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81.
Osamu Sakai Yasuhide Nakayama Yasushi Nemoto Yoshihiro Okamoto Taiji Watanabe Keiichi Kanda Hitoshi Yaku 《Journal of artificial organs》2005,8(2):119-124
A novel sutureless vascular connecting system, an assembly with a delivery rod, an introducing sheath, and a connecting device, was developed for easy implantation of small-caliber vascular grafts less than 2 mm in internal diameter. A microporous stainless tube (length 2 mm, external diameter 1.6 mm, wall thickness 65 µm, pore diameter 400 µm, pore-to-pore distance 500 µm) was designed to serve as a connecting device. The feasibility of the system was tested using two types of preliminary animal experiments. One animal model consisted of graft implantation into the rat abdominal aorta (1.5 mm in diameter). The connecting device was inserted into the proximal and distal ends of the aorta through the introducing sheath by pushing the delivery rod with the connecting device placed over it. Subsequently, the aortic segments were inserted into both ends of model grafts made of segmented polyurethane (1.8 mm in internal diameter) and were fixed with banding silk threads from the exterior. The procedure was completed within 20 min without requiring specialized microsurgery techniques. Blood leakage and obstruction did not occur. The second model consisted of an end-to-end anastomosis between rabbit common carotid arteries (2 mm in diameter), which was performed within several minutes of blood flow interruption. Scanning electron microscopy demonstrated that the luminal surface of the device was fully covered with endothelial cells (ECs) after 1 week as a result of transluminal ingrowth of native ECs through the micropores in the device. This endothelialization may prevent early thrombus-induced occlusion. This simple and “easy-to-learn” technique will promote the development of small-caliber arterial grafts, and furthermore, it may have potential for clinical application. 相似文献
82.
Endothelium-dependent vasodilation in type II diabetes mellitus 总被引:3,自引:0,他引:3
Furuta M Tsunoda K Arita M Nanjo K Sanke T 《Rinsho byori. The Japanese journal of clinical pathology》2003,51(11):1111-1115
Endothelial dysfunction is a major feature of atherosclerosis and it can also serve as an early atherosclerotic marker. Evaluation and assessment of the endothelial function is important to prevent serious atherosclerotic disease especially myocardial infarction, cerebrovascular disease and renal failure. To evaluate endothelial function we measured endothelium-dependent vasodilation (flow-mediated dilatation: %FMD) of the brachial artery with ultrasound. This method is non-invasive and can be repeatable in order to follow patients individually. Progressive atherosclerosis is often observed in diabetic patients who are not hypertensive. To evaluate the impairment of the endothelial function in type 2 diabetic patients, we examined %FMD in them and compared with hypertensive patients without diabetes and control subjects. We found that type 2 diabetic patients had the same endothelial dysfunction as hypertensive patients without diabetes. %FMD in both diabetic patients and hypertensive patients was lower than in control subjects. Moreover, %FMD of type 2 diabetic patients with hypertension was lower than %FMD of type 2 diabetic patients without hypertension. These finding suggests that endothelial dysfunction develops under the conditions of hypertension and hyperglycemia. Evaluating endothelial function with ultrasound is useful for assessment of atherosclerosis in diabetes. 相似文献
83.
Jun Nakayama Kiyohiko Angata Edgar Ong Tsutomu Katsuyama Minoru Fukuda 《Pathology international》1998,48(9):665-677
Polysialic acid is a developmentally regulated carbohydrate composed of a linear homopolymer of a-2,a-linked sialic acid residues. This unique glycan is mainly attached to the neural cell adhesion molecule (N-CAM) and implicated in many morphogenic events of the neural cells by modulating the adhesive property of N-CAM. Recently, the cDNA that encodes polysialyltransferase, which is responsible for the polysialylation of N-CAM, was successfully cloned from three mammalian species. This review focuses on the molecular cloning of human polysialyltransferase, designated PST. it then describes the number of enzymes actually required for the polysialylation of N-CAM using an in vitro polysialyltransferase assay. Comparisons between PST and another polysialyltransferase, sialyltransferase X (STX), are made and it Is demonstrated that both enzymes can independently form polysiatic acid In vitro , but that during neural development they coordinately but distinctly synthesize polysialic acid on N-CAM. The role of polysialic acid in the central nervous system is also discussed. Finally, evidence that the two polysialyltransferases, PST and STX, apparently have distinct roles in the development of neural cells is provided by using a neurite outgrowth assay. 相似文献
84.
