壳聚糖衍生物纳米粒子的制备及对体内放射性锶的促排作用

目的制备壳聚糖-乙二胺四乙酸(CTS-EDTA)纳米粒,通过动物实验观察壳聚糖-乙二胺四乙酸纳米粒(CEC-Nano)对放射性锶的促排效果尤其是预防性给药的促排效果。方法通过N-酰化反应连接壳聚糖与乙二胺四乙酸纳,并将反应产物与TPP利用离子凝胶法制成纳米粒。通过染毒前与染毒后给药,比较其治疗性与预防性促排效果。结果 CTS-EDTA纳米粒通过透射电镜观察显示可得到粒度较为均一的球形纳米粒子。体内实验表明,小鼠骨头尤其是颅骨的放射性锶含量在预防给药治疗组比对照组和即刻给药治疗组明显低(P<0.05),小鼠体内整体放射性锶残留量也比其他组明显低(P<0.05)。结论 CEC-Nano对体内放射性锶具有良好的促排效果尤其是预防性给药治疗促排效果更好。     

食物中酚类对亚硝胺体内外合成的影响

N-亚硝基化合物可在体内体外由前体物形成。已知抗坏血酸、生育酚、抗氧化剂、含硫氨基酸及还原糖类可抑制N-亚硝化反应,从而阻断N-亚硝基化合物合成的作用,它们都是通过降低亚硝化剂(NO_2~-)的含量而发生作用的。N-亚硝化的反应动力学如下: 2 HNO_2(?)N_2O_3+H_2O (1) R_2NH_2~+(?)R_2NH+H~+ (2) R_2NH+N_2O_3→R_2NNO+HNO_2 (2) d[R_2NBO]/dt=k[R_2NH][N_2O_3]=k[R_2NH][NO_2~-]~2     

碘对环孢霉素A抑制免疫性甲状腺炎拮抗作用

目的研究碘过量对环孢霉素A(Cyclosporin A,CsA)抑制实验性自身免疫性甲状腺炎(EAT)形成的拮抗作用,进一步探讨碘在自身免疫性甲状腺炎发病中的作用。方法给予Lewis大鼠不同碘摄入量,EAT诱发组和EAT+CsA组均用猪Tg进行免疫诱发EAT形成,EAT+CsA组于首次免疫后的第10 d开始腹腔注射CsA,5 mg/(kg.d),非EAT对照组不做任何处理,末次免疫后2周处死各组大鼠并取材。观察大鼠甲状腺组织的病理改变和炎细胞浸润程度,采用放射免疫法检测血清中甲状腺球蛋白抗体(TG-Ab)、甲状腺过氧化物酶抗体(TPO-Ab)和T3、T4水平。结果(1)不同碘摄入量的EAT组和EAT+CsA组的大鼠甲状腺组织均有不同程度的炎性细胞浸润,非EAT对照组大鼠甲状腺未见明显炎性细胞浸润。EAT组大鼠甲状腺的炎症反应重于EAT+CsA组,诱发EAT的2组甲状腺的炎症反应随碘摄入量的增加而加重。(2)EAT组和EAT+CsA组的血清中自身抗体TG-Ab和TPO-Ab水平均高于对照组(P<0.05),EAT+CsA组的TG-Ab和TPO-Ab水平均低于EAT组,2组自身抗体水平亦随着碘摄入量的增加有升高趋势。(3)100倍碘水平的各组T4水平下降,各组的血清T3含量比较差异无统计学意义。结论增加碘的摄入量会明显加重EAT的炎症反应,促进EAT的形成和发展;CsA对EAT的形成及甲状腺自身抗体的产生有一定的抑制作用,碘过量可以拮抗CsA的这种作用,且随碘摄入量的增加拮抗效应增强;碘摄入过多可以抑制甲状腺激素的合成和释放。     

