Search PubMed⌕ Search

Biomedical subjects

J M Thompson

Publications and source records attributed to J M Thompson.

At least 109 records · Page 6Linked to original sources

Maximizing vocational outcome after brain injury: integration of medical and vocational hospital-based services.

OBJECTIVE: To describe a medical and vocational case-management system that has been implemented at the Mayo Medical Center in Rochester, Minnesota, to decrease the time between onset of brain injury and successful community reintegration. DESIGN: Barriers to employment are identified and targeted as part of a system that integrates medical center- and community-based services. MATERIAL AND METHODS: The success of the project will be determined by several sources, including the Mayo-Portland Adaptability Inventory, a vocational rating scale, and traditional measures of vocational success (for example, level of independent living, job type and setting, rate of pay, and the type and cost of vocational supports being used). Overall study outcomes will be compared against benchmarks derived from the literature on vocational outcome after brain injury. RESULTS: Preliminary data are encouraging that project goals are attainable. The medical case-management system has decreased the amount of time between injury and initiation of vocational and other rehabilitation services. During the first year, 67 persons with brain injury began receiving vocational services through the project, and 34% are in community-based nonsheltered work or training programs. Second-year data will reveal whether the goal of 70% placement within 9 months after admission to the project can be maintained.

Activities of Daily Living↗

Phantom limb pain and chemotherapy in pediatric amputees.

OBJECTIVE: To determine the frequency of phantom limb pain in pediatric patients with cancer-related amputations and the relationship between phantom limb pain and chemotherapy (CHRx). DESIGN: We retrospectively reviewed the medical records of all pediatric patients who underwent major limb amputations between 5 and 17 years of age during the period from Oct. 1, 1983, to Oct. 1, 1993, and were treated at the Mayo Clinic. MATERIAL AND METHODS: One investigator reviewed 293 medical records and selected cases on the basis of specific inclusion and exclusion criteria. The study group consisted of 75 patients (67 with cancer-related and 8 with trauma-associated amputations). All reports of phantom limb pain and its temporal relationship to administration of CHRx were recorded. Data were analyzed by use of descriptive statistics. RESULTS: Phantom limb pain was reported in 48% of patients with cancer-related amputations in comparison with 12% of patients with trauma-associated amputations. Among patients with cancer, phantom limb pain was experienced by 74% who were exposed to CHRx before or at the time of amputation, 44% who received CHRx after amputation, and 12% who never received CHRx. Patients with trauma-related amputations and those who did not receive CHRx reported phantom limb pain at similar intervals after amputation (a mean of 6 days). In comparison, 76% of patients with cancer and a history of exposure to CHRx reported phantom limb pain within 72 hours after amputation. Three of four patients who first received CHRx after amputation reported phantom limb pain on the day CHRx was begun (a mean of 12.3 days after amputation). CONCLUSION: Our observations suggest that (1) phantom limb pain occurs more often in pediatric amputees with cancer than in those with trauma and (2) the hypothesis that CHRx may be a risk factor in the development of phantom limb pain in pediatric amputees should be investigated further.

Adolescent↗

Characterization of 5-lipoxygenase inhibitors in biochemical and functional in vivo assays.

Several potent and selective inhibitors of 5-lipoxygenase (5-LO) have been recently developed with excellent activity in certain in vivo assays of leukotriene production. The efficacy of three such inhibitors that have been in clinical trials (zileuton, A-78773 and ZD2138) were evaluated in: 1) ex vivo whole blood assay, 2) dermal Arthus reaction, and 3) functional airway response. In addition, a model of eicosanoid production in rat lung was developed that provides a simple assay for evaluation of the biochemical efficacy of 5-LO inhibitors in the lung. Bronchoalveolar lavage of rat lung with calcium ionophore A23187 resulted in rapid and robust production of PGE2, 6-keto-PGF1 alpha, thromboxane (TxB2), and leukotriene B4 (LTB4). Supplementation of lavage fluid with archidonic acid markedly augmented production of all eicosanoids except LTB4. All three inhibitors were potent and selective blockers of LTB4 production in the ex vivo whole blood assay and in the dermal Arthus reaction. In contrast, higher doses of inhibitor were needed to block LTB4 production in the rat lung lavage model than were needed to block ex vivo whole blood LTB4 production when both end points were measured in the same animal. Similarly, zileuton and A-78733 were less effective in suppressing the functional airway response to antigen in sensitized guinea pigs, whereas both inhibitors were effective in suppressing LTB4 production in the ex vivo whole blood assay. These results demonstrate that different 5-LO inhibitors have markedly distinct efficacy for inhibition of leukotriene production, depending on the animal model.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Human monoclonal anti-D secreting heterohybridomas from peripheral B lymphocytes expanded in the CD40 system.

