Predictors of Trypanosoma cruzi PCR positivity in patients with chronic Chagas disease

BACKGROUND A positive Trypanosoma cruzi polymerase chain reaction (PCR) is associated with a worse prognosis in patients with chronic Chagas disease (CD). OBJECTIVES To study the association of clinical, electrocardiographic, and echocardiographic characteristics and biomarker blood levels with positive T. cruzi PCR in chronic CD. METHODS This is a single-centre observational cross-sectional study. Positive T. cruzi PCR association with clinical, electrocardiographic, and echocardiographic characteristics, and biomarker blood levels were studied by logistic regression analysis. p values < 0.05 were considered significant. FINDINGS Among 333 patients with chronic CD (56.4% men; 62 ± 10 years), T. cruzi PCR was positive in 41.1%. Stepwise multivariate logistic regression showed an independent association between positive T. cruzi PCR and diabetes mellitus {odds ratio (OR) 0.53 [95% confidence interval (CI) 0.30-0.93]; p = 0.03}, right bundle branch block [OR 1.78 (95% CI 1.09-2.89); p = 0.02], and history of trypanocidal treatment [OR 0.13 (95% CI 0.04-0.38); p = 0.0002]. Among patients with a history of trypanocidal treatment (n = 39), only four (10%) patients had a positive T. cruzi PCR. MAIN CONCLUSIONS Among several studied parameters, only diabetes mellitus, right bundle branch block, and history of trypanocidal treatment showed an independent association with positive T. cruzi PCR. History of trypanocidal treatment was a strong protective factor against a positive T. cruzi PCR.

Primera evidencia de Chlamydia psittaci en huron sable (Mustella putorios furo) en Venezuela / First evidence of Chlamydia psittaci in the sable ferret (Mustella putorios furo) in Venezuela

RESUMEN Chlamydia psittaci (Cp) es una bacteria intracelular obligada transmitida a través de aerosoles derivados de secreciones nasales y ópticas, tejidos, heces y plumas. Comúnmente es identificada en aves, sin embargo, han emergido genotipos capaces de infectar nuevos reservorios mamíferos. Por ello, se buscó ADN de Cp en muestras de cinco individuos de Mustella putorios furo y un hisopado cloacal de un individuo de Colinus cristatus en cautiverio en Venezuela a través de la PCR-anidada, amplificando un segmento del gen 16S ADNr. Se demostró la presencia de Cp en un Colinus cristatus con signos de clamidiosis y en cuatro Mustella putorios furo sin signos clínicos de clamidiosis. Se indica un posible nuevo reservorio para Cp, donde el contacto con productos de excreción de Colinus cristatus con manifestaciones clínicas de clamidiosis, hacinamiento, inadecuada ventilación, contacto con productos de excreción de Psittaciformes y condiciones sanitarias deficientes favoreció la infección por Cp. Se desconoce el total de reservorios de Cp, por ello la notificación de los aislados permite el entendimiento, distribución y diversidad de agentes clamidiales en fauna silvestre y en cautiverio.

ABSTRACT Chlamydia psittaci (Cp) is an obligate intracellular bacterium, transmitted through aerosols from nasal and optic secretions, tissues, feces, and feathers. Although commonly identified in birds, genotypes have emerged that can infect new mammalian reservoirs. Therefore, of rectal swabs samples of five Mustella putorios furo individuals and a cloacal swab sample of Colinus cristatus in captivity, in Venezuela, were tested for Cp, using the nested PCR amplifying a segment of the 16S rDNA gene. The presence of Cp was found in four asymptomatic Mustela putorios furo and one symptomatic Colinus cristatus for avian chlamydiosis, indicating a new potential reservoir for Cp. The contact with excretions of infected Colinus cristatus and Psittaciformes, as well as overcrowding, inadequate ventilation, and inadequate sanitary conditions can favor Cp infection. The total number of Cp reservoirs is unknown; therefore, the noting and molecular characterization of isolates enable the understanding, distribution, and diversity of chlamydial agents in wildlife and animals in captivity.

