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81.
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
82.
J Tamaru A Mikata H Horie K Itoh T Asai R Hondo S Mori 《The American journal of surgical pathology》1990,14(6):571-577
We report two cases of herpes simplex lymphadenitis without widespread organ involvement in a 60-year-old man and a 67-year-old woman. Their complaints were high fever and generalized erythema followed after few days by generalized lymphadenopathy. This report describes the findings obtained by light and electron microscopy, immunohistochemistry, and in situ hybridization. In both instances, Cowdry's type A intranuclear inclusion bodies were found in T-immunoblasts in the background of T-zone hyperplasia with focal necrosis. Electron microscopic investigation revealed intranuclear and cytoplasmic virus particles with characteristics of the herpes group. Immunohistochemical staining utilizing anti-herpes simplex virus (HSV) antibody was positive and in situ hybridization with HSV-DNA probe revealed positive signals in the nucleus and in the cytoplasm of T-immunoblasts. Although rare, HSV lymphadenitis in the absence of generalized infection can occur. 相似文献
83.
M Kojima Y Hosomura H Itoh T Johshita Y Ohno K Yoshida S Asano H Wakasa S Nakamura T Suchi 《Acta pathologica japonica》1991,41(5):363-368
In order to clarify the appearance of monocytoid B lymphocytes (MBLs) in abscess-forming granulomatous lymphadenitis (AGL) and the relation between AGL and cat-scratch disease (CSD), 48 cases of AGL were studied histologically. MBLs were present in about 50% of AGL cases. Warthin-Starry (WS) silver stain-positive bacteria, which are the causative agent of CSD, were present in 52.4% of AGL cases with MBLs and 59.2% of AGL cases without MBLs. The appearance of MBLs in AGL was not related to various clinical features, including disease interval from initial lymphadenopathy to lymph node biopsy. Histologically, epithelioid cell clusters appeared in about 70% of MBL-positive AGL cases, but were not observed in MBL-negative AGL. Therefore, a close interaction between MBLs and epithelioid cells in AGL is suggested, and we emphasize that the histological features of some AGL cases resemble those of toxoplasmic lymphadenitis. 相似文献
84.
Yuichi Ando Kenji Kikuchi Naoya Ichikawa Kazuhiko Meigata Yuji Nomura Kenshi Watanabe Yoshifumi Beck Hisakazu Degawa Shinji Tomikawa Takeshi Nagao Hisanori Chida 《Surgery today》1997,27(4):353-356
We herein report the case of a 53-year-old man with a nonspecific acute colonic ulcer whose liver function deteriorated after he had undergone hepatectomy. He was referred to our hospital for a hepatoma caused by hepatitis B virus and a right hemihepatectomy was performed. His liver function was poor after the operation, and minor complications such as pleural effusion and biliary fistula developed. A large amount of melena was seen 29 days after the hepatectomy and he developed hemorrhagic shock. Superior mesenteric arteriography revealed pooling of blood in both the hepatic flexure of the ascending colon and the cecum. An emergency right hemicolectomy was performed. There was a 5 x 1-mm ulcer 18 cm distal to the ileocecal valve. Numerous erosions were observed to be scattered throughout the colonic mucosa. The patient recovered slowly and was discharged 6 months after the hepatectomy. This is the first report of an acute colonic ulcer that could have been caused by liver dysfunction. 相似文献
85.
86.
H Iioka I Moriyama K Itoh K Hino Y Okamura Y Itani Y Katoh M Ichijo 《Nippon Sanka Fujinka Gakkai zasshi》1987,39(12):2133-2136
To elucidate the role of glutathione (GSH) on placental amino acid transport, we investigated L-lysine transport using microvillous membrane vesicles prepared from full term human placenta. 1. The transport of L-lysine into microvillous membrane vesicles was not affected by glutathione. 2. The transport of L-lysine into microvillous membrane vesicles was inhibited by inorganic mercury (Hg2+), and 0.1mM Hg2+ inhibited 34% of this transport and 1mM Hg2+ inhibited 50%. 3. The transport of L-lysine inhibited by Hg2+ was almost completely restored when glutathione was added simultaneously. These results indicated that glutathione defended the inhibitory action of inorganic mercury on L-lysine transport across microvillous membrane. 相似文献
87.
Clinical effects of percutaneous cardiopulmonary support in severe heart failure: early results and analysis of complications. 总被引:2,自引:0,他引:2
Shigeru Sakamoto Junichi Matsubara Toshiaki Matsubara Yasuhiro Nagayoshi Shinji Shono Hisateru Nishizawa Masaaki Kanno Katsunori Takeuchi Toshimichi Nonaka Jun Kyosawa 《Annals of thoracic and cardiovascular surgery》2003,9(2):105-110
Between January 1993 and December 2001, we employed percutaneous cardiopulmonary support (PCPS) in 35 patients. PCPS was used for postcardiotomy in 25 of these patients who could not be weaned from cardiopulmonary bypass (CPB) because of severe cardiogenic shock. In the other 10 patients, PCPS was used for a non-surgical disease. Twenty-nine patients (82.9%) were weaned from PCPS, and 28 (80.0%) survived. The other 7 patients (20.0%) died due to postoperative complications. The causes of death were multiple organ failure (MOF) due to wound bleeding, low cardiac output syndrome (LOS), myonephropathic metabolic syndrome (MNMS) with severe lower limbs ischemia, cerebrovascular accident (CVA), and sepsis. The first cause for the complications was postoperative sustained severe heart failure. To improve the survival rate, it was necessary to prevent bleeding and begin PCPS at an earlier stage. 相似文献
88.
