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PubMed1995

Sjögren's syndrome.

The literature published over the past year on Sjögren's syndrome is reviewed, including epidemiology, genetic, environmental, and clinical features. The criteria for the classification of Sjögren's syndrome remain controversial, potentially leading to confusion in clinical practice and in research publications. Dryness of the eyes and mouth can result from either interruption of the neurovascular innervation of the glands or from any infiltrative process that affects the ability of the glands to secrete. Recent studies have demonstrated that sicca symptoms also can result from autonomic neuropathy in patients with diabetes, multiple sclerosis, or systemic lupus erythematosus. It is suggested that the term Sjögren's syndrome be used to describe one subset of patients with sicca symptoms who exhibit particular major histocompatibility complex antigens, the presence of T cell lymphoid infiltrates on glandular biopsy, and specific autoantibodies in their sera. Even using these restrictive criteria for classification, no single environmental factor has been shown as necessary or sufficient for pathogenesis. Recent studies on Epstein-Barr virus have indicated a novel deleted virus in some Chinese Sjögren's syndrome patients. Other patients with sicca symptoms and autoimmune features may have infections with HIV or hepatitis C virus.

Animals↗
PubMed1997

Natural history of advanced hepatocellular carcinoma in Crete. Association with hepatitis C virus.

OBJECTIVE: To investigate the clinical characteristics of advanced hepatocellular carcinoma (HCC) in Crete and to analyse the natural course of the untreated disease. PARTICIPANTS: Seventy-three patients (62 men) were enrolled in a prospective 4-year study. Clinical and virological parameters were recorded. Diagnosis was based on either ultrasound guided liver biopsy or a pathognomonic increase in alpha-fetoprotein plus compatible imaging. METHODS: Statistical analysis was performed using histograms, contingency tables and one-way analyses of variance to analyse the characteristics of the disease. For survival analysis Kaplan-Meier survival curves and Cox's proportional hazards models were constructed. RESULTS: HCC in Crete is a mostly male disease (7:1 male:female ratio) and unlike in mainland Greece, it is mostly a hepatitis C virus (HCV)-related disease (54% HCV positive as opposed to only 13% in mainland Greece). Prognosis was associated with Okuda classification (Okuda stage III patients have a relative risk of dying that is seven to nine times higher than for Okuda stage I), the presence or absence of hepatitis Be antigen (HBeAg) and antibody to hepatitis B core antigen (anti-HBc). By contrast the presence of anti-HCV was not associated with a worse prognosis. A unit increase of albumin concentration was associated with an 11% decrease in the hazard rate. CONCLUSION: In general, Crete, despite the extremely similar population to the rest of Greece, resembles more closely the situation in Spain or Italy rather than mainland Greece.

Aged↗
PubMed2006

Estimating true antimalarial efficacy by heteroduplex tracking assay in patients with complex Plasmodium falciparum infections.

Heteroduplex tracking assays (HTAs) of Plasmodium falciparum merozoite surface protein 1 block-2 were used to assess complexity of infection and treatment efficacy in a trial of three antimalarial treatments in 141 Malawian pregnant women. An elevated complexity of infection (COI) was associated with anemia, parasite burden, and human immunodeficiency virus infection but was not associated with age or gravidity. Comparisons of HTA patterns before and after treatment allowed the classification of 20 of 30 (66%) recurrent episodes as either definite treatment failures or reinfections. An elevated COI was strongly associated with treatment failure (P=0.003). An algorithm was developed to assign a probability of failure for the 10 indeterminate participants, some of whose infections shared a single variant of high prevalence (>10%). By summing these probabilities, treatment efficacy was estimated.

Animals↗
PubMed1997

Immunohistochemistry of minor salivary gland biopsy specimens from patients with Sjögren's syndrome with and without hepatitis C virus infection.

