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1.
Microsc Res Tech ; 87(2): 403-407, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37877624

RESUMO

The histology of blood vessels shows they are structured in three layers or tunics: tunica intima, which includes the internal limiting lamina with high elastin content; tunica media of smooth muscles fibers of circular disposition, which includes the external limiting lamina; and tunica adventitia of connective tissue. The vascular system is essential in regulating body temperature, especially in the scrotum and testis. This study aimed to analyze the histology of the scrotal arteries and their possible relationship to testicular temperature homeostasis. This study used scrotal samples from human adults, anonymized and obtained from the University of Chile's teaching bank. The control group corresponds to an arteriole of muscle tissue. The results show that the middle layer of the scrotal artery is made up of smooth muscle fibers distributed in two layers: a longitudinal inner sublayer and a circular outer sublayer, different from the findings in muscle tissue arteries, with a single, circularly arranged muscle layer. This arrangement could be related to testicular temperature homeostasis by reducing the temperature of the testis and seminiferous tubules. The results described in this work suggest that these anatomical adaptations may be very significant in the face of the constant increase in global temperature. Further and better research is required to understand the mechanisms of thermoregulation in human reproduction and the histological particularities of the tissues that form the scrotum. RESEARCH HIGHLIGHTS: The human scrotal artery has a histological composition adapted for regulation of testicular temperature. The muscular double middle layer of the scrotal artery retains intravascular temperature.


Assuntos
Túnica Adventícia , Escroto , Masculino , Adulto , Humanos , Escroto/fisiologia , Biodiversidade , Temperatura , Testículo/fisiologia , Artérias/fisiologia , Regulação da Temperatura Corporal/fisiologia
2.
J. health med. sci. (Print) ; 8(3): 141-148, jul.2022. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1442512

RESUMO

INTRODUCCIÓN La telerradiología se basa en el despliegue de radiólogos a distancia para evaluar estudios de dicha especialidad. Actualmente hay evidencia limitada sobre las tasas de error de evaluaciones en telerradiología. Este estudio corresponde a una revisión de las discrepancias entre los informes preliminares y finales de tomografía computada (TC) de una unidad de urgencia telerradiológica. OBJETIVO Determinar las discrepancias de las reevaluaciones (addendum) en los informes radiológicos de TC en una unidad de telerradiología de urgencia. MATERIALES Y MÉTODOS La recolección de datos se planificó a modo de tabla de cotejo, en la cual se tabularon casos de reevaluaciones de urgencia desde el mes de enero hasta mayo del año 2021, en base a la categorización Agrawal. RESULTADOS De una total de 111.599, 836 informes presentaron addendum, que corresponden al 0,74% del total informado, La categoría Agrawal 0 agrupó la mayor cantidad de casos y los exámenes de TC especialidad de cuerpo se encuentran los segmentos con mayores requerimientos de reevaluación. Discusión: Los valores obtenidos permiten establecer una baja incidencia de reevaluaciones y de la gravedad de estas, apuntando a errores asociados a canales de comunicación, redacción y elaboración de informes con especial énfasis en estudios TC Tórax y Abdomen/Pelvis. CONCLUSIÓN El porcentaje de cumplimiento de un 99,26% de exactitud en los informes permite concluir la alta confiabilidad y la calidad del servicio de telerradiología de la empresa en cuestión durante el periodo evaluado y el empleo de medidas correctivas basadas en organización, gestión e instrumentalización tecnológica


Assuntos
Humanos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Telemedicina/estatística & dados numéricos , Serviços Médicos de Emergência/estatística & dados numéricos , Epidemiologia Descritiva
3.
Comput Methods Programs Biomed ; 117(2): 225-37, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25047567

