Friday,December 8, 1995 8Th Annual San Antonio flow cytometry forum

Summary Pseudomonas exotoxin has been genetically modified so that it targets cancer cells. This was accomplished by deleting its cell binding domain and replacing it with Fv fragments of antibodies that react with breast, colon, and other cancers. Several recombinant immunotoxins are now in clinical trials.Presented at the symposium "New Approaches in the Therapy of Breast Cancer", Georgetown University Medical Center, Washington DC, October 1994, generously supported by an education grant from Bristol-Myers Squibb.     

Use of cardiopulmonary bypass for thrombectomy in acute superior vena cava syndrome

An increasing incidence of nonmalignant, indwelling catheter cases has been reported in relation to superior vena cava syndrome. Such cases may be life-threatening, with rapid development of facial and neck edema and the production of respiratory distress. This is the first reported case of atrial and superior vena caval thrombectomy requiring cardiopulmonary bypass; it is only the second case reported in which operative thrombectomy has been used. Because of the problems associated with an increase in the use of indwelling venous catheters and the satisfactory results we obtained in this case, such an aggressive form of treatment for acute, benign superior vena cava syndrome may be used more frequently in the future.     

Assessment of the mutagenicity of dichloroacetic acid in lacI transgenic B6C3F1 mouse liver

Dichloroacetic acid (DCA) is a chlorination byproduct found in finished drinking water. When administered in drinking water this chemical has been shown to produce hepatocellular adenomas and carcinomas in B6C3F1 mice over the animal's lifetime. In this study, we investigated whether mutant frequencies were increased in mouse liver using treatment protocols that yielded significant tumor induction. DCA was administered continuously at either 1.0 or 3.5 g/l in drinking water to male transgenic B6C3F1 mice harboring the bacterial lacI gene. Groups of five or six animals were killed at 4, 10 or 60 weeks and livers removed. At both 4 and 10 weeks of treatment, there was no significant difference in mutant frequency between the treated and control animals at either dose level. At 60 weeks, mice treated with 1.0 g/l DCA showed a 1.3-fold increase in mutant frequency over concurrent controls (P = 0.05). Mice treated with 3.5 g/l DCA for 60 weeks had a 2.3-fold increase in mutant frequency over the concurrent controls (P = 0.002). The mutation spectrum recovered from mice treated with 3.5 g/l DCA for 60 weeks contained G:C-->A:T transitions (32.79%) and G:C-->T:A transversions (21.31%). In contrast, G:C-->A:T transitions comprised 53.19% of the recovered mutants among control animals. Although only 19.15% of mutations among the controls were at T:A sites, 32.79% of the mutations from DCA-treated animals were at T:A sites. This is consistent with the previous observation that the proportion of mutations at T:A sites in codon 61 of the H-ras gene was increased in DCA-induced liver tumors in B6C3F1 mice. The present study demonstrates DCA-associated mutagenicity in the mouse liver under conditions in which DCA produces hepatic tumors.      

Fatty acid balance studies in term infants fed formula milk containing long-chain polyunsaturated fatty acids

Long-chain polyunsaturated fatty acids (LCP) are thought to be required for optimal nervous system development in the newborn. A commercial milk formula containing LCP (Aptamil-LCP) with a fatty acid profile closely resembling breast milk, has recently been introduced for term infants. The absorption of fatty acids in term infants was examined in a double-blind randomized controlled trial comparing Aptamil-LCP ( n = 20) and standard Aptamil ( n = 20). Formula-fed newborn infants were studied from birth for 14 d. Fat balances (3 d) were performed from d 10. A 3-d stool collection was performed from d 10 in a parallel breastfed group ( n = 21). Plasma samples were taken on d 6. Median fat excretion (mg kg⁻¹) was 897.1, 615.0 and 355.2 with Aptamil, Aptamil-LCP and breastfeeding, respectively. The median total fat absorption coefficient in Aptamil-LCP-fed infants was higher than in those fed standard Aptamil ( p < 0:01). These findings were accounted for by differences in the excretion and absorption of long-chain saturated fatty acids (C14:0, C16:0 and C18:0). Higher fat excretion was associated with bulkier and firmer stools. Only trace amounts of LCP were detected in the stools of all groups. This accounted for less than 4% of dietary intake in Aptamil-LCP-fed infants. No differences in the utilization of LCP from Aptamil-LCP and breast milk feeding were apparent. Plasma phospholipid fatty acid composition data reflected differences in dietary LCP intake. Thus, PL LCP levels were highest in the breastfed infants and lowest in the Aptamil-fed infants, with values for the Aptamil-LCP-fed group falling in between.     

