Comparison of primary coronary artery bypass surgery in a British Indo-Asian and white Caucasian population.

AIM: To compare the clinical characteristics, at the time of admission and after coronary revascularization by bypass surgery, among British patients of Indo-Asian and white Caucasian descent. METHOD: One hundred and ninety-four pairs of patients admitted between November 1994 and January 1997 were matched for age (within 3 years), sex and date of admission (within 3 months). Their clinical characteristics at the time of admission for coronary artery bypass grafting surgery, and the incidence of hospital morbidity, hospital mortality and length of stay in the intensive therapy unit or hospital following coronary artery bypass grafting were determined. RESULTS: A higher proportion of Indo-Asian patients underwent coronary revascularization on a non-elective basis (43% vs 32% white Caucasian patients, P =0.018), had a higher prevalence of diabetes (39% vs 12%, P =0.0001), a lower prevalence of smoking (36% vs 80%, P =0.0001) and a lower rate of previous myocardial infarction (47% vs 62%, P =0.012). As regards revascularization, although there was no significant difference in the number of vessels revascularized, there was a lower use of the arterial conduit (internal mammary artery) in the Indo-Asian patients (72% vs 81%, P =0.028) particularly for those undergoing emergency/urgent surgery (59% vs 72%, P =0.001) and with a previous myocardial infarction (65% vs 81%;P =0.01) when compared with their white Caucasian counterparts. Following surgery there were no differences in the types of support required for vital functions. There was no significant difference in the proportion of major post-operative complications, that is, haemorrhage, cerebrovascular accident, renal failure requiring dialysis or respiratory failure. Similarly, there were no differences in the length of intensive therapy unit stay (median stay 1 day vs 1 day, P =0.4) and hospital stay following surgery (median stay 6 days vs 6 days, P =0.5) between the two groups. Although there was a trend towards a higher in-hospital (30 day) mortality (6.7% [95% confidence intervals CI 3.18-10.21] vs 2.6% [CI 0.35-4.9;P =0.0618]), in Indo-Asians compared to white Caucasians this trend disappeared when patients in the two groups undergoing non-elective surgery only were compared (9% vs 7%;P =0.7). CONCLUSIONS: A higher proportion of Indo-Asians underwent non-elective coronary revascularization, with a significantly lower use of the arterial conduit and a relatively higher in-hospital mortality. Following coronary revascularization the medical management, length of stay and hospital morbidity in Indo-Asian patients was no different from that of their white Caucasian counterparts. This is despite a perceived poorer outcome in Indo-Asians compared to white Caucasians.     

光谱核型分析联合微阵列比较基因组杂交诊断15号环状染色体综合征

目的 探讨联合应用光谱核型分析技术(spectral karyotyping,SKY)和微阵列比较基因组杂交技术(microarray-based comparative genomic hybridization,array-CGH)在诊断复杂疑难的环状染色体畸变中的价值.方法 对1例常规G显带染色体核型分析疑诊为46,XY,r(15)?的8岁男性生长发育迟缓患儿依次应用SKY及array-CGH技术常规进行制片杂交,并通过相应的显微摄像系统和计算机软件分析结果.结果 SKY技术明确了该患儿环状染色体来源于15号染色体,array-CGH技术明确患儿15q26.3末端存在约594 kb的缺失,染色体基因位点编码范围为99689349-100282878.结论 联合应用现代分子细胞遗传学技术可以从细胞到分子水平精确诊断复杂疑难的环状染色体病例,是常规染色体核型分析的有益补充,也有利于细胞遗传学向分子水平深入.     

