Dynamic changes in the platelet granule membrane glycoprotein level in patients with acute myocardial infarction]

Platelet granule membrane glycoprotein (GMP-140) level was measured by using 125I labelled monoclonal antibody (SZ-51) in 20 patients with acute myocardial infarction in the first three days and at the first three weekends. The correlation of severe arrhythmia and administration of aspirin with platelet GMP-140 in AMI were studied respectively. It is shown that platelet GMP-140 increased significantly in the first three days after AMI, then it dropped quickly, but remained at high level as compared with the controlled group till the third weekend (P < 0.01). Platelet GMP-140 level was higher in the first three days than at the first three weekends (P < 0.01). The changes of platelet GMP-140 have not been shown to be related with severe arrhythmia or administration of aspirin (P > 0.05). The results indicated that the platelets in AMI are activated continuously in the first three weeks after infarction; it might be thought as an important index of coronary artery thrombus formation.     

Haemoglobin Q-Thailand and hereditary spherocytosis in a Chinese family.

A Chinese family with concurrent hereditary spherocytosis (HS) and haemoglobin (Hb) Q-Thailand is described. The Hb Q-Thailand mutation was found on the remaining alpha1 globin gene on a chromosome 16 containing the (-alpha 4.2) deletion. Active haemolysis in members of this family is segregated with the HS phenotype, and the Hb Q-Thailand in the heterozygous state does not seem to show any modulating effect on HS.     

PPARgamma regulates adipocyte cholesterol metabolism via oxidized LDL receptor 1

In addition to its role in energy storage, adipose tissue also accumulates cholesterol. Concentrations of cholesterol and triglycerides are strongly correlated in the adipocyte, but little is known about mechanisms regulating cholesterol metabolism in fat cells. Here we report that antidiabetic thiazolidinediones (TZDs) and other ligands for the nuclear receptor PPARgamma dramatically upregulate oxidized LDL receptor 1 (OLR1) in adipocytes by facilitating the exchange of coactivators for corepressors on the OLR1 gene in cultured mouse adipocytes. TZDs markedly stimulate the uptake of oxidized LDL (oxLDL) into adipocytes, and this requires OLR1. Increased OLR1 expression, resulting either from TZD treatment or adenoviral gene delivery, significantly augments adipocyte cholesterol content and enhances fatty acid uptake. OLR1 expression in white adipose tissue is increased in obesity and is further induced by PPARgamma ligand treatment in vivo. Serum oxLDL levels are decreased in both lean and obese diabetic animals treated with TZDs. These data identify OLR1 as a novel PPARgamma target gene in adipocytes. While the physiological role of adipose tissue in cholesterol and oxLDL metabolism remains to be established, the induction of OLR1 is a potential means by which PPARgamma ligands regulate lipid metabolism and insulin sensitivity in adipocytes.     

Should we screen for globin gene mutations in blood samples with mean corpuscular volume (MCV) greater than 80 fL in areas with a high prevalence of thalassaemia?

AIMS: To investigate whether it is worthwhile, in areas where thalassaemia is common, to screen for globin gene mutations in subjects with a mean corpuscular volume (MCV) above 80 fL, especially in partners of known thalassaemia carriers. METHODS: Blood samples from 95 subjects with MCV between 80 and 85 fL were screened for the presence of alpha globin gene mutations and the haemoglobin (Hb) E mutation. RESULTS: Thirty four subjects harboured globin gene mutations. Of these, 31 had deletions of one alpha globin gene, one had Hb Constant Spring, and three had Hb E mutations. CONCLUSION: Based on the above figures and known prevalence rates of thalassaemia carriers, it would seem worthwhile to screen for globin gene mutations in partners of known thalassaemia carriers, regardless of MCV, to identify pregnancies at risk of Hb H disease or Hb E/beta thalassaemia.     

Immunoglobulin mimicry by Hepatitis C Virus envelope protein E2

Hepatitis C virus (HCV) establishes persistent infection in the majority of infected individuals. The currently accepted hypothesis of immune evasion by antigenic variation in hypervariable region 1 (HVR1) of glycoprotein E2 does not however, explain the lack of subsequent immune recognition. Here, we show that the N-terminal region of E2 is antigenically and structurally similar to human immunoglobulin (Ig) variable domains. E2 is recognized by anti-human IgG antibodies and also possesses common amino acid (aa) sequence features of the conserved v-gene framework regions of human Ig light chains in particular but also heavy chains and T cell receptors. Using a position specific scoring system, the degree of similarity of HVR1 to Ig types correlated with immune escape and persistence in humans and experimentally infected chimpanzees. We propose a unique role for threshold levels of Ig molecular mimicry in HCV biology that not only advances our concept of viral immune escape and persistent infection but also provides insight into host-dependent disease patterns.     

Reduced-order parameter optimization for simplifying prostate IMRT planning

Intensity-modulated radiotherapy (IMRT) has become an effective tool for cancer treatment with radiation. However, even expert radiation planners still need to spend a substantial amount of time manually adjusting IMRT optimization parameters such as dose limits and costlet weights in order to obtain a clinically acceptable plan. In this paper, we describe two main advances that simplify the parameter adjustment process for five-field prostate IMRT planning. First, we report the results of a sensitivity analysis that quantifies the effect of each hand-tunable parameter of the IMRT cost function on each clinical objective and the overall quality of the resulting plan. Second, we show that a recursive random search over the six most sensitive parameters as an outer loop in IMRT planning can quickly and automatically determine parameters for the cost function that lead to a plan meeting the clinical requirements. Our experiments on a ten-patient dataset show that for 70% of the cases, we can automatically determine a plan in 10 min (on the average) that is either clinically acceptable or requires only minor adjustment by the planner. The outer-loop optimization can be easily integrated into a traditional IMRT planning system.     

第四跖背动脉逆行岛状皮瓣在第二足趾再造手指供区趾蹼皮肤缺损中的临床应用

目的探讨第四跖背动脉逆行岛状皮瓣修复第二足趾再造手指后供区趾蹼皮肤缺损的临床应用效果。方法2007年1月~2009年12月,均为切取第二足趾再造手指时携带面积不等的跖背皮瓣13例患者的临床资料进行分析。结果术后13例转移皮瓣全部存活,术后随访时间为3~16个月,皮瓣质地、感觉良好,趾蹼外形满意,供足行走功能满意。结论最大限度地保护了供足的功能,减少了植皮后并发症,是较为理想的手术方式。     

Segmentation and reconstruction of hepatic veins and intrahepatic portal vein based on the coronal sectional anatomic dataset

Three-dimensional (3D) reconstruction of intrahepatic vessels is very useful in visualizing the complex anatomy of hepatic veins and intrahepatic portal vein. It also provides a 3D anatomic basis for diagnostic imaging and surgical operation on the liver. In the present study, we built a 3D digitized model of hepatic veins and intrahepatic portal vein based on the coronal sectional anatomic dataset of the liver. The dataset was obtained using the digital freezing milling technique. The pre-reconstructed structures were identified and extracted, and then were segmented by the method of manual intervention. The digitized model of hepatic veins and intrahepatic portal vein was established using 3D medical visualization software. This model facilitated a continuous and dynamic displaying of the hepatic veins and intrahepatic portal vein at different orientations, which demonstrated the complicated relationship of adjacent hepatic veins and intrahepatic portal vein realistically in the 3D space. This study indicated that high-quality 2D images, precise data segmentation, and suitable 3D reconstruction methods ensured the reality and accuracy of the digital visualized model of hepatic veins and intrahepatic portal vein.