Showing papers by "Oswaldo Cruz Foundation published in 1995"

Plantas do pantanal

Abstract: 631RESENHA / REVIEWMissao na Selva Emil Odebrecht (1835-1912), umprussiano no Brasil Moacir Werneck de Castro Riode Janeiro: AC&M, 1994Ja havia resenhado o livro de Moacir Werneck deCastro sobre Fritz Muller, mas neste ele se superouLogo no inicio, uma frase do Doutor Blumenausobre o vale do Itajai, naquela epoca: “Aqui pareceque tudo parou no primeiro dia da Criacao” asseme-lha-se a definicao de Euclides da Cunha para a Ama-zonia: “Terra ainda quente do Genesis”Muito interessante a descricao da area em que seergueria a cidade de BlumenauFoi muito agradavel encontrar a formacao da Colo-nia Itajai, atual cidade de Brusque, onde iniciei a mi-nha carreira de pesquisadorCom respeito as amizades de Odebrecht, edestacada a importância da Sociedade dos Atirado-res, como a que conheci em Brusque, no papel denucleo de onde nasceram outras associacoes impor-tantes para o desenvolvimento da coloniaO grande parteiro de Blumenau, Friedenreich, quese registrara na colonia como veterinario, por ser fo-ragido da justica, aqui aparece como medico diploma-do e com pratica na AlemanhaUm debate sobre a construcao da ferrovia para oplanalto, entre os tres grandes pioneiros de Blume-nau, Odebrecht, Fritz Muller e Friedenreich, realizadonuma clareira da floresta, e do maior interesse para oentendimento da mentalidade desses grandes homensCom base na correspondencia trocada entre osmembros daqui e da Alemanha, o autor reconstitui avida da famflia OdebrechtDeixa a melhor impressao o respeito que Ode-brecht tinha pelos indios e a sua revolta contra asmatancas, as vezes patrocinadas por autoridadesgovernamentaisAo comentar a atuacao de Odebrecht na Repar-ticao dos Telegrafos, o autor aproveita para incluiruma pequena biografia do Barao de Capanema,figurailustre de brasileiro pouco conhecidoEm boa hora, o autor anexou ao livro o diario daexpedicao de Odebrecht as cabeceiras dos formado-res do rio Itajai-Acu Ali pode ser visto a durezaque e o trabalho de um engenheiro exploradorMario B Aragao

Causal inference in infectious diseases.

Abstract: Since the 1970s, Rubin has promoted a model for causal inference based on the potential outcomes if individuals received each of the treatments under study. Commonly, the assumption is made that the outcome in one individual is independent of the treatment assignment and outcome in other individuals. In infectious diseases, however, whether one person become infected is quite often dependent on the infection outcome in other individuals, a situation known as dependent happenings. Here, we review the model proposed by Rubin for the example of infectious disease. Consequences of the violation of the stability assumption include the need for an expanded representation of outcomes, and the existence of different kinds of effects, such as direct and indirect effects. Effects of interest include changes in susceptibility as well as changes in infectiousness. We define the transmission probability formally as an average causal parameter of effect in a population by conditioning on exposure to infection. Unconditional indirect and total effects are difficult to define formally using this model for causal inference. The assignment mechanism can influence the sampling mechanism when it determines who is exposed to infection, raising problems that require further inquiry. We conclude by contrasting the role of differential exposure to infection in direct and indirect effects.

Polymerase chain reaction detection of trypanosoma cruzi in human blood samples as a tool for diagnosis and treatment evaluation

Abstract: Trypanosoma cruzi specific sequences were amplified by the polymerase chain reaction from total blood of human chagasic patients and normal individuals. A 330 bp fragment originating from kinetoplast DNA was specifically detected in most chagasic individuals. We tested the sensitivity and specificity of this method in normal and affected individuals attending the Evandro Chagas Hospital, Rio de Janeiro. The results of these tests were compared with serological diagnosis performed using standard techniques, and in some cases with xenodiagnosis. We found that none of the serologically negative individuals gave any specific amplification product, whereas 55 out of 61 patients previously serodiagnosed as chagasic were positive using the PCR method (sensitivity: 90%). Xenodiagnosis, which is currently considered to be the most sensitive parasitological technique for Chagas' disease diagnosis, detected only 12 out of 28 serologically positive patients (sensitivity: 43%). The usefulness of the PCR method was further investigated with chagasic patients who had received anti-parasite treatment with benznidazole. It has always been difficult to evaluate the incidence of cure in such cases by serology, since a humoral response against T. cruzi antigens may remain for years even in the absence of the parasite. We observed a positive amplification result in only 9 out of 32 treated patients who remained reactive when tested using classical serology. These observations suggest that PCR is the most sensitive technique available for direct detection of T. cruzi in chagasic patients and that it can be a very useful instrument for the follow-up of patients after specific treatment.

