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991.
Pautrat K Bretagnol F de Muret A de Calan L 《Gastroentérologie clinique et biologique》2003,27(12):1163-1165
Glucagonoma is a rare islet alpha-cell pancreatic tumor. Patients usually present with necrolytic migratory erythema, diabetes mellitus, thromboembolism, and weight loss. Diagnosis is based on the presence of a pancreatic tumor in association with hyperglucagonemia. Tumor characterization is made by computed tomography and/or pancreatic endoscopic ultrasonic and indium-labeled octreo-scan. Surgery is the main component of the treatment, in some cases in association with chemotherapy. We report the case of a 72-year-old patient who developed a recurrent glucagonoma, 20 years after surgical resection. 相似文献
992.
Early light-induced proteins protect Arabidopsis from photooxidative stress 总被引:1,自引:0,他引:1 下载免费PDF全文
Hutin C Nussaume L Moise N Moya I Kloppstech K Havaux M 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(8):4921-4926
The early light-induced proteins (ELIPs) belong to the multigenic family of light-harvesting complexes, which bind chlorophyll and absorb solar energy in green plants. ELIPs accumulate transiently in plants exposed to high light intensities. By using an Arabidopsis thaliana mutant (chaos) affected in the posttranslational targeting of light-harvesting complex-type proteins to the thylakoids, we succeeded in suppressing the rapid accumulation of ELIPs during high-light stress, resulting in leaf bleaching and extensive photooxidative damage. Constitutive expression of ELIP genes in chaos before light stress resulted in ELIP accumulation and restored the phototolerance of the plants to the wild-type level. Free chlorophyll, a generator of singlet oxygen in the light, was detected by chlorophyll fluorescence lifetime measurements in chaos leaves before the symptoms of oxidative stress appeared. Our findings indicate that ELIPs fulfill a photoprotective function that could involve either the binding of chlorophylls released during turnover of pigment-binding proteins or the stabilization of the proper assembly of those proteins during high-light stress. 相似文献
993.
Modulation of gene expression induced in human epidermis by environmental stress in vivo 总被引:2,自引:0,他引:2
994.
Targeting of a novel fusion protein containing methioninase to the urokinase receptor to inhibit breast cancer cell migration and proliferation 总被引:2,自引:0,他引:2
Peron K Jones TN Gauthier SA Nguyen TN Zang XP Barriere M Prévéraud D Soliman CE Harrison RG Pento JT 《Cancer chemotherapy and pharmacology》2003,52(4):270-276
It has been shown that methionine depletion inhibits tumor cell growth and reduces tumor cell survival. A novel fusion protein targeted specifically to tumor cells was developed. The fusion protein contained two components: the amino terminal fragment of human urokinase (amino acids 1–49) that binds to the urokinase receptor protein expressed on the surface of invasive cancer cells, and the enzyme l-methioninase (containing 398 amino acids) which depletes methionine and arrests the growth of methionine-dependent tumors. The influence of the fusion protein on the growth and motility of human breast cancer cells was examined using a culture wounding assay. It was determined that MCF-7 breast cancer cells, used in this study, were methionine-dependent and that the fusion protein bound specifically to urokinase receptors of the surface of the cancer cells. Further treatment of the cancer cells with fusion protein over the concentration range 10–8 to 10–6 M produced a dose-dependent inhibition of both the migration and proliferation index of MCF-7 cells in the culture wounding assay over a period of 1 to 3 days. The results of this study suggest that this novel fusion protein may serve as a prototype for specific targeting of methioninase and perhaps other cytotoxic agents to cancer cells.Abbreviations ATF Amino-terminal fragment of urokinase (amino acids 1–49) - PMSF Phenylmethylsulfonyl fluoride - SDS-PAGE Sodium dodecyl sulfate-polyacrylamide gel electrophoresis - TPCK N-p-Tosyl-l-phenylalanine chloromethyl ketoneK.P. and S.A.G. are intern students from Blaise Pascal University, Clermont-Ferrand, France. M.B. and D.P. are intern students from the University of Limoges, France. 相似文献
995.
