The role of AMPK and CREB-1 in the regulation of mitochondrial biogenesis during muscle differentiation

The aim of the study was to identify main regulators of mitochondrial biogenesis in a skeletal muscle differentiation model. To investigate candidate factors we used the cytochrome c promoter as a representative promoter since cytochrome c levels correlate well with respiratory chain complexes. We chose the AMP activated kinase (AMPK) and cyclic AMP-response element binding protein 1 (CREB-1) as promising candidates, which could control the process of mitochondrial proliferation. To analyze whether AMPK regulates the cytochrome c promoter, a cell line stably expressing a constitutively active AMPKalpha1-CA was generated. Indeed, AMPKalpha1-CA kinase activity was found to be increased in these clones. However, AMPKalpha1-CA and dominant negative AMPKalpha constructs did not change cytochrome c promoter activity in reporter gene assays, total AMPK activity was unchanged during muscle differentiation suggesting that it is not involved in the regulation of mitochondrial biogenesis in this model. In contrast, the constitutively active CREB construct, C2/CREB, elevated cytochrome c promoter activity. This increased promoter activity was diminished in the presence of a dominant negative CREB (A-CREB) construct showing that CREB-1 directly activates the cytochrome c promoter. Western blot analysis revealed two different CREB-1 isoforms: CREB-1alpha and CREB-1delta. Myoblasts contain predominantly CREB-1delta, while myotubes have preferably the CREB-1alpha isoform. The phosphorylation state of these isoforms changed in parallel with their protein levels suggesting a functional isoform switch during differentiation. Two appropriate, alternatively spliced isoforms of CREB-1 mRNA were found but their ratio did not change during differentiation. This suggests that posttranslational modifications and/or recruitment of the CREB-1 isoforms by other factors of the transcriptional complex play a dominant role in determining their cellular levels. To elucidate, which upstream factors regulate the activity of CREB-1, kinase and phosphatase inhibitors were used. A PKA activator and two phosphatase inhibitors increased the phosphorylation of CREB-1 at Ser-133, which is thought to be necessary for its activation. Furthermore, Cyclosporin A not only enhanced phosphorylation of CREB-1, but also the cytochrome c promoter activity. Therefore, it is likely that PP2B (calcineurin) regulates the phosphorylation of CREB-1 during muscle differentiation. Intracellular resting calcium levels were found to be smaller in myotubes compared to myoblasts, thus changes in steady-state calcium levels seem not to be a key regulator of mitochondrial biogenesis in muscle cells. In summary, these data indicate that phosphorylation and an isoform switch of CREB-1 could play a major role in the regulation of cytochrome c promoter and thus mitochondrial biogenesis during muscle differentiation

Can the Office Environment Be a Motivator? What Makes a Good Enough Working Environment on the Eve of 2020?

A well-designed office environment is often touted as a key motivator nowdays, although it is not entirely clear how to use it consciously. Our goal was to understand the role of the physical environment in new generation offices and whether it can be a motivator at all. We asked open-office employees to describe the three main criteria of an excellent work environment. We analyzed 509 participants' 1456 answers and classified them into 146 content codes. These content codes were further categorized based on whether they refer to the physical or/and the social environment, as well as along the eight needs Maslow described. 82.07 % of the answers referred to the physical environment, ambient stimuli dominated the sample with 324 mentions under 6 content codes (eg.: bright (128), quiet (69)). The majority (55.59 %) of the responses could be categorized under Maslow’s safety needs, but 14.15 % of them referred to one of Maslow’s growth needs (eg.: plants (26), decoration (21)). Using the intersection of Maslow's and Herzberg's theory, we argue that certain physical environmental aspects can be considered as a hygiene factor, some of them as a motivator. And some of them as both meaning some aspects can be considered on more level from an emotional-motivational perspective. Planning an office is not just an architectural question, but a psychological one as well. In order to design human-focused work places we need to understand the exact role and the layering of the physical environmental aspects

Separate hydrolysis and co-fermentation for improved xylose utilization in integrated ethanol production from wheat meal and wheat straw

