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The aim of the research was to conduct morphometrical analysis during the process of maturation of nucleus amygdaloideum lateralis. The brain of domestic pigs of both sexes (taken during the following period of their life: from 7th to 15th week of intrauterine life, newborn animals, one-month and one-year-old animals) were used as the material for the examination. The brains were removed and processed conventionally by microscope. The preparations were colored according to Klüvera-Barrer’s method and according to Nissel. Histological preparations obtained in this way were used for morphometrical analysis of the neurons of the corpus amygdaloideum’s nucleus amygdaloideum lateralis. Morphometrical examinations were carried out by the Nikon Eclipse E-600 microscope compressed with a JVC TK-1380-E camera and a computer using morphometrical MULTI-SCAN-BASE 08.98 program. The examination comprised the following parameters: the section area of nervous cells and the area of cell nucleus in µm²; the nucleo-cellar rate in %; the average diameter of nervous cell in µm; the volume of nervous cells in µm³; the number of neurons per 1 mm²; the number of neurons per 1 mm³. Morphometrical observation showed that in the 9th week of fetal life the cells forming the primary corpus amygdaloideum are of identical shape and size. The size of cell area of this period of fetal life fluctuates around 45 µm². In the 11th week of fetal life cells of the nucleus amygdaloideum lateralis are densely arranged, they have oval or polyhedral shape and contain a small amount of cytoplasm pretty evenly stained, in which Nissel’s granules are visible. In the 12th week of a domestic pig’s life cells of the nucleus amygdaloideum lateralis have a polyhedral, oval or pyramidal shape. In the subsequent periods of fetal life and new born animals, the appearance of cells composing the nucleus amygdaloideum laterais does not significantly change. In case of nucleus amygdaloideum lateralis nucleo-cellular rate fluctuates between 51 and 60%. The value of this rate decreases during development and maturation of neurons. On the basis of the examined morphometrical parameters the author claims that the neurons attain morphological maturity at the end of fetal life.
The aim of this research was the development and maturation of neurons in the baso-lateral group of corpus amygdaloideum in pigs during the ontogenesis process. The brains of domestic pigs of both sexes (taken during the following periods of their lives: from 7th to 15th week of intrauterine life, newborn animals, one-month and one-year-old animals) were used as the material for the examination. The brains were removed and processed conventionally by the microscope. The basolateral group of corpus amygdaloideum in domestic pigs consists of nucleus amygdaloideum lateralis and nucleus amygdaloideum basalis-lateralis. In the 7th, 8th and 9th weeks of intrauterine life the primary corpus amygdaloideum is made up of a very large quantity of thickly arranged neuroblasts. Their nuclei are of spherical shape and the cell nucleus is surrounded by a very small quantity of cytoplasm. In the 10th, 11th and 12th weeks of intrauterine life the differentiation of the formerly homogenous cells takes place. The group, dorsally situated, is corpus amygdaloideum lateralis, while lying beneath it is corpus amygdaloideum basalislateralis. In the next period of intrauterine life and in newborn animals the appearance of nervous cells forming nucleus amygdaloideum lateralis and nucleus amygdaloideum basalis-lateralis does not change. One can say that the cells forming the above mentioned nuclei of corpus amygdaloideum in domestic pigs are already morphologically mature in newborn animals.
The aim of the study was a quantitative examination (morphometrical analysis) of neurons during the maturation process of amygdaloideum baso-lateralis nuclei. The brains of domestic pigs of both sexes (obtained from the following periods: 7th-15th week of intrauterine life, newborn animals, one-month and oneyear old animals) were the examination material. The brains were removed and examined conventionally by microscope. The preparations were dyed according to Kltivera-Barrer's method as well as the Nissel method. The histological preparations obtained in the above way were used to morphometrically analyze the neurons of the corpus amygdaloideum's nucleus amygdaloideum baso-lateralis. Morphometrical examinations were carried out using the Nikon Eclipse E-600 microscope compressed with a JVC TK-1380-E camera and a computer using the MULTI-SCAN-BASE 08,98 morphometrical program. The following parameters were examined: the cross-section of nerve cells and the area of cell nuclei in µm2, the percentage of the nuclei-cellar rate, and the average diameter of nervous cell in µm, the volume of nervous cell in µm3, the number of neurons per 1 mm2, and the number of neurons per 1 mm3. Morphometrical observations revealed that cells forming the primary corpus of amygdaloideum in week 9 of fetal life are identical in shape and size. The size of the cell area in the 9th week of fetal life oscillates around 45 µm2. These cells, homogenous in the previous periods, undergo considerable differentiation during week 11 of fetal life. Mass nucleus structures appear from homogenous cells, including amygdaloideum baso-lateralis nuclei. The examined morphometrical parameters infer that neurons become morphologically mature at the end of fetal life.