血尿酸、C-反应蛋白与脑血管疾病关系的研究

目的探讨血尿酸水平、C-反应蛋白与脑血管疾病的关系的研究。方法采用OLYMPUSAu400全自动生化分析仪测定191例脑梗死及84例脑出血患者急性期血尿酸水平、C-反应蛋白含量，并与117例正常人对照比较。结果脑梗死组和脑出血组血尿酸、C-反应蛋白含量均明显高于对照组（P〈0．05）。结论高水平的血尿酸及C-反应蛋白在脑血管疾病的发病机制中起一定的作用，可增加脑血管疾病的发病率。     

酰卤作为酰化剂氮原子上的酰化反应在药物合成中的应用

以酰卤作为酰化剂在氮原子上的酰化反应在药物合成中的应用非常之多,酰卤为活泼的酰化剂,与胺反应强烈快速,其中以酰氯应用最多,为了获得好收率,必须不断出去生成的卤化氢以防止其与胺成盐,中和卤化氢可采用过量胺或加入有机碱吡啶、三乙胺甚至强碱性季铵化合物。本文介绍在药物氟他胺、氟他唑仑、卡托普利、曲尼司特、盐酸托卡尼中以酰卤作为酰化剂在氮原子上的酰化反应在药物合成中的应用以及该单元反应的操作流程。     

功夫菊酯半抗原的合成及结构表征

目的为了建立功夫菊酯残留的酶联免疫分析方法,设计并合成了功夫菊酯的半抗原。方法利用功夫菊酸和α-氰基-(3-苯氧基)苄醇通过酰化、水解、酯化多步反应合成了功夫菊酯的半抗原:2,2-二甲基-3-(2-氯-3,3,3-三氟-1-丙烯基)环丙烷羧酸-α-(N-丁酸基)-甲酰氨-3-苯氧基苄酯。结果通过质谱和核磁鉴定了半抗原的结构,证明所合成的产物为目标产物。结论合成的半抗原分子保留了功夫菊酯结构的主要特点,为进一步建立功夫菊酯的酶联免疫分析方法提供了研究基础。     

中华猕猴桃的防癌作用(三)在模拟人胃液中对N-亚硝酰胺合成的阻断作用——Ames试验

本文用Ames试验的方法研究了中华猕猴桃汁对N-亚硝酰胺体外合成的阻断作用。 在模拟人胃液的条件下,亚硝酸钠和甲基硝基胍能反应生成N-甲基-N′-硝基-N亚硝基胍,在Ames氏平皿掺入试验中引起鼠伤寒沙门氏菌TA100菌株的突变反应,有明显的剂量反应关系。当亚硝酸钠浓度为50mM,甲基硝基胍为100mM时,突变菌落数高达4327个/皿,为自发回变的19.94倍。中华猕猴桃汁能阻断N-甲基-N′-硝基-N-亚硝基胍合成,抑制突变反应。在亚硝酸钠浓度为22.2mM,甲基硝基胍为44.4mM时,猕猴桃汁能完全阻断N-甲基-N′-硝基-N-亚硝基胍的合成,致突变反应为阴性。而不加猕猴桃汁的同浓度反应体系引起的突变反应为自发回变的12.59倍。桃汁组低于此浓度的反应体系结果皆是阴性,而对高于此浓度的反应体系,猕猴桃汁不能完全阻断N-甲基-N′-硝基-N-亚硝基胍合成,但能明显抑制突变反应。对中等浓度的反应体系,与桃汁含量相同的抗坏血酸溶液亦能部分阻断N-甲基-N′-硝基-N-亚硝基胍的合成,但作用低于猕猴桃汁。实验结果证明猕猴桃汁阻断N-甲基-N′-硝基-N-亚硝基胍体外合成的作用明显优于同浓度抗坏血酸溶液。 在相同实验条件下,单独的亚硝酸钠或甲基硝基胍均无致突变作用。经薄层层析方法定性分析,反应生成物是N-甲基-N′-硝基-N-亚硝基胍。     