<p>Abstract</p> <p>Background</p> <p>The commercialization of second-generation bioethanol has not been realized due to several factors, including poor biomass utilization and high production cost. It is generally accepted that the most important parameters in reducing the production cost are the ethanol yield and the ethanol concentration in the fermentation broth. Agricultural residues contain large amounts of hemicellulose, and the utilization of xylose is thus a plausible way to improve the concentration and yield of ethanol during fermentation. Most naturally occurring ethanol-fermenting microorganisms do not utilize xylose, but a genetically modified yeast strain, TMB3400, has the ability to co-ferment glucose and xylose. However, the xylose uptake rate is only enhanced when the glucose concentration is low.</p> <p>Results</p> <p>Separate hydrolysis and co-fermentation of steam-pretreated wheat straw (SPWS) combined with wheat-starch hydrolysate feed was performed in two separate processes. The average yield of ethanol and the xylose consumption reached 86% and 69%, respectively, when the hydrolysate of the enzymatically hydrolyzed (18.5% WIS) unwashed SPWS solid fraction and wheat-starch hydrolysate were fed to the fermentor after 1 h of fermentation of the SPWS liquid fraction. In the other configuration, fermentation of the SPWS hydrolysate (7.0% WIS), resulted in an average ethanol yield of 93% from fermentation based on glucose and xylose and complete xylose consumption when wheat-starch hydrolysate was included in the feed. Increased initial cell density in the fermentation (from 5 to 20 g/L) did not increase the ethanol yield, but improved and accelerated xylose consumption in both cases.</p> <p>Conclusions</p> <p>Higher ethanol yield has been achieved in co-fermentation of xylose and glucose in SPWS hydrolysate when wheat-starch hydrolysate was used as feed, then in co-fermentation of the liquid fraction of SPWS fed with the mixed hydrolysates. Integration of first-generation and second-generation processes also increases the ethanol concentration, resulting in a reduction in the cost of the distillation step, thus improving the process economics.</p

Amatőr hosszútávfutók folyadékfogyasztásának vizsgálata a dehidratáció tükrében = Research about the Fluid Consumption of Amateur Long Distance Runners Perspective of the Dehydration

Célkitűzés: Vizsgálatunkban arra keressük a választ, hogy a különböző italok miként befolyásolják a futók teljesítményét és szervezetük dehidratációs szintjét futás alatt. Anyag és módszerek: A vizsgálatba 40 főt vontunk be, akik 21 km-es versenyen vettek részt. A futókat két csoportba soroltuk, „Edzett”, illetve „Nem edzett”. Mindkét csoportból kiválasztottunk 10-10 főt, akik sportitalt, illetve vizet fogyasztottak. A vizsgálatban kitöltettünk a futókkal egy 29 kérdéses kérdőívet, majd vizeletmintát vettünk futás előtt és után, valamint vizsgáltuk a testösszetételeket, a szervezet folyadékmennyiségét és annak változását. A kapott eredményekből megpróbáltuk meghatározni, hogy a sportolók szervezete a különböző italok fogyasztása mellett mennyire dehidratálódik a verseny alatt. Eredmények: A vizsgálatban a sportitalt fogyasztó futók 80%-a jobb teljesítményről, kevesebb dehidratációs tünetről számolt be. A testösszetétel-vizsgálat is azt támasztotta alá, hogy a sportitalt fogyasztók szervezete kevésbe volt kiszáradva. A vizet fogyasztó sportolók 100%-ánál kimutathatók voltak a dehidratáció jelei. Introduction: In our experiment, we wanted to establish to what expert the isotonic drinks infl uence the results of the athletes running a semi-marathon (21 km). Material and Methods: The study included 40 persons who ran in the semi-marathon (21 km). According to their fitness we divided them into 2 groups. The athletes who run more than 30 km a week were included in the trained group and those who run less than 30 km were included in the nontrained group. We chose 10 persons from each group who drank isotonic drinks and 10 who drank only water. During the race, the runners had to drink to same amount of liquid. In the first part of our experiment we asked the participants to complete a questionnaire with 29 questions. They were asked about their training level, if they know anything about dehydration if they had already experienced its symptoms. In the second part of the experiment we took urine samples before and after running and we measured the quantity and changes of the liquid as well as the compounds of the body. From the results, we tried to establish how much the sportsmen dehydrated during the race taking also into consideration the different liquids they drank. Results: 80% of the sportsmen from both groups, trained and non-trained, who drank isotonic drinks reported less symptoms of dehydration in comparison with those who drank only water during the semimarathon. We could establish the final results from the questionnaire what the runners completed after the race. The study of the body compounds also certified that the athletes who drank the isotonic drinks were less dehydrated. They lost only 1% of their body water. The sportsmen who drank only water all showed dehydration at different levels, the highest one being almost 5% of the body water. The density of the urine showed similar values. The density of the urine of those who drank only water more significantly (p<0.05