OBJECTIVES: To characterise phenotypically the minor salivary glands of patients with clinical and histological features of Sjögren's syndrome (SS) infected with hepatitis C virus (HCV). PATIENTS AND METHODS: 75 consecutive patients with SS (31 primary SS, 44 secondary SS) diagnosed by preliminary European classification criteria. The presence of anti-HCV antibodies was detected by commercial third generation ELISA and by a second generation immunoblot assay. Presence of HCV genome in serum was determined by polymerase chain reaction analysis. Expression of CD3, CD4, CD8, CD20, HLA-DR, and CD25 molecules in lymphocytic and epithelial cells on minor salivary glands was detected by immunohistochemical assays. Expression of interferon gamma and interleukin 4 cytokines was determined by in situ hybridisation. RESULTS: Six of 31 primary SS (19%) and one of 44 secondary SS (2%) serum samples were positive for anti-HCV by ELISA. Three samples were positive, three indeterminate, and one sample corresponding to a secondary SS patient was negative by immunoblot. The three immunoblot positive serum samples were also HCV-RNA positive by PCR assay. The study of lymphocytic cells in the diffuse infiltrate of minor salivary glands showed a predominance of the CD3 lymphocytic population. A predominance of CD4 over CD8 T cells (ratio 2:1) was observed in HCV and non-HCV infected patients. The analysis of the lymphocytic focus showed that the HCV infected patients had a predominance of CD20 positive cells. Activation molecules (CD-25 and HLA-DR) were expressed in HCV and non-HCV infected patients in lymphocytic and epithelial cells, however epithelial cell expression of CD25 was low in HCV infected patients. As expected, a pronounced Th1 response was observed in the lymphocytic foci of HCV patients. CONCLUSIONS: HCV infected patients may develop an autoimmune sialadenitis, similar to that described in primary SS.

Adult↗
PubMed1991

[Serological diagnosis of viral hepatitis].

The differentiation and classification of different types of viral hepatitis was essentially improved in the laboratory diagnosis by the direct determination of the virus in serum, viral antigens or their antibodies. Especially for the hepatitis B it is possible to recognize the infectivity by the serum marker HBeAg, the prognosis by seroconversion (HBeAg/HBeAb), the epidemiology, and vaccination prophylaxis, respectively. Without doubt, immunological marker have an increasing significance for prophylaxis, diagnosis, and therapy of viral hepatitis.

Diagnosis, Differential↗
PubMed1996

[Hepatocellular carcinoma. General aspects of diagnosis and treatment].

Hepatocellular carcinoma is the most frequent form of primary hepatic cancer and has a high dissemination capacity. About 90% of tumors develop over a pre-existing cirrhosis but they also may occur in a normal liver. It has a higher frequency among males and 80% of tumors have clinical manifestations. It is associated to hepatitis B and C virus infection, alcoholism, cirrhosis of any etiology, consumption of aflatoxin Bl, oriental race and familial history. Patients are staged using classifications proposed by Okuda, Child-Pugh and the performance status test. Alpha feto protein is useful for diagnosis and follow up Abdominal ultrasound, hepatic scintiscan, angiography with lipiodol, CAT scan and nuclear magnetic resonance have a high diagnostic yield. Non surgical therapeutic alternatives include intratumoral alcoholization, chemoembolization and other such as tamoxifen and monoclonal antibodies. Surgical treatment is based on hepatic resection, whose magnitude depends on hepatic function. Hepatic transplantation is a new therapeutic alternative for patients in whom resection is not feasible and have a single small tumor without metastases.

Biomarkers, Tumor↗
PubMed2004

Thrombotic complications in patients infected with HIV in the era of highly active antiretroviral therapy: a case series.

