Microarray analysis of expression of cell death-associated genes in rat spinal cord cells exposed to cyclic tensile stresses in vitro

<p>Abstract</p> <p>Background</p> <p>The application of mechanical insults to the spinal cord results in profound cellular and molecular changes, including the induction of neuronal cell death and altered gene expression profiles. Previous studies have described alterations in gene expression following spinal cord injury, but the specificity of this response to mechanical stimuli is difficult to investigate in vivo. Therefore, we have investigated the effect of cyclic tensile stresses on cultured spinal cord cells from E15 Sprague-Dawley rats, using the FX3000^®Flexercell Strain Unit. We examined cell morphology and viability over a 72 hour time course. Microarray analysis of gene expression was performed using the Affymetrix GeneChip System^®, where categorization of identified genes was performed using the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) systems. Changes in expression of 12 genes were validated with quantitative real-time reverse transcription polymerase chain reaction (RT-PCR).</p> <p>Results</p> <p>The application of cyclic tensile stress reduced the viability of cultured spinal cord cells significantly in a dose- and time-dependent manner. Increasing either the strain or the strain rate independently was associated with significant decreases in spinal cord cell survival. There was no clear evidence of additive effects of strain level with strain rate. GO analysis identified 44 candidate genes which were significantly related to "apoptosis" and 17 genes related to "response to stimulus". KEGG analysis identified changes in the expression levels of 12 genes of the mitogen-activated protein kinase (MAPK) signaling pathway, which were confirmed to be upregulated by RT-PCR analysis.</p> <p>Conclusions</p> <p>We have demonstrated that spinal cord cells undergo cell death in response to cyclic tensile stresses, which were dose- and time-dependent. In addition, we have identified the up regulation of various genes, in particular of the MAPK pathway, which may be involved in this cellular response. These data may prove useful, as the accurate knowledge of neuronal gene expression in response to cyclic tensile stress will help in the development of molecular-based therapies for spinal cord injury.</p

2007 Focused Update of the ACC/AHA/SCAI 2005 Guideline Update for Percutaneous Coronary Intervention. A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines

"Selected late-breaking clinical trials presented at the 2005 and 2006 annual scientific meetings of the ACC, AHA, and European Society of Cardiology, as well as selected other data, were reviewed by the standing guideline writing committee along with the parent Task Force and other experts to identify those trials and other key data that might impact guideline recommendations. On the basis of the criteria/considerations noted above, recent trial data and other clinical information were considered important enough to prompt a focused update of the ACC/AHA/SCAI 2005 Guideline Update for Percutaneous Coronary Intervention (3–13). To provide clinicians with a comprehensive set of data, whenever possible, the exact event rates in various treatment arms of clinical trials are presented to permit calculation of the absolute risk difference (ARD) and number needed to treat (NNT) or harm (NNH); the relative treatment effects are described either as odds ratio (OR), relative risk (RR), or hazard ratio (HR), depending on the format in the original publication. Consult the full-text version or executive summary of the ACC/AHA/SCAI 2005 Guideline Update for Percutaneous Coronary Intervention for policy on clinical areas not covered by the focused update (13a). Individual recommendations updated in this focused update will be incorporated into future revisions and/or updates of the full-text guidelines.

