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1.
Both microRNAs (miRNAs) and purinergic signalling are widely and respectively expressed in various tissues of different organisms and play vital roles in a variety of physiological and pathological processes. Here, we reviewed the current publications contributed to the relationship of miRNAs and purinergic signalling in cardiovascular diseases, gastrointestinal diseases, neurological diseases, and ophthalmic diseases. We tried to decode the miRNAs-purinergic signalling network of purinergic signalling involved diseases. The evidence indicated that more than 30 miRNAs (miR-22, miR-30, miR-146, miR-150, miR-155, miR-187, etc.) directly or indirectly modulate P1 receptors (A1, A2A, A2B, A3), P2 receptors (P2X1, P2X3, P2X4, P2X7, P2Y2, P2Y6, P2Y12), and ecto-enzymes (CD39, CD73, ADA2); P2X7 and CD73 could be modulated by multiple miRNAs (P2X7: miR-21, miR-22, miR-30, miR-135a, miR-150, miR-186, miR-187, miR-216b; CD73: miR-141, miR-101, miR-193b, miR-340, miR-187, miR-30, miR-422a); miR-187 would be the common miRNA to modulate P2X7 and CD73.  相似文献   
2.
Cranial placodes are ectodermal regions that contribute extensively to the vertebrate peripheral sensory nervous system. The development of the ophthalmic trigeminal (opV) placode, which gives rise only to sensory neurons of the ophthalmic lobe of the trigeminal ganglion, is a useful model of sensory neuron development. While key differentiation processes have been characterized at the tissue and cellular levels, the signaling pathways governing opV placode development have not. Here we tested in chick whether the canonical Wnt signaling pathway regulates opV placode development. By introducing a Wnt reporter into embryonic chick head ectoderm, we show that the canonical pathway is active in Pax3+ opV placode cells as, or shortly after, they are induced to express Pax3. Blocking the canonical Wnt pathway resulted in the failure of targeted cells to adopt or maintain an opV fate, as assayed by the expression of various markers including Pax3, FGFR4, Eya2, and the neuronal differentiation markers Islet1, neurofilament, and NeuN, although, surprisingly, it led to upregulation of Neurogenin2, both in the opV placode and elsewhere in the ectoderm. Activating the canonical Wnt signaling pathway, however, was not sufficient to induce Pax3, the earliest specific marker of the opV placode. We conclude that canonical Wnt signaling is necessary for normal opV placode development, and propose that other molecular cues are required in addition to Wnt signaling to promote cells toward an opV placode fate.  相似文献   
3.
The chick ciliary ganglion is a neural crest-derived parasympathetic ganglion that innervates the eye. Here, we examine its axial level of origin and developmental relationship to other ganglia and nerves of the head. Using small, focal injections of DiI, we show that neural crest cells arising from both the caudal half of the midbrain and the rostral hindbrain contribute to the ciliary as well as the trigeminal ganglion. Precursors to both ganglia have overlapping migration patterns, moving first ventrolaterally and then rostrally toward the optic vesicle. At the level of the midbrain/forebrain junction, precursors to the ciliary ganglion separate from the main migratory stream, turn ventromedially, and condense in the vicinity of the rostral aorta and Rathke's pouch. Ciliary neuroblasts first exit the cell cycle at early E2, prior to and during ganglionic condensation, and neurogenesis continues through E5.5. By E3, markers of neuronal differentiation begin to appear in this population. By labeling the ectoderm with DiI, we discovered a new placode, caudal to the eye and possibly contiguous to the trigeminal placode, that contributes a few early differentiating neurons to the ciliary ganglion, oculomotor nerve, and connecting branches to the ophthalmic nerve. These results suggest for the first time a dual neural crest and placodal contribution to the ciliary ganglion and associated nerves.  相似文献   
4.
目的:了解眼科手术等候期患者家属对健康教育的需求。方法:采用自行设计的调查问卷对100名在患者手术过程中等候的家属进行调查。调查内容包括手术等候中希望获得的相关信息及其需求程度,需要的健康教育方式及每种健康教育的需求程度。结果:1).眼科手术等候中,家属强烈需要的信息有手术效果(76%)、术后饮食指导(60.4%)、手术费用(57.3%)、患者目前病情(54.2%)、术后头位指导(51%)。2).最需要的健康教育方式是与医生护士交谈(66%)。结论:对手术等候期的患者家属应根据需求实施科学有效的健康教育,用恰当的方式及时提供家属想要了解的信息,使他们具有良好的应对能力和心理承受能力,在照顾患者的过程中为患者提供有效的支持系统。  相似文献   
5.
Babizhayev MA 《Life sciences》2006,78(20):2343-2357
Apart from genetically programmed cell aging, different external aggressors related to oxidative stress and lipid peroxidation (LPO) can accelerate the skin aging phenomenon. Oxidative stress associated with the formation of lipid peroxides is suggested to contribute to pathological processes in aging and systemic diseases known as the risk factors for cataract. Despite the fact that L-carnosine-related peptidomimetics N-acetylcarnosine (N-acetyl-beta-alanyl-L-histidine) (NAC) and carcinine (beta-alanylhistamine) are metabolically related to L-carnosine and have been demonstrated to occur in tissues of many vertebrates, including humans, these compounds were shown resistant toward enzymatic hydrolysis. A series of related biocompatible imidazole-containing peptidomimetics were synthesized in order to confer resistance to enzymatic hydrolysis and ex vivo improvement of protective antioxidative properties related to L-carnosine. The included findings revealed a greater role of N-acetylcarnosine (NAC) and carcinine ex vivo in the prolongation and potentiation of physiological responses to the therapeutical and cosmetics treatments with L-carnosine as antioxidant. 3-D molecular conformation studies proposed the antioxidant activity of peptidomimetics (carcinine, L-prolylhistamine, N-acetylcarnosine, L-carnosine) for metal ion binding, quenching of a number free radicals, and binding of hydroperoxide or aldehyde (including dialdehyde LPO products) in an imidazole-peroxide adducts. NAC can act as a time release (carrier) stable version of L-carnosine during application in ophthalmic pharmaceutical and cosmetics formulations which include lubricants. Carcinine, L-prolylhistamine show efficient deactivation of lipid hydroperoxides monitored by HPLC and protection of membrane phospholipids and water soluble proteins from the lipid peroxides-induced damages. This activity is superior over the lipophilic antioxidant vitamin E. The biologically significant applications of carnosine mimetics were patented by Dr. Babizhayev and the alliance Groups (WO 2004/028536 A1; WO 94/19325; WO 95/12581; WO 2004/064866 A1).  相似文献   
6.

