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61.
Toshiharu Mori Nobukazu Okimoto Akinori Sakai Yuichi Okazaki Nariaki Nakura Takuya Notomi Toshitaka Nakamura 《Journal of bone and mineral research》2003,18(11):2002-2009
To investigate the relationship between the effects of bone turnover and bone marrow cell development in bone cells, we developed a mouse voluntary climbing exercise model. Climbing exercise increased bone volume and transient osteogenic potential of bone marrow. This model would be suitable for investigating the mechanistic roles of mechanical loading. INTRODUCTION: The relationship between bone mass gain and local bone formation and resorption in mechanically loaded bone is not well understood. MATERIALS AND METHODS: Sixty-five C57BL/6J mice, 8 weeks of age, were assigned to five groups: a baseline control and two groups each of ground control and climbing exercise mice for 2 and 4 weeks. Mice were housed in a 100-cm tower and had to climb toward a bottle placed at the top to drink water. RESULTS: Compared with the ground control, bone mineral density of the left femur increased in the climbing mice at 4 weeks. At 2 and 4 weeks, bone formation rate (BFR/BS) of periosteal surface, the cross-sectional area, and moment of inertia were increased in the climbing mice, whereas BFR/BS and eroded surface (ES/BS) of endosteal surface did not differ. The trabecular bone volume (BV/TV) of the proximal tibia increased in climbing mice, and osteoclast surface (Oc.S/BS) and osteoclast number decreased at 2 weeks. At 4 weeks, there were increases in BV/TV and parameters of bone formation, including mineralized surface, mineral apposition rate, and bone formation rate. In marrow cell cultures from the tibia, the number of alkaline phosphatase+ colony forming units-fibroblastic and the area of mineralized nodule formation in climbing mice were increased, and the number of osteoclast-like TRACP+ multinucleated cells was lower at 2 weeks. At 4 weeks, these parameters recovered to the levels of the ground controls. CONCLUSION: Our results indicate that climbing increased trabecular bone volume and reduced bone resorption, with a subsequent increase in bone formation. Intermittent climbing downregulates marrow osteoclastogenic cells and upregulates osteogenic cells initially, but further exercise seemed to desensitize them. Cortical envelopes were enlarged earlier, but the response seems to differ from trabecular bone. 相似文献
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Hiroshi Yano Masahiro Murakami Yoshiaki Nakano Takeshi Tono Tadashi Ohnishi Takashi Iwazawa Yutaka Kimura Toshiyuki Kanoh Takushi Monden 《Digestive endoscopy》2004,16(4):343-346
We performed laparoscopic appendectomy and drainage to treat panperitonitis due to perforated appendicitis that occurred in a 28‐year‐old woman. We believe this is an appropriate procedure to treat perforated appendicitis because it is safe and minimally invasive, and faster recovery can be expected than after conventional open appendectomy. 相似文献
66.
Y Terao I Kuwajima Y Suzuki S Ueda M Sakai S Ohkawa S Matsushita K Kuramoto 《Nihon Ronen Igakkai zasshi. Japanese journal of geriatrics》1992,29(6):498-502
The clinical features of congestive heart failure in the elderly were investigated in 104 patients (57 males, 47 females, mean age of 79.2). Patients were divided into two subgroups, the readmission group, 33 patients who were readmitted within 6 months after discharge, and the non-readmission group. Chief complaints were dyspnea, edema, chest pain, loss of appetite, chest compression, and palpitation. Heart failure was caused by infection, myocardial ischemia, arrhythmia, inappropriate drug usage including poor drug compliance, the use of beta-blockers, excessive intake of sodium, and anemia. Careful use of drug was essential especially in the readmission group. Major underlying heart disease were ischemic heart disease (39.4%), valvular disease (26.9%), hypertensive heart disease (9.6%), with cardiomyopathy, congenital heart disease seen in the minority. There was no statistically significant difference in underlying heart diseases between the two groups. Supraventricular arrhythmias such as atrial fibrillations, paroxysmal atrial fibrillations, paroxysmal supraventricular tachycardias, and premature atrial contractions were noted in 85.3% of the cases. Drugs for treatment were diuretics, digitalis, isosorbide dinitrate, calcium antagonists. ACE inhibitors and alpha-blockers were also used, showing that vasodilators were more extensively used than before. The major complications were hypertension (39.4%), renal dysfunction (27.9%), cerebrovascular disease (26.9%), diabetes mellitus (16.5%), arteriosclerosis obliterans (7.7%). Renal dysfunction, arteriosclerosis obliterans was seen significantly more frequently in the readmission group. The prognosis at one year after admission was significantly worse in the readmission group. In summary, the major underlying diseases were ischemic heart disease, valvular disease, and hypertensive heart disease. Ischemic heart disease was seen more frequently than in previous investigations at our hospital.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
67.
