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51.
52.
目的 探讨葛根芩连汤对溃疡性结肠炎(UC)小鼠肠黏膜上皮屏障功能的保护作用,并通过基质金属蛋白酶-9(MMP-9)/p38丝裂原活化蛋白激酶(p38 MAPK)信号通路探究其治疗UC的作用机制。方法 48只雌性C57BL/6小鼠随机分为正常组、模型组、柳氮磺吡啶组(0.3 g·kg-1)及葛根芩连汤高、中、低剂量组(2.84,1.42,0.71 g·kg-1)。采用3%葡聚糖硫酸钠(DSS)溶液构建UC小鼠模型,葛根芩连汤和柳氮磺吡啶于造模后第8天灌胃给药,连续7 d,正常组给予等量生理盐水处理。末次给药后取结肠组织,苏木素-伊红(HE)染色观察结肠组织病理变化,免疫组化(IHC)观察结肠组织紧密连接(TJ)蛋白,如闭合蛋白(Occludin),闭锁连接蛋白-1(ZO-1)的表达,实时荧光定量聚合酶链式反应(Real-time PCR)检测结肠组织中肿瘤坏死因子-α(TNF-α),白细胞介素-1β(IL-1β),MMP-9 mRNA表达,蛋白免疫印迹法(Western blot)检测结肠组织中磷酸化(p)-p38 MAPK,p38 MAPK和MMP-9蛋白的表达。结果 与正常组比较,模型组小鼠体质量显著下降(P<0.01),疾病活动指数(DAI)评分显著升高(P<0.01),结肠黏膜上皮破损并可见黏膜和黏膜下层炎细胞浸润明显,Occludin,ZO-1蛋白表达显著降低(P<0.01),TNF-α,IL-1β,MMP-9 mRNA相对表达量显著升高(P<0.01),p-p38 MAPK和MMP-9蛋白表达显著升高(P<0.01);与模型组比较,柳氮磺吡啶组、葛根芩连汤各剂量组小鼠体质量和DAI评分均有明显改善(P<0.05,P<0.01),结肠组织损坏明显改善,Occludin,ZO-1蛋白明显增多(P<0.05,P<0.01),TNF-α,IL-1β,MMP-9 mRNA相对表达量显著下降(P<0.01),p-p38 MAPK和MMP-9蛋白表达显著下降(P<0.01),其中葛根芩连汤各组中以中剂量组的变化最为明显。结论 葛根芩连汤能够通过抑制MMP-9和炎性细胞因子TNF-α,IL-1β的表达,阻断p38 MAPK信号通路的激活,增加TJ蛋白的表达,从而修复肠道黏膜屏障功能。 相似文献
53.
Amandine Jullienne Mary Hamer Elizabeth Haddad Alexander Morita Peter Gifford Richard Hartman William J. Pearce Jiping Tang John H. Zhang Andre Obenaus 《Journal of neuroscience research》2020,98(1):141-154
Intranasal recombinant osteopontin (OPN) has been shown to be neuroprotective in different models of acquired brain injury but has never been tested after traumatic brain injury (TBI). We used a model of moderate-to-severe controlled cortical impact in male adult Sprague Dawley rats and tested our hypothesis that OPN treatment would improve neurological outcomes, lesion and brain tissue characteristics, neuroinflammation, and vascular characteristics at 1 day post-injury. Intranasal OPN administered 1 hr after the TBI did not improve neurological score, lesion volumes, blood–brain barrier, or vascular characteristics. When assessing neuroinflammation, we did not observe any effect of OPN on the astrocyte reactivity but discovered an increased number of activated microglia within the ipsilateral hemisphere. Moreover, we found a correlation between edema and heme oxygenase-1 (HO-1) expression which was decreased in OPN-treated animals, suggesting an effect of OPN on the HO-1 response to injury. Thus, OPN may increase or accelerate the microglial response after TBI, and early response of HO-1 in modulating edema formation may limit the secondary consequences of TBI at later time points. Additional experiments and at longer time points are needed to determine if intranasal OPN could potentially be used as a treatment after TBI where it might be beneficial by activating protective signaling pathways. 相似文献
54.
