Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “virus classification”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,009 records · Page 56Linked to original sources
PubMed1987

Refinement and precision in the classification of murine lymphomas by genotyping with immunoglobulin and T cell receptor probes.

Of 114 murine leukemia virus induced lymphomas and 12 lymphoid hyperplasias, T cell receptor beta-chain gene and immunoglobulin gene constellation (immunogenotype) was compared with histology and surface marker expression (immunomorphology). In 53 out of 114 lymphomas (45%), definite conclusions concerning cell lineage were possible only after genotyping. Fifteen follicular center cell lymphomas with a clear phenotype (13 tumors with B and 2 tumors with T cell markers) were genotypically classified in agreement with their phenotype. Of another 21 follicular center cell tumors (12 null cell tumors lacking T or B cell-specific antigens and 9 tumors phenotypically composed of mixtures of T and B cells), B cell lineage was determined upon genotyping in 17 cases. All 41 lymphoblastic tumors with a T cell phenotype and 6 out of 7 lymphoblastic tumors with a T cell phenotype and 6 out of 7 lymphoblastic tumors with a B cell phenotype, upon DNA analysis were indeed classified as T and B cell tumors, respectively. Of another 10 lymphoblastic tumors (phenotypically 4 null cell lymphomas, 6 mixtures of T and B cells) genotyping established lineage in 9 cases. Fifteen lymphoblastic neoplasms showing lineage infidelity because of simultaneous expression of a T (Thy-1) and a B cell (B220) marker were clearly of T cell genotype. Only 4 out of 114 lymphomas tested retained both Ig and T cell receptor genes in germline configuration, although 6 lymphomas in these series had both Ig and T cell receptor genes rearranged. Four of twelve lesions histologically classified as hyperplasias nevertheless contained a monoclonal B cell population at the DNA level. Immunogenotypic evaluation of lymphomas allows precise lymphoma lineage determination even in cases where marker analysis falls short, and is clearly superior in detecting mono- or oligoclonality in lymphomas versus polyclonality in benign lesions.

Animals↗
PubMed1987

[Polyclonal B cell activation in infection caused by human immunodeficiency virus (HIV)].

87 patients with anti-HIV antibodies were divided into three groups based on the classification of the Centers for Disease Control and the following parameters reflecting polyclonal B cell activation were evaluated in these patients: immunoglobulin levels, circulating immune complexes and occurrence of autoantibodies. The results reported here indicate that intense polyclonal B cell activation occurs in both asymptomatic (CDC 2) and symptomatic patients (CDC 3 and CDC 4). Moreover, serological abnormalities were detected with similar frequency in the three groups studied.

Acquired Immunodeficiency Syndrome↗
PubMed1951

A new member of the psittacosis-lymphogranuloma group of viruses that causes infection in calves.

From portions of intestine and feces of apparently normal calves, a virus that produces elementary bodies was procured in guinea pigs and in embryonated eggs. Morphologically and tinctorially this virus closely resembled members of the psittacosis-lymphogranuloma group of viruses and it shared a common antigen or antigens with them. Comparison of serological, pathogenic, and other properties indicated that this virus from calves is a new member of the psittacosis-lymphogranuloma group and in keeping with classification practices it is provisionally named Miyagawanella bovis. Miyagawanella bovis when fed to experimental calves established an infection in the intestinal tract that resembled the inapparent infection seen in natural cases but failed to produce evident disease. Ability of the virus to infect experimental animals by feeding, and its presence in feces of infected animals indicate its natural mode of spread. This method of dissemination and persistence of virus for long periods of time in infected animals suggested the virus should be widespread and more than 60 per cent of the calves in the vicinity of lthaca were found to be infected.

Animals↗
PubMed1992

Cytokine-mediated regulation of monocyte/macrophage cytotoxicity in human immunodeficiency virus-1 infection.

Monocyte/macrophage-mediated tumor cytotoxicity was studied in patients infected with human immunodeficiency virus-1 (HIV-1) at various stages [Center for disease control (CDC) classification] of the disease. using the P-815 tumor cell line as target cells, the results demonstrated reduced monocyte/macrophage cytotoxicity early in HIV-1-related disease (CDCIII, P < 0.01). This cellular dysfunction sustained during the progression of the disease. Evidence could be presented that neither exogenous application of macrophage-stimulating cytokines (e.g. interferons) nor their endogenous induction in vitro restored monocyte/macrophage cytotoxicity. However, enhanced tumor necrosis factor (TNF)-alpha production, which parallels the observed reduced capacity to lyse P-815 tumor cells, might be the major source for monocyte/macrophage-mediated cell lysis. TNF-alpha-induced cytotoxicity can be inhibited by addition of anti-TNF-alpha. Other experimental models using TNF-sensitive tumor target cells may, therefore, mimic monocyte/macrophage-mediated lysis. Suppression of monocyte/macrophage cytotoxicity in later stages of HIV-1 infection (AIDS-related complex, AIDS) could partly be reverted by treatment with the cyclooxygenase blocker, indomethacin. The responsible arachidonic acid product mediating suppression was found to be prostaglandin E2, suggesting that in addition to the direct viral interference cellular dysfunction is at least in part a result of altered cytokine regulation.

