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Biomedical subjects

J Barton

Publications and source records attributed to J Barton.

At least 37 records · Page 2Linked to original sources
PubMed1998

Painless small bowel ischemia presenting with diarrhea and weight loss.

Chronic ischemia of the small bowel is classically described as presenting with abdominal pain associated with eating (intestinal angina). Here we describe the cases of two patients with chronic small bowel ischemia who presented atypically with painless watery diarrhea and weight loss. These cases suggest that the clinical spectrum of chronic small bowel ischemia may be wider than previously appreciated. Chronic ischemia of the small bowel should be included in the differential diagnosis for painless watery diarrhea in the context of weight loss.

Aged↗
PubMed1998

The emotional impact of shift work on the children of shift workers.

OBJECTIVES: This study compared the emotional state of children of shift and day working fathers. METHODS: One hundred and ninety children (8 to 11 years of age) took part in the study. Ninety-one came from "shift working" homes, and 99 came from "day working" homes. Each child completed 2 questionnaires, The Harter Self-Perception Questionnaire and the Children's Depression Inventory. RESULTS: The daughters of shift working fathers reported a significantly poorer perception of their ability in school-related activities and significantly greater discrepancies between their perceived overall level of competence and their ideal level of competence. In addition, more depressive symptomatology and a lower level of self-esteem were also found for the daughters of shift working fathers in comparison with the daughters of day working fathers. No such effects were found for the sons of shift working fathers. CONCLUSIONS: Parental shift working may be experienced as stressful within the family, and this stress may affect the emotional state of the child. However, the nature of expression of these emotional difficulties may vary according to the gender of the child. Further research is needed.

Child↗
PubMed1997

Anionic- and lipophilic-mediated surface binding inhibitors of human leukocyte elastase.

We report the synthesis of a series of diphenylmethane-based oligomers containing anionic and lipophilic functionalities that are potent inhibitors of human leukocyte elastase (HLE). The enzyme inhibition is regulated by the size of the oligomer, as well as, the number of charges. Lipophilicity is an important element in determining potency and specificity against other basic enzymes. Compounds whose scaffolds contain three phenoxyacetic acid groups and three alkyl ethers are competitive and specific inhibitors of HLE with Ki = 20 nM. The mechanism of action of this class of compounds is believed to involve multidendate interactions with the surface of HLE near the active site which prevents substrate access to the catalytic site.

Benzhydryl Compounds↗
PubMed1997

The effect of norepinephrine on insulin secretion and glucose effectiveness in non-insulin-dependent diabetes.

It has previously been shown that in normal subjects, physiological elevation of norepinephrine (NE) impairs insulin sensitivity (Si) but does not influence insulin secretion. The aim of this study was to determine the effect of short-term physiological elevation of NE on insulin secretion, Si, and glucose-mediated glucose disposal, or the glucose effectiveness index (Sg), in non-insulin-dependent diabetes mellitus (NIDDM). Two intravenous glucose tolerance tests (IVGTTs) were performed in eight well-controlled NIDDM patients, using a supplemental exogenous insulin infusion to achieve an approximation of normal endogenous insulin secretion. The IVGTTs were performed in random order after 30 minutes of either the saline (SAL) or NE (25 ng/kg/min) infusions, which were continued throughout the 3-hour IVGTT. Sg and Si were estimated by minimal model analysis of the IVGTT data as previously described. Plasma C-peptide was used to estimate insulin secretion rate using the ISEC program. NE infusion produced approximately a threefold increase in plasma NE, associated with (1) a significant reduction in glucose disposal ([KG] SAL v NE, 0.73 +/- 0.06 v 0.61 +/- 0.06 x 10(-2).min-1, P < .05), (2) no reduction in Si (2.33 +/- 0.8 v 2.62 +/- 0.9 x 10(-4).min-1/mU/L, NS), (3) a reduced mean second-phase insulin secretion rate (1.21 +/- 0.19 v 1.01 +/- 0.16 x 10(-3) pmol/kg/min per mmol/L glucose, P < .05), (4) a significant increase in Sg (0.89 +/- 0.08 v 1.63 +/- 0.2 x 10(-2).min-1, P < .05), and (5) a corresponding increase in glucose effectiveness at zero insulin ([GEZI] 0.55 +/- 0.13 v 1.30 +/- 0.33 x 10(-2).min-1, P < .05). These results show that in contrast to normal subjects, physiological elevation of NE in NIDDM does not result in a reduction in Si, but causes a reduction in glucose disposal related to inhibition of insulin secretion that is only partially compensated for by increased Sg.

