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PubMed2000

Influenza virus infection in the second and third trimesters of pregnancy: a clinical and seroepidemiological study.

OBJECTIVE: To determine whether maternal influenza virus infection in the second and third trimesters of pregnancy results in transplacental transmission of infection, maternal auto-antibody production or an increase in complications of pregnancy. DESIGN: Case-control cohort study. POPULATION: Study and control cohorts were derived from 3,975 women who were consecutively delivered at two Nottingham teaching hospitals between May 1993 and July 1994. A complete set of three sera was available for 1,659 women. METHODS: Paired maternal ante- and postnatal sera were screened for a rise in anti-influenza virus antibody titre by single radial haemolysis and haemagglutination inhibition. Routine obstetric data collected during and after pregnancy were retrieved from the Nottingham obstetric database. Cord samples were tested for the presence of IgM anti-influenza antibodies, and postnatal infant sera were tested for the persistence of influenza-virus specific IgG. Paired antenatal and postnatal sera were tested against a standard range of auto-antigens by immunofluorescence. MAIN OUTCOME MEASURES: Classification of women as having definite serological evidence of an influenza virus infection in pregnancy (cases) or as controls. RESULTS: Intercurrent influenza virus infections were identified in 182/1,659 (11.0%) pregnancies. None of 138 cord sera from maternal influenza cases was positive for influenza A virus specific IgM. IgG anti-influenza antibodies did not persist in any of 12 infant sera taken at age 6-12 months. Six of 172 postnatal maternal sera from cases of influenza were positive for auto-antibodies. In all cases the corresponding antenatal serum was also positive for the same auto-antibody. There were no significant differences in pregnancy outcome measures between cases and controls. Overall, there were significantly more complications of pregnancy in the cases versus the controls, but no single type of complication achieved statistical significance. CONCLUSIONS: Influenza infection in the second and third trimesters of pregnancy is a relatively common event. We found no evidence for transplacental transmission of influenza virus or auto-antibody production in pregnancies complicated by influenza infections. There was an increase in the complications of pregnancy in our influenza cohort.

Adolescent↗
PubMed1985

[Detection of various papilloma virus types in cytologic smears of precancerous conditions and cancers of the uterine cervix].

DNA-in situ hybridisation on epithelial cells taken from cervical swabs of 101 different patients cytologically diagnosed as III D to V (Munich classification 1975) were performed using 32P-labelled DNA of the human papilloma virus (HPV) types 6, 11, 16 and 18 as smears. The following correlations between the cytological classification and DNA hybridisation were obtained: 55 out of 58 women (94.8%) having a normal Pap smear (Pap II) were negative by hybridisation as well, three cases contained HPV 6 or 11.59.3% of patients revealing abnormalities characteristic of a papillomavirus infection reacted with the 32P-labelled DNA, while HPV 6/11 or 16/18, respectively, occurred at approximately the same rate of frequency. In cases with severe dysplasia, carcinoma in situ or invasive cervical carcinoma (IVa, IVb, V) HPV 16 or 18 were more frequently found (67%) than in materials with mild dysplasia (IIID; 32% positive). HPV 6 or 11, on the other hand, was present only once in nine IVb/V-cases (11%), in 17% of IVa-cases, but in 32% of patients with mild dysplasia. Infections with all different virus types were found in 9% of the IVa-und 16% of the IIID-cases. The high prevalence of HPV 16 or 18 in CIS as well as in invasive carcinomas is in line with the biological correlation between both types of lesions. HPV 6 or 11 is more frequently associated with the usually reversible mild dysplastic epithelial alterations. The DNA-in situ swab hybridisation should, therefore, be of diagnostic value and might help to optimise the therapy for the individual patient.

Animals↗
PubMed1989

Evolutionary relationship between luteoviruses and other RNA plant viruses based on sequence motifs in their putative RNA polymerases and nucleic acid helicases.

Comparative studies of sequence motifs in the RNA polymerases and nucleic acid helicases of positive-sense RNA plant viruses have provided a new scheme for the classification of these pathogens. We propose a new luteovirus supergroup which should be added to the already described Sindbisvirus-like and picornavirus-like supergroups. Sequence motifs of nucleic acid helicases and RNA polymerases which previously were considered to be specific for each of the two supergroups now occur together within this new supergroup. We propose that this new viral supergroup provides an evolutionary link between the other two supergroups.

