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991.
992.
A neo-esophagus reconstructed by cultured human esophageal epithelial cells, smooth muscle cells, fibroblasts, and collagen 总被引:8,自引:0,他引:8
Hayashi K Ando N Ozawa S Kitagawa Y Miki H Sato M Kitajima M 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2004,50(3):261-266
The scientists involved in this study attempted to develop an artificial esophagus constructed of autologous cells grown by cell culture methods on an extracellular matrix. An artificial esophagus consisting of human esophageal epithelial cells, dermal fibroblasts, and smooth muscle cells isolated from the aortic media, was attempted. The purpose of this study was to examine whether smooth muscle cells could be used in the transforming matrix. Human fibroblasts were embedded in Type I collagen superimposed on the collagen layer of smooth muscle cells. Next, human esophageal epithelial cells were cultured on the collagen layer of the fibroblasts. The resulting collagen sheets were cultured in vitro for 1 week, then transplanted on the latissimus dorsi muscles of athymic rats. The sheets were examined histologically at 1 and 2 weeks using hematoxylin eosin and immunologic stain methods (antiactin antibody). At the end of 2 weeks after transplantation, on microscopic observation of the collagen sheets, it appeared that the epithelial layer, the submucosal tissue layer, and the proper muscle layer had been reconstructed. Additionally, the authors successfully isolated smooth muscle cells from the media of the left gastric artery as a surgical specimen by explant cell culture. The ability to transform collagen sheets consisting of esophageal epithelial cells, fibroblasts, and smooth muscle cells from a surgical specimen into a luminal structure may enable clinical application of the artificial esophagus. 相似文献
993.
Loop-mediated isothermal amplification method targeting the lytA gene for detection of Streptococcus pneumoniae 总被引:13,自引:0,他引:13
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Seki M Yamashita Y Torigoe H Tsuda H Sato S Maeno M 《Journal of clinical microbiology》2005,43(4):1581-1586
It is difficult to separate Streptococcus pneumoniae from the genotypically similar species Streptococcus mitis and Streptococcus oralis, which are commensals of the human oral cavity. A novel nucleic acid amplification technique, loop-mediated isothermal amplification (LAMP), which amplifies DNA under isothermal conditions (63 degrees C) with high specificity, efficiency, and rapidity, was examined regarding its applicability for detecting S. pneumoniae. An S. pneumoniae-specific LAMP primer targeting the lytA gene was designed. The primer specificity was validated using 10 Streptococcus and 7 non-Streptococcus species. Within 60 min, the assay could detect 10 or more copies of purified S. pneumoniae DNA with a sensitivity 1,000 times that of conventional PCR. Clinical isolates of 21 other strains (3 S. oralis, 17 S. mitis, and 1 Streptococcus species) that harbor virulence-factor-encoding genes (lytA or ply) were tried to differentiate S. pneumoniae. The detection of S. pneumoniae in clinical isolates was more selective using the LAMP method than using conventional PCR. Therefore, LAMP appears to be a sensitive and reliable means of diagnosing S. pneumoniae infection. 相似文献
994.
Aratanechemuge Y Komiya T Moteki H Katsuzaki H Imai K Hibasami H 《International journal of molecular medicine》2002,9(5):481-484
We have investigated the effects of ar-turmerone isolated from turmeric (Curcuma longa L) on DNA of human leukemia cell lines, Molt 4B, HL-60 and stomach cancer KATO III cells. It was found that selective induction of apoptosis by ar-turmerone was observed in human leukemia Molt 4B and HL-60 cells, but not in human stomach cancer KATO III cells. Morphological changes showing apoptotic bodies were observed in the human HL-60 and Molt 4B cells treated with ar-turmerone. The fragmentation of DNA by ar-turmerone to oligonucleosomal-sized fragments that is a characteristic of apoptosis was observed to be concentration- and time-dependent in Molt 4B and HL-60 cells, but not in KATO III cells. The data of the present study show that the suppression by ar-turmerone of growth of these leukemia cell lines results from the induction of apoptosis by this compound. 相似文献
995.
