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141.
142.
Akt/PKB activation in gastric carcinomas correlates with clinicopathologic variables and prognosis 总被引:23,自引:0,他引:23
Nam SY Lee HS Jung GA Choi J Cho SJ Kim MK Kim WH Lee BL 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(12):1105-1113
Akt/protein kinase B (PKB) plays an important role in cell survival. However, the role of Akt in the biology of gastric cancer has not been well studied. We sought to investigate the expression of Akt or phosphorylated Akt (pAkt) in human gastric carcinomas and to analyze the relationship between Akt or pAkt and the clinicopathologic parameters. The expressions of Akt and pAkt were evaluated immunohistochemically in 311 gastric carcinomas using the tissue array method. Akt expression was detected in 74% of the tumors and pAkt expression in 78%. pAkt was highly expressed in the early stage of pTNM (p=0.011). We also found an inverse association between pAkt and lymphatic invasion (p=0.01) or lymph node metastasis (p=0.008). pAkt expression was significantly correlated with a higher survival in patients with stage I carcinomas (p=0.0003). Interestingly, combined evaluation revealed that the group with pAkt-positive and lymph node-negative carcinomas showed a better prognosis than the other groups (p<0.0001). In addition, pAkt was shown to correlate positively with APC (p=0.002) and Smad4 (p<0.0001) expression. These findings suggest that pAkt expression may help to predict the clinical outcome of gastric cancer patients. 相似文献
143.
Facilitating visuospatial attention for the contralateral hemifield by repetitive TMS on the posterior parietal cortex 总被引:2,自引:0,他引:2
Previous studies have demonstrated that repetitive transcranial magnetic stimulation (rTMS) could modulate the visuospatial functions. In this study, we investigated the effect of off-line high frequency subthreshold rTMS, when applied over the right or left posterior parietal cortex (PPC), on the visuospatial attention of the bilateral hemispaces. The subjects underwent visuospatial tasks before and immediately after receiving 1000 pulses of 10 Hz rTMS for a period of 20 min, and their responses were recorded. Our results demonstrated that the high frequency rTMS applied over the PPC produced facilitative effects on the visuospatial attention to the contralateral hemispace. The inhibitory effect to the ipsilateral hemispace was noticeable only in the left PPC. 相似文献
144.
Genipin-crosslinked gelatin microspheres as a drug carrier for intramuscular administration: in vitro and in vivo studies 总被引:1,自引:0,他引:1
Liang HC Chang WH Lin KJ Sung HW 《Journal of biomedical materials research. Part A》2003,65(2):271-282
Gelatin microspheres have been widely evaluated as a drug carrier. Nevertheless, gelatin dissolves rather rapidly in aqueous environments, making the use of the polymer difficult for the production of long-term delivery systems. This adverse aspect requires the use of a crosslinking agent in forming nonsoluble networks in microspheres. However, the use of crosslinking agents such as formaldehyde and glutaraldehyde can lead to toxic side effects owing to residual crosslinkers. In an attempt to overcome this problem, a naturally occurring crosslinking agent (genipin) was used to crosslink gelatin microspheres as a biodegradable drug-delivery system for intramuscular administration. Glutaraldehyde was used as a control. In the in vitro study, the morphology, dynamic swelling, and antienzymatic degradation of test microspheres were evaluated. In the in vivo study, the biocompatibility and degradability of test microspheres were implanted in the skeletal muscle of a rat model via intramuscular injection. The results obtained in the study suggested that crosslinking of gelatin microspheres with glutaraldehyde or genipin may produce distinct crosslinking structures. The water transport mechanism in both the glutaraldehyde- and genipin-crosslinked gelatin microspheres exhibit anomalous behavior ranging from Fickian to Case-II extremes. The increase of the swelling diameter for the genipin-crosslinked microspheres was significantly less than that observed for the glutaraldehyde-crosslinked microspheres. In the animal study, it was found that the degree in inflammatory reaction for tissues implanted with the genipin-crosslinked microspheres was significantly less than that implanted with the glutaraldehyde-crosslinked microspheres. Additionally, the degradation rate of the genipin-crosslinked microspheres was significantly slower than their glutaraldehyde-crosslinked counterparts. These results indicated that the genipin-crosslinked gelatin microspheres may be used as a long-acting drug carrier for intramuscular administration. 相似文献
145.