促智药普拉西坦的合成

氯乙酰氯与N,N-二异丙基乙二胺在碱性条件下进行酰化,所得中间体与2-吡咯烷酮烷基化,得普拉西坦。     

白藜芦醇对妊娠期至性成熟期亚砷酸钠暴露子代小鼠学习记忆和脑氧化应激损伤的保护作用

目的 研究白藜芦醇（RES）对妊娠期至性成熟期亚砷酸钠（NaAsO2）暴露子代小鼠发育早期学习记忆和脑氧化应激的影响，探讨砷暴露所致学习记忆受损的可能机制及防治措施。方法 将36只妊娠小鼠分为对照组（12只）及染砷组（24只，饮用含60 mg/L NaAsO2水），其子代小鼠在断乳后至实验结束以饮水方式染砷。仔鼠出生后28 d饮水染砷同时给予RES灌胃干预：来自对照组窝别的仔鼠随机分为对照组和50 mg/kg RES组，来自染砷组的仔鼠随机分为NaAsO2组、NaAsO2+（25、50、100 mg/kg）RES组，每组6只。RES灌胃干预4周，进行水迷宫实验，取各组仔鼠血清和脑组织测定还原型谷胱甘肽（GSH）、超氧化物歧化酶（SOD）、乳酸脱氢酶（LDH）和丙二醛（MDA）水平。结果 从训练第4天起，NaAsO2组仔鼠寻找平台潜伏期显著长于对照组，NaAsO2+RES组仔鼠寻找平台潜伏期显著短于NaAsO2组（P<0.05）；空间探索时NaAsO2组仔鼠在目标象限停留时间显著短于对照组，NaAsO2 +（25、50 mg/kg）RES组仔鼠在目标象限停留时间显著长于NaAsO2组（P<0.05）。与对照组相比，NaAsO2组仔鼠血清和脑组织中SOD和GSH活性显著下降，LDH和MDA水平明显升高；与NaAsO2组相比，NaAsO2 + RES组血清及脑组织中SOD和GSH活性显著升高，LDH和MDA水平显著下降；差异均有统计学意义（P<0.05）。结论 RES可改善砷暴露子代小鼠的氧化应激损伤，从而可能改善砷所致学习记忆能力损伤。     

茶多酚对甲基汞致大鼠大脑皮质神经元氧化损伤的防护作用

目的探讨茶多酚(tea polypheonols,TP)对甲基汞(methylmercury,MeHg)所致大鼠大脑皮质神经元氧化损伤的防护作用及机制。方法进行大鼠大脑皮质神经元原代培养,细胞成熟后给予0.01、0.1、1、2μmol/L MeHg分别处理0.5、1、3、6、12 h,通过测定培养液中乳酸脱氢酶(lactate dehydrogenase,LDH)活力来进行MeHg细胞毒性分析;根据测定结果选择最具代表性的1μmol/L MeHg暴露6 h作为MeHg染毒组。应用同样方法进行TP预处理组选定,向培养液中分别加入终浓度为5、10、20及40μmol/L TP,分别预处理0.5、1、3及6 h后,再加入终浓度为1μmol/L MeHg,继续培养6 h后测定培养液LDH漏出,根据实验结果选定5、10、20μmol/L预处理3 h作为TP预处理剂量及时间;细胞经各剂量TP预处理后,再暴露于1μmol/L MeHg 6 h,测定神经元细胞凋亡率、非蛋白巯基(non-protein sulfhydryl,NPSH)含量、活性氧簇(reactive oxygen species,ROS)水平及Na+-K+-ATPase和Ca2+-ATPase活力。结果与对照组比较,随着染MeHg剂量的升高,培养液中LDH活力逐渐升高,呈现剂量和时间依赖性的效应关系。TP预处理后,LDH活力逐渐降低,在10、20μmol/L TP预处理组显著降低(P0.05或P0.01);1μmol/L MeHg导致神经元凋亡率显著升高,NPSH含量显著降低,ROS水平显著升高,Na+-K+-ATPase和Ca2+-ATPase活力显著降低,差异均有统计学意义(P0.01),TP预处理对上述指标的拮抗作用呈现剂量-效应关系,差异均有统计学意义(P0.05或P0.01)。结论 TP对MeHg所致大鼠大脑皮质神经元氧化损伤具有一定的防护作用。     

