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BACKGROUND Metformin (MET) is a hypoglycemic drug used for the treatment of diabetes, despite interference in host immunity against microorganisms. Cutaneous infection caused by pathogens such as Leishmania braziliensis (Lb), the agent responsible for cutaneous leishmaniasis (CL) in Brazil, represents an interesting model in which to evaluate the effects associated with MET. OBJECTIVE To evaluate the modulatory effect of MET in Lb infection. MATERIAL AND METHODS Experimental study of Lb infection and MET treatment in BALB/c mice and Raw 264.7 macrophages. FINDINGS MET treatment interfered with lesion kinetics, increased parasite load and reduced macrophage proliferation. Low concentrations of MET in Lb culture allow for the maintenance of stationary parasite growth phase. Lb-infected cells treated with MET exhibited increased parasite load. While both MET and Lb infection alone promoted the production of intracellular reactive oxygen species (ROS), reduced levels of ROS were seen in MET-treated Lb-infected macrophages. MAIN CONCLUSION Experimental treatment with MET interfered with the kinetics of cutaneous ulceration, increased Lb parasite load, altered ROS production and modulated cellular proliferation. Our experimental results indicate that MET interfere with the evolution of CL.

Background Erectile dysfunction (ED) occurs in more than 50% of patients with human T-cell lymphotropic virus type 1 (HTLV-1) infection. In the general population, atherosclerosis is the main risk factor related to ED. Aim To compare the contribution of neurologic disorders from HTLV-1 with that of atherosclerosis as risk factors for ED in men with HTLV-1. Methods In this cross-sectional study, men 18 to 70 years old with HTLV-1 were classified into one of two groups according to the presence or absence of ED. They were compared for obesity, waist circumference, dyslipidemia, metabolic syndrome, diabetes mellitus, high blood pressure, and neurologic manifestations. Comparisons between proportions were performed using the χ2 or Fisher exact test. Logistic regression analysis was performed to identify predictors of ED. Subjects with HTLV-1 were classified into three groups based on Osame's Disability Motor Scale and the Expanded Disability Status Scale: (i) HTLV-1 carriers; (ii) probable HTLV-1–associated myelopathy or tropical spastic paraparesis; and (iii) definitive HTLV-1–associated myelopathy or tropical spastic paraparesis. The International Index of Erectile Function was used to determine the degree of ED. Results In univariate logistic regression, age older 60 years (P = .003), diabetes mellitus (P = .042), and neurologic disease (P < .001) were associated with ED. In the multivariate model, the odds of ED was highest in patients with neurologic disease (odds ratio = 22.1, 95% CI = 5.3–92.3), followed by high blood pressure (odds ratio = 6.3, 95% CI = 1.4-30.5) and age older than 60 years (odds ratio = 4.6, 95% CI = 1.3–17.3). Clinical Implications In men infected with HTLV-1, neurologic dysfunction is a stronger predictor of ED than risk factors for atherosclerosis. Strengths and Limitations The small number of patients limited the power of the statistical analysis, but clearly neurologic manifestations had a greater association with ED than risk factors for atherosclerosis, and there was no association between metabolic syndrome and severity of ED. Conclusion Neurologic impairment is the major cause of ED in individuals infected with HTLV-1 and risk factors for atherosclerosis did not have a strong relation with ED in this population.

Introduction Erectile dysfunction (ED) is associated with neurological damage due to human T-lymphotropic virus 1 (HTLV-1) infection, but hormonal and psychogenic factors also cause ED. Aim To evaluate the association of psychogenic and hormonal factors with ED in men infected with HTLV-1. Methods In this cross-sectional study, we compared total testosterone, follicle stimulating hormone, luteinizing hormone, prolactin, anxiety symptoms, depressive symptoms, and neurologic manifestations in HTLV-1-infected men with or without ED. The International Index of Erectile Function was used to determine the degree of ED. Participants were grouped according to Osame’s Motor Disability Scale and the Expanded Disability Status Scale: HTLV-1-associated myelopathy or tropical spastic paraparesis (HAM/TSP), probable HAM/TSP, or HTLV-1 carrier. Chi-square and Fisher’s exact tests were used to compare the groups, and regression analyses were used to show predictors of ED. Main Outcome Measure Sexual hormonal levels, psychogenic factors, and neurologic disabilities were found to be associated with ED. Results ED was associated with age older than 60 years (P < .001), degree of neurologic involvement (P Clinical Implications Neurological manifestations are a stronger predictor of ED than hormonal and psychogenic factors in HTLV-1-infected men. Strengths & Limitations The statistical power of the study was limited due to the low number of participants, but neurologic manifestations were clearly associated with ED. There was no strong association between hormonal and psychogenic factors and ED. Conclusion Hormonal and psychogenic factors did not show a strong association with ED in individuals with HTLV-1, but neurological manifestations were strongly associated with ED in these individuals.

