Search PubMed⌕ Search

Biomedical subjects

A Pearson

Publications and source records attributed to A Pearson.

At least 55 records · Page 3Linked to original sources
PubMed2000

EUS to detect evidence of pancreatic disease in patients with persistent or nonspecific dyspepsia.

BACKGROUND: Mild chronic pancreatitis is difficult to diagnose and the diagnosis is therefore not sought routinely in patients with dyspepsia. The aim of our study was to compare the prevalence of endosonographic pancreatic abnormalities in patients with dyspepsia and control subjects. METHODS: The number of endosonographic abnormalities was compared prospectively in patients with dyspepsia and control patients. Patients in whom there was any suspicion of pancreatic disease were analyzed separately. RESULTS: Between November 1998 and January 1999, 156 patients with dyspepsia were compared with 27 control patients. The groups were similar except that control patients were significantly older and more likely to be men. The mean number of endosonographic abnormalities was higher in dyspeptic patients than in control patients (mean number of abnormalities 3.3: 95% CI [2.9, 3.6] vs. 1.9: 95% CI [0.3, 1.7]). The strongest independent predictors of severe endosonographic abnormalities (defined as 5 or more abnormalities) were the presence of suspected pancreatic disease (odds ratio 7.29: 95% CI [2.03, 26. 14]) and dyspepsia (odds ratio 7.21: 95% CI [1.99, 26.26]). In the dyspepsia group, no clinical variables were significant predictors of severe abnormalities. However, most patients had nonspecific-type dyspepsia or persistent symptoms after therapeutic trials of acid suppression. CONCLUSIONS: Dyspepsia may be an atypical presentation of pancreatic disease in patients with persistent or nonspecific symptoms. Endosonography may be useful to screen for pancreatic disease in patients with persistent dyspepsia.

Adult↗
PubMed1999

Activation of the murine dihydrofolate reductase promoter by E2F1. A requirement for CBP recruitment.

The E2F family of heterodimeric transcription factors plays an important role in the regulation of gene expression at the G1/S phase transition of the mammalian cell cycle. Previously, we have demonstrated that cell cycle regulation of murine dihydrofolate reductase (dhfr) expression requires E2F-mediated activation of the dhfr promoter in S phase. To investigate the mechanism by which E2F activates an authentic E2F-regulated promoter, we precisely replaced the E2F binding site in the dhfr promoter with a Gal4 binding site. Using Gal4-E2F1 derivatives, we found that E2F1 amino acids 409-437 contain a potent core transactivation domain. Functional analysis of the E2F1 core domain demonstrated that replacement of phenylalanine residues 413, 425, and 429 with alanine reduces both transcriptional activation of the dhfr promoter and protein-protein interactions with CBP, transcription factor (TF) IIH, and TATA-binding protein (TBP). However, additional amino acid substitutions for phenylalanine 429 demonstrated a strong correlation between activation of the dhfr promoter and binding of CBP, but not TFIIH or TBP. Finally, transactivator bypass experiments indicated that direct recruitment of CBP is sufficient for activation of the dhfr promoter. Therefore, we suggest that recruitment of CBP is one mechanism by which E2F activates the dhfr promoter.

3T3 Cells↗
PubMed1999

Effects of size of health service on scope of rural nursing practice.

This paper presents the findings of an analysis of the activities of rural nurses from a national audit of the role and function of the rural nurse (Hegney, Pearson and McCarthy 1997). The results suggest that the size of the health service (defined by the number of acute beds) influences the activities of rural nurses. Further, the study reports on the differences of the context of practice between different size rural health services and the impact this has on the scope of rural nursing practice. The paper will conclude that the size of the health service is an outcome of rurality (small population densities, distance from larger health facilities, lack of on-site medical and allied health staff). It also notes that the size of the health service is a major contextual determinant of patient acuity and staff skill-mix in small rural hospitals, and therefore the scope of rural nursing practice.

Attitude of Health Personnel↗
PubMed1999

The ocular and systemic prognosis of patients presenting with sarcoid uveitis.

