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1.
《Survey of ophthalmology》2023,68(5):940-956
Congenital aniridia is a panocular disorder that is typically characterized by iris hypoplasia and aniridia-associated keratopathy (AAK). AAK results in the progressive loss of corneal transparency and thereby loss of vision. Currently, there is no approved therapy to delay or prevent its progression, and clinical management is challenging because of phenotypic variability and high risk of complications after interventions; however, new insights into the molecular pathogenesis of AAK may help improve its management. Here, we review the current understanding about the pathogenesis and management of AAK. We highlight the biological mechanisms involved in AAK development with the aim to develop future treatment options, including surgical, pharmacological, cell therapies, and gene therapies.  相似文献   
2.
目的  探讨Hsa-miR-4282在肝癌细胞系SMMC-7721中的表达及其对细胞生长的影响。方法 采用实时荧光定量PCR法检测Hsa-miR-4282在人正常肝上皮细胞系HL-7702和人肝癌细胞系MHCC97-H、SMMC-7721,以及 20例肝癌组织及其相应癌旁组织中的表达。采用瞬时转染法将Hsa-miR-4282 mimics(上调组)和Hsa-miR-4282 inhibitor(下调组)分别转染肝癌SMMC-7721细胞,上调组和下调组分别设置相应阴性对照组。转染后采用MTT法检测细胞增殖能力,平板克隆形成实验检测细胞克隆形成能力,流式细胞仪检测细胞凋亡能力。结果 Hsa-miR-4282在肝癌组织、肝癌细胞MHCC97-H及肝癌细胞SMMC-7721中的表达均低于癌旁组织及正常肝细胞HL-7702(P<0.05)。MTT实验结果显示,Hsa-miR-4282上调后肝癌SMMC-7721细胞的OD值低于其阴性对照组,而下调后OD值高于其阴性对照组 (P<0.05)。平板克隆形成实验显示,下调组的细胞克隆数高于其阴性对照组[(240±7) 个 vs (191±10) 个,P=0.005)],而上调组细胞克隆数低于基阴性对照组[(146±10) 个 vs (193±12) 个,P=0.013)]。流式细胞仪检测结果显示,Hsa-miR-4282上调组细胞凋亡率较其阴性对照组升高[(23.89±1.89)% vs(16.6±1.14)%,P=0.009)],下调组细胞凋亡率较期阴性对照组降低[(14.98±0.46)% vs (17.79±0.73)%,P=0.010]。结论 Hsa-miR-4282上调可抑制肝癌SMMC-7721细胞增殖,促进细胞凋亡,可能与肝癌的发病机制有关。  相似文献   
3.
IntroductionMany studies have been done on proteomics, genomics, epigenetic, immunogenetics in many body fluids. Among these, circulating cell-free DNA (ccfDNA) entered the literature in 1948, but it has not been studied for many years due to technological deficiencies. Following recent advances, geno-metastasis has been mentioned and new research is needed in this area. ccfDNA is known to be an important biomolecule in this regard.ObjectiveThe presence of cell-free DNA in the circulatory system may offer a tremendous opportunity to provide novel biomarkers for thyroid diseases. This experimental study was conducted to determine the amount of ccfDNA in different thyroid diseases, then to evaluate whether the ccfDNA concentration varied between the disease groups and control group.MethodsIn total, we included 121 individuals in the present study. We collected blood samples and then determined the ccfDNA concentration in plasma of collected blood samples from three groups: thyroiditis (n = 33), benign (n = 37), and malignant (n = 30) and from a control group (n = 21).ResultsThe median values of the ccfDNA groups were found as 1610, 1665, 1685 and 576 ng/mL for the thyroiditis, benign, malign, and control groups, respectively. Findings showed that the ccfDNA of the three groups was significantly higher than the control (p < 0.0001). Each group was compared in terms of ccfDNA and the p-values of benign-thyroiditis, benign-malign, and thyroiditis-malign were 0.09, 0.65, and 0.29, respectively.ConclusionsThe clear differences between thyroid diseases and controls suggest that ccfDNA is worthy of attention as a biomarker for further evaluation of different thyroid diseases. Likewise, it might indicate a clear tendency that ccfDNA can also be used to distinguish different thyroid diseases.  相似文献   
4.
目的以基因表达数据集资料为研究对象,分析BCAN基因在肾透明细胞癌中的表达情况以及对患者预后的影响。方法在Oncomine数据库中挖掘BCAN在肾透明细胞癌(ccRCC)中的表达情况。从TCGA数据库中获取ccRCC患者临床资料和目的基因的表达信息并进行统计分析。利用GEO数据库中GSE73731数据集的ccRCC样本进行基因富集分析。利用String数据库分析与BCAN相关的蛋白。结果BCAN低表达组的ccRCC患者在病理分期及T分期方面低于高表达组(P<0.001;P=0.001);N分期及M分期差异无统计学意义(P>0.05)。BCAN低表达组患者的总生存期优于高表达组(P=0.033)。BCAN基因高表达组的样本主要富集在KRAS信号通路。结论BCAN可以通过多种途径来促进肿瘤细胞的侵袭能力,有望成为ccRCC不良预后的重要生物标志物之一。  相似文献   
