scholarly journals Deposition of Inhaled Levofloxacin in Cystic Fibrosis Lungs Assessed by Functional Respiratory Imaging

Pharmaceutics ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2051
Author(s):  
Carsten Schwarz ◽  
Claudio Procaccianti ◽  
Benjamin Mignot ◽  
Hosein Sadafi ◽  
Nicolas Schwenck ◽  
...  

Pulmonary infections caused by Pseudomonas aeruginosa (PA) represent the leading cause of pulmonary morbidity in adults with cystic fibrosis (CF). In addition to tobramycin, colistin, and aztreonam, levofloxacin has been approved in Europe to treat PA infections. Nevertheless, no lung deposition data on inhaled levofloxacin are yet available. We conducted a Functional Respiratory Imaging (FRI) study to predict the lung deposition of levofloxacin in the lungs of patients with CF. Three-dimensional airway models were digitally reconstructed from twenty high-resolution computed tomography scans obtained from historical patients’ records. Levofloxacin aerosols generated with the corresponding approved nebuliser were characterised according to pharmacopeia. The obtained data were used to inform a computational fluid dynamics simulation of levofloxacin lung deposition using breathing patterns averaged from actual CF patients’ spirometry data. Levofloxacin deposition in the lung periphery was significantly reduced by breathing patterns with low inspiratory times and high inspiratory flow rates. The intrathoracic levofloxacin deposition percentages for moderate and mild CF lungs were, respectively, 37.0% ± 13.6 and 39.5% ± 12.9 of the nominal dose. A significant albeit modest correlation was found between the central-to-peripheral deposition (C/P) ratio of levofloxacin and FEV1. FRI analysis also detected structural differences between mild and moderate CF airways. FRI revealed a significant intrathoracic deposition of levofloxacin aerosols, which distributed preferentially to the lower lung lobes, with an influence of the deterioration of FEV1 on the C/P ratio. The three-dimensional rendering of CF airways also detected structural differences between the airways of patients with mild and moderate CF.

2021 ◽  
Vol 22 (3) ◽  
pp. 1400
Author(s):  
Ciresthel Bello-Rios ◽  
Sarita Montaño ◽  
Olga Lilia Garibay-Cerdenares ◽  
Lilian Esmeralda Araujo-Arcos ◽  
Marco Antonio Leyva-Vázquez ◽  
...  

The oncogenic potential of high-risk human papillomavirus (HPV) is predicated on the production of the E6 and E7 oncoproteins, which are responsible for disrupting the control of the cell cycle. Epidemiological studies have proposed that the presence of the N29S and H51N variants of the HPV16 E7 protein is significantly associated with cervical cancer. It has been suggested that changes in the amino acid sequence of E7 variants may affect the oncoprotein 3D structure; however, this remains uncertain. An analysis of the structural differences of the HPV16 E7 protein and its variants (N29S and H51N) was performed through homology modeling and structural refinement by molecular dynamics simulation. We propose, for the first time, a 3D structure of the E7 reference protein and two of Its variants (N29S and H51N), and conclude that the mutations induced by the variants in N29S and H51N have a significant influence on the 3D structure of the E7 protein of HPV16, which could be related to the oncogenic capacity of this protein.


2011 ◽  
Vol 191 (4) ◽  
pp. 1168-1179 ◽  
Author(s):  
Craig R. Brodersen ◽  
Eric F. Lee ◽  
Brendan Choat ◽  
Steven Jansen ◽  
Ronald J. Phillips ◽  
...  

1994 ◽  
Vol 373 ◽  
Author(s):  
Roger E. Stoller

AbstractA series of high-energy, up to 20 keV, displacement cascades in iron have been investigated for times up to 200 ps at 100 K using the method of molecular dynamics simulation. Thesimulations were carried out using the MOLDY code and a modified version of the many-bodyinteratomic potential developed by Finnis and Sinclair. The paper focuses on those results obtained at the highest energies, 10 and 20 keV. The results indicate that the fraction of the Frenkel pairs surviving in-cascade recombination remains fairly high in iron and that the fraction of the surviving point defects that cluster is lower than in materials such as copper. In particular, vacancy clustering appears to be inhibited in iron. Some of the interstitial clusters were observed to exhibit an unexpectedly complex, three-dimensional morphology. The observations are discussed in terms of their relevance to microstructural evolution and mechanical property changes in irradiated iron-based alloys.


Robotica ◽  
2010 ◽  
Vol 29 (5) ◽  
pp. 733-743 ◽  
Author(s):  
Conghui Liang ◽  
Hao Gu ◽  
Marco Ceccarelli ◽  
Giuseppe Carbone

SUMMARYA mechanical design and dynamics walking simulation of a novel tripod walking robot are presented in this paper. The tripod walking robot consists of three 1-degree-of-freedom (DOF) Chebyshev–Pantograph leg mechanisms with linkage architecture. A balancing mechanism is mounted on the body of the tripod walking robot to adjust its center of gravity (COG) during walking for balancing purpose. A statically stable tripod walking gait is performed by synchronizing the motions of the three leg mechanisms and the balancing mechanism. A three-dimensional model has been elaborated in SolidWorks® engineering software environment for a characterization of a feasible mechanical design. Dynamics simulation has been carried out in the MSC.ADAMS® environment with the aim to characterize and to evaluate the dynamic walking performances of the proposed design with low-cost easy-operation features. Simulation results show that the proposed tripod walking robot with proper input torques, gives limited reaction forces at the linkage joints, and a practical feasible walking ability on a flatten ground.


Author(s):  
Guodong Sun ◽  
Xuejing Duan ◽  
Bo Hao ◽  
Afshin Davarpanah

Nitrogen oxides are considered as one of the greenhouse gases. Among the most significant emission sources for this gas is a natural gas-fired power plant. The United Nations General assembly suggested in 1988 that human activities can negatively impact weather patterns, and thus they should be controlled. This control policy can improve the efficiency of final consumers such as power plants, cars, or other energy-intensive industries. In this paper, the existing strategies and explicitly making the dry low nitrogen oxides burner reduce greenhouse gases in power plants are explored. The geometry of the burner has been produced in a three-dimensional form in GAMBIT software, and the results of the simulation have been expressed through FLUENT software. Contours of pressure, temperature, and velocity of the fluid in the furnace are also derived. It is concluded that the dry low nitrogen oxides burners plan has a better result compared with other strategies.


Biochemistry ◽  
1990 ◽  
Vol 29 (45) ◽  
pp. 10317-10322 ◽  
Author(s):  
Lennart Nilsson ◽  
Agneta Aahgren-Staalhandske ◽  
Ann Sofie Sjoegren ◽  
Solveig Hahne ◽  
Britt Marie Sjoeberg

Sign in / Sign up

Export Citation Format

Share Document