表面活性剂对戊二醛消毒液稳定性的研究

目的：研究寻找一种使2%戊二醛消毒液既无腐蚀性又稳定的试剂。方法：用0.25%非离子型表面活性剂苄泽35或OP-10替代3%NaHCO3。对取代后的2%戊二醛消毒液采用恒温法在40℃，60℃及80℃进行稳定性试验，留样观察及其对医疗器械的腐蚀性考察。含量测定方法按照《中国医院制剂规范》第1版的方法进行测定。结果：用苄泽35取代后的2%戊二醛消毒液在稳定性试验及留样观察中，消耗H2SO4滴定液（0.05000mol/L）的毫升数仍在限度：3.6-4.4ml之间；浸包5个月后的医疗器械光滑，无斑点。结论：取代后的2%戊二醛消毒液的稳定性高，对医疗器械无腐蚀。     

口腔正畸科、修复科交叉感染的预防研究

因印模等直接与病人唾液、血液、食物残渣接触,成为重要疾病传染源之一。本实验研究紫外灯照射模型、2％戊二醛浸泡印模和(牙合)蜡的消毒效果,结果提示两者均能快速有效地杀灭细菌,切断通过印模等传播疾病的途径。     

新型过氧乙酸溶液应用于消化内镜消毒50例

目的:探讨新型过氧乙酸溶液应用于消化内镜消毒的临床效果。方法:消化内镜100例,随机分成对照组与观察组,每组50例。对照组应用2%戊二醛溶液,观察组应用新型过氧乙酸溶液。结果:观察组总合格率100%与对照组96.00%相比,差异无统计学意义(P>0.05)。结论:新型过氧乙酸溶液应用于消化内镜消毒效果比较可靠,且对内镜无损伤,具有良好的安全性。     

新型过氧乙酸溶液消毒消化内镜的效果评价

目的：重点研究和探讨新型过氧乙酸溶液消毒消化内镜的效果。方法：利用回顾性分析方法,总结我院于2012年1月1日～2013年12月3日天这段时间使用的总计138例消化内镜消毒情况,将其按照消毒方法不同随机分配成2个组,其中对照组患者为69例均采用2％戊二醛进行消毒;观察组患者为69例均采用新型过氧乙酸溶液进行消毒。然后将2组消化内镜消毒效果进行比较,分析探讨2组消化内镜的消毒合格率。结果：观察组消化内镜消毒后总合格率为100．00％,对照组消化内镜消毒后总合格率为94．20％,观察组消化内镜消毒后总合格率好于对照组消化内镜消毒后的总合格率,2组间比较存在显著性的差异（P＜0．05）。结论：新型过氧乙酸溶液消毒消化内镜具有显著的效果,而且显著提高了消化内镜的消毒合格率,为使用消化内镜治疗的患者提供更高的保障,对我国消化内镜的使用发展具有重要价值,值得借鉴和推广。     

Banana peel wastes as a source of tyrosinase useful in the production of l-DOPA

Tyrosinase from the banana peel (TBp) served as a low-cost immobilized biocatalyst for the production of 3, 4-di hydroxyphenyl-l-alanine (l-DOPA). l-DOPA, a dopamine precursor, useful in the management of Parkinson's disease, was produced in improvised reactors. l-DOPA production by the immobilized TBp was optimized via response surface methodology (RSM). l-DOPA productivities obtained at equimolar substrate concentrations and 500 mg of TBp for the packed bed and batch process (BP) were 34.0 ± 2.1 and 15.4 ± 0.9 mg/L/h respectively. The resulting l-DOPA productivity in the BP after the RSM model validation was 63 ± 3.0 mg/L/h. There was a good fit with the model obtained based on the closeness of the predicted and experimental values. After four successive batch processes, about 35% loss in l-DOPA productivity was observed. In conclusion, banana peel served as a relatively cheap and easily available source of tyrosinase for the production of l-DOPA in both batch and packed bed reactors.     

Effect of 0.5% glutaraldehyde disinfection on surface wettability of elastomeric impression materials

Purpose

The purpose of this in-vitro study was to evaluate the effect of 0.5% glutaraldehyde spray disinfection on surface wettability of vinyl polysiloxane and polyether impression materials.