5.
《Vaccine》2022,40(11):1594-1605
In addition to providing pathogen-specific immunity, vaccines can also confer nonspecific effects (NSEs) on mortality and morbidity unrelated to the targeted disease. Immunisation with live vaccines, such as the BCG vaccine, has generally been associated with significantly reduced all-cause infant mortality. In contrast, some inactivated vaccines, such as the diphtheria, tetanus, whole-cell pertussis (DTPw) vaccine, have been controversially associated with increased all-cause mortality especially in female infants in high-mortality settings. The NSEs associated with BCG have been attributed, in part, to the induction of trained immunity, an epigenetic and metabolic reprograming of innate immune cells, increasing their responsiveness to subsequent microbial encounters. Whether non-live vaccines such as DTPw induce trained immunity is currently poorly understood. Here, we report that immunisation of mice with DTPw induced a unique program of trained immunity in comparison to BCG immunised mice. Altered monocyte and DC cytokine responses were evident in DTPw immunised mice even months after vaccination. Furthermore, splenic cDCs from DTPw immunised mice had altered chromatin accessibility at loci involved in immunity and metabolism, suggesting that these changes were epigenetically mediated. Interestingly, changing the order in which the BCG and DTPw vaccines were co-administered to mice altered subsequent trained immune responses. Given these differences in trained immunity, we also assessed whether administration of these vaccines altered susceptibility to sepsis in two different mouse models. Immunisation with either BCG or a DTPw-containing vaccine prior to the induction of sepsis did not significantly alter survival. Further studies are now needed to more fully investigate the potential consequences of DTPw induced trained immunity in different contexts and to assess whether other non-live vaccines also induce similar changes.  相似文献   
6.
Background: Betel quid chewing is more common among the older generation in rural areas of Malaysia. Oral cancer in Asia has been associated with the habit of chewing betel quid and areca nut. Objective:  This study aims to investigate the cytotoxic effects of betel quid and areca nut extracts on the fibroblast (L929), mouth-ordinary-epithelium 1 (MOE1) and oral squamous cell carcinoma (HSC-2) cell lines. Methods: L929, MOE1 and HSC-2 cells were treated with 0.1, 0.2 and 0.4 g/ml of betel quid and areca nut extracts for 24, 48 and 72 h. MTT assay was performed to assess the cell viability. Results: Both extracts, regardless of concentration, significantly reduced the cell viability of L929 compared with the control (P<0.05). Cell viability of MOE1 was significantly enhanced by all betel quid concentrations compared with the control (P<0.05). By contrast, 0.4 g/ml of areca nut extract significantly reduced the cell viability of MOE1 at 48 and 72 h of incubation. Cell viability of HSC-2 was significantly lowered by all areca nut extracts, but 0.4 g/ml of betel quid significantly increased the cell viability of HSC-2 (P<0.05). Conclusion: Areca nut extract is cytotoxic to L929 and HSC-2, whereas the lower concentrations of areca nut extract significantly increased the cell viability of MOE1 compared to the higher concentration and control group. Although betel quid extract is cytotoxic to L929, the same effect is not observed in MOE1 and HSC-2 cell lines. Further investigations are needed to clarify the mechanism of action.  相似文献   
7.

