Morphological study of the prostate gland in viscacha (Lagostomus maximus maximus) during periods of maximal and minimal reproductive activity.

The viscacha (Lagostomus maximus maximus) is a rodent with photoperiod-dependent seasonal reproduction. The aim of this work was to study the morphological variations of the prostate during periods of maximal (summer, long photoperiod) and minimal (winter, short photoperiod) reproductive activity. Prostates of adult male viscachas were studied by light and electron microscopy, immunohistochemistry for androgen receptor, and morphometric analysis.

Hydroxytyrosol and oleuropein of olive oil inhibit mast cell degranulation induced by immune and non-immune pathways.

The aim of this study was to determine whether hydroxytyrosol and oleuropein, the major phenols found in olives and olive oil, inhibit mast cell activation induced by immune and non-immune pathways. Purified peritoneal mast cells were preincubated in the presence of test compounds (hydroxytyrosol or oleuropein), before incubation with concanavalin A, compound 48/80 or calcium ionophore A23187. Dose-response and time-dependence studies were carried out.

Histological changes in the retina provoked by lithium treatment in a nocturnal rodent (Lagostomus maximus maximus).

Daily morphological variations have been previously described in the viscacha (Lagostomus maximus maximus) retina. The aim of this work was to determine the effects of lithium administration on the histology of retinas from this nocturnal rodent since lithium is a drug that has been shown to affect different parameters of circadian rhythms. Adult male viscachas were divided into 2 groups, injected daily with lithium chloride or vehicle for 35 days, and sacrificed at 08:00, 16:00, and 24:00 h for light and electron microscopy studies.

processing: Transparent visualization via data interception.

In situ visualization has become a popular method for avoiding the slowest component of many visualization pipelines: reading data from disk. Most previous in situ work has focused on achieving visualization scalability on par with simulation codes, or on the data movement concerns that become prevalent at extreme scales. In this work, we consider in situ analysis with respect to ease of use and programmability.

An Analysis of Scalable GPU-Based Ray-Guided Volume Rendering.

Volume rendering continues to be a critical method for analyzing large-scale scalar fields, in disciplines as diverse as biomedical engineering and computational fluid dynamics. Commodity desktop hardware has struggled to keep pace with data size increases, challenging modern visualization software to deliver responsive interactions for () algorithms such as volume rendering. We target the data type common in these domains: regularly-structured data.

Seasonal changes in the activity of the adrenal medulla of Viscacha (Lagostomus maximus maximus).

Animals living in nontropical climates modify their physiology and behavior to adapt to seasonal environmental changes. Part of this adaptation involves the release of catecholamine from sympathetic nerve endings and the adrenal medulla, which play a major role in regulating energy balance. The aim of this work was to investigate whether adult male viscachas in their natural habitat exhibits structural changes in the adrenal medulla during the annual seasonal cycle.

Evaluation of Interactive Visualization on Mobile Computing Platforms for Selection of Deep Brain Stimulation Parameters.

In recent years, there has been significant growth in the use of patient-specific models to predict the effects of neuromodulation therapies such as deep brain stimulation (DBS). However, translating these models from a research environment to the everyday clinical workflow has been a challenge, primarily due to the complexity of the models and the expertise required in specialized visualization software. In this paper, we deploy the interactive visualization system ImageVis3D Mobile, which has been designed for mobile computing devices such as the iPhone or iPad, in an evaluation environment to visualize models of Parkinson's disease patients who received DBS therapy.

Seasonal morphological variations and age-related changes of the seminal vesicle of viscacha (Lagostomus maximus maximus): an ultrastructural and immunohistochemical study.

The viscacha is a seasonal rodent that exhibit an annual reproductive cycle with periods of maximum reproductive activity and gonadal regression. We studied seasonal variations in the morphology and cellular population of the seminal vesicles (SVs) during both periods and in impuber animals. Seminal vesicles were studied by light and electronic microscopy.

Activation of human leukemic mast cell line LAD2 is modulated by dehydroleucodine and xanthatin.

