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1.
J Med Chem ; 67(12): 9991-10004, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38888038

RESUMEN

Different from most antiretroviral drugs that act as passive defenders to inhibit HIV-1 replication inside the host cell, virus inactivators can attack and inactivate HIV-1 virions without relying on their replication cycle. Herein, we describe the discovery of a hydrocarbon double-stapled helix peptide, termed D26. D26 is based on the HIV-1 gp41 protein lentiviral lytic peptide-3 motif (LLP3) sequence, which can efficiently inhibit HIV-1 infection and inactivate cell-free HIV-1 virions. It was noted that D26 was highly resistant to proteolytic degradation and exhibited a remarkably extended in vivo elimination half-life. Additionally, relative to its linear, nonstapled version, D26 exhibited much higher exposure in sanctuary sites for HIV-1. Amazingly, this lead compound also demonstrated detectable oral absorption. Thus, it can be concluded that D26 is a promising candidate for further development as a long-acting, orally applicable HIV-1 inactivator for the treatment of HIV-1 infection.


Asunto(s)
Fármacos Anti-VIH , Disponibilidad Biológica , Proteína gp41 de Envoltorio del VIH , VIH-1 , Péptidos , VIH-1/efectos de los fármacos , Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/química , Fármacos Anti-VIH/farmacocinética , Humanos , Animales , Administración Oral , Proteína gp41 de Envoltorio del VIH/metabolismo , Proteína gp41 de Envoltorio del VIH/química , Péptidos/química , Péptidos/farmacología , Péptidos/farmacocinética , Descubrimiento de Drogas , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Semivida
2.
BMC Vet Res ; 20(1): 251, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38849822

RESUMEN

AIM OF THE WORK: The study was conducted to evaluate the influence of theophylline pre-treatment on serum pharmacokinetics and milk elimination of tylosin following single intramuscular (IM) administrations in lactating goats. METHODS AND RESULTS: In a cross-over study, tylosin was injected via intramuscular (IM) at a single dose of 15 mg/kg b.wt. After a one-month washout period goats received theophylline at a daily IM dose of 2 mg/kg b.wt. for seven consecutive days then tylosin was injected IM dose of 15 mg/kg b.wt. two hours after the last theophylline dosing. Blood samples were collected before and at 0.25, 0.5, 0.75, 1, 2, 4, 6, 8, 10, 12, and 24 h post-injection. Samples were left to clot and then centrifuged to yield serum. Milk samples were collected before and at 0.5, 1, 2, 4, 6, 8, 10, 12, 24, 48, and 72 h post-injection from each goat by hand milking. Tylosin serum concentrations were determined by high-performance liquid chromatography (HPLC). Tylosin concentrations versus time were analyzed by a noncompartmental method. Tylosin Cmax significantly declined from 1.73 ± 0.10 to 1.01 ± 0.11 µg/ml, and attained Tmax values of 2 and 1 h, respectively in theophylline-pretreated goats. Moreover, theophylline pretreatment significantly shortened the elimination half-life (t1/2el) from 6.94 to 1.98 h, t1/2ka from 0.62 to 0.36 h and the mean residence time (MRT) from 8.02 to 4.31 h, also Vz/F and AUCs decreased from 11.91 to 7.70 L/kg and from 12.64 to 4.57 µg*h/ml, respectively, consequently, theophylline enhanced the clearance (Cl/F) of tylosin from the body. Similarly, tylosin milk concentrations were significantly lower in theophylline-pretreated goats than in goats that received tylosin alone and were detected up to 24 and 72 h in both groups, respectively. Moreover, the t1/2el and AUCs were significantly decreased from 14.68 ± 1.97 to 4.72 ± 0.48 h, and from 181 to 67.20 µg*h/ml, respectively. CONCLUSIONS: The withdrawal period for tylosin in goat milk is at least 72 h. Theophylline pretreatment significantly decreases serum and milk tylosin concentrations to subtherapeutic levels, which could have serious clinical consequences such as failure of therapy. This means that after administering tylosin to goats, milk from these animals should not be consumed for at least 96 h to ensure that the milk is free from residues of the antibiotic.


