In vitro and in vivo evaluation of linezolid loaded electrospun PLGA and PLGA/PCL fiber mats for prophylaxis and treatment of MRSA induced prosthetic infections

In this study, it was aimed to formulate linezolid loaded electrospun PLGA and PCL fiber mats doing controlled drug release, to be used in the treatment and prophylaxis of the prosthesis related infections. The effect of PLGA concentration, PLGA to PCL ratio and the amount of linezolid on the fiber and mat properties were examined. Fiber diameter has been shown to increase with increasing amount of PLGA and linezolid. Increase in PLGA amount resulted in reduced linezolid release, whereas increase in linezolid amount resulted in increased drug release. All PLGA fiber mats have shown to have favorable encapsulation efficiency (>= 73%) and mechanical properties. Encapsulation efficiency and the mechanical properties deteriorated with the addition of PCL to the formulations. PLGA fiber mats have shown a biphasic controlled release and in vitro antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA), pattern up to one month. The formulation selected as the optimum has been evaluated in vivo on the infected rats, which had prosthetic implantation after bone fracture. Consequently, it has been demonstrated microbiologically and histopathologically that a more efficient therapy and prophylaxis have been achieved with a 37-fold lower dose of linezolid

Electrocardiographic changes in primary spontaneous pneumothorax

WOS: 000339225600019Background: This study aims to evaluate the electrocardiographic (ECG) changes in patients with primary spontaneous pneumothorax. Methods: A total of 48 patients (42 males, 6 females; mean age 29.7 +/- 12.5 years, range 15 to 58 years) with PSP were prospectively analyzed between November 2010 and November 2011. Pneumothorax size was calculated using the Rhea method. At least two standard 12-lead ECG were obtained for each patient (after the diagnosis of pneumothorax and prior to drain placement - ECG(pneumothorax), and after a complete re-expansion of the lung was achieved and confirmed radiologically - ECG(re-expanded)). P wave measurement, PR distance, QRS distance, QT interval and QT interval corrected for heart rate (QTc) were calculated. Heart rate (bpm), axis deviation measurement and the QRS amplitudes (QRSV1-6) in precordial leads were calculated. Results: There were 29 cases (60.4%) of left-sided and 19 cases (39.6%) of right-sided pneumothorax. The mean relative volume of pneumothorax was 43.0 +/- 21.5%. The most common symptoms included chest pain in 34 patients (70.8%) and dyspnea in 14 patients (29.2%). The pneumothorax duration was 24 hours in 18 patients (37.5%). There was a statistically significant difference between before and after the treatment for QT duration, axis deviation, heart rate, QRSV1, QRSV4, QRSV5 and QRSV6 (respectively; p=0.001, p=0.023, p=0.001, p=0.010, p=0.046, p=0.000, p=0.008). A total of seven patients had relevant QRS abnormalities including incomplete right bundle branch block in three patients, ST elevation in two patients and T-wave pointedness in one patient. Conclusion: Our study results suggest that left and right lung pneumothorax may cause axis variation, which is more pronounced in women, and that voltage increases after drainage in QRSV 4, 5 and 6 leads. In addition, pneumothorax may lead to specific ECG variations such as right bundle branch block and ST variations