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At least 523 records · Page 29Linked to original sources
PubMed1994

Nucleotide sequence of the genes encoding the canine herpesvirus gB, gC and gD homologues.

The nucleotide sequence of the genes encoding the canine herpesvirus (CHV) gB, gC and gD homologues was determined. These genes are predicted to encode polypeptides of 879, 459 and 345 amino acids, respectively. Comparison of the predicted amino acid sequences of CHV gB, gC and gD with the homologous sequences from other herpesviruses indicates that CHV is an alphaherpesvirus, a conclusion that is consistent with the previous classification of this virus according to biological properties. Alignment of the homologous gB, gC and gD amino acid sequences indicates that most of the cysteine residues are conserved, suggesting that these glycoproteins possess similar tertiary structures. The nucleotide sequence of the open reading frame downstream from the CHV gC gene was also determined. The predicted amino acid sequence of this putative polypeptide appears to be homologous to a family of proteins encoded downstream from the gC gene in most, although not all, alphaherpesviruses.

Amino Acid Sequence↗
PubMed2003

Molecular resolution of a complex of potyviruses infecting solanaceous crops at the centre of origin in Peru.

Peru is a centre of origin and domestication of the potato, pepper and tomato (family Solanaceae). Many potyviruses (genus Potyvirus) that infect these crops were described 20-30 years ago. However, definitive classification of these viruses as distinct species remains unresolved for several reasons, including their close serological relationships, similar symptomatology in test plants and lack of genomic sequence data. Using samples collected from Peru, we have determined the complete genomic sequence of two strains of Peru tomato virus (PTV) as well as near-complete sequences for two additional PTV strains. We also obtained partial sequences of four strains of Potato virus V (PVV). Comparisons with genomic sequences of Wild potato mosaic virus (WPMV), Potato virus Y (PVY), Pepper mottle virus (PepMoV), Potato virus A (PVA) and other potyviruses established that all these viruses constitute different taxa (species). Phylogenetic comparisons indicated that PTV, PVV and WPMV are the most closely related species which, together with PepMoV, PVY, Pepper yellow mosaic virus and Pepper severe mosaic virus, constitute a group that is distinguishable from other potyviruses. Therefore, the members of this group may share a common ancestor. PVA does not belong to this group. PVV and PTV were also closely related serologically. However, PTV did not cross-protect against PVV and WPMV in tobacco plants or complement systemic infection of PVV and WPMV in pepper plants. Two biologically and phylogenetically distinguishable strain groups were identified within PTV and PVV. In future studies, the sequence data and virus-specific primers and probes for PTV, PVV and WPMV described in this study will enable accurate indexing of plants with respect to either single or mixed infection with these viruses.

Capsicum↗
PubMed1995

Human papillomaviruses (HPV) in gynaecological cytology: from molecular biology to clinical testing.

Molecular epidemiological and pathological studies show that different HPV types are associated with different cervical lesions allowing classification of the viruses into types associated with 'high', 'intermediate' and 'low' risk of cervical neoplasia. However, HPV infection often regresses and, where it is associated with neoplasia, is an early event. This suggests that other factors are involved in the carcinogenic process, and there is some mechanistic basis for the interaction of epidemiologically defined factors with HPV infection in the process of cervical carcinogenesis. With the refinement of techniques for HPV detection in clinical material, HPV testing is now a realistic possibility, but how this should be performed and in what clinical situation(s) is still uncertain. Particular areas of interest are: (i) the assessment of patients with borderline cytological changes or mild dyskaryosis; and (ii) the definition of those patients at greater risk of invasive disease. Clinical trials are needed before the utility of HPV testing can be properly assessed.

Cell Transformation, Neoplastic↗
PubMed2002

Biological and biochemical characterization of sheep scrapie in Japan.

