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Biomedical subjects

B Walsh

Publications and source records attributed to B Walsh.

At least 37 records · Page 2Linked to original sources
PubMed2001

Control of infection in acupuncture.

This paper is an update on infections, and potential infections, related to acupuncture, and a brief review of the relevant infection control procedures. There is no evidence at present to suggest that significant numbers of infections are being transmitted through standard acupuncture treatments in the UK. None the less, good infection control is essential. Like any other science, new research forces infection control to evolve and refine its procedures. Acupuncturists need to constantly review their standards as new viruses and risks are identified.

Acupuncture Therapy↗
PubMed2001

Guidelines for the control of hepatitis A virus infection.

The PHLS Advisory Committee on Vaccination and Immunisation, following a review of the evidence on control measures for preventing hepatitis A virus (HAV) infection and widespread consultation, has prepared the following guidelines. They include a description of the current epidemiology of HAV infection in England and Wales, where most individuals are now susceptible to HAV. HAV infection is uncommon, with around 1000 infections notified per year in England and Wales. Clusters occur in families and in settings where potential for faecal/oral spread is high, e.g. day care centres, nurseries, primary schools. Larger outbreaks have been recorded in men who have sex with men and injecting drug users. Personal hygiene remains the cornerstone of measures for preventing HAV infection and its spread. Those with haemophilia, hepatitis B or C virus infection or liver cirrhosis, intravenous drug users and men who have sex with men should be offered HAV vaccination as a preventive measure. HAV vaccine should be used for preventing secondary cases and outbreaks provided that patients are informed that the latest date the vaccine is most likely to be effective in preventing disease in contacts is probably 7 days from onset of illness in the primary case. Human normal immunoglobulin (HNIG) should be offered in addition or in preference to vaccine for contacts who are more than 7 days from onset of illness in the primary case, and for those at risk of adverse outcome of HAV infection. Individuals at particular risk of an adverse outcome to infection include those more than 50 years old, with liver cirrhosis of any cause, or with pre-existing hepatitis B or C virus infection. HAV vaccine should be used to prevent infection for travellers to countries where HAV infection is a risk. HNIG is no longer indicated for travellers. Children travelling to such countries should be offered vaccine from 5 years and consideration should be given to vaccinating those aged 1-4 years.

Adult↗
PubMed2000

Endurance training increases stimulation of uncoupling of skeletal muscle mitochondria in humans by non-esterified fatty acids: an uncoupling-protein-mediated effect?

Uncoupled respiration (UCR) is an essential property of muscle mitochondria and has several functions in the cell. We hypothesized that endurance training may alter the magnitude and properties of UCR in human muscle. Isolated mitochondria from muscle biopsies taken before and after 6 weeks of endurance exercise training (n=8) were analysed for UCR. To investigate the role of uncoupling protein 2 (UCP2) and UCP3 in UCR, the sensitivity of UCR to UCP-regulating ligands (non-esterified fatty acids and purine nucleotides) and UCP2 and UCP3 mRNA expression in muscle were examined. Oleate increased the mitochondrial oxygen consumption rate, an effect that was not attenuated by GDP and/or cyclosporin A. The effect of oleate was significantly greater after compared with before training. Training had no effect on UCP2 or UCP3 mRNA levels, but after training the relative increase in respiration rate induced by oleate was positively correlated with the UCP2 mRNA level. In conclusion, we show that the sensitivity of UCR to non-esterified fatty acids is up-regulated by endurance training. This suggests that endurance training causes intrinsic changes in mitochondrial function, which may enhance the potential for regulation of aerobic energy production, prevent excess free radical generation and contribute to a higher basal metabolic rate.

Adult↗
PubMed2000

Mitochondrial function and antioxidative defence in human muscle: effects of endurance training and oxidative stress.