Asunto(s)
Antibacterianos , Estudios Cruzados , Cabras , Lactancia , Leche , Teofilina , Tilosina , Animales , Cabras/metabolismo , Teofilina/farmacocinética , Teofilina/administración & dosificación , Teofilina/sangre , Tilosina/farmacocinética , Tilosina/administración & dosificación , Tilosina/sangre , Inyecciones Intramusculares/veterinaria , Leche/química , Femenino , Antibacterianos/farmacocinética , Antibacterianos/administración & dosificación , Antibacterianos/sangre , Semivida , Área Bajo la Curva
3.
Clin Transl Sci ; 17(6): e13853, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38847347

RESUMEN

The evidence of rivaroxaban's pharmacokinetics in obese compared with non-obese populations remains inconclusive. We aimed to compare the pharmacokinetic profile of rivaroxaban between obese and non-obese populations under fed state. Participants who met the study's eligibility criteria were assigned into one of two groups: obese (body mass index ≥35 kg/m2) or non-obese (body mass index 18.5-24.9 kg/m2). A single dose of rivaroxaban 20 mg was orally administered to each participant. Nine blood samples over 48 h, and multiple urine samples over 18 h were collected and analyzed for rivaroxaban concentration using ultra-performance liquid chromatography coupled with tandem mass detector. Pharmacokinetic parameters were determined using WinNonlin software. Thirty-six participants were recruited into the study. No significant changes were observed between obese and non-obese participants in peak plasma concentration, time to reach peak plasma concentration, area under the plasma concentration-time curve over 48 h or to infinity, elimination rate constant, half-life, apparent volume of distribution, apparent clearance, and fraction of drug excreted unchanged in urine over 18 h. Rivaroxaban's exposure was similar between the obese and non-obese subjects, and there were no significant differences in other pharmacokinetic parameters between the two groups. These results suggest that dose adjustment for rivaroxaban is probably unwarranted in the obese population.


Asunto(s)
Inhibidores del Factor Xa , Obesidad , Rivaroxabán , Humanos , Rivaroxabán/farmacocinética , Rivaroxabán/administración & dosificación , Rivaroxabán/sangre , Masculino , Femenino , Adulto , Inhibidores del Factor Xa/farmacocinética , Inhibidores del Factor Xa/administración & dosificación , Inhibidores del Factor Xa/sangre , Persona de Mediana Edad , Administración Oral , Índice de Masa Corporal , Área Bajo la Curva , Semivida , Adulto Joven
6.
Expert Opin Pharmacother ; 25(8): 985-997, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38825778

RESUMEN

INTRODUCTION: Unfractionated heparin is a widely used anticoagulant in critically ill patients. It has a well-established safety profile and remains an attractive option for clinicians due to its short half-life and reversibility. Heparin has a unique pharmacokinetic profile, which contributes to significant inter-patient and intra-patient variability in effect. The variability in anticoagulant effect combined with heparin's short half-life mean close monitoring is required for clinical efficacy and preventing adverse effects. To optimize heparin use in critically ill patients, effective monitoring assays and dose adjustment strategies are needed. AREAS COVERED: This paper explores the use of heparin as an anticoagulant and optimal approaches to monitoring in critically ill patients. EXPERT OPINION: Conventional monitoring assays for heparin dosing have significant limitations. Emerging data appear to favor using anti-Xa assay monitoring for heparin anticoagulation, which many centers have successfully adopted as the standard. The anti-Xa assay appears have important benefits relative to the aPTT for heparin monitoring in critically ill patients, and should be considered for broader use.


Asunto(s)
Anticoagulantes , Enfermedad Crítica , Monitoreo de Drogas , Heparina , Humanos , Heparina/administración & dosificación , Heparina/farmacocinética , Anticoagulantes/administración & dosificación , Anticoagulantes/farmacocinética , Anticoagulantes/uso terapéutico , Anticoagulantes/efectos adversos , Monitoreo de Drogas/métodos , Relación Dosis-Respuesta a Droga , Semivida , Guías de Práctica Clínica como Asunto , Inhibidores del Factor Xa/administración & dosificación , Inhibidores del Factor Xa/farmacocinética , Inhibidores del Factor Xa/efectos adversos , Inhibidores del Factor Xa/uso terapéutico
7.
Eur J Drug Metab Pharmacokinet ; 49(4): 467-475, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38748358

