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991.
We decided to study the effect of glucose deprivation on glycosaminoglycan (GAG) synthesis and degradation in fibroblast cultures, vitality of these cells and a correlation of these processes with the expression of oxygen/glucose-regulated proteins (ORP150/GRP170). The incorporation of [3H]-glucosamine into both newly synthesised hyaluronic acid and sulphated GAGs and [35S]-sulphate into GAGs was used as an index of glycosaminoglycan synthesis. Quantitative evaluation of newly synthesised GAGs degradation was determined by pulse-chase experiments. We demonstrated that fibroblasts incubated in high glucose medium synthesised significant amounts of GAGs. Most of them were secreted into the culture medium. The shortage of glucose resulted in about 40% reduction in synthesis of GAGs, both those secreted into culture medium and remaining in the cell layer. The pulse-chase experiments demonstrated that the reduced amount of newly synthesised glycosaminoglycans was protected against intracellular degradation. Proportionally less GAGs were degraded in cultures incubated in low glucose than in high glucose media. These phenomena were accompanied by an increase in the expression of chaperon – ORP150 in cultures growing in low glucose medium. We suggest that the increased expression of ORP150 is a factor which prolongs the cell vitality and protects glycosaminoglycans against intracellular degradation induced by glucose deprivation. 相似文献
992.
Teresa Warchoł Margarita Lianeri Jan K. Łącki Paweł P. Jagodziński 《Molecular biology reports》2010,37(7):3121-3125
It has been reported that stromal cell-derived factor-1 (SDF1), currently also designated CXCL12, plays a significant role
in the development of nephritis and death in the lupus mice model. Using restriction length fragment polymorphism (RFLP) analysis
we assessed the frequencies of SDF1-3′ G801A (rs 1801157) polymorphic variants between systemic lupus erythematosus (SLE) patients (n = 150) and controls (n = 300). There were no significant differences in the prevalence of SDF1-3′ G801A polymorphic variants in SLE patients and healthy individuals. However, we observed that the SDF1-3′ A/A and G/A genotypes (recessive model) contributed to renal manifestations of SLE OR = 3.042 (95% CI = 1.527–6.058, P = 0.002), and the p value stayed statistically significant after Bonferroni correction (p
corr = 0.032) in SLE patients. We also found an association of the SDF1-3′ A/A and G/A genotypes (recessive model) with dermal manifestations of SLE OR = 2.510 (95% CI = 1.247–5.052, P = 0.0122), (p
corr = 0.1952) but this did not remain statistically significant after Bonferroni correction. Our observations suggest that the
SDF1-3′ G801A genotype may be associated with some clinical manifestations in patients with SLE. 相似文献
993.
Magdalena Szechyńska-Hebda Jerzy Kruk Magdalena Górecka Barbara Karpińska Stanis?aw Karpiński 《The Plant cell》2010,22(7):2201-2218
Although light is essential for photosynthesis, excess light can damage the photosynthetic apparatus and deregulate other cellular processes. Thus, protective integrated regulatory responses that can dissipate excess of absorbed light energy and simultaneously optimize photosynthesis and other cellular processes under variable light conditions can prove highly adaptive. Here, we show that the local and systemic responses to an excess light episode are associated with photoelectrophysiological signaling (PEPS) as well as with changes in nonphotochemical quenching and reactive oxygen species levels. During an excess light incident, PEPS is induced by quantum redox changes in photosystem II and in its proximity and/or by changes in glutathione metabolism in chloroplasts. PEPS is transduced, at least in part, by bundle sheath cells and is light wavelength specific. PEPS systemic propagation speed and action potential are dependent on ASCORBATE PEROXIDASE2 function. Excess light episodes are physiologically memorized in leaves, and the cellular light memory effect is specific for an excess of blue (450 nm) and red (650 nm) light of similar energy. It is concluded that plants possess a complex and dynamic light training and memory system that involves quantum redox, reactive oxygen species, hormonal, and PEPS signaling and is used to optimize light acclimation and immune defenses. 相似文献
994.
Włodzimierz Mrówczyński Jan Celichowski Piotr Krutki Teresa Górska Henryk Majczyński Urszula Sławińska 《Journal of electromyography and kinesiology》2010,20(3):523-531
The contractile properties of motor units (MUs) were electrophysiologically investigated in the medial gastrocnemius (MG) muscle in 17 Wistar three-month-old female rats: 14, 30, 90 and 180 days after the total transection of the thoracic spinal cord and compared to those in intact (control) rats. A sag phenomenon, regularly observed in unfused tetani of fast units in intact animals at 40 Hz stimulation, almost completely disappeared in spinal rats. Therefore, the MUs of intact and spinal rats were classified as fast or slow types basing on 20 Hz tetanus index, the value of which was lower or equal 2.0 for fast and higher than 2.0 for slow MUs. The MUs composition of MG muscle changed with time after the spinal cord transection: an increasing proportion of fast fatigable (FF) units starting one month after injury and a disappearance of slow (S) units within the three months were observed. In all MUs investigated the twitch contraction and half-relaxation time were significantly prolonged after injury (p < 0.01, Mann–Whitney U-test). Moreover, a decrease of the fatigue index for fast resistant (FR) and slow MUs was observed in subsequent groups of spinal rats. No significant changes were found between twitch forces in all MU types of spinal animals (p > 0.05). However, due to a decrease of the maximal tetanic force, a significant rise of the twitch-to-tetanus ratio of all MUs in spinal rats was detected (p < 0.01). The considerable reduction of ability to potentiate the force was noticed for fast, especially FF type MUs. In conclusion, the spinal cord transection leads to changes in the proportion of the three MU types in rat MG muscle. The majority of changes in MUs’ contractile properties were developed progressively with time after the spinal cord injury. However, the most intensive alterations of twitch-time parameters were observed in rats one month after the transection. 相似文献
995.
