Holter系统的技术要求及神经网络方法

为了长时间、准确的记录分分析体表ＥＣＧ，从各个方面满足基础研究、临床、康复以及特殊生理需要，对Ｈｏｌｔｅｒ系统提出了愈来愈高的要求。作者从技术实现的角度讨论了Ｈｏｌｔｅｒ的主要技术要求，包括记录部分和分析部分；还介绍了几种用神经网络模型满足Ｈｏｌｔｅｒ系统技术要求的原理，包括用多层感知器实现数据压缩及分类，用高阶神经网络实现ＥＣＧ的分类，以及用ＡＲＴ模型识别ＥＣＧ中的Ｐ波与Ｔ波。     

川崎病休克综合征合并心力衰竭1例临床病例分析及文献复习

目的 探讨川崎病休克综合征 (Kawasaki Disease Shock Syndrome,KDSS) 合并心力衰竭的临床特征。方法 分析 1例KDSS合并心力衰竭患儿的临床资料,并复习相关文献。结果 KDSS在川崎病中不常见,但表现严重,在急性期可以导致循环衰竭,表现为心动过速、毛细血管充盈时间延长、四肢末端发凉、脉搏细弱、尿量减少或意识障碍等而发生全身循环衰竭,早期识别,及时给予人免疫球蛋白和激素等综合治疗可明显改善患者休克的状况。结论 KDSS是川崎病中少见但较为严重的临床并发症,早期识别及综合的临床治疗方法是减少KDSS的有效措施。     

烧伤诊疗信息管理系统的开发

系统主要以烧伤科病房管理为主，包括病人的诊治和用药管理。通过计算机对病人的用药及诊治进行分析、统计和查询。     

Measurement of human cytomegalovirus loads by quantitative real-time PCR for monitoring clinical intervention in transplant recipients

Quantitative monitoring of human cytomegalovirus (HCMV) infection is helpful in determining appropriate antiviral management of transplant recipients. Quantitative PCR technologies have demonstrated accuracy in measuring systemic HCMV loads. A total of 298 consecutive whole-blood specimens submitted to the Clinical Virology Laboratory at Vanderbilt University Medical Center from 15 February to 31 October 1999 were included in the study. In addition to a qualitative colorimetric microtiter plate PCR assay (MTP-PCR) and a semiquantitative pp65 antigenemia assay, each specimen was measured for HCMV loads by a quantitative PCR assay performed on an ABI PRISM 7700 Sequence Detection System (TaqMan). Compared to results of the MTP-PCR, the sensitivity, specificity, positive predictive value, and negative predictive value were 70.5, 97.5, 87.8, and 92.8% for the antigenemia assay and were 96.7, 92.0, 75.6, and 99.1% for the TaqMan assay, respectively. There was a high correlation between antigenemia values and HCMV loads as determined by the TaqMan (r = 0.989; P < 0.001). Antigenemia values of 0, 1 to 10, 11 to 100, 101 to 1,000, and over 1,000 positive cells per 2 x 10(5) leukocytes corresponded to median HCMV loads measured by TaqMan of 125, 1,593, 5,713, 16,825, and 5,425,000 copies/ml, respectively. Corresponding to antigenemia values of 1 to 2, 10, and 50 positive cells per 2 x 10(5) leukocytes, HCMV viral loads of 1,000, 4,000, and 10,000 copies/ml are proposed as cutoff points for initiating antiviral therapy in patient groups with high, intermediate, and low risk of CMV diseases.     

尿激酶型纤溶酶原激活物系统对骨巨细胞瘤细胞基质金属蛋白酶-2和组织基质金属蛋白酶抑制物-3表达的影响

目的:研究尿激酶型纤溶酶原激活物(uPA)及其受体(uPAR)信号转导对骨巨细胞瘤基质金属蛋白酶-2(MMP-2)和金属蛋白酶组织抑制物-3(TIMP-3)的调节。方法:用免疫组化检测骨巨细胞瘤组织中uPAR、MMP-2和TIMP-3的表达。用免疫共沉淀法检测uPA对瘤细胞信号转导通路的p44蛋白磷酸化水平。用蛋白印迹法检测用uPA和uPAR抗体处理后瘤细胞MMP-2和TIMP-3蛋白表达。结果:(1)uPAR主要表达在部分单核基质细胞和一些多核巨细胞的胞膜上;(2)MMP-2主要表达在瘤细胞的胞浆,在多核巨细胞,其表达有明显的极向性;(3)在骨巨细胞瘤组织TIMP-3表达量低于MMP-2,在多核巨细胞也显示极向性表达;(4)将uPA-ATF加入培养的骨巨细胞瘤细胞后,细胞信号通路上的p44蛋白磷酸化水平明显增高。用uPAR抗体处理后,细胞p44蛋白磷酸化水平明显降低。说明uPA-ATF参与细胞信号转导,而且受uPAR拮抗剂的影响;(5)uPA-ATF信号通路上调MMP-2和TIMP-3的表达,而uPAR抗体则下调MMP-2和TIMP-3的表达。结论:本实验首次直接证明uPA-ATF通过信号转导能调节MMP-2和TIMP-3的表达,而后者则在骨巨细胞瘤局部骨质吸收中起重要作用。     

