Association between ADAMTS13 polymorphisms and risk of cardiovascular events in chronic coronary disease

Introduction: Association between ADAMTS13 levels and cardiovascular events has been described recently. However, no genetic study of ADAMTS13 in coronary patients has been described. Materials and Methods: Based on related populations frequencies and functional studies, we tested three ADAMTS13 polymorphisms: C1342G (Q448E), C1852G (P618A) and C2699T (A900V) in a group of 560 patients enrolled in the Medical, Angioplasty, or Surgery Study II (MASS II), a randomized trial comparing treatments for patients with coronary artery disease (CAD) and preserved left ventricular function. The incidence of the 5-year end-points of death and death from cardiac causes, myocardial infarction, refractory angina requiring revascularization and cerebrovascular accident was determined for each polymorphim`s allele, genotype and haplotype. Risk was assessed with the use of logistic regression and Cox proportional-hazards model and multivariable adjustment was employed for possible confounders. Results: Clinical characteristics and received treatment of each genotype group were similar at baseline. In an adjusted model for cardiovascular risk variables, we were able to observe a significant association between ADAMTS13 900V variant and an increased risk of death (OR: 1,92 CI: 1,14-3,23, p = 0,015) or death from cardiac cause (OR: 2,67, CI: 1,59-4,49, p = 0,0009). No association between events and ADAMTS13 Q448E or P618A was observed. Conclusions: This first report studying the association between ADAMTS13 genotypes and cardiovascular events provides evidence for the association between ADAMTS13 900V variant and an increased risk of death in a population with multi-vessel CAD. (C) 2009 Elsevier Ltd. All rights reserved.

Applying linear time-varying constraints to econometric models: With an application to demand systems

When linear equality constraints are invariant through time they can be incorporated into estimation by restricted least squares. If, however, the constraints are time-varying, this standard methodology cannot be applied. In this paper we show how to incorporate linear time-varying constraints into the estimation of econometric models. The method involves the augmentation of the observation equation of a state-space model prior to estimation by the Kalman filter. Numerical optimisation routines are used for the estimation. A simple example drawn from demand analysis is used to illustrate the method and its application.

Physicians` attitudes and adherence to use of risk scores for primary prevention of cardiovascular disease: cross-sectional survey in three world regions

Objective: To evaluate physicians` attitudes and adherence to the use of risk scores in the primary prevention of cardiovascular disease (CVD). Design and methods: A cross-sectional survey of 2056 physicians involved in the primary prevention of CVD. Participants included cardiologists (47%), general practitioners (42%), and endocrinologists (11%) from several geographical regions: Brazil (n=968), USA (n=381), Greece (n=275), Chile (n=157), Venezuela (n=128), Portugal (n=42), The Netherlands (n=41), and Central America (Costa Rica, Panama, El Salvador and Guatemala; n=64). Results: The main outcome measure was the percentage of responses on a multiple-choice questionnaire describing a hypothetical asymptomatic patient at intermediate risk for CVD according to the Framingham Risk Score. Only 48% of respondents reported regular use of CVD risk scores to tailor preventive treatment in the case scenario. Of non-users, nearly three-quarters indicated that `It takes up too much of my time` (52%) or `I don`t believe they add value to the clinical evaluation` (21%). Only 56% of respondents indicated that they would prescribe lipid-lowering therapy for the hypothetical intermediate-risk patient. A significantly greater proportion of regular users than non-users of CVD risk scores identified the need for lipid-lowering therapy in the hypothetical patient (59 vs. 41%; p<0.0001).