The influence of endurance training on oxidative phosphorylation and the susceptibility of mitochondrial oxidative function to reactive oxygen species (ROS) was investigated in skeletal muscle of four men and four women. Mitochondria were isolated from muscle biopsies taken before and after 6 weeks of endurance training. Mitochondrial respiration was measured before and after exposure of mitochondria to exogenous ROS (H2O2 + FeCl2). Endurance training increased peak pulmonary O2 uptake (VO2,peak) by 24 % and maximal ADP-stimulated mitochondrial oxygen consumption (state 3) by 40% (P<0.05). Respiration in the absence of ADP (state 4), the respiratory control ratio (RCR = state 3/state 4) and the ratio between added ADP and consumed oxygen (P/O) remained unchanged by the training programme. Exposure to ROS reduced state 3 respiration but the effect was not significantly different between pre- and post-training samples. State 4 oxygen consumption increased after exposure to ROS both before (+189 %, P< 0.05) and after training (+243 %, P<0.05) and the effect was significantly higher after training (P<0.05, pre- vs. post-training). The augmented state 4 respiration could in part be attenuated by atractyloside, which indicates that ADP/ATP translocase was affected by ROS. The P/O ratio in ROS-treated mitochondria was significantly lower (P<0.05) compared to control conditions, both before (-18.6+/-2.2 %) and after training (-18.5+/-1.1%). Muscle activities of superoxide dismutase (mitochondrial and cytosolic), glutathione peroxidase and muscle glutathione status were unaffected by training. There was a positive correlation between muscle superoxide dismutase activity and age (r = 0.75; P<0.05; range of age 20-37 years), which may reflect an adaptation to increased generation of ROS in senescent muscle. The muscle glutathione pool was more reduced in subjects with high activity of glutathione peroxidase (r = 0.81; P<0.05). The influence of short-term training on mitochondrial oxygen consumption has for the first time been investigated in human skeletal muscle. The results showed that maximal mitochondrial oxidative power is increased after endurance training but that the efficiency of energy transfer (P/O ratio) remained unchanged. Antioxidative defence was unchanged after training when expressed relative to muscle weight. Although this corresponds to a reduced antioxidant protection per individual mitochondrion, the sensitivity of aerobic energy transfer to ROS was unchanged. However, the augmented ROS-induced non-coupled respiration after training indicates an increased susceptibility of mitochondrial membrane proton conductance to oxidative stress.

Adult↗
PubMed2000

Low molecular weight analysis of tears using matrix assisted laser desorption ionization-time of flight mass spectrometry.

Many low molecular weight substances in human tears, including protein and lipid species, have yet to be characterized. Some of these uncharacterized substances may well be important in the pathogenesis of ocular surface disease or in ocular discomfort. The aim of this study was to build a biochemical profile of low molecular weight species in tears, and to determine its repeatability. A total of 80 tear samples were collected from 11 subjects. Tear samples were dialysed to remove salts, added to a matrix of alpha-cyano-4-hydroxycinnamic acid, and analysed using matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry. Species were separated based on their mass to charge ratio (m:z). The repeatability of the appearance of the different species was analysed using logistic regression and diurnal and day-to-day repeatability were ascertained. Peptides were identified in the range of 848 3897 Da. Of these, 39 peptides were found to be present in more than 10/80 samples. There was no diurnal variation in the peptides. All species were found to occur repeatably, with the exception of peptide 1653 Da.This study has demonstrated that the majority of low molecular weight species in tears are repeatably present and do not exhibit diurnal variation. Further study aims to characterize these species and to identify changes in tear profiles between subject groups.

Adult↗
PubMed2000

Hospital outbreak of Salmonella virchow possibly associated with a food handler.

A foodborne outbreak of salmonella infection at a private hospital in London in 1994 was found to be associated with eating turkey sandwiches prepared by a food handler. One patient, nine staff, and a foodhandler's baby were confirmed to have Salmonella enterica serotype virchow, phage type 26 infection. The attack rate was estimated to be 5% among the approximately 200 patients and staff at risk. A food handler reportedly became ill days after, but her baby days before, the first hospital case. Although it appeared to be a single outbreak, antibiogram analysis, supplemented by plasmid profile typing, demonstrated that there were two strains of S. virchow involved, one with resistance to sulphonamides and trimethoprim and a second sensitive to these antimicrobial drugs. Mother and child had different strains. The investigation demonstrated the importance of full phenotypic characterization of putative outbreak strains including antimicrobial susceptibility testing. Outbreaks of foodborne infection in hospitals are preventable and are associated with high attack rates and disruption of services. There is a need for good infection control policies and training of all staff involved in patient care as well as in catering services. Consultants in Communicable Disease (CCDCs) should include private hospitals in their outbreak control plans. Good working relations between Infection Control Doctors (ICDs) in the private health sector and their local CCDCs are important if outbreaks are to be properly investigated.

