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PubMed1999

Detection of field isolates of human and animal group C rotavirus by reverse transcription-polymerase chain reaction and digoxigenin-labeled oligonucleotide probes.

Rotaviruses (RV) are important etiological agents of acute gastroenteritis in infants and young children, as well as the young of a variety of animals worldwide. These viruses belong to Reoviridae family and contain a genome of 11 segments of double-stranded RNA (dsRNA). Two major proteins, VP4 and VP7, encoded by genome segments 4 and 7, 8 or 9, respectively, evoke a neutralizing antibody response and form the basis for the current classification of group (gp) A rotavirus into P (VP4) and G (VP7) serotypes. Although much recent progress has been made on the molecular biology of gp C RV, routine methods to detect and discriminate human, porcine, and bovine strains are not available widely. In this study, a multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) and digoxigenin-labeled (dig) oligonucleotide probes using chemiluminescence has been developed to detect and discriminate VP7 genes from culture-adapted and field isolates of human, porcine and bovine gp C RV. The multiplex RT-PCR and dig-probes were specific for the VP7 genes of human, porcine and bovine gp C RV and allowed detection and characterization of single and mixed infections of porcine gp C RV with porcine gp A or gp B rotaviruses. Detection rates for gp C RV were more than 50% when compared with polyacrylamide gel electrophoresis. These new diagnostic assays may help determine the epidemiological importance of these viruses in human and animal infections.

Animals↗
PubMed2000

Malignant lymphoma in southern Taiwan according to the revised European-American classification of lymphoid neoplasms.

BACKGROUND: The purpose of the current study was to determine the distribution and relative frequency of each subtype of malignant lymphoma in southern Taiwan according to the revised European-American classification of lymphoid neoplasms (REAL). METHODS: The pathology files of a regional hospital in southern Taiwan for 1989-1998 were searched for malignant lymphoma, lymphoproliferative disorder, and Hodgkin disease (HD). The results of light microscopy, immunohistochemistry, and in situ hybridization for Epstein-Barr virus-encoded RNA (EBER) were correlated with clinical findings, and all cases were classified according to REAL. RESULTS: A total of 205 cases were analyzed retrospectively. There were 197 cases (96.1%) of non-Hodgkin lymphoma (NHL) and 8 cases (3. 9%) of HD. Among the 197 NHL cases, 161 (81.7%) were of B-cell lineage and 36 (18.3%) were of T-/natural killer cell lineage. Diffuse large B-cell lymphoma, extranodal marginal zone lymphoma, and follicular lymphoma were the most common B-cell subtypes and represented 47.2%, 19.3%, and 6.1%, respectively, of all NHL cases. Among the 36 cases of T-/natural killer cell lineage, unspecified peripheral T-cell lymphoma (8.6%), T-/natural killer cell lymphoma (angiocentric lymphoma) (4.1%), and anaplastic large cell lymphoma (3.6%) were the most common subtypes. Seven of eight T-/natural killer cell lymphoma cases were positive for EBER. The eight cases of HD were classified as lymphocyte-rich classic (two cases), nodular sclerosis (two cases), and mixed cellularity (four cases) subtypes. Three of these eight cases were positive for EBER. CONCLUSIONS: To the authors' knowledge this study is the first in Taiwan using the REAL classification and it again confirms the different geographic distribution of the various subtypes of malignant lymphoma. The frequency of T-/natural killer cell lineage NHL in Taiwan is higher than that in Western countries but not as high as reported previously.

Geography↗
PubMedDate not supplied

Typing of field rabies virus strains in FR Yugoslavia by limited sequence analysis and monoclonal antibodies.

A total of 32 rabies virus isolates (15 of fox, 14 of cat and 3 of dog origin) from the territory of FR Yugoslavia were collected from December 1996 till February 1998 and analyzed by limited sequencing of N gene and by indirect immunofluorescence and a panel of 20 antinucleocapsid monoclonal antibodies (MAbs). All examined strains were characterized as sylvatic fox strains. Two main genetic variants were detected, 15 isolates belonging to Group I, 14 belonging to Group II, while the remaining 3 could not be classified into any group. This classification was confirmed by MAbs. The obtained results indicate at least two independent cycles of rabies transmission, probably resulting from multiple modes of transmission to the territories now belonging to FR Yugoslavia.

Animals↗
PubMed1998

Encephalopathy and progression of human immunodeficiency virus disease in a cohort of children with perinatally acquired human immunodeficiency virus infection. Women and Infants Transmission Study Group.

