26
|
Otto JM, O'Doherty AF, Hennis PJ, Mitchell K, Pate JS, Cooper JA, Grocott MPW, Montgomery HE. Preoperative exercise capacity in adult inflammatory bowel disease sufferers, determined by cardiopulmonary exercise testing. Int J Colorectal Dis 2012; 27:1485-91. [PMID: 22842663 DOI: 10.1007/s00384-012-1533-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/01/2012] [Indexed: 02/04/2023]
Abstract
BACKGROUND AND AIMS Aerobic exercise capacity appears impaired in children with inflammatory bowel disease (IBD). Whether this holds true in adults with IBD is not known. Using cardiopulmonary exercise testing (CPET), we assessed anaerobic threshold (AT) in such patients comparing data with reference values and other elective surgical patients. We also sought to confirm whether the presence of a fistula further reduced AT. METHODS CPET was performed between November 2007 and December 2010 on patients awaiting abdominopelvic surgery. Gender-specific normal reference values were used for comparison. Unadjusted comparison between two groups was made using Mann-Whitney U test and by unpaired t test. Data were adjusted by analysis of covariance, using age and sex as covariates. Differences between patients' observed values and reference values were tested using paired t tests. RESULTS Four hundred and fourteen patients (234 male) were studied (mean ± SD age, 56.6 ± 16.4 years; weight, 74.2 ± 15.6 kg). Adjusted AT values in Crohn's disease (CD) were lower than colorectal cancer (11.4 ± 3.4 vs 13.2 ± 3.5 ml.kg(-1).min(-1), p = 0.03) and for all other colorectal disease groups combined (12.6 ± 3.5 ml.kg(-1).min(-1), p = 0.03). AT of Ulcerative colitis (UC) and CD patients together were reduced compared to population reference values (p < 0.05). CONCLUSION After adjusting for age and sex, CD patients had a reduced AT compared to patients with colorectal cancer and other colorectal disease groups combined. The pathogenesis of this low AT remains to be defined and warrants further investigation.
Collapse
|
27
|
Tang TS, Prior SL, Li KW, Ireland HA, Bain SC, Hurel SJ, Cooper JA, Humphries SE, Stephens JW. Association between the rs1050450 glutathione peroxidase-1 (C > T) gene variant and peripheral neuropathy in two independent samples of subjects with diabetes mellitus. Nutr Metab Cardiovasc Dis 2012; 22:417-425. [PMID: 21185702 DOI: 10.1016/j.numecd.2010.08.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2010] [Revised: 06/02/2010] [Accepted: 08/02/2010] [Indexed: 12/14/2022]
Abstract
Glutathione peroxidase-1 (GPx-1) is an endogenous anti-oxidant enzyme. The T allele of the GPx-1 rs1050450 (C > T) gene variant is associated with reduced enzyme activity. Our aim was to examine the association between this gene variant and peripheral neuropathy in two cross-sectional samples of subjects with diabetes: (i) 773 Caucasian subjects were genotyped from the UCL Diabetes and Cardiovascular disease Study (UDACS) and (ii) 382 Caucasian subjects from the Ealing Diabetes Study (EDS). Peripheral neuropathy status (and oxidised-LDL [Ox-LDL:LDL] and plasma Total Ant-ioxidant Status [TAOS] in UDACS), were analysed in relation to genotype. We observed that: (i) In UDACS, the odds ratio (OR) for peripheral neuropathy in the T allele carriers compared to the CC genotype was 1.61 [1.10-2.28], p = 0.01. This remained significant after adjustment for other risk factors. Ox-LDL:LDL ratio was significantly elevated in T allele carriers (CC vs. CT/TT: 16.3 ± 2.4 v 18.0 ± 2.9 U/mmol LDL, p = 0.02). (ii) In EDS, the OR for peripheral neuropathy in the T allele carriers compared to the CC genotype was 1.95 [1.11-3.42], p = 0.02. This remained significant after adjustment for other risk factors. In conclusion, we observed a significant association between the T allele and peripheral neuropathy and LDL oxidation. This is the first paper to examine the rs1050450 variant in two samples of Caucasian subjects with diabetes. Prospective analysis of the gene variant is required in diabetic and healthy cohorts with measured plasma markers of oxidative stress to investigate the described association further.
Collapse
|
28
|
Hawkins KR, Hansen KC, Schoeller DA, Cooper JA. Effect of exercise on the diurnal variation in energy substrate use during a high-fat diet. Eur J Appl Physiol 2012; 112:3775-85. [PMID: 22382668 DOI: 10.1007/s00421-012-2360-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2011] [Accepted: 02/14/2012] [Indexed: 10/28/2022]
Abstract
Aerobic exercise increases 24-h fat oxidation following initiation of a high-fat diet. The objective of this study is to examine the time course of increased fat oxidation under exercise and sedentary conditions. Eighteen healthy subjects completed a randomized crossover design (sedentary and exercise visits) staying for five consecutive days in a metabolic chamber each visit. On day 1, 30% of energy intake was from fat; days 2-5 had 50% of energy as fat. During exercise, subjects rode on a stationary cycle at 45% of VO2max for 1 h in the mornings and evenings. Respiratory gases and urinary nitrogen were collected to calculate macronutrient oxidation and non-protein respiratory exchange ratio (NPRER). This data, collected continuously (24-h periods), were subsequently divided into three time segments: (1) exercise + recovery (1000-1200 hours, 2100-2200 hours), (2) sleep (2300-0645 hours), and (3) wake (all remaining hours). NPRER on exercise versus sedentary visits was lower for the sleep segment (0.77 ± 0.01 01 vs. 0.81 ± 0.01, p < 0.001), higher for the exercise + recovery segment (0.88 ± 0.01 vs. 0.86 ± 0.01, p < 0.001), and was not different for the wake segment. Fat oxidation was significantly higher for exercise versus sedentary treatments during sleep (41 ± 2 vs. 31 ± 2 g), wake (62 ± 3 vs. 51 ± 3 g), and exercise + recovery segments (33 ± 3 vs.16 ± 1 g), but so was fat intake by design (171 ± 8 vs. 128 ± 7 g/d). Although exercise showed greater fat oxidation during all segments, dietary fat intake was also higher. Therefore, based on NPRER, the time of day during which the exercise treatment increased the ratio of fat to carbohydrate oxidation was during sleep.
