人肝癌细胞遗传印记基因PEG10印记状态不受DMR甲基化调控

目的探讨人肝癌细胞遗传印记基因(genetic imprinted gene)PEG10差异性甲基化区(differntially DNA methylated region,DMR)甲基化状态在其印记调控中的作用。方法以单核苷酸多态性(single nucleotide polymorphisms,SNP)位点为等位基因标记,分析人肝癌HepG2细胞PEG10印记状态;采用RT-PCR、免疫组化及Western-blot检测PEG10表达水平;重亚硫酸盐修饰DNA测序法分析PEG10-DMR甲基化状态;再应用甲基基团供体S-腺苷蛋氨酸(S-adenosyl-L-methionine,SAM)及DNA甲基转移酶抑制剂5-氮杂胞苷(5-azacytidine,5-azaC)在体外及荷瘤裸鼠体内调控HepG2细胞PEG10-DMR甲基化状态,观察PEG10-DMR甲基化状态改变对PEG10印记状态及表达水平的影响。结果遗传印记基因PEG10在HepG2细胞呈双等位基因表达的印记丢失。与正常肝细胞HL7702相比,其PEG10-DMR甲基化水平显著升高。调控PEG10-DMR甲基化水平可改变PEG10的表达水平,但对其印记状态无影响。结论 PEG10-DMR甲基化不参与人肝癌细胞PEG10的印记调控,但可调控其表达水平。     

超声内镜引导下经皮内镜胃造瘘术的临床应用

内镜辅助下经皮胃造瘘术（percutaneousendoscopicgastrostomy,PEG）已广泛应用于需长期鼻饲患者的胃造瘘胃营养管或空肠营养管置入。尽管如此,在实际操作中仍有部分患者因腹壁过厚、胃腔体表投影无法显现或位置变异等原因导致PEG失败。此外,PEG所致的胃一结肠瘘、实质性脏器损伤等并发症,也时有报道。为进一步提高PEG成功率,减少并发症,我们将传统PEG操作技术改进为超声内镜引导下胃造瘘术（EUS—PEG）,克服了上述困难,取得了满意的效果．     

Single endoscopist-performed percutaneous endoscopic gastrostomy tube placement

AIM: To investigate whether single endoscopist-performed percutaneous endoscopic gastrostomy (PEG) is safe and to compare the complications of PEG with those reported in the literature. METHODS: Patients who underwent PEG placement between June 2001 and August 2011 at the Baskent University Alanya Teaching and Research Center were evaluated retrospectively. Patients whose PEG was placed for the first time by a single endoscopist were enrolled in the study. PEG was performed using the pull method. All of the patients were evaluated for their indications for PEG, major and minor complications resulting from PEG, nutritional status, C-reactive protein (CRP) levels and the use of antibiotic treatment or antibiotic prophylaxis prior to PEG. Comorbidities, rates, time and reasons for mortality were also evaluated. The reasons for PEG removal and PEG duration were also investigated. RESULTS: Sixty-two patients underwent the PEG procedure for the first time during this study. Eight patients who underwent PEG placement by 2 endoscopists were not enrolled in the study. A total of 54 patients were investigated. The patients’ mean age was 69.9 years. The most common indication for PEG was cerebral infarct, which occurred in approximately two-thirds of the patients. The mean albumin level was 3.04 ± 0.7 g/dL, and 76.2% of the patients’ albumin levels were below the normal values. The mean CRP level was high in 90.6% of patients prior to the procedure. Approximately two-thirds of the patients received antibiotics for either prophylaxis or treatment for infections prior to the PEG procedure. Mortality was not related to the procedure in any of the patients. Buried bumper syndrome was the only major complication, and it occurred in the third year. In such case, the PEG was removed and a new PEG tube was placed via surgery. Eight patients (15.1%) experienced minor complications, 6 (11.1%) of which were wound infections. All wound infections except one recovered with antibiotic treatment. Two patients had bleeding from the P     

Is percutaneous endoscopic gastrostomy tube placement safe in patients with ventriculoperitoneal shunts？

