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991.
We used explant cultures of adult mouse dorsal root ganglia with spinal nerve attached growing in Matrigel to assess the effects of the non-immunosuppressive immunophilin ligand GPI-1046 [Snyder et al. (1998) TIPS 19, 21-26] on the growth rate of regenerating sensory axons and found a potent stimulation of axon growth. In these explant cultures, naked, unfasciculated axons emerge from the cut end of the spinal nerve and continue to grow in the Matrigel for up to eight days [Tonge et al. (1996) Neuroscience 73, 541-551]. Some axons are entirely smooth whilst others show prominent varicosities. Some of the former express the phosphorylated neurofilament epitope recognised by monoclonal antibody RT97, a marker for large calibre, myelinated axons, whilst the latter express calcitonin gene-related peptide, predominantly a marker for unmyelinated, and small diameter myelinated sensory axons. Many of the axons in these cultures also express the low-affinity neurotrophin receptor p75. GPI-1046 has been shown to have striking stimulatory effects on embryonic primary sensory axons growing in vitro and it was therefore of interest to see whether it could also enhance regenerating sensory axon growth from the adult ganglia in our cultures. GPI-1046 potently stimulated axon growth in our cultures in a dose-dependent manner. The stimulatory effect was not dependent on the class of sensory axon. These observations show that GPI-1046 is a potent stimulator of regenerating axons from adult, primary sensory neurones. The cellular site of action of GPI-1046 is unknown. To distinguish between a direct effect of the drug on neurones and an indirect effect we compared the effects of GPI-1046 on explant and dissociated cultures. In confirmation of previous results, we found that GPI-1046 potently stimulated axon outgrowth from explants of embryonic chick dorsal root ganglia. However, the drug was without effect on dissociated embryonic dorsal root ganglion neurones, suggesting that non-neuronal cells are important for axon growth stimulation.  相似文献   
992.
BACKGROUND: Complex allergenic sources such as moulds, foods and mites contain complex panels of IgE-binding molecules which need to be cloned, produced and characterized in order to mimic the entire allergenicity of whole extracts reconstituted by mixing single standardized recombinant allergens. METHODS: Phage surface display of cDNA libraries selectively enriched for allergen-expressing clones using IgE from allergic patients allows rapid isolation of large panels of allergens. For the characterization of all different clones present in enriched cDNA libraries in a fast and cost-effective way, high-throughput screening technology is required. RESULTS: The combination of selective enrichment of cDNA libraries based on biopanning against serum IgE from sensitized patients and automated robot technology for picking and high-density gridding of clones onto filter membranes, followed by hybridization, enables fast identification of all the different clones present in an enriched library. The consequent application of selective enrichment and robotic-based screening allows, within weeks, cloning and characterization of the whole allergenic repertoire of any organisms. CONCLUSIONS: Robotic-based high-throughput screening of clones selected for IgE-binding capacity from phage surface-displayed cDNA libraries of Aspergillus fumigatus, Cladosporium herbarum, Coprinus comatus, Malassezia furfur, peanut and human lung tissue allowed rapid characterization of 81, 28, 37, 27, 8 and 151 different sequences, respectively. All these cDNAs bear a high probability to encode allergens derived from the respective allergenic source.  相似文献   
993.
The topography and structure of corpuscular mechanoreceptors in the shoulder joint capsule and periarticular connective tissue of a small laboratory marsupial (monodelphis domestica) were studied using light and electron microscopy. This animal is known to use its upper extremities for a wide range of activities like climbing and manipulating food. Thus, the shoulder joint of this animal species has a similar wide range of movement as the human shoulder joint, but is small enough for serial sectioning in its entirety. Silver stained serial paraffin sections were examined under the light microscope and the distribution of the different types of mechanoreceptors was reconstructed using three-dimensional image processing. In addition, selected mechanoreceptors were studied electron microscopically. Approximately 100 small lamellated corpuscles were found in the dense connective tissue of the joint capsule close to the insertion on the scapula and in the thickening of the joint capsule close to the glenoid labrum. Ruffini corpuscles were found in much smaller numbers in the moderately dense connective tissue of the axillary region. Only very few Vater-Pacinian corpuscles were seen in the soft periarticular connective tissue. The large number and localization of mechanoreceptor corpuscles in the shoulder joint capsule especially close to the glenoid labrum suggests, that these specialized nerve endings are likely to play an important role in control of joint movement. They can induce protective reflexes during extreme movements in the shoulder joint preventing shoulder luxation by increasing the tone of muscles pressing the humerus head into the glenoid cavity.  相似文献   
994.
