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11.
Fuchs Robert P.P.; Lang Marie-Claude E.; Miller Elizabeth C.; Miller James A. 《Carcinogenesis》1981,2(7):655-659
Earlier studies showed that N-acetyl-2-aminofluorene (AAF) ismuch more carcinogenic than N-acetyl-2-amino-7-iodofluorene(AAIF). Subsequently it was found that substitution of C-8 ofguanine bases in DNA with AAF residues resulted in displacementof the guanine bases outside the DNA helix. This did not occurafter similar substitution with AAIF residues. As one approachto assessing the possible importance of this gross conformationaldifference to the carcinogenicity of AAF, the carcinogenic activitiesof two electrophilic esters, N-myristoyloxy-AAF and its 7-iododerivative, were compared by s.c. injection into male Fischerrats. On injection of a total of 64 µmol, each ester induceda high incidence of sarcomas, and the latent periods were similar.N-Myristoyloxy-AAIF was solvolyzed in aqueous media at aboutone-half the rate of N-myristoyloxy-AAF, and it was less than10% as reactive with native DNA as N-myristoyloxy-AAF. N-Myristoyloxy-AAFand N-myristoyloxy-AAIF were each less reactive than the correspondingacetoxy derivatives. These data suggest that the low carcinogenicityof AAIF as compared to that of AAF may not be associated withthe conformations of their adducts in the DNA. This differencein carcinogenicity may be related to differences in the ratesof metabolic activation and inactivation of these two amides. 相似文献
12.
Masahito Katoh Rick Wilmotte Marie-Claude Belkouch Nicolas de Tribolet Gianpaolo Pizzolato Pierre-Yves Dietrich 《Journal of neuro-oncology》2003,64(1):71-76
Survivin, a member of the inhibitor of apoptosis proteins gene family, was recently shown to be expressed by tumors originating from different cell lineages. There are also cumulative evidences that spontaneous immune response against survivin derived epitopes may occur. Here, using RT-PCR, Western-blot analysis and immunohistochemistry, we show that survivin is widely expressed by gliomas, meningiomas and schwannomas, both in vitro and in vivo. These data indicate that survivin may serve as an attractive target for immunotherapies designed for brain tumors. 相似文献
13.
Marie-Claude Rousseau Michal Abrahamowicz Luisa L Villa Maria Cecilia Costa Thomas E Rohan Eduardo L Franco 《Cancer epidemiology, biomarkers & prevention》2003,12(10):1029-1037
Women infected with multiple human papillomavirus (HPV) types seem to be at higher risk of cervical intraepithelial neoplasia, although there is controversy about whether coinfections are associated with lower or higher grades of dysplasia. There is no established risk factor profile for infection with multiple HPV types. We analyzed data from a prospective cohort of 2,075 Brazilian women to identify determinants of HPV coinfection. Cervical specimens were collected for cytology and HPV DNA detection. Data on baseline and time-dependent putative risk factors were obtained by interview. Baseline predictors of HPV coinfection included younger age, greater number of recent sexual partners, a history of condyloma but not of other sexually transmitted diseases, and younger age at first sexual intercourse. In repeated measures analyses, there was a weak positive association between the number of sexual partners in the time interval between two study visits and the risk of coinfection. Our results suggest that the risk factor profile for HPV coinfection among HPV-infected women shares several similarities with risk factors for any HPV infection. 相似文献
14.
Bonjour JP Brandolini-Bunlon M Boirie Y Morel-Laporte F Braesco V Bertière MC Souberbielle JC 《The British journal of nutrition》2008,100(4):866-874
Increased postmenopausal bone turnover leads to bone loss and fragility fracture risk. In the absence of osteoporosis, risk preventive measures, particularly those modifying nutritional lifestyle, are appropriate. We tested the hypothesis that milk supplementation affects bone turnover related to biochemical markers in a direction that, in the long term, may be expected to reduce postmenopausal bone loss. Thirty healthy postmenopausal women aged 59.3 (SD 3.3) years were enrolled in a prospective crossover trial of 16 weeks. After a 4-week period of adaptation with diet providing 600 mg calcium plus 300 mg ingested as 250 ml semi-skimmed milk, participants were maintained during 6 weeks under the same 600 mg calcium diet and randomized to receive either 500 ml semi-skimmed milk, thus providing a total of 1200 mg calcium, or no milk supplement. In the next 6 weeks they were switched to the alternative regimen. At the end of the each period, i.e. after 4, 10 and 16 weeks, blood and urinary samples were collected. The changes in blood variables between the periods of 6 weeks without and with milk supplementation were: for parathyroid hormone, -3.2 pg/ml (P=0.0054); for crosslinked telopeptide of type I collagen, -624 pg/ml (P<0.0001); for propeptide of type I procollagen, -5.5 ng/ml (P=0.0092); for osteocalcin, -2.8 ng/ml (P=0.0014). In conclusion, a 6-week period of milk supplementation induced a decrease in several biochemical variables compatible with diminished bone turnover mediated by reduction in parathyroid hormone secretion. This nutritional approach to postmenopausal alteration in bone metabolism may be a valuable measure in the primary prevention of osteoporosis. 相似文献
15.
