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Background: Obtaining an adequate image of the needle by ultrasound reduces complications resulting from punctures, increasing patient safety and reducing hospitalization costs. Objectives: To verify human perception in relation to number of pixels, while also identifying the best puncture angle and which needle should be used, and to evaluate whether there is a difference if needle visualization software is used. Methods: 20 images were analyzed by 103 students who classified them as being sufficient or insufficient and were compared with the quality observed using photoshop. We evaluated whether there were differences between puncture angles of less than 45º and more than 45º, between IV catheter and introducer needles, and between images obtained with and without visualization software. Results: There was a higher percentage of sufficient ratings for images those that had more than 60 pixels and when the puncture angle was less than 45º, with significant associations between students' evaluations and each of these groups (p < 0.001). The percentages of images classified as sufficient were higher for images in which a IV catheter was used and also higher for those using the needle visualization software, with significant associations between the results for students' classifications and each of these groups (p < 0.001). Conclusions: The human eye classifies an image as sufficient according to higher numbers of pixels. Images of punctures at angles smaller than 45º in relation to the surface, of punctures performed with a IV catheter, and when using specific visualization software are also better detected by the human eye.
Contexto: A obtenção de uma imagem adequada da agulha pelo ultrassom diminui complicações decorrentes de punções, trazendo segurança para os pacientes e diminuindo custos com hospitalização. Objetivos: Verificar a percepção do olho humano em relação aos pixels, identificar qual o melhor ângulo da punção e qual agulha deve ser utilizada e avaliar se há diferença com o uso de software de visualização de agulha. Métodos: Vinte imagens foram analisadas por 103 alunos, que as classificaram como sendo suficientes ou insuficientes, e comparadas com a qualidade observada pelo photoshop. Avaliou-se se havia diferença entre punções com menos de 45º e mais de 45º, entre cateter EV e agulha introdutora e entre imagens obtidas com e sem software de visualização. Resultados: Houve um percentual mais elevado de imagens suficientes entre aquelas que tinham mais de 60 pixels e quando o ângulo era menor que 45º, com associação significativa entre a classificação das avaliações pelos alunos e cada um desses grupos (p < 0,001). O percentual de imagens suficientes foi maior nas imagens realizadas com cateter EV e naquelas que utilizaram o software de visualização da agulha, ocorrendo associação significativa entre os resultados da classificação pelos alunos e cada um desses grupos (p < 0,001). Conclusões: O olho humano classifica a imagem como sendo suficiente de acordo com a maior quantidade de pixels. Imagens puncionadas com ângulos menores que 45º em relação à superfície, realizadas com cateter EV e utilizando software específico de visualização também são mais bem detectadas pelo olho humano.
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Foodborne diseases are common illnesses caused by the consumption of food contaminated with microorganisms, such as viruses, fungi, bacteria, and protozoa. Every year, 600 million people become ill and 420,000 people die as a result of consuming contaminated food. Therefore, food safety is an important issue. In this study, samples of homemade spiced mayonnaise and self-serve acai sold in the city of Araguaína, Tocantins, Brazil were analyzed for microbiological contaminants. Acai was collected from 10 stores, one sample from each store, and tested for mold, yeast, and coliforms, as well as coliform identification and total and thermotolerant coliform counts. Mayonnaise was collected from 20 snack bars, one sample from each. These samples were inoculated on MacConkey and Salmonella Shigella agar plates, and the plates were analyzed for growth. Salmonella spp. were detected in some Mayonnaise samples, and coliforms were detected in all acai samples; 60% of samples had thermotolerant coliforms, and only 40% were within the limits established by ANVISA. The collected samples of mayonnaise and acai were contaminated with molds and yeasts above the established limit of 103 CFU/g. Thus, the analyzed mayonnaise and acai samples were contaminated and unfit for consumption, demonstrating the importance of hygienic-sanitary measures in food handling.