Left Bochdalek hernia is a serious and complex condition with high mortality. In most cases, it presents in the neonatal period and is seldom found later in life when symptomatology, usually after an asymptomatic period, is quite different and the prognosis excellent. The embryological development of left Bochdalek hernia suggests the presence of abdominal content in the left pleural cavity before birth. The type of clinical presentation and the prognosis depend on the time of visceral herniation. This study presents two cases of left Bochdalek hernia with delayed presentation. In both cases, after surgical reposition of the hernia, a small congenital diaphragmatic defect was found hidden between the rims of diaphragm. This indicates the possibility for the abdominal content to enter the left pleural cavity at the time of presentation.  相似文献   
995.
Endothelial precursor cells (EPCs) cultured from adult bone marrow (BM) have been shown to mediate neovasculogenesis in murine models of vascular injury. We sought to directly compare umbilical cord blood (UCB)- and BM-derived EPC surface phenotypes and in vivo functional capacity. UCB and BM EPCs derived from mononuclear cells (MNC) were phenotyped by surface staining for expression of stromal (Stro-1, CXCR4, CD105, and CD73), endothelial (CD31, CD146, and vascular endothelial [VE]-cadherin), stem cell (CD34 and CD133), and monocyte (CD14) surface markers and analyzed by flow cytometry. The nonobese diabetic/severe combined immunodeficiency murine model of hind-limb ischemia was used to analyze the potential of MNCs and culture-derived EPCs from UCB and BM to mediate neovasculogenesis. Histologic evaluation of the in vivo studies included capillary density as a measure of neovascularization. Surface CXCR4 expression was notably higher on UCB-derived EPCs (64.29%+/-7.41%) compared with BM (19.69%+/-5.49%; P=.021). Although the 2 sources of EPCs were comparable in expression of endothelial and monocyte markers, BM-derived EPCs contained higher proportions of cells expressing stromal cell markers (CD105 and CD73). Injection of UCB- or BM-derived EPCs resulted in significantly improved perfusion as measured by laser Doppler imaging at days 7 and 14 after femoral artery ligation in nonobese diabetic/severe combined immunodeficiency mice compared with controls (P<.05). Injection of uncultured MNCs from BM or UCB showed no significant difference from control mice (P=.119; P=.177). Tissue samples harvested from the lower calf muscle at day 28 demonstrated increased capillary densities in mice receiving BM- or UCB-derived EPCs. In conclusion, we found that UCB and BM-derived EPCs differ in CXCR4 expression and stromal surface markers but mediate equivalent neovasculogenesis in vivo as measured by Doppler flow and histologic analyses.  相似文献   
996.
The effects of pretreatment with β-carotene-containing preparation carinat on the development of renal tumors in rats receiving single intravenous injection of chemical carcinogen 3-(1-α-L-arabinopyranosyl)-1-methyl-1-nitrosourea were studied. Fourteen months after carcinogen administration, the degree of lipid oxidation in rat kidneys 2.5-fold surpassed that in animals receiving carinat in a dose producingin vivo antioxidant effect. Carinat decreased the total number of induced tumors and the incidence of mesenchymal renal tumors and suppressed the development of multiple tumors. The accumulation of lipoperoxides in the kidneys during carcinogenesis is associated with activation of free radical processes and carcinogen-induced inhibition of lipoperoxide enzymatic degradation and probably promotes renal malignancies due to co-carcinogenic action of these compounds. The data suggest that carinat-induced suppression of tumor development attests to antioxidant effects of β-carotene. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 130, No. 7, pp. 95–97, July, 2000  相似文献   
997.
