Design, Synthesis and Antimicrobial Evaluation of Novel Benzimidazoleincorporated Naphthalimide Derivatives as Salmonella typhimurium DNA Intercalators, and Combination Researches.

OBJECTIVE: A series of novel benzimidazole-incorporated naphthalimide derivatives were designed and prepared in an effort to overcome the increasing antibiotic resistance. METHODS: The target novel benzimidazole-incorporated naphthalimide derivatives were synthesized from commercial 4-bromo-1,8-naphthalic anhydride and o-phenylene diamine by aminolysis, Nalkylation and so on. The antimicrobial activity of the synthesized compounds was evaluated in vitro by a two-fold serial dilution technique. The interaction of compound 10g with Salmonella typhimurium DNA was studied using UV-vis spectroscopic methods. RESULTS: Compound 10g bearing a 2,4-dichlorobenzyl moiety exhibited the best antimicrobial activities in this series relatively; especially, it exhibited comparable activity against Salmonella typhimurium in comparison with the reference drug Norfloxacin (MIC = 4 µg/mL). Further research showed that compound 10g could effectively intercalate into the Salmonella typhimurium DNA to form the 10g-DNA complex, which might correlate with the inhibitory activity. Molecular docking results demonstrated that naphthalimide compound 10g could interact with base-pairs of DNA hexamer duplex by π-π stacking. Additionally, the combination of the strong active compound with clinical drugs exhibited better antimicrobial efficiency with less dosage and broader antimicrobial spectrum than the separate use of them alone. Notably, these combined systems were more sensitive to Fluconazole-insensitive M. ruber. CONCLUSION: This work provides a promising starting point to optimize the structures of benzimidazole- incorporated naphthalimide derivatives as potent antimicrobial agents.

[RET gene cys 634 trp mutation in a multiple endocrine neoplasia type 2A kindred].

OBJECTIVE: To identify the genotype of RET gene in one multiple endocrine neoplasia type 2A (MEN2A) kindred. METHODS: Genome DNA was extracted from peripheral blood leucocytes. The DNA sequence of gel-purified polymerase chain reaction (PCR) products was determined with the previously reported 6 pairs of primers of PCR amplification of 10, 11, 13, 14, 15, and 16 exons of RETgene. RESULTS: No abnormalities were found in exon 10, 13, 14, 15, and 16. C to G replacement in nucleotide 14 996 of exon 11 was identified in DNA samples obtained from both peripheral blood of 2 affected brothers. This missense point mutation arisen in heterozygosity and caused a substitution of Cys to Trp residue at codon 634 ( Cys 634 Trp) in RET protein. CONCLUSION: The genotype of the family is identified as Cys 634 Trp substitution of RET gene.

[Assessment of preoperative localization techniques for patients with primary hyperparathyroidism].

OBJECTIVE: To evaluate the sensitivity and usefulness of 99mTc-sestamibi scintigraphy (SS) and neck ultrasonography (US) as preoperative localization procedures in patients with primary hyperparathyroidism (pHPT). METHODS: 160 patients with proved pHPT in Peking Union Medical College Hospital from June 1983 to June 2002 were studied. There were 107 women(66.9%) and 53 men (33.1%), with a mean age of 38.9 years (10-73 years). 100 patients were underwent SS and 148 patients were underwent US prior to surgery, and the results were compared with operative and histological findings. RESULTS: The sensitivity of SS and US in localization of the enlarged parathyroid glands was 94.0% and 85.1% respectively, and the positive predictive value of SS and US was 100% and 89.1% respectively, the overall sensitivity was 98.9% by combination of SS and US. In solitary parathyroid adenomas group (n = 145), the sensitivity of SS and US was 93.3% and 84.7% respectively; There was no significant difference (P = 0.428) in sensitivity of SS between the parathyroid glands correctly identified and undetected in classical neck location as compared with ectopic parathyroid glands, whereas significantly (P = 0.026) influenced by the US sensitivity. CONCLUSIONS: Different sensitivity exit between SS and VS in preoperative localization in patients with pHPT undergoing parathyroidectomy. The combined use of SS and US could increase the sensitivity of localization technique. Ectopic parathyroid had no influence on the sensitivity of 99mTc-MIBI scanning, but decreased the sensitivity of ultrasonography. The size of parathyroid tumors had effects on the sensitivity of ultrasonography. Otherwise, various conditions causing SS false negative were observed. Some interfere factors should be excluded when SS negative results were encountered in clinical practice.