Peripheral human B lymphocytes isolated from four immunised anti-D donors have been cultured in the CD40 system (Banchereau et al., 1991), prior to fusion to murine X63Ag8.653 plasmacytoma cells. High fusion efficiency was noted in all cases and immunoglobulin (IgG and IgM) was detected in nearly all heterohybrid containing wells. Only fusions using boosted donor lymphocytes generated specific anti-D secreting hybrids. A short period of culture of committed B cell precursors in the CD40 system before fusion appears to be both adequate and efficient in permitting generation of specific antibody-secreting hybrids.

Animals↗

Risk factors for small for gestational age infants: a New Zealand study. New Zealand Cot Death Study Group.

AIM: The aim was to identify risk factors for small for gestational age infants. METHOD: Case-control study. The study population was 1800 infants selected randomly from all babies born over a three year period over 78% of the country. Of these 1800 infants, 85 (4.8%) were classified as preterm (< 37 weeks completed gestation) and were excluded. 157 (8.9%) were classified as small for gestational age (cases) and 1519 (86.3%) were fullterm, nonsmall for gestational age infants (controls). Risk factors were investigated using data collected from obstetric records and parental interviews. RESULTS: Risk factors associated with small for gestational age after controlling for potential confounders included maternal smoking during pregnancy (Odds ratio (OR) 2.61, 95% confidence interval (CI) 1.65, 4.15), primiparity (OR 2.96, 95% CI 1.59, 5.48), lack of antenatal care in the first trimester (OR 1.83, 95% CI 1.13, 2.98) and young age when mother left school (OR 1.56, 95% CI 1.01, 2.41). Use of marijuana in pregnancy significantly increased risk of small for gestational age at the 6% level (OR = 1.86, 95% CI 0.98, 3.52). The population attributable risk for maternal smoking was 31.1% (95% CI 18.2, 41.9). CONCLUSION: Maternal smoking was the most important modifiable risk factor in this dataset for small for gestational age.

Adolescent↗

Sex specific birthweight percentiles by gestational age for New Zealand.

AIM: To produce sex specific percentiles by gestational age for New Zealand infants. METHODS: Gestational age (completed weeks) and birthweight (10 g multiples) was obtained for all births in New Zealand in 1990 and 1991. Outliers were identified and removed, the data was normalised at each gestational age and percentiles produced. RESULTS: The percentile charts were produced for gestational ages 24 to 44 weeks by sex of infant. There was an approximate difference of 100 g between male and female birthweight at all gestational ages. DISCUSSION: These are the first national birthweight percentile charts for New Zealand. As they may vary over time we recommend they be updated every 5 years.

Biometry↗

Measurement of human sympathetic nervous responses to stressors by microneurography.

Human sympathetic nervous responses have been extensively studied using various stressors; however, there have been few comparisons of the patterns of sympathetic nervous activation which may be produced by different stressors. The purpose of this study was to explore whether different stressors produce differing degrees of sympathetic activation in muscle vasoconstrictor nerve fibres.

Adult↗

A statistical analysis of the growth of small abdominal aortic aneurysms.

