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91.
Tadashi Nomura MD ; Hiroto Terashi MD PhD ; Makoto Omori MD ; Atsushi Sakurai MD ; Takeru Sunagawa PhD ; Masumi Hasegawa MS ; Shinya Tahara MD PhD 《Wound repair and regeneration》2007,15(6):833-837
Hypertrophic scars (HS) are a consequence of abnormal wound healing. We examined fatty acids that are contained within, and participate in, every reaction through the membrane; then, we analyzed the percentage composition of the fatty acids in deepithelialized normal dermis (ND) and HS. In vivo HS samples were obtained from six patients undergoing surgical excision, and ND samples from five patients undergoing skin grafting surgery for excess. In vitro, cultured fibroblasts from HS and ND were also analyzed. The percentage composition of fatty acids extracted from all the samples was analyzed. In vivo, arachidonic acid (20:4) was significantly more abundant in HS than in ND, in the phospholipids from both whole tissue and cell membranes. In vitro, there were no significant differences among ND, HS, and 10% fetal calf serum. The results suggest that HS formation does not necessarily involve simple excess of 20:4; however, there are considerable differences in the percentage composition of 20:4 between ND and HS. Arachidonic acid probably participates in the formation and maintenance of HS, whereas in vitro cultured fibroblasts are affected largely by fetal calf serum. 相似文献
92.
Serial in vivo MR tracking of magnetically labeled neural spheres transplanted in chronic EAE mice. 总被引:5,自引:0,他引:5
Tamir Ben-Hur Ruud B van Heeswijk Ofira Einstein Michal Aharonowiz Rong Xue Emma E Frost Susumu Mori Benjamin E Reubinoff Jeff W M Bulte 《Magnetic resonance in medicine》2007,57(1):164-171
Neural stem cell (NSC) transplantation has been shown to attenuate the severity of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Central to the future success of NSC transplantation in MS is the ability of transplanted cells to migrate from the site of transplantation to relevant foci of disease. Using magnetically labeled mouse neurospheres and human embryonic stem cell (hESC)-derived neurospheres, we applied serial magnetic resonance imaging (MRI) to assess the biodynamics of transplanted cell migration in a chronic mouse EAE model. Magnetic labeling did not affect the in vitro and in vivo characteristics of cells as multipotential precursors. Cell migration occurred along white matter (WM) tracts (especially the corpus callosum (CC), fimbria, and internal capsule), predominantly early in the acute phase of disease, and in an asymmetric manner. The distance of cell migration correlated well with clinical severity of disease and the number of microglia in the WM tracts, supporting the notion that inflammatory signals promote transplanted cell migration. This study shows for the first time that hESC-derived neural precursors also respond to tissue signals in an MS model, similarly to rodent cells. The results are directly relevant for designing and optimizing cell therapies for MS, and achieving a better understanding of in vivo cell dynamics and cell-tissue interactions. 相似文献
93.
Hiroaki Shiba Takeyuki Misawa Susumu Kobayashi Tokuyasu Yokota Kyonsu Son Katsuhiko Yanaga 《Journal of gastrointestinal surgery》2007,11(4):549-551
A 41-year-old Chinese woman was admitted to our hospital with epigastric pain. Computed tomography detected a heterogeneous
enhancement tumor fed by the left gastroepiploic artery in the left lower quadrant and cholelithiasis. Excision of the tumor
in the greater omentum and cholecystectomy were performed laparoscopically. Histological findings confirmed a diagnosis of
hemangiopericytoma with low-grade malignancy. To our knowledge, hemangiopericytoma of the greater omentum is very rare, and
only 12 cases were reported in English literature. We report a case of hemangiopericytoma arising in the greater omentum and
review the literature. 相似文献
94.
In order to investigate the comparative fates of nivalenol (NIV) and 4-acetyl derivative of NIV (fusarenon-X, FX) in mice, 3H-FX or 3H-NIV was given p.o. to mice. Radioactivity was excreted mainly via the urine in mice given 3H-FX, but mainly via the feces in mice given 3H-NIV. The plasma radioactivity reached a peak at 30 or 60 min after the administration of 3H-FX or 3H-NIV, respectively. The plasma peak level was 5 times higher, and the area under curve (AUC) was 10 times higher, in 3H-FX-administered than 3H-NIV-administered mice. These findings clearly demonstrate that FX is absorbed from the gastrointestinal tract more rapidly and efficiently than NIV. The HPLC profile of radioactivity of acetonitrile extracts of urine and feces indicated that FX is rapidly metabolized to NIV after being absorbed from the gastrointestinal tract. In vitro incubation of tissue homogenates with 3H-FX demonstrated that the liver and kidney are the organs responsible for the FX-to-NIV conversion. Thus this study demonstrated that the higher oral toxicity of FX than NIV that has been observed in mice and rats is due to the efficient absorption of FX than NIV from the gastrointestinal tract, followed by its rapid conversion to NIV by the liver and kidney. 相似文献
95.
