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971.
Lívia Santos Lima Karina Peres Gramacho José Luis Pires Didier Clement Uilson Vanderlei Lopes Nicolas Carels Abelmon da Silva Gesteira Fernanda Amato Gaiotto Júlio Cézar de Mattos Cascardo Fabienne Micheli 《Tree Genetics & Genomes》2010,6(5):663-676
In this study, we report results of the detection and analysis of SSR markers derived of cacao–Moniliophthora perniciosa expressed sequence tags (ESTs) in relation to cacao resistance to witches’ broom disease (WBD), and we compare the polymorphism
of those ESTs (EST-simple sequence repeat (SSR)) with classical neutral SSR markers. A total of 3,487 ESTs was used in this
investigation. SSRs were identified in 430 sequences: 277 from the resistant genotype TSH 1188 and 153 from the susceptible
one Catongo, totalizing 505 EST-SSRs with three types of motifs: dinucleotides (72.1%), trinucleotides (27.3%), and tetranucleotides
(0.6%). EST-SSRs were classified into 16 main categories; most of the EST-SSRs belonged to “Unknown function” and “No homology”
categories (45.82%). A high frequency of SSRs was found in the 5’UTR and in the ORF (about 27%) and a low frequency was observed
in the 3’UTR (about 8%). Forty-nine EST-SSR primers were designed and evaluated in 21 cacao accessions, 12 revealed polymorphism,
having 47 alleles in total, with an average of 3.92 alleles per locus. On the other hand, the 11 genomic SSR markers revealed
a total of 47 alleles, with an average of 5.22 alleles per locus. The association of EST-SSR with the genomic SSR enhanced
the analysis of genetic distance among the genotypes. Among the 12 polymorphic EST-SSR markers, two were mapped on the F2 Sca 6 × ICS 1 population reference for WBD resistance. 相似文献
972.
The food habits and seed dispersal promoted by five didelphid marsupials, were investigated through fecal analysis in a cerrado reserve located in the central part of the Espinhaço mountain range in Minas Gerais state, southeastern Brazil. The studied species presented a remarkable constancy in their diets and just for C. philander a seasonal change in diet seems to be present with a high consumption of fruits during the wetter season. Arthropods such as hymenopterans, coleopterans and homopterans were the main food resource detected but seeds belonging to pioneer plants were found with high frequencies in samples of all didelphids. Fruits of pioneer plants belonging to the families Melastomataceae (Clidemia urceolata and Miconia holocericea) and Rubiaceae (Psychotria barbiflora and P. capitata) present high germination rates and were among the mostly consumed. In spite of the differences observed in food preferences, all of the didelphids studied must be considered effective seed dispersers of pioneer plants. 相似文献
973.
T. da Silva Rascado B. Watanabe Minto F. da Cruz Landim-Alvarenga 《Theriogenology》2010,74(4):596-601
The objective was to evaluate the parthenogenetic activation of domestic cat oocytes. Cumulus-oocyte complexes matured for 36 h were subjected to three protocols of parthenogenetic activation: Group 1 - ionomycin + cycloheximide; Group 2 - ionomycin + roscovitine; and Group 3 - ionomycin + strontium. As a control, a fourth group of oocytes were cultured in the absence of any activation agent. In all groups, embryos were cultured in SOFaa for 72 h after activation and evaluated for activation rate, cleavage, and embryonic development using Hoechst33342. There were no significant differences among the three treated groups for rates of activated oocytes (70.1 ± 4.3, 75.5 ± 4.7, and 61.9 ± 7.2%, for Treatments 1, 2, and 3 respectively; mean ± SEM), or cleavage (48.1 ± 5.9, 47.4 ± 3.8, and 33.3 ± 6.8%). However, activation and cleavage rates were higher (P < 0.05) than those in the control group (35.5 ± 6.4 and 11.8 ± 4.0%). There were no significant differences among treatment groups for proportion of embryos with 2-10 cells, 10-16 cells, and morulas. In the Control group, the embryo production rate was lower (P < 0.05), although the activation rate was high. The authors concluded that all three treatments effectively induced parthenogenetic activation of domestic cat oocytes. However, to optimize the use of strontium and roscovitine, a dose response and the effect of the presence of Ca++ in the medium requires further study. 相似文献
974.
Zhen Ma Yiqun Cao M. Fátima C. Guedes da Silva João J.R. Fraústo da Silva 《Journal of inorganic biochemistry》2010,104(7):704-711
Reactions between 4′-phenyl-terpyridine (L) and several Zn(II) salts (sulfate, nitrate, chloride or acetate) led to the formation of the complexes [Zn2(μ-O2SO2)2L2(CH3OH)2] (1), [Zn(NO3)L(H2O)]NO3 (2), [Zn(Cl)2L] (3) and [Zn(CH3COO)2L] (4) which were characterized by IR, 1H NMR and fluorescence spectroscopies, elemental analysis and single crystal X-ray diffraction. In the dinuclear molecule of 1 the Zn atom is hexacoordinated, with a N3O3 coordination environment and forms an octagonal ZnOSOZnOSO metallacycle. In the remaining structures, the metal atom is envisaged as possessing highly distorted N3X2 (X = O or Cl) square pyramid coordination geometries. The structure of 3 presents two different packing patterns which lead to distinct π-π stackings. In both structures 2 and 4, strong intermolecular hydrogen bonds were identified. The complexes exhibit promising in vitro tumor-inhibiting activities, which are higher than that of cisplatin, against the following human tumor cell lines: promyelocyticfina leukaemia (HL-60), hepatocellular carcinoma (Bel-7402), gastric carcinoma (BGC-823) and nasopharyngeal carcinoma (KB). 相似文献
975.