PURPOSE: To describe the visual and systemic outcomes in patients presenting with sarcoid uveitis. METHODS: Seventy-five patients with definite or presumed sarcoid uveitis were followed up for a median of 4 years. The patients came from a primary ophthalmic referral centre and a specialist uveitis centre. The prognostic value of demographic and clinical features at the onset of disease were studied. Baseline and outcome variables were analysed by survival analysis. RESULTS: After 10 years, 54% of patients retained normal visual acuity and 4.6% had lost vision to less than 6/36 in both eyes. Fifty-one per cent required oral steroids for uveitis and a further 11% needed additional immunosuppressants. Twenty-one per cent of patients had undergone a surgical procedure. At the onset of uveitis the lung was the most common organ involved (35%). After 10 years follow-up disease spread to other organs in 13 patients (17%); in 8 of 13 patients this was the central nervous system. The only outcome associated with baseline variables was bilateral visual loss, which was more likely in those over 40 years at presentation (p = 0.004). CONCLUSIONS: The ocular prognosis of sarcoid uveitis is unrelated to the extent of disease at onset. Patients with extraocular disease fared no differently from those with isolated ocular disease. Patients with sarcoid uveitis are at risk of neurological involvement for at least 15 years.

Adolescent↗
PubMed1999

Effects of noradrenaline, the calcium ionophore A23187, forskolin, sodium nitroprusside and glibenclamide on the degradation of extracellular adenosine 5'-triphosphate by the rat isolated vas deferens.

1. The effects of noradrenaline (NA), the calcium ionophore A23187, forskolin, sodium nitroprusside (SNP) and the K+-channel blocker glibenclamide on the degradation by ectonucleotidases of extracellular adenosine 5'-triphosphate (ATP) were studied in the rat vas deferens. 2. ATP (100 microM) was rapidly broken down by the rat vas deferens with a half-life of 5.83 +/- 0.40 min via adenosine 5'-diphosphate (ADP) and adenosine 5'-monophosphate (AMP), with the final degradation product being inosine and with little adenosine being detected in the samples. 3. Preincubation for 1 h with NA (10 microM), A23187 (10 microM), or glibenclamide (100 microM) had no significant effect on the breakdown of ATP or the production of metabolites. However, both forskolin (10 microM) and SNP (1 microM) significantly increased the concentrations of AMP detected with time. In the case of SNP (1 microM) there was also a significant reduction in the rate of production of inosine, while in the case of forskolin (10 microM) there was a significant increase in the rate of removal of ATP. 4. These results suggest that preincubation with SNP may inhibit 5'-nucleotidase and so reduce the metabolism of AMP, while preincubation with forskolin may increase the activity of the ectonucleotidases responsible for production of AMP from ATP.

5'-Nucleotidase↗
PubMed1998

Effect of treatment of isolated systolic hypertension on left ventricular mass.

CONTEXT: Left ventricular (LV) hypertrophy is a common problem among elderly patients with isolated systolic hypertension (ISH), but the effect of treatment of ISH on LV mass is not known. OBJECTIVE: To assess the ability of antihypertensive drug treatment to reduce LV mass in ISH. DESIGN: Echocardiographic Substudy of the Systolic Hypertension in the Elderly Program (SHEP). PATIENTS: A total of 104 participants at the St Louis SHEP site who had interpretable baseline echocardiograms, 94 of whom had 3-year follow-up echocardiograms. INTERVENTION: The SHEP participants were randomized to placebo or active treatment with chlorthalidone (12.5-25 mg/d), with atenolol (25-50 mg/d) added if necessary to maintain goal blood pressure. MAIN OUTCOME MEASURE: Change in LV mass assessed by echocardiography. RESULTS: Minimum follow-up was 3 years. In the active treatment group, 91% and 80% of subjects were receiving treatment with chlorthalidone alone by the end of years 1 and 3, respectively. The LV mass index was 93 g/m2 in the active treatment group and 100 g/m2 in the placebo group (P<.001). The LV mass index declined by 13% (95% confidence interval, - 3% to - 23%) in the active treatment group compared with a 6% increase (95% confidence interval, - 3% to + 16%) in the placebo group over 3 years (P=.01). CONCLUSION: Treatment of ISH with a diuretic-based regimen reduces LV mass.