Multiple intracerebral hemorrhages due to cerebral amyloid angiopathy after head trauma 总被引:1,自引:0,他引:1
K Wakui K Seguchi T Kuroyanagi T Sakai Y Tanaka Y Kamijoh Z Shiozawa 《No shinkei geka. Neurological surgery》1988,16(11):1287-1291
Cerebral amyloid angiopathy (CAA) is an important cause of intracerebral hemorrhage and ischemic cerebrovascular disease in some normotensive elderly patients. The diagnosis is made by proof of amyloid deposition in the vessel wall. A case of recurrent and multiple intracerebral hemorrhages due to cerebral amyloid angiopathy after head injury is reported. A 74-year-old female was referred to our hospital because of head injury. CT scan showed traumatic subarachnoid hemorrhage and intraventricular hematoma. Her consciousness was clear but slight disorientation was recognized. Conservative therapy was performed. During the course subcortical hemorrhages occurred five times and during the second one, right frontal and right parietal hemorrhages occurred simultaneously. Her consciousness deteriorated. The second subcortical hemorrhage was especially complicated by a ventriculoperitoneal shunt operation. A biopsy of the cortex was performed and pathological examination revealed amyloid deposition in the walls of small pial and cortical vessels. Occasional duplicated wall, obliterative intimal proliferation and disappearance of elastic lamina were recognized. The patient sank into a vegetative state due to recurrent and multiple hemorrhages. CAA results in two possibilities, hemorrhage and ischemic cerebrovascular disease. When lobar or subcortical hemorrhage is encountered in a normotensive elderly patient, the possibility of a CAA-related hemorrhage should be considered. The author carefully emphasizes that there is indication for neurosurgical treatment in CAA patients and proposes that therapy for ischemic cerebrovascular disease should be given special attention. 相似文献
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69.
Masaaki Kohta Hiroaki Minami Kazuhiro Tanaka Keiichi Kuwamura Takeshi Kondoh Eiji Kohmura 《Journal of clinical neuroscience》2007,14(2):167-170
A 52-year-old man fell from standing and a computed tomography (CT) scan revealed traumatic intracerebral haematoma and subarachnoid haemorrhage in the temporal cortex. He was treated without surgery and discharged. On day 30 after the accident, he had no neurological deficit. On day 37 he complained of headache and urinary incontinence, and on day 39 he was hospitalized due to progressive neurological deterioration (reduced conciousness, dilated pupils, and left hemiplegia). A CT scan revealed a diffuse low-density in the right cerebral hemisphere with marked midline shift. Emergency decompressive craniectomy and right temporal lobectomy were performed. Angiography after surgery revealed moderate vasospasm in the right middle and anterior cerebral arteries. The patient remained severely disabled. Delayed onset neurological deterioration can be caused by brain oedema and vasospasm after traumatic brain injury, despite an intervening period of improvement. 相似文献
70.
Endogenous bone-marrow-derived stem cells contribute only a small proportion of regenerated myocardium in the acute infarction model. 总被引:6,自引:0,他引:6
Shinya Fukuhara Shinji Tomita Takeshi Nakatani Chikao Yutani Soichiro Kitamura 《The Journal of heart and lung transplantation》2005,24(1):67-72
BACKGROUND: Our recent study showed that granulocyte-colony stimulating factor (G-CSF) promoted bone-marrow cells (BMC) to migrate into the infarcted heart and that they differentiated into cardiomyocytes. However, we still do not know to what degree bone-marrow-derived cardiomyocytes contribute to myocardial regeneration after injury. In this study, we verified the proportional contribution of cells from bone marrow (BM) and from non-bone marrow (n-BM) in regenerating neomyocardium after myocardial infarction. METHODS: Eight C57BL/6 mice were irradiated (900 cGy), and green fluorescent protein (GFP) mouse-derived BMCs (GFP-BMC, 1 x 10(6) cells) were injected. Four weeks later, the left descending coronary artery was ligated. Recombinant human G-CSF (200 microg/kg/day, 8 days) was injected. At 4 weeks after ligation, hearts were fixed for histology. We calculated the proportions of cardiomyocytes derived from BM and n-BM after taking the chimeric rate into consideration. RESULTS: The chimeric rate was 54.6% +/- 5.9%. At the infarcted border area, the total cell number was 1000.3 +/- 56.5/mm(2), and mobilized BM-derived GFP-BMC was 103.3 +/- 13.1/mm(2). After compensation with the chimeric rate, we found BM-derived troponin I-positive cells at 23.9 +/- 4.1/mm(2), nestin-positive cells at 12.9 +/- 2.6/mm(2), and Ki67-positive cells at 18.3 +/- 2.6/mm(2), respectively. We found significant differences in the contribution of troponin I-(6.7% +/- 1.7% vs 93.3% +/- 1.7%), nestin- (2.4 +/- 0.5 vs 97.6 +/- 0.5), and Ki67-positive (3.9 +/- 1.0 vs 96.1 +/- 1.0) cells derived from BM and n-BM. CONCLUSIONS: Bone marrow was one of the origins of regenerated cardiomyocytes; however, the contribution of cells from BM was very small compared with those of n-BM origin in the infarction model. 相似文献