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Abstract
OBJECTIVES To evaluate the effects of gender, sex orientation, age, relationship status, age at first sex education, age at first sex, frequency of sex and number of sexual partners on the likelihood of unprotected sex in the United Kingdom (UK). METHODS A web-based survey was conducted in the UK in 2004 with 10,138 respondents. Eight variables were chosen as potential predictors of unprotected sex. Responses from sexually active participants were combined and crude/adjusted odds ratios (AORs) were calculated for binary/categorical variables. RESULTS No differences were found in AOR for gender, sex orientation, relationship status and frequency of sex. Differences were found in AOR for age, sex education, age at first sex and number of sexual partners, e.g. AOR 21-24 years of age versus under 16 (1.92, CI 1.38-2.68; p-value < 0.001); AOR sex education never received versus first sex education under 10 years of age (1.45, CI 1.12-1.87; p-value < 0.01); AOR first sex at 20 years versus at 14 years (0.56, CI 0.40-0.79; p-value < 0.01); and AOR 11-20 partners versus one partner (24.91, CI 20.02-30.98; p-value < 0.001). The association of sex orientation and relationship status with unprotected sex is confounded by the number of sexual partners. CONCLUSIONS UK health and education authorities should develop strategies to provide sex education starting in primary school and continuing throughout secondary school. Prevention programs and policies should focus on particular sexual behaviours. Furthermore, an understanding of sexual diversity and reducing stigmatisation of sexual orientation is necessary.
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Naumovski N, Roach P. Abstract: 1488 EPIGALLOCATECHIN GALLATE LOWERS CHOLESTEROL IN THE CHOLESTEROL-FED RABBIT BY UPREGULATING THE LDL RECEPTOR AND INHIBITING CHOLESTEROL SYNTHESIS AT THE LEVEL OF SQUALENE EPOXIDASE. ATHEROSCLEROSIS SUPP 2009. [DOI: 10.1016/s1567-5688(09)70449-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Koc Y, de Mello AJ, McHale G, Newton MI, Roach P, Shirtcliffe NJ. Nano-scale superhydrophobicity: suppression of protein adsorption and promotion of flow-induced detachment. LAB ON A CHIP 2008; 8:582-586. [PMID: 18369513 DOI: 10.1039/b716509a] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Wall adsorption is a common problem in microfluidic devices, particularly when proteins are used. Here we show how superhydrophobic surfaces can be used to reduce protein adsorption and to promote desorption. Hydrophobic surfaces, both smooth and having high surface roughness of varying length scales (to generate superhydrophobicity), were incubated in protein solution. The samples were then exposed to flow shear in a device designed to simulate a microfluidic environment. Results show that a similar amount of protein adsorbed onto smooth and nanometer-scale rough surfaces, although a greater amount was found to adsorb onto superhydrophobic surfaces with micrometer scale roughness. Exposure to flow shear removed a considerably larger proportion of adsorbed protein from the superhydrophobic surfaces than from the smooth ones, with almost all of the protein being removed from some nanoscale surfaces. This type of surface may therefore be useful in environments, such as microfluidics, where protein sticking is a problem and fluid flow is present. Possible mechanisms that explain the behaviour are discussed, including decreased contact between protein and surface and greater shear stress due to interfacial slip between the superhydrophobic surface and the liquid.
