692 research outputs found

    Morphometry And Histology Of Gonads From 13 Children With Dysgenetic Male Pseudohermaphroditism

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    Background. - Dysgenetic male pseudohermaphroditism (DMP) is a sexual differentiation disorder characterized by bilateral dysgenetic testes, persistent müllerian structures, and cryptorchidism in individuals with a 46,XY karyotype. However, the histologic criteria for the diagnosis of DMP are poorly established. Objective. - To determine gonadal histology in children with DMP. Patients and Methods. - Between 1996 and 1998, 13 patients with DMP were evaluated on our service. The clinical diagnosis of DMP was based on a 46,XY karyotype, sex ambiguity, high levels of follicle-stimulating hormone and low levels Of antimüllerian hormone, a decreased testosterone response to human chorionic gonadotropin stimulation without accumulation of testosterone precursors, and the presence of müllerian structures. Molecular sequencing the HMGbox region of the SRY gene did not reveal any mutations. Biopsies were performed for 22 of 26 gonads (patient age at the time of biopsy, 16 months to 10 years). Conventional microscopy was used to evaluate mean tubular diameter, tubular fertility index, and number of Sertoli cells per tubular profile. Results. - All 26 gonads were located outside of the labioscrotal folds. Their histologic features varied from only a reduction in tubular size to features of a streak gonad. Five of the 22 gonads grossly resembled a streak gonad. The mean tubular diameter was severely reduced (>30% reduction relative to the normal tubular diameter for the patient's age) in 4 gonads, markedly reduced (10%-30%) in 11 gonads, slightly reduced (<10%) in one gonad, and normal in one gonad. The tubular fertililty index, expressed as the percentage of tubular profiles containing germ cells, was severely reduced (<30% of normal values) in 9 gonads, markedly reduced (50%-30%) in 2 gonads, and normal in 6 gonads. The number of Sertoli cells per tubular profile was elevated in 16 gonads and normal in one gonad. Thin tubules surrounded by fibrous tissue were occasionally observed. Conclusion. - The histologic findings confirmed the clinical diagnosis of DMP in every patient in the present series. However, gonadal histology was variable, and careful morphometric evaluation may be necessary to establish the diagnosis.1255652656Robboy, S.J., Miller, T., Donahoe, P.K., Dysgenesis of testicular and streak gonads in the syndrome of mixed gonadal dysgenesis: Perspective derived from clinicopathologic analysis of twenty-one cases (1982) Hum Pathol, 13, pp. 700-716Troche, V., Hernandez, E., Neoplasia arising in dysgenetic gonads (1986) Obstet Gynecol Surv, 41, pp. 74-79Krasna, I.H., Lee, M.L., Smilow, P., Sciorra, L., Eierman, L., Risk of malignancy in bilateral streak gonads: The role of the Y chromosome (1992) J Pediatr Surg, 27, pp. 1376-1380Rohatgi, M., Gupta, D.K., Menon, P.S., Verma, I.C., Mathur, M., Mixed gonadal dysgenesis and dysgenetic male pseudohermaphroditism - A critical analysis (1992) Indian J Pediatr, 59, pp. 487-500Rey, R.A., Belville, C., Nhou-Fékété, C., Evaluation of gonadal function in 107 intersex patients by means of serum antimüllerian hormone measurement (1999) J Clin Endocrinol Metab, 84, pp. 627-631Stuchi-Perez, E.G., Lukas-Croisier, C., Castro, M., Evaluation of the tubular and interstitial functions of the testis in 46,XY patients with ambiguous genitalia (2000) J Pediatr Endocrinol Metab, 13, pp. 605-612Chang, H.J., Clark, R.D., Bachman, H., The phenotype of 45,X/46,XY mosaicism: An analysis of 92 prenatally diagnosed cases (1990) Am J Hum Genet, 46, pp. 156-167Rajfer, J., Walsh, P.C., Mixed gonadal dysgenesis: Dysgenetic male pseudoher-maphroditism (1981) The Intersex Child: Pediatric and Adolescent Endocrinology, pp. 103-115. , Josso N, ed. Basel, Switzerland: S. KargerBorer, J.G., Nitti, V.W., Glassberg, K.I., Mixed gonadal dysgenesis and dysgenetic male pseudohermaphroditism (1995) J Urol, 153, pp. 1267-1273Donahoe, P.K., Crawford, J.D., Hendren, W.H., Mixed gonadal dysgenesis: Pathogenesis and management (1979) J Pediatr Surg, 14, pp. 287-300Pelletier, J., Bruening, W., Kashtan, C.E., Germline mutations in the Wilms' tumor supressor gene are associated with abnormal urogenital development in Denys-Drash syndrome (1991) Cell, 67, pp. 437-1147Carré-Éusebe, D., Imbeaud, S., Harbison, M., New, M.I., Josso, N., Picard, J.Y., Variants of the anti-Müllerian hormone gene in a compound heterozygote with the persistent Müllerian duct syndrome and his family (1992) Hum Genet, 90, pp. 389-394Nistal, M., Paniagua, R., Non-neoplastic diseases of the testis (1996) Urologic Surgical Pathology, pp. 458-565. , Bostiwick DG, Eble JN, eds. St Louis, Mo: MosbyLennox, B., Ahmad, K.M., Mack, W.S., A method for determining the relative total length of the tubules in the testis (1970) J Pathol, 102, pp. 229-238Jimenez, R., Sanchez, A., Burgos, M., Dias De La Guardia, R.C., Puzzling out the genetics of mammalian sex determination (1996) Trends Genet, 12, pp. 164-166Müller, J., Skakkebaek, N.F., Quantification of germ cells and seminiferous tubules by stereological examination of testicles from 50 boys who suffered from sudden death (1983) Int J Androl, 6, pp. 143-156Cortes, D., Müller, J., Skakkebaek, N.E., Proliferation of Sertoli cells during development of the human testis assessed by stereological methods (1987) Int J Androl, 10, pp. 589-596Nistal, M., Abaurrea, M.A., Paniagua, R., Morphological and histometric study on the human Sertoli cell from birth to the onset of puberty (1982) J Anat, 14, pp. 351-363Van Niekerk, W.A., Retief, A.E., The gonads of human true hermaphrodites (1981) Hum Genet, 58, pp. 117-122Guerra Jr., G., De Mello, M.P., Assumpção, J.G., True hermaphrodites in the southeastern region of Brazil: A different cytogenetic and gonadal profile (1998) J Pediatr Endocrinol Metab, 11, pp. 519-524Quigley, C.A., De Bellis, A., Marschke, K.B., El-Awady, M.K., Wilson, E.M., French, F.S., Androgen receptor defects: Historical, clinical and molecular perspectives (1995) Endocr Rev, 16, pp. 271-32

