Biphasic responses of bone to parathyroid hormone-related protein-141 in vitro / 重庆医科大学学报

Objective:To determine the role of PTHrP in new bone formation and bone destruction and the mechanisms involved.Methods:LCC15-MB breast cancer cells were transfected with full-length PTHrP-141 cDNA,and the conditioned medium was collected and cultured with mouse calvarial bones in an in vitro organ culture system.The effects of 1PTHrP-141 on new bone formation and bone destruction were examined by histological examination.Results:PTHrP produced from transfected breast cancer cells induced new bone formation at lower doses and bone resorption at higher concentrations.Conclusion:These results provide direct evidence that PTHrP plays a biphasic role in bone remodeling depending on the concentration administered.

Distribution and antibacterial resistance of pathogens of ventilator-associated pneumonia in general intensive care unit / 西安交通大学学报(医学版)

Objective To investigate the distribution and drug resistance of pathogens of ventilator-associated pneumonia(VAP) in general intensive care unit(ICU).Methods Statistical methods were used to analyze retrospectively the data of pathogens and drug resistance of VAP in general ICU from 2004 to 2006.Results Totally 347 pathogens were isolated from deep-part secretion of lower respiratory tracts of 302 VAP in general ICU.The main pathogens included Pseudomonas aeruginosa(32.3%),Acinetobacter baumanii(31.1%),Staphylococcus aurous(16.7%),Klebsiella(7.5%) and Coagulase-negative Staphylococci(6.1%).Gram-negative bacillus showed a high resistance to piperacillin and Cefotaxime but high susceptibility to carbapenems and the enzyme inhibitor antibiotics.Gram-positive coccobacteria showed a high resistance to Penicillin,Clindamycin and Erythromycin but high susceptibility to Vancomycin and Quinolone.Conclusion Gram-negative bacillus was the main pathogen of VAP in general ICU,multidrug resistance was serious.The rate of methicillin-resistant staphylococcus aurous(MRSA) and methicillin-resistant coagulase-negative staphylococci(MRCNS) was high,with serious drug resistance.According to the data of the bacteria pathogen and antibiotics susceptibity,we can select antibiotics reasonably to control the infection and delay the emergency of new drug-resistant bacteria.