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941.
Kelly Cristina Araújo Pansard Hélio de Castro Bezerra Gurgel Lorena Candice de Araújo Andrade Maria Emília Yamamoto 《Marine Mammal Science》2011,27(4):673-687
We analyzed the stomach contents of 40 estuarine dolphins, Sotalia guianensis (van Benédén 1864), beached on the coast of Rio Grande do Norte, Brazil, between February 2000 and February 2007. A total of 223 prey items were identified, including 18 species of teleosts and 5 species of cephalopods. The index of relative importance (IRI) showed that Larimus breviceps, Haemulon plumieri, Lutjanus synagris, Trichiurus lepturus, Mugil curema, and Diapterus rhombeus were the six most important species. The IRI showed that L. breviceps was the main prey for both adults and the young. H. plumieri was the most important for the males and T. lepturus for the females. Seven species of teleosts and two of cephalopods were recorded in the diet of estuarine dolphins for the first time in the country. Our results suggest that the estuarine dolphin can be a feeding specialist and that foraging activity occurs mainly in estuarine areas, where the animals can use passive listening to detect prey. 相似文献
942.
Duarte AB Chaves RN Araújo VR Celestino JJ Silva GM Lopes CA Tavares LM Campelo CC de Figueiredo JR 《Zygote (Cambridge, England)》2011,19(3):215-227
The aim of this study was to evaluate the influence of the number of follicles per drop (one or three) and antral follicles on in vitro development of isolated goat preantral follicles. Preantral follicles were isolated through microdissection and distributed individually (control) or in groups of three follicles (treatment) in microdroplets of α-MEM with or without 1000 ng/ml follicle stimulating hormone (FSH) for Experiments 1 and 2, respectively. Experiment 3 was divided into four treatments according to the presence of one or three preantral follicles, associated or not with antral follicles. After culture, oocytes were retrieved from morphologically normal follicles and submitted to in vitro maturation (IVM) and live/dead fluorescent labelling. Results of Experiment 1 (basic medium without FSH) showed that culture of preantral follicles in groups enhances viability, growth and antrum formation after 12 days. However, in the presence of FSH (Experiment 2), only the recovery rate of fully grown oocytes for IVM was significantly affected by grouping of follicles. In Experiment 3, in general, co-culture of preantral follicles with an early antral follicle had a detrimental effect on viability, antrum formation and production of oocytes for IVM. In conclusion, the performance of in vitro culture of goat preantral follicles is affected by the number of follicles per drop, the presence of an antral follicle and FSH. 相似文献
943.
Al-Hourani BJ Sharma SK Mane JY Tuszynski J Baracos V Kniess T Suresh M Pietzsch J Wuest F 《Bioorganic & medicinal chemistry letters》2011,21(6):1823-1826
A series of 1,5-diaryl-substituted tetrazole derivatives was synthesized via conversion of readily available diaryl amides into corresponding imidoylchlorides followed by reaction with sodium azide. All compounds were evaluated by cyclooxygenase (COX) assays in vitro to determine COX-1 and COX-2 inhibitory potency and selectivity. Tetrazoles 3a-e showed IC50 values ranging from 0.42 to 8.1 mM for COX-1 and 2.0 to 200 μM for COX-2. Most potent compound 3c (IC50 (COX-2) = 2.0 μM) was further used in molecular modeling docking studies. 相似文献
944.
This work was aimed to develop water resistant biocide film from renewable resources for applications in food and water technology. Guar gum, a polymeric galactomannan, was intrinsically modified to a new guar gum benzamide. Benzoylation was carried out by benzoyl chloride reaction in water medium and a propyl amine spacer was used to impart a high degree of hydrophobicity. The new guar gum benzamide was resistant to water and soluble in non aqueous solvent like dimethyl sulfoxide. Cast films of thickness 0.162 mm had a breaking point tensile strength of 21.95 Mpa. The water vapor permeability of biomaterial film was 0.28 g mm kPa−1 h−1 m−2 and water contact angle on evaporative surface was 90.35 degree. Qualitative and quantitative biocide activity of film was established against Salmonella enterica, Escherichia coli, Staphylococcus aureus and Bacillus subtilis. The new guar gum benzamide absorbed strongly in UV region. 相似文献
945.
