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The hippocampus is important in learning and memory functions but its ability to aid in these functions declines during aging. In this study, we examined hippocampal proteins whose expressions changed in the aging process. A comparison of synaptosome proteins of hippocampus prepared from young-adult (9-week-old) rats with those from aged (30-month-old) rats by two-dimensional fluorescence difference gel electrophoresis revealed 24 spots that were expressed differently among about 1000 spots detected in both young-adult and aged rat samples. Nineteen of these 24 spots were identified by peptide mass fingerprinting. These proteins included chaperone proteins and proteins related to the cytoskeleton, neurotransmission, signal transduction and energy supply. The cytoskeleton-related proteins included actin and T-complex 1, which is thought to play a role in actin folding. Actin was up-regulated but T-complex 1 was down-regulated in aged rat synapses. These results suggest that age-dependent changes of actin filament formation are related to neuronal dysfunction associated with aging.  相似文献   
3.
Summary The extracellular matrix around nerve cell bodies in canine lateral and medial superior olivary nuclei was examined by conventional electron microscopy, Golgi impregnation and histochemical techniques. Each neuron is surrounded by a region of myelin-free neuropil embedded amongst the myelinated fibres of the trapezoid body. In the myelin-free neuropil there are astrocytes, axons, synaptic boutons and extracellular matrix. The extracellular matrix fills the spaces between slender axons near the terminals, synaptic boutons and glial processes, but not the synaptic cleft. Golgi impregnation selectively stains the perineuronal nets which cover some or all of the nerve cell bodies and dendrites. The Golgi-EM method revealed that the impregnated profiles of the nets are restricted to the extracellular matrix. Synaptic boutons are situated in the holes of the perineuronal nets. Peanut (PNA) and soybean (SBA) agglutinins bound the extracellular matrix but not the synaptic boutons, glial processes, nerve cell bodies or basal lamina of blood capillaries. Light microscopic immunohistochemistry of the glial fibrillary acidic protein (GFAP) and S-100 protein did not stain a layer corresponding to the extracellular matrix and synapses but showed an intensely positive reaction immediately outside this layer. These data suggest the existence of a unique microenvironment associated with glycoconjugates around nerve cell bodies in canine superior olivary nuclei.  相似文献   
4.
The specific cellular immune response to the partially purified pancreatic antigen was studied by the peripheral blood lymphocyte proliferation assay in patients with chronic pancreatitis, Sjögren's syndrome, and primary biliary cirrhosis. A significant positive result (stimulation index >2.0) was observed in 7 of 21 patients with idiopathic chronic pancreatitis (33%;P<0.05), 6 of 7 patients with Sjögren's syndrome-associated chronic pancreatitis (86%;P<0.0005), and 6 of 11 patients with Sjögren's syndrome (55%;P<0.01), compared to normal controls whose stimulation index was 0.94±0.28 (mean ± SD;n=14; range, 0.56–1.60). On the other hand, patients with alcoholic chronic pancreatitis (17%;n=12), stone-related chronic pancreatitis (0%;n=7), primary biliary cirrhosis-associated chronic pancreatitis (33%;n=3), primary biliary cirrhosis (0%;n=4), systemic lupus erythematosus (17%;n=6), and autoimmune thyroiditis (0%;n=6) showed no significant difference from normal controls. Furthermore, in patients with idiopathic chronic pancreatitis who had positive results, a lymphocyte proliferative response to the pancreatic antigen was observed in T cells, especially in the CD4+ T cell subpopulation. These results suggest that the pancreatic antigen plays a role in the pathogenesis of a part of idiopathic chronic pancreatitis and Sjögren's syndrome in association with T cell responses and, also, suggest that autoimmunity may be a possible etiological factor in chronic pancreatitis.  相似文献   
5.
The immuno-histochemical and drug-binding properties of intracisternal microtubules (IMs) in the RER of canine neurons were studied with antitubulin IgG and vinblastine. Specific fluorescence against antitubulin IgG was not detected in the RER in which the IMs were aggregated but was observed in the cytoplasm outside the RER. Injection of vinblastine into the sympathetic ganglion did not change the size, shape or arrangement of IMs in the RER, although typical honeycomb crystals were formed near IM-containing RER. These findings show that the IM does not possess antigenicity to antitubulin IgG and has no vinblastine-binding site. Thus it is suggested that the IM may be a defective or modified microtubule.  相似文献   
6.
