Building muscle: molecular regulation of myogenesis.

The genesis of skeletal muscle during embryonic development and postnatal life serves as a paradigm for stem and progenitor cell maintenance, lineage specification, and terminal differentiation. An elaborate interplay of extrinsic and intrinsic regulatory mechanisms controls myogenesis at all stages of development. Many aspects of adult myogenesis resemble or reiterate embryonic morphogenetic episodes, and related signaling mechanisms control the genetic networks that determine cell fate during these processes.

Comparison of maternity experiences of Canadian-born and recent and non-recent immigrant women: findings from the Canadian Maternity Experiences Survey.

Objective: To compare the maternity experiences of immigrant women (recent, ≤ 5 years in Canada; non-recent > 5 years) with those of Canadian-born women.

Methods: This study was based on data from the Canadian Maternity Experiences Survey of the Public Health Agency of Canada. A stratified random sample of 6421 women was drawn from a sampling frame based on the 2006 Canadian Census of Population.

Incidence, risk factors, and associated complications of eclampsia.

Objective: To estimate trends in incidence and identify risk factors and maternal and neonatal consequences of eclampsia in Canada.

Methods: We conducted a population-based cohort study of all women and their newborns (N=1,910,729) delivered in the hospital in Canada (excluding Quebec) from 2003 to 2009. The data were obtained from the Canadian Institute for Health Information.

Reactive oxygen species and endothelial function--role of nitric oxide synthase uncoupling and Nox family nicotinamide adenine dinucleotide phosphate oxidases.

The healthy endothelium prevents platelet aggregation and leucocyte adhesion, controls permeability to plasma components and maintains vascular integrity. Damage to the endothelium promotes endothelial dysfunction characterized by: altered endothelium-mediated vasodilation, increased vascular reactivity, platelet aggregation, thrombus formation, increased permeability, leucocyte adhesion and monocyte migration. Molecular processes contributing to these phenomena include increased expression of adhesion molecules, synthesis of pro-inflammatory and pro-thrombotic factors and increased endothelin-1 secretion.

Ablation of LMO4 in glutamatergic neurons impairs leptin control of fat metabolism.

The LIM domain only 4 (LMO4) protein is expressed in the hypothalamus, but its function there is not known. Using mice with LMO4 ablated in postnatal glutamatergic neurons, including most neurons of the paraventricular (PVN) and ventromedial (VMH) hypothalamic nuclei where LMO4 is expressed, we asked whether LMO4 is required for metabolic homeostasis. LMO4 mutant mice exhibited early onset adiposity.

Precision of healthcare systematic review searches in a cross-sectional sample.

Background: In systematic reviews, search precision is generally traded off against the desire to retrieve all relevant studies; however, there is no published evidence on typical precision values. The objective of this study is to establish typical values for the precision of systematic review searches in healthcare.

Methods: From an existing cross-sectional sample of 300 MEDLINE-indexed systematic reviews, those that reported the flow of bibliographic records through the review process (n = 109) were examined.

Applying psychological theories to evidence-based clinical practice: identifying factors predictive of lumbar spine x-ray for low back pain in UK primary care practice.

Background: Psychological models predict behaviour in a wide range of settings. The aim of this study was to explore the usefulness of a range of psychological models to predict the health professional behaviour 'referral for lumbar spine x-ray in patients presenting with low back pain' by UK primary care physicians.

Methods: Psychological measures were collected by postal questionnaire survey from a random sample of primary care physicians in Scotland and north England.

NOX isoforms and reactive oxygen species in vascular health.

Reactive oxygen species (ROS) are important mediators of cell growth, adhesion, differentiation, migration, senescence, and apoptosis. ROS play an important physiological role in regulating vascular tone and can also contribute to pathological mechanisms related to endothelial dysfunction, vascular reactivity, arterial remodeling, and vascular inflammation. The major source of ROS generated in the cardiovascular system is the NADPH oxidase (NOX) family of enzymes, of which seven members have been characterized.

Differential regulation of Nox1, Nox2 and Nox4 in vascular smooth muscle cells from WKY and SHR.

The functional significance and regulation of NAD(P)H oxidase (Nox) isoforms by angiotensin II (Ang II) and endothelin-1 (ET-1) in vascular smooth muscle cells (VSMCs) from normotensive Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR) was studied. Expression of Nox1, Nox2, and Nox4 (gene and protein) and NAD(P)H oxidase activity were increased in SHR. Basal NAD(P)H oxidase activity was blocked by GKT136901 (Nox1/4 inhibitor) and by Nox1 siRNA in WKY cells and by siNOX1 and siNOX2 in SHR.

Targeting tumor vasculature with an oncolytic virus.

Oncolytic viruses (OVs) have been engineered or selected for cancer cell-specific infection however, we have found that following intravenous administration of vesicular stomatitis virus (VSV), tumor cell killing rapidly extends far beyond the initial sites of infection. We show here for the first time that VSV directly infects and destroys tumor vasculature in vivo but leaves normal vasculature intact. Three-dimensional (3D) reconstruction of infected tumors revealed that the majority of the tumor mass lacks significant blood flow in contrast to uninfected tumors, which exhibit relatively uniform perfusion.

The risk of dying on days of higher air pollution among the socially disadvantaged elderly.

Rationale: The estimated mortality rate associated with ambient air pollution based on general population studies may not be applicable to certain subgroups.

Objective: The objective of the present study was to determine the influence of age, education, employment status and income on the risk of mortality associated with ambient air pollution.

Methods: Daily time-series analyses tested the association between daily air pollution and daily mortality in seven Chilean urban centers during the period January 1997-December 2007.

A comparative examination of tuberculosis immigration medical screening programs from selected countries with high immigration and low tuberculosis incidence rates.

