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INTRODUCTION AND HYPOTHESIS: Diabetes mellitus (DM) during pregnancy is associated with high levels of urinary incontinence (UI) and pelvic floor muscle dysfunction. Mild DM can lead to changes in urethral striated muscle and extracellular matrix (ECM) in pregnant rats considering both structures as an entire system responsible for urinary continence. METHODS: Ninety-two female Wistar rats were distributed in four experimental groups: virgin, pregnant, diabetic, and diabetic pregnant. In adult life, parental nondiabetic female rats were mated with nondiabetic male rats to obtain newborns. At the first day of birth, newborns received citrate buffer (nondiabetic group) or streptozotocin 100 mg/kg body weight, subcutaneous route (mild DM group). At day 21 of the pregnancy, the rats were lethally anesthetized and the urethra and vagina were extracted as a unit. Urethral and vaginal sections were cut and analyzed by: (a) cytochemical staining for ECM and muscle structural components, (b) immunohistochemistry to identify fast- and slow-muscle fibers, and (c) transmission electron microscopy for ultrastructural analysis of urethral striated muscle. RESULTS: In comparison with the three control groups, variations in the urethral striated muscle and ECM from diabetic pregnant rats were observed including thinning, atrophy, fibrosis, increased area of blood vessels, mitochondria accumulation, increased lipid droplets, glycogen granules associated with colocalization of fast and slow fibers, and a steady decrease in the proportion of fast to slow fibers. CONCLUSIONS: Mild DM and pregnancy can lead to a time-dependent disorder and tissue remodeling in which the urethral striated muscle and ECM has a fundamental function.

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De ratas Sprague Dawley tanto normales como irradiadas con dosis diarias de 1, 2, 4, 8, y 16 J/cm2 durante 15 días emitidas por el láser AsGa equivalente a 904 nm previamente anestesiadas, fueron quirúrgicamente obtenidas muestras de hígado, las que posteriormente fueron procesadas para microscopía óptica, siendo estudiadas y sometidas a técnicas morfométricas utilizando aumentos de 1000X, con especial énfasis en cuantificar áreas de núcleos y nucleolos. El análisis de los resultados entre hepatocitos normales e irradiados revela que existen marcadas diferencias entre sus áreas tanto nucleares como nucleolares, concluyéndose que los efectos de estas dosis de radiación infrarroja provoca en los hepatocitos una drástica transformación en sus componentes y por ende en su funcionalidad, principalmente en la relativa a la síntesis proteica, representando el efecto de estas estimulaciones sobre este tipo celular de elevado metabolismo.

Liver samples were taken from previously anaesthetised Sprague Dawley rats, both normal and irradiated with daily doses of 1, 2, 4, 8, and 16 J/cm2 applied over 15 days by AsGa laser equivalent to 904 nm. These samples were then processed for optical microscopy. They were studied and subjected to morphometric techniques using 1000X magnification, placing special emphasis on the quantification of the areas of nuclei and nucleoli. An analytic comparison of the results between normal and irradiated hepatocytes reveals the existence of significant differences between both the nuclear and nucleolar areas studied, from which it is concluded that the effect of these doses of infrared radiation is to provoke a drastic transformation in the components of the hepatocytes, and therefore in their functioning, principally with respect to protein synthesis, and that this would be the effect of stimulation of this nature on this type of high-metabolism cell.

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The hypophyseal pars tuberalis (PT) has been the focus of numerous studies attempting to understand its physiological role in the reproductive regulation and modulation by the neuroendocrine system. Ultrastructural studies of the PT in a number of species have shown that it consists of a well-developed hypophyseal area with important secretory activity, demonstrated by the abundance of secretory granules in the cytoplasm and the marked blood irrigation. This article describes ultrastructural and immunocytochemical aspects of the PT in viscachas captured in their habitat. The cell types identified were PT-specific cells, agranulated cells, and Folliculostellate cells. PT-specific cells are divided into type I and II. Type I cells have cytoplasms with secretory granules of 150-500 nm diameter. The secretory granules of type II PT-specific cells are 65-200 nm in diameter. Both cellular types exhibit numerous nerve endings on the plasmatic membranes. Agranulated cells exhibit nuclei with lax chromatin, mitochondria, phagosomes, scarce Golgi complex, and rough endoplasmic reticulum. Folliculostellate cells exhibit an irregularly shaped and moderately condensed nucleus. All the described cellular types exhibit deposits of cytoplasmic glycogen. The immunocytochemical study revealed the presence of cells immunostained for LH-beta and FSH-beta in the PT caudal zone. ACTH was only detected in the zona tuberalis. No staining was observed with antiprolactin, anti-TSH-beta, and anti-GH sera. Folliculostellate cells exhibited staining with anti-S-100. The results demonstrate that the viscacha PT is a hypophyseal zone with specific cellular types, which exhibits evident secretory activity. The presence of nerve endings suggests neural control of the function of PT cells.

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Este estudio fue llevado a cabo con el propósito de estudiar las modificaciones epiteliales en un proceso de carcinogénesis, además, la variación en la presencia de mastocitos y glucógeno, producitdos por la aplicación de benzopireno bore la mucosa labial de ratones machos IBF1 (IOR/HAB x C57/BL). Se seleccionaron ratones de 4 a 6 semanas de edad y se les suministró comida y aguda ad libitum y se dividieron en tres grupos. El primer grupo fue tratado con benzo(a)pireno, el segundo con acetona y el tercero permaneció como control Se aplicaron 10 il de estas sustancias sobre la mucosa labial de los animales durante 44 semanas, tres veces por semana. Todos los animales se sacrificaron y se realizó disección del labio. Las muestras fueron fijadas en formalina neutra al 10 por ciento. Posteriormente, se procesaron por la técnica clásica de inclusión en parafina y se utilizaron tres coloraciones: H&E, PAS y azul de toluidina. Estas biopsias fueron examinadas a las semanas 6, 16, 32 y 44, siguiendo los parámetros propuestos por la OMS (Smith, C y J.J. Pindborg)(1). El grupo tratado con benzo(a)pireno presentó cáncer en la semana 44. Los cambios histológicos más sobresalientes en los diferentes estadios fueron la queratinización superficial, grosor epitelial y displasia previa a estadios neoplásicos. El glucógeno disminuyó hacia la semana 44. Se presentaron cambios en la presencia de mastocitos en el proceso de carcinogéensis química, aunque su papel no se comprende aún.

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Astrocytic subtypes in different cortical regions of injured human cerebral cortex of 22 patients with brain trauma, vascular anomalies and brain tumours have been examined by means of light microscopy and conventional transmission electron microscopy. The cortical biopsies of frontal, parietal and temporal cortex were examined to analyse the heterogeneous astrocytic response and characterize astrocytic population subtypes. Swollen clear and dense astrocytes, glycogen rich- and glycogen-depleted astrocytes, aged or lipofucsin rich-astrocytes and reactive, dark, hypertrophic astrocytes were identified. Clear and dense astrocytes displayed bundles of glial filaments and dense inclusion bodies. Glycogen-rich astrocytes exhibited an accumulation of beta type of monogranular glycogen granules, which disappear in the glycogen-depleted astrocytes, suggesting anoxic mobilization of glycogen stores during ischemia or anoxia. Lipofucsin rich astrocytes were mainly related with ageing processes, although their presence in young patients suggests also an injured related process. Dark astrocytes with phagocytic properties were found. They exhibited bundles of glial filaments. The astrocytic response depended upon the nature of cortical insult, extent of damage, time course of pathological lesion and affected cortical region.

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