Background

Since recent reports have shown that (-)-Epigallocatechin-3-gallate (EGCG) could be used for treating proliferative and inflammatory disorders, we explored its use for the management of corneal chemical burns.

Materials and methods

Initially, EGCG was assayed on the rabbit corneal epithelial cell line RCE1(5T5) to establish the best testing conditions, and to avoid unwanted outcomes in the experimental animals. Then, we studied its effects on cell proliferation, cell cycle progression and cell differentiation. Afterwards, we instilled EGCG in experimental grade II corneal alkali burns in mice, three times a day up to 21 days, and evaluated by slit lamp examination and histological sections of corneal epithelial, corneal endothelial and stromal edema, as well as the presence of inflammatory cells and neovascularization.

Results

EGCG reduced cell growth and led to a decline in the proportion of proliferative cells in a concentration dependent manner. At 10 μM, EGCG promoted cell differentiation, an effect not related with apoptosis or cytotoxicity. When 10 μM EGCG was instilled in corneal alkali burns in mice three times a day up to 21 days, EGCG significantly reduced corneal opacity and neovascularization. The improved clinical appearance of the cornea was associated to a controlled epithelial growth; epithelial morphology was similar to that observed in normal epithelium and contrasted with the hyperproliferative, desquamating epithelium observed in control burn wounds. EGCG reduced corneal, stromal and endothelial edema, and wound inflammation.

Conclusion

This work constitutes the first evidence for the use of EGCG in the acute phase of a corneal alkali burn, representing a possible novel alternative to improve patient outcomes as an add-on therapy.  相似文献   
8.
9.
The chemical composition, structure and surface characteristics of biomaterials/scaffold can affect the adsorption of proteins, and this in turn influences the subsequent cellular response and tissue regeneration. With magnesium/calcium phosphate cements (MCPC) as model, the effects of magnesium (Mg) on the initial adhesion and osteogenic differentiation of bone marrow stromal cells (BMSCs) as well as the underlying mechanism were investigated. A series of MCPCs with different magnesium phosphate cement (MPC) content (0∼20%) in calcium phosphate cement (CPC) were synthesized. MCPCs with moderate proportion of MPC (5% and 10%, referred to as 5MCPC and 10MCPC) were found to effectively modulate the orientation of the adsorbed fibronectin (Fn) to exhibit enhanced receptor binding affinity, and to up-regulate integrin α5β1 expression of BMSCs, especially for 5MCPC. As a result, the attachment, morphology, focal adhesion formation, actin filaments assembly and osteogenic differentiation of BMSCs on 5MCPC were strongly enhanced. Further in vivo experiments confirmed that 5MCPC induced promoted osteogenesis in comparison to ot her CPC/MCPCs. Our results also suggested that the Mg on the underlying substrates but not the dissolved Mg ions was the main contributor to the above positive effects. Based on these results, it can be inferred that the specific interaction of Fn and integrin α5β1 had predominant effect on the MCPC-induced enhanced cellular response of BMSCs. These results provide a new strategy to regulate BMSCs adhesion and osteogenic differentiation by adjusting the Mg/Ca content and distribution in CPC, guiding the development of osteoinductive scaffolds for bone tissue regeneration.  相似文献   
10.
Malignant glioma is the most common intracranial tumor with a dismal prognosis. The radiosensitizing effect of silver nanoparticles (AgNPs) on glioma both in vitro and in vivo had been demonstrated in the previous studies of our group. However, the underlying mechanism is still unclear. Consistent with previous studies, a size and dose dependent antitumor effect and significant radiosensitivity enhancing effect of AgNPs were observed in our experiment system. We also found that cell protective autophagy could be induced by AgNPs and/or radiation, which was verified by the use of 3-MA. The mechanism through which had autophagy and the enhancement of radiosensitivity taken place was further investigated with inhibitors of ERK and JNK pathways. We demonstrated that ERK and JNK played pivotal roles in the radiosensitivity enhancement. Inhibiting ERK and JNK with U0126 and SP600125 respectively, we found that the autophagy level of the cells treated with AgNPs and radiation were attenuated. Moreover, SP600125 down-regulated the apoptosis rate of the co-treated cells significantly. Taken together, the present study would have important impact on biomedical applications of AgNPs and clinical treatment for glioma.  相似文献   
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