Resveratrol treatment reduces cardiac progenitor cell dysfunction and prevents morpho-functional ventricular remodeling in type-1 diabetic rats

Emerging evidence suggests that both adult cardiac cell and the cardiac stem/progenitor cell (CSPC) compartments are involved in the patho-physiology of diabetic cardiomyopathy (DCM). We evaluated whether early administration of Resveratrol, a natural antioxidant polyphenolic compound, in addition to improving cardiomyocyte function, exerts a protective role on (i) the progenitor cell pool, and (ii) the myocardial environment and its impact on CSPCs, positively interfering with the onset of DCM phenotype. Adult Wistar rats (n?=?128) with streptozotocin-induced type-1 diabetes were either untreated (D group; n?=?54) or subjected to administration of trans-Resveratrol (i.p. injection: 2.5 mg/Kg/day; DR group; n?=?64). Twenty-five rats constituted the control group (C). After 1, 3 or 8 weeks of hyperglycemia, we evaluated cardiac hemodynamic performance, and cardiomyocyte contractile properties and intracellular calcium dynamics. Myocardial remodeling and tissue inflammation were also assessed by morphometry, immunohistochemistry and immunoblotting. Eventually, the impact of the diabetic "milieu" on CSPC turnover was analyzed in co-cultures of healthy CSPCs and cardiomyocytes isolated from D and DR diabetic hearts. In untreated animals, cardiac function was maintained during the first 3 weeks of hyperglycemia, although a definite ventricular remodeling was already present, mainly characterized by a marked loss of CSPCs and adult cardiac cells. Relevant signs of ventricular dysfunction appeared after 8 weeks of diabetes, and included: 1) a significant reduction in ±dP/dt in comparison with C group, 2) a prolongation of isovolumic contraction/relaxation times, 3) an impaired contraction of isolated cardiomyocytes associated with altered intracellular calcium dynamics. Resveratrol administration reduced atrial CSPC loss, succeeded in preserving the functional abilities of CSPCs and mature cardiac cells, improved cardiac environment by reducing inflammatory state and decreased unfavorable ventricular remodeling of the diabetic heart, leading to a marked recovery of ventricular function. These findings indicate that RSV can constitute an adjuvant therapeutic option in DCM prevention.     

Multiphoton Microscopy of Cleared Mouse Brain Expressing YFP

Multiphoton microscopy of intrinsic fluorescence and second harmonic generation (SHG) of whole mouse organs is made possible by optically clearing the organ before imaging.^1,2 However, for organs that contain fluorescent proteins such as GFP and YFP, optical clearing protocols that use methanol dehydration and clear using benzyl alcohol:benzyl benzoate (BABB) while unprotected from light³ do not preserve the fluorescent signal. The protocol presented here is a novel way in which to perform whole organ optical clearing on mouse brain while preserving the fluorescence signal of YFP expressed in neurons. Altering the optical clearing protocol such that the organ is dehydrated using an ethanol graded series has been found to reduce the damage to the fluorescent proteins and preserve their fluorescent signal for multiphoton imaging.⁴ Using an optimized method of optical clearing with ethanol-based dehydration and clearing by BABB while shielded from light, we show high-resolution multiphoton images of yellow fluorescent protein (YFP) expression in the neurons of a mouse brain more than 2 mm beneath the tissue surface.     

Complete genome sequence of the thermophilic sulfate-reducing ocean bacterium Thermodesulfatator indicus type strain (CIR29812(T))

Thermodesulfatator indicus Moussard et al. 2004 is a member of the Thermodesulfobacteriaceae, a family in the phylum Thermodesulfobacteria that is currently poorly characterized at the genome level. Members of this phylum are of interest because they represent a distinct, deep-branching, Gram-negative lineage. T. indicus is an anaerobic, thermophilic, chemolithoautotrophic sulfate reducer isolated from a deep-sea hydrothermal vent. Here we describe the features of this organism, together with the complete genome sequence, and annotation. The 2,322,224 bp long chromosome with its 2,233 protein-coding and 58 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.     

Searching for Euglossa cyanochlora Moure, 1996 (Hymenoptera: Apidae), one of the rarest bees in the world

Euglossa cyanochlora Moure, 1996 (Hymenoptera: Apidae: Euglossina) is known from only two specimens and is considered as one of the rarest bees. An intensive search for this species in its expected area of occurrence in eastern Brazil was carried out during three consecutive summers and involved over 1,000?h of active sampling in 50 sites distributed among 20 forest remnants. Almost 15,000 orchid bee males were attracted to scent baits and collected, but only 24 of them belonged to E. cyanochlora. Some degree of mitochondrial gene (COI, cytB, and 16S) variation was observed in this species. Although no intra-specific variation was identified at the 16S locus, three and six haplotypes were characterized at the COI and cytB genes, respectively. Combined data from field work and molecular analysis suggest that the species southernmost distribution limit is close to its type locality, near Parque Nacional do Monte Pascoal, in southern Bahia. The conservation status of E. cyanochlora is discussed and measures for its protection are here proposed.     

