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PubMed2002

Fine-needle aspiration cytology of lymphoproliferative disorders in the immunosuppressed patient: the diagnostic utility of in situ hybridization for Epstein-Barr virus.

We examined the diagnostic utility of fine-needle aspiration (FNA) in the immunosuppressed patient with particular attention to the value of in situ hybridization for Epstein-Barr virus encoded RNA (EBER), a test frequently performed on tissue sections in this setting. Six patients with adenopathy were identified: three with prior solid organ transplantation, two with prior bone marrow transplantation, and one with human immunodeficiency virus. Cytologic findings in involved tissues were positive for non-Hodgkin's lymphoma in one case, suspicious or atypical in three cases, negative/reactive in one case, and nondiagnostic in one case due to insufficient material. Two aspirates had a polymorphous lymphoid appearance; three showed predominantly monomorphous lymphoid morphology. Retrospectively, 4/4 FNA cell blocks were positive for EBER in a large proportion of atypical lymphoid cells. Together with the cytologic findings, EBER detection allows for more specific classification of these FNA samples as EBV-associated lymphoid proliferations.

Adult↗
PubMed1996

[Genetic relatedness of the dengue 3 virus isolated in the outbreak of dengue hemorrhagic fever in Nicaragua, 1994].

It is reported the isolation of 2 dengue strains, 3 in samples from Nicaraguan patients suffering from dengue with hemorrhagic manifestations, which showed the reintroduction of this serotype in the region after being 17 years out of circulation. It is also reported the genetic characterization of the isolated strain, which, according to its classification, belongs to the group of dengue 2 strains isolated in Southeast Asi and which have been associated to hemorrhagic dengue. These results suggest the origin of this strain.

Amino Acid Sequence↗
PubMed1992

Semen analysis in human immunodeficiency virus infection.

OBJECTIVE: To examine the effect of human immunodeficiency virus (HIV) infection on semen quality and to investigate the role of clinical stage of infection, mode of virus acquisition, and azidothymidine (AZT) treatment. DESIGN, PATIENTS, MAIN OUTCOME MEASURES: Ejaculates from 39 HIV-seropositive men and 51 seronegative controls were compared using conventional semen analysis parameters. Centers for Disease Control (Atlanta, GA) classification and peripheral blood CD4 lymphocyte count of seropositive men were recorded at the time of semen analysis. Five patients provided semen before and after AZT treatment. RESULTS: Semen from seropositive men contained significantly fewer motile sperm (48.8% versus 58.8%, P = 0.001), more round cells (62% versus 28% subjects with density greater than 1 x 10(6)/mL, P = 0.003), and was more viscous (1.3 versus 0.5 cm, P less than 0.05) than semen from seronegative controls. The proportion of motile sperm was correlated with absolute number (r = 0.49, P = 0.004) and percentage (r = 0.37, P = 0.03) of CD4-positive lymphocytes in peripheral blood. Total sperm output, however, was preserved and was not correlated with lymphocyte count or symptomatic disease. Administration of AZT had no deleterious effect on sperm output or other semen variables. CONCLUSION: Human immunodeficiency virus infection per se does not significantly reduce sperm production, regardless of clinical stage or mode of acquisition; however, HIV-seropositive men produce more viscous semen containing fewer motile sperm and more round cells.

CD4 Antigens↗
PubMed2001

Detection of sporadic cases of hepatitis E virus (HEV) infection in China using immunoassays based on recombinant open reading frame 2 and 3 polypeptides from HEV genotype 4.

We reported previously on the complete sequence of hepatitis E virus (HEV) genotype 4, isolated from patients with sporadic cases of acute HEV infection in China. At least eight HEV genotypes have now been described worldwide, and further isolates await classification. Current immunoassays for the detection of anti-HEV antibodies are based on polypeptides from genotypes 1 and 2 only and may be inadequate for the reliable detection of other genotypes. Because genotypes 1 and 4 predominate in China, we wished to investigate the antigenic reactivities of HEV genotype 4 proteins. Four overlapping regions of open reading frame 2 (ORF2) (FB5, amino acids [aa] 1 to 130; E4, aa 67 to 308; F2-2, aa 288 to 461; E5, aa 414 to 672) and the entire ORF3 product were expressed in Escherichia coli as fusion proteins. Enzyme immunoassays based on each of the five purified polypeptides were evaluated with sera from patients with sporadic cases of acute HEV infection. Individual immunoassays derived from HEV genotype 4 detected more cases of acute hepatitis E than a commercial assay. Some serum samples, which were positive for anti-HEV immunoglobulin G only by assays based on HEV genotype 4, were positive for HEV RNA by reverse transcription-PCR. Polypeptide FB5, from the N terminus of ORF2, had the greatest immunoreactivity with sera from patients with acute hepatitis E. These data indicate that the N terminus of ORF2 may provide epitopes which are highly reactive with acute-phase sera and that assays based on genotypes 1 and 2 alone may be inadequate for the detection of HEV infection in China, where sporadic cases of HEV infection are caused predominantly by HEV genotypes 4 and 1.