Hollow microspheres for use as a floating controlled drug delivery system in the stomach. 总被引:6,自引:0,他引:6
Hollow microspheres (microballoons), loaded with drug in their outer polymer shells, were prepared by a novel emulsion-solvent diffusion method. The ethanol:dichloromethane solution of drug (tranilast or ibuprofen) and an enteric acrylic polymer were poured into an agitated aqueous solution of polyvinyl alcohol that was thermally controlled at 40 degrees C. The gas phase generated in the dispersed polymer droplet by the evaporation of dichloromethane formed an internal cavity in the microsphere of the polymer with the drug. The drugs incorporated in the solidified shell of the polymer were found to be partially or completely amorphous. The flowability and packability of the resultant microballoons were much improved compared with the raw crystals of drug. The microballoons floated continuously over the surface of acidic dissolution media containing surfactant for greater than 12 h in vitro. The drug release behavior of the microballoons was characterized as an enteric property, and drug release rates were drastically reduced depending on the polymer concentration at pH 6.8. 相似文献
89.
Effect of KC399, a newly synthesized K+ channel opener, on acetylcholine-induced electrical and mechanical activities in rabbit tracheal smooth muscle.
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K. Kamei H. Nabata H. Kuriyama Y. Watanabe T. Itoh 《British journal of pharmacology》1995,115(8):1493-1501
1. Effects of KC399, an opener of ATP-sensitive K+ channels were investigated on membrane potential, isometric force and intracellular Ca2+ ([Ca2+]i) mobilization induced by acetylcholine (ACh) in smooth muscle from the rabbit trachea. 2. In these smooth muscle cells, ACh (0.1 and 1 microM) depolarized the membrane in a concentration-dependent manner, KC399 (1-100 nM) hyperpolarized the membrane whether in the presence or absence of ACh. When the concentration of ACh was increased, the absolute values of the membrane potential induced by the maximum concentration of KC399 were less negative. 3. ACh (0.1 to 10 microM) concentration-dependently produced a phasic, followed by a tonic increase in both [Ca2+]i and force. KC399 (above 3 nM) lowered the resting [Ca2+]i and attenuated the ACh-induced phasic and tonic increases in [Ca2+]i and force, in a concentration-dependent manner. The magnitude of the inhibition was greater for the ACh-induced tonic responses than for the phasic ones. Nicardipine (0.3 microM), a blocker of the L-type Ca2+ channel, attenuated the ACh-induced tonic, but not phasic, increases in [Ca2+]i and force. KC399 further attenuated the ACh-induced tonic responses in the presence of nicardipine. 4. In beta-escin-skinned strips, Ca2+ (0.3-10 microM) produced a contraction in a concentration-dependent manner. KC399 (0.1 microM) had no effect on the Ca(2+)-force relationship in the presence or absence of ATP with GTP. However, at a very high concentration (1 microM), this agent slightly shifted the relationship to the right and attenuated the maximum Ca(2+)-induced contraction.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
90.
Akira Sezai Motomi Shiono Tatsuya Inoue Mitsumasa Hata Mitsuru Iida Tetsuya Niino Akira Saito Tsutomu Hattori Shinji Wakui Masao Soeda Nanao Negishi Yukiyasu Sezai 《Annals of thoracic and cardiovascular surgery》2004,10(3):191-194
The patient was a 48-year-old male who was diagnosed with unstable angina. He had worsening cardiogenic shock during coronary angiography. Emergency coronary artery bypass grafting (CABG) was performed. He had a methicillin-resistant Staphylococcus aureus (MRSA) mediastinitis on day 22 after CABG. Drains were placed in the anterior mediastinum, left thoracic cavity, and abscess cavity, and another drain was placed in the mediastinal space for continuous cleansing with povidone iodine, oxydol. For antibiotics, teicoplanin (TEIC) was administered intravenously and to the local site via the cleansing drain for about one month. No MRSA was detected by culture in discharges from the mediastinal drain. Inflammatory findings were improved, and the patient was discharged and resumed everyday life without recurrence of inflammation as of eight months. Although the number of cases of MRSA mediastinitis is small and accumulation of cases is necessary to investigate therapeutic methods and selection of antibiotics, our department will select closed continuous cleansing and TEIC for antibiotics as the first choice for MRSA mediastinitis, and accumulate cases to investigate its efficacy. 相似文献