G-CSF对大鼠烧伤合并海水浸泡后内皮祖细胞的影响

目的观察早期应用粒细胞集落刺激因子（G-CSF）对大鼠烧伤合并海水浸泡后血液中的内皮祖细胞（endothe-lial progenitor cells,EPC）的影响。方法将26只SD大鼠随机分成3组：对照组、烧伤合并海水浸泡模型组和烧伤合并海水浸泡＋G-CSF实验组。在模型制备后的30 min、2 h、6 h和24 h,使用双色荧光标记流式细胞术检测不同组别大鼠的血中EPC数量。结果烧伤合并海水浸泡使血中EPC的数量显著降低,G-CSF可以部分逆转烧伤合并海水浸泡对EPC数量减少的作用。结论在烧伤合并海水浸泡情况下,使用G-CSF可增加血中EPC数量,并可能增强创面的修复能力。     

Dissolution and bandgap paradigms for predicting the toxicity of metal oxide nanoparticles in the marine environment: an in vivo study with oyster embryos

Dissolution and bandgap paradigms have been proposed for predicting the ability of metal oxide nanoparticles (NPs) to induce oxidative stress in different in vitro and in vivo models. Here, we addressed the effectiveness of these paradigms in vivo and under conditions typical of the marine environment, a final sink for many NPs released through aquatic systems. We used ZnO and MnO₂ NPs as models for dissolution and bandgap paradigms, respectively, and CeO₂ NPs to assess reactive oxygen radical (ROS) production via Fenton-like reactions in vivo. Oyster embryos were exposed to 0.5–500?μM of each test NP over 24?h and oxidative stress was determined as a primary toxicity pathway across successive levels of biological complexity, with arrested development as the main pathological outcome. NPs were actively ingested by oyster larvae and entered cells. Dissolution was a viable paradigm for predicting the toxicity of NPs in the marine environment, whereas the surface reactivity based paradigms (i.e. bandgap and ROS generation via Fenton-like reaction) were not supported under seawater conditions. Bio-imaging identified potential cellular storage-disposal sites of solid particles that could ameliorate the toxicological behavior of non-dissolving NPs, whilst abiotic screening of surface reactivity suggested that the adsorption-complexation of surface active sites by seawater ions could provide a valuable hypothesis to explain the quenching of the intrinsic oxidation potential of MnO₂ NPs in seawater.     

早期应用头孢菌素类抗生素对腹腔海水浸泡伤大鼠的救治研究

目的　观察早期应用头孢菌素类抗生素对腹腔海水浸泡伤大鼠的救治效果。方法　选取SD大鼠 6 0只 ,随机均分为腹腔海水浸泡组 (A组 ,n =30 )及腹腔海水浸泡后治疗组 (B组 ,n =30 ) ,观察每组术后血浆内毒素 (endotoxin ,ET)、肿瘤坏死因子 (tumornecrosisfactor,TNF)、细菌培养水平变化。另外再选取SD大鼠 4 0只 ,随机均分为C组 (n =2 0 )及D组 (n =2 0 ) ,C组处理同A组 ,D组处理同B组 ,观察C、D两组在两种不同处理情况下实验动物的存活情况。结果　①腹腔海水浸泡后两组血浆ET、TNF水平均显著升高 (P <0 0 1) ,而术后 12h始B组水平开始显著低于A组 (P <0 0 5 ) ;②腹腔海水浸泡后 2 4hB组细菌培养总阳性率 (2 /12 )显著低于A组 (8/12 ) (P <0 0 5 ) ;③D组存活率 (9/2 0 )显著高于C组 (2 /2 0 ) (P <0 0 5 )。结论　腹腔海水浸泡后早期应用头孢菌素类抗生素减轻了机体感染和继发损伤的程度 ,有利于提高创伤后动物存活率。     

The body recovered from water: considerations for an approach to the non-suspicious post-mortem examination

Bodies from the water are not commonly encountered in everyday practice, either by the forensic pathologist or by the coroner's pathologist. The body recovered from water can pose particular difficulty to the unsuspecting pathologist, especially if there is evidence of decomposition or if the body is injured. However, it is important to have an understanding for the necessity of the post-mortem examination and to identify those findings which may support drowning or immersion, in the absence of other relevant findings. Limited autopsy has no place in the pathological examination of a body recovered from water as arriving at a conclusion of drowning relies on excluding all other causes. Currently, it is recognized that non-invasive autopsy is not ideal in diagnosing death in cases recovered from water and therefore conventional invasive post-mortem examination with histology and toxicology remains paramount.     

