918 resultados para Hepatocytes morphology


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The high consumption of fructose is linked to the increase in various characteristics of the metabolic syndrome. Fish oil is beneficial for the treatment of these comorbidities, such as insulin resistance, dyslipidemia, and hepatic steatosis. The objective of this study was to evaluate the consequences of the administration of fish oil concomitant to fructose ingestion during the experiment (45 days) and during the final 15 days in high-fructose-fed rats. Male Wistar rats were divided into 5 groups: control; those receiving 10% fish oil (FO); those receiving 60% fructose (Fr); those receiving 60% fructose and 10% fish oil for 45 days (FrFO); and those receiving fructose plus soybean oil for 30 days and fish oil for the final 15 days of the study (FrFO15). There was an increase in triacylglycerol, serum total cholesterol, and hepatic volume in the Fr group. The FO and FrFO groups experienced an increase in lipid peroxidation and a decrease in serum reduced glutathione. The FrFO group suffered greater hepatic injury, with increased alanine aminotransferase levels and DNA damage. Marked n-3 incorporation occurred in the groups receiving fish oil, favoring a better response to the oral glucose tolerance test. Fructose induced comorbidities of the metabolic syndrome, and the use of fish oil promoted a better glucose tolerance, although it was accompanied by more hepatocyte damage.

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Mannheimsia conica, sp. nov., is described, M. stricta redescribed and the hypopygial morphology including the phallus of all four Mannheimsia species is illustrated and discussed. A table with the different phallus terminology used in the main studies of this structure in Phoridae is presented. Uniformization of phallus terminology is suggested.

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Species of Smilax,, also known as greenbrier, are widely distributed in Brazil and their commercial trades are carried out by the extractivism of native species. We the aim to provide information about the germination and development of seedlings in four Smilax species, different experiments were developed under controlled conditions. We evaluated two germination treatments: temperature (30 degrees C and 20-30 degrees C) and light (presence/absence), and for few cases the tetrazolium treatment was applied. A different treatment response was observed among the studied species. Light had a significant influence in S. brasiliensis, with the highest germination rates at 20-30 C in dark conditions. S. campestris showed significant differences among temperature treatments, but not to light; while S. cissoides showed high germination rates (66-78%), independently of treatment. However, S. polyantha had low germination rates (19-24%). After one year, the expanded leaves showed different characteristics among the studied species. Leaves of S. brasiliensis were ovate, coriaceous, three main veins and prickle-like structures only on the midrib on abaxial face. S. campestris leaves were oblong, coriaceous and prickle-like structures were located at the leaf midrib and margin. S. cissoides had ovate-elliptic, membranaceous leaves, with three main veins with prickle-like structures on the abaxial face. S. polyantha leaves showed ovate-elliptic. coriaceous leaves, with three main veins, translucent secondary veins and no prickle-like structures. A seedling identification key was elaborated based on morphological characteristics. Rev. Biol. Trop. 60 (1): 495-504. Epub 2012 March 01.

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This research aimed to describe the macroscopic and microscopic liver of tambaqui, Colossoma macropomum, Teleost freshwater Family Characidae, of great economic interest for the Amazon basin. We used six juveniles aged between six month and one year, from the small holding Esteio, Alta Floresta/MT, that develops mainly fish farming. The body was photographed in situ, described macroscopically, and fragments were removed and processed by routine histological techniques through paraffin embedding and HE staining. The liver, located ventrally to the swim bladder and craniodorsally to the stomach, is brownish red and consisted of three lobes, the right lateral, the left lateral and the ventral lobe. Microscopically, the parenchyma consists of hepatocytes varying from irregular rounded hexagonal to round forms with a large and central nucleus, and arranged in linear strings limited by sinusoids and radiating to central veins, but with absence of liver lobules. The central veins are distributed throughout the parenchyma, while the portal space consists in most cases only of a hepatic vein and bile duct; elsewhere exist artery and duct. Formation of portal triads was not founde. Melano macrophages were frequently seen dispersed throughout the central parenchyma. The morphofunctional study of the digestive system of fishes of the Amazon basin is important to obtain knowledge about their weight gain, large scale production for human consumption and preservation of the species, and has also its importance for being used as bioindicators today.