Effect of paternal age in achondroplasia, thanatophoric dysplasia, and osteogenesis imperfecta

Abstract: The paternal ages of nonfamilial cases of achondroplasia (AC) (n = 78), thanatophoric dysplasia (TD) (n = 64), and osteogenesis imperfecta (OI) (n = 106), were compared with those of matched controls, from an Italian Indagine Policentrica Italiana sulle Malformazioni Congenite and a South American Estudio Colaborativo Latinoamericano de Malformaciones Congenitas series. The degree of paternal age effect on the origin of these dominant mutations differed among the three conditions. Mean paternal age was highly elevated in AC, 36.30 +/- 6.74 years in the IPIMC, and 37.19 +/- 10.53 years in the ECLAMC; less consistently elevated in TD, 33.60 +/- 7.08 years in the IPIMC, and 36.41 +/- 9.38 years in the ECLAMC; and only slightly elevated in OI in the ECLAMC, 31.15 +/- 9.25 years, but not in the IPIMC, 32.26 +/- 6.07 years. Increased maternal age or birth order in these conditions disappeared when corrected for paternal age. Approximately 50% of AC and TD cases, and only 30% of OI cases, were born to fathers above age 35 years. For AC and TD, the increase in relative incidence with paternal age fitted an exponential curve. The variability of paternal age effect in these new mutations could be due, among other reasons, to the high proportion of germ-line mosaicism in OI parents, or to the localization of the AC gene, mapped to the 4p16.3 region, in the neighborhood of an unstable DNA area.

Nematóides do Brasil. Parte IV: nematóides de aves

Abstract: A survey of nematode species parasitizing Brazilian birds is presented, with enough data to provide their specific identification. The first section refers to the survey of the species, related to 17 superfamilies, 23 families, 75 genera and 257 species that are illustrated and measurement tables are given. The second section is concerned to the catalogue of host birds which includes 54 families. 361 species. and their respective parasite nematodes. The identification of these helminths is achieved by means of keys to the superfamilies. families and genera. Specific determination is induced through the figures and tables as above mentioned.

HIV infection of human choroid plexus: a possible mechanism of viral entry into the CNS.

Abstract: The present study examines the hypothesis that HIV infection of the choroid plexus (CPx) may be an important site of viral entry into the brain. Formalin-fixed, paraffin-embedded CPx was obtained from 25 patients with AIDS and 13 nonAIDS patients and was processed for light microscopy and for immunohistochemical detection of HIV gp41, T and B lymphocytes, monocytes/macrophages and endothelial cells. Eleven of the 13 nonAIDS CPx were normal and 2 contained inflammatory foci of undetermined etiology. The stroma contained T lymphocytes in all and monocytes in 22%; B lymphocytes and HIV antigen were absent. Choroid plexus of the AIDS cases contained opportunistic infections or lymphoma in 12 and inflammatory foci alone in 6; 7 were normal. T lymphocytes were present in 70% and monocytes in 50%. In addition to the stromal localization, monocytes also were present in supra-epithelial regions and within or adjacent to the capillary endothelium. HIV-positive cells in the CPx were found in 11 cases (44%) and in the supra-epithelial area in another 2. Their presence correlated with neither infection nor lymphoma of the CPx or brain. They were situated in the stroma, supra-epithelial region and (rarely) capillary endothelium. Immunohistochemistry on serial sections identified the HIV-infected cells as monocytes, including those by capillary endothelium and in supra-epithelial areas. The study demonstrates that the CPx contains HIV-infected monocytes in almost half of the cases. Their apposition to endothelium suggests hematogenous origin. These results support the hypothesis that HIV encephalitis may develop from CPx infection.

