RESUMO
A stereoselective total synthesis of (-)-cryptocaryol A (1) is described. Key features of the 17-step route include the use of three boron-mediated aldol reaction-reduction sequences to control all stereocenters and an Ando modification of the Horner-Wadsworth-Emmons olefination that permitted the installation of the Z double bond of the α-pyrone ring.
Assuntos
Pironas/síntese química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Ésteres/síntese química , Ésteres/química , Espectroscopia de Prótons por Ressonância Magnética , Pironas/química , EstereoisomerismoRESUMO
BACKGROUND AND OBJECTIVE: Stress and anxiety have been associated with chronic periodontitis, but few studies examining the effects of psychotropic drugs on periodontal health have been performed. Therefore, we aimed to investigate the effects of diazepam on the progression of periodontitis in chronically stressed rats. MATERIAL AND METHODS: Fourteen Wistar rats were submitted to ligature-induced periodontal disease and were divided into four groups . Two groups were not stressed, whereas two groups were submitted to a conditioned fear stress paradigm for 38 d. Daily diazepam treatment (2 mg/kg, orally) was administered to one unstressed group and to one group submitted to a conditioned fear stress paradigm from day 2 to the day 39, at which point the rats were submitted to an open field test and were killed on day 40. Brains and mandibles were removed for histological and immunohistochemical analyses. RESULTS: Animals exposed to conditioned fear stress presented an increase in freezing behavior, a decrease in locomotor activity, enhanced alveolar bone loss and higher levels of hippocampal interleukin-1beta (IL-1ß) and interleukin-6 (IL-6), compared with the control group. Diazepam, at the dose used in the current study, had no effect on freezing behavior but reversed the decrease in locomotor activity provoked by stress. Additionally, the treatment reduced the levels of hippocampal IL-1ß and IL-6 and alveolar bone loss in Wistar rats. Neither conditioned fear stress nor diazepam treatment had an effect on periodontal IL-1ß or IL-6 levels in animals. CONCLUSION: Our results suggest that diazepam treatment reduces bone loss in rats submitted to conditioned fear stress. In addition, diazepam treatment led to decreased IL-1ß and IL-6 levels in the hippocampus.
Assuntos
Perda do Osso Alveolar/prevenção & controle , Ansiolíticos/uso terapêutico , Diazepam/uso terapêutico , Medo/fisiologia , Hipocampo/metabolismo , Interleucina-1beta/análise , Interleucina-6/análise , Perda do Osso Alveolar/metabolismo , Animais , Ansiolíticos/administração & dosagem , Condicionamento Operante , Diazepam/administração & dosagem , Progressão da Doença , Medo/psicologia , Reação de Congelamento Cataléptica/fisiologia , Hipocampo/patologia , Locomoção/fisiologia , Masculino , Ligamento Periodontal/metabolismo , Ligamento Periodontal/patologia , Periodontite/prevenção & controle , Periodontite/psicologia , Ratos , Ratos Wistar , Estresse Psicológico/metabolismo , Estresse Psicológico/psicologiaRESUMO
AIM: To identify and quantify mast cell (MC), vascular endothelial growth factor (VEGF) expression and microvessel density (MVD) in human periapical cysts and granulomas. METHODOLOGY: Archived samples of cysts (n = 40) and granulomas (n = 28) were sectioned and stained with toluidine blue. MCs were identified and counted. Immunohistochemical reactions were employed to evaluate the tissue expression of VEGF and vessels. MVD was estimated by determining the areas of tissue labelled with CD31 antibody. The data were analysed using the Mann-Whitney test (P < 0.05). RESULTS: MCs were observed in the peripheral regions of both lesion types, whilst VEGF and MVD were distributed in the stroma. The presence of MCs was higher in cysts than in granulomas (P < 0.05). VEGF and MVD expression were similar in these lesions. CONCLUSIONS: The highest number of MCs was observed in cysts. Moreover, the identification of VEGF and MVD was consistent with the immune mechanisms involved in the lesions.
