硫氧还蛋白对大鼠睾丸缺血再灌注损伤保护作用的研究

目的 探讨硫氧还蛋白对大鼠睾丸缺血再灌注损伤的保护作用.方法 选取雄性SD大鼠60只,随机分为4组:假手术对照组(A组);睾丸扭转/复位组(B组);睾丸扭转/复位+腹腔内注射生理盐水组(C组);睾丸扭转/复位+腹腔内注射硫氧还蛋白组(D组).无菌条件下制作左侧睾丸扭转模型,扭转持续4h,复位4h后取睾丸标本(D组在复位前15 min腹腔内注射硫氧还蛋白).对标本进行病理组织学检查;检测睾丸组织中超氧化物歧化酶(SOD)和丙二醛(MDA)的含量.结果 睾丸扭转/复位后可见生精小管退变,间质出现水肿及出血,腹腔注射硫氧还蛋白使睾丸扭转/复位诱发的组织学改变明显改善.B组及C组睾丸损伤评分(8.3±0.96;8±0.87)明显高于A组(0.78±0.36)(P＜0.01),而腹腔注射硫氧还蛋白可以使睾丸损伤分值(3.1±0.42)显著降低(P＜0.05).B组及C组MDA含量(4.39±0.21;4.42±0.17)升高,SOD活性(269±27.1;271±21.3)降低,与对照组(MDA:1.61±0.18;SOD:317±22.3)相比,差别具有显著性意义(P＜0.01).而腹腔注射硫氧还蛋白能有效降低MDA含量(2.03±0.03)并升高SOD活性(315±24.2)(P＜0.01).结论 本实验为硫氧还蛋白作为治疗睾丸扭转继发损害的有效物质提供了组织学及生化依据.为临床预防和治疗睾丸缺血再灌注损伤提供了理论依据.     

大鼠睾丸扭转复位及减压治疗对睾丸的影响

目的 研究睾丸扭转复位及减压治疗对睾丸的影响,为睾丸扭转的预后判断、治疗方法的选择等提供新的理论依据.方法 将30只SD雄性大鼠随机分成5组,制成睾丸扭转复位及复位+减压治疗的模型.分别设立空白对照组及实验A～D组,睾丸扭转/复位组(A组)、睾丸扭转/复位+减压治疗组(B组)喂养至术后1 d处死;睾丸扭转/复化组(C组)、睾丸扭转/复位+减压治疗组(D组)喂养至术后1个月处死.应用化学检测和组织学分析方法,观察睾丸大体标本的变化、睾丸组织内丙二醛(MDA)含量的变化及睾丸组织Johnsen's评分.结果 五组睾丸MDA分别为3.18±0.22(空白对照组)、9.54±2.05(A组)、7.92±1.38(B组)、6.67±0.61(C组)、4.30±1.81(D组),实验组术侧睾丸的MDA含量显著高于自身对侧(P<0.05).D组MDA含量比C组明显下降(P<0.05).单纯复位组的术后睾丸标本比自身对侧和减压治疗组有明显萎缩;五组Johnsen's评分分别为10±0、7.2±0.18、8.2±0.19、2.2±0.19、9.2±0.18.D组比C组明显提高(P<0.05).结论 睾丸扭转复位+减压治疗能明显减少扭转侧睾丸生殖细胞凋亡,减轻脂质过氧化程度,可能有利于睾丸组织结构与功能的恢复.     

