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21.
Johara Boldrini-França Renata Santos Rodrigues Ludier Kesser Santos-Silva Dayane Lorena Naves de Souza Mário Sérgio Rocha Gomes Camila Takeno Cologna Edwin de Pauw Loïc Quinton Flávio Henrique-Silva Veridiana de Melo Rodrigues Eliane Candiani Arantes 《Applied microbiology and biotechnology》2015,99(23):9971-9986
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Fabiane F. de Almeida Edinaldo N. Santos-Silva Luc Ector Carlos E. Wetzel 《欧洲藻类学杂志》2018,53(2):166-179
A new stalk-forming diatom was observed at high relative abundances on periphytic samples collected in the Rio Negro hydrographic basin (Brazilian Amazon) and is here described using light and scanning electron microscopy. We also present ecological preferences of the new species. Eunotia amazonica sp. nov. co-dominated periphytic samples collected during the rainy seasons of 2013 and 2014 near the city of Manaus (Amazonas, Brazil). The main diagnostic feature of the new species is the stalk-forming growth form (‘Cymbella-like’) illustrated here for the first time in the genus Eunotia Ehrenberg. Previous reports on growth forms in common European databases for this genus included colonial (‘ribbon-like’) but also ‘mobile’, ‘fixed by pads’ or ‘without structures of fixation’. We demonstrated that the three dominant Eunotia species in periphytic samples from the Rio Negro all exhibited distinct ‘growth forms’ or habits: Eunotia amazonica sp. nov. (stalked), Eunotia intricans Metzeltin & Lange-Bertalot (ribbon-like) and Eunotia rabenhorstiana (Grunow) Hustedt (branched-arborescent). The high diversity of species, many of which are unknown to science, as well as the poorly known life-forms and habits of the Eunotiaceae in the region, partially prevent the use of metrics based on life-form to assess ecological changes. Generic assumptions based on robust statistical methods may obscure reality and lead to biased conclusions of diatom community changes in poorly explored regions such as Neotropical freshwater rivers, where the Eunotiaceae are largely dominant, particularly in the Amazon basin. 相似文献
24.
The history of the genus Trichocnemis LeConte, 1851 (Coleoptera, Cerambycidae, Prioninae) is discussed. Its taxonomic status in relation to the genera Ergates Audinet-Serville, 1832 and Callergates Lameere, 1904 is clarified. The synonymy of Macrotoma californica White, 1853, Macrotoma spiculigera White, 1853, and Trichocnemis spiculatus LeConte, 1851 is confirmed. A key to all three genera and their species is provided. 相似文献
25.
Fernandes JC Borges M Nascimento H Bronze-da-Rocha E Ramos OS Pintado ME Malcata FX Santos-Silva A 《International journal of biological macromolecules》2011,49(3):433-438
Two COS mixtures and a low molecular weight chitosan (LMWC) were tested for potential cytotoxicity and genotoxicity upon human lymphocytes. Genotoxicity was evaluated in vitro by cytokinesis-blocked micronucleus and alkaline comet assays, while cytotoxicity was assessed by flow cytometry analysis. Our results suggest that COS do not exhibit any genotoxicity upon human lymphocytes, independently of MW or concentration. However, above 0.07 mg/mL COS induced strong cytotoxic effects. According to the concentration used, such cytotoxicity will induce cell death, essentially by necrosis (>0.10 mg/mL) and/or apoptosis (<0.10 mg/mL). The level of necrosis/apoptosis induced by high COS concentrations, suggests a promising use as apoptosis inducers in specific cancer situations. 相似文献
26.