Amino Acid Sequence↗
PubMed1994

A case of neural cell adhesion molecule-positive peripheral T-cell lymphoma associated with human T-cell lymphotrophic virus type 1 showing an unusual involvement of the gastrointestinal tract during the course of the disease.

We report a case of neural cell adhesion molecule (NCAM)-positive peripheral T-cell lymphoma (PTCL), pleomorphic, medium and large cell type according to the updated Kiel classification, which was associated with human T-cell lymphotrophic virus type 1 (HTLV-1). The patient showed an unusual involvement of the gastrointestinal tract forming a bulky mass during the course of his disease, and a relatively indolent clinical course for 53 months until death. Phenotypic analysis showed CD2+, CD3-, CD4+, CD5+, CD7+, CD8-, CD16-, CD56+, and CD57- phenotype. Human T-cell lymphotrophic virus type 1 antibody was detected by the enzyme-linked immunosorbent assay. The proviral integration of HTLV-1 and the monoclonal rearrangements of T-cell receptor beta and gamma genes also were confirmed in DNA extract from fresh material. This fact calls attention to NCAM as one of the potential factors playing a role in the localization and behavior of lymphomas even within the category of PTCL associated with HTLV-1, ie, adult T-cell leukemia/lymphoma (ATLL).

Antigens, Surface↗
PubMedDate not supplied

The new lymphotropic herpesviruses (HHV-6, HHV-7, HHV-8) and hepatitis C virus (HCV) in human lymphoproliferative diseases: an overview.

Considerable evidence has been accumulating in favor of a possible involvement of viral agents in the pathogenesis of human lymphomas. The most recent proposal for a lymphoma classification, the Revised European-American Classification, emphasized for the first time the pathogenetic importance of two viruses, namely Epstein-Barr virus (EBV) and human T lymphotropic virus I (HTLV-I) in the development of certain lymphoid neoplasias. However, in the last ten years new viral agents possibly related to lymphoproliferative activity have been discovered: three herpesviruses [human herpesvirus-6 (HHV-6), -7 (HHV-7) and -8 (HHV-8)] and a flavivirus, HCV. HHV-6 was isolated from the peripheral blood of patients with lymphomas and a possible role for this beta-herpesvirus in Hodgkin's disease and in angioimmunoblastic lymphadenopathy (AILD) has emerged from serological and molecular studies. HHV-7, a beta-herpesvirus genetically close to HHV-6, has not yet been found in a human disease but it utilizes CD4 as a receptor on the lymphocyte surface. Only partial HHV-8 genomic sequences have been identified so far, suggesting a genetic homology with members of the gamma-herpesvirus family, including EBV. HHV-8 sequences have been identified for the first time in all forms of Kaposi's sarcoma as well as in a variety of lymphoid disorders, including body-cavity-based non Hodgkin's lymphomas, Castleman's disease, AILD and a type of HIV-negative reactive lymphadenopathy with peculiar histologic features. Finally, after its identification as the major cause of post-transfusion and sporadic non-A, non-B hepatitis, HCV has revealed a lymphotropism both in vitro and in vivo. A strong association between HCV infection and a benign lymphoproliferative disease, essential mixed cryoglobulinemia type II, has clearly emerged both from serological and molecular studies. A possible role for this viral infection in B-cell non Hodgkin's lymphomas not associated with cryoglobulinemia has also been proposed recently. The present work offers an overview of the huge amount of experimental and clinical observations supporting the possible involvement of these new lymphotropic viruses in human lymphoproliferative diseases.

Hepacivirus↗
PubMed1994

[HIV and dentistry. Part 3. HIV infection: pathogenesis, epidemiology, definitions and classification].

The acquired immunodeficiency syndrome (AIDS) is caused by a retrovirus, the human immunodeficiency virus (HIV), that selectively deteriorates cell-mediated immunity. Consequently fatal opportunistic infections and/or malignancies occur. In this paper the pathogenesis and the epidemiology of HIV infection are described. In addition the 1993 revised classification for HIV infection and the expanded surveillance case definition for AIDS are presented.

AIDS-Related Opportunistic Infections↗
PubMed1994

Fulminant hepatitis following bone marrow transplantation in hepatitis B virus carrier siblings.