OBJECTIVE: To describe the incidence, predictors, and survival of children with human immunodeficiency virus (HIV) encephalopathy followed in the Women and Infants Transmission Study cohort. STUDY DESIGN: Retrospective review of clinical and immunologic staging of perinatally HIV-infected infants, based on the 1994 Centers for Disease Control and Prevention Classification System. RESULTS: Data were available for 128 HIV-infected children, with a median follow-up of 24 months. HIV encephalopathy was diagnosed in 27 (21%) of children. Median survival after diagnosis was 14 months. Of children with encephalopathy, 74% had at least moderate immunosuppression by the time of diagnosis. Encephalopathy represented the first acquired immunodeficiency syndrome-defining condition in 67%, and the only one in 26% of children. Hepatosplenomegaly or lymphadenopathy during the first 3 months of life was diagnosed in 63%, in contrast to 29% of those without encephalopathy (p value = 0.001). Cardiomyopathy was present in 30% of the children with encephalopathy versus 2% of those without encephalopathy. High viral load in infancy was associated with increased risk of encephalopathy but was not predictive of age at onset. CONCLUSIONS: Encephalopathy in children with HIV is common and is associated with high viral load, immunodeficiency, and shortened survival. Encephalopathy was more likely to develop in infants with early signs and symptoms of HIV, although age at onset could not be predicted.

AIDS Dementia Complex↗
PubMed1988

Ocular herpes simplex infection: pathogenesis and current therapy.

Ocular herpes simplex disease has a variable pattern of manifestations and recurrences as a result of the site and extent of the infection, the host immunologic events, the trophic damage within ocular tissues, and the toxic effects of antiviral medications. Laboratory research has established a clinical model and a working hypothesis about the complex pathophysiologic features of the disease and the interaction of the virus with its host tissue. Recent studies have further defined the viral genome and its role in virulence and pathogenicity. Antiviral therapy is effective in some but not all aspects of the ocular infection. A proposed clinical classification of ocular herpes simplex is based on the manifestations associated with viral disease and those associated with the host response and the subsequent structural damage. A plan for medical and surgical management of ocular herpes simplex, based on current knowledge of the disease process, relates to the integrity of the epithelium and the presence of active viral disease.

Humans↗
PubMed2003

Primary lymphoma of the liver: clinical-pathological features and relationship with HCV infection in French patients.

Primary lymphoma of the liver (PLL) is rare. In some cases, the hepatic lymphoma has been diagnosed in patients who were infected by the hepatitis C virus (HCV). It has been suggested that HCV plays a role in the pathogenesis of lymphoma. The aim of our multicentric retrospective study was to assess the characteristics of PLL and to determine the prevalence of HCV infection in PLL. Thirty-one immunocompetent patients (anti-human immunodeficiency virus, anti-human T-cell leukemia/lymphoma virus negative, no history of allograft) with PLL fulfilled the entire selection criteria. The liver biopsy specimens were reassessed by the same pathologist. The non-Hodgkin's lymphomas were classified according to the World Health Organization classification. Blood samples were tested in 28 patients for antibodies to HCV, and HCV RNA was detected by reverse transcription polymerase chain reaction. In the majority of cases, the clinical, biologic, and radiologic data were nonspecific. Twenty-seven of 31 patients presented a B-cell lymphoma corresponding to the centroblastic morphologic variant of a diffuse, large B-cell lymphoma (22 cases), a Burkitt's lymphoma (1 case), an extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue type (3 cases), and unclassified, small B-cell lymphoma (1 case). The 4 other cases were T-cell lymphomas. The prevalence of HCV infection was 21% (6 of 28 cases). All of these patients were positive for HCV RNA by polymerase chain reaction in blood. Most of the HCV-infected patients presented a high-grade, B-cell type lymphoma. In conclusion, our study confirms the rarity of PLL and demonstrates an increased prevalence of HCV infection.

Adult↗
PubMed1994

Glycoforms of alpha 1-acid glycoprotein in sera of human immunodeficiency virus-infected persons.

In acute infections thus far studied, there is a relative increase in plasma protein glycoforms rich in biantennary complex type N-glycans (type I), while in some diseases with chronic inflammatory changes, there is increase in glycoforms with more branched N-glycans (type II). In sera of 109 human immunodeficiency virus (HIV)-infected persons, 38 rheumatoid arthritis patients, and 44 healthy subjects, the composition of alpha 1-acid glycoprotein (AGP) glycoforms was studied using crossed immunoaffinity electrophoresis with concanavalin A as a ligand. In patients in CDC classifications I, II, and III, distribution of AGP glycoforms was analogous to that in normal subjects. Type I alterations were observed in patients in group IV who had no signs of arthritis. Type II changes, analogous to those found in rheumatoid arthritis, were seen in group IV patients who developed arthritis. Most significant type I changes were associated with Pneumocystis carinii pneumonia (specificity, 100%; sensitivity, 96%).

