Coronary artery and orifice development is associated with proper timing of epicardial outgrowth and correlated Fas-ligand-associated apoptosis patterns

The proepicardial organ provides differentiated cell types to the myocardial wall and facilitates coronary development. Ingrowth of the coronary arteries into the aorta has recently been linked to apoptosis. This study was set up to examine the effect of an inhibition of epicardial outgrowth on apoptotic patterning and coronary development. Epicardial outgrowth was blocked at HH15-17 in quail embryos, which survived until HH25-35 (n=33). Embryos with complete inhibition of outgrowth did not survive after HH29. These embryos presented with thin compact myocardium, devoid of vessels. In embryos with delayed epicardial outgrowth the phenotype was less severe, and surviving embryos were studied up to HH35. In these embryos, myocardial vascularization was poor and apoptosis in the peritruncal region at HH30 was diminished. Embryos at HH35 displayed an abnormal coronary network and absent coronary orifices. In a further set of experiments (n=10), outgrowth was inhibited in chicken embryos at HH15, followed by transplantation of a quail proepicardial organ into the pericardial cavity to rescue cardiac phenotype. These chimeras were studied at HH29 and HH35. Myocardial development was restored; however, in 3 of 4 embryos (HH35), the coronary orifices were absent. Examination of double stainings of quail-chicken chimeras revealed that EPDCs produce Fas ligand as an apoptotic inductor at sites of coronary ingrowth. In the absence of proper timing of epicardial outgrowth, myocardial development and vascularization are disturbed. Also apoptosis in the peritruncal region is diminished. During later development, this leads to defective or absent connections of the coronary system to the systemic circulation.     

Psychological distress and styles of coping in parents of children awaiting elective cardiac surgery

AIMS: We sought to assess the level of psychological distress, and the styles of coping of, parents of children with congenital heart disease. The study was based on questionnaires, which were completed, on average, four weeks, with a range from 0.1 to 22.1 weeks, prior to elective cardiac surgery or elective catheter intervention. METHODS: We used the General Health Questionnaire, and the Utrecht Coping List, to compare scores from parents of those undergoing surgery, with scores of reference groups, and with scores of the parents of those undergoing intervention. RESULTS: Overall, in comparison with our reference groups, the parents of the 75 children undergoing surgery showed elevated levels of psychological distress, manifested as anxiety, sleeplessness, and social dysfunctioning. They also demonstrated less adequate styles of coping, being, for example, less active in solving problems. With only one exception, no differences were demonstrated in parental reactions to whether cardiac surgery or catheter intervention had been planned. The mothers of the 68 patients who were to undergo cardiac surgery, however, reported greater psychological distress and manifested greater problems with coping than did the fathers. CONCLUSION: Elevated levels of psychological distress, and less adequate styles of coping, were found in the parents of patients about to undergo cardiac surgery, especially the mothers, when compared to reference groups. Future research should investigate whether these difficulties persist, and whether this will influence the emotional development of their children with congenital cardiac malformations.     

Formation of intimal cushions in the ductus arteriosus as a model for vascular intimal thickening. An immunohistochemical study of changes in extracellular matrix components.

There is a great resemblance in the sequence of events that take place in the pathological development of intimal thickening, so called arteriosclerosis and the formation of intimal cushions in both the normal ductus arteriosus (DA) and the persistent ductus arteriosus (PDA). The human DA was used as a model to study the changes in the extracellular matrix during this process with immunohistochemistry. The formation of intimal cushions was studied in 4 normal fetal DA, 4 normal mature DA and 3 persistent DA. The process of intimal thickening in the fetus starts in the second trimester of pregnancy with an accumulation of glycosaminoglycans in the subendothelial region (SER), accompanied by separation of endothelial cells from the internal elastic lamina and followed by migration of smooth muscle cells into the subendothelial region. This phenomenon was also observed in the mature DA in the neonate, indicating that cushion formation is a continuous process. Intimal cushions had also developed in the persistent DA, although they were morphologically different from the cushions found in the normal mature DA. It was remarkable that two elastic lamellae could be distinguished: one at the original site on the borderline of intimal cushion and media and the other in a subendothelial position. The endothelial cells were firmly attached to this subendothelial lamina, which was wrapped in the basal lamina components laminin and type IV collagen. The main morphological difference between the normal mature DA and the persistent DA is the close relation between endothelial cells and the subendothelial elastic lamina, suggesting an altered elastin metabolism in the PDA. PGI2 synthase was increased in the wall of both the normal and persistent DA as compared with the aorta. It may be related to a role of PGI2 in the formation of intimal cushions.     

