Comparison of human axillary odour profiles obtained by gas chromatography/mass spectrometry and skin microbial profiles obtained by denaturing gradient gel electrophoresis using multivariate pattern recognition

Several studies have shown that microbial action is responsible for many compounds responsible for human odour. In this paper, we compare the pattern of microbial profiles and that of chemical profiles of human axillary odour by using multivariate pattern matching techniques. Approximately 200 subjects from Carinthia, Austria, participated in the study. The microbial profiles were represented by denaturing gradient gel electrophoresis (DGGE) analysis and the axillary odour profiles were determined in the sweat samples collected by a stir-bar sampling device and analysed by gas chromatography/mass spectrometry (GC/MS). Both qualitative and quantitative distance metrics were used to construct dissimilarity matrices between samples which were then used to represent the patterns of these two types of profiles. The distance matrices were then compared by using the Mantel test and the Procrustean test. The results show that on the overall dataset there is no strong correlation between microbial and chemical profiles. When the data are split into family groups, correlations vary according to family with a range of estimated p values from 0.00 to 0.90 that the null hypothesis (no correlation) holds. When 32 subjects who followed four basic rules of behaviour were selected, the estimated p-values are 0.00 using qualitative and <0.01 using quantitative distance metrics, suggesting excellent evidence that there is a connection between the microbial and chemical signature.     

Multiple Roles of the Extracellular Vestibule Amino Acid Residues in the Function of the Rat P2X4 Receptor

The binding of ATP to trimeric P2X receptors (P2XR) causes an enlargement of the receptor extracellular vestibule, leading to opening of the cation-selective transmembrane pore, but specific roles of vestibule amino acid residues in receptor activation have not been evaluated systematically. In this study, alanine or cysteine scanning mutagenesis of V47–V61 and F324–N338 sequences of rat P2X4R revealed that V49, Y54, Q55, F324, and G325 mutants were poorly responsive to ATP and trafficking was only affected by the V49 mutation. The Y54F and Y54W mutations, but not the Y54L mutation, rescued receptor function, suggesting that an aromatic residue is important at this position. Furthermore, the Y54A and Y54C receptor function was partially rescued by ivermectin, a positive allosteric modulator of P2X4R, suggesting a rightward shift in the potency of ATP to activate P2X4R. The Q55T, Q55N, Q55E, and Q55K mutations resulted in non-responsive receptors and only the Q55E mutant was ivermectin-sensitive. The F324L, F324Y, and F324W mutations also rescued receptor function partially or completely, ivermectin action on channel gating was preserved in all mutants, and changes in ATP responsiveness correlated with the hydrophobicity and side chain volume of the substituent. The G325P mutant had a normal response to ATP, suggesting that G325 is a flexible hinge. A topological analysis revealed that the G325 and F324 residues disrupt a β-sheet upon ATP binding. These results indicate multiple roles of the extracellular vestibule amino acid residues in the P2X4R function: the V49 residue is important for receptor trafficking to plasma membrane, the Y54 and Q55 residues play a critical role in channel gating and the F324 and G325 residues are critical for vestibule widening.     

Disulfiram moderately restores impaired hepatic redox status of rats subchronically exposed to cadmium

Examination of cadmium (Cd) toxicity and disulfiram (DSF) effect on liver was focused on oxidative stress (OS), bioelements status, morphological and functional changes. Male Wistar rats were intraperitoneally treated with 1?mg CdCl₂/kg BW/day; orally with 178.5?mg DSF/kg BW/day for 1, 3, 10 and 21 days; and co-exposed from 22nd to 42nd day. The co-exposure nearly restored previously suppressed total superoxide dismutase (SOD), catalase (CAT) and increased glutathione peroxidase (GPx) activities; increased previously reduced glutathione reductase (GR) and total glutathione-S-transferase (GST) activities; reduced previously increased superoxide anion radical (O₂^·?) and malondialdehyde (MDA) levels; increased zinc (Zn) and iron (Fe), and decreased copper (Cu) (yet above control value), while magnesium (Mg) was not affected; and decreased serum alanine aminotransferases (ALT) levels. Histopathological examination showed signs of inflammation process as previously demonstrated by exposure to Cd. Overall, we ascertained partial liver redox status improvement, compared with the formerly Cd-induced impact.     

Rye SCAR markers for male fertility restoration in the P cytoplasm are also applicable to marker-assisted selection in the C cytoplasm

The study aimed at testing the usefulness of recently developed SCAR markers on rye (Secale cereale L.) chromosome 4R in hybrid breeding based on the C source of male sterility-inducing cytoplasm. Of 10 markers studied, 4 revealed polymorphisms between 2 inbred lines (544cms-C and Ot0-20) crossed to develop F2 and BC1 mapping populations. Analyses performed on 94 F2 and 93 BC1 plants allowed to extend a formerly constructed genetic map of chromosome arm 4RL. Three SCAR markers (SCP14M55, SCP15M55 and SCP16M58) were mapped in the vicinity of gene Rfc1, which restores male fertility in the C cytoplasm. The 3 tested SCAR markers proved to be effective in marker-assisted selection (MAS) for male fertility/sterility.     

