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971.
972.
973.
A 104-kD protein was coimmunoprecipitated with the estrogen receptor from the flowtrough of a phosphocellulose chromatography of MCF-7 cell nuclear extract. mAbs to this protein identified several cDNA clones coding for the human 104-kD major vault protein. Vaults are large ribonucleoprotein particles of unknown function present in all eukaryotic cells. They have a complex morphology, including several small molecules of RNA, but a single protein species, the major vault protein, accounts for >70% of their mass. Their shape is reminiscent of the nucleopore central plug, but no proteins of known function have been described to interact with them. Western blot analysis of vaults purified on sucrose gradient showed the presence of estrogen receptor co-migrating with the vault peak. The AER317 antibody to estrogen receptor coimmunoprecipitated the major vault protein and the vault RNA also in the 20,000 g supernatant fraction. Reconstitution experiments of estrogen receptor fragments with the major vault protein mapped the site of the interaction between amino acids 241 and 280 of human estrogen receptor, where the nuclear localization signal sequences are located. Estradiol treatment of cells increased the amount of major vault protein present in the nuclear extract and coimmunoprecipitated with estrogen receptor, whereas the anti-estrogen ICI182,780 had no effect. The hormone-dependent interaction of vaults with estrogen receptor was reproducible in vitro and was prevented by sodium molybdate. Antibodies to progesterone and glucocorticoid receptors were able to coimmunoprecipitate the major vault protein. The association of nuclear receptors with vaults could be related to their intracellular traffic.  相似文献   
974.
Metabolic patterns and insulin responsiveness of enlarging fat cells   总被引:7,自引:0,他引:7  
The rate and pattern of glucose metabolism, basal lipolysis, and intracellular concentration of free fatty acids were determined in isolated epididymal fat cell preparations (mean volume 30-800 pl) from rats on the basis of fat cell number and in relation to the cell volume. The effects of increasing glucose concentrations in the medium and of insulin on the cellular metabolic activities were compared. Expanding fat cell volume correlated positively and significantly (P < 0.001) with the synthesis of glyceride glycerol from glucose (correlation coefficient, r = 0.919), with rates of basal lipolysis (r = 0.663), and with intracellular free fatty acid accumulation (r = 0.796); it correlated negatively and significantly with glucose conversion to glyceride fatty acids (r = -0.814, P < 0.01). The differences in patterns of glucose metabolism and basal lipolysis between small (<100 pl) and large (>400 pl) fat cells were not modified by insulin or by increments in glucose concentration. The results indicate that the reduced capacity of the large fat cells to respond to insulin cannot be attributed solely to a limited capacity of the cells to take up and metabolize increasing amounts of glucose. The acquired unresponsiveness of the large cells to insulin may result from an alteration in the mechanism of action of insulin and may be related to an intracellular metabolic derangement with increased basal lipolysis, free fatty acid accumulation, and accelerated glyceride synthesis resulting from the accumulation of triglyceride.  相似文献   
975.
The sterol composition of 17 red algae has been determined. Only C-27 sterols have been found in substantial amounts; details of the structural elucidation of liagosterol (cholesta-5,23-diene-3β,25-diol) are given. The possible taxonomic significance of the sterol distribution is briefly discussed.  相似文献   
976.
A screening of 51 ligninolytic strains of fungi to examine their ability to decolorized phenolic industrial effluent was carried out. The selection showed thatLentinus edodes (UEC-2019) strain removed 73% of colour in 5 days, without any additional carbon sources. Under these conditions,L. edodes was more efficient than the knownPhanerochaete chrysosporium (BKM-F-1767) strain (e.g. COD reductions were 60% and 26%, respectively).  相似文献   
977.
Growth, intrácellular free amino acid pools and photosynthetic and respiratory activities in nutrient sufficient cells and in N- K- and P-limited cells of Cyanidium caldarium (Tilden) Geitler, and responses to nutrient resupply were investigated. Addition of ammonium to N-limited cells and of phosphate to P-limited cells resulted in a stimulation of dark respiration and in a decrease in photosynthetic oxygen evolution. Addition of K to K-limited cells had no effect on rates of photosynthesis and respiration. Nutrient limited cells and sufficient cells exhibited different free amino acid profiles. Upon resupply of ammonium to N-limited cells levels of glutamine, citrulline, arginine, alanine, and serine increased. Also the levels of δ-aminolevulinic acid (δ-ALA) and putrescine increased notably. On adding phosphate to P-limited cells the level of glutamate decreased significantly whereas the level of alanine increased and the concentrations of other amino acids remained unaffected. On adding potassium to K-limited cells there was an increase in glutamate and citrulline concentrations, and a decrease in putrescine concentration, whereas concentrations of arginine and alanine remained at the very high levels observed already before addition. Resuspension of N- and K-limited cells in a complete growth only after 25-30h. In P-limited cells resumption of growth in complete medium occurred progressively and reached the maximum rate 30h later. P-, K- and N- limited cells resuspended into sufficient media showed different rates of ammonium and phosphate assimilation. The pattern of recovery from nutrient limitation is discussed according to the cellular role fulfilled by the nutrient which was growth rate-limiting.  相似文献   
978.

Objectives

We evaluate whether the thrombus aspiration (TA) before primary percutaneous coronary intervention (PPCI) may improve STEMI outcomes in hyperglycemic patients.

Background

The management of hyperglycemic patients during STEMI is unclear.

Methods

We undertook an observational cohort study of 3166 first STEMI. Patients were grouped on the basis of whether they received TA or not. Moreover, among these patients we selected a subgroup of STEMI patients with hyperglycemia during the event (glycaemia?>?140 mg/dl). The endpoint at 1 year included all-cause mortality, cardiac mortality and re-hospitalization for coronary disease, heart failure and stroke.

Results

One-thousand STEMI patients undergoing PPCI to plus TA (TA-group) and 1504 STEMI patients treated with PPCI alone (no-TA group) completed the study. In overall study-population, Kaplan–Meier-analysis demonstrated no significant difference in mortality rates between patients with and without TA (P?=?0.065). After multivariate Cox-analysis (HR: 0.94, 95% CI 0.641–1.383) and the addition of propensity matching (HR: 0.86 95% CI 0.412–1.798) TA was still not associated with decreased mortality. By contrast, in hyperglycemic subgroup STEMI patients (TA-group, n?=?331; no-TA group, n?=?566), Kaplan–Meier-analysis demonstrated a significantly lower mortality (P?=?0.019) in TA-group than the no-TA group. After multivariate Cox-analysis (HR: 0.64, 95% CI 0.379–0.963) and the addition of propensity matching (HR: 0.54, 95% CI 0.294–0.984) TA was still associated with decreased mortality.

Conclusions

TA was not associated with lower mortality in PPCI for STEMI when used in our large all-comer cohort. Conversely, TA during PPCI for STEMI reduces clinical outcomes in hyperglycemic patients.Trial registration NCT02817542. 25th, June 2016
  相似文献   
979.
Although the ability ofAureobasidium pullulans BH-I-ATCC 34621 to cause paint deterioration during its growth on wood has been reported, the mechanism by which paint degradation occurred was unclear. Evidence now indicates that co-metabolism of acrylic, resins in the paint is the cause of paint deterioration byA. pullulans.  相似文献   
980.
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