Functional reconstitution of the NADPH-oxidase by adeno-associated virus gene transfer

Chronic granulomatous disease (CGD) comprises a heterogeneous group of inherited conditions characterized biochemically by disordered function of a unique multicomponent enzyme system present in phagocytic cells, the NADPH-oxidase. Clinically, it is characterized by recurrent bacterial and fungal infections that are relatively resistant to treatment by conventional means. Curative bone marrow transplantation has been successfully achieved in a small number of cases, but the wider application of this procedure is limited by availability of suitable donor material. Somatic gene therapy would overcome this problem, and several groups have now shown correction of the biochemical defect in hematopoietic cells by retrovirus-mediated gene transfer. However, the failure of the current generation of retroviral vectors to efficiently transduce quiescent cells greatly restricts their potential for gene transfer to pluripotent hematopoietic stem cells. Given these limitations, we have constructed vectors based on adeno-associated virus and used these to transfer a functional copy of the p47phox gene to immortalized B cells derived from patients with p47phox-deficient autosomal recessive CGD. We show stable expression of protein and restoration of NADPH-oxidase function in these cells in the absence of selection. Adeno-associated virus vectors may overcome some of the limitations of retroviral gene delivery systems and may therefore be a useful vehicle for curative gene therapy of CGD and other primary immunodeficiencies.     

Hyperplastic polyps and the risk of adenoma recurrence in the polyp prevention trial

BACKGROUND AND AIMS: Recent studies have suggested that some hyperplastic polyps may be associated with an increased risk of colorectal cancer. Prospective information on the risk of adenoma recurrence associated with hyperplastic polyps is limited. We sought to investigate whether the coexistence of hyperplastic polyps with adenomas increases the risk of adenoma recurrence. METHODS: We used unconditional logistic regression models to examine the association between baseline hyperplastic polyps and subsequent adenoma recurrence during a 3-year follow-up evaluation, among 1637 participants in the Polyp Prevention Trial. RESULTS: A total of 437 participants (26.7%) had hyperplastic polyps coexisting with adenomas at baseline. Of these, 132 (30.2%) had at least one hyperplastic polyp in the proximal colon, whereas 305 (69.8%) had only distal hyperplastic polyps. When compared with subjects without any hyperplastic polyps at baseline, there was no statistically significant association between the presence of baseline hyperplastic polyps and recurrence of any adenoma (odds ratio [OR], 1.19; 95% confidence interval [CI], 0.94-1.51) or advanced adenoma (OR, 1.25; 95% CI, 0.78-2.03). Also, there was no association between hyperplastic polyp location and adenoma recurrence (OR, 1.01; 95% CI, 0.69-1.48) for any proximal hyperplastic polyp (OR, 1.26; 95% CI, 0.96-1.65) and for distal hyperplastic polyps. CONCLUSIONS: The coexistence of hyperplastic polyps with adenomas, irrespective of location, does not confer an increased risk of adenoma recurrence beyond that of adenomas alone within 3 years of follow-up evaluation. Prospective long-term studies on adenoma recurrence risk associated with hyperplastic polyps in screening populations are needed.     

