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991.
Analysis of the temporal expression of nestin in human fetal brain derived neuronal and glial progenitor cells 总被引:7,自引:0,他引:7
Messam CA Hou J Berman JW Major EO 《Brain research. Developmental brain research》2002,134(1-2):87-92
Nestin expression in the developing human brain was examined with the use of unique human specific anti-nestin antibodies. Double immunostaining of cell cultures and tissue sections derived from first and second trimester human fetal brain (HFB) examined the co-expression of nestin with other cell type specific phenotypic markers. The immunocytochemical analysis shows that from first to second trimester, the majority of developing glial cells exhibited a transitional state marked by co-expression of nestin and GFAP. However, the corresponding transitional state for developing neuronal cells, co-expressing nestin and MAP-2, was rarely detected. These results imply different temporal patterns of nestin expression in cells of glial and neuronal lineages. Confocal microscopy of HFB tissue section staining also revealed a similar pattern of nestin co-expression with glial and neuronal markers. Our results suggest that nestin expression alone may not identify an undifferentiated stem cell, and that progenitor cells in glial and neuronal lineages express nestin in different temporal patterns. 相似文献
992.
Programmed cell death (apoptosis) is critical for the normal development and homeostasis of the immune system. There is increasing evidence that dysregulations of apoptotic pathways are associated with autoimmune disease, including multiple sclerosis (MS). Cellular commitment to apoptosis is partly regulated by the Bcl-2 family proteins, which includes the death antagonists Bcl-2 and Bcl-X(L), and death agonists Bax and Bad. Since the role of these proteins in the pathogenesis of MS is currently unknown, we analyzed their expression profile in peripheral and intrathecal lymphocytes from MS patients and appropriate controls. We observed a significant reduction in the expression ratios of pro-apoptotic to anti-apoptotic Bcl-2 members in both peripheral and intrathecal lymphocytes from MS patients when compared to corresponding ratios in patients with inflammatory or noninflammatory neurologic controls, or healthy individuals. The relative coexpression ratios of these pro- and anti-apoptotic Bcl-2 family proteins in MS were more significant than the expression of individual members. The low cellular expression ratios of pro-apoptotic proteins in MS were confirmed in vitro activated T lymphocytes. Cellular expression of Bcl-2, Bcl-X(L), Bax or Bad in MS patients was independent of the expression of other apoptotic regulatory molecules, such as Fas receptor protein or FLIP. Our findings suggest that the abnormal expression patterns of Bcl-2 family proteins in MS may promote apoptotic resistance of potentially pathogenic, autoreactive lymphocytes, and may allow for continuing cellular proliferation and tissue destruction within the central nervous system. 相似文献
993.
Wang E Lacelle C Xu S Zhao X Hou M 《The journals of gerontology. Series A, Biological sciences and medical sciences》2002,57(11):B400-B405
The recognition that multigene mechanisms control the pathways determining the aging process renders gene screening a necessary skill for biogerontologists. In the past few years, this task has become much more accessible, with the advent of DNA chip technology. Most commercially available microarrays are designed with prefixed templates of genes of general interest, allowing investigators little freedom of choice in attempting to focus gene screening on a particular thematic pathway of interest. This report describes our "designer microarray" approach as a next generation of DNA chips, allowing individual investigators to engage in gene screening with a user friendly, do-it-yourself approach, from designing the probe templates to data mining. The end result is the ability to use microarrays as a platform for versatile gene discovery. 相似文献
994.
Wang JY Hsieh JS Chen FM Lee LW Hou MF Huang YS Huang TJ 《The Kaohsiung journal of medical sciences》2002,18(3):146-148
Routine pelvic drainage after resection of the rectum followed by immediate anastomosis is not only advisable but also essential for decreasing fluid accumulation and subsequent abscess formation. In spite of infrequency, complications secondary to placement of these surgical drains occur. Herein we report two cases of rectal perforation caused by prophylactic drainage of pelvic cavity after low anterior resection for rectal carcinoma. Postoperatively, both patients were found with discharge of faecal material from the surgical drains. Anastomotic dehiscence was tentatively impressed until a definite diagnosis was obtained. The drain tube penetrated into the rectal lumen without anastomotic leakage and that was ultimately confirmed by colonoscopy. The possibility of rectal perforation should be kept in mind when draining the pelvic cavity after low anterior resection for the rectal carcinoma. Furthermore, significance of colonoscopy in the early postoperative period should be emphasized. 相似文献
995.
