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41.
Autosomal dominant neovascular inflammatory vitreoretinopathy 总被引:1,自引:0,他引:1
S R Bennett J C Folk A E Kimura S R Russell E M Stone E M Raphtis 《Ophthalmology》1990,97(9):1125-35; discussion 1135-6
Twenty-eight of 61 members of a six-generation family are affected by an autosomal dominant eye disease which has not been described previously. Affected patients are asymptomatic in early adulthood, but have vitreous cells and the selective loss of the b-wave on the electroretinogram. Later, peripheral retinal scarring and pigmentation, peripheral arteriolar closure, and neovascularization of the peripheral retina at the ora serrata or occasionally neovascularization of the optic disc develop. Cystoid macular edema, vitreous hemorrhage, tractional retinal detachment, and neovascular glaucoma can cause profound visual loss. Vitrectomy reduces traction on the retina and allows for retinal reattachment. The role of argon laser photocoagulation or cryopexy in reducing the neovascular complications remains uncertain. 相似文献
42.
M. Nakamura Michitaka Ozaki Shohei Fuchinoue Satoshi Teraoka Kazuo Ota 《Transplant international》1997,10(2):89-95
Ischemia-reperfusion injury by free radicals and lipid peroxides is observed in various organs. Ascorbic acid (AsA) or glutathione
(GSH) in various doses (AsA:2, 0.5, 0.1 mmol/kg, GSH:2 mmol/kg) was intraperitoneally administered to male Wistar rats. The
entire small intestines were resected just before ischemia, after ischemia, and after 20 min of reperfusion (n = 7–10 at each time point). At each time point, the specimens were subjected to assays of lipid peroxides, GSH, and glutaminase
activity of the tissues; they were also examined histologically. In the AsA group, the production of lipid peroxides after
reperfusion was significantly suppressed in a dose-dependent manner, and the ratio of oxidized GSH to total GSH was also significantly
low. Tissue glutaminase activity decreased to a lesser extent, and the degree of injury was apparently less marked in the
AsA group. This study indicates that AsA acts as an antioxidant against peroxidative tissue injury, possibly by scavenging
radicals, preserving reduced GSH, and reducing the peroxidative reaction.
Received: 21 June 1996 Received after revision: 8 October 1996 Accepted: 12 November 1996 相似文献
43.
Acetylcholinesterase activity and pseudocholinesterase activity were examined in plasma and in striated muscles (whole heart and diaphragm muscles) of diabetic KK-CAy mice. Both activities of acetylcholinesterase in heart muscle and pseudocholinesterase in plasma were significantly increased in diabetic KK-CAy mice compared to pre-diabetic KK-CAy mice. Both acetylcholinesterase and pseudocholinesterase activities in skeletal muscle were not changed by the diabetic state. The increases in activity of plasma pseudocholinesterase was significantly correlated to the increase in blood glucose level in alloxan-, streptozotocin (STZ)-diabetic ddY mice and diabetic KK-CAy mice. The increase was not correlated to the body weight in non-diabetic female-KK-CAy mice. Furthermore, the activity of heart acetylcholinesterase was significantly correlated with the activity of plasma pseudocholinesterase (r = 0.79, P less than 0.01). The activities of acetylcholinesterases in heart muscles from STZ- and alloxan-diabetic ddY mice also tended to increase. The hypersensitivity of the pulse rate to a low dose (1 mg/kg) of acetylcholine was correlated to the activity of plasma pseudocholinesterase (r = -0.51, P less than 0.05). These results demonstrate that the activities of plasma pseudocholinesterase were increased by the diabetic state being associated with the increasing alteration of cardiac sensitivity to acetylcholine in the whole body. 相似文献
44.
45.
Michiko Oka Y. Itoh Shigeru Tatsumi F.-H. Ma Yojiro Ukai Yoshiaki Yoshikuni Kiyoshi Kimura 《Naunyn-Schmiedeberg's archives of pharmacology》1997,356(2):189-196
The effect of (+)-5-oxo-D-prolinepiperidinamide monohydrate (NS-105), a novel cognition enhancer, on adenylate cyclase activity
was investigated in cultured neurons of the mouse cerebral cortex. NS-105 (10–7 and 10–6 M) inhibited forskolin-stimulated cyclic AMP formation, an action that was dependent on pertussis toxin-sensitive G proteins.
Conversely, in pertussis toxin-pretreated neurons, NS-105 (10–7 –10–5 M) significantly enhanced the forskolin-stimulated cyclic AMP formation, and this action was completely reversed by cholera
toxin. A metabotropic glutamate receptor agonist (1S, 3R)-1-aminocyclopentane-1, 3-dicarboxylic acid (1S, 3R-ACPD) produced
similar bi-directional actions on the cyclic AMP formation. Both of these inhibitory and facilitatory actions of NS-105 and
1S, 3R-ACPD were blocked by L(+)-2-amino-3-phosphopropinoic acid (L-AP3). NS-105 (10–6 M) and 1S, 3R-ACPD (10–4 M) significantly enhanced isoproterenol- and adenosine-stimulated cyclic AMP formation. The enhancement of such Gs-coupled
receptor agonists-stimulated cyclic AMP formation was also produced by quisqualate but not by L(+)-2-amino-4-phosphonobutanoate
(L-AP4). The phosphoinositides hydrolysis was enhanced by 1S, 3R-ACPD (10–4 M) but not by NS-105 (10–6 M), however, 1S, 3R-ACPD-induced increase in phosphoinositides turnover was attenuated by NS-105. These findings suggest
that NS-105 stimulates metabotropic glutamate receptor subclasses that are coupled both negatively and positively to adenylate
cyclase, but it acts as an antagonist at the receptor subclasses that are linked to phosphoinositides hydrolysis.
