一元过氧乙酸溶液生产工艺和稳定性的研究

目的:一元过氧乙酸溶液生产工艺和稳定性的研究。方法:采用0.1%的8-羟基喹啉作稳定剂和0.1%的AE表面活性剂作乳化剂制备的一元过氧乙酸溶液。结果:一元过氧乙酸溶液稳定性好。结论:一元过氧乙酸溶液质量稳定、可控。     

SARS流行期间过氧乙酸烧伤的病因分析与治疗体会

目的 :总结在预防SARS期间应用过氧乙酸不当导致烧伤的发病特点与治疗经验。方法 :对10 2例过氧乙酸烧伤患者应用美宝湿润烧伤膏 (MEBO)治疗 ,总结其临床特点及治疗体会。结果 :疗程结束时治愈率 10 0 % ,其中Ⅰ度烧伤平均止痛时间 3 78± 2 30分钟 ,皮损消失时间 9 30± 1 5 0小时 ;Ⅱ度烧伤平均愈合时间 6 6 1± 1 37天。 80 %的患者由于长时间接触过氧乙酸而导致烧伤。结论 :在预防SARS期间使用过氧乙酸时应严格按要求使用 ,MEBO对过氧乙酸烧伤有确切疗效     

Decontamination of a siloxane impression material by using 5-aminolevulinic acid activated by photodynamic therapy,microwave irradiation,and hydrogen peroxide

AimThe present study was intended to evaluate the antimicrobial effect of PDT, H₂O_2, and MI on the contact angle, strain-in-compression, and tear strength of siloxane impression material formerly colonized with E. coli, S.aureus and S.mutans.Material and methodsOne hundred and twenty disk-shaped specimens (diameter 10 mm and thickness 2 mm) were prepared by polyvinylsiloxane impression material and inoculated by the American Type Culture Collection (ATCC) of E.coli, S.mutans, and S.aureus in an in-vitro situation. The specimens were broadly divided into six groups then exposed to the various disinfection approaches for 3 min per each group: group 1: Control (no treatment), group 2:PDT 5-ALA, group 3: H₂O₂, group 4: MI, group 5: H₂O₂ + MI, group 6: PDT + MI. After disinfection, assessment of mechanical properties (contact angle, strain-in-compression, and tear strength) of impression materials were instigated. Statistical analysis was executed for CFU/mL (log10) for exposed E. coli, S.aureus, and S.mutans, by two-way ANOVA and Tukey's honestly significant test (p>0.05).ResultsThe highest anti-microbial values against all inspected microbial colonies were unveiled when disinfection was performed in combination i.e., H₂O₂ + MI and PDT + MI and the least cleansing of impression material was seen by the control group as no treatment was provided. Solo application of MI was more effective than control, H₂O₂ and 5-ALA activated by PDT but less active when used in combination method H₂O₂ with MI and PDT with MI. PDT and control group showed the least antimicrobial effectiveness against E. coli (p<0.05)ConclusionDisinfection of impression materials with combination therapies including photodynamic therapy with microwave irradiation and hydrogen peroxide with microwave irradiation displayed highest antimicrobial efficacies against E. coli, S. aureus, and S. mutans with no adverse effects on mechanical properties of impression material.     

Usefulness of hydrogen peroxide enhancement in diagnosis of anal and ano-vaginal fistulas

Our objective was to assess if contrast-enhanced (CE) anal endosonography (AES) with hydrogen peroxide is useful in the diagnosis of anal and ano-vaginal fistulas. A Bruel and Kjaer scanner with a 7.0-MHz transducer was used. After visualization of the fistula tract in non-contrast (NC) AES, hydrogen peroxide was introduced into the fistula tract through the external opening in 22 patients with different types of anal fistulas. Both CE and NC AES revealed 13 transsphincteric, 3 intersphincteric, 2 suprasphincteric and 4 ano-vaginal fistulas. Simple tracts were found in 16 cases and complex in 6 cases in non-contrast AES. The CE AES revealed 19 simple and 3 complex fistulas. Fifteen internal openings visible in NC AES were confirmed in CE AES in 6 cases, which additionally found 11 more internal openings. Surgery confirmed all types of fistulas found in NC and CE AES; however, the latter two found 18 simple and 4 complex fistulas, and 21 internal openings. Both NC and CE AES are able to correctly differentiate types of anal fistulas and are of comparable value in differentiating simple from complex fistulas, although a false-negative result was found in CE AES. In the preoperative assessment of the internal opening, CE AES is superior to NC AES. Electronic Publication     

