626
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Abstract
Background—
Systemic lupus erythematosus (SLE) patients have a significantly increased risk of coronary heart disease (CHD) that is not fully explained by classic risk factors. Endothelial dysfunction is an early stage in the process of atherogenesis. Our aim was to determine whether endothelial dysfunction occurs in SLE and whether it is associated with the occurrence of classic Framingham risk factors.
Methods and Results—
We studied 62 women with SLE (1997 revised criteria) and 38 healthy women. Demographic and risk factor data were collected. In patients, disease activity and treatment-related parameters were also assessed. Endothelial function was assessed by flow-mediated dilation (FMD) in the brachial artery in response to reactive hyperemia. Carotid intima-media thickness (IMT) and the presence of carotid plaques were also assessed in SLE patients. FMD was impaired in SLE patients (median, 3.6%; range, −6.3% to 13.7%; versus median, 6.9%; range, −6.6% to 17.8%,
P
<0.01). Using multiple regression analysis that included all subjects in which we retained all the classic CHD risk factors, we found that systolic blood pressure (
P
=0.019) and SLE (
P
=0.017) were significantly associated with impaired FMD. Within SLE patients, IMT showed a negative correlation with percent FMD (
r
=−0.37,
P
<0.01). In stepwise multiple regression of SLE patients only that also included SLE factors and IMT, IMT alone was independently associated with FMD (
P
=0.037).
Conclusions—
Patients with SLE have endothelial dysfunction that remained significant even after adjustment for other classic CHD risk factors. Within SLE patients, endothelial dysfunction correlates negatively with IMT, another marker of early atherosclerosis. Understanding the mechanism(s) of endothelial dysfunction in SLE may suggest novel strategies for CHD prevention in this context.
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627
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McIntyre EA, Halse R, Yeaman SJ, Walker M. Cultured muscle cells from insulin-resistant type 2 diabetes patients have impaired insulin, but normal 5-amino-4-imidazolecarboxamide riboside-stimulated, glucose uptake. J Clin Endocrinol Metab 2004; 89:3440-8. [PMID: 15240629 DOI: 10.1210/jc.2003-031919] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Impaired insulin action is a characteristic feature of type 2 diabetes. The study aims were to investigate whether after prolonged culture skeletal muscle cultures from insulin-resistant, type 2 diabetic patients (taking >100 U insulin/d) displayed impaired insulin signaling effects compared with cultures from nondiabetic controls and to determine whether retained abnormalities were limited to insulin action by studying an alternative pathway of stimulated glucose uptake. Studies were performed on myotubes differentiated for 7 d between passages 4 and 6. Insulin-stimulated glucose uptake (100 nm; P < 0.05) and insulin-stimulated glycogen synthesis (1 nm; P < 0.01) were significantly impaired in the diabetic vs. control cultures. Protein kinase B (PKB) expression and phosphorylated PKB levels in response to insulin stimulation (20 nm) were comparable in the diabetic and control cultures. 5-Amino-4-imidazolecarboxamide riboside (AICAR) mimics the effect of exercise on glucose uptake by activating AMP-activated protein kinase. There was no difference in AICAR (2 mm)-stimulated glucose uptake between diabetic vs. control myotube cultures (P = not significant). In conclusion, diabetic muscle cultures retain signaling defects after prolonged culture that appear specific to the insulin signaling pathway, but not involving PKB. This supports an intrinsic abnormality of the diabetic muscle cells that is most likely to have a genetic basis.
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628
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Jones SA, Bowler PG, Walker M, Parsons D. Controlling wound bioburden with a novel silver-containing HydrofiberR dressing. Wound Repair Regen 2004; 12:288-94. [PMID: 15225207 DOI: 10.1111/j.1067-1927.2004.012304.x] [Citation(s) in RCA: 206] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Clinicians now recognize that both aerobic and anaerobic microorganisms have the ability to degrade or damage host tissue at a wound site through the production of a variety of enzymes and toxins. Silver-containing dressings offer one method for controlling this polymicrobial wound bioburden, and research efforts are currently ongoing to determine their efficacy against aerobic, anaerobic, and antibiotic-resistant microorganisms. The current study aimed to determine the antimicrobial activity of a new silver-containing Hydrofiber dressing (AQUACEL Ag) on both aerobic and anaerobic microorganisms, using the zone-of-inhibition method. This method provides a measure of the ability of the dressing to make available a sufficient concentration of silver to have an antimicrobial effect. To some extent this test mimics the clinical use of the dressing and predicts its microbicidal activity at the wound-dressing interface. The results show that the silver-containing dressing makes silver available at a dressing-agar interface at a concentration that is effective against a broad range of aerobic, anaerobic, and antibiotic-resistant microorganisms. In the context of wound healing, the results showing antimicrobial activity against antibiotic-resistant microorganisms are particularly important, as the control and eradication of these organisms is a major concern within the health care profession.
