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911.
A thrombus, known as a blood clot, may form within the vascular system of the body and impede blood flow. Thrombosis is the most common underlying pathology of cardiovascular diseases, contributing to high morbidity and mortality. However, the main thrombolytic drugs (urokinase, streptokinase, etc.) have shortcomings, including a short half-life, serious side effects and a lack of targeting, that limit their clinical application. The use of nano-drug delivery systems is expected to address these problems and a variety of approaches, including biological and physical responsive systems, have been explored. In this report, recent advances in the development of targeted nano-drug delivery systems are thoroughly reviewed.  相似文献   
912.
Red deer (Cervus elaphus) blood is widely used as a health product. Mixed culture fermentation improves the flavor and bioavailability of deer blood (DB), and both DB and its enzymatic hydrolysates exhibit anti-fatigue activities in vivo. To elucidate the bioactive ingredients, enzymatic hydrolysates were fractioned into different peptide groups using reversed phase resin chromatography, and then evaluated using an exhaustive swimming mice model to assess swimming time and biochemical parameters. The structures of the bioactive peptides were elucidated by high performance liquid chromatography with tandem mass detection. Thirty-one compounds were identified as glutamine or branched-chain amino acids containing short peptides, of which Val-Ala-Asn, Val-Val-Ser-Ala, Leu(Ile)-Leu(Ile)-Val-Thr, Pro-His-Pro-Thr-Thr, Glu-Val-Ala-Phe and Val-Leu(Ile)-Asp-Ala-Phe are new peptides. The fractions containing glutamine or valine short peptides, Ala-Gln, Val-Gln, Val-Val-Ser-Ala, Val-Leu(Ile)-Ser improved exercise endurance by increasing hepatic glycogen (HG) storage. The peptides group containing Leu(Ile)-Leu(Ile), Asp-Gln, Phe- Leu(Ile), Val-Val-Tyr-Pro contributed to decreased muscle lactic acid (MLA)accumulation and to an increase in HG. The anti-fatigue activities of DB hydrolysates were attributed to the synergistic effects of different types of peptides.  相似文献   
913.
An efficient fluidization process intensification method was proposed to prepare carbon nanotube(CNT)-enhanced high-performance SiO anodes for lithium-ion batte...  相似文献   
914.
Redox homeostasis, as an innate cellular defense mechanism, not only contributes to malignant transformation and metastasis of tumors, but also seriously restricts reactive oxygen species (ROS)-mediated tumor therapies, such as chemotherapy, radiotherapy, photodynamic therapy (PDT), and chemodynamic therapy (CDT). Therefore, the development of the redox dyshomeostasis (RDH) strategy based on nanomaterials chemistry is of great significance for developing highly efficient tumor therapy. This review will firstly introduce the basic definition and function of cellular redox homeostasis and RDH. Subsequently, the current representative progress of the nanomaterial-based RDH strategy for tumor therapy is evaluated, summarized and discussed. This strategy can be categorized into three groups: (1) regulation of oxidizing species; (2) regulation of reducing species and (3) regulation of both of them. Furthermore, the current limitations and potential future directions for this field will be briefly discussed. We expect that this review could attract positive attention in the chemistry, materials science, and biomedicine fields and further promote their interdisciplinary integration.

This review summarizes the current progress of the redox dyshomeostasis (RDH) strategy for tumor therapy. This strategy makes tumor cells more sensitive to current therapy patterns through using nanomaterials to disrupt redox homeostasis.  相似文献   
915.
The cause of liver damage by using black cohosh preparation has been concerned but remains unclear. After a preliminary investigation, the black cohosh medicinal materials sold in the market were adulterated with Asian cohosh (Cimicifuga) without removing the fibrous roots. The safety of Cimicifuga rhizome and fibrous roots is unknown and has not been reported. Therefore, in this paper, the rhizome and fibrous roots of Cimicifuga dahurica (Turcz.) Maxim (C. dahurica) were completely separated, extracted with 70% ethanol, and freeze-dried to obtain crude rhizome extract (RC) and fibrous roots extract (FRC). UHPLC-Q-TOF-MS was used to identify 39 compounds in the rhizome and fibrous roots of Cimicifuga, mainly saponins and phenolic acids. In the L-02 cytotoxicity experiment, the IC50 of fibrous roots (1.26 mg/mL) was slightly lower than that of rhizomes (1.417 mg/mL). In the 90-day sub-chronic toxicity study, the FRC group significantly increased the level of white blood cells, ALP, ALT, AST, BILI and CHOL (p < 0.05); large area of granular degeneration and balloon degeneration occurred in liver tissue; and the expression of p-NF-kB in the nucleus increased in a dose-dependent manner. Overall, Fibrous roots of Cimicifuga are at risk of hepatotoxicity and should be strictly controlled and removed during the processing.  相似文献   
916.