Due to the apparent absence of an agent-specific nucleic acid genome, scrapie strains cannot be classified by genome characterization, which is commonly used for the classification of many viruses. However, scrapie strains can be distinguished to some extent by biological properties such as transmissibility to experimental animals and distribution of neuropathological lesions and by biochemical properties such as the molecular mass and relative protease-resistance of the disease-specific isoform of prion protein (PrP(Sc)). In order to preliminarily characterize the scrapie strains that are prevalent in Japan, we analyzed the transmissibility of sheep scrapie isolates to mice and the relative proteinase K (PK) resistance of the corresponding PrP(Sc). The results indicate that Japanese scrapie strains can be divided into at least three groups based on biological and biochemical properties. The first group includes isolates which cause disease in mice with an incubation period of approximately 400 days and possess PrP(Sc) with relatively high PK resistance. Isolates of the second group contain PrP(Sc) that is highly resistant to PK digestion but transmit poorly to mice. The final group consists of isolates that cause disease in mice with an incubation period of less than 300 days and are associated with PrP(Sc) with reduced PK resistance. Sheep scrapie has occurred sporadically in Japan since1982, with only approximately 60 officially reported cases so far. However, the diversity of scrapie strains in the field suggested by our data raises the concern that a scrapie strain similar to the parental agent of bovine spongiform encephalopathy could exist or emerge in Japan. Thus, continuous surveillance for scrapie will be required to prevent the further spread of scrapie, not only among the sheep population but also to other species, and to eliminate any potential risk of sheep scrapie to public health.

Animals↗
PubMed2000

Primary structure of the Herpesvirus ateles genome.

Herpesvirus ateles is an agent indigenous to spider monkeys (Ateles spp.) and causes fulminant lymphomas in various New World primates. Structural and genetic relatedness led to the classification of this virus as a member of the genus Rhadinovirus. It is most closely related to Herpesvirus saimiri. The 108,409-bp light DNA segment of the herpesvirus ateles strain 73 genome has two genes for U-RNA-like transcripts and 73 open reading frames, of which at least 6 show significant homologies to cellular genes (encoding complement control proteins, apoptosis-regulatory proteins, D-type cyclins, interleukin-8 receptors, and enzymes involved in nucleotide metabolism). The left terminal region of the light DNA segment bears the putative rhadinovirus oncogene tio.

Amino Acid Sequence↗
PubMed2006

[Epidemiologic surveillance of measles and rubella in Campinas (SP), Brazil: the reliability of the data].

OBJECTIVE: To evaluate and validate the information concerning measles and rubella from the Brazilian National Disease Notification System (BNDNS) (Sistema Nacional de Informação de Agravos de Notificação, or SINAN) for Campinas, a large city in the state of São Paulo, Brazil, using as a reference the data from a control system, the Syndromic Surveillance System for Fever and Exanthem (SSSFE) (Sistema de Vigilância Sindrômica de Febre e Exantema, or VigiFEx), which operated from May 2003 through June 2004. METHOD: In our study we compared: (1) annual data from BNDNS for the years 1999 through 2003 and (2) data from BNDNS and data from SSSFE for the period of June 2003 through May 2004. We analyzed the rate of completion for key fields (record number, date of notification, and city of notification) as well as for name of disease, date of first symptoms, name of patient, birth date and age, sex, city of residence, date of investigation, immunization history, presence of exanthem, date at start of exanthem, presence of fever, suspected cases among pregnant women, signs and symptoms, date of collection of first sample, results with the sample, virus isolation, final classification, criteria for confirmation/exclusion of cases, diagnosis of excluded patients, development of the case, and date of closure. The level of agreement between the recorded cases in the two data banks was also analyzed. RESULTS: From June 2003 through May 2004, 211 suspected cases of measles or rubella were identified in SSSFE and 275 in BNDNS. All the records had complete information concerning the three key fields. The rate of completion was also 100% for patient name, disease, and city of residence. The completion rate was higher than 95% for date of investigation, measles vaccine, measles and rubella vaccine, and rubella vaccine. A lower completion rate was found for other vaccination variables (number of doses and date of last dose) and for exanthem, fever, and date of start of exanthem. The two information systems were not completely consistent, particularly in terms of variables related to epidemiologic background, clinical data, and case closure. The quality of the SSSFE data was higher. CONCLUSIONS: Epidemiologic surveillance, immunization, and laboratory information systems need to undergo routine evaluation to ensure that the data are reliable and can support the planning of public health efforts.

Adult↗
PubMed1982

Acute non-A, non-B hepatitis in Norway. Clinical, epidemiological, and immunological characteristics in comparsion with hepatitis A.

