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Biomedical subjects

J Booth

Publications and source records attributed to J Booth.

At least 55 records · Page 3Linked to original sources
PubMed1997

Decreased survival in patients with co-existent rheumatoid arthritis and bronchiectasis.

The aim was to compare the 5 yr survival in patients with rheumatoid arthritis (RA) alone, bronchiectasis (Br) alone and RA plus Br (RA-Br). A case-control study was carried out in which 32 patients with RA-Br were matched for age (within 5 yr), sex and (where possible) disease duration with 32 patients with RA alone. An additional comparison group of 31 unselected patients with Br was chosen. All patients were followed for 5 yr. Patients with RA-Br were 7.3 times more likely to die than the general population, 5.0 times more likely than the RA group and 2.4 times more likely than the Br group. An increased risk of death within the RA-Br group was associated with a history of smoking, more severe RA and steroid usage. The co-existence of RA and Br is associated with a poor 5 yr survival.

Adult↗
PubMed1997

Improved running performance in hot humid conditions following whole body precooling.

On two separate occasions, eight subjects controlled speed to run the greatest distance possible in 30 min in a hot, humid environment (ambient temperature 32 degrees C, relative humidity 60%). For the experimental test (precooling), exercise was preceeded by cold-water immersion. Precooling increased the distance run by 304 +/- 166 m (P < 0.05). Precooling decreased the pre-exercise rectal and mean skin temperature by 0.7 degrees C and 5.9 degrees C, respectively (P < 0.05). Rectal and mean skin temperature were decreased up to 20 and 25 min during exercise, respectively (P < 0.05). Mean body temperature decreased from 36.5 +/- 0.1 degrees C to 33.8 +/- 0.2 degrees C following precooling (P < 0.05) and remained lower throughout exercise (P < 0.01) and at the end of exercise (by 0.8 degrees C; P < 0.05). The rate of heat storage at the end of exercise increased from 113 +/- 45 to 249 +/- 55 W.m-2 (P < 0.005). Precooling lowered the heart rate at rest (13%), 5 (9%), and 10 min (10%) exercise (P < 0.05) and increased the end of exercise blood lactate from 4.9 +/- 0.5 to 7.4 +/- 0.9 mmol.L-1 (P < 0.01). The VO2 at 10 and 20 min of exercise and total body sweating are not different between tests. In conclusion, water immersion precooling increased exercise endurance in hot, humid conditions with an enhanced rate of heat storage and decreased thermoregulatory strain.

Adult↗
PubMed1997

Saturday night blue--a case of near fatal poisoning from the abuse of amyl nitrite.

A case of severe methaemoglobinaemia caused by the abuse of volatile nitrites is reported. The agents are commonly abused, but this complication is rare. The clinical presentation can make diagnosis difficult; however, the subsequent treatment needs to be rapid to avoid serious morbidity or mortality. This report presents the clinical picture and the background information leading to the detection and treatment of this unusual problem.

Adult↗
PubMed1997

Impaired calcium pump function does not slow relaxation in human skeletal muscle after prolonged exercise.

This study examined the effects of prolonged exercise on human quadriceps muscle contractile function and homogenate sarcoplasmic reticulum Ca2+ uptake and Ca2+-adenosinetriphosphatase activity. Ten untrained men cycled at 75 +/- 2% (SE) peak oxygen consumption until exhaustion. Biopsies were taken from the right vastus lateralis muscle at rest, exhaustion, and 20 and 60 min postexercise. Peak tension and half relaxation time of the left quadriceps muscle were measured during electrically evoked twitch and tetanic contractions and a maximal voluntary isometric contraction at rest, exhaustion, and 10, 20, and 60 min postexercise. At exhaustion, homogenate Ca2+ uptake and Ca2+ adenosinetriphosphatase activity were reduced by 17 +/- 4 and 21 +/- 5%, respectively, and remained depressed after 60 min recovery (P </= 0.01). Muscle ATP, creatine phosphate, and glycogen were all depressed at exhaustion (P </= 0.01). Peak tension during a maximal voluntary contraction, a twitch, and a 10-Hz stimulation were reduced after exercise by 28 +/- 3, 45 +/- 6, 65 +/- 5%, respectively (P </= 0.01), but no slowing of half relaxation times were found. Thus fatigue induced by prolonged exercise reduced muscle Ca2+ uptake, but this did not cause a slower relaxation of evoked contractions.

Adult↗
PubMed1996

Molecular epidemiology and significance of a cluster of cases of CMV infection occurring on a special care baby unit.

Sequencing of the amino-terminal region of the glycoprotein H gene was used to investigate the possibility of a common source for cytomegalovirus (CMV) infection occurring in five premature babies. All but two of the strains were different, indicating that this cluster of infection occurring on the special care baby unit was unlikely to be epidemiologically linked.

