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91.
Sandro M. Hirabara Alessandra Folador Jarlei Fiamoncini Rafael H. Lambertucci Carlos F. Rodrigues Marlene S. Rocha Julia Aikawa Ricardo K. Yamazaki Amanda R. Martins Alice C. Rodrigues Angelo R. Carpinelli Tania C. Pithon-Curi Luiz C. Fernandes Renata Gorjão Rui Curi 《The Journal of nutritional biochemistry》2013,24(6):1136-1145
We investigated the effect of fish oil supplementation for two consecutive generations on insulin sensitivity in rats. After the nursing period (21 days), female rats from the same prole were divided into two groups: (a) control group and (b) fish oil group. Female rats were supplemented with water (control) or fish oil at 1 g/kg body weight as a single bolus for 3 months. After this period, female rats were mated with male Wistar rats fed on a balanced chow diet (not supplemented). Female rats continued to receive supplementation throughout gestation and lactation periods. The same treatment was performed for the next two generations (G1 and G2). At 75 days of age, male offspring from G1 and G2 generations from both groups were used in the experiments. G1 rats did not present any difference with control rats. However, G2 rats presented reduction in glycemia and lipidemia and improvement in in vivo insulin sensitivity (model assessment of insulin resistance, insulin tolerance test) as well as in vitro insulin sensitivity in soleus muscle (glucose uptake and metabolism). This effect was associated with increased insulin-stimulated p38 MAP kinase phosphorylation and lower n-6/n-3 fatty acid ratio, but not with activation of proteins from insulin signaling (IR, IRS-1 and Akt). Global DNA methylation was decreased in liver but not in soleus muscle. These results suggest that long-term fish oil supplementation improves insulin sensitivity in association with increased insulin-stimulated p38 activation and decreased n-6:n-3 ratio in skeletal muscle and decreased global DNA methylation in liver. 相似文献
92.
Leonora C. Vilela Angelo R. Torillo Alice T. de Ocampo Ernesto J. del Rosario 《Bioscience, biotechnology, and biochemistry》2013,77(2):235-238
Cellulase was produced by Trichoderma viride in semisolid cultures of rice bran, rice straw and rice hulls. T. viride QM 9414 generally produced higher cellulolytic activity on CM-cellulose (Cx activity) using rice bran-rice hull mixture (2:1 w/w) as substrate compared to strains ITCC 1433 and D 4014. It showed higher Cx activity on rice bran-rice straw mixtures than on rice bran-rice hull mixtures. Maximal extraction of the enzyme from mold bran was obtained with 0.05 m sodium citrate buffer, pH 3.5. 相似文献
93.
Diego Corrêa Alves Carolina Viviana Minte-Vera Angelo Antonio Agostinho Edson Kiyoshi Okada Lilian Paula Vasconcelos 《Reviews in Fish Biology and Fisheries》2013,23(3):375-394
The mathematical and statistical advances in fitting stock assessment models enabled the emergence of the paradigm of “integrated analysis”, which fits all available data to a single model of population dynamics that traditionally has total catch as the only forcing function of the system. This approach, however, allowed us to include, in a flexible way, the effect of hydrological regime as an additional forcing function. We tried to achieve this flexibility by making the annual recruitment rates and spawning biomass adjustable to the attributes of the hydrological cycle data. Our models showed that these attributes are influential in the population dynamics of Brycon hilarii of the Northern Pantanal, and their inclusion in the models allowed best partial fits (which considered fits only to the data components length- and age-compositions, CPUE of juveniles and adults) than the Base-case (without hydrological attributes). The best partial fits where obtained when the attributes “delay of floods” and “intensity of floods” were forcing the spawning biomass and the annual recruitment respectively, indicating that these characteristics of the population may be influenced by specific attributes of the water level. The use of integrated modeling contributed with the advancement of population ecology knowledge of rheophilic fish. It is recommended that freshwater fisheries management be integrated into the hydrology management. 相似文献
94.
Knowledge of the mechanisms that regulate courtship and mating behavior in Psyttalia concolor (Szépligeti)–a koinobiont endophagous solitary parasitoid of the olive fruit fly, Bactrocera oleae (Rossi), and of other fruit flies–is essential to its mass rearing and management. Augmentative releases of P. concolor for olive fruit fly control started in the Mediterranean areas in the 1950s and still continue with limited success. We determined the influence of visual and chemical cues on courtship and mating behavior of this braconid and the possible effect of the mating status of males and females in the perception of these cues. Our results suggest that integration of visual and chemical stimuli are fundamental for mate location and courtship. Indeed, the optimal response of the male was achieved when physical and chemical cues were simultaneously presented and vision and olfaction worked synergistically. 相似文献
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97.
