Lithotripsy for ureteric stones: throw away the ureteroscope.
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Humans↗
Biomedical subjects
J Ramsay
Publications and source records attributed to J Ramsay.
Evaluation of support materials for the surface immobilization and decoloration of amaranth by Trametes versicolor.
The ability of Trametes versicolor ATCC 20869 to colonize several natural and synthetic materials (wheat straw, jute, hemp, maple woodchips, and nylon and polyethylene teraphthalate fibers) and to subsequently decolorize amaranth was evaluated. Jute was found to be the best support material as T. versicolor grew well on it without color leaching from the support and without loss of the jute's integrity over a 4 week period. The fungus immobilized on jute, straw and hemp decolorized amaranth (50 mg l(-1)) at a rate of about 5 mg l(-1) h(-1) without glucose being added. When 1 g l(-1) glucose was added, the dye was degraded more quickly (about 8 mg l(-1) h(-1)). Decoloration did not occur in a suspension culture without glucose. As the number of decoloration cycles increased, the rate of decoloration decreased. This rate was restored to its original level after the biomass was incubated in fresh growth medium for 5 days. With all immobilization supports, the toxicity of the medium before and after decoloration was the same or lower.
Amaranth Dye↗
Age, gender, socioeconomic, and ethnic differences in patients' assessments of primary health care.
BACKGROUND: Patients' evaluations are an important means of measuring aspects of primary care quality such as communication and interpersonal care. This study aims to examine variations in assessments of primary care according to age, gender, socioeconomic, and ethnicity variables. METHODS: A cross sectional survey of consecutive patients attending 55 inner London practices was performed over a 2 week period using the General Practice Assessment Survey (GPAS) instrument which assesses 13 important dimensions of primary care provision. Variations in scale scores were investigated for differences relating to age, gender, socioeconomic, and ethnic status as reported by respondents. RESULTS: A total of 7692 questionnaires were returned (71% response rate). Valid information on age, gender, socioeconomic status, and ethnicity was available for 4819 out of 5496 adult respondents. Approximately half the respondents reported their ethnic group as "white" and most of the remaining respondents reported belonging to "black" or South Asian groups. Significant differences existed between groups of patients defined by age or ethnicity for most of the scale scores examined. Black, South Asian, and Chinese respondents reported lower scores (representing less favourable assessments) than white respondents; older respondents reported more favourable evaluations of care than younger respondents; and less affluent groups reported lower scores than more affluent groups for two of the 13 dimensions. There was no significant difference between gender groups with respect to assessment of primary care. Age and ethnicity were independent predictors of respondents' assessments of primary care. CONCLUSIONS: Differences exist between identifiable subgroups of the population in their assessments of primary health care measured using the GPAS instrument. This work adds to the literature on variation in healthcare experience and the potential for patient assessment of primary care. Further work is required to investigate these differences in more detail and to relate them to differences in the nature and process of primary care provision. Primary care providers need to ensure that services provided are appropriate for all patient groups within their communities.
Adolescent↗
Practice size: impact on consultation length, workload, and patient assessment of care.
BACKGROUND: Variations in practice list size are known to be associated with changes in a number of markers of primary care. Few studies have addressed the issue of how single-handed and smaller practices compare with larger group practices and what might be the optimal size of a general practice. AIM: To examine variations in markers of the nature of the care being provided by practices of various size. DESIGN OF STUDY: Practice profile questionnaire survey. SETTING: A randomised sample of general practitioners (GPs) and practices from two inner-London areas, stratified according to practice size and patients attending the practice over a two-week period. METHOD: Average consultation length was calculated over 200 consecutive consultations. A patient survey using the General Practice Assessment Survey instrument was undertaken in each practice. A practice workload survey was carried out over a two-week period. These outcome measures were examined in relation to five measures of practice size based on total list size and the number of doctors providing care. RESULTS: Out of 202 pratices approached, 54 provided analysable datasets. The patient survey response rate was 7247/11,000 (66%). Smaller practices had shorter average consultation lengths and reduced practice performance scores compared with larger practices. The number of patients corrected for the number of doctors providing care was an important predictor of consultation length in group practices. Responders from smaller practices reported improved accessibility of care and receptionist performance, better continuity of care compared with larger practices, and no disadvantage in relation to 10 other dimensions of care. Practices with smaller numbers of patients per doctor had longer average consultation lengths than those with larger numbers of patients per doctor. CONCLUSION: Defining the optimal size of practice is a complex decision in which the views of doctors, patients, and health service managers may be at variance. Some markers of practice performance are related to the total number of patients cared for, but the practice size corrected for the number of available doctors gives a different perspective on the issue. An oversimplistic approach that fails to account for the views of patients as well as health professionals is likely to be disadvantageous to service planning.