Initial experience on rifampin and pyrazinamide vs isoniazid in the treatment of latent tuberculosis infection among patients with silicosis in Hong Kong

OBJECTIVE: To compare the adverse effects and treatment adherence between 2 months of rifampin plus pyrazinamide (2RZ) and 6 months of isoniazid (6H). BACKGROUND: Patients with silicosis in Hong Kong are at high risk of acquiring tuberculosis. A previous study showed that treatment with 6H reduced the risk of silico-tuberculosis by one half. METHOD: Patients with silicosis and a Mantoux skin test reaction > or =10 mm were randomized to receive either 2RZ or 6H daily. Liver function testing was done monthly during the initial 2 months. The adverse effects and treatment adherence were compared between the two regimens. RESULTS: Forty patients (mean age, 61.6 +/- 9.1 years) and 36 patients (mean age, 57.6 +/- 9.7 years) were randomized to the 2RZ and 6H arms, respectively (p > 0.05) [+/- SD]. Baseline characteristics were comparable. Nineteen patients in the 2RZ arm had peak alanine transaminase (ALT) levels > 1.5 times the upper limit of normal (ULN) in comparison with only five study subjects of the 6H arm (47.5% vs 13.9%, p < 0.01). Fourteen patients (35%) in the 2RZ arm and 1 patient (2.8%) in the 6H arm had peak ALT levels more than five times the ULN (p < 0.001). Only seven patients had symptoms suggestive of hepatitis; none of the patients had jaundice. All recovered after withholding treatment. In the 2RZ study arm, none of the baseline characteristics predicted hepatotoxicity. Other adverse effects were generally mild and comparable between both study arms. Treatment was stopped prematurely in 45% and 36.1% of patients in the 2RZ and 6H arms, respectively (p = 0.43). The main reasons were hepatotoxicity for the 2RZ arm and voluntary withdrawal after experiencing other minor adverse effects for the 6H arm. CONCLUSION: A higher incidence of hepatotoxicity was associated with rifampin plus pyrazinamide than isoniazid in the treatment of latent tuberculosis infection among patients with silicosis in Hong Kong.     

A simple noninvasive index can predict both significant fibrosis and cirrhosis in patients with chronic hepatitis C

Information on the stage of liver fibrosis is essential in managing chronic hepatitis C (CHC) patients. However, most models for predicting liver fibrosis are complicated and separate formulas are needed to predict significant fibrosis and cirrhosis. The aim of our study was to construct one simple model consisting of routine laboratory data to predict both significant fibrosis and cirrhosis among patients with CHC. Consecutive treatment-naive CHC patients who underwent liver biopsy over a 25-month period were divided into 2 sequential cohorts: training set (n = 192) and validation set (n = 78). The best model for predicting both significant fibrosis (Ishak score > or = 3) and cirrhosis in the training set included platelets, aspartate aminotransferase (AST), and alkaline phosphatase with an area under ROC curves (AUC) of 0.82 and 0.92, respectively. A novel index, AST to platelet ratio index (APRI), was developed to amplify the opposing effects of liver fibrosis on AST and platelet count. The AUC of APRI for predicting significant fibrosis and cirrhosis were 0.80 and 0.89, respectively, in the training set. Using optimized cut-off values, significant fibrosis could be predicted accurately in 51% and cirrhosis in 81% of patients. The AUC of APRI for predicting significant fibrosis and cirrhosis in the validation set were 0.88 and 0.94, respectively. In conclusion, our study showed that a simple index using readily available laboratory results can identify CHC patients with significant fibrosis and cirrhosis with a high degree of accuracy. Application of this index may decrease the need for staging liver biopsy specimens among CHC patients.     