Acute Disease↗
PubMedDate not supplied

[Genetic analysis of wild measles virus strains isolated in the european part of the Russian Federation].

Eleven wild measles virus isolated, in 1988 and in 1999-2001 in the European territory of the Russian Federation, were investigated. On the basis of an analysis of N-gene region sequences, encoding the COOH terminal end of nucleoprotein, the isolates were divided into 2 subgroups. According to the WHO classification, subgroup 1 was in line with genotype A and subgroup 2--with genotype D. Subgroup 2 was close to genotype D4 but differed from it according to its composition of nucleotides on the average by 2.8%, and according to its amino-acid composition--by 2.6%. with respect to the WHO criteria, the latter can be referred to preliminarily as an independent genotype. Finally, the measles viruses' strains of genetic groups A and D circulated in the Russian Federation in 1988, and in 1999-2001.

Adolescent↗
PubMed2004

HIV infections in northwestern Cameroon: identification of HIV type 1 group O and dual HIV type 1 group M and group O infections.

HIV-1 strain diversity was examined in a study population that consisted of hospital and clinic patients from seven cities and villages located in the northwestern regions of Cameroon. Specimens were screened using a serological algorithm designed to identify HIV-1 group M, N, and O, and SIVcpz-like infections followed by RT-PCR amplification to characterize the infecting virus. The results show that the HIV epidemic in northwest Cameroon is dominated by HIV-1 group M CRF02_AG infections (57%). Additional group M subtypes present include A, D, F2, G, and CRF01_AE. Based on discordant subtype classification between gag and env sequences, a high percentage (23%) of viral strains appear to be unique intersubtype recombinants with the majority (88%) involving recombination with CRF02_AG. Group O prevalence is low accounting for only 0.4% of HIV infections. However, group O strain diversity is high; isolates from clades I, IV, and V, as well as unclassified and recombinant strains, were found. Three dual infections by HIV-1 group M and group O were identified and characterized. In two specimens, both group M and O sequences were amplified in gag, pol, and env suggesting the presence of both viruses. Analysis of the third specimen shows the presence of a group O virus and an intergroup M/O recombinant virus. Finally, no infections due to HIV-1 group N or SIVcpz-like strains were found in the study population.

Amino Acid Sequence↗
PubMed1996

Heterogeneity of papillomaviruses.

The classification of the papillomaviral sequence into types is satisfactory for many purposes, but the resulting catalog does not accurately depict the extent of diversification of this family of viruses. Phylogenetic and mutational analyses reveal that some viral forms are much more ancient than other forms. Episodic evolutionary events and zoonotic transmission may have contributed to the overall pattern. Convergent evolution appears to be the best explanation for the scattered occurrence across the family tree of viruses with high oncogenic risk. We look for the determinants of this risk among the less conserved residues of the viral E6 and E7 transforming proteins.

Amino Acid Sequence↗
PubMed1999

Genetic diversity of pestiviruses: identification of novel groups and implications for classification.

The complete Npro coding sequences were determined for 16 pestiviruses isolated from cattle, pig, and several wild ruminant species including reindeer, bison, deer, and bongo. Phylogenetic analysis enabled the segregation of pestiviruses into the established species bovine viral diarrhea virus-1 (BVDV-1), BVDV-2, border disease virus (BDV), and classical swine fever virus (CSFV). For BVDV-1 five distinct subgroups were identified, while BVDV-2, BDV, and CSFV were each subdivided into two subgroups. The virus isolates from bongo and deer as well as one porcine virus isolate belong to BVDV-1. Interestingly, the isolates from reindeer and bison are distinct from the established pestivirus species. The Npro sequences from these two viruses are more similar to BDV than to the other pestivirus species. Calculation of the pairwise evolutionary distances allowed a clear separation of the categories species, subgroup, and isolate only when the reindeer/bison viruses were considered as members of an additional pestivirus species. Furthermore, the entire E2 coding sequences of a representative set of virus isolates covering all recognized species and subgroups were studied. Segregation of pestiviruses based on the E2 region was identical with that obtained with the N(pro) sequences.