AIM： To investigate whether percutaneous endoscopic gastrostomy （PEG） tube placement is safe in patients with ventriculoperitoneal （VP） shunts. METHODS： This was a retrospective study of all patients undergoing PEG insertion at our institution between June 1999 and June 2006. Post-PEG complications were compared between two groups according to the presence or absence of VP shunts. VP shunt infection rates, the interval between PEG placement and VP shunt catheter insertion, and long- term follow-up were also investigated. RESULTS： Fifty-five patients qualified for the study. Seven patients （12.7%） had pre-existing VP shunts. All patients received prophylactic antibiotics. The complication rate did not differ between VP shunt patients undergoing PEG （PEG/VP group） and non-VP shunt patients undergoing PEG （control group） [1 （14.3%） vs 6 （12.5%）, P = 1.000]. All patients in the PEG/VP group had undergone VP shunt insertion prior to PEG placement. The mean interval between VP shunt insertion and PEG placement was 308.7 d （range, 65-831 d）. The mean follow-up duration in the PEG/VP group was 6.4 mo （range, 1-15 mo）. There were no VP shunt infections, although one patient in the PEG/VP group developed a minor peristomal infection during follow-up. CONCLUSION： Complications following PEG placement in patients with VP shunts were infrequent in this study.     

Split-dose menthol-enhanced PEG vs PEG-ascorbic acid for colonoscopy preparation

AIM:To compare the efficacy and palatability of 4L polyethylene glycol electrolyte(PEG)plus sugar-free menthol candy(PEG+M)vs reduced-volume 2 L ascorbic acid-supplemented PEG(Asc PEG).METHODS:In a randomized controlled trial setting,ambulatory patients scheduled for elective colonoscopy were prospectively enrolled.Patients were randomized to receive either PEG+M or Asc PEG,both splitdosed with minimal dietary restriction.Palatability was assessed on a linear scale of 1 to 5(1=disgusting;5=tasty).Quality of preparation was scored by assignment-blinded endoscopists using the modified Aronchick and Ottawa scales.The main outcomes were the palatability and efficacy of the preparation.Secondary outcomes included patient willingness to retake the same preparation again in the future and completion of the prescribed preparation.RESULTS:Overall,200 patients were enrolled(100patients per arm).PEG+M was more palatable than Asc PEG(76%vs 62%,P=0.03).Completing the preparation was not different between study groups(91%PEG+M vs 86%Asc PEG,P=0.38)but more patients were willing to retake PEG+M(54%vs 40%respectively,P=0.047).There was no significant difference between PEG+M vs Asc PEG in adequate cleansing on both the modified Aronchick(82%vs77%,P=0.31)and the Ottawa scale(85%vs 74%,P=0.054).However,PEG+M was superior in the left colon on the Ottawa subsegmental score(score0-2:94%for PEG+M vs 81%for Asc PEG,P=0.005)and received significantly more excellent ratings than Asc PEG on the modified Aronchick scale(61%vs 43%,P=0.009).Both preparations performed less well in afternoon vs morning examinations(inadequate:29%vs 15.2%,P=0.02).CONCLUSION:4 L PEG plus menthol has better palatability and acceptability than 2 L ascorbic acidPEG and is associated with a higher rate of excellentpreparations;Clinicaltrial.gov identifier:NCT01788709.     

遗传印记基因PEG10沉默对人肝癌细胞Wnt/β-catenin信号转导通路的影响

目的观察靶向封闭遗传印记基因PEG10对人肝癌细胞(HepG2)Wnt/β-catenin信号转导通路的影响,探讨PEG10促进肝癌形成的可能机制。方法设计针对PEG10基因的shRNA,体外转录制备shRNA后利用脂质体转染技术转染肝癌细胞株HepG2,RT-PCR检测PEG10、β-catenin(CTNNB1)、WNT1基因mRNA水平,应用免疫组化技术检测其蛋白表达水平。结果转染PEG10-shRNA后HepG2细胞PEG10 mRNA水平下降65.6%,其蛋白表达水平减少60.9%;同时,β-catenin(CTNNB1)、WNT1基因mRNA水平随之分别下降52.5%、96.1%,蛋白表达水平分别减少94.3%、63.2%。结论靶向封闭PEG10可下调肝癌细胞Wnt/β-catenin信号通路关键因子β-catenin(CTNNB1)、WNT1表达水平。PEG10对肝癌的促进作用可能部分与其影响Wnt/β-catenin通路有关。     

胃镜下经皮胃造瘘的临床应用

1980 年非手术经皮内镜下胃造瘘术(percutaneous endoscopic gastrostomy, PEG)被介绍应用于临床, 其优点是操作简便、并发症少. 近30年来, PEG临床应用的范围不断扩展,越来越受到重视. 该项技术已在欧美、日本等国家替代外科胃造瘘. 目前PEG已经成为需要长期肠内营养支持患者的首选方法. 本文介绍了PEG技术, PEG的适应证、禁忌证、并发症以及处理方法.     

