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1.
Purpose: Mouse double-stranded DNA-dependent protein kinase (DNA-PK) activity is heat sensitive. Recovery of heat-inactivated DNA repair activity is a problem after combination therapy with radiation and heat. We investigated the mechanism of recovery of heat-inactivated DNA-PK activity.

Methods: Hybrid cells containing a fragment of human chromosome 8 in scid cells (RD13B2) were used. DNA-PK activity was measured by an in vitro assay. Immunoprecipitation of the nuclear extract was performed with an anti-Ku80 antibody. Proteins co-precipitated with Ku80 were separated by sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis and detected by Western blotting using anti-heat shock protein (HSP)72 and anti-heat shock cognate protein (HSC)73 antibodies. HSC73 was overexpressed with the pcDNA3.1 vector. Short hairpin (sh)RNA was used to downregulate HSC73 and HSP72.

Results: The activity of heat-inactivated DNA-PK recovered to about 50% of control during an additional incubation at 37?°C after heat treatment at 44?°C for 15?min in the presence of cycloheximide (which inhibits de novo protein synthesis). Maximal recovery was observed within 3?h of incubation at 37?°C after heat treatment. Constitutively expressed HSC73, which folds newly synthesized proteins, reached maximal levels 3?h after heat treatment using a co-immunoprecipitation assay with the Ku80 protein. Inhibiting HSC73, but not HSP72, expression with shRNA decreased the recovery of DNA-PK activity after heat treatment.

Conclusions: These results suggest that de novo protein synthesis is unnecessary for recovery of some heat-inactivated DNA-PK. Rather, it might be reactivated by the molecular chaperone activity of HSC73, but not HSP72.  相似文献   

2.
Clinical effect of LM-001, a prostaglandin synthetic inhibitor developed from a drug delivery system, was evaluated in 54 patients with pain from urinary tract stones (stone pain) and 32 with vesical urgency after an operation on bladder or prostate. LM-001, felbinac ethyl incorporated in lipid microsphere, wes intravenously administered at the onset of stone pain or vesical urgency. Of 54 with stones and 32 with urgency, 53 and 29 were eligible for response, respectively. The symptoms improved or disappeared in some cases just after the administration and in the majority of patients within 15 minutes, in 49 of 53 patients with stone pain. Further, the effectiveness lasted over 24 hours in 26 of the 49 responding to this agent. On one hand, improvement or disappearance of vesical urgency was recognized in 25 of 29 patients, and the effectiveness was observed shortly after injection in 16 and lasted over 24 hours in 13 cases. Toxicities of this drug were investigated in 54 patients with stone pain and 32 with urinary urgency. Side effects consisted of pain at the injection site in 4, a slight fall of blood pressure in 1, slight visual disturbance in 1, body heat sensation in 1, leukocytosis in 3 and elevation of alkaline phosphatase in 1. These symptoms were transient and disappeared without use of any agent. LM-001 is concluded to be a useful drug for controlling stone pain and vesical urgency since an immediate effect, long durability and high response rates were obtained without severe side  相似文献   
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We have experienced two patients of ischemic heart disease associated with renovascular hypertension. Patient 1 (60-year-old man) underwent LV aneurysmectomy and triple aortocoronary bypass grafting (saphenous vein to diagonal branch, left internal mammary artery to obtuse marginal branch, and right gastroepiploic artery to right coronary artery). Seventy five days after the initial cardiac surgery endarterectomy for the left renal artery and bifurcated Dacron graft implantation for the iliac artery obstruction were performed. Patient 2 (62-year-old woman) underwent simultaneous operation of both right nephrectomy and triple aortocoronary bypass grafting (saphenous vein grafts to obtuse marginal branch and right coronary artery, and left internal mammary artery to left anterior descending artery). Their postoperative courses were uneventful except unstable and high blood pressure for four to seven days after the operation. It appears that it should be decided to achieve either simultaneous or two stage approach for ischemic heart disease associated with renovascular hypertension based on the preoperative cardiac function. And both postoperative cardiac function and hypertension should be carefully managed until the blood pressure becomes stable after the surgery.  相似文献   
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The effect of dietary manipulation on global tooth uptake of 47Ca-chloride was evaluated in three rat models of metabolic bone diseases verified by histologic bone study. The 24-hr tooth uptake of 47Ca-chloride was significantly decreased in the osteomalacic group, and was increased in the osteoporotic group at the fourth week. Tooth uptake closely paralleled femoral uptake at a correlation coefficient of 0.73 (p less than 0.01). The uptake of 47Ca-chloride in tooth was found to be more affected by dietary manipulation than that in femur in our rat models.  相似文献   
7.
Patients with porcelain aorta carry a high risk of cerebral as well as systemic embolism during cardiac surgery. Here we describe a case of severe aortic stenosis and coronary artery disease combined with the circumferentially calcified aorta. The patient was a 77-year-old man who successfully received four coronary artery bypass grafts with in situ arterial grafts without clamping the aorta and aortic valve replacement. Aortic valve replacement and two distal coronary artery anastomoses to the left circumflex artery and obtuse marginal branch were performed under cardiac arrest during hypothermic perfusion with endoaortic balloon occlusion, followed by partial endarterectomy and closure of the aorta buttressed with bovine pericardium under deep hypothermic circulatory arrest. While rewarming, the other two distal coronary anastomoses to the left anterior descending artery and diagonal branch were done on the beating heart in order to minimize cardiac arrest time. On-pump beating heart coronary artery bypass grafting (CABG) can be useful especially for combined complex cardiac surgery.  相似文献   
8.
A statistic analysis was carried out on the 4,956 inpatients admitted to our Department of Urology from April 1972 to December 1991. The patients included 3,399 males and 1,557 females. A total of 4,105 operations including 255 renal allotransplantations were performed on 3,590 patients. Open surgery for upper urinary tract stones has been replaced by extracorporeal shock-wave lithotripsy (ESWL) in the last three years.  相似文献   
9.
Tissue distribution of epidermal growth-factor (EGF) in rat was investigated using a human EGF (hEGF) radioimmunoassay system. Antisera generated against hEGF reacted with hEGF and [21Leu] hEGF but not with mouse EGF, fibroblast growth factor (FGF), nerve growth factor (NGF), platelet derived growth factor (PDGF), and endothelial cell growth supplement (ECGS). Similar amounts of EGF immunoreactivity (EGF-IR) were found in the rat submandibular gland (32.8 +/- 4.59 ng/g tissue, n = 5) and duodenum (39.9 +/- 18.7 ng/g tissue, n = 9), whereas little EGF was detected in other tissues. No sex difference was observed in submandibular and duodenal EGF-IR, being different from the case of mouse in which ten times higher concentration of EGF-IR was found in male submandibular gland. Sephadex G-50 gel chromatography of submandibular and duodenal extracts revealed that each consisted of at least three different immunoreactive forms. The predominant EGF-IR was coeluted with 125I-EGF, significant amounts of EGF-IR was observed in the void volume fractions, and only small peaks of EGF-IR were present near Vt. These data clarified the presence of EGF-IR in rat submandibular and duodenal tissues and the molecular heterogeneity of EGF-IR and suggest some important role of EGF in the gastrointestinal function.  相似文献   
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