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At least 1,207 records · Page 67Linked to original sources
PubMed2002

Frequency of congenital varicella syndrome in a prospective cohort of 347 pregnant women.

OBJECTIVE: To estimate the rate of congenital varicella zoster virus syndrome in neonates born to women developing varicella zoster virus infections during pregnancy. METHODS: Pregnant women with clinical varicella zoster virus infection were enrolled at ten perinatal centers. Maternal and fetal immunoglobulin (Ig) G and IgM by fluorescent antibody confirmed 74.3% of cases. Specialists examined neonates at 0-6 months, 7-18 months, and 19-30 months after delivery to detect abnormalities of their eyes, hearing, and physical and developmental features. A hierarchical set of criteria was used to define congenital varicella syndrome. A jury of four investigators assigned the classification of all findings. RESULTS: In 362 women enrolled from 1993 to 1996, 15 had herpes zoster, and 347 had primary varicella zoster virus infection. Varicella zoster virus affected 140 women (38.7%) in the first trimester, 122 (33.7%) in the second trimester, and 100 (27.6%) in the third trimester. Five twin pairs were included. Only one case (0.4%) of definite congenital varicella syndrome was found, a 3360-g female infant having a left retinal macular lesion with typical skin scars after maternal varicella at 24 weeks. The maternal blood sample at birth was negative for IgG antibodies to toxoplasmosis and cytomegalovirus. Two cases involved fetal death at 20 weeks and fetal hydrops at 17 weeks after maternal varicella at 11 and 5 weeks, respectively. We found no cases of limb hypoplasia, microcephalus, or cataract. CONCLUSION: The frequency of congenital varicella syndrome is very low (0.4%) in a prospectively studied cohort. Eye examinations of exposed infants had a low yield.

Adult↗
PubMed2024

A framework for automated scalable designation of viral pathogen lineages from genomic data.

Pathogen lineage nomenclature systems are a key component of effective communication and collaboration for researchers and public health workers. Since February 2021, the Pango dynamic lineage nomenclature for SARS-CoV-2 has been sustained by crowdsourced lineage proposals as new isolates were sequenced. This approach is vulnerable to time-critical delays as well as regional and personal bias. Here we developed a simple heuristic approach for dividing phylogenetic trees into lineages, including the prioritization of key mutations or genes. Our implementation is efficient on extremely large phylogenetic trees consisting of millions of sequences and produces similar results to existing manually curated lineage designations when applied to SARS-CoV-2 and other viruses including chikungunya virus, Venezuelan equine encephalitis virus complex and Zika virus. This method offers a simple, automated and consistent approach to pathogen nomenclature that can assist researchers in developing and maintaining phylogeny-based classifications in the face of ever-increasing genomic datasets.

Animals↗
PubMed1990

Clonal origin of mammalian hepatitis B virus-related hepatocellular carcinoma.

The clonal origins of 20 multifocal hepatocellular carcinomas (HCCs) in four woodchucks were analyzed by the Southern blot hybridization technique. The woodchucks were divided into two groups according to the morphological classification of multifocal tumors: 1) three woodchucks had multifocal tumors that were widely separated and similar in size, which suggests a multiclonal origin of the tumors; and 2) one woodchuck had ten small multifocal tumors surrounding two large main tumors, which indicated intrahepatic metastasis from an original tumor. Results from the first group demonstrated that the number of integrated woodchuck hepatitis virus (WHV) DNAs differed from tumor to tumor, and none of the bands were the same size. In the second group, eight of the ten small tumors surrounding the two large tumors showed the same pattern of WHV DNA integration. One demonstrated an additional band and also shared the same bands with the other tumors, and one small tumor had a different pattern of integration from the others. It was concluded that the clone dissimilarity demonstrated by hybridization patterns does not necessarily mean that HCCs originate independently from different clones, because genetic changes may occur after or at the time of metastasis.

Animals↗
PubMed2003

Population-based study of non-Hodgkin lymphoma, histology, and medical history among human immunodeficiency virus-negative participants in San Francisco.