Family Practice↗
Mutation analysis of BRCA1 and BRCA2 cancer predisposition genes in radiation hypersensitive cancer patients.
PURPOSE: The dose intensity of radiotherapy (RT) used in cancer treatment is limited in rare individuals who display severe normal tissue reactions after standard RT treatments. Novel predictive assays are required to identify these individuals prior to treatment. The mechanisms responsible for such reactions are unknown, but may involve dysfunction of genes involved in the sensing and response of cells to DNA damage. The breast cancer susceptibility genes BRCA1 and BRCA2 are implicated in DNA damage repair and the control of genome stability. The purpose of this study was to determine if clinical radiation hypersensitivity is related to mutations of the BRCA1 and BRCA2 genes. Such information is of potential use in the clinical management of BRCA mutation carriers and their families. METHODS AND MATERIALS: Twenty-two cancer patients who developed severe normal tissue reactions after RT were screened for mutations of BRCA1 and BRCA2, using various methods including protein truncation testing, direct DNA sequencing, and a PCR-based BRCA1 exon 13 duplication test. RESULTS: No mutations were detected in the 22 patients tested, despite screening for the majority of commonly described types of mutations of BRCA1 and BRCA2. CONCLUSION: These early results suggest that genes other than BRCA1 and BRCA2 probably account for most cases of clinical radiation hypersensitivity, and that screening for mutations of BRCA1 and BRCA2 is unlikely to be useful in predicting response to radiotherapy. However, it has not been excluded that some BRCA1 or BRCA2 heterozygotes might experience unexpected RT toxicity; further BRCA mutation screening on radiation sensitive individuals is warranted.
BRCA2 Protein↗
Reduction of gait data variability using curve registration.
Timing in peak gait values shifts slightly between gait trials. When averaged, the standard deviation (S.D.) in gait data may increase due to this inter-trial variability unless normalization is carried out beforehand. The objective of this study was to determine how curve registration, an alignment technique, can reduce inter-subject variability in gait data without perturbing the curve characteristics. Twenty young, healthy men participated in this study each providing a single gait trial. Gait was assessed by means of a four-camera high-speed video system synchronized to a force plate. A rigid body three-segment model was used in an inverse dynamic approach to calculate three-dimensional muscle powers at the hip, knee and ankle. Curve registration was applied to each of the 20 gait trials to align the peak powers. The mean registered peak powers increased by an average of 0.10 +/- 0.13 W/kg with the highest increases in the sagittal plane at push-off. After performing curve registration, the RMS values decreased by 13.6% and the greatest reduction occurred at the hip and knee, both in the sagittal plane. No important discontinuities were reported in the first and second derivatives of the unregistered and registered curves. Curve registration did not have much effect on the harmonic content. This would be an appropriate technique for application prior to any statistical analysis using able-bodied gait patterns.
Adult↗
Case 8--2000. Intraoperative bispectral index monitoring and early extubation after cardiac surgery in patients with a history of awareness under anesthesia.
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Aged↗
The General Practice Assessment Survey (GPAS): tests of data quality and measurement properties.
