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41.
Thomas Viel Parisa Monfared Sonja Schelhaas Inga B Fricke Michael T Kuhlmann Cornel Fraefel Andreas H Jacobs 《Molecular therapy》2013,21(3):570-579
Despite treatments combining surgery, radiation-, and chemotherapy, patients affected by glioblastoma (GBM) have a limited prognosis. Addition of temozolomide (TMZ) to radiation therapy is the standard therapy in clinical application, but effectiveness of TMZ is limited by the tumor''s overexpression of the DNA repair protein O6-methylguanine-DNA methyltransferase (MGMT). The goal of this study was to use the highly specific and efficient RNA interference (RNAi) pathway to modulate MGMT expression to increase TMZ efficiency in chemotherapy resistant GBM. Using lentiviral-based anti-MGMT small hairpin RNA (shRNA) technology we observed a specific inhibition of the MGMT expression in GBM cell lines as well as in subcutaneous tumors. Tumor growth inhibition was observed following TMZ treatment of xenografts with low MGMT expression in contrast to xenografts with high MGMT expression. Bioluminescence imaging (BLI) measurements indicated that luciferase and shRNA-expressing lentiviruses were able to efficiently transduce the GBM xenografts in vivo. Treatment combining injection of a lentivirus expressing an anti-MGMT shRNA and TMZ induced a reduction of the size of the tumors, in contrast with treatment combining the lentivirus expressing the control shRNA and TMZ. Our data suggest that anti-MGMT shRNA therapy could be used in combination with TMZ chemotherapy in order to improve the treatment of resistant GBM. 相似文献
42.
Torben H?iland Hansen Mette Laursen Erik Christensen Helge Worning 《Journal of gastrointestinal cancer》1995,18(3):235-239
Summary The relationship between chronic pancreatitis (CP) and extrapancreatic cancer has been debated in the recent years. In prospective
studies, it has been found that pancreatic cancer develops in 0–5% of patients with chronic pancreatitis. Many papers describe
an increased relative risk for developing extrapancreatic cancer in patients suffering from chronic pancreatitis. In this
study including 181 patients with CP, we found 14 patients with extrapancreatic cancer (three of these had two different types
of cancer). No patient had pancreatic cancer. It was found that the respiratory airways and upper gastrointestinal tract were
the dominating locations (five and four cases, respectively), but also genital and hemolymphopoietic cancers were represented
(four and two cases, respectively). Two patients had metastatic cancer with unknown primary tumor. The patients with cancer
tended to be older than those without cancer. The patients with CP had a 2.43 times greater risk of developing cancer than
the general Danish population (age and sex standardized comparison). The relatively large number of cancers in the upper gastrointestinal
tract and respiratory airways suggest that tobacco and alcohol may be responsible, as these organs have the highest exposure
to these compounds, which are well known carcinogens. 相似文献
43.
Emily Kroshus Christine M. Baugh Daniel H. Daneshvar Julie M. Stamm R. Mark Laursen S. Bryn Austin 《Journal of Athletic Training》2015,50(9):944-951
Context
Anecdotal and qualitative evidence has suggested that some clinicians face pressure from coaches and other personnel in the athletic environment to prematurely return athletes to participation after a concussion. This type of pressure potentially can result in compromised patient care.Objective
To quantify the extent to which clinicians in the collegiate sports medicine environment experience pressure when caring for concussed athletes and whether this pressure varies by the supervisory structure of the institution''s sports medicine department, the clinician''s sex, and other factors.Design
Cross-sectional study.Setting
Web-based survey of National College Athletic Association member institutions.Patients or Other Participants
A total of 789 athletic trainers and 111 team physicians from 530 institutions.Main Outcome Measure(s)
We asked participants whether they had experienced pressure from 3 stakeholder populations (other clinicians, coaches, athletes) to prematurely return athletes to participation after a concussion. Modifying variables that we assessed were the position (athletic trainer, physician) and sex of the clinicians, the supervisory structure of their institutions'' sports medicine departments, and the division of competition in which their institutions participate.Results
We observed that 64.4% (n = 580) of responding clinicians reported having experienced pressure from athletes to prematurely clear them to return to participation after a concussion, and 53.7% (n = 483) reported having experienced this pressure from coaches. Only 6.6% (n = 59) reported having experienced pressure from other clinicians to prematurely clear an athlete to return to participation after a concussion. Clinicians reported greater pressure from coaches when their departments were under the supervisory purview of the athletic department rather than a medical institution. Female clinicians reported greater pressure from coaches than male clinicians did.Conclusions
Most clinicians reported experiencing pressure to prematurely return athletes to participation after a concussion. Identifying factors that are associated with variability in pressure on clinicians during concussion recovery can inform potential future strategies to reduce these pressures.Key Words: conflict of interest, organizational structure, sex, collegeKey Points
- More than half of sports medicine clinicians had experienced pressure from coaches and athletes to return athletes to participation prematurely after a concussion.