Adult↗
PubMed1997

Suicide prevention in New South Wales Correctional Centres.

The New South Wales Department of Corrective Services has introduced a number of suicide prevention measures in order to deal with the problem of inmate suicides. This article describes the measures. The article also shows that the characteristics of the incarcerated population differ greatly from those in the community. Findings from the self-harm database 1991-1995 show that, nevertheless, there are some unique characteristics of the group of self-harmers and fatal self-harmers. These findings are discussed in relation to the preventive measures that are introduced in the NSW correctional centers.

Adult↗
PubMed1997

Road traffic accidents: early psychological consequences in children and adolescents.

BACKGROUND: Although road traffic accidents are a major cause of injury and death in children and adolescents, research into their psychological consequences consists mainly of case reports. METHOD: A prospective study was made of young road traffic accident victims: 57 subjects, aged 5-18 years, who had been injured in road traffic accidents, and their parents, were interviewed 2-16 days post-accident and re-examined after 12-15 weeks. RESULTS: Post-accident stress symptoms occurred at both times. There was a decrease of symptom severity between the two interviews, but at the later time, 14% still suffered from moderate or severe post-traumatic stress disorder, 17% from serious traffic-related fears, and parents reported increased mood disturbance in their children compared with the pre-accident period. High levels of distress during and immediately after the accident were associated with severe post-traumatic stress symptoms. CONCLUSIONS: There is an urgent need for healthcare staff working with children and adolescents involved in road traffic accidents to be aware of the potential psychological consequences and the importance of the immediate accident experience on subsequent coping.

Accidents, Traffic↗
PubMed1996

Characterization of the catecholamine extraneuronal uptake2 carrier in human glioma cell lines SK-MG-1 and SKI-1 in relation to (2-chloroethyl)-3-sarcosinamide-1-nitrosourea (SarCNU) selective cytotoxicity.

Transport of (2-chloroethyl)-3-sarcosinamide-1-nitrosourea (SarCNU) and (-)-norepinephrine was investigated in SarCNU-sensitive SK-MG-1 and -resistant SKI-1 human glioma cell lines. [3H]SarCNU influx was inhibited by SarCNU, sarcosinamide, and (+/-)-epinephrine in SK-MG-1 cells with competitive inhibition observed by (+/-)-epinephrine (Ki = 140 +/- 12 microM) and (+/-)-norepinephrine (Ki = 255 +/- 41 microM). No effect on influx was detected in SKI-1 cells. [3H](-)-Norepinephrine influx was linear to 15 sec in both cell lines and temperature dependent only in SK-MG-1 cells. Influx of [3H](-)-norepinephrine was found to be saturable in SK-MG-1 (K(m) = 148 +/- 28 microM, Vmax = 1.23 +/- 0.18 pmol/microL intracellular water/sec) but not in SKI-1 cells. In SK-MG-1 cells, [3H](-)-norepinephrine influx was found to be inhibited competitively by (-)-epinephrine (Ki = 111 +/- 7 microM) and SarCNU (Ki = 1.48 +/- 0.22 mM). Ouabain and KCl were able to inhibit the [3H](-)-norepinephrine influx in SK-MG-1 cells, consistent with influx being driven by membrane potential. Several catecholamine uptake2 inhibitors were able to reduce significantly the influx of [3H](-)-norepinephrine and [3H]SarCNU with no inhibition by a catecholamine uptake1 inhibitor. These findings suggest that increased sensitivity of SK-MG-1 to SarCNU is secondary to enhanced accumulation of SarCNU mediated via the catecholamine extraneuronal uptake2 transporter, which is not detectable in SKI-1 cells. The introduction of SarCNU into clinical trials will confirm if increased uptake via the catecholamine extraneuronal uptake2 transporter will result in increased antitumor activity.

