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B Duncan

Publications and source records attributed to B Duncan.

At least 37 records · Page 2Linked to original sources
PubMed1999

Office laboratory procedures, office economics, parenting and parent education, and urinary tract infection.

These authors review four areas of office pediatric practice: office laboratory procedures, office economics, parenting and parent education, and urinary tract infections. Thomas Ball reviews the literature published this past year on physician office laboratories, with updates on the Clinical Laboratories Improvement Amendments, laboratory utilization, and office diagnosis of infectious mononucleosis. Eve Shapiro offers an update on office economics, discussing physician organizations and managed care, and a medical ethics evaluation of medical economics. Burris Duncan provides an update on parenting and parent education, with emphasis on defining "the best interests of the child." Richard Wahl summarizes the past year's publications on pediatric urinary tract infections, reviewing the circumcision debate, dysfunctional voiding, vesicoureteral reflux, and the diagnosis and follow-up of acute pyelonephritis.

Child↗
PubMed1999

A social science perspective on screening for Chlamydia trachomatis.

A recent report from the chief medical officer's expert advisory group on Chlamydia trachomatis has recommended the setting up of two pilot projects to assess the feasibility of introducing a national chlamydia screening programme. In addition to screening all symptomatic individuals and all attenders at genitourinary medicine clinics, the report recommends opportunistic screening of sexually active young women and women at high risk of infection, who are attending either general practice or family planning clinics. The success of any new screening programme depends on a wide variety of factors, not least the acceptability of such screening to its target population. In recent years, social scientists have made significant contributions to the understanding of the psychological factors which facilitate or inhibit uptake of screening services. The aim of this report is to discuss briefly the contribution social scientists could make to the chlamydia screening programme in the United Kingdom. In particular, the possible effects of screening for a stigmatized condition such as a sexually transmitted infection are explored.

Ambulatory Care Facilities↗
PubMed1999

Dietary considerations in osteopenia in tube-fed nonambulatory children with cerebral palsy.

Children with nonambulatory cerebral palsy are frequently found to be osteopenic. We sought factors, in addition to immobility and anticonvulsant therapy, that may contribute to the osteopenia. A retrospective chart review of 19 children with nonambulatory cerebral palsy who received gastrostomy tube feedings of standard commercial formulas was performed. Less than 75% of the Recommended Daily Allowance (RDA) was administered to 95% of the children for calories, 58% for calcium, 68% for phosphorus, and 74% for vitamin D. Five of the 19 children sustained fractures without major trauma. This study suggests that inadequate intake of crucial vitamins and minerals may contribute to the severe osteopenia observed in many children with nonambulatory cerebral palsy. The nutritional needs of these children, including those for micronutrients, must be defined and appropriate supplementation given.

Adolescent↗
PubMed1999

Lamivudine/zidovudine as a combined formulation tablet: bioequivalence compared with lamivudine and zidovudine administered concurrently and the effect of food on absorption.

A single-center, open-label, three-way crossover study was conducted in 24 healthy subjects to assess (1) the bioequivalence of a combined lamivudine 150 mg/zidovudine 300 mg tablet relative to the separate brand-name components administered concurrently and (2) the effect of food on the bioavailability of the drugs from the combination tablet. The subjects were randomly assigned to receive each of the following three treatments, separated by a 5- to 7-day washout period: one lamivudine/zidovudine combination tablet after an overnight fast, one lamivudine 150 mg tablet and one zidovudine 300 mg tablet simultaneously after an overnight fast, or one lamivudine/zidovudine combination tablet 5 minutes after completing a standardized high-fat breakfast (67 g fat, 58 g carbohydrate, and 33 g protein). Serial blood samples were collected up to 24 hours postdose for the determination of lamivudine and zidovudine plasma concentrations. Standard pharmacokinetic parameters were estimated. Treatments were considered bioequivalent if 90% confidence intervals for the ratio of least squares (LS) means for the lamivudine and zidovudine area under the plasma concentration-time curve (AUC infinity) and maximum observed plasma concentration (Cmax) fell entirely within 0.80 to 1.25 for log-transformed parameters. The combined lamivudine/zidovudine tablet was bioequivalent in the extent (AUC infinity) and rate of absorption (Cmax and time of Cmax [tmax]) to the individual brand-name drug components administered concurrently under fasted conditions. Geometric LS mean ratios and 90% confidence intervals for AUC infinity and Cmax were 0.97 (0.92, 1.03) and 0.94 (0.84, 1.06), respectively, for lamivudine and 0.99 (0.91, 1.07) and 0.97 (0.82, 1.15), respectively, for zidovudine. The extent of absorption of lamivudine and zidovudine from the combination tablet was not altered by administration with meals, indicating that this formulation may be administered with or without food. However, food slowed the rate of absorption, delayed the tmax, and reduced the Cmax of lamivudine and zidovudine. These changes were not considered clinically important. All formulations were well tolerated under fasted and fed conditions.

