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The projections of the olfactory bulb, the primordial dorsal, piriform and hippocampal pallia, and of the dorsal thalamus were studied in the lamprey Lampetra fluviatilis using horseradish peroxidase (HRP) and HRP coupled to the wheat germ agglutinin (WGA-HRP). There was obtained an experimental morphological evidence of the presence of the direct thalamo-telencephalic projections in this vertebrate species. The anterior and posterior parts of the dorsal thalamic nucleus, the nucleus of Bellonci, the primordial geniculate bodies, the rostral part of the midbrain were identified as the sources of the telencephalic afferents. These connections may serve as a morphological substrate for transmission of nonolfactory impulses to the telencephalon of the lamprey. The projections of the nucleus of Bellonci into the primordial hippocamp were compared to the limbic thalamo-hippocampal pathways of other vertebrates. We have established, that the fibers ascending from the dorsal thalamus were distributed in the same areas, as those descending from the olfactory bulb. These are: mainly the primordial hippocamp and only a few fibers reach the dorsal and piriform pallia, as well as an area free of olfactory projections--the dorsal part of the subhippocampal lobe. We have also demonstrated that, the secondary olfactory fibers mainly projected ipsilaterally to the primordial dorsal and piriform pallia. A lesser dense bulbar projection has been observed ipsilaterally in the primordial hippocamp and in the ventral part of the subhippocampal lobe. Only few olfactory projections were found in the pallial areas and in the subhippocampal lobe contralaterally. The olfactory fiber terminals were also observed ipsilaterally in the septum, striatum, preoptic area and in the contralateral olfactory bulb. Bilateral bulbofugal projections also occur in the diencephalon, namely in the ventral thalamus and in the hypothalamus. Caudally, the secondary olfactory fibers can be traced up to the area of the posterior tuberculum. Afferents to the olfactory bulb in the river lamprey originate in the subhippocampal lobe, in all three pallial formations and probably in the dorsal thalamus. These structures are at the same time the target zones for the olfactory bulb efferent projections, thus being connected reciprocally with the olfactory bulb. 相似文献
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AJ Jiménez JM Mancera MA Pombal JM Pérez-Fígares P Fernández-Llebrez 《Canadian Metallurgical Quarterly》1996,368(2):185-197
The formation of microvascular sprouts during angiogenesis requires that endothelial cells move through an extracellular matrix. Endothelial cells that migrate in vitro generate forces of traction that compress (i.e., contract) and reorganize vicinial extracellular matrix, a process that might be important for angiogenic invasion and morphogenesis in vivo. To study potential relationships between traction and angiogenesis, we have measured the contraction of fibrillar type I collagen gels by endothelial cells in vitro. We found that the capacity of bovine aortic endothelial (BAE) cells to remodel type I collagen was similar to that of human dermal fibroblasts--a cell type that generates high levels of traction. Contraction of collagen by BAE cells was stimulated by fetal bovine serum, human plasma-derived serum, bovine serum albumin, and the angiogenic factors phorbol myristate acetate and basic fibroblast growth factor (bFGF). In contrast, fibronectin and immunoglobulin from bovine serum, several nonserum proteins, and polyvinyl pyrrolidone (a nonproteinaceous substitute for albumin in artificial plasma) were not stimulatory. Contraction of collagen by BAE cells was diminished by an inhibitor of metalloproteinases (1,10-phenanthroline) at concentrations that were not obviously cytotoxic. Zymography of proteins secreted by BAE cells that had contracted collagen gels revealed matrix metalloproteinase 2. Subconfluent BAE cells that were migratory and proliferating were more effective contractors of collagen than were quiescent, confluent cells of the same strain. Moreover, bovine capillary endothelial cells contracted collagen gels to a greater degree than was seen with BAE cells. Collectively, our observations indicate that traction-driven reorganization of fibrillar type I collagen by endothelial cells is sensitive to different mediators, some of which, e.g., bFGF, are known regulators of angiogenesis in vivo. 相似文献
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Isolated nephrons from premetamorphic lamprey larvae and adult animals were obtained using microdissection and kidney collagenase treatment methods. Significant differences in the architectonics of kidney tubules were found in larvae as compared with adults. The position of larval kidney was cranial while that in adult lampreys was caudal. The absence of nephron loop was noted in larval kidney. Distal and proximal tubules were shifted one from another in mediolateral direction. Distal tubule was significantly larger than proximal one. Mesonephric duct was located laterally near the glomus. Kidney tubules morphogenesis and nephron population number increase was observed at premetamorphic stage of larval kidney development. 相似文献