BACKGROUND: Recent reports suggest that patients infected with human immunodeficiency virus (HIV) may have an increased risk of developing thrombosis, but the etiology, risk factors, and clinical course remain largely undefined, with few descriptive case series. METHODS: We identified 30 patients from an HIV outpatient clinic (treatment population, 650 persons) who had had a total of 43 venous or arterial thromboses during 1996-2002. Data pertaining to demographic characteristics, medical history, thrombosis presentation, and clinical outcomes were abstracted from patient medical records. RESULTS: The median patient age at the time of thrombosis was 43 years. Although the presence of persistent antibody to phospholipids was the most common abnormal finding in the laboratory, evaluation of thrombophilia, cases of low levels of proteins C and S and antithrombin III, and elevated levels of factor VIII and homocysteine were also identified. Seventy-seven percent of the patients smoked cigarettes, 57% had dyslipidemia, and 43% had a malignancy (most commonly Kaposi sarcoma). Although the Centers for Disease Control and Prevention (CDC) classification for 16 patients (53%) was C3, most showed evidence of immune reconstitution (median CD4 cell count, 290 cells/ mu L) and control of the virus (median HIV load, 2290 copies/mL). Lower extremity, deep vein thrombosis and pulmonary emboli accounted for 66% of all thrombotic events. The median time to diagnosis of thrombosis was 1 day (range, 3 h to 3 weeks). CONCLUSIONS: Patients in this series were characterized by a relatively young age at the time of thrombosis, a predominance of elevated levels of lipids, a history of malignancy, and an advanced CDC HIV classification but not by a low CD4 cell count or an elevated HIV load.

Adult↗
PubMed1983

Abnormal behavior of cultured fibroblasts from nodule and nonaffected aponeurosis of Dupuytren's disease.

Vimentin-positive, desmin-negative cells were established in culture from the nodule and from apparently normal palmar aponeurosis of a patient with Dupuytren's disease and compared with normal human embryonic and adult fibroblasts or sarcomatous cells. Cells from the nodule display in vitro biological properties that are intermediate between those expressed by normal fibroblasts and sarcoma cells or cells from the nodule transformed with SV40 virus. Thus, they represent an interesting in vitro model of partially transformed human cells. This behavior is not evolutive and justifies the classification of Dupuytren's disease among the benign mesenchymal tumors. The production of high level of plasminogen activator probably explains the local reactive pathology, and could act as a mitogenic stimulus for the proliferation of the nodule itself. Cultures derived from the apparently normal palmar aponeurosis show some but not all the abnormal growth properties of cells from nodules; this may help to explain the onset of local recurrences. Our results suggest that Dupuytren's disease is not strictly local and limited to the nodules, but affects, at least partially, the whole aponeurosis. Dupuytren's nodules could be considered as a model of tumor progression in a benign situation.

Blood↗
PubMed1994

Rapid genetic characterization of HIV type 1 strains from four World Health Organization-sponsored vaccine evaluation sites using a heteroduplex mobility assay. WHO Network for HIV Isolation and Characterization.

To assist in the preparation for the testing of vaccines against human immunodeficiency virus (HIV) we, as part of the World Health Organization Network for HIV Isolation and Characterization (WHO-NHIC), evaluated the genotypic variation of HIV-1 in cohorts from Brazil, Rwanda, Thailand, and Uganda. Here we report the results from a pilot study of 65 HIV-1-infected individuals. In all cases in which viral envelope gene fragments could be amplified by polymerase chain reaction, subtypes could be assigned using a heteroduplex mobility assay (HMA)1 by comparison with HIV-1 strains representing six HIV-1 envelope subtypes. All subtype classifications matched those found by envelope gene sequencing. Phylogenetic relationships were further clarified by heteroduplex formation between samples within each subtype. A relatively homogeneous subtype E virus population predominated over subtype B viruses in the sample set from Thailand. Viruses from the other countries were also limited to one or two subtypes but were more divergent within each subtype. All samples from Rwanda (13/13) and some from Uganda (3/16) were of subtype A; all Brazilian samples were of subtype B, except for one belonging to subtype C; most samples from Uganda (13/16) clustered with the subtype D. Analysis by HMA is therefore applicable for screening of HIV-1 genotypes in countries under consideration for large-scale vaccine trials. It should be generally useful when samples containing at least one variable genetic locus need to be rapidly classified by genotype and/or analyzed for epidemiological clustering.