Carmen Silvia Martimbianco de Figueiredo Durval Batista Palhares Petr Melnikov Aby Jaine da Cruz Montes Moura Sandra Christo dos Santos 《Biological trace element research》2010,136(1):1-7
Zinc and copper are important trace elements in the nutrition of preterm infants. This study determined and compared the concentrations
of zinc and copper in preterm milk of mothers receiving and not receiving zinc supplementation diets. The effects of maternal
supplementation on the blood levels and anthropometric parameters were evaluated. Thirty-eight mothers and their preterm infants
were enrolled in the study. Eighteen mothers were given a daily supplementation of 50 mg zinc, whereas the other 20 were not.
Zinc and copper levels in milk were determined at 15-day intervals, as were blood zinc levels along with anthropometric parameters.
Zinc and copper contents were determined by atomic absorption spectrophotometry. No significant differences were found between
groups either for zinc values in maternal milk and infant blood or for anthropometric measurements. A pronounced decrease
in copper levels was observed in mothers receiving supplemental zinc. Zinc supplementation given to mothers who were breastfeeding
preterm infants had no significant effect on zinc secretion in milk. 相似文献
976.
Rong An Gabriela da Silva Xavier Francesca Semplici Saharnaz Vakhshouri Jared Rutter Flavio Meggio Guy A. Rutter 《Biochemical and biophysical research communications》2010,399(2):155-161
Pancreatic and duodenal homeobox 1 (PDX1) regulates pancreatic development and mature β-cell function. We demonstrate by mass spectrometry that serine residue at position 269 in the C-terminal domain of PDX1 is phosphorylated in β-cells. Besides we show that the degree of phosphorylation, assessed with a phospho-Ser-269-specific antibody, is decreased by elevated glucose concentrations in both MIN6 β-cells and primary mouse pancreatic islets. Homeodomain interacting protein kinase 2 (HIPK2) phosphorylates PDX1 in vitro; phosphate incorporation substantially decreases in PDX1 S269A mutant. Silencing of HIPK2 led to a 51 ± 0.2% decrease in Ser-269 phosphorylation in MIN6 β-cells. Mutation of Ser-269 to phosphomimetic residue glutamic acid (S269E) or de-phosphomimetic residue alanine (S269A) exerted no effect on PDX1 half-life. Instead, PDX1 S269E mutant displayed abnormal changes in subnuclear localization in response to high glucose. Our results suggest that HIPK2-mediated phosphorylation of PDX1 at Ser-269 might be a regulatory mechanism connecting signals generated by changes in extracellular glucose concentration to downstream effectors via changes in subnuclear localization of PDX1, thereby influencing islet cell differentiation and function. 相似文献
977.
Marco A. Coelho João M. F. Almeida Inês M. Martins A. Jorge da Silva José Paulo Sampaio 《Antonie van Leeuwenhoek》2010,98(3):331-342
Yeasts are common inhabitants of different types of aquatic habitats, including marine and estuarine waters and rivers. Although
numerous studies have surveyed yeast occurrence in these habitats, the identification of autochthonous populations has been
problematic because several yeast species seem to be very versatile and therefore mere presence is not sufficient to establish
an ecological association. In the present study we investigated the dynamics of the yeast community in the Tagus river estuary
(Portugal) by combining a microbiological study involving isolation, quantification, and molecular identification of dominant
yeast populations with the analysis of hydrological and hydrographical data. We set out to test the hypothesis of the multiple
origins of estuarine yeast populations in a transect of the Tagus estuary and we postulate four possible sources: open sea,
terrestrial, gastrointestinal and the estuary itself in the case of populations that have become resident. Candida parapsilosis and Pichia guilliermondii were correlated with Escherichia coli, which indicated an intestinal origin. Other cream-colored yeasts like Debaryomyces hansenii and Candida zeylanoides had similar dynamics, but no association with E. coli and quite distinct ecological preferences. They might represent a group of resident estuarine populations whose primary origin
is diverse and can include marine, terrestrial, and gastrointestinal habitats. Another major yeast population was represented
by Rhodotorula mucilaginosa. The cosmopolitan nature of that species and its moderate association with E. coli point to terrestrial sources as primary habitats. 相似文献
978.
J. M. Maia C. E. Costa de Macedo E. L. Voigt J. B. S. Freitas J. A. G. Silveira 《Biologia Plantarum》2010,54(1):159-163
The aim of this work was to investigate the role of the antioxidant enzymes in salt tolerance comparing the salt-sensitive
(Pérola) and a salt-tolerant (Pitiúba) cultivar of cowpea [Vigna unguiculata (L.) Walp.]. Salt stress (100 mM NaCl for 8 d) reduced the leaf growth rate more in the sensitive cultivar. The salt-induced
decrease in the relative water content, Na+ accumulation and increase in leaf electrolyte leakage was similar in both cultivars. Salt stress induced a higher increase
in the activities of superoxide dismutase (SOD), ascorbate peroxidase (APX) and phenol peroxidase (POX) in the tolerant cultivar
than in sensitive one. 相似文献
979.
Background
Xylella fastidiosa, a Gram-negative fastidious bacterium, grows in the xylem of several plants causing diseases such as citrus variegated chlorosis. As the xylem sap contains low concentrations of amino acids and other compounds, X. fastidiosa needs to cope with nitrogen limitation in its natural habitat. 相似文献980.
David Navarro Marie Couturier Gabriela Ghizzi Damasceno da Silva Jean-Guy Berrin Xavier Rouau Marcel Asther Christophe Bignon 《Microbial cell factories》2010,9(1):58