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Plant mines are structures with the form of a cavity caused by consumption of host plant tissue by the insect's miner larvae. Plant mines are more common in leaves, but in Cipocereus minensis, a species in which the leaves are modified spines, the miner activity is restricted to the stem. The aim of this paper was to document the morphological and anatomical differences in the infected and uninfected stems of C. minensis due to the feeding habit of the mining agent. Fresh tissue samples of non-mined and mined young stem of C minensis were collected and examined in transverse sections. We hypothesize that the infection begins following mating when the females scratch the surface of the stem or while they feed on fruits and lay eggs, which subsequently develop into larvae, invading the cactus stem. The insect's miner larvae had mostly consumed the parenchyma tissue towards the center of the stem, and periderm formed along the entire path of the insect. This meristematic tissue or "wound periderm" is a common response for compartmentalization to isolate the damaged tissue, in this case the incubating chamber, in which the eggs will be placed. There were no signs of consumption of vascular tissue in the infested samples, further suggesting a compartmentalized infestation. The nest chamber was found in the stem pith region, with periderm surrounding an insect's miner pupa inside identified as a member of the Cerambycidae. The mining insect depends on a host plant to complete the life cycle; however, the nature of this partnership and the long-term effects of the insect on the plant tissue are unknown. The complex mechanisms by which herbivorous insects control the morphogenesis of the plant host are discussed. We propose that C. minensis has a recognition system to identify insect attack and evaluate the effectiveness of early response triggering compartmentalized defense mechanisms by protecting the injured area with a new layer of periderm.

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Background: The bovine yolk sac derives from visceral endoderm and its development occurs between days 18-23 of gestation. The study of this membrane is important for comparative data and has already been performed in rodents, sheep and in cattle, especially Bos taunts. In species Bos indicus the yolk sac has not quite been studied and is believed that there are morphological differences between these species. The yolk sac undergoes a process of involution and degeneration during embryonic development and none vestige of it is found in late gestation. The period in which occurs the involution of the yolk sac coincides with the period of increased pregnancy loss in cattle, and changes in the morphology of this membrane may indicate the reasons for such high loss rates. Thus, considering that the yolk sac is important for embryonic circulation and metabolic transmission, besides participating actively in the process of cattle placentation, this study aimed characterize morphologically the involution of the bovine yolk sac. Materials, Methods & Results: The early gestational period was determined between days 20 and 70 post-insemination (p.i), according to the exterior characteristics of embryo/fetus. For macroscopic analyzes the uterus was dissected to expose the fetal membranes and subsequently the embryo/fetus was photographed. The samples were fixed for light microscopy and transmission electron microscopy. The yolk sac that emerges from the ventral part of the embryo was prominent and composed by a central part with two thin peripheral projections of different lengths. The bovine yolk sac with about 9 cm on day 25 p. i. of pregnancy permanently decreased its total length during this study. Histologically, the yolk sac is composed of three cell layers: the mesothelium, the mesenchyme and the endoderm. In mesenchyme are found blood islets. In the endoderm are formed cells invaginations toward the mesenchyme originating small canaliculi. The ultrastructure of yolk cells presented many mitochondria, rough endoplasmic reticulum, vesicles, euchromatin and the presence of two nucleoli, Discussion: The real first blood circulation in the bovine is attached with the development of yolk sac, differently from other membranes, such as the corium, that does not present evidence of vascularization by the age of 20-30 days. The erythroblasts found in the yolk sac are related to vasculogenesis and the process of differentiation of blood cells during the erythropoiesis. It could be observed on the histology of the yolk sac, in embryos of 30-50 days old, the presence of canaliculi and small folds of the epithelium. The canaliculi collapse is associated with the degeneration of the endoderm wall of the yolk sac. The organelles present in the endoderm cells of the yolk sac are associated with the function of protein metabolism and in the exchange of substances between the mesenchyme and the mesothelium, For these findings, could be observed that the yolk sac epithelium is found active until the 50th day of gestation, and thereafter regresses. However, remnants of this membrane may be present until the 70th day, These features may represent a presence of an active chorionvitelline placenta in this period responsible for the maintenance of pregnancy whereas the chorioallantoic placenta is not definitively established.