Because of its special function in the body, diseases of the central nervous system can be very dramatic, especially if they affect the centres controlling the most vital functions of the body. They can develop as primary diseases or as secondary diseases, i.e. complications of another disease, the focus of which is located outside the nervous system. Diseases of the nervous system may affect its peripheral part (inflammation of nerves, polyneuropathies, radicular syndrome) or its central part (neuroinfections, developmental anomalies, dementia, trauma, tumors, epilepsy, stroke). There are also neurological diseases causing simultaneous changes to the peripheral and central parts. They are demyelination diseases, such as multiple sclerosis and transverse myelitis. There are also diseases affecting the spinal cord selectively. Muscle diseases such as myasthenia and muscular dystrophy, in which disorders of neuromuscular transmission are observed, may also be considered as neurological diseases. There is also a group of neurological diseases in which mental disorders can occur. Such diseases include, most importantly, dementia (Alzheimer’s disease, dementia with Levy bodies, fronto-temporal dementia) and encephalopathies (metabolic, traumatic, ischemic). During later stages of a neurological disease, mental symptoms resulting directly from numerous injuries to the central nervous system may occur. Neurodegenerative diseases in domestic animals are quite rare. However, they represent a very important and very large group of diseases. Many of these degenerations are similar to diseases occurring in humans, which makes it possible to understand them better by carrying out research on animals. Unfortunately, in many cases all we know about these diseases are their clinical symptoms, pathological changes that occur in their course and conclusions drawn from genealogical examinations. The introduction of more recent examination methods and new instruments makes it possible to obtain increasingly detailed knowledge of these diseases on the molecular level and, above all, a better understanding of their causes. Neurodegenerative disorders are among the most life-altering diseases and are therefore very costly to society.
Post traumatic stress disorder (PTSD) is a psychiatric abnormality caused by a drastic traumatic event or extreme stress, that exceeds the capability to adapt. There are many papers reporting anatomical brain changes induced by trauma and extreme stress, not only in white matter but in gray matter as well. Extreme stress and trauma are connected with elevation of cortisol level, which may cause damage to the hippocampus and may interfere with the anatomy of the hippocampus as well as its microstructure and cell number. Stress may inhibit the hippocampal neuroregeneration as well as hippocampal neurogenesis and even induce neuronal death within the hippocampus. Diffusor tensor imaging (DTI) is a powerful method enabling the visualization of the microstructure integrity of white matter, to evaluate the changes (rate and directionality) of water diffusion within myelin tracts and provide enhanced images of white matter tracts compared to traditional MRI morphometry images. One can evaluate the differences in white matter using fractional anisotropy (FA), which is a scalar metric of the degree of anisotropy and diffusion direction of water molecules, indicating fiber density, mylination and axon diameter. Many studies report reduced gray matter volume caused by extreme stress or trauma in people both with the diagnosis of PTSD as well as stress-exposed non PTSD in comparison to healthy controls. Studies have revealed reduced volume mostly in the hippocampus but also in regions such as anterior cingulate, corpus callosum, insula, septum pellucidum, subcallosal cortex, amygdala, prefrontal cortex and total brain volume. The right hippocampus may be prone to the effect of stress much more than the left hippocampus. Moreover, comparing trauma-exposed non-PTSD and PTSD participants, they have found volumetric abnormalities only within the right hippocampus among the PTSD group. They suggest an additional pathological process underlying PTSD, connected with the right hippocampus volume.
The aim the study was to discover the structure and topography of formatio hippocampi in chinchillas (Chinchilla brevicaudata). Investigations were carried out on the brains of 5 chinchillas. The material was preserved in buffered 10% formalin, and then dehydrated in ethyl alcohol of rising concentrations, embedded in paraffin blocks and cut transversally into 12 micrometer-thick sections. The sections were then stained according to Klüver and Barreras method. The formatio hippocampi, classified as a part of the rhinencephalon, are located in the medial part of the cerebral hemisphere, and indents in an arch into the light of the lateral ventricle. In the case of chinchillas the fomatio hippocampus consists of the hippocampus and dentate areas and the following cortical nervous structure: subiculum and four areas from CA1 to CA4. Formatio hippocampi as a cortical structure has a laminar build. The following layers may be distinguished in the subiculum: the marginal layer and cellular layer I and II. The structure of CA1, CA2, CA3, CA4 areas contains the following layers: stratum oriens, stratum pyramidal, stratum radiatum, and stratum molecular. The dentate area is a part of the formatio hippocampi formed by the gyrus dentatus and hilus fasciae dentate. Gyrus dentatus as a cortical structure has a laminar build. It is made up of two layers: molecular stratum and granular stratum.
