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61.
Kristf Kdr Viktria Juhsz Anna Fldes Rbert Rcz Yan Zhang Heike Lchli Erzsbet Kat Lszl Kles Martin C. Steward Pamela DenBesten Gbor Varga kos Zsembery 《International journal of molecular sciences》2021,22(8)
TRPM7 plays an important role in cellular Ca2+, Zn2+ and Mg2+ homeostasis. TRPM7 channels are abundantly expressed in ameloblasts and, in the absence of TRPM7, dental enamel is hypomineralized. The potential role of TRPM7 channels in Ca2+ transport during amelogenesis was investigated in the HAT-7 rat ameloblast cell line. The cells showed strong TRPM7 mRNA and protein expression. Characteristic TRPM7 transmembrane currents were observed, which increased in the absence of intracellular Mg2+ ([Mg2+]i), were reduced by elevated [Mg2+]i, and were inhibited by the TRPM7 inhibitors NS8593 and FTY720. Mibefradil evoked similar currents, which were suppressed by elevated [Mg2+]i, reducing extracellular pH stimulated transmembrane currents, which were inhibited by FTY720. Naltriben and mibefradil both evoked Ca2+ influx, which was further enhanced by the acidic intracellular conditions. The SOCE inhibitor BTP2 blocked Ca2+ entry induced by naltriben but not by mibefradil. Thus, in HAT-7 cells, TRPM7 may serves both as a potential modulator of Orai-dependent Ca2+ uptake and as an independent Ca2+ entry pathway sensitive to pH. Therefore, TRPM7 may contribute directly to transepithelial Ca2+ transport in amelogenesis. 相似文献
62.
Kevin Munoz Samiksha Wasnik Amir Abdipour Hongzheng Bi Sean M. Wilson Xiaolei Tang Mahdis Ghahramanpouri David J. Baylink 《International journal of molecular sciences》2021,22(10)
Acute lung injury (ALI) afflicts approximately 200,000 patients annually and has a 40% mortality rate. The COVID-19 pandemic has massively increased the rate of ALI incidence. The pathogenesis of ALI involves tissue damage from invading microbes and, in severe cases, the overexpression of inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β). This study aimed to develop a therapy to normalize the excess production of inflammatory cytokines and promote tissue repair in the lipopolysaccharide (LPS)-induced ALI. Based on our previous studies, we tested the insulin-like growth factor I (IGF-I) and BTP-2 therapies. IGF-I was selected, because we and others have shown that elevated inflammatory cytokines suppress the expression of growth hormone receptors in the liver, leading to a decrease in the circulating IGF-I. IGF-I is a growth factor that increases vascular protection, enhances tissue repair, and decreases pro-inflammatory cytokines. It is also required to produce anti-inflammatory 1,25-dihydroxyvitamin D. BTP-2, an inhibitor of cytosolic calcium, was used to suppress the LPS-induced increase in cytosolic calcium, which otherwise leads to an increase in proinflammatory cytokines. We showed that LPS increased the expression of the primary inflammatory mediators such as toll like receptor-4 (TLR-4), IL-1β, interleukin-17 (IL-17), TNF-α, and interferon-γ (IFN-γ), which were normalized by the IGF-I + BTP-2 dual therapy in the lungs, along with improved vascular gene expression markers. The histologic lung injury score was markedly elevated by LPS and reduced to normal by the combination therapy. In conclusion, the LPS-induced increases in inflammatory cytokines, vascular injuries, and lung injuries were all improved by IGF-I + BTP-2 combination therapy. 相似文献
63.
Josephine Eskaf William J. Cleveland Matthias L. Riess 《International journal of molecular sciences》2021,22(9)
Myocardial infarction is a leading cause for morbidity and mortality worldwide. The only viable treatment for the ischemic insult is timely reperfusion, which further exacerbates myocardial injury. Maintaining mitochondrial function is crucial in preserving cardiomyocyte function in ischemia reperfusion (IR) injury. Poloxamer (P) 188 has been shown to improve cardiac IR injury by improving cellular and mitochondrial function. The aim of this study was to show if P188 postconditioning has direct protective effects on mitochondrial function in the heart. Langendorff prepared rat hearts were subjected to IR injury ex-vivo and reperfused for 10 min with 1 mM P188 vs. vehicle. Cardiac mitochondria were isolated with 1 mM P188 vs. 1 mM polyethylene glycol (PEG) vs. vehicle by differential centrifugation. Mitochondrial function was assessed by adenosine triphosphate synthesis, oxygen consumption, and calcium retention capacity. Mitochondrial function decreased significantly after ischemia and showed mild improvement with reperfusion. P188 did not improve mitochondrial function in the ex-vivo heart, and neither further P188 nor PEG induced direct mitochondrial protection after IR injury in this model. 相似文献
64.
磷石膏的综合利用对保护环境、促进企业可持续健康发展具有重要意义,但是磷石膏中的磷、氟、二氧化硅等杂质影响其利用。针对云南磷石膏中二氧化硅含量高的问题,采用正浮选工艺开展了磷石膏提质降杂的实验研究。通过单因素条件实验获得了合适的工艺参数:浮选温度为15 ℃、矿浆pH为2、十二胺用量为300 g/t。在此条件下,进行了“一粗二精”的正浮选开路流程实验,获得了二水石膏(CaSO4·2H2O)质量分数为97.5%、二氧化硅质量分数为1.17%的精矿,所得精矿达到了GB/T 23456—2018《磷石膏》一级品指标的要求;二水石膏回收率为98.58%、二氧化硅去除率为92.23%。通过正浮选不仅成功实现了二水石膏和二氧化硅的有效分离,而且磷石膏中的水溶磷和水溶氟也得到了有效去除,从而提高了磷石膏的品质。 相似文献
65.
