实验性脑积水分流后脑顺应性的改变

目的：用梗阻性脑积水犬模型，观察脑积水分流前、后及阻断分流后脑顺应性的变化。方法：随机将成年健康杂种犬18只分为2组。实验组(12只)，向四脑室注入氰基丙烯酸凝胶诱导脑积水，诱导术后第8周，测量实验犬颅内压及其低压（5～15?mmHg）、高压（15～25?mmHg）时的脑顺应性，随后对脑积水犬进行脑室-腹腔分流手术；第10周再次测量分流后的颅内压和脑顺应性，并阻断分流管；第11周做颅内压和脑顺应性的最后测量。实验前和每次测量前，犬进行磁共振成像（MRI）检查。对照组(6只)，仅注入等量的生理盐水。结果：实验组MRI证实有10只犬形成脑积水。分流前的颅内压实验组（9.98±1.84）mmHg明显高于对照组（3.82±1.19）mmHg，P<0.01；分流后颅内压恢复正常（4.28±1.25）mmHg，P>0.05，阻断分流管后很快恢复到分流前状态。高压时的脑顺应性在脑积水分流前、后和阻断分流后3个阶段是逐渐降低的［（0.065±0.008） ml/mmHg，（0.053±0.013） ml/mmHg，（0.032±0.005） ml/mmHg，P<0.05］。结论：犬梗阻性脑积水模型很适合脑积水的病理生理和治疗研究，脑顺应性下降可能是脑积水分流失败后呈急性恶化发病的机制之一。     

同种异基因大鼠子宫移植细胞因子表达的研究

目的研究大鼠子宫移植中γ干扰素(IFNγ)、转化生长因子β1(TGFβ1)和白细胞介素-10(IL-10)的表达及其与排斥反应的关系。方法建立大鼠(SD→W istar)子宫异位移植模型,分为正常子宫对照组、同基因子宫移植组和异基因子宫移植组。各组大鼠分别于术后第2~6天切取移植物进行病理学检查、实时荧光定量PCR检测细胞因子mRNA表达。结果移植后第3天,异基因组组织病理表现出排斥反应并进行性加重;同基因组移植子宫无排斥现象;与对照组相比,同基因组中3种细胞因子mRNA表达均无明显差异(P>0.05);与对照组和同基因组相比,异基因组中除TGFβ1移植后第3天表达无明显差异(P>0.05),其余细胞因子均明显升高(P<0.01)。3种细胞因子表达于移植后第4或第5天达到高峰(P<0.01);IFNγ升高幅度为IL-10的4倍,TGFβ1的16倍。结论细胞因子IFNγ、TGFβ1、IL-10在SD→W istar大鼠子宫移植的急性排斥反应中有一定作用,其中以IFNγ的作用最为明显。     

Acute-onset nontraumatic paraplegia in childhood: fibrocartilaginous embolism or acute myelitis?

Fibrocartilaginous embolus causing acute spinal cord infarction is a rare cause of acute-onset paraplegia or quadriplegia. Few cases of survivors have been reported in the neurosurgical literature, with most reports involving post-mortem or biopsy findings. There is little information on MRI findings in such patients. We present the youngest patient ever reported, and discuss the important differences between fibrocartilaginous embolus and acute myelitis of childhood. A 6-year-old girl with a history of back pain presented with sudden-onset nontraumatic paraplegia, with a clinical anterior spinal artery syndrome. Initial MRI scan revealed intervertebral disc disease at L1–2 and an incidental thoracic syrinx, but no cause for her acute-onset paraplegia was identified. Cerebrospinal fluid and other investigations were all negative. Sequential MRI scans revealed development of spinal cord expansion from T10 to the conus medullaris, with increased cord signal in the anterior aspect of the spinal cord. The intervertebral disc disease was unchanged. The imaging and clinical findings were caused by fibrocartilaginous embolus, which meant there was no need for spinal cord biopsy. The report describes the clinical and imaging criteria for diagnosis of fibrocartilaginous embolus, highlighting the case for avoiding an unnecessary biopsy. The clinical pattern in the paediatric group is discussed, with features differentiating it from acute myelitis of childhood. Received: 4 January 2000     