In vivo expression and immunological studies of the 42-kilodalton carboxyl-terminal processing fragment of Plasmodium falciparum merozoite surface protein 1 in the baculovirus-silkworm system

The 42-kDa carboxyl-terminal processing fragment of Plasmodium falciparum merozoite surface protein 1 (MSP-1(42)) is an anti-erythrocytic stage malaria vaccine candidate. In this study, MSP-1(42) was expressed by using the Bombyx mori nuclear polyhedrosis virus-silkworm expression system, and the antigenicity and immmunogenicity of the recombinant protein, Bmp42, were evaluated. The average yield of Bmp42, as determined by a sandwich enzyme-linked immunosorbent assay (ELISA), was 379 microg/ml of infected silkworm hemolymph, which was >100-fold higher than the level attainable in cell culture medium. N-terminal amino acid sequencing revealed that Bmp42 was correctly processed in silkworm cells. Data from immunoblotting, as well as from the inhibition ELISA, suggested that the conformational B-cell epitopes of MSP-1(42) were recreated in Bmp42. Immunization of rabbits with Bmp42 in complete Freund's adjuvant generated high-titer antibody responses against the immunogen. Specificity analyses of the anti-Bmp42 antibodies using several recombinant MSP-1(19) proteins expressing variant and conserved B-cell epitopes suggested that the anti-Bmp42 antibodies recognized primarily conserved epitopes on MSP-1(19). Furthermore, the anti-Bmp42 antibodies were highly effective in inhibiting the in vitro growth of parasites carrying homologous or heterologous MSP-1(42). Our results demonstrated that the baculovirus-silkworm expression system could be employed to express biologically and immunologically active recombinant MSP-1(42) at elevated levels; thus, it is an attractive alternative for producing a protective MSP-1(42) vaccine for human use.     

Response of the xenograft endothelium in the concordant xenotransplantation

Objective: To investigate the response of the xenograft endothelium in the concordant hamster to rat cardiac xenotransplantation and the mechanism of acute vascular rejection. Methods: The animals were divided into 5 groups randomly: control group,CsA group, splenectomy group, D0 splenectomy+CsA group and D3 splenectomy+CsA group. Hamster heart was heterotopicaly transplanted to rat abdominal cavity. The graft survival was monitored by palpation of the rat abdominal wall. The histological and ultrastructural changes of the xenogafts were investigated. NF-κB and P-selectin expression in the xenograft were detected. Hene Oxigenase-1 and Bcl-2 expression were also detected in the xenografts of different groups. Results: The mean survival time of the xenografts in control group, CsA group, splenectomy group, D0 splenectomy+CsA group and D3 splenectomy+CsA group was 3.4±0.55, 3.8±0.45, 6.4±1.52, 30 and 7.4±1.14 days. The rejected graft showed typical acute vascular rejection in control group, CsA group,splenectomy group and D3 splenectomy+CsA group. Endothelial cells of the rejected xenograft showed dramatic assembly of ribosomes and expansion of the rough endoplasmic reticulum. However, the endothelium of the long-term survived grafts in D0 splenectomy+CsA group showed normal architecture. NF-κB and P-selectin expression were detected in the rejected xenografts. HO-1 expression was observed in the long-term survived xenografts in D0 splenectomy+CsA group. Conclusion: The endothelial cells of the xenograft might be activated during the acute vascular rejection. Expression of HO-1 might inhibit the upregulation of NF-κB and adhesion molecular which decreases the activation of the endothelium of the graft.     

White matter damage precedes that in gray matter despite similar magnetic resonance imaging changes following cerebral hypoxia-ischemia in neonatal rats

We hypothesized that the cerebral injury produced by hypoxia-ischemia (HI) in neonatal rats would differ in white compared with gray matter as detected histologically or with magnetic resonance (MR) imaging methods. Maps of T₂ and the apparent diffusion coefficient (ADC) of water were acquired in 1-week-old rats at times prior to cerebral HI (right carotid artery occlusion plus 1.5 h of hypoxia), within the last 5–10 min of HI, and 1 h or 24 h after HI. Near the end of HI, ADC decreased and T₂ increased in both cortical gray and subcortical white matter within the cingulum of the HI hemisphere. One hour after HI, ADC partially recovered, but T₂ remained increased and then increased further by 24 h post-HI. In contrast to the similar MR responses in white and gray matter, histological evidence for irreversible cell damage occurred in white matter earlier than in gray matter within the HI hemisphere. At 1 h post-HI, rarefied or disrupted nerve fibers and an increase in TUNEL-positive cells were observed within white matter in the cingulum, whereas neurons within the cortical gray matter appeared normal. By 24 h post-HI, damage was apparent in both white and gray matter. Thus, MR imaging detected acute tissue edema following cerebral HI in both gray and white matter but did not distinguish between the early irreversible tissue injury detected histologically in white but not gray matter in this rather severe model of neonatal encephalopathy.