Synergistic Activity of Nitroimidazole-Oxazolidinone Conjugates against Anaerobic Bacteria.

The introductions of the bicyclic 4-nitroimidazole and the oxazolidinone classes of antimicrobial agents represented the most significant advancements in the infectious disease area during the past two decades. Pretomanid, a bicyclic 4-nitroimidazole, and linezolid, an oxazolidinone, are also part of a combination regimen approved recently by the US Food and Drug Administration for the treatment of pulmonary, extensively drug resistant (XDR), treatment-intolerant or nonresponsive multidrug-resistant (MDR) Mycobacterium tuberculosis (TB). To identify new antimicrobial agents with reduced propensity for the development of resistance, a series of dual-acting nitroimidazole-oxazolidinone conjugates were designed, synthesized and evaluated for their antimicrobial activity. Compounds in this conjugate series have shown synergistic activity against a panel of anaerobic bacteria, including those responsible for serious bacterial infections.

Synthesis, structure, and ethylene polymerization behavior of nickel complexes based on benzoylmethylenetri(2-alkoxylphenyl)phosphorane.

Several new nickel complexes are prepared by the treatment of the stabilized ylide benzoylmethylenetri(2-alkoxylphenyl)phosphorane with Ni(cod)(2) in the presence of PPh(3). X-Ray diffraction studies reveal that a distorted square planar geometry around Ni(II) is adopted. Upon treatment with Ni(cod)(2), the nickel complexes are sufficiently robust for ethylene polymerization. The existence of 2-alkoxyl-aryl substituents on phosphorus improves the catalytic activities. The highest activity (2.1 × 10(6) g mol(-1) h(-1)) is achieved when tri(2-isopropoxy-phenyl)phosphorane is employed (5e), which is one order higher than the corresponding SHOP catalyst. NMR analysis shows that the polyethylene mainly contains terminal double bonds and is highly linear.

Influence of antegrade pulmonary blood flow on the hemodynamic performance of bidirectional cavopulmonary anastomosis: a numerical study.

The role and effect of preserved antegrade pulmonary blood flow (APBF) at the time of bidirectional cavopulmonary anastomosis (BCPA) in the management of single-ventricle physiology is controversial. We investigated the influence of APBF on the fluid dynamics of BCPA connection using computational fluid dynamics (CFD). Patient-specific, three-dimensional geometry of a BCPA connection with native pulmonary artery (PA) trunk was reconstructed and transient CFD simulations were done at four predetermined mean flow rates of PA trunk (0.5L/min, 1L/min, 1.5L/min and 2L/min). During a cardiac cycle, the flow ratio of left pulmonary artery (LPA)/right pulmonary artery (RPA) increased from 1.91 to 2.50, and average control volume power loss increased from 0.76 mW to 18.05 mW when the mean flow rate of PA trunk changed from 0.5L/min to 2L/min. The pulsatility of pressures in LPA, RPA and superior vena cava became more prominent as the amount of APBF increased. Local fluid structures in the connection area at four levels of APBF differed from each other.

Patient-specific computational fluid dynamic simulation of a bilateral bidirectional Glenn connection.

Computational fluid dynamics (CFD) have been used to investigate the hemodynamic performance in cavopulmonary anastomosis and resulted in improved operative design. In this study, CFD simulations were performed in a patient-specific bilateral bidirectional Glenn (BBDG) connection model and the power losses as well as flow features at different levels of predetermined pulmonary flow splits were calculated and compared. The control volume power loss varied between 0.64 and 1.02 mW when the flow ratio of left pulmonary artery/right pulmonary artery changed from 80:20 to 20:80. The flow patterns within the connection area and the static pressures in the four vessels differed from each other as the pulmonary flow split changed. Power loss and flow patterns of this BBDG connection were influenced by the pulmonary flow split.