Assuntos
Mastócitos/patologia , Microvasos/patologia , Granuloma Periapical/patologia , Cisto Radicular/patologia , Fator A de Crescimento do Endotélio Vascular/análise , Adulto , Capilares/patologia , Contagem de Células , Corantes , Tecido Conjuntivo/patologia , Estudos Transversais , Epitélio/patologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Cloreto de TolônioRESUMO
A prospective clinical and microbiological surveillance study was conducted during a 26-month period to evaluate consecutive malignancy or post-bone marrow transplant patients with positive blood cultures. The study included 859 episodes of bloodstream infection (BSI) in 719 patients. There were 6.9 BSI episodes/1000 patient-days. Overall mortality was 25%. The median age of patients was 43 years, with 71% of episodes occurring in patients aged > 18 years. Patients with underlying haematology malignancies accounted for 38.2% of the episodes. An indwelling central vein catheter was present in 61% of episodes. BSI origin was unknown in 27% of episodes, associated with other sites in 49.6%, and catheter-related in 23.4%. There were 638 concomitant infection sites, of which the most common were pulmonary (28.4%), urinary tract (14.8%), and non-surgical skin or soft tissue (9.7%). In total, 1039 microorganisms were isolated within 48 h of the first blood culture, of which Gram-negative bacilli accounted for 56%. Among Klebsiella pneumoniae and Escherichia coli isolates, 37.8% and 8.9%, respectively, produced extended-spectrum beta-lactamases. High rates of ceftazidime resistance were detected among Acinetobacter spp. (40%) and Enterobacter spp. (51.2%). E. coli and K. pneumoniae were isolated frequently from haematology patients, and Enterobacter spp. from solid tumour patients. E. coli, K. pneumoniae and Pseudomonas aeruginosa were isolated more often from neutropenic than from non-neutropenic patients. Oxacillin resistance was detected in 18.7% of Staphylococcus aureus isolates. It was concluded that continuous multidisciplinary surveillance of BSI is warranted in this high-risk group of patients in order to develop strategies for antimicrobial resistance control and treatment of infectious complications.
Assuntos
Bacteriemia/epidemiologia , Bactérias/efeitos dos fármacos , Transplante de Medula Óssea/efeitos adversos , Institutos de Câncer , Farmacorresistência Bacteriana , Neoplasias/complicações , Vigilância da População , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Bacteriemia/microbiologia , Bactérias/classificação , Bactérias/isolamento & purificação , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
The total synthesis of (+)-crocacin C is described. The convergent asymmetric synthesis relies on the use of a regio- and diastereoselective epoxidation of an allylic alcohol with m-CPBA followed by epoxide opening with Me(2)CuCNLi(2) and a Stille cross-coupling between E-vinyl stannane 5 and E-vinyl iodide 6 to establish the (E,E)-dienamide moiety. [structure: see text]
Assuntos
Polienos/síntese química , Polienos/química , EstereoisomerismoRESUMO
In 6-methyl-N-(4-nitrobenzoyl)-5,6-dihydropyridin-2(1H)-one, C(13)H(12)N(2)O(4), (I), the piperidone ring is in a distorted half-chair conformation. In 8-methoxy-3-methyl-N-(4-nitrobenzoyl)-1,2,3,4,5,6,7,8-octahydroisoquinoline-1,6-dione, C(18)H(20)N(2)O(6), (II), the heterocyclic ring is in a slightly distorted half-boat conformation, while the other six-membered ring is in a distorted chair conformation. Compound (II) presents a strong intramolecular C-H...O hydrogen bond. In both (I) and (II), the molecules interact through C-H...O interactions.
Assuntos
Antagonistas de Aminoácidos Excitatórios/química , Isoquinolinas/química , Nitrocompostos/química , Piridinas/química , Quinolinas/química , Receptores de AMPA/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Cristalografia por Raios X , Antagonistas de Aminoácidos Excitatórios/síntese química , Isoquinolinas/síntese química , Estrutura Molecular , Nitrocompostos/síntese química , Piridinas/síntese química , Quinolinas/síntese química , Quinolinas/farmacologiaRESUMO
The diagnostic potential of circulating IgM and IgA antibodies against Schistosoma mansoni gut-associated antigens detected by the immunofluorescence test (IFT) on adult worm paraffin sections was evaluated comparatively to the fecal parasitological method, for epidemiological purposes in low endemic areas for schistosomiasis. Blood samples were collected on filter paper from two groups of schoolchildren living in two different localities of the municipality of Itariri (São Paulo, Brazil) with different histories and prevalences of schistosomiasis. The parasitological and serological data were compared to those obtained for another group of schoolchildren from a non-endemic area for schistosomiasis. The results showed poor sensitivity of the parasitological method in detecting individuals with low worm burden and indicate the potential of the serological method as an important tool to be incorporated into schistosomiasis control and vigilance programs for determining the real situation of schistosomiasis in low endemic areas.
