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101.
Jun Anabuki Masatoshi Hori Hiroshi Ozaki Iwao Kato Hideaki Karaki 《European journal of pharmacology》1990,190(3):373-379
The mechanism of the vasodilator effect of pinacidil was examined. Pinacidil (0.1–100 μM) inhibited the increases in cytosolic Ca2+ ([Ca2+]i) and muscle tension due to norepinephrine in rat aorta. In contrast, a Ca2+ channel blocker, verapamil, inhibited the norepinephrine-stimulated [Ca2+]i more strongly than the contraction. Higher concentrations of pinacidil (3–100 μM) inhibited the verapamil-insensitive portion of the contraction and [Ca2+]i. An inhibitor of ATP-sensitive K+ channels, glibenclamide, antagonized the inhibitory effect of low concentrations ( 10 pM) of pinacidol. Pinacidil did not change the contraction induced by Ca2+ in vascular smooth muscle permeabilized with Staphylococcus aureus -toxin. Norepinephrine (in the presence of GTP), 12-deoxyphorbol 13-isobutyrate (in the absence of GTP), and treatment with GTPγS potentiated the contraction of permeabilized smooth muscle induced by the addition of Ca2+. Pinacidil (100 μM) inhibited the potentiation due to GTPγS or noepinephrine but not to phorbol ester. These results suggest that pinacidil has dual effects on vascular smooth muscle contraction. At lower concentrations (>0.1 μM), it decreases [Ca2+]i, possibly by activating ATP-sensitive K+ channels. At higher concentrations (> 3 μM), it may additionally inhibit the receptor-mediated, GTP-binding protein-coupled phosphatidyl inositol turnover. 相似文献
102.
Kentaro Yamashita Hiroyuki Tsukuda Yasuyo Mizukami Jun Ito Shigeo Ikuta Yoshihiro Kondo Hiroshi Kinoshita Yasunori Fujisawa Kohzoh Imai 《Journal of gastroenterology》1997,32(5):684-688
A case of hepatic infarction with portal thrombosis is reported. A 63-year-old woman with liver cirrhosis and esophageal varices
was admitted for treatment of the esophagel varices. Endoscopic variceal ligation (EVL) and endoscopic injection sclerotherapy
(EIS) were performed. Two months later, she experienced right hypochondralgia and right flank pain. Serum transaminase levels
were suddenly elevated, and computed tomography scans of the liver showed multiple small nodular lesions. Her condition worsened,
and she died of hepatic failure. Autopsy revealed splenic and portal vein thrombosis, multiple hepatic infarction, and evidence
of chronic pancreatitis. We believe that liver cirrhosis and chronic pancreatitis were the main risk factors for the portal
thrombosis, and the treatment for esophageal varices appeared to have triggered the thrombosis. The hepatic infarction was
caused by the portal thrombosis. 相似文献
103.
We studied choline acetyltransferase (CAT) activity in a rat model of brachial plexus injury. In experiment 1, we found that the CAT activity was remarkably high in the anterior roots and low in the posterior roots. In experiment 2, nerve root segments were extracted and examined for CAT activity in the root avulsion group (group A) and the plexus severance group (group B). CAT activity decreased day by day in group A, reaching about 1/20 of the normal 5 days postoperatively. By contrast, in group B activity decreased only slightly, and even at 90 days postoperatively was about 6,000 cpm (one-half normal level). As a result, CAT activity enabled us to distinghish postganglionic from preganglionic injury of the cervical roots. Furthermore, it was a useful adjunct for minimizing nerve loss in intercostal nerve transfer, distinguishing motor and sensory branches of the intercostal nerve, and evaluating the motor nerve activity. © 1995 Wiley-Liss, Inc. 相似文献
104.
Hiroshi Uno Yoshihiro Izawa Kiyoshi Sagara Tamotsu Koyama Tokutaro Makita Chia-Yuan Hsu-Chang Mitsugi Sugiyama 《Journal of bone and mineral metabolism》1990,8(1):10-16
The effect of 1α-hydroxyvitamin D3 (1α(OH)D3) on the metabolic bone disorders developed in gastrectomized rats were investigated biochemically and histomorphologically.