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629
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Ghosh J, Murray D, Kielty C, Walker M. MODULATION OF HUMAN CORONARY ARTERY SMOOTH MUSCLE CELLS BY SHEAR STRESS: THE ROLE OF TGF BETA1. Cardiovasc Pathol 2004. [DOI: 10.1016/j.carpath.2004.03.572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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630
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Khwaja N, Ghosh J, Howarth V, Murray D, McMahon R, Brenchley P, Eddleston J, Walker M. COLONIC MUCOSA IS A SOURCE OF INTERLEUKIN-6 PRODUCTION FOLLOWING ISCHAEMIA-REPERFUSION INJURY. Cardiovasc Pathol 2004. [DOI: 10.1016/j.carpath.2004.03.046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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631
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Alkazaleh F, Viero S, Simchen M, Walker M, Smith G, Laskin C, Windrim R, Kingdom J. Ultrasound diagnosis of severe thrombotic placental damage in the second trimester: an observational study. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2004; 23:472-476. [PMID: 15133798 DOI: 10.1002/uog.1044] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
OBJECTIVES To screen women with uteroplacental insufficiency between 18 and 26 weeks' gestation for sonographic evidence of destructive placental lesions, to observe the effect of low molecular-weight heparin (LMWH) in these cases, and to compare the outcome with similar but untreated controls. METHODS We screened 180 women at high risk for placental damage using 16-week maternal serum screening (alpha-fetoprotein and human chorionic gonadotropin), placental shape and texture, and uterine artery Doppler waveforms at the 18-20-week level II examination. Serial gray-scale examinations of placental texture were performed at 22, 24 and 26 weeks. LMWH was offered to women with ultrasound evidence of destructive placental lesions in the absence of intrauterine growth restriction and/or pre-eclampsia. RESULTS We prospectively identified six women (3.3%) with abnormal maternal serum screening and uterine artery Doppler in whom abnormal placental texture (echogenic cystic lesions) suggestive of destructive lesions in the placental parenchyma was found either at the 18-20-week ultrasound examination (n = 4), or by 26 weeks of gestation (n = 2). All six received LMWH and had live births (gestational age at delivery, 33-37 weeks; birth weight, 1000-3200 g). A further 14 women were referred with similar multiparameter evidence of placental damage at or after 26 weeks, outside the screening study. All had significant fetal growth restriction and were therefore not offered heparin. In 9/14 cases there was a perinatal death. Ischemic and/or thrombotic placental pathology was confirmed in each case, but no maternal thrombophilia disorders were identified in the 20 women. CONCLUSIONS Integrated biochemical and ultrasound testing of placental function at 16-20 weeks of gestation, followed by serial placental gray-scale ultrasound, may be an effective method of identifying a subset of pregnancies at high risk of adverse pregnancy outcome due to destructive lesions in the placental parenchyma. This strategy of identifying thrombo-occlusive placental lesions before the development of pregnancy complications may prove useful in the design of trials to study the effectiveness of LMWH in the prevention of clinical complications resulting from thrombo-occlusive placental disease.
