单纯脑白质疏松症与皮质下动脉硬化性脑病的临床对比研究

目的探讨单纯脑白质疏松症(LA)和皮质下动脉硬化性脑病(BD)的临床表现、影像学及脑诱发电位的改变特征。方法(1)调查114例单纯脑白质疏松症患(LA组)和41例皮质下动脉硬化性脑病患(BD组)的发病危险因素和临床表现。(2)两组患均行CT检查，并按照脑白质异常程度分为3型。(3)LA组74例患，BD组35例患行MRI检查，根据T2WI显示的脑室周围高信号分为5型。(4)两组分别选择部分伴有高血压的患进行躯体感觉诱发电位(SEP)、脑干听觉诱发电位(BAEP)和视觉诱发电位(VEP)检查。结果(1)LA组患的危险因素呈多样化，无神经局灶体征，临床表现仅为轻度记忆力减退、步态不稳。CT显示脑白质异常以1型为主，占70．2％(80／114)；MRI脑白质异常也同样以1型为主，占71．6％(53／74)，均无脑室扩大。电生理学检查显示，SEP异常率为83．7％(36／43)，其中轻度60．5％，中度23．2％；BAEP异常率为62．8％(27／43)，潜伏期和峰间期延长；VEP异常率为53．5％(23／43)，各波潜伏期延长，均无波形消失。(2)BD组患危险因素以高血压为主(95．1％)，临床表现以神经局灶体征、明显认知功能障碍和卒中样发作为主。CT分型以3型多见，为73．2％(30／41)；MRI检查显示3型为54．3％(19／35)，4型45．7％(16／35)，41例患均有双侧脑室对称性扩大。电生理学检查显示，SEP异常率为96．7％(29／30)，其中轻度6．7％，中度46．7％，重度43．3％；BAEP异常率86．7％(26／30)，潜伏期和峰间期进一步延长，部分伴有Ⅲ、Ⅴ波缺失；VEP异常率为83．3％(25／30)，各波潜伏期进一步延长，部分P2单侧波形消失。结论单纯脑白质疏松症无特征性临床表现，诊断主要以影像学1型脑白质异常为依据；诱发电位表现为各波潜伏期延长，无波形完全缺失。皮质下动脉硬化性脑病的危险因素为高血压，临床有较明显的认知功能障碍，常见卒中样发作等特征，影像学检查CT显示3型脑白质异常，MRI显示3型或4型为诊断依据；诱发电位呈现各波潜伏期进一步延长并伴有部分波形完全缺失。     

Vascular endothelium and inflammatory process, in patients with combined Type 2 diabetes mellitus and coronary atherosclerosis: the effects of vitamin C.

AIMS: Type 2 diabetes mellitus (DM) and coronary artery disease (CAD) are both associated with endothelial dysfunction and elevated oxidative and inflammatory state. We examined the effect of vitamin C on endothelial function and levels of soluble vascular cell adhesion molecule (sVCAM-1), interleukin-6 (IL-6) and tumour necrosis factor (TNF-alpha), in DM patients with or without CAD and in non-diabetic subjects. METHODS: Thirty-seven patients with DM + CAD, 17 patients with DM without CAD and 21 non-diabetic subjects were divided into groups receiving vitamin C 2 g/day or no anti-oxidant for 4 weeks. Forearm blood flow was determined using venous occlusion gauge-strain plethysmography. Forearm vasodilatory response to reactive hyperemia was considered as index of endothelium-dependent dilation. RESULTS: Baseline levels of IL-6 and TNF-alpha were significantly higher in patients with DM + CAD compared with patients with DM (P < 0.01) or non-diabetic subjects (P < 0.01). IL-6 and TNF-alpha levels were also higher in DM compared with non-diabetic subjects (P < 0.05). sVCAM-1 levels were lower in non-diabetic controls compared with DM + CAD (P < 0.05) or DM (P < 0.05). Reactive hyperaemia was higher in non-diabetic controls compared with DM + CAD (P < 0.001) or DM (P < 0.001). Vitamin C significantly increased reactive hyperaemia only in the DM + CAD group, while it had no effect on serum levels of sVCAM-1, TNF-alpha and IL-6 in any of the groups. CONCLUSIONS: Type 2 diabetes mellitus is associated with impaired endothelial function and increased levels of TNF-alpha, IL-6 and sVCAM-1, especially in patients with DM and CAD. Vitamin C significantly increased forearm vasodilatory response to reactive hyperaemia only in patients with combined DM and CAD.     