RESUMO

Semen analysis is the first step in the evaluation of an infertile couple. Within this process, an accurate and objective morphological analysis becomes more critical as it is based on the correct detection and segmentation of human sperm components. In this paper, we present an improved two-stage framework for detection and segmentation of human sperm head characteristics (including acrosome and nucleus) that uses three different color spaces. The first stage detects regions of interest that define sperm heads, using k-means, then candidate heads are refined using mathematical morphology. In the second stage, we work on each region of interest to segment accurately the sperm head as well as nucleus and acrosome, using clustering and histogram statistical analysis techniques. Our proposal is also characterized by being fully automatic, where a user intervention is not required. Our experimental evaluation shows that our proposed method outperforms the state-of-the-art. This is supported by the results of different evaluation metrics. In addition, we propose a gold-standard built with the cooperation of a referent expert in the field, aiming to compare methods for detecting and segmenting sperm cells. Our results achieve notable improvement getting above 98% in the sperm head detection process at the expense of having significantly fewer false positives obtained by the state-of-the-art method. Our results also show an accurate head, acrosome and nucleus segmentation achieving over 80% overlapping against hand-segmented gold-standard. Our method achieves higher Dice coefficient, lower Hausdorff distance and less dispersion with respect to the results achieved by the state-of-the-art method.


Assuntos
Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/normas , Microscopia/métodos , Microscopia/normas , Reconhecimento Automatizado de Padrão/normas , Análise do Sêmen/normas , Cabeça do Espermatozoide/ultraestrutura , Inteligência Artificial , Células Cultivadas , Chile , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Reconhecimento Automatizado de Padrão/métodos , Padrões de Referência , Reprodutibilidade dos Testes , Análise do Sêmen/métodos , Sensibilidade e Especificidade
6.
Environ Sci Pollut Res Int ; 18(3): 497-502, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20865341

RESUMO

INTRODUCTION AND AIMS: The Chilean Altiplano ecosystem is conserved free from contaminants and pollutants because of the absence of major local human activities such as agriculture or other industries. We studied the effects of paraoxon on proliferation and apoptosis of testicular cells during active spermatogenesis in Dugesia gonocephala collected from a pristine river (Guacollo) in the Altiplano region nearby Visviri town, Chile. MATERIALS AND METHODS: Adult planarians were incubated in varying concentrations of paraoxon (0.8, 0.4, 0.04, 0.004, and 0.0004 mM) for 4 h. After 3 h of incubation, bromodeoxyuridine (BrdU) was added. Effects on cell proliferation (BrdU) and apoptosis (Apaf-1) were determined by immunohistochemistry. RESULTS: Paraoxon concentrations of 0.4 and 0.8 mM caused 100% mortality in the respective treatment groups. The lowest tested concentration (0.0004 mM) caused a significant increase on cell proliferation in the seminiferous tubules, as well as an increase in the number of apoptotic cells. All other tested concentrations significantly inhibited cell proliferation and induced apoptosis. CONCLUSIONS: Paraoxon inhibits DNA synthesis and induces apoptosis during spermatogenesis in adult planarians from a high-altitude, pollution-free environment. This could suggest its use as a biosensor or biomarker for contamination with agro pesticides.


Assuntos
Inseticidas/toxicidade , Paraoxon/toxicidade , Planárias/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Apoptose/efeitos dos fármacos , Fator Apoptótico 1 Ativador de Proteases/metabolismo , Bromodesoxiuridina/metabolismo , Proliferação de Células/efeitos dos fármacos , Chile , Água Doce/química , Inseticidas/análise , Paraoxon/análise , Planárias/metabolismo , Poluentes Químicos da Água/análise
8.
Am J Physiol Endocrinol Metab ; 299(6): E998-E1005, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20858754

RESUMO

Exposure to excess testosterone (T) during fetal life has a profound impact on the metabolic and reproductive functions in the female's postnatal life. However, less is known about the effects of excess testosterone in males. The aim of the present study was to evaluate the impact (consequences) of an excess of T during fetal development on mature male testis. The testicular evaluation was by histological analysis and by determination of mRNA expression of the FSH receptor (FSH-R), transforming growth factor-ß type I receptor (TßR-I), and two members of the TGF-ß superfamily, transforming growth factor-ß3 (TGFß3) and anti-Müllerian hormone (AMH) in males born to mothers receiving an excess of T during pregnancy. At 42 wk of age, postpubertal males born to mothers treated with 30 mg of T propionate twice weekly from day 30 to 90, followed by 40 mg of T propionate from day 90 to 120 of pregnancy (T males), showed higher concentrations of FSH in response to a GnRH analog, a higher number of Sertoli cells/seminiferous tubule cross-section, and a lower number of germ cells/tubules (P < 0.05) than control males (C males) born to mothers treated with the vehicle. The mRNA expression of FSH-R and of TßR-I was higher in T males compared with C males (P < 0.05). Moreover, in T males, AMH expression level correlated negatively with the expression level of TGFß3. In C males, this latter correlation was not observed. These results suggest that prenatal exposure to an excess of T can negatively modify some histological and molecular characteristics of the mature testis.


