64 research outputs found
Animal models and vaccines for SARS-CoV infection
We summarize findings of SARS-CoV infections in several animal models each of which support viral replication in lungs accompanied by histopathological changes and/or clinical signs of illness to varying degrees. New findings are reported on SARS-CoV replication and associated pathology in two additional strains (C57BL/6 and 129S6) of aged mice. We also provide new comparative data on viral replication and associated pathology following infection of golden Syrian hamsters with various SARS-CoV strains and report the levels of neutralizing antibody titers following these infections and the cross-protective efficacy of infection with these strains in protecting against heterologous challenge. Finally, we summarize findings of a variety of vaccine approaches and discuss the available in vitro and in vivo data addressing the potential for disease enhancement following re-infection in animals previously vaccinated against or infected with SARS-CoV
Monkeypox Transmission and Pathogenesis in Prairie Dogs
During May and June 2003, the first cluster of human monkeypox cases in the United States was reported. Most patients with this febrile vesicular rash illness presumably acquired the infection from prairie dogs. Monkeypox virus was demonstrated by using polymerase chain reaction in two prairie dogs in which pathologic studies showed necrotizing bronchopneumonia, conjunctivitis, and tongue ulceration. Immunohistochemical assays for orthopoxviruses demonstrated abundant viral antigens in surface epithelial cells of lesions in conjunctiva and tongue, with less amounts in adjacent macrophages, fibroblasts, and connective tissues. Viral antigens in the lung were abundant in bronchial epithelial cells, macrophages, and fibroblasts. Virus isolation and electron microscopy demonstrated active viral replication in lungs and tongue. These findings indicate that both respiratory and direct mucocutaneous exposures are potentially important routes of transmission of monkeypox virus between rodents and to humans. Prairie dogs offer insights into transmission, pathogenesis, and new vaccine and treatment trials because they are susceptible to severe monkeypox infection
Neuroinvasion by Mycoplasma pneumoniae in Acute Disseminated Encephalomyelitis
We report the autopsy findings for a 45-year-old man with polyradiculoneuropathy and fatal acute disseminated encephalomyelitis after having Mycoplasma pneumoniae pneumonia. M. pneumoniae antigens were demonstrated by immunohistochemical analysis of brain tissue, indicating neuroinvasion as an additional pathogenetic mechanism in central neurologic complications of M. pneumoniae infection
Joint ESPGHAN/NASPGHAN Guidelines for the Management of Helicobacter pylori in Children and Adolescents ( Update 2016)
Background: Because of the changing epidemiology of Helicobacter pylori infection and low efficacy of currently recommended therapies, an update of the European Society for Paediatric Gastroenterology Hepatology and Nutrition/North American Society for Pediatric Gastroenterology, Hepatology and Nutrition recommendations for the diagnosis and management of H pylori infection in children and adolescents is required. Methods: Asystematic review of the literature (time period: 2009-2014) was performed. Representatives of both societies evaluated the quality of evidence using GRADE (Grading of Recommendation Assessment, Development, and Evaluation) to formulate recommendations, which were voted upon and finalized using a Delphi process and face-to-face meeting. Results: The consensus group recommended that invasive diagnostic testing for Hpylori be performed only when treatment will be offered if tests are positive. To reach the aim of a 90% eradication rate with initial therapy, antibiotics should be tailored according to susceptibility testing. Therapy should be administered for 14 days, emphasizing strict adherence. Clarithromycin-containing regimens should be restricted to children infected with susceptible strains. When antibiotic susceptibility profiles are not known, high-dose triple therapy with proton pump inhibitor, amoxicillin, and metronidazole for 14 days or bismuth-based quadruple therapy is recommended. Success of therapy should be monitored after 4 to 8 weeks by reliable noninvasive tests. Conclusions: The primary goal of clinical investigation is to identify the cause of upper gastrointestinal symptoms rather than H pylori infection. Therefore, we recommend against a test and treat strategy. Decreasing eradication rates with previously recommended treatments call for changes to first-line therapies and broader availability of culture or molecular-based testing to tailor treatment to the individual child
Histopathologic Improvement with Lymphedema Management, Léogâne, Haiti
Basic management improves the histologic profile of limbs in patients with filarial lymphedema
Severe Histoplasmosis in Travelers to Nicaragua
We investigated an outbreak of unexpectedly severe histoplasmosis among 14 healthy adventure travelers from the United States who visited a bat-infested cave in Nicaragua. Although histoplasmosis has rarely been reported to cause serious illness among travelers, this outbreak demonstrates that cases may be severe among travelers, even young, healthy persons