冠心病患者血清同型半胱氨酸与叶酸、维生素B12水平的变化

目的 探讨冠心病患者血清同型半胱氨酸(HCY)与叶酸、维生素B12浓度的变化及其相关性。方法 选择84例经冠状动脉造影术证实为冠心病的患者，应用荧光偏振免疫分析法(FPIA)测定血清HCY浓度，离子捕获免疫分析法(ICIA)测定血清叶酸浓度，非均相微粒子酶免疫分析法（MEIA)测定血清维生素B12浓度。结果 冠心病患者血清HCY浓度增高，与正常对照组比较有显著性意义(P＜0．001)，而叶酸、维生素B12浓度则降低，与正常对照组比较有显著性意义(P＜0．001)，以上两种变化呈负相关(P＜0．001)。结论 同型半胱氨酸血症是冠心病的新的独立危险因素，叶酸、维生素B12缺乏可能是诱发高HCY的重要因素。     

The predictive value of specific immunoglobulin E levels for the first diagnosis of cow''s milk allergy. A critical analysis of pediatric literature

Investigators have tried to identify a level of seric specific immunoglobulin E (IgE) that had a sufficient predictive value to diagnose a food allergy without having will resort to the food challenge. To search in literature, all the studies that have estimated the possibility to identify a level of seric specific cow milk IgE with a positive predictive value (PPV) of 95% for the first diagnosis of cow's milk allergy (CMA) in pediatric age. We have identified six studies, nearly all studies suffer from relevant methodological bias. Proposed cut-off are all different. The studied pediatric populations were highly selected. Also neglecting the methodological bias of the studies and the great difference of value between the proposed cut-off, it always remains to consider that the pre-test probability of having a CMA between the children enrolled in the six studies included in this review is particularly high. The likelihood ratio helps to transfer the results of a study on a diagnostic test just to our population, and it is more realistic rather than to entrust itself to the PPV or the negative predictive value, that are much influenced from the prevalence of the disease in the studied population.     

钙调素拮抗剂E6对大鼠脑一氧化氮合酶活性和突触体谷氨酸释放的影响

目的 探讨钙调素拮抗剂E6的抗脑缺血作用机制。方法 用[3H]-L-Glu（glutamic　acid,Glu）标记大鼠脑突触体,测定突触体的Gln释放量和用一氧化氮合酶（nitric oxide synthase,NOS）试剂盒测定成年大鼠脑匀浆上清中NOS活性。结果　E6促进Glu释放（与对照组比,10-5mol·L-1组增加81.0％）,但对KCl（50 mmol·L-1）引起的Glu释放有抑制作用,10-5mol·L-1E6的抑制率为23.2％。E6浓度依赖性地抑制NOS活性。钙调素（calmodulin,CaM）（30μg·ml-1）可逆转E6的抑制作用（10-6mol·L-1E6的抑制率为13.7％）,N-硝基-精氨酸（（N-nitro-arginine,L-NNA）（10μmol·L-1）可加强E6的抑命作用（10-6mol·L-1的抑制率为76.5％）。结论 E6是与CaM结合后发挥抑制 NOS活性效应的,E6对Glu 释放的影响可能与其对NOS活性及其对神经细胞内Ca2+影响有关。     

维生素E对高脂血症的影响

本文报道用高脂饲料造成家兔高脂血症的研究。经6周后,测定血脂、脂蛋白及血浆假胆硷脂酶等项指标,高脂组各项指标均明显高于对照组,但高脂加维生素E组的各项指标均低于高脂组,结果说明维生素E能降低兔的高脂血症。     