An affinity chromatography technique was utilized to isolate and purify the receptors of Escherichia coli K88ac(+) fimbriae from the mucus of the small intestines of newborn piglets. Purified K88ac+ fimbriae were covalently immobilized onto a beaded agarose matrix (Sepharose 4B). The immobilized fimbriae were used for the affinity purification of the K88ac+ receptors. Only two major proteins were tightly and specifically bound to the immobilized fimbriae after the column containing bound receptor was washed exhaustively with a buffer containing a high concentration of salt and a detergent. The receptors were eluted as a single component at a low pH. The isolated proteins were then subjected to enzyme-linked immunosorbent assay, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and Western blot (immunoblot) analyses. The two proteins were of high purity, were responsible for nearly all of the fimbrial binding capacity of the crude mucus, and had molecular masses of 26 and 41 kDa. The method for isolation of E. coli binding proteins is simple and yields purified intestinal receptors in a single chromatographic run. The intestinal mucus of different piglets has different proportions of the two receptor proteins.  相似文献   
998.
The objective of this study was to quantify, in vivo, constitutive and tumor necrosis factor alpha (TNF-alpha)-enhanced expression of mucosal addressin cell adhesion molecule-1 (MAdCAM-1) in different tissues from healthy wild-type mice (C57BL/6) as well as interleukin-10 (IL-10)-deficient mice with and without active colitis. Using the dual radiolabel monoclonal antibody technique, we found substantial constitutive expression of MAdCAM-1 in the intestine, colon, and mesenteric lymph nodes. MAdCAM-1 expression in these tissues was significantly enhanced, in a time-dependent manner, by systemic administration of TNF-alpha. Maximum surface expression was observed at 18 h after TNF-alpha administration and remained significantly elevated at 48 h post-TNF-alpha injection. No significant constitutive nor TNF-alpha-induced expression of MAdCAM-1 was detected in skeletal muscle, brain, or heart. In IL-10-deficient (IL-10 k/o) mice with no clinical or histological evidence of colitis, constitutive and TNF-alpha-induced expression of MAdCAM-1 in the intestine, cecum, and colon was not different from those values obtained with healthy wild-type controls. IL-10-deficient mice with active colitis exhibited a four- to fivefold greater expression of MAdCAM-1 in the cecum and colon compared with their healthy controls or to IL-10 k/o mice with no evidence of colitis. Taken together, these data demonstrate that TNF-alpha enhances surface expression of MAdCAM-1 in intestinal and colonic tissues to the same extent in both wild-type and IL-10 k/o mice with no colonic inflammation, whereas IL-10 k/o mice with active colitis exhibited a profound up-regulation of MAdCAM-1 in the colon.  相似文献   
999.
1000.
The birth of 12 healthy infants to fathers with non-mosaic Klinefelter's syndrome has been reported so far. The spermatozoa for these pregnancies was obtained from frozen-thawed ejaculate in one pregnancy (twins) and from the testis in the remaining 10 infants. All of them had a normal karyotype. We describe a patient with non-mosaic Klinefelter's syndrome from whom a testicular biopsy was obtained and motile spermatozoa were collected. Of 16 oocytes that were injected, 14 fertilized and cleaved. Three embryos were transferred, resulting in a triplet pregnancy. Karyotype analysis from chorionic villous sampling revealed 46,XX, 46,XY and 46,XXY from the three fetuses. The affected 46,XXY fetus was reduced on the 14th gestational week. The pregnancy culminated with the birth of a healthy male and female, on the 36th gestational week, weighing 3600 and 2660 g respectively. This case report proves the presence of hyperploid spermatozoa in the seminiferous lumen, and strengthens the necessity of genetic diagnosis of the embryos or fetuses in such pregnancies to fathers with non-mosaic Klinefelter's syndrome.  相似文献   
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