A munkaterek használatának átalakulása a megosztott munkaállomásos rendszer bevezetésével

Háttér és célkitűzések: A tanulmányunkban közölt feltáró környezetpszichológiai esettanulmány egy nyugat-magyarországi nagyvállalat irodai munkavállalói körében készült terepvizsgálat része. A vállalat a klasszikus, nyitott terű, saját munkaállomásos irodai rendszerről részlegesen shared desk elrendezésre váltott. Feltételezésünk szerint (1) a térszervezés átalakulása kapcsán a korábbi rendszer alacsony hely-használó illeszkedései fellazulnak, és helyettük új, nagyobb mértékű illeszkedések alakulnak ki, illetve (2) a szervezeten belül a shared desk használatának elterjedésével a térhasználat is differenciálódik. Módszer: Fél éven át, longitudinális dizájnban vizsgáltuk az átállást online kérdőíves módszerrel: a résztvevőknek a munkavégzésükhöz kapcsolódó aktivitásokat, illetve érzelmi viszonyulásokat kellett párosítaniuk helyszínekhez . 3 mérési időpontban összesen 235 kérdőívet elemeztünk, a tevékenységek és érzelmi viszonyulások lokalizációjának időbeli változását kereszttábla-elemzéssel vizsgáltuk. Eredmények: A szervezeten belül a legjellemzőbb feladattípusnak számító egyedüli, koncentrált munkavégzés lokalizációjában kaptuk a legmarkánsabb változást, szignifikáns átrendeződést tapasztaltunk továbbá a fontos szakmai telefonhívás elintézése, valamint az egyedül inspirálódás tevékenységek lokalizációjában is. Az érzések tekintetében a biztonság és bizonytalanság lokalizációjában tapasztaltunk szignifikáns átrendeződést. Következtetések : Az eredmények mentén elmondható, hogy a legalacsonyabb illeszkedésű feladatok spontán relokalizálódtak a shared desk bevezetésével, és a térhasználat is differenciálódott. Ez a markáns változás kezdetben bizonytalanságot is generált, ami a 6 hónapos mérés idejére rendeződni tudott, a biztonságosnak tartott helyek sora azonban átrendeződött

Transformation of the office

Purpose: The purpose of this paper is to present an environmental psychological case study regarding an office design change. The employees of the researched company had the chance to decide whether to stay in the classic open office set-up or to switch to a shared desk supplemented by a one-day-a-week home office possibility. The authors examined the development of participants’ territorial behaviour and place attachment. Design/methodology/approach: The given organizational situation is a quasi-experimental design; the variables were examined via questionnaire in a longitudinal model. Quantitative measurement was supplemented with focus group discussions. Findings: The degree of personalization (a type of territorial behaviour) decreased significantly not only among those who lost their permanent workstations – as we expected – but also in the entire population. Workplace attachment stagnated for the entire population, but workstation attachment showed a significant decrease among those who switched to the shared desk. Research limitations/implications: The limitations and the advantages are also followed by the nature of a case study: high ecological validity with relatively low sample size. Practical implications: Redesigning an office is never just an economic or interior design issue, but a psychological one. This paper provides practical environmental psychological insights into implementing office designs without permanent individual workstations. Originality/value: This paper presents the environmental psychological background of shared desk design implementation. The authors point out the significance of repressing personalization behaviour and as per the authors’ knowledge, they are the first to introduce the concept of workstation attachment