AIDS Vaccines↗
PubMed2000

Characterization and construction of functional cDNA clones of Pariacoto virus, the first Alphanodavirus isolated outside Australasia.

Pariacoto virus (PaV) was recently isolated in Peru from the Southern armyworm (Spodoptera eridania). PaV particles are isometric, nonenveloped, and about 30 nm in diameter. The virus has a bipartite RNA genome and a single major capsid protein with a molecular mass of 39.0 kDa, features that support its classification as a Nodavirus. As such, PaV is the first Alphanodavirus to have been isolated from outside Australasia. Here we report that PaV replicates in wax moth larvae and that PaV genomic RNAs replicate when transfected into cultured baby hamster kidney cells. The complete nucleotide sequences of both segments of the bipartite RNA genome were determined. The larger genome segment, RNA1, is 3,011 nucleotides long and contains a 973-amino-acid open reading frame (ORF) encoding protein A, the viral contribution to the RNA replicase. During replication, a 414-nucleotide long subgenomic RNA (RNA3) is synthesized which is coterminal with the 3' end of RNA1. RNA3 contains a small ORF which could encode a protein of 90 amino acids similar to the B2 protein of other alphanodaviruses. RNA2 contains 1,311 nucleotides and encodes the 401 amino acids of the capsid protein precursor alpha. The amino acid sequences of the PaV capsid protein and the replicase subunit share 41 and 26% identity with homologous proteins of Flock house virus, the best characterized of the alphanodaviruses. These and other sequence comparisons indicate that PaV is evolutionarily the most distant of the alphanodaviruses described to date, consistent with its novel geographic origin. Although the PaV capsid precursor is cleaved into the two mature capsid proteins beta and gamma, the amino acid sequence at the cleavage site, which is Asn/Ala in all other alphanodaviruses, is Asn/Ser in PaV. To facilitate the investigation of PaV replication in cultured cells, we constructed plasmids that transcribed full-length PaV RNAs with authentic 5' and 3' termini. Transcription of these plasmids in cells recreated the replication of PaV RNA1 and RNA2, synthesis of subgenomic RNA3, and translation of viral proteins A and alpha.

Amino Acid Sequence↗
PubMed1997

Serum selenium versus lymphocyte subsets and markers of disease progression and inflammatory response in human immunodeficiency virus-1 infection.

Serum selenium levels were determined cross-sectionally in 57 HIV-infected patients who were classified according to the Centers for Disease Control (CDC) 1993 classification system. Mean serum selenium levels were lower in CDC stage II (58.7 +/- 12.2 micrograms/L; p < 0.01; n = 18) and stage III (47.6 +/- 11.3 micrograms/L; p < 0.01; n = 19) HIV-infected patients, than in healthy subjects (80.6 +/- 9.6 micrograms/L; n = 48) and stage I patients (73.6 +/- 16.5 micrograms/L; n = 20). Serum selenium levels were positively correlated with CD4 count, CD4/8 ratio, hematocrit, and serum albumin (r = 0.42; r = 0.39; r = 0.48; and r = 0.45; p < 0.01, respectively) and inversely with serum levels of thymidine kinase (r = -0.49; p < 0.01; n = 49) and beta 2-microglobulin (r = -0.46; p < 0.001; n = 49). In addition, serum selenium levels in 20 randomly selected AIDS-free individuals (CDC I: n = 10; CDC II: n = 10) were inversely correlated with serum concentrations of interleukin-8 (IL-8) and soluble tumor necrosis factor receptors (sTNFR) types I and II. There was no correlation with serum immuneglobulin A and total serum protein levels. The results show that the progressive deprivation of serum selenium in HIV-infection is associated with loss of CD(4+)-cells and with increased levels of markers of disease progression and inflammatory response.

Adult↗
PubMed2005

Classification and three-dimensional reconstruction of unevenly distributed or symmetry mismatched features of icosahedral particles.