Microcalorimetric investigation of the interactions in the ternary complex calmodulin-calcium-melittin

Flow microcalorimetric titrations of calmodulin with melittin at 25 degrees C revealed that the formation of the high-affinity one-to-one complex in the presence of Ca2+ (Comte, M., Maulet, Y., and Cox, J. A. (1983) Biochem, J. 209, 269-272) is entirely entropy driven (delta H0 = 30.3 kJ X mol-1; delta S0 = 275 J X K-1 X mol-1). Neither the proton nor the Mg2+ concentrations have any significant effect on the strength of the complex. In the absence of Ca2+, a nonspecific calmodulin-(melittin)n complex is formed; the latter is predominantly entropy driven, accompanied by a significant uptake of protons and fully antagonized by Mg2+. Enthalpy titrations of metal-free calmodulin with Ca2+ in the presence of an equimolar amount of melittin were carried out at pH 7.0 in two buffers of different protonation enthalpy. The enthalpy and proton release profiles indicate that: protons, absorbed by the nonspecific calmodulin-melittin complex, are released upon binding of the first Ca2+; Ca2+ binding to the high-affinity configuration of the calmodulin-melittin complex displays an affinity constant greater than or equal to 10(7) M-1, i.e. 2 orders of magnitude higher than that of free calmodulin; the latter is even more entropy driven (delta H0 = 7.2 kJ X site-1; delta S0 = 158 J X K-1 X site-1) than binding to free calmodulin (delta H0 = 4.7 kJ X site-1; delta S0 = 112 J X K-1 X site-1), thus underlining the importance of hydrophobic forces in the free energy coupling involved in the ternary complex.     

Increased Cell Proliferation and Neurogenesis in the Hippocampal Dentate Gyrus of Old GFAP<Superscript>−/−</Superscript>Vim<Superscript>−/−</Superscript> Mice

In response to central nervous system (CNS) injury, and more discretely so also during aging, astrocytes become reactive and increase their expression of the intermediate filament proteins glial fibrillary acidic protein (GFAP) and vimentin. Studies of mice deficient in astrocytic intermediate filaments have provided insights into the function of reactive gliosis. Recently we demonstrated robust integrationof retinal transplants (1) and increased posttraumatic synaptic regeneration (2) in GFAP^–/–Vim^–/– mice, suggesting that modulation of astrocyte activity affects the permissiveness of the CNS environment for regeneration. Neurogenesis in the adult mammalian CNS is restricted to essentially two regions, the hippocampus and the subventricular zone. Here, we assessed neurogenesis in the hippocampus of 18-month-old GFAP^–/–Vim^–/– mice. In the granular layer of the dentate gyrus, cell proliferation/survival was 34% higher and neurogenesis 36% higher in GFAP^–/–Vim^–/– mice than in wildtype controls. These findings suggest that the adult hippocampal neurogenesis in healthy old mice can be increased by modulating astrocyte reactivity.Special issue dedicated to Lawrence. F. Eng.     

Miniaturized separation techniques in glycomic investigations

High-sensitivity glycomic analyses are becoming of a great interest in modern biomedical and clinical research, as well as in the development of recombinant protein products. The evolution of separation techniques for glycomic analysis at high sensitivity is highlighted in this review. These methodologies include capillary liquid chromatography, capillary electrophoresis (CE) and capillary electrochromatography (CEC). The potential of such methodologies in glycomic analysis is demonstrated for model glycoproteins as well as total glycomes derived from biological samples.     

Nutrient-dependent expression of insulin-like peptides from neuroendocrine cells in the CNS contributes to growth regulation in Drosophila

BACKGROUND: The insulin/IGF-1 signaling pathway controls cellular and organismal growth in many multicellular organisms. In Drosophila, genetic defects in components of the insulin signaling pathway produce small flies that are delayed in development and possess fewer and smaller cells as well as female sterility, reminiscent of the phenotypes of starved flies. RESULTS: Here we establish a causal link between nutrient availability and insulin-dependent growth. We show that in addition to the Drosophila insulin-like peptide 2 (dilp2) gene, overexpression of dilp1 and dilp3-7 is sufficient to promote growth. Three of the dilp genes are expressed in seven median neurosecretory cells (m-NSCs) in the brain. These m-NSCs possess axon terminals in the larval endocrine gland and on the aorta, from which DILPs may be released into the circulatory system. Although expressed in the same cells, the expression of the three genes is controlled by unrelated cis-regulatory elements. The expression of two of the three genes is regulated by nutrient availability. Genetic ablation of these neurosecretory cells mimics the phenotype of starved or insulin signaling mutant flies. CONCLUSIONS: These results point to a conserved role of the neuroendocrine axis in growth control in multicellular organisms.     

Targeting the superoxide/nitric oxide ratio by L-arginine and SOD mimic in diabetic rat skin

Abstract

Setting the correct ratio of superoxide anion (O₂^?-) and nitric oxide (^?NO) radicals seems to be crucial in restoring disrupted redox signaling in diabetic skin and improvement of ^?NO physiological action for prevention and treatment of skin injuries in diabetes. In this study we examined the effects of L-arginine and manganese(II)-pentaazamacrocyclic superoxide dismutase (SOD) mimic – M40403 in diabetic rat skin. Following induction of diabetes by alloxan (blood glucose level ≥12?mMol l?^?1) non-diabetic and diabetic male Mill Hill hybrid hooded rats were divided into three subgroups: (i) control, and receiving: (ii) L-arginine, (iii) M40403. Treatment of diabetic animals started after diabetes induction and lasted for 7 days. Compared to control, lower cutaneous immuno-expression of endothelial NO synthase (eNOS), heme oxygenase 1 (HO1), manganese SOD (MnSOD) and glutathione peroxidase (GSH-Px), in parallel with increased NFE2-related factor 2 (Nrf2) and nitrotyrosine levels characterized diabetic skin. L-arginine and M40403 treatments normalized alloxan-induced increase in nitrotyrosine. This was accompanied by the improvement/restitution of eNOS and HO1 or MnSOD and GSH-Px protein expression levels in diabetic skin following L-arginine, i.e. SOD mimic treatments, respectively. The results indicate that L-arginine and M40403 stabilize redox balance in diabetic skin and suggest the underlying molecular mechanisms. Restitution of skin redox balance by L-arginine and M40403 may represent an effective strategy to ameliorate therapy of diabetic skin.