The aim of the study was to evaluate selected morphometric parameters of three types of oligodendrocytes on the basis of their morphology. A total of ten male Wistar rats in two age groups, 25 weeks and 140 weeks, were used for the experiments. After the rats were sacrificed by perfusion-fixation, the midbrains with the periaqueductal grey matter were collected and embedded in celloidin. Semi-thin sections were stained with methylene blue, analysed and photographed under a light microscope. The morphometric parameters taken into account were mean cell size, mean perimeter of soma in µm and mean area of soma in µm2 . In addition, the percentages of different types of oligodendrocytes in the measurement area were determined. The results obtained were analysed statistically. In the PAG of the 25-week-old rats oligodendrocytes with light cytoplasm predominated. Their average size was about 7 µm. In the 140-week-old individuals an increase was observed in the number of oligodendrocytes with medium and dark cytoplasm, and their average size was about 6.79 µm. The perimeters of the three types of oligodendrocytes were similar in the two age groups – about 20 µm. There were also no statistically significant differences in the surface area of the three types of oligodendrocytes in the 25- and 140-week-old rats. The average surface area of these cells was about 40 µm2 . Oligodendrocytes have been neglected in research on older individuals and should therefore be analysed in this regard.
Oligodendrocytes (OLs) are myelinating cells of the central nervous system (CNS). They are a highly specialized type of glial cell in the CNS of vertebrates, which guarantee the transmission of action potentials over long distances by producing a myelin sheath that wraps adjacent axons. Although they are often credited merely with participation in myelination, recent research has led to a radical change in the understanding the role of these glial cells. OLs are currently understood to be plastic and adaptive cells, capable of responding quickly to changes taking place in the spatial neuronal network in the CNS. Due to their complex differentiation process and their physiology, OLs are among the most sensitive cells in the CNS. Finding answers about their interactions with other types of glial cells may result in benefits in the form of neuroprotection and axon plasticity. Damage to OLs and the myelin sheath is one of processes contributing to the development of crippling neurological diseases, although the role of these cells in neurodegeneration remains controversial. This article not only presents OLs as cells whose ultimate goal is to produce myelin sheaths, but also discusses their involvement in neurodegenerative diseases.
The aim of the study was the evaluation of changes in the adrenal cortex lysosomal enzymes activity during experimental alloxan-induced diabetes mellitus in rabbits. We checked the activity of acid phosphatase, β-D-galactosidase, N-acetyl-β-D-glucosaminidase (NAGL) and lipase. The study was performed on 124 rabbits divided into five groups: one control and four experimental. Diabetes mellitus was induced by a single injection of 10% alloxan solution into the auricular vein in a dose of 10 mg per kg body weight. Animals from experimental groups were killed in the 21st, 42nd, 90th and 180th days of the study. Adrenal glands were removed. Enzymes activity was assayed by spectrophotometric methods. Changes in free and bound fractions of examined lysosomal enzymes activity were noticed already in the 21st day of diabetes. The most escalated changes were observed in the 42nd day of the study. Performed statistical variance analysis demonstrated statistically highly significant differences for activity of both fractions of NAGL and lipase, as well as for free fraction activity of acid phosphatase and β-D-galactosidase. The obtained data confirmed the influence of diabetes mellitus on changes in the activity of examined lysosomal enzymes in the adrenal cortex.
The aim of the study was to analyze sexual activities of gilts representing various genotype groups in the RBP4 and MC4R locus. Observations of gilt behaviour during the first and the second oestrus (before initiation of the reproduction phase) were carried out in the Pulawska breed from conservation breeding. The evaluation process comprised the duration of the heat as well as the intensity of heat behaviours. Polymorphism identification in RBP4 (SNP: rs55618789) and MC4R (SNP: rs81219178) genes was performed, which resulted in the identification of three (MC4R: AA, AG and GG) and two (RBP4: CC and CT) gilt genotype groups. Significantly varying sexual activities were observed: the most intensive heat symptoms were demonstrated by CT gilts in the course of the first (P ≤ 0.05) and second (P ≤ 0.01) oestrus (locus RBP4) reaching, on average, 2.15 ± 0.13 and 2.52 ± 0.13 pt. It was further determined that the heats of CT gilts lasted longer and this difference, in the second heat, was significant (P ≤ 0.01). In the case of the MC4R locus, significant differences in gilt sexual activities were observed only in the course of the second oestrus (P ≤ 0.05). In addition, a strong association was also demonstrated of AA (locus MC4R) and CC (locus RBP4) genotypes with the thickness of the subcutaneous fat tissue (P ≤ 0.05) amounting in these gilts to 11.57 ± 0.21 mm and 11.50 ± 0.19 mm, respectively.