RESUMEN

BACKGROUND AND OBJECTIVE: Astaxanthin is a naturally occurring carotenoid with high anti-oxidant properties, but it is a very lipophilic compound with low oral bioavailability. This study was conducted to compare the pharmacokinetic parameters of a novel astaxanthin preparation based on micellar solubilization technology, NovaSOL® 400-mg capsules (Test product), and those of astaxanthin 400-mg capsules (reference product), after single oral dose administration to healthy male adults. METHODS: A single oral dose (400 mg equivalent to 8 mg astaxanthin) of test and reference astaxanthin were administered with 240 mL of water to 12 volunteers according to crossover design, in two phases, with a washout period of 1 week in between. Blood samples were collected at hourly intervals for the first 12 h, then at 24.0, 48.0, and 72.0 h after administration. Aliquots of plasma were centrifuged and the clear supernatant was injected into the high performance liquid chromatography-diode array detection (HPLC-DAD) system. Plasma concentration of astaxanthin versus time profiles were constructed, and the primary pharmacokinetic parameters, maximum concentration (Cmax), area under concentration time curve from time of administration (0) to time (t) [AUC0-t] or to infinity ∞, [AUC0-∞],  half-life (T½) and time to reach Cmax (Tmax) were calculated. RESULTS: The test micellar astaxanthin reached a Cmax of 7.21 µg/ml after 3.67 h compared to only 3.86 µg/ml after 8.5 h for the reference native astaxanthin. CONCLUSION: Micellar formulation of astaxanthin is capable of producing a high concentration of astaxanthin in plasma in a shorter time, thereby expected to provide faster potential therapeutic efficacy.


Asunto(s)
Área Bajo la Curva , Estudios Cruzados , Voluntarios Sanos , Micelas , Xantófilas , Xantófilas/farmacocinética , Xantófilas/administración & dosificación , Xantófilas/sangre , Humanos , Masculino , Adulto , Adulto Joven , Administración Oral , Semivida , Disponibilidad Biológica , Cápsulas/farmacocinética , Cromatografía Líquida de Alta Presión/métodos
8.
Eur J Pharm Biopharm ; 200: 114339, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38789061

RESUMEN

Peptides, despite their therapeutic potential, face challenges with undesirable pharmacokinetic (PK) properties and biodistribution, including poor oral absorption and cellular uptake, and short plasma elimination half-lives. Lipidation of peptides is a common strategy to improve their physicochemical and PK properties, making them viable drug candidates. For example, the plasma half-life of peptides has been extended via conjugation to lipids that are proposed to promote binding to serum albumin and thus protect against rapid clearance. Recent work has shown that lipid conjugation to oligodeoxynucleotides, polymers and small molecule drugs results in association not only with albumin, but also with lipoproteins, resulting in half-life prolongation and transport from administration sites via the lymphatics. Enhancing delivery into the lymph increases the efficacy of vaccines and therapeutics with lymphatic targets such as immunotherapies. In this study, the plasma PK, lymphatic uptake, and bioavailability of the glucagon-like peptide-1 (GLP-1) receptor agonist peptides, liraglutide (lipidated) and exenatide (non-lipidated), were investigated following subcutaneous (SC) administration to rats. As expected, liraglutide displayed an apparent prolonged plasma half-life (9.1 versus 1 h), delayed peak plasma concentrations and lower bioavailability (∼10 % versus ∼100 %) compared to exenatide after SC administration. The lymphatic uptake of both peptides was relatively low (<0.5 % of the dose) although lymph to plasma concentration ratios were greater than one for several early timepoints suggesting some direct uptake into lymph. The low lymphatic uptake may be due to the nature of the conjugated lipid (a single-chain C16 palmitic acid in liraglutide) but suggests that other peptides with similar lipid conjugations may also have relatively modest lymphatic uptake. If delivery to the lymph is desired, conjugation to more lipophilic moieties with higher albumin and/or lipoprotein binding efficiencies, such as diacylglycerols, may be appropriate.


Asunto(s)
Exenatida , Liraglutida , Péptidos , Ratas Sprague-Dawley , Animales , Exenatida/farmacocinética , Exenatida/administración & dosificación , Exenatida/farmacología , Liraglutida/farmacología , Liraglutida/farmacocinética , Liraglutida/administración & dosificación , Ratas , Masculino , Péptidos/farmacocinética , Péptidos/administración & dosificación , Lípidos/química , Semivida , Ponzoñas/farmacocinética , Ponzoñas/administración & dosificación , Disponibilidad Biológica , Distribución Tisular , Inyecciones Subcutáneas , Linfa/metabolismo , Linfa/efectos de los fármacos , Receptor del Péptido 1 Similar al Glucagón/agonistas , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Péptido 1 Similar al Glucagón/farmacocinética , Péptido 1 Similar al Glucagón/metabolismo , Sistema Linfático/metabolismo , Sistema Linfático/efectos de los fármacos , Hipoglucemiantes/farmacocinética , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/farmacología
9.
Expert Opin Pharmacother ; 25(7): 791-799, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38814590

