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131.
The maned wolf (Chrysocyon brachyurus, Illiger, 1815, Canidae) is a threatened species that inhabits the cerrados of Brazil, Argentina, Peru, Bolivia, Paraguay, and Uruguay. Captive maned wolves could be potentially used in reintroduction programs for species conservation; however, it is necessary that their behavior and cognitive abilities are conserved. Environmental enrichment is a tool used to stimulate captive animals and maintain a natural behavioral repertoire. To compare the variation of captive maned wolves' behavioral responses to environmental enrichment, we studied three maned wolves held by Belo Horizonte Zoo, Brazil. Foraging, interspecific, and intraspecific stimuli were offered to the animals and their responses were compared with a baseline and postenrichment treatments. The test was used to help in choosing which one of the three individuals would participate in a reintroduction project. The results showed that stimuli type did influence the animal's responses, and that individually wolves responded differently to foraging, interspecific, and intraspecific enrichment items (P80.05 for some behaviors in each enrichment category). The individual's personality seemed to influence their behavioral responses, with animals showing bold and shy responses, and this trait should be considered during decision makings for reintroduction. 相似文献
132.
MK Hagen A Ludke AS Araujo RH Mendes TG Fernandes JM Mandarino S Llesuy E Vogt de Jong A Belló-Klein 《Canadian journal of physiology and pharmacology》2012,90(8):1095-1103
This study analyzed and compared the content of isoflavones in 2 soy products, the effectiveness of isoflavones as antioxidants, in vitro, and demonstrated the antioxidant effect of a soy diet in rats with myocardial infarction (MI). Isoflavone content was analyzed in soybean hypocotyl (SH) and isolated soy protein (ISP). The quality (TAR) and quantity (TRAP) of antioxidants present in the samples was quantified. The amount of daidzin was higher in SH (9 times) and genistein in ISP (5 times). SH presented a 3-fold increase in TAR, while both products exhibited same TRAP. The rats were fed an ISP diet for 9 weeks. Animals were distributed among 6 treatment groups: (i) Sham Casein; (ii) Infarct Casein < 25%; (iii) Infarct Casein > 25%; (iv) Sham Soy; (v) Infarct Soy < 25%; and (vi) Infarct Soy > 25%. MI was induced 5 weeks after the commencement of the diets. Lipid peroxidation (LPO), antioxidant enzyme activity, and levels of nitrites/nitrates were determined in blood. Rats receiving the ISP diet demonstrated increased activity of antioxidant enzyme activity and nitrite/nitrate content. In addition, the increase in LPO seen in rats subjected to MI was significantly mitigated when the ISP diet was given. These findings suggest a nutritional approach of using a soy-based diet for the prevention of oxidative-stress-related diseases such as heart failure. 相似文献
133.
Mascarin GM Duarte Vda S Brandão MM Delalibera I 《Journal of invertebrate pathology》2012,110(3):401-404
Occurrence of Zoophthora radicans infecting nymphs and adults of Thaumastocoris peregrinus Carpintero and Dellape, 2006 is reported in Brazil. This is a new record of host for this fungal species and the first fungal pathogen associated with this pest worldwide. Infection of Z. radicans on T. peregrinus populations on commercial Eucalyptus plantation (Eucalyptus spp.) reached up to 100%, and low insect densities were associated with high levels of fungal infection in three out of seven plots. This pathogen seems to be virulent against T. peregrinus and may play an important role in population regulations of this invasive pest through naturally induced epizootics. 相似文献
134.
135.