Cardiovascular prevention in HIV patients: Results from a successful intervention program

Objectives: To analyze the effect of a prevention program oil the estimated cardiovascular risk calculated by three risk scores. Methods: We prospectively evaluated 87 HIV+ patients with elevated cardiovascular risk estimation. Framirigham (FIRS), PROCAM and National Cholesterol Education Program (ATP-III) were applied. Cardiovascular risk was defined as elevated if >10%. All patients received non-pharmacological (diet, exercise, smoking cessation) and, when appropriate, pharmacological therapy. Results: Mean age was 52 years, 92% were male, 39.1% were smokers, 70.1% had hypertension, 18.4% had diabetes. All patients were under HAART, 56.3% were receiving protease inhibitors (131). After 6 months, intervention was associated to significant changes oil triglycerides (298 242 and 206 +/- 135 mg/dL, p<0.05), total-cholesterol (224 +/- 47 and 189 +/- 38 mg/dL, p<0.001). LDL-cholesterol (129 +/- 44 and 109 +/- 30 mg/dL,p<0.001). Frequencies of patients with elevated cardiac risk before and 6 months after intervention were 92% x 27.6% (p < 0.0001), 80.5% x 50.6% (p < 0.0002), and 25.3% x 14.9% (p = 0.12), for FIRS, ATP III and PROCAM, respectively. Conclusions: An intervention Program focused on reduction of traditional risk factors was able to decrease the frequency of patients with HIV infection and elevated cardiovascular risk estimation. FIRS showed greater sensitivity than the other scores. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

Synchronization of mutually coupled chaotic systems

We report on the experimental observation of both basic frequency locking synchronization and chaos synchronization between two mutually coupled chaotic subsystems. We show that these two kinds of synchronization are two stages of interaction between coupled chaotic systems. in particular the chaos synchronization could be understood as a state of phase locking between coupled chaotic oscillations.

Embeddings of m-cycle systems and incomplete m-cycle systems: m<=14

In this paper we completely settle the embedding problem for m-cycle systems with m less than or equal to 14. We also solve the more general problem of finding m-cycle systems of K-v - K-u when m is an element of {4,6,7,8,10,12,14}.

From anatomy to angioscopy: 164 years of crocodilian cardiovascular research, recent advances, and speculations

This paper present: a synthesis of current research on the crocodilian cardiovascular system with a view to encourage discussion and debate about the intricacies of this unique system and to provide ideas and suggestions for future studies. Innovative experimental approaches combined with new technologies have helped to resolve the complex flow and pressure patterns observed during non-shunting conditions that predominate in resting instrumented animals and during pulmonary to systemic shunting, which has been observed to occur spontaneously and during diving. The mechanisms and structures that may induce and regulate shunting are presented and the functional significance of a pulmonary to systemic shunt is discussed. (C) 1997 Elsevier Science Inc.

Subclinic atherosclerosis and cardiovascular risk factors in HIV-infected children: PERI study

Objectives To compare carotid intima-media thickness (cIMT) of children and adolescents with and without HIV infection and to determine associations among independent socio-demographic, clinical or cardiovascular variables and cIMT in HIV-infected children and adolescents. Patients and methods This is a matched case-control study comparing 83 HIV-infected and 83 healthy children and adolescents. Clinical and laboratorial parameters, cIMT and echocardiogram were measured. Results The cIMT was higher in HIV-infected individuals (median 480 mu m; interquartile range 463-518 mu m) compared with controls (426 mu m; range 415-453 mu m, P < 0.001). In addition, the HIV-infected group showed higher levels of high-sensitive C-reactive protein (medians 1.0 mg/l vs. 0.4 mg/l, P < 0.001), glycated hemoglobin (6.1 +/- 0.9 vs. 5.7 +/- 0.8%, P= 0.028) and triglycerides (medians 0.9 vs. 0.8 mmol/l, P= 0.031). Finally, this group showed lower levels of total and high-density lipoprotein-cholesterol. After multivariate analysis, increased cIMT was positively associated with stavudine use [odds ratio (OR): 18.9, P=0.005], left atrial/aorta index (OR: 15.6, P=0.019), suprailiac skinfold (OR: 7.9, P=0.019), tachypnea (OR: 5.9, P=0.031), CD8 lymphocyte count (OR: 5.7, P=0.033) and CD4 T-lymphocyte count (OR: 5.5, P=0.025). cIMT increment was negatively associated with total cholesterol (OR: 0.2, P=0.025) and with CD8 zenith (OR: 0.1, P=0.007). Conclusion In this sample of children and adolescents, having HIV infection was associated with increased cIMT and elevated prevalence of cardiovascular risk factors. These findings suggest that this group should be included in cardiovascular prevention programs.

