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41.
In a newly developed method for determining picomolar quantities of monosaccharides in glycoproteins, the methyl glycosides released by methanolysis of glycoproteins are separated as trifluoroacetates by gas-liquid chromatography and are detected with an electron capture detector. The application of the method has been demonstrated for the analysis of the carbohydrate moiety of secretory component isolated from human colostral immunoglobulin A. 相似文献
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Summary In a study of 514 spontaneous abortions, 194 were found to have a chromosome anomaly. Of these, 4 (2.1%) were unbalanced translocations. Three of the translocations were Robertsonian (13q14q) and one was reciprocal. Each translocation was ascertained independently and each was associated with a balanced rearrangement in a carrier parent. 相似文献
44.
Sandhini Saha Rohit Verma Chandan Kumar Bhoj Kumar Amit Kumar Dey Milan Surjit Sivaram V. S. Mylavarapu Tushar Kanti Maiti 《Cell death & disease》2022,13(6)
Nutrient surplus and consequent free fatty acid accumulation in the liver cause hepatosteatosis. The exposure of free fatty acids to cultured hepatocyte and hepatocellular carcinoma cell lines induces cellular stress, organelle adaptation, and subsequent cell death. Despite many studies, the mechanism associated with lipotoxicity and subsequent cell death still remains poorly understood. Here, we have used the proteomics approach to circumvent the mechanism for lipotoxicity using hepatocellular carcinoma cells as a model. Our quantitative proteomics data revealed that ectopic lipids accumulation in cells severely affects the ubiquitin-proteasomal system. The palmitic acid (PA) partially lowered the expression of deubiquitinating enzyme USP7 which subsequently destabilizes p53 and promotes mitotic entry of cells. Our global phosphoproteomics analysis also provides strong evidence of an altered cell cycle checkpoint proteins’ expression that abrogates early G2/M checkpoints recovery with damaged DNA and induced mitotic catastrophe leading to hepatocyte death. We observe that palmitic acid prefers apoptosis-inducing factor (AIF) mediated cell death by depolarizing mitochondria and translocating AIF to the nucleus. In summary, the present study provides evidence of PA-induced hepatocellular death mediated by deubiquitinase USP7 downregulation and subsequent mitotic catastrophe.Subject terms: Apoptosis, Protein-protein interaction networks 相似文献
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本实验探讨冷冻和传统中药炮制方法处理的九香虫对胃癌细胞增殖的影响及九香虫抑癌活性组分的体内分布。体外培养人胃癌SGC-7901细胞,采用四甲基偶氮唑盐比色法(MTT法)观察不同方法处理的九香虫各组分水溶液对SGC-7901细胞的体外抑制作用。结果发现,炮制九香虫蛋白浓度为50和100mg·L~(-1)时作用48h对SGC-7901细胞生长具有抑制作用,抑制率分别为13.45%和14.68%,而浓度达到200和400mg·L~(-1)时对SGC-7901细胞生长具有促进作用,抑制率为-7.94%和-82.50%;冷冻处理下九香虫不同浓度对SGC-7901细胞生长具有显著的抑制作用,该处理组蛋白浓度为50、100、200和400mg·L-1时抑制率分别为0.49%,3.82%,4.42%,39.33%。选取九香虫整虫及分解后的各部位处理组最大作用浓度比较,增殖抑制率为血淋巴腹部整虫头部。因此,冷冻处理的九香虫对胃癌细胞抑制率更高,且在该条件下九香虫的抑癌活性组分主要分布于血淋巴和腹部。 相似文献
47.