不同时机应用促红细胞生成素对感染所致新生大鼠脑损伤的保护作用

目的 探讨促红细胞生成素(EPO)对感染致新生大鼠脑损伤保护作用的最佳应用时机及其相关机制.方法 2日龄(P2)新生SD大鼠按随机数字表法分为4组,分别为对照组(A组)、脂多糖(LPS)感染组(B组)、早期EPO干预组(C组)、晚期EPO干预组(D组).A、B、C组P2新生大鼠连续5d(P2-P6)分别腹腔注射相应药物:等容积9 g/L盐水+等容积EPO空白对照品、0.6 mg/kg LPS+等容积EPO空白对照品、0.6mg/kg LPS+5 000 IU/kg EPO;D组P2新生大鼠连续5d(P2-P6)腹腔注射0.6 mg/kg LPS,P7开始连续腹腔注射5 000 IU/kg EPO 5 d(即P7-P11).A、B2组分别于P2(腹腔注射第1次药物后6h)、P7、P12,各随机数字表法抽取10只新生大鼠取脑,以矢状缝为标志分为左右半脑,右侧脑应用酶联免疫吸附法检测脑组织EPO受体(EPOR)水平,左侧脑应用反转录-聚合酶链反应(RT-PCR)方法检测EPOR mRNA水平;A、B、C3组于P7随机数字表法选取10只新生大鼠灌注取脑,余续养,4组均于P12灌注取脑,应用免疫组织化学方法检测髓鞘碱性蛋白(MBP)、胶质纤维酸性蛋白(GFAP)及EPOR的表达,采用HE染色观察各组大鼠脑组织的病理改变.结果 1.HE染色示B组海马锥体细胞界限不清、层次紊乱,细胞数目减少,脑室扩张,周围白质有囊性软化区域形成;EPO干预组较B组病理改变减轻,早期干预组更明显.2.B组较A组EPOR蛋白及mRNA表达增加,随日龄的增加EPOR与EPOR mRNA表达有下降趋势.3.B组MBP表达(107.46±3.65)较A组(146.78±3.13)明显减少(P＜0.05),EPO干预组较B组表达增加,且C组(126.25±4.42)较D组(117.35±3.42)增加更明显(P＜0.05).4.B组GFAP表达(P7、P12分别为141.46±11.92、149.48±13.59)较A组(P7、P12分别为120.63±13.32、119.74±12.48)增加(P＜0.05),P12时EPO干预组表达较B组降低,C组(134.59±12.19)与D组(137.27±13.87)差异无统计学意义(P＞0.05).结论 EPO对出生后感染所致的脑白质损伤有保护作用,且甲期应用优于晚期,其机制可能与感染可使新生大鼠脑组织EPOR表达增加及EPOR表达随日龄增加而降低有关.     

脂多糖对不同脑成熟程度早期新生鼠髓鞘发育的影响及肿瘤坏死因子-α表达变化

目的 通过向2日龄(P2)、7日龄(P7) Wistar新生鼠腹腔注射相同剂量的脂多糖(lipopolysaccharide,LPS),采用2’,3’环核苷酸3’磷酸二酯酶(2’,3’-cyclic nucleotide phosphodiesterase,CNPase)和髓鞘碱性蛋白(myelin basic protein,MBP)分别标记未成熟少突胶质细胞和成熟少突胶质细胞,动态监测感染因素对两组新生鼠脑白质区髓鞘发育的影响,并检测这一过程中脑组织肿瘤坏死因子(tumor necrosis factor,TNF)-α表达的变化,探讨TNF-α在脑白质损伤(white matter damage,WMD)发生中的作用.方法 将96只新生Wistar大鼠随机分为4组,每组24只,A组(P2新生鼠腹腔注射LPS5.0 mg/kg),B组(P7新生鼠腹腔注射LPS 5.0 mg/kg),C1、C2组(分别向P2或P7新生鼠腹腔注射等量生理盐水).观察各组新生鼠脑组织病理变化,免疫组织化学技术测定给药后24h脑组织CNPase蛋白表达变化及日龄14d(P14)脑组织MBP蛋白表达的变化,RT-PCR法测定给药后4h脑组织中TNF-αmRNA表达的变化.结果 A组大鼠脑组织病理可见胼胝体区、外囊区灶性出血及侧脑室内出血,P14时胼胝体区可见软化灶,软化灶的周围可见胶质增生.而B组和C1、C2组脑白质区组织结构清晰,无明显的细胞增生和出血.A组脑室周围白质区阳性CNPase表达程度及面积较C1组弱(106.93±2.62vs 113.67±2.69,P＜0.01),B组染色程度及面积亦较C2组弱(96.37±1.82 vs 101.65±2.01,P＜0.01).P14时,与C1组相比,在胼胝体及放射冠区A组MBP染色明显减少(128.21±2.99 vs 134.81±2.98,P＜0.01),而B组较C2组无明显改变(134.77±3.68 vs 134.81±2.98,P＞0.05).给药后4h,A组新生鼠脑组织中TNF-α mRNA表达相对值较B组增强(1.79±0.04 vs 1.18±0.04,P＜0.01).结论 处于脑发育中的未成熟新生鼠腹腔注射LPS可对脑的髓鞘发育产生重要影响,导致髓鞘形成障碍或发育延迟,进而发生WMD,TNF-α在WMD发生时表达明显增加;而脑发育相对成熟的新生鼠则可抵御LPS的损伤,仅发生髓鞘发育的延迟而无明显的髓鞘形成障碍.     