1α(OH)D3 was suspended in 0.2 % Triton-X-100 aqueous solution after dissolving in a very small amount of ethanol, was given orally
to the rats for 10 weeks. The sham operated animals and the gastrectomy control animals received the vehicle alone. Gastrectomy
was followed by the development of the metabolic bone disorders after 10 weeks of observation. This was characterized by reduction
in ash content of the femur and histologically by a disappearance of the trabecular bone in tibial metaphysis. Decrease Ca
absorption from the intestines was demonstrated by a radiotracer technique. Biochemical studies showed significant decreases
in serum 25(OH)D concentration in gastrectomized rats. These findings suggest that gastrectomy partially impairs intestinal
absorption of calcium and results in a negative calcium balance, which may contribute to the development of bone metabolic
disorders in rats. The administration of 1α(OH)D3 increased dose-dependently serum calcium and Ca absorption from the intestine and prevented the development of bone metabolic
disorders histomorphologically. 相似文献
105.
Shigeki Ohgitani Akimitsu Miyauchi Yasuyuki Takagi Yoshio Fujii Takuo Fujita Misa Nakamura Zhi-qiang Zhang Liang Shan Mitsuyo Sasaki Ryuichi Tsukino Toyoharu Yokoi Kennichi Kakudo Tomitaka Nakayama Junya Toguchida Hiroshi Kanoe Shinichi Aizawa Masao S. Sasaki Takashi Nakamura M. Suda K. Tanaka Y. Ogawa N. Tamura A. Yasoda H. Itoh M. Uehira N. Nishimoto T. Takigawa K. Shiota K. Nakao 《Journal of bone and mineral metabolism》1997,15(3):165-171
106.
Masanori Hisaoka Takatoshi Aoki Hiromi Kouho Hirofumi Chosa Hiroshi Hashimoto 《Skeletal radiology》1997,26(3):191-194
The case of a 49-year-old man with Maffucci’s syndrome, who developed multiple spindle cell hemangioendotheliomas, is presented.
The case provides support for recent reports suggesting an association between this peculiar vascular lesion and skeletal
enchondromatosis. 相似文献
107.
Tsuyoshi Satoh Tadashi Watanabe Masanori Tadokoro Junichi Sakamoto Hiroki Murayama Katsuki Itoh Sadayuki Sakuma Hiroshi Takagi 《Cancer science》1992,83(4):379-386
Anti-carcinoembryonic antigen monoclonal antibody (MAb) CEA102 was produced by immunization with purified CEA and the specific accumulation of radiolabeled CEA102 in colorectal cancers was investigated by autoradiography of surgical specimens using Fuji Computed Radiography (FCR). Five patients with colorectal cancer were injected intravenously with 131 I-labeled intact CEA102 or its F(ab')2 . Primary tumor and liver metastases were successfully detected by external scanning with a gamma camera in 4 cases. Autoradiographic study of the surgical specimens using FCR showed predominant localization of 131 I-labeled CEA102 in primary tumors and liver metastases in all cases. Even a small liver metastasis (0.5 cm) was clearly visualized in the autoradiogram by FCR. The pixel distribution curves of the density of the respective tissues in the autoradiograms by FCR showed the heterogeneity of the distribution of administered radiolabeled MAb in individual tumors, but the density of the tumors was higher than that of the normal tissues. In the quantitative distribution analysis of CEA102, the uptake of the primary tumor (mean 1.10%ID/kg) was ten-fold greater than that of the normal colon mucosa (mean G.10%ID/kg). These results revealed that the application of MAb has great potential in radioimmunodetection as well as in antibody-directed therapy. 相似文献
108.
