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971.
Tryptophan depletion alters the decision-making of healthy volunteers through altered processing of reward cues. 总被引:7,自引:0,他引:7
Robert D Rogers Elizabeth M Tunbridge Zubin Bhagwagar Wayne C Drevets Barbara J Sahakian Cameron S Carter 《Neuropsychopharmacology》2003,28(1):153-162
While accumulating evidence suggests that effective real-life decision-making depends upon the functioning of the orbitofrontal cortex, much less is known about the involvement of the monoamine neurotransmitter systems and, in particular, serotonin. In the present study, we explored the impact of depleting the serotonin precursor, tryptophan, on human decision-making. Eighteen healthy volunteers consumed an amino-acid drink containing tryptophan and 18 healthy volunteers consumed an amino-acid drink without tryptophan, before choosing between simultaneously presented gambles, differing in the magnitude of expected gains (ie reward), the magnitude of expected losses (ie punishment), and the probabilities with which these outcomes were delivered. Volunteers also chose between gambles probing identified non-nomative biases in human decision-making, namely, risk-aversion when choosing between gains and risk-seeking when choosing between losses. Tryptophan-depleted volunteers showed reduced discrimination between magnitudes of expected gains associated with different choices. There was little evidence that tryptophan depletion was associated with altered discrimination between the magnitudes of expected losses, or altered discrimination between the relative probabilities with which these positive or negative outcomes were delivered. Risk-averse and risk-seeking biases were also unchanged. These results suggest that serotonin mediates decision-making in healthy volunteers by modulating the processing of reward cues, perhaps represented within the orbitofrontal cortex. It is possible that such a change in the cognition mediating human choice is one mechanism associated with the onset and maintenance of anhedonia and lowered mood in psychiatric illness. 相似文献
972.
Nella Bieszk Rosalie Patel Andrea Heaberlin Ken Wlasuk Barbara Zarowitz 《American journal of health-system pharmacy》2003,60(4):360-366
The utility of pharmacy claims data in detecting improper medication use, medication changes, and formulary adherence was assessed. Pharmacists provided six months of pharmacy claims data to primary care physicians for patients on the day of their scheduled clinic appointments. Similar data, not supplied to physicians, were generated for a matched population of patients on the day of their scheduled clinic appointments. A blinded pharmacist abstracter reviewed dictated office notes for both control and treatment groups. Medication adherence and medication changes were assessed by the abstracter as well as the difference in total medication costs for each of the groups before and after the pharmacy claims data were supplied. Surveys were distributed to physicians to determine whether pharmaceutical care was improved by the pharmacy claims data. In the treatment group, physicians detected medication nonadherence in 30.5% of their patients, while the abstracter noted nonadherence in 58.1% of patients. Physicians failed to detect any nonadherence in the control group, but the abstractor detected nonadherence in 57.1% of these patients. Changes in medication regimens occurred more often in the treatment group (p < 0.001). The mean percentage of patients switched to formulary agents significantly differed between the treatment and control groups (27.7% versus 0.0%, respectively) (p < 0.001). There were no differences in median drug costs for either group before or after the pharmacy claims data were provided. Provision of pharmacy claims data to physicians helped them detect medication nonadherence, evaluate therapeutic duplication or omissions, increase formulary use, and reduce the time required to obtain an accurate medication history. 相似文献
973.
Matthew A Silva Gary R Tataronis Barbara Maas 《American journal of health-system pharmacy》2003,60(9):911-915
The use of personal digital assistants (PDAs) to document pharmacist cognitive services and estimate potential reimbursement was studied. Between September 2001 and February 2002, four pharmacy residents and four clinical pharmacists used PDAs for documenting cognitive services. Interventions recorded on paper during the same six-month period one year earlier were reviewed for comparison. Potential reimbursement for these services was calculated by linking current procedural terminology codes and charges to the electronically documented services. Over the six-month study period, pharmacists recorded 7319 interventions with PDAs, compared with 5028 documented on paper during the earlier six-month period. Potential claims for pharmacists' cognitive services documented with PDAs amounted to more than $1 million in the six months, assuming a 100% reimbursement rate. PDAs provide a simple, efficient paperless system for documenting pharmacists' clinical services and generating reimbursement claims. 相似文献
974.