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632
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Owen KR, Evans JC, Frayling TM, Hattersley AT, McCarthy MI, Walker M, Hitman GA. Role of the D76N polymorphism of insulin promoter factor-1 in predisposing to Type 2 diabetes. Diabetologia 2004; 47:957-8. [PMID: 15170499 DOI: 10.1007/s00125-004-1397-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2004] [Accepted: 03/01/2004] [Indexed: 11/29/2022]
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633
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Bennett SMA, Agrawal A, Elasha H, Heise M, Jones NP, Walker M, Wilding JPH. Rosiglitazone improves insulin sensitivity, glucose tolerance and ambulatory blood pressure in subjects with impaired glucose tolerance. Diabet Med 2004; 21:415-22. [PMID: 15089784 DOI: 10.1111/j.1464-5491.2004.01155.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS To determine the effects of rosiglitazone on insulin sensitivity, glucose tolerance and ambulatory blood pressure when administered to subjects with persistent impaired glucose tolerance (IGT). METHODS Eighteen subjects with persistent IGT were randomized to receive rosiglitazone 4 mg twice daily or matching placebo for 12 weeks. Evaluation at baseline and at the end of treatment included measurement of whole body insulin sensitivity during a euglycaemic hyperinsulinaemic clamp and deriving an insulin sensitivity index. Changes in glucose and insulin concentration were determined after oral glucose tolerance test (OGTT) and mixed meal tolerance tests, and 24-h ambulatory blood pressure was monitored. RESULTS Rosiglitazone significantly improved the insulin sensitivity index by 2.26 micro g/kg per min per pmol/l relative to placebo (P = 0.0003). Four of nine subjects receiving rosiglitazone reverted to normal glucose tolerance and 5/9 remained IGT, although four of these had improved 2-h glucose values. In the placebo group, 1/9 subjects progressed to Type 2 diabetes and 8/9 remained IGT. Following OGTT and meal tolerance test, glucose and insulin area under curve were reduced over 3 and 4 h, respectively. Compared with placebo, ambulatory blood pressure decreased significantly in the rosiglitazone group by 10 mmHg systolic (P = 0.0066) and 8 mmHg diastolic (P = 0.0126). CONCLUSIONS Consistent with its effects in patients with Type 2 diabetes, rosiglitazone substantially improved whole body insulin sensitivity and the glycaemic and insulinaemic responses to an OGTT and meal tolerance test in subjects with persistent IGT. Furthermore, rosiglitazone reduced systolic and diastolic ambulatory blood pressure in these subjects.
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634
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Baguneid M, Murray D, Salacinski HJ, Fuller B, Hamilton G, Walker M, Seifalian AM. Shear-stress preconditioning and tissue-engineering-based paradigms for generating arterial substitutes. Biotechnol Appl Biochem 2004; 39:151-7. [PMID: 15032735 DOI: 10.1042/ba20030148] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In situ tissue engineering using shear-stress preconditioning and adhesive biomolecules is a new approach to autologous tissue engineering. In the present study, novel tissue-engineering grafts (TEGs) were preconditioned within an in vitro pulsatile flow circuit, with and without the addition of fibronectin (FN), to establish whether low-shear-stress conditions promoted endothelial cell (EC) retention and differentiation. TEGs ( n =24) were generated by the contraction and compaction of collagen(I) by porcine aortic smooth-muscle cells (SMCs) on to a compliant polyester graft scaffold. ECs were radiolabelled with [(111)In]indium tropolonate and seeded on to the luminal surface of the TEGs. Following organ culture in a bioreactor (7 days), TEGs were split into four groups ( n =six TEGs per group): Group A acted as controls with TEGs unmodified and seeded with radiolabelled ECs; Group B underwent luminal pre-coating with FN (75 microg/ml) prior to EC seeding; Group C underwent preconditioning within a pulsatile flow circuit at 10-20 microN (1-2 dyn)/cm(2) for 7 days prior to EC seeding, and Group D TEGs were preconditioned for 7 days at 1-2 dyn/cm(2), followed by luminal pre-coating with FN prior to EC seeding. The resistance to physiological shear stress of the seeded ECs was assessed using a gamma-radiation counter within a physiological flow circuit producing an arterial waveform with a mean shear stress of 93.2 microN (9.32 dyn)/cm(2). Environmental scanning electron microscopy (ESEM) was used to determine the distribution and degree of differentiation of the attached Ecs, and tissue-type-plasminogen-activator (tPA) assays provided a measure of function and viability. EC resistance to shear stress at 93.2 microN/cm(2) was significantly enhanced by a period of preconditioning (Group C) at 10-20 microN/cm(2), surface modification with FN (Group B), or both (Group D) when compared with control grafts (Group A). However, TEGs coated with FN whether preconditioned (Group D) or not (Group B) demonstrated the best results for EC retention. ESEM demonstrated near-confluent differentiated flattened ECs in both these cases. EC function was demonstrated by a steady increase in tPA production. Low-shear-stress preconditioning of TEGs enhances EC retention in vitro with an additional advantage demonstrated by pre-treatment with FN prior to endothelialization. These findings may be exploited in the development of tissue-engineered constructs to maintain a confluent endothelial lining.