Assuntos
Células Germinativas/metabolismo , Efeitos Tardios da Exposição Pré-Natal , Receptores do FSH/metabolismo , Células de Sertoli/metabolismo , Testículo/metabolismo , Testosterona/metabolismo , Análise de Variância , Animais , Contagem de Células , Feminino , Hormônio Foliculoestimulante/sangue , Células Germinativas/citologia , Células Germinativas/efeitos dos fármacos , Leuprolida/farmacologia , Masculino , Troca Materno-Fetal , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Radioimunoensaio , Receptores do FSH/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células de Sertoli/citologia , Células de Sertoli/efeitos dos fármacos , Ovinos , Testículo/efeitos dos fármacos , Testosterona/farmacologia
9.
Rev. chil. tecnol. méd ; 30(1): 1545-1550, 2010. ilus
Artigo em Espanhol | LILACS | ID: lil-572126

RESUMO

El conducto deferente humano presenta una pared muscular gruesa, donde el componente muscular liso ocupa la parte media y más prominente. Esta composición histológica le permite al órgano desarrollar las potentes contracciones durante el proceso de la eyaculación y emisión del semen. Objetivos: Analizar la presencia y distribución de la positividad inmunohistoquímica a Neurofilamentos (NF) en las paredes del conducto deferente humano. Pacientes, Materiales y Método: De tres pacientes sometidos a orquiectomía radical por diagnóstico de Seminoma, se obtuvieron los conductos deferentes fijados en formol tamponado (pH 7,2). Mediante procedimientos histológicos de rutina, se obtuvieron secciones de 5 um de espesor en portaobjetos silanizados. Se procedió al desarrollo del protocolo de inmunohistoquímica usando anticuerpos específicos contra Neurofilamentos (NF); las imágenes se obtuvieron con cámara fotográfica digital CCD Micrometrics, en microscopio óptico Olympus CX31. Resultados: En los subcompartimientos de las secciones transversales de la pared de los conductos deferentes humanos, se observa la reacción inmunohistoquímica positiva a NF. Sin embargo, los fascículos nerviosos se concentran en la adventicia, mientras que en la mucosa y pared muscular son en extremo escasos y finos. Conclusión: En el conducto deferente existe una inervación preferencial dispuesta en la adventicia del órgano, siendo posible que la potencia de la contracción de la pared en base a la actividad muscular, requiera factores adicionales de estimulación.


The human vas deferens has a thick muscular wall, where the smooth muscle component occupies the middle and most prominent. This composition allows the organ histologic develop powerful contractions during ejaculation process and the semen. Objectives. To analyze the presence and distribution of immunologically positlve for Neurofilament (NF) on the walls of human vas deferens. Patients, Materiall and Methods.' Three patients undergoing radical orchiectomy for seminoma diagnosis were obtained vas deferens fixed in buffered formain (pH 12). By routine histological procedures, sections were obtained 5 um thick on silylated slides. We proceeded to the development of immunohistochemical protocol using specific antibodies against Neurofilament (NF); the digitized images were obtained with CCO Micrometrics digital camera, in the light microscope Olympus CX31. Results: In the subcompartments of the cross sections of the wall of human vas deferens, there is a positive immunohistochemical reaction to NF However, nerve bundles are concentrated in the adventitia, whereas in the mucosa and muscle wall are extremely rare and fine. Conclusion: In the vas deferens there willing preferential innervation in the adventitia of the court, it being possible for the power of contraction of the wall of the body based on muscle activity, stimulation requires additional factors.