J. A. Vega M. E. Del Valle J. J. Haro B. Calzada S. Suarez-Garnacho L. Malinovsky 《Anatomical record (Hoboken, N.J. : 2007)》1993,236(4):730-736
The presence of nerve growth factor receptors (NGFr) in sensory nerve corpuscles of human digital skin, primarily Meissner and Pacinian corpuscles, was investigated immunohistochemically using two monoclonal antibodies directed against human-NGFr. To ensure the localization of NGFr immunoreactivity (IR) alternative sections to that processed for NGFr detection were assayed for neurofilament protein (NFP) and S-100 protein which selectively label the axon and the periaxonic specialized cells (lamellar cells of Meissner's corpuscles; inner-core cells of Pacinian corpuscles), respectively. Occurrence of NGFr IR was observed in both types of sensory corpuscles. In Meissner's corpuscles NGFr-IR was found in the lamellar cells, whereas in the Pacinian corpuscles the lamellae of the inner core, outer core, and capsule displayed NGFr IR. Moreover, a positive IR was observed in the central axon of some Pacinian corpuscles. However, remarkable differences were encountered among Pacinian corpuscles in the pattern of NGFr IR distribution. Present results demonstrate puscles in the pattern of NGFr IR distribution. Present results demonstrate the presence of NGFr IR in sensory nerve corpuscles of the human digital skin, suggesting that NGFr could be involved in the concentration of NGF and in the conveying of this molecule from the cutaneous sources to the cell body of NGF-dependent primary sensory neurons. However, the mechanisms involved in this process remain to be clarified. © 1993 Wiley-Liss, Inc. 相似文献
996.
Takahashi M Kanuka H Fujiwara H Koyama A Hasegawa M Miura M Iwatsubo T 《Neuroscience letters》2003,336(3):155-158
alpha-Synuclein is a major component of Lewy bodies in the brains of patients with Parkinson's disease (PD) as well as of neuronal/glial inclusions in a subset of neurodegenerative disorders collectively termed synucleinopathies. Here we studied by immunohistochemistry the accumulation of alpha-synuclein in transgenic (TG) Drosophila overexpressing wild-type (WT) or familial PD-linked mutant (i.e. A30P and A53T) alpha-synuclein in neurons, with special reference to the phosphorylation at Ser129, that is characteristic of human synucleinopathy lesions. Progressive accumulation of human alpha-synuclein was widely observed in the cell bodies and neurites of major neuronal nuclei in TG Drosophila brains, and phosphorylation of alpha-synuclein at Ser129 was detected in a limited subset of neurons approximately 1 week after alpha-synuclein immunoreactivity was first detected. Phosphorylated alpha-synuclein was most abundant in A53T mutant, followed by A30P and WT Drosophila. These results suggest that accumulation and phosphorylation of alpha-synuclein is recapitulated in neurons of alpha-synuclein transgenic Drosophila, that underscores the relevance of this model to human synucleinopatheis. 相似文献
997.
Kouzin Kamino Keiko Nagano Tomohiro Katsuya Yumiko Nishiwaki Masatoshi Takeda Hirotaka Tanabe Tsuyoshi Nishimura Kunio Ii Kenzo Fujimoto Ryotaro Tsujimura Yasuhiro Nonomura Hiroshi Yoneda Toshiaki Sakai Teruo Nakajima Masaki Imagawa George M. Martin Thomas D. Bird Gerard S. Schellenberg Tetsuro Miki Toshio Ogihara 《Journal of human genetics》1995,40(3):229-241
Summary Linkage and haplotype analysis of eleven early-onset Alzheimer disease (AD) families was performed in relation to D21S210 and microsatellite DNA polymorphisms localized on chromosome 14q24.3. Linkage analysis of eight informative families out of eleven early-onset AD families disclosed the highest LOD score of 3.45 (=0.00) at D14S77, while the locus of /A4 amyloid protein precursor gene was formally excluded within 10 cM from D21S210, given the evidence of recombinations in five families. Transmission disequilibrium study between the patients and controls without dementia indicated significant differences at D14S43 (p=0.0001) and D14S71 (p=0.02). Association study between genotypes linked or related to onset of AD and those of control also revealed a significant difference at D14S43 (p<0.05), suggesting the existence of linkage disequilibrium. Moreover, the haplotypes at D14S43 linked with the onset of AD indicated a significant relationship with the mean age at onset. These results support that the major locus of earlyonset familial AD is located on 14q24.3, and its close linkage to D14S43 and the existence of allelic heterogeneity were suggested. 相似文献
998.
