长效抗生育埋植剂CaproF体内药物释放的研究

目的对可降解长效抗生育埋植剂CaproF的体内药物释放动力学进行评价。方法将CaproF植入Wister大鼠皮下。每隔一定时间处死动物,取出埋植剂,用紫外分光光度法测药物残留量,计算单位长度埋植剂平均每日药物释放量。放射免疫法测定左炔诺孕酮(LNG)血药浓度。结果CaproF埋植剂在60、120、180、360、720d药物平均释放速率分别为(11.0±3.0)、(11.7±3.7)、(8.0±1.2)、(7.3±0.4)、(9.3±0.9)μg/(d·cm),并可维持基本恒定的血药浓度。结论左炔诺孕酮CaproF埋植剂植入体内后,平均药物释放速率达到7.6μg/(d·cm),并可维持2年的基本稳定释放。     

新型角膜支架材料的制备及生物相容性研究

首先合成了一种新型可降解的三乙烯基交联剂,并以偶氮二异丁氰(A IBN)为引发剂与乙烯基吡咯烷酮(NVP)通过自由基聚合制备了一种新型的交联NVP角膜支架材料。对材料的吸水率、接触角和降解性能进行了测定,通过体内埋植实验和细胞培养对材料进行了生物相容性评价。结果表明材料的吸水率达到104%,接触角为41,°降解速率较为恒定;体内埋植实验研究表明,3个月后,材料已大部分降解,材料内出现胶原和角膜基质细胞,周围组织无明显的炎症反应;细胞培养实验表明,角膜上皮细胞在材料上可以较好的生长,没有明显的细胞毒性,具有良好的生物相容性,这种合成的新型交联NVP角膜支架材料将在角膜组织工程中具有潜在的应用价值。     

医用聚己内酯埋植剂体内降解的研究

目的 对医用聚己内酯埋植剂材料合成及体内降解进行研究,了解埋植剂材料的性能. 方法 Pluronic F68经乙酰封端处理后与己内酯单体（CL）混合,加入催化剂于N2保护的聚合釜中,在140 ℃～170 ℃条件下聚合48 h,用挤出机制成管材.研究致孔剂的工艺、微孔的形成.用核磁共振和扫描电镜等方法观察聚己内酯埋植剂材料的结构.用氚标记的低相对分子量的聚己内酯胶囊植入大鼠皮下,测定其体内降解、吸收和排泄. 结果 含有F68的医用聚己内酯埋植剂材料（PCL/F68）在亲水介质中F68很快溶出,可形成多微孔结构.该材料起始相对分子量为66 000时,在体内可完整存在2年,2年后降解为低相对分子量碎片,可被机体吸收、排泄,不在体内积蓄. 结论 聚己内酯/F68埋植剂材料在体内可降解并主要通过粪便排出体外,不在体内积蓄,脏器中放射性极少.     

生物材料体内外试验相关性研究——细胞与软组织毒性

生物材料在医学领域已广泛应用 ,材料的安全性评价是极其重要的一环。研究生物材料体内外试验方法的相关性 ,以探求与体内动物试验相关性好的体外评价方法。采用白细胞趋化试验、流式细胞仪法、MTT比色法等体外方法与大鼠皮下埋植试验、兔肌肉埋植试验等体内方法 ,对七种生物材料的组织毒性进行了评定 ,并应用Spearman秩相关统计方法对体内和体外试验方法作对应进行相关性分析。结果表明 :体外方法均与体内方法有良好相关性。     

水溶性止血纺织材料植入兔肌肉的组织病理学研究

将６种止血纺织材料分别埋植兔脊柱两侧肉内，在埋植后７天、１４天、９０天进行了组织病理学研究。３种水溶性止血纺织材料在体内降解吸收较快，但有液化腔形成；３种水溶性止血纺织材料在体内降解吸收较慢，但在９０天也能被完全降解。Ｓ－１００系列材料相对反应较轻。     

