RESUMEN
The present study investigated whether supplementation with different doses of cerium dioxide nanoparticles (CeO2 NPs) during in vitro maturation (IVM) of prepubertal ovine oocytes influenced their embryonic development in vitro. Cumulus-oocyte complexes derived from the ovaries of slaughtered prepubertal sheep underwent IVM with CeO2NPs (0, 44, 88 or 220µg mL-1). Matured oocytes were fertilised in vitro and zygotes were cultured for 7 days. The results demonstrated that CeO2NPs were internalised in the cumulus cells and not in the oocyte. The treatment with CeO2NPs did not affect nuclear maturation or intracellular levels of reactive oxygen species of the oocytes. The percentage of oocytes with regular chromatin configuration and cytoskeleton structures when treated with 44µg mL-1 CeO2NPs was similar to oocytes matured in the absence of CeO2NPs and significantly higher than those treated with 88 or 220µg mL-1 CeO2NPs. The relative quantification of transcripts in the cumulus cells of oocytes matured with 44µg mL-1 CeO2NPs showed a statistically lower mRNA abundance of BCL2-associated X protein (BAX), B-cell CLL/lymphoma 2 (BCL2) and superoxide dismutase 1 (SOD1) compared with the 0µg mL-1 CeO2 NPs group. A concentration of 44µg mL-1 CeO2NPs significantly increased the blastocyst yield and their total, inner cell mass and trophectoderm cell numbers, compared with the 0 and 220µg mL-1 groups. A low concentration of CeO2NPs in the maturation medium enhanced in vitro embryo production of prepubertal ovine oocytes.
Asunto(s)
Cerio/administración & dosificación , Desarrollo Embrionario/efectos de los fármacos , Nanopartículas/administración & dosificación , Oocitos/efectos de los fármacos , Animales , Células del Cúmulo/efectos de los fármacos , Células del Cúmulo/metabolismo , Citoesqueleto/metabolismo , Desarrollo Embrionario/fisiología , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Oocitos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , OvinosRESUMEN
Mesoporous aluminophosphate thin films with 3D cubic (Im3m) pore arrangement were synthesized for the first time. Thin films were templated with block copolymer nonionic templates Pluronic F127 and F108 and deposited on a glass substrate by dip-coating. In situ SAXS investigations show the formation of a highly ordered mesostructure upon the dip-coating process, which remains stable up to at least 670 K. A cubic mesostructure was observed also by TEM. Template removal process was monitored by TG and FT-IR. A transition from an amorphous aluminophosphate gel to a well-defined aluminophosphate framework was observed by MAS NMR.
Asunto(s)
Aluminio/química , Metales/química , Óxidos/química , Fosfatos/química , Compuestos de Aluminio/química , Vidrio , Espectroscopía de Resonancia Magnética , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Conformación Molecular , Poloxámero/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Propiedades de Superficie , TemperaturaRESUMEN
Fourier transform infrared spectroscopy has been applied to study the thermal stability of multilayer Langmuir-Schaefer (LS) films of lysozyme deposited on silicon substrates. The study has confirmed previous structural findings that the LS protein films have a high thermal stability that is extended in a lysozyme multilayer up to 200 degrees C. 2D infrared analysis has been used here to identify the correlated molecular species during thermal denaturation. Asynchronous 2D spectra have shown that the two components of water, fully and not fully hydrogen bonded, in the high-wavenumber range (2800-3600 cm-1) are negatively correlated with the amine stretching band at 3300 cm-1. On the grounds of the 2D spectra the FTIR spectra have been deconvoluted using three main components, two for water and one for the amine. This analysis has shown that, at the first drying stage, up to 100 degrees C, only the water that is not fully hydrogen bonded is removed. Moreover, the amine intensity band does not change up to 200 degrees C, the temperature at which the structural stability of the multilayer lysozyme films ceases.
Asunto(s)
Muramidasa/química , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Adsorción , Aminas , Estabilidad de Enzimas , Enlace de Hidrógeno , Desnaturalización Proteica , Silicio , AguaRESUMEN
Mesoporous films containing organic or biological functions within an organised array of cavities are produced by combining sol-gel, self-assembly of supramolecular templates and surface chemistry. This paper reviews the essential physics and chemical concepts behind the synthesis of these complex multifunctional materials.
Asunto(s)
Productos Biológicos/química , Compuestos Inorgánicos/química , Compuestos Orgánicos/química , Polímeros/química , Productos Biológicos/síntesis química , Compuestos Inorgánicos/síntesis química , Compuestos Orgánicos/síntesis química , Docilidad , Polímeros/síntesis química , Porosidad , Propiedades de SuperficieRESUMEN
Previous work showed that females of the European tarnished plant bug, Lygus rugulipennis Poppius (Heteroptera: Miridae), produced three chemicals, hexyl butyrate, (E)-2-hexenyl butyrate, and (E)-4-oxo-2-hexenal, and that these were suspected to be components of the female sex pheromone. In field experiments, traps baited with blends of these chemicals dispensed from polyethylene vials and sachets failed to catch significant numbers of males. Here, we report more recent field experiments in which the chemicals were released from glass microcapillary tubes. A blend of hexyl butyrate and (E)-4-oxo-2-hexenal was significantly attractive to male L. rugulipennis. In addition, whereas the mixture of all three components attracted fewer L. rugulipennis males, this tertiary blend captured significantly greater numbers of males of the congeneric species Lygus pratensis than the binary mixture. The possible reasons for the success of the microcapillaries compared with other dispensers are discussed.