Watanabe T Yamamoto T Ikegaya N Fujigaki Y Suzuki H Togawa A Fukasawa H Nagase M Hishida A 《The Journal of pathology》2002,198(3):397-406
Increases in transforming growth factor-beta (TGF-beta) expression and extracellular matrix accumulation are transient in acute self-limited mesangial proliferative glomerulonephritis induced by a single injection of anti-thymocyte serum (ATS), while these increases persist following repeated injections that produce chronic progressive sclerosing glomerulonephritis with tubulointerstitial lesions. However, little is known about the expression of TGF-beta receptors (TbetaRs) in cells involved in the proliferative and sclerosing renal lesions. A study of protein and mRNA expression for type I (TbetaRI), type II (TbetaRII), and type III (TbetaRIII) TbetaR in both forms of nephritis was therefore carried out by immunohistochemistry and in situ hybridization. Inhibition of cell proliferation and stimulation of matrix production by TGF-beta1 were assessed in isolated glomeruli using [(3)H]thymidine incorporation and [(3)H]proline metabolic labelling, respectively. In acute self-limited nephritis, expression of TbetaRI, TbetaRII, and TbetaRIII increased in the glomerular and Bowman's capsular epithelial cells comprising the glomerular tuft adhesions to Bowman's capsules. However, TbetaRII expression was not prominent in proliferating mesangial cells. Glomeruli isolated from rats with acute self-limited nephritis at day 7, when mesangial cell proliferation was maximal, were partially resistant to the mitoinhibitory effects of TGF-beta1. In contrast, expression of all three TbetaRs was elevated in glomerular and tubulointerstitial lesions in chronic progressive nephritis, and glomeruli isolated from rats with chronic progressive nephritis 7 days after the second ATS injection were sensitive to TGF-beta1. These data suggest that distinct cellular responses to TGF-beta1 resulting from differential expression of TbetaR underlie the difference between acute self-limited mesangial proliferative and chronic progressive sclerosing ATS nephritis in the development of proliferative and sclerotic renal lesions. 相似文献
999.
Regional vulnerability to chronic hypoxia and chronic hypoperfusion in the rat brain 总被引:1,自引:0,他引:1
Chikako Kawaguchi Shunya Takizawa Kiyoshi Niwa Tokuzen Iwamoto Ichiro Kuwahira Hirotaka Kato Yukito Shinohara 《Pathophysiology》2002,8(4):379-253
The purpose of this study was to compare the pathological findings of injury induced by chronic hypoperfusion and by chronic hypoxia in rat brain. Adult male Wistar rats were divided into three groups: chronic hypoperfusion (n=5), chronic hypoxia (n=5), and normal control groups (n=5). Hypoperfusion was induced by ligation of the bilateral carotid arteries under 2.5% halothane anesthesia. Chronic hypoxia was induced by keeping the animals in a chamber with an atmosphere of 10% O2 in N2 for 3 weeks. Twelve weeks later (chronic hypoperfusion group) and 3 weeks later (chronic hypoxia group), the animals were sacrificed and perfused through the femoral artery with a fixative containing 4% paraformaldehyde. Hematoxylin and eosin staining was done in all sections in the three groups, and the number of normal-appearing cells was counted. Normal-appearing cells in CA3 were significantly decreased in the chronic hypoperfusion group compared with those in the chronic hypoxia group, although neurons in CA1, CA2 and CA4 in both groups were equally damaged. We concluded that the CA3 hippocampus shows different vulnerabilities to chronic hypoperfusion and chronic hypoxia, possibly owing to a difference in the kinds of glutaminergic receptors. 相似文献
1000.
Payano M Kondo Y Kashima K Daa T Yatsuka T Kida H Nakayama I Yokoyama S 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2004,112(2):141-147
Clear cell meningioma is a rare disorder. We report two cases of nondura-based clear cell meningioma of the cauda equina, one in a 24-year-old male and the other in a 19-year-old female. Both patients had complained of numbness and spontaneous pain in the lower back and limbs for several months. Magnetic resonance imaging and computed tomography scanning revealed an intradural tumor in the cauda equina in each case. At surgery, a neurilemoma was suspected, because each of the tumors had displaced nerve roots and had attached to one of the nerve roots without any adherence to the dura. Light microscopy revealed that both tumors were well-demarcated with a thin capsule and consisted mainly of clear, glycogen-rich, polygonal cells with vague whorl formations, and of copious deposits of hyalinized blocky collagen in the stroma and perivascular areas. The neoplastic cells were immunopositive for vimentin and epithelial membrane antigen, but immunonegative for S-100 protein and chromogranin A. Positive nuclei for MIB-1 were very few in both cases, and PCNA-labeling indices were 12.1% and 24.7%, respectively. No local recurrence has been seen for 61 months and for 52 months, respectively. 相似文献