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151.
Kha Dinh Brian J. Poindexter Jennifer L. Barnes Mya C. Schiess Roger J. Bick 《Cytokine》2009,45(3):179-183
Human derived glioblastoma cells were cultured and treated with cytokines interleukin-6 (IL6), tumor necrosis factor alpha (TNF) and interferon-gamma (IFN) and imaged by fluorescence deconvolution microscopy to localize α-synuclein, tau and ubiquitin. Exposures were for short (2 h) and prolonged times (up to 96 h), with doses at both low (10 ng/ml), and high (100 ng/ml) concentrations. Further experiments used additive doses up to 200 ng/ml (2 × 100 ng), mimicking a super-infection state. Single, low doses of the cytokines initiated changes in levels of intracellular proteins, but these changes, be they increases or decreases, were not sustained, so we added higher doses of cytokine to the culture medium or fresh aliquots of cytokines over time. Finally, we treated cells with high, single doses of cytokine (200 ng/ml), to try to sustain perturbations of the proteins with cytokines. IFN caused a disruption and reduction of peripheral synuclein, TNF treatment resulted in increased levels of ubiquitin and IL6 disrupted and appeared to fragment tau. Of note, each of the proteins was found in a specific locale, tau being perinuclear, ubiquitin residing in the cytoplasm, and α-synuclein occupying the tips of cellular processes, exhibiting the characteristics of an adhesion protein/molecule [Word count = 198]. 相似文献
152.
Ichthyological Research - The spelling of the third author name was incorrectly published. 相似文献
153.
Krista Chamberlain Mya Johnson Terry-Elinor Reid Tzvia I. Springer 《Biochemistry and Biophysics Reports》2022
Multi-drug resistant infections caused by the opportunistic pathogen, Pseudomonas aeruginosa (P. aeruginosa), are a continuing problem that contribute to morbidity and mortality in immunocompromised hosts such as cystic fibrosis (CF), wound and burn patients. The bacterial toxin ExoU is one of four potent toxins that P. aeruginosa secretes into the epithelial cells of hosts. In this study, NMR Saturation Transfer Difference (STD) and in silico Schrödinger Computational Modeling were used to identify a possible binding site of a novel ligand methoctramine targeting ExoU. Future project goals will be to design a structure activity relationship (SAR) study of methoctramine and ExoU and lead to a new drug solving ExoU toxicity P. aeruginosa exerts in the clinical environment. 相似文献
154.
The acrosome reaction (AR) in bull spermatozoa was induced by the Ca2(+)-ionophore A23187, by dilauroylphosphatidylcholine or by arachidonic acid in the presence of Ca2+ in the incubation medium. The occurrence of AR was determined by following the release of acrosin from the cells. Nordihydroguaiaretic acid (NDGA), an inhibitor of both lipoxygenase and prostaglandin-synthetase, caused 35%, 43% and 69% inhibition of AR at concentrations of 1, 10 or 100 microM, respectively. Eicosatetraynoic acid (ETYA), an analogue of arachidonic acid, caused 17%, 61% and 77% inhibition of AR at concentrations of 20, 40 or 80 micrograms/ml, respectively. When AR was induced by arachidonic acid, ETYA, causes 36% and 58% inhibition at concentrations of 2 or 20 micrograms/ml, respectively. Under identical conditions, 100 microM indomethacin, a specific inhibitor of prostaglandin-synthetase, showed no inhibition but rather 35% stimulation at acrosin release rate. The fact that AR is inhibited by NDGA and not by indomethacin indicates that the lipoxygenase, rather than prostaglandin-synthetase, is involved in the mechanism of AR. Since the inhibition by NDGA is seen in the presence of the Ca-ionophore, we suggest that lipoxygenase activity is not involved in enhancing calcium transport into the cell, but rather at other steps in AR mechanism. A thin-layer chromatography revealed the presence of 15-HETE, the classical product of 15-lipoxygenase activity, which was identified by HPLC. Under AR conditions, there is an elevation of lipoxygenase products and the addition of NDGA caused a reduction in their levels. The inhibition of acrosin release by NDGA can be eliminated by adding 15-HETE or 15-HPETE to the incubation medium. In conclusion, we suggest here for the first time, a physiological role for 15-lipoxygenase in the mechanism of AR in mammalian spermatozoa. 相似文献
155.
Genes, like organisms, struggle for existence, and the most successful genes persist and widely disseminate in nature. The unbiased determination of the most successful genes requires access to sequence data from a wide range of phylogenetic taxa and ecosystems, which has finally become achievable thanks to the deluge of genomic and metagenomic sequences. Here, we analyzed 10 million protein-encoding genes and gene tags in sequenced bacterial, archaeal, eukaryotic and viral genomes and metagenomes, and our analysis demonstrates that genes encoding transposases are the most prevalent genes in nature. The finding that these genes, classically considered as selfish genes, outnumber essential or housekeeping genes suggests that they offer selective advantage to the genomes and ecosystems they inhabit, a hypothesis in agreement with an emerging body of literature. Their mobile nature not only promotes dissemination of transposable elements within and between genomes but also leads to mutations and rearrangements that can accelerate biological diversification and—consequently—evolution. By securing their own replication and dissemination, transposases guarantee to thrive so long as nucleic acid-based life forms exist. 相似文献
156.
Hypertelorism correction in the young child 总被引:3,自引:0,他引:3
J G McCarthy G S La Trenta A S Breitbart B M Zide C B Cutting 《Plastic and reconstructive surgery》1990,86(2):214-25; discussion 226-8
This series reports on 20 patients who underwent orbital hypertelorism correction under 5.3 years of age (average age 3.9 years). The patients were followed an average of 5 years, and six patients were followed in excess of 7 years with clinical and cephalometric parameters. The study demonstrated that the procedure could be safely performed at this age and was aesthetically desirable. There was minimal clinical or cephalometric evidence of skeletal orbital relapse except in three patients, for whom individual explanations are given. During the period of postoperative study, nasomaxillary growth and development proceeded as expected, except in those patients with associated clefting. All patients demonstrated increased cranial width measurements preoperatively and postoperatively, but bigonial and bimastoid measurements were generally within normal range. Excessive resection of nasoglabellar skin at the time of hypertelorism correction appeared to adversely affect nasal development. 相似文献
157.
In this paper we show that ribosomes isolated from cells inhibited for protein synthesis by the antibiotic ionophore Valinomycin can still support incorporation of [14C]-leucine into polypeptides in a cell-free system. The extent of this functional integrity depends upon the concentration of Valinomycin used and whether it acted as an ionophore or not. We demonstrate that the antibiotic acts on protein synthesis at the level of elongation and has no action either at the initiation level or as activating an RNase. Moreover, we show that it can inhibit protein synthesis at concentrations where its action as an ionophore cannot be detected. 相似文献
158.
Ichthyological Research - A new spikefish, Mephisto albomaculosus, is described based on a single specimen (94.4 mm SL) collected off Myanmar, eastern Indian Ocean in 2015. It is... 相似文献
159.
160.
Alyssa B. Novak Ellen Hines Donna Kwan Leslee Parr Mya Than Tun Han Win Frederick T. Short 《Aquatic Botany》2009,91(3):250-252
In a survey of the Myeik Archipelago, we documented seven seagrass species in the southern region. Three seagrass species (Cymodocea rotundata, Enhalus acoroides, and Halophila ovalis) have previously been reported in the Myeik Archipelago; three species (Halodule pinifolia, Halodule uninervis, Syringodium isoetifolium) are new reports for the archipelago; and one species (Thalassia hemprichii) is a new report for Myanmar. 相似文献