Pushalkar S Mane SP Ji X Li Y Evans C Crasta OR Morse D Meagher R Singh A Saxena D 《FEMS immunology and medical microbiology》2011,61(3):269-277
In the oral cavity, chronic inflammation has been observed at various stages of oral squamous cell carcinomas (OSCC). Such inflammation could result from persistent mucosal or epithelial cell colonization by microorganisms. There is increasing evidence of the involvement of oral bacteria in inflammation, warranting further studies on the association of bacteria with the progression of OSCC. The objective of this study was to evaluate the diversity and relative abundance of bacteria in the saliva of subjects with OSCC. Using 454 parallel DNA sequencing, ~58,000 PCR amplicons that span the V4-V5 hypervariable region of rRNAs from five subjects were sequenced. Members of eight phyla (divisions) of bacteria were detected. The majority of classified sequences belonged to the phyla Firmicutes (45%) and Bacteroidetes (25%). Further, 52 different genera containing approximately 860 (16.51%) known species were identified and 1077 (67%) sequences belonging to various uncultured bacteria or unclassified groups. The species diversity estimates obtained with abundance-based coverage estimators and Chao1 were greater than published analyses of other microbial profiles from the oral cavity. Fifteen unique phylotypes were present in all three OSCC subjects. 相似文献
946.
Gl��ria Pinto S��nia Silva Jo?o Loureiro Armando Costa Maria Celeste Dias Clara Ara��jo Lucinda Neves Concei??o Santos 《Trees - Structure and Function》2011,25(3):383-392
This paper reports the complete process from secondary emblings (SE-derived plants) regeneration to acclimatization of Eucalyptus globulus and describes histocytological changes that occur in leaves from in vitro to ex vitro acclimatization for a 3-month period.
After elongation, plants were transferred to pots with sterilized peat:perlite and acclimatized in a phytotron, with progressive
reduction of RH and increase of light intensity. Histocytological analyses were performed in fixed material using light microscopy
and ultrastructural changes followed by electron microscopy (SEM and TEM). The protocol used allowed the successful acclimatization
of the emblings. Plants looked morphologically normal and FCM screening revealed no ploidy or DNA content abnormalities. Histocytological
analyses showed significant changes along time, mostly in stomata shape and aperture, starch reserves, chloroplast morphology
and mesophyll differentiation. This is the first report concerning emblings acclimatization to ex vitro conditions in Eucalyptus. It was clearly demonstrated that during acclimatization emblings suffered profound changes in leaf morphology in order to
successfully adapt to ex vitro conditions. 相似文献
947.
Wuelton Marcelo Monteiro Ana Paula Margioto Teston Ana Paula Gruendling Daniele dos Reis M?nica Lúcia Gomes Silvana Marques de Araújo Maria Terezinha Bahia Laylah Kelre Costa Magalh?es Jorge Augusto de Oliveira Guerra Henrique Silveira Max Jean de Ornelas Toledo Maria das Gra?as Vale Barbosa 《PLoS neglected tropical diseases》2013,7(2)
Background
In the Brazilian Amazon, clinical and epidemiological frameworks of Chagas disease are very dissimilar in relation to the endemic classical areas of transmission, possibly due to genetic and biological characteristics of the circulating Trypanosoma cruzi stocks. Twenty six T. cruzi stocks from Western Amazon Region attributed to the TcI and TcIV DTUs were comparatively studied in Swiss mice to test the hypothesis that T. cruzi clonal structure has a major impact on its biological and medical properties.Methodology/Principal Findings
Seventeen parameters were assayed in mice infected with 14 T. cruzi strains belonging to DTU TcI and 11 strains typed as TcIV. In comparison with TcI, TcIV stocks promoted a significantly shorter pre-patent period (p<0.001), a longer patent period (p<0.001), higher values of mean daily parasitemia (p = 0.009) and maximum of parasitemia (p = 0.015), earlier days of maximum parasitemia (p<0.001) and mortality (p = 0.018), higher mortality rates in the acute phase (p = 0.047), higher infectivity rates (p = 0.002), higher positivity in the fresh blood examination (p<0.001), higher positivity in the ELISA at the early chronic phase (p = 0.022), and a higher positivity in the ELISA at the late chronic phase (p = 0.003). On the other hand TcI showed higher values of mortality rates in the early chronic phase (p = 0.014), higher frequency of mice with inflammatory process in any organ (p = 0.005), higher frequency of mice with tissue parasitism in any organ (p = 0.027) and a higher susceptibility to benznidazole (p = 0.002) than TcIV. Survival analysis showing the time elapsed from the day of inoculation to the beginning of the patent period was significantly shorter for TcIV strains and the death episodes triggered following the infection with TcI occurred significantly later in relation to TcIV. The notable exceptions come from positivity in the hemocultures and PCR, for which the results were similar.Conclusion/Significance
T. cruzi stocks belonging to TcI and TcIV DTUs from Brazilian Amazon are divergent in terms of biological and medical properties in mice. 相似文献948.
