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1.
目的:探讨维生素D对多囊卵巢综合征(PCOS)患者胰岛素抵抗(IR)的影响及其机制研究.方法:选取自2013年2月~2014年2月在该院就诊的48例PCOS患者作为PCOS组,另选30例健康育龄期妇女作为对照组,测量研究者身高、体质量参数,计算体质指数(BMI),采用全自动生化分析仪葡萄糖氧化酶检测空腹血糖浓度(FBG)、化学发光法检测血清空腹胰岛素(FI)及胰岛素样生长因子-1(IGF-1)水平、ELISA方法测定血清25-(OH)D3浓度,计算稳态胰岛素评价指数(HOMA-IR)用于评价胰岛素抵抗性,量化胰岛素敏感指数(QUICKI)用于评价胰岛素敏感度,并分析FI、HOMA-IR、QUICKI及IGF-1与血清25-(OH)D3浓度的相关性.结果:PCOS组BMI及FBG与对照组相比,差异无统计学差异(P>0.05),而FI、HOMA-IR、QUICKI、25-(OH) D3及IGF-1与对照组比较,差异均有统计学差异(P<0.05);并且PCOS组FI和HOMA-IR与血清25-(OH)D3浓度呈显著负相关,差异有统计学意义(P<0.05),QUICKI和IGF-1水平与血清25-(OH)D3浓度呈显著正相关,差异有统计学意义(P<0.05).结论:PCOS患者IR可能与血清中维生素D缺乏有关,而IGF-1分泌减少又可能是导致PCOS患者维生素D缺乏的重要原因.  相似文献   
2.
Signaling by the transforming growth factor-β (TGF-β) superfamily is important in the regulation of hematopoiesis and is dysregulated in myelodysplastic syndromes (MDS), contributing to ineffective hematopoiesis and clinical cytopenias. TGF-β, activins and growth differentiation factors exert inhibitory effects on red cell formation by activating canonical SMAD2/3 pathway signaling. SMAD2/3 overactivation is seen in numerous subtypes of MDS. Furthermore, reduced levels of inhibitory SMAD7 are

References

  • 1.Valcarcel D, Verma A, Platzbecker U, et al. Phase 2 Study of Monotherapy Galunisertib (LY2157299 Monohydrate) in Very Low-, Low-, and Intermediate-Risk Patients with Myelodysplastic Syndromes. Blood. 2015;126:1669.
  • 2.Suragani RN, Cawley SM, Li R, Wallner S, et al. Modified activin receptor IIB ligand trap mitigates ineffective erythropoiesis and disease complications in murine β-thalassemia. Blood. 2014 Jun 19;123(25):3864-72.
  • 3.Dussiot M, Maciel TT, Fricot A, et al. Nat Med. 2014 Apr;20(4):398-407.
  • 4.
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3.
Caveolin-1 (Cav-1) appears to be both a pathophysiological contributor and a target in different inflammatory and hyperproliferative skin conditions as well as in skin aging. Skin fibroblasts demonstrate an up-regulation of Cav-1 expression both in chronological and UV-induced aging, and such an up-regulation was observed both in vitro and in vivo. Typical alterations in aging skin involve a reduction of the dermis thickness, a significant expansion of the dermal white adipose tissue as well as modifications of the content and distribution of hyaluronan, impairment of autophagic flux, a reduction of collagen expression and an increase in tissue inflammation. All of these phenomena can be connected with changes in Cav-1 expression in the aging skin. Modified expression of Cav-1 can also significantly influence the mechanical properties of individual skin layers, thus changing the total mechanical stability of the layered composite skin/WAT, leading to typical structural modifications of the skin surface in the aging skin. Selective reduction of Cav-1 expression has the potential to exert anti-aging effects on the skin.  相似文献   
4.
目的 探讨在苯妥英钠(Phenytoin,PHT)促进大鼠牙周膜干细胞(Rat periodontal ligament stem cells,rPDLSCs)、大鼠骨髓间充质干细胞(Rat Bone Marrow Mesenchymal Stem Cells,rBMMSCs)黏附于牙骨质过程中,整合素α5β1(Integrin α5β1)起到的作用。方法 提取大鼠BMMSCs和PDLSCs,培养并纯化。通过细胞鉴定后,将获得的两种细胞各分为4组:40 mg/L PHT处理组、40 mg/L PHT+整合素α5抗体处理组、40 mg/L PHT+整合素β1抗体处理组、PBS处理组,每组细胞放入置有牙骨质片的96孔板处理4 h后,检测黏附于牙骨质片上的细胞量并做以比较。最后,利用qRT-PCR和Western blot检测40 mg/L PHT组与对照组细胞的整合素α5、β1亚基的mRNA与蛋白表达量。结果 40 mg/L PHT可促进rBMMSCs及rPDLSCs黏附于牙骨质片,加入整合素α5、β1抗体后,均明显抑制了40 mg/L PHT对rBMMSCs、rPDLSCs黏附于牙骨质的促进作用(P<0.01)。qRT-PCR、Western-blot结果显示PHT处理组的整合素α5、β1亚基表达量高于空白对照组(P<0.05)。结论 40 mg/L PHT能促进rBMMSCs、rPDLSCs黏附于牙骨质,该作用与整合素α5β1的表达上调密切相关。  相似文献   
5.
《Vaccine》2019,37(31):4382-4391
Cancer-associated fibroblasts (CAFs), major components of the tumor microenvironment (TME), promote tumor growth and metastasis and inhibit the anti-tumor immune response. We previously constructed a DNA vaccine expressing human FAPα, which is highly expressed by CAFs, to target these cells in the TME, and observed limited anti-tumor effects in the 4T1 breast cancer model. When the treatment time was delayed until tumor nodes formed, the anti-tumor effect of the vaccine completely disappeared. In this study, to improve the safety and efficacy, we constructed a new FAPα-targeted vaccine containing only the extracellular domain of human FAPα with a tissue plasminogen activator signal sequence for enhanced antigen secretion and immunogenicity. The number of CAFs was more effectively reduced by CD8+ T cells induced by the new vaccine. This resulted in decreases in CCL2 and CXCL12 expression, leading to a significant decrease in the ratio of myeloid-derived suppressor cells in the TME. Moreover, when mice were treated after the establishment of tumors, the vaccine could still delay tumor growth. To facilitate the future application of the vaccine in clinical trials, we further optimized the gene codons and reduced the homology between the vaccine and the original sequence, which may be convenient for evaluating the vaccine distribution in the human body. These results indicated that the new FAPα-targeted vaccine expressing an optimized secreted human FAPα induced enhanced anti-tumor activity by reducing the number of FAPα+ CAFs and enhancing the recruitment of effector T cells in the 4T1 tumor model mice.  相似文献   
6.
This study aimed to observe the therapeutic effects of magnesium lithospermate B on acute and chronic colitis induced by dextran sodiumsulfate (DSS) and the role of inflammasome complex (NOD-like receptor protein, NLRP; apoptosis-associated speck-like protein containing, ASC; caspase-1). Establishment of acute and chronic colitis models were by using 5% DSS oral administration in BALB/C male mice. Magnesium lithospermate B (240 mg/kg body weight) was given by subcutaneous injection. Samples were collected for biomarker assay, histological examination, immunohistochemical evaluation and western blot. There was obvious increase in TNF-α level and NLPR3, ASC, and caspase-1 expressions in acute and chronic colitis groups compared with the normal control. Significant decrease of the tumor necrosis factor-α level and the expressions of NLPR3, ASC, and caspase-1 were observed after treatment with magnesium lithospermate B. This study showed that magnesium lithospermate B could be used to treat acute and chronic colitis by inhibiting the activation of the NLRP3/ASC/Caspase-1 pathway.  相似文献   
7.
8.
Introduction: The rising prevalence of musculoskeletal pathologies in developed countries has caused a dramatic impact on social welfare. Amidst these musculoskeletal pathologies is Rheumatoid arthritis (RA), a chronic systemic autoimmune disease that mostly affects the synovium. RA metabolic-associated alterations, including distorted adipokine production, enhance RA inflammatory environment. Among the altered adipokines, visfatin is particularly involved in RA inflammation and catabolism and stands out as an essential enzyme linked to critical cell features.