Collapse
|
29
|
Talmud PJ, Cooper JA, Gaunt T, Holmes MV, Shah S, Palmen J, Drenos F, Shah T, Kumari M, Kivimaki M, Whittaker J, Lawlor DA, Day IN, Hingorani AD, Casas JP, Humphries SE. Variants of ADRA2A are associated with fasting glucose, blood pressure, body mass index and type 2 diabetes risk: meta-analysis of four prospective studies. Diabetologia 2011; 54:1710-9. [PMID: 21455730 PMCID: PMC3110279 DOI: 10.1007/s00125-011-2108-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Accepted: 02/08/2011] [Indexed: 11/28/2022]
Abstract
AIMS/HYPOTHESIS We quantified the effect of ADRA2A (encoding α-2 adrenergic receptor) variants on metabolic traits and type 2 diabetes risk, as reported in four studies. METHODS Genotype data for ADRA2A single nucleotide polymorphisms (SNPs) rs553668 and rs10885122 were analysed in >17,000 individuals (1,307 type 2 diabetes cases) with regard to metabolic traits and type 2 diabetes risk. Two studies (n = 9,437), genotyped using the Human Cardiovascular Disease BeadChip, provided 12 additional ADRA2A SNPs. RESULTS Rs553668 was associated with per allele effects on fasting glucose (0.03 mmol/l, p = 0.016) and type 2 diabetes risk (OR 1.17, 95% CI 1.04-1.31; p = 0.01). No significant association was observed with rs10885122. Of the 12 SNPs, several showed associations with metabolic traits. Overall, after variable selection, rs553668 was associated with type 2 diabetes risk (OR 1.38, 95% CI 1.09-1.73; p = 0.007). rs553668 (per allele difference 0.036 mmol/l, 95% CI 0.008-0.065) and rs17186196 (per allele difference 0.066 mmol/l, 95% CI 0.017-0.115) were independently associated with fasting glucose, and rs17186196 with fasting insulin and HOMA of insulin resistance (4.3%, 95% CI 0.6-8.1 and 4.9%, 95% CI 1.0-9.0, respectively, per allele). Per-allele effects of rs491589 on systolic and diastolic blood pressure were 1.19 mmHg (95% CI 0.43-1.95) and 0.61 mmHg (95% CI 0.11-1.10), respectively, and those of rs36022820 on BMI 0.58 kg/m(2) (95% CI 0.15-1.02). CONCLUSIONS/INTERPRETATION Multiple ADRA2A SNPs are associated with metabolic traits, blood pressure and type 2 diabetes risk. The α-2 adrenergic receptor should be revisited as a therapeutic target for reduction of the adverse consequences of metabolic trait disorders and type 2 diabetes.
Collapse
|
30
|
Smart MC, Dedoussis G, Yiannakouris N, Grisoni ML, Ken-Dror G, Yannakoulia M, Papoutsakis C, Louizou E, Mantzoros CS, Melistas L, Kontogianni MD, Cooper JA, Humphries SE, Talmud PJ. Genetic variation within IL18 is associated with insulin levels, insulin resistance and postprandial measures. Nutr Metab Cardiovasc Dis 2011; 21:476-84. [PMID: 20227263 PMCID: PMC3158674 DOI: 10.1016/j.numecd.2009.12.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2009] [Revised: 11/18/2009] [Accepted: 12/10/2009] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND AIMS IL-18 expression is up-regulated in atherosclerotic plaques, and higher levels are seen in obese and Type 2 Diabetic individuals. More recently, a possible role for IL-18 in glucose and energy homeostasis has been suggested. METHODS AND RESULTS We investigated variation within the IL18 gene and its association with measures of obesity and the metabolic syndrome. Five IL18 tagging single nucleotide polymorphisms (rs1946519, rs2043055, rs549908, rs360729, rs3882891) were selected and genotyped in the Gene-Diet Attica Investigation on childhood obesity (GENDAI) (age range 10-14 yrs); in young European men in the second European Atherosclerosis Research offspring Study (EARSII), an offspring study (age range 18-28 yrs) and in a group of healthy women from the Greek Obese Women study (GrOW) (age range 18-74 yrs). Six common haplotypes were observed. In GrOW, Hap6 (Frequency-2.6%) was associated with higher insulin levels (p<0.0001), estimates of HOMA(-Insulin Resistance) (p<0.0001) and HOMA(-β-cell) (p<0.0001) compared to the common haplotype Hap1 (Frequency-33.2%). In EARSII, rs2043055 was associated with peak and area under the curve triglycerides (p=0.001 and p=0.002, respectively) after an oral fat tolerance test in 'cases' but not 'controls'. None of the haplotypes were associated with measures of body fatness in any of the studies. CONCLUSION Association of IL18 variation with insulin levels and estimates of insulin resistance were only observed in our adult study, suggesting that the effects of IL-18 are only associated with increasing age. Taken together with the association of IL18 variants with post-prandial measures, this provides support for IL-18 as a metabolic factor.
