水相合成CdTe量子点荧光光度法测定硫酸庆大霉素

目的:基于CdTe量子点的荧光淬灭现象,建立一种简便、经济和高灵敏度的检测硫酸庆大霉素的新方法。方法:以巯基乙酸（TGA）为稳定剂,在水相中合成CdTe量子点,并用荧光分光光度计、红外光谱仪、透射电镜对其进行表征。实验过程中,优化了CdTe量子点TGA、镉、碲三者之间的比例,考察了不同pH与回流时间对量子点荧光性质的影响。通过测定CdTe量子点荧光强度的下降,实现了对硫酸庆大霉素注射液浓度的测定。结果:合成了荧光发射峰在607 nm、粒径在4.0 nm左右的CdTe量子点。硫酸庆大霉素对CdTe 量子点的荧光有淬灭作用,在pH=7.4的磷酸盐缓冲体系中,硫酸庆大霉素的浓度在0.10～2.00 mg/L范围时,量子点荧光强度比值与硫酸庆大霉素浓度符合Stern -Volmer方程且相关系数R²=0.9989。结论:该方法灵敏度较高,快速简便,可用于硫酸庆大霉素浓度的测定。     

蛋白结合硫酸吲哚酚对单核细胞趋化功能的影响

目的 研究蛋白结合硫酸吲哚酚(indoxyl sulfate,IS)对单核细胞趋化功能的影响及其可能机制.方法 以4％人血白蛋白(human serum albumin,HSA)结合游离的IS制备蛋白结合IS,高效液相色谱法(HPLC)检测其蛋白结合率.CCK-8法检测人单核细胞(THP-1)经不同浓度的游离IS和蛋白结合IS分别作用24 h后细胞增殖能力的变化.200 μmol/L游离IS和蛋白结合IS分别孵育THP-1细胞24 h后,Transwell小室法检测THP-1细胞趋化能力;ELISA法检测细胞培养上清中单核细胞趋化蛋白-1(MCP-1)浓度;流式细胞术检测THP-1细胞上CC类趋化因子受体2(CCR2)的表达水平.结果 成功制备蛋白结合IS,其蛋白结合率约为90％;蛋白结合IS和游离IS均可抑制THP-1细胞增殖,且蛋白结合IS对THP-1细胞的增殖抑制作用具有浓度依赖性(P＜0.05);蛋白结合IS和游离IS均可增强THP-1细胞的趋化活性(P＜0.05);蛋白结合IS和游离IS均可使THP-1细胞的MCP-1和CCR2表达上调(P＜0.05).结论 蛋白结合IS同游离IS一样,可通过上调MCP-1及CCR2的表达增强单核细胞的趋化功能.     

Acute irritant contact dermatitis: recovery time in man

Our understanding of the details of the recovery time of acute irritant contact dermatitis (ICD) is limited. We examined skin reactivity to a model surfactant, sodium lauryl sulfate (SLS). on previous acute ICD and normal sites over time with visual grading and noninvasive instruments. Acute ICD was induced on the upper arms of 18 volunteers (aged 30 to 51 years) by occluded application of 1% SLS for 24 h. Previous ICD and normal sites were provoked by occluded application of 2% or 7.5% SLS 30 min daily 4 consecutive days. Skin reactivity was assessed daily by visual erythema scoring (VES), transepidermal water loss (TEWL), skin color reflectance (SCR) and electrical capacitance (EC). Skin function of previous ICD sites assessed, by VES, TEWL. SCR, and EC did not normalize until 2 weeks later: all parameters of previous ICD returned to normal after 3 weeks. While skin reactivity to 2% und 7.5% SLS showed no differences between previous ICD and normal sites at 4 weeks, differences of irritant reactivity especially 7,5% SLS between previous ICD and normal sites were significant at 3 weeks post-provocation. Our results demonstrate that irritation evaluated with irritant provocation was long-lasting, even though skin functional parameters assessed by various bioengineering instruments returned to normal. Complete recovery of skin function including irritability after acute ICD induced by 1% SLS was achieved approximately 4 weeks later. The date were generated with a model surfactant: it remains to be determined whether similar responses will be noted with chemicals of different physicochemical properties.     