Assuntos
Humanos , Adulto , Ducto Deferente/inervação , Ducto Deferente/imunologia , Ducto Deferente/ultraestrutura , Imuno-Histoquímica , Proteínas de Neurofilamentos/imunologia
10.
Int. j. morphol ; 25(2): 245-248, jun. 2007. tab
Artigo em Espanhol | LILACS | ID: lil-495949

RESUMO

Los agropesticidas organofosforados (OF) son ampliamente usados para incrementar la producción alimentaría. Sin embargo, se ha demostrado que inducen alteraciones a nivel testicular, relacionadas con la disminución de la fertilidad tanto en humanos como en animales. Por otra parte, diferentes estudios han sido llevados a cabo para desarrollar compuestos químicos o naturales que puedan inducir un efecto antagónico sobre los OF. En estudios anteriores, un extracto de una planta de los Andes peruanos (Maca) ha sido reconocido por su acción estimulante sobre la espermatogénesis. En el presente trabajo se estudiaron los efectos de ambos agentes externos sobre el testículo. Una población de 52 ratones machos adultos de la cepa CF1 fue dividida al azar en 4 grupos (Control, Malation, Maca, Malation-Maca), con intervalos de sacrificio de 1, 7, 14 y 21 días. Para analizar el grado de alteración inducida por estos agentes, se utilizaron técnicas de histomorfometría con ayuda del programa Image tools 3.1, en secciones testiculares. Nuestros resultados muestran que la altura del epitelio aumentó al día 1 en el grupo tratado con malation, cayendo al día 7 y llegando a valores similares al control, al día 14. Sin embargo, el grupo Malation-Maca no mostró cambios significativos. El lumen tubular, disminuyó al día 7 y 14, para normalizarse al día 21 en el grupo Malation. Sin embargo, en el grupo Malation-Maca el lumen tubular sólo bajó al día 14. El diámetro tubular disminuyó a los días 7 (p < 0.01), 14 y 21 en el grupo Malation, con respecto al control (p< 0.05). Sin embargo, el grupo Malation-Maca mostró valores normales. En conclusión, es posible establecer que el daño inducido por Malation es revertido al día 21 post administración de maca.


Organophosphoric (OP) agropesticidas are amply used to increase food production. However, it has been verified that they induce alterations at testicular level related to the diminution of fertility in humans as in animals. On the other hand, different studies have been made to develop chemical or natural compounds that can induce an antagonistic effect to OP. In previous studies an extract from a plant, from the Peruvian Andes (Maca) has been recognized by its stimulating action on spermatogenesis. In the present study the effects of both external agents were evaluated on testicular sections of testis of adult male mice on a population of 52 mice CF1, divided at random in 4 groups (Control, Malathion, Maca, Malathion-Maca), with sacrifice intervals of 1,7, 14 and 21 days. By means of morphometric technique and using the "Image Tools 3,1" software, the histology of testicular sections was evaluated, to analyze the degree of alteration induced by these agents. The epithelial height mainly has a rise in day 1, for Malathion group and then fall to day 7 to be normal by day 14. However, Malathion-Maca groups show no changes. The tubular lumen decreases at day 7 and day 14 to be normal by day 21 in Malathion group. However, in Malathion - Maca group, the tubular lumen decreases only at 14 days. The tubular diameter, at day 7 (p<0.01), 14 and 21 in Malathion group decreases respect to control (p<0.05), However, Malathion-Maca groups show normal values. In conclusion, it is possible to establish that the damage induced by Malathion is reverted by 21 days post-administration of Maca.


Assuntos
Masculino , Animais , Camundongos , Espermatogênese , Lepidium , Malation/farmacocinética , Preparações de Plantas/administração & dosagem , Testículo/anatomia & histologia , Testículo , Infertilidade Masculina/induzido quimicamente , Inseticidas Organofosforados/efeitos adversos , Malation/administração & dosagem , Malation/toxicidade
11.
Int. j. morphol ; 24(3): 481-488, sept. 2006. ilus
Artigo em Inglês | LILACS | ID: lil-474616