Absolute configuration of a tetrahydrophenanthrene from Heliotropium ovalifolium by LC-NMR of its Mosher esters 总被引:1,自引:0,他引:1
Guilet D Guntern A Ioset JR Queiroz EF Ndjoko K Foggin CM Hostettmann K 《Journal of natural products》2003,66(1):17-20
A new tetrahydrophenanthrene (1, (1R,2R)-1-hydroxy-2-methoxy-6,9-dimethyl-2,3-dihydrophenanthren-4(1H)-one (heliophenanthrone)) has been isolated from the aerial parts of Heliotropium ovalifolium. Its structure was elucidated on the basis of spectroscopic data, and the absolute configuration of the asymmetric centers was determined from LC-NMR data of the Mosher ester derivatives. 相似文献
996.
Functional proteomic analysis of melanoma progression 总被引:6,自引:0,他引:6
Bernard K Litman E Fitzpatrick JL Shellman YG Argast G Polvinen K Everett AD Fukasawa K Norris DA Ahn NG Resing KA 《Cancer research》2003,63(20):6716-6725
Functional proteomics provides a powerful approach to screen for alterations in protein expression and posttranslational modifications under conditions of human disease. In this study, we use protein screening to examine markers of melanoma progression, by profiling melanocyte versus melanoma cell lines using two-dimensional electrophoresis and mass spectrometry. Eight candidate markers were identified as differentially regulated in transformed cells. In particular, hepatoma-derived growth factor (HDGF) and nucleophosmin B23 were strongly correlated with melanoma. Nucleophosmin B23 is a nucleolar and centrosome-associated protein, which has been implicated as a target for cyclin E/cyclin-dependent kinase 2 (CDK2) in modulating centrosome duplication and cell cycle control. Western blotting of one-dimensional and two-dimensional gels showed that the form of nucleophosmin B23 that is up-regulated in melanoma represents a posttranslationally modified form, most likely reflecting enhanced phosphorylation in the tumor-derived cells. In contrast, Western analysis of HDGF demonstrated increased expression of all forms in melanoma cell lines compared with melanocytes. Immunohistochemical analysis of human tissue biopsies showed strong expression of HDGF in early and late stage melanomas and low expression in melanocytes and nontumorigenic nevi. Interestingly, biopsies of nevi showed a graded effect in which HDGF immunoreactivity was reduced in nevoid nests penetrating deep into the dermis compared with nests at the epidermal-dermal junction, suggesting that HDGF expression in nevi is dependent on epidermal cell interactions. In contrast, biopsies of melanoma showed strong expression of HDGF throughout the tumor, including cells located deeply within dermis. Thus, expression of this antigen likely reports a reduced dependence of protein expression on epidermal interactions. 相似文献
997.
Persistence and load of high-risk HPV are predictors for development of high-grade cervical lesions: a longitudinal French cohort study 总被引:37,自引:0,他引:37
Dalstein V Riethmuller D Prétet JL Le Bail Carval K Sautière JL Carbillet JP Kantelip B Schaal JP Mougin C 《International journal of cancer. Journal international du cancer》2003,106(3):396-403
Oncogenic HPV types are the major cause of worldwide cervical cancer, but only a small proportion of infected women will develop high-grade cervical intraepithelial neoplasia or cancer (CIN2/3+). We performed a prospective study including 781 women with normal, atypical squamous cells of undetermined significance (ASCUS) or low-grade squamous intraepithelial lesion (LGSIL) cytology, and infected or not by high-risk (HR) HPV tested by Hybrid Capture II. Women were followed up every 6 months for a median period of 22 months. Among the HR-HPV-positive women at entry, more than half cleared their virus in 7.5 months; the clearance rate was greater for low viral loads than for high loads and also was higher in women with an initial ASCUS/LGSIL smear than in women with normal cytology. The incidence of cytologic abnormalities strongly depended on baseline viral load and HR-HPV persistence. Maintenance of cytologic abnormalities was associated with the outcome of HR-HPV status (negative or =100 pg/mL). Conversely, women who were consistently HR-HPV negative or transiently HR-HPV positive, whatever the cytology at baseline was, did not develop CIN2/3+ during follow-up. Age seemed to affect only the rate of incident HR-HPV infection. In conclusion, our data suggest that women repeatedly tested positive for HR-HPV are at risk of developing CIN2/3+, even when initial cytology is normal. A high viral load could be used as a short-term marker of progression toward precancerous lesions, although lower load does not inevitably exclude progressive disease. 相似文献
998.