Collapse
Key Words
- interleukin 18
- obesity
- insulin resistance
- single nucleotide polymorphisms
- genetic variants
- haplotypes
- auc, area under the curve
- catameri, catanzaro metabolic risk
- cvd, cardiovascular disease
- ci, confidence intervals
- chd, coronary heart disease
- earsii, european atherosclerosis research case control study
- fdr, false discovery rate
- gendai, gene-diet attica investigation on childhood obesity
- grow, greek obese women
- hwe, hardy–weinberg equilibrium
- homa, homeostasis model assessment
- iipga, innate immunity pga
- ir, insulin resistance
- il-18, interleukin 18
- ld, linkage disequilibrium
- mi, myocardial infarct
- maf, minor allele frequency
- oftt, oral fat tolerance test
- ogtt, oral glucose tolerance test
- quicki, quantitative insulin sensitivity check index
- snp, single nucleotide polymorphism
- tsnps, tagging single nucleotide polymorphisms
- t2d, type 2 diabetes
- utr, untranslated region
Collapse
|
31
|
Simmons MM, Spiropoulos J, Webb PR, Spencer YI, Czub S, Mueller R, Davis A, Arnold ME, Marsh S, Hawkins SAC, Cooper JA, Konold T, Wells GAH. Experimental classical bovine spongiform encephalopathy: definition and progression of neural PrP immunolabeling in relation to diagnosis and disease controls. Vet Pathol 2010; 48:948-63. [PMID: 21078883 DOI: 10.1177/0300985810387072] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Tissues from sequential-kill time course studies of bovine spongiform encephalopathy (BSE) were examined to define PrP immunohistochemical labeling forms and map disease-specific labeling over the disease course after oral exposure to the BSE agent at two dose levels. Study was confined to brainstem, spinal cord, and certain peripheral nervous system ganglia-tissues implicated in pathogenesis and diagnosis or disease control strategies. Disease-specific labeling in the brainstem in 39 of 220 test animals showed the forms and patterns observed in natural disease and invariably preceded spongiform changes. A precise temporal pattern of increase in labeling was not apparent, but labeling was generally most widespread in clinical cases, and it always involved neuroanatomic locations in the medulla oblongata. In two cases, sparse labeling was confined to one or more neuroanatomic nuclei of the medulla oblongata. When involved, the spinal cord was affected at all levels, providing no indication of temporal spread within the cord axis or relative to the brainstem. Where minimal PrP labeling occurred in the thoracic spinal cord, it was consistent with initial involvement of general visceral efferent neurons. Labeling of ganglia involved only sensory ganglia and only when PrP was present in the brainstem and spinal cord. These experimental transmissions mimicked the neuropathologic findings in BSE-C field cases, independent of dose of agent or stage of disease. The model supports current diagnostic sampling approaches and control measures for the removal and destruction of nervous system tissues in slaughtered cattle.
Collapse
|
32
|
Cooper JA, Watras AC, Paton CM, Wegner FH, Adams AK, Schoeller DA. Impact of exercise and dietary fatty acid composition from a high-fat diet on markers of hunger and satiety. Appetite 2010; 56:171-8. [PMID: 21035513 DOI: 10.1016/j.appet.2010.10.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2010] [Revised: 09/14/2010] [Accepted: 10/21/2010] [Indexed: 01/12/2023]
Abstract
To compare the effects of both dietary fatty acid composition and exercise vs. sedentary conditions on circulating levels of hunger and satiety hormones. Eight healthy males were randomized in a 2 × 2 crossover design. The four treatments were 3 days of HF diets (50% of energy) containing high saturated fat (22% of energy) with exercise (SE) or sedentary (SS) conditions, and high monounsaturated fat (30% of energy) with exercise (UE) or sedentary (US) conditions. Cycling exercise was completed at 45% of VO(2)max for 2h daily. On the third HF day, 20 blood samples were drawn over a 24h period for each hormone (leptin, insulin, ghrelin, and peptide YY (PYY)). A visual analog scale (VAS) was completed hourly between 0800 and 2200. Average 24h leptin and insulin levels were lower while 24h PYY was higher during exercise vs. sedentary conditions. FA composition did not differentially affect 24h hormone values. VAS scores for hunger and fullness did not differ between any treatment but did correlate with ghrelin, leptin, and insulin. High saturated or unsaturated fat diets did not differ with respect to markers of hunger or satiety. Exercise decreased 24h leptin and insulin while increasing PYY regardless of FA composition.
