Advances in the prenatal diagnosis of hematologic diseases

Prenatal diagnosis of hematologic diseases can now be performed with fetal blood, fetal amniotic fluid cell DNA, and fetal chorionic villi DNA. Some hemoglobinopathies can be detected by all three methods, and the choice will depend on the available obstetric and laboratory techniques, as well as the time of presentation of the pregnancy. Hopefully, further development of molecular probes and techniques will soon expand these options to all of the globin disorders. Detection of coagulation disorders in utero currently requires samples of pure fetal blood. Gene cloning is accomplished for some (factor IX and antithrombin III) and is underway for others (factor VIII), and further investigation is necessary to determine whether deficiencies in these gene products are due to gene deletion or to mutant genes linked to polymorphic restriction enzyme sites of diagnostic use. Thus, molecular biology may be applied to prenatal diagnosis of the clotting problems, but this has not yet been accomplished. Disorders affecting the number and/or function of erythrocytes, leukocytes, and platelets can be diagnosed by analysis of fetal blood. Blood samples will continue to be required until more is known about the molecular biology of hematopoiesis. Syndromes that can be diagnosed by chromosome studies should be revealed in cultures of amniotic fluid cells, fetal blood lymphocytes, and chorionic villi cells. Cultured cells can be examined for karyotypes, Y-chromatin, spontaneous or induced chromosome breakage, DNA repair, SCEs, and translocations. The techniques for culturing amniotic cells and fetal blood white cells are established, and those for growing cells from chorionic villi are improving rapidly. Direct preparations of cells from villi only may suffice for some of the above analyses. The study of hematologic disease in utero has thus come full circle, from the use of amniotic cells to determine the sex in X-linked disorders, to fetal blood sampling for the analysis of gene products, then back to amniocentesis for DNA, and now earlier in gestation to chorionic villi. All of this has occurred in less than ten years, and it is anticipated that developments in the next ten years will be equally dramatic. The future should bring all prenatal testing into the first trimester, use molecular probes, and provide for both early diagnosis and early treatment of genetic hematologic disease.     

河北省4个地区广泛焦虑症的流行病学调查

目的:了解广泛焦虑症的患病率及人口学特点。方法:于2004-10/2005-03随机抽取河北省邯郸、保定、秦皇岛、承德4个地级市18岁以上人口进行全省精神疾病流行病学现场抽样调查工作,总样本24000人。调查筛选工具采用改编后的一般健康问卷12项,以《DSM-Ⅳ-TR轴Ⅰ障碍定式临床检查》病人版为调查的诊断工具。根据被调查者一般健康问卷12项总分,把被调查者分为高危人群、中危人群、低危人群3类。根据预试验调查结果确定三段危险人群的分界分:总分≥4分属于高危人群,高危人群全部进行DSM-Ⅳ-TR轴Ⅰ障碍定式临床检查;总分为2分或3分即属中危人群,中危人群约40%需进行DSM-Ⅳ-TR轴Ⅰ障碍定式临床检查,总分为0分或1分即属低危人群,低危人群中10%需进行DSM-Ⅳ-TR轴Ⅰ障碍定式临床检查。改编后的一般健康问卷12项分数及内容不变,另外增加8个问题均为高危因素,并进行DSM-Ⅳ-TR轴Ⅰ障碍定式临床检查。结果:①实际完成调查20716人,其中男10343人(49.9%),女10373人(50.1%)。共诊断焦虑症患者127例。②按高中低危因素调整后时点患病率为7.69/1000(95%CI6.50/1000～8.88/1000)。城市患病率4.87/1000,农村患病率8.10/1000,两者差异无显著性意义(u=1.78,P>0.05)。女性患病率明显高于男性,差异有显著性意义(分别为10.42/1000,4.97/1000,u=4.49,P<0.01),男女患病率比例为1:2.10。按不同年龄阶段的人口计算出各年龄段的时点患病率,20～29岁患病率较低(3.17/1000),50～59岁患病率较高(15.56/1000)。③通过12个因素的Logistic回归分析发现,影响广泛焦虑症的危险因素有年龄50～59岁(OR=1.713);保护性因素男性(OR=0.431),年龄20～29岁(OR=0.393),收入10001～20000元(OR=0.568),收入20001～40000元(OR=0.117)。结论:广泛焦虑症的流行病学特征为女性、中老年人患病率较高,男性、青年、收入中等者患病率较低。     

Detection of CYP1A1 protein in human liver and induction by TCDD in precision-cut liver slices incubated in dynamic organ culture

Cytochrome P4501A1 (CYP1A1) has been implicated in the conversion of numerous polycyclic aromatic hydrocarbons into electrophilic species capable of binding covalently to DNA and has therefore been postulated to be involved in the initiation of carcinogenesis. The expression of CYP1A1 protein appears not to be constitutive, but is readily inducible by aryl hydrocarbon (Ah) receptor ligands in a majority of tissues of experimental animals, especially the liver. To date, there is conflicting evidence for the expression or inducibility of CYP1A1 protein in human liver. In this present study, we report the detection of CYP1A1 in all 20 human liver microsomal samples tested by standard western immunoblotting with chemiluminescent detection using a specific monoclonal antibody (mAb 1-12-3) directed against a marine fish (scup) cytochrome P450E. mAb 1-12-3 has been shown previously to specifically recognize CYP1A1 in mammals. This system consistently demonstrated a detection sensitivity as low as 0.01-0.025 pmol CYP1A1 per lane. In the samples where CYP1A1 protein levels were quantitated, CYP1A1 ranged from approximately 0.4 to 5 pmol CYP1A1/mg microsomal protein. Additionally, the inducibility of CYP1A1 protein was demonstrated by incubating precision-cut human liver slices in dynamic organ culture for up to 96 h in the presence of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The specificity of mAb 1-12-3 was tested using several purified human and rat cytochrome P450s to ensure that the protein being detected was CYP1A1. mAb 1-12-3 did not cross-react with human CYP1A2 or CYP3A4 or rat CYP1B1, but did strongly recognize CYP1A1. However, there was a very weak cross-reactivity of mAb 1-12-3 with human CYP2E1, approximately 75-fold less compared with CYP1A1. In order to confirm CYP1A1 as the immunoreactive protein detected in human liver, microsomal samples were subjected to two-dimensional electrophoresis involving isoelectric focusing followed by SDS-PAGE and immunoblotting. Utilizing mAb 1-12-3, the human liver microsomal samples displayed an immunoblotting profile matching that obtained from a microsomal preparation from a AHH-1 TK+/- cell line expressing solely human CYP1A1 and differing from the profile obtained using a polyclonal antibody directed against CYP2E1 and cells expressing CYP2E1. Furthermore, mAb 1- 12-3 recognized only one protein of identical mobility on the two- dimensional blots from human liver microsomes and AHH-1 TK+/- cells expressing CYP1A1, while displaying no reaction to cells expressing only CYP2E1. In conclusion, CYP1A1 appears to be expressed in human liver at low levels and is inducible upon exposure to TCDD.      

Extradural cavernous haemangioma simulating a disc protrusion

Cavernous haemangiomas confined to the epidural space are rare and are therefore infrequently considered in the differential diagnosis of spinal epidural masses. In order to draw attention to this diagnosis, a case in which an epidural cavernous haemangioma simulates a lateral/foraminal disc protrusion is presented.