ABSTRACT
Objective@#To investigate the pathogen spectrum distribution and drug resistance of febrile neutropenic patients with hematological diseases in Shanghai.@*Methods@#A retrospective study was conducted on the clinical isolates from the febrile neutropenic patients hospitalized in the departments of hematology in 12 general hospitals in Shanghai from January 2012 to December 2014. The drug susceptibility test was carried out by Kirby-Bauer method. WHONET 5.6 software was used to analyze pathogenic bacteria and drug susceptibility data.@*Results@#A total of 1 260 clinical isolates were collected from the febrile neutropenic patients. Gram-positive bacteria accounted for 33.3% and Gram-negative bacteria accounted for 66.7%. Klebsiella pneumoniae (12.5%) , Stenotrophomonas maltophilia (9.5%) , Escherichia coli (9.1%) , Pseudomonas aeruginosa (8.7%) , Acinetobacter baumannii (6.6%) , Staphylococcus aureus (5.6%) and Enterococcus faecium (5.0%) were ranked in the first 7 of all pathogens. In the respiratory tract secretions specimens, non-fermented strains accounted for 56.2%. Stenotrophomonas maltophilia accounted for 15.2%. Enterobacteriaceae and coagulase-negative Staphylococci accounted for 42.3% (104/246) and 32.6% (85/246) respectively in blood samples. Enterobacteriaceae and Enterococcus bacteria accounted for 39.4% (76/193) and 28.5% (55/193) respectively in pus specimens. The detection rates of methicillin resistant Staphylococcus aureus (MRSA) and methicillin resistant coagulase negative Staphylococci (MRCNS) were 54.3% and 82.5%, respectively. Staphylococcus bacterial strain was not found to be resistant to linezolid, vancomycin and teicoplanin. The detection rate of Enterococcus vancomycin-resistant strains was 8.9%. Enterococcus was not detected resistance to oxazolidinone strains. Enterobacteriaceae bacteria were highly sensitive to carbapenems. The resistance rate of Pseudomonas aeruginosa to imipenem and meropenem was 34.1% and 15.8%, respectively. Stenotrophomonas maltophilia was more sensitive to minocycline hydrochloride, levofloxacin and sulfamethoxazole. The resistance rate of Acinetobacter baumannii only to cefoperazone-sulbactam was less than 10.0%. The antibiotic resistance rate of Klebsiella pneumoniae, Stenotrophomonas maltophilia, Pseudomonas aeruginosa and Acinetobacter baumanii to most of common antibiotics was lower than that of the CHINET surveillance.@*Conclusions@#The pathogenic strain distribution in common infection sites of febrile neutropenic patients was characterized. Bacterial resistance surveillance was better than the CHINET nationwide large sample surveillance in China.
ABSTRACT
Background and purpose:Although bortezomib has become one of the major therapeutic agents against newly diagnosed or relapsed multiple myeloma (MM), there are some patients who become resistant to bor-tezomib and then relapse, emerging as a major obstacle to long-term survival of MM patients. It has been found that elevation of intracellular cyclic adenosine monophosphate (cAMP) levels could induce cell cycle arrest and apoptosis in MM cells,which has become an interesting approach to MM therapy. This study aimed to investigate possible effects of forskolin combined with bortezomib on bortezomib-resistant myeloma cells and further explore its mechanisms. Methods:The bortezomib-resistant MM cell lines H929-R and primary cells from patients who do not respond to bortezomib were used asin vitro models. The inlfuences of bortezomib and/or forskolin on MM cells were evaluated through cellular morphology, changes of cell distribution and apoptotic rate. Meanwhile, lfow cytometry analysis was used to detect mitochondrial transmembrane potential (ΔΨm) and the expression levels of apoptosis regulators in these cells before and after the treatment were detected by Western blot.Results:Bortezomib (20 nmol/L) synergized with forskolin (50nmol/L) to induce apoptosis of H929-R cells and bortezomib-resistant primary cells. In addition, borte-zomib synergized with forskolin to induce collapse of mitochondrial transmembrane and facilitate the degradation of anti-apoptosis proteins including Bcl-2 and Mcl-1.Conclusion:Bortezomib could synergize with forskolin to induce apoptosis in bortezomib-resistant MM cells.