不同连接方式种植体对周围组织影响的临床比较

目的比较平台转换种植体和传统基台连接种植体对上颌美学区单牙种植周围组织的影响。方法随机选择95例（110枚）上颌美学区单牙种植修复患者,其中Ankylos系统（平台转换）47例（54枚种植体）,Nobel Replace系统（传统基台连接）48例（56枚种植体）。在患者最终修复后36～62个月进行随访,拍摄X线片及临床检查来记录种植体周围骨组织和牙龈组织的状况,比较两组种植体边缘骨吸收量和周围软组织红色美学指数。利用统计学方法分析所得数据。结果不同连接方式种植修复后种植体周围边缘骨吸收量与红色美学指数具有显著差异,平台转换种植体的骨吸收量明显少于传统基台连接组,红色美学指数也高于传统基台连接。结论平台转换种植体在上颌美学区单牙种植修复相较于传统基台连接种植体能更有效的保留周围骨组织且美学效果较佳。     

The effects of micro-implant assisted rapid palatal expansion (MARPE) on the nasomaxillary complex—a finite element method (FEM) analysis

Background

Orthodontic palatal expansion appliances have been widely used with satisfactory and, most often, predictable clinical results. Recently, clinicians have successfully utilized micro-implants with palatal expander designs to work as anchors to the palate to achieve more efficient skeletal expansion and to decrease undesired dental effects. The purpose of the study was to use finite element method (FEM) to determine the stress distribution and displacement within the craniofacial complex when simulated conventional and micro-implant-assisted rapid palatal expansion (MARPE) expansion forces are applied to the maxilla. The simulated stress distribution produced within the palate and maxillary buttresses in addition to the displacement and rotation of the maxilla could then be analyzed to determine if micro-implants aid in skeletal expansion.

Methods

A three-dimensional (3D) mesh model of the cranium with associated maxillary sutures was developed using computed tomography (CT) images and Mimics modeling software. To compare transverse expansion stresses in rapid palatal expansion (RPE) and MARPE, expansion forces were distributed to differing points on the maxilla and evaluated with ANSYS simulation software.

Results

The stresses distributed from forces applied to the maxillary teeth are distributed mainly along the trajectories of the three maxillary buttresses. In comparison, the MARPE showed tension and compression directed to the palate, while showing less rotation, and tipping of the maxillary complex. In addition, the conventional hyrax displayed a rotation of the maxilla around the teeth as opposed to the midpalatal suture of the MARPE. This data suggests that the MARPE causes the maxilla to bend laterally, while preventing unwanted rotation of the complex.

Conclusions

In conclusion, the MARPE may be beneficial for hyperdivergent patients, or those that have already experienced closure of the midpalatal suture, who require palatal expansion and would worsen from buccal tipping of the teeth or maxillary complex.     

国人髌骨解剖标志点在髌骨置换截骨中意义

目的:全膝置换中进行正确的髌骨截骨是减少置换后髌骨并发症的重要因素,实验利用正常国人髌骨解剖标志点,探讨其在国人髌骨置换髌骨截骨中的意义.方法:实验于2006-06/2007-01在上海长征医院关节外科完成.①实验材料:成人尸体50膝(由解放军第二军医大学提供).②实验过程:采用标准的膝关节正中皮肤切口入路打开关节腔,外翻髌骨,测量髌骨厚度,暴露髌腱外缘髌骨止点及股四头肌内、外缘的髌骨止点,美兰标记,由同一位医师利用摆锯截骨.③评估:测量截骨前髌骨厚度及截骨后残存髌骨厚度.结果:髌骨截骨前平均厚度为(23.39±1.19)mm,残存髌骨的平均厚度为(13.83±1.04)mm,大于12 mm的要求(文献报道的国人髌骨截骨术后残余厚度应大于12 mm,P＜0.05).结论:利用髌腱外缘及股四头肌内、外缘作为截骨的解剖标志点进行国人的髌骨截骨,残余髌骨厚度满足髌骨假体置换的要求,是适合国人解剖特点的髌骨截骨标志点.     

