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171.
Ko YJ Devi GR London CA Kayas A Reddy MT Iversen PL Bubley GJ Balk SP 《The Journal of urology》2004,172(3):1140-1144
PURPOSE: Androgen receptor (AR) has a pivotal role in the growth and proliferation of prostate cancer (PCa). Even in advanced stages of PCa AR continues to be expressed and appears to be functional. Since the mechanisms of AR activation in androgen independent PCa have yet to be clearly defined, the decrease in AR protein by antisense compounds is an attractive therapeutic option. In this study we evaluated a novel antisense phosphorodiamidate morpholino oligomer (PMO) targeting the translational start site of AR mRNA in vitro and in vivo in a PCa xenograft and murine prostate. MATERIALS AND METHODS: AR antisense PMOs targeting the AR initiation AUG were tested in vitro and in LNCaP cells, and in vivo in LAPC-4 xenografts and normal mouse prostate. Effects on AR protein and PSA expression were assessed. RESULTS: AR antisense PMOs specifically down-regulated AR protein levels in a plasmid based screening system and also decreased endogenous AR levels in androgen responsive LNCaP cells in culture compared to control nonspecific PMOs. Pretreatment and posttreatment biopsies in the LAPC-4 xenograft model demonstrated that the antisense AR PMO administered intraperitoneally specifically decreased AR protein levels and serum PSA. Analysis of tissue distribution of the AR PMO by high performance liquid chromatography based methodology showed significant PMO levels in tumor tissue and mouse prostate, and there was a dose dependent decrease in AR protein levels in murine AR antisense PMO treated mouse prostates. CONCLUSIONS: An AR antisense PMO with unique chemical properties administered once daily can decrease AR protein levels and PSA in vivo. The reduction of AR protein with an antisense PMO may be an effective method of interfering with AR mediated growth in advanced human PCa. 相似文献
172.
Brinker MR Gugenheim JJ O'Connor DP London JC 《American journal of orthopedics (Belle Mead, N.J.)》2004,33(10):489-493
Ideally, acquired femoral malrotation as a complication of intramedullary nailing of a femoral shaft fracture should be identified and corrected early in the course of treatment. In this report, we present a previously undescribed precise surgical technique for acutely correcting an acquired femoral malrotation deformity 20 days after fixation of a femoral shaft fracture with a statically locked intramedullary nail. An llizarov external fixator was used intraoperatively to correct a 27 degree femoral malrotation deformity in a 19-year-old man. 相似文献
173.
Whelan JS McTiernan A Kakouri E Kilby A;London Bone Soft Tissue Tumour Service 《Pediatric blood & cancer》2004,43(3):237-242
BACKGROUND: Failure of first line therapy for the Ewing's family of tumours (EFT) is associated with a very poor outlook. Studies of second line chemotherapy are therefore necessary to identify active agents and drug combinations. Cisplatin-based therapy is frequently used in these circumstances but there are few studies to clearly define activity and toxicity. This report details outcome in a cohort of patients with poor risk EFT treated with a carboplatin-based combination. PROCEDURE: Between 1990 and 1998, 23 males and 16 females aged between 6 and 48 years (median 23) with relapsed or refractory EFT were treated with carboplatin-based chemotherapy. Previous chemotherapy had included ifosfamide and doxorubicin in all but two patients. Twenty patients were treated at the time of recurrence, and 19 after a poor response to initial chemotherapy. Treatment comprised of carboplatin to give an area under the plasma carboplatin concentration versus time curve of (AUC) 6 mg/ml, etoposide 120 mg/m2 for 3 days, and cyclophosphamide 500-750 mg/m2 for 2 days, repeated every 21 days. RESULTS: A total of 105 cycles were given, median 2 per patient (range 1-5). Overall response was 26%, with one complete response and nine partial responses. Median time to progression was 10 weeks (range 2-54). Haematological toxicity was severe requiring dose reductions in 53% of patients. Six patients proceeded to high dose consolidation treatment with bone marrow or peripheral stem cell rescue. CONCLUSIONS: This combination results in a substantial response rate in previously treated patients but with significant toxicity. Responses are, however, relatively short. 相似文献
174.
