Avermectins and milbemycins against Fasciola hepatica: In vivo drug efficacy and in Vitro receptor binding

1995 ◽  
Vol 25 (8) ◽  
pp. 923-927 ◽  
Author(s):  
W.L. Shoop ◽  
D.A. Ostlind ◽  
S.P. Rohrer ◽  
G. Mickle ◽  
H.W. Haines ◽  
...  
Keyword(s):  
Receptor Binding ◽  
Fasciola Hepatica ◽  
Drug Efficacy

scholarly journals Assessing the Efficacy of Albendazole against Fasciola hepatica in Naturally Infected Cattle by In Vivo and In Vitro Methods

2021 ◽  
Vol 8 (11) ◽  
pp. 249
Author(s):  
Michal Babják ◽  
Alžbeta Königová ◽  
Ľudmila Burcáková ◽  
Michaela Komáromyová ◽  
Michaela Urda Dolinská ◽  
...  
Keyword(s):  
Fasciola Hepatica ◽  
Anthelmintic Resistance ◽  
Drug Efficacy ◽  
Cattle Farm ◽  
In Vitro Methods ◽  
Faecal Samples ◽  
Faecal Egg Count ◽  
History Of

This study was performed on a cattle farm with a long-term use of albendazole (ABZ) and a permanent history of fasciolosis for comparing in vivo and in vitro methods for the detection of anthelmintic resistance and drug efficacy. A selected group of 10 Charolais cows was treated in autumn 2020 with ABZ at a dose of 7.5 mg/kg body weight. Another group of 10 cows remained untreated as a control. The faecal egg count reduction test was used to determine in vivo efficacy. The percentage reduction of eggs on day 14 after treatment ranged from 77 to 81.8%, depending on the formula used for calculation. The in vitro egg hatch test (EHT) was used as a second diagnostic method. F. hepatica eggs for the EHT were isolated from faecal samples. The test was performed in two versions differing in the length of incubation with ABZ (12 h and 15 d). The percentage of eggs with inhibited development at a concentration of 0.5 μM in both versions of the EHT agreed with the in vivo results. Ovicidal activity at a concentration of 0.5 μM in the 12-h version suggested a reduced efficacy of ABZ (65.40%). An EHT prepared using pooled faecal samples was a prospective method for the detection of efficacy and ABZ resistance in F. hepatica.

scholarly journals A Novel Infection Protocol in Zebrafish Embryo to Assess Pseudomonas aeruginosa Virulence and Validate Efficacy of a Quorum Sensing Inhibitor In Vivo

Pathogens ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 401
Author(s):  
Pauline Nogaret ◽  
Fatima El El Garah ◽  
Anne-Béatrice Blanc-Potard
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Animal Model ◽  
Quorum Sensing ◽  
Drug Testing ◽  
Drug Efficacy ◽  
Embryo Viability ◽  
Immersion Method ◽  
Opportunistic Human Pathogen

The opportunistic human pathogen Pseudomonas aeruginosa is responsible for a variety of acute infections and is a major cause of mortality in chronically infected cystic fibrosis patients. Due to increased resistance to antibiotics, new therapeutic strategies against P. aeruginosa are urgently needed. In this context, we aimed to develop a simple vertebrate animal model to rapidly assess in vivo drug efficacy against P. aeruginosa. Zebrafish are increasingly considered for modeling human infections caused by bacterial pathogens, which are commonly microinjected in embryos. In the present study, we established a novel protocol for zebrafish infection by P. aeruginosa based on bath immersion in 96-well plates of tail-injured embryos. The immersion method, followed by a 48-hour survey of embryo viability, was first validated to assess the virulence of P. aeruginosa wild-type PAO1 and a known attenuated mutant. We then validated its relevance for antipseudomonal drug testing by first using a clinically used antibiotic, ciprofloxacin. Secondly, we used a novel quorum sensing (QS) inhibitory molecule, N-(2-pyrimidyl)butanamide (C11), the activity of which had been validated in vitro but not previously tested in any animal model. A significant protective effect of C11 was observed on infected embryos, supporting the ability of C11 to attenuate in vivo P. aeruginosa pathogenicity. In conclusion, we present here a new and reliable method to compare the virulence of P. aeruginosa strains in vivo and to rapidly assess the efficacy of clinically relevant drugs against P. aeruginosa, including new antivirulence compounds.