Preliminary studies of an 18-crown-6 ether modified magnetic cation exchange polymer in rapid (90)Sr bioassay

A cation exchange polymer resin embedded with magnetic nanoparticles and modified with crown ether was developed for urinalysis to rapidly monitor levels of (90)Sr exposure in humans who have been involved in a nuclear event. Invention of the resin matrix of 2-acrylamido-2-methyl-1-propanesulfonic acid cross-linked with divinylbenzene incorporated a Sr(2+) chelating agent, di-tert-butyl-cyclohexano-18-crown-6 through surface immobilization using a molecular modifier 1-octanol. The performance of these magnetic cation exchange resin particles was investigated by separating (90)Sr in the presence of (90)Y progeny. Masking agents and precipitants were examined to ascertain that sodium hydroxide at pH 7.5 was capable of selectively removing 89 ± 2% (90)Y before subsequent (90)Sr uptake. Preliminary investigations in rapid urinalysis were successful in isolating 83 ± 2% (90)Sr when pH was optimized to 9, with a sample turnover time <2 h, which is promising for radiological emergencies.     

TiO2复合抗菌材料抗菌性能的研究

[目的]了解TiO2复合抗菌材料的抗菌性质.[方法]TiO2作为载体,按照不同的掺杂比例制备Sr2 ,Ag 的复合无机抗菌剂.采用抑菌圈试验法和细菌总数测定法来检测其抗菌性能.[结果]负载Sr2 ,Ag 的复合抗菌材料都具有一定的抗菌性能.其中负载Ag 的TiO2复合抗菌材料抗菌性能较强.负载6%Ag 的TiO2复合材料添加量为0.75g/L时,仅仅作用1.5 h抑菌率就可以达到100%. [结论]该复合抗菌材料具有广泛的应用前景.     

Supplemental Escherichia coli phytase and strontium enhance bone strength of young pigs fed a phosphorus-adequate diet

Young pigs represent an excellent model of youth to assess potentials of dietary factors for improving bone structure and function. We conducted 2 experiments to determine whether adding microbial phytase (2,000 U/kg, OptiPhos, JBS United) and Sr (50 mg/kg, SrCO3 Alfa Aesar) into a P-adequate diet further improved bone strength of young pigs. In Expt. 1, 24 gilts (8.6 +/- 0.1 kg body wt) were divided into 2 groups (n = 12), and fed a corn-soybean-meal basal diet (BD, 0.33% available P) or BD + phytase for 6 wk. In Expt. 2, 32 pigs (11.4 +/- 0.2 kg) were divided into 4 groups (n = 8), and fed BD, BD + phytase, BD + Sr, or BD + phytase and Sr for 5 wk. Both supplemental phytase and Sr enhanced (P < 0.05) breaking strengths (11-20%), mineral content (6-15%), and mineral density (6-11%) of metatarsals and femurs. Supplemental phytase also resulted in larger total bone areas (P < 0.05) and a larger cross-sectional area of femur (P = 0.06). Concentrations of Sr were elevated 4-fold (P < 0.001) in both bones by Sr, and moderately increased (P = 0.05-0.07) in metatarsal by phytase. In conclusion, supplemental phytase at 2000 U/kg of P-adequate diets enhanced bone mechanical function of weanling pigs by modulating both geometrical and chemical properties of bone. The similar benefit of supplemental Sr was mainly due to an effect on bone chemical properties.     

Carpal tunnel syndrome (CTS) in the Piedmont Region: regional incidence and prevalence of CTS based on hospital records of patients who underwent surgery

