bFGF诱导人胚视网膜色素上皮细胞转分化的研究

目的 探讨bFGF体外诱导早期人胚视网膜色素上皮（RPE）细胞转分化现象及其分子机制,为视网膜发育的进一步基础研究和临床RPE细胞移植奠定基础.方法 取4～6代人胚（6 w～10 w）RPE细胞,bFGF（20 ng/ml）诱导培养（4 d～6 d）后观察RPE细胞形态学的改变,用免疫细胞化学作转分化RPE细胞鉴定.RT-PCR分析转分化RPE细胞小眼畸形基因（MITF）的表达.结果 bFGF诱导培养后的人胚RPE细胞呈现类神经样细胞表型,不仅表达自身上皮细胞标记物角蛋白（Keratin）,同时还表达多种神经视网膜上皮细胞标记物（MAP2、GS、GFAP、Peripherin、Opsin,但不表达NCAM）;用RT-PCR方法没有检测到转分化RPE细胞MITF-A mRNA表达.结论 早期人胚RPE细胞的发育具有一定的可塑性,bFGF可以诱导早期人胚RPE细胞表达多种神经视网膜上皮细胞标记物,可能是通过抑制MITF-A的分子信号通路.     

Rolandic paroxysmal epilepsy: a long term study in 150 children

150 children with Rolandic paroxysmal epilepsy (RPE) aged 3 to 12 years were followed up clinically and by EEG for 16 years. Antiepileptic drugs were administered initially for 2 years and then suspended for 6–12 months. Treatment was resumed in the 29 patients who had seizures during the drug-free interval and was maintained for a further 5 years.80.6% of all patients were in clinical remission after the 2-year treatment period. Some patients had seizures while on drugs, others during the drug-free interval. Seizure frequency declined with age. No seizures occured after the age of 14 or in the 8 years following final discontinuation of drug therapy. The need for prolonged drug treatment is therefore questioned.

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Sommario 150 bambini affetti da Epilessia a Parossismi Rolandici, di età compresa tra i 3 e i 12 anni, sono stati tenuti sotto controllo clinico ed elettroencefalografico per un periodo di sedici anni.È stato effettuato un trattamento con farmaci antiepilettici per 2 anni. Dopo 6/12 mesi di wash-out farmacologico, in 29 pazienti che hanno manifestato crisi, la terapia farmacologica è stata ripristinata e mantenuta per 5 anni.Dopo i primi due anni di terapia, si è avuta una remissione clinica nell'80.6% dei casi. Alcuni pazienti hanno manifestato crisi durante l'assunzione della terapia, altri durante il periodo di wash-out. In ogni caso l'incidenza delle crisi diminuisce con il crescere dell'età dei pazienti. Al di sopra dei 14 anni non sono state registrate crisi, e l'osservazione durante gli otto anni successivi alla sospensione definitiva della terapia farmacologica non ha rivelato la comparsa di alcuna crisi.Viene quindi discussa la necessità di un trattamento farmacologico prolungato in corso di Epilessia a Parossismi Rolandici.

     

Hyperosmolarity response of ocular standing potential as a clinical test for retinal pigment epithelium activity normative data

The standing potential of the eye is decreased by intravenous administration of hypertonic solutions. This hyperosmolarity-induced response has been recorded in normal subjects by the use of electro-oculography (EOG) in the dark. An intravenous administration of Fructmanit^® (1.4 × 10³ mOsmol) (150 500ml, 2.37 9.70ml/kg, 0.08 0.36 ml/kg/min) was used to evoke the hyperosmolarity response. The amplitude of the response was expressed in percentage, V₀ – V_min/V₀ × 100, where V₀ is the base value of the EOG before administration of the hypertonic solution and V_min is a minimum EOG amplitude after administration. The distribution of the amplitude of the hyperosmolarity response was approximated by the normal distribution in normal subjects. The minimum, the maximum, the mean and the standard deviation of the amplitude of the hyperosmolarity response were respectively 34.2%, 52.3%, 42.6% and 4.6% in normal subjects. The normal range of the hyperosmolarity response would be 33.4 51.8% (M ± 2SD). The hyperosmolarity response, which originates mainly in the retinal pigment epithelium, is a useful new quantitative and specific test of the activity of the retinal pigment epithelium in clinical practice.     