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635
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Mills GW, Avery PJ, McCarthy MI, Hattersley AT, Levy JC, Hitman GA, Sampson M, Walker M. Heritability estimates for beta cell function and features of the insulin resistance syndrome in UK families with an increased susceptibility to type 2 diabetes. Diabetologia 2004; 47:732-8. [PMID: 15298351 DOI: 10.1007/s00125-004-1338-2] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
AIMS/HYPOTHESIS The aim of this study was to measure the heritability estimates for metabolic traits and the features of the insulin resistance syndrome in families with an increased genetic susceptibility to Type 2 diabetes. METHODS A total of 811 non-diabetic relatives from 278 pedigrees of northern European extraction in which there was a sib-pair with Type 2 diabetes were recruited and studied at the six Diabetes UK Warren Type 2 diabetes centres. Heritability estimates were calculated, allowing for key covariates (age, sex, BMI and recruitment centre). Values greater than 0.10 were considered statistically significant in comparison to zero. RESULTS Fasting glucose concentration and homeostasis model assessment of pancreatic beta cell function (HOMA %B) had the highest heritability estimates of 0.72 and 0.78 respectively. Heritability estimates for the features of the insulin resistance syndrome (BMI, WHR, systolic and diastolic blood pressure, serum lipids and homeostasis model assessment of insulin sensitivity [HOMA %S]) were also high. The heritability estimate for fasting glucose was markedly higher in the present study (0.77 vs 0.21 adjusted for age and sex; p<0.001) than in a comparable study of families from the same background population but with no increased susceptibility to diabetes. However, the estimates for the features of the insulin resistance syndrome were similar in the two studies. CONCLUSIONS/INTERPRETATION In families with a high risk of Type 2 diabetes, the heritability estimates for fasting glucose, pancreatic beta cell function and the features of the insulin resistance syndrome were all high. The higher heritability estimate for pancreatic beta cell function suggests that this resource may be most effective when investigating genetic susceptibility to beta cell dysfunction.
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636
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Wedekind C, Walker M, Portmann J, Cenni B, Müller R, Binz T. MHC-linked susceptibility to a bacterial infection, but no MHC-linked cryptic female choice in whitefish. J Evol Biol 2004; 17:11-8. [PMID: 15000643 DOI: 10.1046/j.1420-9101.2004.00669.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Non-random gamete fusion is one of several potential cryptic female choice mechanisms that have been postulated and that may enhance the survival probability of the offspring. Previous studies have found that gamete fusion in mice is influenced by genes of the major histocompatibility complex (MHC) region. Here we test (i) whether there is MHC-dependent gamete fusion in whitefish (Coregonus sp.) and (ii) whether there is a link between the MHC and embryo susceptibility to an infection by the bacterium Pseudomonas fuorescens. We experimentally bred whitefish and reared sibships in several batches that either experienced or did not experience strong selection by P. fluorescens. We then determined the MHC class II B1 genotype of 1016 surviving larvae of several full sibships. We found no evidence for MHC-linked gamete fusion. However, in one of seven sibships we found a strong connection between the MHC class II genotype and embryo susceptibility to P. fluorescens. This connection was still significant after correcting for multiple testing. Hence, the MHC class II genotype can considerably influence embryo survival in whitefish, but gamete fusion seems to be random with respect to the MHC.
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637
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Ladouceur R, Bouchard C, Rhéaume N, Jacques C, Ferland F, Leblond J, Walker M. Is the SOGS an accurate measure of pathological gambling among children, adolescents and adults? J Gambl Stud 2004; 16:1-24. [PMID: 14634319 DOI: 10.1023/a:1009443516329] [Citation(s) in RCA: 157] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The South Oaks Gambling Screen (SOGS) is widely used to assess the prevalence of pathological gambling. For a variety of reasons, this instrument may not provide an accurate rate of the prevalence of pathological gambling. In this paper, one source of error in data provided by the SOGS is investigated. It is argued that individuals may not fully understand the meaning of some items, and that clarification of the meaning of misunderstood items may in some cases lead to a changed score on the scale. The present study evaluates respondents' understanding of the SOGS items. The results from three studies are reported, each using a different sample: grade school children, adolescents and adults. It was hypothesised that (1) participants would not understand some items of the SOGS, (2) problem gamblers and probable pathological gamblers would be more inclined to interpret items incorrectly than would non-problem gamblers and, (3) consistent with the first two hypotheses, clarification of items would decrease the number of participants identified as problem gamblers or probable pathological gamblers. The data obtained supported hypotheses 1 and 3. Furthermore, hypothesis 2 was supported for grade school children, but not for adolescents or adults. These results are consistent with recent literature on endorsement and acquiescence phenomena, and have implications for prevalence studies of probable pathological gambling.