Assuntos
Anticorpos Anti-Helmínticos/sangue , Fezes/parasitologia , Imunoglobulina A/sangue , Imunoglobulina M/sangue , Schistosoma mansoni/imunologia , Esquistossomose mansoni/epidemiologia , Animais , Brasil/epidemiologia , Criança , Humanos , Prevalência , Esquistossomose mansoni/sangue , Sensibilidade e Especificidade , Estudos SoroepidemiológicosRESUMO
For a period of 2 years, five follow-up measures of prevalence and incidence rates were estimated in a prospective study of S. mansoni infection in a group of schoolchildren who were living in a rural area of the Municipality of Itariri (São Paulo, Brazil), where schistosomiasis is transmitted by Biomphalaria tenagophila. Infection was determined by the examination of three Kato-Katz stool slides, and the parasitological findings were analyzed in comparison to serological data. In the five surveys, carried out at 6-month intervals (March-April and September-October), the prevalences were, respectively, 8.6, 6.8, 9.9, 5.8 and 17.2% by the Kato-Katz, and 56.5, 52.6, 60.8, 53.5 and 70.1% by the immunofluorescence test (IFT). Geometric mean egg counts were low: 57.8, 33.0, 35.6, 47.3 and 40.9 eggs per gram of feces, respectively. Of the total of 299 schoolchildren, who submitted five blood samples at 6-month intervals, one for each survey, 40% were IFT-positive throughout the study, and 22% were IFT-negative in all five surveys. Seroconversion from IFT negative to positive, indicating newly acquired S. mansoni infection, was observed more frequently in surveys carried out during March-April (after Summer holidays), than during September-October. Seasonal trends were not statistically significant for detection of S. mansoni eggs in stool. The results indicate that the use of IgM-IFT is superior to parasitological methods for detection of incidence of S. mansoni infection in areas with low worm burden.
Assuntos
Anticorpos Anti-Helmínticos/sangue , Imunoglobulina M/sangue , Schistosoma mansoni/imunologia , Esquistossomose mansoni/diagnóstico , Esquistossomose mansoni/imunologia , Adolescente , Animais , Brasil , Criança , Pré-Escolar , Fezes/parasitologia , Seguimentos , Humanos , Incidência , Contagem de Ovos de Parasitas , Prevalência , Estudos Prospectivos , População Rural , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/transmissão , Estações do Ano , Sensibilidade e EspecificidadeRESUMO
The potential of an immunofluorescence test for detection of IgM antibodies against Schistosoma mansoni gut-associated antigens (IgM-IFT) was evaluated as a tool for studying aspects related to the schistosomiasis transmission in Ribeirão Pires, in the metropolitan area of the capital of the State of São Paulo, Brazil. Children from a school with about 400 students, 6 to 18 years, were followed-up for two years. In the five surveys, carried out at 6-month intervals, from October 92 to October 94, serological (IgM-IFT) prevalence indices of 5.3%, 5.8%, 6.2%, 2.9% and 3.3% were obtained. These indices were 7 to 10 times higher than the parasitological prevalence indices of 0.5%, 0.5%, 0.7%, 0.4% and 0% determined by the Kato-Katz method. Seroconversion from IFT negative to positive was indicating possible newly acquired S. mansoni infection in three children. But confirmation of infection by fecal examination was possible in only one child. The IgM-IFT can constitute a valuable tool for the improvement of the vigilance program in low endemic areas for schistosomiasis, better characterizing the S. mansoni transmission in such areas.