O'Brien MM Shroyer AL Moritz TE London MJ Grunwald GK Villanueva CB Thottapurathu LG MaWhinney S Marshall G McCarthy M Henderson WG Sethi GK Grover FL Hammermeister KE;VA Cooperative Study Group on Processes Structures Outcomes of Care in Cardiac Surgery 《Medical care》2004,42(1):59-70
BACKGROUND: Information is limited regarding the effects of processes of care on cardiac surgical outcomes. Correspondingly, many recommended cardiac surgical processes of care are derived from animal experiments or clinical judgment. This report from the VA Cooperative Study in Health Services, "Processes, Structures, and Outcomes of Cardiac Surgery," focuses on the relationships between 3 process groups (preoperative evaluation, intraoperative care, and supervision by senior physicians) and a composite outcome, perioperative mortality and morbidity. METHODS: Data on 734 risk, process, and structure variables were collected prospectively on 3,988 patients who underwent coronary artery bypass grafting at 14 VA medical centers between 1992 and 1996. Data reduction was accomplished by examining data completeness and variation across sites and surgeon, using previously published data and clinical judgment. We then applied multivariable logistic regression to the 39 remaining processes of care to determine which were related to the composite outcome after adjusting for 17 patient-related risk factors and controlling for intraoperative complications. RESULTS: Our first analysis showed several measures of operative duration, the use of inotropic agents, transesophageal echo, lowest systemic temperature, and hemoconcentration/ultrafiltration, to be powerful predictors of the composite outcome. Because the use of inotropic agents and operative duration may be related to an intermediate outcome (eg, intraoperative complications), we performed a second analysis omitting these processes. The use of intraoperative transesophageal echo and hemoconcentration/ultrafiltration remained significantly associated with an increased risk of an event (odds ratios 1.60 and 1.36, respectively). CONCLUSIONS: Our results viewed in the context of past studies suggest the possibility that inotropic use, TEE, and hemoconcentration/ultrafiltration may have adverse effects on operative outcome. Further evaluation of these processes of care using observational data, as well as randomized trials when feasible, would be of interest. 相似文献
175.
PURPOSE: Information on indoor allergen exposures among non-Western populations, which have lower prevalence of atopic illness, is scant. We examined whether exposures to common indoor allergens were associated with doctor-diagnosed asthma and asthma-related symptoms among Chinese adolescents. METHODS: A cross-sectional study of 4,185 ninth grade students was conducted at 22 randomly selected schools in Wuhan, China. Information on respiratory health and exposures to indoor allergens was obtained by a self-administered questionnaire completed in class. RESULTS: Having animals currently was associated with persistent cough [prevalence odds ratio (POR)=1.54, 95% confidence interval (CI ): 1.21-2.11] and wheeze (POR=1.41, 95% CI: 1.03-1.94). Early-life exposure to animals was also associated with doctor-diagnosed asthma (POR=1.95, 95% CI: 1.35-2.82). Associations with respiratory symptoms strengthened with higher levels of exposure and for exposure in both early childhood and in adolescence. Exposure to cockroaches and having mold/water damage in the home contributed especially to wheezing (POR=2.03, 95% CI: 1.41-2.90 for cockroaches; POR=2.49, 95% CI: 1.82-3.40 for mold/water damage). CONCLUSIONS: Indoor allergen exposures were positively associated with asthma diagnosis and persistent respiratory symptoms among Chinese adolescents. Neither early-life nor current exposure to animals was protective for asthma or asthma-related symptoms. 相似文献
176.
In vitro and in vivo characterization of a novel naphthylamide ATP-sensitive K+ channel opener, A-151892 总被引:1,自引:0,他引:1
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Gopalakrishnan M Buckner SA Shieh CC Fey T Fabiyi A Whiteaker KL Davis-Taber R Milicic I Daza AV Scott VE Castle NA Printzenhoff D London B Turner SC Carroll WA Sullivan JP Coghlan MJ Brune ME 《British journal of pharmacology》2004,143(1):81-90
1. Openers of ATP-sensitive K(+) channels are of interest in several therapeutic indications including overactive bladder and other lower urinary tract disorders. This study reports on the in vitro and in vivo characterization of a structurally novel naphthylamide N-[2-(2,2,2-trifluoro-1-hydroxy-1-trifluoromethyl-ethyl)-naphthalen-1-yl]-acetamide (A-151892), as an opener of the ATP-sensitive potassium channels. 2. A-151892 was found to be a potent and efficacious potassium channel opener (KCO) as assessed by glibenclamide-sensitive whole-cell current and fluorescence-based membrane potential responses (-log EC(50)=7.63) in guinea-pig bladder smooth muscle cells. 3. Evidence for direct interaction with KCO binding sites was derived from displacement of binding of the 1,4-dihydropyridine opener [(125)I]A-312110. A-151892 displaced [(125)I]A-312110 binding to bladder membranes with a -log Ki value of 7.45, but lacked affinity against over 70 neurotransmitter receptor and ion channel binding sites. 4. In pig bladder strips, A-151892 suppressed phasic, carbachol-evoked and electrical field stimulus-evoked contractility in a glibenclamide-reversible manner with -log IC(50) values of 8.07, 7.33 and 7.02 respectively, comparable to that of the potencies of the prototypical cyanoguanidine KCO, P1075. The potencies to suppress contractions in thoracic aorta (-log IC(50)=7.81) and portal vein (-log IC(50)=7.98) were not substantially different from those observed for suppression of phasic contractility of the bladder smooth muscle. 5. In vivo, A-151892 was found to potently suppress unstable bladder contractions in obstructed models of unstable contractions in both pigs and rats with pED(35%) values of 8.05 and 7.43, respectively. 6. These results demonstrate that naphthylamide analogs exemplified by A-151892 are novel K(ATP) channel openers and may serve as chemotypes to exploit additional analogs with potential for the treatment of overactive bladder and lower urinary tract symptoms. 相似文献
177.