OBJECTIVES: The aim of this study was to describe the psychometric properties of the General Practice Assessment Survey (GPAS) and its acceptability to patients in the UK. GPAS comprises seven multiple item scales and two single item scales addressing nine key areas of primary care activity (access, technical care, communication, inter-personal care, trust, knowledge of patient, nursing care, receptionists and continuity of care). A further four single items relate to patients' perceptions of the GP's role in referral and co-ordination of care, their willingness to recommend their GP and their overall satisfaction with care received. METHODS: Two hundred consecutive patients attending routine consulting sessions at 55 inner London practices were invited to complete the GPAS questionnaire. The acceptability, reliability and validity of GPAS was assessed using standard psychometric techniques. RESULTS: Out of 11 000 patients, 7247 (66%) completed a questionnaire in a GP surgery. Fifty-five out of a separate sample of 77 patients attending one practice completed a second questionnaire mailed to them 1 week following their attendance. GPAS was acceptable to patients as evidenced by low proportions of missing data for all items, and a full range of possible scores for all but one of the nine scales. Reliability of the instrument was good. Multiple item scales had excellent internal consistency, high item-total correlations, and test-retest reliability. Scaling assumptions were confirmed, with six of the seven scales achieving 100% scaling success (convergent and discriminant validity). Construct validity was evident, although this requires further evaluation against external measures. CONCLUSIONS: GPAS is a useful instrument for assessing several important dimensions of primary care. It is acceptable, reliable and valid, and has the potential for versatility in mode of administration. It will be a useful instrument for practices, primary care groups and primary care researchers evaluating key areas of primary care activity. Further work is required to evaluate its performance in non-inner-city settings and to evaluate further its validity against external criteria.
Adolescent↗
Expanding campus safety objectives.
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Environmental Health↗
Preoperative serum potassium levels and perioperative outcomes in cardiac surgery patients. Multicenter Study of Perioperative Ischemia Research Group.
CONTEXT: Although potassium is critical for normal electrophysiology, the association between abnormal preoperative serum potassium level and perioperative adverse events such as arrhythmias has not been examined rigorously. OBJECTIVE: To determine the prevalence of abnormal preoperative serum potassium levels and whether such abnormal levels are associated with adverse perioperative events. DESIGN AND SETTING: Prospective, observational, case-control study of data collected from 24 diverse US medical centers in a 2-year period from September 1, 1991, to September 1, 1993. PATIENTS: A total of 2402 patients (mean [SD] age, 65.1 [10.3] years; 24% female) undergoing elective coronary artery bypass grafting who were not enrolled in another protocol. The study population was identified using systematic sampling of every nth patient, in which n was based on expected total number of procedures at that center during the study period. MAIN OUTCOME MEASURES: Intraoperative and postoperative arrhythmias, the need for cardiopulmonary resuscitation (CPR), cardiac death, and death due to any cause prior to discharge, by preoperative serum potassium level. RESULTS: Perioperative arrhythmias occurred in 1290 (53.7%) of 2402 patients, with 238 patients (10.7%) having intraoperative arrhythmias, 329 (13.7%) having postoperative nonatrial arrhythmias, and 865 (36%) having postoperative atrial flutter or fibrillation. The incidence of adverse outcomes was 3.6% for death, 2.0% for cardiac death, and 3.5% for CPR. Serum potassium level less than 3.5 mmol/L was a predictor of serious perioperative arrhythmia (odds ratio [OR], 2.2; 95% confidence interval [CI], 1.2-4.0), intraoperative arrhythmia (OR, 2.0; 95% CI, 1.0-3.6), and postoperative atrial fibrillation/flutter (OR, 1.7; 95% CI, 1.0-2.7), and these relationships were unchanged after adjusting for confounders. The significant univariate association between increased need for CPR and serum potassium level less than 3.3 mmol/L (OR, 3.3; 95% CI, 1.2-9.5) and greater than 5.2 mmol/L (OR, 3.0; 95% CI, 1.1-8.7) became nonsignificant after adjusting for confounders. CONCLUSIONS: Perioperative arrhythmia and the need for CPR increased as preoperative serum potassium level decreased below 3.5 mmol/L. Although interventional trials are required to determine whether preoperative intervention mitigates these adverse associations, preoperative repletion is low cost and low risk, and our data suggest that screening and repletion be considered in patients scheduled for cardiac surgery.