    Identificação molecular de Bartonella henselae em paciente com SIDA soronegativo para doença da arranhadura do gato no Rio de Janeiro, Brasil

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    Bartonella henselae is associated with a wide spectrum of clinical manifestations, including cat scratch disease, endocarditis and meningoencephalitis, in immunocompetent and immunocompromised patients. We report the first molecularly confirmed case of B. henselae infection in an AIDS patient in state of Rio de Janeiro, Brazil. Although DNA sequence of B. henselae has been detected by polymerase chain reaction in a lymph node biopsy, acute and convalescent sera were nonreactive.Bartonella henselae está associada a um amplo espectro de manifestações clínicas, incluindo a doença da arranhadura de gato, endocardite, e meningoencefalite, em pacientes imunocompetentes e imunocomprometidos. Relatamos o primeiro caso confirmado por método molecular de B. henselae em um paciente com SIDA no estado do Rio de Janeiro, Brasil. Apesar da sequência de DNA de B. henselae ser detectada pela reação em cadeia da polimerase em uma biópsia do linfonodo, soros das fases aguda e convalescente foram não reativos

    Inferring stabilizing mutations from protein phylogenies : application to influenza hemagglutinin

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    One selection pressure shaping sequence evolution is the requirement that a protein fold with sufficient stability to perform its biological functions. We present a conceptual framework that explains how this requirement causes the probability that a particular amino acid mutation is fixed during evolution to depend on its effect on protein stability. We mathematically formalize this framework to develop a Bayesian approach for inferring the stability effects of individual mutations from homologous protein sequences of known phylogeny. This approach is able to predict published experimentally measured mutational stability effects (ΔΔG values) with an accuracy that exceeds both a state-of-the-art physicochemical modeling program and the sequence-based consensus approach. As a further test, we use our phylogenetic inference approach to predict stabilizing mutations to influenza hemagglutinin. We introduce these mutations into a temperature-sensitive influenza virus with a defect in its hemagglutinin gene and experimentally demonstrate that some of the mutations allow the virus to grow at higher temperatures. Our work therefore describes a powerful new approach for predicting stabilizing mutations that can be successfully applied even to large, complex proteins such as hemagglutinin. This approach also makes a mathematical link between phylogenetics and experimentally measurable protein properties, potentially paving the way for more accurate analyses of molecular evolution

    Evaluating indices of traditional ecological knowledge: a methodological contribution