不同日龄隐睾复位大鼠睾丸组织结构观察

目的 观察不同13龄隐睾复位大鼠睾丸组织结构的变化.方法 72只21 d雄性SD大鼠随机分为单侧隐睾组、双侧隐睾组、假手术对照组各24只.建立单、双侧隐睾动物模型.2周后行隐睾大鼠睾丸下降固定术,于日龄40、60 d处死取睾丸,采用苏木素.伊红染色光镜下观察各组大鼠精曲小管生育力指数(TFI)和平均精曲小管直径(MTD);生物素-dUTP/酶标亲和素法(TUNEL法)检测睾丸生殖细胞凋亡情况.结果 隐睾侧睾丸MTD、TFI显著低于阴囊内睾丸,而隐睾生殖细胞凋亡指数(AI)明显增高于阴囊内睾丸(P＜0.05);单侧隐睾组阴囊内睾丸TFI低于相应日龄的假手术对照组,但无统计学意义(P＞0.05).40 d时单侧隐睾组隐睾侧睾丸生殖细胞AI较双侧隐睾组低(P＜0.05),日龄60 d,各组隐睾侧睾丸AI较40 d时明显降低(P＜0.05),但单侧隐睾和双侧隐睾AI比较无统计学差异(P＞0.05).结论 实验隐睾复位大鼠睾丸AI升高,同时单侧隐睾鼠对侧睾丸组织存在不同程度的损害.随着复位时间的延长,隐睾组织的病理损害有恢复的趋势.     

内毒素诱导新生大鼠肾脏损害及地塞米松的干预作用

目的：探讨新生大鼠内毒素血症时肾脏损害的部分机制及地塞米松(Dex)的干预作用。方法：取7日 Wistar大鼠150只,随机分为A组(对照组)：等体积生理盐水腹腔注射;B组(LPS组)：内毒素(LPS)5 mg/kg腹腔注射制成内毒素血症模型;C组(治疗组)：LPS 5 mg/kg+Dex 5 mg/kg共同腹腔注射。各组于注射前(0 h)及注射后2,4,6,24 h分别断头处死留取肾脏。肾组织一氧化氮(NO)采用硝酸还原酶法测定,肾组织一氧化氮合酶(NOS)采用底物催化法测定,通过电镜观察肾脏超微结构变化。结果：①B组NO于2 h高于A组同时间点NO浓度(1.69±0.44 nmol/mg vs 1.20±0.36 nmol/mg),差异有显著性(P<0.05)。于24 h为同时间点A组的 2.3倍(3.12±0.41 nmol/mg vs 1.35±0.38 nmol/mg),差异有显著性(P<0.01);C组NO也于2 h明显高于A组同时间点NO浓度(1.63±0.27 nmol/mg vs 1.20±0.36 nmol/mg),(P<0.05),但于24 h升高程度低于B组(2.10±0.27 nmol/mg vs 3.12±0.41 nmol/mg) (P<0.05);②B组肾NOS于2 h明显高于A组同时间点NOS浓度(0.47±0.15 U/ml vs 0.38±0.12 U/ml) (P<0.05),于4 h短暂下降后于24 h明显高于同时间点A组NOS浓度(0.65±0.27 U/ml vs 0.38±0.15 U/ml) (P<0.05);C组NOS浓度自6 h逐渐升高,至24 h均明显低于B组 0.51±0.07 U/ml vs 0.65±0.27 U/ml) (P<0.05);③电镜下A组肾小球基底膜(GBM)完整,上皮细胞足突清晰,肾小管上皮细胞完整,可见刷状缘。B组6 h肾小球GBM完整,部分上皮细胞足突融合,肾小管上皮细胞线粒体空泡变性;24 h肾小球GBM断裂,上皮细胞足突明显融合,系膜细胞线粒体嵴断裂,空泡变性。肾小管上皮细胞线粒体扩张成大泡。C组24 h肾小球GBM基本正常,上皮细胞足突部分轻度融合,系膜细胞内少数线粒体空泡变性,肾小管可见刷状缘。 结论：新生鼠内毒素血症时肾脏NOS产生增加,诱导合成过量的NO参与肾损伤。Dex通过调节肾脏NOS而抑制NO的大量合成,具有肾脏保护作用。     

