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21.
H M Kim S Hirota H Onoue T Hirata K Suzuki S Ohno T Kuroki Y Kitamura S Nomura 《Brain research. Developmental brain research》1992,70(2):239-244
The expression and localization of a novel protein kinase C delta (nPKC delta) mRNA were investigated using Northern blotting and in situ hybridization in the developmental process of mouse brain. In adult mice, nPKC delta was abundantly expressed in the thalamus, moderately in the pons and the cerebellum, but faintly in the cerebral cortex and the spinal cord. By in situ hybridization, the signals were observed specifically at the sensory and motor relay nuclei of the thalamus, the dorsal cochlear nuclei of the pons, and the molecular layer of the cerebellum. When developmental changes in the expression of nPKC delta gene were analyzed by in situ hybridization, it was not detectable in embryonic and neonatal brains, very weakly expressed in the thalamus in the first week, and highly expressed at two weeks of age. These results suggest that the gene expression of nPKC delta is strictly controlled by both the cell type and the developmental process. 相似文献
22.
A sensitive enzyme-linked immunosorbent assay (ELISA) was used in a retrospective study of placental alkaline phosphatase (PLAP) levels in serum, cerebrospinal fluid (CSF), and intratumoral cyst fluid in primary intracranial germinoma. The ELISA showed no cross-reactivity with intestinal alkaline phosphatase except in very high concentrations, after samples had been heat-treated. Three patients with germinoma were studied for serum PLAP levels and in all the levels were elevated (3.78, 0.52, and 2.11 IU/liter). Two of the germinoma patients were studied for PLAP levels in the CSF, and both had elevated levels (0.83 and 9.83 IU/liter). The intratumoral cyst fluid in one case of germinoma was tested for PLAP and the level was found to be very high (603 IU/liter). These PLAP levels decreased concomitantly with the reduction in tumor size during irradiation. Serum PLAP levels were measured in 40 control adult male individuals and in the CSF of 20 nonpregnant patients with subarachnoid hemorrhage. The upper normal limits were 0.20 and 0.11 IU/liter in the serum and the CSF, respectively. All PLAP levels measured in the serum of patients with various brain tumors were 0.18 IU/liter or less. This study strongly suggests that PLAP is a clinically useful tumor marker for primary intracranial germinoma. 相似文献
23.
Arg60 to Leu mutation of the human thromboxane A2 receptor in a dominantly inherited bleeding disorder. 总被引:7,自引:2,他引:5
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T Hirata A Kakizuka F Ushikubi I Fuse M Okuma S Narumiya 《The Journal of clinical investigation》1994,94(4):1662-1667
Recent advances in molecular genetics have revealed the mechanisms underlying a variety of inherited human disorders. Among them, mutations in G protein-coupled receptors have clearly demonstrated two types of abnormalities, namely loss of function and constitutive activation of the receptors. Thromboxane A2 (TXA2) receptor is a member of the family of G protein-coupled receptors and performs an essential role in hemostasis by interacting with TXA2 to induce platelet aggregation. Here we identify a single amino acid substitution (Arg60-->Leu) in the first cytoplasmic loop of the TXA2 receptor in a dominantly inherited bleeding disorder characterized by defective platelet response to TXA2. This mutation was found exclusively in affected members of two unrelated families with the disorder. The mutant receptor expressed in Chinese hamster ovary cells showed decreased agonist-induced second messenger formation despite its normal ligand binding affinities. These results suggest that the Arg60 to Leu mutation is responsible for the disorder. Moreover, dominant inheritance of the disorder suggests the possibility that the mutation produces a dominant negative TXA2 receptor. 相似文献
24.