The aim of the study was to evaluate the influence of the diet enriched with linseed on morphometric, densitometric and mechanical properties of tibio-tarsus and tarso-metatarsus in 14-month-old ostriches. The experimental diet including 4% of linseed was applied to ostriches (N=8) starting from the attainment of 45 kg of body weight, while the control birds (N=8) were fed the standard diet. At the age of 14 months of life, blood samples were collected and the birds were slaughtered to isolate left tibio-tarsus and tarso-metatarsus. Dual-energy X-ray absorptiometry method was used to evaluate the bone mineral density and bone mineral content. Using quantitative computed tomography, total bone volume, mean volumetric bone mineral density, volumetric bone mineral density of trabecular and cortical bone, cortical bone area, calcium hydroxyapatite density of the trabecular and cortical bone were also determined.Cross-sectional area, second moment of inertia, mean relative wall thickness and cortical index were determined. Maximum elastic strength and ultimate strength of bones were determined using three-point bending test. Total antioxidative capacity in the serum was measured using commercial photometric test. In the experimental group of males, cortical bone area reached significantly higher value, while calcium hydroxyapatite density of the trabecular bone of tibio-tarsus was significantly lower, when compared to sex-matched controls (P<0.05). In conclusion, the experimental diet enriched with 4% of linseed, starting from 45 of kg of body weight of birds, had neither the positive nor negative effects on the evaluated bone properties in 14-month-old ostriches. Thus, higher dietary dosage of linseed or different administration period of the experimental diet should be applied to expect effects on skeletal system quality in growing ostriches.
The aim of the study was a quantitative and cytoarchitectonic examination of neurons of the ventral hippocampal CA1-CA4 fields in somatically mature female American mink (Neovison vison) (N = 6). Brains were removed and examined under a light microscope. The samples were stained by Nissl’s standard method, and histological samples were used for morphometric analysis. All ventral hippocampal CA1-CA4 fields were analyzed cytoarchitectonically and morphometrically with a calibrated image analysis system that consisted of a computer equipped with the Cell^D software Soft Imaging System (SIS) with an integrated digital camera Colorview IIIu (Soft Imaging System). Morphometric investigations of the pyramidal layer showed that the cells of the hippocampal CA1-CA4 fields in adult female American mink differ in size, shape, cell area, nucleus area and the nucleus-to-cell ratio (in%). The cells of the CA2 field were densely arranged, pyramidal and contained a small amount of cytoplasm; their size was differentiated. They were the largest in size (15.06 μm) and diameter (14.5 μm). The cells of the CA1 field had the smallest size (8.5 μm) and diameter (8.6 μm). In the CA3 field, small, densely packed neurons dominated, whereas neurons in the CA4 field formed a thin strand of loosely arranged cells. Given the increasing interest in hippocampal areas, it is necessary to continue studies of their morphology and morphometry in healthy animals and in those suffering from neurodegenerative diseases.
Investigated were morphological and densitometric parameters of the tihiotarsal bones in White Kołuda Geese over postatal period as influenced by sex, age and bone area using dual-energy Xray absorptiometry and peripheral quantitative computed tomography. The study was performed on 100 bones of geese obtained from both sexes on 1, 14, 28, 42 and 56 day of life. Body weight,bone weight, bone mineral density (BMD), bone mineral content (BMC), volumetric bone mineral density (vBMD), total bone mineral content (tBMC), cortical bone mineral density (CTR_DEN),cortical bone mineral content (CRT_CNT), trabecular bone mineral density (TRAB_DEN) and trabecular bone mineral content (TRAB_CNT) of tihiotarsal bone were determined.vBMD in the proximal metaphyses generally increased with age in both sexes and in females was higher than in males (especially in mid-diaphysis). Similar trends were observed for tBMC in middiaphysis of bones. The tBMC in proximal metaphyses reached maximum in females as early as on day 28, whereas in males 2 weeks later (on day 42). A significant decrease in TRAB_DEN and TRAB_CNT was also observed in males in both sections of the bone on day 42 and 56, whereas TRAB_DEN in the mid-diaphysis attenuated between day 28 and 42. Most deformities of tibial bones in males were observed in week 6 (42 day). In females, tibiotarsal deformations and fractures were found in week 6 and 8 of age, which was slightly later than the critical developmental stage in males.
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