Simian malaria at two sites in the Brazilian Amazon: I-The infection rates of Plasmodium brasilianum in non-human primates

Abstract: The parasite that causes simian malaria in the Brazilian Amazon, Plasmodium brasilianum, is infective to man In this region, where humans live within and in close proximity to the forest, it was suspected that this parasite could be the cause of a zoonosis A study was performed in the areas surrounding two hydroelectric plants in the Amazon, Balbina and Samuel, aiming at determining the zoonotic potential of this parasite P brasilianum was detected in, respectively, 158% and 99% of 126 and 252 primates belonging to seven and eight species examined from Balbina and Samuel The highest malaria infection rates were found among the red-howler monkey Alouatta seniculus straminea (323%), the bearded-saki Chiropotes satanas chiropotes (50%) and the spider-monkey Ateles paniscus paniscus (2[1+]) from Balbina and in the squirrel-monkey Saimiri ustus (21%) and the black-faced-spider-monkey Ateles paniscus chamek (286%) from Samuel

The social geography of AIDS in Brazil

Abstract: The first of a series of papers concerning the evaluation of the dynamics of the AIDS epidemic in Brazil employing techniques of geographical analysis, is here presented. Results of research undertaken in the US (especially in New York City) are compared with those of a recent investigation carried out in the city of S.Paulo, Brazil (Grangeiro, 1994). In both, geographical patterns of socio-demographic variables correlate with different patterns of the spread of the AIDS epidemic through the transmission groups. Recent trends of the AIDS epidemic in Brazil: the displacement toward medium sized cities and expansion frontiers, increasing report of AIDS cases among the poor and underprivileged, changes in the pattern of transmission with proportional augmentation of heterosexual transmission and IDUs as transmission groups, are described and analised. The geographical distribution of the AIDS cases registered between 1987-1993 in Brazil throughout the Brazilian States is evaluated by means of worksheets, maps, and non-parametric statistics. Results show that Gravimetric Centers (obtained by the use of the calculus spatial means) of AIDS in Brazil are situated within a triangle the sides of which are formed lines joining the three main metropolitan areas of the wealthiest region of Brazil - the southeast, i.e. Sao Paulo, Rio de Janeiro and Belo Horizonte. These especially S. Paulo, function as points of attraction for these Gravimetric Centers (GCs) towards the south as compared with the GCs of the general population calculated ia accordance with data from the 1980 and 1991 censuses. It is possible to observe a displacement of the GCs toward the northwest over this period in accordance with the migration patterns of the Brazilian population in general, though with a dynamic of its own. These changes in the geographical, socio-demographic and transmission group patterns show the complex nature of the epidemic in Brazil and pose additional difficulties for the development of prevention strategies.

Cellular immune response to Mycobacterium leprae infection in human immunodeficiency virus-infected individuals.

Abstract: The immune responses to Mycobacterium leprae and other mycobacterial antigens were studied in 11 leprosy patients with concurrent human immunodeficiency virus type 1 (HIV-1) infection. Three patients manifested borderline lepromatous leprosy, and eight patients had borderline tuberculoid (BT) leprosy. Despite the low CD4+ T-cell count in the peripheral blood, no histologic or phenotypic change in the cellular infiltrate in either the lepromatous or tuberculoid lesions was observed when compared with HIV-1-negative patients. Lepromatous lesions contained heavily parasitized macrophages and few CD8+ T cells. Lesions from the patients with BT leprosy showed extensive CD4+ T-cell infiltration despite a significant reduction in CD4+ T-cell counts in the peripheral blood. No acid-fast bacilli were detected in the tuberculoid lesions. HIV-1 infection did not alter the lack of response in lepromatous leprosy to M. leprae antigens either in vitro or in vivo. In contrast, the skin test response to M. leprae antigens as well as the in vitro lymphoproliferative responses to mycobacterial antigens that are usually seen in patients with tuberculoid leprosy were abrogated in the BT HIV-1+ patients. However, production of gamma interferon in response to the same stimuli was preserved in most of the patients. Analysis of cytokine gene expression showed activation of additional cytokine genes in the unstimulated peripheral blood cells of patients with both leprosy and HIV-1 infections as compared with cells from patients with leprosy alone. These results suggest that granuloma formation in leprosy can be independent of the impaired CD4+ T-cell response of the HIV-1 infection. Furthermore, in HIV-1+ individuals with M. leprae infection, activation of cytokine genes is observed even when the circulating CD4+ T-cell count is significantly reduced.

Flow cytometry, a new approach to detect anti-live trypomastigote antibodies and monitor the efficacy of specific treatment in human Chagas' disease.