单侧隐睾大鼠对侧睾丸组织中SCF/c-kit基因表达变化及意义

目的 研究单侧隐睾大鼠对侧睾丸病理变化及SCF/c-kit基因表达,探讨单侧隐睾致对侧睾丸损害的机制.方法 30只SD大鼠随机分为对照组和实验组,实验组复制单侧(左侧)腹腔隐睾模型.3个月后分别取两组右侧睾丸组织进行real-time RT-PCR、Western blot及免疫组化检测干细胞生长因子(SCF)和其受体c-kit基因及其蛋白表达变化,TUNEL法检测细胞凋亡.结果 所有动物均存活,与对照组相比实验组对侧睾丸明显缩小,光镜下观察其曲细精管发生退化,生精上皮变薄,管腔较空,生殖细胞明显减少,细胞凋亡增加.两组凋亡指数分别为14.4±0.63和4.45±0.37,差异有统计学意义(P＜0.05).荧光实时定量PT-PCR检测SCF、c-kit基因mRNA含量,实验组对侧睾丸明显降低,两组相比差异有统计学意义(P＜0.05).Western blot检测SCF及c-kit蛋白表达含量,实验组对侧睾丸同样明显降低,两组相比差异有统计学意义(P＜0.05).免疫组化染色显示各级生精细胞膜均有c-kit表达,SCF主要表达于支持细胞膜表面,但实验组两者的表达均较对照组减弱.相关性检验SCF与AI相关系数r=-0.941,P＜0.01;c-kit与AI相关系数r=-0.908,P＜0.01;SCF与c-kit相关系数r=0.956,P＜0.01,均有统计学意义.结论 单侧隐睾可致对侧睾丸SCF/c-kit基因表达减弱,生精细胞凋亡增加引起不育.     

头皮位点药物注射对宫内感染早产鼠脑髓鞘碱性蛋白、胶质纤维酸性蛋白及神经行为学的影响

目的 探讨头皮位点药物注射对宫内感染早产鼠脑组织髓鞘碱性蛋白(MBP)、胶质纤维酸性蛋白(GFAP)的表达及神经行为学的影响.方法 37只Wistar母鼠于孕16d、17d腹腔内注射脂多糖(LPS)或相同剂量的9g·L-1盐水,将LPS组母鼠早产仔鼠(＜孕22d)于出生第7天分别予头皮位点注射VitB1、VitB12(A组)或丰富的环境干预(B组)或不做干预(C组);各组仔鼠于出生7d、25d采用免疫组织化学测脑组织MBP、GFAP蛋白的表达,并进行神经行为学检测.结果 7日龄LPS组早产仔鼠脑组织MBP蛋白表达(112.00±9.27)明显低于9g·L-1盐水组(124.26±9.40)(P＜0.01),大脑皮质及海马齿状回GFAP阳性细胞数目(39.45±4.70;22.55±3.91)明显高于9g·L-1盐水组(34.36±3.72;18.82±3.25)(Pa＜0.05);25日龄仔鼠中,脑组织MBP表达A组(138.79±9.21)高于C组(128.44±12.99)(P＜0.01),B组(141.53±13.11)高于C组(P＜0.01),GFAP阳性细胞数目大脑皮质B组(45.50±6.54)低于C组(51.42±6.99)(P＜0.01),A组(46.70±5.61)低于C组(P＜0.05),海马齿状回B组(35.35±3.70)低于C组(38.79±5.56)(P＜0.05);悬吊试验得分,A组(3.65±0.22)分、B组(3.60±0.21)分高于C组(2.70±0.21)分(Pa＜0.01);旷野试验中的得分,A组得分[(11.20±1.96)分]及B组得分[(10.80±1.96)分]均高于C组[(9.10±1.33)分](Pa＜0.01),斜坡试验中B组试验时间[(2.19±0.74)s]最短,A组所用时间[(2.30±0.71)s]明显短于C组[(3.07±0.85)s](P＜0.01).结论 宫内感染可诱发孕鼠早产并引起脑组织损伤;头皮位点药物注射可增加大鼠脑组织MBP的表达及抑制GFAP的过度表达,并改善宫内感染早产仔鼠的神经行为.     

