scholarly journals Pathogenesis ofAspergillus fumigatusand the Kinetics of Galactomannan in an In Vitro Model of Early Invasive Pulmonary Aspergillosis: Implications for Antifungal Therapy

2007 ◽  
Vol 195 (3) ◽  
pp. 455-466 ◽  
Author(s):  
William W. Hope ◽  
Michael J. Kruhlak ◽  
Caron A. Lyman ◽  
Ruta Petraitiene ◽  
Vidmantas Petraitis ◽  
...  
Keyword(s):  
Antifungal Therapy ◽  
In Vitro Model ◽  
Invasive Pulmonary Aspergillosis ◽  
Pulmonary Aspergillosis ◽  
Vitro Model ◽  
Kinetics Of

scholarly journals Investigation of Solvolysis Kinetics of New Synthesized Fluocinolone Acetonide C-21 Esters—An In Vitro Model for Prodrug Activation

Molecules ◽  
2011 ◽  
Vol 16 (3) ◽  
pp. 2658-2671 ◽  
Author(s):  
Bojan D. Markovic ◽  
Vladimir D. Dobricic ◽  
Sote M. Vladimirov ◽  
Olivera A. Cudina ◽  
Vladimir M. Savic ◽  
...  
Keyword(s):  
In Vitro Model ◽  
Fluocinolone Acetonide ◽  
Prodrug Activation ◽  
Vitro Model ◽  
Kinetics Of

scholarly journals Control of the Transdermal Delivery Process of Active Substances of the Phytocomplex during Phonophoresis in Model Experiments

2019 ◽  
Vol 7 (13) ◽  
pp. 2079-2083
Author(s):  
Liudmila Ivanovna Babaskina ◽  
Tatiana Mikhailovna Litvinova ◽  
Dmitrii Vladimirovich Babaskin ◽  
Olga Valerevna Krylova
Keyword(s):  
Dimethyl Sulfoxide ◽  
Transdermal Delivery ◽  
In Vitro Model ◽  
The Body ◽  
Model Experiments ◽  
Vitro Model ◽  
Franz Diffusion Cells ◽  
Kinetics Of ◽  
Active Substances

BACKGROUND: The scientific substantiation for the selection of therapeutically significant dosage of phytocomplex in the dosage form for phonophoresis, control over the delivery of active substances into the body, and what affects this process require the study of the kinetics of phytocomplex flavonoids delivery during phonophoresis. AIM: The aim was to study the possibilities of controlling the process of transdermal delivery of phytocomplex active substances (flavonoids) during phonophoresis in vitro model experiments. METHODS: Working compositions with different concentrations of phytocomplex for phonophoresis were used. The content of flavonoids in the compositions was determined using the spectrophotometric method and was calculated equivalent to quercetin, the flavonoid prevailing in the phytocomplex. The study of the kinetics of flavonoids delivery from working compositions was carried out using Franz diffusion cells and Carbosyl-P membranes. The authors determined the main parameters of the process and established the dependence of the delivery rate of flavonoids on their initial concentration in the working composition. The authors studied the effect of dimethyl sulfoxide and the base-forming substances of the working composition on the kinetics of phytocomplex flavonoid delivery during phonophoresis. RESULTS: The authors recorded an increase in the rate of delivery of the active substances from working compositions containing dimethyl sulfoxide into the model medium by almost 1.5-2 times during the first ten minutes of the experiment (approximate duration of the phonophoresis procedure). The authors proposed technological techniques for improvement of the phonophoresis method for the phytocomplex. The possibilities of control over the process of transdermal delivery of the phytocomplex active ingredients during phonophoresis in vitro model experiments were shown. CONCLUSION: The obtained results provide information for further pharmacological studies of the nature and mechanism of the effect of phytocomplex flavonoids during phonophoresis in the rehabilitation of patients with osteoarthrosis.

scholarly journals The Initial 96 Hours of Invasive Pulmonary Aspergillosis: Histopathology, Comparative Kinetics of Galactomannan and (1→3)-β-d-Glucan, and Consequences of Delayed Antifungal Therapy

2010 ◽  
Vol 54 (11) ◽  
pp. 4879-4886 ◽  
Author(s):  
William W. Hope ◽  
Vidmantas Petraitis ◽  
Ruta Petraitiene ◽  
Tamarra Aghamolla ◽  
John Bacher ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
Amphotericin B ◽  
Antifungal Therapy ◽  
Time Course ◽  
Invasive Pulmonary Aspergillosis ◽  
Rabbit Model ◽  
Pulmonary Aspergillosis ◽  
Lung Weight ◽  
Kinetics Of

