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991.
We report two cases of urolithiasis related to anorexia nervosa and laxative abuse. Case 1: A 21-year-old woman was referred to our hospital because of left flank pain. A left ureteral stone, 10 x 6 mm in size, was successfully fragmented by extracorporeal shock-wave lithotripsy (ESWL), but she experienced repetitive formation of bilateral urinary stones and double J stent encrustation which required 13 sessions of ESWL, one session of transurethral ureterolithotripsy and one session of cystolithotripsy over a period of 5 years. All stones were comprised of pure ammonium acid urate. It was later revealed that she was diagnosed with anorexia nervosa at 15 years old and had suffered from laxative abuse (bisacodyl, 300-500 mg/day) ever since. Case 2: A 18-year-old woman was referred to our hospital because of left lower abdominal pain. A left renal stone, 15 x 10 mm in size, was successfully fragmented by ESWL, but she had double J stent encrustation which was managed by cystolithotripsy. All stones were comprised of pure ammonium acid urate. She was later diagnosed with anorexia nervosa and it turned out that she had suffered from an eating disorder and laxative abuse (bisacodyl, 200 mg/day) since the age of 15 years. Both patients had marked decrease in urine volume, hyponatremia and hypokalemia. Anorexia nervosa and laxative abuse should be suspected whenever a woman has an ammonium acid urate stone in sterile urine because the treatment of these disorders is crucial to the prevention of repetitive formation of urinary stones. 相似文献
992.
Functional properties of hyalocytes under PDGF-rich conditions 总被引:3,自引:0,他引:3
Noda Y Hata Y Hisatomi T Nakamura Y Hirayama K Miura M Nakao S Fujisawa K Sakamoto T Ishibashi T 《Investigative ophthalmology & visual science》2004,45(7):2107-2114
PURPOSE: To investigate the functional properties and intracellular signaling of hyalocytes under platelet-derived growth factor (PDGF)-rich conditions. METHODS: The hyalocytes were isolated from bovine eyes and identified by immunocytochemistry and electron microscope. The expression of PDGF receptor alpha/beta and its phosphorylation in response to PDGF-BB was analyzed by Western blot analysis. PDGF-BB-induced proliferation and migration were evaluated by thymidine uptake and Boyden's chemotaxis assay. The expression of the urokinase-type plasminogen activator (uPA) gene and the fibrinolytic activity were assessed by Northern blotting and fibrin zymography. An in vitro type I collagen gel contraction assay was performed to determine the effect of PDGF-BB on cellular contraction. RESULTS: The hyalocytes were immunocytochemically positive for S-100 and negative for glial fibrillary acidic protein (GFAP) and cytokeratin, as previously described. The electron microscope demonstrated that hyalocytes possess lysosome-like granules, mitochondria, and micropinocytotic vesicles in their cytoplasm. The hyalocytes expressed PDGF receptor alpha and beta, both of which were immediately phosphorylated in response to PDGF-BB. PDGF-BB also activated p85 PI3-kinase, p44/p42 mitogen-activated protein (MAP) kinase and p38 MAP kinase. PDGF-BB induced thymidine uptake and migration in a concentration-dependent (0-10 ng/mL) manner. Inhibitors of the respective kinases prohibited PDGF-BB-dependent thymidine uptake and migration with the exception of the p44/p42 MAP kinase inhibitor, which displayed no inhibitory effects on migration. PDGF-BB increased uPA gene expression and fibrinolytic activity. Collagen gel contraction observed under PDGF-BB-rich conditions was not prohibited by the respective inhibitors investigated. CONCLUSIONS: The hyalocytes demonstrated macrophage-like characteristics and may have both physiologic and pathologic roles, such as the maintenance of vitreous transparency through fibrinolytic activity and the pathogenesis of proliferative-vitreoretinal diseases through cellular proliferation and vitreous hyper-contraction. 相似文献
993.
Both BRAF and KRAS mutations are rare in colorectal carcinomas from patients with hereditary nonpolyposis colorectal cancer 总被引:2,自引:0,他引:2
The BRAF mutations have been suggested to be linked with defective mismatch repair in colorectal carcinomas. To clarify the extent of BRAF mutations in HNPCC colorectal carcinomas, which are typical mismatch repair deficient carcinomas, we compared the frequency of BRAF mutations between HNPCC, familial adenomatous polyposis (FAP) and sporadic cases. The frequency of KRAS mutations was also compared between these three syndromes. No BRAF mutations were detected in 33 HNPCC colorectal carcinomas, while they were detected in 3 of 26 (12%) FAP carcinomas and 2 of 53 (4%) microsatellite stable sporadic carcinomas. KRAS mutations were detected in 2 of 33 (6%) HNPCC, 9 of 26 (35%) FAP and 18 of 53 (34%) sporadic carcinomas. Such extremely low frequencies of BRAF and KRAS mutations in HNPCC colorectal carcinomas suggest that the participation of RAS-RAF signaling is minor in HNPCC, and that the previously suggested high frequency of BRAF mutations in mismatch repair deficient colorectal carcinomas is not due to mutations of mismatch repair genes. 相似文献
994.