A 19-year-old male healthy hepatitis B virus (HBV) carrier developed fulminant hepatitis following allogenic bone marrow transplantation (BMT) from his brother, who was also a healthy HBV carrier, during the first complete remission of acute myelogenic leukemia (M1, FAB classification). Serum markers related to both HBV and hepatitis C virus (HCV) were elevated during active liver injury when a point mutation in the precore (pre-C) region occurred in the HBV. The patient received low-dose interferon alpha (IFN-alpha), while the dose of cyclosporin A was tapered; the patient eventually recovered from the liver injury. Fulminant hepatitis due to HBV and/or HCV following BMT is rare, and it is considered to have a very poor prognosis. The rationale for the use of low-dose IFN-alpha with cyclosporin A (CyA) is discussed.

Adult↗
PubMed2002

Molecular classification of enteroviruses not identified by neutralization tests.

We isolated six viruses from patients diagnosed with aseptic meningitis or hand, foot, and mouth disease. The cytopathic effect of these viruses on cultured cells was like that of enteroviruses. However, viral neutralization tests against standard antisera were negative. Phylogenetic analysis with the complete VP4 nucleotide sequences of these 6 viruses and 29 serotypes of enteroviruses classified 3 of the viruses as serotype echovirus type 18 (EV18) and 3 as serotype human enterovirus 71 (HEV71). These results were confirmed by remicroneutralization tests with HEV-monospecific antisera or an additional phylogenetic analysis with the complete VP4 nucleotide sequences. Phylogenetic analysis with complete VP4 genes is more useful than neutralization tests with enterovirus serotype-specific antisera in identifying enterovirus serotypes.

Enterovirus↗
PubMed1984

Paramyxovirus type 1 infections of racing pigeons: 1 characterisation of isolated viruses.

Viruses isolated from field outbreaks of disease in racing pigeons in continental Europe and Great Britain were shown to be identical by serological tests using conventional chicken antisera and mouse monoclonal antibodies. The pigeon viruses showed high levels of cross-reaction to Newcastle disease virus (NDV) in haemagglutination inhibition tests and Madin-Darby bovine kidney cells infected with pigeon virus isolates bound three out of nine mouse monoclonal antibodies prepared against NDV Ulster 2C. These results confirm their classification in the paramyxovirus type 1 serotype of avian paramyxoviruses. However, the pigeon viruses could be distinguished from more classical paramyxovirus type 1 viruses by the significantly different titres obtained in haemagglutination inhibition tests, the failure of mouse monoclonal antibodies directed against the HN1 epitope of NDV Ulster 2C to inhibit their haemagglutinating activity and a unique binding pattern seen with the nine mouse monoclonal antibodies.

Animals↗
PubMed1990

Bovine virus diarrhoea virus: an introduction.

In view of the recently established genome organisation of pestiviruses, their classification as members of the togavirus family is no longer tenable. They should rather be provisionally considered as a new genus of the Flaviviridae, irrespective of differences in the nonstructural genes. Like other positive-stranded RNA viruses, pestiviruses are highly variable; apart from point mutations, recombinations are expected to contribute to their capricious behaviour. One trait of expected pathogenetic significance in infections with bovine virus diarrhoea virus is a change from the non-cytopathogenic to a cytopathogenic biotype. Cooperation of both variants in an animal to produce the severe disease picture known as mucosal disease is unique in virology; elucidation of this mechanism may shed light on the pathogenesis of other sporadic diseases with suspected viral origin.

Animals↗
PubMed1994

[Nodular and granulomatous form of periarteritis nodosa caused by the hepatitis B virus].

Polyarteritis nodosa (PAN) is, in rare cases, associated with subcutaneous nodules and pathology does not usually show the presence of peri and extravascular granulomas. When present in patients with hepatitis B virus (HBV) related PAN these facts demonstrate that classification of PAN is not homogeneous. CASE REPORT. A patient infected by HBV developed a PAN demonstrated by clinical symptoms and pathology. The disease was characterized by the presence of subcutaneous nodules and histologically by peri- and extra-vascular granuloma which surrounded necrosis of medium-sized vessels. Outcome was also unusual in the patient who did not respond to the association of plasma exchanges and antiviral agents and was only slightly improved by steroids and cyclophosphamide. COMMENTS. HBV-related PAN is considered to be an immune complex disorder. In the present case report granuloma were present as observed in Churg Strauss syndrome or Wegener's granulomatosis which are the consequence of other pathogenetic mechanisms as anticytoplasmic neutrophil antibodies (ANCA). This case reports underlines the heterogeneity of the PAN group of vasculitis and the probable role for various pathogenetic mechanisms.