Background

Ophthalmic acid (OPH), γ-glutamyl-L-2-aminobutyryl-glycine, a tripeptide analogue of glutathione (GSH), has recently captured considerable attention as a biomarker of oxidative stress in animals. The OPH and GSH biosynthesis, as well as some biochemical behaviors, are very similar. Here, we sought to investigate the presence of OPH in plants and its possible relationship with GSH, known to possess multiple functions in the plant development, growth and response to environmental changes.

Methods

HPLC-ESI-MS/MS analysis was used to examine the occurrence of OPH in leaves from various plant species, and flours from several plant seeds. Different types of oxidative stress, i.e., water, dark, paraquat, and cadmium stress, were induced in rye, barley, oat, and winter wheat leaves to evaluate the effects on the levels of OPH and its metabolic precursors.

Results

OPH and its dipeptide precursor, γ-glutamyl-2-aminobutyric acid, were found to occur in phylogenetically distant plants. Interestingly, the levels of OPH were tightly associated with the oxidative stress tested. Levels of OPH precursors, γ-glutamyl-2-aminobutyric acid and 2-aminobutyric acid, the latter efficiently formed in plants via biosynthetic pathways absent in the animal kingdom, were also found to increase during oxidative stress.

Conclusions

OPH occurs in plants and its levels are tightly associated with oxidative stress.

