Analysis of cardiac signals using spatial filling index and time-frequency domain

Background  

Analysis of heart rate variation (HRV) has become a popular noninvasive tool for assessing the activities of the autonomic nervous system (ANS). HRV analysis is based on the concept that fast fluctuations may specifically reflect changes of sympathetic and vagal activity. It shows that the structure generating the signal is not simply linear, but also involves nonlinear contributions. These signals are essentially non-stationary; may contain indicators of current disease, or even warnings about impending diseases. The indicators may be present at all times or may occur at random in the time scale. However, to study and pinpoint abnormalities in voluminous data collected over several hours is strenuous and time consuming.     

Diabetogenic diet-induced insulin resistance associates with lipid droplet proteins and adipose tissue secretome,but not with sexual dimorphic adipose tissue fat accumulation in Wistar rats

The role of sexual dimorphic adipose tissue fat accumulation in the development of insulin resistance is well known. However, whether vitamin A status and/or its metabolic pathway display any sex- or depot (visceral/subcutaneous)-specific pattern and have a role in sexual dimorphic adipose tissue development and insulin resistance are not completely understood. Therefore, to assess this, 5 weeks old Wistar male and female rats of eight from each sex were provided either control or diabetogenic (high fat, high sucrose) diet for 26 weeks. At the end, consumption of diabetogenic diet increased the visceral fat depots (p < 0.001) in the males and subcutaneous depot (p < 0.05) in the female rats, compared to their sex-matched controls. On the other hand, it caused adipocyte hypertrophy (p < 0.05) of visceral depot (retroperitoneal) in the females and subcutaneous depot of the male rats. Although vitamin A levels displayed sex- and depot-specific increase due to the consumption of diabetogenic diet, the expression of most of its metabolic pathway genes in adipose depots remained unaltered. However, the mRNA levels of some of lipid droplet proteins (perilipins) and adipose tissue secretory proteins (interleukins, lipocalin-2) did display sexual dimorphism. Nonetheless, the long-term feeding of diabetogenic diet impaired the insulin sensitivity, thus affected glucose clearance rate and muscle glucose-uptake in both the sexes of rats. In conclusion, the chronic consumption of diabetogenic diet caused insulin resistance in the male and female rats, but did not corroborate with sexual dimorphic adipose tissue fat accumulation or its vitamin A status.     

Symmetric cyanine dyes for detecting nucleic acids

A novel approach to the design of sensitive fluorescent probes for nucleic acids detection is proposed. Suitable modifications of tri- and pentamethine cyanine dyes in the polymethine chain and/or in the heterocyclic residues can result in a significant decrease in unbound dye fluorescence intensity and an increase in dye emission intensity in the presence of DNA compared to the unsubstituted dye. The sharp enhancement in the fluorescence intensity upon dye interaction with double-stranded DNA permits the application of the modified tri- and pentamethine dyes as fluorescent probes in double-stranded DNA detection in homogeneous assays.     

Novel Synthesis of a New Class of Polynuclear Pyridinethione Nucleosides

Abstract

A novel synthesis of a new class of polynuclear pyridinethione glycosides utilizing the reactions of phenanthridine analogues and α-bromoglucose or α-bromogalactose tetraacetate as starting components is described.     

Extracellular matrix metalloproteinase inducer (EMMPRIN/CD147) as a novel regulator of myogenic cell differentiation

Matrix metalloproteinases (MMPs) are thought to play an important role in skeletal muscle cell growth and differentiation. In view of the MMP inducing function of EMMPRIN/CD147, its role in myogenic cell differentiation was investigated. EMMPRIN level increased during differentiation of both rat primary myoblasts derived from satellite cells and mouse C2.7 myogenic cells and was associated with an alteration in its molecular forms. In parallel, expression of pro‐MMP‐9 gradually decreased and that of pro‐MMP‐2 and active MMP‐2 increased. While small interfering RNA (siRNA) inhibition of EMMPRIN expression accelerated cell differentiation, exogenously added recombinant EMMPRIN inhibited differentiation by an MMP‐mediated mechanism, as the MMP inhibitor marimastat abrogated EMMPRIN's effect. Our results further suggest that EMMPRIN regulates differentiation through an MMP activation of transforming growth factor beta (TGFβ), a known inhibitor of myoblast's differentiation, as the increased activation and signaling of TGFβ by EMMPRIN was attenuated in the presence of marimastat. EMMPRIN inhibition may thus represent a novel strategy in the treatment of muscular degenerative disorders. J. Cell. Physiol. 226: 141–149, 2010. © 2010 Wiley‐Liss, Inc.     