Background: Tuberculosis (TB) in migrants is an ongoing challenge in several low TB incidence countries since a large proportion of TB in these countries occurs in migrants from high incidence countries. To meet these challenges, several countries utilize TB screening programs. The programs attempt to identify and treat those with active and/or infectious stages of the disease.

Reactive oxygen species and vascular biology: implications in human hypertension.

Increased vascular production of reactive oxygen species (ROS; termed oxidative stress) has been implicated in various chronic diseases, including hypertension. Oxidative stress is both a cause and a consequence of hypertension. Although oxidative injury may not be the sole etiology, it amplifies blood pressure elevation in the presence of other pro-hypertensive factors.

Hand assisted laparoscopic surgery versus conventional laparoscopy for colorectal surgery.

Background: Laparoscopic surgery for colon disease has been shown to have advantages over the open approach in the perioperative period in terms of shorter hospital stay, decreased analgesic use and a more rapid return of bowel function but provides these benefits at the expense of increased technical difficulty and operative time. Hand assisted surgery which a is a hybrid of open surgery and laparoscopic surgery may offer patients the perioperative advantages of minimally invasive surgery without the technical difficulty and increased operative time associated with the conventional laparoscopic approach. This review compares the benefits and harms of laparoscopic and hand assisted laparoscopic surgery for colon disease.

Extrinsic regulation of satellite cell specification.

Cellular commitment during vertebrate embryogenesis is controlled by an interplay of intrinsic regulators and morphogenetic signals. These mechanisms recruit a subset of cells in the developing organism to become the ancestors of skeletal muscle. Signals that control progression through the myogenic lineage converge on a battery of hierarchically organized transcription factors which modulate the cells to either remain in a primitive state or allow their commitment and differentiation into skeletal muscle fibers.

A threshold regression model for recurrent exacerbations in chronic obstructive pulmonary disease.

Objective: Respiratory exacerbations are a major source of morbidity in patients with chronic obstructive pulmonary disease (COPD). In this article, we model COPD health status as a formal stochastic process. A successful model will provide a suitable statistical structure for analysis of the effects of medical interventions on a patient's health status, and, possibly, offer new insights into the underlying disease process.

Oxidative status of muscle is determined by p107 regulation of PGC-1alpha.

Mice lacking p107 exhibit a white adipose deficiency yet do not manifest the metabolic changes typical for lipodystrophy, and instead exhibit low levels of serum triglycerides and a normal liver phenotype. When fed a high fat diet, p107-null mice still did not accumulate fat in the liver, and display markedly elevated energy expenditures together with an increased energy preference for lipids. Skeletal muscle was therefore examined, as this is normally the major tissue involved in whole body lipid metabolism.

Strengthening the International Health Regulations: lessons from the H1N1 pandemic.

The International Health Regulations (2005) [IHR(2005)] represent a potentially revolutionary change in global health governance. The use of the regulations by the World Health Organization (WHO) to respond to the outbreak of pandemic influenza A 2009-H1N1 highlights the importance of the regulations to protecting global health security. As the 2009-H1N1 pandemic illustrated, the IHR(2005) have provided a more robust framework for responding to public health emergencies of international concern (PHEICs), through requiring reporting of serious disease events, strengthening how countries and WHO communicate concerning health threats, empowering the WHO Director-General to declare the existence of PHEICs and to issue temporary recommendations for responding to them, and requiring countries not to implement measures that unnecessarily restrict trade and travel or infringe on human rights.

The risk of adverse pregnancy outcomes is increased in preeclamptic women who smoke compared with nonpreeclamptic women who do not smoke.

Objective: Maternal smoking and preeclampsia independently increase the risk of adverse pregnancy outcomes; however, smoking decreases the risk of preeclampsia. We sought to estimate the risk of adverse pregnancy outcomes among preeclamptic women who smoke and hypothesized that this risk would be increased, compared with nonpreeclamptic women who smoke or preeclamptic women who do not smoke.

Study Design: With the use of the Niday Perinatal Database and multiple logistic regressions, we estimated the risk of adverse pregnancy outcomes in nonpreeclamptic women who smoke, preeclamptic women who do not smoke, and preeclamptic women who smoke in relation to nonpreeclamptic women who do not smoke.

Allergic and hypersensitivity reactions in the intensive care unit.

Hypersensitivity reactions are defined as immunologically based adverse reactions to chemicals or medicinal agents. These reactions are common in the intensive care unit and can present as a simple, mildly symptomatic rash or as life-threatening anaphylactic reactions. Hypersensitivity reactions have traditionally been classified as types I to IV reactions based on the underlying immune mechanisms, although the clinical relevance of the classification is unclear, and new subtypes to this system have been recently proposed.

Air pollution and hospitalization for epilepsy in Chile.

Objective: To determine the association between gaseous and fine particulate air pollution (PM(2.5)) and epilepsy in a general population sample.

Method: A daily time-series analyses tested the association between daily hospitalization for epilepsy in seven Chilean urban centers during the period 2001 and 2005.

Oxidative stress and hypertension: current concepts.

Hypertension is a major contributor to the development of renal failure, cardiovascular disease, and stroke. These pathologies are associated with vascular functional and structural changes including endothelial dysfunction, altered contractility, and vascular remodeling. Central to these phenomena is oxidative stress.

Multi analyte profiling and variability of inflammatory markers in blood and induced sputum in patients with stable COPD.

Background: We analyzed serial concentrations of multiple inflammatory mediators from serum and induced sputum obtained from patients with stable COPD and controls. The objective was to determine which proteins could be used as reliable biomarkers to assess COPD disease state and severity.

Methods: Forty-two subjects; 21 with stable COPD and 21 controls, were studied every 2 weeks over a 6-week period.