Blood pressure, body mass index and risk of cardiovascular disease in Chinese men and women

<p>Abstract</p> <p>Background</p> <p>It is still uncertain whether increased blood pressure (BP) has a stronger effect on the risk of cardiovascular disease (CVD) in lean persons than in obese persons. We tested it using a data set collected from a large cohort of Chinese adults.</p> <p>Methods</p> <p>Systolic and diastolic BP, body mass index (BMI) and other variables were measured in 169,871 Chinese men and women ≥ 40 years of age in 1991 using standard protocols. Follow-up evaluation was conducted in 1999-2000, with a response rate of 93.4%. Data were analyzed with Cox proportional hazards models.</p> <p>Results</p> <p>After adjusted for age, sex, cigarette smoking, alcohol consumption, high school education, physical inactivity, geographic region, and urbanization, we found that the effects of systolic or diastolic BP on risk of CVD generally increased with the increasing BMI levels (underweight, normal, overweight, and obese). For example, hazard ratios (HRs) and 95% confidence interval (CI) per 1- standard deviation (SD) increase in systolic BP within corresponding BMI levels were 1.27(1.21-1.33), 1.45(1.41-1.48), 1.52 (1.45-1.59) and 1.63 (1.51-1.76), respectively. Statistically significant interactions (P < 0.0001) were observed between systolic BP, diastolic BP and BMI in relation to CVD. In baseline hypertensive participants we found both obese men and women had higher risk of CVD than normal-weight persons. The multivariate-adjusted HRs(95%CI) were 1.23(1.03-1.47) and 1.20(1.02-1.40), respectively.</p> <p>Conclusion</p> <p>Our study suggests that the magnitude of the association between BP and CVD generally increase with increasing BMI. Hypertension should not be regarded as a less serious risk factor in obese than in lean or normal-weight persons in Chinese adults.</p

Preferential benefits of nifedipine GITS in systolic hypertension and in combination with RAS blockade: further analysis of the ‘ACTION' database in patients with angina

A retrospective analysis of the database from A Coronary Disease Trial Investigating Outcome with Nifedipine (ACTION) evaluated the effectiveness of nifedipine gastrointestinal therapeutic system (GITS) (i) in combination with renin angiotensin system (RAS) blockers and (ii) in patients with isolated systolic hypertension (ISH). Analysed on an intention-to-treat basis, treatment groups were compared by the log-rank test without adjustment for covariates and hazard ratios with 95% CIs were obtained using Cox proportional hazards models. Of 7665 randomized patients, 1732 patients were receiving RAS blockade at baseline, the addition of nifedipine GITS significantly reduced any cardiovascular (CV) event (−20% P<0.05), the composite of death, any CV event and revascularization (−16% P<0.05) and coronary angiography (−22% P<0.01). These benefits were achieved with relatively small differences in systolic (3.2 mm Hg) and diastolic blood pressure (BP) (2.3 mm Hg). In 2303 patients (30.0%) who had ISH at baseline (1145 nifedipine GITS and 1158 placebo), nifedipine significantly reduced the primary efficacy end point (−18% P<0.03), any CV event (−22% P<0.01) and new heart failure (−40% P<0.01). The benefits were associated with between-group differences in achieved BP of 4.7 and 3.3 mm Hg for systolic and diastolic BP, respectively. In summary, the lowest CV event rates were seen in those receiving (i) the combination of RAS blockade and nifedipine GITS and (ii) in those specifically treated for ISH

Why Can't Rodents Vomit? A Comparative Behavioral, Anatomical, and Physiological Study