RESUMO

La disminución del aporte de O2 a los tejidos provoca daños de éstos, incluido el epitelio seminífero. Últimamente, se ha incrementado la población que trabaja a gran altura, interesando así el estudio de la hipoxia hipobárica sobre la espermatogénesis. Para este estudio se utilizaron dos grupos de ratones machos sexualmente maduros: Control (540 metros sobre el nivel del mar (msnm)) y grupo con hipoxia hipobárica simulada crónica (HHSC) (4.600 msnm) expuestos por 8, 16, 24 ó 33 días. Fueron evaluados hematocrito, reticulocitosis, peso de testículos, epidídimos y vesícula seminal; altura del epitelio seminífero, diámetro tubular, recuento y morfología espermática y lipoperoxidación de membranas de espermatozoides y parénquima testicular. El peso de testículos, epidídimos y vesícula seminal se redujo para empezar a recuperarse a los 33 días. El diámetro tubular y la altura del epitelio se redujeron y luego tendieron a aumentar sin normalizarse. El recuento y la morfología espermáticos fluctaron en el tiempo. Se puede concluir que la exposición a HHSC induce daño del epitelio seminífero, disminución de la lipoperoxidación en espermatozoides y tejido testicular, y altera la morfología testicular y espermática.


Reduction of O2 delivery to tissues damage them, including the seminiferous epithelium. Recently, population working in high altitude has increased, so that the study of hypobaric hypoxia on spermatogenesis becomes of interest. In this study we used two groups of male, sexually mature mice Control (C) (540 meters above sea level (masl)) and chronic simulated hypobaric hypoxia (CSHH) (4,600 masl) exposed during 8, 16, 24 or 33 days. Hematocrit; reticulocytosis; testicular, epididymal and seminal vesicle weight; seminiferous epithelium height, tubular diameter, sperm count and morphology and testicular parenchyme and spermatozoa membranes lipoperoxidation were measured. Weight of testis, epididymis and seminal vesicle were reduced but they recuperate at 33 days. Tubular diameter and epithelial height are reduced, subsequently they tend to increase without returning to normal values. The count and sperm morphology fluctuate along the exposure time. Lipoperoxidation levels of spermatozoa and testicular parenchyme are reduced. Therefore, we can conclude that exposure to CSHH induce damage in the seminiferous epithelium, decrease of lipoperoxidation in spermatozoa and testicular tissue, and damages the testicular and sperm morphology.


Assuntos
Animais , Masculino , Adulto , Camundongos , Epitélio Seminífero/anatomia & histologia , Epitélio Seminífero/crescimento & desenvolvimento , Epitélio Seminífero/irrigação sanguínea , Epitélio Seminífero/ultraestrutura , Hipóxia Celular/fisiologia , Espermatogênese/fisiologia , Camundongos
12.
Int. j. morphol ; 24(2): 171-174, jun. 2006. tab
Artigo em Inglês | LILACS | ID: lil-432796

RESUMO

RESUMEN: La espermatogénesis está regulada por el eje hipotálamo-hipófisis-gónada, y los andrógenos juegan un rol fundamental en sus últimas etapas. La administración del antiandrógeno flutamida interfiere con ella y con la función de órganos andrógeno dependientes (próstata (P) y vesícula seminal (VS)). En este estudio se inyectó flutamida (10 mg/Kg peso corporal) a 10 ratones y vehículo al control(n=6). Los ratones se sacrificaron a las 24(n=5) y 72(n=5) horas. En cortes de testículo se midió el diámetro del túbulo (TD) y la altura del epitelio (EH). P y VS se maceraron, y se determinaron las concentraciones de fructosa (VS) y zinc (P). No existe diferencia significativa en el TD entre los grupos. Sin embargo, el grupo de 72 h presenta menor EH respecto al control (p<0.01). La fructosa es menor sólo a las 72 h (p<0.01), intervalo en el cual se presenta la mayor concentración de zinc (p<0.01). La disminución de la EH se explicaría por el desprendimiento de las espermátidas elongadas, debido al bloqueo del efecto de la testosterona, sin reflejarse en el TD a intervalo corto. La disminución de fructosa refleja claramente la deprivación de andrógenos, en tanto que la concentración prostática aumentada a 72 hrs sugiere deficiencia en la secreción de zinc.


Assuntos
Animais , Masculino , Lactente , Camundongos , Espermatogênese , Flutamida/administração & dosagem , Flutamida/farmacologia , Glândulas Seminais/anatomia & histologia , Glândulas Seminais , Glândulas Seminais/metabolismo , Próstata/anatomia & histologia , Próstata , Próstata/metabolismo
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