Development of an Attenuated Tat Protein as a Highly-effective Agent to Specifically Activate HIV-1 Latency

Although combined antiretroviral therapy (cART) successfully decreases plasma viremia to undetectable levels, the complete eradication of human immunodeficiency virus type 1 (HIV-1) remains impractical because of the existence of a viral reservoir, mainly in resting memory CD4⁺ T cells. Various cytokines, protein kinase C activators, and histone deacetylase inhibitors (HDACi) have been used as latency-reversing agents (LRAs), but their unacceptable side effects or low efficiencies limit their clinical use. Here, by a mutation accumulation strategy, we generated an attenuated HIV-1 Tat protein named Tat-R5M4, which has significantly reduced cytotoxicity and immunogenicity, yet retaining potent transactivation and membrane-penetration activity. Combined with HDACi, Tat-R5M4 activates highly genetically diverse and replication-competent viruses from resting CD4⁺ T lymphocytes isolated from HIV-1-infected individuals receiving suppressive cART. Thus, Tat-R5M4 has promising potential as a safe, efficient, and specific LRA in HIV-1 treatment.     

Osteoclasts are dispensable for hematopoietic stem cell maintenance and mobilization

Hematopoietic stem cells (HSCs) are maintained in a specific bone marrow (BM) niche in cavities formed by osteoclasts. Osteoclast-deficient mice are osteopetrotic and exhibit closed BM cavities. Osteoclast activity is inversely correlated with hematopoietic activity; however, how osteoclasts and the BM cavity potentially regulate hematopoiesis is not well understood. To investigate this question, we evaluated hematopoietic activity in three osteopetrotic mouse models: op/op, c-Fos-deficient, and RANKL (receptor activator of nuclear factor kappa B ligand)-deficient mice. We show that, although osteoclasts and, by consequence, BM cavities are absent in these animals, hematopoietic stem and progenitor cell (HSPC) mobilization after granulocyte colony-stimulating factor injection was comparable or even higher in all three lines compared with wild-type mice. In contrast, osteoprotegerin-deficient mice, which have increased numbers of osteoclasts, showed reduced HSPC mobilization. BM-deficient patients and mice reportedly maintain hematopoiesis in extramedullary spaces, such as spleen; however, splenectomized op/op mice did not show reduced HSPC mobilization. Interestingly, we detected an HSC population in osteopetrotic bone of op/op mice, and pharmacological ablation of osteoclasts in wild-type mice did not inhibit, and even increased, HSPC mobilization. These results suggest that osteoclasts are dispensable for HSC mobilization and may function as negative regulators in the hematopoietic system.     

Impact of timing of renal replacement therapy initiation on outcome of septic acute kidney injury

Introduction

Sepsis is the leading cause of acute kidney injury (AKI) in critical patients. The optimal timing of initiating renal replacement therapy (RRT) in septic AKI patients remains controversial. The objective of this study is to determine the impact of early or late initiation of RRT, as defined using the simplified RIFLE (risk, injury, failure, loss of kidney function, and end-stage renal failure) classification (sRIFLE), on hospital mortality among septic AKI patients.

Methods

Patient with sepsis and AKI requiring RRT in surgical intensive care units were enrolled between January 2002 and October 2009. The patients were divided into early (sRIFLE-0 or -Risk) or late (sRIFLE-Injury or -Failure) initiation of RRT by sRIFLE criteria. Cox proportional hazard ratios for in hospital mortality were determined to assess the impact of timing of RRT.

Results

Among the 370 patients, 192 (51.9%) underwent early RRT and 259 (70.0%) died during hospitalization. The mortality rate in early and late RRT groups were 70.8% and 69.7% respectively (P > 0.05). Early dialysis did not relate to hospital mortality by Cox proportional hazard model (P > 0.05). Patients with heart failure, male gender, higher admission creatinine, and operation were more likely to be in the late RRT group. Cox proportional hazard model, after adjustment with propensity score including all patients based on the probability of late RRT, showed early dialysis was not related to hospital mortality. Further model matched patients by 1:1 fashion according to each patient's propensity to late RRT showed no differences in hospital mortality according to head-to-head comparison of demographic data (P > 0.05).