Collapse
|
33
|
Cooper JA, Watras AC, Shriver T, Adams AK, Schoeller DA. Influence of dietary fatty acid composition and exercise on changes in fat oxidation from a high-fat diet. J Appl Physiol (1985) 2010; 109:1011-8. [DOI: 10.1152/japplphysiol.01025.2009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Acute high-fat (HF) diets can lead to short-term positive fat balances until the body increases fat oxidation to match intake. The purpose of this study was to examine the effects of a HF diet, rich in either mono-unsaturated or saturated fatty acids (FAs) and exercise, on the rate at which the body adapts to a HF diet.13C-labeled oleate and 2H-labeled palmitate were also given to determine the contribution of exogenous vs. global fat oxidation. Eight healthy men (age of 18–45 yr; body mass index of 22 ± 3 kg/m2) were randomized in a 2 × 2 crossover design. The four treatments were a high saturated fat diet with exercise (SE) or sedentary (SS) conditions and a high monounsaturated fat diet with exercise (UE) or sedentary (US) conditions. Subjects stayed for 5 days in a metabolic chamber. All meals were provided. On day 1, 30% of energy intake was from fat, whereas days 2–5 had 50% of energy as fat. Subjects exercised on a stationary cycle at 45% of maximal oxygen uptake for 2 h each day. Respiratory gases and urinary nitrogen were collected to calculate fat oxidation. Change from day 1 to day 5 showed both exercise treatments increased fat oxidation (SE: 76 ± 30 g, P = 0.001; UE: 118 ± 31 g, P < 0.001), whereas neither sedentary condition changed fat oxidation (SS: −10 ± 33 g, P = not significant; US: 41 ± 14 g, P = 0.07). No differences for dietary FA composition were found. Exercise led to a faster adaptation to a HF diet by increasing fat oxidation and achieving fat balance by day 5. Dietary FA composition did not differentially affect 24-h fat oxidation.
Collapse
|
34
|
Ireland HA, Cooper JA, Talmud PJ, Hingorani AD, Kivimki M, Kumari M, Morris R, Tzoulaki I, Price J, Fowkes FG, Humphries SE. BAS/BSCR40 Coronary heart disease risk associated with the homozygous minor allele for endothelial protein C receptor Ser219Gly. BRITISH HEART JOURNAL 2010. [DOI: 10.1136/hrt.2010.205781.51] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
35
|
Wogman NA, Thomas CW, Cooper JA, Engelmann RJ, Perkins RW. Cosmic ray-produced radionuclides as tracers of atmospheric precipitation processes. Science 2010; 159:189-92. [PMID: 17792356 DOI: 10.1126/science.159.3811.189] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Through recent developments in instrumental analysis it is now possible to measure with good precision the rainwater concentrations of five short-lived radionuclides which are produced by cosmic ray spallation of atmospheric argon. These measurements provide a method for studying the in-cloud nucleation times and aerosol scavenging efficiencies, and promise to provide information onshort-term processes which occur in rain and snow formation.
Collapse
|
36
|
Taylor A, Wang D, Patel K, Whittall R, Wood G, Farrer M, Neely RDG, Fairgrieve S, Nair D, Barbir M, Jones JL, Egan S, Everdale R, Lolin Y, Hughes E, Cooper JA, Hadfield SG, Norbury G, Humphries SE. Mutation detection rate and spectrum in familial hypercholesterolaemia patients in the UK pilot cascade project. Clin Genet 2010; 77:572-80. [PMID: 20236128 DOI: 10.1111/j.1399-0004.2009.01356.x] [Citation(s) in RCA: 137] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Cascade testing using DNA-mutation information is now recommended in the UK for patients with familial hypercholesterolaemia (FH). We compared the detection rate and mutation spectrum in FH patients with a clinical diagnosis of definite (DFH) and possible (PFH) FH. Six hundred and thirty-five probands from six UK centres were tested for 18 low-density lipoprotein receptor gene (LDLR) mutations, APOB p.Arg3527Gln and PCSK9 p.Asp374Tyr using a commercial amplification refractory mutation system (ARMS) kit. Samples with no mutation detected were screened in all exons by single strand conformation polymorphism analysis (SSCP)/denaturing high performance liquid chromatography electrophoresis (dHPLC)/direct-sequencing, followed by multiplex ligation-dependent probe amplification (MLPA) to detect deletions and duplications in LDLR.The detection rate was significantly higher in the 190 DFH patients compared to the 394 PFH patients (56.3% and 28.4%, p > 0.00001). Fifty-one patients had inadequate information to determine PFH/DFH status, and in this group the detection rate was similar to the PFH group (25.5%, p = 0.63 vs PFH). Overall, 232 patients had detected mutations (107 different; 6.9% not previously reported). The ARMS kit detected 100 (44%) and the MLPA kit 11 (4.7%). Twenty-eight (12%) of the patients had the APOB p.Arg3527Gln and four (1.7%) had the PCSK9 p.Asp374Tyr mutation. Of the 296 relatives tested from 100 families, a mutation was identified in 56.1%. In 31 patients of Indian/Asian origin 10 mutations (two previously unreported) were identified. The utility of the ARMS kit was confirmed, but sequencing is still required in a comprehensive diagnostic service for FH. Even in subjects with a low clinical suspicion of FH, and in those of Indian origin, mutation testing has an acceptable detection rate.
