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91.
BACKGROUND AND AIM: Statistical signal detection methods such as proportional reporting ratios (PRRs) detect many drug safety signals when applied to databases of spontaneous suspected adverse drug reactions (ADRs). Impact analysis is a tool that was developed as an aid to prioritisation of such signals. This paper describes a pilot project whereby impact analysis was simultaneously introduced into practice in a regulatory setting and tested in comparison with the existing approach. METHODS: Impact analysis was run on signals detected during a 26-week period from the UK Adverse Drug Reactions On-line Information Tracking (ADROIT) database of spontaneous ADRs that met minimum criteria (PRR>or=3.0, chi2>or=4.0 and >or=3 reported cases) and related to established drugs (i.e. those that have been available for at least 2 years and no longer carry the 'black triangle' symbol). The current method of signal prioritisation (i.e. the collective judgement at a weekly meeting) was initially performed without knowledge of the findings of impact analysis. Subsequently, the meeting was presented with the findings and, where appropriate, given the opportunity to reconsider the judgement made. The categories arising from the two methods were compared and the ultimate action recorded. Inter-observer variation between scientists performing impact analysis was also assessed. RESULTS: Eighty-six separate signals were analysed by impact analysis, of which 5% were categorised as high priority (A), 14% as requiring further information (B), 31% as low priority (C) and 50% as no action required (D). In general, the new method tended to give a higher level of priority to signals than the existing approach. Overall, there was 59% agreement between the impact analysis and the collective judgement at the meetings (kappa statistic=0.30). There was slightly greater agreement between impact analysis and the final action taken (kappa statistic=0.39), indicating that the findings of an impact analysis had an influence on the outcome. Assessment of inter-observer variation demonstrated that the method is repeatable (kappa statistic for overall category=0.77). Almost 70% of those who participated in the pilot study believed that impact analysis represented an improvement in how signals were prioritised. CONCLUSIONS: Impact analysis is a repeatable method of signal prioritisation that tended to give a higher level of priority to signals than the standard approach and which had an influence on the ultimate outcome.  相似文献   
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PURPOSE: Liposomal lurtotecan (OSI-211) is a liposomal formulation of the water-soluble topoisomerase I inhibitor lurtotecan (GI147211), which demonstrated superior levels of activity compared with topotecan in preclinical models. We studied two schedules of OSI-211 in a randomized design in relapsed ovarian cancer to identify the more promising of the two schedules for further study. PATIENTS AND METHODS: Eligible patients had measurable epithelial ovarian, fallopian, or primary peritoneal cancer that was recurrent after one or two prior regimens of chemotherapy. Patients were randomly assigned to receive either arm A (OSI-211 1.8 mg/m(2)/d administered by 30-minute intravenous infusion on days 1, 2, and 3 every 3 weeks) or arm B (OSI-211 2.4 mg/m(2)/d administered by 30-minute intravenous infusion on days 1 and 8 every 3 weeks). The primary outcome measure was objective response, which was confirmed by independent radiologic review, and a pick the winner statistical design was used to identify the schedule most likely to be superior. RESULTS: Eighty-one patients were randomized between October 2000 and September 2001. The hematologic toxic effects were greater on arm A than on arm B (grade 4 neutropenia, 51% v 22%, respectively), as was febrile neutropenia (26% v 2.4%, respectively). Of the 80 eligible patients, eight patients (10%) had objective responses; six responders (15.4%; 95% CI, 6% to 30%) were in arm A and two responders (4.9%; 95% CI, 1% to 17%) were in arm B. CONCLUSION: The OSI-211 daily for 3 days intravenous schedule met the statistical criteria to be declared the winner in terms of objective response. This schedule was also associated with more myelosuppression than the schedule of OSI-211 administered in arm B.  相似文献   
93.
PURPOSE: There are significant differences in reported frequencies, modes of inactivation, and clinical significance of CDKN2A in urothelial cell carcinoma (UCC). We aimed to address these issues by investigating all possible modes of inactivation and clinicopathologic variables in a single tumor panel. EXPERIMENTAL DESIGN: Fifty microdissected UCCs were examined. CDKN2A gene dosage (quantitative real-time PCR), allelic status (microsatellite analysis), hypermethylation (methylation-specific PCR), mutation status (denaturing high-performance liquid chromatography and sequencing), protein expression (immunohistochemistry), and clinicopathologic variables (stage, grade, and disease recurrence during follow-up) were assessed. RESULTS: Exon 2 was underrepresented in 20 of 46 (43%) and exon 1beta in 21 of 46 (46%) of cases. Underrepresentation of exon 2 was accompanied by loss of heterozygosity (LOH) of 9p in 6 of 18 (30%) and of exon 1beta in 11 of 19 assessable cases (58%). Overall, LOH of 9p was identified in 15/41 (37%). Homozygous deletion of exons 2 and 1beta was detected in 16 of 46 (35%) and 10 of 46 tumors (22%), respectively. Co-deletion was most common, but exon 2-specific homozygous deletion was also detected. In tumors without homozygous deletion, p16 promoter hypermethylation was detected in 1 of 18 (6%). Hypermethylation of the p14ARF promoter or mutations in CDKN2A were not observed. Homozygous deletion of exon 2 or LOH on 9p were associated with invasion. Homozygous deletion of exon 2 or exon 1beta was associated with recurrent disease. CONCLUSIONS: These results confirm CDKN2A as a clinically relevant target for inactivation in UCC and show that the true frequency of alteration is only revealed by comprehensive analysis. Our results suggest that CDKN2A may be haploinsufficient in human cancer.  相似文献   
94.
