Domestic Rhodnius ecuadoriensis (Hemiptera, Reduviidae) infestation in Northern Peru: a comparative trial of detection methods during a six-month follow-up

Two passive methods in the assessment of intradomiciliary infestation by Rhodnius ecuadoriensis were tested: (i) the Gomes Nuñez sensor box (GN), (ii) sheets of white typing paper and (iii) one active timed manual method. The study was carried out in the Alto Chicama River Valley, Province of Gran Chimú, Department of La Libertad. The study design consisted of an initial searching of triatomines inside of the domestic environment by the manual capture active procedure (man/hour) covering all the studied houses. Then, matched pairs of GN boxes and paper sheets were simultaneously installed in the bedrooms of 207 households distributed in 19 localities. A comparative prospective trial of these passive detection devices were monitored at 2, 4 and, finally 6 months follow-up. Parasitological Trypanosoma rangeli and/or T. cruzi infections were investigated in two houses with high level of infestation by R. ecuadoriensis. 16.9% of the 207 households investigated by an initial active manual method were infested with R. ecuadoriensis. The proportion of infested houses fluctuated from 6.2 to 55.5% amongst the 19 localities investigated. T. rangeli natural infection was detected in R. ecuadoriensis specimens collected in two households. Parasite rates in the bugs ranged from 16.6 to 21.7% respectively. The most striking fact was an average rate of salivary gland infection ranging from 7.4 to 8.3%. At the end of the sixth month period, a cumulative incidence of 31.4% of positive GN boxes against 15.9% for paper sheets was recorded. All three methods combined detected domestic infestation in 129 (62.3%) of the 207 houses studied in the 19 localities. The range of houses infested varies from 6.7% to 92.9%. In areas with low bug density infestation rates, the methodology experienced in our studies, seems to be the best choice for investigations on domestic R. ecuadoriensis populations.

Detection of Trypanosoma cruzi and Trypanosoma rangeli infection in triatomine vectors by amplification of the histone H2A/SIRE and the sno-RNA-C11 genes

Trypanosoma rangeli is non pathogenic for humans but of important medical and epidemiological interest because it shares vertebrate hosts, insect vectors, reservoirs and geographic areas with T. cruzi, the etiological agent of Chagas disease. Therefore, in this work, we set up two PCR reactions, TcH2AF/R and TrFR2, to distinguish T. cruzi from T. rangeli in mixed infections of vectors based on amplification of the histone H2A/SIRE and the small nucleolar RNA Cl1 genes, respectively. Both PCRs were able to appropriately detect all T. cruzi or T. rangeli experimentally infected-triatomines, as well as the S35/S36 PCR which amplifies the variable region of minicircle kDNA of T. cruzi. In mixed infections, whereas T. cruzi DNA was amplified in 100% of samples with TcH2AF/R and S35/S36 PCRs, T. rangeli was detected in 71% with TrF/R2 and in 6% with S35/S36. In a group of Rhodnius colombiensis collected from Coyaima (Colombia), T. cruzi was identified in 100% with both PCRs and T. rangeli in 14% with TrF/R2 and 10% with S35/S36 PCR. These results show that TcH2AF/R and TrF/R2 PCRs which are capable of recognizing all T. cruzi and T. rangeli strains and lineages could be useful for diagnosis as well as for epidemiological field studies of T. cruzi and T. rangeli vector infections.

Leishmanicidal activity of Echinaster (Othilia) echinophorus crude extract

In this study, a methanolic extract from Echinaster (Othilia) echinophorus was evaluated for activity against Leishmania amazonensis. The extract showed activity against the promastigote and amastigote forms with IC50 values of 62.9 and 37.5 μg.mL-1 respectively. This extract showed a moderate toxicity on macrophages from BALB/c mice. A dose of 100 mg/kg/day was effective when administered during 15 days by intraperitoneal route to BALB/c mice infected experimentally.