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Fontes M, Roach P. T10-O-05 Age at first sex: when does it really happen? SEXOLOGIES 2008. [DOI: 10.1016/s1158-1360(08)72904-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Roach P, McHale G, Evans CR, Shirtcliffe NJ, Newton MI. Decoupling of the liquid response of a superhydrophobic quartz crystal microbalance. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:9823-30. [PMID: 17705513 DOI: 10.1021/la701089a] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Recent reports using particle image velocimetry and cone-and-plate rheometers have suggested that a simple Newtonian liquid flowing across a superhydrophobic surface demonstrates a finite slip length. Slippage on a superhydrophobic surface indicates that the combination of topography and hydrophobicity may have consequences for the coupling at the solid--liquid interface observed using the high-frequency shear-mode oscillation of a quartz crystal microbalance (QCM). In this work, we report on the response of a 5 MHz QCM possessing a superhydrophobic surface to immersion in water--glycerol mixtures. QCM surfaces were prepared with a layer of SU-8 photoresist and lithographically patterned to produce square arrays of 5 mum diameter circular cross-section posts spaced 10 microm center-to-center and with heights of 5, 10, 15, and 18 microm. Non-patterned layers were also created for comparison, and both non-hydrophobized and chemically hydrophobized surfaces were investigated. Contact angle measurements confirmed that the hydrophobized post surfaces were superhydrophobic. QCM measurements in water before and after applying pressure to force a Cassie-Baxter (non-penetrating) to Wenzel (penetrating) conversion of state showed a larger frequency decrease and higher dissipation in the Wenzel state. QCM resonance spectra were fitted to a Butterworth-van Dyke model for the full range of water-glycerol mixtures from pure water to (nominally) pure glycerol, thus providing data on both energy storage and dissipation. The data obtained for the post surfaces show a variety of types of behavior, indicating the importance of the surface chemistry in determining the response of the quartz crystal resonance, particularly on topographically structured surfaces; data for hydrophobized post surfaces imply a decoupling of the surface oscillation from the mixtures. In the case of the 15 microm tall hydrophobized post surfaces, crystal resonance spectra become narrower as the viscosity-density product increases, which is contrary to the usual behavior. In the most extreme case of the 18 microm tall hydrophobized post surfaces, both the frequency decrease and bandwidth increase of the resonance spectra are significantly lower than that predicted by the Kanazawa and Gordon model, thus implying a decoupling of the oscillating surface from the liquid, which can be interpreted as interfacial slip.
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Roach P, Malone JK. Comparison of insulin lispro mixture 25/75 with insulin glargine during a 24-h standardized test-meal period in patients with Type 2 diabetes. Diabet Med 2006; 23:743-9. [PMID: 16842478 DOI: 10.1111/j.1464-5491.2006.01895.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIM To compare insulin lispro mixture (25% insulin lispro and 75% NPL; Mix 25/75) twice-daily plus oral glucose-lowering medications (metformin and/or sulphonylurea) with once-daily insulin glargine plus oral agents with respect to postprandial glycaemic control and other glucose and lipid parameters in patients with Type 2 diabetes inadequately controlled with insulin and/or oral glucose-lowering agents. METHODS This was a randomized, open-label, crossover study. Prestudy oral agents were continued and patients not already on oral agents were treated with metformin. Mix 25/75 and insulin glargine were adjusted over 3 months to attain premeal plasma glucose (PG) < 6.0 mmol/l and were then given during a 24-h in-patient test meal period with frequent PG, serum triglyceride (TG) and free fatty acid (FFA) measurements. RESULTS Twenty patients (10 F/10 M; mean +/-sd age 54.0 +/- 10.7 years, body mass index 37.0 +/- 8.6 kg/m2, HbA1c 8.4 +/- 1.01%) participated. Mean doses were 23 U before the morning and 37 U before the evening meal for Mix 25/75 and 44 U for insulin glargine. The combined 2-h morning and evening meal postprandial plasma glucose (PPG) was not different between groups (9.2 +/- 2.04 vs. 9.9 +/- 1.66 mmol/l, P = 0.161). Mix 25/75 was associated with a lower mean 2-h PPG for all meals combined (9.0 +/- 1.88 vs. 9.9 +/- 1.80 mmol/l, P < 0.05) and lower mean 24-h PG (6.7 +/- 1.00 vs. 7.5 +/- 1.32 mmol/l, P < 0.01). Eight patients experienced mild hypoglycaemia (PG < 3.5 mmol/l) with Mix 25/75 and 3 with insulin glargine. The endpoint HbA1c was lower with Mix 25/75 (6.9 +/- 0.52% vs. 7.3 +/- 0.81%, P < 0.05). CONCLUSIONS In a 24-h test-meal setting in 20 patients, Mix 25/75 insulin plus oral glucose-lowering agents was associated with lower mean PPG and 24-h PG, more mild hypoglycaemia and similar TG, FFA and fasting PG concentrations. HbA1c was lower with Mix 75/25 plus oral agents, although it may not have reached steady state due to ongoing dose adjustment.