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AD Pickering 《Canadian Metallurgical Quarterly》1976,30(3):340-346
Of 325 patients with retinal detachments, 110 patients (34%) had aphakic eyes. These detachments were subdivided into three types based on their clinical appearance during indirect ophthalmoscopy and slit-lamp biomicroscopy. Fifty-two patients (47%) had aphakic detachments (Type 3), categorized by small tears due to traction along a prominent posterior or vitreous base and the absence of visible retinal degeneration. Fifty of the 52 patients in this group were operated on by using a modification of the nondrainage procedure developed by Custodis, and employing cryosurgical coagulation and an external encircling buckle using a 3-mm silicone sponge. The sponge was secured beneath the retinal tear, and its length was shortened to produce a moderately elevated buckle. Although 50% of retinal tears were open at the end of the operation, 60% of all eyes operated on without drainage reattached in 16 hours, 90% in one week, and the remainder in two weeks. Visual acuity of 70% of these patients was 6/15 (20/50) or better when tested six months after surgery. The operation did not wall away peripheral fluid, but closed retinal tears completely, reduced circumferential vitreous traction, and avoided drainage of subretinal fluid. 相似文献
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In order to assess the contribution of oxidative metabolism to K+(86Rb+) transport across the lamprey red cell membrane, the effects of various metabolic inhibitors were examined. The influx of K+ was reduced markedly in the presence of 20 mumol/l 2,4-dinitrophenol (2,4-DNP) or rotenone, and to a lesser extent by 1 mmol/l cyanide. Rotenone produced complete inhibition of the K+ active transport and a partial blockade of K+ channels by 28% on the average. Addition of 2,4-DNP to incubation media resulted in a significant reduction of both active transport of K+ (by 47%) and of K+ movement via channels (by 57%). The inhibitory effect of 2,4-DNP on total K+ influx was independent on decreasing extracellular pHe from 7.4 to 6.5. The blocking action of 1 mmol/l Ba2+ on K+ channels was abolished in the red cells incubated at pHe 6.5. Treatment of the red cells with 1 mmol/l cyanide diminished active transport of K+ to about 34% of control values but did not affect K+ channels. The obtained data indicate that in the lamprey red blood cells at least a half of energy needed for the active transport of K+ is supplied with ATP produced by oxidative phosphorylation. It may be suggested that NADH dehydrogenase is the key enzyme required for active transport of K+ in the cells, as rotenone, a selective blocker of this enzyme, causes a complete blockade of the Na+, K(+)-pump. 相似文献
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B Anton J Fein T To X Li L Silberstein CJ Evans 《Canadian Metallurgical Quarterly》1996,368(2):229-251
A novel member of the opioid receptor family (ORL-1) has been cloned from a variety of vertebrates. ORL-1 does not bind any of the classical opioids, although a high affinity endogenous agonist with close homology to dynorphin has recently been identified. We have generated a monoclonal antibody to the N-terminus of ORL-1 to map areas of receptor expression in rat central nervous system (CNS). Intense and specific immunolabeling was observed in multiple areas in the diencephalon, mesencephalon, pons/medulla, and spinal cord. In the telencephalon, intense labeling was observed in the neuropil throughout layers II-V in the neocortex, the anterior olfactory nuclear complex, the pyriform cortex, the CA1-CA4 fields and dentate gyrus of the hippocampus, and in many of the septal and basal forebrain areas. In contrast to other members of the opioid receptor family, light labeling for ORL-1 was observed in telencephalic areas such as caudate-putamen. In the cerebellum, ORL-1 immunoreactivity was only observed in the deep nuclei. Throughout the CNS the majority of labelling was localized to fiber processes and fine puncta, although labeled scattered perikarya were observed in a few brain areas such as the hilus dentate in the hippocampus and some nuclei in the brainstem and spinal cord. The present mapping study is consistent with the reported distribution of ORL-1 mRNA and provides the first immunohistochemical report on anatomical and cellular distribution of ORL-1 receptor in the rat CNS. 相似文献
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The antiseptic activity of Listerine and Cool Mint Listerine against methicillin-resistant Staphylococcus aureus (MRSA), Candida albicans, human immuno deficiency virus (HIV) and oral bacteria was examined in this study. Exposure for 30 seconds to Listerine killed MRSA completely. Exposure for 30 seconds significantly decreased viable cells of C. albicans. More than 60% of HIV was inactivated by a 30 second exposure to 50% Listerine. Listerine exhibited a potent bactericidal effect against cariogenic and periodontopathic bacteria. Cool Mint Listerine had almost the same antiseptic effect against tested microorganisms. Listerine appears to be effective for killing etiologic microorganisms of opportunistic infection in the oral cavity. 相似文献