Leonardo Soriano Francisco de Assis Alves Mour?o Filho Luis Eduardo Aranha Camargo Mariangela Cristofani-Yaly Rodrigo Rocha Latado Camila de Andrade Pacheco Fernando Alves de Azevedo Beatriz Madalena Januzzi Mendes 《Plant Cell, Tissue and Organ Culture》2012,111(3):385-392
Protoplast fusion between sweet orange and mandarin/mandarin hybrids scion cultivars was performed following the model ??diploid embryogenic callus protoplast?+?diploid mesophyll-derived protoplast??. Protoplasts were isolated from embryogenic calli of ??Pera?? and ??Westin?? sweet orange cultivars (Citrus sinensis) and from young leaves of ??Fremont??, Nules??, and ??Thomas?? mandarins (C. reticulata), and ??Nova?? tangelo [C. reticulata?×?(C. paradisi?×?C. reticulata)]. The regenerated plants were characterized based on their leaf morphology (thickness), ploidy level, and simple sequence repeat (SSR) molecular markers. Plants were successfully generated only when ??Pera?? sweet orange was used as the embryogenic parent. Fifteen plants were regenerated being 7 tetraploid and 8 diploid. Based on SSR molecular markers analyses all 7 tetraploid regenerated plants revealed to be allotetraploids (somatic hybrids), including 2 from the combination of ??Pera?? sweet orange?+???Fremont?? mandarin, 3 ??Pera?? sweet orange?+???Nules?? mandarin, and 2 ??Pera?? sweet orange?+???Nova?? tangelo, and all the diploid regenerated plants showed the ??Pera?? sweet orange marker profile. Somatic hybrids were inoculated with Alternaria alternata and no disease symptoms were detected 96?h post-inoculation. This hybrid material has the potential to be used as a tetraploid parent in interploid crosses for citrus scion breeding. 相似文献
136.
Consonni SR Rosa RG Nascimento MA Vinagre CM Toledo OM Joazeiro PP 《Histology and histopathology》2012,27(7):885-896
It has been observed that parturition has a significant effect on female skeletal architecture and that age alters musculoskeletal tissues and their functions. We therefore hypothesized that multiparity affects the recovery of the pubic symphysis in senescent mice at postpartum and the morphology of the interpubic tissues. The pubic symphysis of primiparous young, virgin senescent (VS) and multiparous senescent (MS) Swiss mice was examined by light microscopy, transmission electron microscopy, morphometric analysis and immunohistochemistry. The mouse pubic symphysis was remodeled during the first pregnancy: the cellular phenotype and morphology changed to ensure a structurally safe birth canal, followed by recovery of the interpubic articulation after birth. The morphology of the pubic symphysis in the VS group was maintained in a state similar to that observed in virgin young mice. In contrast, MS mice exhibited an interpubic ligament characterized by extended fibrocyte-like cells, an opened interpubic articulation gap, compacted and thin collagen fibrils and scarce galectin-3-positive cells. Thus, we found that the cellular and extracellular characteristics of the pubic symphysis were altered by multiparity in senescent mice. These particular tissue characteristics of the MS group might be associated with an impaired recovery process at postpartum. Thus, a better understanding of the alterations that occur in the birth canal, including the pubic symphysis, due to multiparity in reproductively aged mice may contribute to our comprehension of the biological mechanisms that modify the skeleton and pelvic ligaments and even play a role in the murine model of pelvic organ prolapse. 相似文献
137.
Mendes AA Oliveira PC Vélez AM Giordano RC Giordano Rde L de Castro HF 《International journal of biological macromolecules》2012,50(3):503-511
Five microbial lipase preparations from several sources were immobilized by hydrophobic adsorption on small or large poly-hydroxybutyrate (PHB) beads and the effect of the support particle size on the biocatalyst activity was assessed in the hydrolysis of olive oil, esterification of butyric acid with butanol and transesterification of babassu oil (Orbignya sp.) with ethanol. The catalytic activity of the immobilized lipases in both olive oil hydrolysis and biodiesel synthesis was influenced by the particle size of PHB and lipase source. In the esterification reaction such influence was not observed. Geobacillus thermocatenulatus lipase (BTL2) was considered to be inadequate to catalyze biodiesel synthesis, but displayed high esterification activity. Butyl butyrate synthesis catalyzed by BTL2 immobilized on small PHB beads gave the highest yield (≈90 mmol L(-1)). In biodiesel synthesis, the catalytic activity of the immobilized lipases was significantly increased in comparison to the free lipases. Full conversion of babassu oil into ethyl esters was achieved at 72 h in the presence of Pseudozyma antarctica type B (CALB), Thermomyces lanuginosus lipase (Lipex(?) 100 L) immobilized on either small or large PHB beads and Pseudomonas fluorescens (PFL) immobilized on large PHB beads. The latter preparation presented the highest productivity (40.9 mg of ethyl esters mg(-1) immobilized protein h(-1)). 相似文献
138.