Adult↗
PubMed1999

Mitochondrial function in human skeletal muscle is not impaired by high intensity exercise.

The hypothesis that high-intensity (HI) intermittent exercise impairs mitochondrial function was investigated with different microtechniques in human muscle samples. Ten male students performed three bouts of cycling at 130% of peak O2 consumption (V.O2,peak). Muscle biopsies were taken from the vastus lateralis muscle at rest, at fatigue and after 110 min recovery. Mitochondrial function was measured both in isolated mitochondria and in muscle fibre bundles made permeable with saponin (skinned fibres). In isolated mitochondria there was no change in maximal respiration, rate of adenosine 5'-triphosphate (ATP) production (measured with bioluminescence) and respiratory control index after exercise or after recovery. The ATP production per consumed oxygen (P/O ratio) also remained unchanged at fatigue but decreased by 4% (P<0.05) after recovery. In skinned fibres, maximal adenosine 5'-diphosphate (ADP)-stimulated respiration increased by 23% from rest to exhaustion (P<0.05) and remained elevated after recovery, whereas the respiratory rates in the absence of ADP and at 0.1 mM ADP (submaximal respiration) were unchanged. The ratio between respiration at 0.1 and 1 mM ADP (ADP sensitivity index) decreased at fatigue (P<0.05) but after the recovery period was not significantly different from that at rest. It is concluded that mitochondrial oxidative potential is maintained or improved during exhaustive HI exercise. The finding that the sensitivity of mitochondrial respiration to ADP is reversibly decreased after strenuous exercise may indicate that the control of mitochondrial respiration is altered.

Adenosine Diphosphate↗
PubMed1999

Outbreak of hepatitis B in an acupuncture clinic.

A retrospective cohort serological study identified five confirmed cases of acute hepatitis B virus (HBV) infection in three and a half years at an acupuncture clinic in London. These cases made up 1.7% of those treated by an acupuncturist who was a hepatitis B 'e' antigen (HBeAg) carrier. Virus subtyping and polymerase chain reaction--single strand conformation polymorphism assay (PCR-SSCPA) showed that strains of virus from the acupuncturist and two of the five patients for whom it was possible to perform the test were indistinguishable. Nine other patients who attended the same acupuncturist had antibody to the hepatitis B core antigen but had other risk factors for HBV infection. No obvious mode of transmission was identified but cross contamination of needles could not be ruled out in two cases. The fifth case was exposed to HBV after disposable needles were introduced. Routine immunisation of acupuncturists against HBV is recommended.

Acupuncture Therapy↗
PubMed1998

Evidence for the continuity of early problem behaviors: application of a developmental model.

Evidence of the continuity of early problem behaviors in young girls and boys was examined developmentally. Data were gathered on 104 mother-child dyads from low-income families when children were between 1 and 5 years of age. Difficult temperament, aggression, and noncompliance from 12 to 24 months, and externalizing and internalizing problems at 36 and 60 months, were assessed. The results provide evidence for the continuity of early behavioral and emotional problems and support for the early differentiation between internalizing and externalizing problems. Implications of the current findings for prevention efforts are presented.

Aggression↗
PubMed1998

Long-term in vivo cochlear transgene expression mediated by recombinant adeno-associated virus.

Adeno-associated virus (AAV) integrated transgene expression within guinea pig cochlea has been previously documented. This article extends these studies by characterizing the AAV-mediated gene transfer for duration of transgene expression within the cochlea and its effect upon cochlear cytoarchitecture over a period of 6 months. All animals infused with AAV expressed the transgene product, bacterial beta-galactosidase (beta-gal) enzyme, in the spiral limbus, spiral ligament, spiral ganglion cells and the organ of Corti at 2-24 weeks after infusion. However, the level of beta-gal expression, as determined from intensity of immunoreactivity, was relatively lower at 24 weeks as compared with 2 weeks. The cellular and tissue architecture within the AAV-beta-gal perfused cochleae, harvested 2-8 weeks after AAV infusion, was generally intact, ie free from inflammation and cellular degeneration. However, cellular degeneration and degradation was apparent in the cochleae of some but not all animals harvested at 12 and 24 weeks after AAV infusion.