Attenuation of cue-induced cigarette craving and anterior cingulate cortex activation in bupropion-treated smokers: a preliminary study 总被引:10,自引:0,他引:10
Brody AL Mandelkern MA Lee G Smith E Sadeghi M Saxena S Jarvik ME London ED 《Psychiatry research》2004,130(3):269-281
In untreated smokers, exposure to cigarette-related cues increases both the intensity of cigarette craving and relative glucose metabolism of the perigenual/ventral anterior cingulate cortex (ACC). Given that treatment with bupropion HCl reduces overall cigarette craving levels in nicotine dependent subjects, we performed a preliminary study of smokers to determine if bupropion HCl treatment attenuates cue-induced cigarette craving and associated brain metabolic activation. Thirty-seven, otherwise healthy smokers (20 untreated and 17 who had received open-label treatment with bupropion HCl) underwent two (18)F-fluorodeoxyglucose positron emission tomography scanning sessions in randomized order--one when presented with neutral cues and the other when presented with cigarette-related cues. Bupropion-treated smokers had smaller cigarette cue-induced increases in craving scores on the Urge to Smoke (UTS) Scale and less activation of perigenual/ventral ACC metabolism from the neutral to the cigarette cue scan than untreated smokers. Thus, in addition to its known effects on spontaneous cigarette craving and withdrawal symptoms, bupropion HCl diminishes cue-induced cigarette craving and appears to attenuate cigarette cue-induced ACC activation. These results are consistent with the known effects of bupropion HCl, including its enhancement of catecholaminergic neurotransmission. 相似文献
178.
Impaired performance in a test of decision-making by opiate-dependent tobacco smokers 总被引:4,自引:0,他引:4
This study tested whether opiate dependence, tobacco smoking, or their combination accompanied impaired performance on the gambling task (GT), which tests decision-making. GT previously detected impairments in patients with lesions of the ventromedial prefrontal cortex and in substance abusers. Four groups were matched on demographic characteristics and intelligence: methadone-maintained smokers (n = 9) and nonsmokers (n = 9), and control (i.e., not opiate-dependent) smokers (n = 9) and nonsmokers (n = 10). The Wisconsin Card Sorting Task (WCST) was administered to test whether differences in GT performance reflected generalized deficits in prefrontal cortical function. While there were no significant group differences on the WCST, groups differed significantly on GT performance (F(3,31) = 2.95, P = 0.048), controlling for depressive symptom ratings and childhood attention deficit hyperactivity disorder. Methadone-maintained smokers (but not nonsmokers) performed more poorly than either of the two control groups (P = 0.007 versus smokers; P = 0.024 versus nonsmokers). In a planned analysis of methadone-maintained subjects, smokers scored more poorly on GT than nonsmokers (F(1,18) = 5.64, P = 0.032) and had more treatment failures (67% heroin use during the last 30 days versus 20%). The findings suggest that among opiate-dependent individuals, tobacco smoking may be a marker for a more severe form of substance abuse disorder, reflecting impaired decision-making, as modeled by GT. 相似文献
179.
180.
Oral misoprostol before office endometrial biopsy 总被引:1,自引:0,他引:1
Perrone JF Caldito G Mailhes JB Tucker AN Ford WR London SN 《Obstetrics and gynecology》2002,99(3):439-444
OBJECTIVE: To evaluate oral misoprostol use before office endometrial biopsy. METHODS: Forty-two nonpregnant women aged 35-77 years were randomized to a prospective, double-blind study to receive either 400 microg oral misoprostol or placebo 3 hours before office endometrial biopsy. Misoprostol effects were assessed by 1) cervical resistance, 2) ease of performing the endometrial biopsy, 3) success rate of obtaining an endometrial biopsy, 4) pain intensity associated with the endometrial biopsy, and 5) adverse clinical side effects. RESULTS: Patients in the misoprostol group experienced significantly (P <.01) more pain associated with the endometrial biopsy. The observed power to detect this difference in misoprostol-placebo comparison using the Wilcoxon rank sum test at 0.05 level of significance is 89%. In addition, significantly (P <.05) more patients had the adverse side effect of uterine cramping at 1.5 hours after medication ingestion in the misoprostol group. The observed power to detect this difference is 98%. There were no differences between the misoprostol and placebo groups in cervical resistance, ease of performing the biopsy, success rate for obtaining an endometrial biopsy, or adverse side effects at 3 hours post medication ingestion. CONCLUSION: Oral misoprostol 400 microg caused more uterine cramping and pain in nonpregnant women undergoing office endometrial biopsy when given 3 hours before biopsy attempt. No other cervical effects were noted. 相似文献