Screening for abdominal aortic aneurysm has been offered to 13,000 patients. An overall compliance of 76% (range 51-99%) has been achieved. For those with an initial aortic diameter between 29 mm and 45 mm serial ultrasound scans are offered to monitor aortic change. Of the 302 cases followed up by repeated scans, 93 have had more than 5 scans (mean of 7 scans) over a mean time period of 32.1 months (range 15-63 months). The rate of change of all these aneurysms has been calculated using all data points and robust linear regression. It has been possible to postulate an algorithm for aortic growth. The influence of measurement precision and ultrasound quality assurance on the rescan interval is demonstrated and it is suggested that 2 years is a suitable rescan interval for aortas with diameter less than 40 mm.

Aged↗

Comparison of live attenuated and inactivated influenza vaccines in cystic fibrosis patients and their families: results of a 3-year study.

Forty-one cystic fibrosis (CF) patients and 89 family members were immunized in a double-blind randomized 3-year trial with either intranasal live cold-adapted (ca) influenza A vaccine or the recommended intramuscular trivalent inactivated (triv) influenza vaccine. Local, respiratory, and systemic symptoms after vaccine were infrequent and did not differ between vaccine groups. CF patients did not differ from family members in immune response to either vaccine. Although antibody responses tended to be higher after triv vaccine, > or = 85% of subjects had mean hemagglutination inhibition antibody titers > or = 1:32 to influenza H1N1 and H3N2 after the first dose of either vaccine. Infection with influenza H3N2 viruses circulating during this study occurred with comparable low frequency in CF patients after ca (14 infections/100 subject-years of observation) or triv vaccine (10 infections/100 subject-years of observation). Influenza A ca vaccines appear to be safe, immunogenic alternatives to influenza A inactivated vaccines for CF patients and their families.

Adolescent↗

Travel and changes in routine do not increase the risk of sudden infant death syndrome.

We investigated the relationship between travel and changes in routine and the sudden infant death syndrome (SIDS) among 485 SIDS cases compared with 1800 randomly selected control infants. There was no increased risk of SIDS with travel. Special events, such as christenings, were not associated with an increased risk of SIDS. However, visits to and by friends or relatives were associated with a significantly reduced risk of SIDS after controlling for potential confounders (odds ratios = 0.70; 95% confidence interval = 0.52, 0.96). These findings may indicate less social support in SIDS cases.

Analysis of Variance↗

Risk factors for readmission to hospital for asthma in childhood.

BACKGROUND: Readmissions account for part of the increase in hospital admissions for asthma in childhood seen in many countries. METHODS: This observational study recorded demographic features and the severity, treatment and management of asthma in 1034 individual children admitted to hospital over a one year period, followed for a maximum of 33 months. RESULTS: Readmissions were common, with 33% readmitted by six months and 51% by two years. After controlling for a wide range of variables, factors that significantly increased readmission were: female sex (relative risk (RR) 1.23; 95% confidence interval (CI) 1.03 to 1.46), young age (age < 5 years RR 1.71; 95% CI 1.41 to 2.08), number of previous admissions (one previous admission RR 1.32; two, RR 1.68; three, RR 2.00; four or more, RR 2.80), and inpatient intravenous treatment (RR 1.29; 95% CI 1.08 to 1.55). Inpatient treatment with theophylline was used frequently (98.4%), but was associated with decreased readmissions (RR 0.51, 95% CI 0.28 to 0.92). Factors which did not predict readmission included ethnicity, respiratory and pulse rate, medical team, prescribed prophylactic treatment, type of follow up, or the use of action plans. CONCLUSIONS: Risk factors for readmission relate to the characteristics of the individual (age and sex), severity of the condition (intravenous treatment), and number of previous admissions which may reflect severity or behaviour of the illness. Medical treatment and management did not influence readmissions. Strategies to reduce the high readmission rate for asthma in childhood need to be developed.

Age Distribution↗

Heart rate spectral analysis, cardiac norepinephrine spillover, and muscle sympathetic nerve activity during human sympathetic nervous activation and failure.