Collapse
|
37
|
Thompson AR, Cooper JA, Ashton HA, Hafez H. Growth rates of small abdominal aortic aneurysms correlate with clinical events. Br J Surg 2010; 97:37-44. [PMID: 20013940 DOI: 10.1002/bjs.6779] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND This retrospective analysis of prospectively collected abdominal aortic aneurysm (AAA) screening data aimed to identify predictors of AAA-related events (surgery or death) with a view to better targeting of screening. METHODS For the interval 1984-2007, data for 1649 subjects with an AAA were collected prospectively as part of the Chichester AAA screening programme. This included serial aortic size measurements, blood pressure, risk factors for arterial disease and concurrent medications. AAA growth rates were adjusted for risk factor confounders using flexible hierarchical modelling. AAA growth distribution was analysed using Silverman's test of multimodality. RESULTS Some 1231 subjects met the inclusion criteria of having more than one scan and a surveillance interval of over 3 months. AAA growth showed a bimodal pattern with nearly 50 per cent of all aneurysms never progressing to surgery or rupture. Adjusted annual AAA growth rates of at least 2 mm significantly predicted AAA-related events. CONCLUSION This analysis identified a bimodal growth pattern for AAA, with a significant association between annual AAA growth rate of at least 2 mm and AAA-related events.
Collapse
|
38
|
Jackson D, White I, Kostis JB, Wilson AC, Folsom AR, Wu K, Chambless L, Benderly M, Goldbourt U, Willeit J, Kiechl S, Yarnell JWG, Sweetnam PM, Elwood PC, Cushman M, Psaty BM, Tracy RP, Tybjaerg-Hansen A, Haverkate F, de Maat MPM, Thompson SG, Fowkes FGR, Lee AJ, Smith FB, Salomaa V, Harald K, Rasi V, Vahtera E, Jousilahti P, D'Agostino R, Kannel WB, Wilson PWF, Tofler G, Levy D, Marchioli R, Valagussa F, Rosengren A, Wilhelmsen L, Lappas G, Eriksson H, Cremer P, Nagel D, Curb JD, Rodriguez B, Yano K, Salonen JT, Nyyssönen K, Tuomainen TP, Hedblad B, Engström G, Berglund G, Loewel H, Koenig W, Hense HW, Meade TW, Cooper JA, De Stavola B, Knottenbelt C, Miller GJ, Cooper JA, Bauer KA, Rosenberg RD, Sato S, Kitamura A, Naito Y, Iso H, Salomaa V, Harald K, Rasi V, Vahtera E, Jousilahti P, Palosuo T, Ducimetiere P, Amouyel P, Arveiler D, Evans AE, Ferrieres J, Juhan-Vague I, Bingham A, Schulte H, Assmann G, Cantin B, Lamarche B, Despres JP, Dagenais GR, Tunstall-Pedoe H, Lowe GDO, Woodward M, Ben-Shlomo Y, Davey Smith G, Palmieri V, Yeh JL, Meade TW, Rudnicka A, Brennan P, Knottenbelt C, Cooper JA, Ridker P, Rodeghiero F, Tosetto A, Shepherd J, Lowe GDO, Ford I, Robertson M, Brunner E, Shipley M, Feskens EJM, Di Angelantonio E, Kaptoge S, Lewington S, Lowe GDO, Sarwar N, Thompson SG, Walker M, Watson S, White IR, Wood AM, Danesh J. Systematically missing confounders in individual participant data meta-analysis of observational cohort studies. Stat Med 2009; 28:1218-37. [PMID: 19222087 PMCID: PMC2922684 DOI: 10.1002/sim.3540] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
One difficulty in performing meta-analyses of observational cohort studies is that the availability of confounders may vary between cohorts, so that some cohorts provide fully adjusted analyses while others only provide partially adjusted analyses. Commonly, analyses of the association between an exposure and disease either are restricted to cohorts with full confounder information, or use all cohorts but do not fully adjust for confounding. We propose using a bivariate random-effects meta-analysis model to use information from all available cohorts while still adjusting for all the potential confounders. Our method uses both the fully adjusted and the partially adjusted estimated effects in the cohorts with full confounder information, together with an estimate of their within-cohort correlation. The method is applied to estimate the association between fibrinogen level and coronary heart disease incidence using data from 154 012 participants in 31 cohorts.† Copyright © 2009 John Wiley & Sons, Ltd.
Collapse
|
39
|
Petrie Aronin CE, Cooper JA, Sefcik LS, Tholpady SS, Ogle RC, Botchwey EA. Osteogenic differentiation of dura mater stem cells cultured in vitro on three-dimensional porous scaffolds of poly(epsilon-caprolactone) fabricated via co-extrusion and gas foaming. Acta Biomater 2008; 4:1187-97. [PMID: 18434267 PMCID: PMC2654610 DOI: 10.1016/j.actbio.2008.02.029] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2007] [Revised: 12/31/2007] [Accepted: 02/26/2008] [Indexed: 10/22/2022]
Abstract
A novel scaffold fabrication method utilizing both polymer blend extrusion and gas foaming techniques to control pore size distribution is presented. Seventy-five per cent of all pores produced using polymer blend extrusion alone were less than 50microm. Introducing a gas technique provided better control of pore size distribution, expanding the range from 0-50 to 0-350microm. Varying sintering time, annealing temperature and foaming pressure also helped to reduce the percentage of pore sizes below 50microm. Scaffolds chosen for in vitro cellular studies had a pore size distribution of 0-300microm, average pore size 66+/-17microm, 0.54+/-0.02% porosity and 98% interconnectivity, measured by micro-computed tomography (microCT) analysis. The ability of the scaffolds to support osteogenic differentiation for subsequent cranial defect repair was evaluated by static and dynamic (0.035+/-0.006ms(-1) terminal velocity) cultivation with dura mater stem cells (DSCs). In vitro studies showed minimal increases in proliferation over 28 days in culture in osteogenic media. Alkaline phosphatase expression remained constant throughout the study. Moderate increases in matrix deposition, as assessed by histochemical staining and microCT analysis, occurred at later time points, days 21 and 28. Although constructs cultured dynamically showed greater mineralization than static conditions, these trends were not significant. It remains unclear whether bioreactor culture of DSCs is advantageous for bone tissue engineering applications. However, these studies show that polycaprolactone (PCL) scaffolds alone, without the addition of other co-polymers or ceramics, support long-term attachment and mineralization of DSCs throughout the entire porous scaffold.
