Assessment of dental implant surface stability at the nanoscale level

ObjectivesTo study the oxide layer stability of certified dental implants of system "P", made based on TiO₂ alloy with carbon coating. To perform a comparative statistical analysis of the obtained data with the available data for the dental implants of systems "A" and "B".MethodsX-ray microtomography and X-ray fluorescence analysis were used to study soft tissue biopsy specimens. Supernatants were studied by dynamic light scattering and transmission electron microscopy when simulating free emission of nanoscale metal oxide particles from the surface of dental implants as well as when simulating physical loading. A comparative analysis of three parameters of nanoscale particles was performed by statistical data analysis. The surface of the "P" system dental implant with surface treatment was analyzed by scanning electron microscopy.ResultsBoth free emission of nanoscale oxide layer particles and yield of nano- and microscale particles during simulation of physical load were confirmed. Statistically significant differences were noted in a comparative analysis of the size and frequency of occurrence of these particles in the supernatants obtained from the surfaces of three dental implant systems. The elemental composition of the particles and the composition and structure of the "P" system dental implants themselves were analyzed.SignificanceThe developed method of dynamic light scattering can be used to compare the stability of the oxide layer of standardized medical products manufactured on the basis of the TiO₂ alloy.     

利用电子顺磁波谱技术研究红参对羟自由基的清除作用

目的 探索电子顺磁波谱（electron paramagnetic resonance，EPR）技术检测红参清除自由基活性的适合产生体系，并研究红参对羟自由基（?OH）的清除作用及其物质基础。方法 采用电子顺磁共振波谱仪检测不同浓度的红参提取液对?OH的体外清除作用，并用液质联用技术（LC-MS）分析红参中的主要皂苷成分，然后研究这些人参皂苷成分对?OH的清除作用。结果 确定了羟自由基的生成体系为：Fe²⁺ 0.1 mmol?L^-1、H₂O₂ 500 mmol?L^-1、DMPO 225 mmol?L^-1；不同浓度的红参提取液对?OH具有明显的清除作用，且其清除?OH的效力与浓度成正相关；LC-MS分析显示该红参提取液中主要含有Rh1、Rf、Rb3、F1、F2、Rg3、Rg5等成分，其中人参皂苷Rg5的清除自由基活性最强。结论 本研究建立了用EPR技术研究红参清除自由基活性的适合产生体系，红参具有明显的清除?OH的能力，且人参皂苷Rg5是其清除自由基的活性成分之一，确定了红参抗自由基的主要物质基础，为红参及人参皂苷Rg5的开发、应用提供了科学依据和理论基础。     

神经内镜与显微镜下经鼻蝶入路手术切除无功能性垂体腺瘤疗效和安全性的Meta分析

目的 系统评价神经内镜与显微镜下经鼻蝶入路手术切除无功能性垂体腺瘤的疗效和安全性。方法 计算机检索PubMed 、Embase、Cochrane Center、中国生物医学文献数据库、维普中文科技期刊全文数据库、万方数据库、中国知网等中英文数据库有关神经内镜、显微镜下经鼻蝶入路无功能性垂体腺瘤切除术的文献，时限为2018年7月之前。指标包括肿瘤切除率、脑脊液渗漏发生率和视力恢复率。结果 共纳入19篇文献，2 383例。Meta分析结果:神经内镜手术全切除率比显微镜手术要高（75% vs 62%，P<0.001），神经内镜组视力恢复率也高于显微镜组（82% vs 59%，P<0.001）。两组脑脊液漏发生率无统计学差异（4%vs 6%，P=0.078）。结论 与显微镜下手术相比，神经内镜手术切除无功能性垂体腺瘤的疗效更好。     

Rapid diagnostic tests relying on antigen detection from stool as an efficient point of care testing strategy for giardiasis and cryptosporidiosis? Evaluation of a new immunochromatographic duplex assay

Microscopy is the gold standard for the diagnosis of gastrointestinal parasites but is time-consuming and dependent on operator skills. Rapid diagnostic tests represent alternative methods but most evaluations have been conducted on a limited number of samples preventing their implementation in the clinical setting. We evaluated a new CE-IVD marked immunochromatographic assay (Crypto/Giardia K-SeT®, Coris Bioconcept) for the detection of G. intestinalis and Cryptosporidium spp. in 2 phases (retrospective and prospective) on a set of 482 stool samples including rare Cryptosporidium species. Besides G. intestinalis, this test could represent a rapid and reliable alternative to the modified Ziehl-Neelsen staining for the diagnosis of cryptosporidiosis (sensitivity/specificity were 89.2%/99.3% and 86.7%/100% for G. intestinalis and Cryptosporidium resp.), reducing diagnostic delays. Such strategy would also be time-saving by avoiding wet mount microscopy and concentrations steps, being particularly appropriate for laboratories having little expertise in microscopy or not able to implement molecular diagnostic methods.     

Visualization of microneuromas by using in vivo confocal microscopy: An objective biomarker for the diagnosis of neuropathic corneal pain?

