似文献   
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ABSTRACT

Purpose

To determine the prevalence of viral infections in patients with hypertensive anterior uveitis in Thailand from polymerase chain reaction (PCR) of aqueous humor.  相似文献   
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