Yoshimitsu Kuroyanagi DR. ENG DR. SCI DR. MED ; Akihiko Shiraishi MD ; Yoshiteru Shirasaki MD ; Nobuaki Nakakita MD ; Yoshiaki Yasutomi MD ; Yasuo Takano MD ; Nobuyuki Shioya MD FACS 《Wound repair and regeneration》1994,2(2):122-129
A bilaminar wound dressing composed of an outer membrane and an inner three-dimensional matrix of a fabric or a sponge may be considered to constitute an ideal structure that promotes wound healing: the outer membrane prevents body fluid loss, controls water evaporation, and protects the wound surface from bacterial invasion, and the inner matrix encourages adherence by tissue growth into the matrix. Using this concept, we developed a biosynthetic wound dressing with a drug delivery capability. This medicated wound dressing is composed of a spongy sheet of a chitosane derivative and collagen mixture that is laminated to an antimicrobial-impregnated polyurethane membrane. In this study, a gentamycin sulfate-impregnated wound dressing was prepared and evaluated. The antimicrobial efficacy of this wound dressing was examined on an agar plate seeded with Pseudomonas aeruginosa. Also, the cytotoxicity of an antimicrobial released from this wound dressing was examined in an in vitro system with cultured skin substitutes. Both in vitro tests have shown that this wound dressing is capable of suppressing bacterial growth and minimizing cellular damage. In addition, in the treatment of wounds inflicted on rats and rabbits, this wound dressing was shown to be efficacious in covering full-thickness and split-thickness skin defects. Finally, the efficacy of this wound dressing was evaluated in a nonrandomized open-label study of 31 clinical cases. In 31 cases treated with this wound dressing, good or excellent wound healing was achieved. 相似文献
25.
Tumor vascularity under angiotensin II-induced hypertension--angiographic observations 总被引:1,自引:0,他引:1
The selective increase in tumor blood flow under angiotensin II-induced hypertension was observed to be the result of passive vascular beds irresponsive to angiotensin II. We investigated whether or not increased tumor blood flow resulting from angiotensin II-induced hypertension could be recognized on angiographic findings. Angiography under angiotensin II-induced hypertension was performed in 51 patients with various cancers, and angiographic findings indicating increased tumor vascularity were recognized in 40 (78.4%) of them. Based on the assumption that the increase in tumor oxygen tension was brought about by increased tumor blood flow, the possibility of utilizing this phenomenon in hyperbaric oxygenation radiotherapy was suggested. 相似文献
26.
Yuki Mawatari Akira Hirata Mikiko Fukushima Hidenobu Tanihara 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2006,244(8):1056-1059
Purpose To evaluate quantitative choroidal dye filling velocity in patients with Vogt-Koyanagi-Harada disease (VKH) before and after corticosteroid treatment using indocyanine green (ICG) angiography.Methods ICG angiography was performed in seven VKH patients before and after systemic corticosteroid treatment. Choroidal dye curves were obtained by image analysis software and analyzed using an exponential model. The model’s time constant (τ) was used to evaluate choroidal dye filling velocity.Results Compared with controls, acute phase choroidal τ values in VKH patients were significantly longer, suggesting choroidal circulation disturbance. During the recovery phase, choroidal τ values were significantly shortened, suggesting choroidal circulatory disturbance improvement.Conclusion Choroidal dye filling velocity may be useful for VKH diagnosis and verification of corticosteroid treatment effectiveness. 相似文献
27.
Takahide Nagashima Hideaki Tanaka Masafumi Ito Koichi Hirata Soichi Katayama Kazuo Watanabe 《Clinical neurology》2006,46(1):40-44
We report a patient of relapsing polychondritis (RP) with antecedent aseptic meningitis. A 65-year-old man has developed headache and fever. Neurological examination showed meningeal signs, and cerebrospinal fluid (CSF) examination revealed meningeal inflammation which contained 450 polymorphonuclear cells/microl, 302 mononuclear cells/microl, and 0 red cells/microl, with 79 mg protein/dl. Serologic testing for autoimmune disease as well as the culture and cytology of CSF were negative. He admitted our hospital as having aseptic meningitis and experienced antibiotic therapy. However, his pyrexia continued and he developed repeating visual and hearing impairment reacting to steroid. Three months later, he became behaviorally deaf, and bilateral auricular chondritis occurred with nonerosive seronegative inflammatory polyarthritis. The result of condral biopsy was consistent with the diagnosis of RP showing cartilage surrounded by an intense inflammatory cell response with a decreased number of chondrocytes. A clinical diagnosis was made and prednisolone 60 mg/day was begun with the result of resolution of the auricular chondritis, and slight improvement of his deafness. Aseptic meningitis is a rare complication of RP. Only one report detailed RP patient who had preceding meningitis. RP is a potentially lethal disease resulting from suffocation by airway collapse, the complications of a cardiac large vessel, and so on. For improvement of a life prognosis, an early diagnosis and treatment are indispensable. Although RP is a rare discovery, it is necessary that RP should be taken into consideration and be differentiated as a cause of relapsing aseptic meningitis. 相似文献
28.
