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991.
Alessandra Bosutti Barbara Dapas Gabriele Grassi Rossana Bussani Fabrizio Zanconati Fabiola Giudici Cristina Bottin Nicola Pavan Carlo Trombetta Bruna Scaggiante 《International journal of molecular sciences》2022,23(8)
Although the eukaryotic elongation factor eEF1A1 plays a role in various tumours, there is little information on its prognosis/therapeutic value in prostate carcinoma. In high-grade and castration-resistant prostate carcinoma (CRPC), the identification of novel therapeutic markers/targets remains a priority. The expression of eEF1A1 protein was determined in formalin-fixed, paraffin-embedded prostate cancer and hyperplasia tissue by IHC. The role of eEF1A1 was investigated in a cellular model using a DNA aptamer (GT75) we previously developed. We used the aggressive CRPC cancer PC-3 and non-tumourigenic PZHPV-7 lines. Cytotoxicity was measured by the MTS assay and eEF1A1 protein levels by in-cell Western assays. The mRNA levels of eEF1A1 were measured by qPCR and ddPCR. Higher expression of eEF1A1 was found in Gleason 7–8 compared with 4–6 tissues (Gleason ≥ 7, 87% versus Gleason ≤ 6, 54%; p = 0.033). Patients with a high expression of eEF1A1 had a worse clinical outcome. In PC-3, but not in PZHPV-7, GT75 decreased cell viability and increased autophagy and cell detachment. In PC-3 cells, but not in PZHPV-7, GT75 mainly co-localised with the fraction of eEF1A1 bound to actin. Overexpression of the eEF1A1 protein can identify aggressive forms of prostate cancer. The targeting of eEF1A1 by GT75 impaired cell viability in PC-3 cancer cells but not in PZHPV-7 non-tumourigenic cells, indicating a specific role for the protein in cancer survival. The eEF1A1–actin complexes appear to be critical for the viability of PC-3 cancer cells, suggesting that eEF1A1 may be an attractive target for therapeutic strategies in advanced forms of prostate cancer. 相似文献
992.
The effect of zeolite A supplementation in the dry period on periparturient calcium,phosphorus, and magnesium homeostasis 总被引:2,自引:0,他引:2
One potential way of preventing parturient hypocalcemia in the dairy cow is to feed dry cow rations very low in calcium (<20 g/d); but, because it is difficult to formulate rations sufficiently low in calcium, this principle has been almost abandoned. Recent studies have shown, however, that it is possible to prevent milk fever, as well as subclinical hypocalcemia, by supplementing the dry cow ration with sodium aluminium silicate (zeolite A), which has the capacity to bind calcium. The aim of this study was to further evaluate the effect, if any, of such supplementation on other blood constituents, feed intake, and milk production in the subsequent lactation. A total of 31 pregnant dry cows about to enter their third or later lactation were assigned as experimental or control cows according to parity and expected date of calving. The experimental cows received 1.4 kg of zeolite pellets per d (0.7 kg of pure zeolite A) for the last 2 wk of pregnancy. Blood samples were drawn from all cows 1 wk before the expected date of calving, at calving, at d 1 and 2 after calving, and 1 wk after calving. Additionally, a urine sample was drawn 1 wk before the expected date of calving. Zeolite supplementation significantly increased the plasma calcium level on the day of calving, whereas plasma magnesium as well as inorganic phosphate was suppressed. Serum 1,25(OH)2D was significantly increased 1 wk before the expected date of calving among the experimental cows, whereas there was no difference in the urinary excretion of the bone metabolite deoxypyridinoline between the two groups. Feed intake was decreased among the zeolite-treated cows during the last 2 wk of pregnancy. No effect was observed on milk yield, milk fat, and milk protein in the subsequent lactation. The mechanisms and interactions involved in zeolite supplementation are discussed in relation to the observed improvement in parturient calcium homeostasis and to the observed depression in blood magnesium and inorganic phosphate. 相似文献
993.