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(Viability, production and morphology of pollen grains for different species in the genus Manihot (Euphorbiaceae)). The objective of this work was to characterize the viability, production and morphology of pollen for different species in the genus Manihot. Floral buds from Manihot accessions were collected from two germplasm banks at Embrapa Cassava & Fruits. The viability of the pollen was assessed via colorimetric, in vitro and in vivo assays. The diameter of the pollen grains was determined by measuring the transversal length of the grain. The experimental design was entirely randomized. Studies on pollen ultrastructure were performed via scanning electron microscopy. Pollen viability was high in the colorimetric tests and intermediate in vivo tests; there was no germination in the in vitro tests. The average production for all accessions was 1,253 pollen grains per floral bud. The size of the pollen grains varied from 132 to 163 pm in the wild accessions, and 129 to 146 pm in the cultivated accessions. The pollen grains for all accessions were very large, apolar, spherical as well as inaperturate, with an exine ornamented with pila organized in a Croton pattern. The wild accessions, in general, produced more and larger pollen grains compared with the cultivated accessions.

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Morphologic changes on copper surfaces upon applying an established potential protocol were examined by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The results showed a good correlation between the time employed in the electrode activation and the resulting microstructure and electrochemical activity.

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The scarcity of comprehensive characterizations of soils associated to gentle summit depressions of the Northeastern Brazilian Coastal Plains justifies this work, which had as objective to provide basic information for the more diverse agricultural and non-agricultural uses. For that, representative soils (Spodosols or similar soils) from these environments were selected in Alagoas, Sergipe and Bahia states. This approach included characterization of morphological, mineralogical and micromorphological properties of the soil profiles, employing standard procedures. The morphological characterization corroborated the effect of the podzolization process during the formation of these soils. The mineralogy of the clay fraction of these soils was basically composed of kaolinite and quartz, which, associated to the very sandy texture, helped in the understanding of the obtained data. The soil micromorphological study, besides confirming the field morphology, mainly in regard to the strong cementation, aggregated value to the work in terms of the secure identification of the clay illuviation process (non-identified in the field), in association with the dominant podzolization process.

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Non-destructive procedures are desirable for a precise internal seed morphology assessment. In this research the efficiency of X-ray densitometry for internal seed morphology analysis and physical quality of squash, melon and watermelon was evaluated. Seeds were submitted to X-ray densitometry and a typical density profile for each seed was generated. Based on the detailed densitometry profiles it was possible indicate density values for specific seed regions of the seeds and identify causes of poor germination. X-ray densitometry was considered as a promising non-destructive procedure to evaluate internal seed morphology of squash, melon and watermelon and demonstrated a strong potential for further research in seed testing.

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Objective. - The aim of this study was to identify the effects of strength training on plasma parameters, body composition and the liver of ovariectomized rats. Methods. - Wistar sedentary (SHAM), ovariectomized (OVX), and ovariectomized trained rats (strength training [OVX-EXE]) of 85% of one maximal repetition (1 RM), three times per week, for 10 weeks, were used on this study. We monitored the body weight and visceral (uterine, mesenteric and retroperitoneal) and subcutaneous adiposity, total cholesterol, triglycerides, HDL, blood glucose and liver morphology to identify the presence of macrovesicular steotosis (haematoxylin and eosin staining). Results. - We observed that strength training changed body weight (SHAM 293.0 +/- 14.5 g; OVX 342.6 +/- 10.8 g; OVX-EXE 317.7 +/- 11.9 g, P < 0.05), visceral and subcutaneous adiposity, glucose (SHAM 111.2 +/- 10.0 mg/dL; OVX 147.4 +/- 18.8 mg/dL; OVX-EXE 118.5 +/- 2.2 mg/dL, P < 0.05), increased HDL (SHAM 82.7 +/- 1.4 mg/dL; OVX 64.6 +/- 2.8 mg/dL; OVX-EXE 91.4 +/- 2.6 mg/dL, P < 0.05) and reduced macrovesicular steatosis in liver tissue. Conclusions. - Considering the data obtained in this research, we emphasise the use of strength exercise training as a therapeutic means to combat or control the metabolic disturbances associated with menopause, including adiposity, and adverse changes in blood glucose, blood HDL and macrovesicular steatosis. (C) 2011 Elsevier Masson SAS. All rights reserved.

