N-Acetylcysteine reverses silver nanoparticle intoxication in rats

The increasing use of silver nanoparticles (AgNPs) in consumer products raises the risk of human toxicity. Currently, there are no therapeutic options or established treatment protocols in cases of AgNPs intoxication. We demonstrated previously that thiol antioxidants compounds can reverse the cytotoxicity induced by AgNPs in Huh-7 hepatocarcinoma cells. Here, we investigated the use of N-acetylcysteine (NAC) against the systemic toxic effects of AgNPs (79.3?nm) in rats. Biochemical, histopathological, hematological, and oxidative parameters showed that a single intravenous injection of AgNPs (5?mg/kg b.w.) induced deleterious effects such as hepatotoxicity, potentially as a result of AgNPs accumulation in the liver. Treatment with a single intraperitoneal injection of NAC (1?g/kg b.w.) one hour after AgNPs exposure significantly attenuated all toxic effects evaluated and altered the bioaccumulation and release patterns of AgNPs in rats. The findings show that NAC may be a promising candidate for clinical management of AgNPs intoxication.     

Effect of Core Diameter and Surface Treatment on the Retention of Resin Composite Cores to Prefabricated Endodontic Posts

PURPOSE: With advances in adhesive dentistry and current emphasis on esthetic restorations, dowel systems have been developed to take advantage of these new techniques. Of interest when using these systems is the interaction between core materials and post materials. This investigation compared the tensile retentive force of two resin composite core materials to two metallic and one non-metallic prefabricated endodontic posts. Two dimensions of core build-up and two post-surface treatments were tested. MATERIALS AND METHODS: One hundred twenty posts (stainless steel, titanium alloy, and glass fiber-impregnated resin) were secured in a jig with 4 mm of the post extending into a cylindrical matrix. The matrix formed cylinders with diameters of 3 and 5 mm into which resin composite was inserted. The posts were treated or not treated with a bonding agent. After storage for 24 hours at 100% humidity, five specimens per condition were tested in an Instron testing machine at a crosshead speed of 0.5 mm/min. Failure loads were recorded in kilograms and failure modes were observed under light microscopy (40 x). Four-way analysis of variance and multiple comparison testing were used to compare means at the 0.05 level of significance. RESULTS: The means and standard deviations of tensile loads were calculated. All variables were significant in either main effects or interactions ( p<0.05). Fisher's PLSD intervals for post, core, treatment, and diameter were 2.0, 1.6, 1.6, and 1.6 kg, respectively. In most cases, the retentive force recorded for metallic posts was higher than that of glass fiber posts. Titanium posts had higher retentive forces than did the stainless steel posts. For metallic posts, 5-mm cores provided higher forces than 3-mm cores. In the glass fiber group, core diameter was not significant. For core materials, Build-It gave higher results with stainless steel posts, and FluoroCore gave higher results with the titanium ones. The surface treatment results were mixed. In the metallic post groups the adhesive failure data ranged between 80% and 100%, whereas in the glass fiber post groups, adhesive failures ranged between 60% and 70%. CONCLUSIONS: Within the limitations of this study, the metallic post groups always provided higher tensile retentive forces, with the titanium post groups showing higher retentive forces than the stainless steel ones. In the glass fiber post groups, different core diameters did not affect retention values.     

Effect of a portal venous stent for gastrointestinal hemorrhage from jejunal varices caused by portal hypertension after pancreatoduodenectomy

We report herein the case of a 64-year-old man successfully treated by portal venous stent placement for repeated gastrointestinal bleeding associated with jejunal varices. He was admitted to our hospital with melena 8 years after having a pancreatoduodenectomy for carcinoma of the papilla of Vater. From portogram findings showing severe portal vein (PV) stenosis and dilated collaterals through the jejunal vein of the Roux-en-Y loop, jejunal varices resulting from PV stenosis were suspected as the cause of the melena. A metallic stent was placed in the PV following percutaneous transhepatic PV angioplasty. Although the cure of hemorrhagic jejunal varices caused by PV stenosis is difficult in patients who have undergone major abdominal surgery, patency of the stent in this patient has been maintained for 32 months without gastrointestinal hemorrhage. Metallic stent placement is recommended as a useful treatment for PV stenosis that is less invasive than open surgery.     

金属胆道支架治疗恶性梗阻性黄疸的临床疗效

目的 探讨胆道金属支架治疗恶性阻塞性黄疸(MOJ)的临床疗效. 方法 回顾性分析1998年2月至2009年2月的241例MOJ患者临床资料,所有患者均接受经皮肝穿刺胆道金属支架置入术.评价预后以死亡为研究终点,随访时间截至2010年2月,统计学分析比较患者生存期及治疗前后各实验室指标改变,评价疗效.计数资料采用x2检验,计量资料用t检验;生存率比较采用Kaplan-Meier法;Cox回归模型评估各危险因素对生存时间的影响. 结果 支架置入技术成功率为100％.支架置入术后4周内血清胆红素下降明显(P＜ 0.05),术后院内死亡11例,失访28例,202例获得完整随访资料;随访时间为8～ 193周,其13周、26周、39周、52周的生存率分别为87％、66％、56％、41％,中位生存期为43.55周.同期支架通畅率分别为70％、46％、36％和24％,平均通畅时间为27.57周.Cox回归分析示:术前胆红素＜ 221 μmol/L(P=0.01)及术后胆红素下降比例超过50％(P=0.002)者预后较好.结论 胆道金属支架置入术治疗MOJ技术安全、可行,可有效缓解黄疸症状,延长生存期.高胆红素血症及胆红素下降程度低于50％是影响MOJ患者生存率的因素.     