Type II pneumocytes modulate surfactant production in response to cigarette smoke constituents: Restoration by vitamins A and E

This study was to evaluate the effects of cigarette smoke constituents upon type II pneumocyte surfactant production in vitro, and how vitamins A and E may alter the response. Freshly isolated type II pneumocytes from Sprague–Dawley rats were incubated 20 h in medium with fetal bovine serum that was or was not treated with cigarette smoke. The number of adherent cells was inversely related to the dose of smoke or benzo(a)pyrene. Despite the decreased number of treated cells, the total amount of surfactant per culture well was unchanged, whereas surfactant production per cell was significantly increased (P < 0.05). Vitamin A concentration was significantly (P < 0.05) lower in the smoke-treated serum compared with untreated serum. When vitamin A or E was added to the cigarette smoke-treated serum, cell adherence and surfactant production returned to control values. In conclusion, cigarette smoke constituents or benzo(a)pyrene alone decreased the number of adherent type II pneumocytes, but did not alter surfactant amounts because of an increased production of surfactant per cell. Type II pneumocytes seem to adjust surfactant production dependent upon the number of type II pneumocytes to produce it and vitamin A or E enhance cell attachment in the presence of the smoke toxins.     

Effect of prostaglandin E1 on graft function of kidneys from living related donors

Prostaglandin E₁ (PGE₁) was used in renal transplant recipients with living related donors. The drug was given intravenously from day 1 to day 7 after transplantation at a dose of 40 µg/kg twice a day. A total of 45 patients were studied divided into two groups: 25 patients were treated with PGE₁ (group B) and the remaining 20 patients did not receive the drug (group A). In group B, 24-h creatinine clearance (Ccr) was 66 ± 12.8 ml/min compared with 40.3 ± 13.4 ml/min in group A on the fifth postoperative day (P < 0.05). Urinary levels of N-acetyl-β-d -glucosaminidase (NAG) and serum levels of platelet factor 4 (PF4) in group B were significantly lower than in group A. On the fourth postoperative day, the urinary excretion of thromboxan B₂ (TxB₂) in group A was higher than in group B, but not significantly (5.1 ± 3.0 ng/day and 2.8 ± 1.1 ng/day, respectively). Acute rejection occurred in four patients in group B and in 10 patients (40%) in group A. The percentage of Leu2a-positive lymphocytes in group B was higher than in group A. We conclude that postoperative administration of PGE₁ improves graft function in kidneys from living related donors.     

2型糖尿病患者载脂蛋白E基因多态性的研究

目的：探讨中国人2型糖尿病患者载脂蛋白E（apoE)基因多态性及其与血脂和载脂蛋白水平的关系。方法：采用聚合酶链反应－限制性酶切片段长度多态性法，分别对74例2型糖尿病患者及191例血脂、血糖正常且无糖尿病史者的apoE基因型、空腹血脂及载脂蛋白AI、AⅡ、B100、CⅡ、CⅢ及E进行全面分析。结果：2型糖尿病患者的血清甘油三酯（TG）、总胆固醇（TC），低密度脂蛋白胆固醇（LDLC），非高密度脂蛋白胆固醇（nHDLC),载脂蛋白B100、CⅡ、CⅢ、E水平及TG／HDLC比值较对照组显著升高（P＜0．01）；血清高密度脂蛋白胆固醇（HDLC），apoE/apoCⅢ比值显著降低（P＜0．05）。2型糖尿病组与对照组apoE基因频率分布无显著性差异（P＞0．05）。携带ε2等位基因组血清TG／HDLC比值较E3／3基因型显著降低；而携带ε4等位基因组血清apoAⅡ水平较E3／3基因型及携带ε2等位基因组显著升高（P＜0．001）。结论：2型糖尿病患者apoE基因多态性与血TG／HDLC及apoAⅡ有一定关联。