NaOH消蚀法制备骨细胞外基质材料的实验研究

目的 :　研制一各新型的天然骨移植替代材料 ,为其临床应用提供实验依据。方法 :　采用NaOH消蚀法制作家兔骨细胞外基质支架 ,扫描电镜观察 ;对支架行生物相容性实验 ,将支架埋植于兔背部肌肉内 ,分别于术后 1周、2周、4周、6周取出行组织学观察 ,X射线能谱分析埋植前、后化学元素组成的改变。结果 :　 (1)SEM观察 ,以NaOH消蚀处理后 ,骨组织中的细胞成分被彻底清除掉 ,细胞外基质成分 -胶原纤维及骨盐则维持原有形态及三维立体网状结构。 (2 )光镜下观察 ,支架周围有成纤维细胞及毛细血管增生 ,轻度淋巴浸润 ;支架结构随埋植时间渐稀疏、紊乱。 (3)X射线能谱分析结果 ,埋植后钙原子含量低于埋植前水平 (p <0 .0 0 1)。结论 :　NaOH消蚀骨支架作为骨移植替代材料 ,其三维立体网状结构为成骨细胞发挥功能提供了有利空间 ,有可能作为骨组织工程中种子细胞的载体 ;骨盐的存在使其具有一定的力学强度 ,适宜修复较大节段的骨缺损 ;组织相容性好 ,在体内可降解吸收。     

生物材料体内外试验相关性研究——体外白细胞趋化试验与体内肌肉埋植试验的相关性探讨

探讨生物材料体内外试验的相关性。对七种生物材料分别以体外白细胞趋化性试验和体内肌肉埋植试验来评价材料的组织毒性。体外试验表明不同毒性材料对白细胞趋化能力有不同程度的影响，而导致机体对异物产生不同的抗炎反应；各期体内试验反映了材料在肌肉组织中不同的炎性反应。经Ｓｐｅａｒｍ ａｎ 秩相关统计处理，两种方法的相关系数较高（介于０．８９２８６～０．９８１９８），初步显示白细胞趋化性试验和肌肉埋植试验具较好相关性。     

聚(丙基，3-羟丙基)DL-天冬酰胺的体内外降解及键合阿司匹林复合物的释放行为的研究

选用两种不同亲疏水性的聚天冬酰胺修饰材料进行体内外降解实验,研究结果表明,聚天冬酰胺材料的降解过程系酶解,材料的亲疏水性不同,则在体内的降解速度不同,同种材料在埋植部位、肾、肝中的代谢速度也不同。对两种材料的键合阿司匹林复合物的体内外释放试验表明,酶解有利于药物的释放,材料的亲脂性增加有利于药物的释放。     

生物材料体内外试验相关性研究——：体外白细胞趋化？…

探讨生物材料体内外试验的相关性。对七种生物材料分别以体外白细胞趋化性试验和体内肌肉埋植试验来评价材料的组织毒性。体外试验表明不同毒性材料对白细胞趋化能力有不同程度的影响，而导致机体对异物产生不同的抗炎反应；各期体内试验反映了材料在肌肉组织中不同的炎性反应。经Ｓｐｅａｒｍａｎ秩相关统计处理，两种方法的相关系数较高（介于０．８９２８６～０．９８１９８），初步显示白细胞趋化性试验和肌肉埋植试验具较好相关     

聚（丙基,3—羟丙基）DL—天冬酰胺的体内外降解及键合阿司匹林 …

选用两种不同亲疏水性的聚天冬酰胺修饰材料进行体内外降解实验，研究结果表明，聚天冬酰胺材料的降解过程酶解，材料的亲疏水性不同，则在体内的降解速度不同，同种材料在埋植部位、肾、肝中的代谢速度也不同。对两种材料的键合阿司匹林复合物的体内外释放试验表明，栈解有利于药物的释放，材料的亲脂性增加有利于药物的释放。     

Secular change in menarche in women in Madrid

The age at menarche was estimated by recollection in 1617 women between the ages of 18 and 60 in Madrid and a nearby suburb, Pinto. The population of Pinto is working-class and the Madrid group, taken from residential neighbourhoods , belongs to the upper middle class. In both groups we found a diminution in average age at menarche, from 14.04 to 13.02 years in Madrid and from 14.55 to 13.16 years from about 1935 to about 1965 in Pinto. These changes have been more intense in the group which is less well-off economically, where living conditions have varied much more drastically.     

