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PubMed2001

Variation in liposome binding among enteroviruses.

Liposome-binding properties of native virions and in vitro generated 135S particles of eight enteroviruses were studied. The temperature required for the structural transition from the native 160S virion to a 135S particle was virus-specific, ranging from +38 degrees C to more than +50 degrees C. While the 135S particles of poliovirus 1/Mahoney (PV1) and coxsackievirus A21 (CAV21) were capable of binding to liposomes, the other viruses showed minimal binding. Both of the viruses that bound to liposomes as 135S particles also bound as native virions. In addition, PV3/Sabin bound to liposomes as native virions but not as 135S particles, and the flotation patterns were different from those of PV1 and CAV21. The nonbinding viruses included coxsackieviruses A7, A9, A16, and B5, and enterovirus 68. The results follow the new classification of enteroviruses, as CAV21 is a member of the human enterovirus C species, which is genetically close to the poliovirus species.

Centrifugation, Density Gradient↗
PubMed1986

Xenotropic virus-related restriction patterns of non-H-2 histocompatibility mutant mice strains.

The relationship between alteration in the number of xenotropic virus-related sequences and non-H-2 histocompatibility (H) mutations in mice was investigated. Mutant classifications included gain, loss, and loss-gain mutations. Genomic DNA from a panel of non-H-2 H mutant strains on the C57BL/6 and BALB/c backgrounds was digested with a set of restriction enzymes with varying numbers of sites within endogenous xenotropic-related sequences. The digested DNA was then resolved on agarose gels. Southern blots of digested DNA were hybridized with the pXenv probe specific for the env sequence of xenotropic viral sequences. The number of hybridizing bands varied from 7 to 19, depending on the restriction enzyme and inbred background. Most mutant strains were identical in their restriction patterns to the respective background strains. However, two B6 mutant strains, KH84 and HZ54, differed from C57BL/6 at a single band which appeared to be inherited from BALB/c in the derivation of the two congenic strains. The HZ43 strain lacked a male-specific band shared by both C57BL/6 and BALB/c; this loss was evidently independent of the original mutation which was observed to be autosomal. However, the KH148B and KH84 strains on the C57BL/6 background lacked single B6 bands. Both mutants were classified as gain mutants. An examination of previous reciprocal graft rejection patterns and retrovirus linkage to non-H-2 H loci indicated a strong inverse relationship between a linked retroviral sequence and presentation of a non-H-2 H antigen. This inverse correlation is consistent with reports of gene inactivation following retroviral insertion.

Animals↗
PubMed1995

Characteristics and prognosis of primary liver cancer in young patients in China.

To investigate the clinicopathologic characteristics of primary liver cancer (PLC) in young adults, 77 patients aged 35 or younger were compared with 603 patients older than 35 years during the same period. In the young patients, PLC showed: (1) a low incidence detected at mass survey (young 15.6% vs older 28.7%, P < 0.05); (2) a low level of history of hepatitis (young 36.8% vs older 66.3%, P < 0.01); (3) a high incidence of positivity for hepatitis B surface antigen (HBsAg) (young 79.2% vs older 67.6%, P < 0.05); (4) a relatively low incidence of associated cirrhosis (young 64.9% vs older 90.7%, P < 0.01); (5) larger tumor size (PLC > 5 cm; young 87.0% vs older 73.0%, P < 0.01); and (6) a more advanced stage of the disease according to the TNM classification (stage III; young 29.9% vs older 18.2%, P < 0.05). It is suggested that hepatitis B virus (HBV) may play an important role in the development of PLC without associated liver cirrhosis in young patients. Close periodic surveillance of young adults who are positive for HBsAg is important to detect PLC at an early stage.

Adult↗
PubMed2003

Classification of cytotoxic T-cell and natural killer cell lymphomas.