Enhanced diagnostic immunofluorescence using biopsies transported in saline

BACKGROUND: The demonstration of tissue-bound immunoreactants by direct immunofluorescence microscopy (DIF) is a valuable parameter in the diagnosis of various autoimmune and immunecomplex-mediated skin diseases. For preservation of tissue-bound immunoreactants, biopsies are usually fresh-frozen in liquid nitrogen or transported in Michel's fixative. But even optimally preserved tissue specimens are no guarantee for the correct diagnosis by DIF, especially when weak to moderate IgG fluorescence of the epidermal basement membrane zone is involved. In such cases false negative results are easily obtained due to the relatively high dermal "background" fluorescence produced by polyclonal anti-human IgG fluorescein conjugates. METHODS: In the present study we have compared the use of normal saline (0.9% NaCl) with liquid nitrogen and Michel's fixative as transport medium for skin biopsies. From 25 patients with an autoimmune skin disease (pemphigus, pemphigoid, lupus erythematosus and vasculitis) four matched skin biopsies were obtained and transported in either saline for 24 and 48 hours, liquid nitrogen, or Michel's fixative for 48 hours. RESULTS: Direct IF microscopy showed significant reduction of background fluorescence (p < 0.01) and relatively enhanced desired specific (IgG, IgA) staining in biopsies transported in saline. A conclusive or tentative IF diagnosis was reached in 92% after 24 h saline, 83% after 48 h saline, 68% after freezing in liquid nitrogen, and 62% after 48 h Michel's medium (n = 25). CONCLUSIONS: We conclude that transporting biopsies without freezing in normal saline for 24 hours is an adequate and attractive method for routine IF diagnosis in autoimmune and immune complex-mediated dermatoses. The superior results with saline incubation are explained by washing away of IgG background in dermis and epidermis

Prevalence of the metabolic syndrome among children from six cities of China

<p>Abstract</p> <p>Background</p> <p>Metabolic syndrome (MetS) in childhood can increase the risk of cardiovascular disease, diabetes mellitus and dyslipidemia in adulthood, which is of increasing concern in transitional and advanced economies. The aim of the current study was to explore the prevalence of MetS among children from six cities of China.</p> <p>Methods</p> <p>A total of 8,764 children (4,495 boys, 4,269 girls) aged 7-11 years were randomly selected from 6 cities of China. MetS was mainly defined by the criteria proposed by International Diabetes Federation (IDF).</p> <p>Results</p> <p>The overall prevalence of MetS for children older than 10 years was 0.8% by IDF definition. Obese children had significantly higher MetS prevalence compared with their counterparts with overweight (6.6% vs. 0.9%, <it>p </it>< 0.01) and normal weight (6.6% vs. 0.05%, <it>p </it>< 0.01). The prevalence of abdominal obesity, high triglycerides, low high density lipoprotein cholesterol, hypertension and high glucose among obese children was 93.4%, 16.5%, 14.3%, 7.3% and 4.0%, respectively, which significantly higher than those among overweight children (37.0%, 6.1%, 10.0%, 4.2%, and 3.3%, respectively) and among normal weight children (1.2%, 3.3%, 4.0%, 1.7% and 2.5%, respectively). The proportion of children with at least one, two, and three items of the metabolic abnormalities were 25.0%, 5.4% and 0.9%, respectively. Metabolic abnormalities were also present in children under 10 years of age.</p> <p>Conclusions</p> <p>The early onset of MetS among children and relatively high proportions of children with at least one or two metabolic abnormalities in cities of China can increase the risk of developing MetS. It implies the necessity to take effective actions to control and prevent the rapid development of obesity among children in developing countries, especial those undergoing transition to a Western lifestyle.</p

Kepler Planet-Detection Mission: Introduction and First Results

The Kepler mission was designed to determine the frequency of Earth-sized planets in and near the habitable zone of Sun-like stars. The habitable zone is the region where planetary temperatures are suitable for water to exist on a planet’s surface. During the first 6 weeks of observations, Kepler monitored 156,000 stars, and five new exoplanets with sizes between 0.37 and 1.6 Jupiter radii and orbital periods from 3.2 to 4.9 days were discovered. The density of the Neptune-sized Kepler-4b is similar to that of Neptune and GJ 436b, even though the irradiation level is 800,000 times higher. Kepler-7b is one of the lowest-density planets (~0.17 gram per cubic centimeter) yet detected. Kepler-5b, -6b, and -8b confirm the existence of planets with densities lower than those predicted for gas giant planets

Ice structures, patterns, and processes: A view across the ice-fields

We look ahead from the frontiers of research on ice dynamics in its broadest sense; on the structures of ice, the patterns or morphologies it may assume, and the physical and chemical processes in which it is involved. We highlight open questions in the various fields of ice research in nature; ranging from terrestrial and oceanic ice on Earth, to ice in the atmosphere, to ice on other solar system bodies and in interstellar space