白背叶根抗鸭乙型肝炎病毒的实验研究

目的:观察白背叶根体内抗鸭乙型肝炎病毒(duck hepatitis B virus,D-HBV)的作用。方法:采用PCR技术筛选D-HBV阳性3日龄广州麻鸭40只。将麻鸭随机分为空白对照组,白背叶根高、中、低剂量组和拉米夫定组,分别给予相应药物进行干预。用药前、用药第7、14、21天及停药第7天,取各组麻鸭静脉血,采用实时定量荧光PCR技术检测血清D-HBV DNA含量;治疗前后取肝脏组织进行病理组织学观察。结果:拉米夫定组于用药后,血清病毒水平迅速降低,但停药后存在反跳现象。白背叶根高、中剂量组分别于治疗第14、21天其血清病毒含量明显下降,低剂量组治疗期间未见明显的抑制病毒作用。停药后,白背叶根高、中剂量组与空白对照组比较仍表现出一定的病毒抑制作用。白背叶根高剂量组对肝脏炎症的改善作用较拉米夫定组明显。结论:白背叶根有抑制体内D-HBV复制的作用,其作用大小与剂量及用药时间相关;其治疗作用较拉米夫定弱,但作用维持时间长,且用药较为安全。     

MRI用于立体定向放射治疗定位的精确性分析

目的：研究MRI用于立体定向放射治疗（SRT）定位时误差的大小，明确MRI能否单独用于SRT定位。方法：模拟对病人的扫描方法，对特制体模进行固定和MRI扫描。在治疗计划系统上，测量x、y、z3个方向靶点距离，并将结果与实际距离做比较，差别的绝对值即为该定位系统的误差。结果：相邻点x方向，误差0.2～1.4mm，平均0．9mm；y方向误差0.5～1.5mm，平均0．9mm。相对点x方向，误差0.3～1．7mm，平均0.9mm；y方向，误差0.4～1．8mm，平均0．9mm。各标记层面之间误差无显著性差别（P〉0．05）。z方向误差0．3～1.9mm，平均1．0mm。结论：本研究采用的立体定向定位系统和MRI扫描方法，用MRI进行影像采集制定SRT计划，对多数颅内和头颈部肿瘤的定位精度符合临床要求，但在将MRI进行SRT定位扫描时，必须作全面的检查和验证。     

Effects of tetrandrine on phenotypic modulation of vascular smooth muscle cells and expression of p38 MAPK as well as MKP-1 after intimal injury of rabbit carotid arteries

Objective： To study the effects of tetrandrine （Tet） on phenotypic modulation of vascular smooth muscle cells （VSMCs） and expression of p38 mitogen-activated protein kinase （p38MAPK） as well as mitogen-activated protein kinase phosphatase-1 （MKP-1） after vascular intimal injury. Methods： HE staining was used to analyze vascular morphology of sham-injured group, injured group and Tet-treated group at day 28. lmmunohistochemistry, Western blot and RT-PCR were respectively used to detect the expression change of smooth muscle a-actin （SMa-actin）, proliferation cell nuclear antigen （PCNA）, p38MAPK and MKP-1 of injured group and Tet group at days 7, 14 and 28 after balloon injury. Results： ① All layers of vascular wall in sham-injured group were intact at day 28. The neointimal area was significantly increased and the lumen area notably decreased in injured group at day 28. The neointimal proliferation in Tet treated group was less than that in injured group, and the lumen area of Tet group was significantly increased than that of injured group at day 28. ②Compared with the injured group, the expression of SMa-actin, PCNA, p38MAPK and MKP-1 of vascular wall in Tet group was no difference, and the neointimal proliferation condition was also basically as same as injured group at day 7 after injury. The expression of PCNA and p38MAKP in Tet group was obviously lower than that in injured group, and the expression of MKP-1 in Tet group was obviously higher than that in injured group at days 14 and 28 after injury. The expression of SMa-actin in Tet group was slightly higher than that in injured group at days 14 and 28 after injury. Conclusions： Tet could reduce neointimal proliferation by inhibiting VSMCs phenotypic modulation and p38MAPK signaling transduction pathway as well as its down regulation.     