Tadalafil: protective action against the development of multiple organ failure syndrome

Abstract Introduction: Multiple organ failure syndrome (MOFS) is a pathology associated to unspecified and severe trauma, characterized by elevated morbidity and mortality. The complex inflammatory MOFS-related reactions generate important ischemia-reperfusion responses in the induction of this syndrome. Nitric oxide elevation, through the activation of cyclic guanosine monophosphate (cGMP), has the potential of counteracting the typical systemic vasoconstriction, and platelet-induced hypercoagulation. Tadalafil would possibly act protectively by reducing cGMP degradation with consequent diffuse vasodilatation, besides reduction of platelet-induced hypercoagulation, thus, preventing multiple organ failure syndrome development. Methods: The experimental protocol was previously approved by an institution animal research committee. Experimental MOFS was induced through the stereotaxic micro-neurosurgical bilateral anterior hypothalamic lesions model. Groups of 10 Wistar rats were divided into: a) Non-operated control; b) Operated control group; c) 2 hours after tadalafil-treated operated group; d) 4 hours after tadalafil-treated operated group; e) 8 hours after post-treated operated group. The animals were sacrificed 24 hours after the neurosurgical procedure and submitted to histopathologic examination of five organs: brain, lungs, stomach, kidneys, and liver. Results: The electrolytic hypothalamic lesions resulted in a full picture of MOFS with disseminated multiple-organs lesions, provoked primarily by diffusely spread micro-thrombi. The treatment with tadalafil 2 hours after the micro-neurosurgical lesions reduced the experimental MOFS lesions development, in a highly significant level (P<0.01) of 58.75%. The treatment with tadalafil, 4 hours after the micro-neurosurgically-induced MOFS lesions, also reduced in 49.71%, in a highly significant level (P<0.01). Finally, the treatment with tadalafil 8 hours after the neurosurgical procedure resulted in a statistically significant reduction of 30.50% (P<0.05) of the experimentally-induced MOFS gravity scores. Conclusion: The phosphodiesterase 5 inhibitor, tadalafil, in the doses and timing utilized, showed to protect against the experimentally-induced MOFS.

Myricitrin as the main constituent of two species of Myrcia.

Myricitrin was isolated as the major constituent from Myrcia splendens (2 g %) and Myrcia palustris (0.5g %) of their fractions soluble in ethyl acetate. The presence of this compound was confirmed by chromatographic analyses using HPLC-DAD. The antioxidant activity was measured using reducing power in relation to the reduction of iron (III) to iron (II) ions and DPPH radical scavenging assay. The ethyl acetate and butanol fractions showed the highest antioxidant activity for both species. In relation to the ability of the sample to scavenge DPPH radicals the EC50 values were 8.44 and 9.35 μg/ mL for M. splendens and 17.83 and 15.34 μg/ mL for M. palustris for the ethyl acetate and butanol fractions, respectively. The antioxidant activity may be related to the myricitrin in these extracts that showed an EC50 = 13.93 μg/mL.

Chemical constituents and evaluation of the toxic and antioxidant activities of Averrhoa carambola leaves

The liquid-liquid partitioning of a crude hydroalcoholic extract of Averrhoa carambola L., Oxalidaceae, leaves led to the isolation of a sterol and three flavone C-glycosides. From the n-hexane fraction β-sitosterol was isolated and from the ethyl acetate fraction apigenin-6-C-β-L-fucopyranoside (1) and apigenin6-C-(2"-O-α-L-rhamnopyranosyl)-β-L-fucopyranoside (2) were obtained. Apigenin6-C-(2"-O-α-L-rhamnopyranosyl)-β-D-glucopyranoside (3) was isolated from the n-butanol fraction. Compound 3 is new, while 1 and 2 have been previously isolated from A. carambola. The antioxidant activity was measured using the DPPH radical scavenging assay and reducing power of iron (III) to iron (II) ions. The ethyl acetate and n-butanol fractions showed the most antioxidant activity. As evaluated by ability of the sample to scavenge DPPH the IC50 values were 90.92 and 124.48 µg/ mL, respectively. In the assay of reducing power these fractions presented 135.64 and 125.12 of ascorbic acid equivalents, respectively. The antioxidant activity exhibited a significant relationship with the phenolic content (r² = 0.997), but a poor relationship with the flavonoids content (r² = 0.424). The n-hexane fraction was the only fraction to present good toxicity using A. salina with LC50 800.2 µg/mL.

Clinical features and surgical outcome of patients with indolent brain tumors and epilepsy

INTRODUCTION: In this study the authors review the outcomes of 22 patients with medically refractory epilepsy and slow growth brain tumors. OBJECTIVES: Evaluate the clinical, electrophysiological, operative, and histopathological features. PATIENTS AND RESULTS: The majority of the tumors were located in the temporal lobe (n = 20) and involved the cortical gray matter. The most frequent tumors were gangliogliomas (n = 9), astrocytomas grade I and II (n = 6), dysembryoplastic neuroepithelial tumors (n = 5) and ganglioneuroma (n = 2). The biological behavior of the tumors was strikingly indolent, as indicated by a long preoperative history of chronic seizures (mean, 14 years). Mean follow-up time after resection was 27 months, and according to EngelÆs classification, 85 percent were seizure-free, 10 percent showed a reduction of seizure frequency of at least 90 percent, and 5 percent had reduction in seizure frequency at least 75 percent. CONCLUSION: The data indicate that neoplasms associated with pharmacoresistent epilepsy constitute a distinct clinicopathological group of tumors that arise in young patients, involve the cortex, and exhibit indolent biological behavior for many years. Complete surgical removal of these tumors, including the epileptogenic area, can achieve excellent seizure control.