Antineoplastic Agents↗
PubMed1996

Variations in the management and survival of women under 50 years with breast cancer in the South East Thames region.

A retrospective, population-based study was undertaken to determine variations in the management of women aged less than 50 years with primary breast cancer in different hospital settings and the influence of these variations on survival. A total of 1757 women who were resident in the South East Thames Health Region aged less than 50 years at the time of diagnosis of breast cancer and who presented during a 5 year period (January 1984 to December 1988) were recorded by the Thames Cancer Registry. The hospitals at which primary surgery was undertaken were categorised as teaching or non-teaching hospitals. The non-teaching hospitals were grouped according to the mean number of patients treated annually during the study period (< or = 2, 3-9, > or = 10 each year). The following factors were compared between these groups: age, extent of disease, tumour morphology, extent of primary surgery (mastectomy vs less than mastectomy), use of axillary surgery (any vs none) and use of systemic adjuvant therapy. Survival rates for the different groups were compared. Registration rates did not differ significantly between health districts. A total of 1485 (85%) women underwent surgery in over 90 different hospitals. In 1324 (86%) of these cases the surgery was undertaken in a total of 42 NHS hospitals within SE Thames Health Region or in seven teaching hospitals in adjacent regions. Mastectomy rates decreased from 52% in 1984 to 28% in 1988 (P<0.0001), but were consistently higher in teaching hospitals (P=0.01). The use of any form of axillary surgery decreased from 49% to 36% over the 5 year period (P=0.003), with significantly lower rates of axillary surgery being performed in non-teaching hospitals (P<0.0001). The proportion of cases recorded as having non-specific morphology was higher in nonteaching than in teaching hospitals (P<0.0001). On multivariate analysis survival was significantly (P<0.001) influenced by stage and tumour histology. Among patients who underwent surgery, the type of hospital in which this was undertaken did not appear to influence survival significantly. This analysis of routine cancer registry data indicates that patients were widely dispersed in a large number of different hospitals and that there were marked variations in practice according to the type of hospital to which patients presented. The treatments provided were frequently at variance with those recommended at a consensus conference held during the study period, particularly in relation to the use of axillary surgery and adjuvant systemic therapy. The way in which services are currently provided may hamper the delivery of appropriate management and comprehensive support. These data thus have implications for the purchasing and provision of services for this common condition.

Adult↗
PubMed1996

Comparison of eight and 12 hour shifts: impacts on health, wellbeing, and alertness during the shift.

OBJECTIVES: The generally agreed view is that there is no ideal shift system, and that most systems will have both advantages and disadvantages. As such, attention has been placed on trying to identify good and bad features of shift systems, with a view to minimising the possible ill health as a consequence of shiftwork. The present study focuses on the duration of the shift and looks at the implications for individual health, wellbeing, and alertness during the shift of extending the shift from the traditional eight hours to 12. METHODS: Two groups of chemical workers, one working 12 hour shifts and the other working eight hour shifts, took part. All completed a modified version of the standard shiftwork index (SSI), a set of self reported questionnaires related to health and wellbeing. RESULTS: The two groups did not differ on most outcome measures, although the differences that did exist suggested advantages for the 12 hour shift workers over the eight hour shift workers; with the notable exception of rated alertness at certain times of day. CONCLUSIONS: The results are explained in terms of the design of the 12 hour shift system and the specific sequencing of shifts that seem to minimise the potential for the build up of fatigue. Although the current data moderately favour 12 hour shifts, a cautionary note is sounded with regard to the implications of the alertness ratings for performance and safety.

Adult↗
PubMed1995

Cigarette smoking, tar yields, and non-fatal myocardial infarction: 14,000 cases and 32,000 controls in the United Kingdom. The International Studies of Infarct Survival (ISIS) Collaborators.