Areas covered: We discuss the potential mechanism supporting the contribution of visfatin to RA and the association between RA and obesity. We discuss the repurposing of cancer-tested drugs to inhibit visfatin in the context of RA. Additionally, we address the possibility of combining these drugs with current RA therapy. Finally, we explore the future of visfatin as an RA biomarker or therapeutic target.

Expert opinion: Inhibition of visfatin has become an interesting therapeutic approach for RA pathology. Such a feat has already been attained in oncology using small molecule inhibitors, which suggest that a similar course of action would be worth pursuing in the RA context. Visfatin will become an important biomarker and therapeutic target for RA.  相似文献   

9.
目的观察蛇床子素对去卵巢致骨质疏松大鼠的影响。方法选取3月龄雌性SD大鼠30只,随机分为蛇床子素组(A组)、模型对照组(B组)、假手术组(C组),各10只。A、B 2组摘除卵巢构建去势大鼠骨质疏松模型,C组仅进行手术、不摘除卵巢。造模成功后,分别给予相应药物灌胃,连续给药12周,处死。然后测量骨密度,检测治疗后血清BGP、TGF-β1、钙指标。结果B组大鼠股骨骨密度较C组明显降低(P<0.05);经12周治疗,A组股骨骨密度较B组明显升高(P<0.05)。与C组比较,B组大鼠血清中BGP含量升高、TGF-β1降低(P<0.05);与B组比较,A组大鼠血清中BGP降低、TGF-β1含量升高(P<0.05)。与C组比较,B组大鼠血清Ca水平明显降低(P<0.05);与B组比较,A组大鼠血清Ca水平明显升高(P<0.05)。差异均有统计学意义。结论蛇床子素能够有效通过调节大鼠体内激素分泌改善去卵巢大鼠的骨代谢异常,提高骨密度,对骨质疏松症起到一定的防治作用。  相似文献   
10.
《中国现代医生》2020,58(31):37-39+封三
目的 探讨脂蛋白相关磷脂酶A2(Lp-PLA2)、胰岛素样生长因子-1(IGF-1)与老年血管性痴呆(VD)患者认知功能的关系及预测价值。方法 选择2019 年3~6 月在我院接受治疗的VD 患者60 例为研究对象,同时选取同期在我院接受检查的健康者60 例为对照组,比较两组患者的Lp-PLA2、IGF-1、简易智力状态检查量表评分(MMSE)水平;采用Pearson 相关性分析法对Lp-PLA2、IGF-1 与MMSE 评分的相关性进行分析;采用受试者工作曲线(ROC)下面积(AUC)比较Lp-PLA2、IGF-1 对VD 的预测价值。结果 观察组患者的Lp-PLA2 水平明显高于对照组(P<0.05),观察组患者的IGF-1、MMSE 评分明显低于对照组(P<0.05);Lp-PLA2 与MMSE 评分呈负相关性,IGF-1 与MMSE 评分呈正相关性;Lp-PLA2 与IGF-1 诊断VD 的AUC 值分别为0.940、0.954。结论Lp-PLA2 水平越低,IGF-1 水平越高,患者的认知功能越好,且Lp-PLA2、IGF-1 对老年VD 患者均具有较高的预测价值。  相似文献   
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