Mitochondrial genomes are frequently used to infer phylogenetic relationships. Some taxa are, however, poorly represented.
To facilitate better understanding of the potential of mitochondrial genome data in freshwater mussels, we present here, for
the first time, the mitochondrial sequences of 4 complete F-type mitochondrial genomes from the European freshwater bivalveUnio pictorum (Unionidae). These genomes are very compact (15 761 bp) but have a typical gene complement for bilaterian mitochondrial genomes
and a very similar organization to other unionid genomes available in databases. Very low nucleotide diversity within the
species suggests a small effective population size of PolishU. pictorum, a phenomenon of potential importance for environmental management policies. 相似文献
996.
Oxidative stress during aging of Saccharomyces cerevisiae in stationary culture was documented by demonstration of progressive increase in the formation of superoxide, decrease in the content of acid‐soluble thiols and of acid‐soluble antioxidant capacity of cell extracts, and accumulation of aldehydes and protein carbonyl groups in two yeast strains and decreases in activities of antioxidant enzymes. Cells of a CuZn‐SOD (superoxide dismutase)‐1‐deficient strain showed a higher loss of viability than cells of an isogenic wild‐type strain. Cell survival was augmented, and changes in biochemical parameters were ameliorated, by addition of exogenous antioxidants (ascorbic acid, glutathione and melatonin) in both strains. 相似文献
997.
Mariola Kuczer Katarzyna Dziubasik Anna Midak‐Siewirska Renata Zahorska Mirosław Łuczak Danuta Konopińska 《Journal of peptide science》2010,16(4):186-189
The subject of these studies was synthesis and determination of biological properties of a series of insect peptides, such as alloferon, Any‐GS and their analogues. The synthesis of 14 peptides was performed by the solid‐phase method. Biological effect of these peptides was evaluated by the antiviral test against Human Herpes Virus type 1 (HHV‐1) in vitro using a Vero cell line. It was found that the investigated peptides inhibit the replication of HHV‐1 in Vero cells. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
998.
A. Kasperowicz P. Pristaš M. Piknová P. Javorský W. Guczyńska T. Michałovski E. Kwiatkowska 《Anaerobe》2010,16(4):387-392
Enzymes in the newly described rumen bacterium, Treponema zioleckii strain kT, capable of digesting Timothy grass fructan, inulin, and sucrose were identified and characterized. Two specific endolevanases and one non-specific β-fructofuranosidase were found in a cell-free extract. The molecular weight of the endolevanases were estimated to be 60 and 36 kDa, whereas that of β-fructofuranosidase, 87 kDa. The former of the specific enzymes was associated with the outer membrane, while the latter and the non-specific β-fructofuranosidase, with the periplasm or cytosol. The Km and Vmax for Timothy grass fructan degradation by endolevanase were 0.27% and 15.75 μM fructose equivalents × mg protein?1 × min?1, those for sucrose and inulin digestion by β-fructofuranosidase were 1.35 × 10?3 M and 1.73 μM hexoses × mg protein?1 × min?1 and 1.77% and 1.83 μM hexoses × mg protein?1 × min?1, respectively. 相似文献
999.
D. Kabzińska E. Sinkiewicz-Darol I. Hausmanowa-Petrusewicz A. Kochański 《Journal of applied genetics》2010,51(2):203-209
Among 57 mutations in the peripheral myelin protein 22 gene (PMP22) identified so far in patients affected by Charcot-Marie-Tooth disease (CMT), only 8 have been shown to segregate with a
mixed phenotype of CMT and hearing impairment. In this study, we report a new Ser1 12Arg mutation in thePMP22 gene, identified in a patient with early-onset CMT and slowly progressive hearing impairment beginning in the second decade
of life. We suggest that the Ser1 12Arg mutation in thePMP22 gene might have a causative role in the early-onset CMT with hearing impairment. Thus, our study extends the spectrum of
CMT phenotypes putatively associated withPMP22 gene mutations. 相似文献
1000.
M. Król K. M. Pawłowski J. Skierski P. Turowski A. Majewska J. Polańska M. Ugorski R. E. Morty T. Motyl 《Journal of applied genetics》2010,51(2):169-183
In light of the high incidence of mammary cancer in dogs and completion of the canine genome sequencing, the new possibilities
of gene profiling by using DNA microarrays give hope to veterinary oncology. The cell lines isolated from mammary tumors are
a valuable tool in developing and testing new pathway-specific cancer therapeutics. Differential cytometric analysis of 6
canine mammary cancer cell lines was performed. We divided cell lines into 3 groups based on their phenotype: 2 lines with
high proliferative potential, 2 lines with high antiapoptotic potential, and 2 lines with high metastatic potential. DNA microarray
analysis revealed common genes for cell lines of each group. We found that genes encoding the receptors for growth hormone
and ghrelin are related to high proliferation rate, whileABR (active BCR-related) andTMD1 (TM2 domain containing 1) genes are related to a high antiapoptotic potential of the cancer cells. Metastatic properties
of mammary cancer cells seem to be associated with elevated expression ofPGP (P glycoprotein),SEMA3B (semaphorin 3B), andSTIM1 (stromal interaction molecule 1). 相似文献