Kawahara K Yoshida Y Kurokawa T Suzuki Y Nagahara K Tsuchida T Okazawa H Fujibayashi Y Yonekura Y Kotsuji F 《Journal of computer assisted tomography》2004,28(4):505-516
OBJECTIVE: To determine whether positron emission tomography (PET) with tracer 18-fluorodeoxyglucose (FDG-PET) yields additional information in the diagnosis of malignancy compared with magnetic resonance imaging (MRI) findings in selected women after screening for ovarian masses by ultrasonography (US). METHODS: After 49 patients were screened by US and physical examination (including a pelvic examination) by 2 experienced gynecologic oncologists, 38 patients suspected of having ovarian cancer were enrolled in the study. All 38 underwent MRI and FDG-PET. The results of the histologic findings were used to assess the accuracy of the imaging findings. RESULTS: Of the 38 women, 23 had malignant lesions and 15 had benign lesions. Magnetic resonance imaging, PET, and MRI with FDG-PET diagnoses had sensitivities of 91%, 78%, and 91%, respectively; specificities of 87%, 87%, and 87%, respectively; and diagnostic accuracy of 92%, 82%, and 92%, respectively. CONCLUSION: The addition of FDG-PET to MRI does not yield significant additional information for differentiation of benign from malignant ovarian masses in selected women after US. 相似文献
995.
Measurement of vascular diameter in vitro by automated software for CT angiography: effects of inner diameter, density of contrast medium, and convolution kernel 总被引:11,自引:0,他引:11
Suzuki S Furui S Kaminaga T Yamauchi T 《AJR. American journal of roentgenology》2004,182(5):1313-1317
OBJECTIVE: This investigation was performed to evaluate the accuracy of diameter measurement of vessels in vitro by automated software for CT angiography. MATERIALS AND METHODS: Vascular models with three inner diameters ( approximately 3, 4, and 6 mm) filled with contrast medium of three different densities ( approximately 460, 350, and 210 H) were scanned with helical CT. Five convolution kernels (soft, standard, detail, bone, and lung) were used. We evaluated the measurement error, defined as the difference between the diameter measured by the automated software and the true inner diameter of the vascular model. Statistical analysis involved three-way analysis of variance with repeated measures. RESULTS: Significant differences occurred in measurement error among the three vascular model inner diameters, among the three densities of intravascular contrast medium, and among the five convolution kernels (p < 0.01). In all the convolution kernels except lung, measurement errors progressively decreased with higher densities of intravascular contrast medium (p < 0.01). In vascular models filled with contrast medium of 350 H, measurement errors were significantly smaller in soft (mean +/- standard deviation [SD], 0.29 +/- 0.16 mm) and bone (0.23 +/- 0.05 mm) than in other convolution kernels (p < 0.01). CONCLUSION: The accuracy of diameter measurement was affected by the vascular model inner diameter, the density of contrast medium, and the convolution kernel. A higher density of intravascular contrast medium and selection of the proper convolution kernel will improve accuracy. 相似文献
996.
Purpose In view of the increasing number of patients diagnosed with lung cancer every year worldwide, there is an urgent need for an effective screening marker to improve its early detection.Methods We quantified the level of immunoreactive proteins for the tissue inhibitors of metalloproteinase (TIMP)-1 and TIMP-2 in the sera of 54 patients with non-small cell lung cancer (NSCLC) and 25 healthy control subjects, by using enzyme-linked immunosorbent assays with specific monoclonal antibodies.Results The TIMP-1 level was significantly higher, and the TIMP-2 level was significantly lower in the patients with NSCLC than in the controls. Furthermore, both TIMP-1 and TIMP-2 were significantly higher in patients with squamous cell carcinoma than in those with adenocarcinoma. The TIMP-1 level in patients with stage III/IV disease was significantly higher than that in those with stage I/II disease. The TIMP-1/TIMP-2 ratio was significantly higher in the patients with NSCLC, and the receiver-operating characteristic curves analysis revealed that the TIMP-1/2 ratio, but not TIMP-1 or -2 alone, was a better screening marker for NSCLC than carcinoembryonic antigen (P < 0.0001). Patients with a high TIMP-1 value had significantly shorter disease-free survival (P = 0.0479), but those with a high TIMP-1/2 ratio did not.Conclusion The TIMP-1/2 ratio may be a good screening marker of NSCLC; however, it was less effective than TIMP-1 as a prognostic factor. 相似文献
997.
