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71.
Ozawa H Chancellor MB Jung SY Yokoyama T Fraser MO Yu Y de Groat WC Yoshimura N 《The Journal of urology》1999,162(6):2211-2216
PURPOSE: This study was conducted to examine effects of nitric oxide (NO) donors on bladder hyperactivity induced by cyclophosphamide (CYP)-induced cystitis. MATERIALS AND METHODS: Female Sprague-Dawley rats received a single intraperitoneal injection of CYP (100 mg./kg.), and then their micturition pattern including mean micturition volume and the number of micturitions during 24 hours was recorded in a metabolic cage before and after CYP treatment. Forty-eight hours after CYP injection, bladder function under urethane anesthesia was evaluated by cystometry with continuous saline infusion (0.04 ml. per minute) or under isovolumetric conditions (0.8 ml. bladder volume). NO donors, S-nitroso-N-acetyl-penicillamine (SNAP, 2 mM) or sodium nitroprusside (SNP, 1 mM), and an NO synthase (NOS) inhibitor, N-nitro-L-arginine methyl ester (L-NAME, 20 mM) were administered intravesically. Direct action of SNAP on bladder afferent neurons was also tested in a patch-clamp recording study. RESULTS: The number of micturitions significantly increased during the first 24 hours after CYP injection (19.0 +/- 0.88 versus 92.1 +/- 16.3 micturitions/24 hours, mean +/- SE, n = 25) (p <0.001). There was no significant difference in total micturition volume before (12.3 +/- 1.0 ml./24 hours) and after CYP treatment (15.6 +/- 1.5 ml./24 hours). During continuous infusion cystometry, intercontraction interval (ICI) was smaller in CYP-injected rats than in control rats. In CYP-injected animals, NO donors increased the ICI, but did not change the amplitude of bladder contractions. Continuous intravesical infusion of the NOS inhibitor did not alter the cystometric parameters. During cystometry under isovolumetric conditions, contraction frequency was decreased after NO donor administration. NO donors did not influence bladder activity in control rats. In patch clamp recordings, when SNAP (500 microM) was directly applied to dissociated afferent neurons innervating the urinary bladder, high-voltage-activated Ca2+ channel currents were suppressed by approximately 30%. CONCLUSIONS: Intravesical NO donors can suppress CYP-induced bladder hyperactivity. We hypothesize that the effect of NO donors is not due to smooth muscle relaxation, but rather due to an inhibitory effect on bladder afferent pathways that was manifested by an increase in intercontraction interval without changes in contraction amplitude. NO donors may be considered as a possible treatment of CYP-induced and other types of bladder inflammation. 相似文献
72.
A 75-year-old male was hit by a car, when riding a bicycle. The diagnosis of acute epidural hematoma was made based on computed tomography (CT) findings of lentiform hematoma in the left temporal region. On admission he had only moderate occipitalgia and amnesia of the accident, so conservative therapy was administered. Thirty-three hours later, he suddenly developed severe headache, vomiting, and anisocoria just after a positional change. CT revealed typical acute subdural hematoma (ASDH), which was confirmed by emergent decompressive craniectomy. He was vegetative postoperatively and died of pneumonia one month later. Emergent surgical exploration is recommended for this type of ASDH even if the symptoms are mild due to aged atrophic brain. 相似文献
73.
Shimpo M Ikeda U Maeda Y Ueno S Ikeda M Minota S Takizawa T Urabe M Kume A Monahan J Ozawa K Shimada K 《American journal of nephrology》2000,20(3):242-247
Adeno-associated virus (AAV) vectors have a number of attractive features, including lack of cytotoxicity, ability to transduce nondividing cells, and long-term transgene expression. We investigated whether rat renal cells could be efficiently transduced with AAV vectors. Rat glomerular mesangial cells were transduced with AAV-lacZ vector containing beta-galactosidase gene in vitro, and the expression of beta-galactosidase was evaluated by X-gal staining and ELISA. For ex vivo experiments, sections of rat kidneys were incubated with AAV-lacZ, and then evaluated by X-gal histochemical staining. The level of beta-galactosidase expression in cultured rat mesangial cells increased in a dose-dependent manner (ranging from 1 x 10(5) to 5 x 10(6) particles/cell). When transduced with 5 x 10(6) vector particles/cell of AAV-lacZ, about 50% of mesangial cells were stained positively with X-gal, and the level of beta-galactosidase expression reached 9.9 +/- 1.5 ng/mg protein. Expression was detectable during the culture period for at least 7 days. X-gal histochemical examination of the ex vivo transduced renal tissue revealed tubular cell and interstitial tissue staining. However, gene transfer was not clearly observed in glomeruli. These findings suggest that AAV vectors have the potential for gene therapy of renal diseases. 相似文献
74.
The role of the sentinel lymph node in gastrointestinal cancer 总被引:38,自引:0,他引:38
Kitagawa Y Fujii H Mukai M Kubota T Ando N Watanabe M Ohgami M Otani Y Ozawa S Hasegawa H Furukawa T Kumai K Ikeda T Nakahara T Kubo A Kitajima M 《The Surgical clinics of North America》2000,80(6):1799-1809
Evaluation of the clinical significance of the sentinel node concept in GI cancer has just begun. The authors' preliminary data, using intraoperative radiation techniques and the gamma probe, suggest that it is worthwhile to continue the evaluation of this procedure to determine its role in an accurate staging and a minimally invasive approach to GI cancers. 相似文献
75.
76.
Lung autopsies from four neonates with Ebstein's anomaly or tricuspid valve dysplasia and gross cardiomegaly were examined.
