Search results for "INFECTIONS"
showing 10 items of 2671 documents
New chimaeric hepatitis B virus core particles carrying hantavirus (serotype Puumala) epitopes: immunogenicity and protection against virus challenge
1999
Virus-like particles generated by the heterologous expression of virus structural proteins are able to potentiate the immunogenicity of foreign epitopes presented on their surface. In recent years epitopes of various origin have been inserted into the core antigen of hepatitis B virus (HBV) allowing the formation of chimaeric HBV core particles. Chimaeric core particles carrying the 45 N-terminal amino acids of the Puumala hantavirus nucleocapsid protein induced protective immunity in bank voles, the natural host of this hantavirus. Particles applied in the absence of adjuvant are still immunogenic and partially protective in bank voles. Although a C-terminally truncated core antigen of HBV…
Chimaeric HBV core particles carrying a defined segment of Puumala hantavirus nucleocapsid protein evoke protective immunity in an animal model
1998
Abstract Hantaviruses are rodent-born agents which are pathogenic in humans causing haemorrhagic fever with renal syndrome or hantavirus pulmonary syndrome. To induce a protective immunity against a European hantavirus (Puumala) we constructed chimaeric hepatitis B virus (HBV) core particles carrying defined fragments of the Puumala virus nucleocapsid protein. After immunisation of bank voles, the natural host of Puumala virus, with core particles possessing an insertion of the N-terminal part of Puumala virus nucleocapsid protein, four of five animals were protected against subsequent virus challenge. The results show that the major protective region of the nucleocapsid protein is located …
An amino-terminal segment of hantavirus nucleocapsid protein presented on hepatitis B virus core particles induces a strong and highly cross-reactive…
2004
AbstractPreviously, we have demonstrated that hepatitis B virus (HBV) core particles tolerate the insertion of the amino-terminal 120 amino acids (aa) of the Puumala hantavirus nucleocapsid (N) protein. Here, we demonstrate that the insertion of 120 amino-terminal aa of N proteins from highly virulent Dobrava and Hantaan hantaviruses allows the formation of chimeric core particles. These particles expose the inserted foreign protein segments, at least in part, on their surface. Analysis by electron cryomicroscopy of chimeric particles harbouring the Puumala virus (PUUV) N segment revealed 90% T = 3 and 10% T = 4 shells. A map computed from T = 3 shells shows additional density splaying out …
An international perspective on hospitalized patients with viral community-acquired pneumonia
2019
Background Who should be tested for viruses in patients with community acquired pneumonia (CAP), prevalence and risk factors for viral CAP are still debated. We evaluated the frequency of viral testing, virus prevalence, risk factors and treatment coverage with oseltamivir in patients admitted for CAP. Methods Secondary analysis of GLIMP, an international, multicenter, point-prevalence study of hospitalized adults with CAP. Testing frequency, prevalence of viral CAP and treatment with oseltamivir were assessed among patients who underwent a viral swab. Univariate and multivariate analysis was used to evaluate risk factors. Results 553 (14.9%) patients with CAP underwent nasal swab. Viral CA…
Seasonal Human Coronavirus Respiratory Tract Infection in Recipients of Allogeneic Hematopoietic Stem Cell Transplantation
2021
Abstract Background Little is known about characteristics of seasonal human coronaviruses (HCoVs) (NL63, 229E, OC43, and HKU1) after allogeneic stem cell transplantation (allo-HSCT). Methods This was a collaborative Spanish and European bone marrow transplantation retrospective multicenter study, which included allo-HSCT recipients (adults and children) with upper respiratory tract disease (URTD) and/or lower respiratory tract disease (LRTD) caused by seasonal HCoV diagnosed through multiplex polymerase chain reaction assays from January 2012 to January 2019. Results We included 402 allo-HSCT recipients who developed 449 HCoV URTD/LRTD episodes. Median age of recipients was 46 years (range,…
Risk factors for bronchiolitis hospitalization during the first year of life in a multicenter Italian birth cohort
2015
Background: Respiratory Syncytial Virus (RSV) is one of the main causes of respiratory infections during the first year of life. Very premature infants may contract more severe diseases and 'late preterm infants' may also be more susceptible to the infection. The aim of this study is to evaluate the risk factors for hospitalization during the first year of life in children born at different gestational ages in Italy. Methods: A cohort of 33-34 weeks gestational age (wGA) newborns matched by sex and age with two cohort of newborns born at 35-37 wGA and >37 wGA were enrolled in this study for a three-year period (2009-2012). Hospitalization for bronchiolitis (ICD-9 code 466.1) during the f…
Bronchiolitis: The New American Academy of Pediatrics Guidelines
2008
Respiratory Syncytial Virus (RSV) is the leading cause of hospitalization for lower respiratory tract infections (LRTI) in young children worldwide. RSV is an important cause of LRTI in infants and a variety of factors, such as gender, age at admission, gestational age, birth weight, and exposure to tobacco smoke and breast feeding may affect the prevalence of RSV-related disease and, possibly, the risk of developing asthma-like symptoms during the school years. AAP in 2006 formulated the new guidelines on diagnosis and management of bronchiolitis, giving recommendations on different conditions requesting clinical decisions also in terms of prevention.
Detection of Human Immunodeficiency Virus-1 Nucleic Acid on Inactivated Filter Paper Disks by Polymerase Chain Reaction and Microtiter Plate Assay
1994
Human immunodeficiency virus type 1 (HIV-1) in cultured cells, peripheral blood samples and sera were adsorbed on filter paper disks and inactivated by heat or ethanol. Two procedures, the polymerase chain reaction (PCR) and microtiter plate assay (HMPA) were used to detect the nucleic acid. The sensitivity after different heat treatments with nested PCR for HIV-1 DNA (or nested reverse transcription-PCR for HIV-1 RNA) was identical regardless of whether the samples were examined immediately or one month later. Inactivation by ethanol treatment resulted in a slight loss of sensitivity. The HMPA proved to be as reliable and specific as the conventional PCR technique. We conclude that the hea…
Effect of pulp and paper mill effluent (BKME) on physiological parameters of roach (Rutilus rutilus) infected by the digenean Rhipidocotyle fennica.
2002
Physiological parameters were measured after experimental infection of roach (Rutilus rutilus L.) with Rhipidocotyle fennica Gibson, Valtonen et Taskinen, 1992 (Digenea) cercariae. The fish were caught from two lakes: a eutrophic bleached kraft mill effluent (BKME)-contaminated lake and an oligotrophic unpolluted lake. The intensity of infection was followed up to 10 days post infection (p.i.) and physiological parameters indicating non-specific stress responses and the condition of fish were examined simultaneously. The mean abundance, the number of parasites per fish, of R. fennica was significantly higher in the fish from the contaminated water during the first two days p.i., probably re…
Patterns of cercarial production from Diplostomum spathaceum: terminal investment or bet hedging?
2004
In the production of the infective cercariae of trematodes, the terminal investment hypothesis of life-history theory predicts that the rate of host exploitation and cercarial production should increase during the period of cercarial shedding since the reproductive value of the parasite decreases during this period. In contrast, a bet hedging hypothesis that focuses on the success of transmission when host contact rate is variable predicts that cercarial production should decrease in an attempt to keep the host alive for longer and thus would increase the probability of successful transmission. We examined these two hypotheses under laboratory conditions and recorded the production ofDiplos…