General significance

OPH behaves as an oxidative stress marker and its biogenesis might occur through a biochemical pathway common to many living organisms.  相似文献   
7.
PurposeTo evaluate the impact on dose distribution to eye organs-at-risk (eOARs) of a computed tomography (CT)-based treatment planning in eye plaque brachytherapy (EPB) treatment.MethodsWe analyzed 19 ocular melanoma patients treated with ruthenium-106 plaques to a total dose of 100 Gy to tumor apex using conventional central-axis-point dose calculation. Treatments were re-planned using the Plaque Simulator (PS) software implementing two different strategies: a personalized CT-eye-model (CT-PS) and a standard-eye-model (SEM-PS) defined by Collaborative Ocular Melanoma Study. Dice coefficient and Hausdorff distance evaluated the concordance between eye-bulb-models. Mean doses (Dmean) to tumor and eOARs were extracted from Dose-Volume-Histograms and Retinal-Dose-Area-Histogram. Differences between planning approaches were tested by Wilcoxon signed-rank test.ResultsIn the analyzed cohort, 8 patients (42%) had posterior tumor location, 8 (42%) anterior, and 3 (16%) equatorial. The SEM did not accurately described the real CT eye-bulb geometry (median Hausdorff distance 0.8 mm, range: (0.4–1.3) mm). Significant differences in fovea and macula Dmean values were found (p = 0.04) between CT-PS and SEM-PS schemes. No significant dosimetric differences were found for tumor and other eOARs. The planning scheme particularly affects the OARs closest to the tumor with a general tendency of SEM-PS to overestimate the doses to the OARs closest to the tumor.ConclusionThe dosimetric accuracy achievable with CT-PS EPB treatment planning may help to identify ocular melanoma patients who could benefit the most from a personalized eye dosimetry for an optimal outcome in terms of tumor coverage and eOARs sparing. Further research and larger studies are underway.  相似文献   
8.
Background and purpose: Hemodynamic parameters are important in the pathogenesis, evolution and rupture of intracranial aneurysm. Energy loss (EL) has been applied for the rupture risk prediction of artery aneurysms recently. We proposed a new EL and further investigate its effects on the rupture of aneurysms. Materials and methods: Sixty-four patient-specific ophthalmic aneurysm datasets were divided into ruptured and unruptured groups based on their clinical history. Based on patient-specific 3D-DSA data, realistic models were retrospectively reconstructed and then analyzed by using computational fluid dynamic method. Results: The flow field feature EL in ruptured cases was significantly higher than that in unruptured cases. The average wall shear stress (WSS) and the maximum WSS in ruptured cases were higher than those in unruptured cases. Modified pressure loss coefficient (PLCM) in ruptured cases was slight higher than that in unruptured cases but the difference has no statistical significance. Multivariate logistic regression analysis demonstrated flow field feature EL (p < 0.05) and the maximum WSS (p < 0.05) were the only independently significant variables to predict rupture of ophthalmic aneurysm. There were no differences in PLCM, the maximum oscillatory shear index (OSI), the average OSI and AR between the two groups. Conclusion: Flow field feature EL may be a reliable factor to predict the rupture risk of aneurysms.  相似文献   
9.
目的:研究康柏西普联合全视网膜光凝(panretinal photocoagulation,PRP)治疗糖尿病黄斑水肿(diabetic macular edema, DME)的疗效及安全性。方法:回顾性分析2016年4月到2018年4月本院接诊的DME患者238例,按照治疗方式的不同将其分成观察组及对照组。对照组采用PRP治疗,观察组则采用抗血管内皮生长因子(vascular endothelial growth factor, VEGF)药物康柏西普联合PRP实施治疗。比较两组患者治疗后的临床效果、手术前后视力和黄斑中心凹厚度的变化及预后情况。结果:治疗后,观察组的治疗效率为94.96%,较对照组(84.87%)显著升高(P0.05)。观察组术后视力明显高于手术前(P0.05),且显著高于对照组(P0.05);观察组术后黄斑中心凹厚度明显小于术前(P0.05),且显著小于对照组。观察组并发症发生率(3.36%)明显低于对照组(10.92%,P0.05)。结论:康柏西普联合PRP治疗DME患者的效果显著优于单用PRP治疗,且安全性更高。  相似文献   
10.
目的:探讨脑电双频指数(BIS)对靶控瑞芬太尼输注在小儿眼科手术中的指导意义。方法:择期小儿眼科手术80例,随机均分为(A组)BIS反馈调控瑞芬太尼组,(B组)根据经验用药组,比较两组中瑞芬太尼的用量,血流动力学以及苏醒时间。结果:A组瑞芬太尼用量明显低于B组(P<0.05),B组血流动力学,BIS值波动明显大于A组(P<0.05),B组苏醒时间明显短于A组(P<0.05)。结论:小儿眼科手术中,BIS反馈调控瑞芬太尼靶控输注(TCI)技术可降低瑞芬太尼用量,有助于判断全麻深度,指导麻醉用药。  相似文献   
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