Michaela Roth Andreas Enström Candice Aghabeick Robert Carlsson Guillem Genové Gesine Paul 《Journal of neuroscience research》2020,98(5):826-842
Scar formation after injury of the brain or spinal cord is a common event. While glial scar formation by astrocytes has been extensively studied, much less is known about the fibrotic scar, in particular after stroke. Platelet-derived growth factor receptor ß-expressing (PDGFRß+) pericytes have been suggested as a source of the fibrotic scar depositing fibrous extracellular matrix (ECM) proteins after detaching from the vessel wall. However, to what extent these parenchymal PDGFRß+ cells contribute to the fibrotic scar and whether targeting these cells affects fibrotic scar formation in stroke is still unclear. Here, we utilize male transgenic mice that after a permanent middle cerebral artery occlusion stroke model have a shift from a parenchymal to a perivascular location of PDGFRß+ cells due to the loss of regulator of G-protein signaling 5 in pericytes. We find that only a small fraction of parenchymal PDGFRß+ cells co-label with type I collagen and fibronectin. Consequently, a reduction in parenchymal PDGFRß+ cells by ca. 50% did not affect the overall type I collagen or fibronectin deposition after stroke. The redistribution of PDGFRß+ cells to a perivascular location, however, resulted in a reduced thickening of the vascular basement membrane and changed the temporal dynamics of glial scar maturation after stroke. We demonstrate that parenchymal PDGFRß+ cells are not the main contributor to the fibrotic ECM, and therefore targeting these cells might not impact on fibrotic scar formation after stroke. 相似文献
55.
《The surgeon》2020,18(4):202-207
IntroductionThe objective of this study is to evaluate outcomes and complications in patients with single-stage ADM-implant based immediate breast reconstruction with and without radiotherapy (RT), highlighting the effects of RT on the reconstruction.Materials and methodsThis prospective study recruited 91 consecutive patients who underwent skin-sparing, nipple-sparing or wise-pattern skin reduction mastectomy with direct-to-implant breast reconstruction with ADMs using sub-pectoral or pre-pectoral approach at the two breast units. Early and late complications like seroma, delayed wound healing, wound breakdown, infection, capsular contracture, implant loss and revision surgery were evaluated in the RT and non-RT groups.ResultsIn the total cohort of 91 patients, 29 received adjuvant RT and 62 did not need RT. In the RT group, 3–7% of them had early complications like seroma, wound infections and delayed healing. 20.7% had post-RT capsular contractures which either required revision surgery with autologous flap (6.9%) or capsulotomy with exchange of implant (6.9%). In the non-RT group, 7–9% cases had seroma & wound infections, 3.06% had delayed wound healing and 7.25% had capsular contracture. 13.04% required revision surgery due to infection, implant loss or failure to achieve expectations. The total loss of implants in the cohort was 7.14% (RT group 6.9% and non-RT group 7.25%). The need for PMRT could have been predicted pre-operatively in the RT group in 55.17% cases based on the extent of disease, multifocality, tumour grade and positive LN status on imaging.ConclusionADM based reconstruction in patients anticipated to receive adjuvant RT is always debatable. Though there is no significant difference in the revision surgeries in our study of the 2 groups, the rate of capsular contracture as expected, was higher in the RT group. Hence, pre-operative discussion on the need for RT highlighting the risks and complications will help patients make a better-informed choice. 相似文献
56.