Mature or peripheral T-cell lymphomas are uncommon, accounting for only 10% to 15% of all non-Hodgkin's lymphomas. The classification of these neoplasms has been controversial. In contrast to B-cell lymphomas, cytologic features have not been useful in defining disease entities, and cytologic grade has not helped predict the clinical course. Similarly, many entities of T-cell or natural killer (NK) cell derivation do not have a specific immunophenotype. Clinical features are of major importance in defining T-cell and NK cell neoplasms, and in some cases the clinical syndrome, may be more important than the precise cell of origin. The majority of cytotoxic T-cell and NK cell lymphomas arise in extranodal sites. The expression of cytotoxic molecules in these lymphomas may predispose to apoptosis by tumor cells and normal bystander cells. Three major categories of extranodal T/NK cell tumors are recognized in the World Health Organization (WHO) classification: extranodal NK/T, nasal-type; enteropathy-type; and subcutaneous panniculitis-like. Epstein Barr virus (EBV) is closely linked to nasal NK/T-cell lymphoma, but shows geographic and racial variations in other subtypes. Tumors resembling the prototype of nasal NK/T-cell lymphoma occur in a variety of extranodal sites, and are referred to as nasal-type. Hepatosplenic T-cell lymphoma is a more systemic disease derived from functionally immature cytotoxic cells, usually gammadelta T-cell origin. Cytotoxic T-cell lymphomas of mature gammadelta T-cell origin most often arise in mucocutaneous sites, and may resemble the prototypes of extranodal T/NK cell lymphoma: nasal, enteropathy-associated, and panniculitis-like. Cytotoxic T/NK cell lymphomas occur with increased frequency in the setting of immune suppression, especially following organ transplantation. The nodal T-cell lymphoma most often exhibiting a cytotoxic immunophenotype is anaplastic large cell lymphoma (ALCL). Primary cutaneous ALCL frequently but not invariably expresses cytotoxic molecules. While the majority of extranodal neoplasms are derived from innate immune effector cells of NK cell and T-cell origin (gammadelta greater than alphabeta), most nodal cytotoxic T-cell lymphomas probably belong to the adaptive immune system. Studies of these neoplasms may assist in unraveling the diversity of their normal counterparts.

Cell Lineage↗
PubMed1996

Blood cell markers.

Cytochemistry and immunocytochemistry are important adjunctive technologies to the morphologic characterization of blood cells and hematopoietic neoplasms. Although cytochemistry is briefly discussed, the emphasis of this article is on the clinical application of flow cytometry and leukocyte monoclonal antibodies in veterinary medicine. Classification and significance of immunophenotyping in canine and feline lymphomas and immunodeficiencies such as feline immunodeficiency virus and feline leukemia virus are discussed.

Animals↗
PubMed1995

[Etiology and differential diagnosis of sialadenitis].

The salivary glands are integrated into the body in such a complex manner that the analysis of the saliva allows conclusions about pathological function of other organ systems. Such interactions between salivary glands and the body as a whole play an important role in the etiology and pathogenesis of the different types of sialadenitis. An etiological classification is a proven method for arriving at a clinical diagnosis. Etiological factors include traumas, bacteria, viruses, ductal obstructions, disturbances of secretion, radiogenic damage, and immunological reactions (immunocomplex, tuberculin, or autoimmune types). Frequently the etiology is influenced by several factors. After a brief discussion of the clinical diagnostic methods, we present the clinical and morphological findings concerning the various types of sialadenitis and their differential diagnosis.

Diagnosis, Differential↗
PubMed2006

HIV genetic diversity in Cameroon: possible public health importance.

To monitor the evolving molecular epidemiology and genetic diversity of HIV in a country where many distinct strains cocirculate, we performed genetic analyses on sequences from 75 HIV-1-infected Cameroonians: 74 were group M and 1 was group O. Of the group M sequences, 74 were classified into the following env gp41 subtypes or recombinant forms: CRF02 (n = 54), CRF09 (n = 2), CRF13 (n = 2), A (n = 5), CRF11 (n = 4), CRF06 (n = 1), G (n = 2), F2 (n = 2), and E (n = 1, CRF01), and 1 was a JG recombinant. Comparison of phylogenies for 70 matched gp41 and protease sequences showed inconsistent classifications for 18 (26%) strains. Our data show that recombination is rampant in Cameroon with recombinant viruses continuing to recombine, adding to the complexity of circulating HIV strains. This expanding genetic diversity raises public health concerns for the ability of diagnostic assays to detect these unique HIV mosaic variants and for the development of broadly effective HIV vaccines.