Amino Acid Sequence↗
PubMed2003

Molecular characterization of segments 7-10 of Dendrolimus punctatus cytoplasmic polyhedrosis virus provides the complete genome.

The nucleotide sequences of genomic segments S7-S10 from Dendrolimus punctatus cypovirus strain Hunan (DpCPV-Hn) have been determined. This provides the complete genome sequences of DpCPV-Hn. Each segment of S7-S10 possess a single segment each. Homology searches showed that the nucleotide sequences and the deduced amino acid sequences of DpCPV S7-10 had high level of identities with those of Bombyx mori cypovirus (BmCPV) S7-10, respectively. While the amino acid sequences of the proteins encoded by DpCPV S7 and S8 have low identities with those of the proteins encoded by type 14 Lymantria dispar cypovirus S7 and S8, respectively. DpCPV S7 encodes viral structural protein VP5, S8 and S9 encode viral non-structural proteins, and S10 encodes polyhedrin gene, according to the function of the genome segments of BmCPV. There are glutamic-acid-rich and proline-rich domains in the central region of DpCPV S8 encoded protein. A nuclear localization signal was found in the protein encoded by DpCPV S9. Phylogenetic analysis of RNA-dependent RNA polymerases from nine viruses of the family Reoviridae and polyhedrin from eight viruses of the genus Cypovirus indicate that DpCPV is a type 1 cypovirus, more closely related to BmCPV than to other cypovirus species. These results also support the classification of CPV groups based on the electrophoretic migration of genomic dsRNA.

Animals↗
PubMed2005

Mitochondrial markers for molecular identification of Aedes mosquitoes (Diptera: Culicidae) involved in transmission of arboviral disease in West Africa.

Correct classification of the insect vector is central to the study of arboviral disease. A simple molecular method for identification of the main vectors of the mosquito-borne viruses, dengue, yellow fever, and Rift Valley fever in Senegal, West Africa, was developed. We present a system in which the five mosquito species (Diptera: Culicidae) responsible for the majority of flaviviral disease transmission in Senegal can be reliably identified using small amounts of DNA coextracted during flaviviral screening procedures, via an easy amplification of the mitochondrial gene cytochrome oxidase c subunit I or II (COI or COII, respectively). We observed that despite very similar morphology, the two cryptic disease vector species Aedes furcifer Edwards and Aedes taylori Edwards are highly divergent at the molecular level. This sequence variation was used as a basis for the development of a polymerase chain reaction-restriction fragment-length polymorphism system for the differentiation of the two species. We also present the first investigation of the phylogeny of the culicine mosquitoes based on all COI and COII sequences currently available. There seems to be very low intraspecific variation in both genes, whereas interspecific variation is high. As a consequence, COI and COII are ideal candidates for the molecular identification of disease vectors to species level, whereas deeper divergences remain equivocal by using these genes. This system provides a new technique for the accurate identification of culicine disease vectors in West Africa and provides a basis for the expansion of such methods into the study of a range of diseases.

Aedes↗
PubMed1997

Are HTLV-II-seropositive injection drug users at increased risk of bacterial pneumonia, abscess, and lymphadenopathy?

Disease associations of HTLV-II are poorly defined, despite a high seroprevalence among injection drug users (IDU). One hundred twenty-four HTLV-II-seropositive emergency room and clinic patients were matched by age, sex, and clinic to 120 HTLV-I/II-seronegative patients. Medical records were reviewed blinded to HTLV-II status, and International Classification of Disease 9th Clinical Modification (ICD-9CM)-coded diagnoses were compared between seropositive patients and controls. After adjustment for relevant confounding variables such as human immunodeficiency virus infection, HTLV-II-seropositive IDU had an increased risk of bacterial pneumonia (odds ratio [OR], 3.45; 95% confidence interval [CI], 1.58, 7.56), abscess (OR, 8.30; 95% CI, 4.02, 17.11), and lymphadenopathy (OR, 3.91; 95% CI, 1.24, 12.32) compared with HTLV-II-negative non-IDU patients. In contrast, HTLV-II-negative IDU were at only marginally increased risk of the same conditions, with OR of 1.76 (95% CI, 0.42, 7.40), 3.00 (95% CI, 0.94, 9.59), and 1.31 (95% CI, 0.15, 11.66), respectively. These results indicate that HTLV-II seropositivity may define a subgroup of IDU who are at particularly high risk of bacterial pneumonia, skin and soft tissue abscess, and lymphadenopathy. Whether HTLV-II has an etiologic role in predisposing IDU to bacterial infections and lymphadenopathy will require further investigation.