Genomic organisation of the <Emphasis Type="Italic">Mal d 1</Emphasis> gene cluster on linkage group 16 in apple

European populations exhibit progressive sensitisation to food allergens, and apples are one of the foods for which sensitisation is observed most frequently. Apple cultivars vary greatly in their allergenic characteristics, and a better understanding of the genetic basis of low allergenicity may therefore allow allergic individuals to increase their fruit intake. Mal d 1 is considered to be a major apple allergen, and this protein is encoded by the most complex allergen gene family. Not all Mal d 1 members are likely to be involved in allergenicity. Therefore, additional knowledge about the existence and characteristics of the different Mal d 1 genes is required. In the present study, we investigated the genomic organisation of the Mal d 1 gene cluster in linkage group 16 of apple through the sequencing of two bacterial artificial chromosome clones. The results provided new information on the composition of this family with respect to the number and orientation of functional and pseudogenes and their physical distances. The results were compared with the apple and peach genome sequences that have recently been made available. A broad analysis of the whole apple genome revealed the presence of new genes in this family, and a complete list of the observed Mal d 1 genes is supplied. Thus, this study provides an important contribution towards a better understanding of the genetics of the Mal d 1 family and establishes the basis for further research on allelic diversity among cultivars in relation to variation in allergenicity.     

Solution structure by nuclear magnetic resonance of the two lantibiotics 97518 and NAI‐107

Lantibiotics 97518 and NAI‐107, produced by the related genera Planomonospora and Microbispora respectively, are members of a family of nisin‐related compounds. They represent promising compounds to treat infections caused by multiresistant Gram‐positive pathogens. Despite their similar structure and a similar antibacterial spectrum, the two lantibiotics exhibit significant differences in their potency. To gain an insight into the structure–activity relationships, their conformational properties in solution are determined by NMR. After carrying out an NOE analysis of 2D ¹H NMR spectra, high‐resolution 3D structures are determined using molecular dynamics simulations. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd.     

Short sleep duration and obesity: mechanisms and future perspectives

A reduction of sleep time has become common over the last century, and growing evidence from both epidemiological and laboratory-based studies suggests sleep curtailment is a new risk factor for the development of obesity. On this basis, the present review examines the role of sleep curtailment in the metabolic and endocrine alterations, including decreased glucose tolerance and insulin sensitivity, increased evening concentrations of cortisol, increased levels of ghrelin, decreased levels of leptin and increased hunger and appetite. It will be discussed how sleep restriction may lead to increase in food intake and result in greater fatigue, which may favour decreased energy expenditure. Altogether, evidences point to a possible role of decreased sleep duration in the current epidemic of obesity and therefore present literature highlights the importance of getting enough good sleep for metabolic health. Many aspects still need to be clarified and intervention studies also need to be conducted. Copyright ? 2012 John Wiley & Sons, Ltd.     

High Spatial Resolution and Temporally Resolved T2 * Mapping of Normal Human Myocardium at 7.0 Tesla: An Ultrahigh Field Magnetic Resonance Feasibility Study

Myocardial tissue characterization using T₂ ^* relaxation mapping techniques is an emerging application of (pre)clinical cardiovascular magnetic resonance imaging. The increase in microscopic susceptibility at higher magnetic field strengths renders myocardial T₂ ^* mapping at ultrahigh magnetic fields conceptually appealing. This work demonstrates the feasibility of myocardial T₂ ^* imaging at 7.0 T and examines the applicability of temporally-resolved and high spatial resolution myocardial T₂ ^* mapping. In phantom experiments single cardiac phase and dynamic (CINE) gradient echo imaging techniques provided similar T₂ ^* maps. In vivo studies showed that the peak-to-peak B₀ difference following volume selective shimming was reduced to approximately 80 Hz for the four chamber view and mid-ventricular short axis view of the heart and to 65 Hz for the left ventricle. No severe susceptibility artifacts were detected in the septum and in the lateral wall for T₂ ^* weighting ranging from TE = 2.04 ms to TE = 10.2 ms. For TE >7 ms, a susceptibility weighting induced signal void was observed within the anterior and inferior myocardial segments. The longest T₂ ^* values were found for anterior (T₂ ^* = 14.0 ms), anteroseptal (T₂ ^* = 17.2 ms) and inferoseptal (T₂ ^* = 16.5 ms) myocardial segments. Shorter T₂ ^* values were observed for inferior (T₂ ^* = 10.6 ms) and inferolateral (T₂ ^* = 11.4 ms) segments. A significant difference (p = 0.002) in T₂ ^* values was observed between end-diastole and end-systole with T₂ ^* changes of up to approximately 27% over the cardiac cycle which were pronounced in the septum. To conclude, these results underscore the challenges of myocardial T₂ ^* mapping at 7.0 T but demonstrate that these issues can be offset by using tailored shimming techniques and dedicated acquisition schemes.