[Immunomodulatory effects of Astragalus polysaccharide in diabetic mice].

OBJECTIVE: To study the immunomodulatory effects of Astragalus polysaccharide (APS) in type 1 diabetic mice. METHODS: A mouse model of type 1 diabetes mellitus was established by intraperitoneal injection of multiple low dose streptozotocin (MLD-STZ). The diabetic mice were intraperitoneally administered 100, 200, 400 mg/kg APS or 1 ml normal saline (NS) every day respectively, then the diabetic mice were sacrificed after 15 or 30 days of treatment. The effect of APS on insulitis was determined via pancreatic histological analysis. Serum insulin autoantibody (IAA) levels were measured by radio-immunoassay (RIA). Proliferation ability of splenocytes to concanavalin A was tested by using [(3)H] thymidine incorporation assay. The levels of cytokine interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) secreted by splenocytes were determined by enzyme linked immunosorbent assay (ELISA) method, and the expression of peroxisome proliferator-activated receptor gamma (PPARgamma) in spleens was characterized using Western-blot analysis. RESULTS: Attenuated insulitis, down-regulation of the serum IAA levels and Th1/Th2 cytokine ratio, decrease of the proliferation ability of splenocytes to concanavalin A, and up-regulation of the PPARgamma levels in spleens showed a significant time- and dose-dependent response to APS treatment as compared with the NS-treated group. CONCLUSION: APS possesses immunotherapeutic effects on mice with type 1 diabetes mellitus through improving the cell- and humoral-mediated immunity.

Combination carbapenem-sulbactam therapy for critically ill patients with multidrug-resistant Acinetobacter baumannii bacteremia: four case reports and an in vitro combination synergy study.

Infections caused by multidrug-resistant Acinetobacter baumannii have become a therapeutic challenge for clinicians worldwide. Although colistin and tigecycline have been successful in treating patients with these infections, these agents are not available on a worldwide basis. We describe four critically ill patients in Taiwan who were diagnosed with multidrug-resistant Acinetobacter baumannii bacteremia. All bacterial isolates from these patients were resistant to commonly available antibiotics, including carbapenems and sulbactam; however, combination therapy with a carbapenem and sulbactam led to favorable clinical outcomes in all four patients. We also conducted an in vitro study using isolates from these patients that showed that this drug combination had a synergistic effect with enhanced antibacterial activity against the isolates. Thus, a carbapenem-sulbactam combination may be a therapeutic alternative for multidrug-resistant Acinetobacter baumannii bacteremia in countries where colistin and tigecycline are not available for clinical use.

A new therapeutic challenge for old pathogens: community-acquired invasive infections caused by ceftriaxone- and ciprofloxacin-resistant Salmonella enterica serotype choleraesuis.

Recently, antimicrobial resistance among nontyphoid Salmonella serotypes has been increasingly recognized. In southern Taiwan, we encountered 3 cases of invasive infections caused by Salmonella enterica serotype Choleraesuis with resistance to ciprofloxacin and ceftriaxone. Resistance to ciprofloxacin was related to nucleotide mutations in gyrA and parC, and resistance to ceftriaxone was related to the presence of CMY-2 beta -lactamase.