In vitro antimalarial activity and cytotoxicity of some selected cuban medicinal plants

Terrestrial plants have been demonstrated to be sources of antimalarial compounds. In Cuba, little is known about antimalarial potentials of plant species used as medicinals. For that reason, we evaluated the antimalarial activity of 14 plant species used in Cuba as antimalarial, antipyretic and/or antiparasitic. Hydroalcoholic extracts were prepared and tested in vitro for the antimalarial activity against Plasmodium falciparum Ghana strain and over human cell line MRC-5 to determine cytotoxicity. Parasite multiplication was determined microscopically by the direct count of Giemsa stained parasites. A colorimetric assay was used to quantify cytotoxicity. Nine extracts showed IC50 values lower than 100 µg/mL against P. falciparum, four extracts were classified as marginally active (SI < 4), one as partially active (Parthenium hysterophorus) exhibiting SI equal to 6.2 and two extracts as active (Bambusa vulgaris and Punica granatum), showing SI > 10. B. vulgaris showed the most potent and specific antiplasmodial action (IC50 = 4.7 µg/mL, SI = 28.9). Phytochemical characterization of active extracts confirmed the presence of triterpenoids in B. vulgaris and polar compounds with phenol free groups and fluorescent metabolites in both extracts as major phytocompounds, by thin layer chromatography. In conclusion, antimalarial use of B. vulgaris and P. hysterophorus was validated. B. vulgaris and P. granatum extracts were selected for follow-up because of their strong antimalarial activity.

Hidatidose policística: relato de dois casos procedentes de Sena Madureira, Acre, na Amazônia brasileira

Dois casos de hidatidose policística (HP) são relatados, oriundos do mesmo município da região amazônica brasileira (Sena Madureira, Acre). Ambos tiveram a mesma apresentação e evolução clínica ao longo de dois anos de acompanhamento. Inicialmente os pacientes queixaram-se de dor abdominal no andar superior ou no hipocôndrio direito e apresentaram icterícia obstrutiva, febre, aumento de volume abdominal e emagrecimento. Por exame de imagem, além de esplenomegalia, cistos múltiplos e coalescentes foram detectados no fígado. Amostras de soro foram reagentes por contraimunoeletroforese. O tratamento com albendazol resultou em melhora parcial, com alívio sintomático e redução no tamanho das lesões. Este relato reforça a importância de estudos clínico-epidemiológicos da hidatidose policística na região amazônica brasileira, especialmente no município de Sena Madureira, onde outros pacientes com HP podem estar sem diagnóstico.

A PESCA ARTESANAL NO BAIXO AMAZONAS: ANÁLISE MULTIVARIADA DA CAPTURA POR ESPÉCIE.

Dados sobre esforço e captura por espécie correspondentes à produção pesqueira desembarcada no porto de Santarém, no ano de 1993, foram submetidos a duas técnicas de análise multivariada: uma análise de fatores segundo o método de componentes principais e outra de co-variância conforme o modelo linear geral (GLM). Os resultados indicam que a atividade pesqueira na região está influenciada pelas características dos ciclos de vida das espécies-alvo, pelo ciclo hidrológico e condição climáticas de sistema, e ainda pelas preferências culturais e interesses econômicos do mercado consumidor. Os resultados indicam o direcionamento da atividade pesqueira para determinados grupos de espécies, e as diferentes variáveis incluídas no modelo permitiram uma explicação aproximada dos padrões desse direcionamento. Esses padrões são: (a) pesca de grandes bagres, alvo de pesca para a exportação (FATOR 1); (b) pesca de entre-safra do mapará (Hypophthalmusspp.) e da pescada (Plagioscionspp.), realizada nos lagos com um componente para exportação e outro para o consumo local (FATOR4); (c) pesca de peixes de escamas de hábitos sedentários e/ou migratórios, alvo da pesca comercial de pequena escala e de importância no mercado local (FATOR2, FATOR3 e FATOR5), que inclui pescarias importantes como a do tambaqui (Colossoma macropomum)e do pirarucu(Arapaima gigas)nos lagos, ou a do jaraqui (Semaprochilodusspp.) e pacu (Mylossomaspp. e Metynnisspp.) nos rios.

CONSUMO DE PESCADO E OUTROS ALIMENTOS PELA POPULAÇÃO RIBEIRINHA DO LAGO GRANDE DE MONTE ALEGRE, PA - BRASIL.