Giovanni Benelli Elisa Donati Donato Romano Giacomo Ragni Gabriella Bonsignori Cesare Stefanini Angelo Canale 《Insect Science》2016,23(6):869-880
Variations in male body size are known to affect inter‐ and intrasexual selection outcomes in a wide range of animals. In mating systems involving sexual signaling before mating, body size often acts as a key factor affecting signal strength and mate choice. We evaluated the effect of male size on courtship displays and mating success of the olive fruit fly, Bactrocera oleae (Diptera: Tephritidae). Wing vibrations performed during successful and unsuccessful courtships by large and small males were recorded by high‐speed videos and analyzed through frame‐by‐frame analysis. Mating success of large and small males was investigated. The effect of male–male competition on mating success was evaluated. Male body size affected both male courtship signals and mating outcomes. Successful males showed wing‐borne signals with high frequencies and short interpulse intervals. Wing vibrations displayed by successful large males during copulation attempt had higher frequencies over smaller males and unsuccessful large males. In no‐competition conditions, large males achieved higher mating success with respect to smaller ones. Allowing large and small males to compete for a female, large males achieve more mating success over smaller ones. Mate choice by females may be based on selection of the larger males, able to produce high‐frequency wing vibrations. Such traits may be indicative of “good genes,” which under sexual selection could means good social‐interaction genes, or a good competitive manipulator of conspecifics. 相似文献
98.
Hans Choi Daniel Conole Darcy J. Atkinson Olivia Laita Morgan Jay‐Smith Mario Angelo Pagano Giovanni Ribaudo Maurizio Cavalli Sergio Bova Brian Hopkins Margaret A. Brimble David Rennison 《化学与生物多样性》2016,13(6):762-775
Norbormide [5‐(α‐hydroxy‐α‐2‐pyridylbenzyl)‐7‐(α‐2‐pyridylbenzylidene)‐5‐norbornene‐2,3‐dicarboximide] (NRB), an existing but infrequently used rodenticide, is known to be uniquely toxic to rats but relatively harmless to other rodents and mammals. However, as an acute vasoactive, NRB has a rapid onset of action which makes it relatively unpalatable to rats, often leading to sublethal uptake and accompanying bait shyness. A series of NRB‐derived pro‐toxicants ( 3a – i , 4a – i , and 5a – i ) were prepared in an effort to ‘mask’ this acute response and improve both palatability and efficacy. Their synthesis, in vitro biological evaluation (vasocontractile response in rat vasculature, stability in selected rat media) and palatability/efficacy in Sprague–Dawley, wild Norway, and wild ship rats is described. Most notably, pro‐toxicant 3d was revealed to be free of all pre‐cleavage vasoconstrictory activity in rat caudal artery and was subsequently demonstrated to release NRB in the presence of rat blood, liver, and pancreatic enzymes. Moreover, it consistently displayed a high level of acceptance by rats in a two‐choice bait‐palatability and efficacy trial, with accompanying high mortality. On this evidence, fatty acid ester prodrugs would appear to offer a promising platform for the further development of NRB‐derived toxicants with enhanced palatability and efficacy profiles. 相似文献
99.
Retinal prosthesis technologies require that the visual system downstream of the retinal circuitry be capable of transmitting and elaborating visual signals. We studied the capability of plastic remodeling in late blind subjects implanted with the Argus II Retinal Prosthesis with psychophysics and functional MRI (fMRI). After surgery, six out of seven retinitis pigmentosa (RP) blind subjects were able to detect high-contrast stimuli using the prosthetic implant. However, direction discrimination to contrast modulated stimuli remained at chance level in all of them. No subject showed any improvement of contrast sensitivity in either eye when not using the Argus II. Before the implant, the Blood Oxygenation Level Dependent (BOLD) activity in V1 and the lateral geniculate nucleus (LGN) was very weak or absent. Surprisingly, after prolonged use of Argus II, BOLD responses to visual input were enhanced. This is, to our knowledge, the first study tracking the neural changes of visual areas in patients after retinal implant, revealing a capacity to respond to restored visual input even after years of deprivation. 相似文献
100.
Maurizio G. Paoletti Robert J. Blakemore Csaba Csuzdi Luca Dorigo Angelo Leandro Dreon Federico Gavinelli Francesca Lazzarini Nicola Manno Enzo Moretto David Porco Enrico Ruzzier Vladimiro Toniello Andrea Squartini Giuseppe Concheri Marina Zanardo Javier Alba-Tercedor 《PloS one》2016,11(3)
A new Italian earthworm morphologically close to the similarly large and anecic Eophila tellinii (Rosa, 1888) is described. Distribution of Eophila crodabepis sp. nov. extends over 750 km2 from East to West on the Asiago Plateau and Vittorio Veneto Hills, from North to South on mounts Belluno Prealps (Praderadego and Cesen), Asiago, Grappa and onto the Montello foothills. This range abuts that of Eophila tellinii in northern Friuli Venezia Giulia region. Known localities of both E. tellinii and E.crodabepis sp. nov. are mapped. mtDNA barcoding definitively separates the new western species from classical Eophila tellinii (Rosa, 1888). 相似文献