Adult↗
PubMed1980

How ancient are the tobamoviruses?

The amino acid sequences of the virion proteins of 7 definitive tobamoviruses have been compared. The results show that the proteins may be arranged unequivocally in a single dendrogram which, by analogy with similar comparisons of other sets of homologous proteins, probably reflects their phylogeny. The magnitude of the differences between these sequences suggests that the tobamoviruses are at least as old as flowering plants. The sequence differences are significantly correlated with serological differences and with differences in amino acid composition, and so the latter was used to compute a classification of 13 tobamoviruses that also probably reflects their phylogeny. The possible ages of several other virus groups are discussed.

Amino Acid Sequence↗
PubMed1987

Cross-hybridization and relationships of various papillomavirus DNAs at different degrees of stringency.

Cloned DNAs of 21 different papillomaviruses which naturally infect mammals and one bird papillomavirus were compared for relative homology by Southern blot hybridization. Blots were carried out under low (Tm-40 degrees), medium (Tm-33 degrees), and high (Tm-22 degrees) stringency conditions. At higher stringency, human papillomaviruses cross-hybridized with each other reflecting species-specific similarities. Bovine papillomavirus types 1, 2, 5, European elk papillomavirus, and deer papillomavirus also cross-hybridized at higher stringencies probably reflecting the association of these viruses with fibroblast-prolific lesions. The hybridization data presented here may be useful in future classification attempts. They are also useful as a guide in the selection of papillomavirus DNA probes for analysis of extracts from warts and tumors.

Animals↗
PubMed2006

Comparative analysis of hepatitis C virus phylogenies from coding and non-coding regions: the 5' untranslated region (UTR) fails to classify subtypes.

BACKGROUND: The duration of treatment for HCV infection is partly indicated by the genotype of the virus. For studies of disease transmission, vaccine design, and surveillance for novel variants, subtype-level classification is also needed. This study used the Shimodaira-Hasegawa test and related statistical techniques to compare phylogenetic trees obtained from coding and non-coding regions of a whole-genome alignment for the reliability of subtyping in different regions. RESULTS: Different regions of the HCV genome yield inconsistent phylogenies, which can lead to erroneous conclusions about classification of a given infection. In particular, the highly conserved 5' untranslated region (UTR) yields phylogenetic trees with topologies that differ from the HCV polyprotein and complete genome phylogenies. Phylogenetic trees from the NS5B gene reliably cluster related subtypes, and yield topologies consistent with those of the whole genome and polyprotein. CONCLUSION: These results extend those from previous studies and indicate that, unlike the NS5B gene, the 5' UTR contains insufficient variation to resolve HCV classifications to the level of viral subtype, and fails to distinguish genotypes reliably. Use of the 5' UTR for clinical tests to characterize HCV infection should be replaced by a subtype-informative test.

5' Untranslated Regions↗
PubMed2006

Influenza-associated hospitalization in a subtropical city.