2m-cycle systems of K2m+1/C-m

For all m greater than or equal to 3 the edges of complete graph on 2m + 1 vertices can he partitioned into m 2m-cycles and an m-cycle.

Improving wheat simulation capabilities in Australia from a cropping systems perspective: water and nitrogen effects on spring wheat in a semi-arid environment

Systems approaches can help to evaluate and improve the agronomic and economic viability of nitrogen application in the frequently water-limited environments. This requires a sound understanding of crop physiological processes and well tested simulation models. Thus, this experiment on spring wheat aimed to better quantify water x nitrogen effects on wheat by deriving some key crop physiological parameters that have proven useful in simulating crop growth. For spring wheat grown in Northern Australia under four levels of nitrogen (0 to 360 kg N ha(-1)) and either entirely on stored soil moisture or under full irrigation, kernel yields ranged from 343 to 719 g m(-2). Yield increases were strongly associated with increases in kernel number (9150-19950 kernels m(-2)), indicating the sensitivity of this parameter to water and N availability. Total water extraction under a rain shelter was 240 mm with a maximum extraction depth of 1.5 m. A substantial amount of mineral nitrogen available deep in the profile (below 0.9 m) was taken up by the crop. This was the source of nitrogen uptake observed after anthesis. Under dry conditions this late uptake accounted for approximately 50% of total nitrogen uptake and resulted in high (>2%) kernel nitrogen percentages even when no nitrogen was applied,Anthesis LAI values under sub-optimal water supply were reduced by 63% and under sub-optimal nitrogen supply by 50%. Radiation use efficiency (RUE) based on total incident short-wave radiation was 1.34 g MJ(-1) and did not differ among treatments. The conservative nature of RUE was the result of the crop reducing leaf area rather than leaf nitrogen content (which would have affected photosynthetic activity) under these moderate levels of nitrogen limitation. The transpiration efficiency coefficient was also conservative and averaged 4.7 Pa in the dry treatments. Kernel nitrogen percentage varied from 2.08 to 2.42%. The study provides a data set and a basis to consider ways to improve simulation capabilities of water and nitrogen effects on spring wheat. (C) 1997 Elsevier Science B.V.

Improvement of Insulin Resistance and Reduction of Cardiovascular Risk Among Obese Patients with Type 2 Diabetes with the Duodenojejunal Bypass Liner

This study aims to evaluate the effectiveness of the duodenojejunal bypass liner (DJBL) in the improvement of insulin resistance and reduction of cardiovascular risk among morbidly obese patients with type 2 diabetes mellitus, using the triglyceride/high-density lipoprotein (HDL) cholesterol ratio, percentage of weight loss, and glycemic control. We used the TG/HDL ratio with a cutoff value of 3.5 to identify patients with insulin resistance. The value of the initial ratio was compared with the ratio obtained 6 months after implantation to evaluate whether an improvement in insulin resistance occurred. We also evaluated the improvement of glycated hemoglobin levels and the weight loss resulted from the use of the device and correlated that with the improvement of the TG/HDL ratio. All patients implanted with the device presented a statistically significant reduction of the HbA1c levels, with most patients (70.3%) obtaining diabetes control with HbA1c levels lower than 7% at the end of the study. All patients also presented a significant weight reduction, with an average loss of 12.6% of their initial weight. We observed an important improvement in insulin resistance and metabolic syndrome, with a significant reduction of the TG/HDL ratio from 5.75 to 4.36 (p < 0.001) and 42.6% of the patients presenting a TG/HDL ratio lower than 3.5 at the end of the study. The DJBL, when used for a period of 6 months, is effective in the control of diabetes, weight loss, improvement of insulin resistance, and decrease of cardiovascular risk among morbidly obese patients with type 2 diabetes mellitus.