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Relata-se o quadro clínico de 27 pacientes com doença de Chagas aguda, acompanhados no ambulatório da Clínica de Doenças Infecciosas e Parasitárias do Hospital das Clínicas da FM-USP no período de 1974 a 1987. As vias de transmissão envolvidas foram: vetorial em 7 casos, transfusional em 9, transplante de rim e/ou transfusional em 4, acidental em 1, via oral em 3, provável aleitamento materno em 1, congênita ou aleitamento materno em 1, congênita ou transfusional em 1. Pacientes com infecção por via vetorial eram procedentes da Bahia e Minas Gerais, tendo 6 apresentado a doença de 1974 a 1980 e um em 1987. Já os pacientes infectados por via transfusional adquiriram a doença na Grande São Paulo, 7 deles após 1983. O quadro clínico foi oligossintomático ou assintomático em 4 pacientes, sendo 3 deles imunodeprimidos por doença de base ou por medicamentos. Em outros 2 pacientes imunodeprimidos ocorreu miocardite grave com insuficiência cardíaca congestiva. O quadro clínico foi também mais grave em 5 de 6 crianças menores de dois anos de idade, qualquer que fosse a via de transmissão. A avaliação de 16 pacientes tratados na fase aguda com benzonidazol (4-10mg/kg/dia) por 30 a 60 dias mostrou falha terapêutica em 4/16 (25,0%), possível sucesso terapêutico em 9/16 (56,2%), sendo inconclusivos os resultados em 3/16 (18,8%). A reação de LMC foi concordante com o xenodiagóstico em 18 e 22 casos (agudos e na fase crônica inicial), e se negativou mais precocemente que as RSC. No seguimento pós-terapêutico, observou-se aparecimento de doença linfoproliferativa em um paciente com anemia aplástica e que recebia corticosteróide 6 anos após o emprego de benzonidazol.The authors report clinical features and therapeutic response of 24 outpatients with acute Chagas' disease, and 3 in the initial chronic phase, referred to the Clinic for Infectious and Parasitic Diseases of the FMUSP "Clínicas" Hospital between 1974 and 1987. The following transmission routes were involved: triatominae in 7 cases, blood transfusion in 9, kidney transplantation and/or blood transfusion in 4, accidental in 1, oral route in 3, probably breast feeding in 1, congenital or breast feeding in 1, and congenital or blood transfusion in 1. Six patients infected by triatominae acquired the disease between 1974 and 1980 and one in 1987. The blood transfusion infected patients acquired the disease in Greater São Paulo, seven of whom after 1983. The acute phase Chagas' disease was oligosymptomatic in 4 patients: three of such patients being immunocompromised by drugs or other diseases. Another two adult immunocompromised patients developed myocarditis and congestive heart failure. Clinical features were severe in 5 from 6 children under two years, irrespective of the transmission route. Evaluation of the acute phase patients treated with benznidazol (4-10 mg/kg/day) showed: therapeutic failure in 4/16 (25.0%); possible cure in 9/16 (53.2%) and inconclusive results in 3/16 (18.8%). The antibody and complement-mediated lysis reaction was in keeping with the xenodiagnosis in 18/22 cases, having shown negative results after treatment earlier than classical serological reactions. One aplastic anaemia patient receiving corticosteroid presented lymphoproliferative disease 6 years after being treated with benznidazol for acute Chagas' disease.

