Proposed re-classification of furoviruses.
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Plant Viruses↗
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Persistently high Epstein-Barr virus (EBV) loads in peripheral blood lymphocytes from patients with chronic active EBV infection.
Chronic active Epstein-Barr virus infection (CAEBV) is a severe illness with unusual EBV activation that persists for years, and its pathogenesis is largely unknown. After the creation of an accurate and reproducible polymerase chain reaction system to quantify EBV DNA, virus loads in peripheral blood lymphocytes (PBL) were determined in 54 children: 15 with CAEBV, 16 with infectious mononucleosis (IM), and 23 healthy children. Children with CAEBV and those with IM had high virus loads. Lower loads were detected in 47% of seropositive healthy donors. There were two distinct differences between children with CAEBV and those with IM: The former had greater viral replication (10(3)-10(7) copies/2.5x10(5) PBL) than those with IM, and viral replication declined in children with IM whereas active replication persisted for years in subjects with CAEBV. Persisting high virus loads are a possible diagnostic criterion for CAEBV. EBV loads may enable classification and prognosis of EBV infections.
Adolescent↗
Probably virus-induced epithelial lesions in preinvasive cervical cancer.
There is an urgent need to approach the evaluation and classification of cervical intraepithelial lesions and their cytopathological correlations as specifically as possible. Preinvasive cancer (differentiated and undifferentiated carcinoma in situ) of the uterine cervix, the most advanced stages of cervical intraepithelial neoplasia, should be clearly defined and described, and the diagnostic and therapeutic management including the follow-up of the patients outlined in detail. The present results, based on a material of 524 cone biopsies, clearly indicate the existence of two different types of probably virus-induced epithelial lesions in the two histopathologic groups of preinvasive cancer of uterine cervix.
Carcinoma in Situ↗
Serological relationships involving potyviral nonstructural proteins.
This report represents a compilation of many of the publications on antigenic properties of potyviral-specified nonstructural proteins. Polyclonal antisera have been prepared for use in characterization of six nonstructural proteins. These include antisera to the cylindrical inclusion proteins of at least 28 potyviruses, to small nuclear inclusion protein (protease) of four potyviruses, to large nuclear inclusion protein (putative replicase) of three viruses, helper component-protease or amorphous inclusion protein of at least four viruses, to the P1 protein (located at the N-terminus of the polyprotein) of one virus, and to the P3 protein (located between helper component protease and cylindrical inclusion protein) of one virus. Monoclonal antibodies also have been prepared to several of these nonstructural proteins. The evidence thus far indicates that cylindrical inclusions of different potyviruses have both conserved and unique epitopes. Nuclear inclusion proteins and amorphous inclusion proteins also may have conserved and unique epitopes. Antigenic relationships of potyviral nonstructural proteins have potential for the identification and classification of potyviruses.
Plant Viruses↗
Epstein-Barr virus-associated gastric carcinoma in southern India: A comparison with a large-scale Japanese series.
Epidemiological and clinicopathological features of Epstein-Barr virus (EBV) associated gastric carcinoma was compared in India and Japan, two countries differing markedly in gastric cancer incidence. Using in situ hybridization assay, the presence of EBV-encoded small RNA (EBER) was examined in 215, and 2,011 gastric cancer cases in Kerala, India, and Japan, respectively. Ten cases (5%), all males, in the Indian series were EBER-positive. This frequency was similar to that in the Japanese series (6.2%). As was the case with Japanese series, the EBV-associated gastric carcinoma in the Indian series was observed most frequently in the middle part of the stomach (1 in antrum, 4 in middle part, 2 in cardia, and 3 unknown), and, histologically, the diffuse type Lauren's classification (8 cases) was more common than the intestinal type (2 cases). Virus subtyping by PCR-RFLP revealed that all of the 10 EBV strains isolated from the EBER-positive Indian cases were subtype A, and wild-type F for Bam HI F region. In Bam HI I region, 8 cases were type C and the remaining 2 cases were type D. In either series, there was no significant difference in the frequency of tumors with p53 overexpression between EBER-positive and -negative cases. However, the proportion of cells with p53 overexpression in EBER-negative tumors was significantly higher than that in EBER-positive tumors regardless of histological type in both series. In conclusion, the frequency and major clinicopathological features of EBV-associated gastric carcinoma in south India were similar to those observed in Japanese series although gastric cancer incidence in these two countries differs markedly.
Adult↗
Otarine herpesvirus-1: a novel gammaherpesvirus associated with urogenital carcinoma in California sea lions (Zalophus californianus).