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638
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Bowler PG, Jones SA, Walker M, Parsons D. Microbicidal Properties of a Silver-Containing Hydrofiber?? Dressing Against a Variety of Burn Wound Pathogens. ACTA ACUST UNITED AC 2004; 25:192-6. [PMID: 15091147 DOI: 10.1097/01.bcr.0000112331.72232.1b] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Partial-thickness burns are often characterized by microbial contamination and copious exudate produced during the early postburn period. Consequently, topical wound management often relies on the use of antimicrobial agents and absorbent dressings, and an AQUACEL Hydrofiber Dressing containing ionic silver has been designed to meet such needs. To assess the antimicrobial properties of the AQUACEL Hydrofiber dressing, samples were challenged with a wide variety of recognized burn wound pathogens in a simulated wound fluid model. Dressing samples were inoculated with the challenge organisms at time zero and then reinoculated on days 4 and 9 to mimic the worst-case clinical scenario. The dressing was shown to be microbicidal against aerobic and anaerobic bacteria (including antibiotic-resistant strains), yeasts, and filamentous fungi during a 14-day test period. Based on our results, the silver-containing dressing is likely to provide a barrier to infection, in addition to providing proven fluid-handling benefits of the AQUACEL Hydrofiber dressing, in the management of partial-thickness burns.
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639
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Hills SA, Balkau B, Coppack SW, Dekker JM, Mari A, Natali A, Walker M, Ferrannini E. The EGIR-RISC STUDY (The European group for the study of insulin resistance: relationship between insulin sensitivity and cardiovascular disease risk): I. Methodology and objectives. Diabetologia 2004; 47:566-570. [PMID: 14968294 DOI: 10.1007/s00125-004-1335-5] [Citation(s) in RCA: 145] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2003] [Revised: 12/16/2003] [Indexed: 10/26/2022]
Abstract
AIMS/HYPOTHESES Insulin resistance is thought to be a key predictor for the development of Type 2 diabetes mellitus and cardiovascular disease (CVD), a leading cause of morbidity and premature mortality in Europe. Insulin resistance is influenced by both genetic and lifestyle factors (e.g. obesity and physical inactivity). The RISC (Relationship between Insulin Sensitivity and Cardiovascular disease) Study is using the infrastructure of an extended European collaborative research group to study insulin resistance and CVD risk in 1500 healthy people aged 30 to 60 years from 20 centres in 13 countries. METHODS Baseline measurements of glucose tolerance and insulin sensitivity are made by the oral glucose tolerance test and the euglycaemic insulin clamp, respectively; carotid artery intima-medial thickness (by ultrasound), ankle/brachial pressure index and electrocardiography will enable evaluation of subclinical CVD at baseline and at follow-up. Classic CVD risk factors, as well as socioeconomic and lifestyle factors will be recorded at baseline; samples for measurement of biochemical and genetic markers will be collected and stored for future analyses. Investigations will be repeated after 3 and 10 years to evaluate the relationship between insulin resistance and the development of atherosclerosis as measured by carotid artery intima-media thickness. Development of Type 2 diabetes, dyslipidaemia, obesity, hypertension and cardiovascular events are additional endpoints. CONCLUSIONS This study will evaluate the importance of insulin resistance in the development of CVD and diabetes, and has implications for the development of prevention and treatment strategies.
