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61.
Okamoto M Hayatsu K Tomita M Shimoji K 《Masui. The Japanese journal of anesthesiology》2002,51(8):916-920
We report here the management of labor for a 33-year-old woman with Marfan's syndrome. She was diagnosed as Marfan's syndrome at the age of 5 and experienced corrective surgery for abdominal aortic aneurysm at 28 years of age. As there was no progression of cardiovascular lesion, she was allowed to be pregnant. She was planned to proceed with vaginal delivery, since she was in trouble of circulation during her gestational period. In order to prevent catastrophe such as aortic dissection or aortic regurgitation elicited by hypertension related with labor pain, we performed continuous epidural anesthesia to control labor pain under the invasive blood pressure monitoring. Two epidural catheters were inserted into the epidural space via the L 2-3 and the L 5-S 1 intervertebral space, and mixed solutions containing both 0.125% bupivacaine and 0.0002% fentanyl were administered continuously. After 7 hours and 47 minutes from the start of her labor, she delivered her baby vaginally with the aid of forceps technique due to attenuated abdominal muscle activity. No cardiovascular mishaps occurred during her labor and she was discharged 6 days after the delivery. Thus, continuous epidural anesthesia with intensive monitoring of circulation may be useful for vaginal delivery in a patient with Marfan's syndrome by avoiding cardiovascular complications due to labor pain. 相似文献
62.
CD3-zetachain expression of intratumoral lymphocytes is closely related to survival in gastric carcinoma patients 总被引:7,自引:0,他引:7
Ishigami S Natsugoe S Tokuda K Nakajo A Higashi H Iwashige H Aridome K Hokita S Aikou T 《Cancer》2002,94(5):1437-1442
BACKGROUND: Impaired or reduced CD3 zeta chain (CD3-zeta) expression in T cells has been identified in various cancers and may be associated with an ineffective immune response. The clinical significance of CD3-zeta chain expression in tumor-infiltrating lymphocytes (TILs) in gastric carcinoma remains unclear. METHODS: The authors immunohistochemically investigated CD3-zeta expression in TILs in 185 patients who had undergone curative gastrectomy. CD3-zeta/CD3 epsilon (CD3-epsilon) ratios were calculated. Patients were divided into two groups: a normal CD3-zeta group (n = 121) and a reduced CD3-zeta group (n = 64). Patients with a zeta per epsilon ratio of greater than 66% were placed in the normal CD3-zeta group. RESULTS: Patients in the normal CD3-zeta group had fewer lymph node metastasis (P < 0.01) and a shallower depth of invasion (P < 0.05) than those in the reduced CD3-zeta group. The 5-year survival rate was 72% in the normal CD3-zeta group, which was significantly better than that in the reduced CD3-zeta group (55%; P < 0.01). When stratified according to clinical stage, the prognostic value was significantly different only in Stage IV patients. Multivariate analysis showed that CD3-zeta expression was an independent prognostic factor (P = 0.03) next to depth of invasion and lymph node involvement. CONCLUSIONS: Reduced CD3-zeta expression in TILs was strongly correlated with progressive disease in gastric carcinomas. CD3-zeta expression in TILs is considered an immunologic, independent prognostic marker in gastric carcinoma patients. CD3-zeta normalization with cytokine treatment may lead to prolonged survival in advanced gastric carcinoma patients. 相似文献
63.