对从红茶菌中分离出的菌株(Gluconacetobacter sp.A4)进行研究,分别以红茶、荷叶、荷叶与山楂、荷叶与决明子为底物进行发酵,以传统红茶菌混合发酵为对照,通过对其产物D-葡萄糖二酸-1,4-内酯含量等指标的测定来评价发酵效果,同时研究了不同底物红茶菌发酵液对消化酶活性的影响。结果表明:在30℃、发酵8 d的情况下,以荷叶山楂A4发酵液发酵最为充分,其次为红茶A4发酵液。红茶A4发酵液的D-葡萄糖二酸-1,4-内酯(DSL)生成量最高。各发酵液对脂肪酶的抑制作用以红茶A4发酵液抑制作用最强,荷叶A4发酵液次之;对α-淀粉酶的抑制作用,以荷叶决明子A4发酵液的抑制率最高,红茶A4发酵液次之。不同红茶菌发酵液对消化酶的活性具有抑制作用,为其减肥机理的研究以及功能饮料的开发奠定基础。 相似文献
994.
真核细胞中大部分膜融合过程由SNARE蛋白介导,但其功能和调节机制尚未完全清楚。酵母孢子形成是研究囊泡融合机制包括SNARE蛋白的理想模型系统。在该过程中涉及t-SNARE蛋白Sso1,它是突触囊泡融合所需蛋白syntaxin 1A的同源物,两者SNARE区域有51%的同源性。尽管如此,将SSO1的SNARE区域完全替换成syntaxin 1A,而构建的嵌合体却无法回补sso1△突变的产孢缺陷。为了确定哪些残基为Sso1功能所必须,作者进行了嵌合体和突变分析,发现Sso1/syntaxin 1A嵌合体中syntaxin 1A的SNARE区域的220位丙氨酸换成谷氨酸后获得产孢功能。另外,Sso1发生相应的突变-218位谷氨酸突变成丙氨酸后失去其功能。因此,218位谷氨酸残基为Sso1产孢功能所必须。 相似文献
995.
996.
葡萄酒作为一种酒精饮料,对众多国家的经济贡献是显著的。然而,该商品容易被某些真菌产生的霉菌毒素所污染,其中最受关注的是产赭曲霉毒素A(ochratoxin A, OTA)的炭黑曲霉。赭曲霉毒素A是葡萄酒中主要存在的霉菌毒素,严重影响着人类的健康。因此,葡萄酒的风险监测和暴露研究至关重要。本研究重点阐述了OTA的生物合成途径及其调控机制,同时,介绍了酿酒过程中OTA的变化情况以及控制和检测OTA的方法,旨在为保证葡萄酒产品的质量安全提供一些理论参考。 相似文献
997.
介绍了立缫机技改为SFD5 0 7A型自动缫丝机的机型特点和生产实绩 ,以及在设备管理、操作管理、成本管理方面的一些体会。 相似文献
998.
厌氧序批式反应器(ASBR)的六大优点 总被引:4,自引:0,他引:4
分析了厌氧序批式反应器(ASBR)的六大优点,与连续流厌氧反应器相比,ASBR构造简单、投资省,生物絮凝和固液分离效果好,水头损失小、动力费用低,生化反应推动力大,可形成以甲烷八叠球菌为优势茵的颗粒污泥,处理高浓度有机废水时对碱度的需求量少,运行费用低。 相似文献
999.
This work presents an experimental evaluation, from an energy analysis point of view, for two of the most used inter-stage systems in two-stage vapour compression cycles driven by compound compressors: the direct liquid injection and subcooler systems. The evaluation, considers the two-stage cycle with no intermediate systems as reference cycle and was performed on a plant, driven by a compound compressor using the refrigerant R404A for an evaporating temperature range of −36 to −20 °C and for a condensing temperature range of 30–47 °C. The analysis of the results shows that the inter-stage systems determine the performance of the energy parameters, which are discussed in the paper. The configuration yielding the best results was the two-stage compression cycle with subcooler, since the cooling capacity and COP values for this configuration were the highest. Conversely, the two-stage compression cycle working with direct liquid injection showed lower performance from an energy point of view, though this configuration allows a substantial reduction of the discharge temperature. 相似文献
1000.