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Konstantinos Stefanidis Dimitris Loutradis Vasiliki Anastasiadou Panagiotis Beretsos Ritsa Bletsa Vasiliki Dinopoulou Kaliopi Lekka Evangelia Elenis Erasmia Kiapekou Stauros Koussoulakos Anastasios Fotinos Aris Antsaklis 《Bio Systems》2009,98(2):122-126
Oxytocin is a nine amino acid peptide involved in a wide spectrum of physiological functions; predominantly those concerning reproduction and differentiation are of interest. Oxytocin receptors are expressed at early developmental stages of mammals, suggesting that oxytocin might be involved in the determination of the germ stem cell line, at the very early stages of mammalian development. In this respect, the proximate aim of the present study was to confirm and further analyze the existence of oxytocin receptors at a very early level of cell commitment, that is, the determination of germ cells derived from embryoid bodies. To achieve our purpose we have cultured mouse embryonic stem cells under conditions inducing formation of embryoid bodies. In this work, ES cells were allowed to aggregate in a novel medium, “Stefanidis medium” from day 0 to day 14 until formed EBs. RNA was isolated from EBs and using RT-PCR we showed that EBs expressed Oct-4, OTR, OT, and DAZL. To demonstrate simultaneous expression immunocytochemistry was preformed, in which EBs showed strong immunoreactivity for both, OTR and DAZL molecular markers. We found that 35% of the cells displayed OTR, using flow cytometry. In addition, this novel medium showed to increase OTR mRNA. We propose, that at least in murine induced embryoid bodies there is simultaneous expression of oxytocin receptors and germ cell markers (DAZL) in many cells (expressing Oct-4). We thus conclude that, the oxytocin might indeed be a molecule playing a leading role in germ cell determination. 相似文献
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Erasmia Giannakou Nickos Aggeloussis Adamantios ArampatzisAuthor vitae 《Journal of electromyography and kinesiology》2011,21(6):1081-1086
The purpose of this study was to assess the reproducibility of fascicle length (FL) and pennation angle (PA) of gastrocnemius medialis (GM) muscle during running in vivo. Twelve male recreational long distance runners (mean ± SD; age: 24 ± 3 years, mass: 76 ± 7 kg) ran on a treadmill at a speed of 3.0 m/s, wearing their own running shoes, for two different 10 min sessions that were at least 2 days apart. For each test day 10 acceptable trials were recorded. Ankle and knee joint angle data were recorded by a Vicon 624 system with three cameras operating at 120 Hz. B-mode ultrasonography was used to examine fascicle length and pennation angle of gastrocnemius medialis muscle. The ultrasound probe was firmly secured on the muscle belly using a lightweight foam fixation. The results indicated that fascicle length and pennation angle demonstrated high reproducibility values during treadmill running both for within and between test days. The root mean square scores between the repeated waveforms of pennation angle and fascicle length were small (∼2° and ∼3.5 mm, respectively). However, ∼14 trials for pennation angle and ∼9 trials for fascicle length may be required in order to record accurate data from muscle architecture parameters. In conclusion, ultrasound measurements may be highly reproducible during dynamic movements such as treadmill running, provided that a proper fixation is used in order to assure the constant location and orientation of the ultrasound probe throughout the movement. 相似文献
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Background, Aims and Scope Telework is associated with a number of costs and benefits, including reduced company overhead costs, need for office and
parking space, office energy consumption, increased productivity, reduced absenteeism, retention of specialized employees,
reduction in transportation-related fuel consumption and air pollution, and many others. This paper applies a systems model
to telework and nontelework scenarios to quantify direct energy and fuel costs and external costs related to air emissions
from transportation, heating, cooling, lighting, and electronic and electrical equipment use both at the company and the home
office, including rebound effects.
Methods E-COMMUTair, a scalable web-based tool created by the authors and designed to assess the air pollution effects of individual
or company telework programs versus nontelework is employed along with Monte Carlo simulation and sensitivity analysis. E-COMMUTair
is using the latest available U.S. energy use and air emission factors. The external costs of air emissions are estimated.
The role of telecommuting frequency is emphasized, and differences between various states are explored. The paper identifies
the drivers of external costs, and presents an example breakeven analysis focused on CO2 and key model parameters.
Results and Discussion Nontelework’s external costs are equal to or higher than telework’s costs for every model component, demonstrating that telework
programs could provide benefits, including monetary benefits, to society. Transportation is the major contributor to the total
costs, with home heating and cooling, and office cooling following. Most of the monetary costs associated with transportation
are borne by individuals rather than society. Teleworking employees increase their home-related expenses but reduce their
travel-related expenses, ending up with smaller total costs. Energy and fuel costs get reduced in the office space when telework
programs are applied, resulting in benefits to companies. Energy and external costs decrease as telework frequency increases.
When compared to not teleworking, 5-day telework scenarios on cooling days in California can have about 50–70% lower total
costs. The probabilistic analysis confirms the results of the deterministic analysis. The sensitivity analysis reveals that
for the nontelework scenario, transportation-related variables such as commuting distance and average number of passengers
affect CO2, CO, and NOx emissions, while for the telework part, frequency and the number of roundtrips are the most relevant.
Conclusions Both analyses show that telework programs have the potential to lower both energy and external costs creating a favorable
bottom line for society, employees, and companies by decreasing tailpipe emissions, lowering transportation costs, and decreasing
energy costs at the company office. However, important parameters such as telecommuting frequency, characteristics of the
office and home space, climate patterns, and rebound effects that determine external costs along with the price of gasoline,
electricity and natural gas in the state where the program is implemented can greatly influence the final results, and should
be carefully examined.
Recommendations and Perspectives The effects of telework programs on people’s daily lives are complex and difficult to predict and quantify. The current analysis
showed that significant financial benefits can be expected from telework programs, but as seen often in environmental policy-making,
the details of implementation will make or break the success of a program.
formerly Postdoctoral Researcher, University of California, Berkeley
ESS-Submission Editor: Dr. Gerald Rebitzer (Gerald.Rebitzer@alcan.com) 相似文献
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Xanthou G Alissafi T Semitekolou M Simoes DC Economidou E Gaga M Lambrecht BN Lloyd CM Panoutsakopoulou V 《Nature medicine》2007,13(5):570-578
Osteopontin (Opn) is important for T helper type 1 (T(H)1) immunity and autoimmunity. However, the role of this cytokine in T(H)2-mediated allergic disease as well as its effects on primary versus secondary antigenic encounters remain unclear. Here we demonstrate that OPN is expressed in the lungs of asthmatic individuals and that Opn-s, the secreted form of Opn, exerts opposing effects on mouse T(H)2 effector responses and subsequent allergic airway disease: pro-inflammatory at primary systemic sensitization, and anti-inflammatory during secondary pulmonary antigenic challenge. These effects of Opn-s are mainly mediated by the regulation of T(H)2-suppressing plasmacytoid dendritic cells (DCs) during primary sensitization and T(H)2-promoting conventional DCs during secondary antigenic challenge. Therapeutic administration of recombinant Opn during pulmonary secondary antigenic challenge decreased established T(H)2 responses and protected mice from allergic disease. These effects on T(H)2 allergic responses suggest that Opn-s is an important therapeutic target and provide new insight into its role in immunity. 相似文献
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