Adult↗
PubMed1990

Influence of pregnancy on human immunodeficiency virus disease.

Over a period of 3 years (mean 16, extremes 3 and 36 months), we compared clinical and laboratory parameters of 128 female, human immunodeficiency virus (HIV)-infected patients, all in clinical stage II or III (CDC classification). 34 patients were pregnant and delivered a viable infant after at least 28 weeks of amenorrhea (group I), 29 patients were pregnant and had a spontaneous or induced abortion during the first or second trimester (group II), and 64 were non-pregnant female control patients (group III). The changes in the clinical stages over time were not statistically significant between the groups. The only laboratory parameters that were significantly higher in group I at the time of the delivery were: leucocyte count (p less than 0.001), lymphocyte count (p less than 0.05), and sedimentation rate (p less than 0.001). These changes are known to be related to pregnancy and not to HIV disease. All other laboratory parameters showed no significant differences within and between the groups. We conclude, that pregnancy--carried to term or interrupted--does not aggravate the natural evolution of HIV infection in clinical stage II and III patients.

Adolescent↗
PubMed1992

AIDS and multiple sclerosis: neural and mental features.

The presence of mental disorder and cognitive functioning were examined in groups of 20 multiple sclerosis (MS) and homosexual acquired immunodeficiency syndrome (AIDS) ambulatory male outpatients matched for disability and demographic features. Patients who were somatically ill, had past central nervous system infection or tumours or abused intravenous drugs or alcohol were excluded. The groups significantly differed in mental symptoms and mental disorders (DSM-III classification) seen currently and after the diagnosis of MS or human immunodeficiency virus-1 infection. AIDS patients had pre-existing anxiety disorders that affected their current mental symptoms. MS patients showed more evidence of cognitive impairment than equally disabled AIDS patients. The differing neural and mental features are discussed in relation to the current concepts of subcortical and cortical disorders.

AIDS Dementia Complex↗
PubMed2000

Early gastric post-transplantation lymphoproliferative disorder and H pylori detection after kidney transplantation: a case report and review of the literature.

The incidence of post-transplantation lymphoproliferative disorder (PTLD) in the adult renal transplant population ranges from 0.7% to 4%. The majority of cases involve a single site and arise, on average, seven months after transplantation. Histopathology usually reveals B-cell proliferative disease and has been standardized into its own classification. Treatment modalities consist of decreased immunosuppression, eradication of Epstein-Barr virus, surgical resection, systemic chemotherapy and monoclonal antibody therapy; however, mortality remains high, typically with a short survival time. In patients who have undergone renal transplantation, approximately 10% of those with PTLDs present with gastrointestinal symptomatology and disease. Reported sites include the stomach, and small and large bowel. Very few cases of Helicobacter pylori or mucosal-associated lymphoid tissue have been described in association with PTLD. In the era of cyclosporine immunosuppression, the incidence of PTLD affecting the gastrointestinal tract may be increasing in comparison with the incidence seen with the use of older immunosuppression regimens. A case of antral PTLD and H pylori infection occurring three months after renal transplantation is presented, and the natural history and management of gastric PTLD are reviewed.

Helicobacter Infections↗
PubMed1988

Mycoplasma viruses.

Unlike bacterial viruses that infect cells bounded by a cell wall, mycoplasma viruses have evolved to enter and propagate in mycoplasma cells bounded only by a single lipid-protein cell membrane. In addition, mycoplasmas have the smallest amount of genetic information of any known cells, so their complexity is constrained by a limited genetic coding capacity. As a consequence of these host cell differences, mycoplasma viruses have been found to have a variety of structures and replication strategies which are different from those of the bacterial viruses. This article is a critical review of mycoplasma viruses infecting the genera Acholeplasma, Spiroplasma, and Mycoplasma; included are data on classification, morphology and structure, biological and physical properties, chemical composition, and productive and lysogenic replication cycles.

Acholeplasma↗
PubMedDate not supplied

[An etiopathogenic and therapeutic update in chronic viral hepatitis in children].

