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Expression of membrane and nuclear progesterone receptors in two human placental choriocarcinoma cell lines (JEG-3 and BeWo): Effects of syncytialization
This article has been made available through the Brunel Open Access Publishing Fund and is available from the specified link -
Copyright @ 2011 Spandidos Publications Ltd.A vital function of the human placenta is to produce steroid hormones such as progesterone, which are essential for the maintenance of pregnancy and the onset of parturition. Although choriocarcinoma cell lines are valuable placental models for investigations of steroid hormone actions, little is known about the expression of progesterone receptors (PRs) in these cell lines. Therefore, in this study, the expression of membrane and nuclear PRs was investigated in cultures of fusigenic (BeWo) and non-fusigenic (JEG-3) human choriocarcinoma cell lines. In addition, the effects of an inducer of syncytialization (forskolin) on the PR expression in BeWo cells were assessed. Quantitative RT-PCR revealed that in fully syncytialized BeWo cells (treated with 50 mu M forskolin for 72 h) there was a significant down-regulation of mPR alpha and up-regulation of mPR beta and of the progesterone membrane component-1 (PGRMC1) when compared with non-syncytialized BeWo cells. Expression of all the mPR and PGRMC1 mRNAs was significantly lower in JEG-3 cells compared to non-syncytialized BeWo cells. Interestingly, expression of PR-B was unaltered between the two BeWo states but was significantly higher in JEG-3 cells. Immunofluorescence analysis revealed that mPR proteins are differentially expressed in these choriocarcinoma cell lines as well as in the human placenta. The data demonstrate that human choriocarcinoma cell lines have a complex system of progesterone signalling involving multiple classes of PRs. The finding that syncytialization is accompanied by changes in the expression of these receptors may suggest that this process influences progesterone signalling
Local Ferroelectricity in SrTiO_3 Thin Films
The temperature-dependent polarization of SrTiO_3 thin films is investigated
using confocal scanning optical microscopy. A homogeneous out-of-plane and
inhomogeneous in-plane ferroelectric phase are identified from images of the
linear electrooptic response. Both hysteretic and non-hysteretic behavior are
observed under a dc bias field. Unlike classical transitions in bulk
ferroelectrics, local ferroelectricity is observed at temperatures far above
the dielectric permittivity maximum. The results demonstrate the utility of
local probe experiments in understanding inhomogeneous ferroelectrics.Comment: 8 pages, 3 figures, accepted for publication in PR
Laser Doppler technology applied to atmospheric environmental operating problems
Carbon dioxide laser Doppler ground wind data were very favorably compared with data from standard anemometers. As a result of these measurements, two breadboard systems were developed for taking research data: a continuous wave velocimeter and a pulsed Doppler system. The scanning continuous wave laser Doppler velocimeter developed for detecting, tracking and measuring aircraft wake vortices was successfully tested at an airport where it located vortices to an accuracy of 3 meters at a range of 150 meters. The airborne pulsed laser Doppler system was developed to detect and measure clear air turbulence (CAT). This system was tested aboard an aircraft, but jet stream CAT was not encountered. However, low altitude turbulence in cumulus clouds near a mountain range was detected by the system and encountered by the aircraft at the predicted time
The Mature Market: Underlying Dimensions and Group Differences of a Potential Market for the Hotel Industry
The mature market, defined as age 55 and up and consisting of approximately 64 million Americans, is expected to increase. Studies show that this group travels more frequently, travels greater distances, and stays longer. The authors seek to determine if underlying dimensions exist for the mature individual with regard to the selection criteria for lodging when traveling for pleasure, and to determine if differences exist between various demographic subsegments of this market with regard to these underlying dimensions
Laser Doppler dust devil measurements
A scanning laser doppler velocimeter (SLDV) system was used to detect, track, and measure the velocity flow field of naturally occurring tornado-like flows (dust devils) in the atmosphere. A general description of the dust devil phenomenon is given along with a description of the test program, measurement system, and data processing techniques used to collect information on the dust devil flow field. The general meteorological conditions occurring during the test program are also described, and the information collected on two selected dust devils are discussed in detail to show the type of information which can be obtained with a SLDV system. The results from these measurements agree well with those of other investigators and illustrate the potential for the SLDV in future endeavors
The preparation of corn for dairy cows
The corn crop of Iowa exceeds in acreage, yield and value all other grain crops combined. In this state, as well as in other sections of the corn belt, corn must be relied upon as the basis of the concentrate allowance for dairy cattle, as it generally is one of the most economical sources of energy. The extent to which it is used renders it essential that the feeding of it be carefully studied, as what are apparently small economies attain large proportions when considered in the aggregate.
The preparation of corn for other types of farm livestock has been studied to some extent, but the influence of the various preparations of corn on the total yield and economy of production of milk and butterfat has received little attention. The work reported here is but a part of a series of investigations being conducted on the influence of the method of preparation of corn on the production of milk, and is a comparison of ear corn, corn-and-cob meal, and corn meal
Soybeans as a home-grown supplement for dairy cows
Soybeans, grown on the farm, give promise of providing many dairymen with a valuable protein supplement for their dairy herds which will make them independent of the purchase of high-priced protein feeds. Investigations at the Iowa Agricultural Experiment Station show that soybeans make a palatable dairy feed, that they give good results in milk production when fed in place of other protein supplements, and that pound for pound they are a third more valuable than oilmeal, with which direct comparison was made.
A home-grown supplement of that kind would be especially valuable to Iowa dairy farms. These farms easily produce all of the roughages needed for the herds in both winter and summer, such as ensilage, clover, alfalfa hay and soiling crops. It is also relatively easy for them to provide the greater portion of the grain ration, as the home-grown corn and oats should form the basis of the concentrates fed. These two feeds, however, are relatively low in protein and so are the roughages, with the exception of the legume hays. It is necessary, therefore, to secure additional concentrates which will provide the extra protein needed, especially in the ration of heavy producing cows. This is one of the main problems of dairy farming today
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