INTRODUÇÃO: Neste estudo os autores avaliaram retrospectivamente 22 pacientes tratados cirurgicamente com diagnóstico de epilepsia refratária e tumor cerebral de crescimento lento. OBJETIVOS: Avaliar os aspectos clínicos, eletrofisiológicos, cirúrgicos e histopatológicos. PACIENTES E RESULTADOS: A maioria dos tumores estava localizada no lobo temporal (n = 20) com envolvimento da substância cinzenta. Ganglioglioma foi o tumor mais frequente (n = 9), seguido do astrocitoma grau I e II OMS (n = 6), tumor neuroepitelial disembrioplástico (DNET) (n = 5) e ganglioneuroma (n = 2). O comportamento biológico dos tumores foi estritamente indolente como indicado pela longa história pré-operatória de (média, 14 anos). O tempo de acompanhamento pós-operatório médio foi de 27 meses e de acordo com a Classificacão de Engel, 85 por cento ficaram sem crises (Classe I), 10 por cento obtiveram redução maior de 90 por cento das crises (Classe II), e 5 por cento tiveram redução menor que 75 por cento (Classe III). CONCLUSÃO: Os dados indicam que neoplasias associadas à epilepsia crônica refratária constituem um grupo de tumores com características clinico-patológicas distintas que se iniciam em pacientes jovens, envolvem o córtex e apresentam comportamento biológico indolente. A ressecção cirúrgica completa destes tumores, incluindo a zona epileptogênica, levou ao controle total das crises na maior parte dos casos estudados.

Alternância elétrica da onda T: bases eletrofisiológicas e aplicações clínicas baseadas em evidências / T wave electrical alternans: electrophysiological basis and clinical application based on evidence

O presente estudo faz uma revisão dos conceitos de alternância cardíaca, com enfoque na alternância elétrica em microvoltagem da amplitude da onda T (MAOT). Apresenta uma perspectiva histórica e faz uma revisão dos recentes avanços no campo da eletrofisiologia cardíaca, com o objetivo de elucidar não somente os mecanismos responsáveis pela manifestação da MAOT no eletrocardiograma de superfície, mas também apresentar evidências experimentais in vitro e in vivo que associam a MAOT às arritmias cardíacas por fenômeno de reentrada. Finalmente, faz uma revisão dos estudos clínicos prospectivos que identificam a MAOT como preditor independente de arritmias cardíacas potencialmente fatais, e propõe diretrizes baseadas em evidências clínicas para a utilização da MAOT na avaliação de risco de arritmias cardíacas em indivíduos com doença estrutural cardíaca.

Antiarrítmicos e arritmogênese / Antiarrhythmic drugs and arrhythmogenesis

A capacidade de drogas produzir arritmias cardíacas ou agravar as preexistentes denomina-se arritmogênese ou pró-arritmia.Näo existe consenso quanto aos critérios que definam esse fenômeno, o que torna difícil a análise de sua incidência.O risco de desenvolvimento de pró-arritmia depende principalmente das características clínicas do paciente tratado e do tipo de antiarrítmico utilizado.A decisäo de se iniciar o tratamento farmacológico de uma arritmia cardíaca deve ser tomada sempre levando-se em conta seu potencial arritmogênico.A "torsades de pointes", uma taquicardia ventricular polimórfica associada ao aumento do intervalo QT induzido pela droga, é uma das apresentações eletrocardiográficas mais reconhecidas.Importante marco no tratamento farmacológico das arritmias ventriculares foi o estudo CAST, onde ficou evidente a maior mortalidade relacionada ao uso de drogas antiarrítmicas da classe I.Também no tratamento da fibrilaçäo atrial, existem evidências de aumento da mortalidade nos pacientes tratados com a quinidina.O tratamento da pró-arritmia baseia-se principalmente na retirada do antiarrítmico, correçäo dos fatores precipitantes e reversäo da arritmia provocada.

Distribuiçäo pilosa em mulheres jovens: normal ou hirsutismo / Pilosus distribution in young women: normal or hirsutism

Tentamos aqui estabelecer um parâmetro objetivo para diferenciar crescimento piloso normal de hirsutismo em mulheres jovens brancas brasileiras e, baseado neste trabalho, passamos a definir como hirsutas as mulheres que apresentaram ++ ou mais cruzes de pêlos em três ou mais das regiöes analisadas. Discutimos também dados interessantes de uso em prática ambulatorial diária