Vertical ridge augmentation by expanded-polytetrafluoroethylene membrane and a combination of intraoral autogenous bone graft and deproteinized anorganic bovine bone (Bio Oss)

Objective: To evaluate, from a histological and histomorphometrical perspective, the efficacy of a 1 : 1 mixture of deproteinized bovine bone mineral (DBBM) and autogenous bone graft associated with an expanded‐polytetrafluoroethylene (e‐PTFE) membrane for vertical ridge augmentation in the human. Material and methods: Seven patients with 10 surgical sites requiring vertical ridge augmentation of partially edentulous lower jaws were included in the study. The vertical augmentation procedure was performed combining a titanium‐reinforced e‐PTFE Gore‐Tex membrane with a composite graft consisting of a 1 : 1 ratio of DBBM (Bio‐Oss) and autogenous bone. Twenty‐seven Branemark implants have been inserted. Eleven biopsies from the regenerated area were analyzed histologically and histomorphometrically. Results: The healing period was uneventful in nine surgical sites. In one site the membrane showed an exposure after 3 months. At the abutment connection, all implants appeared stable and submerged by a hard regenerated tissue clinically similar to bone. The histological analysis showed new bone formation and ongoing remodelling of the autogenous bone and the DBBM particles. Conclusions: The findings from the present clinical and histological study support the use of a 1 : 1 combination of DBBM and autogenous bone chips for vertical ridge augmentation by means of guided bone regeneration techniques. The regenerated bone may lead to proper osseointegration of a dental implant inserted at the time of the regenerative procedure or after a healing period of at least 6 months. DBBM undergoes very slow resorption and substitution with new bone. Furthermore, long‐term clinical studies are needed to confirm the positive effect of DBBM in enhancing the lasting stability of the vertically augmented bone.     

活体情况下评价载脂蛋白A1对小鼠视网膜血管生成的影响

用眼底照相及荧光造影探讨载脂蛋白A1（apoA1）正常生理状态下及缺氧状态下对小鼠视网膜血管生长情况的影响。     

鸟苷酸环化酶C在重症急性胰腺炎大鼠相关性肠损伤中的变化

目的 探讨鸟苷酸环化酶C（GC-C）在重症急性胰腺炎（SAP）相关性肠损伤中的变化规律及作用。方法（1）36只成年雄性SD大鼠用随机数字表法分为假手术组（n=18,SO组,开腹后仅翻动胰腺数次后关腹）和重症急性胰腺炎组[n=18,SAP组,开腹后经胰胆管逆行微量泵入5%牛磺胆酸钠（0.1 mL/100 g）制备SAP模型]。各组根据用药时间再次随机分为12 h组,24 h组和48 h 组（n=6）。于建模后12、24、48 h分批处死大鼠收集结肠组织进行免疫蛋白印迹、免疫组织化学和RT-PCR实验明确GC-C在SAP相关性肠损伤中的变化规律,选取GC-C表达最低的时间点作为肠损伤最严重的大概时间点,即作为干预时间点进行后续实验;（2）18只成年雄性SD大鼠用随机数字表法分为SO组（n=6,处理方法同前）、SAP组（n=6,处理方法同前）和Linaclotide组 [n=6,诱导SAP后立即用GC-C激动剂利那洛肽（Linaclotide）水溶液（10 μg/kg/d）灌胃1次]。根据第一部分实验结果,选取12h节点进行检测。以HE染色评估胰腺与结肠病理改变;ELISA法测定血清中淀粉酶（AMY）、二胺氧化酶（DAO）、D-乳酸（DLac）和TNF-α浓度;通过RT-PCR、免疫蛋白印迹法、免疫组织化学染色法和透射电镜检测结肠组织中GC-C和紧密连接蛋白Claudin-1的表达。结果 GC-C在SAP组大鼠结肠中表达显著降低,于SAP建模后12 h表达最低（P<0.05）,但随着时间推移GC-C表达逐渐升高。而结肠中Claudin-1表现出相似的趋势。与SO组相比,SAP组和Linaclotide组结肠表现为不同程度的粘膜不连续、间质水肿及炎性细胞浸润,病理学评分均升高（P<0.05）;血清淀粉酶、二胺氧化酶、D-乳酸和TNF-α均显著升高（P< 0.05）;结肠中GC-C和Claudin-1表达下降。与SAP组相比,Linaclotide组结肠组织病理评分降低,血清中上述各因子水平降低,而结肠组织中GC-C和Claudin-1表达水平升高。结论 GC-C在SAP相关性肠损伤中呈现出先降低后升高的表达趋势,于诱导SAP后12 h表达最低;通过激活GC-C可以提高GC-C和Claudin-1的表达水平并缓解肠道损伤,表明GC-C或许通过调节紧密 连接蛋白的表达来维持肠屏障功能的完整性。     