用高效液相色谱法测定甘草及其制剂中甘草酸含量

应用高效液相色谱法测定了甘草及制剂中甘草酸含量，流动相为甲醇∶０．０６６ｍｏｌ／Ｌ乙酸溶液（６５∶３５），ｐＨ３．０，流速１ｍｌ／ｍｉｎ，检测波长２５５ｎｍ，色谱柱ＮＯＶＡＰＡＫＴＭＣ１８（５μｍ）３．９ｍｍ×１５０ｍｍ，最低检测浓度为０．１μｇ，甘草酸的进样量为２．４４～１９．５６μｇ，精密度２．０８～５．５１，回收率为９６．４０％～９８．２４％。此法提取简单，测定迅速，精密度较好     

连梅饮中黄芩苷和小檗碱的含量测定

目的探讨连梅饮中黄芩苷和小檗碱的含量测定方法。方法采用RP—HPLC／UV法测定连梅饮中黄芩苷和小檗碱的含量;色谱柱：Agilent HC C18柱（250×4．6mm,5μm）;乙腈：0．05mol／L磷酸二氢钾溶液梯度洗脱;检测波长275nm;流速1ml／min。结果黄芩苷在0．448—112μg／ml的浓度范围,小檗碱在0．424～106μg／ml的浓度范围内线性良好：低和高浓度的黄芩苷和小檗碱的精密度（RSD）分别为3．88％、4．84％、4．63％、2．29％;加样回收率分别为（104．3±1.3）％、（97．7±6．9）％;连梅饮中黄芩苷的含量为（2．67±0．012）mg／ml,RSD为0．45％（n=3）;小檗碱的含量为（2．47±0．014）mg／ml,RSD为2．98％（n=3）。结论本方法快速、简便、准确,可用于测定制剂中黄芩苷和小檗碱的含量。     

过氧乙酸空气消毒致化学性角膜结膜炎2例

报道2例过氧乙酸空气消毒导致眼表组织化学性损伤。     

Balance of substances during catalytic oxidation of water admixtures by hydrogen peroxide

Kinetics of CO2 and O2 production was investigated in the following systems: H2O - H2O2 - C6H5OH - siderite, H2O - H2O2 - HCl - siderite, H2O - H2O2 - siderite, H2O - HCl - siderite. A general equation describing the kinetics of phenol oxidation to yield carbon dioxide was derived: Vco2 = k2[C6H5OH]0.55 [H2O2]2 [Fe2+]2, where [Fe2+] denotes iron in the catalyst. The rate of oxygen production in the presence of phenol and siderite was described as Vo2 = k1 [H2O2]1.46. The CO2/O2 ratio in the concentration range 0.5-2.0 M H2O2 increased from 12.8 to 87.2 vol. %. The conversion degree of 0.05 M C6H5OH to carbon dioxide after 35 min oxidation in the presence of 0.5 g of the catalyst and at t = 21 degrees C reached 99.8%. As a result of chemical reactions between hydrogen of the admixtures and oxygen of the oxidizing agent as well as catalytic decomposition of hydrogen peroxide, the amount of pure water in the system increases. Due to reclamation of water containing wastes produced by one person, the total amount of additional water in space mission is estimated to make 204 kg per year.     