BACKGROUND: The impact of influenza on morbidity and hospitalization in the tropics and subtropics is poorly quantified. Uniquely, the Hong Kong Special Administrative Region has computerized hospital discharge diagnoses on 95% of total bed days, allowing disease burden for a well-defined population to be accurately assessed. METHODS AND FINDINGS: Influenza-associated morbidity and hospitalization was assessed by Poisson regression models for weekly counts of hospitalizations in Hong Kong during 1996 to 2000, using proportions of positive influenza types A (H1N1 and H3N2) and B isolations in specimens sent for laboratory diagnosis as measures of influenza virus circulation. We adjusted for annual trend, seasonality, temperature, and relative humidity, as well as respiratory syncytial virus circulation. We found that influenza was significantly associated with hospitalization for acute respiratory disease (International Classification of Diseases version 9 codes [ICD9] 460-466 and 480-487) and its subcategory pneumonia and influenza (ICD9 480-487) for all age groups. The annual rates of excess hospitalization per 100,000 population for acute respiratory diseases for the age groups 0-14, 15-39, 40-64, 65-74, and 75+ were 163.3 (95% confidence interval [CI], 135-190), 6.0 (95% CI, 2.7-8.9), 14.9 (95% CI, 10.7-18.8), 83.8 (95% CI, 61.2-104.2), and 266 (95% CI, 198.7-330.2), respectively. Influenza was also associated with hospitalization for cerebrovascular disease (ICD9 430-438) for those aged over 75 y (55.4; 95% CI, 23.1-87.8); ischemic heart disease (ICD9 410-414) for the age group 40-64 y (5.3; 95% CI, 0.5-9.5) and over 75 y (56.4; 95% CI, 21.1-93.4); and diabetes mellitus (ICD9 250) for all age groups older than 40 y. CONCLUSIONS: Influenza has a major impact on hospitalization due to cardio-respiratory diseases as well as on cerebrovascular disease, ischemic heart disease, and diabetes mellitus in the tropics and subtropics. Better utilization of influenza vaccine during annual epidemics in the tropics will enhance global vaccine production capacity and allow for better preparedness to meet the surge in demand that is inevitable in confronting a pandemic.

Adult↗
PubMed2000

[Equivalence between revisions of the International Classification of Diseases: causes of death].

OBJECTIVE: To evaluate the comparability of the underlying cause and multiple causes of death identified according to the ninth and tenth revisions of the International Classification of Diseases. METHODS: Study data was obtained by a random sample of 3,313 death certificates of individuals living in the State of S. Paulo and whose death was registered during the year of 1992. They corresponded to 1.6% of the total deaths of that year. The corresponding file was processed by the Automated Classification of Medical Entities system, and codes were assigned to all mentioned conditions. The underlying cause of death had been evaluated and revised according to the ninth revision. All the conditions mentioned on the medical form of the corresponding death certificates were coded according to the tenth revision and the codes were introduced in the original file in order to assess the causes of death by the Declarações de Obito de S. Paulo system to obtain the underlying cause of death. Multiple causes of death tabulations for both ninth and tenth revisions codes were produced by the respective versions of the Multiple Causes of Death Tabulator software. The comparisons of causes of death are circumscribed to the chapters of both revisions. RESULTS/CONCLUSIONS: The most important changes with the underlying causes of death occurred in chapters I, III and VIII of the ninth revision and the corresponding chapters I, IV and X of the tenth revision of the International Classification of Diseases. They were due to the displacement of deaths related to the human immunodeficiency virus disease and the dismissal of pneumonias as a cause of death. Regarding multiple causes of death, it was observed an increase ofrespiratory diseases and a corresponding reduction of causes included in the chapter of ill-defined affections due to recoding of respiratory failure.

Brazil↗
PubMed1990

[Intestinal spirochetosis in homosexuals infected with HIV. 3 cases].

We report 3 cases of intestinal spirochetosis in homosexuals infected with the human immunodeficiency virus (2 group III and 1 group IV C1, according to the Centers for Disease Control classification) presenting with moderate, chronic diarrhea. The diagnosis was made based on the histological examination of colorectal biopsies showing a layer of spirochetes carpeting the epithelium. Electron microscopy evaluation and culturing of the microorganism provided information on the bacterium's morphology. Metronidazole effectively treated the diarrhea. Intestinal spirochetes, whose existence has been recognized for more than a century, constitute a heterogeneous group of bacteria whose pathogenic role in man remains controversial. The systemic search for these organisms in a large series of patients would help to situate their place among the various etiologies of infectious diarrhea in immunodepressed subjects.

Adult↗
PubMed1980

Lymphomatoid granulomatosis.