Collapse
|
40
|
Dorfmeister B, Zeng WW, Dichlberger A, Nilsson SK, Schaap FG, Hubacek JA, Merkel M, Cooper JA, Lookene A, Putt W, Whittall R, Lee PJ, Lins L, Delsaux N, Nierman M, Kuivenhoven JA, Kastelein JJP, Vrablik M, Olivecrona G, Schneider WJ, Heeren J, Humphries SE, Talmud PJ. Effects of six APOA5 variants, identified in patients with severe hypertriglyceridemia, on in vitro lipoprotein lipase activity and receptor binding. Arterioscler Thromb Vasc Biol 2008; 28:1866-71. [PMID: 18635818 DOI: 10.1161/atvbaha.108.172866] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE The purpose of this study was to identify rare APOA5 variants in 130 severe hypertriglyceridemic patients by sequencing, and to test their functionality, since no patient recall was possible. METHODS AND RESULTS We studied the impact in vitro on LPL activity and receptor binding of 3 novel heterozygous variants, apoAV-E255G, -G271C, and -H321L, together with the previously reported -G185C, -Q139X, -Q148X, and a novel construct -Delta139 to 147. Using VLDL as a TG-source, compared to wild type, apoAV-G255, -L321 and -C185 showed reduced LPL activation (-25% [P=0.005], -36% [P<0.0001], and -23% [P=0.02]), respectively). ApoAV-C271, -X139, -X148, and Delta139 to 147 had little affect on LPL activity, but apoAV-X139, -X148, and -C271 showed no binding to LDL-family receptors, LR8 or LRP1. Although the G271C proband carried no LPL and APOC2 mutations, the H321L carrier was heterozygous for LPL P207L. The E255G carrier was homozygous for LPL W86G, yet only experienced severe hypertriglyceridemia when pregnant. CONCLUSIONS The in vitro determined function of these apoAV variants only partly explains the high TG levels seen in carriers. Their occurrence in the homozygous state, coinheritance of LPL variants or common APOA5 TG-raising variant in trans, appears to be essential for their phenotypic expression.
Collapse
|
41
|
Hunter T, Alexander CB, Cooper JA. Protein phosphorylation and growth control. CIBA FOUNDATION SYMPOSIUM 2008; 116:188-204. [PMID: 3000705 DOI: 10.1002/9780470720974.ch12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Many growth factor receptors and retroviral transforming proteins share the property of phosphorylating proteins on tyrosine. Several substrates for both types of protein-tyrosine kinase have been identified. Treatment of quiescent cells with growth factors such as EGF and PDGF, whose receptors have ligand-stimulated protein-tyrosine kinase activities, induces tyrosine phosphorylation of three proteins, p45, p42 and p41. Two phosphorylated forms of p42 are found, the more basic of which is present in some but not all cells transformed by viral protein-tyrosine kinases. p42 is rapidly (as early as 1 min) but transiently (decreased to baseline by 2h) phosphorylated following PGDF or EGF treatment of quiescent fibroblasts. At saturating levels of mitogen the stoichiometry of p42 phosphorylation is greater than 50%. p42 is a highly conserved, rare (0.002% of total cell protein), soluble cytoplasmic protein. IGF I and insulin, whose receptors also have ligand-stimulated protein-tyrosine kinase activity, induce p42 phosphorylation in appropriate cells. In the case of insulin this effect has been observed in cells with large numbers of insulin receptors. p42 is also phosphorylated in response to mitogens whose receptors lack protein-tyrosine kinase activity, for example 12-O-tetradecanoylphorbol-13-acetate (TPA) and thrombin. For TPA there is evidence that this is an indirect effect due to the activation of a protein-serine/threonine kinase. On the basis of the highly conserved nature of this response and its generality, it seems likely that tyrosine phosphorylation of p42 is important for at least early responses to mitogens.