PEG10在人胃癌组织中的表达及其临床意义

目的研究印记基因10(paternally expressed gene 10,PEG10)在胃癌组织中的表达情况,并探讨PEG10与胃癌的临床病理特征及预后的关系。方法利用免疫组化技术检测84例胃癌患者癌组织、癌旁组织及10例正常胃组织中PEG10表达情况,并结合其临床资料分析其临床意义。结果 84例胃癌组织中有63例(75.00%)PEG10阳性表达,相应癌旁组织中有50例(59.52%)PEG10阳性表达,差异有统计学意义(χ~2=4.601,P=0.032),而10例正常胃组织PEG10均阴性表达。PEG10的阳性表达与淋巴结转移(χ~2=6.115,P=0.013)及肿瘤的TNM分期相关(χ~2=7.710,P=0.007)。Cox多因素回归分析表明,PEG10阳性表达是患者预后不良的独立危险因素(P=0.03)。结论 PEG10在胃癌组织中高表达,在癌旁组织中相对低表达,而在正常胃组织中不表达。PEG10的表达与淋巴结转移及TNM分期相关。PEG10对胃癌患者预后判断有一定的价值,可能成为一个新的胃癌分子标志物。     

经皮内镜下胃造瘘在重度颅脑损伤患者治疗中的应用

目的评价内镜下经皮胃造瘘(PEG)在重度颅脑损伤患者临床治疗中的应用价值。方法对32例行PEG术的重度颅脑损伤后患者进行回顾性分析,采用PEG前后自身对照的方法比较其营养水平及肺部感染的发生率。结果 32例患者均成功实施PEG术,术后营养水平显著改善,肺部感染控制良好,临床治疗费用大幅降低,且未发生严重的并发症。结论 PEG是一种安全、高效、价廉的方法,对重症颅脑损伤患者有较好应用价值。     

肝脏特异性表达人遗传印记基因PEG10转基因载体的构建和鉴定

目的构建小鼠肝脏特异性表达人遗传印记基因PEG10的转基因载体pALB—PEG10-EGFP，为制备转基因小鼠做准备。方法RT—PCR扩增PEG10基因cDNA序列，克隆入T载体进行酶切、测序鉴定，后将其定向克隆至真核表达载体pALB．EGFP中ALB的下游，构建转基因载体pALB—PEG10-EGFP；在Lipofectamine介导下转染L02细胞，经G418抗性筛选，挑选阳性克隆并扩大培养；采用RT—PCR、Westernb1ot、免疫细胞化学等方法分析PEG10在L02细胞中的表达和细胞内定位。结果酶切和测序结果表明pALB—PEG10-EGFP构建成功；稳定转染后的L02表达有PEG10的mRNA及蛋白，且主要定位于胞浆。结论重组体pALB—PEG10-EGFP的构建初步奠定了转基因小鼠制备的基础。     

经皮内镜胃造瘘和小肠造瘘术的临床应用

目的 探讨经皮内镜胃造瘘术(PEG)和经皮内镜小肠造瘘术(PEJ)的临床应用价值。方法 1996—06／2002—08 PEG和PEJ共治疗24例病人，其中13例行PEG胃肠营养；11例行PEG胃肠减压加PEJ小肠内营养。结果 21例共行PEG、PEG加PEJ28例次，其中PEG17例次(4例行造瘘管置换)、PEG加PEJ11例次，手术成功率100％。2／28例次出现造瘘管周围皮下感染。所有患者造瘘管置入后营养迅速恢复，停止静脉补液。24例病人随访1～48个月无严重并发症发生。结论PEG和PEJ是作为胃肠减压和肠内营养替代鼻饲的一种新的治疗方法，具有安全、有效、降低医疗费用和并发症少等优点。     

印迹基因PEG10在胃癌中的表达及其与幽门螺杆菌感染的关系

目的探讨印迹基因PEG10在胃癌组织中的表达特点及其与幽门螺杆菌（Hp）感染的关系。方法采用逆转录聚合酶链反应（RT-PCR）检测40例胃癌、癌旁组织中印迹基因PEG10的mRNA水平;采用免疫组织化学染色技术及Warthin-Starry银染法检测42例胃癌、癌旁组织及6例正常胃组织中PEG10蛋白的表达及Hp感染情况。结果RT-PCR结果显示20例胃癌组织中9例（45.0%）PEG10mRNA表达,对应的癌旁组织仅有2例（10%）表达;免疫组织化学染色结果显示42例胃癌组织中22例（52.38%）PEG10蛋白表达阳性,对应的癌旁组织仅有5例（11.90%）PEG10蛋白表达阳性,正常胃组织无PEG10蛋白表达;Hp银染法结果显示42例胃癌组织中25例（59.52%）为Hp感染阳性,癌旁组织20例（47.62%）Hp感染阳性;22例PEG10阳性表达胃癌组织中20例Hp感染阳性。结论PT-PCR结果与免疫组织化学染色结果具有一致性,即PEG10mRNA及蛋白在胃癌组织和癌旁组织中的表达率比较差异有显著性（P〈0.05）;PEG10在胃癌组织中的表达与Hp感染呈正相关（P〈0.05）。     