Arthritis↗
PubMed1992

[Perinatal transmission of AIDS. Experience at the National Institute of Perinatology].

From January 1989 to February 1992, 19 pregnant women infected with human immunodeficiency virus (HIV) were attended at the Instituto Nacional de Perinatologia in Mexico City, all of them at the end of pregnancy as well as 15 of their offspring. Sexual transmission was found in 15 patients; the initial classification of 16 was CDC II, only one case with AIDS, and during pregnancy 2 cases changed their clinical status. Absolute CD4 count in 2 cases was lower 20%, None of 10 had positive VDRL and one case showed a positive PPD. All neonates were at term and eutrophics. During their first 3 months of life, 2 had an infectious disease and died. The serologic follow-up at the moment reports 3 having HIV infection (20%), 3 no HIV infection and 9 in study are sero-positive.

Acquired Immunodeficiency Syndrome↗
PubMed1985

[Is chronic persistent hepatitis decidedly benign?].

Issuing from an analysis of the subjective and objective findings as well as of social data of 77 patients with histologically ascertained chronic persisting hepatitis after virus hepatitis non-A/non-B the problem is pursued whether or not - as in literature is nearly homogeneously assumed - the chronic persisting hepatitis is a decidedly benign disease. Apart from the difficulties in the clear histological classification mentioned by other authors it seemed to be profitable to demonstrate in detail the impairments by persisting symptoms which are to be established in the 5th year of the disease (75% of the patients), by acute attacks (ALAT max. 6.9 mymol/1 . s) with corresponding disabilities (40% of the patients) and the effects on social and professional life. The chronic persisting hepatitis is a very heterogeneous group, which must be considered more differentiated concerning the value of the disease and the prognosis. In this case the etiology must apparently more be taken into consideration, for the findings demonstrated in the 5th year of the disease of the chronic persisting hepatitis (non-A/non-B) show only partly (quoad vitam) a benign prognosis.

Adult↗
PubMed1994

Anticardiolipin antibodies in pediatric patients with human immunodeficiency virus.

OBJECTIVE: To study the presence of IgG and IgM anticardiolipin antibodies (aCL) in children with human immunodeficiency virus (HIV) infection and to determine their prevalence and clinical significance. METHODS: We studied 34 children with HIV infection: 26 patients were classified P-2, and 8 were P-1 according to the Centers for Disease Control classification. HIV transmission was from mother to child in 33 cases. aCL were measured by ELISA: RESULTS: IgG aCL were found in 28 (82%) and IgM aCL in 7 (20%). No difference in frequency and levels was found between class P-2 (85%, mean 54.5 PL units) and class P-1 (75%, mean 50.3 PL units). aCL were not related to the duration of the infection, clinical stage of disease, or with events like opportunistic infections. Children from sexually infected or intravenous drug user mothers showed no differences. CONCLUSION: As in adults, aCL are commonly found in children with HIV infection. The significance of this finding is still unclear.

Antibodies, Anticardiolipin↗
PubMed1998

Human papilloma virus in verrucus carcinoma of the vulva: an immunopathological study of three cases.

The pathological features of three cases of verrucus carcinoma of the vulva, examined in our laboratory during the last decade are presented. Verrucus carcinoma of the vulva is of special interest because of its rarity (6.5% of our cases of malignant lesions of the vulva), its special morphology and the problems in differential diagnosis that are encountered. There is also evidence that there is an association with HPV infection. We present the pathological features of three cases of verrucus carcinoma that we studied in the last decade in our Laboratory among 48 malignant lesions of the vulva. An immunohistochemical detection of HPV was performed by the streptavidine-viotine method and classification by in situ hybridization showed the presence of HPV 6/11 in all cases.

Aged↗
PubMed1984

Poliomyelitis in the USA: virtual elimination of disease caused by wild virus.

The average number of paralytic poliomyelitis cases per year in the United States has fallen from 16 000 just before vaccine was introduced in the 1950s to only 12 in 1978-83. 18 of the 69 cases (26%) reported in this 6-year period were not vaccine associated according to the epidemiological classification of paralytic poliomyelitis cases, established in 1975. The van Wezel antigenic differentiation test and oligonucleotide fingerprinting provide a laboratory basis for definitive characterisation of wild and vaccine-like poliovirus strains. Of the 69 cases, isolates from 42 have been analysed; 31 were vaccine-like poliovirus and 11 wild poliovirus. 7 of the wild poliovirus isolates are from cases in a 1979 outbreak caused by poliovirus imported from the Netherlands through Canada; 1 is from a single importation; and 3 are from isolated cases with no identified source. No indigenous wild strain has been isolated from any reported poliomyelitis case since 1981, when a wild strain was isolated from an immunodeficient individual.

