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91.
Immune dysregulation is a cardinal feature of autoimmune diseases and chronic microbial infections. In particular, regulatory T cells are downregulated in autoimmune diseases while upregulated in chronic microbial infections. FOXP3 is the master regulator of Treg development. Treg-specific demethylated region (TSDR) is a highly conserved locus on the FOXP3 gene that is fully demethylated in natural Tregs but methylated in effector T cells. In our study, we used high resolution melt-polymerase chain reaction (HRM-PCR) to determine the FOXP3 TSDR methylation status in autoimmune diseases and chronic microbial infections. We found that FOXP3 TSDR to have the highest mean melting temperature (highly methylated) in active SLE patients compared to all the other groups (p?<?0.001). The psoriasis group also had a significantly high mean melting temperature (78.62?±?0.20) when compared with the inactive SLE group (78.49?±?0.29, p?<?0.05) and control group (78.44?±?0.25, p?<?0.01). There was no significant difference in melting temperature between inactive SLE and healthy controls. Disease activity in SLE was directly associated with methylation of the FOXP3 TSDR. On the other hand, patients with chronic microbial infections had significantly lower FOXP3 TSDR mean melting temperature (demethylated) when compared with healthy controls (78.28?±?0.21 vs 78.44?±?0.25, p?<?0.05). Our results suggest that the use of HRM-PCR to detect FOXP3 TSDR methylation status is a reliable and easy method to predict natural regulatory T cell levels in peripheral blood in different disease conditions. Determining FOXP3 TSDR methylation status can be a useful tool in diagnosis, and monitoring the severity of autoimmune diseases and chronic microbial infections.  相似文献   
92.
Sirt5 is known to functionally regulate mitochondrial proteins by altering posttranslational modifications, including lysine desuccinylation. While roles for Sirt5 as either a tumor promoter or suppressor, or in chemoresistance, have been implicated in other cancers, the function of Sirt5 in cutaneous melanoma has not been well examined. Therefore, to determine whether Sirt5 is necessary for BrafV600E‐mediated melanoma formation and/or disease progression, we crossed a genetically engineered murine melanoma model (TyrCreERT2/+; BrafLSLV600E/+; Ptenflox/flox) to Sirt5?/? knockout animals. In addition, we tested for synergism with a selective BRAF (V600E) inhibitor in Sirt5?/? mouse melanoma cells. Taken together, this report demonstrates that, in these models, Sirt5 is dispensable for BrafV600E‐mediated cutaneous melanoma formation and growth in vivo, and does not improve sensitivity to a selective BRAF inhibitor.  相似文献   
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Abstract

Purpose: We examined underlying psychosocial processes of a behavioral treatment for urinary incontinence (UI) of prostate cancer survivors.

Design: Secondary analysis of data collected from a clinical trial.

Sample: Two hundred forty-four prostate cancer survivors who participated in a clinical trial of behavioral intervention to UI as intervention or control subjects.

Methods: The participants had a 3-month behavioral intervention or usual care and were followed up for an additional 3?months. They were assessed at baseline, 3, and 6?months. Latent growth curve models were performed to examine trajectories of each study variable and relationships among the variables.

Findings: Increasing self-efficacy and social support were significantly and independently associated with more reduction of urinary leakage frequency over time.

