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21.
Kaloyianni M Tsagias N Liakos P Zolota Z Christophorides E Koliakos GG 《Molecules and cells》2004,17(3):415-421
This study aims to demonstrate the effect of high glucose concentrations on NHE-1 and PK activities and investigate the implicated signal transduction pathways. Erythrocytes drawn from healthy volunteers were incubated in the presence of 5 or 50 mM of glucose, fructose, galactose or mannitol. When appropriate, specific inhibitors of NHE-1, PKC or p42/44 MAPK were used. Erythrocyte NHE-1 activity has been estimated by fluorometrical determination of the intracellular pH and quantification of sodium uptake using 22Na. Pyruvate kinase activity was measured by a NADH-lactate dehydrogenase enzymatic assay. p42/44 MAPK activity was assessed with a specific enzyme linked immunosorbent assay (ELISA). Increased concentrations of glucose but not galactose, fructose or mannitol enhanced erythrocyte NHE-1, PK and p42/44 MAPK activity. Inhibition of PKC, counteracted these effects of glucose. Similarly, inhibition of NHE 1 abolished the effect of high glucose on PK and p42/44 MAPK as well. Finally, inhibition of p42/44 MAPK also hindered the effect of glucose on NHE-1 and PK activities. The data of the present study indicate an acute effect of glucose on signal transduction pathways in human erythrocytes. This pathway involves NHE-1, PKC, and p42/44 MAPK. A positive feedback between NHE 1 and p42/44 MAPK is suggested. 相似文献
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Christentze Schmiegelow Thomas Scheike Mayke Oesterholt Daniel Minja Caroline Pehrson Pamela Magistrado Martha Lemnge Vibeke Rasch John Lusingu Thor G. Theander Birgitte Bruun Nielsen 《PloS one》2012,7(9)
Objective
To produce a fetal weight chart representative of a Tanzanian population, and compare it to weight charts from Sub-Saharan Africa and the developed world.Methods
A longitudinal observational study in Northeastern Tanzania. Pregnant women were followed throughout pregnancy with serial trans-abdominal ultrasound. All pregnancies with pathology were excluded and a chart representing the optimal growth potential was developed using fetal weights and birth weights. The weight chart was compared to a chart from Congo, a chart representing a white population, and a chart representing a white population but adapted to the study population. The prevalence of SGA was assessed using all four charts.Results
A total of 2193 weight measurements from 583 fetuses/newborns were included in the fetal weight chart. Our chart had lower percentiles than all the other charts. Most importantly, in the end of pregnancy, the 10th percentiles deviated substantially causing an overestimation of the true prevalence of SGA newborns if our chart had not been used.Conclusions
We developed a weight chart representative for a Tanzanian population and provide evidence for the necessity of developing regional specific weight charts for correct identification of SGA. Our weight chart is an important tool that can be used for clinical risk assessments of newborns and for evaluating the effect of intrauterine exposures on fetal and newborn weight. 相似文献24.
Previous spaceflight reports attribute changes in plant ultrastructure to microgravity, but it was thought that the changes might result from growth in uncontrolled environments during spaceflight. To test this possibility, potato explants were examined (a leaf, axillary bud, and small stem segment) grown in the ASTROCULTURETM plant growth unit, which provided a controlled environment. During the 16 d flight of space shuttle Columbia (STS-73), the axillary bud of each explant developed into a mature tuber. Upon return to Earth, tuber slices were examined by transmission electron microscopy. Results showed that the cell ultrastructure of flight-grown tubers could not be distinguished from that of tuber cells grown in the same growth unit on the ground. No differences were observed in cellular features such as protein crystals, plastids with starch grains, mitochondria, rough ER, or plasmodesmata. Cell wall structure, including underlying microtubules, was typical of ground-grown plants. Because cell walls of tubers formed in space were not required to provide support against the force due to gravity, it was hypothesized that these walls might exhibit differences in wall components as compared with walls formed in Earth-grown tubers. Wall components were immunolocalized at the TEM level using monoclonal antibodies JIM 5 and JIM 7, which recognize epitopes of pectins, molecules thought to contribute to wall rigidity and cell adhesion. No difference in presence, abundance or distribution of these pectin epitopes was seen between space- and Earth-grown tubers. This evidence indicates that for the parameters studied, microgravity does not affect the cellular structure of plants grown under controlled environmental conditions. 相似文献
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Wenjuan Dong Heather Mead Lei Tian Jun-Gyu Park Juan I. Garcia Sierra Jaramillo Tasha Barr Daniel S. Kollath Vanessa K. Coyne Nathan E. Stone Ashley Jones Jianying Zhang Aimin Li Li-Shu Wang Martha Milanes-Yearsley Jordi B. Torrelles Luis Martinez-Sobrido Paul S. Keim Bridget Marie Barker Michael A. Caligiuri Jianhua Yu 《Journal of virology》2022,96(1)
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Martha S. Petrovick Frances E. Nargi Theresa Towle Kristine Hogan Marie Bohane Deborah J. Wright Thomas H. MacRae Malcolm Potts Richard F. Helm 《Biotechnology and bioengineering》2010,106(3):474-481
The unique properties of mammalian cells make them valuable for a variety of applications in medicine, industry, and diagnostics. However, the utility of such cells is restricted due to the difficulty in storing them non‐frozen for an extended time and still maintaining their stability and responsiveness. In order to extend the active life span of a mammalian biosensor cell line at room and refrigerated temperatures, we have over expressed genes that are reported to provide protection from apoptosis, stress, or oxidation. We demonstrated that over expression of genes from the extremophile, Artemia franciscana, as well as GADD45β, extends room‐temperature storage of fully active cells 3.5‐fold, while over production of several anti‐apoptotic proteins extended 4°C storage 2‐ to 3‐fold. Methodologies like these that improve the stability of mammalian‐cell‐based technologies in the absence of freezers may enable widespread use of these tools in applications that have been considered impractical based solely on limited storage characteristics. Biotechnol. Bioeng. 2010; 106: 474–481. © 2010 Wiley Periodicals, Inc. 相似文献
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Markus Helfer Herwig Koppensteiner Martha Schneider Stephanie Rebensburg Sara Forcisi Constanze Müller Philippe Schmitt-Kopplin Michael Schindler Ruth Brack-Werner 《PloS one》2014,9(1)
Global HIV-1 treatment would benefit greatly from safe herbal medicines with scientifically validated novel anti-HIV-1 activities. The root extract from the medicinal plant Pelargonium sidoides (PS) is licensed in Germany as the herbal medicine EPs®7630, with numerous clinical trials supporting its safety in humans. Here we provide evidence from multiple cell culture experiments that PS extract displays potent anti-HIV-1 activity. We show that PS extract protects peripheral blood mononuclear cells and macrophages from infection with various X4 and R5 tropic HIV-1 strains, including clinical isolates. Functional studies revealed that the extract from PS has a novel mode-of-action. It interferes directly with viral infectivity and blocks the attachment of HIV-1 particles to target cells, protecting them from virus entry. Analysis of the chemical footprint of anti-HIV activity indicates that HIV-1 inhibition is mediated by multiple polyphenolic compounds with low cytotoxicity and can be separated from other extract components with higher cytotoxicity. Based on our data and its excellent safety profile, we propose that PS extract represents a lead candidate for the development of a scientifically validated herbal medicine for anti-HIV-1 therapy with a mode-of-action different from and complementary to current single-molecule drugs. 相似文献
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