产黑普氏菌破坏上皮屏障紧密连接在口腔扁平苔藓发病机制中的作用

目的探索产黑普氏菌（Prevotella melaninogenica, Pm）侵入口腔扁平苔藓（oral lichen planus, OLP）病损组织的可能机制。方法收集OLP患者病损组织和正常黏膜组织,应用免疫组织化学染色检测闭锁小带蛋白-1（zonula occludin-1, ZO-1）和连接黏附分子-1（junctional adhesion molecule-1, JAM-1）的表达。将Pm与人口腔角质形成细胞（human oral keratinocytes, HOK）共培养,通过Transwell小室实验检测荧光素异硫氰酸酯-葡聚糖4KD（FITC-dextran 4KD, FD4）的渗透量,观察Pm对HOK上皮屏障功能的影响,并采用qPCR检测ZO-1和JAM-1的表达改变。结果OLP患者病损组织中ZO-1、JAM-1的表达显著低于正常组织（P<0.01,P<0.0001）。FD4的渗透量随Pm浓度增加而增加（P<0.05）。Pm与HOK细胞共培养后,ZO-1、JAM-1表达均显著减少（P<0.005;P<0.05）,并随着Pm浓度增加或时间延长而降低。结论Pm可能通过抑制紧密连接蛋白ZO-1、JAM-1的表达而破坏OLP上皮组织屏障,从而侵入上皮组织导致慢性炎症,在口腔扁平苔藓发生发展中起到重要作用。     

奥曲肽联合白蛋白对重症急性胰腺炎患者肠黏膜屏障功能的影响

目的分析奥曲肽联合白蛋白治疗重症急性胰腺炎患者的临床效果。方法选取2017年4月至2018年6月本院收治80例重症急性胰腺炎患者作为研究对象,采用随机数字表法分为观察组和对照组,每组40例。对照组患者采用常规治疗+奥曲肽,观察组采用常规治疗+奥曲肽+白蛋白。比较两组患者治疗后肠黏膜屏障功能[二胺氧化酶(DAO)、D-乳酸、内毒素]指标变化,同时比较临床相关指标改善情况。结果治疗前,两组患者DAO、D-乳酸、内毒素水平比较差异无统计学意义;治疗后,观察组患者DAO、D-乳酸、内毒素水平均低于对照组,差异有统计学意义(t=7.011、14.091、6.034,P均=0.000);观察组患者腹痛消失时间、退热时间、血淀粉酶恢复时间、住院时间均短于对照组,差异有统计学意义(t=2.952、4.314、3.380、3.932,P=0.004、0.000、0.001、0.000)。结论奥曲肽联合白蛋白治疗重症急性胰腺炎患者临床效果显著,可有效改善患者临床症状,缩短住院时间,促进肠黏膜屏障功能恢复。     

