RESUMEN
Animal models are essential to studies of infectious diseases. The use of mice to test bacterial infection has been extensively reported. However, methods applied to clinical isolates, particularly for carbapenem-resistant bacteria, must be tailored according to the infection models and bacteria used. In this study, we infected 6-week-old female BALB/c mice intraperitoneally with different strains of resistant bacteria plus 3% hog gastric mucin. This method was found to be efficient and readily applicable for investigation of carbapenem-resisant Gram-negative pathogens (e.g., Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii) detected in Korea.
Asunto(s)
Animales , Femenino , Humanos , Ratones , Acinetobacter , Bacterias , Infecciones Bacterianas , Enfermedades Transmisibles , Escherichia coli , Mucinas Gástricas , Bacterias Gramnegativas , Klebsiella pneumoniae , Corea (Geográfico) , Métodos , Modelos Animales , Peritonitis , Pseudomonas aeruginosaRESUMEN
OBJECTIVE To construct the lentiviral vector system expressing MDR1 small interference RNA, and identify reversal efficiency of multidrug resistant phenotype in the human laryngeal cancer multidrug resistance cell lines (LSC-1/TAX). METHODS Three target sequences of oligonucleotides were selected according to MDR-1 gene sequence, the complementary DNA contained both sense and antisense strands were designed and synthesized. After the oligonucleotides were inserted into the plasmid expression system pLVTHM, the plasmid was cotransfected along with pCMV-dR8.74 and pMD2G into 293T cell lines to package lentiviral particles. Interference efficiency of the lentiviral vector system expressing MDR1 small interference RNA was determined by RT-PCR, real time PCR and Western Blot in the human laryngeal cancer multidrug resistance cell lines (LSC-1/TAX), drug resistance was measured by MTT assay after interference. RESULTS It was confirmed by digestion and sequencing that lentiviral vector had the correct structure and could express the GFP and siRNA. The functional titer of concentrated virus was more than 1?108TU/ml. The vectors expressing 3 target sequences can infect LSC-1/TAX, and the third vector has the best interference efficiency. CONCLUSION The lentiviral vector system expres-sing MDR1 siRNA has been constructed, which is necessary to reverse multidrug resistance phenotype in the human laryngeal cancer multidrug resistance cell lines
RESUMEN
Objective To investigate whether the protein kinase C inhibitor can promote the apopto- sis of multidrug resistance tumor cell lines which are induced by chemotherapy drugs.Methods Choose the KB/S(oral squamous cancer cell line)and KB/VCR(its multidrug resistant cell line)to compare the Adri- amycin-induced apoptosis with or without staurospolin(protein kinase C inhibitor).The apoptosis is stained with acridine orange,tested by flow cytometry,and approved by electron microscope.Results 36 hours after the treatment with 0.04 ?g/ml adriamycin,apoptotic cells of KB/S are 96.68%,and after 48 hours,the apop- totic cells of KB/VCR are 64.99%.When the concentration of adriamycin are augmented to 0.4?g/ml and 2.0?g/ml,the apoptotic cells of KB/VCR are 69.74% and 37.18% respectively.When treated with stau- rospolin together,the apoptotic cells of KB/VCR increased to 72.58%(?~2=4.5,P0.05)respectively.These results were testified by electron microscope and acridine orange-stain.Conclu- sion The resistance to apoptosis may be one of the mechanisms of multidrug resistance and the protein ki- nase C inhibitor may reverse this resistance by promoting the apoptosis of multidrug resistance tumor cells.