The aim of the present study was to determine whether dehydroleucodine, xanthatin and 3-benzyloxymethyl-5H-furan-2-one inhibit the activation of human leukemic LAD2 mast cells induced by compound 48/80 or the calcium ionophore A23187. LAD2 cells were preincubated in the presence of test drugs and then challenged with the secretagogues. This study provides the first evidence in favor of the view that dehydroleucodine and xanthatin inhibit the degranulation of LAD2 cells, thus acting as human mast cell stabilizers.

Effect of the photoperiod and administration of melatonin on the pars tuberalis of viscacha (Lagostomus maximus maximus): an ultrastructural study.

The pituitary pars tuberalis (PT) is a glandular zone exhibiting well-defined structural characteristics. Morphologically, it is formed by specific secretory cells, folliculostellate cells, and migratory cells coming from the pars distalis. The purpose of this work was to investigate differences in specific cellular characteristics in the PT of viscachas captured in summer (long photoperiod) and winter (short photoperiod), as well as the effects of chronic melatonin administration in viscachas captured in summer and kept under long photoperiod.

Novel anti-ulcer alpha,beta-unsaturated lactones inhibit compound 48/80-induced mast cell degranulation.

The present study was designed to examine the effects of a sesquiterpene lactone isolated from Artemisia douglasiana Besser (dehydroleucodine), a xanthanolide sesquiterpene isolated from Xanthium cavanillesii Schouw (xanthatin) and a semisynthetic butenolide (3-benzyloxymethyl-5H-furan-2-one) on mast cell degranulation induced by compound 48/80. Peritoneal mast cells from male adult Sprague-Dawley rats were purified in Percoll, preincubated in the presence of test lactones (dehydroleucodine, xanthatin or 3-benzyloxymethyl-5H-furan-2-one) and then challenged with the mast cell activator compound 48/80 (10 microg/ml). Concentration-response and kinetic studies of mast cell serotonin release evoked by compound 48/80, evaluation of mast cell viability and morphology by light and electron microscopy, and comparative studies using ketotifen and sodium chromoglycate were carried out.

Ultrastructural and biochemical seasonal changes in epididymal corpus and cauda of viscacha (Lagostomus maximus maximus).

The reproductive and adaptative behavior of wild rodents is synchronized primarily by the photoperiod. The viscacha, a South American rodent of nocturnal habits and seasonal reproduction is photoperiod-dependent and its reproductive behavior is regulated by the retinohypothalamic-pituitary pineal axis. Adult males exhibit an annual reproductive cycle with periods of maximum gonadal activity (summer-early autumn) and gonadal regression (winter).

Morphological and endocrine study of the ovarian interstitial tissue of viscacha (Lagostomus maximus maximus).

The morphological and endocrine aspects of the ovarian interstitial tissue of adult female viscachas were investigated to establish the probable function and the biological significance of this compartment in this rodent. Pregnant and nonpregnant adult female viscachas were used. The histological characteristics, histochemical properties, and ultrastructural features of the interstitial tissue were studied.

Morphological and biochemical study of the pineal gland of pregnant and non-pregnant female vizcachas (Lagostomus maximus maximus).

Objectives: The morphological and biochemical aspects of the pineal gland of pregnant and non-pregnant female vizcachas were investigated to examine whether there is a relationship between the pregnancy and this gland.

Methods: Pregnant and non-pregnant adult female vizcachas were used. The ultrastructure of type I cell (dark and light pinealocytes) was studied.

Ultrastructural and immunocytochemical studies of the viscacha (Lagostomus maximus maximus) pituitary pars tuberalis.

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.

Comparison of Predicted-difference, Simple-difference, and Premorbid-estimation methodologies for evaluating IQ and memory score discrepancies.

Discrepancies between WAIS-III and WMS-III scores for a group of 39 males and 48 females with a history of TBI were examined using three methodologies: Predicted-difference, Simple-difference, and Premorbid-estimation methods. Overall, the Predicted-difference method tended to classify the fewest individuals as impaired based on statistical rarity of discrepancies (11-16% classified as impaired), while the regression-based Premorbid method tended to classify the fewest individuals as impaired based on clinical rarity of discrepancies (4-8% classified as impaired). Degree of agreement is reported and was substantial.

Effect of dehydroleucodine on histamine and serotonin release from mast cells in the isolated mouse jejunum.