Assuntos
Anticorpos Anti-Helmínticos/sangue , Inquéritos Epidemiológicos , Imunoglobulina M/sangue , Polissacarídeos/imunologia , Schistosoma mansoni/imunologia , Esquistossomose/diagnóstico , Esquistossomose/transmissão , Adolescente , Animais , Brasil/epidemiologia , Criança , Intervalos de Confiança , Feminino , Imunofluorescência , Seguimentos , Humanos , Masculino , Prevalência , Esquistossomose/epidemiologia , População UrbanaRESUMO
The detection of IgM antibodies for Schistosoma mansoni using gut-associated antigens (IgM-IFT) was compared to the parasitological Kato-Katz method for study of the transmission of schistosomiasis in an urban area in Campinas. About 400 schoolchildren whose ages ranged from 6 to 18 years, were observed for a period of two years. Blood samples on filter paper and fecal samples were collected, at intervals of six months. Serological (IgM-IFT) prevalence rates of 1.2%, 4.3%, 3.6%, 2.9% and 3.4% were obtained in five surveys carried out. S. mansoni eggs were detected in only one child out of the 225 children (0.4%) who were submitted to the Kato-Katz method (three slides for each fecal sample) in the 1st survey. Sixty eight children who submitted five blood samples, one for each survey, were found IFT negative throughout the study. No child was found to be IFT positive in all five surveys, and only four children showed IFT positive results in at least four surveys. Seroconversion from IFT negative to positive was observed from the 1st to the 2nd survey in six children, from the 2nd to the 3rd survey in three children, from the 3rd to the 4th survey in four children, and from the 4th to the 5th survey in two cases. However, confirmation of S. mansoni infection using the fecal examination was not possible in any of the cases. Also, in most of them the IFT result oscillated from negative to positive and vice versa. Our data implied that recent transmission of schistosomiasis in the study area was not possible.
Assuntos
Anticorpos Anti-Helmínticos/sangue , Imunofluorescência , Imunoglobulina M/sangue , Schistosoma mansoni/imunologia , Esquistossomose mansoni/transmissão , Adolescente , Animais , Brasil/epidemiologia , Criança , Fezes/parasitologia , Humanos , Prevalência , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/parasitologia , População UrbanaRESUMO
During the examination of a Great Egret (Casmeridus albus) when captured and taken to the Quinzinho de Barros Municipal Zoo in Sorocaba, state of Sao Paulo, seven arthropod were taken from the bird and put into ethanol at 70ºGL, and afterwards turned over to the Laboratory of Tick Morphophysiology and Pathogeny-Animal Sanity (LMPC-SA), of the Rio de Janeiro Federal Rural University. Animal's Parasite Study Department (DPA/IB/UFRRJ) where they were identified. These arthropod were then classified as belonging to the Hippoboscidae (Diptera, Pupipara) family. To make the genus and species identification possible it was necessary to prepare microscope slides for observation. The hippoboscidae were then identified as Ornithoica confluenta (Say), and sent to the Entomological Collection of the Instituto Oswaldo Cruz. This study is fit into the inter-institutional project that involves the PZMQB and the LMPC-SA/DPA/IB/UFRRJ
Assuntos
Animais , Aves/parasitologia , Dípteros/anatomia & histologia , Brasil , Ectoparasitoses , Larva , Miíase , Interações Hospedeiro-ParasitaRESUMO
Despite the success of control programmes, schistosomiasis is still a serious public health problem in the world. More than 70 countries where 200 million individuals are evaluated to be infected of a total 600 million at risk. Though there have been important local success in the control of transmission, globally the infection has increased. Economic constrains in developing countries, environmental changes associated with migration and water resources development have been blocking the progress. The main objective of schistosomiasis control is to achieve reduction of disease due to schistosomiasis. We discussed the control measures like: health education, diagnosis and chemotherapy, safe water supplies, sanitation and snail control. We emphasized the need to give priority to school-age children and the importance of integrating the measures of control into locally available systems of health care. The control of schistosomiasis is directly related to the capacity of the preventive health services of an endemic country. The strategy of control requires long-term commitment from the international to the local level.
Assuntos
Esquistossomose/prevenção & controle , Animais , HumanosRESUMO
We discuss the epidemiological patterns of schistosomiasis mansoni in areas with low transmission in Brazil. We define as areas of low endemicity those where the prevalence is less than 10%, the number Schistosoma mansoni eggs per gram of feces (epg) is less than 96, and carriers are asymptomatic. Data are from the county of Pedro de Toledo in the Ribeira Valley (São Paulo State) and were collected randomly according to the aggregate pattern of S. mansoni within the hosts. We suggest the replacement of parasitological methods by more sensitive and specific serological techniques. The main risk factor for infection is type of leisure activity. Infection is more frequent in the 10-14, 15-19, and 20-24-year age brackets. Geometric mean epg is 58.5. Intensity of infections correlates well (rs = 0.745) with prevalence. The highest index of potential contamination is in the 5-20-year age bracket (57.6%). Autochthonous cases show close association with Biomphalaria tenagophila, which has a low infection rate (2%). Prevalence, incidence, and intensity of infection patterns are similar to those of moderate and high endemic areas. Social and cultural aspects must be studied in order to obtain a global epidemiological view of schistosomiasis.