Methods for the three-dimensional reconstruction of icosahedral particles, such as spherical viruses, from electron micrographs are well established. These methods take advantage of the 60-fold symmetry of the icosahedral group. Several features within these particles, however, may deviate from icosahedral symmetry. Examples include viral genomes, symmetry mismatched vertex proteins, unique DNA packaging vertices, flexible proteins, and proteins that are present at less than 100% occupancy. Such asymmetrically distributed features are smeared in the final density map when icosahedral symmetry is applied. Here, we describe a novel approach to classifying, analysing, and obtaining three-dimensional reconstructions of such features. The approach uses the orientation information derived from the icosahedral orientation search to facilitate multivariate statistical analysis and to limit the orientational degrees of freedom for reconstruction. We demonstrate the application of this approach to images of Kelp fly Virus. In this case, each virion may have two different types of fivefold vertex. We use our approach to produce independent reconstructions of the two types of vertex.

Algorithms↗
PubMed1982

Production and characterization of marmoset lymphoblastoid interferon.

We describe the production of marmoset lymphoblastoid cell interferon (IFN). Optimal yields of IFN were obtained when EBV-transformed lymphoblastoid cell lines (LCL) at a cell density of 1 X 10(6)/ml were incubated with 100 HAU Sendai virus/ml for 24 h. Sendai-virus-induced marmoset lymphoblastoid cell IFN was acid-stable and exerted antiviral activity on both homologous and heterologous human cells, thus allowing its classification as IFN alpha. Marmoset lymphoblastoid cell IFN did not inhibit the growth of herpesvirus-transformed marmoset T-or B-cell lines, but markedly enhanced marmoset NK-cell activity against human myeloid leukemia target cells. The use of lymphoblastoid cell IFN in marmosets in vivo may contribute to an understanding of the pathogenic role of IFN in herpesvirus-induced lymphoproliferative diseases.

Animals↗
PubMed2006

Cytogenetic analysis of B-cell posttransplant lymphoproliferations validates the World Health Organization classification and suggests inclusion of florid follicular hyperplasia as a precursor lesion.

Cytogenetic abnormalities in B-cell posttransplant lymphoproliferative disorders (PTLD) have not been well characterized. We thus performed cytogenetic analysis of 28 cases of B-cell PTLD, 1 infectious mononucleosis (IM)-like lesion, 9 polymorphic PTLD, 17 monomorphic PTLD, and 1 classical Hodgkin lymphoma (HL), and correlated the karyotypic findings with the phenotype, Epstein-Barr virus infection status, and clinical outcome. Karyotypes of 19 cases of posttransplant florid follicular hyperplasia (FFH) were also analyzed. Informative karyotypes were obtained in 20 (71.4%) of 28 PTLDs and 18 (94.7%) of 19 FFHs. Clonal karyotypic abnormalities were detected in 13 (65%) of 20 PTLDs, including 9 (75%) of 12 monomorphic PTLDs, 2 (33.3%) of 6 polymorphic PTLDs, 1 IM-like lesion, and 1 HL, and 2 (11.1%) of 18 FFHs. Recurrent chromosome breaks at 1q11-21 (n = 6, including 1 FFH), 14q32 (n = 3, including 1 FFH), 16p13 (n = 3), 11q23-24 (n = 2), and 8q24 (c-MYC) (n = 2); gains of chromosome 7 (n = 4), X (n = 3), 2 (n = 3), 12 (n = 2); and loss of chromosome 22 (n = 2, including 1 IM-like lesion) were identified. The presence of cytogenetic abnormalities did not correlate with PTLD phenotype, Epstein-Barr virus infection, or clinical outcome. We describe novel karyotypic aberrations in PTLD and report clonal cytogenetic abnormalities in posttransplant FFH and an IM-like lesion for the first time. Our findings provide validation of the current World Health Organization classification of PTLD and also suggest incorporation of FFH as the earliest recognizable precursor of PTLD.

Adolescent↗