BACKGROUND: Carpal tunnel syndrome (CTS) is the most frequent entrapment neuropathy of the upper extremities. Despite CTS being a priority for public health, only a few studies have investigated the prevalence and incidence in the general population. In Italy, administrative data are available only for CTS cases which were judged work-related by the Workers Compensation Board. These data indicate a steady increase in CTS over the last decade. Hospital admission archives (SDO) also contain information on CTS patients who underwent surgery. OBJECTIVES: To determine: 1) the incidence and prevalence of first CTS, based on hospital records of patients who underwent surgery in the Piedmont Region; 2) to describe the geographical and temporal variation. METHODS: Crude and standardized incidence rates of CTS were computed for the period 2002-2003; geographical variation was assessed using bayesan estimators to detect spatial clusters. Crude and standardized prevalence rates of first hospitalization were calculated for every two-year period between 1996 and 2003. RESULTS AND CONCLUSIONS: The crude incidence rate was 227.2 (C.I.95% 221.9-232.7) per 100,000 women and 54.4 (C.I. 95% 51.9-57.1) per 100,000 men. The prevalence of first hospitalization was very high and varied widely by geographic area. Two possible explanations for such wide variation between areas include differences in exposure to risk factors for CTS and in the diagnostic criteria used. The increasing prevalence over time was only partly explained by an increase in work-related cases. The development of standardized diagnostic criteria would improve understanding of the effect of workplace exposures on CTS. The number of new cases per year in Piedmont was estimated at 1,500, much higher than the compensation claims related to CTS. Health education campaigns addressed to general practitioners on compensation law could improve reporting to the workers' compensation board.     

Prevalence, incidence and risk factors of carpal tunnel syndrome in a large footwear factory

The study was conducted to assess the prevalence and incidence of carpal tunnel syndrome (CTS) in a large modern footwear factory and to identify factors predictive of CTS. To this end, 199 workers were examined in 1996, and 162 of them were re-examined in 1997. Ergonomic and psychosocial risk factors of CTS were assessed by workpost analysis and self-administered questionnaire. The prevalence of CTS at baseline in 1996 and in 1997 was 16.6% (95%CI: 11.4-21.7) and 11.7% (95%CI: 6.7-16.8), respectively. The incidence rate of CTS in 1997 was 11.7% (95%CI: 6.7-7.8). No specific type of job performance was associated with CTS. Obesity (OR = 4.4; 95%CI: 1.1-17.1) and psychological distress at baseline (OR = 4.3; 95%CI: 1.0-18.6) were strongly predictive of CTS. Rapid trigger movements of the fingers were also predictive of CTS (OR = 3.8; 95%CI: 1.0-17.2). A strict control of thework by superiors was negatively associatedwith CTS (OR = 0.5; 95%CI: 0.2-1.3). The prevalence and incidence of CTS in this workforce were largely higher than in the general population and numerous industries. The study highlights the role of psychological distress in workers exposed to a high level of physical exposure and psychological demand.     

螯合剂与金属硫蛋白对铀的竞争结合作用

目的 通过探讨螯合剂与金属硫蛋白（MT）竞争结合铀（U）（VI）的作用,建立铀促排螯合剂体外筛选的新方法。方法 采用竞争ELISA法,96孔酶标板经MT抗原包被、U（VI）或Zn²⁺预处理、螯合剂（CBMIDA-CaNa₂、BPCBG和DTPA-CaNa₃）处理、MT抗体免疫结合、HRP偶联二抗结合及OPD显色反应后,在波长490 nm处检测吸光度值以评价螯合剂与MT竞争结合U（VI）、Zn²⁺的能力。结果 本反应体系的吸光度值随MT质量浓度和MT抗体浓度增加而增加,其中最佳MT抗原包被浓度和MT抗体浓度均为2 μg/mL。与Zn²⁺的作用相似,U（VI）亦可使反应体系的吸光度值随其浓度增加而降低,其中最佳U（VI）和Zn²⁺浓度均为300 μg/mL。加入CBMIDA-CaNa₂和BPCBG则能明显提高U（VI）处理体系的吸光度值,CBMIDA-CaNa₂的作用强于BPCBG,而DTPA-CaNa₃则无明显作用;各螯合剂与MT竞争结合U（VI）能力的强弱顺序与以往细胞和动物U（VI）促排实验的结果相吻合。这3种螯合剂对Zn²⁺处理体系的吸光度值均无明显影响。结论 CBMIDA-CaNa₂和BPCBG能有效竞争结合于MT上的U（VI）,DTPA-CaNa₃无明显作用,竞争ELISA法可作为体外筛选U（VI）促排螯合剂的方法,具有简便、快速和高通量的优势。     