Researchers and clinicians worldwide share concerns that many youngsters with attention-deficit/hyperactivity disorder (ADHD) and/or disruptive behaviour disorders (DBDs) do not receive appropriate treatment despite availability of effective therapies. At the request of Johnson and Johnson (sponsor), 11 international experts in child and adolescent psychiatry were selected by Professor Stan Kutcher (chair) to address these concerns. This paper describes the experts' consensus conclusions, including treatment practice suggestions for physicians involved in the early treatment of youngsters with ADHD (or hyperkinetic disorder, in countries preferring this classification) and/or DBDs internationally: suggested first-line treatment for ADHD without comorbidity is psychostimulant medication aided by psychosocial intervention. For ADHD with comorbid conduct disorder (CD), psychosocial intervention combined with pharmacotherapy is suggested. For primary CD, suggested first-line treatment is psychosocial intervention, with pharmacotherapy considered as an 'add-on' when aggression/impulsivity is marked and persistent. Pharmacotherapy requires careful titration; full-day coverage is the suggested goal. Regular long-term follow-up is recommended.  相似文献   
95.
Low-dose exposure of neonatal mice to nicotine has earlier been shown to induce an altered behavioral response to nicotine in adulthood. Organophosphorus insecticides are known to affect the cholinergic system by inhibition of acetylcholinesterase. This study was undertaken to investigate whether neonatal exposure to nicotine makes mice more susceptible to a known cholinergic agent. Neonatal, 10-day-old, male mice were exposed to nicotine-base (33 microg/kg body weight) or saline s.c. twice daily on five consecutive days. At 5 months of age the animals were exposed to paraoxon (0.17 or 0.25 mg/kg body weight [29% and 37% inhibition of cholinesterase, respectively]) or saline sc every second day for 7 days. Before the first paraoxon injection, the animals were observed for spontaneous motor behavior. The spontaneous motor behavior test did not reveal any differences in behavior between the treatment groups. Immediately after the spontaneous behavior test, the animals received the first injection of paraoxon and were observed for acute effects of paraoxon on spontaneous motor behavior. The acute response to paraoxon in the spontaneous motor behavior test was a decreased level of activity in mice neonatally exposed to nicotine. Control animals showed no change in activity. Two months after the paraoxon treatment, the animals were again tested for spontaneous motor behavior. Animals neonatally exposed to nicotine and exposed to paraoxon as adults showed a deranged spontaneous motor behavior, including hyperactivity and lack of habituation.  相似文献   
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98.
Reflex sympathetic dystrophy, also known as complex regional pain syndrome (CRPS), has recently been shown to be associated with autoantibodies against β2‐adrenergic and muscarinic M2 receptors. In addition to pain and sudomotor/vasomotor symptoms, dysautonomia is also observed in a subset of CRPS patients. Despite its severity, there are few effective therapies for CRPS described to date. We report a case of a 14‐year‐old girl with CRPS of her right leg and dysautonomia (gastroparesis, postural tachycardia) refractory to multiple therapies, successfully treated with therapeutic plasma exchange (TPE) with albumin replacement. The patient, who has serum anti β2‐adrenergic and muscarinic M2 receptor autoantibodies in addition to nicotinic acetylcholine receptor ganglionic autoantibodies, underwent an initial course of five TPEs over a 2‐week period. She demonstrated a clinical response to TPE as manifested by a rapid improvement in her fatigue and gastroparesis, with a gradual yet significant improvement in her leg pain and sudomotor/vasomotor flares. Following the loading procedures, the patient was treated with rituximab. She continues to require periodic TPE to maintain a remission, with additional immunosuppression being considered long term. Although further studies are needed, TPE (in combination with immunosuppression) may be an appropriate therapy for CRPS patients with detectable autoantibodies, as it is for better characterized diseases with autoantibodies against neuronal surface receptors such as myasthenia gravis or Lambert Eaton myasthenic syndrome. J. Clin. Apheresis 31:368–374, 2016. © 2015 Wiley Periodicals, Inc.  相似文献   
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The repetitive behaviour questionnaire (RBQ) (Turner, 1995) is one of the three most commonly used interview/questionnaire measures of repetitive behaviour (Honey et al., in preparation). Despite this there is a scarcity of information concerning its structure, reliability and validity. The psychometric properties of the RBQ were examined when used with children with an autism spectrum disorder, children of typical development and children with a learning disability. The questionnaire was found to examine two valid and reliable factors of repetitive behaviour and to have good levels of concurrent and construct validity. This novel study provides researchers and clinicians with information necessary to make decisions about the RBQ's utility and for the evaluation of conclusions drawn from existing research, which has used the RBQ.  相似文献   
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