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Alimentos , Humanos , Brasil , AgarRESUMEN
The present study was performed in an area endemic for Brazilian spotted fever (BSF) in Juiz de Fora, state of Minas Gerais, Brazil, during the years 2007 and 2008, when fatal cases of BSF (caused by Rickettsia rickettsii) were reported. Adult ticks (Acari: Ixodidae) identified as Rhipicephalus sanguineus (Latreille) and Amblyomma cajennense (Fabricius) were collected from dogs and horses, respectively, and tested by polymerase chain reaction (PCR). Overall, 13.1% of the Rh. sanguineus ticks and none of the A. cajennense were found to be infected with R. rickettsii. Two isolates of R. rickettsii were successfully established in Vero cell culture from two Rh. sanguineus ticks. An indirect immunofluorescence assay (IFA) using R. rickettsii antigens detected blood serological reaction to R. rickettsii in 67.9% (53/78) of dogs and 41.0% (16/39) of horses living in the study area. Larval offspring from two Rh. sanguineus engorged females, naturally infected by R. rickettsii, were reared to adult stage in the laboratory. All active stages (larvae, nymphs, adults) remained 100% infected by R. rickettsii, which was efficiently transmitted to naïve rabbits. Overall, the results of the present study indicate a potential risk for transmission of R. rickettsii to humans by Rh. sanguineus, an occurrence yet to be documented in Brazil.
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Anticuerpos Antibacterianos/sangre , Enfermedades de los Perros/microbiología , Enfermedades de los Caballos/microbiología , Ixodidae/microbiología , Rickettsia rickettsii/aislamiento & purificación , Fiebre Maculosa de las Montañas Rocosas/veterinaria , Animales , Anticuerpos Antibacterianos/inmunología , Brasil/epidemiología , Células Cultivadas , Chlorocebus aethiops , Enfermedades de los Perros/sangre , Enfermedades de los Perros/epidemiología , Perros , Femenino , Técnica del Anticuerpo Fluorescente , Enfermedades de los Caballos/sangre , Enfermedades de los Caballos/epidemiología , Caballos , Lagomorpha/sangre , Lagomorpha/microbiología , Masculino , Reacción en Cadena de la Polimerasa , Rhipicephalus sanguineus/microbiología , Rickettsia rickettsii/genética , Fiebre Maculosa de las Montañas Rocosas/sangre , Fiebre Maculosa de las Montañas Rocosas/epidemiología , Fiebre Maculosa de las Montañas Rocosas/microbiología , Células VeroRESUMEN
Constrained by the Nielsen-Ninomiya no-go theorem, in all so-far experimentally determined Weyl semimetals (WSMs) the Weyl points (WPs) always appear in pairs in the momentum space with no exception. As a consequence, Fermi arcs occur on surfaces which connect the projections of the WPs with opposite chiral charges. However, this situation can be circumvented in the case of unpaired WP, without relevant surface Fermi arc connecting its surface projection, appearing singularly, while its Berry curvature field is absorbed by nontrivial charged nodal walls. Here, combining angle-resolved photoemission spectroscopy with density functional theory calculations, we show experimentally that a singular Weyl point emerges in PtGa at the center of the Brillouin zone (BZ), which is surrounded by closed Weyl nodal walls located at the BZ boundaries and there is no Fermi arc connecting its surface projection. Our results reveal that nontrivial band crossings of different dimensionalities can emerge concomitantly in condensed matter, while their coexistence ensures the net topological charge of different dimensional topological objects to be zero. Our observation extends the applicable range of the original Nielsen-Ninomiya no-go theorem which was derived from zero dimensional paired WPs with opposite chirality.
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OBJECTIVE: To investigate if early treatment of primary HIV-1 infection (PHI) reduces viral set point and/or increases CD4 lymphocytes. METHODS: Analysis of two prospective multi-centre PHI cohorts. HIV-1 RNA and CD4 lymphocytes in patients with transient treatment were compared to those in untreated patients. Time to CD4 lymphocyte decrease below 350/ microl after treatment stop or seroconversion was calculated using Kaplan-Meier and Cox-PH-regression analyses. RESULTS: 156 cases of PHI were included, of which 100 had received transient HAART (median treatment time 9.5 months) and 56 remained untreated. Median viral load (563000 cop/ml vs 240000 cop/ml; p<0.001) and median CD4 lymphocyte (449/ microl vs. 613/ microl; p<0.01) differed significantly between treated and untreated patients. Median viral load was 38056 copies/ml in treated patients (12 months after treatment stop) and 52880 copies/ml in untreated patients (12 months after seroconversion; ns). Median CD4 lymphocyte change was +60/ microl vs. -86/ microl (p = 0.01). Median time until CD4 lymphocytes decreased to <350/ microl (including all patients with CD4 lymphocytes <500/ microl during seroconversion) was 20.7 months in treated patients after treatment stop and 8.3 months in untreated patents after seroconversion (p<0.01). Cox-PH analyses adjusting for baseline VL, CD4 lymphocytes, stage of early infection and symptoms confirmed these differences. CONCLUSIONS: Treatment during PHI did not lower viral set point. However, patients treated during seroconversion had an increase in CD4 lymphocytes, whereas untreated patients experienced a decrease in CD4 lymphocytes. Time until reaching CD4 lymphocytes <350/ microl was significantly shorter in untreated than in treated patients including patients with CD4 lymphocytes <500/ microl during seroconversion.