Mutational screening of APP gene in patients with early-onset Alzheimer disease utilizing mismatched PCR-RFLP 总被引:1,自引:0,他引:1
Yumiko Nishiwaki Kouzin Kamino Aoi Yoshiiwa Keiko Nagano Masatoshi Takeda Hirotaka Tanabe Tsuyoshi Nishimura Toshiko Kobayashi Hideki Yamamoto Yasuhiro Nonomura Hiroshi Yoneda Toshiaki Sakai Masaki Imagawa Tetsuro Miki Toshio Ogihara 《Clinical genetics》1996,49(3):119-123
To elucidate the frequency of mutations of the β/A4 amyloid protein precursor (APP) gene in early-onset Alzheimer disease, we designed a mismatched PCR-RFLP that can identify all kinds of missense mutations at codon 717 in addition to the seven kinds of known mutations at exon 17. When we screened mutations at exon 17 utilizing this method and the double missense mutations at exon 16 of the APP gene by PCR-RFLP, no cases revealed mutations of the APP gene among 13 familial and 54 sporadic cases, except one family (OS-1) that had previously been reported and used as a positive control of APP717(Val → Ile). Our results support the hypothesis that mutations in the APP gene are not major causes in early-onset Alzheimer disease. 相似文献
85.
H Yamashita S Noguchi N Murakami R Kato M Adachi S Inoue S Kato I Nakayama 《Acta pathologica japonica》1990,40(10):705-712
Effects of dietary iodine on the induction of thyroid carcinoma using N-nitrosobis(2-hydroxypropyl)amine (BHP) were studied. Male Wistar rats were fed with an iodine-adequate diet (IAD group), an iodine-rich diet (IRD group) and an iodine-deficient diet (IDD group), respectively, until the time of sacrifice. From the 2nd experimental month, animals were injected with BHP once a week for 10 weeks. In the IAD and IRD groups, benign nodules and papillary carcinoma were found. The incidence of rats with benign nodules was 100% in both groups and animals with papillary carcinoma in the IAD and IRD groups comprised 33% and 29%, respectively. The area of the thyroid gland occupied by nodular lesions was much narrower in the IRD group than in the IAD group. In the IDD group, the thyroid showed marked enlargement due to multiple nodular proliferation of follicle cells. The incidence of rats with carcinoma was 100%, and not only papillary but also follicular carcinoma and one pulmonary metastasis were found. As the iodine content of the diet decreased, the nodular lesions increased in width and number, and the incidence of carcinoma in rats became higher. These effects of dietary iodine are probably related to the goitrogenic and/or promoting effects of TSH. 相似文献
86.
Networks generating locomotor-like rhythmic motor activity are formed during the last week of the fetal period in the rat spinal cord. We investigated the coordinated rhythmic motor activity induced in transverse slice preparations of the lumbar spinal cord taken from fetal rats as early as embryonic day (E) 16.5. In slices as thin as 100 microm, bath-application of 5-hydroxytryptamine (5-HT) induced rhythmic [Ca(2+)](i) elevations in motoneurons labeled with Calcium Green-1 dextran. The rhythmic [Ca(2+)](i) elevations were similar in frequency to that in the intact lumbar spinal cord, although there was no temporal correlation between the activity in the left and right sides of 100-microm slices. Such rhythmic [Ca(2+)](i) elevations were observed in the slices taken from all lumbar segments. Moreover, the rhythmic activity was abolished by simultaneous blockade of glutamate, glycine, and GABA(A) receptors, indicating that synaptic transmission mediated by these receptors is important for the generation of the rhythm in these slices. Synchronous rhythmic activity between the left-right sides was found in slices thicker than 200 microm taken from any segmental level of the lumbar spinal cord. In these preparations, commissural neurons were activated synchronously with ipsilateral motoneurons. These results indicate that the neuronal networks sufficient to generate coordinated rhythmic activity are contained in one-half of a single lumbar segment at E16.5. Such spinal cord slices are a promising experimental model to investigate the neuronal mechanisms and the development of rhythm generation in the spinal cord. 相似文献
87.
Yoshimitsu Fukushima Keiko Wakui Toshiro Nishida Yasuo Ueoka 《American journal of medical genetics. Part A》1991,40(4):485-487
We report on a boy with the blepharophimosis sequence and de novo, apparently balanced reciprocal translocation between 3q23 and 4p15.2 [46, XY,t(3;4)(q23;p15.2)de novo]. Possible assignment of this autosomal dominant disorder is discussed. A 3q23 band is a more preferable gene locus of the blepharophi mosis sequence, based on the comparison of clinical manifestations between 4p- and 3q-syndromes. 相似文献
88.