Pseudoaneurysm of the medial inferior genicular artery following anterior cruciate ligament reconstruction 总被引:1,自引:0,他引:1
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Evans JD de Boer MT Mayor P Rees D Guy AJ 《Annals of the Royal College of Surgeons of England》2000,82(3):182-184
Pseudoaneurysm is a rare complication of surgery or trauma around the knee. A 30-year-old man presented 10 days following anterior cruciate ligament repair with a 2 cm pulsatile swelling on the medial side of the knee. Angiography demonstrated a pseudoaneurysm of the medial inferior genicular artery. Surgical exploration and ligation of the feeding vessel to the aneurysm was performed and the patient made a full recovery. Vascular injury must be suspected in patients presenting with a haemarthrosis or pulsatile swelling following surgery on the knee. 相似文献
975.
Anthony T C Chan Qian Tao Keith D Robertson Ian W Flinn Risa B Mann Barbara Klencke Wing Hong Kwan Thomas Wai-Tong Leung Philip J Johnson Richard F Ambinder 《Journal of clinical oncology》2004,22(8):1373-1381
PURPOSE: To determine whether therapy with a DNA methyltransferase inhibitor is effective in achieving demethylation and gene re-expression in tumor DNA in patients. METHODS: Biopsy specimens were obtained from patients with Epstein-Barr virus-associated tumors, enrolled on a clinical trial of 5-azacitidine, within 72 hours of the conclusion of the last infusion of the first cycle of therapy, and compared to pretreatment specimens. Methylation-specific polymerase chain reaction, bisulfite genomic sequencing, and immunohistochemistry were used to assess demethylation and gene re-expression. RESULTS: Substantial degrees of demethylation were detected in all latent and lytic Epstein-Barr virus promoters examined. Immunohistochemistry suggested activation of a previously silent viral antigen expression in one instance. CONCLUSION: Pharmacologic reversal of dense CpG methylation in tumor tissue can be achieved in patients. 相似文献
976.
Raphael P Viscidi Mark Schiffman Allan Hildesheim Rolando Herrero Philip E Castle Maria C Bratti Ana Cecilia Rodriguez Mark E Sherman Sophia Wang Barbara Clayman Robert D Burk 《Cancer epidemiology, biomarkers & prevention》2004,13(2):324-327
Whether antibodies to human papillomavirus (HPV) capsids, elicited by natural infection, are protective is unknown. This question was addressed in a population-based cohort of 7046 women in Costa Rica by examining the association between baseline seroreactivity to HPV-16, HPV-18, or HPV-31 virus-like particles and the risk of subsequent HPV infection at a follow-up visit 5-7 years after enrollment. Seropositivity to HPV-16, HPV-18, or HPV-31 was not associated with a statistically significant decreased risk of infection with the homologous HPV type [relative risk (RR) and [95% confidence interval (CI)], 0.74 (0.45-1.2), 1.5 (0.83-2.7), and 0.94 (0.48-1.8), respectively]. Seropositivity to HPV-16 or HPV-31 was not associated with a decreased risk of infection with HPV-16 or its genetically related types [RR (95% CI), 0.82 (0.61-1.1) and 0.93 (0.68-1.2), respectively]. Seropositivity to HPV-18 was not associated with a decreased risk of infection with HPV-18 or its genetically related types (RR 1.3; 95% CI 1.0-1.8). Thus, we did not observe immunity, although a protective effect from natural infection cannot be excluded because of the limits of available assays and study designs. 相似文献
977.
