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1.
Mitogenic and protein synthetic activity of tissue repair cells: control by the postsurgical macrophage 总被引:3,自引:0,他引:3
M Fukasawa J D Campeau D L Yanagihara K E Rodgers G S Dizerega 《Journal of investigative surgery》1989,2(2):169-180
It is well known that fibroblasts are a main source of extracellular matrix synthesis necessary for tissue repair. In addition, macrophages secrete products that are known to modulate synthesis of extracellular matrix. Accordingly, we studied the incorporation of [3H]thymidine, [3H]proline, and [35S]sulfate into macromolecules produced by fibroblasts recovered from the site of peritoneal tissue repair cultured with and without spent media from postsurgical peritoneal macrophages. Rabbits underwent resection and reanastomosis of their small intestines. Peritoneal exudative cells (PEC) were then collected on postsurgical day 5 and day 10 as well as from nonsurgical controls, separated by discontinuous Percoll gradient centrifugation, and cultured for 48 h. A second group of rabbits underwent peritoneal wall abrasion from which fibroblast tissue repair cells (TRC) were collected from the site of injury at postsurgical day 7 and maintained in culture for varying times. Incorporation of radiolabeled precursors into DNA, collagen, and sulfated proteoglycans was determined. Incorporation of [3H]thymidine and [3H]proline into untreated TRC gradually decreased with culture duration. Conversely, [35S]sulfate incorporation gradually increased during prolonged culture. Macrophage spent media increased the levels of [3H]thymidine incorporation by the TRC. [3H]Proline and [35S]sulfate incorporation into TRC were also stimulated by macrophage spent media. However, this stimulation may be due to the enhanced proliferation of TRC by macrophage spent media. In conclusion, tissue repair fibroblasts are activated for postsurgical repair at the site of injury by many factors including secretory products from postsurgical macrophages. 相似文献
2.
L Sumitra Hada Nobuko Kakiuchi Masao Hattori Tsuneo Namba 《Phytotherapy research : PTR》1989,3(4):140-144
During the course of our studies on dental caries prevention by traditional medicines, fatty acids (myristic and oleic acids etc.) and procyanidins from betel nuts (the seed of Areca catechu L.) were respectively revealed to be the major antibacterial principles against a primary cariogenic bacterium, Streptococcus mutans, and the major inhibitory principles against glucosyltransferase from S. mutans. 相似文献
3.
The purpose of this study was to determine the effect of pulsatile flow on cerebral perfusion under cardiopulmonary bypass (CPB). Twenty-three patients who underwent cardiac operations were divided into two comparable groups: Group A (N = 11) had standard nonpulsatile flow, while in Group B (N = 12), a pulsatile pump was used. The blood flow of left common carotid artery and radial arterial pressure were continuously monitored during cardiac operation in both groups and cerebral vascular resistance was calculated. In Group B, the perfusion pressure of left common carotid artery was monitored and compared with that of radial artery. Arterial and internal jugular venous blood were sampled and the difference of cerebral A.V O2 contents and cerebral oxygen consumption was calculated. Cerebral vascular resistance in Group B (54.0 +/- 11.2% of the value of before-CPB) significantly decreased compared to that in Group A (72.2 +/- 11%) at the end of CPB (p less than 0.05). Pulse pressure following pulsatile CPB flow was 15.1 +/- 5.8 mmHg monitored in radial artery and it reduced to 8.5 +/- 5 mmHg in left common carotid artery. Although there was no significant difference in cerebral oxygen consumption of both groups during and just after CPB, the difference of cerebral A-V O2 contents of Group B was greater than Group A just after CPB. These data suggest that pulsatile flow may minimize the cerebral microcirculatory shunt during CPB, resulting from the reduction of cerebral vascular resistance. 相似文献
4.
5.
T Shimanuki H Orita M Fukasawa C Nakamura M Kobayashi M Washio 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1990,38(2):324-329
Four patients with viscero-atrial heterotaxic syndrome underwent a right heart bypass operation. 2 patients had right isomerism, and two had left isomerism. 3 patients had common atrio-ventricular canal, three had double outlet right ventricle, one had mitral valve hypoplasia, and one had double inlet right ventricle. All patients had anomalous systemic or pulmonary venous drainage. Redirection of systemic venous drainage was accomplished by total cavo-pulmonary shunt (TCPS) (2 patients), atrial baffle (1 patient), and intraatrial conduit (1 patient). In one patient underwent TCPS, regurgitant common atrioventricular valve was replaced with a prosthetic valve. One who had total anomalous pulmonary venous drainage (type Ib) died after cardiac repair. The three survivors are in improved condition. The right heart bypass operation, like total cavopulmonary shunt or connection, simplifies the redirection of systemic venous drainage and offers improved results in the surgical treatment of complex cardiovascular anomalies with viscero-atrial heterotaxic syndrome. 相似文献
6.
A series of 1 beta-methylcarbapenem compounds, which have a 5'-substituted-N-methylpyrrolidin-3'-ylthio group as a C-2 side chain, have been prepared and their biological properties were investigated. Substitution with a methyl group on the nitrogen atom in the C-2 side chain effectively enhanced stability to renal dehydropeptidase-I as well as introduction of methylene spacer between the aminocarbonyl group and the pyrrolidine ring of the 5'-aminocarbonylpyrrolidin-3'-ylthio group. 相似文献
7.