Site-specific mutagenesis of Clostridium perfringens alpha-toxin: replacement of Asp-56, Asp-130, or Glu-152 causes loss of enzymatic and hemolytic activities. 总被引:3,自引:0,他引:3 下载免费PDF全文
The current study has investigated the role of D-56, D-130, and E-152 in zinc ion binding properties, as well as the hemolytic, phospholipase C (PLC), and sphingomyelinase (SMase) activities of Clostridium perfringens alpha-toxin, based upon crystallography studies of the Bacillus cereus PLC, which had suggested these residues might be important for these functional activities. The replacement of D-56 in alpha-toxin resulted in complete loss of hemolytic, PLC, and SMase activities. The variant toxins at D-130 showed an approximately 100-fold reduction of biological activities compared to that of the wild-type toxin. The substitution of glutamine or glycine for E-152 caused complete loss of these activities, but substitution of aspartic acid for E-152 reduced but did not completely inhibit these activities. The variant toxins at D-56 and D-130, as well as the wild-type toxin, possessed approximately 2 mol of zinc atoms per mol of the protein, but E152G and E152Q contained approximately 1 mol of zinc metal per mol of the protein. On the other hand, the zinc content in E152D was calculated as about 1.4 mol in the toxin molecule. The replacement of D-56, D-130, or E-152 had no effect on binding to sheep erythrocytes and uptake of free zinc ion from the solution. The variant toxins at D-130 showed partial antigenic identity with the wild-type toxin on a double gel diffusion test. These observations suggest that D-56 in alpha-toxin is required for catalytic activity of alpha-toxin, D-130 is essential for maintenance of structure, and the carboxyl group of E-152 tightly ligands one zinc ion, which is essential for catalytic activity of the toxin. 相似文献
89.
Murata T Nakamura S Oka K Kawakami K Kato M Imai T Nakayama T Kuroda M Nakano H Watanabe M Shiraishi T 《Pathology international》2000,50(10):853-857
A case of primary gastric T-cell lymphoma, which was positive for granzyme B, is reported. The patient was a 47-year-old Japanese female who complained of a dull upper abdominal pain. Radiographic and endoscopic examinations revealed an ulcerative infiltrative lesion in her stomach. Following the confirmation of a high-grade malignant lymphoma, a distal gastrectomy with regional lymph nodal dissection was performed. The histology of the gastric lesion revealed a malignant lymphoma of the diffuse pleomorphic type without lymph nodal involvement. Immunohistochemistry revealed that the tumor cells were positive for LCA, CD3, TIA-1 and granzyme B, but were negative for CD4, CD8, CD56, CD30, L-26, EMA, TCR alpha/beta and TCR gamma/delta. Because the tumor cells showed T cell nature with cytotoxic activity proved by TIA-1 and granzyme B, and without evidence of further maturation of T cell, a malignant lymphoma originating from extrathymic-derived T cells was suggested. 相似文献
90.
Toshio Nishimura Keizo Tsuruhara Keiko Naito Junko Hirohara Sotokichi Morii 《Pathology international》1989,39(5):281-288
To examine the effect of colchicine on ethionine induced fatty liver, adult female rats were starved overnight and then injected i.p. with 1 g kg ethionine at 11th hour of fasting; then a half of the rats were also injected i.p. with 2.5 mg kg colchicine twice at 3 and 6 h after the single administration of ethionine. Similarly, fasted control rats were injected i.p. with vehicle alone at the above times. All of the rats were sacrificed after a 20 h fast, and the hepatocytes in periportal areas were observed ultra-structurally. In addition, total lipids in the liver tissue were extracted and determined biochemically. Although similar significant increases of triglyceride were observed in the liver tissue of all ethionine-injected rats, the hapatocytes in the group treated with both chemicals had fewer cytoplasmic fat globules (CFG) than those in the group treated with ethionine only. On the other hand, the diameters of markedly increased membrane-bound lipid particles (MLP) in the double treated group were distributed mainly in the range 0.2–0.4 μm, compared with those (0.1-0.2 μm) in the other groups. These findings indicate that colchicine inhibits the development of CFG in ethionine injured hapatocytes. Acta Pathol Jpn 39: 281∼288, 1989. 相似文献