Abscess↗
PubMed2004

Molecular detection and genotyping of male-specific coliphages by reverse transcription-PCR and reverse line blot hybridization.

In recent years, there has been increased interest in the use of male-specific or F+ coliphages as indicators of microbial inputs to source waters. Sero- or genotyping of these coliphages can also be used for microbial source tracking (MST). Among the male-specific coliphages, the F+ RNA (FRNA) viruses are well studied, while little is known about the F+ DNA (FDNA) viruses. We have developed a reverse line blot hybridization (RLB) assay which allows for the simultaneous detection and genotyping of both FRNA as well as FDNA coliphages. These assays included a novel generic duplex reverse transcription-PCR (RT-PCR) assay for FRNA viruses as well as a generic PCR for FDNA viruses. The RT-PCR assays were validated by using 190 field and prototype strains. Subsequent DNA sequencing and phylogenetic analyses of RT-PCR products revealed the classification of six different FRNA clusters, including the well-established subgroups I through IV, and three different FDNA clusters, including one (CH) not previously described. Within the leviviruses, a potentially new subgroup (called JS) including strains having more than 40% nucleotide sequence diversity with the known levivirus subgroups (MS2 and GA) was identified. We designed subgroup-specific oligonucleotides that were able to genotype all nine (six FRNA, three FDNA) different clusters. Application of the method to a panel of 351 enriched phage samples from animal feces and wastewater, including known prototype strains (MS2, GA, Q beta, M11, FI, and SP for FRNA and M13, f1, and fd for FDNA), resulted in successful genotyping of 348 (99%) of the samples. In summary, we developed a novel method for standardized genotyping of F+ coliphages as a useful tool for large-scale MST studies.

Animals↗
PubMed1997

Diagnosis of human immunodeficiency virus type 1 infection in infants by immune complex dissociation p24 assay.

Using immune complex dissociation (ICD), we retrospectively examined serum and plasma of 206 infants aged 0 to 4 months who were perinatally exposed to human immunodeficiency virus (HIV). All samples were analyzed in a blinded manner. Infection status was determined based on the results of HIV culture and Centers for Disease Control and Prevention classification. The overall diagnostic sensitivity of the assay was 59% (93 samples, 73 infants), and specificity was 100% (160 samples, 133 infants). When the samples were analyzed according to age, sensitivity was highest at age 1 to 2 months (17 of 21 infants, 81%). Sensitivities at other ages were 53% at < 1 month, 55% at 2 to 3 months, and 48% at 3 to 4 months (9 of 17, 11 of 20, and 12 of 25 cases, respectively). In 11 evaluable cases there was a possible correlation of p24 antigen quantitation (in picograms per milliliter) with disease progression. We conclude that, as determined in this study, the ICD p24 is a rapid diagnostic assay for HIV infection with a sensitivity of >80% at 1 to 2 months of age and 100% specificity, as evaluated, up to 4 months of age.

Antigen-Antibody Complex↗
PubMed1971

Classification of North American porcine enteroviruses: a comparison with European and Japanese strains.

Seventy-two strains of porcine enteroviruses including strains from North America, England, and Japan were compared by cell culture neutralization tests to provide a serological classification of North American strains. From the tests, eight serogroups evolved, with serogroup 8 having a possible three subgroups. There appeared to be some intergroup relationship among certain viruses in groups having the same specific cytopathic effect (CPE) in cell culture. There was no apparent cross-reaction between the group with type II CPE and groups with type I CPE. Antisera produced in nonhost chickens provided a satisfactory antibody source for the tests. It was proposed that satisfactory typing of viruses could be done best by cross-neutralization rather than by one-way neutralization tests. This provided the homologous serum titer as determined in the laboratory conducting the tests which was important where comparisons are made on the basis of per cent of the homologous titer. It was further emphasized that viruses of tissue origin and their antisera have fewer intergroup reactions than viruses of intestinal origin and their antisera. General type strains and specific North American strains were suggested as satisfactory type sera and viruses for seven of the eight groups to facilitate virus identification.

Animals↗
PubMedDate not supplied

[The hepatitis B virus in alcoholic liver disease: its clinical and biochemical assessment].

