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991.
BackgroundHyperphosphatemia and anemia, which are common complications of chronic kidney disease (CKD), can independently contribute to cardiovascular events. Several previous studies have found that the iron-based phosphate binder, ferric citrate (FC), could be beneficial to both hyperphosphatemia and anemia.MethodsRelevant literature from PUBMED, EMBASE, the Cochrane Central Register of Controlled Trials (CCRCT) and MEDLINE databases were searched up to 21 February 2022, in order to conduct a meta-analysis to investigate the efficacy, safety and economic benefits of ferric citrate treatment in CKD patients with hyperphosphatemia and anemia. The meta-analysis was conducted independently by two reviewers using the RevMan software (version 5.3).ResultsIn total, this study included 16 randomized clinical trials (RCT) involving 1754 participants. The meta-analysis showed that ferric citrate could significantly reduce the serum phosphorus in CKD patients compared to the placebo control groups (MD −1.76 mg/dL, 95% CI (−2.78, −0.75); p = 0.0007). In contrast, the difference between ferric citrate treatment and active controls, such as non-iron-based phosphate binders, sevelamer, calcium carbonate, lanthanum carbonate and sodium ferrous citrate, was not statistically significant (MD − 0.09 mg/dL, 95% CI (−0.35, 0.17); p = 0.51). However, ferric citrate could effectively improve hemoglobin levels when compared to the active drug (MD 0.43 g/dL, 95% CI (0.04, 0.82); p = 0.03) and placebo groups (MD 0.39 g/dL, 95% CI (0.04, 0.73); p = 0.03). According to eight studies, ferric citrate was found to be cost-effective treatment in comparison to control drugs. Most of the adverse events (AE) following ferric citrate treatment were mild at most.ConclusionCollectively, our review suggests that iron-based phosphate binder, ferric citrate is an effective and safe treatment option for CKD patients with hyperphosphatemia and anemia. More importantly, this alternative treatment may also less expensive. Nevertheless, more scientific studies are warranted to validate our findings.  相似文献   
992.
993.
血管紧张素Ⅱ受体阻滞剂(ARB)通过阻滞1型血管紧张素Ⅱ受体(AT1受体)降低血压、逆转血管重构,激活2型血管紧张素Ⅱ受体(AT2受体)以提高血管紧张素Ⅱ(AngⅡ)水平扩张血管、抗增殖及调脂.进一步了解ARB在神经保护中的作用机制,可为临床治疗缺血性卒中提供新的思路.  相似文献   
994.
目的:通过超高速细胞分选平台结合cDNA microarray技术,筛查宫颈癌细胞可能潜在的分子标志物。方法:采用MoFlo XDP型超高速细胞分选平台纯化细胞膜表面表达CD38和不表达CD38的宫颈癌细胞,利用RNAlater技术得到cDNA microarray实验所需RNA,然后进行基因芯片分析。结果:利用MoFlo XDP型超高速细胞分选平台可以获得纯度为99.0%以上的CD38阳性表达宫颈癌细胞。结论:cDNA microarray分析发现了RORA、PLIN4、AUTS2、IFITM1等宫颈癌细胞潜在分子标志物,为宫颈癌研究提供了新的技术方法。  相似文献   
995.
Five previously undescribed epoxy octa-hydronaphthalene polyketides, altereporenes A–E (1–5) were isolated from rice culture of the endophytic fungus Alternaria sp. YUD20002 derived from the tubers of Solanum tuberosum. Their structures were determined on the basis of comprehensive spectroscopic analyses, while the absolute configurations were elucidated by the comparison of experimental and calculated specific rotations. Meanwhile, the antimicrobial, cytotoxic, anti-inflammatory and acetylcholinesterase inhibitory activities of compounds 1–5 were also investigated.

Five previously undescribed epoxy octa-hydronaphthalene polyketides, altereporenes A–E (1–5) were isolated from rice culture of the endophytic fungus Alternaria sp. YUD20002 derived from the tubers of Solanum tuberosum.  相似文献   
996.
Efficient catalysts for the electroreduction of N2 to NH3 are of paramount importance for sustainable ammonia production. Recently, it was reported that NbSe2 nanosheets exhibit an excellent catalytic activity for nitrogen reduction under ambient conditions. However, existing theoretical calculations suggested an overpotential over 3.0 V, which is too high to interpret the experimental observations. To reveal the underlying mechanism of the high catalytic activity, in this work, we assessed NbSe2 edges with different chirality and Se vacancies by using first principles calculations. Our results show that N2 can be efficiently reduced to NH3 on a pristine zigzag edge via the enzymatic pathway with an overpotential of 0.45 V. Electronic structure analysis demonstrates that the N2 molecule is activated by the back-donation mechanism. The efficient tuning of the local chemical environments by edge chirality provides a promising approach for catalyst design.