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Terapia Antirretroviral Altamente Activa/métodos , Recuento de Linfocito CD4 , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Adolescente , Adulto , Estudios de Cohortes , Femenino , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Seropositividad para VIH/tratamiento farmacológico , Seropositividad para VIH/inmunología , Seropositividad para VIH/virología , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Evaluación de Resultado en la Atención de Salud/métodos , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Modelos de Riesgos Proporcionales , Factores de Tiempo , Carga Viral , Adulto JovenRESUMEN
The chemical and dimensional stability associated with suitable fracture toughness and propitious tribological characteristics make silicon nitride-based ceramics potential candidates for biomedical applications, mainly as orthopedic implants. Considering this combination of properties, silicon nitride components were investigated in relation to their biocompatibility. For this study, two cylindrical implants were installed in each tibia of five rabbits and were kept in the animals for 8 weeks. During the healing time, tissue tracers were administrated in the animals so as to evaluate the bone growth around the implants. Eight weeks after the surgery, the animals were euthanized and histological analyses were performed. No adverse reactions were observed close to the implant. The osteogenesis process occurred during the entire period defined by the tracers. However, this process occurred more intensely 4 weeks after the surgery. In addition, the histological analyses showed that bone growth occurred preferentially in the cortical areas. Different kinds of tissue were identified on the implant surface, characterized by lamellar bone tissue containing osteocytes and osteons, by a noncalcified matrix containing osteoblasts, or by the presence of collagen III, which may change to collagen I or remain as a fibrous tissue. The results demonstrated that silicon nitride obtained according to the procedure proposed in this research is a biocompatible material.
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Materiales Biocompatibles/farmacología , Ensayo de Materiales , Compuestos de Silicona/farmacología , Animales , Conducción Ósea/efectos de los fármacos , Remodelación Ósea/efectos de los fármacos , Huesos/anatomía & histología , Colorantes , Femenino , Microscopía Fluorescente , Microscopía de Polarización , Prótesis e Implantes , Conejos , Cloruro de TolonioRESUMEN
In this paper the algorithm for ΔρDCCA statistical test (Guedes et al., 2018) [1] is presented. Our test begins with the simulation of four time series pairs, by an ARFIMA process. These time series has N=250 , 500, 1000, and 2000 points, see Guedes et al. (2018) [1]. The probability distribution function (PDF) is made available for all 10,000 samples, that start from the original time series, in supplementary material.
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Abstract Background Obtaining an adequate image of the needle by ultrasound reduces complications resulting from punctures, increasing patient safety and reducing hospitalization costs. Objectives To verify human perception in relation to number of pixels, while also identifying the best puncture angle and which needle should be used, and to evaluate whether there is a difference if needle visualization software is used. Methods 20 images were analyzed by 103 students who classified them as being sufficient or insufficient and were compared with the quality observed using photoshop. We evaluated whether there were differences between puncture angles of less than 45º and more than 45º, between IV catheter and introducer needles, and between images obtained with and without visualization software. Results There was a higher percentage of sufficient ratings for images those that had more than 60 pixels and when the puncture angle was less than 45º, with significant associations between students' evaluations and each of these groups (p < 0.001). The percentages of images classified as sufficient were higher for images in which a IV catheter was used and also higher for those using the needle visualization software, with significant associations between the results for students' classifications and each of these groups (p < 0.001). Conclusions The human eye classifies an image as sufficient according to higher numbers of pixels. Images of punctures at angles smaller than 45º in relation to the surface, of punctures performed with a IV catheter, and when using specific visualization software are also better detected by the human eye.