- Clinicians experienced greater pressure from coaches at schools where the sports medicine department reported to the athletic department than at schools where the sports medicine department reported to an independent medical institution.
- Female clinicians experienced greater pressure from coaches than male clinicians experienced.
- More research is needed to determine how pressure affects clinical practice and whether pressure on clinicians affects return-to-participation decisions.
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46.
André M Odenholt I Schwan A Axelsson I Eriksson M Hoffman M Mölstad S Runehagen A Lundborg CS Wahlström R;Swedish Study Group on Antibiotic Use 《Scandinavian journal of infectious diseases》2002,34(12):880-886
A diagnosis/antibiotic prescribing study was performed in 5 counties in Sweden for 1 week in November 2000. As part of this study, the characteristics and clinical management of patients with upper respiratory tract infections (n = 2899) in primary care were analyzed. Almost half of the patients were aged < 15 y and one-fifth of the patients consulted out of hours. Of all patients seeking primary care for upper respiratory tract infections, 56.0% were prescribed an antibiotic. Almost all patients who were given the diagnoses streptococcal tonsillitis, acute otitis media or acute sinusitis were prescribed antibiotics, compared to 10% of patients with common cold or acute pharyngitis. The most frequently prescribed antibiotic was penicillin V (79.2%) and this was even more pronounced out of hours, when the diagnoses otitis media and streptococcal tonsillitis were more frequently used. In patients with common cold and acute pharyngitis, the percentage who received antibiotics increased with increasing length of symptoms and increasing CRP levels. In patients with acute pharyngitis or streptococcal tonsillitis, antibiotics were prescribed less frequently provided streptococcal tests were performed. The management of patients with upper respiratory tract infections in general practice seems to be in good agreement with current Swedish guidelines. However, the study indicates some areas for improvement. The diagnosis of acute sinusitis seems to have been overestimated and used only to justify antibiotic treatment. 相似文献
47.
Peter I Shearman AM Zucker DR Schmid CH Demissie S Cupples LA Larson MG Vasan RS D'Agostino RB Karas RH Mendelsohn ME Housman DE Levy D 《Journal of hypertension》2005,23(12):2193-2200
OBJECTIVE: To examine the association between variation in estrogen-related genes and cross-sectional and longitudinal blood pressure in men and women. DESIGN: In 1780 unrelated members of the community-based Framingham Heart Study offspring cohort, systolic blood pressure and diastolic blood pressure were measured over a total of six examination cycles encompassing 24 years of follow-up. Multivariate regression analyses were used to assess the relation between untreated cross-sectional and longitudinal blood pressure and polymorphisms at the estrogen receptor-alpha (ESR1), estrogen receptor-beta (ESR2), aromatase (CYP19A1), and nuclear receptor coactivator 1 (NCOA1) genes after adjustment for common risk factors. RESULTS: In men, systolic blood pressure and pulse pressure (systolic blood pressure minus diastolic blood pressure) were associated with two polymorphisms in ESR1, while pulse pressure was also associated with variations in NCOA1 and CYP19A1. Polymorphisms in ESR1, CYP19A1, and NCOA1 were associated with diastolic blood pressure in women. CONCLUSIONS: Although the underlying relations between genes involved in estrogen action and hypertension remain to be completely understood, our findings provide suggestive evidence of gender-specific contributions of estrogen-related genes to blood pressure variation. As no correction for multiple testing was performed in the analyses, we view these results as suggestive and not definitive. Further studies are warranted to confirm these results using a comprehensive set of polymorphisms in order to shed more light on the involvement of estrogen in blood pressure regulation. 相似文献
48.