Chairs Louis-Philippe Boulet Qutayba Hamid Co-authors of sections of the document Simon L Bacon C��line Bergeron Louis-Philippe Boulet Yue Chen Anne E Dixon Pierre Ernst Qutayba Hamid Fernando Holguin Charles G Irvin R John Kimoff Sushma Komakula Catherine Laprise Kim L Lavoie Stephanie A Shore Mihaela Teodorescu Marie-Claude Vohl 《Canadian respiratory journal》2007,14(4):201-208
Asthma and obesity are frequently associated, and obesity has been considered a factor contributing to both an increase in severity of asthma and to its development. The present document summarizes the proceedings of a symposium held in Montreal, Quebec, on November 2, 2006, under the auspices of the Réseau en santé respiratoire du Fonds de la recherche en santé du Québec in collaboration with the McGill University – Strauss Severe Asthma Program, Université Laval (Quebec City) and Université de Montréal. It includes an overview of the various aspects of the relationships between asthma and obesity with regard to animal models; genetic, hormonal and physiological determinants; influence of comorbidities (eg, sleep apnea syndrome); epidemiology; clinical and psychological features; and management of asthma in the obese population. 相似文献
16.
Christian Spaulding Marie-Claude Morice Bernard Lancelin Simon El Haddad Eric Lepage Sophie Bataille Jean-Pierre Tresca Xavier Mouranche Sandrine Fosse Mehran Monchi Nikita de Vernejoul 《European heart journal》2006,27(9):1054-1060
AIMS: In acute myocardial infarction (AMI), primary percutaneous transluminal angioplasty (PTCA) is the preferred option when it can be performed rapidly. Because of the limited access to high PTCA volume centres in some areas, it has been suggested that PTCA could be performed in low-volume centres on AMI patients. Little data exist on the validity of this strategy in modern era PTCA. METHODS AND RESULTS: The Greater Paris area comprises 11 million inhabitants and accounts for 18% of the French population. In 2001, the hospital agency of the Greater Paris area set up a registry of all PTCAs performed in this region. Data from 2001 and 2002 was analysed. Hospitals performing <400 PTCAs per year were classified as low-volume. A case-control analysis (propensity score) compared in-hospital mortality in low- and high-volume centres. A total of 37 848 angioplasty procedures were performed in 44 centres during the study period; 24.7% were performed in low-volume centres. A non-statistically significant trend towards reduced in-hospital mortality was noted in high-volume centres as opposed to low-volume centres: 2.01 vs. 2.42%, P = 0.057. In-hospital mortality rates were significantly different in the sub-group of emergency procedures: 6.75% in high- vs. 8.54% in low-volume centres, P = 0.028. No difference was noted between low- and high-volume centres in non-emergency procedures (0.62 vs. 0.62%, P = 0.99). CONCLUSION: In the era of modern stenting, a clear inverse relationship exists between hospital PTCA volume and in-hospital mortality after emergency procedures. Tolerance of low-volume thresholds for angioplasty centres with the purpose of providing primary PTCA in AMI should not be recommended, even in underserved areas. 相似文献
17.
Tannenbaum C Brouillette J Korner-Bitensky N Dumoulin C Corcos J Tu le M Lemieux MC Ouellet S Valiquette L 《Journal of the American Geriatrics Society》2008,56(3):542-547
OBJECTIVES: To report on the content development, construct validity, and reliability testing of the Geriatric Self-Efficacy Index for Urinary Incontinence (GSE-UI).
