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1.
Poult Sci ; 102(5): 102607, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36933527

RESUMO

Modern poultry production relies on an ability to prevent and mitigate challenges to bird health, while maintaining a productive bird. A number of different classes of biologics-based feed additives exist, and many have been tested individually for their impacts on poultry health and performance. Fewer studies have examined the combinations of different classes of products. In this study, we examined the use of a well-established postbiotic feed additive (Original XPC, Diamond V) on turkey performance, with and without the addition of a proprietary saponin-based feed additive. This was accomplished in an 18-wk pen trial utilizing 22 pen replicates per treatment across 3 treatments (control, postbiotic, and postbiotic plus saponin). Significant differences in body weight were identified at wk 12 and 15 of age, with the postbiotic plus saponin treatment group resulting in heavier birds at both timepoints. Significant differences in feed conversion ratio were observed from 0 to 18 wk of age, with the postbiotic alone having improved FCR compared with the control group. No significant differences were observed for livability or feed intake. This study demonstrates that a combination of a postbiotic plus saponin may exert additive effects on the growth of the turkey.


Assuntos
Suplementos Nutricionais , Saponinas , Animais , Dieta/veterinária , Galinhas , Perus , Ração Animal/análise
2.
Mol Pharm ; 16(5): 1917-1928, 2019 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-30973741

RESUMO

Drug delivery vehicles can improve the functional efficacy of existing antimicrobial therapies by improving biodistribution and targeting. A critical property of such nanomedicine formulations is their ability to control the release kinetics of their payloads. The combination of (and interactions among) polymer, drug, and nanoparticle properties gives rise to nonlinear behavioral relationships and large data space. These factors complicate both first-principles modeling and screening of nanomedicine formulations. Predictive analytics may offer a more efficient approach toward the rational design of nanomedicines by identifying key descriptors and correlating them to nanoparticle release behavior. In this work, antibiotic release kinetics data were generated from polyanhydride nanoparticle formulations with varying copolymer compositions, encapsulated drug type, and drug loading. Four antibiotics, doxycycline, rifampicin, chloramphenicol, and pyrazinamide, were used. Linear manifold learning methods were used to relate drug release properties with polymer, drug, and nanoparticle properties, and key descriptors were identified that are highly correlated with release properties. However, these linear methods could not predict release behavior. Nonlinear multivariate modeling based on graph theory was then used to deconvolute the governing relationships between these properties, and predictive models were generated to rapidly screen lead nanomedicine formulations with desirable release properties with minimal nanoparticle characterization. Release kinetics predictions of two drugs containing atoms not included in the model showed good agreement with experimental results, validating the model and indicating its potential to virtually explore new polymer and drug pairs not included in the training data set. The models were shown to be robust after the inclusion of these new formulations, in that the new inclusions did not significantly change model regression. This approach provides the first step toward the development of a framework that can be used to rationally design nanomedicine formulations by selecting the appropriate carrier for a drug payload to program desirable release kinetics.


Assuntos
Ciência de Dados/métodos , Desenho de Fármacos , Liberação Controlada de Fármacos , Modelos Biológicos , Nanopartículas/química , Antibacterianos/farmacocinética , Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Bases de Dados de Produtos Farmacêuticos , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos , Humanos , Nanomedicina , Polianidridos/química , Polímeros/química , Distribuição Tecidual
3.
J Control Release ; 294: 288-297, 2019 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-30572034