Establishment of a simple assay in vitro for hepatitis C virus NS3 serine protease based on recombinant substrate and single—Chain protease 总被引:6,自引:0,他引:6
AIM: To establish a simple and convenient assay in vitro for the Hepatitis C virus NS3 serine protease based on the recombinant protease and substrate, and to evaluate its feasibility in screening the enzyme inhibitors. METHODS: Based on the crystallographic structure of hepatitis C virus (HCV) serine protease, a novel single-chain serine protease was designed, in which the central sequence of cofactor NS4A was linked to the N-terminus of NS3 serine protease domain via a flexible linker GSGS. The fusion gene was obtained by two-step PCR that was carried out with three primers and then cloned into the prokaryotic expression vector pQE30, and the recombinant clone was verified by DNA sequencing. The single-chain recombinant protease was expressed when the E.coli was induced with IPTG and the expression conditions were optimized to produce large amount of soluble protease. The recombinant substrate NS5ab that covers the cleavage point NS5A/B was also expressed in E.coli. Both of the protease and substrate were purified by using Ni-NTA agarose metal affinity resin, then they were mixed together in a specific buffer, and the mixture was analyzed by SDS-PAGE. The cleavage system was used to evaluate some compounds for their inhibitory activity on serine protease. RESULTS: The single-chain recombinant protease was over-expressed as soluble protein when the E.coli was induced at a low dosage of IPTG (0.2 mM) and cultured at a low temperature (15 degrees ). The protease was purified by using Ni-NTA agarose metal affinity resin (the purity is over 95 %). The recombinant substrate NS5ab was expressed in an insoluble form and could refold successfully after purification and dialysis. A simple and convenient assay in vitro was established, in which the purified single-chain serine protease could cleave the recombinant substrate NS5ab into two fragments that were visualized by SDS-PAGE. PMSF had an effect on inhibiting activity of serine protease, while EDTA had not. CONCLUSION: A simple and convenient assay in vitro for hepatitis C virus NS3 serine protease is based on recombinant substrate NS5ab and single-chain serine protease. This assay can be used in screening of enzyme inhibitors. 相似文献
996.
Effects of somatostatin and octreotide on portal-systemic collaterals in portal hypertensive rats 总被引:6,自引:0,他引:6
Huang HC Lee FY Chan CC Chang FY Wang SS Lin HC Hou MC Chen CT Tai CC Lai IN Lee SD 《Journal of hepatology》2002,36(2):163-168
BACKGROUND/AIMS: Somatostatin and its long-acting analogue, octreotide, have been used to cease variceal bleeding with uncertain mechanisms. This study investigated whether somatostatin and octreotide have a direct vasoconstrictive effect on the portal-systemic collaterals of portal-hypertensive rats and potentiate the vasoconstriction induced by endothelin-1 in these vascular beds. METHODS: The vascular responses of collateral vessels to graded concentrations of somatostatin (10(-9)-10(-5) mol/l), octreotide (10(-10)-10(-6) mol/l), norepinephrine (10(-9)-10(-5) mol/l) and vehicle (Krebs solution) were evaluated in perfused collateral vascular beds of rats with portal hypertension induced by partial portal vein ligation. In addition, the perfusion pressure changes of collateral vessels to endothelin-1 (10(-8) mol/l) in the presence of vehicle(control), somatostatin (10(-6) mol/l) and octreotide (10(-6) mol/l) were tested. RESULTS: Compared with the vehicle group, norepinephrine significantly increased the perfusion pressure of collateral vessels at concentrations between 10(-7) and 10(-5) mol/l. In contrast, neither somatostatin nor octreotide significantly changed the perfusion pressure. Somatostatin and octreotide significantly enhanced the endothelin-1-induced vasoconstrictive effect on the collaterals. CONCLUSIONS: Somatostatin and octreotide exert no direct vasoconstrictive effect on the collateral vessels of portal hypertensive rats. In the presence of endothelin-1, somatostatin and octreotide exert a local vasoconstrictive effect on these vascular beds. 相似文献
997.
998.
999.
Hou MF Lin GT Tang CS Chu YL Liu HC Huang TJ Chao YY Yang CY 《The American surgeon》2002,68(9):808-811
The dust from the vaporized tissue released during a mastectomy presents a hazard to the patients and the operating room personnel. More dust has been noted using the conventional electrocautery pencil in dissecting breast tissue than with the metal knife used in the past. It is very important to reduce the hazardous dust released during mastectomy. For this study 80 patients undergoing mastectomy for breast cancer from March to June 2001 were divided into two groups: 1) those whose dissections were performed with a combination of an electrocautery pencil and suction with an intravenous infusion catheter (40 cases) and 2) those whose dissections were performed with the conventional method in which the electrocautery pencil was handled by the surgeon and the metal suction tube was used separately by an assistant (40 cases). During mastectomy the personal air sampler was affixed to the operator's neck to collect the dust from the vaporized tissue. The concentrations of the total dust were significantly lower in the combined electrocautery-suction method (mean 5.56 +/- 3.26 microg/m3) than in the conventional method (mean 34.81 +/- 4.83 microg/m3) during mastectomy (P < 0.05). Although the operating time and blood loss were less in the combined method than in the conventional method this difference was not statistically significant (P > 0.05). The combined method of using the electrocautery pencil for dissecting breast tissue along with the intravenous infusion catheter reduced the concentrations of the total dust from the vaporized tissue plume. Furthermore this method reduces the hazards of dust to the surgeons and operating room personnel. Additionally the cost of this combined method is lower than that of the conventional method. 相似文献
1000.
目的探讨酒依赖病人的个性特点和相应的护理干预。方法采用中科院心理研究所修订的MMPI—R问卷,对121例酒依赖病人进行个性分析。结果酒依赖病人个性特点为被动依赖、对人疏远、自我为中心、情绪不稳、自控力差、易激惹、低自尊、有反社会行为、焦虑、记忆力减退等。结论针对酒依赖病人个性特点,恰当的护理干预,能使病人早日脱瘾,全面康复。 相似文献