卵清白蛋白特异性T细胞免疫诱导BALB/c小鼠的调节性免疫应答

目的：研究T细胞免疫后正常小鼠的调节性免疫应答，方法：应用体外扩增的卵清白蛋白（OVA）特异的T细胞克隆免疫BALB／c小鼠，3H－TdR掺入法分析细胞增殖，3H－TdR标记靶细胞检测杀伤T细胞的杀伤效应，间接免疫荧光法分析血清中抗T细胞抗体水平。结果：T细胞免疫后能诱导BALB/c小鼠产生调节性T细胞的增殖反应，对靶细胞的杀伤效应以及针对于活化的T细胞的体液免疫应答，并进一步降低机体对OVA抗原的应答，结论：T细胞免疫能诱导正常机体的调节性免疫应答。     

Pre-S_2、抗Pre-S_2和HBV DNA在乙型肝炎患者中的相关性分析

目的 :探讨Pre_S2 、抗Pre_S2 二对半和HBVDNA对乙型肝炎患者血清学的诊断意义。方法 :用ELISA法和PCR法分别检测 93例乙型肝炎患者和 2 8例健康人血清中的Pre_S2 ,抗Pre_S2 ,二对半和HBVDNA水平。结果 :93例乙肝患者HBsAg、HBeAg、HBcAb阳性 32例 ,HBsAg、HBeAb、HBcAb阳性 39例 ,HBsAg、HBcAb阳性 18例 ,HBcAb阳性 4例。Pre_S2 结果阳性率 6 6 .7% (6 2 / 93) ,Pre_S2 抗体结果阳性率 1.1% (1/ 93) ,HBVDNA结果阳性率40 .9% (38/ 93)。 2 8例健康人二对半 ,五项全阴 16例 ,HBsAb阳性 12例 ,Pre_S2 阳性 1例 ,HBVDNA阳性 1例 ,Pre_S2 抗体阳性 5例占HBsAb阳性 41.7% (5 / 12 ) ,Pre_S2 和HBVDNA相比有明显差异 (P <0 .0 1) ,非HBeAg阳性组中HBVDNA阳性率约低于Pre_S2 。结论 :Pre_S2 ,抗Pre_S2 ,HBVDNA和二对半在乙型肝炎血清学诊断中显示 ,Pre_S2 优于HBVDNA和二对半。Pre_S2 抗体出现早于抗HBs和抗HBe ,抗Pre_S2 阳性检出率较低 ,可能同乙型肝炎疫苗中抗Pre_S2 含量低有关。     

Acoustic startle response is disrupted in iron-deficient rats

Diurnal effects on motor control are evident in the human disease of Restless Leg Syndrome (RLS), which is purported to be linked to brain iron deficiency as well as alterations in dopaminergic systems. Thus, we explored the relationship between daily rhythms, the onset of motor dysregulation and brain iron deficiency in an animal model of iron deficiency. Male and female weanling Sprague-Dawley rats consuming control (CN) or iron-deficient (ID) diets were examined weekly for acoustic startle response (ASR) and prepulse inhibition (PPI) for a 5-week period. Iron deficiency reduced the magnitude, but not timing, of the ASR at specific time points. ASR was elevated 60% at the onset of the dark cycle relative to the median of the light cycle in male CN and ID rats. The respective elevation was 400% and 150% in female CN and ID rats during the first 2 weeks of testing. The diurnal cycle of ASR response was attenuated by 3 weeks of testing in both dietary treatment groups. PPI was not affected by iron deficiency, sex, diurnal cycle or the interaction between these factors. These results thus demonstrate that iron deficiency moderately alters ASR signaling although the inhibitory pathways of ASR do not appear to be affected.     

Reconstructing contiguous regions of an ancestral genome

This article analyzes mammalian genome rearrangements at higher resolution than has been published to date. We identify 3171 intervals, covering approximately 92% of the human genome, within which we find no rearrangements larger than 50 kilobases (kb) in the lineages leading to human, mouse, rat, and dog from their most recent common ancestor. Combining intervals that are adjacent in all contemporary species produces 1338 segments that may contain large insertions or deletions but that are free of chromosome fissions or fusions as well as inversions or translocations >50 kb in length. We describe a new method for predicting the ancestral order and orientation of those intervals from their observed adjacencies in modern species. We combine the results from this method with data from chromosome painting experiments to produce a map of an early mammalian genome that accounts for 96.8% of the available human genome sequence data. The precision is further increased by mapping inversions as small as 31 bp. Analysis of the predicted evolutionary breakpoints in the human lineage confirms certain published observations but disagrees with others. Although only a few mammalian genomes are currently sequenced to high precision, our theoretical analyses and computer simulations indicate that our results are reasonably accurate and that they will become highly accurate in the foreseeable future. Our methods were developed as part of a project to reconstruct the genome sequence of the last ancestor of human, dogs, and most other placental mammals.     