Edgardo Rivera Vicente Valero Deborah Francis Aviva G Asnis Larry J Schaaf Barbara Duncan Gabriel N Hortobagyi 《Clinical cancer research》2004,10(6):1943-1948
PURPOSE: We conducted a pilot study assessing the effects of the selective estrogen receptor modulator, tamoxifen, on the pharmacokinetics, pharmacodynamics, and safety of the steroidal, irreversible aromatase inhibitor (AI), exemestane, when the two were coadministered in postmenopausal women with metastatic breast cancer. EXPERIMENTAL DESIGN: Patients with documented or unknown hormone receptor sensitivity were eligible. Patients received oral exemestane at 25-mg once daily. Starting day 15, oral tamoxifen at 20-mg once daily, was added. We measured plasma concentrations of exemestane, estrone, estrone sulfate, and estradiol after 14 days of exemestane monotherapy and after approximately 4 weeks of combination therapy. The incidence and severity of adverse events were assessed by physical examination and patient reporting. RESULTS: We treated 18 patients. All had received prior chemotherapy and/or hormonal therapy, eight and six, respectively, with single-agent selective estrogen receptor modulators or irreversible aromatase inhibitors; no hormonal therapy was given within 30 days of study entry. Plasma exemestane concentrations and estrone, estrone sulfate, and estradiol suppression were unchanged after approximately 4 weeks of tamoxifen coadministration. All drug-related adverse events were grades 1 or 2; none was unexpected. Although not a formal study end point, antitumor activity was noted, with two partial responses and four cases of stable disease among 17 evaluable patients after a 9-month median follow-up (range, 2.5-19 months). CONCLUSIONS: This pilot study provides evidence that coadministration of tamoxifen does not affect exemestane pharmacokinetics or pharmacodynamics and that the combination is well-tolerated and active. Further clinical investigation is warranted. 相似文献
978.
Estrogen receptor status in BRCA1- and BRCA2-related breast cancer: the influence of age, grade, and histological type. 总被引:6,自引:0,他引:6
William D Foulkes Kelly Metcalfe Ping Sun Wedad M Hanna Henry T Lynch Parviz Ghadirian Nadine Tung Olufunmilayo I Olopade Barbara L Weber Jane McLennan Ivo A Olivotto Louis R Bégin Steven A Narod 《Clinical cancer research》2004,10(6):2029-2034
PURPOSE: BRCA1-related breast cancers are more frequently estrogen receptor (ER) negative than are either BRCA2-related or nonhereditary breast cancers. The relationship between ER status and other clinical features of hereditary breast cancers has not been well studied. EXPERIMENTAL DESIGN: ER status, grade, and histological tumor type were evaluated in 1131 women with invasive breast cancer, ascertained at 10 centers in North America. There were 208 BRCA1 mutation carriers, 88 BRCA2 carriers, and 804 women without a known mutation. We stratified the patients by mutation status, grade, age, and histological type and calculated the percentage of ER-positive tumors within each stratum. RESULTS: BRCA1 mutation carriers were more likely to have ER-negative breast cancers than were women in other groups, after adjustment for age, grade, and histological subtype (P < 0.001). Only 3.9% of BRCA1-related breast cancers were ER-positive cancers occurring in women in their postmenopausal years. The direction and magnitude of the change in ER status with increasing age at diagnosis in BRCA1 carriers was significantly different from in BRCA2 carriers (P(intercept) = 0.0002, P(slope) = 0.04). Notably, changes in ER status with age at diagnosis for BRCA1 carriers and noncarriers were almost identical (P(slope) = 0.98). CONCLUSIONS: The strong relationship between the presence of a BRCA1 mutation and the ER-negative status of the breast cancers is neither a consequence of the young age at onset nor the high grade but is an intrinsic property of BRCA1-related cancers. The ER-negative status of these cancers may reflect the cell of origin of BRCA1-related cancers. 相似文献
979.