Contact lens-related corneal infection: Intrinsic resistance and its compromise

Contact lenses represent a widely utilized form of vision correction with more than 140 million wearers worldwide. Although generally well-tolerated, contact lenses can cause corneal infection (microbial keratitis), with an approximate annualized incidence ranging from ~2 to ~20 cases per 10,000 wearers, and sometimes resulting in permanent vision loss. Research suggests that the pathogenesis of contact lens-associated microbial keratitis is complex and multifactorial, likely requiring multiple conspiring factors that compromise the intrinsic resistance of a healthy cornea to infection. Here, we outline our perspective of the mechanisms by which contact lens wear sometimes renders the cornea susceptible to infection, focusing primarily on our own research efforts during the past three decades. This has included studies of host factors underlying the constitutive barrier function of the healthy cornea, its response to bacterial challenge when intrinsic resistance is not compromised, pathogen virulence mechanisms, and the effects of contact lens wear that alter the outcome of host-microbe interactions. For almost all of this work, we have utilized the bacterium Pseudomonas aeruginosa because it is the leading cause of lens-related microbial keratitis. While not yet common among corneal isolates, clinical isolates of P. aeruginosa have emerged that are resistant to virtually all currently available antibiotics, leading the United States CDC (Centers for Disease Control) to add P. aeruginosa to its list of most serious threats. Compounding this concern, the development of advanced contact lenses for biosensing and augmented reality, together with the escalating incidence of myopia, could portent an epidemic of vision-threatening corneal infections in the future. Thankfully, technological advances in genomics, proteomics, metabolomics and imaging combined with emerging models of contact lens-associated P. aeruginosa infection hold promise for solving the problem - and possibly life-threatening infections impacting other tissues.     

Acrylamide exposure impairs blood-cerebrospinal fluid barrier function

Previous studies show that chronic acrylamide exposure leads to central and peripheral neu- ropathy. However, the underlying mechanisms remained unclear. In this study, we examined the permeability of the blood-cerebrospinal fluid barrier, and its ability to secrete transthyretin and transport leptin of rats exposed to acrylamide for 7, 14, 21 or 28 days. Transthyretin levels in cerebrospinal fluid began to decline on day 7 after acrylamide exposure. The sodium fluorescein level in cerebrospinal fluid was increased on day 14 after exposure. Evans blue concentration in cerebrospinal fluid was increased and the cerebrospinal fluid/serum leptin ratio was decreased on days 21 and 28 after exposure. In comparison, the cerebrospinal fluid/serum albumin ratio was increased on day 28 after exposure. Our findings show that acrylamide exposure damages the blood-cerebrospinal fluid barrier and impairs secretory and transport functions. These changes may underlie acrylamide-induced neurotoxicity.     

腹腔镜胃癌根治术对肠道屏障功能损伤的研究分析

目的:对比腹腔镜与传统开腹胃癌根治术对胃癌患者肠道屏障功能的损伤及手术效果,为临床术式选择提供依据。方法:选择2008年10月至2012年10月113例胃癌患者,其中57例为观察组,行腹腔镜胃癌D2根治术;56例为对照组,行开腹胃癌D2根治术。观察两组患者手术时间、失血量、切口长度、肠道功能恢复时间、清除淋巴结数量、住院时间及术后第1天、第3天、第5天、第7天血浆D-乳酸浓度、血浆二胺氧化酶浓度、C-反应蛋白值等。结果:两组淋巴结清除数量差异无统计学意义(P>0.05);手术时间观察组长于对照组,但在出血量、切口长度、肠道功能恢复时间及住院时间方面观察组明显优于对照组,差异有统计学意义(P<0.01)。两组患者术后第1天、第3天血浆D-乳酸浓度、二胺氧化酶浓度及C-反应蛋白值差异有统计学意义(P<0.05);术后第5天、第7天血浆D-乳酸浓度、二胺氧化酶浓度及C-反应蛋白值差异有统计学意义(P<0.01)。结论:腹腔镜胃癌根治术是安全、有效的微创手术,与传统开腹胃癌根治术相比,对肠道屏障功能的损伤更小,更利于患者术后快速恢复,值得临床推广。     

Primary Malignant Melanoma of Maxillary Gingiva

Malignant melanoma of maxillary gingiva is a rare clinical entity. Mucosal melanoma is more aggressive than cutaneous form and carries comparatively poorer prognosis. High index of suspicion is required for diagnosing malignant melanoma of oral cavity. Any pigmented lesion in the oral cavity should be taken seriously by the clinician.