Sexually transmitted diseases in homosexual and bisexual males from a cohort of human immunodeficiency virus negative volunteers (Project Horizonte), Belo Horizonte, Brazil

Sexually transmitted diseases (STD) are very frequent in the whole world. Males who do not use a condom during their sexual relations are at great risk. We report cases of STD during six months of observation, among homosexual/bisexual males who participate in the Project Horizonte. There were 16 cases of genital warts, 6 cases of human immunodeficiency virus infection, 24 cases of unspecific urethritis, 28 cases of herpes simplex virus infection, 30 cases of syphilis, 58 cases of gonorrhea and 84 cases of pediculosis. We concluded that a condom must be used in all sexual relations and new counseling techniques are needed, to avoid this situation.     

Determinants and trends in perinatal human immunodeficiency virus type 1 (HIV-1) transmission in the metropolitan area of Belo Horizonte, Brazil: 1998 - 2005

Significant decrease in human immunodeficiency virus type 1 (HIV-1) vertical transmission has been observed worldwide in centers where interventions such as antiretroviral therapy (ART), elective cesarean section, and avoidance of breastfeeding have been implemented. This prospective cohort study aimed to assess the determinants of and the temporal trends in HIV-1 vertical transmission in the metropolitan area of Belo Horizonte, Brazil from January 1998 to December 2005. The rate of HIV-1 vertical transmission decreased from 20% in 1998 to 3% in 2005. This decline was associated with increased use of more complex ART regimens during pregnancy. Multivariate analysis restricted to clinical variables demonstrated that non ART, neonatal respiratory distress/sepsis and breastfeeding were independently associated with HIV-1 vertical transmission. When laboratory parameters were included in the model, high maternal viral load and non maternal ART were associated with HIV-1 vertical transmission. The results from this study confirm the impact of ART in the reduction of HIV-1 vertical transmission and indicate the need for improvement in the care and monitoring of mother and infant pairs affected by HIV-1.     

Risk factors for tuberculosis among human immunodeficiency virus-infected persons. A case-control study in Belo Horizonte, Minas Gerais, Brazil (1985-1996)

The objective of this study was to identify tuberculosis risk factors and possible surrogate markers among human immunodeficiency virus (HIV)-infected persons. A retrospective case-control study was carried out at the HIV outpatient clinic of the Universidade Federal de Minas Gerais in Belo Horizonte. We reviewed the demographic, social-economical and medical data of 477 HIV-infected individuals evaluated from 1985 to 1996. The variables were submitted to an univariate and stratified analysis. Aids related complex (ARC), past history of pneumonia, past history of hospitalization, CD4 count and no antiretroviral use were identified as possible effect modifiers and confounding variables, and were submitted to logistic regression analysis by the stepwise method. ARC had an odds ratio (OR) of 3.5 (CI 95% - 1.2-10.8) for tuberculosis development. Past history of pneumonia (OR 1.7 - CI 95% 0.6-5.2) and the CD4 count (OR 0.4 - CI 0. 2-1.2) had no statistical significance. These results show that ARC is an important clinical surrogate for tuberculosis in HIV-infected patients. Despite the need of confirmation in future studies, these results suggest that the ideal moment for tuberculosis chemoprophylaxis could be previous to the introduction of antiretroviral treatment or even just after the diagnosis of HIV infection.     

Isolation and antigenic characterization of human immunodeficiency virus (HIV) in Brazil

A retrovirus infecting a Brazilian AIDS patient was isolated and characterized in terms of its reactivity with sera from individuals infected with human immunodeficiency viruses 1 and 2 (HIV-1 and HIV-2). The Western blot analysis revealed that the Brazilian isolate is very similar to the well characterized HIV-1 strain. The serum of the patient from whom the virus was isolated did not react with the 140 kDa envelope glycoprotein specific for HIV-2.     

Course of HIV-I infection in a cohort of homosexual and bisexual men: an 11 year follow up study.