Abstract: Sera from patients chronically infected with Trypanosoma cruzi display antibodies that bind to epitopes of living trypomastigotes, known as lytic antibodies (LA), and are detected by a complement-mediated lysis test. Conventional serology antibodies (CSA) are also present in sera from patients with chronic infections but, in contrast to LA, are unable to recognize viable trypomastigotes. The presence of LA has been used as an important element in the criterion of cure in human Chagas' disease. Using flow cytometry technology, we introduced a new and sensitive immunomethod for the detection of anti-live trypomastigote membrane-bound antibodies. On the basis of serological tests (LA and CSA detection) and parasitological assays such as hemoculture (HE), patients were classified into the following groups: chronically infected untreated patients (NT) and treated not-cured patients (TNC), with positive HE and both LA and CSA in their sera; "dissociated" HE-negative patients (DIS), in whom LA was not detected whereas CSA were present; a group of cured HE-negative patients (CUR), who were both LA and CSA negative; and, as control, a group of non-chagasic individuals (NC). Sera from these patients were assayed by incubation with live bloodstream trypomastigotes, which were subsequently exposed to fluorescein isothiocyanate-conjugated anti-human immunoglobulin G. The parasites were then fixed, run in the cytometer, and identified on basis of their size and granularity gain adjustments. On the basis of experience with the complement-mediated lysis test, a level of 20% of parasites being fluorescein isothiocyanate fluorescence positive was used as a cutoff between effective and ineffective treatments. With this criterion, our results indicated that sera from NT and TNC patients were antibody positive whereas all sera from DIS, CUR, and NC patients did not contain membrane-bound antibodies. This new approach is a tool to easily identify anti-live T. cruzi membrane-bound antibodies that can be used to monitor the efficacy of Chagas' disease treatment.

Treatment of bancroftian filariasis in Recife, Brazil: a two-year comparative study of the efficacy of single treatments with ivermectin or diethylcarbamazine

Abstract: The effectiveness of single oral doses of ivermectin (200 or 400 micrograms/kg) and diethylcarbamazine (DEC, 6 mg/kg), preceded 4 d earlier by either placebo or very small doses of these drugs, was compared, over a 2-year period, in a double-blind trial in 67 microfilaraemic Brazilian men with bancroftian filariasis. Regimens containing ivermectin alone decreased the number of microfilariae significantly faster and more effectively for the first month after treatment than regimens containing DEC alone, but the latter were significantly more effective throughout the second year after treatment (1.7-8.2% of pretreatment levels with DEC vs. 12.6-30.8% with ivermectin during that period); the higher ivermectin dose showed a tendency towards more effectiveness than the lower dose. Most effective was the combination of ivermectin (20 micrograms/kg) followed 4 d later by DEC (6 mg/kg), with reduction of microfilaraemia to 2.4% of pretreatment levels at 2 years. Adverse reactions were well tolerated with all regimens, the reactions being significantly more generalized (i.e., fever) following ivermectin and localized (i.e., scrotal inflammatory nodules around dying adult worms) following DEC. Further trials of single-dose combination therapy vs. single high doses of ivermectin or DEC should determine the ideal regimen for treatment and control of bancroftian filariasis.

Integrated control measures against Culex quinquefasciatus, the vector of filariasis in Recife

Abstract: Integrated control measures against Culex quinquefasciastus have been implemented in a pilot urban area in Recife, Brazil. About 3,000 breeding sites found within the operational area were responsible for very high mosquito densities recorded during the pretrial period. Physical control measures have been applied to cess pits before starting a series of 37 treatments of the other sites with Bacillus sphaericus strain 2362, over 27 months. In spite of the difficulties due to environmental conditions, very significant reductions in preimaginal population of C. quinquefasciatus were achieved and, as a consequence, low adult mosquito densities were maintained for a relatively long period of time. Entomological and environmental data gathered in this pilot project can contribute to design an integrated mosquito control program in Recife city.

Direct assessment of the adulticidal efficacy of a single dose of ivermectin in bancroftian filariasis

Abstract: Although the potent microfilaricidal activity of ivermectin is well established, its efficacy against adult Wuchereria bancrofti is unknown. We used longitudinal ultrasound examinations for periods of 3–9 months to assess directly the macrofilaricidal effect of a single 400 μg/kg dose of ivermectin in 15 men from Recife, Brazil who were infected with W. bancrofti. Before treatment, microfilarial densities ranged from 3 to 3098 microfilariae per mL of blood, and movements characteristic of the living adult worm (the ‘filaria dance sign’) were observed by ultrasound examination of the scrotal lymphatic vessels in all 15 men. Following treatment, microfilarial density was markedly reduced in all men, but the filaria dance sign remained unchanged in both location and pattern. Eight months after treatment, a dilated lymphatic vessel was surgically removed from one patient at the site of the filaria dance sign, and 3 intact adult worms were released. When given as a single 400 μg/kg dose, ivermectin had no observable effect on adult W. bancrofti. Therefore, prolonged suppression of microfilaraemia following treatment with ivermectin cannot be explained by a macrofilaricidal effect of the drug. Ultrasound is a valuable new tool for directly and rapidly assessing the macrofilaricidal efficacy of antifilarial drugs in lymphatic filariasis.