Optimal timing of the Ross procedure in the management of chronic aortic incompetence in the young

The appropriate timing of intervention in patients with chronic aortic incompetence allows recovery of ventricular function. We sought to determine the optimal timing of the Ross procedure for chronic aortic incompetence in young patients. We retrospectively analysed case notes, and measured pre- and postoperative echocardiographic indexes of left ventricular function, in patients who had undergone the Ross procedure for chronic aortic incompetence. METHODS AND RESULTS: We found 21 patients with preoperative and postoperative data suitable for analysis. Their age at operation ranged from 5.6 to 26 years, with a median of 13.8 years, and the duration of follow-up was from 0.5 to 6.8 years, with a median of 2.4 years. The preoperative left ventricular end-diastolic dimension was converted to a z-score, and this was used as a threshold to divide the population. Using the threshold of a preoperative left ventricular z-score of more than 3 to divide the population did not show any difference in postoperative parameters of left ventricular function. Significant differences were found postoperatively, however, in both the left ventricular z-score and the ratio of left ventricular end-diastolic radius to posterior wall thickness in diastole, with a cutoff preoperative threshold z-score greater than 4. CONCLUSION: The increase in the ratio of left ventricular end-diastolic radius to the thickness of the posterior wall in diastole would suggest that there is disruption of left ventricular short axis architecture and myocardial contractile function when intervention is postponed. The significantly larger left ventricular dimension at end-diastole, despite the reduction in volume loading post surgery, may also demonstrate irreversible structural changes. Our data would suggest that recovery of left ventricular function is less likely when the left ventricular z-score has reached the value of 4, and that, ideally, intervention should be performed when the z-score approaches or exceeds 3.     

Type 1 Fimbriation and Its Phase Switching in Diarrheagenic Escherichia coli Strains

Type 1 fimbriae can be expressed by most Escherichia coli strains and mediate mannose-sensitive (MS) adherence to mammalian epithelial cells. However, the role of type 1 fimbriae in enteric pathogenesis has been unclear. Expression of type 1 fimbriae in E. coli is phase variable and is associated with the inversion of a short DNA element (fim switch). Forty-six strains of diarrheagenic E. coli were examined for the expression of type 1 fimbriae. Only four of these strains were originally type 1 fimbriated. Seventeen strains, originally nonfimbriated, expressed type 1 fimbriae in association with off-to-on inversion of the fim switch, after serial passages in static culture. The switching frequencies of these strains, from fimbriate to nonfimbriate, were greater than that of the laboratory strain E. coli K-12. None of the 16 strains of serovar O157:H7 or O157:H⁻ expressed type 1 fimbriae after serial passages in static culture. The nucleotide sequence analysis of the fim switch region revealed that all of the O157:H7 and O157:H⁻ strains had a 16-bp deletion in the invertible element, and the fim switch was locked in the “off” orientation. The results suggest that expression of type 1 fimbriae may be regulated differently in different E. coli pathogens causing enteric infections.     

Characteristics of Money Management Strategies in Urban China and Its Impact on Women's Marital Quality

目的:探讨城市家庭管钱方式的特点及其对女性婚姻质量的影响.方法:采用目的抽样法对北京市区752位已婚女性和郊区1088位已婚女性进行调查.结果:共同管理是我国城市家庭使用最多的管钱方式,其次为妻子管理和各自管理,丈夫管理的方式则最少被使用.使用共同管理方式的女性报告的婚姻幸福感和夫妻互动程度最高,婚姻冲突、婚姻问题和离婚意向最低.而使用各自管理方式的女性报告的婚姻幸福感和夫妻互动程度最低,婚姻冲突、婚姻问题和离婚意向最高.使用妻子管理和丈夫管理方式的女性在婚姻质量的各个维度上都处于中间状态.结论:家庭管钱方式对女性的婚姻质量有影响.     