Expression of 5'-nucleotidase (CD73) related to other differentiation antigens in leukemias of B-cell lineage

Ecto-5'nucleotidase (5'NT; CD73) expression was studied with a monoclonal antibody (7G2) and a radiochemical assay and compared with the expression of other antigens in B-cell-lineage leukemias on cells from 100 leukemic patients and two cell lines. A B-cell origin was confirmed by the expression of CD19 and HLA-DR. Four stages of B-cell leukemias were defined: stage I (pro-B) as CD10-, cytoplasmic mu- (c mu- ), surface Ig- (sIg-); stage II (cALL) as CD10+/c mu-/sIg-; stage III (pre-B) as CD10+ or -/c mu+/sIg-; and stage IV (B) as CD10-/c mu-/sIg+. A linear correlation was found between immunohistochemical and radiochemical determination of 5'NT (r = .86). 5'NT expression was low in T-cell leukemias and stage I, high in stages II and III, and low again in stage IV of B-cell leukemias. 5'NT expression was not related to c mu, CD20, CD21, CD22, CD34, and terminal deoxynucleotidyl transferase (TdT) expression, but was significantly related to CD10 and inversely related to kappa/lambda expression. However, the 5'NT activity in CD10+ leukemias (stages II and III) shows a very wide range. Within the group of CD10+ leukemias no differences were detected between 5'NT+ and 5'NT- cells in their expression of other B-cell antigens. We conclude that the place of 5'NT in leukemias corresponding to early stages of B-cell development has been characterized. 5'NT is expressed in CD10+ stages and decreases before the expression of sIgs. Future studies should make clear whether a high expression of this enzyme in CD10+ stages is a normal maturation phenomenon or a malignant phenomenon.     

Intracardiac echocardiographic guidance for hemodynamic assessment in a patient with congenital abnormalities and a prosthetic aortic valve

In this case report, we present the use of intracardiac echocardiography (ICE) for guiding the cardiac catheterization and subsequent hemodynamic investigation in an unusual patient case with multiple congenital abnormalities (bicuspid aortic valve, left cervical aortic arch, two aortic coarctations) and two aortic valve replacement operations in the past. The ICE catheter (AcuNav) permitted us to accurately and safely puncture the interatrial septum and place the Swan–Ganz catheter in the left ventricle; additionally, visualization of the aortic coarctation in the ascending aorta was also achieved.     

Focal segmental necrotizing glomerulonephritis in rheumatoid arthritis

We report ten patients with rheumatoid arthritis (RA) who developed a focal segmental necrotizing glomerulonephritis (FSNGN) and extracapillary proliferation typical of vasculitic glomerulonephritis. Five patients also had extrarenal vasculitis. Renal presentation was with renal impairment (n = 9) (median creatinine 726 mumol/l, range 230- 1592 mumol/l), microscopic haematuria (n = 8) and proteinuria (n = 10). Nine patients were seropositive for rheumatoid factor and nine had bone erosions. Serum from four of five patients tested by indirect immunofluorescence was positive for antineutrophil cytoplasmic antibody (ANCA) with perinuclear staining. Only three patients had penicillamine or gold therapy. Treatment was with prednisolone and cyclophosphamide (six patients, two of whom were also plasma-exchanged), prednisolone and azathioprine (two patients) and prednisolone alone (two patients). There was a marked improvement in renal function in eight patients. Two patients with dialysis-dependent renal failure recovered renal function, although in one patient this was transient and she required further dialysis 4 months later. Two other patients progressed to dialysis at 3 months and 1 year respectively. Four patients died, one remains dialysis-dependent, and four continue to have good renal function at 5 year follow-up (median creatinine 148.5 mumol/l, range 120-193 mumol/l). One patient was lost to follow-up at 5 years. FSNGN should be considered in all patients with RA and renal impairment, proteinuria and/or microscopic haematuria. This diagnosis appears to be more likely in patients with clinical extrarenal vasculitis, bone erosions or who are seropositive. In these cases, an urgent renal biopsy is indicated.      