Cell killing and DNA damage in Chinese hamster V79 cells treated with hydrogen peroxide

Hydrogen peroxide induces lesions in cells similar to those from ionizing radiation, by a Fenton-type production of hydroxyl radicals. At 4 degrees C significant levels of DAN single-strand breaks (ssb) could be measured using the alkaline elution technique, after a 20-min incubation with 10(-5) mol dm-3 H2O2. Only at higher concentrations of H2O2 (greater than 10(-4) mol dm-3) where the levels of ssb measured corresponded to that induced by more than 18 Gy of X-rays, was any significant cell killing detected in a clonogenic assay. Cell killing was observed to coincide with the measurement of significant levels of DNA double-strand breaks (dsb) using the filter elution technique at pH 9.6. This suggests that dsb and not ssb are important as regards hydroxyl-radical-induced cell kill, as found for ionizing radiation. The correlation of induced dsb with lethal events showed that the predicted lethal effect of the H2O2-induced dsb was approximately 5 times less than that of X-ray-induced dsb. This is compared with data previously obtained which showed differences in the lethality of dsb with the quality of radiation (Prise et al. 1987).     

超氧阴离子和过氧化氢对抗辐射菌增殖的影响

目的探讨不同浓度的超氧阴离子(O2)和过氧化氢(H2O2)与抗辐射菌(Dr)增殖的关系。方法利用细胞色素C还原法测定正常状态下和受不同剂量照射后Dr的O2释放,加入还原型辅酶II(NADPH)氧化酶抑制剂DPI,观察在同样条件下Dr的O2释放和增殖的变化。利用激光共聚焦显微镜测定受照后Dr内H2O2浓度变化。用3H-TdR掺入法测定上述条件下Dr的增殖。结果Dr中O2、H2O2的释放与其增殖有关,较小剂量(<1kGy)照射能刺激Dr增殖并释放O2、H2O2,较大剂量下该效应被抑制。结论适当浓度的O2、H2O2对于Dr的增殖是必要的。     

过氧化氢导致肠上皮细胞线粒体编码三磷酸腺苷合成酶基因损伤的研究

目的 探讨过氧化氢（H2O2）对肠上皮细胞线粒体DNA（mtDNA)编码的三磷酸腺苷（ATP）合成酶基因的损伤作用。方法 肠上皮细胞株（SW－480）采用4mmol/L H2O2处理后进行mtDNA的提取，对ATP合成酶的ATPase6亚基、ATPase8亚基基因进行聚合酶链反应（PCR）扩增，并对PCR产物直接进行测序；同时于该时相点测定酶活性。结果 ATPase 8亚基基因在8385－8543段出现大范围的点突变；H2O2可导致mtDNA突变基因所编码的ATP合成酶活性明显下降。结论 H2O2可明显损伤mtDNA编码的ATP合成酶基因，这种损伤作用最终导致其编码的酶蛋白活性明显下降。     

D-amphetamine-induced hydrogen peroxide production in skeletal muscle is modulated by monoamine oxidase inhibition

The aim of this paper was to study the influence of d-amphetamine administration as a sympathomimetic drug on the synthesis of hydrogen peroxide (H2O2) in mouse soleus muscle and to investigate the modulating effects of pargyline, an inhibitor of monoamine oxidase (MAO) in this context. Charles River mice were assigned to four groups: Control, d-amphetamine treated, pargyline treated, and amphetamine + pargyline treated. Their soleus muscles were removed 0, 15, 30, 60, and 120 min after treatment. The amount of hydrogen peroxide formation within the muscles was estimated using an indirect method. The control data showed a continuous production of hydrogen peroxidase. Pargyline administration lead to an initial increase of H2O2 production that later faded below control levels. Administration of amphetamine finally stimulated H2O2 production much above control levels. When combining amphetamine and pargyline treatment, H2O2 production was accelerated in the initial phase but dropped to control levels at 30 min. It is concluded that in skeletal muscle MAO is an important source of hydrogen peroxide production triggered by amphetamine administration and that this tissue plays a hitherto not described role in oxidizing circulating biogenic monoamines.     

Determination of hydrogen in liquids by neutron thermalization

A modified neutron thermalization technique for determining the hydrogen density in liquids flowing through pipelines is presented. The measuring head includes a neutron source emitting 5 × 10⁵ neutrons/s, BF₃-filled proportional counter and a special housing made of moderating, reflecting and absorbing materials.The technique is particularly applicable to monitoring the concentration of H₂SO₄ in water solutions. A reproducibility of 0.5% can be easily achieved for determining the H₂SO₄ content ranging from 80 to 100 wt%.