Animals↗
PubMed1998

Effects of estrogen replacement therapy on the lipoprotein profile in postmenopausal women with ESRD.

BACKGROUND: Patients with ESRD have excessive cardiovascular morbidity and mortality. In postmenopausal women with normal renal function, estrogen replacement therapy decreases cardiovascular mortality by 50%, in part because of their beneficial effects on the lipoprotein profile. Because of similarities in the lipoprotein profile between healthy, postmenopausal women, and women with ESRD, we examined the effects of estrogen replacement on lipoproteins in 11 postmenopausal women with ESRD. METHODS: In a randomized, placebo-controlled crossover study (8 week treatment arms) using 2 mg daily of oral, micronized estradiol, 11 postmenopausal women with ESRD were treated. Neither baseline lipid nor lipoprotein abnormalities were used as entry criteria for study participation. RESULTS: Blood estradiol levels were 19 +/- 4 with placebo and 194 +/- 67 pg/ml (P = 0.024) with estradiol treatment. Total HDL cholesterol concentrations increased from 52 +/- 19 mg/dl to 61 +/- 20 mg/dl (16%), with placebo and estradiol treatments, respectively (P = 0.002). Apolipoprotein A1 increased by 24.6% (P = 0.0002) with estradiol intervention. HDL2 concentrations were 19 +/- 13 with placebo and 24 +/- 16 with estradiol treatment (P = 0.046). There were no differences in total or LDL cholesterol, other lipoprotein fractions including Lp(a), and triglycerides with 2 mg daily estradiol treatment. No significant side effects were observed. CONCLUSIONS: Therefore, using standard dosage regimens for estrogen replacement therapy in postmenopausal women with ESRD, HDL cholesterol is increased to an extent that would be expected to improve their cardiovascular risk profile. Further studies are needed to assess whether estrogen replacement therapy decreases the incidence or severity of cardiovascular disease in ESRD patients to a similar degree compared with other women.

Cardiovascular Diseases↗
PubMed1998

Arthritis and HLA-B27 in native North American tribes.

Whereas it is clear that HLA-B27 is increased in many North American natives, the prevalence varies a great deal. There is still a paucity of data on a large number of tribes. There is, however, a suggestion that HLA-B27 positive prevalence follows cultural/linguistic groupings. Reactive arthritis, sacroiliitis, and ankylosing spondylitis also appear to be increased in these people, but their relationship to HLA-B27 and possibly additional genetic predisposing factors is far from clear. Given these data and the known association of infectious agents, more extensive studies are warranted, especially in those tribes with a large enough population to achieve statistical significance.

Arthritis↗
PubMed1998

Effects of different hormone replacement regimens on postmenopausal women with abnormal lipid levels. Menopause Study Group.

OBJECTIVES: A retrospective, subset analysis of the prospective Menopause Study Group data was performed to determine the effects of four conjugated estrogens (CE) + medroxyprogesterone acetate (MPA) regimens and one unopposed CE regimen on the lipid profiles of women with abnormal lipid levels (n = 525). Previously unpublished data on the entire study population were also reviewed to determine the effects of these hormone replacement regimens on blood pressure and weight (n = 1368, 1374, respectively). METHODS: During a 1-year, prospective trial, all patients took CE. Groups A and B also took continuous MPA 2.5 and 5 mg, respectively, C and D took MPA 5 and 10 mg for the last 14 cycle days of each 28-day cycle, and E took matching placebo tablets to replace MPA. RESULTS: After 1 year, all five regimens were directly associated with significant elevations in high density lipoprotein-2 (HDL2) cholesterol and significant reductions in low density lipoprotein (LDL) cholesterol (p < 0.05), although unopposed estrogen produced the greatest increase in HDL2 cholesterol. The CE + MPA regimens were also associated with significant decreases in total cholesterol. Triglyceride levels did not change significantly from baseline in any treatment group (baseline values > 1.808 mmol/l (> 160 mg/dl)), although the CE + MPA regimens were associated with a mean triglyceride decrease and CE-only women (n = 8) had a mean triglyceride increase. No regimen produced significant weight or blood pressure changes. CONCLUSIONS: This analysis suggests that hormone replacement therapy (CE + MPA), used in appropriate dosages, may alter the HDL2 cholesterol and LDL cholesterol lipoproteins in postmenopausal women with borderline lipid levels (a higher-risk population) in a cardioprotective manner.