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G Pahud N Salem J van de Goor J Medilanski N Pellegrinelli L Eder-Colli 《Canadian Metallurgical Quarterly》1998,10(5):1644-1653
Choline acetyltransferase (ChAT), the enzyme which catalyses the biosynthesis of the neurotransmitter acetylcholine, exists in a soluble and membrane-bound form in cholinergic nerve terminals of different animal species. This study was performed on the enzyme present in Drosophila central nervous system. We show that the two forms of the enzyme have the same apparent molecular weight (75 kDa) when analysed by immunoblotting using an antibody we raised against the recombinant enzyme. According to different authors, membrane-bound enzyme might be associated with synaptic vesicles or plasma membrane. Subfractionation of Drosophila head homogenates in linear glycerol gradients showed that ChAT does not associate with synaptic vesicles. Analysis of ChAT activity and immunoreactivity showed that two peaks of ChAT were produced. One peak was present in fractions containing soluble components and the other was associated with rapidly sedimenting membranes containing plasma membranes. ChAT in the first peak was mainly hydrophilic. A large proportion of ChAT associated with rapidly sedimenting membranes was amphiphilic. Further fractionation of these membranes by flotation in sucrose gradients showed that membrane-associated ChAT sedimented in fractions containing plasma membrane marker. Membrane-bound ChAT was neither solubilized nor converted to hydrophilic enzyme after membrane treatment with 1 M hydroxylamine, suggesting that the enzyme is not palmitoylated and therefore not anchored to membrane through thioester-linked long chain fatty acid. Partial solubilization of ChAT present on membranes with urea and carbonate suggests that this form of ChAT is a peripheral membrane protein. Carbonate solubilization of membrane-bound ChAT converted the enzyme from hydrophobic to hydrophilic protein. 相似文献
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PS Bolton 《Canadian Metallurgical Quarterly》1998,21(8):553-563
BACKGROUND: There is some evidence to suggest that dysfunction in the sensory system of the neck may result in a gamut of signs and symptoms. However, a sound understanding of the somatosensory system in the neck and its normal influence on the central nervous system is essential before signs and symptoms can be identified as representations of ill health or disease arising from the neck. OBJECTIVE: To briefly review current knowledge of the somatosensory system of the neck and to consider its connections and influence on the central nervous system. DATA SOURCES: Information was obtained from peer-reviewed scientific journals and proceedings of scientific meetings that have investigated or considered anatomical and physiological aspects of the sensory system in the necks of human and nonhuman vertebrates. CONCLUSION: Studies involving human and nonhuman vertebrates have provided considerable information about the anatomy of the sensory receptors located in the neck and about where information from these receptors is relayed in the spinal cord and brain. Physiological experiments involving electrical and natural stimulation of the head and neck regions have identified a role for some of these receptors in neck-evoked reflexes. It is clear that in addition to signaling nociception, the somatosensory system of the neck may influence the motor control of the neck, eyes, limbs, respiratory muscles and possibly the activity of some preganglionic sympathetic nerves. 相似文献
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This review of the literature on aging and the central nervous system attempts to cover the basic perameters investigated at both human and infrahuman levels for the better part of the last century. The results have indicated that there is a rather considerable lack of consistency in the data both within the frame of reference of a single species, and with regard to intraspecies comparisons. We have suggested that possible reasons for the contradictory findings would rest upon variability in techniques employed but, perhaps more importantly, on the failure of investigators in this area to standardize terminology. It is suggested that such a standardization might well be one of the more useful things to be accomplished in order to facilitate the interpretation of future work. The literature review first dealt with gross, i.e., macroscopic changes in brain morphology that could correlate with age, and then covered changes at the microscopic level. Finally, a brief review of the literature with regard to the biochemistry of aging was carried out. Implications of the data were noted where appropriate. 相似文献
