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1.
J Dairy Sci ; 102(4): 3071-3081, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30712927

RESUMO

Maternal milk is the primary source of nutrition for suckling mammals, and its yield and composition are important determinants of survival during the early neonatal period. The objective of this study was to examine whether parenteral administration of l-Arg to twin-bearing ewes, during mid to late pregnancy, influenced prepartum maternal mammary gland development and subsequent lactation performance in the early postpartum period (14 d). At 80 d of pregnancy, multiparous Romney ewes were housed indoors in group pens, split into 2 cohorts, and fed a lucerne-based pellet diet, formulated to meet 100% of National Research Council-recommended requirements for twin-bearing pregnant ewes, once a day. Cohort 1 was administered l-Arg (72.7 mg/kg of live weight via i.v, 3 times a day) from d 100 of pregnancy until d 140. At d 140, ewes were euthanized and maternal mammary tissues were collected for analysis of the biochemical indices total DNA, RNA, protein, protein synthetic efficiency (protein:RNA), cell size (protein:DNA), transcriptional efficiency (RNA:DNA), and the abundance of mammalian target of rapamycin (mTOR) and mTORSer2448 protein. Cohort 2 was administered an identical l-Arg regimen as cohort 1, but from d 100 until parturition. Milk was collected over a 14-d period (d 1, 4, 7, 10, and 14) to assess milk yield and composition. In cohort 1, total mammary DNA (cell number) tended to be higher in l-Arg ewes, with no change in total mammary RNA or protein content, biochemical indices of protein synthetic efficiency, cell size or transcriptional efficiency, or mTOR protein abundance or phosphorylation. In cohort 2, milk composition analysis from l-Arg ewes showed lower (d 7-14) milk somatic cell counts, greater crude protein percentage from d 7 to 10 but lower at d 14, and altered absolute concentrations of some free AA (d 7 and 14) compared with controls. We propose that parenteral administration of l-Arg during late pregnancy is associated with increased mammary gland cellular content and decreased somatic cell counts during early lactation.


Assuntos
Arginina/metabolismo , Leite/metabolismo , Ovinos/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Contagem de Células , Estudos de Coortes , Suplementos Nutricionais/análise , Feminino , Humanos , Lactação , Glândulas Mamárias Humanas/metabolismo , Leite/química , Gravidez , Fenômenos Fisiológicos da Nutrição Pré-Natal , Ovinos/genética , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Gêmeos
2.
Medchemcomm ; 8(10): 1993-2002, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30108718

RESUMO

In this work, we characterize nor-ß-lapachone-loaded (NßL-loaded) microcapsules prepared using an emulsification/solvent extraction technique. Features such as surface morphology, particle size distribution, zeta potential, optical absorption, Raman and Fourier transform infrared spectra, thermal analysis data, drug encapsulation efficiency, drug release kinetics and in vitro cytotoxicity were studied. Spherical microcapsules with a size of 1.03 ± 0.46 µm were produced with an encapsulation efficiency of approximately 19%. Quantum DFT calculations were also performed to estimate typical interaction energies between a single nor-ß-lapachone molecule and the surface of the microparticles. The NßL-loaded PLGA microcapsules exhibited a pronounced initial burst release. After the in vitro treatment with NßL-loaded microcapsules, a clear phagocytosis of the spheres was observed in a few minutes. The cytotoxic activity against a set of cancer cell lines was investigated.

3.
Molecules ; 21(7)2016 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-27384551

RESUMO

Prostate cancer is one of the most common malignant tumors in males and it has become a major worldwide public health problem. This study characterizes the encapsulation of Nor-ß-lapachone (NßL) in poly(d,l-lactide-co-glycolide) (PLGA) microcapsules and evaluates the cytotoxicity of the resulting drug-loaded system against metastatic prostate cancer cells. The microcapsules presented appropriate morphological features and the presence of drug molecules in the microcapsules was confirmed by different methods. Spherical microcapsules with a size range of 1.03 ± 0.46 µm were produced with an encapsulation efficiency of approximately 19%. Classical molecular dynamics calculations provided an estimate of the typical adsorption energies of NßL on PLGA. Finally, the cytotoxic activity of NßL against PC3M human prostate cancer cells was demonstrated to be significantly enhanced when delivered by PLGA microcapsules in comparison with the free drug.


Assuntos
Benzofuranos/administração & dosagem , Cápsulas , Preparações de Ação Retardada , Portadores de Fármacos , Ácido Láctico , Naftoquinonas/administração & dosagem , Ácido Poliglicólico , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Benzofuranos/química , Cápsulas/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Humanos , Concentração Inibidora 50 , Ácido Láctico/química , Masculino , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Naftoquinonas/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Neoplasias da Próstata , Análise Espectral Raman
4.
Front Biosci (Elite Ed) ; 8(2): 264-88, 2016 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-26709661

RESUMO

Increasing production efficiency with a high standard of animal welfare and respect for the environment is a goal of sheep farming systems. Substantial gains in productivity have been achieved through improved genetics, nutrition and management changes; however the survival and growth performance of multiple-born lambs still remains a problem. This is a significant production efficiency and animal well-being issue. There is a growing body of evidence that some amino acids have a role in regulating growth, reproduction and immunity through modulation of metabolic and cell signaling pathways. The purpose of this review is to provide an overview of what is currently known about the role of amino acids in sheep production and the potential for supplementation strategies to influence on-farm survival and growth of lambs.


Assuntos
Aminoácidos/fisiologia , Ovinos/fisiologia , Animais , Feminino , Placenta/fisiologia , Gravidez , Reprodução , Ovinos/embriologia , Ovinos/crescimento & desenvolvimento
5.
Molecules ; 19(4): 4145-56, 2014 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-24699154

RESUMO

UV-vis optical absorption spectra of the antitrypanocidal drug benznidazole solvated in water were measured for various concentrations. The spectra show a prominent peak around 3.80 eV, while deconvolution of the UV-vis optical absorption spectra revealed six bands centered at 3.60, 3.83, 4.15, 4.99, 5.60, and 5.76 eV. Benznidazole electronic transitions were obtained after density functional theory (DFT) calculations within the polarized continuum (PCM) model for water solvation. Molecular geometry optimizations were carried out, and the measured absorption peaks were related to specific molecular orbital transitions obtained within the time dependent DFT (TD-DFT) with excellent agreement between theory and experiment.


Assuntos
Nitroimidazóis/química , Tripanossomicidas/química , Teoria Quântica , Soluções , Espectrofotometria Ultravioleta , Termodinâmica , Água
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