In vitro and in vivo receptor binding and deoxyglucose studies in rat brain with the potential antipsychotic Org 5222

1990 ◽  
Vol 183 (5) ◽  
pp. 1623
Author(s):  
J.A.D.M. Tonnaer ◽  
P. Room ◽  
W.M.J.B. Van Gemert ◽  
L.P.C. Delbressine ◽  
T. de Boer ◽  
...  
Keyword(s):  
Rat Brain ◽  
Receptor Binding ◽  
In Vivo Receptor Binding

scholarly journals Transcriptomic analysis reveals a role for the nervous system in regulating growth and development of Fasciola hepatica juveniles

2022 ◽  
Author(s):  
Emily Robb ◽  
Erin McCammick ◽  
Duncan Wells ◽  
Paul McVeigh ◽  
Erica Gardiner ◽  
...  
Keyword(s):  
Nervous System ◽  
Rapid Growth ◽  
Growth And Development ◽  
Liver Fluke ◽  
Fasciola Hepatica ◽  
Expression Profiles ◽  
Neuronal Signalling ◽  
Growth Development

Fasciola spp. liver fluke have significant impacts in veterinary and human medicine. The absence of a vaccine and increasing anthelmintic resistance threaten sustainable control and underscore the need for novel flukicides. Functional genomic approaches underpinned by in vitro culture of juvenile Fasciola hepatica facilitate control target validation in the most pathogenic life stage. Comparative transcriptomics of in vitro and in vivo maintained 21 day old F. hepatica finds that 86% of genes are expressed at similar levels across maintenance treatments suggesting commonality in core biological functioning within these juveniles. Phenotypic comparisons revealed higher cell proliferation and growth rates in the in vivo juveniles compared to their in vitro counterparts. These phenotypic differences were consistent with the upregulation of neoblast-like stem cell and cell-cycle associated genes in in vivo maintained worms. The more rapid growth/development of in vivo juveniles was further evidenced by a switch in cathepsin protease expression profiles, dominated by cathepsin B in in vitro juveniles and then by cathepsin L in in vivo juveniles. Coincident with more rapid growth/development was the marked downregulation of both classical and peptidergic neuronal signalling components in in vivo maintained juveniles, supporting a role for the nervous system in regulating liver fluke growth and development. Differences in the miRNA complements of in vivo and in vitro juveniles identified 31 differentially expressed miRNAs, notably fhe-let-7a-5p , fhe-mir-124-3p and, miRNAs predicted to target Wnt-signalling, supporting a key role for miRNAs in driving the growth/developmental differences in the in vitro and in vivo maintained juvenile liver fluke. Widespread differences in the expression of neuronal genes in juvenile fluke grown in vitro and in vivo expose significant interplay between neuronal signalling and the rate of growth/development, encouraging consideration of neuronal targets in efforts to dysregulate growth/development for parasite control.

A comparison of in vivo and in vitro neuroimaging of 5-HT1A receptor binding sites in the cat brain

2006 ◽  
Vol 31 (3) ◽  
pp. 226-232 ◽  
Author(s):  
Nicolas Aznavour ◽  
Latifa Rbah ◽  
Lucienne Léger ◽  
Colette Buda ◽  
Jean-Pierre Sastre ◽  
...  
Keyword(s):  
Receptor Binding ◽  
Binding Sites ◽  
Cat Brain

scholarly journals Soluble Heparin and Heparan Sulfate Glycosaminoglycans Interfere with Sonic Hedgehog Solubilization and Receptor Binding