Conclusions

Use of sRIFLE classification as a marker poorly predicted the benefits of early or late RRT in the context of septic AKI. In the future, more physiologically meaningful markers with which to determine the optimal timing of RRT initiation should be identified.     

骨髓增生异常综合征患者骨髓异常克隆细胞起源的初步研究

本研究旨在探讨骨髓增生异常综合征(MDS)患者骨髓异常克隆细胞的起源,即MDS患者骨髓CD34+CD38-造血干细胞和CD34+CD38+祖细胞中是否存在恶性克隆细胞及其比例。用免疫磁珠分选技术(MACS)分选9例染色体异常的MDS患者(8三体4例,含有8三体的复杂核型1例,5q-2例,含有5q-的复杂核型1例,5q-合并8三体1例)的骨髓单个核细胞(BMMNC)中的CD34+CD38-细胞和CD34+CD38+细胞,分别涂片;然后在上述涂片上通过荧光原位杂交(FISH)方法比较CD34+CD38-和CD34+CD38+两群细胞中异常克隆细胞的百分比。结果发现,这两群细胞均有异常克隆累及,但CD34+CD38-干细胞中异常克隆的比例(41.8±8.4)%低于CD34+CD38+祖细胞(72.4±7.7)%(p<0.001),而在有核细胞检测的异常克隆细胞比例为(70.8±9.2)%。结论:提示MDS患者中5q-和+8异常克隆均可能起源于造血干细胞阶段,而在祖细胞阶段异常克隆占优势。     

Identification of nafamostat mesylate as a selective stimulator of NK cell IFN-γ production via metabolism-related compound library screening

Natural killer (NK) cells play important roles in controlling virus-infected and malignant cells. The identification of new molecules that can activate NK cells may effectively improve the antiviral and antitumour activities of these cells. In this study, by using a commercially available metabolism-related compound library, we initially screened the capacity of compounds to activate NK cells by determining the ratio of interferon-gamma (IFN-γ)⁺ NK cells by flow cytometry after the incubation of peripheral blood mononuclear cells (PBMCs) with IL-12 or IL-15 for 18 h. Our data showed that eight compounds (nafamostat mesylate (NM), loganin, fluvastatin sodium, atorvastatin calcium, lovastatin, simvastatin, rosuvastatin calcium, and pitavastatin calcium) and three compounds (NM, elesclomol, and simvastatin) increased the proportions of NK cells and CD3⁺ T cells that expressed IFN-γ among PBMCs cultured with IL-12 and IL-15, respectively. When incubated with enriched NK cells (purity?≥?80.0%), only NM enhanced NK cell IFN-γ production in the presence of IL-12 or IL-15. When incubated with purified NK cells (purity?≥?99.0%), NM promoted NK cell IFN-γ secretion in the presence or absence of IL-18. However, NM showed no effect on NK cell cytotoxicity. Collectively, our study identifies NM as a selective stimulator of IFN-γ production by NK cells, providing a new strategy for the prevention and treatment of infection or cancer in select populations.

     

经输尿管硬镜钬激光碎石术与气压弹道碎石术治疗输尿管多发结石的临床研究

目的比较钬激光碎石术与气压弹道碎石术治疗单侧输尿管多发结石的临床效果和安全性。方法选择2008年11月-2014年12月该院收治的单侧输尿管多发结石患者45例,随机分为两组,钬激光组23例,气压弹道组22例。钬激光组采用输尿管镜下钬激光碎石术治疗,气压弹道组采用气压弹道碎石术治疗,比较两组患者的治疗效果和临床安全性。结果钬激光组手术时间为(57.6±9.3)min,住院时间为(2.3±1.1)d;气压弹道组手术时间为(68.0±11.7)min,住院时间为(3.6±1.5)d,两组比较差异有统计学意义(P0.05)。两组的碎石成功率、碎石总有效率均为100.00%。两组的结石排净率、术后并发症发生率差异无统计学意义(P0.05)。结论钬激光与气压弹道均可用于治疗单侧输尿管多发结石,钬激光碎石术更具有优势,值得临床推广应用。