The mean cardiothoracic ratio was 92 ± 0.5%. The degrees of pulmonary hypoplasia and pulmonary artery muscularization were
assessed and were compared with those in lungs from four controls and four patients with diaphragmatic hernias. Lung and body
weight ratios and radial alveolar counts, which reflect pulmonary hypoplasia and immaturity, were significantly decreased
only in patients with diaphragmatic hernia. The thickness of the medial muscle layer in small pulmonary arteries was greater
in patients with diaphragmatic hernia; however, in patients with tricuspid valve disease, it was relatively small. Abnormal
vascular muscle extension was seen only in patients with diaphragmatic hernia. In the cases of tricuspid valve disease, although
cardiomegaly and lung compression were severe, lung hypoplasia and immaturity were not, and neither abnormal medial thickening
nor extension were found. Our results suggest that, at least in full-term infants with tricuspid valve disease, surgical relief
of lung compression may improve respiratory function, even if the cardiomegaly is severe. 相似文献
77.
Genetic Alterations of Mixed Hyperplastic Adenomatous Polyps in the Colon and Rectum 总被引:1,自引:2,他引:1
Hiroyuki Uchida Hiroshi Ando Keiji Maruyama Hiroshi Kobayashi Hiroshi Toda Hiroshi Ogawa Takachika Ozawa Yasuhide Matsuda Haruhiko Sugimura Takashi Kanno Shozo Baba 《Cancer science》1998,89(3):299-306
Some mixed hyperplastic adenomatous polyps (MHAPs) contain dysplastic lesions or even carcinomas. These polyps are considered to be different from ordinary hyperplastic polyps and may have a preneoplastic potential. We investigated APC and K- ras mutations in MHAPs of the colon and rectum, and also in colorectal adenomas and hyperplastic polyps to identify molecular differences between MHAPs, adenomas and hyperplastic polyps, using direct sequencing of mutation cluster regions (MCR) in APC and K- ras . No APC mutations were identified in 12 MHAPs and 8 hyperplastic polyps, whereas 10 of 27 (37.0%) adenomas showed somatic mutations. K- ras mutations were identified in one of 12 (8.3%) MHAPs, one of 8 (12.5%) hyperplastic polyps, and 10 of 27 (37.0%) adenomas. p53 mutation was found in a carcinoma arising in an MHAP. Mutations other than APC mutations may play a role in the development of MHAPs. 相似文献
78.
Masuda H Ozawa M Kurita S Saito Y Ichinose Y 《Hinyokika kiyo. Acta urologica Japonica》2000,46(12):923-925
We investigated the clinical statistics of the operations and inpatients since the establishment of the department in June 1994 up to May 1999. The total number of inpatients was 1,269 (1,047 males and 222 females), and a total of 1,098 operations were performed. Extracorporeal shock wave lithotriopy (ESWL) was also introduced in 1997, and in addition, it seemed that the number of operations and inpatients would be increasing in future. 相似文献
79.
Clinical efficacy of heparin-bonded bypass circuits related to cytokine responses in children 总被引:5,自引:0,他引:5
Ozawa T Yoshihara K Koyama N Watanabe Y Shiono N Takanashi Y 《The Annals of thoracic surgery》2000,69(2):584-590
BACKGROUND: Cardiopulmonary bypass (CPB) induces numerous systemic reactions. This study examined the efficacy of heparin-bonded CPB circuits on inflammatory responses and postoperative status in children. METHODS: Thirty-four infants undergoing elective cardiac surgery were randomly divided into two groups: a heparin-bonded CPB group (n = 17) and a non-heparin-bonded group (n = 17). Plasma levels of the inflammatory cytokines were measured before, during, and after CPB, and postoperative status was determined by examining the respiratory index, blood loss, and the post- and preoperative body weight percent ratio. RESULTS: Significant differences in tumor necrosis factor-alpha, interleukin-6, and interleukin-8 patterns were observed during and after CPB between the two groups (p < 0.01, p < 0.01, p < 0.05, respectively). All cytokines measured were significantly lower in the heparin-bonded group just after CPB (p < 0.05). There were no differences in duration of intubation, intensive care unit or hospital stay, or postoperative blood loss, but the respiratory index 3 hours after CPB and body weight percent ratio 24 and 48 hours after CPB were significantly reduced in the bonded group (p < 0.05, p < 0.01, p < 0.05, respectively). CONCLUSIONS: Our findings suggest that heparin bonding of the bypass circuits affects early postoperative status and reduces cytokine responses in pediatric cardiac surgery. 相似文献
80.
Atsuko Koizumi Makiko Fujii Masuo Kondoh Yoshiteru Watanabe 《European journal of pharmaceutics and biopharmaceutics》2004,57(3):473-478
N-Methyl-2-pyrrolidone (NMP) increased the skin permeation of estradiol (E2) in Yucatan micropig epidermis using a modified Franz-type diffusion cell. The addition of NMP significantly increased the fluxes of E2 from water and soybean oil. The flux and skin concentration of E2 were higher from soybean oil than from water and increased with increasing NMP concentrations in soybean oil. Correlation was observed with E2 flux and skin concentration (R(2) = 0.804) NMP enhanced E2 skin permeation because NMP made E2 skin concentration higher. Thus, NMP (10%) was added to the oily gel made by isocetyl isostearate and hydrogenated phospholipid. E2 permeation from the gel without NMP was the same as that from soybean oil suspension. The flux of E2 from the gel with NMP was 0.6 microg/h per cm(2) and might be sufficient for estrogen replacement therapy. 相似文献