Asunto(s)
Heterópteros/efectos de los fármacos , Atractivos Sexuales/farmacología , Conducta Sexual Animal/efectos de los fármacos , Animales , Butiratos/química , Butiratos/farmacología , Femenino , Heterópteros/química , Heterópteros/fisiología , Hexobarbital/química , Hexobarbital/farmacología , Masculino , Atractivos Sexuales/química , Factores de TiempoRESUMEN
The European tarnished plant bug, Lygus rugulipennis, is an important pest of agricultural and horticultural crops throughout Europe. Adult male L. rugulipennis were previously shown to be attracted to traps baited with live virgin females, which suggests the females produce a sex pheromone. Volatiles produced by virgin female L. rugulipennis were shown to contain three components, hexyl butyrate, (E)-2-hexenyl butyrate, and (E)-4-oxo-2-hexenal which elicited electroantennographic (EAG) responses from males in analyses by linked gas chromatography-electroantennography (GC-EAG). They were produced in 1.5:1:0.08 ratio, respectively, by single females. Collections from 1, 2, or 4 virgin females showed the proportions of hexyl butyrate and (E)-4-oxo-2-hexenal to increase relative to that of (E)-2-hexenyl butyrate with increasing number of females. Although these compounds were found in body extracts of both male and female L. rugulipennis, they were not detected in volatiles released by virgin males. EAG dose-response studies showed that both males and females responded to these chemicals with minimal differences in sensitivity between the sexes or to the three components, except that males were more responsive than females to (E)-4-oxo-2-hexenal at the two highest doses tested. Release rates of the compounds from rubber septa, polyethylene vials, and polyethylene sachets were measured under laboratory conditions. Four field tests were carried out using sticky traps baited with all possible binary and tertiary combinations of the three chemicals using different combinations of dispensing systems. Catches of male L. rugulipennis in baited traps were similar to those in unbaited traps. Significantly fewer females were caught on traps baited with blends containing hexyl butyrate than on traps without hexyl butyrate or unbaited traps in one test and overall. The roles of the three compounds and possible reasons for their failure to attract males are discussed.
Asunto(s)
Hemípteros/química , Feromonas/química , Aldehídos/química , Animales , Butiratos/química , Cromatografía de Gases , Relación Dosis-Respuesta a Droga , Femenino , Hemípteros/metabolismo , Masculino , Feromonas/análisis , Conducta Sexual Animal , VolatilizaciónRESUMEN
The strawberry blossom weevil, Anthonomus rubi, is a major pest of strawberries in the United Kingdom and continental Europe. As part of a project to develop noninsecticidal control methods, the pheromone system of this species was investigated. Comparison of volatiles produced by field-collected, overwintering individuals of each sex led to identification of three male-specific compounds--(Z)-2-(3,3-dimethylcyclohexylidene)ethanol, (cis)-1-methyl-2-(1-methylethenyl)cyclobutaneethanol, and 2-(1-methylethenyl)-5-methyl-4-hexen-1-ol (lavandulol)--in amounts of 6.1, 1.2, and 0.82 microg/day/ male. The first two compounds are components of the aggregation pheromone of the boll weevil, Anthonomus grandis, grandlure II and grandlure I, respectively. Grandlure I was the (1R,2S)-(+) enantiomer and lavandulol was a single enantiomer, although the absolute configuration was not determined. Trace amounts of the other two grandlure components (Z)-(3,3-dimethylcyclohexylidene)acetaldehyde (grandlure III) and (E)-(3,3-dimethylcyclohexylidene)acetaldehyde (grandlure IV) were also detected. (E,E)-1-(1-Methylethyl)-4-methylene-8-methyl-2,7-cyclo-decadiene (germacrene-D), a known volatile from strawberry plants, Fragaria ananassa, was collected in increased amounts in the presence of pheromone-producing weevils. Male weevils only produced pheromone on F. ananassa and not on scented mayweed, Matracaria recutita, or cow parsley, Anthriscus sylvestris, although these are known food sources. In field trials using various combinations of synthetic grandlures I, II, III, and IV and lavandulol, significantly more weevils were caught in traps baited with blends containing grandlure I and II and lavandulol than in those baited with blends without lavandulol or unbaited controls. Addition of grandlure III and IV had no significant effect on attractiveness. Horizontal sticky traps were found to be more effective than vertical sticky traps or standard boll weevil traps. In mid-season females predominated in the catches, but later more males than females were trapped.