Capacitively coupled electrical stimulation of bovine growth plate chondrocytes grown in pellet form

Pellets formed from isolated bovine growth plate chondrocytes were grown in various capacitively coupled electrical fields. The signals chosen were 0, 10, 100, 250, 500, 750, 1,000, and 1,500 V peak-to-peak, 60 kHz. The effect on cell proliferation and matrix production of these different voltages was determined by [3H]thymidine and [35S]sulfate uptake, respectively, Cyclic AMP assays were done to determine if increases in either thymidine or sulfate uptake were associated with changes in cAMP levels. Significantly increased cell proliferation occurred at 500, 750, and 1,000 V peak to peak. The calculated electric fields were 1.5 to 3.0 x 10(-2) V/cm. Proliferation was significantly inhibited at 1,500 V peak-to-peak with a calculated field of 4.5 x 10(-2) V/cm. Little if any change was seen in cAMP levels at 30 or 60 min following application of the appropriate electric signals.     

Human cutaneous irritation: induced hyporeactivity

The variation in human skin response to sodium lauryl sulfate (SLS) was determined with patch and open applications. Reactions in different subjects and in multiple simultaneous patch tests were compared. Skin responses were assessed with visual scoring (VS), laser Doppler velocimetry (LDV) and transepidermal water loss (TEWL). Previous open, unpatched SLS exposure decreased patch test reactivity to 1% SLS assessed with VS (p less than 0.05) or LDV (p less than 0.05). Corresponding TEWL alteration was inconstant. Variation in reactivity at different test sites in multiple simultaneous tests was considerable, though less than the variation at different test times (p less than 0.05). Inter-subject variation in test reactivity was greater than the variation between different test times or adjacent test sites. Repeated open applications and the subclinical dermatitis appear to have produced a hyporeactive state. The results suggest that non-specific skin inflammation is elicited by multiple factors, e.g., stratum corneum integrity and vascular reactivity. Their balance determines the ensuing reactions. The induced hyporeactivity may be one of many causes of false negative diagnostic patch tests.     

围术期输注硫酸镁对全麻术后吗啡用量的影响

目的观察围术期输注硫酸镁对全麻术后吗啡用量的影响。方法选择40例ASAⅠ-Ⅱ级,拟在全麻下行全子宫切除术的患者,随机分为对照组(NS组)和硫酸镁组(MG组)。MG组术前静脉给予25%MgSO4负荷剂量25mg/kg(即0·1ml/kg),继以200mg/h持续输注至术后48h。NS组给予同等容量的生理盐水以同样技术予以输注。术后应用吗啡静脉自控镇痛(PCIA),记录患者首次要求镇痛的时间(患者主观VAS评分>4cm时),术后4、8、18、24、48h疼痛评分(VAS)、镇静评分(OAA/S)、吗啡用量及术后恶心、呕吐情况。结果从手术结束到患者首次要求镇痛的时间,MG组30·2±5·2min比NS组20·0±4·3min显著延长(P<0·01)。MG组术后48h内吗啡的总用量22·8±4·8mg,显著低于NS组27·0±6·8mg(P<0·01)。术后恶心呕吐的发生率MG组与NS组分别为10%和30%(P<0·05)。结论全麻下行子宫切除术的病人,围术期输注硫酸镁可延长患者术后首次要求镇痛的时间,减少术后48h内吗啡的用量及术后恶心呕吐的发生率。     

