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The aim of the study was the examine atrophy and degenerative brain changes of nine elderly animals (three monkeys, two wild cats, a likaon, a bear, a fox and horse) and to find an animal model for researching Alzheimer disease in humans. Brain hemispheres were dissected into hemispheric slabs 4.0-4.8 mm thick. Tissue samples from the brains were fixed in 10% neutral formalin, and embedded in paraffin, and then stained with hematoxylin an eosin, Nissl method, and monoclonal antibody 4G8 mAb against b-polipeptyde and neurofibrillary tangles (NFT) were stained with anti-tau monoclonal antibody. The examined animals revealed various degrees of brain atrophy neuron loss in layer III-VI in particular, lipofuscin deposit, status lacunaris, degenerative changes in the white matter, and gliosis. Lafora-like bodies were observed in licaon, horse and bear brains. The monkeys, cats, licaon, foxes, with the exception of the horse developed brain parenchymal amyloidosis-b. Two types of plaque were present, with the diffuse form being predominant. Congophilic amyloid angiopathy was observed in all the animals with the exception of the horse. NFT and amyloidosis-b was observed only in the bear brain and the latter is a good model for Alzheimer's pathology.
The purpose of this study was to trace the immunoreactivity of the calcium binding protein calretinin in the periaqueductal gray matter of the midbrain of chinchillas. For this study the midbrains of five sexually mature male chinchillas were used. The immunoreactivity of this protein in this species has never been investigated up till now. The localization of its activity was examined by carrying out peroxidase-antiperoxidase (PAP) reaction using a mouse specific monoclonal antibody against calretinin. An intensive immunostaining for calretitin was observed in all the neurons in the dorsal and dorso-lateral periaqueductal gray matter. The results of the studies obtained suggest a similarity in the distribution of calretitin as seen in the neurons of periaqueductal gray matter of rats. This indicates that calretinin is involved in the regulation of intracellular calcium ion concentration. In this manner it can influence the proper functions of the neurons of the periaqueductal gray matter of the midbrain of the chinchilla.
Domesticated ruminants play a key role in world livestock production, while some other ruminant species are important in the hunting economy. Non-farm species kept in zoological gardens pose a new challenge for veterinarians. In addition, cervids are increasingly often maintained under farm conditions, in which it may be necessary to undertake medical interventions. The pattern of the brain base arteries is one of specific morphological features of species from the suborder Ruminantia, including the domestic cattle, zebu, buffalos, sheep, goats, reindeer and other deer species, giraffes, musk deer and antelopes. A specific feature of the arteries of the brain base in ruminants is the presence of the arterial nasal epidural rete mirabile, and in some species also the caudal epidural rete mirabile. In addition, in these animals the extracranial segment of the internal carotid artery obliterates, and as a consequence, blood flows into the brain by an alternative route from the maxillary artery, via the vasculature of the nasal epidural rete mirabile. It is widely accepted that the retia mirabilia in the system of head arteries in mammals are the anatomical basis of the so-called selective brain cooling. Essentially, this mechanism consists in cooling the warm blood expelled from the left ventricle during the contraction of the heart, which flows to the brain, creating a vast vasculature of the rete mirabile. It is encircled by a cooler blood, returning from the nasal cavity via the cavernous sinus. Retia mirabilia located on the brain base are the main effectors of heat dissipation and protection of the brain from overheating. This mechanism fits into the very current topic of animal welfare.
