Perceived Stress at Work Is Associated with Lower Levels of DHEA-S

Background

It is known that long-term psychosocial stress may cause or contribute to different diseases and symptoms and accelerate aging. One of the consequences of prolonged psychosocial stress may be a negative effect on the levels of dehydroepiandrosterone (DHEA) and its sulphated metabolite dehydroepiandrosterone sulphate (DHEA-S). The aim of this study is to investigate whether levels of DHEA and DHEA-S differ in individuals who report perceived stress at work compared to individuals who report no perceived stress at work.

Methods

Morning fasting DHEA-S and DHEA levels were measured in serum in a non-stressed group (n = 40) and a stressed group (n = 41). DHEA and DHEA-S levels were compared between the groups using ANCOVA, controlling for age.

Results

The mean DHEA-S levels were 23% lower in the subjects who reported stress at work compared to the non-stressed group. Statistical analysis (ANCOVA) showed a significant difference in DHEA-S levels between the groups (p = 0.010). There was no difference in DHEA level between the groups.

Conclusions

This study indicates that stressed individual have markedly lower levels of DHEA-S. Given the important and beneficial functions of DHEA and DHEA-S, lower levels of DHEA-S may constitute one link between psychosocial stress, ill health and accelerated ageing.     

The millipede family Polydesmidae in Taiwan, with descriptions of five new species (Polydesmida, Diplopoda)

Polydesmidae are represented in Taiwan by seven species in two genera. Neither of the genera is endemic to Taiwan, but six of the species are, including five new: Nipponesmus minorsp. n., Epanerchodus bispinosussp. n., Epanerchodus curtigonopussp. n., Epanerchodus flagellifersp. n. and Epanerchodus pinguissp. n. In addition, the diagnosis of the hitherto enigmatic genus Nipponesmus Chamberlin & Wang, 1953 is refined vis-à-vis the especially similar, Central Asian, Siberian and Eastern European genus Schizoturanius Verhoeff, 1931, chiefly based on new material of the type-species Nipponesmus shirinensis Chamberlin & Wang, 1953; this species is adequately redescribed and represents still another Taiwanese endemic. A key to all three currently known species of Nipponesmus Chamberlin & Wang, 1953 is given. The highly speciose Central to East Asian genus Epanerchodus Attems, 1901 is represented in Taiwan by five species, all keyed, including Epanerchodus orientalis Attems, 1901, which is long known to be highly variable in Japan and found particularly polymorphous and apparently allochthonous in Taiwan. The following synonymy is formalized: Epanerchodus orientalis orientalis Attems, 1901 = Epanerchodus orientalis takakuwai Verhoeff, 1913, syn. n. The genus Usbekodesmus Lohmander, 1932 is formally synonymized with Epanerchodus Attems, 1901, syn. n., resulting in the following new formal transfers: Epanerchodus redikorzevi (Lohmander, 1932), Epanerchodus swatensis (Golovatch, 1991), Epanerchodus varius (Geoffroy & Golovatch, 2004), Epanerchodus anachoretus (Golovatch, 1986), Epanerchodus buddhis (Golovatch, 1986), Epanerchodus occultus (Golovatch, 1986), Epanerchodus sacer (Golovatch, 1987), Epanerchodus theocraticus (Golovatch, 1990) and Epanerchodus theosophicus (Golovatch, 1986), all comb. n. ex Usbekodesmus. The distributions of all seven species of Polydesmidae occurring in Taiwan are mapped and discussed.     