影响主动载药法制备硫酸长春新碱脂质体包封率的因素

 目的采用主动载药法制备硫酸长春新碱脂质体,考察包封率的影响因素。方法采用阳离子交换树脂分离脂质体与游离药物,用HPLC测定包封率;考察了温度、pH调节剂、药脂比、包衣辅料及制备工艺对包封率的影响。结果脂质体的包封率随温度的升高而增加、随药脂比增大而降低、Na₂HPO₄最适合作pH调节剂;以pH梯度法和(NH₄)₂SO₄梯度法制备的脂质体包封率分别为86.9%,70.8%;加入聚乙二醇单甲醚2000胆固醇琥珀酸酯(methoxypolyethyeneglycol2000cholesterylsuccinate,CHS-PEG₂₀₀₀),包封率提高到92.8%,97.6%。结论主动载药法适于制备硫酸长春新碱脂质体;温度,pH调节剂和药脂比是影响包封率的重要因素。     

Combined effects of irritants and allergens. Synergistic effects of nickel and sodium lauryl sulfate in nickel- sensitized individuals

Knowledge of the combined effects of irritants and allergens is of interest with respect to accurate risk assessment. The threshold for elicitation of allergic contact dermatitis in previously sensitized individuals may theoretically be markedly influenced by the simultaneous presence of irritants and allergens. Combined exposures have, however, only been studied infrequently. In the present study, the combined effect of an irritant and an allergen was evaluated in a dose-response designed experimental study. 20 nickel-sensitized subjects were exposed to patch testing with varying concentrations of NiCl2 (nickel chloride) and sodium lauryl sulfate (SLS) alone and in combination. Evaluation of skin reactions was performed by colorimetry, measurement of transepidermal water loss and clinical evaluation, and the data were analyzed by logistic dose-response models. A synergistic effect was found of combined exposure to NiCl2 and SLS, as compared to each of the substances applied separately, as evaluated by colorimetry and clinical scoring. This means that the effect produced by the combined exposure was substantially greater than the effect produced by either of the substances alone. A synergistic effect of combined exposure on skin barrier impairment was not found, since the barrier function is significantly influenced by SLS-exposure only and not by NiCl2. Concentration limits are used by industry and government agencies to protect consumers. The present results clearly illustrate that elicitation thresholds and concentration limits may be influenced considerably by combined exposure to allergens and irritants.     

高效液相色谱法测定硫酸吗啡缓释栓含量

摘 要 目的： 制备硫酸吗啡缓释栓剂,采用高效液相色谱法测定硫酸吗啡缓释栓剂的含量。方法: 采用Eclipse XDB C18柱（150 mm×4.6mm,5μm）;以甲醇 庚烷磺酸钠醋酸溶液（取庚烷磺酸钠2.02 g,加水适量溶解,加冰醋酸5 ml,加水稀释至1 000 ml,摇匀）（50∶50）为流动相;流速为1.0 ml·min^-1;检测波长:233 nm;柱温:25℃;进样量:10 μl。结果: 3批样品中硫酸吗啡平均含量为99.9%,在4.18～86.60 μg·ml^-1浓度范围内线性关系良好(r=0.999 3),平均回收率100.6%,RSD=1.58%(n =9)。结论:该检测方法灵敏、快速、结果准确,适用于硫酸吗啡缓释栓剂质量控制。     

矿物药玄明粉与无水硫酸钠的构效对比研究

目的 对比研究矿物药玄明粉与无水硫酸钠结构与药效差异,探索二者的作用机制。方法 采用AXIOS型X射线荧光光谱法对二者结构进行比较;采用小鼠胃排空、肠推进模型和复方地芬诺酯所致便秘模型对二者药效进行比较。结果 玄明粉有正交和立方两种晶型,无水硫酸钠只有正交晶型;除共有化学组成外,玄明粉还含有Al₂O₃、K₂O、SrO、ZnO、Cl^?,无水硫酸钠仅有Fe₂O₃;药效对比实验中,发现二者对小肠运动的影响具有显著性差异（P＜0.01）。结论 玄明粉与无水硫酸钠在结构和药效上存在一定的差异,实验结果可为临床应用提供参考依据。