A multicolour tandem labelling fluorescence in situ hybridization(FISH) procedure was used to compare the frequencies of radiation-inducedchromosome breakage and hyperdiploidy of chromosome 1 occurringin non-cultured granulocytes and Go lymphocytes with those observedin cultured metaphase and interphase lymphocytes. Whole blood,obtained from healthy male donors, was exposed in vitro to 0,100, 200, 300 and 400 cGy of ionizing radiation from a 137Cssource. Aliquots containing granulocytes and Go lymphocytesfrom each dose were treated immediately with hypotonic KCl onice and harvested. Cells were hybridized with 相似文献
96.
We determined the serum levels of the creatine kinase B subunit (CK-B) by an enzyme immunoassay method in patients with renal cell carcinoma (RCC) and benign renal diseases. Eighteen of 76 patients with RCC (24%) had elevated serum CK-B levels. The positive rates were 29% in stage I, 13% in stage II, 15% in stage III, and 27% in stage IV. In all 9 patients whose serum CK-B levels were serially measured and had been elevated before operation, the CK-B levels were reduced to the normal range after nephrectomy. These findings indicate that serum CK-B is a useful biomarker for monitoring the clinical course for a limited number of RCC patients, but is not a marker for diagnosis and staging. Concentrations of CK-B in RCC tissues were significantly lower than those of normal kidney. A high rate of cell turnover in tumor tissues might entail the higher level of serum CK-B in patients with RCC. 相似文献
97.
Yoshimi Otani Ichiro Yoshida Satoshi Ohki Motoi Kano Osamu Kawashima Masao Suzuki Yasushi Sato Toru Takahashi Akio Ohtaki Susumu Ishikawa Yasuo Morishita 《Surgery today》1997,27(9):812-815
Pulmonary aspergillosis associated with old tuberculosis is generally resistant to treatment. Thus, if patients are treated
only with conservative therapy, their condition continues to deteriorate due to repetitive hemoptysis, and may even become
critical. Surgical treatment is required for these patients; however, it is extremely difficult to resect the lesion due to
severe adhesions to the chest wall and vascular proliferation surrounding the lesion. We performed preoperative arterial embolization,
achieving good results in three patients with hemoptysis caused by pulmonary aspergillosis. The feeding arteries were embolized
using microcoils and/or gelatin sponges, and a lobectomy was safely carried out in all patients. We concluded that preoperative
arterial embolization is a safe and effective technique to prevent massive hemorrhage occurring at the time of surgery.
This work was presented at the 11th Annual Meeting of the Japanese Association for Chest Surgery, held in Kyoto, Japan, May
13–14, 1994 相似文献
98.
99.
A gene encoding sannamycin B-glycyltransferase (sms13) of Streptomyces sannanensis IFO 14239 was identified by cloning and complementation of S. sannanensis mutant SN13 which is blocked at the interconversion of sannamycins B and A. The cloned DNA fragment also permitted the conversion of fortimicin B to A both in S. sannanensis SN13 and Streptomyces lividans TK23. DNA sequences similar to sms13 were detected in all five producers of the fortimicin-group antibiotics, Micromonospora olivasterospora ATCC 21819 (fortimicin-producer), Micromonospora sp. strain SF-2098 ATCC 31580 (SF-2052), Dactylosporangium matsuzakiense ATCC 31570 (dactimicin), Streptomyces tenjimariensis ATCC 31603 (istamycin), and Saccharopolyspora hirsuta ATCC 20501 (sporaricin). This suggests that these genes of similar function from different genera were derived from a common ancestral gene. 相似文献
100.
Toshimichi Hasegawa Yuko Tazuke Yasuhiro Iwasaki Osamu Monta Junichi Sumimura Hiroshi Koyama Toru Dezawa 《Surgery today》1997,27(12):1191-1194
We report herein the case of a premature infant with esophageal atresia (EA) and a tracheoesophageal fistula (TEF) associated
with cardiac anomalies who was successfully treated by an early ligation of the TEF following gastrostomy, and delayed repair
of the esophagus. A 1212-g male was born prematurely at 31 gestational weeks, at which time he was diagnosed as having EA
with TEF and patent ductus arteriosus (PDA), ventricular septal defect (VSD), and atrial septal defect (ASD). A gastrostomy
was initially performed but following extubation he gradually became tachypneic. A chest roentogenogram revealed atelectasis
and ground-glass appearance, and reintubation was required. Ligation of the TEF was performed 53h after his birth. Following
the improvement of his respiratory condition through ventilatory support and the intratracheal administration of pulmonary
surfactant, he underwent repair of the esophagus on the 6th day of life. Postoperatively, he suffered from heart failure,
but was treated with peritoneal dialysis and pharmacological closure of the PDA. Weaning the infant from the ventilator proved
difficult, but it was finally achieved when he had reached a weight of 2268g at 3 months of age by enteral feeding. Our experience
of this case demonstrates that early ligation of TEF should be performed for a premature infant with EA and TEF before respiratory
distress syndrome (RDS) has developed. If a gastrostomy is required to prevent gastric distention, it should be followed by
simultaneous or immediate ligation of the TEF. 相似文献