RESUMO
Two drug-resistant strains of Schistosoma mansoni were compared in this study in order to decide whether they are both mutated in the same gene with respect to drug-sensitive schistosomes. One of the two strains was isolated in the laboratory, while the other one originated from a treated uncured patient and was subsequently drug selected in the laboratory. The approach consisted in a genetic complementation test performed essentially by crossing the two strains and assessing resistance in the progeny. Since no reappearance of drug sensitivity was detected in the progeny, it was concluded that the two strains failed to complement and were therefore mutated in the same gene. This finding suggests that a single step of drug activation operates in sensitive schistosomes and is ineffective in resistant worms.
Assuntos
Hicantone/farmacologia , Mutação , Oxamniquine/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Schistosoma mansoni/genética , Animais , Resistência a Medicamentos/genética , Feminino , Teste de Complementação Genética , Humanos , Masculino , Especificidade da EspécieRESUMO
Risk factors for Schistosoma mansoni infection were identified using a 1:1 matched case-control design. The work was conducted in the municipality of Pedro de Toledo, São Paulo State, Brazil, an area where the snail host is Biomphalaria tenagophila. Information on water contact patterns, knowledge, attitudes and practices (kap), socioeconomic and sanitary conditions were obtained by mean of questionnaires. The crude odds ratio estimates and the adjusted odds ratio estimates using the logistic regression model are presented. Most of the examined individuals admitted recent water contacts (90.6% of the cases). The most frequent reason for contact was swimming, playing and fishing and the preferential site of contact was the river. According to the logistic regression technique, the main risk factors for infection were: a) water contact through swimming, playing and fishing; b) fording; c) bad hygiene. We concluded that recreational activities are the main reasons for schistosomiasis transmission in Pedro de Toledo and leisure alternatives should be offered to the local population.
Assuntos
Esquistossomose mansoni/transmissão , Animais , Biomphalaria/parasitologia , Estudos de Casos e Controles , Humanos , Higiene , Fatores de Risco , Schistosoma mansoni/fisiologia , Fatores SocioeconômicosRESUMO
The susceptibility of four isolates of Schistosoma mansoni (BH, MAP, MPR-1 and K) to four multiple doses of anti-schistosomal agents (hycanthone, niridazole, oxamniquine, and praziquantel) were evaluated in infected female Swiss albino mice. These schistosomal isolates had been maintained in the laboratory without further drug pressure for 20 to 30 generations. Multiple dosage regimens were used for each drug against each isolate of S. mansoni to generate ED50 (effective dose 50%) values. Results demonstrated that the K isolate is resistant to niridazole, the MPR-1 isolate to oxamniquine, and the MAP isolate to both hycanthone and oxamniquine. The BH isolate was susceptible to all drugs and was used as the reference isolate. All isolates were susceptible to parziquantel. The significance of the difference in response of the MPR-1 and MAP isolates is discussed. These results confirm the resistance of these isolates of S. mansoni to three schistosomicides and demonstrate that the resistance of these isolates are stable over long periods of time without exposure to drugs.
Assuntos
Schistosoma mansoni/efeitos dos fármacos , Esquistossomicidas/farmacologia , Animais , Relação Dose-Resposta a Droga , Resistência a Medicamentos , Feminino , Hicantone/farmacologia , Masculino , Camundongos , Niridazol/farmacologia , Oxamniquine/farmacologia , Praziquantel/farmacologia , Esquistossomicidas/administração & dosagemRESUMO
In the São Paulo State, Brazil, where the Biomphalaria tenagophila is the intermediate host, the Ribeira Valley is an important endemic schistosomiasis mansoni area. During last eleven years there has been intense control measures focusing on schistosomiasis. The efforts have been concentrated in the municipalities of Pedro de Toledo and Itariri. We determined the susceptibility of B. tenagophila to sympatric strain of S. mansoni, both recently isolated from Itariri field. In 1988, this strain was isolated and maintained in the experimental model: Swiss mice--sympatric B. tenagophila. The second generation of the worm was evaluated. The snail were divided in the three groups of 60 snails each. One group was exposed to 1 miracidium and other to 10. The third group was the control. The mortality and the shedding of cercariae were checked during 78 days. After that, the positive snails were observed until they ceased to shed cercariae. The exposed molluscs showed mortality rates of 23% and 31% and infection indexes were of 8% and 60% to 1 and 10 miracidia respectively. The mortality was of 22% in the control group. The periods of shedding cercariae in the two groups were 82 and 104 days. We can conclude that B. tenagophila is an effective intermediate host to the sympatric strain of S. mansoni sympatric strain.