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    BACKGROUND: New quantitative methods to collect and analyze data have produced novel findings in ethnobiology. A common application of quantitative methods in ethnobiology is to assess the traditional ecological knowledge of individuals. Few studies have addressed reliability of indices of traditional ecological knowledge constructed with different quantitative methods. METHODS: We assessed the associations among eight indices of traditional ecological knowledge from data collected from 650 native Amazonians. We computed Spearman correlations, Chronbach's alpha, and principal components factor analysis for the eight indices. RESULTS: We found that indices derived from different raw data were weakly correlated (rho<0.5), whereas indices derived from the same raw data were highly correlated (rho>0.5; p < 0.001). We also found a relatively high internal consistency across data from the eight indices (Chronbach's alpha = 0.78). Last, results from a principal components factor analysis of the eight indices suggest that the eight indices were positively related, although the association was low when considering only the first factor. CONCLUSION: A possible explanation for the relatively low correlation between indices derived from different raw data, but relatively high internal consistency of the eight indices is that the methods capture different aspects of an individual's traditional ecological knowledge. To develop a reliable measure of traditional ecological knowledge, researchers should collect raw data using a variety of methods and then generate an aggregated measure that contains data from the various components of traditional ecological knowledge. Failure to do this will hinder cross-cultural comparisons

    Use of antibiotic spacers for knee endoprosthesis infections treatment

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    OBJCTIVE: The aim of this study is to evaluate the use of cement spacers impregnated with antibiotics for the treatment of infections in the nonconventional endoprostheses of the knee. METHODOLOGY: We have treated seven patients since 2004 (of which six were submitted to surgery in our service and one patient had been submitted to a primary tumor surgery in another removal service) with deep infection in knee tumor prosthesis. All patients were submitted to endoprosthesis removal and reconstructed with antibiotic cement spacer. All patients were monitored both clinically and by lab tests as for monitoring the evolution, being considered able for reviews after 6 (six) months without infections signs. RESULTS: We have noted a small predominance of infectious processes on the prosthesis inserted on proximal tibia as compared with distal femur (57.1% x 42.9%). The mean follow-up time of patients was 68.2 months. During the follow up, one patient died as a result of the root disease. Six patients out of seven were regarded as cured and one persisted with infection signs and symptoms. CONCLUSION: The results obtained up to date have motivated us to continue using this method of treatment.OBJETIVO: O objetivo do estudo é avaliar a utilização dos espaçadores de cimento acrílico com antibiótico no tratamento das infecções em endopróteses não convencionais de joelho. MÉTODO: Desde de 2004 foram tratados sete pacientes (seis pacientes operados no nosso serviço e um paciente que havia sido submetido a cirurgia primária do tumor em outro serviço) com infecção peri-endoprótese não convencional de joelho. Todos pacientes foram submetidos a retirada da endoprótese e reconstrução com espaçador com cimento acrílico com antibiótico. Todos os pacientes foram monitorados clínica e laboratorialmente quanto ao controle da evolução, sendo considerados aptos para a revisão e recolocação de endoprótese após 06 (seis) meses sem sinais infecciosos RESULTADOS: Notamos um discreto predomínio do do processo infeccioso nas próteses realizadas na tíbia proximal em comparação com o fêmur distal (57,1% x 42,9%). O seguimento médio dos pacientes foi 68,2 meses. Durante o seguimento, um paciente faleceu devido a doença de base. Dos sete pacientes, 6 foram considerados curados e um persistiu com sinais e sintomas de infecção. CONCLUSÃO: Os resultados obtidos até o momento tem motivado a continuidade deste método de tratamento.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de Ortopedia e TraumatologiaUNIFESP, EPM, Depto. de Ortopedia e TraumatologiaSciEL

    Genome-Scale Analysis of Translation Elongation with a Ribosome Flow Model

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    We describe the first large scale analysis of gene translation that is based on a model that takes into account the physical and dynamical nature of this process. The Ribosomal Flow Model (RFM) predicts fundamental features of the translation process, including translation rates, protein abundance levels, ribosomal densities and the relation between all these variables, better than alternative (‘non-physical’) approaches. In addition, we show that the RFM can be used for accurate inference of various other quantities including genes' initiation rates and translation costs. These quantities could not be inferred by previous predictors. We find that increasing the number of available ribosomes (or equivalently the initiation rate) increases the genomic translation rate and the mean ribosome density only up to a certain point, beyond which both saturate. Strikingly, assuming that the translation system is tuned to work at the pre-saturation point maximizes the predictive power of the model with respect to experimental data. This result suggests that in all organisms that were analyzed (from bacteria to Human), the global initiation rate is optimized to attain the pre-saturation point. The fact that similar results were not observed for heterologous genes indicates that this feature is under selection. Remarkably, the gap between the performance of the RFM and alternative predictors is strikingly large in the case of heterologous genes, testifying to the model's promising biotechnological value in predicting the abundance of heterologous proteins before expressing them in the desired host
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