Received: 3 February 1997 / Accepted: 25 April 1997 相似文献
46.
Kohji Matsushita Kazuo Kitagawa Tomohiro Matsuyama Toshiho Ohtsuki Akihiko Taguchi Kenji Mandai Takuma Mabuchi Yoshiki Yagita Takehiko Yanagihara Masayasu Matsumoto 《Brain research》1996,743(1-2)
The divalent cation zinc has been reported to possess several physiological properties such as blocking apoptotic cell death through an inhibitory effect on Ca2+-Mg2+ endonuclease activity, or modulating the neurotoxicity via glutamate receptor subtypes. In the present study, we investigated the effect of peripherally injected zinc on delayed neuronal death seen in the hippocampus after transient global ischemia, in order to elucidate a possible beneficial role on zinc in ischemic neuronal cell death. Forty-five adult Mongolian gerbils of both sexes underwent transient bilateral clipping of the common carotid arteries for 3 min. In the pretreated animals, ZnCl2 (20 mg/kg) was injected subcutaneously once, 1 h before ischemia (superacute group; n=6) or twice at 24 and 48 h before ischemia (subacute group; n=14). Histological survey was carried out 3 days later by in situ DNA fragmentation method and 4 days later by hematoxylin-eosin staining by semiquantatively counting dead neurons in the CA1 sector. Subacute zinc pre-administration significantly reduced the nuclear damage and subsequent neuronal death; however, superacutely pre-administered zinc did not protect hippocampal neurons against ischemia but it did not aggravate the effect of ischemia, either. The present study suggested that transfer of exogenous zinc into the intracellular space is required for neuroprotection, presumably via the anti-endonuclease activity. 相似文献
47.
Hiroshi Ujike Kazuo Tsuchida Kazufumi Akiyama Yutaka Fujiwara Shigetoshi Kuroda 《Pharmacology, biochemistry, and behavior》1995,50(4):613-617
The ontogeny of the behavioral effects of acute cocaine administration and behavioral sensitization to cocaine in rat pups was investigated. Acute behavior stimulating effects of cocaine were observed in pups as young as 7 postnatal days (PND) old, although they needed a higher dose of cocaine than adult rats to evoke the same motor effects. An adult dose-response curve pattern of stereotypy and locomotion to acute cocaine treatment was observed at PND 21, and of rearing at PND 28. Rats aged PND 7, 14, 21, 28, and 56 received repeated injections of saline or cocaine (15 mg/kg) twice a day for 5 consecutive days. After a 3-week period of abstinence, sensitization to a challenge dose of cocaine was assessed. Cocaine-induced stereotyped behavior was enhanced significantly only in rats in which cocaine pretreatment was initiated on PND 21, 28, and 56, but not earlier on PND 7 and 14. Adult female rats given repeated cocaine injections on PND 56–60 showed significantly greater sensitization than males, but no such sex difference was observed in pups given cocaine repeatedly on PND 21–25 or 28–32. These results show clearly that cocaine-induced behavioral sensitization in rats occurred only when subchronic cocaine administration was commenced on PND 21 or later. 相似文献
48.
49.
Takayoshi Ogawa Akinobu Gotoh Atsushi Takenaka Isao Hara Kazuo Gohji Soichi Arakawa Osamu Matsumoto Sadao Kamidono 《Cancer chemotherapy and pharmacology》1992,30(Z1):S66-S71
We have treated advanced transitional-cell carcinoma of the urothelial tract with methotrexate, vinblastine, Adriamycin, and cisplatin (M-VAC) chemotherapy since July of 1985. We analyzed the effect of that chemotherapy in 26 patients with advanced urothelial cancer who were treated in our hospital and followed up. They were divided into two groups. Group 1 consisted of 15 patients with distant metastases. In all, 11 of them received M-VAC as adjuvant chemotherapy for metastatic lesions after surgical removal of the primary lesion, and the remaining 4 patients were not operable since they had very advanced-stage tumors; they received only M-VAC chemotherapy. Group 2 contained 11 patients who received M-VAC neo-adjuvant chemotherapy. In group 1, the overall response rate was 57.1% and the mean duration of response was 12.6 months. In the 11 patients who had received M-VAC as adjuvant therapy after surgical removal of the primary tumor, the mean duration of response was 14.1 months. After M-VAC chemotherapy, six patients underwent surgical resection of metastatic lesions and restaging was done pathologically in these cases. The clinical response coincided with the pathological response in all six cases. In group 2,5 of 11 patients experienced histological downstaging of the resected bladder. M-VAC chemotherapy combined with surgical resection of residual tumors has proved to be an effective option against advanced urothelial cancer.Presented at the 4th International Conference on Treatment of Urinary Tract Tumors with Adriamycin/Farmorubicin, 16–17 November 1990, Osaka, Japan 相似文献
50.
ASTROCYTE-CONDITIONED MEDIUM INDUCES BLOOD-BRAIN BARRIER PROPERTIES IN ENDOTHELIAL CELLS 总被引:6,自引:0,他引:6