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640
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Lowe GDO, Danesh J, Lewington S, Walker M, Lennon L, Thomson A, Rumley A, Whincup PH. Tissue plasminogen activator antigen and coronary heart disease Prospective study and meta-analysis. Eur Heart J 2004; 25:252-9. [PMID: 14972427 DOI: 10.1016/j.ehj.2003.11.004] [Citation(s) in RCA: 124] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2003] [Revised: 10/28/2003] [Accepted: 11/06/2003] [Indexed: 11/22/2022] Open
Abstract
AIMS To determine whether circulating tissue plasminogen activator (t-PA) antigen concentrations are prospectively related to risk of coronary heart disease (CHD) in the general population. METHODS AND RESULTS We measured baseline concentrations of t-PA antigen in the stored serum samples of 606 CHD cases and 1227 controls 'nested' in a prospective cohort of 5661 men monitored for 16 years, and conducted a meta-analysis of previous relevant studies to place our findings in context. Tissue plasminogen activator antigen values were strongly correlated with several vascular risk factors, including serum lipids, body mass index, alcohol consumption, and markers of systemic inflammation. In a comparison of men in the top third compared with those in the bottom third of baseline t-PA antigen values, the odds ratio for CHD was 2.20 (95% confidence interval (CI) 1.70-2.85) after adjustment for age and town only, but this fell to 1.48 (1.09-2.01) after further adjustment. Analysis of t-PA as a continuous variable gave similar results. Similarly, when published information on all seven available prospective cohort studies in general populations (2119 cases and 8832 controls in total) was synthesized, the combined odds ratio was 2.18 (1.77-2.69) after adjustment for age and sex only, and this fell to 1.47 (1.19-1.81) after further adjustment. CONCLUSION Although there is a statistically significant association between circulating concentrations of t-PA antigen and subsequent CHD, additional studies are needed to determine to what extent this is independent from more established risk factors.
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641
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Antunes F, Walker M, Moyle GJ. Efficacy and Tolerability of Zalcitabine Twice Daily (HIVBID Study). J Acquir Immune Defic Syndr 2004; 35:205-6. [PMID: 14722456 DOI: 10.1097/00126334-200402010-00017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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642
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Bult CJ, Blake JA, Richardson JE, Kadin JA, Eppig JT, Baldarelli RM, Barsanti K, Baya M, Beal JS, Boddy WJ, Bradt DW, Burkart DL, Butler NE, Campbell J, Corey R, Corbani LE, Cousins S, Dene H, Drabkin HJ, Frazer K, Garippa DM, Glass LH, Goldsmith CW, Grant PL, King BL, Lennon-Pierce M, Lewis J, Lu I, Lutz CM, Maltais LJ, McKenzie LM, Miers D, Modrusan D, Ni L, Ormsby JE, Qi D, Ramachandran S, Reddy TBK, Reed DJ, Sinclair R, Shaw DR, Smith CL, Szauter P, Taylor B, Vanden Borre P, Walker M, Washburn L, Witham I, Winslow J, Zhu Y. The Mouse Genome Database (MGD): integrating biology with the genome. Nucleic Acids Res 2004; 32:D476-81. [PMID: 14681461 PMCID: PMC308859 DOI: 10.1093/nar/gkh125] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The Mouse Genome Database (MGD) is one component of the Mouse Genome Informatics (MGI) system (http://www.informatics.jax.org), a community database resource for the laboratory mouse. MGD strives to provide a comprehensive knowledgebase about the mouse with experiments and data annotated from both literature and online sources. MGD curates and presents consensus and experimental data representations of genetic, genotype (sequence) and phenotype information including highly detailed reports about genes and gene products. Primary foci of integration are through representations of relationships between genes, sequences and phenotypes. MGD collaborates with other bioinformatics groups to curate a definitive set of information about the laboratory mouse and to build and implement the data and semantic standards that are essential for comparative genome analysis. Recent developments in MGD discussed here include an extensive integration of the mouse sequence data and substantial revisions in the presentation, query and visualization of sequence data.