Molecules ◽  
2019 ◽  
Vol 24 (8) ◽  
pp. 1607 ◽  
Author(s):  
Manikowski ◽  
Jakobs ◽  
Jboor ◽  
Grobe
Keyword(s):  
Heparan Sulfate ◽  
Sonic Hedgehog ◽  
Receptor Binding ◽  
Feedback Loop ◽  
Cancer Cell Growth ◽  
Shh Signaling ◽  
Epithelial Cancers ◽  
And Function

Sonic hedgehog (Shh) signaling plays a tumor-promoting role in many epithelial cancers. Cancer cells produce soluble a Shh that signals to distant stromal cells that express the receptor Patched (Ptc). These receiving cells respond by producing other soluble factors that promote cancer cell growth, generating a positive feedback loop. To interfere with reinforced Shh signaling, we examined the potential of defined heparin and heparan sulfate (HS) polysaccharides to block Shh solubilization and Ptc receptor binding. We confirm in vitro and in vivo that proteolytic cleavage of the N-terminal Cardin–Weintraub (CW) amino acid motif is a prerequisite for Shh solubilization and function. Consistent with the established binding of soluble heparin or HS to the Shh CW target motif, both polysaccharides impaired proteolytic Shh processing and release from source cells. We also show that HS and heparin bind to, and block, another set of basic amino acids required for unimpaired Shh binding to Ptc receptors on receiving cells. Both modes of Shh activity downregulation depend more on HS size and overall charge than on specific HS sulfation modifications. We conclude that heparin oligosaccharide interference in the physiological roles of HS in Shh release and reception may be used to expand the field of investigation to pharmaceutical intervention of tumor-promoting Shh functions.

In Vitro Androgen Receptor Binding Affinity and in Vivo Inhibitory Activity of 5?-Pregnane-3, 20-Dione

1988 ◽  
Vol 529 (1 Fourth Colloq) ◽  
pp. 239-241
Author(s):  
SAUDHAMINI PARTHASARATHY ◽  
ANDREA CHIN ◽  
VIRGINIA MALLOY ◽  
JONATHAN MATIAS
Keyword(s):  
Androgen Receptor ◽  
Binding Affinity ◽  
Receptor Binding ◽  
Inhibitory Activity ◽  
Receptor Binding Affinity

α1-Acid glycoprotein expressed in the plasma of chronic myeloid leukemia patients does not mediate significant in vitro resistance to STI571

Blood ◽  
2002 ◽  
Vol 99 (2) ◽  
pp. 713-715 ◽  
Author(s):  
Heather G. Jørgensen ◽  
Moira A. Elliott ◽  
Elaine K. Allan ◽  
Christine E. Carr ◽  
Tessa L. Holyoake ◽  
...  
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Plasma Proteins ◽  
Myeloid Leukemia ◽  
Philadelphia Chromosome ◽  
Drug Efficacy ◽  
Acid Glycoprotein ◽  
Proliferation In Vitro ◽  
Normal Controls

Abstract Despite the efficacy of STI571 (Glivec, Novartis, Basle, Switzerland) in treating chronic myeloid leukemia (CML), drug resistance has already been noted both in vitro and in vivo. As plasma proteins, including alpha-1-acid glycoprotein (AGP), may reduce drug efficacy through binding, AGP was investigated for its ability to interact with STI571.  At all stages of CML, AGP plasma level was significantly higher than in normal controls (P < .05). The glycoprotein was purified from normal plasma and individual chronic myeloid leukemia (CML) patients' plasma by low-pressure chromatography. The influence of α1-acid glycoprotein (AGP), in the presence of STI571, on the proliferation of Philadelphia chromosome–positive (Ph+) cells was examined. Normal AGP, even at supraphysiological concentrations, did not block the effect of STI571 on K562-cell proliferation in vitro. Moreover, CML-derived AGP failed to block the effect of STI571 on Ph+ cells in vitro. Thus, these in vitro findings suggest that AGP will not abrogate the antileukemic activity of STI571.

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