Resumo Contexto A obtenção de uma imagem adequada da agulha pelo ultrassom diminui complicações decorrentes de punções, trazendo segurança para os pacientes e diminuindo custos com hospitalização. Objetivos Verificar a percepção do olho humano em relação aos pixels, identificar qual o melhor ângulo da punção e qual agulha deve ser utilizada e avaliar se há diferença com o uso de software de visualização de agulha. Métodos Vinte imagens foram analisadas por 103 alunos, que as classificaram como sendo suficientes ou insuficientes, e comparadas com a qualidade observada pelo photoshop. Avaliou-se se havia diferença entre punções com menos de 45º e mais de 45º, entre cateter EV e agulha introdutora e entre imagens obtidas com e sem software de visualização. Resultados Houve um percentual mais elevado de imagens suficientes entre aquelas que tinham mais de 60 pixels e quando o ângulo era menor que 45º, com associação significativa entre a classificação das avaliações pelos alunos e cada um desses grupos (p < 0,001). O percentual de imagens suficientes foi maior nas imagens realizadas com cateter EV e naquelas que utilizaram o software de visualização da agulha, ocorrendo associação significativa entre os resultados da classificação pelos alunos e cada um desses grupos (p < 0,001). Conclusões O olho humano classifica a imagem como sendo suficiente de acordo com a maior quantidade de pixels. Imagens puncionadas com ângulos menores que 45º em relação à superfície, realizadas com cateter EV e utilizando software específico de visualização também são mais bem detectadas pelo olho humano.
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PURPOSE: To determine the efficacy and toxicity of docetaxel in patients with müllerian carcinoma resistant to paclitaxel. PATIENTS AND METHODS: Thirty-two patients with epithelial ovarian cancer, fallopian tube cancer, or primary peritoneal cancer who failed paclitaxel-based chemotherapy received either 100 or 75 mg/m(2) of docetaxel every 3 weeks. Resistance to paclitaxel was defined as either progression of disease during treatment, failure to achieve regression of disease after at least four courses, or rapid recurrence (within 6 months) after completion of therapy. RESULTS: Eighteen patients were treated on a formal protocol and fourteen with the commercially available docetaxel. Thirty were assessable for response. Toxicities were thoroughly evaluated in the 18 patients on protocol. Twenty-seven patients (85%) had epithelial ovarian cancer. The overall response rate was 23% (one complete and six partial responses), with a median survival time of 44 weeks (9.5 months). Nine patients had stable disease and 14 progressive disease. Among 19 patients who progressed during prior paclitaxel treatment, two (11%) responded to docetaxel, compared with five (45%) of 11 patients in other paclitaxel-resistance categories. The responders had a median taxane-free interval (ie, the time between the last paclitaxel and first docetaxel treatment) of 73 weeks, compared with 19 weeks for the nonresponder group. Toxic effects were as expected. CONCLUSION: Docetaxel is an active chemotherapeutic agent in patients with müllerian carcinoma previously treated with paclitaxel-based chemotherapy, especially in the patients who had a long taxane-free interval after a previous short response to paclitaxel.
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Antineoplásicos Fitogénicos/uso terapéutico , Carcinoma/tratamiento farmacológico , Neoplasias de las Trompas Uterinas/tratamiento farmacológico , Neoplasias Ováricas/tratamiento farmacológico , Paclitaxel/análogos & derivados , Neoplasias Peritoneales/tratamiento farmacológico , Taxoides , Adulto , Anciano , Docetaxel , Resistencia a Antineoplásicos , Femenino , Humanos , Persona de Mediana Edad , Paclitaxel/uso terapéutico , Estudios Prospectivos , Estadísticas no Paramétricas , Análisis de SupervivenciaRESUMEN
OBJECTIVE: To evaluate the long-term effects of antiretroviral treatment (ART) interruptions on metabolic, immunological, virological and clinical outcomes in chronically HIV-1 infected patients. METHODS: Multi-centric, prospective, controlled 24-month cohort study in HIV-1 infected patients interrupting ART once or several times and for at least two weeks. Patients were compared to a frequency-matched control group continuing on ART. RESULTS: A total of 399 HIV-1 infected patients were included, among them 133 patients with treatment interruption (TI) and 266 control patients. Baseline characteristics were well matched. Median baseline CD4 cell count was 379/microl in TI-patients and 410/microl in control patients (p = ns). Median duration of the first TI was 1.1 months, and 37 % of patients had two or further TI's. Whereas CD4 cell count in control patients had increased significantly by a median of 67/microl at month 24 (p<0.0001), median CD4 cell count at month 24 in the TI-patients did not differ significantly from baseline. However, two-year AIDS-free survival was not significantly different between TI- and control patients. Liver enzymes and blood lipids improved significantly during TI. CONCLUSION: TI was associated with a significant immunological disadvantage at 24-month follow-up compared to continued ART. In this relatively immunocompetent cohort, however, TI's did not lead to an increased risk of disease progression within two years of follow-up.