Imaging of malignant lymphomas with F-18 FDG coincidence detection positron emission tomography

PURPOSE: The authors evaluated the utility of F-18 fluorodeoxyglucose (FDG) coincidence detection (CoDe) positron emission tomography (PET) for staging, post-treatment evaluation, and follow-up assessment of patients with malignant lymphomas. MATERIALS AND METHODS: Fifty-eight patients with histologically proved malignant lymphomas (4 Hodgkin's disease, 54 non-Hodgkin's lymphoma) underwent CoDe PET using F-18 FDG. CoDe PET was performed using a dual-head gamma camera equipped with coincidence detection circuitry. Of the 87 CoDe PET studies, 26 were performed for staging, 38 for post-treatment evaluation, and 23 for follow-up evaluation of recurrence. The entire trunk, from the cervical to the inguinal regions, or selected regions were scanned with the patient in the supine position. No attenuation correction was made and reconstruction was performed using filtered back-projection rather than iterative reconstruction. CoDe PET findings were compared with corresponding results of computed tomographic (CT) and magnetic resonance imaging (MRI), tissue biopsy, or clinical follow-up. RESULTS: For staging, 52 sites were positive on CoDe PET or CT-MRI. CoDe PET detected 49 sites (94%), and CT-MRI showed 47 sites (90%). CoDe PET detected five more lymphomatous lesions and missed three lesions. For post-treatment evaluation, CoDe PET showed a positive predictive value of 100% and a negative predictive value of 83%, but the validated cases numbered only 11. For follow-up for recurrence, CoDe PET had a negative predictive value of 90%, but frequent false-positive findings were noted in the head and neck region as a result of underlying inflammatory changes. CONCLUSIONS: For staging, FDG CoDe PET alone without attenuation correction is not sensitive enough to be used as an independent imaging method, especially for small abdominal lesions. However, it appears to be an accurate method for assessing residual disease and for patient follow-up.     

安徽省2007～2008年志贺氏菌流行株菌型分布及脉冲场分子分型

目的了解安徽省志贺氏菌的流行菌型,并建立脉冲场凝胶电泳（PFGE）分子分型方法,为菌痢防控提供理论基础。方法对22株志贺氏菌进行血清分型、药物敏感试验和PFGE试验。结果22株志贺氏菌血清分型：B群19株,占总数86.5%;C群1株,占总数的4.5%;D群2株,占总数的9.0%。成功建立了菌痢的PFGE分子分型方法,并将我省22株流行株分为若干带型。试验结果进一步作聚类分析。结论安徽省菌痢流行株以福氏为主;安徽省PFGE分子分型方法和初步带型数据库对提高细菌检测水平有一定意义。     

Pellagra in a child–A rare entity

This case has been presented as pellagra, which is very rare in children. Pellagra is due dietary deficiency of niacin. Usually seen in alcoholics, malabsorption syndromes occur very rarely in children. A 11-y-old girl presented with well-defined, hyperpigmented, hyperkeratotic, symmetrical, thick scaly plaques surrounded by erythema on the dorsum of the hands, arms, feet, legs up to knees, and along the sides of the neck. The child was given 100 mg of Nicotinamide. Skin lesions resolved rapidly with the treatment and the child improved.     

超声对甲状腺术后瘢痕组织的诊断应用

甲状腺术后瘢痕组织是甲状腺局部分切除术后由于手术方式及缝线填充而形成的组织,甲状腺术后瘢痕组织形成及其发生发展过程同一般的组织损伤修复病理过程一样,为渐进老化阶段的结缔组织,其内小血管稀少,胶原纤维增多[1]。由于甲状腺术后瘢痕组织其质地较硬,活动性差,超声声像图上表现缺乏典型特征,与癌灶极其相似,因此鉴别较困难。本文将介绍超声对于甲状腺术后的随诊应用,分析甲状腺术后瘢痕组织的超声检查特点并着重介绍超声动态观察甲状腺术后瘢痕组织的应用及其发展前景。     

全反式维甲酸联合5-氟尿嘧啶对Eca109细胞增殖、迁移和VEGF表达的影响

目的:探讨全反式维甲酸(ATRA)、5-氟尿嘧啶(5-FU)单独或联合作用对Eca109细胞增殖、迁移和血管内皮生长因子(VEGF)表达的影响。方法:将常规传代的Eca109细胞分为4组:ATRA组、5-FU组、ATRA+5-FU组和对照组,采用MTT法检测各组细胞的增殖情况,通过划痕实验测定各组细胞的迁移能力,采用RT-PCR和免疫细胞化学法分别检测各组细胞VEGF mRNA和蛋白的表达情况。结果:作用24、48和72 h后,ATRA+5-FU组的细胞生长抑制率均高于其他2组(F=23.432、13.605、73.369,P均<0.05);作用24 h后,ATRA+5-FU组的迁移率均低于其他3组(P均<0.001);作用48 h后,ATRA+5-FU组细胞VEGF mRNA和蛋白的相对表达量均低于其他3组(P均<0.05)。结论:ATRA、5-FU均能抑制食管癌细胞的增殖,且联合用药效果更为显著,可能与其抑制肿瘤血管生成有关。