Assuntos
Biomphalaria/parasitologia , Vetores de Doenças , Schistosoma mansoni/patogenicidade , Animais , Brasil , Interações Hospedeiro-Parasita , Larva/anatomia & histologia , Larva/patogenicidade , Camundongos , Schistosoma mansoni/anatomia & histologia , Fatores de TempoRESUMO
The objective of this study is to determine whether various hycanthone resistant strains of schistosomes which have been independently isolated are all affected in the same gene. A strain obtained from a Brazilian patient was compared with a strain of Puerto Rican origin selected in the laboratory. If the mutation conferring resistance involved two different genes, one would expect that progeny of a cross between the two strains would show complementation, i.e. it would be sensitive to the drug. We have performed such a cross and obtained F1 hybrid worms which were essentially all resistant, thus suggesting that the mutation conferring resistance in the two strains involves the same gene.
Assuntos
Genes de Helmintos , Hicantone/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Animais , Brasil , Cruzamentos Genéticos , DNA/efeitos dos fármacos , Resistência a Medicamentos/genética , Genes Recessivos , Teste de Complementação Genética , Camundongos , Oxamniquine/farmacologia , Porto Rico , Schistosoma mansoni/genética , Schistosoma mansoni/isolamento & purificação , Especificidade da EspécieRESUMO
The schistosomiasis is transmitted by Biomphalaria tenagophila in our study area (Pedro de Toledo, São Paulo, Brazil). From 1980 to 1990 epidemiological surveys in a population of 4,000 inhabitants, has shown that: prevalences by Kato-Katz (KKT), immunofluorescence (FT) and intradermal (IDT) techniques were 22.8%, 55.5% and 51.8%, respectively; intensity of infection was low, 58.5 eggs per gram of faeces (epg); there were no symptomatic cases; prevalences were higher in mates, children and rural zone; index of potential contamination was 57.5% in the age group 5 to 20 years; 2/3 of patients were autochthonous; cases were no-randomly aggregated; transmission was focal and only 0.4% of snails were infected; water contacts through recreation showed the most important odds ratio; knowledge, attitudes and practices were satisfactory. From the epidemiological findings a control programme was carried out: yearly faeces exams, chemotherapy, molluscocide, health education and sanitation. Thus, the prevalence decreased sharply to 3.3% and intensity of infection to 30.3 epg; the incidence rates ranged between 0.4% and 2.5% annually; the sanitation became better and the youngsters were the main target in prophylaxis. To improve control, immunodiagnosis has to be conducted and the involvement of the population should be increase. However, we cannot forget that re-infection, therapeutic failure, etc, could play a major role in the maintenance this residual prevalence.
Assuntos
Esquistossomose mansoni/prevenção & controle , Adolescente , Adulto , Animais , Biomphalaria/parasitologia , Brasil/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Vetores de Doenças , Feminino , Imunofluorescência , Educação em Saúde , Humanos , Incidência , Testes Intradérmicos , Masculino , Moluscocidas , Razão de Chances , Contagem de Ovos de Parasitas , Praziquantel/uso terapêutico , Prevalência , Avaliação de Programas e Projetos de Saúde , Esquistossomose mansoni/diagnóstico , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/transmissão , Poluição da Água/prevenção & controleRESUMO
In population surveys in which the Schistosoma mansoni intensity of infection is low, or in localities where the schistosomiasis control program had success, the parasitologic methods lack in sensitivity. Despite of some limitations, the immunological methods are useful to provide valuable information in such field conditions. Thus, the prevalence of schistosomiasis in untreated population can be determined by the detection of IgG or IgM antibodies, as well as the incidence by the IgA antibodies, employing mainly immunofluorescence (IF) and immunoenzymatic (ELISA), and in some extent hemagglutination (HA) or even skin test. The true prevalence and incidence of schistosomiasis can be estimated using a probabilistic model equation, since knowing before-hand the sensitivity and specificity of employed test. The sensitivity and the specificity of serologic test become higher in low aged group, under 14. The geometric mean IF titers also gives a positive correlation with the intensity of infection. Presently, there are need of serologic tests which are economic and practical in seroepidemiologic inquiries, requiring no specialized personnel to collect population blood or serum samples, and also easily interpret the test results. The reagents for such tests are desired to be stable and reproducible. Moreover, it is expected that the tests can distinguish an active infection.