RESUMO

New therapies are needed to treat chronic bacterial diseases and intracellular pathogens, in particular, are very difficult to manage. The use of nanotherapeutics represents an approach to exploit size and charge of biological membranes to overcome barriers for treatment of intracellular pathogens including Brucella melitensis. In this work, polyanhydride nanoparticles comprised of copolymers of sebacic acid, 1,6-bis(p-carboxyphenoxy)hexane, and 1,8-bis(p-carboxyphenoxy)-3,6-dioxaoctane were synthesized to encapsulate antimicrobial compounds doxycycline and rifampicin. The nanoparticles demonstrated sustained release of rifampicin for a week with the antimicrobial activity peaking at 72 h and lasting up to a week. Treatment of B. melitensis infected macrophages with rifampicin-containing nanoparticles rapidly eliminated viable intracellular bacteria following 48 h of treatment and pretreatment with the nano-formulations prevented intracellular infection in contrast to soluble drug controls. Treatment of infected BALB/c mice with a nanoparticle cocktail containing doxycycline and rifampicin for five days decreased bacterial burden by three log10 in the liver. Extended release of antibiotics was demonstrated in vivo by treating B. melitensis infected mice with the standard therapy of daily 0.5 mg doxycycline dose or single 0.5 mg doxycycline-encapsulated nanoparticles delivered once a week. After 3 weeks, bacterial counts in spleen and liver were statistically equal between animals treated with the weekly nano-formulation and daily soluble drug, representing a seven-fold dose sparing. Altogether, these results demonstrated that the use of nanotherapeutics was successful at increasing antimicrobial efficacy and improving in vivo activity through a combination of intracellular delivery, dose sparing, and extended release in treating chronic bacterial infections. This platform technology can also provide benefits for drug delivery against other chronic intracellular bacterial pathogens, including Mycobacterium and Burkholderia species, including treatments against antibiotic-resistant infections.


Assuntos
Antibacterianos/administração & dosagem , Brucella melitensis , Brucelose/tratamento farmacológico , Doxiciclina/administração & dosagem , Nanopartículas/administração & dosagem , Rifampina/administração & dosagem , Animais , Antibacterianos/química , Preparações de Ação Retardada , Doxiciclina/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Nanomedicina , Nanopartículas/química , Células RAW 264.7 , Rifampina/química
4.
PLoS Negl Trop Dis ; 9(10): e0004173, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26496201

RESUMO

Filarial diseases represent a significant social and economic burden to over 120 million people worldwide and are caused by endoparasites that require the presence of symbiotic bacteria of the genus Wolbachia for fertility and viability of the host parasite. Targeting Wolbachia for elimination is a therapeutic approach that shows promise in the treatment of onchocerciasis and lymphatic filariasis. Here we demonstrate the use of a biodegradable polyanhydride nanoparticle-based platform for the co-delivery of the antibiotic doxycycline with the antiparasitic drug, ivermectin, to reduce microfilarial burden and rapidly kill adult worms. When doxycycline and ivermectin were co-delivered within polyanhydride nanoparticles, effective killing of adult female Brugia malayi filarial worms was achieved with approximately 4,000-fold reduction in the amount of drug used. Additionally the time to death of the macrofilaria was also significantly reduced (five-fold) when the anti-filarial drug cocktail was delivered within polyanhydride nanoparticles. We hypothesize that the mechanism behind this dramatically enhanced killing of the macrofilaria is the ability of the polyanhydride nanoparticles to behave as a Trojan horse and penetrate the cuticle, bypassing excretory pumps of B. malayi, and effectively deliver drug directly to both the worm and Wolbachia at high enough microenvironmental concentrations to cause death. These provocative findings may have significant consequences for the reduction in the amount of drug and the length of treatment required for filarial infections in terms of patient compliance and reduced cost of treatment.


Assuntos
Anti-Helmínticos/farmacologia , Antibacterianos/farmacologia , Brugia Malayi/efeitos dos fármacos , Brugia Malayi/fisiologia , Portadores de Fármacos/metabolismo , Nanopartículas/metabolismo , Polianidridos/metabolismo , Animais , Doxiciclina/farmacologia , Ivermectina/farmacologia , Locomoção/efeitos dos fármacos , Testes de Sensibilidade Parasitária , Análise de Sobrevida
5.
J Control Release ; 219: 548-559, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26315817

RESUMO

Complex biological barriers are major obstacles for preventing and treating disease. Nanocarriers are designed to overcome such obstacles by enhancing drug delivery through physiochemical barriers and improving therapeutic indices. This review critically examines both biological barriers and nanocarrier payloads for a variety of drug delivery applications. A spectrum of nanocarriers is discussed that have been successfully developed for improving tissue penetration for preventing or treating a range of infectious, inflammatory, and degenerative diseases.


Assuntos
Portadores de Fármacos/administração & dosagem , Nanopartículas/administração & dosagem , Exoesqueleto/metabolismo , Animais , Encéfalo/metabolismo , Neoplasias/metabolismo
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