Assessing the Efficacy of a Mixed Vaccination Strategy against Rubella in São Paulo, Brazil

Abstract: Rubella is a viral infection which causes a mild disease. Teratogenic effects do however occur in 20-50% of children born to women during the first trimester of pregnancy. The goal of rubella vaccination should therefore be to prevent the adverse effects of congenital rubella syndrome caused by intrauterine rubella infection. A major vaccination strategy against measles-mumps-rubella was introduced in 1992 in the state of Sao Paulo Brazil based upon mathematical models and comprised of a pulse vaccination covering all children aged 1-10 years followed by the inclusion of the vaccine in the routine calendar at 15 months of age. This paper reports the evaluation of the efficacy of this mixed vaccination strategy. A rubella seroprevalence survey was conducted on 4953 children aged 1-15 years immediately and one year after the campaign showing the average rubella seroprevalence to have increased from 0.40 to 0.97 over the period. There was a commensurately dramatic drop in the reported number of congenital rubella syndrome cases.

Seroprevalence of HIV, HTLV-I/II and other perinatally-transmitted pathogens in Salvador, Bahia.

Abstract: Generation of epidemiological data on perinatally-transmitted infections is a fundamental tool for the formulation of health policies. In Brazil, this information is scarce, particularly in Northeast, the poorest region of the country. In order to gain some insights of the problem we studied the seroprevalence of some perinatally-transmitted infections in 1,024 low income pregnant women in Salvador, Bahia. The prevalences were as follow: HIV-1 (0.10%), HTLV-I/II (0.88%), T.cruzi (2.34%). T.pallidum (3.91%), rubella virus (77.44%). T.gondii IgM (2.87%) and IgG (69.34%), HBs Ag (0.6%) and anti-HBs (7.62%). Rubella virus and T.gondii IgG antibodies were present in more than two thirds of pregnant women but antibodies against other pathogens were present at much lower rates. We found that the prevalence of HTLV-I/II was nine times higher than that found for HIV-1. In some cases such as T.cruzi and hepatitis B infection there was a decrease in the prevalence over the years. On the other hand, there was an increase in the seroprevalence of T.gondii infection. Our data strongly recommend mandatory screening tests for HTLV-I/II, T.gondii (IgM), T.pallidum and rubella virus in prenatal routine for pregnant women in Salvador. Screening test for T.cruzi, hepatitis and HIV-1 is recommended whenever risk factors associated with these infections are suspected. However in areas with high prevalence for these infections, the mandatory screening test in prenatal care should be considered.

New subjects; new rights: the debate about the psychiatric in Brazil

Abstract: O autor analisa e debate as discussoes existentes em tomo do processo da reforma psiquiatrica brasileira, assim como em tomo do Projeto de Lei Paulo Delgado, que propoe a extincao dos hospitais psiquiatricos e sua substituicao por outras tecnologias de cuidado em saude mental. Para o autor a questao central esta no conceito de desinstitucionalizacao, em oposicao ao de desospitalizacao, onde o aspecto da Etica e o fundamental a discemir os rumos do projeto da reforma psiquiatrica.

Comparison of antibody isotype responses to Schistosoma mansoni antigens by infected and putative resistant individuals living in an endemic area

Abstract: The isotypic patterns of antibodies against Schistosoma mansoni antigenic preparations from eggs (SEA), adult worms (SWAP) and cercariae (CERC) have been studied in sera from two groups of individuals living in an area endemic for S. mansoni. One of the groups was comprised of individuals diagnosed as having S. mansoni infections based on their patency, i.e. those passing eggs in their faeces (patent infections, PI). The other group has been consider 'putatively resistant' due to their residence in an endemic area, their documented exposure to positive transmission sites, and their repeated negativity upon stool examinations (endemic normals, EN). There are strong specific responses of IgG1, IgG4 and IgM, particularly to SEA and CERC, by both groups. The reactivities of all isotypes were lower to SWAP. The responses of IgG4, IgM and IgE anti-CERC in EN and PI are higher than those found in normal individuals from outside endemic areas. In general, EN individuals express a relative higher level of anti-STEG IgE as compared to IgG4. On the other hand the pool of sera from PI showed the opposite pattern of higher IgG4 as compared to IgE. Several correlations are seen between isotypic responses to SEA, SWAP and CERC based on comparisons to the anti-SWAP IgE responses of the individuals in the two groups. These comparisons indicate the presence of distinct immunologic differences between individuals in the PI and the EN groups.