广州队列研究生物库中条形码技术应用与评价

目的建立大规模人群的分子流行病学队列研究生物库，确保快速、准确地识别每一份生物样本，并保持其活性，以便长时间跟踪研究。方法采用条形码识别技术对血液样品的采集、处理及存储、查询过程进行全程管理。结果创建成功以条形码自动识别技术为核心的新型运作管理模式，建立起10000人份的生物样品库。大型生物样本库实施条形码管理系统可缩短每份样品的处理时间，提高工作效率1．5倍。结论条形码技术的应用可有效地避免样品间的相互混淆，使实验室每一项工作准确、可靠、高效，实现医学研究工作全面信息化，提高基因队列研究的质量。     

The relationship between CR3 deficiency and neutrophil actin assembly

Polymorphonuclear leukocytes (PMN) with a deficiency of the complement receptor type 3 (CR3) membrane glycoprotein family have impairments in the ability to adhere to surfaces as well as chemotactic and phagocytic defects, processes that require a functional contractile apparatus. PMN from the patient with neutrophil actin dysfunction (NAD) displayed similar functional characteristics to those with CR3 deficiency suggesting the two disorders may be the same disease. In order to evaluate the relationship between CR3 deficiency and actin assembly, actin filament assembly was measured in PMN from six previously reported homozygotes (two severe and four moderate CR3-deficient patients) as well as five heterozygotes for CR3 deficiency. PMN from all patients had normal unstimulated concentrations of F-actin and after exposure to the chemotactic peptide FMLP (5 x 10(-7) mol/L for 5 to 40 seconds at 25 degrees C) assembled actin normally. Pretreatment of normal PMN with concentrations of monoclonal anti-alpha CR3 antibody, capable of blocking PMN adherence, also failed to impair FMLP- induced actin filament assembly. CR3 glycoprotein expression was measured in PMNs from the mother, father, and older sister of the NAD patient (N Engl J Med 291:1093, 1974). Actin filament assembly was recently shown to be defective in PMNs from all three family members. The total concentrations of the alpha and beta CR3 subunits were below normal in PMN detergent extracts from the mother (25% of simultaneous controls) and older sister (56% of control). PMN surface expression of these two subunits was also found to be depressed (mother, 50%; older sister, 63% of control). These findings suggest these two NAD family members are heterozygote carriers for CR3 deficiency as well as NAD. Simultaneous studies of the father, however, demonstrated normal total concentrations of both the alpha and beta CR3 subunits (126% of controls) as well as normal surface expression of both subunits after phorbol myristate acetate stimulation and incubation at 37 degrees C (mean, 112% of controls) but slightly lower than normal levels after FMLP stimulation (mean, 83%). These findings indicate that CR3 deficiency generally is not associated with defective actin filament assembly and support the conclusion that NAD represents a unique kindred in which PMN actin function differs from previously reported genotypes of CR3 deficiency.     

Four categories of gamma-globin gene triplications: DNA sequence comparison of low G gamma and high G gamma triplications

The human fetal gamma chains are produced by closely linked G gamma and A gamma genes, and unequal crossing over between them leads to gamma gene deletions and triplications. Nine gamma gene triplications from seven ethnic groups were analyzed for G gamma and hemoglobin F (Hb F) values of heterozygotes and for the presence of polymorphic XmnI restriction sites 5' to the gamma genes. Four categories of triplication were found: I had low G gamma and low Hb F values and lacked XmnI sites 5' to the three gamma genes [---]. II had high G gamma and slightly elevated Hb F values but was also [---]. III was similar to II, except that XmnI was [+--]. IV had very high G gamma and slightly elevated Hb F values, and XmnI was [++-]. One case each of triplications I and IV were cloned into Charon 35. For both, the two 5' gamma gene code for G gamma chain, while the 3' gamma gene codes for A gamma chain. DNA sequencing showed that the unequal crossover occurred between 472 and 398 base pairs (bp) 5' to the gamma gene Cap sites (- 472 and -398) for the type IV triplication and between -271 and codon 136 for the type I triplication. In addition, type I had a 4-bp deletion of AGCA from -225 to -222. The high G gamma values of the type IV triplication are explained by its -G gamma-G gamma-A gamma-gene arrangement and the XmnI sites 5' to the G gamma genes. We hypothesize that the low G gamma value of the type I triplication, which is also -G gamma-G gamma-A gamma-, is due to inactivation of the middle G gamma gene by the AGCA deletion at -225 to -222.     

The value of 2-D Doppler echocardiography in the evaluation of asymptomatic patients with Mustard operation for transposition of the great arteries

2-D Doppler echocardiography was used to assess the occurrenceof haemodynamic abnormalities in 45 asymptomatic patients, aged4 to 16 years (median 7·4) after a Mustard operationfor transposition of the great arteries. The findings were comparedwith those derived from cardiac catheterization. Thirty-fivecardiac lesions were correctly diagnosed by 2-D Doppler echocardiographyin 23 patients, but on six occasions, minor abnormalities weremissed. 2-D Doppler echocardiography demonstrated systemic venouspathway obstruction of more than 3 mmHg at cardiac catheterizationin nine patients, and in five of the six patients with pulmonaryvenous channel obstruction. A left ventricular outflow tractobstruction (pressure difference > 15 mmHg) was diagnosedcorrectly by Doppler echocardiography in seven patients. Baffleleakage was found in two patients with a left to right shuntof 25% or more of pulmonary bloodflow, but was missed in fiveout of nine patients with small shunts. Tricuspid regurgitationwas well defined in eight patients, The absence of symptomsand a routine examination after a Mustard operation do not ruleout haemodynamic abnormalities. However, these, with the possibleexception of minor baffle leakage, can be detected by 2-D Dopplerechocardiography.     

Cell cycle progression of B-chronic lymphocytic leukemia cells induced to differentiate by TPA

The cell cycle transition and differentiation-associated surface antigen expression was studied in a clone of B cell chronic lymphocytic leukemia (B-CLL) with phenotypic properties similar to those of resting B lymphocytes. Differentiation was induced with TPA (12-O-tetradecanoyl- phorbol-13-acetate) and defined and quantitated by morphological and functional markers. Changes in the cell cycle position were determined by flow cytometry of acridine orange-stained cells. The uninduced B-CLL cells represented a homogeneous population with the same cell cycle position (GO) as resting normal peripheral blood lymphocytes. After five days of TPA stimulation, 56% of the B-CLL cells were found in G1A, 9% in G1B, and 3% in the S + G2/M phase, of which 2% was accounted to proliferating T cells. The cell cycle transition of the differentiating B-CLL cells was also examined using cell cycle-associated surface antigens as markers. HLA-DR and CD23 antigens were present already on noninduced cells. The former had a high constant expression, while the amount of CD23 increased upon induction. The 4F2 antigen was absent on noninduced cells but present on 86% of the induced cells. HH1 (CD37) was expressed by the majority of the cells before TPA treatment and decreased to almost undetectable levels within 24 hours. Two antigens related to late stages of the cell cycle, the interleukin 2 (IL 2; CD25) and the transferrin receptor, were present on about 20% of the induced cells. Experiments with enriched T cells showed that T but not B cells incorporated 3H-thymidine. Taken together these results and previous work on the induction of the protooncogene c-myc and c-fos suggest that this B-CLL clone represents GO cells that undergo differentiation without concomitant proliferation when exposed to TPA.