Thymoquinone suppression of the human hepatocellular carcinoma cell growth involves inhibition of IL-8 expression,elevated levels of TRAIL receptors,oxidative stress and apoptosis

Sod2 is the major salt tolerance plasma membrane protein of Schizosaccharomyces pombe. It functions to remove excess intracellular sodium (or lithium) in exchange for protons. We investigated the role of cysteine residues and created a cysteine-free Sod2 protein. Each cysteine residue of the ten present was individually mutated to serine and the different proteins expressed and characterized in S. pombe. Western blotting revealed that all the individual mutant proteins were expressed. We examined the ability of the mutant proteins to confer salt tolerance to S. pombe with the endogenous Sod2 protein deleted. Only proteins with C26S and C374S mutations were partially reduced in their ability to confer salt tolerance. Additionally, they showed a change in conformation in comparison to the wild-type protein, indicated by differential sensitivity to trypsin. Deletion of all the cysteine residues of Sod2 resulted in a functional protein that was expressed in S. pombe at levels similar to the wild type and also conferred salt tolerance. The conformation of the cysteine-free Sod2 protein was not altered relative to the wild-type protein. We examined the accessibility of amino acids of the cysteineless protein present on putative extracellular loop 2. A cysteine placed at position Ala119 was accessible to externally applied [2-(trimethylammonium)ethyl] methane thiosulfonate bromide. The results demonstrate that cysteines in the Sod2 protein can be changed to serine residues resulting in an expressed, functional protein. The utility of the cysteine-free Sod2 protein for determination of topology and amino acid accessibility is demonstrated.     

Gene expression profiling of endometrium versus bone marrow-derived mesenchymal stem cells: upregulation of cytokine genes

Postulated Stem/progenitor cells involved in endometrium regeneration are epithelial, mesenchymal, and endothelial. Bone marrow (BM) has been implicated in endometrial stem cells. We aimed at studying gene expression profiling of endometrial mesenchymal stem cells compared to BM MSCS to better understand their nature and functional phenotype. Endometrial tissues were obtained from premenopausal hysterectomies (n = 3), minced and enzymatically digested as well as Normal BM aspirates (n=3). Immunophenotyping, differentiation to mesoderm, and proliferation were studied. The expression profile of 84 genes relevant to mesenchymal stem cells was performed. Fold change calculations were determined with SA Biosciences data analysis software. VEGF, G-CSF, and GM-CSF in cultures supernatants of MSCs were assayed by Luminex immunoassay. Endo MSCs possess properties similar to BM MSCs. Cumulative population doubling was significantly higher in Endo MSCs compared to BM MSCs (p < 0.001). 52 core genes were shared between both generated MSCs including stemness, self-renewal, members of the Notch, TGFB, FGF, and WNT.16 downregulated genes (VCAM, IGF1)and 16 upregulated in Endo MSCs compared to BM (p < 0.05 → fourfolds). They included mostly cytokine and growth factor genes G-CSF, GM-CSF, VWF, IL1b, GDF15, and KDR. VEGF and G-CSF levels were higher in Endo MSCs supernatants (p < 0.0001). Cells sharing MSC and endothelial cell characteristics could be isolated from the human endometrium. Endo MSCs share a core genetic profile with BM MSCs including stemness. They show upregulation of genes involved in vasculogenesis, angiogenesis, cell adhesion, growth proliferation, migration, and differentiation of endothelial cells, all contributing to endometrial function.     

Genotype Profile of Leishmania major Strains Isolated from Tunisian Rodent Reservoir Hosts Revealed by Multilocus Microsatellite Typing

Zoonotic cutaneous leishmaniasis (ZCL) caused by Leishmania (L.) major parasites represents a major health problem with a large spectrum of clinical manifestations. Psammomys (P.) obesus and Meriones (M.) shawi represent the most important host reservoirs of these parasites in Tunisia. We already reported that infection prevalence is different between these two rodent species. We aimed in this work to evaluate the importance of genetic diversity in L. major parasites isolated from different proven and suspected reservoirs for ZCL. Using the multilocus microsatellites typing (MLMT), we analyzed the genetic diversity among strains isolated from (i) P. obesus (n = 31), (ii) M. shawi (n = 8) and (iii) Mustela nivalis (n = 1), captured in Sidi Bouzid, an endemic region for ZCL located in the Center of Tunisia. Studied strains present a new homogeneous genotype profile so far as all tested markers and showed no polymorphism regardless of the parasite host-reservoir origin. This lack of genetic diversity among these L. major isolates is the first genetic information on strains isolated from Leishmania reservoirs hosts in Tunisia. This result indicates that rodent hosts are unlikely to exert a selective pressure on parasites and stresses on the similarity of geographic and ecological features in this study area. Overall, these results increase our knowledge among rodent reservoir hosts and L. major parasites interaction.