The zigzag edge of the NbSe2 monolayer exhibits an overpotential as low as 0.45 V along the enzymatic pathway.  相似文献   
997.
Bellidifolin (BEL), a xanthone compound, has significant therapeutic effectiveness in cardiac diseases such as arrhythmias. However, BEL is limited in clinical applications by its hydrophobicity. In this work, we used BEL as the active pharmaceutical ingredient (API), and polyethylene glycol 15-hydroxy stearate (Kolliphor HS15) as the carrier to prepare BEL nano-micelles by a solvent-volatilization method. According to an analysis by differential scanning calorimetry (DSC), BEL was successfully encapsulated in HS15 as BEL nano-micelles with a 90% encapsulation rate, and particle size was 12.60 ± 0.074 nm in the shape of a sphere and electric potential was −4.76 ± 4.47 mV with good stability and sustained release characteristics. In addition, compared with free drugs, these nano-micelles can increase cellular uptake capacity, inhibit the proliferation of human cardiac fibroblasts, and down-regulate the expression of Smad-2, α-SMA, Collagen I, and Collagen III proteins in myocardial cells to improve myocardial fibrosis. In conclusion, the BEL nano-micelles can provide a new way for the theoretical basis for the clinical application of anti-cardiac fibrosis.

Bellidifolin (BEL), a xanthone compound, has significant therapeutic effectiveness in cardiac diseases such as arrhythmias.  相似文献   
998.
BackgroundThe pathogenesis of chronic migraine remains unresolved. Recent studies have affirmed the contribution of GLUA1-containing AMPA receptors to chronic migraine. The dopamine D2 receptor, a member of G protein-coupled receptor superfamily, has been proven to have an analgesic effect on pathological headaches. The present work investigated the exact role of the dopamine D2 receptor in chronic migraine and its effect on GLUA1-containing AMPA receptor trafficking.MethodsA chronic migraine model was established by repeated inflammatory soup stimulation. Mechanical, periorbital, and thermal pain thresholds were assessed by the application of von Frey filaments and radiant heat. The mRNA and protein expression levels of the dopamine D2 receptor were analyzed by qRT‒PCR and western blotting. Colocalization of the dopamine D2 receptor and the GLUA1-containing AMPAR was observed by immunofluorescence. A dopamine D2 receptor agonist (quinpirole) and antagonist (sulpiride), a PI3K inhibitor (LY294002), a PI3K pathway agonist (740YP), and a GLUA1-containing AMPAR antagonist (NASPM) were administered to confirm the effects of the dopamine D2 receptor, the PI3K pathway and GULA1 on central sensitization and the GLUA1-containing AMPAR trafficking. Transmission electron microscopy and Golgi-Cox staining were applied to assess the impact of the dopamine D2 receptor and PI3K pathway on synaptic morphology. Fluo-4-AM was used to clarify the role of the dopamine D2 receptor and PI3K signaling on neuronal calcium influx. The Src family kinase (SFK) inhibitor PP2 was used to explore the effect of Src kinase on GLUA1-containing AMPAR trafficking and the PI3K signaling pathway.ResultsInflammatory soup stimulation significantly reduced pain thresholds in rats, accompanied by an increase in PI3K-P110β subunit expression, loss of dopamine receptor D2 expression, and enhanced GLUA1-containing AMPA receptor trafficking in the trigeminal nucleus caudalis (TNC). The dopamine D2 receptor colocalized with the GLUA1-containing AMPA receptor in the TNC; quinpirole, LY294002, and NASPM alleviated pain hypersensitivity and reduced GLUA1-containing AMPA receptor trafficking in chronic migraine rats. Sulpiride aggravated pain hypersensitivity and enhanced GLUA1 trafficking in CM rats. Importantly, the anti-injury and central sensitization-mitigating effects of quinpirole were reversed by 740YP. Both quinpirole and LY294002 inhibited calcium influx to neurons and modulated the synaptic morphology in the TNC. Additional results suggested that DRD2 may regulate PI3K signaling through Src family kinases.ConclusionModulation of GLUA1-containing AMPA receptor trafficking and central sensitization by the dopamine D2 receptor via the PI3K signaling pathway may contribute to the pathogenesis of chronic migraine in rats, and the dopamine D2 receptor could be a valuable candidate for chronic migraine treatment.Supplementary InformationThe online version contains supplementary material available at 10.1186/s10194-022-01469-x.  相似文献   
999.
Accurate methods for identifying pelvic lymph node metastasis(LNM)of prostate cancer(PCa)prior to surgery are still lacking.We aimed to investigate the predicti...  相似文献   
1000.
目的以健康家兔为实验对象研究抗癌药羟喜树碱的毒性作用与剂量的相关性,为进一步对羟喜树碱毒性作用的防治研究提供参考。方法选择新西兰兔,经耳廓静脉连续推注羟喜树碱14d,观察不同剂量(2.1mg/kg组,1·05mg/kg组,0·52mg/kg组)对家兔免疫功能、肾脏、肝脏和心脏的毒性作用及生化指标的变化。结果三组WBC,RBC,IgG,IgM,AST,CK0·52mg/kg组,LDH2·1mg/kg组均较用药前明显下降(P<0·05和0·01);ALT则显著增高(P<0·01)用药后21d时PLT与LDH1·5mg/kg组较用药前明显下降(P<0·05和0·01)。用药后14,21d时LDH0·52mg/kg组较用药前明显下降(P<0·05和0·01)。结论羟喜树碱可引起家兔明显的肝组织、免疫功能、造血功能的损伤和轻度心脏毒性。但对其损伤机制有待进一步研究。  相似文献   
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