ABSTRACT Acute invasive pulmonary aspergillosis is a rapidly progressive and frequently lethal infection. Relatively little is known about early events in the pathogenesis and relationship between the cell wall biomarkers galactomannan and (1→3)-β-d-glucan. The consequences of delayed antifungal therapy are also poorly defined. A persistently neutropenic rabbit model of invasive pulmonary aspergillosis was used to describe the histopathology of early invasive pulmonary aspergillosis and the kinetics of galactomannan and (1→3)-β-d-glucan. The time course of both molecules was mathematically modeled by using a population methodology, and Monte Carlo simulations were performed. The effect of progressive delay in the administration of amphotericin B deoxycholate 1 mg/kg at 24, 48, 72, and 96 h postinoculation on fungal burden, lung weight, pulmonary infarct score, and survival was determined. Histopathology showed phagocytosis of conidia by pulmonary alveolar macrophages at 4 h postinoculation. At 12 to 24 h, there was a progressive focal inflammatory response with conidial germination and hyphal extension. Subsequently, hyphae invaded into the contiguous lung. Galactomannan and (1→3)-β-d-glucan had similar trajectories, and both exhibited considerable interindividual variability, which was reflected in Monte Carlo simulations. Concentrations of both molecules began to rise <24 h postinoculation before pulmonary hemorrhagic infarction was present. Delays of 72 and 96 h in the administration of amphotericin B resulted in fungal burdens and lung weights that were indistinguishable from those of controls, respectively. Galactomannan and (1→3)-β-d-glucan have similar kinetics and are comparable biomarkers of early invasive pulmonary aspergillosis. Antifungal treatment at ≥48 h postinoculation is associated with suboptimal therapeutic outcomes.

scholarly journals Liposomal Thyroxine: A Noninvasive Model for Transplacental Fetal Therapy*

1997 ◽  
Vol 82 (10) ◽  
pp. 3271-3277
Author(s):  
Rekha Bajoria ◽  
Nicholas M. Fisk ◽  
Soli F. Contractor
Keyword(s):  
In Vitro Model ◽  
Human Term Placenta ◽  
Transplacental Transfer ◽  
Term Placenta ◽  
Marker Substances ◽  
Anionic Liposomes ◽  
Vitro Model ◽  
Kinetics Of

Abstract Drugs that cross the placenta sparingly are currently given directly to the fetus by invasive procedures. We investigated whether anionic small unilamellar (SUV) liposomes of different lipid compositions enhanced the transfer and uptake of T4 in an in vitro model of perfused human term placenta. T4-encapsulated anionic liposomes were prepared using lecithin (F-SUV) or distearoyl phosphatidylcholine (S-SUV) with cholesterol and dicetylcholine. The size distribution, encapsulation efficiency, and stability were determined in blood-based media. The transfer kinetics of free and liposomally encapsulated T4 were studied in a dually perfused isolated lobule of human term placenta, with creatinine and liposomal carboxyfluorescein as marker substances. Concentrations of T4 and rT3 were measured by RIA. T4 crossed the placenta sparingly (1.9 ± 0.5%) because it was metabolized to rT3 (9.2 ± 1.3%). Transplacental transfer of T4 was significantly increased by F-SUV (15.8 ± 2.1%; P &lt; 0.001) and S-SUV liposomes (7.1 ± 1.2%; P &lt; 0.001), with a concomitant decrease in fetal rT3 levels (P &lt; 0.001). Placental uptake of F-SUV (13.5 ± 2.0%; P &lt; 0.001) was greater than that of S-SUV liposomes (6.7 ± 0.8%; P &lt; 0.001). Our data suggest that anionic liposomes increase transplacental transfer of T4. If confirmed in vivo, liposomes may provide an alternative noninvasive method of drug delivery to the fetus.

A simple in vitro model to study the release kinetics of liposome encapsulated material

1998 ◽  
Vol 56 (1-3) ◽  
pp. 41-51 ◽  
Author(s):  
Regine Peschka ◽  
Cathi Dennehy ◽  
Francis C Szoka Jr
Keyword(s):  
In Vitro Model ◽  
Release Kinetics ◽  
Vitro Model ◽  
Kinetics Of

Removal of Cephalosporins by Continuous Arteriovenous Ultrafiltration (CAVU) and Hemofiltration (CAVH)

1989 ◽  
Vol 12 (6) ◽  
pp. 379-383 ◽  
Author(s):  
A.H. Lau ◽  
K. Pyle ◽  
N.O. Kronfol ◽  
C.R. Libertin
Keyword(s):  
Protein Binding ◽  
In Vitro Model ◽  
Plasma Drug ◽  
Flow Rates ◽  
Drug Concentrations ◽  
Vitro Model ◽  
Arterial Plasma ◽  
Kinetics Of ◽  
Venous Plasma

Cephalosporins are used with increasing frequency for sepsis treatment in patients receiving CAVU and CAVH. The different cephalosporins share the same basic molecular structure, yet they exhibit varied extent of plasma protein binding. Different amounts of the antibiotics may be removed by the ultrafiltration procedure because of these variations of physicochemical properties. We evaluated the sieving of eight new cephalosporins across the hemofilter membrane using an in vitro model. Bovine blood was perfused through polysulfone membranes at blood and ultrafiltrate flow rates of 100 and 20 ml/min respectively. Arterial plasma, venous plasma and ultrafiltrate drug concentrations were used to determine sieving coefficients. The sieving coefficients correlated well with the ultrafiltrate-arterial plasma drug concentration ratio (r= 0.679 - 0.972) but poorly with the extent of protein binding. Factors other than protein binding may therefore affect the drug sieving. Based on the findings, it was predicted that 0.2 - 21.9% of the daily cephalosporin dose may be removed by the CAVU and CAVH treatment. The need to alter drug dosages depends on the techniques of the ultrafiltration and hemofiltration procedure, the kinetics of the cephalosporins in patients, the sensitivity of the pathogen and the nature of the infection.

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