Adenoviruses have been reported to infect a variety of birds. Here, we isolated a novel adenovirus from the liver of a dead owl chick (Bengal eagle owl; Bubo bengalensis) at a raptor-breeding facility in Japan and determined the complete genome sequence of the virus. We performed necropsies on the dead owl chicks and found that they had enlarged livers, pericardial edema, and focal necrosis of the liver tissue. Transmission electron microscopy of the liver tissue revealed a virus-like structure, appearing as paracrystalline arrays in the nucleus, and immunohistochemical staining with anti-adenovirus antibodies showed positive reactions in hepatocytes and other cells. Attempts to isolate the virus from homogenized liver tissue of a dead owl chick showed a cytopathic effect on chicken-derived cultured cells after multiple blind passages. Further, we determined the complete genome sequence of this virus and performed phylogenetic analysis, revealing that this adenovirus belongs to the genus Aviadenovirus, forming a cluster with fowl and turkey aviadenoviruses. The amino acid sequence divergence between the DNA polymerase of this virus and its closest known adenovirus relative is approximately 29%, implying that this virus can be assigned to a new species in the genus Aviadenovirus. Based on our data, this novel owl adenovirus is a likely cause of fatal infections in owls, which may threaten wild and captive owl populations. Further, this virus is unique among raptor adenoviruses in that it infects chicken-derived cultured cells, raising the importance of further investigations to evaluate interspecies transmission of this virus., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Purpose: Diffusional kurtosis metrics show high performance for detecting pathological changes and are therefore expected to be disease biomarkers. Kurtosis maps, however, tend to be noisy. The maps' visual quality is crucial for disease diagnosis, even when kurtosis is being used quantitatively. A Bayesian method was proposed to curtail the large statistical error inherent in kurtosis estimation while maintaining potential application to biomarkers., Theory: Gaussian priors are determined from first-step estimations implemented using the least-square method (LSM). The likelihood-function variance is determined from the residuals of the estimation. Although the proposed approach is similar to a regularized LSM, regularization parameters do not have to be artificially adjusted. An appropriate balance between denoising and preventing false shrinkages of metric dispersions is automatically achieved., Methods: Map qualities achieved using the conventional and proposed methods were compared. The receiver-operating characteristic analysis was performed for glioma-grade differentiation using simulated low- and high-grade glioma DWI datasets. Noninferiority of the proposed method was tested for areas under the curves (AUCs)., Results: The noisier the conventional maps, the better the proposed Bayesian method improved them. Noninferiority of the proposed method was confirmed by AUC tests for all kurtosis-related metrics. Superiority of the proposed method was also established for several metrics., Conclusions: The proposed approach improved noisy kurtosis maps while maintaining their performances as biomarkers without increasing data acquisition requirements or arbitrarily choosing LSM regularization parameters. This approach may enable the use of higher-order terms in diffusional kurtosis imaging (DKI) fitting functions by suppressing overfitting, thereby improving the DKI-estimation accuracy., (© 2021 International Society for Magnetic Resonance in Medicine.)

Objective: Surface-rendered three-dimensional (3D) 1.5-T magnetic resonance (MR) imaging is useful for presurgical simulation of microvascular decompression. This study compared the sensitivity and specificity of 1.5- and 3.0-T surface-rendered 3D MR imaging for preoperative identification of the compression vessels of trigeminal neuralgia., Methods: One hundred consecutive patients underwent microvascular decompression for trigeminal neuralgia. Forty and 60 patients were evaluated by 1.5- and 3.0-T MR imaging, respectively. Three-dimensional MR images were constructed on the basis of MR imaging, angiography, and venography data and evaluated to determine the compression vessel before surgery. MR imaging findings were compared with the microsurgical findings to compare the sensitivity and specificity of 1.5- and 3.0-T MR imaging., Results: The agreement between MR imaging and surgical findings depended on the compression vessels. For superior cerebellar artery, 1.5- and 3.0-T MR imaging had 84.4% and 82.7% sensitivity and 100% and 100% specificity, respectively. For anterior inferior cerebellar artery, 1.5- and 3.0-T MR imaging had 33.3% and 50% sensitivity and 92.9% and 95% specificity, respectively. For the petrosal vein, 1.5- and 3.0-T MR imaging had 75% and 64.3% sensitivity and 79.2% and 78.1% specificity, respectively. Complete pain relief was obtained in 36 of 40 and 55 of 60 patients undergoing 1.5- and 3.0-T MR imaging, respectively., Conclusions: The present study showed that both 1.5- and 3.0-T MR imaging provided high sensitivity and specificity for preoperative assessment of the compression vessels of trigeminal neuralgia. Preoperative 3D imaging provided very high quality presurgical simulation, resulting in excellent clinical outcomes., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Purpose: q-ball imaging (QBI) reconstructs the orientation distribution function (ODF) that describes the probability for a spin to diffuse in a given direction, and it is capable of identifying intravoxel multiple fiber orientations. The local maxima of ODF are assumed to indicate fiber orientations, but there is a mismatch between the orientation of a fiber crossing and the local maxima. We propose a novel method, multi-shelled QBI (MS-QBI), that gives a new ODF based on the moment of the probability density function of diffusion displacement. We test the accuracy of the fiber orientation indicated by the new ODF and test fiber tracking using the new ODF., Methods: We performed tests using numerical simulation. To test the accuracy of fiber orientation, we assumed that 2 fibers cross and evaluated the deviation of the measured crossing angle from the actual angle. To test the fiber tracking, we used a numerical phantom of the cerebral hemisphere containing the corpus callosum, projection fibers, and superior longitudinal fasciculus. In the tests, we compared the results between MS-QBI and conventional QBI under the condition of approximately equal total numbers of diffusion signal samplings between the 2 methods and chose the interpolation parameter such that the stabilities of the results of the angular deviation for the 2 methods were the same., Results: The absolute value of the mean angular deviation was smaller in MS-QBI than in conventional QBI. Using the moment-based ODF improved the accuracy of fiber pathways in fiber tracking but maintained the stability of the results., Conclusion: MS-QBI can more accurately identify intravoxel multiple fiber orientations than can QBI, without increasing sampling number. The high accuracy of MS-QBI will contribute to the improved tractography.