Wheat germ agglutinin-horseradish peroxidase conjugate was injected in the unilateral superior cervical ganglion (SCG), and the projection pathways of postganglionic sympathetic nerve fibers innervating the cochlea were traced in the rat. The labeled axons advanced along the internal carotid artery (ICA), and a few advanced caudally in the major petrosal nerve (MPN) and entered the facial nerve, while the majority ran rostral to the pterygopalatine ganglion at the point where they crossed the MPN in the carotid canal. The rest of the labeled fibers remained on the surface of the ICA and advanced to the cranial cavity. Most of the labeled fibers along the facial nerve joined the cochlear nerve and finally reached the osseous spiral lamina through the spiral ganglion. Some of the labeled fibers ran along the anterior inferior cerebellar artery from the basilar artery which was previously thought to have been the only pathway. We could not find any labeled fiber on the modiolar artery from anterior inferior cerebellar artery in the cochlea. These observations are consistent with our hypothesis that the sympathetic fibers innervating the neural tissues or related structures follow nerve fibers and meninges as matrices of projection pathways rather than arteries. 相似文献
29.
Shigeki Yamagishi Kiyoshi Koizumi Tomomi Hirata Kyoji Hirai Jiro Kurita Kazuo Shimizu 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(6):313-316
We report a 59-year-old woman who underwent thoracoscopic extirpation of the intrapulmonary cystic lymphangioma which was located in the subpleural space of the left upper lobe. A chest X-ray showed a solitary round nodule in the left pulmonary hilum. A computed tomography scan revealed a mass shadow at the interlobar region surrounding the interlobar pulmonary artery. A round nodule was recognized as low signal intensity on T1-weighted images by magnetic resonance imaging. There was biphasic signal intensity on T2-weighted images as well. Radiologically, we diagnosed this lesion as a benign cystic tumor in the lung. Thoracoscopic observation revealed a cystic lesion just beneath the visceral pleura of the upper lobe adjacent to the interlobular pulmonary artery. As this suggested a benign bronchogenic cyst, we performed extirpation of the cyst under thoracoscopy. After this operation, the cyst was diagnosed as an intrapulmonary cystic lymphangioma pathologically. 相似文献
30.
Haruhiko Ogawa Masaki Fujimura Motoyasu Saito Tamotsu Matsuda Nobuaki Akao Kaoru Kondo 《Clinical autonomic research》1994,4(1-2):19-28
Eosinophilic bronchitis without asthma can cause a persistent non-productive cough which is resistant to bronchodilator therapy. To understand the mechanism of the cough in this disorder, an animal model of eosinophilic bronchitis was developed. Guinea-pigs were treated with transnasal administration of polymyxin B or saline twice a week for 3 weeks. The number of eosinophils in bronchoalveolar lavage fluid increased in polymyxin B-treated animals when compared with those treated with saline. In addition, histological examination showed that the number of eosinophils infiltrated into the tracheal epithelium increased; injury to the tracheal epithelium was greater in polymyxin B-treated animals. The numbers of coughs induced by saline and each concentration of capsaicin (10–18, 10–16, 10–14M) were greater in the polymyxin B-treated animals. FK-224 (a neurokinin receptor antagonist) decreased the heightened cough reflex in this animal model of eosinophilic bronchitis. These findings suggest that neuropeptides, and particularly neurokinins, are involved in the heightened cough receptor sensitivity in eosinophilic bronchitis without asthma. This has implications for better understanding of this disorder and its treatment. 相似文献