RESUMEN

INTRODUCTION: Alzheimer's disease (AD) is a neurodegenerative condition characterized by progressive cognitive deterioration, functional impairments, and neuropsychiatric symptoms. Valiltramiprosate is a tramiprosate prodrug being investigated as a novel treatment for AD. AREAS COVERED: The online databases PubMed, Embase, Web of Science, Cochrane Library, and ClinicalTrials.gov were searched using the terms 'ALZ-801' or 'valiltramiprosate.' Alzheon press releases were reviewed for emerging clinical information. Valiltramiprosate is an oral, well-tolerated synthetic valine-conjugate prodrug of tramiprosate. Valiltramiprosate's active metabolite include tramiprosate and 3-sulfopropanoic acid. Proposed mechanism of action is multiligand binding to Aß42 which stabilizes amyloid monomers to prevent peptide aggregation and oligomerization. Pharmacokinetic studies show 52% oral bioavailability, rapid absorption, approximately 40% brain-drug exposure, and near complete renal clearance. Compared to tramiprosate, valiltramiprosate extends plasma tramiprosate half-life and improves interindividual pharmacokinetic variability. Interim analyses from valiltramiprosate's phase II biomarker trial show: (1) significant reductions in plasma p-tau181 and related AD fluid biomarkers; (2) brain structure preservation and reduced hippocampal atrophy by MRI; and (3) improvements on cognitive assessments at multiple timepoints. Its phase III clinical trial in ApoE ε4 homozygotes is near completion. EXPERT OPINION: Valiltramiprosate's clinical trial data show early indications of efficacy with potential disease modifying effect in AD.


Asunto(s)
Enfermedad de Alzheimer , Profármacos , Enfermedad de Alzheimer/tratamiento farmacológico , Humanos , Profármacos/farmacocinética , Animales , Péptidos beta-Amiloides/metabolismo , Ciclopropanos/uso terapéutico , Ciclopropanos/farmacocinética , Ciclopropanos/farmacología , Ciclopropanos/administración & dosificación , Combinación de Medicamentos , Fragmentos de Péptidos , Disponibilidad Biológica , Semivida , Valina/análogos & derivados , Valina/farmacocinética , Valina/administración & dosificación , Taurina/análogos & derivados
10.
J Pharmacol Toxicol Methods ; 127: 107513, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38729531

RESUMEN

BACKGROUND: Several novel synthetic cannabinoids, including methyl 2-(1-(4-fluorobenzyl)-1Hindazole-3-carboxamido)-3-methylbutanoate (AMB-FUBINACA), have recently surfaced on the illicit drug market. To determine the pharmacokinetic properties (half-life, volume of distribution, and clearance) of AMB-FUBINACA in rats plasma, a straightforward, quick, and highly sensitive analytical approach was developed. METHODS: Eighteen Wistar rats were divided into two groups: one control (saline vehicle) and one treatment group (AMB-FUBINACA at 50 mg/kg). Blood samples (400 µL) were withdrawn via catheters immediately before (t = 0) and at 30, 60, 90, 120, and 240 min following injection. Samples were collected into 1 mL tuberculin syringes, then transferred to 1.5 mL plastic tubes containing 5 µL of 1000 IU/mL K3-EDTA (Thomas Scientific). Place the EDTA tubes containing samples in a centrifuge and spin at 1000 g for 10 min at 4 °C. The top layer is the plasma fraction, which is decanted into cryovials and stored at -20 °C until analysis. The gas chromatography tandem mass spectrometry (GC-MS/MS) method was optimized and validated, combined with liquid-liquid extraction, to analyze AMB-FUBINACA in rat plasma. RESULTS: The research method successfully met the validation requirements set by the FDA, demonstrating selectivity and linear calibration curves within a concentration range of 0.5-1000 ng/ml. The correlation coefficient (r2) was determined to be 0.99, indicating a strong linear relationship. The analyte's limit of quantitation (LOQ) was determined to be 1-5 ng/mL. Subsequently, the method was successfully applied to investigate the pharmacokinetics of AMB-FUBINACA in rats' blood samples. Following oral administration, AMB-FUBINACA was rapidly absorbed, with a plasma half-life (t1/2) of 5.91 h, a volume of distribution (Vd) of 203.13 l, and a plasma clearance of 23.81122 L/h. CONCLUSION: These findings contribute to the understanding of AMB-FUBINACA's pharmacokinetics and pharmacodynamics.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas , Ratas Wistar , Espectrometría de Masas en Tándem , Animales , Ratas , Semivida , Cromatografía de Gases y Espectrometría de Masas/métodos , Masculino , Espectrometría de Masas en Tándem/métodos , Indazoles/farmacocinética , Indazoles/sangre
11.
Environ Pollut ; 355: 124212, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38810678