Survival of enveloped and non-enveloped viruses on surfaces compared with other micro-organisms and impact of suboptimal disinfectant exposure

Survival of enveloped and non-enveloped viruses was compared with that of bacteria, yeasts and mycobacteria when dried on the surface of polyvinyl chloride test carriers in the presence or absence of an organic matrix. The efficacy of glutaraldehyde and accelerated hydrogen peroxide (AHP) disinfectants was evaluated. Reovirus, a non-enveloped virus, persisted and had a RF of 2 after 30 days whereas Enterococcus faecalis had an RF of 4 over the same time period. The other test organisms (Sindbis virus, Pseudomonas aeruginosa, Mycobacterium chelonae and Candida albicans) had variable survivals but none survived as long as 30 days. Both glutaraldehyde and AHP were effective at manufactures' recommended dilutions for high-level disinfection. However, only 7% AHP eliminated a glutaraldehyde-resistant strain of M. chelonae. Breakthrough survival was detected at 0.1% glutaraldehyde and 0.05% AHP for all organisms tested. Our data emphasise the need for effective cleaning and disinfection in nosocomial settings to prevent pathogen transmission.     

Fiber alignment imaging during mechanical testing of soft tissues

A method to image fiber alignment during mechanical testing of soft tissues was developed based on quantitative polarized light microscopy. Images were acquired after passing light through a rotating polarizer, a tissue sample, and an effective circular analyzer at multiple polarizer positions during uniaxial mechanical testing. The image set was analyzed off-line using harmonic analysis to generate an alignment image, which contains the direction and strength of alignment at each image pixel. Alignment images of the entire tissue sample were generated every 3–5 s during the mechanical test allowing stress-strain behavior to be correlated with fiber alignment. Loading of fresh tissue-equivalent samples in the direction normal to the initial direction of fiber alignment revealed a spatially inhomogeneous realignment into the loading direction, with most realignment occurring near the free edges undergoing maximum lateral contraction and prior to significant load developing. Glutaraldehyde-fixed samples, in contrast, showed little realignment until yielding occurred. © 2002 Biomedical Engineering Society. PAC2002: 8764Rr, 8780Rb, 8719Rr     

The combined effect of IDA and glutaraldehyde on the properties of human erythrocytes

The effect of IDA and glutaraldehyde on the properties of human erythrocytes was examined by Electron Spin Resonance spectroscopy and fluorescence measurements. In this study glutaraldehyde was used as the agent linking the drug to the erythrocyte membrane. We have demonstrated that idarubicin (IDA) alone caused only negligible changes of the membrane fluidity. When IDA preincubated erythrocytes were treated with glutaraldehyde, the alterations in the fluidity were observed in the polar parts as well as in the deeper regions of the cell membrane. The incorporation of drug and glutaraldehyde into human erythrocytes also caused conformational alterations of membrane cytoskeletal proteins and changes in the internal viscosity of the cells. Our data suggest that glutaraldehyde in idarubicin-pretreated erythrocytes may potentiate the drug toxicity leading to significant perturbations in the organization of the plasma membrane lipids and proteins.     

Thrombogenetic studies of bioprosthetic heart valve surfaces. I. In vitro platelet adhesion in a static system

Contact angle measurements, histological examinations and platelet adhesion tests on native and glutaraldehyde-treated porcine aortic valve leaflets, are reported. Contact angles measured with water or saline on native and treated leaflets do not differ appreciably. Values of less than 10 degrees for both the dry and wet leaflets were observed. Histological examination of the native and fixed tissue surfaces was carried out with both optical and scanning electron microscopy. Native leaflet surfaces appeared to be smoother with longer and straighter fibres beneath the surface than treated leaflets. Platelet adhesion tests were performed with fresh, non-anticoagulated human whole blood as well as with platelet suspension. Static platelet adhesion tests were carried out by depositing droplets of blood on the test surface. The blood droplets were washed off after a contact time of 2 minutes for whole blood and up to 32 minutes for platelet suspension. The adhering platelets were microscopically observed and counted. The platelet density on the native leaflets was found to be significantly higher than on the treated tissues. However, the platelet density did not vary with glutaraldehyde concentration in the range from 0.2 to 1.0% (v/v).