Collapse
|
42
|
Miller GJ, Ireland HA, Cooper JA, Bauer KA, Morrissey JH, Humphries SE, Esnouf MP. Relationship between markers of activated coagulation, their correlation with inflammation, and association with coronary heart disease (NPHSII). J Thromb Haemost 2008; 6:259-67. [PMID: 17973650 DOI: 10.1111/j.1538-7836.2008.02819.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
OBJECTIVE To determine whether activation of coagulation increases in parallel with inflammation and whether coagulation activation markers (CAMs) are independently associated with coronary heart disease (CHD), in the prospective study, NPHSII. METHODS Surveillance of 2997 men between 50 and 63 years yielded 314 first CHD events during 36507 person-years of observation. The plasma levels of activated factor XII (FXIIa), the peptides released upon activation of factor X (FXpep) and factor IX (FIXpep), activated factor VII (FVIIa), prothrombin fragment 1 + 2 (F1 + 2) and fibrinopeptide A (FpA) served as indices of activity along the coagulation pathway. C reactive protein (CRP) provided a marker of inflammatory activity. RESULTS While borderline or significant correlations were identified for each CAM with inflammation, as determined by CRP levels, these did not reach as high a numerical value as was shown for fibrinogen with CRP. FVIIa and FIXpep possessed independent associations with CHD: a one SD increase in adjusted FIXpep and FVIIa level was associated with a relative hazard of 1.20 (95% CI 1.00-1.43) and 0.70 (CI 0.58-0.86), respectively, using a group including all CHD events, compared with 'no-event'. CONCLUSIONS Inflammation has significant but minimal impact upon CAMs of the extrinsic coagulation pathway. Reduced FVIIa and increased FIXpep levels were found to be significant, independent, predictors of CHD.
Collapse
|
43
|
Smith AJP, Cooper JA, Li LK, Humphries SE. INSIG2 gene polymorphism is not associated with obesity in Caucasian, Afro-Caribbean and Indian subjects. Int J Obes (Lond) 2007; 31:1753-5. [PMID: 17471297 DOI: 10.1038/sj.ijo.0803645] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A common polymorphism, rs7566605, 10 kb upstream of the insulin-induced gene 2 transcription start site has been associated with obesity in Caucasian and African-American populations, with the hypothesis that an alteration in gene expression results in elevated plasma triglyceride levels. The goal of this study was to verify the findings in a cohort of 2721 healthy Caucasian men (second Northwick Park Heart Study), and a separate study of 747 type 2 diabetic patients from Caucasian, Afro-Caribbean and Indian groups (University College London Diabetes and Cardiovascular Disease Study). The rs7566605 single-nucleotide polymorphism (SNP) was not related to plasma triglyceride levels in either study, and we found no association with body mass index or obesity in either cohort, despite having the power to detect the previously reported effect. This suggests that, at the least, the true size of the effect on obesity of this SNP is likely to be considerably less than reported previously.
Collapse
|
44
|
Danesh J, Erqou S, Walker M, Thompson SG, Tipping R, Ford C, Pressel S, Walldius G, Jungner I, Folsom AR, Chambless LE, Knuiman M, Whincup PH, Wannamethee SG, Morris RW, Willeit J, Kiechl S, Santer P, Mayr A, Wald N, Ebrahim S, Lawlor DA, Yarnell JWG, Gallacher J, Casiglia E, Tikhonoff V, Nietert PJ, Sutherland SE, Bachman DL, Keil JE, Cushman M, Psaty BM, Tracy RP, Tybjaerg-Hansen A, Nordestgaard BG, Frikke-Schmidt R, Giampaoli S, Palmieri L, Panico S, Vanuzzo D, Pilotto L, Simons L, McCallum J, Friedlander Y, Fowkes FGR, Lee AJ, Smith FB, Taylor J, Guralnik J, Phillips C, Wallace R, Blazer D, Khaw KT, Jansson JH, Donfrancesco C, Salomaa V, Harald K, Jousilahti P, Vartiainen E, Woodward M, D'Agostino RB, Wolf PA, Vasan RS, Pencina MJ, Bladbjerg EM, Jorgensen T, Moller L, Jespersen J, Dankner R, Chetrit A, Lubin F, Rosengren A, Wilhelmsen L, Lappas G, Eriksson H, Bjorkelund C, Cremer P, Nagel D, Tilvis R, Strandberg T, Rodriguez B, Bouter LM, Heine RJ, Dekker JM, Nijpels G, Stehouwer CDA, Rimm E, Pai J, Sato S, Iso H, Kitamura A, Noda H, Goldbourt U, Salomaa V, Salonen JT, Nyyssönen K, Tuomainen TP, Deeg D, Poppelaars JL, Meade T, Cooper J, Hedblad B, Berglund G, Engstrom G, Döring A, Koenig W, Meisinger C, Mraz W, Kuller L, Selmer R, Tverdal A, Nystad W, Gillum R, Mussolino M, Hankinson S, Manson J, De Stavola B, Knottenbelt C, Cooper JA, Bauer KA, Rosenberg RD, Sato S, Naito Y, Holme I, Nakagawa H, Miura H, Ducimetiere P, Jouven X, Crespo C, Garcia-Palmieri M, Amouyel P, Arveiler D, Evans A, Ferrieres J, Schulte H, Assmann G, Shepherd J, Packard C, Sattar N, Cantin B, Lamarche B, Després JP, Dagenais GR, Barrett-Connor E, Wingard D, Bettencourt R, Gudnason V, Aspelund T, Sigurdsson G, Thorsson B, Trevisan M, Witteman J, Kardys I, Breteler M, Hofman A, Tunstall-Pedoe H, Tavendale R, Lowe GDO, Ben-Shlomo Y, Howard BV, Zhang Y, Best L, Umans J, Onat A, Meade TW, Njolstad I, Mathiesen E, Lochen ML, Wilsgaard T, Gaziano JM, Stampfer M, Ridker P, Ulmer H, Diem G, Concin H, Rodeghiero F, Tosetto A, Brunner E, Shipley M, Buring J, Cobbe SM, Ford I, Robertson M, He Y, Ibanez AM, Feskens EJM, Kromhout D, Collins R, Di Angelantonio E, Kaptoge S, Lewington S, Orfei L, Pennells L, Perry P, Ray K, Sarwar N, Scherman M, Thompson A, Watson S, Wensley F, White IR, Wood AM. The Emerging Risk Factors Collaboration: analysis of individual data on lipid, inflammatory and other markers in over 1.1 million participants in 104 prospective studies of cardiovascular diseases. Eur J Epidemiol 2007; 22:839-69. [PMID: 17876711 DOI: 10.1007/s10654-007-9165-7] [Citation(s) in RCA: 132] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2007] [Accepted: 07/02/2007] [Indexed: 01/22/2023]