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Ryan MJ, Stern GA, Diamond M, Croft MV, Roach P, Kidd K. Temporal trends of organochlorine contaminants in burbot and lake trout from three selected Yukon lakes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2005; 351-352:501-22. [PMID: 16140362 DOI: 10.1016/j.scitotenv.2004.08.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2004] [Revised: 07/28/2004] [Accepted: 08/28/2004] [Indexed: 05/02/2023]
Abstract
Historical studies have demonstrated that organochlorine (OC) concentrations in top predators can vary considerably from lake to lake within a small geographic region but temporal trends of these contaminants have rarely been monitored in a sub-Arctic area for a long period of time. This study examined OC concentrations, including chlordane (CHL), DDT, hexachlorocyclohexane (HCH), toxaphene (CHB), PCB and chlorinated benzenes (CBz) in lake trout and burbot, from three Yukon lakes (Laberge, Kusawa, Quiet), over a span of 11 years (1992-2003). Temporal and spatial differences continue to exist in the OC concentrations of burbot and lake trout between these lakes. There is strong evidence that these contaminants are declining at various rates in lake trout (Salveninus namaycush) in Laberge, Kusawa and Quiet Lakes. For example, SigmaDDT concentrations have decreased 39%, 85% and 84% in Kusawa, Quiet and Laberge Lakes, respectively. Conversely, no consistent trends were observed in OC concentrations for burbot (Lota lota). For example, there is no evidence of a decline in toxaphene concentrations of Kusawa burbot yet a 58% decrease was observed in Laberge samples. Increases were also observed in the SigmaHCH levels of Kusawa Lake burbot, as well as increases in all OC groups (except SigmaHCH) for the Quiet Lake burbot samples. Decreases in burbot were evident in SigmaHCH and SigmaCHB for Lake Laberge fish and in SigmaCHL for Kusawa Lake samples. Spatial variations in OC levels are quite evident as Lake Laberge trout and burbot continued to maintain the highest levels over the eleven-year period from 1992 to 2003 followed by Kusawa Lake and then Quiet Lake. These differences were related to a variety of factors especially the species morphological characteristics such as log age, log weights and fish lipid content. A decreasing trend in Quiet and Laberge Lake trout lipid content, coupled with fluctuating condition factors and increases in body masses, suggest biotic changes may be occurring within the food webs due to fish population variations related to the cessation of commercial fishing or potentially an increase in lake plankton productivity related to annual climate variation. It is suspected that biotic factors rather than atmospheric inputs are the primary factors affecting the contaminant concentrations in lake trout and burbot in the study lakes.