Cross Infection↗
PubMed1996

Effect of water ingestion on endurance capacity during prolonged running.

This study examined the influence of water ingestion on endurance capacity during submaximal treadmill running. Four men and four women with a mean (+/-S.E.) age of 21.4 +/- 0.7 years, height of 169 +/- 2 cm, body mass of 63.1 +/- 2.9 kg and VO2 max of 51.1 +/- 1.8 ml kg-1 min-1, performed two randomly assigned treadmill runs at 70% VO2 max to exhaustion. No fluid was ingested during one trial (NF-trial), whereas a single water bolus of 3.0 ml kg-1 body mass was ingested immediately pre-exercise and serial feedings of 2.0 ml kg-1 body mass were ingested every 15 min during exercise in a fluid replacement trial (FR-trial). Run time for the NF-trial was 77.7 +/- 7.7 min, compared to 103 +/- 12.4 min for the FR-trial (P < 0.01). Body mass (corrected for water ingestion) decreased by 2.0 +/- 0.2% in the NF-trial and 2.7 +/- 0.2% in the FR-trial (P < 0.01), while plasma volume decreased by 1.1 +/- 1.1% and 3.5 +/- 1.1% in the two trials respectively (N.S.). However, these apparent differences in circulatory volume were not associated with differences in rectal temperature. Respiratory exchange ratios indicated increased carbohydrate metabolism (73% vs 64% of total energy expenditure) and suppressed fat metabolism after 75 min of exercise in the NF-trial compared with the FR-trial (NF-trial, 0.90 +/- 0.01; FR-trial, 0.86 +/- 0.03; P < 0.01). Blood glucose concentrations were similar in both trials, while blood lactate concentrations were higher in the NF-trial at the end of exercise (4.83 +/- 0.34 vs 4.18 +/- 0.38 mM; P < 0.05). In summary, water ingestion during prolonged running improved endurance capacity.

Adult↗
PubMed1996

Enteroviral pharyngitis diagnosed by reverse transcriptase-polymerase chain reaction.

The role of enteroviruses in childhood pharyngitis was investigated using enteroviral specific reverse transcriptase-polymerase chain reaction (RT-PCR). Viral/bacterial throat swabs were taken from 50 children with acute pharyngitis and 26 controls. A positive culture was identified in only 26% of children with pharyngitis (adenovirus 10%, group A streptococci 2%), and none of the controls. Enteroviral RT-PCR was positive in 8% of the pharyngitis group and none of the controls. Enteroviruses are an important cause of pharyngitis in childhood.

Acute Disease↗
PubMed1996

Pathophysiology and treatment of hepatitis C.

Hepatitis C virus (HCV) infection is associated with a variable disease course and response to therapy. Some infected patients may develop little or no disease for 30 to 40 years, whereas others will develop cirrhosis within 5 to 10 years. Both host and viral factors influence the rate of disease progression. The management of patients is determined by the severity of their disease assessed by liver biopsy. Those with mild hepatitis without fibrosis do not require treatment but should undergo liver biopsy every 3 years. Patients with mild hepatitis with fibrosis, or with moderate or severe hepatitis with or without fibrosis, should be offered treatment. Interferon-alpha (IFN alpha) is currently the only licensed treatment for HCV infection. Although initial response rates to IFN alpha are high, over half the patients relapse and a sustained response is achieved in only 10 to 35% of patients. Higher doses of IFN alpha and a longer treatment duration are associated with better response rates. Treatment options for those who fail to respond to IFN alpha include a second course of IFN alpha at a higher dose or IFN alpha in combination with ribavirin, phlebotomy or ursodeoxycholic acid. At present, however, there are insufficient data to routinely recommend any of these options.

Hepatitis C↗
PubMed1995

Measurement of sarcoplasmic reticulum function in mammalian skeletal muscle: technical aspects.

Two recently developed methods for measuring the maximal rate of Ca2+ uptake and Ca2+ ATPase activity (EC 3.1.6.38) in vitro use muscle homogenate rather than isolated sarcoplasmic reticulum (SR). In this study we investigated technical aspects of these assays, including specificity and variability of the assays, the effect of different freezing treatments on maximal Ca2+ uptake and Ca2+ ATPase activity of human and rat muscle homogenate, stability of the homogenate, and the modification of the Ca2+ uptake assay to measure Ag(+)-induced Ca2+ release. Addition of cyclopiazonic acid (20 microM) blocked Ca2+ uptake, demonstrating specificity of the assay. Using frozen muscle homogenate, the inter- and intraassay variation for both assays was less than 9%. Whereas homogenates were stable to freezing for both Ca2+ uptake and Ca2+ ATPase activity, there was a significant (P < 0.05) decrease in activity when muscle was freeze-dried or quickly frozen in small pieces. After 1 h on ice, rat muscle homogenate Ca2+ uptake and Ca2+ ATPase activity had decreased by 6.0% (ns) and 3.6% (P < 0.05), respectively; after 3 h, activity had decreased by 15.3 and 14.7%, respectively (P < 0.01). The Ca2+ uptake assay was modified to allow measurement of Ag(+)-induced Ca2+ release. Following homogenate addition, after the SR vesicles were loaded with Ca2+ and [Ca2+] had declined to a plateau, AgNO3 (141 microM) was added, initiating release of Ca2+ into the assay solution. Addition of dithiothreitol (4 mM) blocked the Ag(+)-induced Ca2+ release, demonstrating specificity of the assay.