The incidence of neoplasia in California sea lions (CSLs) is considered to be unusually high. Electron microscopic examination of some of these urogenital tumours revealed the presence of virions with typical herpes-like structure. While current attempts to cultivate this virus have not been successful, molecular studies employing DNA extracted from tumour tissues allowed both the classification of the agent and its identification in tumours and archived tissue samples. Two genome fragments generated using degenerate primers in PCR demonstrated highest identities with other mammalian gammaherpesviruses. Phylogenetic analysis showed that this novel virus, tentatively designated Otarine herpesvirus-1 (OtHV-1), grouped with members of the gammaherpesvirus subfamily and was distinct from PHV-2, a previously described pinniped gammaherpesvirus. An OtHV-1 specific PCR was established and used to investigate the presence of this virus in CSL tissues. PCR of DNA isolated from animals with these tumours, demonstrated that this virus was present in 100% (16/16) of tumours. Furthermore, DNA extracted from archived brain and muscle tissues was also positive in 29% (4/14) and 50% (7/14) of cases examined. This preliminary study provides evidence to support the hypothesis that the presence of this novel gammaherpesvirus is a factor in the development of urogenital carcinoma in CSLs.
Amino Acid Sequence↗
Genome sequence analysis of Tamana bat virus and its relationship with the genus Flavivirus.
Tamana bat virus (TABV, isolated from the bat Pteronotus parnellii) is currently classified as a tentative species in the genus FLAVIVIRUS: We report here the determination and analysis of its complete coding sequence. Low but significant similarity scores between TABV and member-viruses of the genus Flavivirus were identified in the amino acid sequences of the structural, NS3 and NS5 genes. A series of cysteines located in the envelope protein and the most important enzymatic domains of the virus helicase/NTPase, methyltransferase and RNA-dependent RNA polymerase were found to be highly conserved. In the serine-protease domain, the catalytic sites were conserved, but variations in sequence were found in the putative substrate-binding sites, implying possible differences in the protease specificity. In accordance with this finding, the putative cleavage sites of the TABV polyprotein by the virus protease are substantially different from those of flaviviruses. The phylogenetic position of TABV could not be determined precisely, probably due to the extremely significant genetic divergence from other member-viruses of the family FLAVIVIRIDAE: However, analysis based on both genetic distances and maximum-likelihood confirmed that TABV is more closely related to the flaviviruses than to the other genera. These findings have implications for the evolutionary history and taxonomic classification of the family as a whole: (i) the possibility that flaviviruses were derived from viruses infecting mammals rather than from mosquito viruses cannot be excluded; (ii) using the current criteria for the definition of genera in the family Flaviviridae, TABV should be assigned to a new genus.
Amino Acid Sequence↗
ISOLATION AND CHARACTERIZATION OF A NEW HERPES VIRUS.
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Animals↗
Phylogenetic interrelationships among baculoviruses: evolutionary rates and host associations.
The phylogenetic relationship of several baculovirus polyhedrin genes was investigated. Alignments of 18 polyhedrin gene amino acid sequences from which 12 were also available as DNA sequences were constructed based on positional homology and trees were calculated using character state and distance methods. Our results indicate that the Hymenopteran NsSNPV diverged from the Lepidopteran baculovirus before the separation of the NPV from the GV and subsequent radiation of these Lepidopteran groups. Moreover, this analysis indicates that lepidopteran NPV are clustered in at least two groups with distinct evolutionary rates. Group I includes the AcMNPV, BmMNPV, BmSNPV, OpMNPV, AgMNPV, and possibly the GmMNPV and AsMNPV. Group II includes the MbMNPV, PfMNPV, SfMNPV, SeMNPV, and possibly the OpSNPV. This grouping is also supported by a tree constructed from sequence data from the 5' untranslated leader region of the polyhedrin gene. Furthermore, the polyhedrin-based phylogeny was analyzed for its congruence to the genomic organization and other biological characteristics of the baculoviruses. This study shows that the SNPV and MNPV morphotypes have to be taken with caution as classificatory traits since they appear to be unpolarized. In addition, the comparison of the baculovirus phylogeny with the Lepidoptera phylogeny confirms the assumption that the evolutionary history of the baculoviruses is not entirely in agreement with the taxonomic organization of the Lepidoptera, implying that the common designation of baculoviruses based on the hosts may not be adequate for baculovirus classification since it does not reflect the genetic relatedness of the viruses.(ABSTRACT TRUNCATED AT 250 WORDS)
Amino Acid Sequence↗
Basic and clinical immunology.