Cyclooxygenase-2 inhibition by celecoxib reduces proliferation and induces apoptosis in angiogenic endothelial cells in vivo 总被引:39,自引:0,他引:39
Cyclooxygenase-2 (COX-2) is expressed within neovascular structures that support many human cancers. Inhibition of COX-2 by celecoxib delays tumor growth and metastasis in xenograft tumor models as well as suppresses basic fibroblast growth factor 2 (FGF-2)-induced neovascularization of the rodent cornea. The present studies were undertaken to evaluate possible mechanisms of the antiangiogenic and anticancer effects of celecoxib. Prostaglandin E(2) (PGE(2)) and thromboxane B(2) (TXB(2)) were increased in rat corneas implanted with slow-release pellets containing FGF-2 (338.6 ng of PGE(2)/g and 17.53 ng of TXB(2)/g) compared with normal rat corneas (63.1 ng of PGE(2)/g and 2.0 ng of TXB(2)/g). Celecoxib at 30 mg/kg/day p.o. inhibited angiogenesis (78.6%) and prostaglandin production by 78% for PGE(2) (72.65 ng/g) and 68% for TXB(2) (5.55 ng/g). Decreased prostaglandin production in corneas was associated with a 2.5-fold cellular increase in apoptosis and a 65% decrease in proliferation. Similar reductions in proliferation were observed in neovascular stroma (65-70%) of celecoxib-treated (dietary 160 ppm/day) xenograft tumors as well as in tumor cells (50-75%). Apoptosis was also increased in the tumor cells (2.2-3.0-fold) in response to celecoxib. Thus, the antitumor activity of celecoxib may be attributable, at least in part, to a direct effect on host stromal elements, such as the angiogenic vasculature. 相似文献
64.
High seizure susceptibility in El mice is associated with disinhibition in the dentate gyrus (DG) and paired-pulse facilitation in the CA3 area in hippocampal slices [Brain Res. 745 (1997) 165; Brain Res. 779 (1998) 324]. A decrease in gamma-aminobutyric acid (GABA)-mediated inhibition and an increase in excitatory inputs to the major neurons seem to be the responsible mechanisms, respectively, for these phenomena. In this study, we examined the effects of tiagabine, an inhibitor of GABA transporter, on hyperexcitation in vivo and in slice preparations. Tiagabine (0.3-0.5 mg/kg) suppressed the occurrence of seizures to about 20% of controls with an ED(50) value of about 0.17 mg/kg. In addition, perfusion of hippocampal slices with tiagabine (20 microM) counteracted the paired-pulse facilitation in the CA3 region over the entire range of interpulse intervals (P<0.05, two-way ANOVA) and reduced the disinhibition in the DG measured at 10 and 20 ms during short interpulse intervals (P<0.005, paired t-test). The CA1 region in the El mice, as well as in a non-epileptic parental strain of ddY mice did not respond to the drug. However, frequency potentiation of CA3 was enhanced in both strains (P<0.05, paired t-test). Our results suggest that within the hippocampus the antiepileptic action of tiagabine is selectively suppressive for hyperexcitability of DG and CA3, which are responsible for seizure-susceptibility in El mice. 相似文献
65.
66.
P-Glycoprotein Is Positively Correlated with p53 Protein Accumulation in Human Colorectal Cancers 总被引:5,自引:0,他引:5
Mikio Oka Kiyoshi Kounoura Fumihiko Narasaki Akira Sakamoto Minoru Fukuda Isao Matsuo Koki Ikeda Junji Tsurutani Nobuhiro Ikuno Katsuhisa Omagari Yohei Mizuta Hiroshi Soda Jean M. Gudas Shigeru Kohno 《Cancer science》1997,88(8):738-742
To explore the relationship between mutant p53 and Pgp expression, we have examined the levels of both proteins in human colorectal adenocarcinomas. Serial frozen sections of 40 surgical samples were stained with an anti-Pgp (MRK16) and two different anti-p53 protein antibodies (Abs), PAb421 and Pabl80l. Nineteen (47.5%) of 40 samples examined were positive for Pgp, and 18 (45%) of 40 were positive for p53. The samples that stained positively with PAb421 also stained positively with Pahl80l. Pgp expression was detected in 13 (76.5%) of 17 samples that were positive for p53 using PAb421 and in 15 (83.3%) of 18 samples that were positive for p53 using Pabl80. Thus, we found that p53 and Pgp were co-expressed in a significant number of samples ( P < 0.002). There was no relationship between Pgp or p53 protein accumulation and histologic grade or stage. The present results demonstrate that Pgp expression is closely associated with p53 protein accumulation in human colorectal cancers. These data provide evidence to support the idea that mutant p53 activates the MDR1 gene in vivo . 相似文献
67.
