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51.
BACKGROUND: The aim of this retrospective study was to identify reliable predictive factors for local control of hypopharyngeal cancer (HPC) treated by radiotherapy. METHODS: A cohort of 38 patients with HPC treated by radical radiotherapy at the National Cancer Center Hospital East between 1992 and 1999 were selected as subjects for the present study. Paraffin-embedded pre-therapy biopsy specimens from these patients were used for immunostaining to evaluate the relationships between local tumor control and expression of the following previously reported predictive factors for local recurrence of head and neck cancer treated by radiotherapy: Ki-67, Cyclin D1, CDC25B, VEGF, p53, Bax and Bcl-2. The predictive power of microvessel density (MVD) in biopsy specimens and of clinicopathologic factors (age, gender and clinical tumor-node-metastasis stage) was also statistically analyzed. RESULTS: Twenty-five patients developed tumor recurrence at the primary site. Univariate analysis indicated better local control of tumors with high microvessel density [MVD >or= median (39 vessels/field)] than with low MVD (< median, P = 0.042). There were no significant associations between local control and expression of Ki-67 (P = 0.467), Bcl-2 (P = 0.127), Bax (P = 0.242 ), p53 (P = 0.262), Cyclin D1 (P = 0.245), CDC25B (P = 0.511) or VEGF (P = 0.496). Clinicopathologic factors were also demonstrated to have no significant influence on local control (age, P = 0.974; gender, P = 0.372; T factor, P = 0.602; N factor, P = 0.530; Stage, P = 0.499). CONCLUSION: Microvessel density in biopsy specimens was closely correlated with local control of HPC treated by radiotherapy.  相似文献   
52.
We have discovered a novel topoisomerase II (topo II) poison, ER-37328 (12,13-dihydro-5-[2-(dimethylamino)ethyl]-4H-benzo[c]py-rimido[5,6,1- jk ]carbazole-4,6,10(5H, 11H)-trione hydrochloride), which shows potent tumor regression activity against Colon 38 cancer inoculated s.c. Here, we describe studies on the cell-killing activity against a panel of human cancer cell lines and the antitumor activity of ER-37328 against human tumor xenografts. In a cell-killing assay involving 1-h drug treatment, ER-37328 showed more potent cell-killing activity (50% lethal concentrations (LC50s) ranging from 2.9 to 20 μM ) than etoposide (LC50s>60 μM ) against a panel of human cancer cell lines. ER-37328 induced double-stranded DNA cleavage, an indicator of topo II-DNA cleavable complex formation, within 1 h in MX-1 cells, and the extent of cleavage showed a bell-shaped relationship to drug concentration, with the maximum at 2.5 μM . After removal of the drug (2.5 μM ) at 1 h, incubation was continued in drug-free medium, and the amount of cleaved DNA decreased. However, at 10 μM , which is close to the LC50 against MX-1 cells, DNA cleavage was not detected immediately after 1-h treatment, but appeared and increased after drug removal. This result may explain the potent cell-killing activity of ER37328 in the 1-h treatment. In vivo , ER-37328 showed potent tumor regression activity against MX-1 and NS-3 tumors. Moreover, ER-37328 had a different antitumor spectrum from irinotecan or cisplatin against human tumor xenografts. In conclusion, ER-37328 is a promising topo II poison with strong cell killing activity in vitro and tumor regression activity in vivo , and is a candidate for the clinical treatment of malignant solid tumors. (Cancer Sci 2003; 94: 119–124)  相似文献   
53.
Progressive renal impairment associated with acute intermittent porphyria is not well recognized and the mechanism of renal damage remains unclear. We report a case of a 51-year-old female with acute intermittent porphyria and long-term follow-up who developed proteinuria and renal insufficiency. Her biopsy showed marked tubulointerstitial damage with mitochondrial abnormalities. Urinary excretion of lipid peroxidation was increased compared to healthy controls. The porphyrin precursors may increase lipid peroxidation products and damage mitochondria leading to tubulointerstitial nephritis.  相似文献   
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Bromoisovalerylurea (bromisovalum) is a sedative-hypnotic given orally as a racemic mixture of optical isomers (i.e., (+)- and (-)-enantiomer) and frequently taken in overdose in order to commit suicide. Sera from 16 overdosed subjects were analyzed for each enantiomer by high-performance liquid chromatography on chiral stationary phases. The (+)-enantiomer concentration was lower than the (-)-enantiomer concentration in all specimens, that is, the ratio of the (+)-enantiomer to the total concentration ranged from about 50% to 0%. The ratio of the (+)-enantiomer was continuously decreasing in each subject. The data indicate that the drug in gastrointestinal tract was absorbed into blood nonstereoselectively and that the drug in blood was eliminated stereoselectively. The enantioselective determination of this drug will give useful information on absorption and elimination.  相似文献   
56.