RESUMEN

In Australia, trifluralin is one of the commonly used herbicides to manage annual grasses and some broadleaf weeds. However, it may have some ecosystem impacts such as high toxicity to terrestrial and aquatic life, so it is vital to monitor the degradation of trifluralin for a considerable period for environmental safety. For risk assessment purposes, it is necessary to estimate the half-life of trifluralin, which is often evaluated using derived mathematical dissipation models. In the literature, bi-exponential (BEXP) and gamma models were suggested for modelling the dissipation of trifluralin in soil. Both models provide the half-life estimate without discussing the uncertainty of the estimate, which is a shortcoming in the literature. In this paper, we used simulation to illustrate the importance of estimate's uncertainty (standard error) and demonstrated a method to compute the standard error for the half-life estimate mathematically for kinetic dissipation models. Later, we evaluated the performance of the two suggested models using statistical indices. The computation of the half-life and the standard error of the half-life estimate were discussed. This allows us to describe the inference of the half-life parameter and determine whether the half-life estimates are significantly different against the co-variate (moisture) levels. We demonstrated the method to calculate the standard error of the half-life of trifluralin, which allows us to determine the statistical difference between the estimates. In this study, we found that the half-life of trifluralin in soil tends to increase with increasing moisture levels, and the half-life of trifluralin in soil with 100% moisture level is significantly greater than 40% and 70% moisture levels. Our findings suggest that soil moisture levels should be carefully considered before trifluralin application to minimize the non-target environmental damage.


Asunto(s)
Herbicidas , Contaminantes del Suelo , Suelo , Trifluralina , Trifluralina/química , Semivida , Contaminantes del Suelo/análisis , Suelo/química , Incertidumbre , Cinética , Modelos Químicos , Australia , Modelos Teóricos
12.
Environ Toxicol Pharmacol ; 108: 104471, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38763438

RESUMEN

In the study on Oreochromis niloticus, singular oral gavage of florfenicol (FFC) at 15 mg/kg biomass/day was conducted, mimicking approved aquaculture dosing. Samples of plasma, bile, muscle, intestine, skin, liver, kidney, gill, and brain tissues were collected at 0, 2, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, and 128 hours (h) after oral gavage. LC-MS/MS analysis revealed FFC concentrations peaked at 12.15 µg/mL in plasma and 77.92 µg/mL in bile, both at 24 hours. Elimination half-lives were 28.17 h (plasma) and 26.88 h (bile). The residues of FFC ranked muscle>intestine>skin>liver>kidney>gill. In contrast, the residues of florfenicol amine (FFA) ranked kidney>skin>liver>muscle>gill>intestine>brain, particularly notable in tropical summer conditions. The minimum inhibitory concentration of FFC was elucidated against several bacterial pathogens revealing its superior efficacy. Results highlight bile's crucial role in FFC elimination. Further investigation, especially during winter when fish susceptibility to infections rises, is warranted.


Asunto(s)
Antibacterianos , Cíclidos , Residuos de Medicamentos , Tianfenicol , Animales , Tianfenicol/análogos & derivados , Tianfenicol/farmacocinética , Tianfenicol/administración & dosificación , Antibacterianos/farmacocinética , Antibacterianos/administración & dosificación , Cíclidos/metabolismo , Bilis/química , Bilis/metabolismo , Administración Oral , Riñón/metabolismo , Pruebas de Sensibilidad Microbiana , Distribución Tisular , Hígado/metabolismo , Espectrometría de Masas en Tándem , Semivida
13.
Toxicol Lett ; 397: 103-116, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38703967

RESUMEN

Animal research continues to serve a critical role in the testing and development of medical countermeasures. The Göttingen minipig, developed for laboratory research, may provide many benefits for addressing research questions within chemical defense. Targeted development of the Göttingen minipig model could reduce reliance upon non-human primates, and improve study design, statistical power, and throughput to advance medical countermeasures for regulatory approval and fielding. In this vein, we completed foundational pharmacokinetics and physiological safety studies of intramuscularly administered atropine sulfate, pralidoxime chloride (2-PAM), and diazepam across a broad range of doses (1-6 autoinjector equivalent) using adult male Göttingen minipigs (n=11; n=4-8/study) surgically implanted with vascular access ports and telemetric devices to monitor cardiovascular, respiratory, arterial pressure, and temperature signals. Pharmacokinetic data were orderly and the concentration maximum mirrored available human data at comparably scaled doses clearly for atropine, moderately for 2-PAM, and poorly for diazepam. Time to peak concentration approximated 2, 7, and 20 min for atropine, 2-PAM, and diazepam, respectively, and the elimination half-life of these drugs approximated 2 hr (atropine), 3 hr (2-PAM), and 8 hr (diazepam). Atropine sulfate dose-dependently increased the magnitude and duration of tachycardia and decreased the PR and ST intervals (consistent with findings obtained from other species). Mild hypothermia was observed at the highest diazepam dose. Göttingen minipigs appear to provide a ready and appropriate large animal alternative to non-human primates, and further development and evaluation of novel nerve agent medical countermeasures and treatment strategies in this model are justified.