A population-based case-control study of non-Hodgkin lymphoma was conducted in the San Francisco Bay Area of California from 1988 to 1995. The study used Working Formulation histologic subtypes of non-Hodgkin lymphoma. Diffuse and immunoblastic large-cell lymphomas and all follicular lymphomas were combined to reflect two Revised European-American Lymphoma (REAL) classifications. Results were obtained from age- and sex-adjusted polytomous multivariable logistic models for 1,304 cases and 2,402 controls who were negative for human immunodeficiency virus. Statistically significant odds ratios for REAL large-cell lymphoma were decreased for receipt of five or more different vaccines (odds ratio (OR) = 0.65), use of calcium channel blockers (OR = 0.35), mononucleosis (OR = 0.55), plant allergies (OR = 0.72), and animal allergies (OR = 0.40). Odds ratios for REAL follicular lymphoma were decreased for use of nonsteroidal antiinflammatory drugs (OR = 0.67), hepatitis (OR = 0.36), and having had three or more bee or wasp stings (OR = 0.79) and were increased for heart disease (OR = 1.5). Similar elevated odds ratios for heart disease and Bacillus Calmette-Guérin vaccine and decreased odds ratios for nonsteroidal antiinflammatory drugs, plant allergies, and three or more bee or wasp stings were found for small lymphocytic lymphoma. These data provide direction for further investigation of immune function and genetic characteristics of subtypes of non-Hodgkin lymphoma in lymphomagenesis and warrant analyses in large pooled data sets.

Case-Control Studies↗
PubMed2006

Extra-oral plasmablastic lymphoma: report of a case and review of literature.

Plasmablastic lymphoma (PBL) of the oral cavity is classified as one subtype of diffuse large B-cell lymphoma that is most commonly seen in patients with human immunodeficiency virus infection. We report a rare case of PBL in the anal canal of a 33-year-old man with human immunodeficiency virus infection. The lymphoma cells were positive for CD138 and weakly positive for CD79a. In addition, these cells were also positive for CD10. The neoplastic cells were positive for Epstein-Barr virus and negative for human herpes virus 8. Review of the English medical literature revealed many more cases of extra-oral PBL. We propose that the term plasmablastic lymphoma of the oral cavity in World Health Organization classification be revised to simply plasmablastic lymphoma, which would include both oral and extra-oral PBLs, and the term to define the primary site of the lymphoma (ie, oral cavity) be dropped from the terminology used in World Health Organization classification.

Adult↗
PubMed2006

Evidence of host-virus co-evolution in tetranucleotide usage patterns of bacteriophages and eukaryotic viruses.

BACKGROUND: Virus taxonomy is based on morphologic characteristics, as there are no widely used non-phenotypic measures for comparison among virus families. We examined whether there is phylogenetic signal in virus nucleotide usage patterns that can be used to determine ancestral relationships. The well-studied model of tail morphology in bacteriophage classification was used for comparison with nucleotide usage patterns. Tetranucleotide usage deviation (TUD) patterns were chosen since they have previously been shown to contain phylogenetic signal similar to that of 16S rRNA. RESULTS: We found that bacteriophages have unique TUD patterns, representing genomic signatures that are relatively conserved among those with similar host range. Analysis of TUD-based phylogeny indicates that host influences are important in bacteriophage evolution, and phylogenies containing both phages and their hosts support their co-evolution. TUD-based phylogeny of eukaryotic viruses indicates that they cluster largely based on nucleic acid type and genome size. Similarities between eukaryotic virus phylogenies based on TUD and gene content substantiate the TUD methodology. CONCLUSION: Differences between phenotypic and TUD analysis may provide clues to virus ancestry not previously inferred. As such, TUD analysis provides a complementary approach to morphology-based systems in analysis of virus evolution.

Algorithms↗
PubMed1995

Comparison of different procedures for serotyping aquatic birnavirus.

The current classification of aquatic birnaviruses is based on seroneutralization assays with polyclonal antibodies. In this study a comparison of several procedures used for serotyping aquatic birnaviruses was made with 10 virus strains (4 reference strains from salmonids and 6 birnaviruses isolated from turbot [Scophthalmus maximus]). The relationships among the birnavirus strains were studied by seroneutralization assay with polyclonal antibodies and by immunodot assay with both polyclonal and monoclonal antibodies. The results were compared with a presumptive classification obtained from analysis of restriction enzyme patterns of cDNA products obtained by PCR amplification. No correlation was found among the results obtained by the different procedures. The seroneutralization and the immunodot assays with polyclonal antibodies were not useful in classifying these birnaviruses strains; however, patterns of reaction with monoclonal antibodies emphasized the individuality of the strains, particularly in the case of two strains (231 and 460) whose patterns did not correspond to established serotypes. The application of PCR and restriction enzyme analysis is a promising system for approaching the classification of this viral group on the basis of genomic differences and similarities. The variable results obtained in this comparison lead us to think that the current classification of aquatic birnavirus may not be the most accurate and there is a need for modification incorporating recent isolates, not only from salmonid species but also from marine fish.