Serological analysis by radioimunoassay of sera from 297 patients hospitalized with acute non-toxic hepatitis was used for classification according to virus etiology. Radioimmunoassays included tests for hepatitis B surface antigen (HBsAg), antibody to HBsAg (anti-HBs), antibody to hepatitis A virus (anti-HAV), anti-HAV of IgM class, and antibody against cytomegalovirus (GMV) and Epstein-Barr virus. One patient with a significant rise in anti-CMV antibodies was classified as having CMV hepatitis. Among the 296 remaining patients serological markers indicated hepatitis A in 51 cases (17.2%) and hepatitis B in 208 cases (70.3%). The remaining 37 patients (12.5%) fulfilled criteria for acute non-A, non-B hepatitis. This type of hepatitis had symptoms and signs indistinguishable from those of hepatitis A, except for a slight tendency to milder disease on admission. A considerable proportion of patients with non-A, non-B hepatitis had a history of drug abuse (43.2%) and of recently traveling to endemic hepatitis areas (29.7%). In the remaining 27.1% no particular background was revealed. No case of post-transfusion hepatitis was seen. During the last 6 months of the study a striking change in epidemiology concerning hepatitis A was seen, apparently caused by a steep increase in the incidence of this type of hepatitis among drug addicts. No significant difference in biochemical liver tests was seen in non-a, non-B hepatitis or hepatitis A. In contrast, a marked and statistically significant difference in serum concentrations of IgM was found, with higher values (mean, 7.5 g/1; range, 3.2-13.9 g/1) in hepatitis A than in non-a, non-B hepatitis (mean, 3.3 g/1; range, 0.9-9.4 g/1). This difference may have diagnostic value.

Acute Disease↗
PubMed1999

Multiplex polymerase chain reaction for subgenus-specific detection of human adenoviruses in clinical samples.

The polymerase chain reaction (PCR) has been used previously for the detection and typing of adenoviruses directly in clinical samples. Since under clinical conditions subgenus-specific identification is often sufficient, we extended the genus- and type-specific PCR by a subgenus-specific PCR. By sequencing several loop I4 gene regions of the hexon (major adenovirus coat protein) and comparing them to published sequences, subgenus-specific sequences were identified in this region. By using primers targeted to this region and to a conserved hexon gene region, a multiplex, nonnested PCR for the detection and subgenus-specific identification of adenoviruses could be established. The six subgenus-specific amplimers are distinguishable by agarose gel electrophoresis, and subsequent restriction analysis is not necessary. The specificity of the subgenus-specific primer pairs was tested on 23 adenovirus prototypes, representing all six subgenera, on 9 subgenus B and D intermediate strains, and on 16 subgenus C genome types. Furthermore, multiplex, subgenus-specific PCR was performed directly with 100 clinical specimens, including stool samples, ocular swabs, and throat swabs. Adenoviruses of all subgenera could be detected. Especially for clinical application, the rapid, one-step differentiation between subgenus D adenoviruses, causing the severe and highly contagious epidemic keratoconjunctivitis, and subgenus B and E adenoviruses, causing relative harmless ocular infections, is of great importance. The subgenus-specific PCR could also facilitate the primary classification of unknown virus isolates.

Adenovirus Infections, Human↗
PubMed2000

Diagnosis of human papillomavirus gynecologic infections.

The identification in the early 1980s of human papillomavirus (HPV) DNA in cervical carcinoma generated interest in molecular classification of the virus, and prompted studies regarding the oncogenic potential of genital HPVs. Subsequent studies confirming the presence of HPV in greater than 90% of precancerous cervical lesions and close to 100% of cervical cancers has raised concerns regarding the adequacy of Papanicolaou (Pap) smear testing for the detection of precancerous lesions/HPV infection. A variety of detection methods adjunctive to cytologic testing have been described, including detection at the macroscopic level, cerviography, colposcopy, and serologic and molecular-based HPV testing. Recently, there has been intense interest in molecular-based detection and typing of HPV-induced genital lesions. This has resulted in the development of a variety of molecular-based detection methods including Southern transfer, dot blotting, in situ hybridization, hybrid capture, and PCR-based assays. This article provides an overview of each of the molecular methods, and addresses the potential future role of molecular-based HPV testing.

Antibodies, Viral↗
PubMed2003

Radio-frequency ablation in cirrhotic patients with hepatocellular carcinoma.