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In this work poly(hydroxybutyrate/poly(vinyl butyral)- co-(vinyl alcohol)-co(vinyl acetate) (or ethylene propylene diene monomer rubber) blends were prepared by conventional processing techniques (extrusion and injection moulding). A droplet type morphology was obtained for P(3HB)/PVB blends whereas P(3HB)/EPDM blends presented some extent of co-continuous morphology. In addition, rubbery domains were much smaller in the case of PVB. These differences in morphology are discussed taking into account solubility parameters and rheological behaviours of each component. For both blends, the increase of elastomer ratio led to a decrease of Young's modulus but an increase in elongation at break and impact strength. The latter increased more in the case of P(3HB)/EPDM blends although the rubbery domains were larger. These results are explained in the light of the glass transition of the rubber and the presence of plasticizer in the case of PVB. The addition of elastomer also resulted in an increase of P(3HB) biodegradation rate, especially in the case of EPDM. It is assumed that, in this case, the size and morphology of the rubbery domains induce a geometrical modification of the erosion front which leads to an increase of the interface between P(3HB) phase and the degradation medium and consequently to an apparently faster biodegradation kinetics of PHB/rubber blends. Copyright (C) 2011 Society of Chemical Industry

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Anadia pariaensis Rivas, La Marca, and Oliveros, 1999, and Anadia steyeri Nieden, 1914, are two particularly rare and poorly known lizards described from single specimens. In the case of A. pariaensis, it remains known from the holotype, whereas A. steyeri is known from three additional specimens reported in the literature after the original description of the species. A single new specimen of A. pariaensis and five of A. steyeri, including the first adult males recorded for both species, make possible a more representative description of both species, including descriptions of the hemipenes. Despite both species presenting some similar morphological characteristics, the examination of the hemipenial morphology revealed very different organs. The hemipenis of A. steyeri presents some characteristics that resemble the organs of two species from the Santa Marta Mountain Range in the "bitaeniata-group" (Anadia pulchella and Anadia altaserrania). On the other hand, the hemipenes of A. pariaensis are unique morphologically and cannot be associated with the hemipenes known from other species in the genus. We describe variation within both species, and we comment on possible sexual dimorphism (number and arrangement of the femoral pores), natural history, and the known geographic distribution of the species. We also comment on Anadia bumanguesa Rueda-Almonacid and Caicedo 2004 based on a new specimen, the second known. This species may be a synonym of A. steyeri.

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In this work, mesoporous titania is prepared by templating latex sphere arrays with four different sphere diameters at the micrometric scale (phi > 1 mu m). The mesoporous titania homogeneously covers the latex spheres and substrate, forming a thin coating characterized by N-2 adsorption isotherm, small angle X-rays scattering, atomic force, field emission and transmission electronic microscopies. Mesoporous titania has been templated into different shapes such as hollow particles and monoliths according to the amount of sol used to fill the voids of the close packed latex spheres. Titania topography strongly depends on the adsorption of polymeric segments over latex spheres surface, which could be decreased by changing the dimensions of latex spheres (phi = 9.5 mu m) generating a lamellar architecture. Thus, micrometric latex sphere arrays can be used to achieve new surface patterns for mesoporous materials via a fast and inexpensive chemical route for construction of functional devices in different technological fields such as energy conversion, inclusion chemistry and biomaterials. (C) 2011 Elsevier Inc. All rights reserved.

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Introduction: This study examined the anatomy of 4-rooted maxillary second molars by using micro computed tomography. Methods: Twenty-five 4-rooted maxillary second molars were scanned to evaluate the size and curvature of the roots; the distance and spatial configuration between some anatomical landmarks; the number of root canals and the position of apical foramina; the occurrence of fusion of roots and enamel pearls; the configuration of the canal at the apical third; the cross-sectional appearance, the volume, and surface area of the root canals. Data were compared by using analysis of variance post hoc Tukey test (alpha = 0.05). Results: The specimens were classified as types I (n = 16), II (n = 7), and III (n = 2). The size of the roots was similar (P > .05), and most of them presented straight with 1 canal, except the mesiobuccal that showed 2 canals in 24% of the samples. The configuration of the pulp chamber was mostly irregular quadrilateral-shaped. The lowest mean distance of the orifices was observed between the buccal roots (P < .05). Accessory canals were present mostly in the apical third. Location of the apical foramina varied considerably. Fusion of roots and enamel pearls occurred in 44% and 8% of the samples, respectively. Mean distance from the pulp chamber floor to the furcation was 2.15 +/- 0.57 mm. No statistical differences were found in the bi-dimensional and 3-dimensional analyses (P > .05). Conclusions: All analyzed parameters showed differences between roots, except for the length of the roots, the configuration of the canals at the apical third, cross-sectional appearance, volume, and surface area of the canals. (J Endod 2012;38:977-982)