Humans↗
PubMed1991

Histopathologic features of high-grade non-Hodgkin's lymphomas in acquired immunodeficiency syndrome. The French Study Group of Pathology for Human Immunodeficiency Virus-Associated Tumors.

High-grade B-cell non-Hodgkin's lymphomas are observed in 5% to 10% of patients with acquired immunodeficiency syndrome. To describe their histologic subtypes, a group of pathologists was formed. One hundred thirteen cases were reviewed and classified according to the Working Formulation, the updated Kiel classification, and a recent description of morphologic variants of high-grade B-cell non-Hodgkin's lymphoma. Three major types of intermediate- or high-grade lymphomas were observed: (1) large-cell or centroblastic mainly polymorphic lymphomas with a component of immunoblasts (35 cases); (2) immunoblastic lymphomas with plasmablastic and plasmacytic features in most cases (33 cases); and (3) small non-cleaved cell Burkitt's or non-Burkitt's lymphoma (41 cases), with 15 cases fitting typical criteria of Burkitt's lymphoma and 26 heterogeneous cases in which the size and shape of the cells and the presence of plasmablastic features varied. The most frequent pathologic sites of involvement at presentation were the lymph nodes, gastrointestinal tract, bone marrow, brain, oral cavity, and muscles. A comparison between the histologic type and the site of involvement showed that most cases involving lymph nodes, bone marrow, or muscles were small noncleaved cell Burkitt's or non-Burkitt's lymphomas, while those that affected the gastrointestinal tract, brain, and oral cavity were centroblastic or immunoblastic lymphomas with consistent plasmacytic differentiation. In 10 cases, previous persistent generalized lymphadenopathy syndrome was present. In 13 cases, the lymphomatous proliferation was associated with follicular or diffuse hyperplasia seen on the same lymph node biopsy specimen or in another lymph node.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Classification of tumor markers.

Since the discovery of the first tumor markers more than a century ago (Bence-Jones proteins), a vast array of molecules have been described as being associated with cancer. These are generally naturally occurring biomolecules with the exception of neo-antigens expressed in certain tumors induced by viruses. Tumor markers can be broadly classified into tumor specific antigens and tumor-associated markers. Most tumor markers were often heralded as highly tumor specific but subsequent studies demonstrated their presence in normal tissues of the adult or in various stages of ontogeny. As a result, very few tumor-specific antigens can be recognized. The idiotypes of immunoglobulins of B cell tumors and certain neo-antigens of virus induced tumors are two examples that are strictly tumor specific. The vast majority of tumor markers are in reality tumor-associated antigens and can be classified into two types based on their size. The low-molecular weight tumor markers (approximately < 1000 Daltons) include some nucleosides, lipid associated sialic acid, polyamines, pseudouridine, pigment derivatives, and other metabolites. The macromolecular tumor antigens are the most important sub-type useful in the clinical management of cancer patients. The large cancer antigens are either enzymes, growth factors, hormones, receptors, biological response modifiers, oncogenes and their products, or glycoconjugates which include glycoproteins and glycolipids. Collectively all the commercial tumor marker assays available to the oncologist for cancer patient management amount to an annual sales of > $1 billion world wide. The demonstrated clinical usefulness and commercial success of tumor markers have continued to fuel exciting research into the discovery and novel uses of new analytes.

Biomarkers, Tumor↗
PubMedDate not supplied

[Hepatocellular carcinoma].

Hepatocellular carcinoma (HCC), one of the most frequent tumors in the world, is included by the World Health Organization as a relevant public health problem in areas of high incidence as Africa and Southeast of Asia. In this review it will be discussed: a) the close relationship between HCC and hepatitis B virus (HBV), the more universal but not the single etiologic factor having other carcinogens and co-carcinogens involved with the origen of the tumor; b) the great variation in geographic distribution of this tumor, including that of Brazil where the incidence of HCC, including the new macroscopic classification according to the pattern of growth and general with liver cirrhosis in all countries where the tumor is diagnosed; d) some morphological aspects of HCC, including the new macroscopic classification according to the pattern of growth and general characteristics of small HCC; e) the clinical and biochemical aspects, calling attention to the evaluation of serum levels of alpha-fetoprotein, not always increased in patients with HCC, and the immage processing methods, specially ultrassonography, as methods for early diagnosis of HCC, being relevant in the follow-up of high risk patients (cirrhotics HBsAg (+]. Finally some comments are done about the therapeutic methods and perspectives of reduction in the incidence of the tumor with the use of vaccination against HBV infection.

Adolescent↗