The aim of our work was to study the prevalence of HBV markers in Alcoholic Liver Disease (ALD) by evaluating clinical and biochemical parameters that could further characterize the association. A prospective and sequential study of 107 patients with ALD was performed, including 83 cases of cirrhosis and 24 cases of alcoholic hepatitis. Daily ingestion of pure ethanol was of at least 70 gm for seven years or more and always associated with hepatocellular disfunction. According to the serological profile for HBV markers the patients were allocated to one of four groups: group I infected (positivity of HBsAg and anti-HBc); group II immunized (positivity of anti-HBs and anti-HBc); group III without HBV markers (negativity of HBsAg, anti-HBc and anti-HBs); group IV isolated anti-HBc. The prevalence of HBsAg positivity in ALD was high: 15.89% whereas immunity was low: 26.17% suggesting a great exposure to the virus and a deficient immunological response. No significant statistical differences were found among the three groups when clinical and biochemical parameters were individually considered. Nevertheless, when a Child/Campbell classification was applied, patients with ALD associated with HBV (group I) showed a significant difference, presenting a predominance of child C, with a bad prognosis.

Adult↗
PubMed1991

Superficial oral fungal infections.

Fungal infections in humans are provoked and exacerbated by defects in the cellular immune system. Hence, the emergence of novel clinical variants of oral candidoses and rare mycoses with the pandemic spread of human immunodeficiency virus infection is not surprising. The new clinical entities of oral candidoses that have been described in the past few years have had a significant impact on the classification of these diseases. Classification of oral candidoses is an issue addressed in some detail here. Angular cheilitis is a disease commonly associated with Candida infection. In the West, it is frequently seen in the elderly, but a report from Asia indicates that the disease may be prevalent in the young age groups due to factors such as anemia, despite the similarity of the infective agents. A novel cofactor implicated in infectious states has been the host blood group secretor status, and data from three studies suggest that the latter may play an intriguing role in the pathogenesis of oral candidosis. Finally, a new mouse model has been described as a substitute for the rat model in investigating the host-parasite interactions in oral candidosis, and its pros and cons are reviewed.

Acquired Immunodeficiency Syndrome↗
PubMed1989

[Characteristics and role of the gluteal herpes in a female population].

Based on the fact that the gluteal herpes may constitute the clinical expression of the reactivation of a Herpes simplex virus latent at the sacral lymph node, we investigated a group of women who were carriers of gluteal herpetic infection, the characteristics of the infection, the virus type principally associated to it, and its possible relation with the genital herpes. Forty one women with gluteal herpes verified by virologic laboratory were studied. 75.7% of these women had had in addition to this herpetic infection in other places, mainly genital, with an average of 7.2 of recurrent episodes per year, (range: 1 to 18 episodes yearly). 78% of the isolated virus was typified as HSV-2 by the use of monoclonal antibodies. It is stand out the importance of considering the background of gluteal herpes as causative of classification of herpetic high risk.

Adolescent↗
PubMed1994

Human sentinels for arbovirus surveillance and regional risk classification in South Australia.

OBJECTIVES: To assess the use of human sentinels to monitor arbovirus activity in South Australia and to use age-specific seroprevalence data from the same sentinels to classify regions according to risk from Ross River virus (RRV). METHODS: Between 1 January 1992 and 15 August 1992, 4776 serum samples were obtained from Red Cross blood donors in the State. All sera were tested for the presence of total antibody (IgA, IgG and IgM) by indirect enzyme immunoassay. To test for recent infection, positive sera were further tested for IgA and IgM specific antibody to Ross River virus with a view to initiating public health interventions if necessary. The age, sex and postcode of residence of each donor were also recorded for seroepidemiological studies. RESULTS: Of the 4776 sera, 2952 were tested to the end of May (the end of the arbovirus season in South Australia). There was evidence of RRV infection in 248 sera (8.4%) but none had serological markers consistent with recent infection. The arbovirus season was considered non-epidemic, and no reactive public health interventions were introduced. Analysis of age-specific seroprevalence by post-code in the full bank of 4776 sera indicated that the Riverland is endemic for RRV, the Murray Mallee and Upper South East epidemic for RRV, and the remaining regions of the State at variable risk, depending on their proximity to these regions. CONCLUSIONS: The ongoing use of human sentinels is a new public health surveillance system for this disease. In the first year of operation of this surveillance system, a suboptimal number of sera was collected from some areas, and sera were tested only for RRV. However, the number of sera tested could easily be increased, as could the range of arboviruses covered by the testing.

Adult↗