Effects of electrode gap and electric potential on chlorine generation of electrolyzed deep ocean water

Electrolyzed water is a sustainable disinfectant, which can comply with food safety regulations and is environmentally friendly. A two-factor central composite design was adopted for studying the effects of electrode gap and electric potential on chlorine generation efficiency of electrolyzed deep ocean water. Deep ocean water was electrolyzed in a glass electrolyzing cell equipped with platinum-plated titanium anode and cathode. Results showed high electric efficiency at a low cell potential, and a high current density and high chlorine concentration at a high cell potential and low electrode gap. Current efficiency of the system was not significantly affected by electrode gap and electric potential. A small electrode gap reduced the required cell potential and resulted in high energy efficiency. The optimal choice of electrode gap and cell potential depends on the chlorine level of the electrolyzed deep ocean water to be produced, and a small electrode gap is preferred.     

Stimulation of bone growth following zinc incorporation into biomaterials

Rapid development of zinc biology has broadened the applications of Zn-incorporated biomaterials to tissue engineering but also raised concerns about the long-term safety of released Zn²⁺ ions. Clinical success hinges on the amount of incorporated zinc and subsequent optimized release sufficient to stimulate osseointegration. In this study, zinc is incorporated into the sub-surface of TiO₂ coatings by plasma immersion ion implantation and deposition (PIII&D). The Zn-implanted coatings show significant improvement compared to the “bulk-doped” coatings prepared by plasma electrolyte oxidation in terms of osteogenesis in vitro and in vivo. Molecular and cellular osteogenic activities demonstrate that rBMSCs cultured on the Zn-implanted coatings have higher ALP activity and up-regulated osteogenic-related genes (OCN, Col-I, ALP, Runx2) compared to the bulk-doped Zn coatings and controls. In vivo osseointegration studies conducted for 12 weeks on the rat model show early-stage new bone formation and the bone contact ratio (12 week) on the Zn-implanted coating is larger. The ZnT1 and ZIP1 gene expression studies demonstrate that the Zn-implanted coatings can better stimulate bone growth with reduced Zn release than those doped with zinc throughout the coatings.     

常用消毒方法灭活藻酸盐印模表面乙肝病毒的效果

目的:观察几种常用消毒方法灭活藻酸盐印模表面乙肝病毒的效果.方法:采用ADA建议的消毒方法,对表面污染有乙肝病毒血清的藻酸盐印模进行消毒实验,采用酶联免疫分析法(Elisa)对乙肝病毒表面抗原灭活效果进行检测.结果:1500mg/L的NaClO消毒液浸泡消毒10min或喷涂消毒25min可完全灭活HBsAg;2%中性强化戊二醛消毒液浸泡消毒40min可完全灭活HBsAg;2%中性强化戊二醛消毒液喷涂消毒60min灭活HBsAg效果不可靠;臭氧消毒60min仍无效.结论:浓度为1500mg/L的NaClO消毒液浸泡消毒10min或喷涂消毒25min、2%中性强化戊二醛消毒液浸泡消毒40 min三种消毒方法可灭活印模表面的乙肝病毒.     

Compliance of Resilient Denture Liners Immersed in Effervescent Denture Cleansers

PURPOSE: Six resilient denture liners (RDL) were exposed to two immersion effervescent denture cleansers to evaluate change in compliance over a simulated 1 year time interval. MATERIALS AND METHODS: Ten samples of each material, Molloplast B, Mollosil, MPDS-SL, Permasoft, Softline, and Sofreliner were exposed to either Fixodent or Efferdent denture cleanser. A cyclic load was applied in a squarewave fashion to derive a load displacement curve to measure compliance at 0, 7, 30, 180, and 360 simulated days. RESULTS: All 12 of the material/cleanser combinations demonstrated a significant change in compliance at each time interval relative to baseline. Mollosil had the greatest increase in flexibility from baseline, and MPDS-SL had the smallest increase in flexibility. In general, chairside materials demonstrated greater change in compliance from baseline compared to laboratory materials. Materials subjected to Fixodent cleanser, when averaged over time, were significantly more flexible than materials exposed to Efferdent cleanser. CONCLUSIONS: Exposure of resilient soft liners to two common cleansers resulted in a significant increase in flexibility. This change in flexibility depended slightly, though significantly, on the type of cleanser, and appeared to be more significant with time. In general, chairside materials seemed to change more than laboratory-processed liners. The exception was Permasoft that was fabricated as a laboratory material but behaved like a chairside material. CLINICAL SIGNIFICANCE: The initiator of the polymerization reaction rather than the mode of polymerization may be more important in predicting a change in the flexibility of RDLs. Constituents within the oral environment may be more responsible for changes in RDL flexibility than denture cleansers.