Clinical outcomes of palliative self-expanding metallic stents in patients with malignant colorectal obstruction

OBJECTIVE: Self‐expanding metallic stents (SEMS) are useful palliative option and a bridge to surgery in malignant colorectal obstruction. The aim of this study was to evaluate the clinical outcomes of SEMS to palliate colorectal malignant obstruction. METHODS: Malignant colorectal obstructive patients who underwent SEMS insertion at the National Cancer Center, Korea from January 2004 to June 2008 were enrolled in the study. Patients' clinical characteristics, outcomes and complications for palliative SEMS insertion were retrospectively analyzed. RESULTS: A total of 54 patients were enrolled in the palliative SEMS group and 48 patients with obstructive CRC were included in the SEMS as the bridge to surgery group. Obstruction of the left colon occurred in 52 patients of the palliative SEMS group and all patients in SEMS as bridge to surgery group. For primary SEMS insertion, the technical success (TS) rate was 87.0% and the clinical success (CS) rate 89.4%, while the rates of early and late complications were 24.1% and 23.4%, respectively. There was no procedure‐related mortality. Stent migration rate was higher in the cases treated with small diameter and covered type of stents. Median time to reobstruction and migration were 85 and 101 days, respectively. TS and CS rates for SEMS reinsertion were comparable to those for primary SEMS insertion. CONCLUSIONS: Palliative SEMS are effective and favorable procedures for malignant colorectal obstruction but with some complications. Stent migration is associated with covered type and small diameter stents while other factors including length of stent and chemotherapy do not affect stent complications in the present study.     

超声对恶性肝门部胆管梗阻应用经皮经肝自膨式金属内支架疗效的评价

目的：评价超声对恶性肝门部胆管梗阻（MHBO）应用经皮肝自膨式金属内支架（EMBE）的疗效。方法：对30例恶性肝门部胆管梗阻患者在超声引导下采用经皮经肝自膨式金属内支架。结果：在超声引导下采用（EMBE），可避开肝内血管，且不受扩张胆管内径大小及走行方向的影响，一次性成功率高，负损伤小。结论：用超声监测肝内胆管径可观察胆管开通状况，作为衡量减黄效果的重要指标。EMBE早期合并症少，术后生存期长，如加用放射疗法，可大大提高生存期。     

Enhancement of Magnetic and Tensile Mechanical Performances in Fe-Based Metallic Microwires Induced by Trace Ni-Doping

Herein, the effect of Ni-doping amount on microstructure, magnetic and mechanical properties of Fe-based metallic microwires was systematically investigated further to reveal the influence mechanism of Ni-doping on the microstructure and properties of metallic microwires. Experimental results indicate that the rotated-dipping Fe-based microwires structure is an amorphous and nanocrystalline biphasic structure; the wire surface is smooth, uniform and continuous, without obvious macro- and micro-defects that have favorable thermal stability; and moreover, the degree of wire structure order increases with an increase in Ni-doping amount. Meanwhile, FeSiBNi2 microwires possess the better softly magnetic properties than the other wires with different Ni-doping, and their main magnetic performance indexes of M_s, M_r, H_c and μ_m are 174.06 emu/g, 10.82 emu/g, 33.08 Oe and 0.43, respectively. Appropriate Ni-doping amount can effectively improve the tensile strength of Fe-based microwires, and the tensile strength of FeSiBNi3 microwires is the largest of all, reaching 2518 MPa. Weibull statistical analysis also indicates that the fracture reliability of FeSiBNi2 microwires is much better and its fracture threshold value σ_u is 1488 MPa. However, Fe-based microwires on macroscopic exhibit the brittle fracture feature, and the angle of sideview fracture θ decreases as Ni-doping amount increases, which also reveals the certain plasticity due to a certain amount of nanocrystalline in the microwires structure, also including a huge amount of shear bands in the sideview fracture and a few molten drops in the cross-section fracture. Therefore, Ni-doped Fe-based metallic microwires can be used as the functional integrated materials in practical engineering application as for their unique magnetic and mechanical performances.     

Contact dermatitis from metallic palladium in patients reacting to palladium chloride

1307 consecutive patients were patch tested with PdCl2 1% pet. 32 patients were positive; 29 also showed a reaction to NiSO4. 470 patients were additionally tested with a metallic palladium disc. 3 had a positive reaction, and none of them reacted to PdCl2 or NiSO4 pet. A positive patch test to PdCl2 pet. is in most cases probably due to a cross-reaction with nickel in nickel-sensitive subjects. Patients positive to PdCl2 tolerate skin contact with metallic palladium.     

Contact dermatitis in children: 6 years experience (1992–1997)

We report the results of patch tests carried out over the last 6 years (1992-1997) on 141 children. This corresponds to 2.8% of the total patients who were patch tested in our Allergy Department (5,014). These 141 children were patch tested using the TRUE Test^TM standard series and an additional allergen, metallic mercury. Allergens from the Chemotechnique medicaments, cosmetics, plants and shoe series were added in some. The most frequent localization of eczema was to the feet, face and hands and the most frequent suspected causes were costume jewellery, footwear, topical medicaments and cosmetics. The most frequent allergens, assessed by degree of relevance, were first, nickel, followed by cobalt, mercurials (thimerosal and metallic mercury), fragrance and rubber chemicals (naphthyl mix, mercapto mix, carba mix and PPD mix). 13 children, 18% of the total, between the ages of 12 and 14 years, showed positivities relevant to some occupation, i.e., metalworking, building, hairdressing, catering, etc. Once patch tests had been carried out and relevant positive patch tests assessed, the most frequent diagnoses were contact dermatitis 45%, atopic dermatitis 25%, juvenile plantar dermatitis 15%, and other diagnoses in the remaining 15%.