Prevalence and incidence of carpal tunnel syndrome in a meat packing plant

OBJECTIVES: To determine prevalence and incidence of carpal tunnel syndrome (CTS) in a modern meat packing plant. The secondary objective was to explore the relation between ethnicity and CTS. METHODS: Six hundred and sixty five workers were interviewed and examined to find the prevalence of CTS. Subsequently, 421 workers without CTS were followed up and examined at a median interval of 253 days; of those, 333 remained without CTS and were again examined at a median interval of 148 days. RESULTS: The prevalence and incidence of CTS was 21% and 11/100 person-years, respectively. The incidence for Asian mixed, white, and other ethnicities was 12.0, 12.2, and 7.2 cases/100 person- years, respectively. The observed incidence for men and women was 9.7 and 18.4 cases/100 person-years, respectively. This difference was not quite significant (p = 0.068) with an estimated relative risk (women v men) of 1.9 (95% confidence interval (95% CI) 0.9 to 3.8). The interaction between sex and use of tools was significant (p = 0.04), however, although the relative risk for CTS in women who used tools was 4.2 the numbers were small and not significant. The relative risk for men who used tools was 0.64 and not significant. The percentage of incident cases with comorbid disease was only 6.3% (3/47). CONCLUSIONS: The prevalence and incidence of CTS in this workforce were higher than in the general population. However, the prevalence of CTS in this modern, mechanised plant was not significantly different from that reported in older plants. No relation was found between ethnicity, age, body mass index, and CTS for either prevalence or incidence. Comorbid disease among the cases of CTS is significantly less than that found in other industry.     

Influence of trans-1,2-diaminocyclohexane structure and mixed carboxylic/phosphonic group combinations on samarium-153 chelation capacity and stability

A simple procedure was developed to compare chelating agents for (153)Sm complexes as a preliminary step to synthesise bifunctional analogues. Several variables affecting the efficiency of complex stability were investigated, such as the pre-organisation concept, cavity size, and the nature of coordination sites. Four semi-rigid agents incorporating carboxylic and/or phosphonic groupings fixed at trans-1,2-diaminocyclohexane were evaluated for their (153)Sm chelation properties, and competition studies were performed. Data on the stability of the best chelating agent compound 3: trans-cyclohexane-1,2-bis(aminomethylphosphonic)-N,N'-bis(ethyl-2-iminodiacetic acid) in human serum are presented.     

Resistance of Lactobacillus plantarum KCTC 3099 from Kimchi to oxidative stress

The antioxidative capacity of two lactic acid bacteria isolated from Kimchi, a Korean fermented food, was evaluated by measuring the resistance to reactive oxygen species (ROS) and compared with that of Lactobacillus rhamnosus GG as a positive control. Both intact cells and cell-free extracts of Lactobacillus plantarum KCTC 3099 exhibited higher antioxidative activity in inhibiting lipid peroxidation among the strains evaluated with an inhibitory level of 38.6% and 48.5%, respectively. To evaluate the resistance of the two lactic acid bacteria to ROS, we tested their survival in the presence of 1 mM hydrogen peroxide, 0.4 mM hydroxyl radicals, and superoxide anions induced by 10 mM paraquat. L. plantarum KCTC 3099 was viable even after 8 hours in the presence of both 1 mM hydrogen peroxide and 0.4 mM hydroxyl radicals. Moreover, the survival of L. plantarum KCTC 3099 was not affected by superoxide anions generated by using paraquat, indicating that it has resistance to superoxide anions. To define the antioxidative mechanism, superoxide dismutase (SOD) and metal ion chelating activities were determined. L. plantarum KCTC 3099 presented little SOD activity, but had the higher level of chelating activity for both Fe2+ and Cu2+ metal ions at 13.6 ppm and 23.9 ppm, respectively. These results suggested that the antioxidative capacity of L. plantarum KCTC 3099 is apparently caused by chelating metal ions rather than by SOD activation.