The authors selected articles published in the literature from January 2004 through December 2004 that were relevant to the areas of basic and clinical immunology. Several articles explored the development of TH1 or TH2 response and the role of the monocyte-T cell interaction. Others were articles describing the action of drugs commonly used in asthma to inhibit cytokine responses and the anti-inflammatory role of nonimmune pulmonary cells present in the lung. Several reports show how dendritic cells are being developed as vehicles for DNA vaccines aimed at stimulating cellular responses, an advance of great importance for HIV researchers working on vaccines, who are concerned about the different ways HIV evades the immune response. Other publications described Toll-like receptors in diverse cells, including mast cells and CD4+ T cells, for the recognition of viruses and bacteria. In the area of clinical immunology, an updated classification for primary immunodeficiencies with more than 100 identified genes responsible for these diseases and the report on the second clinical trial of gene therapy for X-linked severe combined immunodeficiency syndrome were published. Significant advances included the clinical prognosis in common variable immunodeficiency for patients presenting with lung pathology, the safety of live vaccines in partial DiGeorge syndrome, the report of patients with complete DiGeorge syndrome with the presence of peripheral blood T cells, the clinical spectrum of patients with NF-kappaB essential modifier (NEMO) gene deficiency, the publication of a consensus algorithm for the management of hereditary angioedema, and the report of immune restoration syndrome in pediatric HIV infection.
Animals↗
The expression of MAGE and GAGE genes in uterine cervical carcinoma of Korea by RT-PCR with common primers.
BACKGROUND: Melanoma antigen genes (MAGE) and GAGE genes are encoded by genes that are silent in virtually all normal adult tissues but are expressed in tumors from various tissues. These gene products are targets for specific immunotherapy as they are presented by HLA I molecules and recognized by autologous cytotoxic T-lymphocytes. However, the characteristics of these genes, especially in uterine cervical cancer are relatively unknown. PURPOSE: This study evaluated the prevalence of MAGE and GAGE by reverse transcription-polymerase chain reaction (RT-PCR) with common primers and discusses clinical implications in cervical carcinoma. MATERIALS AND METHODS: Fresh tissue from 37 cases of primary squamous cell carcinoma and normal cervical mucosa were evaluated for clinicopathologic parameters including Human Papilloma Virus (HPV)-16,18 infection by PCR, tumor stage by FIGO classification and lymph node involvement. RT-nested PCR for the MAGE and GAGE genes was performed with common primers and DNA sequencing after subcloning was used for identification of PCR products of MAGE. Formalin-fixed paraffin embedded material from the same specimen was analyzed by in situ RT-PCR for MAGE. RESULTS: Expression of MAGE and GAGE was not observed in normal tissues. Eleven out of 37 cases expressed MAGE mRNA (29.7%): analysis of subtypes identified one case of MAGE-1, two cases of MAGE-4b, six cases of MAGE-3, and two unknown subtypes. Thirteen out of 37 cases (35.1%) expressed GAGE mRNA. No significant relationships between expression of these genes and FIGO staging, lymph node metastasis or HPV infection were found. CONCLUSION: Expression of MAGE and GAGE may be involved in the development of uterine cervical carcinoma from intraepithelial neoplasia, although without distinct prognostic significance. MAGE and GAGE genes have the potential to be used as targets for the treatment of uterine cervical carcinoma.
Antigens, Neoplasm↗
Early changes of body composition in human immunodeficiency virus-infected patients: tetrapolar body impedance analysis indicates significant malnutrition.
Total body water, body fat, body cell mass (BCM), extracellular mass (ECM), and the ECM-BCM ratio by impedance analysis were determined in 193 human immunodeficiency virus (HIV)-infected patients and 340 control subjects. Walter Reed (WR) classification was WR 2 in 26, WR 3-5 in 85, and WR 6 in 82 patients. Whereas resistance was increased, reactance and the phase angle were significantly reduced in all patient groups. Neither body weight nor body mass index (BMI) was affected in WR 2 patients, but BCM was reduced (31.9 +/- 4.3 vs 35.8 +/- 7.3 kg, P < 0.007) and ECM (31.2 +/- 4.4 vs 28.8 +/- 3.8 kg) as well as ECM-BCM ratio increased (0.99 +/- 0.14 vs 0.83 +/- 0.16, P < 0.001). In contrast to WR classification, diarrhea did not correspond with malnutrition. A loss of BCM (malnutrition) occurred already in otherwise symptomless HIV-infected patients (WR 2). This effect can be measured by tetrapolar impedence analysis but not by body weight or BMI.
Adult↗
Genetic heterogeneity among parapoxviruses isolated from sheep, cattle and Japanese serows (Capricornis crispus).
Standard strains of four parapoxviruses and seven unclassified Japanese strains isolated from sheep, cattle and wild Japanese serows (Capricornis crispus) were compared molecularly. Restriction fragment length polymorphism (RFLP) analysis of viral DNA, indirect immunofluorescence assays using monoclonal antibodies, partial nucleotide sequencing of the envelope gene, phylogenetic analysis and PCR-RFLP were carried out. These analyses revealed that the parapoxviruses were divided into four groups and the region sequenced in this study was highly conserved within each group. Each of the Japanese isolates was classified into one of these groups. These findings also indicated that parapoxvirus infections among wild Japanese serows seem to be caused by at least two different parapoxviruses, bovine papular stomatitis virus and orf virus. The methods presented here are useful for genetic characterization and classification of parapoxviruses.