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643
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Wannamethee SG, Lawlor DA, Whincup PH, Walker M, Ebrahim S, Davey-Smith G. Birthweight of offspring and paternal insulin resistance and paternal diabetes in late adulthood: cross sectional survey. Diabetologia 2004; 47:12-8. [PMID: 14647894 DOI: 10.1007/s00125-003-1270-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2003] [Revised: 09/08/2003] [Indexed: 10/26/2022]
Abstract
AIMS/HYPOTHESIS It has been proposed that genetic factors involved in insulin action could explain part of the link between low birthweight and risk of cardiovascular disease and diabetes in adulthood. To confirm this we examined the association between offspring birthweight and paternal insulin resistance and diabetes in late adulthood. METHODS We did a cross-sectional survey of 4252 men who were 60 to 79 years of age and from 24 British towns. Of these, 2788 men provided details of their offsprings' birthweight and sex. RESULTS Offspring birthweight was inversely associated with paternal insulin resistance defined by the homeostasis model assessment (HOMA) score and with Type 2 diabetes in late adulthood. Fathers of offspring in the highest quartile of sex-standardised birthweight SD scores had a 34% reduction in odds of having a high HOMA insulin resistance score (OR=0.66, 95% CI: 0.47 to 0.92) compared with fathers of offspring in the lowest quartile after adjustment for potential confounders. A stronger inverse association was seen between offspring birthweight and risk of paternal diabetes (adjusted OR=0.59, 95% CI: 0.39 to 0.88 top quartile vs lowest quartile). For each increase of offspring-birthweight SD score the odds of high HOMA scores decreased by 13% (OR=0.87, 95% CI: 0.78 to 0.98) and the odds for diabetes by 17% (OR=0.83, 95% CI: 0.72 to 0.95), after full adjustment. CONCLUSIONS/INTERPRETATION Offspring birthweight is inversely associated with paternal insulin resistance and diabetes in late adulthood, supporting the hypothesis that genetic factors related to insulin action contribute to the association between birthweight and adult cardiovascular disease and diabetes risk.
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644
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Morris RW, Whincup PH, Emberson JR, Lampe FC, Walker M, Shaper AG. North-South Gradients in Britain for Stroke and CHD. Stroke 2003; 34:2604-9. [PMID: 14551398 DOI: 10.1161/01.str.0000092489.98235.1d] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background and Purpose—
The geographic variation in CHD and stroke within Great Britain is well known. We aimed to quantify these variations and to determine the contribution of established risk factors.
Methods—
This prospective study consisted of 7735 men 40 to 59 years of age in 24 British towns who were followed up for 20 years from screening in 1978 to 1980. We compared age-adjusted incidences of major stroke and CHD events in southern England and the rest of Britain before and after adjustment for established cardiovascular risk factors.
Results—
At least 1 episode of stroke occurred in 467 men (3.54 per 1000 person-years, age standardized) and of CHD in 1299 men (10.05 per 1000 person-years). Event rates varied between towns, from 2.00 to 5.45 per 1000 person-years for stroke and from 6.16 to 12.21 per 1000 person-years for CHD. Incidence for both diseases was highest in Scottish towns and lowest in southern English towns (“north-south gradient”). The hazard ratio for stroke in the rest of Britain compared with southern England was 1.44 (95% confidence interval [CI], 1.16 to 1.78); for CHD, it was 1.32 (95% CI, 1.14 to 1.53). After adjustment for baseline systolic blood pressure, smoking status, physical activity, social class, and height, the hazard ratio was 1.24 (95% CI, 1.00 to 1.54) for stroke and 1.17 (95% CI, 1.02 to 1.35) for CHD.
Conclusions—
Similar north-south gradients were observed for major stroke and major CHD events. The magnitude of these gradients was considerably diminished when individual risk variables were taken into account.
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645
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Sharpe RM, Fraser HM, Brougham MFH, McKinnell C, Morris KD, Kelnar CJH, Wallace WHB, Walker M. Role of the neonatal period of pituitary-testicular activity in germ cell proliferation and differentiation in the primate testis. Hum Reprod 2003; 18:2110-7. [PMID: 14507830 DOI: 10.1093/humrep/deg413] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The neonatal period of pituitary-testicular activity (NPTA) in human males has been hypothesized to play a role in germ cell proliferation and differentiation and to be defective in cryptorchid testes. The present study was carried out to establish in the marmoset if suppression of the NPTA, by treatment with a GnRH antagonist, results in impaired germ cell proliferation and/or differentiation. METHODS Comparison of germ cell (GC) numbers and differentiation from gonocytes to pre-spermatogonia and spermatogonia, at birth (in controls) and at the end of the NPTA in marmoset co-twin males treated from birth to age 14 weeks with vehicle or GnRH antagonist. RESULTS From birth to age 18-24 weeks, testis weight increased approximately 5-fold and GC number approximately 10-fold, including increased numbers of gonocytes and pre-spermatogonia and the first appearance of spermatogonia. Treatment with GnRH antagonist attenuated the increase in testis weight and GC numbers, but the effect was only partial (24-30% reduction), and the relative proportions of gonocytes, pre-spermatogonia and spermatogonia in the GnRH antagonist-treated group were unchanged from control values. CONCLUSIONS The NPTA plays only a minor, if any, role in GC proliferation and differentiation in the marmoset. The changes in GnRH antagonist-treated co-twins may reflect impaired GC survival due to withdrawal of gonadotrophin support for Sertoli cells. These findings do not support a pivotal role for the NPTA in neonatal GC development in primates.