DESIGN: Prospective cohort study.
SETTING: Six UI outpatient clinics in Quebec, Canada.
PARTICIPANTS: Community-dwelling incontinent men and women aged 65 and older.
MEASUREMENTS: Thirty-eight items were generated using a literature search and interdisciplinary panel of experts. Item reduction was achieved through field-testing with 75 older men and women with UI attending an information session. The final 20-item draft, measuring older adults' level of confidence in preventing urine loss, was administered to a new group of consecutive patients 1 week before and at the time of their first visit to the UI clinic to enable evaluation of test–retest reliability. A 3-day voiding diary, quantifying the frequency of UI, and the Incontinence Quality of Life questionnaire were used to test construct validity.
RESULTS: One hundred sixteen of 300 eligible patients (39%) participated (mean age±standard deviation 74±6, range 65–87). The GSE-UI items showed normal distributions and no ceiling effects. Self-efficacy scores ranged from 16 to 193 (mean 104±41, possible range 0–200) and correlated positively with quality of life scores ( r =0.7, P <.001) and negatively with UI severity ( r =−0.4, P <.001). Internal consistency for the GSE-UI was 0.94 (Cronbach alpha). Initial test–retest reliability of the 20 items using intraclass correlations ranged from 0.50 to 0.86.
CONCLUSION: The GSE-UI will enable measurement of whether a person's confidence in their ability to prevent urine loss is an important mechanism contributing to improvements in UI. 相似文献
DESIGN: Prospective cohort study.
SETTING: Six UI outpatient clinics in Quebec, Canada.
PARTICIPANTS: Community-dwelling incontinent men and women aged 65 and older.
MEASUREMENTS: Thirty-eight items were generated using a literature search and interdisciplinary panel of experts. Item reduction was achieved through field-testing with 75 older men and women with UI attending an information session. The final 20-item draft, measuring older adults' level of confidence in preventing urine loss, was administered to a new group of consecutive patients 1 week before and at the time of their first visit to the UI clinic to enable evaluation of test–retest reliability. A 3-day voiding diary, quantifying the frequency of UI, and the Incontinence Quality of Life questionnaire were used to test construct validity.
RESULTS: One hundred sixteen of 300 eligible patients (39%) participated (mean age±standard deviation 74±6, range 65–87). The GSE-UI items showed normal distributions and no ceiling effects. Self-efficacy scores ranged from 16 to 193 (mean 104±41, possible range 0–200) and correlated positively with quality of life scores ( r =0.7, P <.001) and negatively with UI severity ( r =−0.4, P <.001). Internal consistency for the GSE-UI was 0.94 (Cronbach alpha). Initial test–retest reliability of the 20 items using intraclass correlations ranged from 0.50 to 0.86.
CONCLUSION: The GSE-UI will enable measurement of whether a person's confidence in their ability to prevent urine loss is an important mechanism contributing to improvements in UI. 相似文献
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Szathmary S Hegyi E Amoureux MC Rajapakse N Chicorka L Szalai G Reszegi K Derbyshire Z Paluh J Dodson B Grandics P 《Blood purification》2004,22(5):409-415
Bacterial pyrogens, capable of penetrating dialyzer membranes, are responsible for a systemic inflammatory reaction in hemodialysis patients. Dialyzer reuse, involving rinsing of the dialyzer with pyrogen-containing water, may exacerbate this situation. Studies of the mechanism of action of endotoxin suggest that it irreversibly damages the vascular endothelium. The novel endotoxin removal method described here, is based on affinity-binding of endotoxin by the adsorbent ClarEtox, a USP Class VI-certified resin that is the active component of the medical device DialGuard. Under standard hemodialysis operating conditions, challenge of DialGuard with Pseudomonas maltophilia supernatant-spiked dialysate, containing 35-193 EU/ml endotoxin, resulted in endotoxin levels below 0.05 EU/ml in the treated dialysate. DialGuard was able to decrease endotoxin concentrations in the dialysate from a range of 2.39-8.49 to <0.005 EU/ml. DialGuard supports high fluid velocities at low back pressures and can be sanitized using the heat sanitization cycle of hemodialysis machines. DialGuard offers a simple, user-friendly way to reduce the concentration of endotoxin in dialysate and water for dialysis at a low cost. 相似文献