EST-based gene discovery in pig: virtual expression patterns and comparative mapping to human

A molecular understanding of porcine reproduction is of biological interest and economic importance. Our Midwest Consortium has produced cDNA libraries containing the majority of genes expressed in major female reproductive tissues, and we have deposited into public databases 21,499 expressed sequence tag (EST) gene sequences from the 3 end of clones from these libraries. These sequences represent 10,574 different genes, based on sequence comparison among these data, and comparison with existing porcine ESTs and genes indicate as many as 4652 of these EST clusters are novel. In silico analysis identified sequences that are expressed in specific pig tissues or organs and confirmed the broad expression in pig for many genes ubiquitously expressed in human tissues. Furthermore, we have developed computer software to identify sequence similarity of these pig genes with their human counterparts, and to extract the mapping information of these human homologues from genome databases. We demonstrate the utility of this software for comparative mapping by localizing 61 genes on the porcine physical map for Chromosomes (Chrs) 5, 10, and 14. The following Accession numbers were assigned to our deposited sequences: BF701840 – BF704551, BF708383, BF708386 – BF713604, BG322266 – BG322271, BI398567 – BI405235, BQ597354 – BQ605166.     

Second Messengers Mediate Increases in Cytosolic Calcium in Tobacco Protoplasts

Addition of membrane-permeable cyclic GMP (cGMP) and cyclic AMP (cAMP) were shown to cause elevation of cytosolic Ca²⁺ concentration ([Ca²⁺]_cyt) in tobacco (Nicotiana plumbaginofolia) protoplasts. Under the same conditions these cyclic nucleotides were shown to provoke a physiological swelling response in the protoplasts. Nonmembrane-permeable cAMP and cGMP were unable to trigger a detectable [Ca²⁺]_cyt response. Cyclic-nucleotide-mediated elevations in [Ca²⁺]_cyt involved both internal and external Ca²⁺ stores. Both cAMP- and cGMP-mediated [Ca²⁺]_cyt elevations could be inhibited by the Ca²⁺-channel blocker verapamil. Addition of inhibitors of phosphodiesterases (isobutylmethylxanthine and zaprinast) and the adenylate cyclase agonist forskolin to the protoplasts (predicted to elevate in vivo cyclic-nucleotide concentrations) caused elevations in [Ca²⁺]_cyt. Addition of the adenylate cyclase inhibitor 2′,5′-dideoxyadenosine before forskolin significantly inhibited the forskolin-induced [Ca²⁺]_cyt elevation. Taken together, these data suggest that a potential communication point for cross-talk between signal transduction pathways using cyclic nucleotides in plants is at the level of Ca²⁺ signaling.     

CRISPR/Cas9-mediated gfp gene inactivation in Arabidopsis suspension cells

Molecular Biology Reports - Targeted genome editing using CRISPR/Cas9 is a promising technology successfully verified in various plant species; however, it has hardly been used in plant cell...     

Comparison of the Wild-Type Obligate Methylotrophic Bacterium Methylophilus quaylei and its Isogenic Streptomycin-Resistant Mutant via Metal Nanoparticle Generation

Biological Trace Element Research - Metal nanoparticles synthesized by green methods with the use of microorganisms are currently one of the most closely studied types of nanomaterials. It has...     

A simple cellulose column procedure for selective enrichment of glycopeptides and characterization by nano LC coupled with electron-transfer and high-energy collisional-dissociation tandem mass spectrometry

In this report we describe an on-column method for glycopeptide enrichment with cellulose as a solid-phase extraction material. The method was developed using tryptic digests of several standard glycoproteins and validated with more complex standard protein digest mixtures. Glycopeptides of different masses containing neutral and acidic glycoforms of both N- and O-linked sugars were obtained in good yield by this method. Upon isolation, glycopeptides may be subjected to further glycoproteomic and glycomic workflows for the purpose of identifying glycoproteins present in the sample and characterizing their glycosylation sites, as well as their global and site-specific glycosylation profiles at the glycopeptide level. Detailed structural analysis of glycoforms may then be performed at the glycan level upon chemical or enzymatic release of the oligosaccharides. Aiming at complementing other purification methods, this technique is extremely simple, cost-effective, and efficient. Glycopeptide enrichment was verified and validated by nano liquid chromatography-tandem mass spectrometry (LC-MS/MS) combining electron-transfer dissociation (ETD) and collision-activated dissociation (CAD) fragmentation techniques.