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11.
This report describes the development of polyplexes based on CXCR4-inhibiting poly(ethylenimine) derivative (PEI-C) for pulmonary delivery of siRNA to silence plasminogen activator inhibitor-1 (siPAI-1) as a new combination treatment of pulmonary fibrosis (PF). Safety and delivery efficacy of the PEI-C/siPAI-1 polyplexes was investigated in vitro in primary lung fibroblasts isolated from mice with bleomycin-induced PF. Biodistribution analysis following intratracheal administration of fluorescently labeled polyplexes showed prolonged retention in the lungs. Treatment of mice with bleomycin-induced PF using the PEI-C/siPAI-1 polyplexes resulted in a significant down-regulation of the PAI-1 expression and decreased collagen deposition in the lung. The results of this study provide first evidence of the potential benefits of combined inhibition of CXCR4 and PAI-1 in the pulmonary treatment of PF.  相似文献   
12.
Parkinson’s disease (PD) is second most common neurodegenerative disorder worldwide. Although drugs and surgery can relieve the symptoms of PD, these therapies are incapable of fundamentally treating the disease. For PD patients, over-expression of α-synuclein (SNCA) leads to the death of dopaminergic neurons. This process can be prevented by suppressing SNCA over-expression through RNA interference. Here, we successfully synthesized gold nanoparticles (GNP) composites (CTS@GNP-pDNA-NGF) via the combination of electrostatic adsorption and photochemical immobilization, which could load plasmid DNA (pDNA) and target specific cell types. GNP was transfected into cells via endocytosis to inhibiting the apoptosis of PC12 cells and dopaminergic neurons. Simultaneously, GNP composites are also used in PD models in vivo, and it can successfully cross the blood-brain barrier by contents of GNP in the mice brain. In general, all the works demonstrated that GNP composites have good therapeutic effects for PD models in vitro and in vivo.  相似文献   
13.
According to the National Center of Health Statistics, cancer was the culprit of nearly 600,000 deaths in 2016 in the USA. It is by far one of the most heterogeneous diseases to treat. Treatment for metastasized cancers remains a challenge despite modern diagnostics and treatment regimens. For this reason, alternative approaches are needed. Chemoprevention using dietary phytochemicals such as triterpenoids, isothiocyanates, and curcumin in the prevention of initiation and/or progression of cancer poses a promising alternative strategy. However, significant challenges exist in the extrapolation of in vitro cell culture data to in vivo efficacy in animal models and to humans. In this review, the dose at which these phytochemicals elicit a response in vitro and in vivo of a multitude of cellular signaling pathways will be reviewed highlighting Nrf2-mediated antioxidative stress, anti-inflammation, epigenetics, cytoprotection, differentiation, and growth inhibition. The in vitro-in vivo dose response of phytochemicals can vary due, in part, to the cell line/animal model used, the assay system of the biomarker used for the readout, chemical structure of the functional analog of the phytochemical, and the source of compounds used for the treatment study. While the dose response varies across different experimental designs, the chemopreventive efficacy appears to remain and demonstrate the therapeutic potential of triterpenoids, isothiocyanates, and curcumin in cancer prevention and in health in general.  相似文献   
14.
Human infertility is a healthcare problem that has a worldwide impact. Genetic causes of human infertility include chromosomal aneuploidies and rearrangements and single-gene defects. The sex chromosomes (X and Y) are critical players in human fertility since they contain several genes essential for sex determination and reproductive traits for both men and women. This paper provides a review of the most common sex chromosomes-linked single-gene disorders involved in human infertility and their corresponding phenotypes. In addition to the Y-linked SRY gene, which mutations may cause XY gonadal dysgenesis and sex reversal, the deletions of genes present in AZF regions of the Y chromosome (DAZ, RBMY, DBY and USP9Y genes) are implicated in varying degrees of spermatogenic dysfunction. Furthermore, a list of X-linked genes (KAL1, NR0B1, AR, TEX11, FMR1, PGRMC1, BMP15 and POF1 and 2 regions genes (XPNPEP2, POF1B, DACH2, CHM and DIAPH2)) were reported to have critical roles in pubertal and reproductive deficiencies in humans, affecting only men, only women or both sexes. Mutations in these genes may be transmitted to the offspring by a dominant or a recessive inheritance.  相似文献   
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目的探讨浅表食管癌侵袭深度及分化程度与区域淋巴结转移的关系。方法本院2002年6月至2004年6月总共手术治疗食管癌923例,其中早期浅表食管癌68例,本文就对其术后侵袭深度及分化程度与区域淋巴结转移情况进行回顾性分析。结果本组无手术死亡,全组淋巴结转移率27%,其中高出黏膜型食管癌的淋巴结转移率为38%,侵袭越深,淋巴结转移率越高;分化程度越低淋巴结转移率越高。结论高度重视浅表型食管癌的根治性,对早期食管癌也应按肿瘤外科的原则行食管的次全切除术并常规清扫区域淋巴结。  相似文献   
17.
Comprehensive data on hepatitis C virus (HCV) genotypes distribution is critical for treatment regimen selection, vaccine design, and drug development. This study aimed to understand the dynamic distribution of HCV genotypes in Mainland China. Three hundred sixty-two studies published from January 1993 to December 2017 involving 64 891 samples (5133 injecting drug users, 2748 volunteer blood donors, 1509 former paid plasma donors, 160 sexually encounters, and 1992 human immunodeficiency virus (HIV)/HCV coinfection patients) were eligible for the quantitative synthesis estimation. Pooled proportion of HCV genotypes (and 95% confidence intervals [CIs]) was estimated through the Freeman-Tukey double arcsine transformation by period, region, and risk group. A sharp decline of the subtype 1b was observed in all regions except in northwestern and central regions. The genotypes 3 and 6 showed an obvious increase in southern and southwestern regions and have already spread nationwide. After 2010, subtype 1b was the most dominant variant in all regions and risk groups, accounting for 54.0% (95% CI, 51.9-56.1) of all national infections. Subtype 2a was the second most prevalent strain in all regions except in the south and southwest, with 15.4% (95% CI, 13.1-17.8) national infections. The subtype 6a in southern region and 3b and 3a in southwestern region had a higher proportion of infections than that in other regions. In addition, the genotypes 3 and 6 are already prevalent in almost all risk groups. The distribution of HCV genotypes were sharply shifting in China in the past three decades. The HCV subtype 1b posed a sharp decline, whereas genotypes 3 and 6 played an increasing role in the regional and populational HCV pandemic.  相似文献   
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Yin  Nannan  Yang  Yaping  Wang  Xiaoyan  Yang  Chao  Ma  Xiaofei  Shaukat  Aftab  Zhao  Gan  Deng  Ganzhen 《Inflammation research》2019,68(3):231-240
Objective