In vitro cellular immune responses to recombinant antigens of Mycobacterium avium subsp. paratuberculosis
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Shin SJ Chang CF Chang CD McDonough SP Thompson B Yoo HS Chang YF 《Infection and immunity》2005,73(8):5074-5085
Five recombinant antigens (Ags; 85A, 85B, 85C, superoxide dismutase [SOD], and 35-kDa protein) were purified from Mycobacterium avium subsp. paratuberculosis and evaluated for their ability to stimulate peripheral blood mononuclear cells (PMBCs) from fecal-culture-positive cows (low and medium shedders) and culture-negative healthy cows. Recombinant Ags 85A, 85B, and 85C induced significant lymphocyte proliferation as well as the production of gamma interferon (IFN-gamma), interleukin-2 (IL-2), IL-12, and tumor necrosis factor alpha (TNF-alpha), but not IL-4, from low and medium shedders. The 85 antigen complex did not stimulate PMBC proliferation from culture-negative healthy cows. The 35-kDa protein also induced significant lymphocyte proliferation as well as the production of IFN-gamma and IL-4 from low and medium shedders. CD4(+) T cells and CD25(+) (IL-2R) T cells were stimulated the most by 85A and 85B, while the 35-kDa protein primarily stimulated CD21(+) B cells involved in humoral immune responses. Interestingly, SOD was less immunostimulatory than other antigens but strongly induced gammadelta(+) T cells, which are thought to be important in the early stages of infection, such as pathogen entry. These data provide important insight into how improved vaccines against mycobacterial infections might be constructed. 相似文献
146.
Lee YJ Nam SW Seo DW Ahn SH Ko YK Sung DS Han JW Hong SY Lee HW 《Archives of pharmacal research》1997,20(3):239-246
In the present study, liver regeneration rate (%) was increased up to 70% 3 days after partial hepatectomy (PH). Nitric oxide
synthase (NOS) activity in liver tissue as well as serum nitrite/nitrate content had no timed response, revealing no significant
difference between shamoperated and partially hepatectomized rat liver. Contents of free methylarginines in liver tissue were
increased biphasically in a time-dependent manner after PH. However, those in serum did not exhibit the same patterns as in
liver. Taken together, the results suggest that NG-monomethyl-L-arginine (MMA) and NG, NG-dimethylarginine (DMA) play a role in inhibiting nitric oxide (NO) synthesis in regenerating rat liver because the increase
of their contents was synchronized with NOS expression. 相似文献
147.
By human intestinal bacteria, saikosaponin c was transformed to four metabolites, prosaikogenin E1 (E1) prosaikogenin E2 (E2), prosaikogenin E3 (E3) and saikogenin E. Metabolic time course of saikosaponin c was as follows; in early time, saikosaponin c was converted to E1 and E2, and then these were transformed to saikogenin E via E3. Also, this metabolic pathway was similar to the metabolism of saikosaponin c by rat intestinal bacteria.Bacteroides JY-6 andBacteroides YK-4, the bacteria isolated from human intestinal bacteria, could transform saiko-saponin c to E via E1 (or E2) and E3. However, these bacteria were not able to directly transform E1 and E2 to saikogenin E. Naringin was mainly transformed to naringenin by human intestinal bacteria. The minor metabolic pathway transformed naringin to naringenin via prunin. By JY-6 or YK-4, naringin was metabolized to naringenin only via prunin. 相似文献
148.
Twenty seven plant extracts were selected on the basis of ancient literature search for rheumatoid arthritis or similar syndrome. Methanol extract of each plant was prepared and administered orally to rats everyday at a dose of 200 mg/kg/day. Experimental arthritis was induced by subplantar injection of heat-killedMycobacterium butyricum to right hind paw of rats. This treatment provoked swelling of the treated paw in two phases, acute primary swelling and secondary arthritic swelling. An inhibition of secondary swelling was considered to be antiarthritic activity. Several plant methanol extracts such asAkebia quinata (caulis),Ephedra sinica (herba) andSophorae subprostrata (radix) were found to show significant inhibitory activity against secondary swelling at the dose tested. Our results strongly suggested an antiarthritic potential of these plant extracts. 相似文献
149.
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