Mohasan  Muhammad  Aqeel  Anas Bin  Lv  Pengyu  Yang  Yantao  Duan  Huiling 《Acta Mechanica Sinica》2021,37(3):447-455
Acta Mechanica Sinica - In this work, we numerically study the impact of a water droplet onto a deep oil pool. Two fluids are immiscible and the viscosity of the pool liquid is changed...  相似文献   
917.
Anticancer treatment is largely affected by the hypoxic tumor microenvironment (TME), which causes the resistance of the tumor to radiotherapy. Combining radiosensitizer compounds and O2 self-enriched moieties is an emerging strategy in hypoxic-tumor treatments. Herein, we engineered GdW10@PDA-CAT (K3Na4H2GdW10O36·2H2O, GdW10, polydopamine, PDA, catalase, CAT) composites as a radiosensitizer for the TME-manipulated enhancement of radiotherapy. In the composites, Gd (Z = 64) and W (Z = 74), as the high Z elements, make X-ray gather in tumor cells, thereby enhancing DNA damage induced by radiation. CAT can convert H2O2 to O2 and H2O to enhance the X-ray effect under hypoxic TME. CAT and PDA modification enhances the biocompatibility of the composites. Our results showed that GdW10@PDA-CAT composites increased the efficiency of radiotherapy in HT29 cells in culture. This polyoxometalates and O2 self-supplement composites provide a promising radiosensitizer for the radiotherapy field.  相似文献   
918.
Lv  Mingyang  Zhang  Xiaogang  Chen  Hua  Zhou  Yicong  Li  Jianmin 《Nonlinear dynamics》2020,99(4):3089-3111
Nonlinear Dynamics - In numbers of industrial fields, many filtering algorithms of industrial signals, mechanism-based modeling methods and control strategies are based on the hypothesis of white...  相似文献   
919.
Compression-induced apoptosis of nucleus pulposus (NP) cells plays a pivotal role in the pathogenesis of intervertebral disc degeneration (IVDD). Recent studies have shown that the dysregulation of mitochondrial fission and fusion is implicated in the pathogenesis of a variety of diseases. However, its role in and regulatory effects on compression-induced apoptosis of NP cells have not yet been fully elucidated. Heat shock protein 70 (HSP70) is a major cytoprotective heat shock protein, but its physiological role in IVDD, especially its effect on mitochondrial fission and fusion, is still unknown. Herein, we found that compression could induce mitochondrial fission, which ultimately trigger apoptosis of NP cells via the mitochondrial apoptotic pathway. In addition, we identified the cytoprotective effects of HSP70 on NP cells, and we found that promoting the expression of HSP70 could protect NP cells from abnormal mechanical loading in vitro and in vivo. Finally, we showed that HSP70 inhibited compression-induced mitochondrial fission by promoting SIRT3 expression, thereby attenuating mitochondrial dysfunction and the production of reactive oxygen species and ultimately inhibiting the mitochondrial apoptotic pathway in NP cells. In conclusion, our results demonstrated that HSP70 could attenuate compression-induced apoptosis of NP cells by suppressing mitochondrial fission via upregulating SIRT3 expression. Promoting the expression of HSP70 might be a novel strategy for the treatment of IVDD.Subject terms: Rheumatic diseases, Apoptosis  相似文献   
920.
利用示差脉冲伏安法研究了烟酰胺(NA)与小牛胸腺DNA在pH 8.0条件下相互作用的电化学行为.双链DNA(dsDNA)或单链DNA(ssDNA)的存在导致NA的峰电流明显降低且峰电位负移,表明NA与DNA发生相互作用,生成了复合物,且其作用模式主要是静电模式,但NA与dsDNA的相互作用强于与ssDNA的相互作用,可用于识别dsDNA和ssDNA.通过dsDNA加入前后峰电流的变化,计算得出NA与dsDNA结合常数β=4.946×10(11),结合位点数m=3.此外,NA的峰电流Ip与DNA质量浓度在1~14mg/L的范围内呈线性关系,线性回归方程为Ip(10-5A)=-0.03451cDNA(mg/L)+1.7408,相关系数R为0.9998.该法具有良好的回收率和选择性,可用于样品中DNA的测定.  相似文献   
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