The distribution of the calbindin D28k in the laryngeal sensory structures was studied by immunohistochemistry, immunoelectronmicroscopy, and double immunofluorescence with calretinin-immunoreactivity. Moreover, origin of the nerve endings were observed using retrograde tracer, fast blue. Immunoreactivity for calbindin D28k was found in the various types of nerve endings in the larynx, namely, laminar nerve endings, nerve endings associated with the taste buds, intraepithelial nerve endings, and endocrine cells. The laminar endings with calbindin D28k-immunoreactivity were observed in the subepithelial connective tissue. In some endings, terminals were expanded. The laminar endings were also observed in the perichondrium of the epiglottic cartilage. In the epiglottic and arytenoid epithelia, thick nerve fibers with calbindin D28k-immunoreactivity ascending to taste buds and intragemmal nerve fibers were also observed. Within the epithelial layer, intraepithelial free nerve endings with calbindin D28k-immunoreactivity were observed. Furthermore, diffuse endocrine cells were observed within the laryngeal epithelium. By immunoelectron microscopy, immunoreaction products in the endings mentioned above were localized in the cytoplasm of the axon terminals and nerve fibers which contained with numerous mitochondria. Out of the 100 laminar endings, 18 endings were immunopositive for both calbindin D28k and calretinin, 33 were positive for calbindin D28k but negative for calretinin, and 49 were positive for only calretinin in the double immunofluorescence microscopy. The nerve fibers associated with the taste buds and the free nerve endings, which immunostained for calbindin D28k, were not stained with antibody against calretinin. After injection of the fast blue in the laryngeal mucosa, fast blue-labeled cells were mainly observed in the nodose ganglia. Of the total number of labeled cell in the nodose and dorsal root ganglia at the level C1 to Th2, 65.1% occurred in nodose ganglia (572/879, n = 6). In the nodose ganglia, 79.7% of labeled cells (456/572) were immunoreacted for calbindin D28k. The distribution of calbindin D28k-immunoreactivity may be differnt from that of calretinin. It is suggested that calbindin D28k have regulatory role on intracellular calcium concentration in the laryngeal sensory corpuscles.  相似文献   
7.
Lectin histochemistry was used to identify sugar residues of IM-containing RER in elderly canine sympathetic ganglionic neurones. IM-inclusions stained with ConA-peroxidase conjugate, but not with soybean agglutinin (SBA), wheat germ agglutinin (WGA), peanut agglutinin (PNA), Dolichos biflorus agglutinin (DBA), Ricinus communis agglutinin (RCA I) and Ulex europaeus agglutinin (UEA I). ConA-binding sites were visualized within cisternae of RER containing IM; reaction product was localized in IM-containing RER cisternae and IM. Inhibition with specific sugars (0.1 M alpha-methyl-D-mannoside or 0.5 M D-glucose) blocked the binding of ConA to IM-inclusions and normal Nissl substance. When a low sugar concentration (5 x 10(-3) M alpha-methyl-D-mannoside or 0.2 M D-glucose) was employed, IM-inclusions were still strongly ConA-positive, but normal Nissl substance was not. These results demonstrate that IM-containing RER have an excessive amount of carbohydrates (mannose or glucose-rich sugars) which are essentially detected in flattened RER under normal conditions and further indicate that glycoproteins in IM differ from those in cytoplasmic microtubules.  相似文献   
8.
Aim: As techniques in laparoscopic cholecystectomy (LC) have improved, the role of routine prophylactic abdominal drainage may be limited. A retrospective review was carried out of patients undergoing elective LC to evaluate the benefit of routine drainage in simple uncomplicated procedures. Methods: This study of 295 patients with cholecystolithiasis or gallbladder polyp included 145 patients who underwent LC with drainage and 150 patients who underwent LC without drainage between 2003 and 2007. Allocation to drain or not to drain was non‐randomized and based on surgeon preference according to intraoperative findings. Patient characteristics, operative results, and postoperative outcomes were compared between the two groups with univariate analysis. Results: Time to first flatus and length of postoperative hospital stay in the LC without drainage group were shorter than in the LC with drainage group. There was no significant difference between the two groups with respect to postoperative complication rate. No complications were noted due to the lack of drain placement. Conclusion: The use of drain after simple elective uncomplicated LC could safely be limited to appropriate patients as judged by the operating surgeon.  相似文献   
9.
Dissection of the sinus of Valsalva is an extremely rare accident during percutaneous coronary intervention (PCI), but it can lead to serious complications such as dissection of the ascending aorta. We experienced a localized dissection of the right coronary cusp without coronary artery involvement that was induced by a guiding catheter during PCI in a patient with acute myocardial infarction. The localized dissection showed pooling of the contrast medium in the acute phase, but it subsided spontaneously after 12 days without any sequelae. Manipulation of the guiding catheter should be performed with great caution not only in the coronary artery but also in the sinus of Valsalva.  相似文献   
10.
We endoscopically measured pressures of the pancreatic duct (PP) and the sphincter of Oddi (SO) in patients with alcoholic (ALCP, n = 10), gallstone-associated (GSCP, n = 7), and idiopathic chronic pancreatitis (ICP, n = 21), and in 20 controls. The PP was significantly higher in the patients with ALCP (55.7 +/- 28.9 mm Hg), GSCP (33.6 +/- 16.2 mm Hg), or ICP (44.5 +/- 25.8 mm Hg) than in the controls (16.2 +/- 8.7 mm Hg), but there was no significant difference between ALCP, GSCP, and ICP. There was no significant difference between control subjects and ICP in the motility of SO. In ICP, there was no correlation between the PP and the motility of SO. In ALCP and GSCP, the frequencies of the papillary sphincter waves were significantly higher than in normal subjects, and there were correlations between the PP and the motility of SO. These data suggest that increased pancreatic ductal pressure in GSCP with papillitis or ALCP may be due in part to papillary dysfunction, but not in ICP.  相似文献   
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