目的探究MRI T2WI图像游程矩阵纹理分析技术联合ADC值在评估前列腺癌分化程度应用中的可行性,以期术前量化评估前列腺癌的分化程度。方法回顾性分析50例经手术病理证实的前列腺癌患者MRI影像资料,并依据Gleason评分将≤6分归为高分化组(25例);将>6分归为低分化组(25例)。对前列腺进行标准化分区,依据病理结果分别选取病变T2WI横断位图像最大层面,采用Mazda纹理分析软件勾画感兴趣区并进行游程矩阵纹理分析,并在DWI图像选取相应感兴趣区测定ADC值,对高、低分化两组前列腺癌进行数据统计分析。建立ROC曲线并计算联合预测因子进行诊断效能比较分析,对纹理参数及ADC值与分化程度之间的相关性进行检测。结果采用游程矩阵提取的5类参数中,水平方向(Horzl-GLNU)、垂直方向(Vertl-GLNU)、45度方向(45dgr-GLNU)、135度方向(135dgr-GLNU)上的灰度不均匀性(GLNU)在高、低分化两组间有显著差异(P值均<0.05)。ADC值在不同分化程度之间有显著差异(P<0.05)。Horzl-GLNU、Vertl-GLNU、45dgr-GLNU、135dgr-GLNU与分化程度呈负相关(r值分别为-0.450、-0.442、-0.470、-0.464,P值均<0.05)。ADC值与分化程度呈正相关(r值为0.423,P值<0.05)。纹理参数中,45dgr-GLNU的ROC曲线下面积(AUC)最大(0.771),敏感性和特异性分别为56.0%、92.0%。ADC值的AUC值为0.837,敏感性和特异性分别为64.0%、76.0%。联合预测因子AUC值为0.869,敏感性和特异性分别为72.0%、88.0%,诊断效能得到提升。结论基于MRI T2WI图像的游程矩阵纹理分析联合ADC值可提高对术前前列腺癌分化程度的评估效能。 相似文献
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59.
《Research in microbiology》2020,171(8):311-318
Bacterial biofilms are an important virulence factor with a vital role in evasion from the host immune system, colonization and infection. The aim of the present study was to evaluate in vitro the effects of three environmental factors (H+, glucose and human plasma) in biofilm formation, by carrier and invasive Streptococcus agalactiae strains of ST17 and ST19 sequence types, including DNase producers and non-producers. Bacteria ability to assemble biofilms was classified based on crystal violet assay. Biofilm formation was also monitored by scanning electron microscopy. Depending on the growth medium used, each bacterial isolate could fit in different biofilm production categories. Our data showed that optimal conditions for S. agalactiae biofilm assembly were reached after 48 h incubation at pH 7.6 in the presence of glucose and inactivated human plasma. In the presence of inactivated human plasma, the biofilm biomass of ST19 strains experienced a higher increase than ST17 strains. The composition of the extracellular polymeric matrix of the three strongest biofilm producers (all from ST17) was accessed by enzymatic digestion of mature biofilms and proteins were shown to be the predominant component. The detailed identification of the extracellular protein components should contribute to the development of new therapeutic strategies to fight S. agalactiae infections. 相似文献
60.
Mingxiang Cai Junhui Li Rui Yue Zuolin Wang Yao Sun 《Journal of oral rehabilitation》2020,47(Z1):19-28
Craniosynostosis, a severe craniofacial developmental disease, can only be treated with surgery currently. Recent studies have shown that proteoglycans are involved in the suture development. For the bone matrix protein, dentin matrix protein 1 (DMP1), glycosylation on the N-terminal of it could generate a functional proteoglycan form of DMP1 during osteogenesis. We identified that the proteoglycan form of DMP1 (DMP1-PG) is highly expressed in mineralisation front of suture. But, the potential role of DMP1-PG in suture fusion remain unclear. To investigate the role of DMP1-PG in cranial suture fusion and craniofacial bone development. By using a DMP1 glycosylation site mutation mouse model, DMP1-S89G mice, we compared the suture development in it with control mice. We compared the suture phenotypes, bone formation rate, expression levels of bone formation markers in vivo between DMP1-S89G mice and wild-type mice. Meanwhile, cell culture and organ culture were performed to detect the differences in cell differentiation and suture fusion in vitro. Finally, chondroitin sulphate (CHS), as functional component of DMP1-PG, was employed to test whether it could delay the premature suture fusion and the abnormal differentiation of bone mesenchymal stem cells (BMSCs) of DMP1-PG mice. DMP1-S89G mice had premature closure of suture and shorter skull size. Lack of DMP1-PG accelerated bone formation in cranial suture. DMP1-PG maintained the essential stemness of BMSCs in suture through blocking the premature differentiation of BMSCs to osteoblasts. Finally, chondroitin sulphate, a major component of DMP1-PG, successfully delayed the premature suture fusion by organ culture of skull in vitro. DMP1-PG could inhibit premature fusion of cranial suture and maintain the suture through regulating the osteogenic differentiation of BMSCs. 相似文献