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Prostaglandins (PGs) were first described in the brain by Samuelsson over 30 years ago (Samuelsson, 1964). Since then a large number of studies have shown that PGs are formed in regions of the brain and spinal cord in response to a variety of stimuli. The recent identification of two forms of cyclooxygenase (COX; Kujubu et al., 1991; Xie et al., 1991; Smith and DeWitt, 1996), both of which are expressed in the brain, along with superior tools for mapping COX distribution, has spurred a resurgence of interest in the role of PGs in the central nervous system (CNS). In this review we will describe new data in this area, focusing on the distribution and potential role of the COX isoforms in brain function and disease. 相似文献
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A Compston 《Canadian Metallurgical Quarterly》1996,1(6):388-392
The three typical stages in the clinical course of multiple sclerosis (relapse, persistent disability and progression) can be explained on the basis of inflammation, demyelination and failure of repair leading to axon degeneration and astrocytosis. Strategies are being evaluated for limiting the inflammatory process using immunological treatments and these may have unexpected dividends in promoting endogenous remyelination. Increasing knowledge on glial lineages and axon-glial interactions needed for stable myelination also offer the prospect for enhancing remyelination through growth factor therapy and cell implantation. 相似文献
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MR Paradis 《Canadian Metallurgical Quarterly》1998,14(3):543-61, vii
Neoplasia of the central nervous system (CNS) can be divided into two main categories: nonpituitary CNS neoplasia and pituitary adenomas. Nonpituitary CNS neoplasias are generally compressive in nature, although some are also invasive. The majority of reported CNS tumors are secondary with only a few originating from nervous tissue. Pituitary adenomas predominantly occur in the pars intermedia of the older horse. Clinical signs, diagnostic testing, and possible treatments are discussed. 相似文献
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N Chartrel JM Conlon F Collin B Braun D Waugh M Vallarino SL Lahrichi JE Rivier H Vaudry 《Canadian Metallurgical Quarterly》1996,364(2):324-339
Urotensin II (UII) is traditionally regarded as a product of the neurosecretory cells in the caudal portion of the spinal cord of jawed fishes. A peptide related to UII has been recently isolated from the frog brain, thereby providing the first evidence that UII is also present in the central nervous system of a tetrapod. In the present study, we have investigated the distribution of UII-immunoreactive elements in the brain and spinal cord of the frog Rana ridibunda by immunofluorescence using an antiserum directed against the conserved cyclic region of the peptide. Two distinct populations of UII-immunoreactive perikarya were visualized. The first group of positive neurons was found in the nucleus hypoglossus of the medulla oblongata, which controls two striated muscles of the tongue. The second population of immunoreactive cell bodies was represented by a subset of motoneurons that were particularly abundant in the caudal region of the cord (34% of the motoneuron population). The telencephalon, diencephalon, mesencephalon, and metencephalon were totally devoid of UII-containing cell bodies but displayed dense networks of UII-immunoreactive fibers, notably in the thalamus, the tectum, the tegmentum, and the granular layer of the cerebellum. In addition, a dense bundle of long varicose processes projecting rostrocaudally was observed coursing along the ventral surface of the brain from the midtelencephalon to the medulla oblongata. Reversed-phase high-performance liquid chromatography analysis of frog brain, medulla oblongata, and spinal cord extracts revealed that, in all three regions, UII-immunoreactive material eluted as a single peak which exhibited the same retention time as synthetic frog UII. Taken together, these data indicate that UII, in addition to its neuroendocrine functions in fish, is a potential regulatory peptide in the central nervous system of amphibians. 相似文献
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A Kolonko 《Canadian Metallurgical Quarterly》1995,49(6):719-731
A lot of clinical processes following excessive stimulation of glutamate receptors seem to participate in pathophysiology of numerous acute and chronic neurological disorders. The whole of these reactions has been named as "glutamate cascade", because of the central role of glutamate in initiation and intensification of these processes. In this article, classification of different types of glutamate receptors and several hypotheses concerning mechanisms of glutamate neurotoxic activity are presented. A wide variety of neurological diseases, which etiologies are more or less connected with glutamate toxicity are discussed. At last, the future perspectives for treatment by drugs which action is thought to be mediated through glutamate receptors are presented. 相似文献