BACKGROUND: Although heart rate variability (HRV) at 0.1 Hz has been proposed as a noninvasive clinical measure of cardiac sympathetic nerve firing, this premise has not been sufficiently validated by comparison with techniques such as microneurography and the measurement of norepinephrine spillover from the heart that more directly reflect presynaptic sympathetic activity. METHODS AND RESULTS: We compared the three techniques under conditions of effective cardiac sympathetic denervation, pure autonomic failure (n = 4), dopamine beta-hydroxylase deficiency (n = 1), and after cardiac transplantation (n = 9) as well as in the context of sympathetic nervous activation in cardiac failure (n = 15) and with aging (n = 10). Age-matched comparisons were made in each case with healthy individuals drawn from a pool of 52 volunteers. In pure autonomic failure and early after transplantation, cardiac norepinephrine spillover was negligible, and HRV was low. Late after transplantation, however, cardiac norepinephrine spillover returned to normal levels, and HRV remained low. In comparison to younger subjects (18 to 35 years old), older individuals (60 to 75 years old) had higher muscle sympathetic nerve activity (young, 22.9 +/- 1.9; old, 31.3 +/- 5.8 bursts per minute; P < .05) and cardiac norepinephrine spillover (young, 14.3 +/- 2.5; old, 20.1 +/- 3.0 ng/min; P < .05). In contrast, total HRV was reduced by 89%, and at 0.1 Hz it was reduced by 93% (P < .05). Cardiac failure was also characterized by elevated cardiac norepinephrine spillover (cardiac failure patients, 59 +/- 4; healthy volunteers, 18 +/- 3 ng/min; P < .01) but reduced 0.1 Hz HRV (cardiac failure patients, 49 +/- 17; healthy volunteers, 243 +/- 4 ms2; P < .05). CONCLUSIONS: HRV at 0.1 Hz depends on factors in addition to cardiac sympathetic nerve firing rates, including multiple neural reflexes, cardiac adrenergic receptor sensitivity, postsynaptic signal transduction, and electrochemical coupling, and is not directly related to cardiac norepinephrine spillover, which is a more direct measure of the sympathetic nerve firing rate.

Adolescent↗

Clinical evaluation of sodium ion selective field effect transistors for whole blood assay.

Sodium ion selective field effect transistors (ISFETs) were evaluated for their performance in measurement of sodium ions in whole blood for 'near patient' analysis in operating theatres and intensive care units. Performance was evaluated in comparison with a standard clinical laboratory sodium/potassium ion analyser (Radiometer KNA1) and with sodium and potassium assays using flame photometry on the plasma from each whole blood specimen. The imprecisions (coefficients of variation) of three ISFETs for sodium ion assay were 1.08, 1.56 and 1.10%, respectively. Robust bivariate linear regression (reweighted least squares preceded by least median of squares) of the ISFET versus KNA1 sodium ion activity yielded a regression coefficient of 1.08 and an intercept of -18.2 mM. The influence of potassium, protein and lipid on the measurement of sodium ions by both ISFETs and the KNA1 was assessed using robust multiple regression (also based on reweighted least squares preceded by least median of squares). In the regression versus flame photometry, protein was found to be more influential for the KNA1 (glass sodium ion selective electrode) than for the ISFET. Potassium had no influence on assays using the ISFET, but had a weak negative influence on assays using the KNA1. Two ISFETs lasted for more than 200 assays each demonstrating their robustness in the assay of whole blood.

Blood Chemical Analysis↗

Prevalence of abdominal aortic aneurysm associated with hypertension in an urban population.

SETTING AND METHOD: Since 1989 13,000 invitations to screening for abdominal aortic aneurysm have been offered to men aged 60 to 75 living within the Birmingham conurbation. RESULTS: The overall attendance was 76.1% (52-99%). The prevalence of aneurysms greater than 29 mm in the whole male population aged 60 to 75 was 7.2%. For those aged 60 to 64 the prevalence was 3.8%. For those aged between 60 and 64 with hypertension, however, the prevalence of abdominal aortic aneurysm was 7.7%. The relative risk of hypertension associated with aneurysm disease is 2.7. CONCLUSIONS: This paper suggests that all men over 65 should be screened for aortic aneurysm, but that those men over 60 with hypertension should be added to the screened cohort.