We report a case of a 23-year-old Japanese woman who had severe hyperparathyroidism associated with chronic renal failure before the start of dialysis treatment. Her chief complaints were swelling and pain in both shoulders. Laboratory examination revealed renal failure (BUN 134 mg/dl, serum Cr 7.3 mg/dl), severe normocytic normochromic anemia (hemoglobin 4.3 g/dl), hypercalcemia (11.8 mg/dl), and hyperphosphatemia (9.7 mg/dl). Serum PTH levels were extremely increased (intact PTH >1,000 pg/ml: normal range 10-50 pg/ml). X-ray examination of the skull and shoulders showed a salt and pepper appearance, and cauliflower-like deformity of the distal end of both clavicles, respectively. Accelerated ectopic calcification was observed in the costal cartilages, internal carotid arteries, and splenic arteries. Ultrasonographic examination revealed enlargement of the four parathyroid glands. Thallium-technetium subtraction scintigraphy of the parathyroid glands showed increased uptake into the upper two. Renal needle biopsy revealed severe impairment of the interstitium and tubules with much milder changes in glomeruli. The etiology of the renal failure could not be identified. Hemodialysis, total parathyroidectomy and auto-transplantation into the forearm were immediately performed. The pathological diagnosis was chief cell hyperplasia of the parathyroid glands. Based on the presence of chronic renal failure, remarkable hyperphosphatemia with mild hypercalcemia, an unusually high level of serum PTH, and accelerated ectopic calcification, the patient was diagnosed to have severe secondary hyperparathyroidism caused by chronic renal failure with major impairment of the renal interstitium and tubules.  相似文献   
57.
Background The aim of this study was to observe time course changes in type II collagen synthesis in various regions of articular cartilage affected with osteoarthritis (OA) by examining the expression of type II collagen C-propeptide (pCOL II-C) and mRNA in a rabbit OA model. Methods Osteoarthritis was experimentally induced by partial lateral meniscectomy in the knees of Japanese white rabbits. The cartilage of the animals was then examined histologically over time. The degenerative area of articular cartilage was divided into three areas, according to the degree of degeneration. The ability to synthesize type II collagen was estimated by the immunohistological staining of pCOL II-C and the in situ hybridization of mRNA in type II collagen. Results The positive rate of pCOL II-C immunostaining in chondrocytes was highest in the central-degenerative region 1 week after surgery, and the highest rate in the para-degenerative region was observed 2 and 4 weeks after surgery. The percentage of pCOL II-C positive cells increased as the histological degeneration score increased to moderate degeneration and then decreased with further progression of the severity of cartilage degeneration. Examination by in situ hybridization revealed that the regions marked by strong pCOL II-C mRNA expression were similar to those indicated by the immunohistology results. Conclusions These results suggest that the type II collagen-synthesizing potential of chondrocytes is highest in moderately degenerated areas of OA articular cartilage. Cartilage repair continues to be seen even as OA advances, although the reaction varies depending on the stage of OA.  相似文献   
58.
A 26-year-old female visited our hospital complaining left flank pain and macroscopic hematuria. She had been suffering ulcerative colitis and administered salazosulphapyridine and predonisolone from 17-year-old. Intravenous urography showed radiolucent multiple stones in the left renal pelvis. Three sessions of extracorporeal shock wave lithotripsy were performed after ureteral stenting. Although disintegration and discharge of the stones were satisfactory, bladder stone induced by ureteral stent was complicated. The extracted bladder stone showed a yellowish brown color and the surface was granular shape. Composition of the stone was acetyl sulphapyridine which was a metabolite of salazosulphapyridine. After maintenance of the urinary pH ranges between 6.5 and 7.5 by medication of sodium bicarbonate, the patient remains free of stone for 3 years. Drug induced urolithiasis originated from salazosulphapyridine is extremely rare. Satisfactory oral fluid intake and urinary alkalization are important for prevention of sulpha drugs calculi of urinary tract.  相似文献   
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Elevated production of cysteinyl leukotrienes (cysLTs) from sinus tissues and abundant sinus eosinophils are characteristic features of chronic hyperplastic eosinophilic sinusitis (CHS). CysLTs exert their action through G-protein-coupled receptors named cysLTs receptor type I (cysLT1R) and type II (cysLT2R). These expressions of cysLT receptors in the sinus mucosa have yet to be clarified and the relationship between eosinophilia and the expression of these receptors remains obscure. We compared the expressions of cysLT1R and cysLT2R in the sinus mucosa in patients with CHS, non-eosinophilic chronic sinusitis (NECS), and control sinus tissues; and analyzed the correlation between the expression of CysLTRs and the presence of sinus eosinophils by immunohistochemistry and real-time PCR. A significantly higher percentage of eosinophils expressing cysLT2R protein was observed in patients with CHS compared with NECS and controls. In addition, cysLT2R mRNA expression in CHS was significantly higher than in NECS and controls. Furthermore, a positive correlation was observed between cysLT2R mRNA expression and the number of infiltrated eosinophils. In contrast, the cysLT1R mRNA expression did not differ significantly among these groups. The effect of cysLTs on sinus eosinophils may be mediated through the cysLT2R in patients with CHS. These results may suggest the therapeutic benefit of cysLT2R antagonists in CHS.  相似文献   
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