Role of cyclooxygenases in angiogenesis 总被引:5,自引:0,他引:5
Angiogenesis is the process by which new blood vessels are formed. This process supports normal physiology as well as contributes to progression of disease. Progressive rheumatoid arthritis and growth of tumors are two pathologies to which angiogenesis contributes. In arthritis, we know that prostaglandins (PGs) and the enzyme cyclooxygenase-2, which catalyses prostaglandin production, are inflammatory mediators. These mediators are involved in rheumatoid arthritis and cancer-induced angiogenic processes. We discuss, herein, recent findings on the expression of cyclooxygenases in both rheumatoid arthritis and human cancer, and the links between COX-2, PGs, and angiogenesis. We also propose a model for the possible mechanistic interaction of the various cell types involved in angiogenesis. 相似文献
68.
69.
Tanaka H Namekata I Takeda K Kazama A Shimizu Y Moriwaki R Hirayama W Sato A Kawanishi T Shigenobu K 《Naunyn-Schmiedeberg's archives of pharmacology》2005,371(6):526-534
The functional role of the sodium–calcium exchanger in mouse ventricular myocardium was evaluated with a newly developed specific inhibitor, SEA0400. Contractile force and action potential configuration were measured in isolated ventricular tissue preparations, and cell shortening and Ca2+ transients were measured in indo-1-loaded isolated ventricular cardiomyocytes. SEA0400 increased the contractile force, cell shortening and Ca2+ transient amplitude, and shortened the late plateau phase of the action potential. -adrenergic stimulation by phenylephrine produced a sustained decrease in contractile force, cell shortening and Ca2+ transient amplitude, which were all inhibited by SEA0400. Increasing the contraction frequency resulted in a decrease in contractile force in the absence of drugs (negative staircase phenomenon). This frequency-dependent decrease was attenuated by SEA0400 and enhanced by phenylephrine. Phenylephrine increased the Ca2+ sensitivity of contractile proteins in isolated ventricular cardiomyocytes, while SEA0400 had no effect. These results provide the first pharmacological evidence in the mouse ventricular myocardium that inward current generated by Ca2+ extrusion through the sodium–calcium exchanger during the Ca2+ transient contributes to the action potential late plateau, that -adrenoceptor-mediated negative inotropy is produced by enhanced Ca2+ extrusion through the sodium–calcium exchanger, and that the negative staircase phenomenon can be explained by increased Ca2+ extrusion through the sodium–calcium exchanger at higher contraction frequencies. 相似文献
70.
Sonoyama K Watanabe H Watanabe J Yamaguchi N Yamashita A Hashimoto H Kishino E Fujita K Okada M Mori S Kitahata S Kawabata J 《The Journal of nutrition》2005,135(3):538-543
We recently found that dietary raffinose suppressed allergic airway eosinophilia in ovalbumin-sensitized Brown Norway rats. Using this model in the present study, we compared the efficacy of other oligosaccharides with that of raffinose. Brown Norway rats were immunized s.c. with ovalbumin on d 0 and exposed to aerosolized ovalbumin on d 20; broncho-alveolar lavage fluid was obtained on d 21. In Expt. 1, rats were fed a control diet or diets supplemented with different oligosaccharides (50 g/kg diet, raffinose, alpha-linked galactooligosaccharide, fructooligosaccharide, and xylooligosaccharide). The number of eosinophils in the fluid was significantly lower in rats fed raffinose and alpha-linked galactooligosaccharide diets than in those fed the control diet. Dietary fructooligosaccharide and xylooligosaccharide did not affect airway eosinophilia. In Expt. 2, i.p. administration of raffinose and alpha-linked galactooligosaccharide, but not fructooligosaccharide and xylooligosaccharide, suppressed airway eosinophilia in rats fed the control diet. In Expt. 3, suppression of airway eosinophilia by dietary alpha-linked galactooligosaccharide occurred in cecectomized rats administered neomycin. Reduced levels of interleukin (IL)-4 and IL-5 mRNA in lung tissue were associated with the suppression of airway eosinophilia. We propose that indigestible oligosaccharides differ in their suppressive effect on allergic airway eosinophilia in ovalbumin-sensitized Brown Norway rats and that the effect appears not to be mediated by intestinal microflora. 相似文献