Asunto(s)
Atropina , Diazepam , Porcinos Enanos , Animales , Porcinos , Masculino , Diazepam/farmacocinética , Diazepam/farmacología , Atropina/farmacocinética , Atropina/farmacología , Agentes Nerviosos/farmacocinética , Agentes Nerviosos/toxicidad , Relación Dosis-Respuesta a Droga , Inyecciones Intramusculares , Semivida , Frecuencia Cardíaca/efectos de los fármacos , Telemetría , Modelos Animales , Compuestos de Pralidoxima
14.
Vet J ; 305: 106130, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38734403

RESUMEN

Tildipirosin is a macrolide antimicrobial. It is authorised for the treatment and prevention of respiratory disease in cattle and pigs. There are no data on its administration in crocodiles. Therefore, this study evaluated the disposition kinetics of tildipirosin after intravenous (dose: 2 mg/kg) and intramuscular (doses: 2 and 4 mg/kg) administration in two crocodilian species (estuarine and freshwater; n = 5). Tildipirosin plasma concentrations were quantified by a validated HPLC method. Plasma concentrations obtained at each extraction time were analysed by non-compartmental methods. In the estuarine and freshwater crocodiles, the apparent volumes of distribution of tildipirosin after intravenous administration were 0.36 ± 0.10 and 1.48 ± 0.26 L/kg, respectively. These values, suggesting poorer tissue distribution, were much lower than those obtained in mammals. There was complete bioavailability of tildipirosin after intramuscular route at a dose of 2 mg/kg; however, at a dose of 4 mg/kg the bioavailability decreased by about 20-25 %. Furthermore, the pharmacokinetics of tildipirosin were markedly different in the two crocodilian species. Considering a MIC of 0.5 µg/mL, the surrogate marker AUC0-24/MIC indicates that tildipirosin would greatly exceed the value of 65 h for both crocodile species and dose levels tested. This suggests that both doses (2 and 4 mg/kg) may provide a bactericidal effect. Therefore, based on the absence of adverse reactions following the administration of tildipirosin in both crocodilian species, and considering its favourable pharmacokinetic properties, tildipirosin may be useful in treating infections in these reptiles.


Asunto(s)
Caimanes y Cocodrilos , Tilosina , Animales , Tilosina/análogos & derivados , Tilosina/farmacocinética , Tilosina/administración & dosificación , Inyecciones Intramusculares/veterinaria , Antibacterianos/farmacocinética , Antibacterianos/administración & dosificación , Inyecciones Intravenosas/veterinaria , Agua Dulce , Semivida , Disponibilidad Biológica , Área Bajo la Curva
15.
Vet J ; 305: 106138, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38761957

RESUMEN

Abomasal ulcers are a significant concern in intensive animal farming due to their impact on animal health and productivity. While proton pump inhibitors (PPIs) such as pantoprazole (PTZ) show promise in treating these ulcers, data on PTZ's pharmacokinetics (PK) in adult goats and sheep are limited. This study aims to fill this gap by investigating and comparing PTZ's PK in these species following single intravenous (IV) and subcutaneous (SC) administrations. Five healthy male goats and sheep were included in the study. PTZ concentrations in plasma samples were determined using a validated analytical method. Non-compartmental analysis was conducted, and statistical comparisons were made between IV and SC administrations and between species. Sheep and goats showed similar systemic exposure levels regardless of the administration route. However, sheep had a shorter t1/2 due to a higher Vd compared to goats. Cl values were comparable in both species, with low extraction ratio values. There were no significant differences in Cmax and Tmax between the two species with regards to SC administration, and complete bioavailability was observed. The MAT exceeded the t1/2 in both species, indicating a potential flip-flop phenomenon. Considering the AUC as a predictor for drug efficacy, and observing no significant differences in systemic exposure between sheep and goats for any route of administration, dosage adjustment between the two species may not be necessary. In field settings, SC administration proves more practical, providing not only complete bioavailability but also a longer half-life compared to IV. Further studies are warranted to explore the PK/PD of PTZ in small ruminants with abomasal ulcers, to fully comprehend its therapeutic efficacy in such scenarios.