The exact nature of lymphomatoid granulomatosis remains unclear. Whether it represents a viral infection, an autoimmune disorder (possibly induced by a virus), or primary malignant lymphoma, is still to be determined. The histopathology and clinical course allows classification of lymphomatoid granulomatosis as a distinct entity. Unfortunately, there is no consistently effective therapy for this condition and the usual course is rapidly downhill, though temporary remissions may be obtained. Since presentation of these patients with cutaneous lesions is not unusual, dermatologists must be alert to the possibility of an underlying systemic vasculitis in patients with atypical cutaneous ulceration, especially when no obvious cause is apparent.

Adult↗
PubMed1993

[Vaccination coverage in the districts of the city of Castellon and the relationship with sociodemographic factors: an ecologic study].

BACKGROUND: The state of vaccination in 1987 of those born in the city of Castellon and the relation with a group of sociodemographic variables by districts collected from a study based on the census of inhabitants of 1986 was analyzed. METHODS: The state of vaccination of each child was obtained from the Computerized Municipal Registry of Vaccinations with good vaccination being considered when the child had received all the doses corresponding to the age of two years (four doses of oral trivalent poliomyelitis and three doses of diphtheria-tetanus-pertussis and one dose of diphtheria-tetanus and one dose of triple virus) and was considered as badly vaccinated when one of the doses had been missed. Following classification of each child according to the district of residence, the effect of the state of vaccination, the sex of the child and the month of birth as well as the group of variables collected in the district (ecologic base), the relative risks were estimated by logistic regression analysis. RESULTS: Neither the sex of the child nor the month of birth had any relation with the risk of being badly vaccinated. Upon analysis of the effect being born in a determined district had, five presented between two and four times less risk of bad vaccination than that taken by reference (La Vila) and another three presented up to two times more risk. Among the significant predictors of risk of bad vaccination the following were found: crowding, old age, rate of dependence, rate of widowhood, and the proportion of single people, while the percentage of active women and the density of population were protective. In multivariant analysis, only the proportion of single people and the number of active women persisted as significant predictors. CONCLUSIONS: Although great inequality has been reported in vaccination coverage among the districts of the city of Castellon, the general coverage of the city may be considered as satisfactory in the light of the criteria used and from comparisons with other similar studies. The associations found between bad vaccination and some sociodemographic variables by districts (proportion of single people, and active women) together with possible methodologic limitations, do not allow the important inequalities found to be satisfactorily explained.

Child↗
PubMed1965

THE NATURE OF HERPES ZOSTER: A LONG-TERM STUDY AND A NEW HYPOTHESIS.

Dr Hope-Simpson presents a study of all cases of herpes zoster occurring in his general practice during a sixteen-year period. The rate was 3.4 per thousand per annum, rising with age, and the distribution of lesions reflected that of the varicella rash.It was found that severity increased with age, but that the condition did not occur in epidemics, and that there was no characteristic seasonal variation. A low prevalence of varicella was usually associated with a high incidence of zoster.Dr Hope-Simpson suggests that herpes zoster is a spontaneous manifestation of varicella infection. Following the primary infection (chickenpox), virus becomes latent in the sensory ganglia, where it can be reactivated from time to time (herpes zoster). Herpes zoster then represents an adaptation enabling varicella virus to survive for long periods, even without a continuous supply of persons susceptible to chickenpox.

Chickenpox↗
PubMed2004

Recent isolates of parapoxvirus of Finnish reindeer (Rangifer tarandus tarandus) are closely related to bovine pseudocowpox virus.

Cases of papular stomatitis in Finnish reindeer have been reported for many years. The causative agent was thought to be Orf virus (ORFV), one of the Parapoxviridae, although this assumption was based mainly on clinical symptoms, pathology and electron microscopy. Here sequence analyses of the viral DNA isolated from a recent outbreak of disease in 1999-2000 are presented in comparison to that isolated from earlier outbreaks in 1992-1994. The results show that the virus isolated from the 1999-2000 outbreak is most closely related to Pseudocowpox virus, whereas those from previous years grouped with ORFV. The present study describes a method for genetic characterization and classification of parapoxviruses (PPVs) and provides for the first time an extended phylogenetic analysis of PPVs isolated from Finland, established members of the genus Parapoxvirus and selected members of the subfamily Chordopoxvirinae.

Amino Acid Sequence↗