Laparoscopy-assisted percutaneous endoscopic gastrostomy enables enteral nutrition even in patients with distorted anatomy

AIM:To analyzed whether laparoscopy-assisted percutaneous endoscopic gastrostomy(PEG)could be a valuable option for patients with complicated anatomy.METHODS:A retrospective analysis of twelve patients(seven females,five males;six children,six young adults;mean age 19.2 years)with cerebral palsy,spastic quadriparesis,severe kyphoscoliosis and interposed organs and who required enteral nutrition(EN)due to starvation was performed.For all patients,standard PEG placement was impossible due to distorted anatomy.All the patients qualified for the laparoscopyassisted PEG procedure.RESULTS:In all twelve patients,the laparoscopy-assisted PEG was successful,and EN was introduced four to six hours after the PEG placement.There were no complications in the perioperative period,either technical or metabolic.All the patients were discharged from the hospital and were then effectively fed using bolus methods.CONCLUSION:Laparoscopy-assisted PEG should become the method of choice for gastrostomy tube placement and subsequent EN if PEG placement cannot be performed safely.     

Bowel preparation prior to colonoscopy:A continual search for excellence

Bowel preparation prior to colonoscopy is essential to maximize the benefits of colonoscopy.Numerous bowel preparations have been studied,ranging from 4 L polyethylene glycol(PEG) to split-dose regimens to 2 L PEG with an adjunct laxative(senna,bisacodyl,ascorbic acid).Due to the large volume of PEG required for adequate bowel preparation,many studies have focused on reducing this large volume to only 2 L PEG with the addition of an adjunct.Recently,a randomized controlled trial by Tajika et al showed that the addition of mosapride to only 1.5 L PEG was non-inferior to mosapride and 2 L PEG for bowel cleansing but did provide improvements in patient tolerance.This study offers yet another potential bowel preparation for patients undergoing colonoscopy and may trigger further studies with 1.5 L PEG with an adjunct.In this letter,we discuss the current state of bowel preparation prior to colonoscopy and offer information to guide clinicians on choosing the appropriate bowel preparation for their patients.     

经皮内镜下胃造瘘术在鼻咽癌病人中的临床应用

目的评价经皮内镜下胃造瘘术(PEG)对鼻咽癌病人营养支持的应用价值。方法回顾分析我院24例行PEG术的鼻咽癌病人。手术适应症,手术步骤,术前准备,并发症和有效性均有记录。结果24例病人成功接受PEG术,未发生严重并发症,病人的状况得到改善,其中4例患者已拔管。结论PEG术可避免鼻咽癌病人营养状况的恶化,同时提高其生活质量,是一种有效、微创、安全和简便的方法。     

聚乙二醇与乳果糖治疗肝性脑病患者疗效和安全性的Meta分析

目的 比较聚乙二醇(PEG)与乳果糖治疗肝性脑病(HE)患者的疗效和安全性。方法 利用计算机在 PubMed、EMbase、Cochrane、万方数据库、中国知网中检索自建库至 2019年11月20日期间关于PEG与乳果糖治疗HE患者的随机对照试验,选取符合纳入条件的文献并对其进行质量评价。应用RevMan 5.3 软件进行Meta分析。结果 纳入8项随机对照研究,包括PEG处理组249例和乳果糖处理组244例患者。Meta分析结果显示,PEG组不良反应发生率为12.9%,显著低于乳果糖组的27.4%(P＜0.0001);PEG组24 h HESA评分改善率为91.5%,显著高于乳果糖组的65.5%(P＜0.0001);PEG组和乳果糖组住院日分别为,治疗前后血氨分别下降了。结论 PEG较乳果糖治疗HE患者不良反应少,能更快地降低患者24 h HESA评分,缩短住院日,其临床应用值得进一步观察。     