脑钠肽对儿童毛细支气管炎并发心力衰竭的诊断价值

目的 探讨呼吸道合胞病毒(RSV)感染致儿童毛细支气管炎并发充血性心力衰竭(心衰)时血浆脑钠钛(BNP)浓度的变化与急性心衰发生的相关性.方法 选择我院2008年1月至2010年12月收治的7 d～26个月RSV感染致毛细支气管炎并发心衰患儿18例(A组),RSV感染致毛细支气管炎未并发心衰患儿20例(B组),健康儿童20例(C组),检测血浆BNP水平,同时测定其左心室射血分数(LVEF)及左室内径缩短率(FS).结果 A组患儿BNP水平为(727±153)pg/ml,明显高于B组[(37±13)pg/ml]及C组[(21±17)pg/ml](P＜0.05),LVEF及FS值明显低于B组及C组(P＜0.05).B组和C组BNP水平比较差异无统计学意义(P＞0.05).结论 BNP可作为早期诊断RSV感染所致毛细支气管炎并发心衰的指标.     

不同剂量促红细胞生成素对新生大鼠高氧肺损伤血管保护作用的研究

目的　探讨不同剂量重组人促红细胞生成素(recombinant humanerythropoietin,rhEPO)作为血管生长样因子对新生大鼠高氧肺损伤的血管保护作用.方法 新生Sprague-Dawley大鼠60只,分为空气组、高氧组(持续吸入95％的高浓度氧)、高氧+大剂量rhEPO组(于高氧暴露前1h及暴露3d后,腹腔注射rhEPO5000 U/kg)及高氧+小剂量rhEPO组(时间点同前,腹腔注射rhEPO800 U/kg),每组15只.而空气组和高氧组分别于同一时间点腹腔注射等量生理盐水.高氧暴露6d时,观察各组大鼠存活率变化,免疫组织化学法检测肺组织血管内皮标志CD31及肺血管内皮细胞生长因子(Vascular endothelial growth factor,VEGF)表达的变化.结果 高氧暴露6d后,与高氧组相比,高氧+大剂量rhEPO组大鼠存活率显著提高[86.7％ (13/15) vs 60.0％(9/15)];肺组织CD31阳性面积比[(38.69±1.69)％ vs (33.57±4.12)％,P＜0.05]和VEGF的表达(124.4296±7.282 3 vs 114.205 9±8.345 7,P＜0.05)明显增高;而高氧+小剂量rhEPO组肺组织CD31阳性面积比[(36.34±1.89)％]及VEGF的表达(115.4296±6.7199)无明显改善,差异无统计学意义(P＞0.05).结论 大剂量rhEPO(5000 U/kg)可以促进肺血管的发育和修复,对新生鼠高氧肺损伤有血管保护作用,而800 U/kg rhEPO无明显的高氧肺损伤血管保护作用.     

Allergic factors associated with the development of asthma and the influence of cetirizine in a double-blind, randomised, placebo-controlled trial: First results of ETA®

There is a common progression known as the allergic march from atopic dermatitis to allergic asthma. Cetirizine has several antiallergic properties that suggest a potential effect on the development of airway inflammation and asthma in infants with atopic dermatitis. Methods. Over a two year period, 817 infants aged one to two years who suffered from atopic dermatitis and with a history of atopic disease in a parent or sibling were included in the ETAC^® (Early Treatment of the Atopic Child) trial, a multi-country, double-blind, randomised, placebo-controlled trial. The infants were treated for 18 months with either cetirizine (0.25mg/ kg b.i.d.) or placebo. The number of infants who developed asthma was compared between the two groups. Clinical and biological assessments including analysis of total and specific IgE antibodies were performed. Results. In the placebo group, the relative risk (RR) for developing asthma was elevated in patients with a raised level of total IgE (≥ 30 kU/I) or specific IgE (≥ 0.35 kUA/I) for grass pollen, house dust mite or cat dander (RR between 1.4 and 1.7). Compared to placebo, cetirizine significantly reduced the incidence of asthma for patients sensitised to grass pollen (RR = 0.5) or to house dust mite (RR = 0.6). However, in the population that included all infants with normal and elevated total or specific IgE (intention-to-treat - ITT), there was no difference between the numbers of infants developing asthma while receiving cetirizine or placebo. The adverse events profile was similar in the two treatment groups. Discussion. Raised total IgE level and raised specific IgE levels to grass pollen, house dust mite or cat dander were predictive of subsequent asthma. Cetirizine halved the number of patients developing asthma in the subgroups sensitised to grass pollen or house dust mite (i.e. 20% of the study population). In view of the proven safety of the drug, we propose this treatment as a primary pharmacological intervention strategy to prevent the development of asthma in specifically sensitised infants with atopic dermatitis.     