Boyle B Fernandez L Laroche J Kukavica-Ibrulj I Mendes CM Hancock RW Levesque RC 《Journal of bacteriology》2012,194(2):529-530
Clinical "superbug" isolates of Pseudomonas aeruginosa were previously observed to be resistant to several antibiotics, including polymyxin B, and/or to have a distinct, reproducible adaptive polymyxin resistance phenotype, identified by observing "skipped" wells (appearance of extra turbid wells) during broth microdilution testing. Here we report the complete assembled draft genome sequences of three such polymyxin resistant P. aeruginosa strains (9BR, 19BR, and 213BR). 相似文献
139.
Luiz Fernando Mendes Luiz A. S. Vale Aline Paternostro Martins Nair Sumie Yokoya Eliane Marinho-Soriano Pio Colepicolo 《Journal of applied phycology》2012,24(6):1419-1426
In the present study, the daily relative growth rates (DRGR, in percent per day) of the red macroalga Gracilaria domingensis in synthetic seawater was investigated for the combined influence of five factors, i.e., light (L), temperature (T), nitrate (N), phosphate (P), and molybdate (M), using a statistical design method. The ranges of the experimental cultivation conditions were T, 18–26°C; L, 74–162?μmol photons m?2?s?1; N, 40–80?μmol?L?1; P, 8–16?μmol?L?1; and M, 1–5?nmol?L?1. The optimal conditions, which resulted in a maximum growth rate of ≥6.4% d?1 from 7 to 10?days of cultivation, were determined by analysis of variance (ANOVA) multivariate factorial analysis (with a 25 full factorial design) to be L, 74?μmol photons m?2?s?1; T, 26°C; N, 80?μmol?L?1; P, 8?μmol?L?1; and M, 1?nmol?L?1. In additional, these growth rate values are close to the growth rate values in natural medium (von Stosch medium), i.e., 6.5–7.0% d?1. The results analyzed by the ANOVA indicate that the factors N and T are highly significant linear terms, X L, (α?=?0.05). On the other hand, the only significant quadratic term (X Q) was that for L. Statistically significant interactions between two different factors were found between T vs. L and N vs. T. Finally, a two-way (linear/quadratic interaction) model provided a quite reasonable correlation between the experimental and predicted DRGR values (R adjusted 2 ?=?0.9540). 相似文献
140.
Foster NL Paris CB Kool JT Baums IB Stevens JR Sanchez JA Bastidas C Agudelo C Bush P Day O Ferrari R Gonzalez P Gore S Guppy R McCartney MA McCoy C Mendes J Srinivasan A Steiner S Vermeij MJ Weil E Mumby PJ 《Molecular ecology》2012,21(5):1143-1157
Understanding patterns of connectivity among populations of marine organisms is essential for the development of realistic, spatially explicit models of population dynamics. Two approaches, empirical genetic patterns and oceanographic dispersal modelling, have been used to estimate levels of evolutionary connectivity among marine populations but rarely have their potentially complementary insights been combined. Here, a spatially realistic Lagrangian model of larval dispersal and a theoretical genetic model are integrated with the most extensive study of gene flow in a Caribbean marine organism. The 871 genets collected from 26 sites spread over the wider Caribbean subsampled 45.8% of the 1900 potential unique genets in the model. At a coarse scale, significant consensus between modelled estimates of genetic structure and empirical genetic data for populations of the reef-building coral Montastraea annularis is observed. However, modelled and empirical data differ in their estimates of connectivity among northern Mesoamerican reefs indicating that processes other than dispersal may dominate here. Further, the geographic location and porosity of the previously described east-west barrier to gene flow in the Caribbean is refined. A multi-prong approach, integrating genetic data and spatially realistic models of larval dispersal and genetic projection, provides complementary insights into the processes underpinning population connectivity in marine invertebrates on evolutionary timescales. 相似文献