Implications for psychosocial oncology: Providing problem-solving skills and social support, including peer support, are essential for empowering patients to reduce UI.  相似文献   
95.
《Journal of endodontics》2019,45(10):1228-1236
IntroductionThe balance between the host proinflammatory immune response and the counteracting anti-inflammatory and reparative responses supposedly determine the outcome of periapical lesions. In this scenario, the vasoactive intestinal peptide (VIP) may exert a protective role because of its prominent immunoregulatory capacity. In this study, we investigated (in a cause-and-effect manner) the potential involvement of VIP in the development of human and experimental periapical lesions.MethodsPeriapical granulomas (n = 124) and control samples (n = 48) were comparatively assessed for VIP and multiple immunologic/activity marker expression through real-time polymerase chain reaction. Experimental periapical lesions (C57Bl/6 wild-type mice) were evaluated regarding endogenous VIP expression correlation with lesion development and the effect of recombinant VIP therapy in lesion outcome. CCR4KO and IL4KO strains and anti-glucocorticoid-induced TNFR-related protein inhibition were used to test the involvement of Treg and Th2 cells in VIP-mediated effects.ResultsVIP expression was more prevalent in periapical granulomas than in controls, presenting a positive association with immunoregulatory factors and an inverse association/correlation with proinflammatory mediators and the receptor activator of nuclear factor kappa B ligand/osteoprotegerin ratio. Endogenous VIP expression up-regulation was temporally associated with lesion immunoregulation and a decline of bone loss. VIP therapy in mice prompted the arrest of lesion development, being associated with an anti-inflammatory and proreparative response that limits the proinflammatory, Th1, Th17, and osteoclastogenic response in the periapex. The VIP protective effect was dependent of Treg migration and activity and independent of interleukin 4.ConclusionsOur results show that VIP overexpression in human and experimental periapical lesions is associated with lesion inactivity and that VIP therapy results in the attenuation of experimental lesion progression associated with the immunosuppressive response involving Treg cells.  相似文献   
96.

Background

Chronic limb-threatening ischemia (CLTI), defined as ischemic rest pain or tissue loss secondary to arterial insufficiency, is caused by multilevel arterial disease with frequent, severe infrageniculate disease. The rise in CLTI is in part the result of increasing worldwide prevalence of diabetes, renal insufficiency, and advanced aging of the population. The aim of this study was to compare a bypass-first with an endovascular-first revascularization strategy in patients with CLTI due to infrageniculate arterial disease.

Methods

We reviewed the American College of Surgeons National Surgical Quality Improvement Program targeted lower extremity revascularization database from 2012 to 2015 to identify patients with CLTI and isolated infrageniculate arterial disease who underwent primary infrageniculate bypass or endovascular intervention. We excluded patients with a history of ipsilateral revascularization and proximal interventions. The end points were major adverse limb event (MALE), major adverse cardiovascular event (MACE), amputation at 30 days, reintervention, patency, and mortality. Multivariable logistic regression was used to determine the association of a bypass-first or an endovascular-first intervention with outcomes.

Results

There were 1355 CLTI patients undergoing first-time revascularization to the infrageniculate arteries (821 endovascular-first revascularizations and 534 bypass-first revascularizations) identified. There was no significant difference in adjusted rate of 30-day MALE in the bypass-first vs endovascular-first revascularization cohort (9% vs 11.2%; odds ratio [OR], 0.73; 95% confidence interval [CI], 0.50-1.08). However, the incidence of transtibial or proximal amputation was lower in the bypass-first cohort (4.3% vs 7.4%; OR, 0.60; CI, 0.36-0.98). Patients with bypass-first revascularization had higher wound complication rates (9.7% vs 3.7%; OR, 2.75; CI, 1.71-4.42) compared with patients in the endovascular-first cohort. Compared with the endovascular-first cohort, the incidence of 30-day MACE was significantly higher in bypass-first patients (6.9% vs 2.6%; adjusted OR, 3.88; CI, 2.18-6.88), and 30-day mortality rates were 3.23% vs 1.8% (adjusted OR, 2.77; CI, 1.26-6.11). There was no difference in 30-day untreated loss of patency, reintervention of treated arterial segment, readmissions, and reoperations between the two cohorts. In subgroup analysis after exclusion of dialysis patients, there was also no significant difference in MALE or amputation between the bypass-first and endovascular-first cohorts.