Personal protective equipment related skin reactions in healthcare professionals during COVID‐19

Since the outbreak of COVID‐19 pandemic, clinicians have had to use personal protective equipment (PPE) for prolonged periods. This has been associated with detrimental effects, especially in relation to the skin health. The present study describes a comprehensive survey of healthcare workers (HCWs) to describe their experiences using PPE in managing COVID‐19 patients, with a particular focus on adverse skin reactions. A 24‐hour prevalence study and multi‐centre prospective survey were designed to capture the impact of PPE on skin health of hospital staff. Questionnaires incorporated demographics of participants, PPE type, usage time, and removal frequency. Participants reported the nature and location of any corresponding adverse skin reactions. The prevalence study included all staff in intensive care from a single centre, while the prospective study used a convenience sample of staff from three acute care providers in the United Kingdom. A total of 108 staff were recruited into the prevalence study, while 307 HCWs from a variety of professional backgrounds and demographics participated in the prospective study. Various skin adverse reactions were reported for the prevalence study, with the bridge of the nose (69%) and ears (30%) being the most affected. Of the six adverse skin reactions recorded for the prospective study, the most common were redness blanching (33%), itchiness (22%), and pressure damage (12%). These occurred predominantly at the bridge of the nose and the ears. There were significant associations (P < .05) between the adverse skin reactions with both the average daily time of PPE usage and the frequency of PPE relief. The comprehensive study revealed that the use of PPE leads to an array of skin reactions at various facial locations of HCWs. Improvements in guidelines are required for PPE usage to protect skin health. In addition, modifications to PPE designs are required to accommodate a range of face shapes and appropriate materials to improve device safety.     

人参皂甙Rg1、Rb1和维生素E对氧化损伤的牛RPE细胞p53表达的影响

目的：检验氧化损伤的牛RPE细胞是否存在p53基因表达的变化和人参皂甙Rg1、Rb1和维生素E对其的影响,以期进一步研究RPE细胞氧化损害的机理.方法：建立牛RPE细胞氧化损伤模型,原位杂交技术测定RPE细胞p53mRNA的表达,免疫组化技术测定p53蛋白表达.结果：p53蛋白表达阳性的牛RPE细胞的细胞核染成黄色,与次黄嘌吟／黄嘌吟氧化酶（HX／XO）组p53蛋白阳性的细胞数相比较,正常对照组,Rg1（0.1mg.L-1）组及VitE（10mg.L-1）组存在显著性差异（P＜0.05）,而与Rb1（10mg.L-1）组无显著性差异.原位杂交法测定P53mRNA表达,牛RPE细胞P53mRNA表达阳性可在细胞浆内见到位于细胞周边部的蓝紫色絮状物,分别与HX／XO组阳性的细胞相比较,正常对照组,Rg1组及VitE组存在显著性差异（P＜0.05）,而与Rb1组无显著性差异.结论：氧化损伤可导致基因P53mRNA及其蛋白在RPE细胞内的表达明显增加.人参皂甙Rg1和VitE对抗氧自由基对RPE细胞损伤的机制可能是通过清除氧自由基,影响凋亡基困p53的表达,从而有效地抑制氧自由基对RPE细胞的损伤.     