Asunto(s)
Cabras , Pantoprazol , Animales , Masculino , Ovinos , Pantoprazol/farmacocinética , Pantoprazol/administración & dosificación , Inyecciones Subcutáneas/veterinaria , Inyecciones Intravenosas/veterinaria , Inhibidores de la Bomba de Protones/farmacocinética , Inhibidores de la Bomba de Protones/administración & dosificación , Área Bajo la Curva , Disponibilidad Biológica , Semivida
16.
J Environ Sci Health B ; 59(7): 361-367, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38774990

RESUMEN

Field and lab experiments explored tetraniliprole dissipation in chili plants. A supervised trial in Devarayapuram village, Coimbatore, assessed the CO2 chili variety (December-March 2018-2019). Using the Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method and ultra-high-performance liquid chromatography (UHPLC), samples were collected up to 15 d post-application. Initial tetraniliprole deposits on chili fruits, 1-h post-spray, were 0.898 and 1.271 µg g-1 at single and double doses. Over 80% dissipated within 5 d, reaching below detection limits by day 7 and 10 for single and double doses, respectively. Transformation analysis favored first-order kinetics. Tetraniliprole half-life on chili fruit was 1.49 and 1.53 d at recommended and double doses. The safe waiting period was 4.16 and 5.04 d for 60 and 120 g a.i ha-1. This study provides insights into tetraniliprole dynamics in chili plants, crucial for effective pesticide management.


Asunto(s)
Capsicum , Capsicum/química , Frutas/química , Cromatografía Líquida de Alta Presión , Semivida , Residuos de Plaguicidas/análisis , Residuos de Plaguicidas/química , Contaminación de Alimentos/análisis , Cinética
17.
J Environ Sci Health B ; 59(7): 390-398, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38794798

RESUMEN

Despite the extensive exposure to imidacloprid residues in food plants, there has been little research on imidacloprid residues in amaranth. The dissipation trend and residue behavior of imidacloprid were evaluated to provide guidelines for imidacloprid application on amaranth under open field and greenhouse. The dissipation rate of imidacloprid in amaranth conformed to the first-order kinetic equation, and the half-lives of imidacloprid in amaranth ranged from 0.29 days in open field to 1.29 days in the greenhouse. After 7 and 14 days from the application of imidacloprid (pesticide dosage, 45 or 67.5 g a.i./ha), the amaranth under the open field and greenhouse growth could be consumed safely with average residues of 0.19 and 0.38 mg/kg, respectively. This result demonstrated that the cultivation has the dominant influence on imidacloprid residue, and the residue of imidacloprid in amaranth planting on open field was much lower than that in the greenhouse, indicating a significant difference in the pesticide residues between the two cultivations with a p-value less than 0.05.


Asunto(s)
Amaranthus , Insecticidas , Neonicotinoides , Nitrocompuestos , Residuos de Plaguicidas , Neonicotinoides/química , Neonicotinoides/análisis , Nitrocompuestos/química , Amaranthus/crecimiento & desarrollo , Amaranthus/química , Amaranthus/efectos de los fármacos , Residuos de Plaguicidas/análisis , Residuos de Plaguicidas/química , Insecticidas/química , Imidazoles/química , Imidazoles/análisis , Semivida , Agricultura/métodos , Contaminación de Alimentos/análisis , Cinética
18.
J Control Release ; 370: 468-478, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38697314

RESUMEN

A critical parameter during the development of protein therapeutics is to endow them with suitable pharmacokinetic and pharmacodynamic properties. Small protein drugs are quickly eliminated by kidney filtration, and in vivo half-life extension is therefore often desired. Here, different half-life extension technologies were studied where PAS polypeptides (PAS300, PAS600), XTEN polypeptides (XTEN288, XTEN576), and an albumin binding domain (ABD) were compared for half-life extension of an anti-human epidermal growth factor receptor 2 (HER2) affibody-drug conjugate. The results showed that extension with the PAS or XTEN polypeptides or the addition of the ABD lowered the affinity for HER2 to some extent but did not negatively affect the cytotoxic potential. The half-lives in mice ranged from 7.3 h for the construct including PAS300 to 11.6 h for the construct including PAS600. The highest absolute tumor uptake was found for the construct including the ABD, which was 60 to 160% higher than the PASylated or XTENylated constructs, even though it did not have the longest half-life (9.0 h). A comparison of the tumor-to-normal-organ ratios showed the best overall performance of the ABD-fused construct. In conclusion, PASylation, XTENylation, and the addition of an ABD are viable strategies for half-life extension of affibody-drug conjugates, with the best performance observed for the construct including the ABD.