Kazuhito Tsuboi Tatsuya Tai Ryouhei Yamashita Hanif Ali Takashi Watanabe Toru Uyama Yoko Okamoto Keisuke Kitakaze Yasuhiro Takenouchi Shinji Go Iffat Ara Sonia Rahman Hitoshi Houchi Tamotsu Tanaka Yasuo Okamoto Akira Tokumura Junko Matsuda Natsuo Ueda 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2021,1866(9):158972
Bioactive N-acylethanolamines (NAEs) include palmitoylethanolamide, oleoylethanolamide, and anandamide, which exert anti-inflammatory, anorexic, and cannabimimetic actions, respectively. The degradation of NAEs has been attributed to two hydrolases, fatty acid amide hydrolase and NAE acid amidase (NAAA). Acid ceramidase (AC) is a lysosomal enzyme that hydrolyzes ceramide (N-acylsphingosine), which resembles NAAA in structure and function. In the present study, we examined the role of AC in the degradation of NAEs. First, we demonstrated that purified recombinant human AC can hydrolyze various NAEs with lauroylethanolamide (C12:0-NAE) as the most reactive NAE substrate. We then used HEK293 cells metabolically labeled with [14C]ethanolamine, and revealed that overexpressed AC lowered the levels of 14C-labeled NAE. As analyzed with liquid chromatography-tandem mass spectrometry, AC overexpression decreased the amounts of different NAE species. Furthermore, suppression of endogenous AC in LNCaP prostate cells by siRNA increased the levels of various NAEs. Lastly, tissue homogenates from mice genetically lacking saposin D, a presumable activator protein of AC, showed much lower hydrolyzing activity for NAE as well as ceramide than the homogenates from wild-type mice. These results demonstrate the ability of AC to hydrolyze NAEs and suggest its physiological role as a third NAE hydrolase. 相似文献
949.
Rodrigo Cappato de Araújo Helga Tatiana Tucci Rodrigo de Andrade Jaqueline Martins Débora Bevilaqua-Grossi Anamaria Siriani de Oliveira 《Journal of electromyography and kinesiology》2009,19(4):685-694
The purpose of the present study was to evaluate the intra and interday reliability of surface electromyographic amplitude values of the scapular girdle muscles and upper limbs during 3 isometric closed kinetic chain exercises, involving upper limbs with the fixed distal segment extremity on stable base of support and on a Swiss ball (relatively unstable). Twenty healthy adults performed the exercises push-up, bench-press and wall-press with different effort levels (80% and 100% maximal load). Subjects performed three maximal voluntary contractions (MVC) in muscular testing position of each muscle to obtain a reference value for root mean square (RMS) normalization. Individuals were instructed to randomly perform three isometric contraction series, in which each exercise lasted 6 s with a 2-min resting-period between series and exercises. Intra and interday reliabilities were calculated through the intraclass correlation coefficient (ICC 2.1), standard error of the measurement (SEM). Results indicated an excellent intraday reliability of electromyographic amplitude values (ICC ? 0.75). The interday reliability of normalized RMS values ranged between good and excellent (ICC 0.52–0.98). Finally, it is suggested that the reliability of normalized electromyographic amplitude values of the analyzed muscles present better values during exercises on a stable surface. However, load levels used during the exercises do not seem to have any influence on variability levels, possibly because the loads were quite similar. 相似文献
950.
V A Araújo S K Melo A P A Araújo M L M Gomes M A A Carneiro 《Revista brasleira de biologia》2007,67(4):611-617
Several bromeliads species store water and organic substrates, allowing the establishment of phytotelmata and associated fauna on their leaves. In this study, we sampled 70 individuals of Vriesea sp. (Carrière) (Bromeliaceae), in rupestrian fields in the Serra de Ouro Branco-MG, Brazil. The relationships between invertebrate species richness and abundance and size of bromeliads were tested using multiple regression. We found 19 species associated with bromeliads, mainly Diptera larvae. The abundance of the phytotelmate fauna increased principally in relation to the volume of water in the bromeliad reservoir. Phytotelmata richness was affected principally by diameter of the reservoir. There was a significant relationship between the abundance and richness of invertebrates associated with leaves with diameter and height of the plant. Invertebrate richness was better explained by abundance of individuals. These results suggest that the increase of richness was attended by higher numbers of microhabitats and more space for colonization of bigger bromeliads. Additionally, there was more chance of sampling different species in locales with greater abundance of individuals. 相似文献