Objective And Design: DhL, a lactone isolated from Artemisia douglasiana, prevents gastrointestinal damage elicited by necrosis-inducing agents and exhibits antiinflammatory action. This work examines the effect of DhL on compound 48/80-induced histamine and serotonin release in the isolated mouse jejunum, to determine whether DhL inhibits mediator release from mast cells at the enteric level.

Material: Thirty jejuna from male Balb-c mice were used for the studies.

Changes in duodenal mast cells in response to dehydroleucodine.

Introduction: Dehydroleucodine (DhL), a sesquiterpene lactone isolated from Artemisia douglasiana Besser, prevents gastroduodenal damage elicited by necrosis-inducing agents such as absolute ethanol. Changes in the number of mast cells or evidence of activation of the cells for mediator release have been observed in a wide spectrum of disease processes involving the gastrointestinal tract. In the present study we examined the effects of DhL on duodenal mast cell population and their histamine content, with the goal of throwing more light on the mechanism of action of the drug.

Daily morphological variations in the viscacha (Lagostomus maximus maximus) retina. Probable local modulatory action of melatonin.

Given that the local melatonin levels exhibit rhythmic daily changes in the retina of the viscacha, we considered it important to study the likely daily variations in morphology and specific 2-[(125)I]-iodomelatonin binding in retinas from this rodent and to correlate these putative changes with local indole levels. Adult animals of both sexes were captured in their habitat and were kept under a natural photoperiod. For light and electron microscopic studies the viscachas were sacrificed by decapitation at 08:00, 16:00, and 24:00 hr.

Ultrastructural and morphometric study of the Sertoli cell of the viscacha (Lagostomus maximus maximus) during the annual reproductive cycle.

Changes in the morphology of viscacha Sertoli cells were studied during the annual reproductive cycle. Sertoli cells exhibited marked nuclear and cytoplasmic changes. Seasonal variation in nuclear size and shape, chromatin texture, and nucleolus characteristics was observed.

Colloid in the pituitary pars distalis of viscacha (Lagostomus maximus maximus): ultrastructure and occurrence in relation to season, sex, and growth.

Randomly distributed extracellular colloidal accumulations were observed in the pars distalis of viscacha (Lagostomus maximus maximus). They were preferentially located in the peripheral zone of the gland and showed variability in shape and size. Two different types of colloidal accumulations were found by electron microscopy: 1) those surrounded by nongranulated follicular cells that correspond to characteristic follicles, and 2) those surrounded by granulated cells.

Stages of the cycle of the seminiferous epithelium of the viscacha (Lagostomus maximus maximus).

The adult male viscacha (Lagostomus maximus maximus) is a seasonal rodent. It exhibits a short period of testicular regression with partial arrest of spermatogenesis during winter (July-August). The present study provides the first description of the viscacha spermatogenic cycle during the period of maximum gonadal activity (summer-autumn).

Gastroduodenal mucosal protection induced by dehydroleucodine: mucus secretion and role of monoamines.

In previous work we have demonstrated that dehydroleucodine (DhL) prevents gastric damage induced by necrosis-inducing agents such as absolute ethanol (EtOH). In this study we examine the effects of DhL on gastroduodenal morphology and monoamine levels by histological and biochemical methods, respectively, as an approach to elucidating the cytoprotective mechanism of the drug. Histological evidence shows that DhL prevents formation of gastroduodenal mucosal lesions induced by EtOH and that this protective effect is related to the ability of the drug to stimulate mucus production.

Seasonal changes of the Leydig cells of viscacha (Lagostomus maximus maximus). A light and electron microscopy study.

The Leydig cells of viscacha (seasonal rodent) show cytoplasmic hypertrophy and regional distribution during the breeding period (summer-autumn). The dominant organelles are smooth endoplasmic reticulum (SER) and mitochondria. A moderately well-developed Golgi, abundant lipid inclusions, dense bodies like lysosomes in different stages, and centrioles are observed.

Lysosomal enzyme activity in rat adrenal gland related to the postnatal development.

The activity of five acid hydrolases in the adrenal gland at the perinatal stage in adult rats was measured here and changes in alpha-mannosidase and N-acetyl-beta-D- glucosaminidase activity were detected. These enzymes increase after birth reaching a peak between days 4 and 7. Other enzymes such as beta-glucuronidase, arylsulfatase and beta-glucosidase did not significantly change at the ages studied.