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Lockhart WL, Stern GA, Low G, Hendzel M, Boila G, Roach P, Evans MS, Billeck BN, DeLaronde J, Friesen S, Kidd K, Atkins S, Muir DCG, Stoddart M, Stephens G, Stephenson S, Harbicht S, Snowshoe N, Grey B, Thompson S, DeGraff N. A history of total mercury in edible muscle of fish from lakes in northern Canada. THE SCIENCE OF THE TOTAL ENVIRONMENT 2005; 351-352:427-63. [PMID: 16169059 DOI: 10.1016/j.scitotenv.2004.11.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2004] [Revised: 06/05/2004] [Accepted: 11/27/2004] [Indexed: 05/04/2023]
Abstract
Subsistence fishing has been an important source of food for Native People in northern Canada since prehistoric time. Measurements of the levels of mercury in edible muscle of northern fish have been undertaken for over three decades in efforts to evaluate the risks of consuming northern fish. This report summarizes the data obtained from 7974 fish of 25 species from sites distributed from the Yukon to Labrador. The most abundant species were lake trout, lake whitefish, arctic char, walleye, northern pike and burbot. The question being asked was essentially "Are the fish safe to eat?" The results were used to support decisions on fishing and consumption of fish. They were sorted in several ways, into concentration ranges corresponding to human consumption guidelines, into political jurisdictions and into types of bedrock geology. Overall walleye, northern pike and lake trout, usually exceeded the subsistence consumption guideline of 0.2 microg g-1 total mercury and often exceeded the higher guideline of 0.5 microg g-1 total mercury for commercial sales of fish. Mercury in burbot, another facultative predator, was often lower but several still exceeding a guideline. Arctic char collections were mostly from anadromous populations and these had very low levels of mercury, presumably reflecting marine food sources. Lake whitefish were among the cleanest fish examined with 69 of 81 collections falling in the lowest range. Most collections were from sites in sedimentary rock. However a few sites were in metamorphic, intrusive or volcanic rocks and these, taken together, tended to have a higher proportion of sites in the higher ranges of mercury. These results indicate a widespread problem with mercury in subsistence fisheries for predator species of fish with the problem being most problematic for Nunavut.
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Roach P, Woodworth J, Gudat U, Cerimele B, Diebler F, Pein M, Dreyer M. A 75% insulin lispro/25% NPL mixture provides a longer duration of insulin activity compared with insulin lispro alone in patients with Type 1 diabetes. Diabet Med 2003; 20:946-52. [PMID: 14632722 DOI: 10.1046/j.1464-5491.2003.01100.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS To compare a new insulin formulation, high mix (HM) [75% lispro (LP) and 25% neutral protamine lispro (NPL)], to regular human insulin (HR) and LP with respect to glucose response and pharmacokinetics following a test meal in patients with Type 1 diabetes. METHODS After fasting overnight, patients received an intravenous insulin infusion to standardize blood glucose (BG) to 7.5 mmol/l (135 mg/dl). In a randomised, three-way crossover study, HR was injected 30 min before, and LP or HM was injected immediately before the test meal on three separate occasions. For each patient, LP and HR were administered at identical doses; the HM dose was one and one third times that of HR and LP to maintain the same dose of short or rapid-acting insulin. The insulin infusion was stopped 15 min after the insulin injection. Free insulin and BG concentrations were measured frequently for 7 h following the test meal. RESULTS HM and LP resulted in better glycaemic control than HR during the observation period. BG concentrations during the first 4-5 h did not differ between HM and LP. However, HM exhibited prolonged insulin activity relative to LP beyond 5 h, extending the duration of action by approximately 1 h, and resulting in lower overall BG concentrations when the 0-6- and 0-7-h intervals were considered. CONCLUSIONS Compared with LP, HM provided similar glycaemic control for up to 5 h and superior glycaemic control from 5 to 7 h following a standard test meal.