Absorption↗
PubMed1999

Pharmacokinetics of lamotrigine in children in the absence of other antiepileptic drugs.

We evaluated the pharmacokinetics of lamotrigine in 12 children with epilepsy who were receiving no other antiepileptic drugs. Each patient received a single oral dose of lamotrigine 2 mg/kg. Plasma concentrations of the drug were measured up to 48 hours after dosing. Pharmacokinetic parameters were calculated using noncompartmental methods. After rapid absorption, the lamotrigine concentration declined monoexponentially. Oral clearance was 0.64 +/- 0.26 ml/min/kg. The apparent volume of distribution was 1.50 +/- 0.51 L/kg. Weight-normalized clearance and volume were higher in children than in adults. The mean half-life was 32 hours, similar to that in adults. Should similar plasma lamotrigine concentrations in adults and children be desirable, children will likely require higher weight-normalized doses at the same dosing frequency.

Anticonvulsants↗
PubMed1999

Lack of effect of cimetidine on the pharmacokinetics of sustained-release bupropion.

The objective of this study was to assess whether cimetidine affects the pharmacokinetics of sustained-release (SR) bupropion hydrochloride and the active metabolite, hydroxybupropion. This randomized, open-label, two-period crossover study was conducted in 24 healthy volunteers 18 to 45 years of age. ANOVA showed that administration of two 150 mg bupropion SR tablets with one 800 mg cimetidine tablet following an overnight fast did not change values for AUC infinity, Cmax, tmax, t1/2, and CL/F (CL/F calculated for bupropion only) for either bupropion or hydroxybupropion as compared with two 150 mg bupropion SR tablets alone. In this study, it appears that there is no effect of cimetidine on the pharmacokinetics of bupropion SR.

Adolescent↗
PubMed1998

Differential expression of cyclin D1 in mantle cell lymphoma and other non-Hodgkin's lymphomas.

Mantle-cell lymphomas are associated with a characteristic chromosomal translocation, t(11;14)(q13;q32). This translocation involves rearrangement of the bcl-1 proto-oncogene from chromosome 11 to the immunoglobulin heavy chain gene on chromosome 14, resulting in an overexpression of cyclin D1 mRNA (also known as bcl-1 and PRAD1). In the current study performed on paraffin-embedded tissue, cyclin D1 mRNA could be detected in 23 of 24 mantle-cell lymphomas by reverse transcription polymerase chain reaction (RT-PCR) whereas only 9 of 24 demonstrated a t(11;14) by PCR. However, we also found that cyclin D1 mRNA could be detected in the majority (11 of 17, 65%) of non-mantle-cell lymphomas and in a minority of atypical lymphoid hyperplasias (3 of 7, 43%). Cyclin D1 mRNA expression was not observed in floridly reactive lymph nodes (0 of 9) or in unstimulated lymph nodes (0 of 20), suggesting that it is a sensitive adjunct marker for malignant lymphoproliferative processes, but not specific for mantle-cell lymphoma. A semiquantitative RT-PCR assay was developed that compared the ratio of cyclin D1 to the constitutively expressed gene beta2-microglobulin. Using this assay on a limited number of our specimens, cyclin D1 overexpression in mantle-cell lymphoma could be reliably distinguished from its expression in other non-Hodgkin's lymphomas. This assay for cyclin D1 expression, designed for formalin-fixed, paraffin-embedded tissue, was a very sensitive and specific marker for mantle-cell lymphoma.

Adult↗
PubMed1998

Implementation and evaluation of a measles/rubella vaccination campaign in a campus university in the UK following an outbreak of rubella.

An age shift in rubella infection to young adults has occurred in Scotland since the introduction of a first dose measles, mumps and rubella (MMR) vaccination in 1988 and a second dose measles/rubella (MR) vaccination in 1994/95. The Health Board was alerted to an outbreak of rubella at Stirling University by the notification of 6 cases amongst male students aged 18-28 years with dates of onset between 3 March and 21 March 1996. In response, a MR vaccination campaign was conducted to enhance population immunity to rubella within the university population and to reduce the likelihood of further cases. A total of 1795 students, staff and visitors were vaccinated. Vaccine coverage of 46% was estimated to be sufficient to boost rubella immunity in full time male students in university accommodation to 88.7-91.0%, just above the upper critical level of herd immunity for rubella of 85-88%. Students in colleges and universities in the UK will remain at increased risk of outbreaks of rubella and measles until the cohort who have received a two dose schedule of MR form the bulk of the college population. It may be prudent for tertiary education colleges and other institutions in the UK with young adults living in shared residential accommodation to offer MR vaccination to new entrants, targeting those who have not previously received the vaccine, between now and the year 2000.