Amino Acid Sequence↗
Evolutionary relationships and systematics of the alphaviruses.
Partial E1 envelope glycoprotein gene sequences and complete structural polyprotein sequences were used to compare divergence and construct phylogenetic trees for the genus Alphavirus. Tree topologies indicated that the mosquito-borne alphaviruses could have arisen in either the Old or the New World, with at least two transoceanic introductions to account for their current distribution. The time frame for alphavirus diversification could not be estimated because maximum-likelihood analyses indicated that the nucleotide substitution rate varies considerably across sites within the genome. While most trees showed evolutionary relationships consistent with current antigenic complexes and species, several changes to the current classification are proposed. The recently identified fish alphaviruses salmon pancreas disease virus and sleeping disease virus appear to be variants or subtypes of a new alphavirus species. Southern elephant seal virus is also a new alphavirus distantly related to all of the others analyzed. Tonate virus and Venezuelan equine encephalitis virus strain 78V3531 also appear to be distinct alphavirus species based on genetic, antigenic, and ecological criteria. Trocara virus, isolated from mosquitoes in Brazil and Peru, also represents a new species and probably a new alphavirus complex.
3' Untranslated Regions↗
[Virus and systemic vasculitis].
The participation of genetic and environmental factors has always been invoked in the pathogenesis of the autoimmune systemic diseases, including the primary vasculitides. Among the environmental factors, infections, fundamentally those having a viral nature, have always been focused on, especially after the discovery of the close existing relationship between the polyarteritis nodosa and the hepatitis B virus, on the one hand, and mixed cryoglobulinemia and the hepatitis C virus, on the other. The present review summarizes data from the most recent literature related to associations between virus infections and primary vasculitides, following the Chapel-Hill vasculitis classification.
Humans↗
Oral hairy leukoplakia: pathogenetic aspects and significance of the lesion.
Oral hairy leukoplakia in HIV-seropositive persons is considered as a highly serious sign and places the patient in the AIDS-related complex group according to the classification recommended by the Centers for Disease Control. Epstein-Barr virus (EBV) is thought to be the cause. Based on the investigation of 14 of our own cases and a review of the literature, we conclude that so called hairy leukoplakia does not have a specific histopathologic pattern. Identical lesions can be caused by fungus infection, or biting and other kinds of mechanical irritation. Both fungal infection and EBV infection have been proven in a high percentage of the lesions. However, EBV has been found also in apparently normal oral mucosa. This questions the assumption that the virus is the cause of the lesions. In our investigation the presence of "hairy leukoplakia" did not reflect the clinical status of the patient. The best indicator of the clinical status was the T-lymphocyte subset CD4+ number in the peripheral blood. It appears that low CD4+ counts, candidiasis and the presence of replicating EBV in the epithelial cells are parallel markers of increasing immunodeficiency.
Adult↗
Genetic and antigenic heterogeneity of different parapoxvirus strains.
Six stomatitis papulosa and three Orf virus strains were compared by serology and by DNA restriction analysis. A neutralization kinetic study revealed extensive serological cross-reactivity between all strains, but did not allow their classification. Restriction analysis of viral DNAs revealed two distinct groups among the stomatitis papulosa strains while the Orf virus strains formed a third, more heterogeneous group. The large heterogeneity of restriction patterns of parapoxvirus DNAs as compared to those orthopoxviruses is discussed.
Antigens, Viral↗
Subcellular shift of the hepatic growth hormone receptor with progression of hepatitis C virus-related chronic liver disease.
AIMS: To evaluate the cytoplasmic and nuclear expression of hepatic growth hormone receptor (GHR) in different stages (S0, S1, S3 and S4, according to Knodell's classification) of chronic liver disease (CLD) and in hepatocellular carcinoma (HCC). METHODS AND RESULTS: Liver specimens from 31 patients with hepatitis C virus-related CLD, five patients with HCC and nine controls were examined for expression of hepatic GHR by immunohistochemistry with MAb 263. Cytoplasmic and nuclear staining were evaluated as a percentage of positively stained cells. The cytoplasmic expression of GHR was comparable between normal liver and S0 hepatitis, while it progressively decreased in S1, S3 and S4 CLD (P < 0.01). Conversely, nuclear GHR showed increased expression in S3 and S4 CLD (P < 0.05). No differences were observed between HCC and normal liver in terms of GHR immunoreactivity. CONCLUSIONS: This is the first study to show that the subcellular expression of hepatic GHR changes with the progression of CLD. The increase in nuclear expression of GHR with advanced stages of CLD suggests that GH may act directly at the nuclear level to promote hepatocyte proliferation/regeneration.
Adult↗