Catherine L. Scott S. Kwasniewski Stig Falk-Petersen John R. Sargent 《Polar Biology》2000,23(7):510-516
Stage IV and V copepodites were the dominant forms of Calanus finmarchicus, C. glacialis and C. hyperboreus in Kongsfjorden in late September 1997. Stage IV and V copepodites of C. glacialis and C. hyperboreus were rich in lipid, largely wax esters, and were well fitted to overwinter. Stage IV copepodites of C. finmarchicus were also rich in wax esters, but stage V copepodites of C. finmarchicus were less wax ester-rich. Large size increments between stage IV and V copepodites and between stage V copepodites and females
were noted in C. finmarchicus. A very large increment between stage IV and V copepodites was noted for C. glacialis but the size difference between stage V copepodites and females was very small in this species. Particularly large increments
were noted between stage IV and V copepodites of C. hyperboreus and also between stage V copepodites and females of this species. The very large, wax ester-rich C. hyperboreus is well adapted to survive the most extreme variations in the Arctic, in Arctic basin waters, whereas the smaller, wax ester-rich
C. glacialis is adapted to survive less extreme Arctic variations, as in Arctic shelf waters. The smallest of the three, C. finmarchicus, is best adapted to survive the more predictable waters of the North Atlantic and the Barents Sea.
Accepted: 3 January 2000 相似文献
48.
Ivana Momčilović Dragoljub Grubišić Milan Kojić Mirjana Nešković 《Plant Cell, Tissue and Organ Culture》1997,50(1):1-6
Shoots of micropropagated Gentiana acaulis, G. cruciata, G. lutea, and G. purpurea were inoculated with suspensions of Agrobacterium
rhizogenes cells, strains ATCC 15834 or A4M70GUS. Adventitious roots appeared at the sites of inoculation in all 4 species.
Root tips were excised and cultured on growth regulator-free media for 2-6 years. They exhibited very high branching and plagiotropism.
Spontaneous bud initiation occurred in roots of G. cruciata. Roots of G. lutea, G. acaulis and G. purpurea were cultured on
media with high kinetin concentration, which induced the formation of friable callus tissues. Only in G. purpurea were these
calluses organogenic. Regenerated shoots of G. cruciata and G. purpurea gave rise to plants, that displayed the typical phenotypes
of A. rhizogenes-transformed plants: short internodes and rolled leaves. In the roots of G. acaulis and G. cruciata, transformed
with A. rhizogenes A4M70GUS, a positive reaction with X-gluc indicated the activity of β-glucuronidase. The DNA extracted
from hairy roots and from the roots of transgenic plants hybridized with the appropriate genomic probes in Southern blotting.
This is taken as evidence of the stable genetic transformation in the 4 Gentiana species.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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dsRNA-mediated resistance to Beet Necrotic Yellow Vein Virus infections in sugar beet (Beta vulgaris L. ssp. vulgaris) 总被引:1,自引:0,他引:1
Britt-Louise Lennefors Eugene I. Savenkov Jan Bensefelt Elisabeth Wremerth-Weich Petra van Roggen Stig Tuvesson Jari P. T. Valkonen Jan Gielen 《Molecular breeding : new strategies in plant improvement》2006,18(4):313-325
Rhizomania, one of the most devastating diseases in sugar beet, is caused by Beet Necrotic Yellow Vein Virus (BNYVV) belonging to the genus Benyvirus. Use of sugar beet varieties with resistance to BNYVV is generally considered as the only way to maintain a profitable yield on rhizomania-infested fields. As an alternative to natural resistance, we explored the transgenic expression of viral dsRNA for engineering resistance to rhizomania. Transgenic plants expressing an inverted repeat of a 0.4 kb fragment derived from the BNYVV replicase gene displayed high levels of resistance against different genetic strains of BNYVV when inoculated using the natural vector, Polymyxa betae. The resistance was maintained under high infection pressures and over prolonged growing periods in the greenhouse as well as in the field. Resistant plants accumulated extremely low amounts of transgene mRNA and high amounts of the corresponding siRNA in the roots, illustrative of RNA silencing as the underlying mechanism. The transgenic resistance compared very favourably to natural sources of resistance to rhizomania and thus offers an attractive alternative for breeding resistant sugar beet varieties. 相似文献