Nouette-Gaulain K Forestier F Malgat M Marthan R Mazat JP Sztark F 《Anesthesiology》2002,97(6):1507-1511
BACKGROUND: Adaptation to chronic exposure to hypoxia alters energy metabolism in the heart, particularly in the left ventricle, which undergoes a loss in oxidative capacity. Highly lipophilic local anesthetics interfere with mitochondrial energy metabolism. The purpose of this study was to compare the effects of bupivacaine on mitochondrial energy metabolism in heart of rats subjected to normoxic or hypoxic environments. METHODS: Male Wistar rats (n = 10) were subjected to hypobaric hypoxia (simulated altitude = 5,000 m, 380 mmHg) for 2 weeks. Control rats (n = 10) were maintained in an ambient normoxic environment. Mitochondrial metabolism (oxygen consumption and adenosine triphosphate synthesis) was assessed using saponin-skinned ventricular fibers. Bupivacaine (0-5 mM) was tested on both left and right ventricles of normoxic or hypoxic heart. RESULTS: In animals exposed to hypobaric hypoxia for 14 days, cardiac mass significantly increased, and the right-to-left ventricular ratio was approximately twofold (0.48 +/- 0.11 vs. 0.22 +/- 0.04, P < 0.05). Oxygen consumption and adenosine triphosphate synthesis were significantly lower in the hypoxic left ventricles but not in the right ones. The uncoupling effect of bupivacaine was more pronounced in the left ventricle from hypoxic heart than in the right ventricle; the bupivacaine-induced decrease in the adenosine triphosphate synthesis rate and in the adenosine triphosphate-to-oxygen ratio was significantly greater in the hypoxic left ventricle than in the normoxic one. CONCLUSIONS: Chronic hypoxia impairs cardiac energy metabolism in left ventricles and enhances the depressant effects of bupivacaine on mitochondrial functions. 相似文献
999.
Factor XIII replacement in stem-cell transplant recipients with severe hemorrhagic cystitis: a report of four cases 总被引:1,自引:0,他引:1
Demesmay K Tissot E Bulabois CE Bertrand MA Racadot E Woronoff-Lemsi MC Cahn JY Deconinck E 《Transplantation》2002,74(8):1190-1192
BACKGROUND: Hemorrhagic cystitis (HC) is an important cause of morbidity in patients undergoing allogeneic stem-cell transplantation (SCT). Various causes have been identified, such as the use of high-dose cyclophosphamide or busulfan and the occurrence of acute graft-versus-host disease or viral infections (cytomegalovirus, adenovirus, polyomavirus). METHODS: The clinical course of four patients treated with factor XIII (FXIII) concentrate for severe HC after allogeneic SCT is described. RESULTS: Four patients were treated with one or two infusions of 50 IU/kg of FXIII concentrate. Only one patient showed a plasmatic FXIII decrease before treatment. Three of the four patients responded to this treatment, and HC completely resolved in two of them. No adverse event was observed. CONCLUSION: The use of FXIII concentrate can improve the major symptoms of HC in patients with decreased or normal FXIII plasma level after allogeneic SCT. 相似文献
1000.
The aim was to evaluate hepatitis C surveillance in Poland during 1998. Hepatitis C reports were obtained from epidemiology offices. Public health staff were interviewed to collect information on surveillance operations. To estimate the proportion of acute cases among the total reported, a study was conducted in the Warsaw district to validate case reports. A total of 1661 (97.2%) hepatitis C cases were studied. Hepatitis C surveillance was timely and acceptable to the user, but did not provide a number of information elements required to differentiate acute from chronic cases of infection. Of the 268 case reports available in the Warsaw district, only 15 (5.6%) met the acute hepatitis C case definition. It is concluded that hepatitis C surveillance in Poland cannot provide useful incidence estimates and information regarding risk factors for acute infection. A strict case definition and a modified case form with specific questions for HCV transmission routes should be applied. 相似文献