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1.
Reprod Domest Anim ; 58(10): 1368-1378, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37605306

RESUMEN

Although oocyte in vitro maturation (IVM) is routinely used for in vitro embryo production in mice and rats, its use in wild rodents remains unexplored. Evidence suggests that hormone and growth factor supplementation influence oocyte meiotic resumption. This study evaluated the synergistic effects of follicle-stimulating hormone (FSH) and epidermal growth factor (EGF) on the IVM and parthenogenetic development of red-rumped agouti oocytes. Initially, we evaluated the IVM rates, mature oocyte quality, oocyte morphometry, and early embryonic development during IVM in the presence of 10, 50, and 75 mIU/mL FSH. No differences among the FSH concentrations were observed for IVM rates, oocyte morphometry, cumulus cell expansion, and viability. Although oocytes matured with 50 mIU/mL FSH showed a higher rate of cumulus expansion index (CEI), only oocytes matured with 10 mIU/mL FSH resulted in morulae after chemical activation (7.9% ± 4.2%). Thus, 10 mIU/mL FSH was used for further experiments. We subsequently evaluated the synergistic effects of 10, 50, and 100 ng/mL EGF and 10 mIU/mL FSH on the same parameters. No differences among the groups were observed in IVM rates, oocyte morphometry, and cumulus viability. Nevertheless, FSH with 10 ng/mL EGF showed a CEI superior to that of the other groups. Furthermore, oocytes matured with FSH alone or with both FSH and 10 or 50 ng/mL EGF developed morulae after activation (5.8%-8.3%). In conclusion, oocytes matured with 10 mIU/mL FSH and 10 ng/mL EGF are recommended for use in red-rumped agouti oocyte IVM, as they positively influence embryonic development.

2.
Mol Pharm ; 14(6): 2099-2115, 2017 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-28475834

RESUMEN

A monolithic drug-in-NLC-in-adhesive transdermal patch, with a novel design, was developed for codelivery of olanzapine (OL) and simvastatin (SV). Nanostructured lipid carriers (NLC) and enhancers were used as passive strategies, while the pretreatment of the skin with Dermaroller was tested as an active approach. The formulation was optimized for composition in a quality by design basis, in terms of enhancer and adhesive, with focus on permeation behavior, adhesion properties, and cytotoxicity. Propylene glycol promoted the best permeation rate for both drugs, with enhancement ratios of 8.1 and 12.9 for OL and SV, respectively, relative to the corresponding Combo-NLC patch without enhancer. Molecular dynamics results provided a rationale for these observations. The adhesive type displayed an important role in skin permeation, reinforced by the presence of the enhancer. Finally, Dermaroller pretreatment did not promote a significant improvement in permeation, which highlights the role of the combination of NLC with chemical enhancer in the transdermal patch as the main driving force in the process. It is also observed that NLC are able to reduce cytotoxicity, especially that associated with SV. This work provides a promising in vitro-in silico basis for a future in vivo development.


Asunto(s)
Adhesivos/química , Lípidos/química , Nanopartículas/química , Nanoestructuras/química , Administración Cutánea , Benzodiazepinas/administración & dosificación , Benzodiazepinas/química , Línea Celular , Portadores de Fármacos/química , Humanos , Microscopía Electroquímica de Rastreo , Simulación de Dinámica Molecular , Olanzapina , Simvastatina/análisis , Simvastatina/química
3.
Int J Pharm ; 515(1-2): 69-83, 2016 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-27667757

RESUMEN

Lipid nanoparticles and their multiple designs have been considered appealing nanocarrier systems. Bringing the benefits of these nanosystems together with conventional coating technology clearly results in product differentiation. This work aimed at developing an innovative solid dosage form for oral administration based on tableting nanostructured lipid carriers (NLC), coated with conventional polymer agents. NLC dispersions co-encapsulating olanzapine and simvastatin (Combo-NLC) were produced by high pressure homogenization, and evaluated in terms of scalability, drying procedure, tableting and performance from in vitro release, cytotoxicity and intestinal permeability stand points. Factorial design indicated that the scaling-up of the NLC production is clearly feasible. Spray-drying was the method selected to obtain dry particles, not only because it consists of a single step procedure, but also because it facilitates the coating process of NLC with different polymers. Modified NLC formulations with the polymers allowed obtaining distinct release mechanisms, comprising immediate, delayed and prolonged release. Sureteric:Combo-NLC provided a low cytotoxicity profile, along with a ca. 12-fold OL/3-fold SV higher intestinal permeability, compared to those obtained with commercial tablets. Such findings can be ascribed to drug protection and control over release promoted by NLC, supporting them as a versatile platform able to be modified according to the intended needs.