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Roach P, Arora V, Campaigne BN, Mattoo V, Rangwala S. Humalog Mix50 before carbohydrate-rich meals in type 2 diabetes mellitus. Diabetes Obes Metab 2003; 5:311-6. [PMID: 12940868 DOI: 10.1046/j.1463-1326.2003.00277.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIM To compare pre-meal injection of Humalog Mix50 (Mix50) and Humalog Mix25 (Humalog Mix75/25 in the US; Mix25) with respect to 2 h postprandial (2 h pp) blood glucose (BG) control after a carbohydrate-rich breakfast in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS One hundred and sixteen patients were enrolled in a 16-week crossover trial and received two treatment regimens in a randomized crossover fashion: (i) Mix50 before breakfast and Mix25 before the evening meal (Mix50/Mix25) and (ii) Mix25 before both breakfast and the evening meal (Mix25 twice daily). Insulin doses were adjusted according to stated glycaemic targets. After 6 and 8 weeks of treatment, the patient's usual morning insulin dose was administered, followed immediately by a test breakfast representative of the patient's usual breakfast meal. Fasting and 2 h pp BG concentrations were measured at the time of the test meal. Haemoglobin A1c (A1C) was measured, and information regarding hypoglycaemia (symptoms) was collected at the end of each treatment period. RESULTS Insulin doses were similar between treatments (morning = 31-33 U, evening = 26-28 U) at endpoint. Following the test breakfast, the 2 h pp BG was lower (10.9 +/- 0.3 mmol/l vs. 12.4 +/- 0.3 mmol/l, p = 0.0012) and the 2 h pp BG excursion was smaller (1.4 +/- 0.28 mmol/l vs. 3.5 +/- 0.28 mmol/l, p < 0.001) during treatment with Mix50/Mix25 than during treatment with Mix25 twice daily. There was no difference between the treatments with respect to fasting BG (Mix50/Mix25, 9.5 +/- 0.3 mmol/l vs. Mix25 twice daily, 8.9 +/- 0.3 mmol/l; p = NS), A1C (8.14% +/- 1.14% vs. 8.14% +/- 1.07%; p = NS) or the incidence of self-reported hypoglycaemia (34% vs. 23%; p = NS). CONCLUSIONS Compared with treatment with Mix25 twice daily, treatment with Mix50 before breakfast and Mix25 before the evening meal resulted in better pp glycaemic control following a carbohydrate-rich meal, and similar fasting BG, A1C and incidence of hypoglycaemia in patients with type 2 diabetes.
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Stone E, Roach P, Bernard E, Briggs G, Havryk A, Faulder K, Dennis C. Use of computed tomography pulmonary angiography in the diagnosis of pulmonary embolismin patients with an intermediate probability ventilation/perfusion scan. Intern Med J 2003; 33:74-8. [PMID: 12603578 DOI: 10.1046/j.1445-5994.2003.00345.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Computed tomography pulmonary -angiography (CTPA) plays an increasingly important role in the diagnosis of pulmonary embolism (PE). Although accurate in the detection of large PE, its accuracy in other patient groups is yet to be defined. AIM To compare CTPA with pulmonary angiography as a second-line investigation in patients with a ventilation/perfusion (VQ) scan indicating an intermediate probability of PE. METHODS We recruited 25 patients over a 17-month period. Subjects were eligible if they: (i). had clinically suspected PE, (ii). had a VQ scan indicating an intermediate probability of PE and (iii). were referred for pulmonary angiography. Subjects underwent CTPA within 36 h of the VQ scan. CTPA was interpreted without knowledge of the results of the pulmonary angiogram by two of the authors. RESULTS PE was prevalent (i.e. embolus detected at pulmonary angiography) in seven of 25 subjects (28%). The sensitivity of CTPA was 57% and the specificity was 94%. CONCLUSIONS In the setting of intermediate-probability VQ scanning, CTPA may be used to clarify the diagnosis of PE. However, a negative CTPA cannot -definitely exclude PE. Conventional pulmonary angiography may be necessary to determine the presence of PE if CTPA is negative.
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Blades B, Roach P, Lewis P. 3P-0832 The prevalence and treatment of hypercholesterolaemia in an Australian population sample. ATHEROSCLEROSIS SUPP 2003. [DOI: 10.1016/s1567-5688(03)91050-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Ollagnier-de Choudens S, Sanakis Y, Hewitson KS, Roach P, Münck E, Fontecave M. Reductive cleavage of S-adenosylmethionine by biotin synthase from Escherichia coli. J Biol Chem 2002; 277:13449-54. [PMID: 11834738 DOI: 10.1074/jbc.m111324200] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Biotin synthase (BioB) catalyzes the insertion of a sulfur atom between the C6 and C9 carbons of dethiobiotin. Reconstituted BioB from Escherichia coli contains a [4Fe-4S](2+/1+) cluster thought to be involved in the reduction and cleavage of S-adenosylmethionine (AdoMet), generating methionine and the reactive 5'-deoxyadenosyl radical responsible for dethiobiotin H-abstraction. Using EPR and Mössbauer spectroscopy as well as methionine quantitation we demonstrate that the reduced S = 1/2 [4Fe-4S](1+) cluster is indeed capable of injecting one electron into AdoMet, generating one equivalent of both methionine and S = 0 [4Fe-4S](2+) cluster. Dethiobiotin is not required for the reaction. Using site-directed mutagenesis we show also that, among the eight cysteines of BioB, only three (Cys-53, Cys-57, Cys-60) are essential for AdoMet reductive cleavage, suggesting that these cysteines are involved in chelation of the [4Fe-4S](2+/1+) cluster.