The vomiting (emetic) reflex is documented in numerous mammalian species, including primates and carnivores, yet laboratory rats and mice appear to lack this response. It is unclear whether these rodents do not vomit because of anatomical constraints (e.g., a relatively long abdominal esophagus) or lack of key neural circuits. Moreover, it is unknown whether laboratory rodents are representative of Rodentia with regards to this reflex. Here we conducted behavioral testing of members of all three major groups of Rodentia; mouse-related (rat, mouse, vole, beaver), Ctenohystrica (guinea pig, nutria), and squirrel-related (mountain beaver) species. Prototypical emetic agents, apomorphine (sc), veratrine (sc), and copper sulfate (ig), failed to produce either retching or vomiting in these species (although other behavioral effects, e.g., locomotion, were noted). These rodents also had anatomical constraints, which could limit the efficiency of vomiting should it be attempted, including reduced muscularity of the diaphragm and stomach geometry that is not well structured for moving contents towards the esophagus compared to species that can vomit (cat, ferret, and musk shrew). Lastly, an in situ brainstem preparation was used to make sensitive measures of mouth, esophagus, and shoulder muscular movements, and phrenic nerve activity-key features of emetic episodes. Laboratory mice and rats failed to display any of the common coordinated actions of these indices after typical emetic stimulation (resiniferatoxin and vagal afferent stimulation) compared to musk shrews. Overall the results suggest that the inability to vomit is a general property of Rodentia and that an absent brainstem neurological component is the most likely cause. The implications of these findings for the utility of rodents as models in the area of emesis research are discussed. © 2013 Horn et al

Building connectomes using diffusion MRI: why, how and but

Why has diffusion MRI become a principal modality for mapping connectomes in vivo? How do different image acquisition parameters, fiber tracking algorithms and other methodological choices affect connectome estimation? What are the main factors that dictate the success and failure of connectome reconstruction? These are some of the key questions that we aim to address in this review. We provide an overview of the key methods that can be used to estimate the nodes and edges of macroscale connectomes, and we discuss open problems and inherent limitations. We argue that diffusion MRI-based connectome mapping methods are still in their infancy and caution against blind application of deep white matter tractography due to the challenges inherent to connectome reconstruction. We review a number of studies that provide evidence of useful microstructural and network properties that can be extracted in various independent and biologically-relevant contexts. Finally, we highlight some of the key deficiencies of current macroscale connectome mapping methodologies and motivate future developments

VARIATION OF THE FERRET SKULL (MUSTELA-PUTORIUS-FURO L) IN RELATION TO STEREOTAXIC LANDMARKS

The ferret skull was investigated to identify reliable extracranial landmarks for stereotaxy. The skulls of 56 ferrets of both sexes were measured in a stereotaxic apparatus. Neither body weight nor an index of skull length proved to be reliable predictors of intracranial location. Sutures fused too early in life for lambda and bregma to be useful as landmarks in adult ferrets. The position of extracranial features was used to predict the position of intracranial features. For rostral intracranial features, the supraorbital processes were found to be the best predictors. Although the occipital crest was not the best predictor for posterior structures, it was the most practical. Using these landmarks, the prediction of intracranial location could be improved by more than 30%. Sexual dimorphism was found for all features examined except those nearest the interaural line. Female skulls were significantly smaller than male skulls and had less prominent sagittal and occipital crests. Males showed a substantial variation in the structures surrounding the pituitary gland. Fitches were also found to differ from albinos in having a more marked development of the sagittal crest

White matter pathway asymmetry underlies functional lateralization.

Structural and functional asymmetry of the human brain has been well documented using techniques such as magnetic resonance imaging (MRI). However, asymmetry of underlying white matter connections is less well understood. We applied an MRI technique known as diffusion tensor tractography to reveal the morphology of the white matter in vivo by mapping directions of maximum water diffusion in brain tissue. White matter pathway asymmetry was investigated in a normalized image data set of 30 right-handed young healthy individuals. We identified, for the first time, a rightwardly asymmetric pathway connecting the posterior temporal lobe to the superior parietal lobule. This pathway may be related to auditory spatial attention and working memory for which there is evidence for a rightward laterality from functional imaging studies. Additional leftward asymmetries connecting the parietal and frontal lobes to the temporal lobe may be more closely related to laterality of language