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Peptide antibiotics are small peptides encoded by organism genomic DNA. They are recognized to play important roles in the innate host defense of most living organisms. The growing resistance of bacteria to conventional antibiotics and the need for discovery of new antibiotics have stimulated great interest in the development of peptide antibiotics as human therapeutics. However, preparation of peptide antibiotics at a large scale is a great challenge in developing these commercial products. In this study, tandem repeat multimers of peptide antibiotic hPAB-beta were designed and the recombinant plasmids containing one to eight copies of hPAB-beta gene were generated. Eight genetic engineered bacteria harboring pQE-hPAB-beta1-8 recombinant were able to express the repetitive hPAB-beta multimers of interest in inclusion bodies, respectively. The expressed proteins could reach 2.6-28% of the total proteins. The hPAB-beta trimer construct was selected out for the subsequent study based on its higher expression level (27.8%), which yields in wet cell weights (3.15+/-0.45 g/l) and the fusion protein inclusion bodies was able to completely dissolve in 8 M urea. The tandem trimers could easily be captured by Ni-NTA affinity chromatography and cleaved into monomers by hydroxylamine. Then, the monomer hPAB-beta of interest was purified to 95% homogeneity by reverse phase chromatography and gel filtration. The final yield of purified recombinant monomer hPAB-beta was 680+/-12 mg/100 g wet cells. The minimum inhibitory concentrations (MICs) of the purified recombinant hPAB-beta against type or clinical strains of microorganisms were about 31-250 microg/ml and these results showed that the recombinant hPAB-beta could retain its bioactivity.

Objective: To summarize the experience in surgical treatment of De Bakey type III aortic dissection and discuss the operative indications, techniques, and methods for spinal cord protection., Methods: From January 1994 to January 2000, 49 patients with De Bakey type III aortic dissection were operated on. Of these patients, 35 were subjected to partial thoratical aorta replacement, 4 partial thoratical aorta replacement and plasty, 8 total thoratical aorta replacement, and 2 thoracoabdominal aorta replacement. In the 35 patients, the operations were performed by using the technique which preserved blood was transfused back by pump via the femoral artery., Results: Hospital mortality in this group was 6.1% (3/49). Eight patients received emergence operation, and 1 patient died. Paraparesis developed in one patient (2.0%). Other complications included re-exploration for bleeding in 3 patients, and wound infection in 5., Conclusions: The rate of mortality and complication is high in patients with De Bakey type III aortic dissection. Appropriate operative techniques and methods of spinal cord protection are essential to resolve this problem.

Background: We conducted a randomized study to determine whether any of three chemotherapy regimens was superior to cisplatin and paclitaxel in patients with advanced non-small-cell lung cancer., Methods: A total of 1207 patients with advanced non-small-cell lung cancer were randomly assigned to a reference regimen of cisplatin and paclitaxel or to one of three experimental regimens: cisplatin and gemcitabine, cisplatin and docetaxel, or carboplatin and paclitaxel., Results: The response rate for all 1155 eligible patients was 19 percent, with a median survival of 7.9 months (95 percent confidence interval, 7.3 to 8.5), a 1-year survival rate of 33 percent (95 percent confidence interval, 30 to 36 percent), and a 2-year survival rate of 11 percent (95 percent confidence interval, 8 to 12 percent). The response rate and survival did not differ significantly between patients assigned to receive cisplatin and paclitaxel and those assigned to receive any of the three experimental regimens. Treatment with cisplatin and gemcitabine was associated with a significantly longer time to the progression of disease than was treatment with cisplatin and paclitaxel but was more likely to cause grade 3, 4, or 5 renal toxicity (in 9 percent of patients, vs. 3 percent of those treated with cisplatin plus paclitaxel). Patients with a performance status of 2 had a significantly lower rate of survival than did those with a performance status of 0 or 1., Conclusions: None of four chemotherapy regimens offered a significant advantage over the others in the treatment of advanced non-small-cell lung cancer.