Abstract
Many long-term prospective studies have reported on associations of cardiovascular diseases with circulating lipid markers and/or inflammatory markers. Studies have not, however, generally been designed to provide reliable estimates under different circumstances and to correct for within-person variability. The Emerging Risk Factors Collaboration has established a central database on over 1.1 million participants from 104 prospective population-based studies, in which subsets have information on lipid and inflammatory markers, other characteristics, as well as major cardiovascular morbidity and cause-specific mortality. Information on repeat measurements on relevant characteristics has been collected in approximately 340,000 participants to enable estimation of and correction for within-person variability. Re-analysis of individual data will yield up to approximately 69,000 incident fatal or nonfatal first ever major cardiovascular outcomes recorded during about 11.7 million person years at risk. The primary analyses will involve age-specific regression models in people without known baseline cardiovascular disease in relation to fatal or nonfatal first ever coronary heart disease outcomes. This initiative will characterize more precisely and in greater detail than has previously been possible the shape and strength of the age- and sex-specific associations of several lipid and inflammatory markers with incident coronary heart disease outcomes (and, secondarily, with other incident cardiovascular outcomes) under a wide range of circumstances. It will, therefore, help to determine to what extent such associations are independent from possible confounding factors and to what extent such markers (separately and in combination) provide incremental predictive value.
Collapse
|
45
|
Govers-Riemslag JWP, Smid M, Cooper JA, Bauer KA, Rosenberg RD, Hack CE, Hamulyak K, Spronk HMH, Miller GJ, ten Cate H. The plasma kallikrein-kinin system and risk of cardiovascular disease in men. J Thromb Haemost 2007; 5:1896-903. [PMID: 17723129 DOI: 10.1111/j.1538-7836.2007.02687.x] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND The plasma kallikrein-kinin system (PKKS) has been implicated in cardiovascular disease, but activation of the PKKS has not been directly probed in individuals at risk of coronary heart disease (CHD) or stroke. OBJECTIVE To determine the involvement of the PKKS, including factor XI, in cardiovascular disease occurring in a nested case-control study from the Second Northwick Park Heart Study (NPHS-II). METHODS AND RESULTS After a median follow-up of 10.7 years, 287 cases of CHD and stroke had been recorded and 542 age-matched controls were selected. When FXIIa-C1 esterase inhibitor (C1-inhibitor) concentrations were divided into tertiles (lowest tertile as reference), the odds ratios (ORs) at 95% CIs for CHD were 0.52 (0.34-0.80) in the middle tertile and 0.73 (0.49-1.09) in the highest tertile (P = 0.01 for the overall difference; P = 0.01 for CHD and stroke combined). For kallikrein-C1-inhibitor complexes, the ORs for stroke were 0.29 (0.12-0.72) and 0.67 (0.30-1.52) in the middle and high tertiles, respectively (P = 0.02). FXIIa-C1-inhibitor and kallikrein-C1-inhibitor complexes were negatively related to smoking and fibrinogen (P < 0.005). FXIa-inhibitor complexes correlated strongly with FXIIa-inhibitor complexes. CONCLUSIONS Lower levels of inhibitory complexes of the PKKS enzymes and particularly of FXIIa contribute to the risk of CHD and stroke in middle-aged men. This observation supports the involvement of the PKKS in atherothrombosis.
Collapse
|
46
|
Cooper JA, Webb AW, Whitaker WG. Isotopic measurements in the Cape York Peninsula area, North Qeensland. ACTA ACUST UNITED AC 2007. [DOI: 10.1080/00167617508728898] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
47
|
Jago JB, Cooper JA, Corbett KD. First evidence for Ordovician igneous activity in the dial range trough, Tasmania. ACTA ACUST UNITED AC 2007. [DOI: 10.1080/00167617708728968] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
48
|
|
49
|
Cooper JA, Wells AT, Nicholas T. Dating of glauconite from the Ngalia Basin, Northern Territory, Australia∗. ACTA ACUST UNITED AC 2007. [DOI: 10.1080/00167617108728748] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
50
|
Parker AJ, Webb AW, Fanning CM, Oliver RL, Cooper JA, Daly S, Benbow MC, Blissett AH, Lemon NM, Ramsay R, Coin CDA, Mortimer GE, Bradley GM, Cohen P, James PR, Radke F, Giles CW, Goode ADT. Symposium on the Gawler Craton, 11 December 1979. ACTA ACUST UNITED AC 2007. [DOI: 10.1080/00167618008729117] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|