q-Space diffusion analysis is a method to obtain the probability density function of the translational displacement of diffusing water molecules. Several quantities can be extracted from the function that indicate a characteristic of the water diffusion in tissue, e.g., the mean displacement of the diffusion, probability for zero displacement, and kurtosis of the function. These quantities are expected to give information about the microstructure of tissues in addition to that obtained from the apparent diffusion coefficient (ADC); however, this method requires high q (i.e., high b) values, which are undesirable in practical applications of the method using clinical magnetic resonance (MR) imaging equipment. We propose a method to obtain certain quantities that indicate a characteristic of the diffusion and that uses low q-value measurements. The quantities we can obtain are the moments of translational displacement, R; the n-th order moment is defined as the average of Rn (n: integer). Kurtosis can also be calculated from the second and fourth moments. We tried to map the moments and kurtosis using clinical MR imaging equipment. We also estimated the inherent errors of the moments obtained. Our method requires precision in measuring spin echo signals and setting q values rather than using high q-value measurements. Although our results show that further error reductions are desired, our method is workable using ordinary clinical MR imaging equipment.

Two Trypanosoma cruzi-derived cloning vectors, pTREX-n and pBs:CalB1/CUB01, were used to drive the expression of green fluorescent protein (GFP) and DsRed in Trypanosoma rangeli Tejera, 1920, and Trypanosoma cruzi Chagas, 1909, isolates, respectively. Regardless of the species, group, or strain, parasites harboring the transfected constructs as either episomes or stable chromosomal integrations showed high-level expression of fluorescent proteins. Tagged flagellates of both species were used to experimentally infect Rhodnius prolixus Stal, 1953. In infected bugs, single or mixed infections of T. cruzi and T. rangeli displayed the typical cycle of each species, with no apparent interspecies interactions. In addition, infection of kidney monkey cells (LLC-MK2) with GFP-T. cruzi showed that the parasite retained its fluorescent tag while carrying out its life cycle within cultured cells. The use of GFP-tagged parasites as a tool for biological studies in experimental hosts is discussed, as is the application of this method for copopulation studies of same-host parasites.

The authors report clinical features and therapeutic response of 24 outpatients with acute Chagas' disease, and 3 in the initial chronic phase, referred to the Clinic for Infectious and Parasitic Diseases of the FMUSP "Clínicas" Hospital between 1974 and 1987. The following transmission routes were involved: triatominae in 7 cases, blood transfusion in 9, kidney transplantation and/or blood transfusion in 4, accidental in 1, oral route in 3, probably breast feeding in 1, congenital or breast feeding in 1, and congenital or blood transfusion in 1. Six patients infected by triatominac acquired the disease between 1974 and 1980 and one in 1987. The blood transfusion infected patients acquired the disease in Greater São Paulo, seven of whom after 1983. The acute phase Chagas' disease was oligosymptomatic in 4 patients: three of such patients being immunocompromised by drugs or other diseases. Another two adult immunocompromised patients developed myocarditis and congestive heart failure. Clinical features were severe in 5 from 6 children under two years, irrespective of the transmission route. Evaluation of the acute phase patients treated with benznidazol (4-10 mg/kg/day) showed: therapeutic failure in 4/16 (25.0%); possible cure in 9/16 (53.2%) and inconclusive results in 3/16 (18.8%). The antibody and complement-mediated lysis reaction was in keeping with the xenodiagnosis in 18/22 cases, having shown negative results after treatment earlier than classical serological reactions. One aplastic anaemia patient receiving corticosteroid presented lymphoproliferative disease 6 years after being treated with benznidazol for acute Chagas' disease.