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Abstract
PURPOSE The aim of this study was to assess the diagnostic value of RBC scintigraphy in the evaluation of possible splenic hemangioma. MATERIALS AND METHODS RBC scintigraphy was performed on a patient with an incidental finding of a splenic mass on computed tomographic scanning. Early and delayed planar and SPECT images were obtained. RESULTS Delayed images revealed blood pooling of the splenic mass. This finding is similar to the characteristics seen in RBC scintigraphy for hepatic hemangioma. CONCLUSION RBC scintigraphy may be useful in the evaluation of possible splenic hemangioma.
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Hernández H, Hewitson KS, Roach P, Shaw NM, Baldwin JE, Robinson CV. Observation of the iron-sulfur cluster in Escherichia coli biotin synthase by nanoflow electrospray mass spectrometry. Anal Chem 2001; 73:4154-61. [PMID: 11569804 DOI: 10.1021/ac0102664] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Biotin synthase from Escherichia coli was analyzed by nanoflow electrospray ionization mass spectrometry. From solution conditions in which the protein is in its native state, a distribution of monomeric, dimeric, and tetrameric species was observed. The distribution of these species was sensitive to changes in ionic strength: in the positive ion spectrum, biotin synthase at low ionic strength (pH 7.0-8.5) yielded less than 10% dimer. The masses of the monomeric species were consistent with the presence of a [2Fe-2S] cluster with a mass difference of 175.3 Da from the apomonomer with one disulfide bond. Despite the molecular mass of the noncovalent dimer (77 kDa), it was possible to observe a dimeric species containing one iron-sulfur cluster in both positive and negative ion spectra. Additionally, observation of a series of charge states assigned to the apodimer indicated that binding of the iron-sulfur cluster was not required to maintain the dimer. Binding of Cu2+ to biotin synthase was also observed; in the presence of excess chelating agent, free metals were removed and the iron-sulfur cluster remained intact. Evidence for the coordination of the iron-sulfur cluster in biotin synthase was obtained in a tandem mass spectrometry experiment. A single charge state containing the cluster at m/z 2416.9 was isolated, and collision-induced dissociation resulted in sequential loss of sulfur and retention of Fe3+.
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Roach P, Strack T, Arora V, Zhao Z. Improved glycaemic control with the use of self-prepared mixtures of insulin lispro and insulin lispro protamine suspension in patients with types 1 and 2 diabetes. Int J Clin Pract 2001; 55:177-82. [PMID: 11351771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 04/05/2023] Open
Abstract
A total of 166 patients (102 type 1, 64 type 2) were randomised to insulin lispro (LP) combined with insulin lispro protamine suspension (NPL), an intermediate-acting formulation of LP, or to regular human insulin (HR) combined with human NPH insulin (NPH) in this open-label, parallel study. Insulin doses were similar at endpoint. Blood glucose (BG) measurements (before and two hours after meals, bedtime, 3 a.m.)(mmol/l) were lower with LP/NPL two hours after breakfast (8.84 +/- 0.32 vs 10.29 +/- 0.41, p < 0.001), before lunch (6.21 +/- 0.20 vs 7.10 +/- 0.31, p = 0.016), two hours after the evening meal (10.18 +/- 0.36 vs 7.86 +/- 0.28, p < 0.0.001), and at bedtime (7.85 +/- 0.28 vs 9.43 +/- 0.40, p = 001). HbA1c was lower for LP/NPL at endpoint (7.54 +/- 0.11% vs 7.92 +/- 0.10%, p = 0.019). There was no difference in hypoglycaemia or insulin antibody levels. LP/NPL resulted in better glycaemic control than HR/NPH without increasing the risk of hypoglycaemia.