O presente artigo apresenta resultados sobre o consumo de pescado e outros alimentos pela população ribeirinha do Lago Grande de Monte Alegre, no Estado do Pará, Brasil. Os dados foram coletados mensalmente, por um período de dois anos juntos a 35 famílias de 17 comunidades, que praticam a pesca com fins comerciais e de subsistência, bem como as famílias que nào pescam. O consumo médio de pescado foi de 369 g/capita/dia, complementado com 6,lg/capita/dia de farinha de peixe (piracuí). As espécies mais consumidas foram: curimatá (Prochilodus nigricans) e acarí-bodó (Liposarcus partialis). Em média, as famílias tiveram alguma refeição constituída de pescado em 6 dias de cada semana. Extrapolando para toda a população do Lago, o consumo diário de pescado é pouco mais de 3 t, chegando a 1.114 t/ano.

Dinâmica populacional do Surubim-tigre, Pseudoplatystoma Tigrinum (Valenciennes, 1840) no médio Amazonas (Siluriformes, Pimelodidae)

Dados de comprimento e de captura e esforço da pesca do surubim-tigre (Pseudoplatystoma tigrinum) obtidos durante o período de 1993 a 1996, no Médio Amazonas, foram utilizados para descrever as pescarias e estimar as taxas de crescimento e mortalidade da espécie. Os parâmetros populacionais médios estimados foram Loo =180,0 cm (comprimento total), Woo = 56,56 kg, k = 0,29 ano-1, C = 0,9; WP = Novembro, M = 0,47 ano-1, Z = l ,42 ano-1, F = 0,95 ano-1 e Lc = 87,0 cm. A análise do rendimento por recruta mostra que o estoque está sendo explorado em seu limite de sustentabilidade.

Biologia reprodutiva do Tambaqui, Colossoma macropomum Cuvier, 1818 (Teleostei, Serrasalmidae), no baixo Amazonas, Brasil

Analisaram-se aspectos da biologia reprodutiva do tambaqui (Colossoma macropomum) na região do Baixo Amazonas. Foram coletados 1232 exemplares entre outubro de 1994 e fevereiro de 1996, nos mercados e frigoríficos de Santarém no Estado do Pará. Indivíduos entre 20 e 120 cm foram pesados, medidos e observados o sexo e o estágio de maturidade. O tipo de desova e a fecundidade foram determinados através da análise dos ovócitos intraovarianos de 10 fêmeas maduras. Colossoma macropomum possui desova total. Existem variações macro e microscópicas cíclicas dos ovários associadas ao período hidrológico. A desova coincidiu com o início do período das chuvas. A proporção sexual varia com o tamanho dos peixes. A relação comprimento/peso indica diferenças nas estratégias de crescimento para ambos os sexos. O menor macho sexualmente maduro mediu 62 cm e o maior 95 cm, no caso das fêmeas, 70 cm e 112 cm respectivamente. A fecundidade média absoluta calculada para o tambaqui foi de 1.007.349 ovócitos (s = 67.279). Existe uma relação linear entre a fecundidade (F) e o peso total (W1) sendo a equação F = 885347 + 9,16 W1.

Contribution to the study of Himatanthus sucuuba: latex macromolecule, microelements and carbohydrates

The polymeric material in the latex of Himatanthus sucuuba (Spruce) Woodson was identified by spectroscopic methods as cis-polyisoprene (Mn = 192; Mw = 571; Mw/ Mn = 2.97). ICP-MS analysis of microelements in the aqueous phase showed the most abundant to be Ca (354 μg/g) and Mg (250 μg/g). Carbohydrate analysis of the aqueous phase by HPLC-PAD showed arabinose, glucose, xylose, rhamnose and galactose to be the predominant saccharides.

Associations, causation and model in psychiatry

This paper discusses models, associations and causation in psychiatry. The different types of association (linear, positive, negative, exponential, partial, U shaped relationship, hidden and spurious) between variables involved in mental disorders are presented as well as the use of multiple regression analysis to disentangle interrelatedness amongst multiple variables. A useful model should have internal consistency, external validity and predictive power; be dynamic in order to accommodate new sound knowledge; and should fit facts rather than they other way around. It is argued that whilst models are theoretical constructs they also convey a style of reasoning and can change clinical practice. Cause and effect are complex phenomena in that the same cause can yield different effects. Conversely, the same effect can have a different range of causes. In mental disorders and human behaviour there is always a chain of events initiated by the indirect and remote cause; followed by intermediate causes; and finally the direct and more immediate cause. Causes of mental disorders are grouped as those: (i) which are necessary and sufficient; (ii) which are necessary but not sufficient; and (iii) which are neither necessary nor sufficient, but when present increase the risk for mental disorders.