Bando H Ikuno Y Choi JS Tano Y Yamanaka I Ishibashi T 《American journal of ophthalmology》2005,139(1):197-199
PURPOSE: To reveal the pathogenesis of myopic foveoschisis (MF). DESIGN: Clinicopathological report. METHODS: Internal limiting membranes (ILMs) were collected from ten patients with MF and five patients with idiopathic macular hole (IMH) as a control. Samples were subjected to transmission electron microscopic study. Characteristics of the ILM were compared between the two groups. RESULTS: Collagen fiber and cell debris were identified on the inner surface of ILM in seven eyes (70%) with MF, significantly more (P < .05) than found in IMH subjects (0%). More fibrous glial cells were likely to be found on the inner surface of ILM. No significant difference in fibroblast-like cell adhesion was observed. CONCLUSIONS: Collagen fiber and cellular component are suggested to play an important role in developing MF. ILM peeling may be essential for vitrectomy for MF. 相似文献
998.
Corneal barrier function, tear film stability, and corneal sensation after photorefractive keratectomy and laser in situ keratomileusis 总被引:2,自引:0,他引:2
Nejima R Miyata K Tanabe T Okamoto F Hiraoka T Kiuchi T Oshika T 《American journal of ophthalmology》2005,139(1):64-71
PURPOSE: To compare corneal sensation, corneal barrier function, tear secretion, and tear film stability after photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK). DESIGN: Prospective, nonrandomized clinical trial. METHODS: In a prospective study, 28 eyes of 15 patients underwent PRK and 115 eyes of 59 patients underwent LASIK to correct myopia. Corneal sensation, corneal epithelial barrier function, tear secretion, and tear film stability were examined preoperatively and 1 week and 1, 3, 6, and 12 months postsurgery. RESULTS: Both PRK and LASIK significantly compromised corneal sensation, increased epithelial barrier function, reduced tear secretion, and deteriorated tear film stability (P < .05, Wilcoxon signed-rank test). Deterioration of corneal sensation was significantly greater after LASIK than after PRK by 3 months postoperatively (P < .05, Wilcoxon rank sum test). Increases in corneal epithelial permeability were more prolonged after LASIK than after PRK. A significant intergroup difference in permeability was observed 1 month after surgery (P < .01). Tear breakup time was significantly shorter in the LASIK group than in the PRK group up to 3 months after surgery (P < .045). CONCLUSIONS: LASIK induces greater and more prolonged damage to corneal sensation, corneal barrier function, and tear film stability than PRK. 相似文献
999.
Triplet chemotherapy with cisplatin, gemcitabine and vinorelbine for malignant pleural mesothelioma 总被引:2,自引:1,他引:1
Maruyama R Shoji F Okamoto T Miyamoto T Miyake T Nakamura T Ikeda J Aoki Y Wataya H Asoh H Ichinose Y 《Japanese journal of clinical oncology》2005,35(8):433-438
BACKGROUND: The incidence of malignant pleural mesothelioma (MPM) is expected to increase due to delayed control of occupational exposure to asbestos in Japan. We investigated the use of triplet combination chemotherapy with cisplatin (CDDP), gemcitabine (GEM) and vinorelbine (VNR) for the treatment of Japanese patients with MPM. METHODS: From December 2000 to August 2003, 12 patients received the following regimen: CDDP 40 mg/m(2), GEM 800 mg/m(2) and VNR 20 mg/m(2) on days 1 and 8 every 4 weeks. Among the 12 patients, six selected patients underwent an extrapleural pneumonectomy (EP) after a median of three cycles of triplet chemotherapy. RESULTS: The overall response rate for all patients and the response rate for chemotherapy-naive cases were 58 and 67%, respectively. The median survival time and survival rate at 2 years for all patients were 11 months and 50%, respectively. The 2-year survival rates for the patients with and without EP were 83.3 and 16.7%, respectively. CONCLUSIONS: Triplet chemotherapy with CDDP, GEM and VNR was thus found to be highly effective for patients with MPM and its toxicity was manageable. A multi-institutional phase II trial is now being planned to establish the effectiveness of this new regimen in chemotherapy-naive patients with MPM. 相似文献
1000.
Okuyama-Yamamoto A Yamamoto T Miki A Terashima T 《The European journal of neuroscience》2005,21(9):2586-2592
To explore the functional roles of Reelin in the adult olfactory system, we examined changes in the expression of reelin mRNA and Reelin protein in the olfactory bulb (OB) of adult mice after a chemical lesion to the olfactory epithelium. Following intranasal irrigation with 2% zinc sulphate solution, animals were perfused at various times between 5 and 40 days post-lesion. The expression of reelin mRNA in mitral cells in the OB was slightly reduced at 5 days post-lesion, completely abolished by 20 days, but restored almost to the normal level at 40 days post-lesion. Similarly, the expression of Reelin protein in mitral cells of the deafferented OB also recovered, although not to the normal level. No recovery of either reelin mRNA or Reelin immunoreactivity was seen in the periglomerular cells and external tufted cells. The expression profile of reelin mRNA and Reelin protein in the OB coincided with the time course of degeneration and regeneration of olfactory nerves, as indicated by anterograde labeling of olfactory nerves with WGA-HRP. These results suggest that expression of reelin mRNA in the adult OB is regulated by olfactory inputs. 相似文献