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171.
T Usuba Y Ishibashi Y Okawa T Hirakawa K Takada K Ohkawa 《International journal of cancer. Journal international du cancer》2001,94(5):662-668
Ubiquitin-conjugated proteins in human colorectal cancer tissues were analyzed by the immunoprecipitation with the antibody FK2 against conjugated ubiquitin followed with SDS-PAGE. In these immunoprecipitable proteins, a 38-kDa protein was abundant in the tumor regions but almost absent in the adjacent normal regions in 17/26 patients, thus we attempted to purify it. Using immunoaffinity chromatography with the antibody FK2 followed by gel filtration and SDS-PAGE, approximately 10 pmol of this protein was separated from 34 g of the pooled cancerous tissue and transferred onto a PVDF membrane. The 38-kDa protein was further digested with Achromobacter protease I, resulting in several peptide fragments. Amino acid sequences of these peptides showed complete sequence identity to those derived from either ubiquitin or phosphoglycerate mutase-B, suggesting that the 38-kDa protein is monoubiquitinated phosphoglycerate mutase-B, whose calculated mass is 37,369 Da. Western blot using an antibody against phosphoglycerate mutase-B revealed the presence of the 38-kDa protein in the anti-ubiquitin immunoprecipitates derived from the tumor regions, but not from normal counterparts. In addition, part of non-ubiquitinated phosphoglycerate mutase-B (29 kDa) was also found in the anti-ubiquitin immunoprecipitates, whose levels were higher in the tumor regions than in the adjacent normal regions. These results suggest that monoubiquitination of phosphoglycerate mutase-B as well as formation of a noncovalent complex containing ubiquitin and phosphoglycerate mutase-B increases in colorectal cancer and novel modification of phosphoglycerate mutase-B might have a pathophysiological role. 相似文献
172.
In male hypogonadism associated with bone loss, it is important to determine whether bone loss continues with ageing and an increased risk of fracture. We studied bone metabolism in 86 male leprosy patients, who were classified according to the presence or absence of osteoporosis. Osteoporosis was present when men had lumbar compression fractures or a mean BMD-2SD that of normal Japanese men in each age decade. Four men had fractures. Serum concentrations of 1,25-dihydroxyvitamin D and high-sensitivity parathyroid hormone were almost normal in both groups, whereas free testosterone and oestradiol were significantly lower in the osteoporosis group than in the non-osteoporosis group (free testosterone: P < 0.01, oestradiol: P < 0.05). The urinary concentrations of pyridinoline and deoxypyridinoline, as a marker of bone absorption, were significantly higher in the osteoporosis group than in the non-osteoporosis group (pyridinoline: P < 0.01, deoxypyridinoline: P < 0.01). The serum concentration of osteocalcin, a marker of bone formation, was significantly higher in the osteoporosis group than in the non-osteoporosis group (P < 0.01). Elevated concentration means that bone repair is increased possibly because of compensation mechanisms for increased bone loss. In the osteoporosis group, hypogonadism occurred, and high bone turnover continued even in older men. We recommend clinical studies of treatment such as replacement therapy to prevent bone loss and increasing risk of fractures in older men with leprosy. 相似文献
173.
M Matoba S Matsui T Hirakawa T Aoyama F Takeda T Asaji H Doyousita H Enyama T Fukuoka H Nakatou 《Japanese circulation journal》1990,54(1):57-61
Factors determining prognosis in 100 patients with recent onset of congestive heart failure (CHF) were evaluated. The 1 year, 3 year, 5 year, and 10 year survival rates in the entire CHF group were 78.5%, 59.8%, 50.4% and 14.7%, respectively. No correlations between age, sex, heart rate and cardiothoracic ratio, and the cumulative survival rate were found. The prognosis of patients with CHF due to underlying coronary artery disease or primary cardiomyopathy was poor compared with that of patients with other types of heart disease. Patients whose NYHA classification was class III or VI had a significantly lower survival rate than those in class II. Patients with lower left ventricular stroke work and consecutive ventricular premature depolarization also had a significantly lower survival rate. These results suggest that functional status, underlying heart disease, left ventricular stroke work, and the presence of ventricular tachycardia provide important information regarding the long-term prognosis in patients with congestive heart failure. 相似文献
174.
Phenotypic consequences of ras oncogene expression were studied in cells conditionally transformed by T24 H-ras and a temperature-sensitive SV40 large T antigen (tsA58). Previous studies have demonstrated that transformation of REF52 cells by ras and SV40 large T antigen requires continuous T antigen expression. Thus, tsA58/T24 H-ras transformants ceased growing when transferred to a restrictive temperature for T antigen expression. Inhibition of cell growth was accompanied by massive accumulations of cholesterol esters, triglycerides and a third lipid species, identified as glycerol ethers on the basis of mobility on TLC. Cholesterol esters were derived from serum lipoproteins, and appeared to accumulate because LDL receptor expression and activity did not decline in growth arrested cells. Triglycerides and glycerol ethers were products of cell metabolism. The process lacked features characteristic of adipocyte differentiation, but may suggest mechanisms important in diseases, such as atherosclerosis, that involve abnormal accumulations of neutral lipids. Accumulating lipid species may also include metabolites induced by ras that accumulate in growth-arrested cells. 相似文献
175.
