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In chronic liver disease, orthotopic transplantation is the only current therapeutic alternative but it is limited due to lack of donors. Trials with adult stem cells in acute liver damage show promising results. The aim of this work was to evaluate the effectiveness of human adipose stem cell (h-ASC)infusion in rats with chronic liver damage. Rats with thioacetamide-induced liver fibrosis were grouped into: group I control that did not receive thioacetamide and h-ASC, group II received thioacetamide and saline i.v., group III received thioacetamide and h-ASC 1 x 106/kg i.v. via tail vein. Histological liver regeneration was evaluated by METAVIR index, while Macrophagocytus stellatus (Kupffer cells), stellate cells a-SMA+ and collagen I+ cells by immunohistochemistry; functional damage was evaluated by blood levels of the analytes Aspartate Aminotransferase (AST), Alanine Aminotransferase (ALT), Alkaline Phosphatase (ALP), Urea and Blood Urea Nitrogen (BUN) and hemogram. The results show attenuation of structural liver damage evidenced by decreased nodules, degree of histologic injury on Metavir score, and decreased Macrophagocytus stellatus, a-SMA+ cells and type I+ collagen cells;functionally there is moderate reduction of AST, ALT, urea, BUN and moderate decrease of white cells but favorable effect on mean corpuscular volume and mean corpuscular hemoglobin. Eight weeks after infusion there is a small population of h-ASC in the liver. Inconclusion, intravenous infusion of h-ASC in rats reduces functional and structural damage of hepatic fibrosis with low persistence of h-ASC in the liver parenchyma. To our knowledge this is the first work that evaluates the effect of h-SC in the model of chronic murineliver damage and the persistence of transplanted cells. [ABSTRACT FROM AUTHOR]

Livers of Sprague Dawley rats were irradiated with daily doses of 6 J/cm² emitted by a laser AsGa, equivalent to . 904 nm during 15 days. Experiment animals were anaesthetised and killed after 5, 10, 30, 45 and 60 days post irradiation, in order to obtain samples of liver by surgery. These were processed for transmission electron microscopy, and morphometric techniques were applied using 8,500 X magnification with special emphasis on measuring the volumetric fractions of cell components in order to determine the duration of infrared stimulation. Analysis of the results between control hepatocytes and those irradiated with doses of 6 J/cm2 and by period after infra-red stimulation revealed the existence of marked differences between the volumetric fractions of cell components which determine cell function or are involved in protein synthesis. The measurements show clearly that the effect of the infrared laser persists up to 30 days post stimulation, with evidence of modifications of organelles revealing high functioning, while after 30 days a notable inhibition of this functioning is observed. It is therefore concluded that the effects of infrared radiation persist for precise times, provoking a drastic transformation in hepatocyte components, and thus the functioning of these high-metabolism cells. [ABSTRACT FROM AUTHOR]

During menopause, hormonal changes such as decreased estradiol and increased follicle stimulating and luteinizing hormones occur. In premenopausal women fibrosis and hepatic steatosis is less than in postmenopausal women and improves when hormone replacement therapy is administered. The aim of this study was to determine quantitative aspects of the liver of rats undergoing an experimental model of ovariectomy-induced menopause. We used 10 Sprague-Dawley (Rattus norvergicus) healthy adults. The rats were weighed and divided into two groups (bilateral oophorectomy = Group Ovx and control = Group Sham The animals were sacrificed at 60 days and the liver removed obtaining a piece of each liver. Five cuts were made of 4 micron and stained with HE. We analyzed five fields per slide. M42 test was used. Stereological parameters considered were as follows: Nv, Vv, Sv and total number (Tn) of hepatocytes and sinusoids. The average weight of Ovx and Sham group was 300.8 g and 285.8 g respectively. The Nv of hepatocytes of rats subjected to sham surgery (CS) and Ovx (CO) was 6.89 and 7.70 x105/mm³ x105/mm³, respectively. The Vv of CS and CO hepatocytes was 71.92% and 80.48%, respectively. SV and CO, CS hepatocytes was 260.61 mm²/ mm³ and 273.64 mm²/mm³, respectively. The average volume of CS livers was 8.40 mm³ and hepatocyte Tn averaged 5.79 x 106. The average volume was 9.28 mm³CO livers and Tn of 7.15 x 106 Regarding the sinusoids, the Nv in the liver CS and CO was 2.81 x 105/mm² and 2.64 x 105/mm³, respectively. The Vv of sinusoids in CS and CO was 16.74% and 16.46%, respectively. The sinusoids in rats Sv CS and CO was 49.40 mm²/mm³and 45.21 mm²/mm³, respectively. The sinusoids Tn CS and CO averaged 2.37 x 106 and 2.45 x 106, respectively. The lack of estrogen can cause fibrosis and hepatic steatosis as noted by other authors, but also changes in the organization and the proportion of the components of the liver, factors to consider during diagnosis and prognosis of liver disorders. [ABSTRACT FROM AUTHOR]