Age Factors↗

Postnatal depression in a community cohort.

A community cohort of 206 European and Maori women completed a questionnaire screening for postnatal depression at 4 weeks postpartum. The prevalence of major depressive disorder amongst the women was 7.8% with a further 13.6% of women experiencing more minor depressive symptoms. Postnatal depression was more likely to occur in women who were single, were less than 20 years old at the birth of their first child, were unhappy with their relationship with their partner, had a history of previous psychiatric hospitalisation, and were Maori. Women who were depressed were more likely to show a lack of enjoyment of and less positive attitude towards their infant. The study highlights the value of screening for postnatal depression with a simple questionnaire, as few depressed women would have been otherwise recognised.

Adolescent↗

Bed sharing, smoking, and alcohol in the sudden infant death syndrome. New Zealand Cot Death Study Group.

OBJECTIVES: To investigate why sharing the bed with an infant is a not consistent risk factor for the sudden infant death syndrome in ethnic subgroups in New Zealand and to see if the risk of sudden infant death associated with this practice is related to other factors, particularly maternal smoking and alcohol consumption. DESIGN: Nationwide case-control study. SETTING: Region of New Zealand with 78% of all births during 1987-90. SUBJECTS: Home interviews were completed with parents of 393 (81.0% of total) infants who died from the sudden infant death syndrome in the postneonatal age group, and 1592 (88.4% of total) controls who were a representative sample of all hospital births in the study region. RESULTS: Maternal smoking interacted with infant bed sharing on the risk of sudden infant death. Compared with infants not exposed to either risk factor, the relative risk for infants of mothers who smoked was 3.94 (95% confidence interval 2.47 to 6.27) for bed sharing in the last two weeks and 4.55 (2.63 to 7.88) for bed sharing in the last sleep, after other confounders were controlled for. The results for infants of non-smoking mothers were inconsistent with the relative risk being significantly increased for usual bed sharing in the last two weeks (1.73; 1.11 to 2.70) but not for bed sharing in the last sleep (0.98; 0.44 to 2.18). Neither maternal alcohol consumption nor the thermal resistance of the infant's clothing and bedding interacted with bed sharing to increase the risk of sudden infant death, and alcohol was not a risk factor by itself. CONCLUSION: Infant bed sharing is associated with a significantly raised risk of the sudden infant death syndrome, particularly among infants of mothers who smoke. The interaction between maternal smoking and bed sharing suggests that a mechanism involving passive smoking, rather than the previously proposed mechanisms of overlaying and hyperthermia, increases the risk of sudden infant death from bed sharing.

Adult↗

Medical direction and control of emergency medical services in Canada.

OBJECTIVE: To determine the level of physician involvement in prehospital emergency medical services (EMS) in Canada, as compared with published principles of medical control and direction. DESIGN: Mail and telephone survey by means of a questionnaire from March to November 1991. SETTING: All Canadian provinces and territories. PARTICIPANTS: Fifty-six key prehospital EMS physicians, senior government administrators and senior representatives of the agencies responsible for licensing physicians in each province or territory. MAIN OUTCOME MEASURES: Responses to questions regarding the legislation, organization, administration, practice and regulation of medical direction and control by physicians in each province or territory. RESULTS: EMS legislation describing medical direction and control was completely lacking in five provinces and both territories and was incomplete in the remainder. Provincial guidelines written by physicians for prehospital patient care were present in only four provinces. Formal organization of medical directors varied from none to partially remunerated networks. Regional medical-director systems were present in three provinces, and local medical directors were required for all communities in three. Most rural ambulance services were found to engage physicians only when there was local interest. CONCLUSIONS: The level of physician involvement in the medical direction and control of EMS appears to be inconsistent across Canada and insufficient in most jurisdictions, as compared with accepted principles.

Allied Health Personnel↗