Adolescent↗
PubMed1998

A comparison of the efficacy, safety, and patient satisfaction of ondansetron versus droperidol as antiemetics for elective outpatient surgical procedures. S3A-409 and S3A-410 Study Groups.

UNLABELLED: Two identical, randomized, double-blind, placebo-controlled studies enrolled 2061 adult surgical outpatients at high risk of postoperative nausea and vomiting (PONV) to compare i.v. ondansetron 4 mg with droperidol 0.625 mg and droperidol 1.25 mg for the prevention of PONV. The antiemetic drugs or placebo were administered i.v. 20 min before the induction of anesthesia with a barbiturate compound, followed by maintenance with N2O/isoflurane/enflurane. Nausea, emetic episodes, adverse events, and patient satisfaction were analyzed for the 0 to 2 h and 0 to 24 h postoperative periods. In the 0 to 2 h postoperative period, there was a complete response (no emesis or rescue antiemetic) in 46% of subjects given placebo (P < 0.05 versus antiemetic groups), in 62% given ondansetron, in 63% given droperidol 0.625 mg, and in 69% given droperidol 1.25 mg (P < 0.05 versus ondansetron). In the 0 to 24-h postoperative period, there were no significant differences in complete response between the ondansetron and droperidol 0.625 or 1.25 mg groups; all groups remained superior to placebo. The proportion of patients without nausea during the 0 to 24 h postoperative period was greater in the antiemetic groups compared with the placebo group; however, droperidol 1.25 mg was more effective than ondansetron 4 mg or droperidol 0.625 mg (43% vs 29% or 29%, respectively). Headache incidence was higher in the ondansetron group compared with either droperidol group. Patient satisfaction scores did not differ significantly among antiemetic treatment groups, although all were superior to placebo. In conclusion, all antiemetic treatment regimens were superior to placebo for the prevention of PONV in the immediate postoperative period; however, droperidol 1.25 mg was more efficacious than ondansetron during the early recovery period (0-2 h). There were no significant differences between ondansetron and either droperidol dose for emesis prevention during the 0 to 24 h postoperative period. IMPLICATIONS: More than 2000 patients at high risk of postoperative nausea and vomiting were given either placebo, ondansetron 4 mg, or droperidol 0.625 mg or 1.25 mg i.v. before the administration of general anesthesia. After surgery, the incidence of nausea, vomiting, medication side effects, and patient satisfaction were evaluated for 24 h. Droperidol 0.625 or 1.25 mg i.v. compared favorably with ondansetron 4 mg i.v. for the prevention of postoperative nausea and vomiting after ambulatory surgery.

Adolescent↗
PubMed1998

Office laboratory procedures, office economics, patient and parent education, and urinary tract infection.

This review provides an update on four areas of office practice: office laboratory procedures, office economics, patient and parent education, and urinary tract infection. Thomas Ball reviews physician office laboratories, with updates on the Clinical Laboratory Improvement Amendments, office proficiency testing, and office testing for streptococcal pharyngitis and Helicobacter pylori. Eve Shapiro reports on office economics, focusing on the influence of managed care on pediatric practice. Burris Duncan provides a review of the new National Institutes of Health asthma guidelines, and challenges us to become more involved in patient education. Richard Wahl reviews urinary tract infections, vesicoureteral reflux, dysfunctional voiding, and appropriate imaging studies. Our approach is to provide pediatricians with useful and practical information for their office practices.

Asthma↗
PubMed1997

Office laboratory procedures, office economics, patient and parent education, and urinary tract infection.

This review provides an update on four important areas in office pediatrics: office laboratory procedures, office economics, patient and parent education, and urinary tract infection. Ball reviews new information about physician office laboratories, with updates on the Clinical Laboratory Improvement Amendments, streptococcal pharyngitis, urinalyses, office stool examination, and information on Helicobacter pylori serology. Shapiro reports on office economics, highlighting new office technologies, physician operated networks, managed care, recent legislation, and the "cost versus quality" debate. Duncan provides a very thought provoking essay on parent and patient education, focusing on improving parenting skills. Wahl reviews the recent literature on urinary tract infections, with emphasis on host-bacteria interactions, diagnostic evaluations, pyelonephritis, renal cortical scarring, and long term follow-up of vesicoureteral reflux. We hope we have provided pediatricians with useful and practical information for their office practices.