Animals↗
PubMed1985

A classification of HTLV-III infection based on 75 cases seen in a suburban community.

Since 1981, 75 patients have been seen at our hospital with human T-cell lymphotropic virus type III (HTLV-III) infection. We have classified their clinical presentation into Groups 0 to 6. Groups 0 to 3 all have antibody to the Mr 41,000 protein of HTLV-III. Group 0 has no evident disease (9 patients), Group 1 has lymphadenopathy with or without exaggerated infection (16 patients), Group 2 has persistent lymphadenopathy with chronic hepatitis B surface antigenemia or profound hypergammaglobulinemia (7 patients), Group 3 has oral candidiasis with or without lymphadenopathy (7 patients). In Group 4 are acquired immunodeficiency syndrome (AIDS) adults or children (32 patients). Group 5 is a special classification for immunocompromised patients. Group 6 patients have lymphomas and Mr 41,000 protein antibody. Four children were classified separately. Three patients in Group 3 developed Group 4 disorders (AIDS). Four patients in Group 4 developed Group 6 disorders. HTLV-III infection spread in families (8 of 36), all from infected mothers to children. In 17 sexual partners, 6 were found to be infected. Five of 6 infected partners were homosexuals. We saw an inordinate number of transfusional AIDS (4 of 29) and 1 of 46 other disorders. Two infants also presented with severe intracranial defects, one with microcephaly and one with cranial calcifications and lucency. HTLV-III is spreading with alarming speed.

Acquired Immunodeficiency Syndrome↗
PubMed2002

Characterization of neutralization sites on the circulating variant of swine vesicular disease virus (SVDV): a new site is shared by SVDV and the related coxsackie B5 virus.

Using a panel of new monoclonal antibodies (mAbs), five neutralizing, conformation-dependent sites have been identified on the antigenic variant of swine vesicular disease virus (SVDV) circulating currently. In studies on the antigenic conservation of these sites, the four antigenic/genetic groups of SVDV described showed distinguishable patterns, confirming this classification. By sequencing mAb-resistant mutants, the five sites have been mapped precisely and localized on a three-dimensional model of the SVDV capsid. All were found to be orientated, to a different extent, towards the external surface of the capsid. Three of the five sites, located in VP1, VP2 and VP3, correspond to epitopes identified previously in historic isolates as sites 1, 2a and 3b, respectively. Another site, site IV, which maps to position 258 of VP1, corresponds to an epitope reported recently and is described in this study to be specific for isolates of the most recent antigenic group of SVDV. A fifth site is described for the first time and corresponds to the unique neutralizing site that is common to both SVDV and coxsackie B5 virus; it maps to positions 95 and 98 of VP1, but may also include positions nearby that belong to site 1 on the BC-loop of VP1, suggesting the classification of site Ia. These results may have useful diagnostic and epidemiological applications, since mAbs to the new conserved site Ia provide universal reagents for SVDV detection systems, while the specificity of mAbs to site IV make them unique markers for the most recent strains of SVDV.

Animals↗
PubMed1993

Phylogenetic relationships of dengue-2 viruses.

RNA oligonucleotide fingerprinting studies on a large number of virus isolates previously demonstrated considerable genetic variation in isolates of dengue (DEN)-2 serotype. We report the entire envelope (E) glycoprotein gene and deduced amino acid sequences of 16 DEN-2 viruses and the phylogenetic relationships of these, plus 17 additional published DEN E gene sequences. Comparison of DEN-2 E glycoprotein gene sequences revealed base substitutions scattered throughout the entire gene with as much as 22% sequence divergence. Aligned E glycoprotein amino acid sequences revealed the viruses differed by as much as 10%. There appeared to be constraints on the overall structure of the E protein to maintain biological function. Clusters of amino acid substitutions were present in the hydrophobic membrane anchor region at the carboxyl terminal end of the protein. Maximum parsimony analysis of the E gene sequences allowed construction of a phylogram indicating evolutionary relationships of the virus isolates within the DEN-2 serotype. Five genetic subtypes were identified. Phylogenetic relationships of the DEN-2 serotype and other flaviviruses based on E protein sequences reflected traditional antigenic and serologic classifications.

Adult↗
PubMed1994

Liver resection for hepatocellular carcinoma in the elderly.