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Terapia Antirretroviral Altamente Activa , Infecciones por VIH/tratamiento farmacológico , VIH-1/patogenicidad , Privación de Tratamiento , Adulto , Anciano , Fosfatasa Alcalina/metabolismo , Recuento de Linfocito CD4 , Enfermedad Crónica , Estudios de Cohortes , Progresión de la Enfermedad , Femenino , Infecciones por VIH/inmunología , Humanos , Lípidos/sangre , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Tiempo , Carga ViralRESUMEN
The family physician plays a crucial role in the diagnosis as well as in the medical care of the HIV patient. In making the diagnosis, he is the first contact person and, in the case of symptomatic patients, should immediately establish contact with an HIV treatment center. The therapy and care of the immunocompetent asymptomatic HIV patient can be primarily carried out in the family practice. The complexity of the antiviral therapy requires an experienced HIV specialist. The co-attending family doctor should supervise the patient locally especially when the specialized treatment practice is far away and, when serious side effects occur, maintain close telephone contact to the specialists. Knowledge of the interactions of the antiviral combination therapy with other medications is also important. Prerequisite for a successful HIV therapy is the collaboration between the HIV specialist and the family physician.
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Seropositividad para VIH/diagnóstico , Relaciones Médico-Paciente , Serodiagnóstico del SIDA , Fármacos Anti-VIH/efectos adversos , Fármacos Anti-VIH/uso terapéutico , Terapia Antirretroviral Altamente Activa/efectos adversos , Recuento de Linfocito CD4 , Medicina Familiar y Comunitaria , Seropositividad para VIH/tratamiento farmacológico , Seropositividad para VIH/psicología , Humanos , Pronóstico , Revelación de la Verdad , Carga ViralRESUMEN
A previous study in Paulicéia Municipality, south-eastern Brazil, reported 9.7% of the Amblyomma triste ticks to be infected by Rickettsia parkeri, a bacterial pathogen that causes spotted fever in humans. These A. triste ticks were shown to be associated with marsh areas, where the marsh deer Blastocerus dichotomus is a primary host for this tick species. During 2008-2009, blood serum samples were collected from 140 horses, 41 dogs, 5 opossums (Didelphis albiventris) and 26 humans in farms from Pauliceia Municipality. Ticks were collected from these animals, from vegetation and from additional wildlife in these farms. Overall, 25% (35/140) of the horses, 7.3% (3/41) of the dogs, 3.8% (1/26) of the humans and 100% (5/5) of the opossums were seroreactive (titre ≥64) to spotted fever group (SFG) Rickettsia spp. Multivariate statistical analysis indicated that horses that were allowed to forage in the marsh were 4.8 times more likely to be seroreactive to spotted fever group (SFG) Rickettsia spp than horses that did not forage in the marsh. In addition, horses that had been living in the farm for more than 8.5 years were 2.8 times more likely to be seroreactive to SFG Rickettsia spp than horses that were living for ≤8.5 years. Ticks collected from domestic animals or from vegetation included Amblyomma cajennense, Amblyomma coelebs, Amblyomma dubitatum, Dermacentor nitens and Rhipicephalus microplus. By PCR analyses, only one pool of A. coelebs ticks from the vegetation was shown to be infected by rickettsiae, for which DNA sequencing revealed to be Rickettsia amblyommii. Ticks (not tested by PCR) collected from wildlife encompassed A. cajennense and Amblyomma rotundatum on lizards (Tupinambis sp), and A. cajennense and A. triste on the bird Laterallus viridis. Our results indicate that the marsh area of Paulicéia offers risks of infection by SFG rickettsiae.