PurposeThe diagnosis of neuropathic corneal pain (NCP) is challenging, as it is often difficult to differentiate it from conventional dry eye disease (DED). In addition to eye pain, NCP can present with similar signs and symptoms of DED. The purpose of this study is to find an objective diagnostic sign to identify patients with NCP, using in vivo confocal microscopy (IVCM).MethodsThis was a comparative, retrospective, case-control study. Patients with clinical diagnosis of NCP (n = 25), DED (n = 30), and age- and sex-matched healthy controls (n = 16), who underwent corneal imaging with IVCM (HRT3/RCM) were included. Central corneal IVCM scans were analyzed by 2 masked observers for nerve density and number, presence of microneuromas (terminal enlargements of subbasal corneal nerve) and/or nerve beading (bead-like formation along the nerves), and dendritiform cell (DC) density.ResultsThere was a decrease in total nerve density in both NCP (14.14 ± 1.03 mm/mm²) and DED patients (12.86 ± 1.04 mm/mm²), as compared to normal controls (23.90 ± 0.92 mm/mm²; p < 0.001). However, total nerve density was not statistically different between NCP and DED patients (p = 0.63). Presence of nerve beading was not significantly different between patients and normal controls (p = 0.15). Interestingly, microneuromas were observed in all patients with NCP, while they were not present in any of the patients with conventional DED (sensitivity and specificity of 100%). DC density was significantly increased in both NCP (71.89 ± 16.91 cells/mm²) and DED patients (111.5 ± 23.86 cells/mm²), as compared to normal controls (24.81 ± 4.48 cells/mm² (p < 0.05). However, there was no significant difference in DC density between DED and NCP patients (p = 0.31).ConclusionIVCM may be used as an adjunct diagnostic tool for the diagnosis of NCP in the presence of neuropathic symptoms. Microneuromas may serve as a sensitive and specific biomarker for the diagnosis of NCP.     

文眉致白癜风七例

【摘要】 目的 报道文眉所致白癜风7例。方法 收集2017年12月至2019年5月河南省人民医院皮肤科诊治的7例文眉引起的白癜风，回顾其临床特点。结果 7例患者文眉后1个月至1年出现数根眉毛变白，早期均表现为眉毛变白，眉部皮肤正常，眉周逐渐出现白斑，边界不清。眉部皮损反射式共聚焦扫描显微镜特征：基底层及毛囊周围色素缺失，真皮浅、中层可见高折光无定形物（色料）。斑贴试验：文眉色料均为阴性，十二醇硫酸钠均呈阳性。结论 文眉后引起的白癜风，早期眉部皮肤未见色素减退斑，结合眉部皮损反射式共聚焦扫描显微镜特征可减少误诊。     

反射性共聚焦显微镜对早期蕈样肉芽肿定位诊断与疗效监测的研究

【摘要】 目的 分析早期蕈样肉芽肿（MF）皮损的反射性共聚焦显微镜（RCM）与组织病理学特征的一致性，探讨RCM作为病理学诊断早期MF的辅助价值及动态监测治疗反应的可行性。方法 2014年1月至2018年1月在杭州市第三人民医院皮肤科门诊收集临床疑诊MF病例40例，男26例，女14例，年龄（47.0 ± 17.6）岁。根据总结的早期MF的RCM特征，对活检部位进行初步定位后行组织病理学检查，对比MF的RCM与病理特征。对MF确诊病例进行窄谱中波紫外线联合干扰素治疗，运用RCM对靶向皮损跟踪随访，9个月后评价疗效。结果 在40例临床疑诊MF病例中，根据RCM特征初步诊断典型MF 8例，疑似MF18例，排除14例；根据MF病理学特征诊断典型MF12例，疑似14例，排除14例。一致性分析显示，RCM特征分类与病理诊断结果的Kappa系数为0.848，P < 0.01。RCM与组织病理学特征之间表皮低折光细胞浸润的相关性最高（Kappa系数 = 1，P = 0.005），其次是红斑期的真皮纤维化（Kappa系数 = 0.714，P = 0.035）。MF的RCM特征随着治疗的进行逐步恢复正常，但直至临床皮损完全缓解，非典型淋巴细胞依然存在。结论 RCM技术可用于早期疑诊MF皮损的病理取材定位，同时可尝试作为一种动态监测MF疗效的方法。     

Transmission and scanning electron microscopy of cutis rhomboidalis

Cutis rhomboidalis nuchae was assessed in a 65-year-old patient. Optical microscopy showed basophilic agglomerations in the reticular dermis with decreased elastic fibers. Transmission electron microscopy showed elongated, curved and fragmented structures, and in their interior the presence of electron-dense lumps was reduced and irregular, similar to modified elastic fibers, whereas the collagen fibers had a normal aspect. Scanning electron microscopy showed deposits between the bundles of collagen, resembling pebbles or stones. These findings demonstrate that, at one stage of the disease, the collagen remains normal and the alterations are seen in the elastic tissue.