Aged↗
Anesthetic implications of new surgical approaches to myocardial revascularization.
New surgical techniques for bypassing coronary artery lesions are being explored with the goals of avoiding cardiopulmonary bypass, minimizing disfiguring scars, and decreasing hospital stay and costs. These forms of cardiac surgery have significant anesthetic implications. Intraoperatively there is an obligatory period of myocardial ischemia, which may lead to significant hemodynamic consequences. Postoperative trends towards early extubation and patient mobilization require anesthetic techniques that facilitate rapid recovery.
Journal Article↗
Testing for mutations of the ataxia telangiectasia gene in radiosensitive breast cancer patients.
BACKGROUND AND PURPOSE: To determine if clinical radiosensitivity in breast cancer patients is related to mutations of the ataxia telangiectasia gene (ATM). MATERIALS AND METHODS: Fifteen patients who had developed a severe late reaction to a standard radiotherapy schedule were examined for evidence of increased in vitro radiosensitivity using the MTT assay. Mutation analysis was performed using a protein truncation assay. RESULTS: No mutations were detected in the 15 patients despite evidence of increased in vitro radiosensitivity. CONCLUSIONS: Testing for the ATM gene is unlikely to be useful for predicting clinical response to radiotherapy in breast cancer patients.
Ataxia Telangiectasia↗
Radiosensitive melanoma cell line with mutation of the gene for ataxia telangiectasia.
The human melanoma cell lines MM96L, A2058 and HT144 were examined for sensitivity to ionizing radiation and UVB radiation. HT144 demonstrated a significant increase in sensitivity to ionizing and UVB radiation compared with the MM96L and A2058 cells. Sensitivity to both agents was associated with susceptibility to apoptosis. Using a protein truncation assay, a mutation for the gene for ataxia telangiectasia (ATM) was identified in HT144 cells. This was confirmed to be a homozygous mutation by subsequent sequencing of the abnormal region. Protein truncation assay of the other two cell lines showed no abnormality. The results suggest that somatic mutation of the A-T gene may be important in determining tumour radiosensitivity.
Apoptosis↗
Comparison of the performance of normal individuals and survivors of traumatic brain injury on repeat administrations of the Wisconsin Card Sorting Test.
Repeat administrations of the Wisconsin Card Sorting Test (WCST) are a common clinical practice to assess changes in cognitive functions of individuals recovering from traumatic brain injury (TBI). Yet, little is even known about the performance of healthy individuals on repeat administrations of the test. The present study compared the effects of repeat administration of the WCST in normal individuals and survivors of traumatic brain injury. Normal participants were administered the WCST twice, with a 5-month interval between testings and the findings were compared to the data from patients with TBI tested twice. Normal controls only modestly improved their performance on repeat testing. In contrast, using a reliability of change (RC) index, TBI survivors demonstrated clinically meaningful gains in performance.
Adult↗
Population pharmacokinetics of midazolam administered by target controlled infusion for sedation following coronary artery bypass grafting.
BACKGROUND: Midazolam is commonly used for short-term postoperative sedation of patients undergoing cardiac surgery. The purpose of this multicenter study was to characterize the pharmacokinetics and intersubject variability of midazolam in patients undergoing coronary artery bypass grafting. METHODS: With institutional review board approval, 90 consenting patients undergoing coronary artery bypass grafting were enrolled at three study centers. All subjects received sufentanil and midazolam via target-controlled infusions. After operation, midazolam was titrated to maintain deep sedation for at least 2 h. It was then titrated downward to decrease sedation for a minimum of 4 h more and was discontinued before tracheal extubation. Arterial blood samples were taken throughout the study and were assayed for midazolam and 1-hydroxymidazolam. Midazolam population pharmacokinetic parameters were estimated using NONMEM. Cross-validation was used to estimate the performance of the model. RESULTS: The pharmacokinetics of midazolam were best described by a simple three-compartment mammillary model. Typical pharmacokinetic parameters were V1 = 32.2 l, V2 = 53 l, V3 = 245 l, Cl1 = 0.43 l/min, Cl2 = 0.56 l/min, and Cl3 = 0.39 l/min. The calculated elimination half-life was 15 h. The median absolute prediction error was 25%, with a bias of 1.4%. The performance in the cross-validation was similar. Midazolam metabolites were clinically insignificant in all patients. CONCLUSIONS: The intersubject variability and predictability of the three-compartment pharmacokinetic model are similar to those of other intravenous anesthetic drugs. This multicenter study did not confirm previous studies of exceptionally large variability of midazolam pharmacokinetics when used for sedation in intensive care settings.