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孤独症谱系障碍(autistic-spectrum disorders,ASDs)近年来患病率逐年攀升至1%左右,其症状往往伴随终生,成为严重威胁儿童健康和发展的神经发育性疾患;注意缺陷多动障碍(attention deficit hyperactivity disorder,ADHD)是儿童期最常见的精神障碍,国内报道患病率为4.13%～5.83%,其症状可延续至青少年期,甚至到成年期[1]。这两类精神障碍在成年期的临床表现、共患病、治疗策略和预后与儿童期有哪些不同呢?本文通过回顾相     

EXCITING NEW TREATMENT APPROACHES FOR PATHYPHYSIOLOGIC MECHANISMS OF SICKLE CELL DISEASE

During the past several decades, our understanding of the complex pathophysiology of vasoocclusion associated with sickle cell disease has improved greatly. Interaction of genes, hemoglobin molecules, red cell membrane and metabolic changes, cell-cell interactions and cell-plasma interactions, red cell adhesion to vascular endothelium, activation of coagulation, and vascular reactivity play a role in vaso occlusion. Penicillin prophylaxis of pneumococcal infections and appropriate use of blood transfusions and other supportive measures improved survival of sickle cell patients. Hydroxyurea made a major impact on sickle cell therapy when it was shown to decrease acute painful episodes, acute chest syndrome, and the need for blood transfusion in adults. Significant experience in the use of hydroxyurea has been accumulated in older children. The benefits and risks of hydroxyurea for younger children and long-term risks in all patients will be evaluated in future investigations. Other promising therapies include butyrate compounds, clotrimazole, magnesium supplementation, poloxamer 188, antiadhesion agents, anticoagulant approaches, and nitric oxide. Hemopoietic transplantation remains the only curative therapy. However, several transgenic mouse models are available for studies of gene therapy or other treatment approaches on biochemical, cellular, and pathologic effects of mutant genes.     

Infiltrations of Epstein-Barr virus-carrying cells in granular lymphocyte-proliferative disorders corresponding to chronic active Epstein-Barr virus infection

A 21-year-old man with granular lymphocyte-proliferative disorders (GLPD) associated with chronic active Epstein-Barr virus (EBV) infection is described. Chromosomal analyses revealed several clonal abnormalities and two of them were mainly repetitious. High copy numbers of monoclonal EBV genome were also detected in the proliferative large granular lymphocytes (LGLs), indicating the monoclonal expansion of EBV-infected LGLs. The patient had an indolent course for several years, and there was no evidence of infiltrations of his bone marrow until the end stage. At autopsy, microscopic studies revealed marked infiltrations of LGL in the liver and spleen, and the infiltrating cells were NK-cell immunophenotype. The infiltrated LGLs showed latency I.     

LUTEINIZING HORMONE RECEPTOR MUTATIONS IN DISORDERS OF SEXUAL DEVELOPMENT AND CANCER

Human male sexual development is regulated by chorionic gonadotropin (CG) and luteinizing hormone (LH). Aberrant sexual development caused by both activating and inactivating mutations of the human luteinizing hormone receptor (LHR) have been described. All known activating mutations of the LHR are missense mutations caused by single base substitution. The most common activating mutation is the replacement of Asp-578 by Gly due to the substitution of A by G at nucleotide position 1733. All activating mutations are present in exon 11 which encodes the transmembrane domain of the receptor. Constitutive activity of the LHR causes LH releasing hormone-independent precocious puberty in boys and the autosomal dominant disorder familial male-limited precocious puberty (FMPP). Both germline and somatic activating mutations of the LHR have been found in patients with testicular tumors. Activating mutations have no effect on females. The molecular genetics of the inactivating mutations of the LHR are more variable and include single base substitution, partial gene deletion, and insertion. These mutations are not localized and are present in both the extracellular and transmembrane domain of the receptor. Inactivation of the LHR gives rise to the autosomal recessive disorder Leydig cell hypoplasia (LCH) and male hypogonadism or male pseudohermaphroditism. Severity of the clinical phenotype in LCH patients correlates with the amount of residual activity of the mutated receptor. Females are less affected by inactivating mutation of the LHR. Symptoms caused by homozygous inactivating mutation of the LHR include polycystic ovaries and primary amenorrhea.     