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646
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O'Neill MAA, Vine GJ, Beezer AE, Bishop AH, Hadgraft J, Labetoulle C, Walker M, Bowler PG. Antimicrobial properties of silver-containing wound dressings: a microcalorimetric study. Int J Pharm 2003; 263:61-8. [PMID: 12954181 DOI: 10.1016/s0378-5173(03)00361-2] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The studies reported here have been undertaken to assess the potential use of isothermal microcalorimetry in studying the antimicrobial efficacy of wound dressings that contain antimicrobial agents. The microcalorimetric technique allows non-invasive and non-destructive analysis to be performed directly on a test sample, regardless of whether it is homogeneous or heterogeneous in nature. Microcalorimetry is an established procedure that offers quantitative measurements and has the distinct advantage over traditional antimicrobial test methodologies in that calorimetric measurements are made continuously over real-time, thus the dynamic response of microorganisms to an antimicrobial agent is observed in situ. The results described in this paper are for interaction of two silver-containing wound care products AQUACEL Ag Hydrofiber (ConvaTec, Deeside, UK) and Acticoat 7 with SILCRYST (Smith and Nephew Healthcare, UK) with the wound pathogenic organisms Staphylococcus aureus and Pseudomonas aeruginosa. Both dressings are shown, microcalorimetrically, to have the capacity to kill these common wound pathogens within 1-2 h of contact. A dose-response study was conducted with the AQUACEL Ag dressing. Microcalorimetry is shown to be rapid, simple and effective in the study of the antimicrobial properties of gel forming wound dressings.
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647
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Walker M, Jourdan P. Resource‐based sustainable development: an alternative approach to industrialisation in South Africa. ACTA ACUST UNITED AC 2003. [DOI: 10.1080/14041040310019435] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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648
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Abstract
In the last decade, the development of Barker's hypothesis of fetal programming opened the field for extensive research into the fetal origin of adult diseases. The association between low birth weight, which reflects intrauterine nutritional status, and the development of adult diseases has been confirmed in many studies for type 2 diabetes, hypertension and coronary heart diseases. Many other adulthood diseases were investigated for the same association with variable outcomes. These will be presented in this review.
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649
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Swinebroad EL, Dabareiner RM, Swor TM, Carter GK, Watkins JP, Walker M, Schmitz DG, Honnas CM. Osteomyelitis secondary to trauma involving the proximal end of the radius in horses: five cases (1987-2001). J Am Vet Med Assoc 2003; 223:486-91. [PMID: 12930087 DOI: 10.2460/javma.2003.223.486] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine clinical, radiographic, and scintigraphic abnormalities in and treatment and outcome of horses with trauma-induced osteomyelitis of the proximal aspect of the radius. DESIGN Retrospective study. ANIMALS 5 horses. PROCEDURE Data collected from the medical records included signalment; history; horse use; degree of lameness; radiographic, ultrasonographic, and scintigraphic findings; treatment; and outcome. RESULTS Duration of lameness prior to referral ranged from 14 to 60 days. Mean severity of lameness was grade 3 of 5, and all horses had a single limb affected. All horses had signs of pain during elbow joint manipulation and digital palpation over the lateral aspect of the proximal end of the radius. Radiographic lesions consisted of periosteal proliferation, osteolysis, and subchondral bone lysis. Scintigraphy in 3 horses revealed intense pharmaceutical uptake diffusely involving the proximal end of the radius. Two horses had sepsis of the elbow joint. All horses were treated with antimicrobials long-term; 1 horse was also treated by local perfusion of the radial medullary cavity through an indwelling cannulated screw. At follow-up, all horses had returned to their previous function. CONCLUSIONS AND CLINICAL RELEVANCE Results suggest that osteomyelitis of the proximal end of the radius can result from a traumatic injury to the antebrachium. Because lesions may be an extension of septic arthritis, a thorough examination of the wound area and elbow joint is recommended. Prolonged systemic antimicrobial treatment can result in a successful outcome.
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650
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Parsons D, Bowler PG, Walker M. Polishing the information on silver. OSTOMY/WOUND MANAGEMENT 2003; 49:10-1; author reply 11-2, 14, 16 passim. [PMID: 14631658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
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