Histopathologic Features of Mycobacterium ulcerans Infection
Because of the emergence of Buruli ulcer disease, the World Health Organization launched a Global Buruli Ulcer Initiative in 1998. This indolent skin infection is caused by Mycobacterium ulcerans. During a study of risk factors for the disease in Ghana, adequate excisional skin-biopsy specimens were obtained from 124 clinically suspicious lesions. Buruli ulcer disease was diagnosed in 78 lesions since acid-fast bacilli (AFB) were found by histopathologic examination. Lesions with other diagnoses included filariasis (3 cases), zygomycosis (2 cases), ulcerative squamous cell carcinomas (2 cases), keratin cyst (1 case), and lymph node (1 case). Thirty-seven specimens that did not show AFB were considered suspected Buruli ulcer disease cases. Necrosis of subcutaneous tissues and dermal collagen were found more frequently in AFB-positive specimens compared with specimens from suspected case-patients (p<0.001). Defining histologic criteria for a diagnosis of Buruli ulcer disease is of clinical and public health importance since it would allow earlier treatment, leading to less deforming sequelae
Mechanisms by which the cystic fibrosis transmembrane conductance regulator may influence SARS-CoV-2 infection and COVID-19 disease severity
Patients with cystic fibrosis (CF) exhibit pronounced respiratory damage and were initially considered among those at highest risk for serious harm from SARS-CoV-2 infection. Numerous clinical studies have subsequently reported that individuals with CF in North America and Europe—while susceptible to severe COVID-19—are often spared from the highest levels of virus-associated mortality. To understand features that might influence COVID-19 among patients with cystic fibrosis, we studied relationships between SARS-CoV-2 and the gene responsible for CF (i.e., the cystic fibrosis transmembrane conductance regulator, CFTR). In contrast to previous reports, we found no association between CFTR carrier status (mutation heterozygosity) and more severe COVID-19 clinical outcomes. We did observe an unexpected trend toward higher mortality among control individuals compared with silent carriers of the common F508del CFTR variant—a finding that will require further study. We next performed experiments to test the influence of homozygous CFTR deficiency on viral propagation and showed that SARS-CoV-2 production in primary airway cells was not altered by the absence of functional CFTR using two independent protocols. On the contrary, experiments performed in vitro strongly indicated that virus proliferation depended on features of the mucosal fluid layer known to be disrupted by absent CFTR in patients with CF, including both low pH and increased viscosity. These results point to the acidic, viscous, and mucus-obstructed airways in patients with cystic fibrosis as unfavorable for the establishment of coronaviral infection. Our findings provide new and important information concerning relationships between the CF clinical phenotype and severity of COVID-19.This work was supported by the Italian Ministry of Health (Ministero della Salute) [Ricerca Finalizzata RF-2016-02364358]; Fondazione IRCCS Ca′ Granda Ospedale Maggiore Policlinico, Ricerca corrente; Fondazione IRCCS Ca′ Granda core COVID-19 Biobank [RC100017A]; “Liver BIBLE” [PR-0391]; and Innovative Medicines Initiative 2 joint undertaking of the European Union (EU) Horizon 2020 research and innovation programme and European Federation of Pharmaceutical Industries and Associations Programme Horizon 2020 [under grant agreement No. 777377] for the project LITMUS and the European Union, programme “Photonics” [under grant agreement 101016726] to LV. JCH was funded by the Research Council of Norway [grant no 312780] and a philanthropic donation from Vivaldi Invest A/S owned by Jon Stephenson von Tetzchner. The funders had no role in study design, data collection, data analysis, data interpretation, or writing of the report. AF was supported by a grant from the German Federal Ministry of Education and Research [01KI20197]. This work was also funded by a generous philanthropic donation from Banca Intesa San Paolo to RA. This study makes use of data generated by the GCATI Genomes for Life. Cohort study of the Genomes of Catalonia from Institut Germans Trias I Pujol (IGTP); IGTP is part of the CERCA Program/Generalitat de Catalunya. GCAT is supported by Acción de Dinamización del ISCIII-MINECO and the Ministry of Health of the Generalitat of Catalunya [ADE 10/00026], with additional support by the Agència de Gestió d'Ajuts Universitaris i de Recerca (AGAUR) [2017-SGR 529], National Grant [PI18/01512], and VEIS project [001-P-001647], co-funded by European Regional Development Fund (ERDF), “A way to build Europe.” EdW and BNW were supported by the Intramural Research Program, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH). PRT and SGS received funding from NIH NIAID [R01 AI167356].Peer reviewe
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