Adult↗
Population pharmacodynamics of midazolam administered by target controlled infusion in SICU patients after CABG surgery.
BACKGROUND: Midazolam is used commonly for sedation in the surgical intensive care unit. A suboptimal dosing regimen may lead to relative overdosing, which could result in delayed extubation and increased cost. This multicenter trial characterized midazolam pharmacodynamics in patients recovering from coronary artery bypass grafting. METHODS: Three centers enrolled 90 patients undergoing coronary artery bypass grafting. All patients received sufentanil and midazolam via target-controlled infusion. After surgery, midazolam was titrated to a Ramsay sedation score of 5 for 2 h and then decreased to maintain a sedation score of 3 or 4 for at least another 4 h. Pharmacodynamic parameters were derived using NONMEM. The model was cross-validated to test performance. RESULTS: The probability of a given level of sedation was related to the midazolam concentration by this equation: P(Sedation > or = ss) = Cn/(Cn + C(50,ss)n), where ss is the sedation score, C is the sum of the midazolam concentration and a term reflecting the dissipating effect of anesthesia: C = [midazolam] + theta x e(-Kt), where theta = 256 ng/ml and K = 0.19 h(-1). C(50,ss) values for Ramsay scores of 2 to 6 were 5.7, 71, 171, 260, and 659 ng/ml, respectively. The model predicted 57% of the data points correctly and 88% within one sedation score. CONCLUSIONS: Despite previous reports of high interindividual variability in midazolam pharmacodynamics in patients in the surgical intensive care unit, these cross-validation results suggest that, when midazolam is administered using a target-controlled infusion device, the level of sedation can be predicted within 1 sedation score in 88% of patients based on the target midazolam concentration and the time since the conclusion of the anesthetic.
Adult↗
Patient perceived health status, hospital length of stay, and readmission after coronary artery bypass surgery.
This study evaluates the effect of length of stay and baseline health status on health status and readmission rates 3 months after coronary artery bypass graft surgery. Baseline health status showed a trend toward worse scores for patients who were readmitted. Readmitted patients had longer lengths of stay, and worse 3-month health status scores, and women and patients with heart failure had higher readmission rates. It may be possible to identify patients at risk for readmission using clinical variables, length of stay, and health status. If a predictive model can be developed, then interventions can be developed and tested to decrease the rate of unplanned readmissions.
Adult↗
Cellular localisation of the ataxia-telangiectasia (ATM) gene product and discrimination between mutated and normal forms.
The recently cloned gene (ATM) mutated in the human genetic disorder ataxia-telangiectasia (A-T) is involved in DNA damage response at different cell cycle checkpoints and also appears to have a wider role in signal transduction. Antibodies prepared against peptides from the predicted protein sequence detected a approximately 350 kDa protein corresponding to the open reading frame, which was absent in 13/23 A-T homozygotes. Subcellular fractionation, immunoelectronmicroscopy and immunofluorescence showed that the ATM protein is present in the nucleus and cytoplasmic vesicles. This distribution did not change after irradiation. We also provide evidence that ATM protein binds to p53 and this association is defective in A-T cells compatible with the defective p53 response in these cells. These results provide further support for a role for the ATM protein as a sensor of DNA damage and in a more general role in cell signalling, compatible with the broader phenotype of the syndrome.
Antibodies↗