Animals↗
PubMed1995

The multifaceted role of the nurse in the day hospital.

This paper presents the initial findings from an action research study designed to explore and improve rehabilitation practice in a geriatric day hospital, The role of nurses in day hospitals and their contribution to rehabilitation form the focus of the discussion, which emanates from the analysis of semi-structured interviews with 13 members of the multi-disciplinary team, and observation of team meetings and patient reviews. Factors which influence the therapeutic activity of nurses are identified and tentative interpretations offered. The findings indicate that the nurse's role in day hospitals is multifaceted and varied and the conclusion is drawn that, far from being marginalized in rehabilitative and therapeutic terms, the nurse's central coordinating role should be recognized as the lynchpin of day hospital activity.

Attitude of Health Personnel↗
PubMed1995

Recurrent subarachnoid hemorrhage due to endometriosis.

A woman with a long history of menstruation-related headaches, at times associated with papilledema and brief episodes of unresponsiveness, was experiencing recurrent cryptogenic subarachnoid hemorrhage. Although the source of hemorrhage was never identified with certainty, strong circumstantial evidence suggested the presence of ectopic endometrial tissue in the spinal canal. Suppression of estrogen levels has prevented further episodes of hemorrhage.

Adult↗
PubMed1995

Preliminary predictions of athletic performance among collegiate baseball players with a biopsychosocial model.

This study investigated the association of nine biopsychosocial variables and athletic performance among 40 elite collegiate baseball players. High scores on confidence and perceived fitness and low scores on repressive denial, strength of religious faith, and sensitivity to glare were reliably associated with ratings of superior athletic performance by four coaches. Preliminary results suggest that the biopsychosocial model may prove useful in predicting athletic performance.

Adolescent↗
PubMed1994

Association of cytomegalovirus infection with post-transplantation cardiac rejection as studied using the polymerase chain reaction.

The relationship between cytomegalovirus (CMV) infection and cardiac allograft rejection is controversial, some authors reporting a significant association, others not, on the basis of the results of conventional virological diagnosis by culture or serology. This problem was reinvestigated in 88 patients using a semi-quantitative nest polymerase chain reaction (PCR) procedure for detecting CMV DNA in endomyocardial biopsy specimens. Significantly more positive biopsies were obtained from patients with moderate (grade 2; P = 0.02) or severe (grade 3a-4; P = 0.03) rejection than with no or mild (grade 0-1b) rejection, whereas there was no significant association between rejection and CMV as diagnosed by virus isolation from urine, throat or blood, or by the detection of CMV-IgM. PCR-positive biopsies originated most frequently from CMV-antibody positive recipients (R+) of hearts from seropositive donors (D+), in association with moderate or severe rejection rather than with mild or no rejection The detection of CMV in the heart thus seemed to be related more to R+D+ serological status than to severity of rejection, that is, to circumstances that favoured co-infection with strains of CMV from both donor and recipient. Studies on sequential biopsy specimens from selected patients also provided evidence that CMV infection and rejection were not always related events. The PCR was able to differentiate latent from active CMV infection; moreover, some seronegative individuals gave repeatedly positive biopsies, thereby supporting the work of others that some patients undergo CMV infection without mounting a detectable antibody response.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Fasciclin I and II have distinct roles in the development of grasshopper pioneer neurons.

We have used a new technique, micro-CALI (chromophore-assisted laser inactivation), to investigate the function of the neural cell adhesion molecules fasciclin I and II in the development of the grasshopper Ti1 neurons. Micro-CALI of fasciclin I results in defasciculation of the Ti1 axons similar to that achieved using large scale CALI (Jay and Keshishian, 1990). The initial point of axon separation corresponds to the site of laser irradiation, and defasciculation always continues distal to this point. Micro-CALI of fasciclin II prevents the initiation of Ti1 axon outgrowth but has no effect on fasciculation. This effect is restricted to a 3 hr interval between cytokinesis and growth cone emergence.

Animals↗