The aim of this study was to describe the structures and topography of the nuclei of the amygdaloid complex in chinchillas. The material for the study consisted of five chinchilla brains. The brains were fixed in formalin, dehydrated in ethyl alcohol and embedded in paraffin blocks. Next, the blocks were cut in the transversal plane into 12 µm-thick slices. The slices were coloured according to Klüver and Barrer's method and examined under a light microscope (OLYMPUS BX 40) equipped with the camera Color View IIIu Soft Imaging System. For the morphometric measurements, the program Cell^D Soft Imaging System (SIS) was used. One can distinguish three parts of the amygdala: corticomedial amygdaloid complex (CMC), basolateral complex (BLC) and other amygdaloid areas.( OA). The BLC is divided into three nuclei: lateral amygdaloid nucleus (LA), basolateral amygdaloid nucleus (BL) and basomedial amygdaloid nucleus (BM). The chinchilla's lateral amygdale (LA) is well developed and situated above the BL; laterally, it is bordered by the external capsule; the caudal pole of this nucleus constitutes at the same time the caudal pole of the amygdaloid complex. The basolateral amygdaloid nucleus in chinchillas is situated between the LA and BM. The basomedial amygdaloid nucleus is located ventromedially to the BM and dorsally to the cortical nucleus (CO). The corticomedial amygdaloid complex consists of the following: cortical nucleus (CO), medial nucleus (Me), central nucleus (CE), amygdalohippocampal area (AHA), the nucleus of the lateral olfactory tract (NLOT) and bed nucleus of the olfactory tract (BOAT). The nucleus of the lateral olfactory tract in chinchillas begins at the rostral part of the amygdala. It is bordered medially and dorsally by the anterior amygdaloid area (AAA) and laterally by the anterior part of the cortical nucleus. The chinchilla's bed nucleus of the olfactory tract is situated behind the NLOT. Dorsally, it borders on the ME, laterally on the CO. The central nucleus constitutes the dorsomedial part of the amygdala. The amygdalohippocampal area in chinchillas is located in the caudal part of the amygdala between the inferior horn of the lateral ventricle and CO. The chinchilla's cortical nucleus is a long band of neurons which constitutes the ventral part of the amygdala. The other amygdaloid areas include the anterior amygdaloid area (AAA) and intercalated nucleus (I) The intercalated nucleus consists of the group of neurons between the amygdala nuclei. The AAA constitutes the anterior pole of the chinchilla's amygdala.
The aim of the study was to investigate acetylcholinesterase-immunoreactive neurons in the CA1 area of the hippocampus and in the striatum (CS) of rats receiving rebaudioside A (RebA) for 15 days. RebA is a steviol glycoside used in the production of sweeteners, and it has been shown that glycosides affect memory and learning processes. RebA was administrated to adult rats for 15 days at 1 mg of glycoside/ml of water (group I) and 2 mg of glycoside/ml of water (group II). An indirect immunohistochemical peroxidase-antiperoxidase reaction was performed on frontal slides containing the hippocampus and CS with the use of a monoclonal antibody against AChE. Neurons immunoreactive for the protein were assessed morphologically and morphometrically in hippocampal area CA1 and in the CS. Microscopical observations did not reveal significant morphological changes in immunopositive neurons, which suggests that the glycoside had no neurotoxic effect of these cells. Morphometric analyses did not show changes in the density of AChE-immunoreactive neurons. On the other hand, a decrease in reaction intensity was demonstrated in hippocampal area CA1 in group I and in the CS in both groups of animals receiving RebA. The results of our preliminary studies suggest that RebA affects cholinergic neurons.
Using AAS, Pb, Cd, Zn, and Cu concentrations were measured in the brain, cerebrospinal fluid, liver, bile, and blood in 10 weeks old calves, 10 month old young beef cattle, and 10-12 years old cows. The lowest concentration of Cd was observed in claves' brain, the higher - in the cerebrospinal fluid, blood and bile, and the highest - in the liver. Cadmium content in tissues and body fluids of cows and young beef cattle, was found to be several times higher when compared with that determined in calves. Contrary to Pb and Cd, the highest concentrations of Cu were noted in the cerebrospinal fluid, liver and bile of calves when compared with those determined in young beef cattle and cows. Similarly, the highest levels of Zn were found in the liver, brain, bile and cerebrospinal fluid of calves in comparison with those determined in young beef cattle and cows.
Studies were carried out on 19 lambs and 7 adult sheep divided into 3 experimental groups. The first group (I) included lambs at the age from a few hours to 3 days of postnatal life, while the second group (II) - lambs from 2 to 4 weeks old. The third group (III) was composed of adult sheep. Concentrations of Pb, Cd, Zn, and Cu were measured in the homogenates of liver, brain, kidneys and skeletal muscles, using AAS. The highest Pb concentration was found in the liver of lambs from the group I, and the lowest - in the liver of adult sheep. Brain concentrations of Pb were the highest in lambs of group I, and the lowest - in lambs of group II. Similarly, the kidneys Pb content was the highest in lambs of group I, and slightly lower in older lambs (II) and adult sheep (III). The highest Cd concentration was found in the tissues of older lambs (II), and the lowest - in adult sheep (III). Cu and Zn concetrations did not show significant changes in the postnatal period, except for the liver in which the upward tendency was observed.
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