Aged↗
PubMed1998

The development of bases for trait attribution: children's understanding of traits as causal mechanisms based on desire.

Two studies investigated 4- to 7-year-old children's understanding that traits can be causal mechanisms based on desires, as well as mere summaries of behavioral regularities. In Experiment 1, children made predictions given trait information. Children from 5 years made different emotion predictions about the same situation for actors with different traits, thus appreciating traits as psychological causes. For behavior prediction, children over age 4 generalized across situations. In Experiment 2, accurate emotion prediction by 3- to 7-year-olds was linked to understanding desire as a subjective mental property. The results suggest that children change from viewing traits as behavioral regularities to understanding them as internal mediators, and that advances in understanding desire underlie this change. These changes in understanding traits extend research on theory of mind beyond the basic concepts of desire and belief.

Adult↗
PubMed1998

Multivariate analysis of risk factors in stage 4 neuroblastoma patients over the age of one year treated with megatherapy and stem-cell transplantation: a report from the European Bone Marrow Transplantation Solid Tumor Registry.

PURPOSE: The European Bone Marrow Transplantation (EBMT) Solid Tumor Registry (STR) contains detailed information on children with advanced neuroblastoma who, after standard-dose induction chemotherapy and surgery, received myeloablative megatherapy (MGT) followed by stem-cell transplantation (SCT). This data base was analyzed to identify factors that predict event-free survival (EFS). PATIENTS AND METHODS: Eligibility criteria were stage IV neuroblastoma, age over 1 year at diagnosis, and no relapse before MGT/SCT. Between February 1978 and July 1992, 549 patients were registered by 36 European transplant centers. The median age at diagnosis was 36 months (range, 13 to 216 months) and the male-female ratio was 1:45. Before MGT, 157 patients were in complete remission (CR), 156 in very good partial remission (VGPR), and 208 in partial remission (PR), whereas 24 had had only a minor response (MR). One hundred ten of 546 patients had undergone two successive MGT procedures. The median observation time was 60 months (range, 12 to 187 months). RESULTS: Actuarial EFS is 26% at 5 years. Multivariate analysis by the Cox proportional hazards regression model included 529 patients with complete data sets. After adjustment for treatment duration before MGT and double MGT procedures, two adverse, independent risk factors that influenced EFS were identified: (1) persisting skeletal lesions before MGT as defined by technetium (99TC) scans and/or meta-iodobenzylguanidine (mIBG) scans (P = .004) and (2) persisting bone marrow involvement before MGT (P = .03). CONCLUSION: After induction treatment, persisting skeletal disease as defined above and persisting bone marrow involvement may be predictive of a particularly poor outcome. Physicians may consider this an additional important tool to decide the patient's management.

Adolescent↗
PubMed1998

Conduct of phase I trials in children with cancer.

PURPOSE AND METHODS: Future progress in the care of children with cancer requires appropriate evaluations of promising new agents for pediatric indications, beginning with well-conducted phase I trials. This report summarizes current guidelines for the conduct of pediatric phase I trials and represents a consensus between American and European investigators. The primary objective of pediatric phase I trials is to define safe and appropriate doses and schedules of new agents that can subsequently be used in phase II trials to test for activity against specific childhood malignancies. Prioritization of agents for evaluation in children is critical, since many more investigational agents are evaluated in adult patients than can be systematically evaluated in children. Considerations used in prioritizing agents include activity in xenograft models, novel mechanism of action, favorable drug-resistance profile, and activity observed in adult trials of the agent. RESULTS AND CONCLUSION: Distinctive characteristics of pediatric phase I trials, in comparison to adult phase I trials, include the necessity for multiinstitutional participation and their higher starting dose (typically 80% of the adult maximum-tolerated dose [MTD]), both of which reflect the relative unavailability of appropriate patients. The application of uniform eligibility criteria and standard definitions for MTD and dose-limiting toxicity (DLT) help to assure that pediatric phase I trials are safely conducted and reliably identify appropriate doses and schedules of agents for phase II evaluation. Where possible, pediatric phase I trials also define the pharmacokinetic behavior of new agents in children.

Antineoplastic Agents↗