Asunto(s)
Péptidos , Receptor ErbB-2 , Animales , Semivida , Receptor ErbB-2/metabolismo , Humanos , Línea Celular Tumoral , Péptidos/química , Péptidos/farmacocinética , Péptidos/administración & dosificación , Femenino , Ratones Desnudos , Albúminas/química , Proteínas Recombinantes de Fusión/farmacocinética , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/administración & dosificación , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacocinética , Antineoplásicos/química , Ratones , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Inmunoconjugados/farmacocinética , Inmunoconjugados/química , Inmunoconjugados/administración & dosificación , Ratones Endogámicos BALB C , Distribución Tisular
19.
Front Immunol ; 15: 1383123, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38799460

RESUMEN

Most drugs that target the complement system are designed to inhibit the complement pathway at either the proximal or terminal levels. The use of a natural complement regulator such as factor H (FH) could provide a superior treatment option by restoring the balance of an overactive complement system while preserving its normal physiological functions. Until now, the systemic treatment of complement-associated disorders with FH has been deemed unfeasible, primarily due to high production costs, risks related to FH purified from donors' blood, and the challenging expression of recombinant FH in different host systems. We recently demonstrated that a moss-based expression system can produce high yields of properly folded, fully functional, recombinant FH. However, the half-life of the initial variant (CPV-101) was relatively short. Here we show that the same polypeptide with modified glycosylation (CPV-104) achieves a pharmacokinetic profile comparable to that of native FH derived from human serum. The treatment of FH-deficient mice with CPV-104 significantly improved important efficacy parameters such as the normalization of serum C3 levels and the rapid degradation of C3 deposits in the kidney compared to treatment with CPV-101. Furthermore, CPV-104 showed comparable functionality to serum-derived FH in vitro, as well as similar performance in ex vivo assays involving samples from patients with atypical hemolytic uremic syndrome, C3 glomerulopathy and paroxysomal nocturnal hematuria. CPV-104 - the human FH analog expressed in moss - will therefore allow the treatment of complement-associated human diseases by rebalancing instead of inhibiting the complement cascade.


Asunto(s)
Factor H de Complemento , Humanos , Factor H de Complemento/metabolismo , Factor H de Complemento/genética , Animales , Ratones , Semivida , Polisacáridos/metabolismo , Bryopsida/metabolismo , Bryopsida/genética , Glicosilación , Proteínas Recombinantes , Ratones Noqueados , Ratones Endogámicos C57BL , Masculino
20.
Sci Rep ; 14(1): 10952, 2024 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-38740850

RESUMEN

It is recognized as a promising therapeutic strategy for cocaine use disorder to develop an efficient enzyme which can rapidly convert cocaine to physiologically inactive metabolites. We have designed and discovered a series of highly efficient cocaine hydrolases, including CocH5-Fc(M6) which is the currently known as the most efficient cocaine hydrolase with both the highest catalytic activity against (-)-cocaine and the longest biological half-life in rats. In the present study, we characterized the time courses of protein appearance, pH, structural integrity, and catalytic activity against cocaine in vitro and in vivo of a CocH5-Fc(M6) bulk drug substance produced in a bioreactor for its in vitro and in vivo stability after long-time storage under various temperatures (- 80, - 20, 4, 25, or 37 °C). Specifically, all the tested properties of the CocH5-Fc(M6) protein did not significantly change after the protein was stored at any of four temperatures including - 80, - 20, 4, and 25 °C for ~ 18 months. In comparison, at 37 °C, the protein was less stable, with a half-life of ~ 82 days for cocaine hydrolysis activity. Additionally, the in vivo studies further confirmed the linear elimination PK profile of CocH5-Fc(M6) with an elimination half-life of ~ 9 days. All the in vitro and in vivo data on the efficacy and stability of CocH5-Fc(M6) have consistently demonstrated that CocH5-Fc(M6) has the desired in vitro and in vivo stability as a promising therapeutic candidate for treatment of cocaine use disorder.


Asunto(s)
Cocaína , Estabilidad de Enzimas , Animales , Cocaína/metabolismo , Ratas , Hidrólisis , Concentración de Iones de Hidrógeno , Masculino , Semivida , Temperatura , Amidohidrolasas/metabolismo , Hidrolasas de Éster Carboxílico , Proteínas Recombinantes
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