OBJECTIVE: To estimate the effectiveness of hepatic resection on hepatocellular carcinoma (HCC) in the elderly. DESIGN: Comparison with younger patients. SETTING: A municipal hospital and a large university hospital in Japan. PATIENTS: The study included 39 patients (age > or = 70 years [the elderly group]) and 229 patients (age < 70 years [the younger group]) who underwent hepatic resection from April 1985 to March 1993. The preoperative clinical features (Child's classification, association of cirrhosis and liver functions) were comparable between two groups. The positive rate for hepatitis C virus antibody was higher in the elderly group (88% vs 59%; P = .016). MAIN OUTCOME MEASURES: Morbidity and survival following operation and the pathological features of HCC. RESULTS: The incidence of postoperative hepatic failure was higher in the elderly group (10% vs 2%; P = .018). However, the incidence of operative death in the elderly group (5% vs 1%) as well as the incidence of other postoperative complications and rates of long-term survival (75.9% vs 51.6% at 5 years) and disease-free survival (30.4% vs 31.0% at 5 years) were similar to those in the younger group. The pathological features of HCC were identical between the two groups. CONCLUSION: The outcome of surgical treatment of HCC in the elderly group was satisfactory when compared with that in the younger group.

Age Factors↗
PubMed2005

SELDI-TOF MS profiling of serum for detection of the progression of chronic hepatitis C to hepatocellular carcinoma.

Proteomic profiling of serum is an emerging technique to identify new biomarkers indicative of disease severity and progression. The objective of our study was to assess the use of surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS) to identify multiple serum protein biomarkers for detection of liver disease progression to hepatocellular carcinoma (HCC). A cohort of 170 serum samples obtained from subjects in the United States with no liver disease (n = 39), liver diseases not associated with cirrhosis (n = 36), cirrhosis (n = 38), or HCC (n = 57) were applied to metal affinity protein chips for protein profiling by SELDI-TOF MS. Across the four test groups, 38 differentially expressed proteins were used to generate multiple decision classification trees to distinguish the known disease states. Analysis of a subset of samples with only hepatitis C virus (HCV)-related disease was emphasized. The serum protein profiles of control patients were readily distinguished from each HCV-associated disease state. Two-way comparisons of chronic hepatitis C, HCV cirrhosis, or HCV-HCC versus healthy had a sensitivity/specificity range of 74% to 95%. For distinguishing chronic HCV from HCV-HCC, a sensitivity of 61% and a specificity of 76% were obtained. However, when the values of known serum markers alpha fetoprotein, des-gamma carboxyprothrombin, and GP73 were combined with the SELDI peak values, the sensitivity and specifity improved to 75% and 92%, respectively. In conclusion, SELDI-TOF MS serum profiling is able to distinguish HCC from liver disease before cirrhosis as well as cirrhosis, especially in patients with HCV infection compared with other etiologies.

Adult↗
PubMed1988

Serological response in patients with chronic asymptomatic human immunodeficiency virus infection.

To examine a possible relationship between decreased immune function and serological parameters, such as human immunodeficiency virus (HIV) antigenaemia and the quality and quantity of whole virus antibodies and antibodies against the major core protein p24, we investigated 160 healthy HIV infected individuals (CDC classification II and III). According to the number of T-helper lymphocytes (CD4 cells) these were divided into two groups (CD4 cell counts above or below 500/microliter), which according to the lymphocyte transformation response to pokeweed mitogen (response above or below 20% of control value) were further subdivided into two groups. Both the presence of HIV antigen (p = 0.022) and the absence of p24 antibodies (p = 0.001) correlated to a decreased CD4 cell count. Lack of p24 antibodies was more frequent than was the presence of HIV antigen among persons with decreased CD4 cell count and decreased response to pokeweed mitogen, indicating that absence of p24 antibodies may be an earlier marker of immune dysfunction than the presence of HIV antigen. In persons with p24 antibodies present, a low such titer was associated with a decrease of both immune parameters. Presence of HIV antigen and absence of p24 antibodies thus seems to correlate with the severity of immune dysfunction in healthy HIV infected individuals.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Surgery for pulmonary tuberculosis.