Current surgical treatments for hepatocellular carcinoma (HCC) include radio-frequency ablation (RFA), resection, and orthotropic liver transplant (OLT). RFA is particularly attractive in these high-risk patients because surgery is associated with high mortality and there is a relative scarcity of organs available for those in need of transplants. This study was performed to evaluate the management of cirrhotic patients with HCC undergoing RFA at a single Western institution. A retrospective study from March 1999 to June 2002 was performed to evaluate the clinicopathologic and treatment-related variables in cirrhotic patients with HCC. Forty-nine lesions in 26 patients with HCC and cirrhosis underwent RFA. Data was analyzed for safety and overall survival as the main endpoints. The mean age was 60.4 +/- 11 years, 19 patients were male, 5 had hepatitis B virus, and 19 had hepatitis C virus. The Child classification was 26 per cent, 39 per cent, and 35 per cent for A, B, and C; the number of lesions was 1 in 62 per cent, 2 in 23 per cent, and more than 2 in 15 per cent. The approach was laparoscopic in 58 per cent, percutaneous in 15 per cent, and open in 27 per cent. There were no mortalities and only 1 complication. Average hospital stay was 2.7 +/- 2 days. Subsequent to RFA, 9 patients underwent an OLT within a median of 4.1 months. The median follow-up of the whole group was 13 months and the disease-free survival 9.3 months. Tumor recurrence was identified in 3 previously ablated lesions, nonablated liver in 11, and as pulmonary metastases in 3. Overall survival (P = 0.03) was prolonged for those treated with RFA + OLT over RFA alone. We conclude that RFA is a safe ablative technique in high-risk cirrhotic patients with HCC. This technique may provide a bridge to OLT; however, it remains to be proven whether it prolongs survival in those who do not undergo OLT.

Adult↗
PubMed2005

WHO Expert Consultation on rabies.

More than 99% of all human rabies deaths occur in the developing world, and although effective and economical control measures are available, the disease has not been brought under control throughout most of the affected countries. Given that a major factor in the low level of commitment to rabies control is a lack of accurate data on the true public health impact of the disease, this report of a WHO Expert Consultation begins by providing new data on the estimated burden of the disease and its distribution in the world. It also reviews recent progress in the classification of rabies viruses, rabies pathogenesis and diagnosis, rabies pre- and post-exposure prophylaxis, the management of rabies patients, and canine as well as wildlife rabies prevention and control. Considering the emergence of new lyssaviruses and changes in animal and human rabies epidemiology observed on different continents, the definition of a rabies-free country or area has been revised to assist public health authorities in better assessing the risk of human rabies resulting from contact with animals. Measures aiming at preventing the spread of rabies through the international transfer of animals, mainly with regard to pets, are discussed as well as the new systems in place within and outside WHO to share rabies data and information. As certain tools currently used in rabies prevention and control, such as biologicals, tests for intra vitam and postmortem diagnosis, vaccines and immunoglobulin quality control, need improvement, the report ends by outlining the priorities for basic research, as well as those for operational research for sustainable canine rabies control, including dog population management schemes complying with animal welfare principles. Such operational research is necessary for removing or alleviating the main constraints to rabies control in dogs, as these are the source of most human rabies cases worldwide.

Animals↗
PubMed1983

[Diagnosis of nonrheumatic myocarditis].

Titres of antibodies neutralizing Coxsackie B1-6 virus were examined in 272 patients with nonrheumatic myocarditis and myocarditic cardiosclerosis, and also in two groups of controls (150 normal subjects and 70 patients with other cardiac diseases). A group of 123 patients were screened simultaneously for antibodies to Coxsackie B virus, influenza, parainfluenza, adenoviruses and beta-hemolytic Group A streptococcus. The diagnosis of myocarditis was based on clinical, electrocardiographic, enzymologic and functional electrocardiographic findings. Serologic data demonstrated that most cases of nonrheumatic myocarditis were associated with Coxsackie and influenza viruses. An etiologic classification, diagnostic criteria and problems of differential diagnosis of nonrheumatic myocarditis are discussed.

Clinical Enzyme Tests↗
PubMed1998

Nucleotide sequences of the 26S mRNAs of the viruses defining the Venezuelan equine encephalitis antigenic complex.

