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Background

Vitiligo is an autoimmune disease with varying pathological features. Activation of the CCL20-CCR6 axis plays an important role in chronic inflammatory diseases. However, whether CCL20-CCR6 and Th1/17 cells are indicative of active vitiligo is unclear.

Objective

To investigate the potential role of CCL20 and the involvement of Th1/17 and Tc1/17 cells in the mechanism in vitiligo.

Methods

One hundred patients with vitiligo, and 20 healthy controls were included. The serum and blister fluid IL-17, IFN-γ, CCL20, and CXCL10 were studied using enzyme-linked immunosorbent assays. The numbers of Th1/17 cells and Tc1/17 cells in circulation were quantified using flow cytometry. CCR6 mRNA in peripheral blood mononuclear cells (PBMCs) was analyzed by real-time polymerase chain reaction and the protein level was confirmed by western blotting. CCR6 and CCL20 expression in lesions was analyzed by immunohistochemistry.

Results

The serum CCL20 level was significantly elevated in patients with vitiligo. The level of serum CCL20 was higher in active than in the stable stage, which correlated positively with the Vitiligo European Task Force spreading score and the Vitiligo Area Scoring Index score. Patients with active vitiligo had elevated numbers of circulating Th1/17 cells and Tc1/17 cells, and upregulated expression of CCR6 in PBMCs and lesions. After effective treatment, the level of CCL20 in sera and blister fluid was significantly decreased, as were the numbers of circulating Th1/17 cells and Tc1/17 cells.

Conclusion

CCL20 might be a vital biomarker of active vitiligo, and circulating Th1/17 and Tc1/17 cells are involved in the pathogenesis of vitiligo.  相似文献   
13.
Objective: The main pathological change of Parkinson’s disease (PD) is progressive degeneration and necrosis of dopaminergic neurons in the midbrain, forming a Lewy body in many of the remaining neurons. Studies have found that in transgenic Drosophila, mutations in the PTEN-inducible kinase 1 (PINK1) gene may cause indirect flight muscle defects in Drosophila, and mitochondrial structural dysfunction as well.

Methods: In this study, Wnt4 gene overexpression and knockdown were performed in PINK1 mutant PD transgenic Drosophila, and the protective effect of Wnt4 gene on PD transgenic Drosophila and its possible mechanism were explored. The Wnt4 gene was screened in the previous experiment; And by using the PD transgenic Drosophila model of the MHC-Gal4/UAS system, the PINK1 gene could be specifically activated in the Drosophila muscle tissue.

Results: In PINK1 mutation transgenic fruit flies, the Wnt4 gene to study its implication on PD transgenic fruit flies’ wing normality and flight ability. We found that overexpression of Wnt4 gene significantly reduced abnormality rate of PD transgenic Drosophila and improved its flight ability, and then, increased ATP concentration, enhanced mitochondrial membrane potential and normalized mitochondrial morphology were found. All of these findings suggested Wnt4 gene may have a protective effect on PD transgenic fruit flies. Furthermore, in Wnt4 gene overexpression PD transgenic Drosophila, down-regulation autophagy and apoptosis-related proteins Ref(2)P, Pro-Caspase3, and up-regulation of Beclin1, Atg8a, Bcl2 protein were confirmed by Western Blotting.

Conclusion: The results imply that the restoring of mitochondrial function though Wnt4 gene overexpression in the PINK1 mutant transgenic Drosophila may be related to autophagy and/or apoptosis.  相似文献   

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BACKGROUND AND PURPOSE:The coronavirus disease 2019 (COVID-19) pandemic has led to decreases in neuroimaging volume. Our aim was to quantify the change in acute or subacute ischemic strokes detected on CT or MR imaging during the pandemic using natural language processing of radiology reports.MATERIALS AND METHODS:We retrospectively analyzed 32,555 radiology reports from brain CTs and MRIs from a comprehensive stroke center, performed from March 1 to April 30 each year from 2017 to 2020, involving 20,414 unique patients. To detect acute or subacute ischemic stroke in free-text reports, we trained a random forest natural language processing classifier using 1987 randomly sampled radiology reports with manual annotation. Natural language processing classifier generalizability was evaluated using 1974 imaging reports from an external dataset.RESULTS:The natural language processing classifier achieved a 5-fold cross-validation classification accuracy of 0.97 and an F1 score of 0.74, with a slight underestimation (−5%) of actual numbers of acute or subacute ischemic strokes in cross-validation. Importantly, cross-validation performance stratified by year was similar. Applying the classifier to the complete study cohort, we found an estimated 24% decrease in patients with acute or subacute ischemic strokes reported on CT or MR imaging from March to April 2020 compared with the average from those months in 2017–2019. Among patients with stroke-related order indications, the estimated proportion who underwent neuroimaging with acute or subacute ischemic stroke detection significantly increased from 16% during 2017–2019 to 21% in 2020 (P = .01). The natural language processing classifier performed worse on external data.CONCLUSIONS:Acute or subacute ischemic stroke cases detected by neuroimaging decreased during the COVID-19 pandemic, though a higher proportion of studies ordered for stroke were positive for acute or subacute ischemic strokes. Natural language processing approaches can help automatically track acute or subacute ischemic stroke numbers for epidemiologic studies, though local classifier training is important due to radiologist reporting style differences.