During the period 1990-1994 a total of 578 operations were performed in 502 patients with various forms of tuberculosis. Most of the patients (68%) were men aged 20 to 50 years (70%). Sputum cultures were positive in 55% of the patients. More than half of all patients were chronic smokers, and about 10% were alcoholics or drug addicts. There were no human immunodeficiency virus-infected patients, and none with acquired immunodeficiency syndrome. The most frequent surgical interventions were, according to the classification adopted in Russia, for cavernous or fibrocavernous tuberculosis (196 cases) and tuberculomas (161 cases). The main operative procedures used were pulmonary resection (n = 280) and pneumonectomy or pleuropneumonectomy (n = 80). Diseased intrathoracic lymph nodes were ablated in 62 patients. Thoracoplasty or thoracomyoplasty were performed in 46 cases, thoracostomy in 37, closure of a thoracic wall defect in 27, and reamputation of the main bronchial stump in 6. Postoperative complications arose in 20% of the patients. More than half occurred in the pleural cavity or bronchi and were associated with tuberculous infection. The postoperative hospital case-fatality rate was 2%. The overall clinical efficacy by the time of discharge was 82.7% (95% in tuberculomas). Reactivation of tuberculosis over the first 3 years after discharge occurred in 6.6% of the patients. Most patients with large or multiple caverns, tuberculomas, intrathoracic caseous lymphadenitis, or various complications of pulmonary tuberculosis cannot be cured (or are not amenable to care in principle) by means of antibacterial therapy because of irreversible morphologic changes in the lungs, bronchi, pleura, lymph nodes, or thoracic wall. For this reason, indications for surgical management of pulmonary tuberculosis should be generally expanded. Excessively long antibacterial therapy for tuberculosis is often inadvisable. Although the availability of standardized regimens of antibacterial therapy is strategically essential, each patient must be treated according to an individual plan. In certain cases thoracic surgeons should be enlisted to participate in the development of such plans.

Adult↗
PubMed2004

Jordi Casals-Ariet.

Explore the source record for details and available documents.

Agglutination Tests↗
PubMed1996

Viral safety of blood derivatives: an overview.

The causes of past accidental viral transmissions associated with blood derivatives are reviewed briefly, as are the safety procedures instituted in Europe on the basis of viral validation studies. A comprehensive five-class classification system for delineating viral risk according to source material and comparative viral safety is presented. Newly emerging viruses are briefly discussed in view of the viral safety of blood products.

Biological Products↗
PubMed1997

Systemic lupus erythematosus (SLE) lymphadenopathy presenting with histopathologic features of Castleman' disease: a clinicopathologic study of five cases.

Lymph node enlargement is common in active systemic lupus erythematosus (SLE), a disease characterized by well defined clinical criteria. Although numerous reports have described the characteristic histology of SLE lymphadenopathy to include necrotizing lesions and hematoxylin bodies, no detailed description has examined the histopathologic features that are similar to Castleman's disease (CD) in SLE patients. In this report, we describe the clinicopathologic findings of CD-like peripheral lymphadenopathy, which was identified in five (26%) of 19 SLE patients. These five patients were all female with an age range of 24 to 44 years, and four of them presented with multicentric lymphadenopathy. They also had systemic symptoms and abnormal laboratory findings, indicating active disease, although two patients had not fulfilled the diagnostic criteria of SLE at the initial disease. The size of the enlarged lymph nodes seldom exceeded 2.0 cm in diameter, and biopsies revealed histopathologic features similar to CD, of intermediate type in three patients and hyaline vascular type in two according to the classification of Flendrig [7]. Immunohistochemical studies demonstrated polyclonal plasma cell populations in all five cases. Epstein-Barr virus genomes were detected in the small lymphocytes of two of the three cases examined by in situ hybridization studies. Recently, the histopathologic findings of CD have been associated with a disrupted immune response, and the present data suggest that SLE should be listed as one of the diseases showing the histopathologic features similar to CD.

Adult↗
PubMedDate not supplied

Helicases as antiviral drug targets.

Helicases catalytically unwind duplex DNA or RNA using energy derived from the hydrolysis of nucleoside triphosphates and are attractive drug targets because they are required for viral replication. This review discusses methods for helicase identification, classification and analysis, and presents an overview of helicases that are necessary for the replication of human pathogenic viruses. Newly developed methods to analyze helicases, coupled with recently determined atomic structures, have led to a better understanding of their mechanisms of action. The majority of this research has concentrated on enzymes encoded by the herpes simplex virus (HSV) and the hepatitis C virus (HCV). Helicase inhibitors that target the HSV helicase-primase complex comprised of the UL5, UL8 and UL52 proteins have recently been shown to effectively control HSV infection in animal models. In addition, several groups have reported structures of the HCV NS3 helicase at atomic resolutions, and mechanistic studies have uncovered characteristics that distinguish the HCV helicase from related cellular proteins. These new developments should eventually lead to new antiviral medications.

Animals↗