OBJECTIVE--To characterise the natural history of sexually transmitted HIV-I infection in homosexual and bisexual men. DESIGN--Cohort study. SETTING--San Francisco municipal sexually transmitted disease clinic. PATIENTS--Cohort included 6705 homosexual and bisexual men originally recruited from 1978 to 1980 for studies of sexually transmitted hepatitis B. This analysis is of 489 cohort members who were either HIV-I seropositive on entry into the cohort (n = 312) or seroconverted during the study period and had less than or equal to 24 months between the dates of their last seronegative and first seropositive specimens (n = 177). A subset of 442 of these men was examined in 1988 or 1989 or had been reported to have developed AIDS. MAIN OUTCOME MEASURES--Development of clinical signs and symptoms of HIV-I infection, including AIDS, AIDS related complex, asymptomatic generalised lymphadenopathy, and no signs or symptoms of infection. MEASUREMENTS AND MAIN RESULTS--Of the 422 men examined in 1988 or 1989 or reported as having AIDS, 341 had been infected from 1977 to 1980; 49% (167) of these men had died of AIDS, 10% (34) were alive with AIDS, 19% (65) had AIDS related complex, 3% (10) had asymptomatic generalised lymphadenopathy, and 19% (34) had no clinical signs or symptoms of HIV-I infection. Cumulative risk of AIDS by duration of HIV-I infection was analysed for all 489 men by the Kaplan-Meier method. Of these 489 men, 226 (46%) had been diagnosed as having AIDS. We estimated that 13% of cohort members will have developed AIDS within five years of seroconversion, 51% within 10 years, and 54% within 11.1 years. CONCLUSION--Our analysis confirming the importance of duration of infection to clinical state and the high risk of AIDS after infection underscores the importance of continuing efforts both to prevent transmission of HIV-I and to develop further treatments to slow or stall the progression of HIV-I infection to AIDS.     

Study on phlebotomine sand fly (Diptera: Psychodidae) fauna in Belo Horizonte, state of Minas Gerais, Brazil

A study on the phlebotomine sand fly fauna in Belo Horizonte city, state of Minas Gerais, Brazil, was carried out. From April 2001 to March 2003, monthly systematic collections were performed in three houses from each of the nine regions of the city, using CDC light traps for four consecutive days. The traps were set into the houses and in peridomestic areas totaling 54 traps. A number of 3871 sand fly specimens of the genera Lutzomyia and Brumptomyia were collected. Sixty eight percent of the specimens were L. longipalpis and 16% L. whitmani, insect vectors of visceral and American cutaneous leishmaniasis, respectively. Environmental factors such as temperature, humidity, and frequency of precipitation suggest that the number of insects increases after rainy periods. During the same period mentioned above, seasonal captures were carried out in parks and green areas of Belo Horizonte, using Shannon trap. A total of 579 phlebotomine sand flies were collected from which 398 (68.7%) were females with the predominance of L. whitmani and L. monticola. Those specimens were used for natural infection examination, by polymerase chain reaction. No Leishmania DNA was present in any of the specimens tested.     

Study of the cytogenetic effects of occupational exposure to pesticides on sanitation workers in Belo Horizonte, Brazil

Sanitation workers handling pesticides in the control of disease vectors constitute an occupationally exposed population to genotoxic substances. The aim of the present study was to investigate the relation between the occupational exposure to various pesticides and the presence of cytogenetic damage. Fifty-nine men were selected (29 sanitation workers and 30 control individuals) with ages varying between 18-57 years who lived and worked in the same area in Belo Horizonte (Brazil). The following parameters were determined for all individuals using the cytokinesis-block micronucleus (MN) assay in peripheral blood lymphocytes: MN/1000 binucleated cells (BC), BC with MN (BCMN)/1000 BC, nucleoplasmic bridges (NB)/1000 BC, apoptotic and necrotic cells/500 cells and nuclear division index. The analysis of covariance showed significantly higher (p < 0.05) mean frequencies of MN (15.81 +/- 1.31 vs 4.71 +/- 0.42), BCMN (15.10 +/- 1.22 vs 4.62 +/- 0.44), NB (4.59 +/- 0.76 vs 1.00 +/- 0.34), and necrotic cells (12.07 +/- 1.45 vs 5.17 +/- 0.70) in the exposed group when compared to the control group. There was no significant difference in the apoptotic cell frequency between the two groups, while the nuclear division index was significantly lower (1.49 +/- 0.02 vs 1.61 +/- 0.02) in the control group. Neither the time of exposure nor the smoking or alcohol drinking habit influenced the cytogenetic parameters examined. According to these results, occupational exposure to pesticides induced genotoxic and cytotoxic effects in sanitation workers.     

Sexual transmission of hepatitis C virus: cohort study (1981-9) among European homosexual men.