There is much concern regarding the impact of the coronavirus disease 2019 (COVID-19) pandemic on the quality of stroke care, including issues with hospital capacity, clinical resource re-allocation, and the safety of patients and clinicians.1,2 Previous reports have shown that there have been substantial decreases in stroke neuroimaging volume during the pandemic.3,4 In addition, acute ischemic infarcts have been found on neuroimaging studies in many hospitalized patients with COVID-19, though the causal relationship is unclear.5,6 Studies like these and other epidemiologic analyses usually rely on the creation of manually curated databases, in which identification of cases can be time-consuming and difficult to update in real-time. One way to facilitate such research is to use natural language processing (NLP), which has shown utility for automated analysis of radiology report data.7 NLP algorithms have been developed previously for the classification of neuroradiology reports for the presence of ischemic stroke findings and acute ischemic stroke subtypes.8,9 Thus, NLP has the potential to facilitate COVID-19 research.In this study, we developed an NLP machine learning model that classifies radiology reports for the presence or absence of acute or subacute ischemic stroke (ASIS), as opposed to chronic stroke. We used this model to quantify the change in ASIS detected on all CT or MR imaging studies performed at a large comprehensive stroke center during the COVID-19 pandemic in the United States. We also evaluated NLP model generalizability and different training strategies using a sample of radiology reports from a second stroke center.  相似文献   
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Objective To investigate the predictive value of nutritional and fluid status measured by bioelectrical impedance methods for the prognosis of acute kidney injury (AKI) patients undergoing continuous renal replacement therapy (CRRT). Methods Patients with severe AKI received CRRT in the First Affiliated Hospital of Nanjing Medical University from September 2016 to September 2018 were enrolled, and divided into death group and survival group according to 28-day survival. Cox regression was used to analyze the association between 28-day survival and lean tissue index (LTI), fat tissue index (FTI), the ratio of extracellular water (ECW) and body cell mass (BCM) (ECW/BCM), and overhydration (OH), respectively. Results A total of 156 patients were included, including 101 males and 55 females. The age was (62.7±15.4) years, with sequential organ failure assessment (SOFA) score of 9.9±3.9. The 28-day mortality rate was 46.2%. The pre-CRRT OH values in the 28-day survival group and death group were 2.95(1.80, 5.50) L and 4.20(2.95, 5.70) L(P=0.016), and ECW/BCM values were 1.00(0.76, 1.18) and 1.07(0.88, 1.25) (P=0.033), respectively. Univariate Cox regression analysis showed that pre-CRRT high OH values (HR=1.08, 95%CI 1.00-1.17, P=0.040) and high ECW/BCM values (HR=3.02, 95%CI 1.46-6.22, P=0.003) were associated with 28-day death. The changes of OH values (HR=0.83, 95%CI 0.72-0.95, P=0.008) and ECW/BCM values (HR=6.79, 95%CI 1.72-26.82, P=0.006) between pre-CRRT and the 7th day after CRRT initiation were significantly associated with 28-day mortality in patients who survived 7 days after CRRT initiation. After adjusting for age, gender, and SOFA scores, multivariate Cox regression analysis showed that the high OH value (HR=1.16, 95%CI 1.06-1.27, P=0.002) and the high ECW/BCM value (HR=2.80, 95%CI 1.30-6.06, P=0.003) before CRRT, the change of OH value (HR=0.82, 95%CI 0.72-0.95, P=0.008) and ECW/BCM value (HR=2.79, 95%CI 1.30-5.98, P=0.009) between the 7th day after CRRT initiation and pre-CRRT, were independently associated with 28-day death, while LTI (HR=0.93, 95%CI 0.86-1.02, P=0.113) and FTI (HR=0.98, 95%CI 0.92-1.04, P=0.475) before CRRT were uncorrelated with 28-day death. Conclusions In bioelectrical impedance analysis, the high OH value and high ECW/BCM value before CRRT are associated with 28-day mortality in patients with AKI, while the nutritional indicators LTI and FTI before CRRT are not significantly related. The correction of fluid overload by CRRT within 7 days may reduce the risk of 28-day mortality.  相似文献   
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In the previous research, we found that anticancer agent LS-1-2F could cause the vacuolation of tumor cells. Herein we investigated the effect of compound LS-1-2F on the endocytosis of macromolecules, including fluorescence quantum dots, human serum albumin, single-stranded RNA, and monoclonal antibody, into tumor cells. We found that LS-1-2F could accelerate the endocytosis of these large molecules by laser confocal microscope and flow cytometry. The effect of LS-1-2F on the improvement of the internalization efficiency of Herceptin biosimilar was particularly significant. Promoting endocytosis will help increase the efficiency of liquid-phase drug uptake in drug-resistant cancer cells and could potentially facilitate the use of drugs in nanoparticle delivery vehicles.  相似文献   
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目的:葛根总黄酮(PTF)可治疗心脑血管疾病,但膜通透性差,口服生物利用度低。一些辅料如卡波姆、壳聚糖和羟丙基甲基纤维素可以提高口服生物利用度。传统的体外评价技术,包括大鼠肠灌流和细胞模型,不能评价PTF整体的吸收机制。方法:本研究评价辅料的黏附性及对PTF在Caco-2细胞单层模型中转运的影响。采用cDNA微阵列测定PTF和PTF+辅料给药后的Caco-2细胞的基因表达变化,从基因水平揭示辅料对PTF整体吸收的影响机制。结果:体外黏附和Caco-2细胞转运实验表明,与单独PTF相比,加入辅料后对胃黏膜具有更高的黏附性,且在Caco-2细胞模型中的转运效率更高。PTF与辅料的相互作用显著改变了某些基因的表达,可能影响PTF的吸收效率。结论:不同的生物黏附聚合物能提高PTF的肠道吸收,可能与ATP结合盒(ABC)和溶质载体转运体(SLC)的表达基因有关。  相似文献   
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