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Infecciones por Rickettsia/microbiología , Infecciones por Rickettsia/transmisión , Rickettsia/aislamiento & purificación , Enfermedades por Picaduras de Garrapatas/microbiología , Agricultura , Animales , Antígenos Bacterianos , Vectores Arácnidos/microbiología , Brasil/epidemiología , Perros/microbiología , Femenino , Caballos/microbiología , Humanos , Masculino , Análisis Multivariante , Zarigüeyas/microbiología , Reacción en Cadena de la Polimerasa , Rickettsia/genética , Infecciones por Rickettsia/sangre , Infecciones por Rickettsia/epidemiología , Factores de Riesgo , Enfermedades por Picaduras de Garrapatas/sangre , Enfermedades por Picaduras de Garrapatas/epidemiología , Garrapatas/microbiologíaRESUMEN
To study the pulmonary complications in leptospirosis case records of 23 such patients admitted at the Hospital Universitário Antônio Pedro, Universidade Federal Fluminense, Niterói, Brasil, were reviewed. Hemoptysis were seen in 21.7% and sputal blood in 30.4% of patients. Arterial gasometry detected hypoxemia and hypocapnia in most cases. Thoracic radiology showed an alveolar pattern in 60% of the patients, alveolo-interstitial in 20%, interstitial in 6%, and in 14% the lungs were considered to be normal. Necropsy of 13 cases showed edema, congestion and hemorrhage in the lungs in all cases. Hyaline membrane was found in 30% and fibrin thrombi in 46% of these cases, resulting in a diagnosis of adult respiratory distress syndrome and acute disseminated intravascular coagulation (consumption coagulopathy) in leptospirosis.
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Leptospira interrogans serovar canicola , Leptospirosis/diagnóstico , Enfermedades Pulmonares/diagnóstico , Enfermedad de Weil/diagnóstico , Adulto , Anciano , Anticuerpos Antibacterianos/sangre , Femenino , Humanos , Leptospira interrogans/inmunología , Leptospira interrogans serovar canicola/inmunología , Leptospirosis/complicaciones , Leptospirosis/patología , Pulmón/diagnóstico por imagen , Pulmón/patología , Enfermedades Pulmonares/etiología , Enfermedades Pulmonares/patología , Masculino , Persona de Mediana Edad , Radiografía , Enfermedad de Weil/complicaciones , Enfermedad de Weil/patologíaRESUMEN
Human leptospirosis, one of the main urban endemics/epidemics in Brazil, has dramatically grown in the last three decades, especially after floods caused by summer rains. This presentation describes recent changes in the clinical patterns of this pathology in our region, expressed by the emergence of massive haemoptysis and acute respiratory distress syndrome, or both conditions associated. The evident changes in the respiratory structures emerged as a serious life threat and death mechanisms, becoming the main cause of death in leptospirosis among us because of their high incidence. This new face of the disease demands a revision of current concepts about its seriousness and raises speculations about the pathogenesis of such alterations.
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Hemoptisis/patología , Leptospirosis/patología , Síndrome de Dificultad Respiratoria/patología , Enfermedad de Weil/patología , Adulto , Brasil/epidemiología , Causas de Muerte , Resultado Fatal , Femenino , Hemoptisis/etiología , Hemoptisis/mortalidad , Humanos , Leptospirosis/complicaciones , Leptospirosis/mortalidad , Masculino , Persona de Mediana Edad , Síndrome de Dificultad Respiratoria/etiología , Síndrome de Dificultad Respiratoria/mortalidad , Enfermedad de Weil/complicaciones , Enfermedad de Weil/mortalidadRESUMEN
The effects of undernutrition on the "gastrocnemius plantaris" muscle of young albino rats were observed with light and electronmicroscopy and were compared with controls. Pregnant rats received a diet containing 6.7% protein and the neonates had a 3.2% protein diet after weaning. A total number of 40 animals were distributed in two groups: one hypoproteic and one control. Half of the animals of each group were killed 15 days after birth and the remaining ones at 30 days. We could observe important reduction in the weight of the undernourished rats reaching about 50% when compared with the control animals. An important reduction in the diameter of muscle fibers was noted in undernourished rats. Histochemical reactions showed that not only the type I but also the type II fibers were involved, the latter being more severely reduced in size. Type II fibers os small diameter, resembling F (fetal) fiber were found in animals at 15 days indicating a delay in maturation. Ultrastructural evaluation of the muscle did not show specific changes except for a severe reduction in the caliber of fibers when compared with control animals. We concluded that there was hypoplasia and not atrophy of the muscular tissue in animals submitted to pre- and post-natal undernutrition. The present study, associated with others in which the spinal motor cells and peripheral nerves of undernourished rats were analysed, allow us to consider that with protein deprivation there is a delay in the development, a hypoplasia of the motor unit. We think that in infantile progressive spinal amyotrophy (Werdnig-Hoffmann disease) there is possibly hypoplasia and not atrophy of the type II fibers and we postulate that a metabolic proteic problem is involved in this disease.