Delineation of a deletion region critical for corpus callosal abnormalities in chromosome 1q43-q44

Submicroscopic deletions involving chromosome 1q43-q44 result in cognitive impairment, microcephaly, growth restriction, dysmorphic features, and variable involvement of other organ systems. A consistently observed feature in patients with this deletion are the corpus callosal abnormalities (CCAs), ranging from thinning and hypoplasia to complete agenesis. Previous studies attempting to delineate the critical region for CCAs have yielded inconsistent results. We conducted a detailed clinical and molecular characterization of seven patients with deletions of chromosome 1q43-q44. Using array comparative genomic hybridization, we mapped the size, extent, and genomic content of these deletions. Four patients had CCAs, and shared the smallest region of overlap that contains only three protein coding genes, CEP170, SDCCAG8, and ZNF238. One patient with a small deletion involving SDCCAG8 and AKT3, and another patient with an intragenic deletion of AKT3 did not have any CCA, implying that the loss of these two genes is unlikely to be the cause of CCA. CEP170 is expressed extensively in the brain, and encodes for a protein that is a component of the centrosomal complex. ZNF238 is involved in control of neuronal progenitor cells and survival of cortical neurons. Our results rule out the involvement of AKT3, and implicate CEP170 and/or ZNF238 as novel genes causative for CCA in patients with a terminal 1q deletion.     

Relationships Between Femoral Strength Evaluated by Nonlinear Finite Element Analysis and BMD, Material Distribution and Geometric Morphology

Precise quantification of femur strength and accurate assessment of hip fracture risk would help physicians to identify individuals with high risk and encourage them to take preventive interventions. A major contributing factor of hip fracture is the reduction of hip strength, determined by the bone quality. Bone mineral density (BMD) alone cannot determine bone strength accurately. In this paper, subject-specific quantitative computer tomography (QCT) image-based finite element analyses were conducted to identify the quantitative relationships between femoral strength and BMD, material distribution and geometric morphology. Sixty-six subjects with QCT data of hip region were selected from the MrOS cohorts in Hong Kong. Subject-specific nonlinear finite element models were developed to predict strengths of proximal femurs. The models took non-linear elasto-plasticity and heterogeneity of bone tissues into consideration and derived bone strengths with proper bone failure criteria. From finite element analysis (FEA), relationships between femoral strength and BMD, material distribution, and geometric parameters were determined. Results showed that FEA-predicted femoral strength was highly correlated with BMD, material distribution, height, weight, diameters of femoral head (HD), and femoral neck (ND), as well as the moment arm for femoral neck bending-offset (OFF). Through principal components analysis, three independent principal components (PCs) were extracted. PC1 was the component of bone material quality. PC2 included height, weight, HD, and ND. PC3 mainly represented OFF. Multivariate linear regression showed that the PCs were strongly predictive of the FEA-predicted strength. This study provided quantitative information regarding the contributing factors of proximal femur strength and showed that such a biomechanical approach may have clinical potential in noninvasive assessment of hip fracture risk.     

Tumor tropism of intravenously injected human-induced pluripotent stem cell-derived neural stem cells and their gene therapy application in a metastatic breast cancer model

Human pluripotent stem cells can serve as an accessible and reliable source for the generation of functional human cells for medical therapies. In this study, we used a conventional lentiviral transduction method to derive human-induced pluripotent stem (iPS) cells from primary human fibroblasts and then generated neural stem cells (NSCs) from the iPS cells. Using a dual-color whole-body imaging technology, we demonstrated that after tail vein injection, these human NSCs displayed a robust migratory capacity outside the central nervous system in both immunodeficient and immunocompetent mice and homed in on established orthotopic 4T1 mouse mammary tumors. To investigate whether the iPS cell-derived NSCs can be used as a cellular delivery vehicle for cancer gene therapy, the cells were transduced with a baculoviral vector containing the herpes simplex virus thymidine kinase suicide gene and injected through tail vein into 4T1 tumor-bearing mice. The transduced NSCs were effective in inhibiting the growth of the orthotopic 4T1 breast tumor and the metastatic spread of the cancer cells in the presence of ganciclovir, leading to prolonged survival of the tumor-bearing mice. The use of iPS cell-derived NSCs for cancer gene therapy bypasses the sensitive ethical issue surrounding the use of cells derived from human fetal tissues or human embryonic stem cells. This approach may also help to overcome problems associated with allogeneic transplantation of other types of human NSCs.