Molecular Cloning and Preliminary Analysis of a Fragile Site Associated Gene

Objective To analyze the molecular coining of a fragile site-associated gene. Methods Genomic Chinese hamster ovary （CHO） DNA library was constructed using high molecular weight CHO DNA partially digested with MboI restriction enzyme from cultured CHO cells. Screening of genomic DNA library followed the established procedures. Genomic CHO in the positive clones was sequenced. Appropriate primers were designed for the reverse transcriptase-polymerase chain reactions （RT-PCR）. The RT-PCR products were cloned into a pCRII TOPO vector and confirmed by DNA sequencing. Antibodies were prepared using synthetic peptides as antigens by immunizing the rabbits. Immunohistochemical analyses were performed to evaluate the expression of the novel gene in different tissues. Results To investigate the molecular mechanism underlying the initial events of mdrla amplification, we cloned lq31 fragile site DNA. Strikingly, we found that this fragile site contained a novel gene which was designated as a fragile site-associated （FSA） gene. FSA encoded an unusually large mRNA of - 16 kb. Full-length human FSA eDNA was cloned. FSA mRNA was expressed in many cultured cells and tissue types. Immunohistochemical analyses also revealed an expression pattern of the encoded proteins in postmitotic, well-differentiated epithelial compartments of many organs, including colon, mammary glands, ovary, prostate, and bladder. Conclusion FSA plays an important role in regulating mammalian epithelial cell growth and differentiation.

Severe coronary artery disease in Chinese patients with abdominal aortic aneurysm： prevalence and impact on operative mortality

Background Little is known about the prognosis of coronary artery disease （CAD） in Chinese patients with abdominal aortic aneurysm （AAA）. The aim of this study was to evaluate the predictors of in-hospital all-cause mortality of severe CAD in Chinese patients who were hospitalized for AAAs. Methods From January 2003 to August 2009, 368 patients were operated on for AAAs. The clinical characteristics were retrospectively collected. The primary outcome was the in-hospital all-cause mortality. The clinical risk factors were subjected to a multivariate analysis to determine the predictors of in-hospital all-cause mortality. Results During their hospitalization, 23% （85/368） of the patients underwent coronary angiography, which revealed significant lesions in 93% （79/85） of the patients. In 25 cases, coronary artery bypass grafting （CABG） was performed before the AAA repair and in 16 cases of percutaneous coronary intervention （PCI） was performed. Ten patients with AAA alone died before discharge, and eight patients diagnosed with AAA combined with CAD died. There was no statistical difference in the postoperative death between the two groups. The logistic analysis showed that age 〉70 years and CAD （vessels ≥2） were the significant factors in predicting the adverse clinical outcome. Conclusions The prevalence of severe CAD in Chinese patients with AAAs seemed lower than those that were reported. Myocardial evaluation and subsequent revascularization before AAA surgery could improve the clinical outcome for these patients who have severe CAD.