A comparative analysis of primary stenting and optimal balloon coronary angioplasty in acute myocardial infarction. Six month results from the STENT PAMI trial

OBJECTIVE: To compare the outcome of balloon PTCA with final coronary stenosis diameter (SD) <=30%, with elective coronary stenting. METHODS: We performed a comparative analysis of the 6 month outcomes in patients treated with primary stenting and those who obtained an optimal balloon PTCA result treated during the first 12 hours of AMI onset included in the STENT PAMI randomized trial. RESULTS: The results were analysed into 3 groups: primary stenting (441 patients, SD=22±6%), optimal PTCA (245 patients), and nonoptimal PTCA (182 patients, SD= 37±5%). At the end of the 6 months primary stent group presented with the lowest restenosis(23 vs. 31 vs. 45%, p=0.001, respectively). Ischemia-driven target vessel revascularization rate (TVR) (7 vs. 15.5 vs. 19%, p=0.001, respectively). CONCLUSION: At the 6 month follow-up, primary stenting offered the lowest restenosis and ischemia-driven TVR rates. Compared to optimal balloon PTCA. Nonoptimal primary balloon PTCA pts (SD=31-50%), had the worst late angiographic outcomes and should be treated more actively with coronary stent implantation.

One-year follow-up after primary coronary intervention for acute myocardial infarction in diabetic patients: a substudy of the STENT PAMI trial

OBJECTIVE - This analysis was undertaken to determine the composite incidence of cumulative adverse events (death, reinfarction, disabling stroke, and target vessel revascularization) at the end of the first year after acute myocardial infarction, in diabetic patients who underwent coronary stenting or primary coronary balloon angioplasty. METHODS - From the STENT PAMI trial, we analyzed the 6-month angiographic and 1-year clinical outcomes of 135 diabetic (112, noninsulin dependent) patients who underwent the randomization process of the trial and compared them with 758 nondiabetic patients. RESULTS - Coronary stenting did not significantly reduce the primary composite clinical end point when compared with PTCA (20 vs. 30%, p=0.2). A significant benefit from stenting was observed in patients with noninsulin dependent diabetes, with a trend toward a lesser need for new revascularization procedures (10 vs. 21%, p<.001), with a significant reduction in the primary composite clinical end point at 1 year (12 vs. 28%, p=. 04). At 6 months, the restenosis rate were significantly reduced only in nondiabetic patients (18 vs. 33%, p<. 001). Diabetic patients had the same restenosis rate (38%) either with stenting or balloon PTCA. CONCLUSIONS - Coronary Stenting in diabetics noninsulin dependent offered a significant reduction in the composite incidence of major clinical adverse events compared with balloon PTCA.

Vector electrocardiographic alterations after percutaneous septal ablation in obstructive hypertrophic cardiomyopathy: possible anatomic causes

OBJECTIVE: Analyze the dromotropic disturbances (vector-electrocardiographic), and the possible anatomic causes, provoked by selective alcohol injection in the septal branch, for percutaneous treatment, of obstructive hypertrophic cardiomyopathy. METHODS: Ten patients with a mean age of 52.7 years underwent percutaneous septal ablation (PTSA) from october 1998; all in functional class III/IV). Twelve-lead electrocardiogram was performed prior to and during PTSA, and later electrocardiogram and vectorcardiogram according to Frank's method. The patients were followed up for 32 months. RESULTS: On electrocardiogram (ECG) prior to PTSA all patients had sinus rhythm and left atrial enlargement, 8 left ventricular hypertrophy of systolic pattern. On ECG immediately after PTSA, 8 had complete right bundle-branch block; 1 transient total atrioventricular block; 1 alternating transient bundle-branch block either right or hemiblock. On late ECG 8 had complete right bundle-branch block confirmed by vectorcardiogram, type 1 or Grishman. CONCLUSION: Septal fibrosis following alcohol injection caused a predominance of complete right bundle-branch block, different from surgery of myotomy/myectomy.