Naoya Emoto Eiji Ohmura Osamu Isozaki Toshio Tsushima Kazuo Shizume Hiroshi Demure 《Clinical endocrinology》1991,34(5):377-382
In order to study the mechanism of GH secretion from somatotroph adenoma cells, we have compared the effect of 12–O-tetradecanoyl phorboi-13-acetate (TPA) with that of growth hormone releasing factor (GRF) on GH secretion from human somatotroph adenoma cells cultured in monolayer. Pituitary adenoma cells were obtained from 13 patients with acromegaly undergoing surgery. On the 7th day of culture, the cells were exposed for 2 h to secretagogues. All 13 adenoma cell cultures (100%) responded to TPA (1·6–16·0 nmol/I) with a two- to six-fold increase in GH release (240·37% Increase of control: mean±SE). The response was detectable within 10 min, and was maximal at 2 h. Phosphollpase C (7·7 mmol/I) also stimulated a two-to ten-fold Increase In GH release in all four adenomas examined (100%). GH release was stimulated by GRF (2·0 nmol/I) in eight out of 12 adenoma cells (67%), but the magnitude of the responses to GRF (60·18% Increase of control: mean ± SE) were much smaller than that of TPA. Five out of 13 adenomas secreted detectable amount of PRL Into the medium and these five adenomas (100%) responded to TPA (16·0 nmol/I) with a two- to six-fold Increase. These observations indicate that the activation of protein kinase C is the consistent stimulator in GH and PRL secretion In human somatotroph adenoma cells. However, It is not determined whether the protein kinase C 相似文献
109.
Y Nomura S Miura H Koyama K Enomoto F Kasumi H Yamamoto M Kimura T Tominaga H Iino T Morimoto 《Cancer》1992,69(1):153-164
In a retrospective multicenter study to investigate the correlation between estrogen (ER) and/or progesterone receptors (PgR) in primary breast cancer with patient prognosis, 3118 patients with operable breast cancer (International Union Against Cancer Stages I, II, and III) were investigated from ten hospitals in Japan who underwent surgery from October 1972 to December 1982; 3089 were evaluable. The ER-positive and PgR-positive cancers were found in 56% and 34% of patients, respectively. The positivities decreased as the tumor size increased but were independent on lymph node metastasis. There were no significant differences in relapse-free survival (RFS) in relation to receptor status (median follow-up, 89 months [ER], 84 months [PgR]). However, in patients with four or more positive nodes, those with PgR-positive cancer had a longer RFS. The patients with ER-positive cancer survived significantly longer than ER-negative ones, with the greatest difference seen in those with four or more positive nodes. There was a significantly longer postrelapse survival (PRS) for patients with ER-positive cancer because of the different distribution of the major metastasis and better responses to first-line and subsequent treatments. Cox's multivariate analysis showed that overall survival but not PRS was affected by ER (and more weakly by PgR) because of the longer PRS in patients with ER-positive cancer. 相似文献
110.
Adipose tissues differentiated by adipose-derived stem cells harvested from transgenic mice 总被引:2,自引:1,他引:1
Objective: To induce adipocyte differentiation in vitro by adipose-derived stromal cells (ASCs) harvested from transgenic mice with green fluorescent protein (GFP) and assess the possibility of constructing adipose tissues via attachment of ASCs to typeⅡcollagen scaffolds. Methods: Inguinal fat pads from GFP transgenic mice were digested by enzymes for isolation of ASCs (primary culture). After expansion to three passages of ASCs, the cells were incubated in an adipogenic medium for two weeks, and the adipocyte differentiation by ASCs in vitro was assessed by morphological observation and Oil Red O staining. Then they were attached to collagen scaffolds and co-cultured for 12 hours, followed by hypodermic implantation to the dorsal skin of nude mice for 2 months. The newly-formed tissues were detected by HE staining. Results: The cultured primary stem cells were fibroblast-like and showed active proliferation. After being incubated in an adipocyte differentiation medium, the lipid droplets in the cytoplasm accumulated gradually and finally developed into mature adipocytes, which showed positive in Oil Red O staining. A 0. 5-cm3 new tissue clot was found under the dorsal skin of the nude mice and it was confirmed as mature adipose tissues by fluorescent observation and HE staining. Conclusions: ASCs can successfully differentiate adipose tissues into mature adipocytes, which exhibit an adipocyte-like morphology and express as intracytoplasmic lipid droplets. It is an efficient model of adipose tissues engineered with ASCs and type I collagen scaffolds. 相似文献