Blood Pressure↗
PubMed1997

DSM-III-R disorders in preschool children from low-income families.

OBJECTIVE: To generate rates of DSM-III-R disorders in a sample of preschool children from low-income families, examine impairment ratings for preschool children meeting criteria for DSM-III-R disorders, and compare rates of psychopathology using DSM-III-R criteria with rates generated by the Child Behavior Checklist (CBCL). METHOD: As part of an ongoing longitudinal study of 104 mother-child dyads from low-income families, data were gathered when children were 5 years of age. DSM-III-R disorders were diagnosed through the administration of the Schedule for Affective Disorders and Schizophrenia for School-Age Children to the mothers, and mothers competed the CBCL. RESULTS: Rates of DSM-III-R disorders among preschool children from low-income families were higher than those reported in community samples, but comparable with rates for low-income school-age children and adolescents. Children meeting criteria for DSM-III-R disorders were rated as significantly impaired. The prevalence of behavioral and emotional problems was similar by both DSM-III-R criteria and the CBCL. There was some evidence, however, that the two systems identified different children. CONCLUSIONS: DSM-III-R criteria appear to adequately identify preschool children with serious behavioral and emotional problems. Longitudinal studies are needed to explore further the relative utility of the DSM and CBCL in the identification of psychopathology in preschool children.

Chi-Square Distribution↗
PubMed1997

Classification of mild Alzheimer's disease by artificial neural network analysis of SPET data.

An evaluation of the performance of artificial neural networks (ANNs) for the classification of probable Alzheimer's disease (pAD) patients was undertaken using data extracted from four regions of interest constructed on single photon emission tomographic (SPET) cerebral perfusion images. Two studies using feed-forward neural networks (FFNNs) were undertaken. The first was to determine if it would be possible to classify pAD patients and normal subjects in a mixed group, comprising 29 patients diagnosed as having pAD varying in severity from mild, established dementia to moderate dementia and 10 healthy control subjects. The second was to determine if the networks generated in the first study could prospectively classify 15 additional patients with very mild or mild cognitive impairment. The results were compared to those obtained using the same data and discriminant analysis. The relative performances of the two analysis techniques were assessed on the basis of the area under receiver operating characteristics (ROC) curves. The FFNN successfully classified all datasets in the first study, achieving an area under the ROC curve of 1.00, whereas discriminant analysis achieved 0.94. When tested on data from the second group, the areas under the ROC curves varied between 0.86 and 1.00 for the FFNN, whereas that for discriminant analysis was 0.99. We conclude that FFNNs can accurately classify pAD patients with mild to moderate dementia using data obtained from SPET cerebral perfusion images.

Aged↗
PubMed1997

Trends in alcohol production, trade and consumption.

This paper is a survey of the structure and significance of international trade in alcoholic beverages in the contemporary world economy. It presents data on the level of trade in the main alcoholic beverages for the period since 1970. The constant-dollar value of this trade grew by a factor of 2.1 between 1975 and 1992. It represents approximately one half of the one per cent of the value of world trade in all commodities. This proportion has remained very stable over the past 20 years. International trade in beer, wine and spirits has greatly extended the range of alcoholic beverages available around the world and reduced their cost. It has played a large part in the tendency for convergence in the patterns of alcohol consumption, as countries diversify away from their dependence on locally produced beverages. Traditional spirits-drinking and beer-drinking countries have witnessed very rapid increases in the consumption of wine, while heavy wine drinking countries have seen rapid growth of the consumption of beer. While imported beverages remain relatively unimportant in total consumption of alcoholic beverages, they have played a significant role in the growth and diversification of alcohol consumption in many countries.

Alcohol Drinking↗