OBJECTIVE--To determine the prevalence, incidence, and persistence of positivity for antibodies to hepatitis C virus (anti-HCV) and the potential for sexual transmission of the virus. DESIGN--A cohort analysis covering 1981-9 comparing estimated cumulative incidences of and seroconversion rates for anti-HCV with those of hepatitis B core antibody (anti-HBc) and antibodies to the human immunodeficiency virus (anti-HIV). SETTING--Copenhagen and Aarhus, Denmark. SUBJECTS--259 Male members of a Danish homosexual organisation. MAIN OUTCOME MEASURES--Correlations of prevalence and incidence with a wide range of sexual lifestyle variables. RESULTS--Only four (1.6%) subjects were positive for anti-HCV in 1981. The estimated cumulative incidence of positivity for anti-HCV was 4.1% in 1984 (seroconversion rate during 1981-4 (2.5%)) and remained at 4.1% in 1989 (seroconversion rate nil during 1984-9). In contrast, positivity for anti-HBC rose from 44.0% in 1981 to 52.7% in 1984 (seroconversion rate 15.5%) and 58.8% in 1989 (seroconversion rate 12.9%), and that for anti-HIV rose from 8.8% to 24.0% (seroconversion rate 16.7%) and 30.1% (seroconversion rate 8.0%) respectively. Three anti-HCV positive patients seroreverted three to five years later. None of the anti-HCV positive subjects had had a transfusion and only one gave a past history of intravenous drug use. Variables in sexual lifestyle correlated with the presence of anti-HBc but not with that of anti-HCV. CONCLUSIONS--In contrast with hepatitis B virus and HIV, sexual transmission of hepatitis C virus seems to be a rare event. Furthermore, antibodies to the virus may become undetectable after several years.     

The transmission dynamics of human immunodeficiency virus (HIV)

The paper first reviews data on HIV infections and AIDS disease among homosexual men, heterosexuals, intravenous (IV) drug abusers and children born to infected mothers, in both developed and developing countries. We survey such information as is currently available about the distribution of incubation times that elapse between HIV infection and the appearance of AIDS, about the fraction of those infected with HIV who eventually go on to develop AIDS, about time-dependent patterns of infectiousness and about distributions of rates of acquiring new sexual or needle-sharing partners. With this information, models for the transmission dynamics of HIV are developed, beginning with deliberately oversimplified models and progressing--on the basis of the understanding thus gained--to more complex ones. Where possible, estimates of the model's parameters are derived from the epidemiological data, and predictions are compared with observed trends. We also combine these epidemiological models with demographic considerations to assess the effects that heterosexually-transmitted HIV/AIDS may eventually have on rates of population growth, on age profiles and on associated economic and social indicators, in African and other countries. The degree to which sexual or other habits must change to bring the 'basic reproductive rate', R0, of HIV infections below unity is discussed. We conclude by outlining some research needs, both in the refinement and development of models and in the collection of epidemiological data.     

Endosymbionts of Ctenocephalides felis felis (Siphonaptera: Pulicidae) obtained from dogs captured in Belo Horizonte, Minas Gerais, Brazil

Specimens of fleas Ctenocephalides felis felis (1052 female symbol/448 male symbol), obtained from 150 dogs in Centro de Controle de Zoonoses de Belo Horizonte, Minas Gerais, Brazil, were dissected and examined for endosymbionts. Three protozoan, Nolleria pulicis, a gregarine (Actinocephalidae) and Leptomonas sp., together with one cestode, Dipylidium caninum were identified. Infections by N. pulicis and Leptomonas sp. occurred mainly in the warm-rainy period. The prevalence and distribution of these endosymbionts in fleas derived from Brazil and South America, and the their variation according to sex and season, are reported for the first time.     

Parasite load and risk factors for poor outcome among children with visceral leishmaniasis. A cohort study in Belo Horizonte,Brazil, 2010-2011

Clinical and laboratory risk factors for death from visceral leishmaniasis (VL) arerelatively known, but quantitative real-time polymerase chain reaction (qPCR) mightassess the role of parasite load in determining clinical outcome. The aim of thisstudy was to identify risk factors, including parasite load in peripheral blood, forVL poor outcome among children. This prospective cohort study evaluated children aged≤ 12 years old with VL diagnosis at three times: pre-treatment (T0), during treatment(T1) and post-treatment (T2). Forty-eight patients were included and 16 (33.3%) metthe criteria for poor outcome. Age ≤ 12 months [relative risk (RR) 3.51; 95%confidence interval (CI) 1.89-6.52], tachydyspnoea (RR 3.46; 95% CI 2.19-5.47),bacterial infection (RR 3.08; 95% CI 1.27-7.48), liver enlargement (RR 3.00; 95% CI1.44-6.23) and low serum albumin (RR 7.00; 95% CI 1.80-27.24) were identified as riskfactors. qPCR was positive in all patients at T0 and the parasite DNA wasundetectable in 76.1% of them at T1 and in 90.7% at T2. There was no statisticalassociation between parasite load at T0 and poor outcome.     