Langhorst J Anthonisen IB Steder-Neukamm U Lüdtke R Spahn G Michalsen A Dobos GJ 《Inflammatory bowel diseases》2005,11(3):287-295
OBJECTIVES: Previous studies have suggested that inflammatory bowel disease (IBD) patients rank high among users of complementary and alternative medicine (CAM). To further elucidate this phenomenon, we sent questionnaires to a large sample of IBD patients in Germany to determine the patterns and predictors of their CAM use. METHODS: Pretested 73-item questionnaires were mailed to a randomly selected representative sample of 1000 IBD patients from the approximately 16,000 members and associates of the German Crohn's and Colitis Association. Predictors of CAM use were evaluated by logistic regression models. RESULTS: Completed questionnaires were returned by 684 patients (female patients, 61.4%; Crohn's disease patients, 58.3%; ulcerative colitis patients, 38.2%). Of the 671 adult respondents, 344 (51.3%) had experience with CAM, and significantly more of the ulcerative colitis patients (59.8%) than the Crohn's disease patients (48.3%) had experience with CAM. There was no difference by gender. Homeopathy (52.9%) and herbal medicine (43.6%) were the most commonly used types of CAM. The most frequent personal reasons for CAM use were the search for an "optimum treatment" (78.9%) and the wish to stop taking steroids (63.8%). Using logistic regression, we found that total cortisone intake (P = 0.0077), but not duration of disease, was a strong predictor of CAM use. Other predictors were experience with psychosomatic and psychotherapeutic support (P = 0.0029), relaxation techniques (P = 0.0284), an academic education (P = 0.0173), a diet utilizing whole grains (P = 0.0123), and a normal body weight (P = 0.0215). Although 80% of patients indicated that they were interested in using CAM in the future, only 24.7% felt sufficiently informed about it. CONCLUSIONS: More than 50% of a large group of German IBD patients had used CAM. Prolonged or intensive steroid treatment, an academic education, active ways of coping, and a health-conscious life-style are associated with CAM use. Given the potential side effects and interactions, the treating physician should focus on thorough information about the benefits and limitations of conventional and complementary treatment options, especially for IBD patients who have received prolonged or intensive steroid treatment. 相似文献
49.
Omeprazole 20 mg three days a week and 10 mg daily in prevention of duodenal ulcer relapse. Double-blind comparative trial 总被引:2,自引:0,他引:2
K Lauritsen B N Andersen L S Laursen J Hansen T Havelund J Eriksen J F Rehfeld J Kjaergaard J Rask-Madsen 《Gastroenterology》1991,100(3):663-669
In a double-blind, parallel-group clinical trial of 195 patients with duodenal ulcers who after a short-term study had relief of pain and healed ulcers proved endoscopically, 65 were randomized to receive 20 mg omeprazole 3 days a week (once in the morning from Friday to Sunday), 64 to receive 10 mg omeprazole once daily in the morning, and 66 to receive placebo for up to 6 months. The patients underwent repeat endoscopy with biopsy of the gastric fundic mucosa (qualitative assessment of argyrophilic cell population), assessment of symptoms, and laboratory screening with measurement of basal serum gastrin concentrations at 3 and 6 months or more often if indicated by recurrence of symptoms. At 3 months, endoscopically proved ulcer relapse occurred in 16% receiving 20 mg omeprazole 3 days a week; 21% receiving 10 mg omeprazole daily; and 50% receiving placebo. At 6 months, corresponding rates were 23%, 27%, and 67% with 95% confidence intervals of difference between the placebo group and omeprazole groups of 28%-60% and 24%-56% (P less than 0.00001), respectively, and between omeprazole groups of -19%-11% (NS). No major clinical or laboratory side effects were noted. Thus both omeprazole regimens are effective and safe in preventing duodenal ulcer relapse. 相似文献
50.