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101.
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   
102.
陈科第 《传染病信息》2022,35(2):135-140
[摘要] 目的 探究HBV相关慢加急性肝衰竭(HBV-related acute-on-chronic liver failure, HBV-ACLF)患者血清中微小核糖核酸(microRNA, miR)-122和高迁移率族蛋白1(high-mobility group box-B1, HMGB1)水平及其与病情、预后的关系。方法 回顾性分析2016年1月—2018年1月我院收治的120例HBV-ACLF患者的一般及临床资料。根据临床结局,将患者分为存活组(53例)和死亡组(67例)。比较2组患者的一般资料、实验室检查指标及血清miR-122、HMGB1水平。多因素Logistic回归分析影响患者预后的因素。Pearson检验分析miR-122、HMGB1水平分别与TBIL、PA、终末期肝病评分模型(the model of end-stage liver disease score, MELD)评分的相关性。ROC曲线分析miR-122和HMGB1水平对患者的死亡预测价值,获得最佳临界值。根据临界值将患者分为A组、B组和C组,用Kaplan-Meier法绘制生存曲线,比较3组患者在3年随访期间的生存率。结果 存活组和死亡组患者的年龄、身体质量指数、并发症、病情分期、MELD评分、ALB、球蛋白、TBIL、ALT、AST、LDH、PT、PTA、HBV DNA、miR-122、HMGB1相比,差异均具有统计学意义(P均<0.05)。年龄、并发症、病情分期、MELD评分、TBIL、PT、PTA、miR-122、HMGB1均是影响患者预后的危险因素(P均<0.05)。miR-122、HMGB1水平分别与TBIL、MELD评分呈显著正相关,与PTA呈显著负相关(P均<0.05)。miR-122和HMGB1预测患者死亡的最佳临界值分别为31.42和14.56 μg/L。A组患者预后3年内生存率显著高于B组和C组(P均<0.05)。结论 miR-122和HMGB1水平与HBV-ACLF患者的病情和死亡预后密切相关,可间接反映患者的病情严重程度,在HBV-ACLF的诊断及预后中具有重要价值。  相似文献   
103.

Background

Rosacea is a chronic inflammatory skin condition whose etiology has been linked to mast cells and the antimicrobial peptide cathelicidin LL-37. Individuals with refractory disease have demonstrated clinical benefit with periodic injections of onabotulinum toxin, but the mechanism of action is unknown.

Objectives

To investigate the molecular mechanism by which botulinum toxin improves rosacea lesions.

Methods

Primary human and murine mast cells were pretreated with onabotulinum toxin A or B or control. Mast cell degranulation was evaluated by β-hexosaminidase activity. Expression of botulinum toxin receptor Sv2 was measured by qPCR. The presence of SNAP-25 and VAMP2 was established by immunofluorescence. In vivo rosacea model was established by intradermally injecting LL-37 with or without onabotulinum toxin A pretreatment. Mast cell degranulation was assessed in vivo by histologic counts. Rosacea biomarkers were analyzed by qPCR of mouse skin sections.

Results

Onabotulinum toxin A and B inhibited compound 48/80-induced degranulation of both human and murine mast cells. Expression of Sv2 was established in mouse mast cells. Onabotulinum toxin A and B increased cleaved SNAP-25 and decreased VAMP2 staining in mast cells respectively. In mice, injection of onabotulinum toxin A significantly reduced LL-37-induced skin erythema, mast cell degranulation, and mRNA expression of rosacea biomarkers.

Conclusions

These findings suggest that onabotulinum toxin reduces rosacea-associated skin inflammation by directly inhibiting mast cell degranulation. Periodic applications of onabotulinum toxin may be an effective therapy for refractory rosacea and deserves further study.  相似文献   
104.
105.
《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   
106.
Our aim was to evaluate the long-term skeletal stability of the mandible in 21 patients after orthognathic surgery with physiological positioning. The measurement points SNB, B point (X, Y), Pog (X, Y), and the angle of the ramus were measured on cephalometric photographs to assess skeletal stability preoperatively, immediately after operation, and one and two years postoperatively. In addition, we evaluated the clinical symptoms of disorders of the temporomandibular joint (TMJ). The analysis of the cephalometric photographs showed that SNB, B point X, and Pog X showed no significant differences among the postoperative time points. On the other hand, B point Y and Pog Y showed no significant differences throughout the study period. We compared the angle of the ramus before operation and two years postoperatively, and no significant difference was found. In addition, no cases showed any pathological symptoms of disorders of the TMJ two years postoperatively. The long-term stability after orthognathic surgery with physiological positioning was confirmed, and it seems to be a reliable orthognathic treatment in patients with mandibular prognathism.  相似文献   
107.
108.
109.
《Vaccine》2019,37(24):3234-3240
Leucine aminopeptidase (FhLAP) and cathepsin L1 (FhCL1) of Fasciola hepatica play a critical role in parasite feeding, migration through host tissue, and immune evasion. These antigens have been tested for immune protection as single components with variable degrees of success. The chimeric-protein approach could improve protection levels against fasciolosis. Previously, we reported the design and construction of a chimeric protein composed of antigenic sequences of FhLAP and FhCL1 of F. hepatica. The goal of the present study was to express and evaluate the immune-protective capacity of this chimeric protein (rFhLAP-CL1) in sheep. Animals were randomly allocated into five groups with five animals in each group. Groups 1, 2 and 3 were immunized twice with 100 μg, 200 μg and 400 μg of rFhLAP-CL1 emulsified with Quil A adjuvant, whereas groups 4 and 5 were the adjuvant control and infection control groups, respectively. The animals were then challenged with 200 metacercariae two weeks after the rFhLAP-CL1 booster. The fluke burden was reduced by 25.5%, 30.7% (p < 0.05) and 46.5% (p < 0.01) in sheep immunized with 100 μg, 200 μg and 400 μg of chimeric protein, respectively, in comparison to the infection control group. There was a reduction of 22.7% (p < 0.05) and 24.4% (p < 0.01) in fecal egg count in groups 2 and 3, respectively, compared to the infection control group. Sheep immunized with chimeric protein produced F. hepatica excretion-secretion product-specific total IgG antibody, which were increased after challenge. Moreover, the levels of rFhLAP-CL1-specific IgG1 and IgG2 isotypes in immunized sheep increased rapidly two weeks after the first immunization and were significantly more elevated than those of the control groups, indicating a mixed Th1/Th2 response. This is a preliminary evaluation of the chimeric protein rFhLAP-CL1 as a possible immunogen against F. hepatica infection in sheep.  相似文献   
110.
Syphilis is a sexually transmitted disease caused by Treponema pallidum. Syphilitic aortitis might coexist in a dysfunctional aortic valve, but the etiology remains unclear, because microbiological diagnosis is difficult. A 62-year-old man with low-grade fever was diagnosed with aortitis and infective endocarditis, due to Treponema pallidum infection, using polymerase chain reaction analysis. This case suggests that syphilis might cause infective endocarditis.  相似文献   
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