Immunocytochemical Study of Cells in the Vitreous of Proliferative Virteoretretinopathy

Purpose: To identify the cellular components of vitreous samples obtained during vit-rectomy for proliferative vitreoretinopathy(PVR).Methods: With the use of three intermediate filament (IF) proteins, vimentin, glialfibrillary acidic protein (GFAP), and cytokeratin (CK), cytocentrifuge slides of 14fresh vitreous aspirates were detected with immunohistochemical technique.Results: All the specimens contained epithelial-like proliferative cells with or withoutpigment and some membrane-like pieces. Immunocytochemical staining showed that76.0-90.0% cells stained for CK, 17.4-29.6% cells expressed GFAP, and 80.1-91.0% cells were positive for vimentin.Conclusions : Majority of cells in the vitreous samples originated from retinal pigmentepithelial cells (RPE) and glial cells in PVR. Expression of IF proteins may be determinedby tissue of origin and local microenvironment. Eye Science 1999 ; 15; 13 - 16.     

视频显示终端作业工间休息制度的探讨

目的探讨不同类型的视频显示终端(VDT)作业工间休息制度。方法14名大学生作为志愿受试者在计算机上阅读短文各自15、30和60min,记录分析了受试者不同阅读时段的Cooper-Harper量表评分、正确率、阅读速度、阅读效率、自感用力度(RPE)评分等指标。另外,让46名大学生在计算机前输入随机数字60min,每10min自动记录1次输入速度和正确率。结果随着阅读时间的延长,Cooper-Harper量表评分、RPE评分有逐渐增加的趋势,正确率、阅读速度有下降的趋势,但差异无显著性;60min阅读与15min相比,阅读效率下降。在60min内,输入数字的速度随时间的延长而逐渐增加;而正确率呈现出一种逐渐降低的趋势,但差异不显著。结论在60min内,阅读效率下降,而输入数字的速度逐渐增加;不同类型的VDT作业,作业者的作业能力有不同的变动规律,需要设置不同的工间休息制度。     

A Novel KCNJ13 Nonsense Mutation and Loss of Kir7.1 Channel Function Causes Leber Congenital Amaurosis (LCA16)

Mutations in the KCNJ13 gene that encodes the inwardly rectifying potassium channel Kir7.1 cause snowflake vitreoretinal degeneration (SVD) and leber congenital amaurosis (LCA). Kir7.1 controls the microenvironment between the photoreceptors and the retinal pigment epithelium (RPE) and also contributes to the function of other organs such as uterus and brain. Heterologous expressions of the mutant channel have suggested a dominant‐negative loss of Kir7.1 function in SVD, but parallel studies in LCA16 have been lacking. Herein, we report the identification of a novel nonsense mutation in the second exon of the KCNJ13 gene that leads to a premature stop codon in association with LCA16. We have determined that the mutation results in a severe truncation of the Kir7.1 C‐terminus, alters protein localization, and disrupts potassium currents. Coexpression of the mutant and wild‐type channel has no negative influence on the wild‐type channel function, consistent with the normal clinical phenotype of carrier individuals. By suppressing Kir7.1 function in mice, we were able to reproduce the severe LCA electroretinogram phenotype. Thus, we have extended the observation that Kir7.1 mutations are associated with vision disorders to include novel insights into the molecular mechanism of disease pathobiology in LCA16.     

Patient-specific induced pluripotent stem cells (iPSCs) for the study and treatment of retinal degenerative diseases

Vision is the sense that we use to navigate the world around us. Thus it is not surprising that blindness is one of people's most feared maladies. Heritable diseases of the retina, such as age-related macular degeneration and retinitis pigmentosa, are the leading cause of blindness in the developed world, collectively affecting as many as one-third of all people over the age of 75, to some degree. For decades, scientists have dreamed of preventing vision loss or of restoring the vision of patients affected with retinal degeneration through drug therapy, gene augmentation or a cell-based transplantation approach. In this review we will discuss the use of the induced pluripotent stem cell technology to model and develop various treatment modalities for the treatment of inherited retinal degenerative disease. We will focus on the use of iPSCs for interrogation of disease pathophysiology, analysis of drug and gene therapeutics and as a source of autologous cells for cell transplantation and replacement.