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Roach P. Patient Satisfaction – The prime outcome. Physiotherapy 2001. [DOI: 10.1016/s0031-9406(05)61098-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Binasis A, Pratley S, Roach P, Bernard E, Aboud M, Tofler G. Increase in von willebrand factor with exercise: A potential mechanism of increased cardiovascular risk. Heart Lung Circ 2000. [DOI: 10.1046/j.1443-9506.2000.07352.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Gross G, Russell JD, Beumont PJ, Touyz SW, Roach P, Aslani A, Hansen RD, Allen BJ. Longitudinal study of patients with anorexia nervosa 6 to 10 years after treatment. Impact of adequate weight restoration on outcome. Ann N Y Acad Sci 2000; 904:614-6. [PMID: 10865814 DOI: 10.1111/j.1749-6632.2000.tb06525.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Ollagnier-De Choudens S, Sanakis Y, Hewitson KS, Roach P, Baldwin JE, Münck E, Fontecave M. Iron-sulfur center of biotin synthase and lipoate synthase. Biochemistry 2000; 39:4165-73. [PMID: 10747808 DOI: 10.1021/bi992090u] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Biotin synthase and lipoate synthase are homodimers that are required for the C-S bond formation at nonactivated carbon in the biosynthesis of biotin and lipoic acid, respectively. Aerobically isolated monomers were previously shown to contain a (2Fe-2S) cluster, however, after incubation with dithionite one (4Fe-4S) cluster per dimer was obtained, suggesting that two (2Fe-2S) clusters had combined at the interface of the subunits to form the (4Fe-4S) cluster. Here we report Mössbauer studies of (57)Fe-reconstituted biotin synthase showing that anaerobically prepared enzyme can accommodate two (4Fe-4S) clusters per dimer. The (4Fe-4S) cluster is quantitatively converted into a (2Fe-2S)(2+) cluster upon exposure to air. Reduction of the air-exposed enzyme with dithionite or photoreduced deazaflavin yields again (4Fe-4S) clusters. The (4Fe-4S) cluster is stable in both the 2+ and 1+ oxidation states. The Mössbauer and EPR parameters were DeltaE(q) = 1.13 mm/s and delta = 0.44 mm/s for the diamagnetic (4Fe-4S)(2+) and DeltaE(q) = 0.51 mm/s, delta = 0.85 mm/s, g(par) = 2.035, and g(perp) = 1.93 for the S = (1)/(2) state of (4Fe-4S)(1+). Considering that we find two (4Fe-4S) clusters per dimer, our studies argue against the early proposal that the enzyme contains one (4Fe-4S) cluster bridging the two subunits. Our study of lipoate synthase gave results similar to those obtained for BS: under strict anaerobiosis, lipoate synthase can accommodate a (4Fe-4S) cluster per subunit [DeltaE(q) = 1.20 mm/s and delta = 0.44 mm/s for the diamagnetic (4Fe-4S)(2+) and g(par) = 2.039 and g(perp) = 1.93 for the S = (1)/(2) state of (4Fe-4S)(1+)], which reacts with oxygen to generate a (2Fe-2S)(2+) center.
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Matlow AG, Harrison A, Monteath A, Roach P, Balfe JW. Nosocomial transmission of tuberculosis (TB) associated with care of an infant with peritoneal TB. Infect Control Hosp Epidemiol 2000; 21:222-3. [PMID: 10738995 DOI: 10.1086/501749] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Nosocomial transmission of tuberculosis (TB) after exposure to infected peritoneal fluid has not been described. We report the exposure of 111 healthcare workers to infected dialysate from an infant with TB peritonitis. Two (5%) of 39 primary-care nurses, but no doctors or environmental service workers, had apparent tuberculin skin test conversions, raising the concern that patients with peritoneal TB may be a source for nosocomial transmission of TB.