Genetic relationships among viruses defining the Venezuelan equine encephalitis (VEE) virus antigenic complex were determined by analyzing the 3'-terminal 561 nucleotides of the nonstructural protein 4 gene and the entire 26S RNA region of the genome. New sequence information is reported for VEE 78V-3531 (VEE subtype-variety IF), Mucambo (IIIA), Tonate (IIIB), 71D-1252 (IIIC), Pixuna (IV), Cabassou (V), and AG80-663 (VI) viruses. The results reported here and by previous investigators largely support the current classification scheme of these viruses, while clearly identifying Everglades (II) as a subtype I virus. A genetic relationship between 78V-3531 (IF) and AG80-663 (VI) viruses contradicted previous serologic results. Mutations near the amino terminus of the E2 envelope proteins of Pixuna and AG80-663 viruses probably account for the previously reported low reactivity of the protective monoclonal antibody 1A2B-10 with these two viruses. Variations in the distribution of potential glycosylation sites in the E2 glycoprotein are discussed.

Amino Acid Sequence↗
PubMed2022

Revisiting Papillomavirus Taxonomy: A Proposal for Updating the Current Classification in Line with Evolutionary Evidence.

Papillomaviruses infect a wide array of animal hosts and are responsible for roughly 5% of all human cancers. Comparative genomics between different virus types belonging to specific taxonomic groupings (e.g., species, and genera) has the potential to illuminate physiological differences between viruses with different biological outcomes. Likewise, extrapolation of features between related viruses can be very powerful but requires a solid foundation supporting the evolutionary relationships between viruses. The current papillomavirus classification system is based on pairwise sequence identity. However, with the advent of metagenomics as facilitated by high-throughput sequencing and molecular tools of enriching circular DNA molecules using rolling circle amplification, there has been a dramatic increase in the described diversity of this viral family. Not surprisingly, this resulted in a dramatic increase in absolute number of viral types (i.e., sequences sharing <90% L1 gene pairwise identity). Many of these novel viruses are the sole member of a novel species within a novel genus (i.e., singletons), highlighting that we have only scratched the surface of papillomavirus diversity. I will discuss how this increase in observed sequence diversity complicates papillomavirus classification. I will propose a potential solution to these issues by explicitly basing the species and genera classification on the evolutionary history of these viruses based on the core viral proteins (E1, E2, and L1) of papillomaviruses. This strategy means that it is possible that a virus identified as the closest neighbor based on the E1, E2, L1 phylogenetic tree, is not the closest neighbor based on L1 nucleotide identity. In this case, I propose that a virus would be considered a novel type if it shares less than 90% identity with its closest neighbors in the E1, E2, L1 phylogenetic tree.

Animals↗
PubMed1994

Kaposi's sarcoma of the head and neck in patients with acquired immunodeficiency syndrome.

Kaposi's sarcoma is the most common neoplastic process in patients infected with the human immunodeficiency virus. Moreover, the occurrence of Kaposi's sarcoma in human immunodeficiency virus-infected patients advances their classification to having the acquired immunodeficiency syndrome. We reviewed the medical records of 48 patients with human immunodeficiency virus infection who had Kaposi's sarcoma documented on their initial visit to the hospital. The onset of Kaposi's sarcoma occurred independent of the Centers for Disease Control and Prevention classification of human immunodeficiency virus infection (modified to exclude Kaposi's sarcoma). This neoplasm developed more frequently in patients who acquired human immunodeficiency virus infection by sexual contact (75% of cases), but manifestations were not significantly different in any of the risk populations for human immunodeficiency virus infection. Kaposi's sarcoma lesions were unpredictable and either showed progression, remained static, or occasionally, regressed spontaneously. Moreover, the lesions were usually multifocal at presentation, with the head and neck (62.5% of cases) as the primary site of involvement. In this region cutaneous lesions predominated (66.7%), followed by mucosal (56.7%) and deep structure (13.3%) involvement. The majority of patients with acquired immunodeficiency syndrome Kaposi's sarcoma involving head and neck structures were asymptomatic (80% of cases). Mucosal lesions were associated with symptoms in 29.3% of cases, whereas cutaneous lesions had symptoms in 5% of cases.

Acquired Immunodeficiency Syndrome↗