Resurgence of measles in Singapore: profile of hospital cases

OBJECTIVE: To ascertain the profile of cases of measles seen at a general hospital during a recent outbreak that occurred despite a measles vaccination program. METHODOLOGY: A retrospective study from January 1991 to March 1998. All patients with measles (ICD code 055. 9) seen at the emergency unit or as inpatients were included. RESULTS: There were 87 cases identified. The diagnosis was clinical in all and proven serologically in 71%. Eighty-five per cent of the cases occurred between January 1997 and March 1998. There was a bi-modal age distribution with peaks in the very young (相似文献   

Personality profiles and heart rate variability (vagal tone) in children with recurrent abdominal pain

The aim of the study was to explore psychological factors and autonomic activity in children with recurrent abdominal pain and to compare them with those in a control group of healthy children. The Personality Inventory for Children was used for assessment of developmental, emotional and psychosocial factors in 25 children with recurrent abdominal pain (age, 7-15 y). Parasympathetic and sympathetic functions in these children and in 23 healthy control subjects (age, 7-13 y) were also investigated, non-invasively using a computerized polygraph. Vagal tone (parasympathetic function) was indexed by calculation of respiratory sinus arrhythmia in beats/min. Skin conductance (sympathetic function) was recorded by the constant current method. On the Personality Inventory for Children, 16 patients had high scores on somatic concern. Several patients had scores in the clinical range for depression, withdrawal and anxiety, but the mean scores for these personality profile scales were well within the normal range of healthy children. Interestingly, there was a spike on the L (Lie)-scale for most of the patients and 15 patients had scores above or close to the clinical cut-off value. As compared with the scores in healthy children, vagal tone and sympathetic tone were normal. Conclusion: Many children with recurrent abdominal pain have scores in the clinical range for depression, withdrawal, anxiety and L-scale indicating coping problems, denial and a trend towards somatic concern that may contribute to the evolution of abdominal pain. Autonomic nerve activity was not disturbed in these children.     

Overcoming surfactant inhibition with polymers

Inhibition of the function of pulmonary surfactant in the alveolar space is an important element of the pathophysiology of many lung diseases, including meconium aspiration syndrome, pneumonia and acute respiratory distress syndrome. The known mechanisms by which surfactant dysfunction occurs are (a) competitive inhibition of phospholipid entry into the surface monolayer (e.g. by plasma proteins), and (b) infiltration and destabilization of the surface film by extraneous lipids (e.g. meconium-derived free fatty acids). Recent data suggest that addition of non-ionic polymers such as dextran and polyethylene glycol to surfactant mixtures may significantly improve resistance to inhibition. Polymers have been found to neutralize the effects of several different inhibitors, and can produce near-complete restoration of surfactant function. The anti-inhibitory properties of polymers, and their possible role as an adjunct to surfactant therapy, deserve further exploration.     

Understanding infant formula

The World Health organisation recommends breast feeding infants for the first six months of life. When this breast feeding does not occur either through parental choice or medical need, infant formulas will be required. There is a bewildering array of formulas on the UK market for many different requirements. When faced with an unsettled infant many parents (and healthcare professionals) will experiment with the infant formula available and then attend the paediatric clinic looking for help and advice. It is therefore essential that paediatricians understand what milks are available and what the key differences between different products are. This review attempts to provide a simple guide through many of the formulations currently available in the UK; and offers advice for the dietary management of the child with extra calorie requirements, infants with cow's milk protein allergy, gastro oesophageal reflux disease, apparent unresolved hunger and infantile colic. Whatever the underlying condition, there is likely to be an infant formula that is suitable in this generation of ever expanding formulations.