Nobuko Shiraiwa Toshihiro Yoshizawa Norio Ohkoshi Akira Tamaoka 《Clinical neurology》2007,47(4):169-172
A 17-year-old boy with high fever, headache, and neck stiffness was admitted to our hospital. Spinal fluid showed a protein level of 215 mg/dL with myelin basic protein (579 pg/mL), 347/ microl cells (330 mononuclear cells), and a glucose level of 53 mg/dL. One week later, urinary retention, flaccid paraplegia, and sensory disturbance below the 10th thoracic level developed. MRI of the spinal cord revealed swelling and T2-high intensity area in the cord at the 11th and 12th thoracic level. Although high-dose of methylprednisolone was administered, consciousness disturbance and respiratory failure that required mechanical ventilation occurred. Bilateral abducens nerve palsy, nystagmus, and flaccid tetraparesis also occurred. Brain MRI revealed T2-high intensity area in the midbrain and pons. Nerve conduction study showed diminished amplitudes and prolonged latencies or absence of F waves. The patient was administered a combination of intravenous immunoglobulin and a high-dose of methylprednisolone. He showed improvement within one week after the treatment. Two weeks later, he recovered from respiratory failure and weakness of the upper limbs. He remained paraplegic, but gradually improved and was able to walk with support one and a half years later. We suggest the combination therapy of intravenous immunoglobulin and a high-dose of methylprednisolone is effective for patients with combined ADEM and peripheral neuropathy. 相似文献
8.
Norio Ohkoshi Hldehlro Mizusawa Nobuko Shiraiwa Shin'Ichi Shoji Katsutoshi Harada Kazuo Yoshizawa 《Muscle & nerve》1995,18(11):1265-1271
Lmmunohistochemical analyses were made of the superoxide dismutases (Mn-SOD and CuiZn-SOD) in biopsied muscles from 7 patients with mitochondrial encephalomyopathies that included mitochondrial encephalomyopathy, lactic acidosis and strokelike episodes (MELAS), and chronic progressive external ophthalmoplegia (CPEO). Mn-SOD mainly was present in the subsarcolemmal region, but it also was found in a coarsely granular, reticular, or diffuse pattern of staining within the muscle fibers. These Mn-SOD-positive fibers corresponded almost completely to the ragged-red fibers. The immunoreaction for CuiZn-SOD was weakly positive in some of the muscle fibers positive for Mn-SOD. In CPEO, Mn-SOD-positive fibers predominantly showed decreased cytochrome c oxidase (COX) activity. In MELAS, Mn-SOD-positive fibers tended to be stained deeply for COX although a few were COX-negative. These findings suggest that Mn-SOD-positive fibers can be used to make a differential diagnosis between CPEO and MELAS and that in mitochondrial encephalomyopathies Mn-SOD in the raggedred fibers may protect against oxidative stress. © John Wiley & Sons, Inc. 相似文献
9.
Tadao Fukushima Yoji Nagashima Yukio Nakatani Nobuko Nakarnura Kiyoshi Fukasawa Yoshiaki Satomi Ken Yu Yohei Miyagi Ichiro Aoki Kazuaki Misugi 《Pathology international》1994,44(5):401-406
Chromophobe renal cell carcinoma (RCC) is a recently established subtype of RCC, which has rarely been reported in Japan. In this communication, the authors report two Japanese cases of chromophobe RCC together with the immunohistochemical findings. The tumors were composed of sheets and cribriform glands formed by tumor cells with cloudy and reticular cytoplasm. Ultrastructurally, the cytoplasm was filled with numerous microvesicles. The tumor cells were positive for cytokeratin, epithelial membrane antigen, and Tamm-Horsfall protein. Occasionally, LeuM1-positive cells were also noted. Vimentin was negative, unlike the usual RCC. Reactivity for peanut agglutinin was more frequent than that to Lotus tetragonolobus agglutinin. The results of this study suggest that the tumor cellq possessed phenotypes similar to the distal nephron rather than to the proximal tubular cells. 相似文献
10.
Massive apoptosis in infantile myofibromatosis. A putative mechanism of tumor regression. 总被引:4,自引:3,他引:4 下载免费PDF全文
Y. Fukasawa H. Ishikura A. Takada S. Yokoyama M. Imamura T. Yoshiki H. Sato 《The American journal of pathology》1994,144(3):480-485
Two cases of solitary infantile myofibromatosis (IM) are presented. Solitary IM are tumors prone to spontaneous regression. Histopathologically, several tumor lobules in our IM cases had central areas of massive cell death, with nuclear pyknosis, cytoplasmic hyalinization and nuclear fragmentation but without lymphoid or neutrophilic cell infiltration. These central cell death areas consisted of about 40% in case 2 and 50% in case 1 of the entire tumor tissues, respectively. Electron microscopy revealed that the condensed nuclei and cytoplasm were fragmented into "apoptotic bodies", with or without phagocytosis by histiocytes. DNA fragmentation, as evidenced by the terminal deoxy transferase-mediated uptake of biotinylated dUTP, was identified at massive cell death areas on paraffin sections from both cases. A characteristic 180- to 190-bp nucleosomal ladder was detected in DNA obtained from the tumor cells in case 1. The collective evidence suggested that these tumors underwent a central, massive apoptosis. As massive cell death similar to that seen in the present cases has been described in other documented cases of IM, we propose that the spontaneous regression that frequently occurs with this type of tumor may be mediated by massive apoptotic cell death. 相似文献