Phase II study of denileukin diftitox for relapsed/refractory B-Cell non-Hodgkin's lymphoma. 总被引:1,自引:0,他引:1
Nam H Dang Fredrick B Hagemeister Barbara Pro Peter McLaughlin Jorge E Romaguera Dan Jones Barry Samuels Felipe Samaniego Anas Younes Michael Wang Andre Goy Maria A Rodriguez Pamela L Walker Yolanda Arredondo Ann T Tong Luis Fayad 《Journal of clinical oncology》2004,22(20):4095-4102
PURPOSE: Denileukin diftitox is a fusion protein combining diphtheria toxin and interleukin-2 (IL-2) that targets tumor cells expressing the IL-2 receptor. Its efficacy has been shown in CD25+ cutaneous T-cell lymphoma, but not in B-cell non-Hodgkin's lymphoma (NHL). A phase II study was performed to evaluate the efficacy and tolerability of denileukin diftitox for relapsed or refractory B-cell NHL. PATIENTS AND METHODS: Patients with relapsed or refractory B-cell NHL were eligible. Tumor CD25 expression was determined by immunohistochemistry or flow cytometry. Denileukin diftitox was administered intravenously at a dose of 18 microg/kg once daily for 5 days every 3 weeks, up to eight cycles. RESULTS: Of the 45 patients assessable for response, 32 (71%) were refractory to the last chemotherapy treatment, and all were previously treated with rituximab. Three complete responses (6.7%) and eight partial responses (17.8%) were observed, for an overall response rate of 24.5%. Nine patients (20%) had stable disease. Objective response rates were similar in CD25+ (22%) and CD25- histologies (29%), as were stable disease rates (22% and 18%, respectively). For responding patients, the median time to treatment failure was 7 months, with a median follow-up in survivors of 18 months (range, 9 to 28 months), and the projected progression-free survival at 20 months was 24% (95% CI, 0% to 60%). Most toxicities were low-grade and transient. CONCLUSION: Denileukin diftitox seems to be effective in relapsed or refractory, CD25+ and CD25- B-cell NHL and is well-tolerated at the dosage evaluated. Evaluation of denileukin diftitox in combination with other agents may be warranted. 相似文献
980.
Paul C Rogers Thomas A Olson John W Cullen Deborah F Billmire Neyssa Marina Frederick Rescorla Mary M Davis Wendy B London Stephen J Lauer Roger H Giller Barbara Cushing 《Journal of clinical oncology》2004,22(17):3563-3569
PURPOSE: To determine whether children with localized gonadal malignant germ cell tumors (MGCT) stage II testicular and stages I and II ovarian treated with four cycles of standard-dose cisplatin combined with etoposide and low-dose bleomycin (PEB) have an event-free survival (EFS) of at least 85% without significant toxicity. PATIENTS AND METHODS: Between May 1990 and July 1995, eligible pediatric patients with stage II or recurrent from stage I (as a stage II) testicular MGCT and stages I and II ovarian MGCT were enrolled onto this Pediatric Oncology Group and Children's Cancer Group study. PEB chemotherapy consisted of bleomycin 15 U/m2 on day 1, cisplatin 20 mg/m2/d on days 1 to 5, and etoposide 100 mg/m2/d on days 1 to 5. Patients received four cycles of therapy at 21-day intervals. RESULTS: Seventy-four patients with a median age of 10.5 years (range, 8.7 months to 16.7 years) were enrolled. Primary sites included: stage II testicular (n = 17), stage I ovarian (n = 41), and stage II ovarian MGCT (n = 16). Treatment with standard PEB resulted in 6-year EFS of 95% and overall survival (OS) of 95.7%. EFS and OS by primary site were as follows: stage II testicular, 100% and 100%; stage I ovarian, 95.1% and 95.1%; and stage II ovarian, 87.5% and 93.8%, respectively. Two patients died from recurrent disease, and one patient died of secondary acute myelocytic leukemia. Infrequent grade 3 to 4 hematologic toxicity was reported. No grade 3 to 4 renal, pulmonary, or ototoxicity was observed. CONCLUSION: Combination chemotherapy with PEB results in excellent EFS and OS with minimal toxicity in children and adolescents with localized gonadal MGCT. 相似文献