PEG10表达与原发性肝癌预后相关性分析

目的检测PEG10在原发性肝癌(PHC)组织中表达的情况,探讨其与临床病理参数的关系及对肝癌预后的临床意义。方法应用免疫组织化学方法(SP法)检测58例PHC患者肝组织中PEG10的表达情况,并分析PEG10与PHC临床病理特征及预后的关系。结果 58份PHC标本中44份PEG10阳性,其中"+"16份、"++"13份和"+++"15份。平均随访时间为40.5 m,至随访结束时共有23例(39.7%)患者死亡;所有患者中位生存时间为31 m,PEG10表达为"-"、"+"、"++"、"+++"的中位生存时间分别为57、34、27和15 m,不同PEG10表达组间生存率差异有统计学意义(P=0.000);PEG10在女性、晚期病例、术前AFP200 ng/mL、微血管侵犯、低分化肝癌患者肿瘤组织中表达更高(P0.05),而与患者年龄、肿瘤直径、病因无关(P0.05);早期复发病例中PEG10阳性比例明显高于阴性(P0.05),而晚期复发病例组间无明显差异(P0.05)。PEG10预测PHC复发的诊断特异度77.5%,敏感度为38.9%,准确率为65.5%,多因素COX模型中AJCC分期、微血管侵犯、病因和PEG10表达是影响PHC预后的危险因素(P0.05),其中PEG10阳性的HR达6.724。结论 PEG10对PHC预后具有很好的评估价值,但是其特异性高而敏感性不高,需要联合其他指标作出综合评价。     

人遗传印记基因PEG10重组真核表达质粒的构建及其在转染细胞株中的表达

目的构建人遗传印记基因PEG10的全长表达基因质粒,观察PEG10的过表达对人正常肝细胞及其非肝脏来源的对照细胞的作用。方法将PEG10基因全长cDNA直接连入真核细胞表达质粒pcDNA3．1hisC中,以脂质体介导的方法将该表达质粒pcDNA3．1hisC-PEG10转染入人正常肝细胞及其对照细胞,采用RT-PCR、Western blot、MTT、TUNEL等方法分析PEG10基因在正常人肝细胞及其对照细胞中的表达和功能。结果限制性酶切及DNA测序结果均说明所构建质粒为PEG 10全长表达质粒。该质粒经过稳定筛选后稳定表达于细胞内,促进人肝细胞的生长,抑制其凋亡,但对非肝脏来源的对照组细胞没有明显影响。结论PEG10全长表达质粒的构建为进一步研究PEG10基因的效应和机制提供了有利的工具,研究结果显示PEG10基因可以促进人正常胚肝细胞增殖并抑制其凋亡,但对非肝脏来源的对照组细胞人胚肾细胞株293细胞没有明显效应。     

PEG-5000修饰后假丝酵母尿酸酶的基本特性

目的研究天然尿酸酶与PEG化尿酸酶的基本特性,为治疗高尿酸血症相关疾病药物做基础研究。方法用相对分子量5kD,活化基团为羟基琥珀亚氨的PEG作为专一性修饰剂对尿酸酶进行修饰,采用常规酶学分析方法,分别研究天然尿酸酶与PEG化尿酸酶的动力学参数,并比较修饰前后对抑制剂黄嘌呤的敏感性、最适温度、最适pH值、37℃时的稳定性以及在体半衰期等方面的差异。结果经PEG修饰后尿酸酶最适温度由30℃升为35℃,最适pH无改变仍为pH8.7;在37℃水浴下,24h后活性保留由40%增至70%,酶稳定性提高,体内半衰期由45min延长至11h;测定尿酸酶和PEG化尿酸酶的Km分别为32.40、36.34μmol/L,黄嘌呤对尿酸酶与PEG化尿酸酶抑制常数分别为4.72、11.30μmol/L。结论假丝酵母尿酸酶经PEG5kD修饰后有药用潜力。     

内镜下经皮胃造瘘对老年患者生活质量的影响

目的:评价内镜下经皮胃造瘘(PEG)在老年患者的应用、安全性及对生活质量的影响.方法:对32例PEG老年患者进行回顾性分析,采用同组对照的方法比较PEG与鼻胃管饲对患者的影响.结果:32例老年患者均在局麻下成功进行了PEG,仅1例发生造瘘口周围皮肤感染,抗生素治疗后短期内恢复.PEG较鼻胃管饲患者更易于接受,导管不易堵塞,能降低吸入性肺炎及反流性食管炎(15.6% vs 46.8%,P＜0.05)的发生率,提高生活质量.结论:PEG是一种安全有效的治疗方法,较鼻胃管饲能明显降低吸入性肺炎、反流性食管炎的发生率.