Raman spectroscopic study on structure of human immunodeficiency virus (HIV) and hypericin-induced photosensitive damage of HIV

The first Raman spectra of HIV1-HIV2 in human sera and hypericin-induced photosensitive damage of the virus have been obtained. The prominent Raman lines in the spectra are assigned respectively to the carbohydrates of viral glycoprotein, RNA, protein and lipid. The spectra are dominated by Raman scattering of the carbohydrates. The lines of D-Mannose and N-acetylglucosamine in carbohydrates are obvious and there is a β-configuration in the anomeric C1 position in D-Mannose. The viral RNA duplexes bound assumes an A-form geometry. The lines of backbone phosphate group, bases (involving interbase hydrogen bonding) and ribose of the RNA are complete and distinct. The secondary structure of the viral protein maintains α-helix, β-sheet, β-turn and random coil. Its side chains are rich and vary from tryptophan, phenylalanine and “buried” tyrosine; the stable conformation of the S-S bond of gauche-gauche-gauche; the two forms of C-S bonds of gauche and trans; to sulfhydrl group and ionized and unionized carboxyl groups. The viral lipid bilayer molecules are probably in the liquid ordered phase or the gel phase. It was observed that the hypericin-induced photosensitive damage of HIV1-HIV2 in human sera changed various components of HIV1-HIV2 in different degrees: The orderly A-form viral RNA would become a disordered viral RNA. There were a breakage of interbase hydrogen bonds and disruption of vertical base-base stacking interactions. In addition, the groups of ribos and four bases were damaged obviously. A decrease in ordered structure (α-helix and β-sheet) of viral protein is accompanied by an increase in random coil. The Tyr buried in the three-dimensional structure of protein was damaged, but it was still “buried” and the damage of C-S bond of trans form was stronger. The groups of carbohydrates, including D-Mannos and N-acetyl glucosamine, in viral envelope glycoprotein had also been changed. The hydrophilic C-N bond of choline in viral lipid was damaged, which was the possible binding site to hypericin, whereas the viral lipids bilayers were still probably in the liquid ordered phase or the gel phase. So the space structure of HIV1-HIV2 was damaged under the experimental conditions, which might block viral infection and inhibit its growth and breeding. It is apparent that the laser Raman spectra have provided certain direct evidence at the molecular level for photosensitive damage of HIV1-HIV2.     

Raman spectroscopic study on structure of human immunodeficiency virus (HIV) and hypericin-induced photosensitive damage of HIV

Viruses are agents of some of the most destruc- tive diseases afflicting plants and animals[1]. Viruses also play a central role in experimental methods of molecular and cellular biology, especially in modern genetic engineering[1]. Raman spectroscopy is a pow-erful tool for studying the structure of the whole virion. A number of researches are limited to the conforma-tion of viruses, involving only nucleic acid (RNA or DNA) and its coat protein[1]. Literatures can be found concerning Raman…     

Prevalence of human immunodeficiency virus (HIV) infection among hemophiliacs in Fukuoka, Japan

To determine when the hemophiliacs in Fukuoka prefecture, Japan, first became positive for antibodies, we tested human immunodeficiency virus (HIV) antibodies on serum samples obtained from 1976-1987 stored at -30 C. Fifteen out of 64 hemophilia A patients (23.4%), five out of 11 hemophilia B patients (45.5%), but none of 17 patients with von Willebrand's disease (0%) were positive for HIV antibodies. In this series, two with hemophilia A became positive for HIV antibodies for the first time in 1983, and in 1984 another four with hemophilia A and one with hemophilia B became positive.     

Isolation of human immunodeficiency virus (HIV) from whole blood]

The authors describe a simple and sensitive technique for HIV isolation from small amounts of heparinized whole blood. This method demonstrated a high efficiency in detecting HIV at all stages of disease and appeared more sensitive with respect to viral isolation from peripheral blood mononuclear cells. Although further studies are needed to better understand the biological significance of a positive cultural result obtained by this method, HIV isolation from whole blood can be routinely employed, especially when small amounts of blood are available.