三日龄大鼠缺氧缺血性脑损伤对大脑MRI影像和学习记忆能力的远期影响

Objective To investigate the activation of apoptotic genes of the brain with hypoxia- ischemia (HI) in newborn SD rats, and MRI changes and memory and learning ability in adulthood. Methods HI was induced by right carotid artery ligation followed by 2.5 h of hypoxia (6% O2) on 3-day-old SD rats (n=36). Control pups were sham-operated (n = 27). Right brain hemisphere was collected at 12 h and 7 d after HI and subjected to an apoptosis Oligo GEArrayR. MRI and Morris water maze test were performed on both groups at 42 and 44 days old, respectively. Results Comparing to 12 h after HI, up-regulated apoptotic genes included TNF, Caspase and pro-apoptotit genes of Bcl2 families, whereas the anti-apoptotic genes of Bcl2 family were down-regulated at 7 d after HI. The MRI assessment of the rats in HI group demonstrated that the area of the right cerebra l cortex was significantly smaller than the left side and control [periventricular layer: (23.5±3.6) mm2 vs (33.0±4.3) mm2, (34.5±3.9) mm2; hippocampus layer: (18.9±4.4) mm2 vs (29.1±5.0) mm2,(30.8±4.5) mm2, both P<0.01]. During the navigation trial, the HI rats demonstrated longer escape latency (4th day: (52.7±35.9) vs (17.8±8. 9) s, P<0.01). HI rats passed the platform less times than the control ones (T= 292.5, P<0.05) in space probe trial. Conclusions The activation of apoptotic genes induced by HI brain injury remains until 7 days later, involving intrinsic and extrinsic apoptotic pathway. The apoptosis of neural cells may lead to poor development of the cortex and impair the memory and learning ability in the adult rats after neonatal hypoxia- ischemia injury.     

地塞米松对急性淋巴细胞白血病患儿核转录因子-κB表达的影响及意义

目的探讨儿童急性淋巴细胞白血病(ALL)核转录因子-κB(NF-κB)p65蛋白的表达及意义,观察地塞米松(DEX)对其活性的影响,为临床寻求以NF-κB为靶点的治疗手段的依据。方法1.应用SP免疫组化法,检测20例ALL患儿和20例正常对照儿童NF-κB p65蛋白表达。2.用SP免疫组化法检测DEX对ALL细胞NF-κB p65蛋白活性影响。结果1.ALL患儿20例的NF-κB p65蛋白阳性表达率为85.50%(17/20),表达定位于ALL细胞胞核及胞浆中,明显高于正常对照组10.0%(2/20),两者比较有显著性差异(χ2=22.56 P<0.01)。2.临床治疗剂量的DEX 5.0 mg/L作用于ALL细胞24 h,能显著抑制NF-κB p65蛋白表达,其阳性表达率为(25.0±3.0)%,与未处理的ALL细胞比较,有显著性差异(t=55.00 P<0.01)。结论1.NF-κB p65蛋白表达于儿童ALL细胞中。2.抑制NF-κB的活性可能是DEX作用于儿童ALL细胞的机制之一,抑制NF-κB信号传导途径可能在儿童ALL治疗中有重大价值。     

磁共振弥散加权成像在病毒性脑炎诊断中的应用

目的探讨磁共振弥散加权成像(DWI)在病毒性脑炎诊断中的价值。方法对20例诊断病毒性脑炎患儿行常规磁共振成像(T2WI-T1WI)和DWI检查,比较3种成像的异常率和发现的病变部位。结果DWI异常率明显高于T1WI(χ2=4.44 P<0.05),而DWI和T2WI的异常率无明显差异(χ2=1.20 P>0.05)。12例病后1周内同时作T1WI、T2WI和DWI检查,5例T1WI和2例T2WI正常者DWI均显示异常;2例T2WI与DWI发现的病灶部位数相同,8例DWI发现的病灶部位数多于T1WI和T2WI。5例于发病1周后同时作T1WI、T2WI和DWI检查,三者异常率相同,发现的病变部位也基本相同。14例发病10~35 d复查MRI,多数未能恢复正常。结论DWI对发现病毒性脑炎急性期的病灶较T1WI或T2WI敏感,DWI在急性病毒性脑炎的诊断中具有重要价值。     

定量组织速度显像评价高血压病患者左心室舒张功能的研究

目的研究高血压病患者左室整体舒张功能变化及定量组织速度显像（QTW）估测的舒张功能参数与常规二尖瓣血流参数的相关关系。方法依照左室质量指数将高血压组患者分为左室肥厚组（LVH group，n=53）与非左室肥厚组（N—LVHgroup，n=50）。应用M型超声测量舒张期室间隔厚度（IVSd）、左室后壁厚度（LVPWd）、左室内径（LVEDD），常规脉冲多普勒测量二尖瓣舒张期E波峰速度（E）、A波峰速度（A）、计算E／A比值。利用QTVI技术测量二尖瓣环六位点舒张期早期运动速度（e）、舒张期晚期运动速度（a）、计算e／a。同时计算六位点平均速度（em、am、em／am）以及E／em，比较三组舒张功能指标的差异及各参数间的相关关系。结果高血压病LVH组及N—LVH组与正常对照组比较，多项舒张功能指标（e、a、e／a、em、am、em／am以及E／em）差异具有显著性（P〈0．05），二尖瓣环舒张期运动速度与二尖瓣多普勒血流速度相关。结论高血压病无论是否存在左室肥厚均有舒张功能损害，QTVI为定量评价高血压病左室舒张功能提供了一种新方法。