血卟啉衍生物光动力效应对体外培养人鼻咽癌细胞株的杀伤作用

目的:通过探讨血卟啉衍生物光动力学效应对人鼻咽癌细胞株CNE2的生物作用,为光动力治疗放、化疗效果较差的鼻咽癌提供理论依据。方法:实验于2005-10/2006-06在南方医科大学南方医院肿瘤生物治疗中心实验室完成。对体外培养的人鼻咽癌细胞株CNE2分为光处理和无光处理各8个实验组及各分别设对照组和空白对照组,实验组分别加入0.5,1.0,1.5,2.0,2.5,3.0,3.5,4.0mg/L血卟啉衍生物100μL,每组设7个复孔;孵育4h,对照组除不加光敏剂外其他与实验组相同,空白对照组只加培养基不加细胞和光敏剂。光处理实验组给予波长为630nm的半导体激光进行照射,照射的功率密度为20mW/cm2,照射能量密度分别为20,10,5,2J/cm2,继续孵育24h,用四唑盐(MTT)比色法测定细胞存活率。细胞存活率(%)=(实验组A值-空白对照组A值)/(对照组A值-空白对照组A值)×100%。每次实验重复3次,取平均值。结果:①血卟啉衍生物与CNE2细胞共同孵育后,采用630nm的半导体激光照射可对其产生杀伤作用,杀伤作用大小与血卟啉衍生物的浓度和激光剂量成正相关(P<0.01),但血卟啉衍生物浓度达2.5mg/L以上时杀伤细胞作用无显著增加。激光能量为20J/cm2,血卟啉衍生物的浓度为2.5mg/L时,其杀伤CNE2细胞的作用最明显。②在加入血卟啉衍生物而无激发光的情况下,血卟啉衍生物对鼻咽癌细胞生存不产生明显影响(P>0.05)。结论:血卟啉衍生物介导的光动力在体外可以对CNE2细胞产生杀伤效应,在一定范围内杀伤作用大小与血卟啉衍生物的浓度和激光剂量成正相关。     

Bedwetting and behavioural and/or emotional problems

Objective: To assess the link between enuresis nocturna and the severity of behavioural and/or emotional problems in Dutch children and the course of these problems. Setting: West-Mine Region in the Netherlands. Subjects and methods: Prospective cohort study involving 66 of the 80 bedwetting children from all 1652 children born in 1983 in this region. After 1 y, contact was still possible with 64 of the enuretics. We used the Dutch version of the Child Behaviour Checklist (CBCL) and a questionnaire about bedwetting. Results: The mean T-score for Total Problems (CBCL score) in 1992 (M1; mean age 8. 6) was 52. 1, and 1 y later was 49. 2 (M2). There was no significant difference in the CBCL scores for Ml, M2 and a matching group from the Dutch CBCL norm population, either in the group who remained wet or in the group who became dry. There were no differences between the sexes. There was no link between the severity of behavioural and emotional problems and the frequency of bedwetting. However, more children with bedwetting than expected were in the clinical range. Conclusion: There was no difference in behavioural and/or emotional problems between the first and the second measurement and the matching group from the CBCL norm group. There were no differences in behavioural and/or emotional problems between primary and secondary bedwetters, nor were there any consequences related to the frequency of bedwetting.     

The effect of changes in dietary fat on the food group and nutrient intake of 4- to 10-year-old children

OBJECTIVE: To determine how young children changed their overall diet when they changed their fat intake after 3 months of participating in a nutrition education demonstration study designed to lower low-density lipoprotein cholesterol and cardiovascular risk. METHODS: Three 24-hour dietary recalls were collected from 303 4- to 10-year-old children at baseline and 3 months later. At both times, mean number of servings from food groups, grams of fat contributed from food groups, and intake of calories and nutrients were calculated and compared among quartiles of children formed according to change in their percent of calories from total fat after 3 months. RESULTS: Children who reduced their percent of calories from total fat most (ie, by an average of 8.5%) after 3 months consumed fewer servings from meats, eggs, dairy, fats/oils, and breads but tended to increase their number of servings from lower-fat foods within those food groups, particularly from dairy foods. These children also increased their mean intake of fruits, vegetables, and desserts, and maintained average intakes of all nutrients (except vitamin D) in excess of two thirds of the respective recommended dietary allowance. CONCLUSIONS: Young children who reduced their percent of calories from total fat in accordance with the current National Cholesterol Education Program recommendations accomplished this by reducing their overall intake of higher-fat foods, replacing higher-fat foods with lower-fat foods within several food groups, particularly within the dairy group (eg, drinking skim milk instead of whole milk) and by consuming more servings of fruits, vegetables, and very-low-fat desserts. These behaviors did not compromise their mean calorie or nutrient intakes, showing that it is possible for young children to lower their fat intake safely to reduce their risk of future heart disease.     

经鼻内镜筛窦纸板进路眶内手术

目的探讨经鼻内镜筛窦纸板进路手术治疗眶内各种疾病的可行性并确立临床处理的基本原则.方法经鼻内镜进路眶内手术10例眶内异物取出术4例、球后海绵状血管瘤切除术1例、眶内侵犯或转移的恶性肿瘤切除术5例.结果眶内异物取出术3例成功,1例失败;球后海绵状血管瘤1例完整切除;鼻咽癌眶内转移1例手术切除+放射治疗后随访4年无复发,视力恢复至0.6;其他眶内恶性肿瘤4例,手术后随访1～4年均健在.10例手术后1例视力损伤,9例均保留原有视力,其中3例失明病例中2例视力有一定程度的恢复.结论位于视神经内侧的某些占位性病变可以经鼻内镜筛窦纸板进路完成.当代先进的放射治疗技术为眶内恶性肿瘤的保守性手术创造了条件.