Conclusions

CLTI patients with isolated infrageniculate arterial disease treated by a bypass-first approach have a significantly lower 30-day amputation. However, this benefit was not observed when dialysis patients were excluded. The bypass-first cohort had a higher incidence of MACE compared with an endovascular-first strategy. These results reaffirm the need for randomized controlled trials, such as the Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL-2) trial and Best Endovascular vs Best Surgical Therapy in Patients with Critical Limb Ischemia (BEST-CLI), to provide level 1 evidence for the role of endovascular-first vs bypass-first revascularization strategies in the treatment of this population of challenging patients.  相似文献   
97.
目的探析经鼻高流量湿化氧疗用于小儿先心病术后治疗中的效果以及护理措施。方法2014年9月—2017年10月在郑州儿童医院外科监护室接受手术治疗的先心病患儿中随机抽取130例,根据术后氧疗方法不同分组:对照组患儿术后给予常规面罩吸氧,观察组患儿术后给予经鼻高流量湿化氧疗,2组患儿均给予优质术后护理,对比2组的血气指标、住院时间等。结果2组患者氧疗后24h、48h的血氧饱和度差异无统计学意义,在氧疗后24h的PaCO2水平差异无统计学意义,而在氧疗后24h和48h的氧合指数,观察组明显高于对照组,差异有统计学意义(P<0.05);2组ICU入住时间和总住院时间差异无统计学意义(P>0.05)。结论经鼻高流量湿化氧疗的应用提高先心病患儿术后的舒适度,改善呼吸状况,值得推广。  相似文献   
98.
目的观察1.5T场强MRI联合动物专用线圈是否可以活体示踪经门静脉移植的纳米级超顺磁性氧化铁颗粒标记的骨髓基质细胞(bone marrow stromal cells BMSCs),为介人性门静脉骨髓基质细胞移植治疗终末期肝脏疾病的研究提供进一步的依据。方法供体大鼠5只,梯度密度离心分离BMSCs,纳米级超顺磁性氧化铁颗粒和脂质体转染BMSCs,体外经普鲁士蓝染色和HE染色确定细胞标记率。受体大鼠15只,分为5组,分别为对照组和纳米级超顺磁性氧化铁颗粒标记的骨髓基质细胞经门静脉移植人正常大鼠肝脏后2h、3d、7d及2周组。1.5T场强MRI联合动物专用线圈行T1W、T2W和T2*序列扫描,观察肝脏信号改变情况,与对照组比较,并且与组织切片对照。结果纳米级超顺磁性氧化铁颗粒和脂质体转染BMSCs,细胞标记率〉95%。经门静脉移植人正常大鼠肝脏后,T2*序列扫描显示经标记的BMSCs在肝内显示弥漫性的结节性低信号影,移植后2h到2周均可见到细胞在受体肝脏内存在,组织学切片显示信号缺失部位与铁颗粒标记细胞相一致。结论纳米级超顺磁性铁氧体颗粒标记的大鼠BMSCs经门静脉移植后可以通过1、5T场强行MRI活体示踪,为临床干细胞移植的应用提供可行的示踪方法。  相似文献   
99.
100.
人间充质干细胞免疫原性研究   总被引:1,自引:0,他引:1  
目的探讨人间充质干细胞(hMSCs)特性及免疫原性,为进一步研究hMSCs移植特性提供实验依据。方法免疫组化方法鉴定hMSCs表面HLA-ABC、HLA-DR、CD80、CD86分子;流式细胞术检测其含量;RT-PCR检测HLA-ABC、HLA-DRmRNA基因片断;外周血淋巴细胞杀伤试验及 CCK-8比色法规察淋巴细胞增殖反应;将表达绿色荧光蛋白(GFP)的DNA复合物导入hMSCs进行大鼠脑内移植,观察hMSCs在脑内的存活情况。结果 hMSCs表面少量表达HLA-ABC分子,不表达 HLA-DR、CD80、CD86分子;有少量HLA-ABC mRNA基因片断存在,未发现HLA-DR mRNA基因片断;外周血淋巴细胞杀伤试验没有发现淋巴细胞增殖反应;大鼠脑内移植hMSCs一个月后仍可见有细胞存活。结论 hMSCs具有较弱的免疫原性。  相似文献   
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