The author presents the new prospects in the treatment of the chronic viral hepatitis in children, which is an up-to-date-problem in the last decade. There are emphasized the present aspects concerning the etiopathogenesis of the disease, which represent a constellation of achievements as a scientific foundation for the therapy: new notions about the viral genome, the mutant viruses, the host's cell-mediated immunity. There are reminded the classifications of the chronic hepatitis and especially the new one of the chronic type B hepatitis, the carries state risks, the vertical transmission from mother to child as an epidemiological source, valid in our country, too. There are specified the findings of the inefficiency and the contraindication of the cortisone and immunosuppressive therapy in patients with proved viral markers (the improvement of the HBV replication and thus, worsening the disease). The present and the future therapy is represented by the antiviral and immunomodulator drugs (alfa-IFN); there are presented the doses, the mode of administration, the predictive and responsivity factors, as well as the combined therapy (prednisone and antivirals). There is concluded that the passive and active immunoprophylaxis in the newborns of HBs Ag-positive mothers in the replicative phase is a great necessity.

Adjuvants, Immunologic↗
PubMed1992

[Lymphocytic alveolitis in the early stages of HIV infection: correlation with biological and prognostic factors].

Broncho-alveolar lavage was performed to assess the degree of pulmonary lymphocytic alveolitis in 32 asymptomatic patients who were infected with the Human Immunodeficiency Virus (VIH). The patients were stages II and III of the CDC classification and the aim of the study was to determine the frequency, nature and prognostic role of the findings. 62.5% of the subjects (20/32) presented with a lymphocytic alveolitis which consisted predominantly of CD8 lymphocyte (64.3 +/- 3.5%), in the absence of an opportunistic infection or broncho-pulmonary tumours. Two sub-populations of alveolar CD8 were shown at comparable levels, a) sub-population CD8+D44+ (22.1 +/- 5%), in whom we showed the possession of cytotoxic activity in particular specific for VIH; b) sub-population CD8+CD57+ (19.6 +/- 3%) which we have shown to be capable in vitro of inhibiting the effector phase of cytotoxic activity of CD8+D44+ alveolar cells specific for VIH. In this group of 32 patients the occurrence of an alveolitis was not correlated with the usual prognostic factors of infection by VIH measured simultaneously with broncho-alveolar lavage (the level of CD4+ blood lymphocytes, and the beta 2-plasma microglobulins and the presence of p24 antigenaemia). In addition the level of CD4 lymphocytes supperior to 400/mm3 and of beta 2-microglobulins less then 3 mg/l whether a lymphocytic alveolitis was there or not confirmed the relatively poorly developed state of the VIH infection in these asymptomatic patients. Also the occurrence of a lymphocytic alveolitis did not seem to be linked to progression of the disease in the group of patients studied.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

AIDS--public knowledge in Norway 1986.

This paper studied different kinds of knowledge related to HIV/AIDS in the adult Norwegian population. The empirical basis stems from two national interview surveys conducted in 1986. Data were analysed using contingency table analysis and multiple classification analysis (MCA). Totally, 64% knew that HIV/AIDS is caused by a virus. Homosexuals, drug-users, prostitutes and bisexuals were mentioned most often as groups at high risk of becoming infected. As to knowledge about the transmission of the infection, 95% were aware that sex between men and blood transfusion may be channels of infection, 93% recognized contaminated needles, and 85% sexual contact with a person of the opposite sex as possible routes of transmission. A substantial number of respondents were uncertain whether the infection can be transmitted through social contact. Knowledge about HIV/AIDS increased with diminishing age and with increased level of income and education. The direct effect of age upon knowledge may be explained by the theory of selective exposure, which predicts that the seeking of information is influenced by personal needs and interests. The social gradient of knowledge about HIV/AIDS reflects the general flow of information in a social system, and differences in the use of the media by the different social subgroups. Finally, the paper underlines the importance of filling the gaps in the public knowledge about how HIV/AIDS is not transmitted, in order to prevent unfounded fear, stigmatisation and discrimination.

Acquired Immunodeficiency Syndrome↗
PubMed1984

Immunohistochemical study of nasopharyngeal carcinoma using monoclonal keratin antibodies.

Nasopharyngeal carcinoma (NPC) provides a unique opportunity to evaluate distinctive epidemiologic features and a possible etiologic relationship with Epstein-Barr virus (EBV) in human malignancy. The lack of a uniformly accepted pathologic classification for NPC has limited the application of this data, although the World Health Organization (WHO) developed a classification that may solve this problem. Monoclonal keratin antibodies were used for staining of NPC for evaluation of its assistance in diagnosis and classification. In the present immunohistochemical study, monoclonal keratin antibodies, designated AE1, AE2, and AE3, and a polyclonal keratin antibody (RAK) were used for study of the presence of keratin in 121 cases of NPC obtained from China and the United States. AE1 monoclonal antibody, which recognizes keratin protein classes 56.5K, 50K, and 40K, was shown to be the most sensitive and specific for NPC tumor cells among the keratin antibodies studied. In addition, some different keratin expression patterns could be identified between different kinds of epithelium and different tumor groups, with possible relevance to the histogenesis of the histologic subtypes of NPC.

Antibodies, Monoclonal↗