Tomoyasu Higuchi Yoshimasa Takeda Megumi Hashimoto Osamu Nagano Masahisa Hirakawa 《Journal of cerebral blood flow and metabolism》2002,22(1):71-79
Forty rats were subjected to 3 hours of focal ischemia by occluding the left middle cerebral and left common carotid arteries. The propagation of recurrent depolarization around the ischemic core was analyzed using direct-current potential and NADH (reduced nicotinamide adenine dinucleotide) fluorescence images by irradiating the parietal-temporal cortex with ultraviolet light. Based on histological evaluation at direct-current recording sites, the total time of depolarization causing 50% neuronal injury was estimated to be 18.2 minutes. The sites showing recurrent depolarizations resulted in 23 +/- 29% neuronal injury due to the short depolarization time, whereas the sites showing recurrent depolarizations and eventually persistent depolarization resulted in infarction. The NADH fluorescence images showed that recurrent depolarizations propagated along the margin of the ischemic core. In 85.9% of the recurrent depolarizations, the fluorescence disappeared without leaving any traces and did not affect the area of the ischemic core. However, in 47.5% of the animals, 14.1% of recurrent depolarizations merged with the ischemic core and increased the area by 6 +/- 4 mm(2). These findings suggest that recurrent depolarization increases the severity of neuronal injury but does not cause infarction by itself if persistent depolarization does not follow, and that the area of persistent depolarization is enlarged with 14.1% of recurrent depolarizations. 相似文献
176.
We evaluated the effect of nitroglycerin and nicardipine on ICG excretion during halothane anesthesia in man. Induced hypotension with nitroglycerin during halothane anesthesia produced a significant prolongation in ICG excretion. No such significant prolongation occurred in the patients who received nicardipine. The results suggest that a reduction in hepatic blood flow during anesthesia may be much less in patients who receive halothane with nicardipine than in those who receive halothane with nitroglycerin. 相似文献
177.
178.
A three-year-old boy with a progressive history of headache, vomiting and ataxia in the course of 2 months, was admitted on August 1983, when he was lethargic. Neurological examination revealed dysphagia, scanning speech and tremor in the bilateral hand. CT scan showed a very large enhanced mass in the center of posterior fossa with central necrosis in it and the dilatation of whole ventricular system. Suboccipital craniectomy was immediately performed and the tumor that occupied the vermis and invaded into both cerebellar hemisphere was subtotally removed. Postoperative irradiation was well performed: 4140 rads to the whole brain and 3162 rads to the spinal cord. However, 5 months later, facial palsy in the left side and progressive ataxia became prominent. CT scan showed multiple enhanced masses in the left trigonum and right anterior horn of the lateral ventricles and in the left cerebellopontine angle. In spite of chemotherapy, the patient had a down-hill course, especially after the ventricular hemorrhage, and died on June 9th, 1984. Histologically, the tumor had a lobulated appearance with an aggregation of tumor cells encircled by vascular septae. The cells within lobules generally had vesicular nuclei, which were arranged in parallel row. Occasionally smaller hyperchromatic cells with scant cytoplasm were present along the vascular septae. Reticulin was present within the septa, but was not observed within the lobules. Scattered astrocytic cells and processes were identified within the lobules by the immunoperoxidase technique for GFAP. The fibrillary cytoplasmic processes within the lobules were stained by immunoperoxidase technique for neurofilament (68K).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
179.
M Suzuki Y Harada H Hirakawa K Hirakawa R Omura 《Archives of oto-rhino-laryngology》1987,244(4):215-217
The frog Rana nigromaculata was used as an experimental model. The utricle and its nerve were isolated with the anterior and the lateral semicircular canal ampullae in frog Ringer's solution. The utricular otoconia and the otoconial membrane were then carefully removed. The halved anterior canal cupula was next placed in the tip of a glass microelectrode, which was mounted on a micromanipulator. The cupula was placed in the center of either the medial or the lateral part of the macula and was moved toward or away from the striola along the axis vertical to the striola. When the medial part of the macula was stimulated, 5 micron of striolapetal cupular movement elicited an excitatory nerve discharge. When the lateral part of the macula was stimulated, the striolapetal stimulus likewise induced an excitatory response. These results indicate the existence of physiological polarity on the utricular macula. 相似文献
180.
Role of blood transfusion in organ system failure following major abdominal surgery. 总被引:2,自引:1,他引:1
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Using multivariate probit analysis, the data of 565 patients who underwent major abdominal surgery were retrospectively analyzed, and the etiologic role of blood transfusion in organ system failure (OSF), which includes respiratory failure, gastrointestinal stress bleeding, renal failure, nonobstructive, nonhepatitic jaundice, and coagulopathy, was studied. Apart from the amount of blood transfusion, the following factors were included in the analysis as possible contributors to OSF: age, preoperative hematocrit, organ failure risk (diffuse peritonitis, obstructive cholangitis, liver cirrhosis, terminal cancer, and hemorrhagic shock), operative time, blood loss, and postoperative highest hematocrit. The results showed that, except for preoperative hematocrit, all the factors are statistically significant contributors, blood transfusion being the most significant. There was no statistically significant interaction between blood transfusion and organ failure risk. It is concluded that blood transfusion is an important, independent factor contributing to OSF, and its contribution cannot be attributed to the underlying conditions that require blood transfusion. 相似文献