针对冷冻法硝酸磷肥副产粗硝钙液中的磷进入滤渣难以回收利用导致硝酸磷肥装置产能低、胶磷矿富集技术浸取工段氨逃逸率低致使浸取液中硝酸铵含量高造成下游无法使用的问题,开展了粗硝钙液用于磷矿脱镁的研究。实验方法及最优反应条件:原矿经破碎、煅烧(煅烧温度为900~1 100 ℃,煅烧时间为1.5~3.0 h),用粗硝钙液浸取,利用粗硝钙液的热能和化学反应热控制反应温度为60~70 ℃(不需加热,节省了蒸汽消耗),反应pH为4.5~6.5,反应过程中无磷析出。在此条件下制取的磷精矿中五氧化二磷质量分数≥35%、氧化镁质量分数≤1.0%,磷回收率为100.49%~100.60%。将制取的磷精矿进行酸解,提高了酸不溶物的分离效率,可满足下游生产白色硝酸磷肥对原料的要求,副产的浸取液可用于生产氨基酸液体肥和中量元素营养母粒。该方法无尾矿产生,绿色环保,为磷矿的高效利用提供了新的研究思路。 相似文献
66.
利用硫磺、碳等还原硫酸法钛白粉生产副产物钛白石膏是处理钛白石膏堆放问题的方法之一。针对硫磺在回转窑分解钛白石膏制硫酸和氧化钙的过程存在时间长、硫磺用量大、硫化钙产量不高等问题,提出了以钛白石膏为原料利用酸浸法去除铁杂质后,利用硫磺为还原剂将石膏在气固竖式反应器中煅烧生成硫化钙和二氧化硫,前者再与硫酸钙煅烧制得氧化钙和二氧化硫,得到的氧化钙可以中和废酸和废水,产生的二氧化硫用来制硫酸的方法。先利用反应热力学计算软件HSC分析确定实验方案,分别在流态化实验(800 ℃,保温40 min)和煅烧实验(1 100℃,保温1.5 h)后得到硫化钙转化率与氧化钙纯度均达到90%左右。再利用Aspen软件模拟了工艺流程,模拟出二氧化硫体积分数可达12.09%,满足制硫酸的需求。硫酸生产成本估算为263.9元/t,具有较大的市场前景。 相似文献
67.
燃煤锅炉污染物超低排放标准对电厂脱硫和脱硝系统提出了更高的要求。CaO作为脱硫剂可以实现循环流化床锅炉烟气中SO2的高效脱除,焦炭作为还原剂直接还原NO,同时CaO的存在对焦炭还原NO起催化作用,可以实现燃煤烟气中SO2/NO的联合脱除。为了探究连续温度变化对CaO/生物质焦联合脱硫脱硝性能的影响,在钙循环捕集CO2技术背景下,研究了等速升温流态化下CaO/生物质焦的SO2/NO联合脱除特性。探究了烟气中O2和CO2对CaO/椰壳焦脱除SO2/NO的影响。结果表明,O2通过对椰壳焦表面碳原子的活化作用降低了异相还原NO温度,在300~950℃等速升温过程中CaO/椰壳焦的NO脱除效率逐渐增加,780℃以上能实现100%脱硝。O2也提高了CaO/椰壳焦的脱硫效率。CO2与CaO的碳酸化反应以及与椰壳焦的气化反应对同时脱除SO2/NO有明显抑制作用。O2和CO2共同作用下,在500~800℃内CaO/椰壳焦的脱硝效率随温度升高而增加,脱硫效率先降低后升高。NO促进了CaO/椰壳焦脱除SO2,而SO2对脱硝有抑制作用。800℃时CaO/椰壳焦同时脱除SO2和NO的效率分别为97.7%和93.9%。 相似文献
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70.
为研究LF-RH精炼工艺生产Q690钢时不同钙处理时机下夹杂物特征的变化,开展工业试验对RH精炼前后钙处理炉次取样进行定量分析对比。钙处理后夹杂物中CaO质量分数持续增加,CaS质量分数瞬态增加,夹杂物熔点降低。RH精炼前钙处理炉次中,RH精炼过程夹杂物的成分接近低熔点区,结束时夹杂物数量密度和面积分数分别为15个/mm2和0.01%。RH精炼后钙处理炉次中,RH精炼过程夹杂物依旧为高熔点Al2O3-MgO类型,结束时夹杂物数量密度和面积分数分别降至1个/mm2和0.002 5%。RH精炼前钙处理会使RH精炼过程夹杂物熔点以及夹杂物与钢液间的接触角降低,导致夹杂物去除驱动力降低,从而抑制夹杂物的去除。因此LF-RH精炼工艺生产铝脱氧钢时,为提高精炼过程钢中非金属夹杂物的去除效率,应在RH精炼后进行钙处理操作。 相似文献