OBJECTIVES: To assess the effects of cigarette smoking on the incidence of non-fatal myocardial infarction, and to compare tar in different types of manufactured cigarettes. METHODS: In the early 1990s responses to a postal questionnaire were obtained from 13,926 survivors of myocardial infarction (cases) recently discharged from hospitals in the United Kingdom and 32,389 of their relatives (controls). Blood had been obtained from cases soon after admission for the index myocardial infarction and was also sought from the controls. 4923 cases and 6880 controls were current smokers of manufactured cigarettes with known tar yields. Almost all tar yields were 7-9 or 12-15 mg/cigarette (mean 7.5 mg for low tar (< 10 mg) and 13.3 for medium tar (> or = 10 mg). The cited risk ratios were standardised for age and sex and compared myocardial infarction rates in current cigarette smokers with those in non-smokers who had not smoked cigarettes regularly in the past 10 years. RESULTS: At ages 30-49 the rates of myocardial infarction in smokers were about five times those in non-smokers (as defined); at ages 50-59 they were three times those in non-smokers, and even at ages 60-79 they were twice as great as in non-smokers (risk ratio 6.3, 4.7, 3.1, 2.5, and 1.9 at 30-39, 40-49, 50-59, 60-69, 70-79 respectively; each 2P < 0.00001). After standardisation for age, sex, and amount smoked, the rate of non-fatal myocardial infarction was 10.4% (SD 5.4) higher in medium tar than in low tar cigarette smokers (2P = 0.06). This percentage was not significantly greater at ages 30-59 (16.6% (7.1)) than at 60-79 (1.0% (8.5)). In both age ranges the difference in risk between cigarette smokers and non-smokers was much larger than the difference between one type of cigarette and another (risk ratio 3.39 and 3.95 at ages 30-59 for smokers of similar numbers of low and of medium tar cigarettes, and risk ratio 2.35 and 2.37 at ages 60-79). Most possible confounding factors that could be tested for were similar in low and medium tar users, with no significant differences in blood lipid or albumin concentrations. CONCLUSION: The present study indicates that the imminent change of tar yields in the European Union to comply with an upper limit of 12 mg/cigarette will not increase (and may somewhat decrease) the incidence of myocardial infarction, unless they indirectly help perpetuate tobacco use. Even low tar cigarettes still greatly increase rates of myocardial infarction, however, especially among people in their 30s, 40s, and 50s, and far more risk is avoided by not smoking than by changing from one type of cigarette to another.

Adult↗
PubMed1995

Recovery from work shifts: how long does it take?

Although regulations on work hours usually include a minimum weekly rest period, there is little empirical evidence concerning recovery from work. Shift-working nurses (N = 61) used a handheld computer for 28 days to complete self-ratings, cognitive-performance tasks, and a sleep diary. Many measures were worse on rest days that followed a night shift rather than a day shift and tended to be worse on first rest days compared with subsequent rest days. Alertness was lowest on the 1st rest day following a night shift. Social satisfaction was better on workdays that were preceded by 2 rather than 1 rest day. Reaction time decreased over consecutive night shifts and tended to increase over rest days following night shifts. The results are interpreted as being consistent with the combined adaptive costs of fatigue and adjustment to and from a nocturnal routine. The practical implications for scheduling rest days are considered.

Adult↗
PubMed1995

The use of survey measures to assess circadian variations in alertness.

Current models of sleep regulation postulate both a homeostatic and circadian component and promise an understanding of disturbed and displaced sleep. Estimates of these components have traditionally required relatively cumbersome and costly measures, including sleep electroencephalograms and continuously recorded rectal temperature, but it has recently been demonstrated that they may successfully be based on frequent (e.g. 2-hourly) concurrent ratings of alertness. This paper examines whether similar results might be obtained using retrospective survey measures of alertness obtained from shiftworking nurses at a single sitting. These retrospective measures are shown to be sensitive to both time of day and shift, to have a high level of reliability even for relatively small sample sizes (e.g. 10) and to be valid predictors of more traditional concurrent measures of alertness. It is concluded that retrospective alertness ratings may prove to be an extremely cost-effective method for examining the trends in alertness in various groups, including those suffering from specific types of sleep disorder.