Asunto(s)
Absorción Intestinal/efectos de los fármacos , Lípidos/química , Nanopartículas/química , Administración Oral , Benzodiazepinas/química , Benzodiazepinas/metabolismo , Química Farmacéutica/métodos , Desecación/métodos , Portadores de Fármacos/química , Excipientes/química , Nanoestructuras/química , Olanzapina , Tamaño de la Partícula , Permeabilidad , Polímeros/química , Simvastatina/química , Simvastatina/metabolismo
4.
Rev Gastroenterol Mex ; 81(1): 28-34, 2016.
Artículo en Inglés, Español | MEDLINE | ID: mdl-26780984

RESUMEN

BACKGROUND: The different forms of lubrication are among the most simple, accessible, and economic techniques that have been implemented for improving the diagnostic performance of colonoscopy. AIM: To determine whether the use of oil improved the number of complete colonoscopies, facilitated the procedure, reduced pain, or improved the study's diagnostic performance, compared with the conventional lubrication technique. PATIENTS AND METHODS: One hundred and seventy-five patients referred for colonoscopy were alternately allocated to receive treatment with the standard lubrication method with chlorhexidine gel (group 1) or lubrication with corn oil administered through the working channel (group II). The number of complete colonoscopies, the length of time needed to reach the cecum, the degree of difficulty estimated by the endoscopist and the assistant, the level of pain at the end of the study estimated by the patient, and the endoscopic findings were all determined. RESULTS: Eighty-eight patients made up group I and 87 made up group II. No statistically significant differences were found between the two groups in relation to general characteristics, the number of complete colonoscopies (93 vs. 97%, respectively), the time needed to reach the cecum (8:00 vs. 8:41min, respectively), the level of pain at the end of the study, or the detection of polyps. The degree of difficulty was slightly lower in group II, but with no statistical significance. CONCLUSIONS: Lubrication with oil during colonoscopy did not improve the number of complete colonoscopies, did not facilitate the study, nor did it reduce pain or increase the diagnostic performance of the study, when compared with the conventional technique.


Asunto(s)
Colonoscopía/métodos , Aceite de Maíz , Lubrificación/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Clorhexidina , Pólipos del Colon/diagnóstico , Desinfectantes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dolor/epidemiología , Satisfacción del Paciente , Adulto Joven
5.
J Control Release ; 167(3): 301-14, 2013 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-23454133

RESUMEN

Co-encapsulation of drugs directed at commonly associated diseases provides a convenient means for administration, especially if transdermally delivered. In this work, a comprehensive study for the co-encapsulation of drugs with a differential lipophilicity, olanzapine and simvastatin, and their transdermal delivery in a formulation containing nanostructured lipid carriers (NLC) is presented. Focus is given to the evaluation of a strategy in which NLC and chemical permeation enhancers are combined. It comprises in vitro, in silico and cellular viability approaches. The optimization and rationalization of the systems are carried out using a two-step factorial design. It is shown that the external medium in the NLC dispersion strongly influences permeation. It is also seen that the use of NLC determines a synergistic effect with selected permeation enhancers, thus promoting marked flux enhancement ratios (48 and 21, respectively for olanzapine and simvastatin) relative to the drugs in solution. The developed formulations can be considered non-irritant. A correlation between enhancer positioning in a lipid bilayer, partially governed by a H-bonding phenomenon, and enhancement effect is suggested from molecular dynamics studies and experimental observations.


Asunto(s)
Antipsicóticos/administración & dosificación , Benzodiazepinas/administración & dosificación , Portadores de Fármacos/administración & dosificación , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Nanoestructuras/administración & dosificación , Simvastatina/administración & dosificación , Administración Cutánea , Animales , Antipsicóticos/química , Benzodiazepinas/química , Línea Celular , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Portadores de Fármacos/química , Diseño de Fármacos , Fibroblastos , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/química , Técnicas In Vitro , Simulación de Dinámica Molecular , Nanoestructuras/química , Olanzapina , Permeabilidad , Simvastatina/química , Piel/metabolismo , Absorción Cutánea , Porcinos , Triglicéridos/química
6.
Comp Cytogenet ; 6(2): 163-81, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-24260660

RESUMEN

Cichlids represent one of the most species-rich families of fishes and have attracted the attention of evolutionary biologists due to the rapid radiation occurring in some groups and the importance of some species in the world aquaculture. Cytogenetic analysis was conducted in 10 cichlid species from the Araguaia River, Amazon Basin, Brazil. The chromosome number was 2n=48 for all analyzed species except for Laetacara araguaiae Ottoni et Costa, 2009 (2n=44). Chromosomal polymorphism was detected only in Geophagus proximus (Castelnau, 1855), which exhibits an extra large submetacentric and and a dot-like chromosomes. Moreover, the C-banding revealed a general pericentromeric heterochromatic pattern and some additional blocks for some species. The heterochromatic blocks corresponding to AgNOR bearing regions were observed in all species and also corresponded to CMA3 positive blocks, which were observed in terminal regions. Besides the general conserved chromosomal and heterochromatin patterns for South American cichlids, the presence of GC-rich heterochromatin was quite different in the species Biotodoma cupido (Heckel, 1840), Geophagus proximus, Retroculus lapidifer (Castelnau, 1855), Crenicichla strigata Günther, 1862 and Heros efasciatus Heckel, 1840. The results suggest that independent events of heterochromatin modification occurred during chromosome evolution in the group, regardless of the conservation of macro-chromosomal structure.

7.
J Fish Biol ; 78(4): 1239-48, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21463318

RESUMEN

Cytogenetic markers were used to compare the karyotypes of an isolated population of Hoplias malabaricus with others previously described. The results revealed peculiar characteristics that indicate a new independent evolutionary unit within the H. malabaricus complex.


Asunto(s)
Cromosomas/genética , Análisis Citogenético , Peces/genética , Variación Genética , Animales , Femenino , Cariotipificación , Masculino , Polimorfismo Genético
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