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Abbey M, Owen A, Suzakawa M, Roach P, Nestel PJ. Effects of menopause and hormone replacement therapy on plasma lipids, lipoproteins and LDL-receptor activity. Maturitas 1999; 33:259-69. [PMID: 10656504 DOI: 10.1016/s0378-5122(99)00054-7] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A cross-sectional study of ninety six women was conducted to examine the effect of menopause and hormone replacement therapy (HRT) on plasma lipids, lipoproteins and oxidation of low density lipoproteins. The sample consisted of 26 premenopausal women, 26 postmenopausal women taking no replacement hormones and 43 postmenopausal women on hormone replacement therapy. Postmenopausal women not taking replacement hormones had significantly higher plasma cholesterol, low density lipoprotein (LDL) cholesterol and lipoprotein[a] (Lp[a]) levels compared to premenopausal women or postmenopausal women on HRT [6.00 +/- 0.15, 5.36 +/- 0.17 (P < 0.01), 5.63 +/- 0.13 (P < 0.05) mmol/l, respectively for total cholesterol; 4.13 +/- 0.15, 3.64 +/- 0.15 (P < 0.05), 3.82 +/- 0.12 (P < 0.05) mmol/l, respectively for LDL-cholesterol; 48.19 +/- 9.90, 26.59 +/- 5.53 (P < 0.03), 25.12 +/- 4.62 (P < 0.03) mg/dl, respectively for Lp[a]]. The differences in LDL cholesterol concentrations were inversely related to changes in LDL receptor activity (r = -0.27, P < 0.01). HRT use was found to be associated with a significantly smaller LDL particle size. Plasma triglyceride was significantly higher in women on HRT (1.16 +/- 0.07 mmol/l) than in the premenopausal group (0.96 +/- 0.07) or postmenopausal group not using HRT (0.87 +/- 0.06). There were no differences in LDL oxidation between the groups when LDL was oxidised in the presence of copper. Nor was there any difference in the uptake of copper-oxidised or macrophage-modified LDL into J774 macrophages. These results confirm the effect of menopause and exogenous hormones on plasma lipids and lipoproteins, and suggest that HRT modifies the activity of the LDL receptor. Hormone replacement did not appear to protect LDL from oxidation.
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Roach P, Yue L, Arora V. Improved postprandial glycemic control during treatment with Humalog Mix25, a novel protamine-based insulin lispro formulation. Humalog Mix25 Study Group. Diabetes Care 1999; 22:1258-61. [PMID: 10480767 DOI: 10.2337/diacare.22.8.1258] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Humalog Mix25 is a manufactured premixed insulin formulation containing insulin lispro and a novel insulin lispro-protamine formulation (NPL) in a ratio of 25:75%. The objective of this study was to compare Humalog Mix25 to human insulin 30/70 (30% regular insulin/70% NPH) with respect to glycemic control. RESEARCH DESIGN AND METHODS Humalog Mix25 was compared with human insulin 30/70 in 89 individuals with type 2 diabetes during a 6-month randomized open-label two-period crossover study. Each insulin was administered twice daily, before the morning and evening meals. Information regarding self-monitored blood glucose (BG), hypoglycemic episodes (hypoglycemic signs or symptoms or BG < or = 3.0 mmol/l), insulin dose, and HbA1c was collected. RESULTS Treatment with Humalog Mix25 resulted in better postprandial glycemic control after the morning and evening meals compared with treatment with human insulin 30/70. Overall glycemic control and the incidence of hypoglycemia were comparable between the treatments. CONCLUSIONS In comparison to treatment with human insulin 30/70, twice daily administration of Humalog Mix25 resulted in improved postprandial glycemic control, similar overall glycemic control, and the convenience of dosing immediately before meals.
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