Child↗
PubMed1996

Molecular docking programs successfully predict the binding of a beta-lactamase inhibitory protein to TEM-1 beta-lactamase.

Crystallization of the 1:1 molecular complex between the beta-lactamase TEM-1 and the beta-lactamase inhibitory protein BLIP has provided an opportunity to put a stringent test on current protein-docking algorithms. Prior to the successful determination of the structure of the complex, nine laboratory groups were given the refined atomic coordinates of each of the native molecules. Other than the fact that BLIP is an effective inhibitor of a number of beta-lactamase enzymes (KI for TEM-1 approximately 100 pM) no other biochemical or structural data were available to assist the practitioners in their molecular docking. In addition, it was not known whether the molecules underwent conformational changes upon association or whether the inhibition was competitive or non-competitive. All six of the groups that accepted the challenge correctly predicted the general mode of association of BLIP and TEM-1.

Amino Acid Sequence↗
PubMed1996

Hepatitis in used syringes: the limits of sensitivity of techniques to detect hepatitis B virus (HBV) DNA, hepatitis C virus (HCV) RNA, and antibodies to HBV core and HCV antigens.

Hepatitis virus infections are common among injecting drug users. Syringes containing hepatitis B virus (HBV) DNA and hepatitis C virus (HCV) RNA were identified by polymerase chain reaction (PCR); syringes containing antibodies to HBV core antigen and HCV were identified by EIA. Syringe use was simulated to determine the sensitivity of these assays. The mean limits for PCR were 0.082 microliter of blood for HBV and 0.185 microliter for HCV; the mean limits for EIA were 0.185 microliter for HBV and 0.023 microliter for HCV. HBV PCR testing of 681 syringes returned to the needle exchange program in New Haven, Connecticut, revealed a decline from 7.8% HBV-positive at the program's outset to 2.6%. HCV antibodies were found in 12.1% of 207 syringes tested. Syringe testing can help estimate the prevalence and incidence of hepatitis virus infections when standard seroepidemiologic analyses cannot be applied.

Base Sequence↗
PubMed1996

Office laboratory procedures, office economics, patient and parent education, and urinary tract infection.

This review updates our readers on four important areas of office practice: office laboratory procedures, office economics, patient and parent education, and urinary tract infection. Michael Aldous reviews the recent literature on office laboratory procedures, which includes a report on the ongoing heated discussion of the Clinical Laboratory Improvement Amendments, an update of recent studies on new and better rapid streptococcal tests, and improved methods for urinalysis. Rickey Williams provides a report on office economics that includes a discussion of the effects of capitation, how preventive care can be cost effective, and the future prospects for greatly expanded office computerization. Burris Duncan discusses patient and parent education with an in-depth review of the potential economic value of a full implementation of the American Academy of Pediatrics' The Injury Prevention Program, and in addition he chronicles the rapid growth and development of school-based health centers. John Ey reviews the recent literature on urinary tract infections in children, including how we can make the diagnosis, methods for preventing recurrent urinary tract infections, the most effective studies for evaluating the urinary system, and what follow-up is necessary. We hope this review will provide the pediatrician with important information to help in the care of their patients.

Adolescent↗
PubMed1995

Office laboratory procedures, office economics, patient and parent education, and urinary tract infection.

This section updates the reader on four important areas of office practice: office laboratory procedures, office economics, patient and parent education, and urinary tract infections. Dr. Michael Aldous reviews the recent literature about office laboratory procedures, including the continued impact of the Clinical Laboratory Improvement Ammendments, what is new in the diagnosis of streptococcal pharyngitis, urinalysis improvements, the diagnosis of anemia, and which patients should undergo cholesterol screening. Dr. Rickey Williams discusses the literature on office economics, including new technology for billing and charting, whether pediatricians should bill for telephone calls, and the latest information on health care policy and the changes offices are facing with the growing managed care market. Dr. Burris Duncan reviews patient and parent education, including new apporaches to infant colic, sleep positioning for the prevention of sudden infant death, the need for the hepatitis B vaccine (which has been slowly implemented), and finally ways that pediatricians can help with parenting. Dr. John Ey discusses the recent literature on urinary tract infections in children, including better ways of making the diagnosis, whether there are any new treatment approaches for urinary tract infections, useful investigational studies for evaluating the urinary system, and how best to follow up children with infected urinary tracts. We hope that this review will help the practicing pediatrician to better care for patients and provide each of you with a greater satisfaction in delivering health care in an office setting.

Child↗