Intestinal helminthiasis in school children in Haiti in 2002

A survey on intestinal helminths in school children was conducted in Haiti in 2002. This first nationwide study involving the entire country was stratified by department according to urban and rural zones using the cluster method. Focusing on elementary school children (n=5792; age range 3 to 20 years), it involved 26 urban and 49 rural schools randomly selected. Stools were preserved in formalin and examined by the Ritchie technique. Thirty-four per cent of stools (1981/5792) tested positive for intestinal helminths with the following parasites identified: Ascaris lumbricoides (27.3%), Trichuris trichiura (7.3%), Necator americanus (3.8%), Hymenolepsis nana (2%), Taenia sp. (0.3%) and Strongyloides stercoralis (0.2%). The helminth prevalence was higher in rural (38.4%) compared to urban areas (30%). There was no significant difference in prevalence by sex and age. The importance of geohelminths changed from one department to another with the highest prevalence found in the Southern department of Grande Anse (73.7%) and the lowest prevalence in the Center department (20.6%). Five out of the country's nine departments had a similar prevalence varying from 25.5% to 28.2%. Intestinal helminthic polyparasitism was observed in a percentage of infested school children comprise between 3.4% and 28.6% according in relation to the geographical area. A program to fight against geohelminths in school children should be initiated as a public health priority. Albendazole is the drug of choice. Frequency of drug distribution should be based on the prevalence of geohelminths in each department.     

Experience in adult population in dengue outbreak in Delhi

A dengue outbreak has recently hit the Indian capital. We studied the clinical profile of adult patients. Five hundred and sixty patients of dengue infection were admitted in a specially created ward according to the criteria laid down by WHO. Haematemesis (28.28%), epistaxis (26.78%) and malena (14.28%) were some of the common presentations. Similarly lymphadenopathy, especially cervical (30.89%), palatal rashes (26.96%) and hepatomegaly (23.75%) were the most commonly encountered findings on physical examination. Most of the cases were of dengue fever with haemorrhage and only 2.5% cases were classified under dengue haemorrhagic fever or dengue shock syndrome. The average hospital stay was 3.4 days but only 9.8 hours in the eleven patients who died, suggesting their late arrival in preterminal situation giving little time for resuscitation. Thrombocytopenia was not a feature and only 12.85% patients had platelet count less than 70,000/cmm. Most of the patients who were admitted with thrombocytopenia, showed normalization in their platelet counts in next few days. Serological examination demonstrated evidence of recent dengue infection in 41.17% patients. Few patients required blood or platelet concentrate transfusion. Eleven patients died, three due to DIC, one of intracranial haemorrhage and seven due to massive gastric haemorrhage. Rest of the patients recovered completely. Thus we can conclude that recent outbreak in Delhi was of dengue fever with haemorrhage and mortality was very low in patients who came early to the hospital.     

Changes in the hypothalamic nuclei in in experimental allergy

Summary In rabbits subjected to prolonged sensitization and in which the Arthus phenomenon was induced there was a marked reaction of the hypothalamic nuclei. Staining by Gomori's method indicated a cellular swelling, loss of granules, and protoplasmic vacuolization in the supraoptic nucleus. There was a considerable increase in the size of the cross-sectional area of the cells. The same effects were much less well shown in the paraventricular nucleus. These results show that marked signs of increased neurosecretion developed in the animals at the height of the Arthus phenomenon.(Presented by Active Member AMN SSSR V. V. Parin) Translated from Byulleten Éksperimental'noi biologii i Meditsiny, Vol. 55, No. 4, pp. 110–113, April, 1963.     

Development in in vitro toxicology

There are three principal pressures driving the development of in vitro toxicology: (1) the need for more efficient testing systems to cope with the large number of xenobiotics currently being developed; (2) public pressure to reduce animal experimentation; and (3) a need for a better understanding of the mechanisms of toxicity. Within this, in vitro toxicology is focused on local, systemic, and target-organ toxicity. It is becoming increasingly apparent that a step or decision-tree approach using input of a variety of experimental data (physicochemical properties, biokinetics, cytotoxicity) provides the most efficient system for predicting toxicity. Examples of the use of in vitro toxicity systems for prediction of systemic toxicity and target-organ (liver) toxicity are presented.Originally presented at ECCP 93.