Antiviral Agents↗
PubMed1995

Subtypes, genotypes and molecular epidemiology of the hepatitis B virus as reflected by sequence variability of the S-gene.

The serologic heterogeneity of the hepatitis B virus (HBV) has been established from immunodiffusion experiments for a long time. Four serotypes called subtypes of the hepatitis B surface antigen (HBsAg) have been defined by two mutually exclusive determinant pairs, d/y and w/r, and a common determinant a. These subtypes are adw, ayw, adr and ayr. By subdivision of the four major subtypes in the mid-70s, nine different subtypes were identified. Sequencing of viral genomes has now become a major goal of descriptive virology, and sequence data is now used to trace routes of infection, to reconstruct the phylogenetic history of viruses and two delimit genetic subtypes. A genetic classification based on the comparison of complete genomes has defined four genomic groups of HBV, later referred upon as genotypes, which were designated with A-D. However, the interrelation of the nine subtypes to the genotypes, the possible presence of more than four human HBV genotypes as well as their global geographical prevalence remained to be determined. By sequencing the S-gene of HBV the molecular basis was assessed for the serological variations of HBsAg within the major four subtypes. Thereby, also two new genotypes of HBV designated with E and F were identified. Complete genomic sequencing of E and F strains confirmed their status as new genotypes. The F genotype was found to diverge from other HBV genomes sequenced by 14%, thus being the most divergent HBV genome so far characterized. When the worldwide molecular epidemiology of HBV based on the variability of the S-gene was defined, the E and F strains seemed to originate in aboriginal populations of Africa and the New World, respectively. They shared a unique substitution at residue 140 in the second immunodominant loop of their encoded surface antigen when compared to the vaccine strain. Future research will establish whether this substitution may predispose to a vaccine escape mutant at residue 141, that now has been reported to occur in conjunction with the 140 substitution.

Demography↗
PubMed2005

Neuromuscular rehabilitation and electrodiagnosis. 2. Peripheral neuropathy.

UNLABELLED: This self-directed learning module highlights peripheral neuropathies. It is part of the chapter on neuromuscular rehabilitation and electrodiagnosis in the Self-Directed Physiatric Education Program for practitioners and trainees in physical medicine and rehabilitation. This article specifically focuses on diagnostic criteria and classifications of peripheral neuropathy, including diabetic, alcoholic, carcinomatous, human immunodeficiency virus-associated, and critical illness polyneuropathies. Treatment options are reviewed. The causes for difficult to obtain nerve conduction studies are highlighted. OVERALL ARTICLE OBJECTIVE: To summarize the diagnosis, classification, and treatment of peripheral neuropathies.

Antidepressive Agents, Tricyclic↗
PubMed1988

Early involvement of the nervous system by human immune deficiency virus (HIV). A study of 79 patients.

We report on 79 patients of different stages of human immune deficiency virus (HIV) infection according to the Walter-Reed staging classification (WR). Comparing the HIV antibody content per weight IgG in serum and cerebrospinal fluid (CSF), 54 patients (68%) showed higher antibody activity in CSF than in serum, indicating intrathecal antibody production and thus a local challenge with the virus. The percentage of patients with these antibodies in CSF increased from stage WR 1 (33%) to WR 5 (90%). It decreased again in WR 6 (68%). Twenty-one patients with intrathecally produced antibodies but without evidence for opportunistic or preexistent neuropsychiatric diseases were further analyzed. Even in stages WR 1 and 2 these patients showed distinct clinical signs. These consisted mostly in apathic personality change (n = 13), peripheral neuropathy (n = 8) or mild hemisyndrome (n = 9). Progression to severe dementia solely caused by HIV encephalitis seems to be possible. More often acceleration of the mental disorder indicates a synergistic action of other pathogens. Our study gives further evidence for very frequent, early and clinically active involvement of the nervous system by the HIV infection.

Acquired Immunodeficiency Syndrome↗