Leishmaniasis is considered one of the main endemic diseases in the world, and Brazil is among the countries with the highest incidence of cutaneous and mucocutaneous forms of leishmaniasis caused mainly by Leishmania braziliensis. The first-line drugs used in the treatment of leishmaniasis have several limitations: parenteral administration, long duration of treatment, and serious toxicity. One key metabolic characteristic of these parasites is the lack of a de novo purine biosynthesis pathway, making them auxotrophic to purines. Accordingly, they rely solely on the purine salvage pathway for nucleotide synthesis. A better understanding of the purine salvage pathway can reveal details of the biology of L. braziliensis that could, in turn, be used to develop new strategies to combat this parasite. The inosine–uridine nucleoside hydrolase from L. braziliensis (LbIU-NH) plays an important role in the salvage process and is an attractive drug target as there is no similar catalytic activity in mammals. Here is described cloning, heterologous protein expression, and a three-step purification protocol that yielded homogenous recombinant protein. The determination of LbIU-NH steady-state kinetic constants for inosine, adenosine, cytidine, uridine and p-nitrophenyl β-D-ribofuranoside is also reported. These data suggest that LbIU-NH displays characteristics of a nonspecific hydrolase. The thermodynamic profile suggests that D-ribose can bind to free enzyme with favorable enthalpic (ΔH) and entropic (ΔS) contributions. Thermodynamic activation parameters (Ea, ΔG#, ΔS#, ΔH#) for the LbIU-NH-catalyzed chemical reaction, pre-steady-state kinetics, solvent kinetic isotope effects, and pH-rate profiles are also presented. In addition, the crystal structure of LbIU-NH in complex with β-D-ribose and Ca2+ at 1.5 A resolution is described.

Adenylosuccinate lyase (ASL) is involved in both de novo and salvage pathways of purine biosynthesis. ASL belongs to the argininosuccinate lyase/fumarase C superfamily of enzymes which share a general acid–base catalytic mechanism with β-elimination of fumarate as the common product. Cloning, expression, and a method to obtain homogeneous recombinant ASL from Leishmania braziliensis (LbASL) are described. Mass spectrometry analysis of recombinant LbASL, oligomeric state determination and multiple sequence alignment are presented. Steady-state kinetics of LbASL showed a Michaelis–Menten pattern. Isothermal titration calorimetry binding assays suggested that LbASL follows a Uni-Bi ordered kinetic mechanism, in which release of fumarate is followed by AMP to yield free enzyme. Initial velocity data for the reverse reaction and the Haldane relationship allowed calculation of an unfavorable equilibrium constant for the LbASL-catalyzed chemical reaction. The activation energy and thermodynamic activation parameters were estimated. Solvent kinetic isotope effects V/K and V suggest a modest contribution of solvent proton transference during the rate-limiting step of the reaction. Proton inventory data show that the modest normal effect on V arises from a single protonic site, and the transition state fractionation factor value of 0.74 suggests participation of solvent proton transfer in transition-state vibrations perpendicular to the reaction coordinate. pH-rate profiles for kcat and kcat/KM suggested amino acid residues involved in, respectively, catalysis and substrate binding. A model of LbASL was built to provide a structural basis for the experimental data. A better understanding of the mode of action of LbASL is useful for the rational design of antileishmaniasis agents.

Summary Purpose To characterize the voice before and after speech-language intervention, with Humming nasal sound in patients with sequelae Mucosal Leishmaniasis (ML) and Cutaneous Leishmaniasis (CL). Methods Collection of phonation /a:/ from 44 patients with ML and CL for perceptual voice analysis and computed acoustic. The Wilcoxon nonparametric test and Fisher's exact test were used, with significance level of 5%. Results It was observed, prespeech therapy, that 27.7% of participants with ML presented asthenic vocal quality, and for the acoustics characteristics there was a statistically significant result for measures of frequency, frequency disturbance, noise, and subharmonic measurements, indicating phonatory instability, weakness, and noise emission giving the emission a feeling of vocal weakness. After therapy, the subharmonic segment measurements for the group with ML, showing reduction noise emission. Patients with CL had more grade 1 instability (36.4%), indicating tremor in vocal tract structures. After speech therapy, this group presented a reduction in the degree of roughness and reduction of the frequency disturbance measures, indicating a decrease in tension in the larynx and pharynx. Conclusion Even after completing treatment for LM, patients may experience vocal changes due to the sequelae of the disease, like vocal alterations due to nasal lesions or in other locations that interfere in the correct vocal emission. As for participants with CL, no vocal changes would be expected, since these patients present thorax, leg and arm lesions that would not cause problems for the voice. Nevertheless, the two groups of participants presented vocal changes to different degrees before vocal therapy. However, it was observed that patients with ML present vocal alterations with more severe degrees. After the speech-language intervention, the participants of both groups showed vocal improvement, but the group with CL presented more vocal benefits, possibly due to the previous vocal alterations not being so severe.