Sprague Dawley rat livers were irradiated with 8 and 16 J/cm² daily doses during 15 days from the AsGA laser. equivalent to 904 rim. Liver samples were surgically removed from rats previously anesthetized, then processed for electronic microscopic transmission and subsequently studied and subjected to morphometric techniques using 8.500 X enlargements with special emphasis on quantifying cellular component volumetric fractions. The result analysis of the hepatocytes irradiated with 8 and 16J/cm² doses revealed that there were marked differences between the volumetric fractions of cellular components that determine cellular functionality and protein synthesis, a quantification that clearly demonstrates that with a dose of 8 J/cm² the optimum stimuli is achieved in order to obtain high functionality, while with a dose of 16 J/cm² a notable reduction of that functionality is noted, concluding that the effects of specific infrared radiation doses provoke a drastic transformation of its components in hepatocytes, and therefore its functionality, activating or inhibiting it, and representing the effect of these stimulations over this elevated metabolism cellular type. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

While studies have been conducted in the liver of different species, there is little research on the guinea pig, a rodent of easy handling and used as an experimentation animal. The aim was to describe in the guinea pig liver, some histological and histochemical aspects, which would allow experimental studies to be carried out. We used seven male guinea pigs (Cavia porcellus) obtained from the Bioterium of the Universidad de La Frontera, Temuco, Chile. Samples were fixed in buffered formalin and processed for inclusion in paraplast. Serial thick of 5 μm were stained for histological and histochemical studies. The liver presented a lobular architecture vague borders and portal tracts consisting of vascular structures and canalicular bile. Parenchymal cords were composed of hepatocytes with a cuboidal to polygonal appearence, and radially distributed from the central lobular vein. It showed the presence of glucogen liver cells, and hemosiderin neutral mucins. The average diameter of hepatocytes was 17.25 μm and the nucleous was of 7.31 μm. The guinea pig liver shows similarities with other species, however, to determine morphological parameters, age, environmental conditions of animals, feeding, etc. must be considered. [ABSTRACT FROM AUTHOR]

The infrared lasser emitted by the Gallium Arsenide diode provides an adequate therapy for articular lessions due to their healing, analgesic, and anti-inflammatory powers. It also promotes at cellular level mitochondrial ATP synthesis, modulates Calcium channels and activate mitotic processes by increasing DNA and protein synthesis. To determine the effective doses which stimulates rat liver protein synthesis, several samples from normal and irradiated tissues to intensities of 1, 2, 4, 8, and 16 Joules/cm2 by 15 consecutive days were taken. These samples were later prepared and observed under transmission E.M. (10000X) and analyzed by morphometric studies, where volume and organelle distribution, such as nucleus, cytoplasm, endoplasmic reticulum, glycogen inclussions, nucleolus, eu and heterochromatin were accounted, together at nuclear-cytoplasmic relationships and the cellular and nuclear areas. Under comparison normal and irradiated hepatocytes presented a significative difference in all evaluated parameters. It can be concluded that at certain specific level of infrared irradiation, hepatocytes alter their morphology by modifyng those cellular components involved in protein sintesis. [ABSTRACT FROM AUTHOR]

El láser infrarrojo genera emisiones las cuales inducen en las células tanto una activa síntesis proteica como modulando síntesis de DNA, de ATP mitocondrial y de fibras colágenas, de igual manera generando activación de la proliferación celular, las concentraciones de calcio citoplasmático y la actividad de un número creciente de enzimas. De hígados de rata irradiados con dosis diarias de 6 Joules/cm² durante 15 días consecutivos y sacrificadas a los 5,10, 30,45 y 60 días post irradiación fueron obtenidas muestras de hepatocitos para posteriormente ser tratados con técnica para microscopía electrónica de transmisión obteniéndose micrografías con aumentos finales de 8.500 X, realizándose en ellas estudios morfométricos con el propósito de cuantificar las fracciones volumétricas de componentes celulares pertenecientes a estas células con la dosis infrarroja descrita y visualizar la persistencia de los efectos de dicha estimulación. Se evaluaron fracciones volumétricas de: Citoplasma, núcleo, Retículo Endoplasmático Rugoso, mitocondrias, inclusiones de glicógeno, eu y heterocromatina. Los resultados derivados del estudio morfométrico comparativo entre hepatocitos irradiados con 6 J/cm² y sacrificados con diferentes días post irradiación indican que existen marcadas diferencias cuantitativas en todos los componentes celulares evaluados y se concluye entonces que los efectos de las estimulaciones infrarrojas persisten hasta 30 días post irradiación, estadio en el que se visualiza una marcada actividad celular básicamente de los componentes celulares involucrados en síntesis proteica. De igual manera, por sobre esta etapa se observa una constante disminución en el volumen de dichos componentes celulares, situación que indica una sostenida disminución en la actividad celular. Comprobándose, por ende, que los efectos de radiaciones infrarrojas producen drásticas transformaciones de sus constituyentes durante un cierto período de tiempo y modulando la funcionalidad en este tipo celular de elevado metabolismo [ABSTRACT FROM AUTHOR]