In both humans and animals, endometritis is severe inflammation of the uterus, and it causes great economic losses in dairy cow production. MicroRNAs have been reported to play an important role in various inflammatory diseases. However, the regulatory mechanisms of miR-19a in endometritis remain unclear. Thus, the aims of this study are to investigate the role of miR-19a in a mouse model of lipopolysaccharide (LPS)-induced endometritis and elucidate the possible mechanisms in bovine endometrial epithelial cells (bEECs).

Methods and results

Histological analysis showed that LPS induced severe pathological changes, suggesting that the endometritis mouse model was well established. The qPCR assay indicated that miR-19a expression in the uterine tissues of mice with endometritis and in bEECs with LPS stimulation was significantly reduced. The overexpression of miR-19a significantly decreased the expression of inflammatory cytokines (TNF-α, IL-6 and IL-1β) and the phosphorylation of NF-κB p65 and IκBα. Similar results were also obtained following the knockdown of TBK1. Furthermore, a dual luciferase reporter assay further validated that miR-19a inhibited TBK1 expression by binding directly to the 3′-UTR of TBK1.

Conclusion

We demonstrated that miR-19a has anti-inflammatory effects and mediates the negative regulation of the NF-κB Pathway in LPS-induced endometritis by targeting TBK1.

  相似文献   
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