Adult↗
PubMed1995

Complications of fat grafting to the penis.

Fat grafting to the penis has recently become popular in some parts of the country. Surgery is commonly performed in the office, where peer review is lacking or nonexistent. A single case is reported documenting a poor cosmetic and functional result after irregular resorption of grafted fat. The external appearance of the penis remained stable for months, even though later biopsy revealed all the grafted fat to be dead. Analogy with pseudolipoma of Glisson's capsule is provided, showing that dead fat cells can survive for years or even a lifetime without absorption by the body. Several complications are examined in this article, and other potential risks are also discussed. The operation, although technically easy to perform, has many serious potential side effects that should be understood.

Adipose Tissue↗
PubMed1995

Improved prediction of bone mineral content and density.

To establish improved predictive values for normal bone mineral content (BMC) and density (BMD) in adolescent girls a community based study of schoolgirl volunteers was carried out by dual energy x ray absorptimetry. Measurements were performed on 216 subjects aged 11.0 to 17.9 years; measurements were repeated one year later on 84 of the girls, providing a total of 300 studies. For total body BMC the standard error of the prediction was improved from 290.9 g to 134.1 g when weight, height, and shoulder width were added to the normal variable of age. For spine BMD the standard error of the prediction was improved from 0.105 g/cm2 to 0.066 g/cm2 when height, weight, and shoulder width were added to the normal variable of age. Significant improvements were also obtained for total BMD and spine BMC. Despite the normal practice of predicting bone density from age alone this was not selected as the first variable in a multiple stepwise regression for either total body or spine. The prediction of BMC and BMD can be significantly improved by the inclusion of simple body habitus parameters in the prediction equations. As the mean (SE) z score derived from the manufacturer's normal data was - 0.36 (0.02) these American data are probably not appropriate for use in adolescents in the UK.

Absorptiometry, Photon↗
PubMed1994

A population study of food intolerance.

We did a population study to identify the prevalence of reactions to eight foods commonly perceived to cause sensitivity in the UK. A cross-sectional survey of 7500 households in the Wycombe Health Authority area and the same number of randomly-selected households nationwide was followed up by interviews of positive respondents from the Wycombe Health Authority area. Those who agreed entered a double-blind, placebo-controlled food challenge study to confirm food intolerance. 20.4% of the nationwide sample and 19.9% of the High Wycombe sample complained of food intolerance. Of the 93 subjects who entered the double-blind, placebo-controlled food challenge, 19.4% (95% confidence interval 11.4%-27.4%) had a positive reaction. The estimated prevalence of reactions to the eight foods tested in the population varied from 1.4% to 1.8% according to the definition used. Women perceived food intolerance more frequently and showed a higher rate of positive results to food challenge. There is a discrepancy between perception of food intolerance and the results of the double-blind placebo-controlled food challenges. The consequences of mistaken perception of food intolerance may be considerable in financial, nutritional, and health terms.

Adolescent↗
PubMed1994

Choosing to work at night: a moderating influence on individual tolerance to shift work.

The author looked at the impact of choosing to work at night on individual tolerance to shift work. The relative importance of individual circumstances and personality type in influencing this decision was examined. Five hundred eighty-seven nurses and midwives completed measures of physical and psychological health, difficulties with sleep, social and domestic disruption, flexibility of sleeping habits, morning versus evening preferences, and reasons for engaging in shift work. Results high-lighted the advantages of choosing to work at night, rather than engaging in night work as part of a rotating-shift schedule, on tolerance to shift work. The individual circumstances of the shift workers were particularly important in influencing whether they chose to work at night. These results offer some support for the maintenance of permanent night-shift schedules and have implications for the future design of shift systems.

Adult↗