EB病毒LMP2A和EB病毒BZLF1融合基因反转录病毒表达载体的构建

目的:将LMP2A和BZLF1基因进行融合同时可发挥LMP2A诱导特异性CTL和BZLF1基因诱导潜伏期EBV进入裂解期复制的作用,协同杀伤EBV阳性肿瘤细胞。实验拟构建含EB病毒潜伏膜蛋白2A编码基因和即刻早期基因融合基因的反转录病毒表达载体,并筛选建立携带该基因的高滴度产毒细胞系。方法:实验于2006-08/2007-08在济宁医学院微生物教研室和青岛大学医学院微生物教研室进行。应用反转录-聚合酶链反应分别获得潜伏膜蛋白2A和即刻早期基因编码序列的cDNA,采用剪接式重叠延伸技术将两段基因通过多肽接头(Gly_4Ser)_3的DNA序列进行连接,构建融合基因Z2A。将融合基因Z2A定向插入逆转录病毒表达载体pMSCVpuro,形成重组质粒pMSCVpuro-Z2A,脂质体法将pMSCVpuro-Z2A转染反转录病毒包装细胞PT67。嘌呤霉素筛选产毒细胞克隆,扩大培养产毒细胞克隆,收获病毒进行滴度测定,RT-PCR检测产毒PT67细胞目的基因的转录表达。结果:限制性酶切、PCR及测序鉴定证实Z2A正确插入逆转录病毒表达载体,筛选获得了稳定产毒的嘌呤霉素抗性细胞克隆,收获病毒的滴度为7.8×10~6 CFU/L,且重组逆转录病毒在PT67细胞能有效转录。结论:携带Z2A基因的重组反转录病毒表达载体pMSCVpuro-Z2A构建成功,转染PT67细胞后包装出重组反转录病毒,进而筛选获得了能转录表达Z2A的产毒细胞系PT67-Z2A。     

静脉注射同种异体骨髓间充质干细胞对血管性痴呆大鼠海马区脑组织形态及微管相关蛋白2表达的影响

目的:骨髓间充质干细胞移植进入脑组织后,能否影响脑组织的形态及微管相关蛋白2的表达从而改善痴呆状态下的认知功能?观察静脉注射同种异体骨髓间充质干细胞后,血管性痴呆模型大鼠脑海马CA1区脑组织形态及微管相关蛋白2的变化。方法:实验于2004-08/2005-05在解放军第二军医大学完成。①实验动物:健康雄性SD大鼠60只,随机数字表法分为细胞移植组、模型对照组、假手术组,20只/组。②实验方法:另取20只大鼠用于体外分离、培养扩增骨髓间充质干细胞,传至第2代时加入BrdU进行标记,制备单细胞悬液,调整细胞浓度为3×109L-1。细胞移植组、模型对照组采用双侧颈总动脉结扎法建立血管性痴呆动物模型,假手术组仅暴露双侧颈总动脉但不结扎。造模后4周,细胞移植组尾静脉注射骨髓间充质干细胞悬液1mL,模型对照组注射等量磷酸盐缓冲液,假手术组不进行尾静脉注射。③实验评估:细胞移植后4周,苏木精-伊红染色检测各组大鼠脑海马CA1区脑组织形态变化,免疫荧光染色观察经BrdU标记的骨髓间充质干细胞示踪情况,免疫组织化学染色检测脑海马CA1区微管相关蛋白2的表达。结果:细胞移植组5只大鼠死亡,模型对照组3只大鼠死亡,假手术组均进入结果分析。①脑海马CA1区锥体细胞形态变化:细胞移植组和模型对照组CA1区锥体细胞较假手术组排列稀疏、紊乱,细胞肿胀、脱失,核固缩,但细胞移植组细胞排列较模型对照组规则,且细胞肿胀、脱失及核固缩较模型对照组减轻。②脑海马内骨髓间充质干细胞的示踪:细胞移植后4周,大鼠脑海马内可见被绿色荧光标记的骨髓间充质干细胞。③脑海马CA1区微管相关蛋白2的表达:与假手术组比较,细胞移植组及模型对照组脑海马CA1区锥体细胞层微管相关蛋白2阳性产物的吸光度值均明显降低(P<0.05);细胞移植组明显高于模型对照组(P<0.05)。结论:静脉注射骨髓间充质干细胞能够使血管性痴呆大鼠脑海马CA1区神经元损伤及脱失减轻,并使微管相关蛋白2表达增加。