Synergistic Anti-bacterial Effects of Phellinus baumii Ethyl Acetate Extracts and ß-Lactam Antimicrobial Agents Against Methicillin-Resistant Staphylococcus aureus.

BACKGROUND: The development of new drugs or alternative therapies effective against methicillin-resistant Staphylococcus aureus (MRSA) is of great importance, and various natural anti-MRSA products are good candidates for combination therapies. We evaluated the antibacterial activities of a Phellinus baumii ethyl acetate extract (PBEAE) and its synergistic effects with ß-lactams against MRSA. METHODS: The broth microdilution method was used to determine the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of the PBEAE. The PBEAE synergistic effects were determined by evaluating the MICs of anti-staphylococcal antibiotic mixtures, with or without PBEAE. Anti-MRSA synergistic bactericidal effects of the PBEAE and ß-lactams were assessed by time-killing assay. An ELISA was used to determine the effect of the PBEAE on penicillin binding protein (PBP)2a production. RESULTS: The MICs and MBCs of PBEAE against MRSA were 256-512 and 1,024-2,048 µg/mL, respectively. The PBEAE significantly reduced MICs of all ß-lactams tested, including oxacillin, cefazolin, cefepime, and penicillin. However, the PBEAE had little or no effect on the activity of non-ß-lactams. Time-killing assays showed that the synergistic effects of two ß-lactams (oxacillin and cefazolin) with the PBEAE were bactericidal in nature (Δlog10 colony forming unit/mL at 24 hr: 2.34-2.87 and 2.10-3.04, respectively). The PBEAE induced a dose-dependent decrease in PBP2a production by MRSA, suggesting that the inhibition of PBP2a production was a major synergistic mechanism between the ß-lactams and the PBEAE. CONCLUSIONS: PBEAE can enhance the efficacy of ß-lactams for combined therapy in patients infected with MRSA.

Fully Implantable Deep Brain Stimulation System with Wireless Power Transmission for Long-term Use in Rodent Models of Parkinson's Disease.

OBJECTIVE: The purpose of this study to develop new deep-brain stimulation system for long-term use in animals, in order to develop a variety of neural prostheses. METHODS: Our system has two distinguished features, which are the fully implanted system having wearable wireless power transfer and ability to change the parameter of stimulus parameter. It is useful for obtaining a variety of data from a long-term experiment. RESULTS: To validate our system, we performed pre-clinical test in Parkinson's disease-rat models for 4 weeks. Through the in vivo test, we observed the possibility of not only long-term implantation and stability, but also free movement of animals. We confirmed that the electrical stimulation neither caused any side effect nor damaged the electrodes. CONCLUSION: We proved possibility of our system to conduct the long-term pre-clinical test in variety of parameter, which is available for development of neural prostheses.

Short-Term Results of Total Knee Arthroplasty with Anterior-Posterior Glide LCS Mobile-Bearing System.

PURPOSE: To evaluate the clinical and radiological results of total knee arthroplasty (TKA) using the anterior-posterior glide (APG) low contact stress (LCS) mobile-bearing system. MATERIALS AND METHODS: We evaluated 130 knees in 117 patients who had undergone TKA with APG LCS mobile-bearing system between September 2005 and July 2007 and could be followed over 5 years. The mean follow-up period was 68 months. The clinical and radiological results were evaluated using the American Knee Society Scoring System, Oxford knee score and the American Knee Society Roentgenographic Evaluation and Scoring System. And we analyzed short-term postoperative complications. RESULTS: The average range of motion of the knee joint was 107.9° (range, 70° to 135°) preoperatively and 125.2° (range, 90° to 135°) at the last follow-up. The average knee and functional scores were improved from 39.1 and 42.0 to 71.2 and 75.6, respectively, between the preoperative and last follow-up evaluation. The Oxford knee score was decreased from 42.9 preoperatively to 23.1 at the last follow-up. The femoro-tibial angle (anatomical axis) changed from 10.1° varus preoperatively to 3.3° valgus at the last follow-up. Radiolucency was observed in 14% of all cases. There were 1 case of traumatic dislocation of the polyethylene liner, 1 case of aseptic loosening and 6 cases of posterior instability because of posterior cruciate ligament (PCL) insufficiency. CONCLUSIONS: TKA with APG LCS mobile-bearing system demonstrated relatively good short-term clinical and radiological results. However, further considerations for posterior instability associated with PCL insufficiency are needed.

Construction of a thermotolerant Saccharomyces cerevisiae strain for bioethanol production with reduced fermentation time and saccharifying enzyme dose.

A thermotolerant Saccharomyces cerevisiae mutant strain, TT6, was constructed after multi-parental hybridization of five mutant strains obtained by UV or NTG treatment of the original strain, S. cerevisiae KV1. When incubated at 40 degrees C in YPD broth, TT6 began to grow exponentially in 10 h, but KV1 did not show any noticeable growth even after 22 h. The thermotolerant growth of TT6 was confirmed by serial dilution assay at 42 degrees C; TT6 grew at a cell concentration (10(-5)) 10,000 times lower than that of KV1 (10(-1)). Whereas ethanol production from YP containing 23%; (w/v) glucose by KV1 decreased with increasing temperature from 30 degrees C to 36 degrees C, ethanol production by TT6 did not decrease at temperatures up to 37 degrees C. When TT6 was tested for ethanol production at 36 degrees C by simultaneous saccharification and fermentation (SSF) from 23% corn, 24 h of fermentation time or 50% of the glucoamylase dose was saved when compared with KV1 at 30 degrees C. The ethanol yield from corn by SSF with TT6 at 36 degrees C was 91.7% of the theoretical yield, whereas that of KV1 at 30 degrees C was 90.6%.