INTRODUCTION: The forkhead box P3 (FOXP3) plays a role in cell development and control. In the presence of abnormal FOXP3 expression, tumor cells may evade the immunosurveillance of lymphoid cells, the first step for the maintenance of cancer cells in the thyroid tissue. OBJECTIVE: To identify the presence of FOXP3 in papillary thyroid carcinoma (PTC) with and without Hashimoto's Thyroiditis (HT). METHODS: We conducted a series study of cases collected from 2000 to 2008, when 1,438 thyroidectomies were performed. We selected those diagnosed with PTC, comprising 466 cases. 30 patients were randomly selected for purposes of immunohistochemistry with antibodies against FOXP3. RESULT: FOXP3 revealed high positivity for PTC and positive immunostaining was present in 21 (72.4%) from all analyzed cases. There was no difference regarding coexistent HT or not. DISCUSSION AND CONCLUSION: In the present study, it was evidenced that the focal or diffuse FOXP3 expression was commonly observed in neoplastic cells from PTC, hence indicating that the assessment of this molecule expression in suspected cases of thyroid cancer may contribute to its diagnosis. INTRODUÇÃO: O forkhead box P3 (FOXP3) tem o seu papel no desenvolvimento e no controle celular. Na presença de alterações da sua expressão, células tumorais podem escapar da imunovigilância das células linfoides, sendo o primeiro passo para perpetuação das células cancerígenas no tecido tireoidiano. OBJETIVO: Identificar a presença do FOXP3 no carcinoma papilífero da tireoide (CPT), com e sem tireoidite de Hashimoto (TH). MÉTODOS: Foi realizado um estudo de série de casos coletados no período de 2000 a 2008, quando foram realizadas 1.438 tireoidectomias. Destes, foram selecionados aqueles que apresentaram diagnóstico de CPT, perfazendo um total de 466 casos. Desse total, 30 casos de CPT foram selecionados aleatoriamente para fins de exame imuno-histoquímico com o anticorpo contra o FOXP3. RESULTADO: O FOXP3 apresentou alta positividade no CPT; a marcação positiva na imuno-histoquímica esteve presente em 21 (72,4%) de todos os casos analisados. Não houve diferença com relação à coexistência ou não de TH. DISCUSSÃO E CONCLUSÃO: No presente estudo, foi documentado que a expressão difusa ou focal de FOXP3 foi intensamente observada nas células neoplásicas do CPT, indicando que a avaliação da expressão dessa molécula em casos suspeitos de neoplasia da tireoide pode contribuir para o seu diagnóstico.

OBJECTIVE: To compare neurological symptoms and signs in HTLV-1 asymptomatic carriers and HTLV-1 patients with overactive bladder (OB) syndrome. METHODS: We studied 102 HTLV-1 positive individuals without HAM/TSP (HTLV-1 associated myelopathy/tropical spastic paraparesis) divided into two groups according to the presence or absence of OB syndrome. Clinical interview, neurological exam and proviral load was performed in all patients. RESULTS AND CONCLUSIONS: Individuals with OB were more commonly female (84.3 vs. 60.8% of asymptomatics, p=0.01). The prevalence of neurological complaints was higher in OB group, especially hand or foot numbness and arm or leg weakness. There was no difference between the groups in neurological strength and reflexes. Weakness complaint remained strongly associated with OB in multivariate logistic regression analysis adjusting for sex and age [adjusted odds ratio and 95%CI 3.59 (1.45-8.88) in arms and 6.68 (2.63-16.93) in legs]. Proviral load was also different between the two groups with higher level on OB individuals. OBJETIVO: Comparar sintomas e sinais neurológicos em pacientes portadores do HTLV-1 assintomáticos e com síndrome de bexiga hiperativa (BH). MÉTODOS: Foram estudados 102 indivíduos com HTLV-1 sem HAM/TSP (mielopatia associada ao HTLV-I/paraparesia espástica tropical), divididos em dois grupos segundo a presença ou ausência de BH. Foram realizados em todos os pacientes entrevista clínica, exame neurológico e carga proviral. RESULTADOS E CONCLUSÕES: Indivíduos com BH foram na maioria do sexo feminino (84,3 vs. 60,8% dos assintomáticos, p=0,01). A prevalência de queixas neurológicas foi maior no grupo BH, especialmente dormências e fraqueza em extremidades. Não houve diferença entre os grupos em relação a achados do exame neurológico. Fraqueza subjetiva permaneceu fortemente associada com BH na regressão logística multivariada ajustada para sexo e idade [OR e IC95% 3,59 (1,45-8,88) nos braços e 6,68 (2,63-16,93) nas pernas]. A carga proviral foi também diferente entre os dois grupos com nível maior em indivíduos com BH.