Jean F. Vettorazzi Rosane A. Ribeiro Junia C. Santos-Silva Patricia C. Borck Thiago M. Batista Tarlliza R. Nardelli Antonio C. Boschero Everardo M. Carneiro 《Amino acids》2014,46(9):2123-2136
Pancreatic β-cells are highly sensitive to suboptimal or excess nutrients, as occurs in protein-malnutrition and obesity. Taurine (Tau) improves insulin secretion in response to nutrients and depolarizing agents. Here, we assessed the expression and function of Cav and KATP channels in islets from malnourished mice fed on a high-fat diet (HFD) and supplemented with Tau. Weaned mice received a normal (C) or a low-protein diet (R) for 6 weeks. Half of each group were fed a HFD for 8 weeks without (CH, RH) or with 5 % Tau since weaning (CHT, RHT). Isolated islets from R mice showed lower insulin release with glucose and depolarizing stimuli. In CH islets, insulin secretion was increased and this was associated with enhanced KATP inhibition and Cav activity. RH islets secreted less insulin at high K+ concentration and showed enhanced KATP activity. Tau supplementation normalized K+-induced secretion and enhanced glucose-induced Ca2+ influx in RHT islets. R islets presented lower Ca2+ influx in response to tolbutamide, and higher protein content and activity of the Kir6.2 subunit of the KATP. Tau increased the protein content of the α1.2 subunit of the Cav channels and the SNARE proteins SNAP-25 and Synt-1 in CHT islets, whereas in RHT, Kir6.2 and Synt-1 proteins were increased. In conclusion, impaired islet function in R islets is related to higher content and activity of the KATP channels. Tau treatment enhanced RHT islet secretory capacity by improving the protein expression and inhibition of the KATP channels and enhancing Synt-1 islet content. 相似文献
27.
Bryce, J. H. and ap Rees, T. 1985. Comparison of the respiratorymetabolism of Plantago lanceolata L. and Plantago major L.J.exp. Bot. 36 15591565. The aim of this work was to discover if the respiratory metabolismof the roots of Plantago lanceolata L. differed from that ofthe roots of Plantago major L. Measurements of oxygen uptakeand dry weight of excised root systems during growth of seedlingsprovided evidence that the two species differed in the amountof respiration needed to support a given increase in dry weight.Excised root systems were given a 6-h pulse in [U-14C]sucrosefollowed by a 16.5-h chase in sucrose. The detailed distributionof 14C amongst the major components of the roots at the endof the pulse and the chase revealed no significant differencebetween the two species. Patterns of 14CO2 production from [1-14C],[2-14C], [3,4-14C], and [6-14C]glucose of excised root systemsfrom plants of three ages were similar for the two species.It is suggested that there is no conclusive evidence for anysignificant inherent difference in the respiratory metabolismof the roots of the two species. Key words: 14C sugar metabolism, respiration, roots, Plantago 相似文献
28.
Antonio Santos-Silva 《法国昆虫学会纪事》2018,54(3):273-291
Hammatoderus wappesi n. sp. and H. garciaorum n. sp. are described from Mexico, Veracruz and Oaxaca and Veracruz, respectively. Hammoderus brasiliensis Breuning, 1943 and Plagiohammus camillus Dillon & Dillon, 1949 are proposed as synonyms of Hammatoderus confusor (Dillon & Dillon, 1941); Plagiohammus rotundipennis Breuning, 1950 is proposed as a synonym of Hammatoderus pollinosus (Bates, 1880). A replacement name, Deliathis neonivea nom. nov., for Deliathis nivea (Breuning, 1943) n. comb., a secondary homonym of D. nivea Bates, 1869, is proposed. Three other new combinations are proposed: Deliathis imperatrix (Thomson, 1868) n. comb.; Monochamus sargi (Bates, 1885) n. comb.; and Monochamus blairi (Breuning, 1936) n. comb. Monochamus sargi and Hammatoderus pollinosus are redescribed. Hammatoderus sticticus (Bates, 1874) is newly recorded from Bolivia, with H. confusor newly recorded from Argentina and Colombia and its known distribution in Brazil expanded to include the state of Sao Paulo. Distribution of Deliathis imperatrix in Mexico is expanded to include the state of Morelos. A key to species of Hammatoderus and a key to species of Taeniotes “amazonum” group are also provided. 相似文献
29.
Four new species of longhorn beetles are described from Brazil: Coleoxestia diamantina n. sp. (Cerambycinae, Cerambycini), from Bahia; Mirador bravoi n. sp. (Cerambycinae, Ectenessini), from Bahia; Compsibidion antonietae n. sp. (Cerambycinae, Neoibidionini), from Goiás, Bahia and São Paulo; and Amphicnaeia quadrifasciata n. sp. (Lamiinae, Apomecynini) from Bahia. Coleoxestia diamantina and Compsibidion antonietae are included in previous keys. 相似文献
30.
Rapid recycling of triose phosphates in oak stem tissue 总被引:10,自引:3,他引:7
S. A. HILL J. S. WATERHOUSE E. M. FIELD V. R. SWITSUR T. AP REES 《Plant, cell & environment》1995,18(8):931-936
We report the carbon-13 and oxygen-18 isotope ratios in cellulose from the early and late wood of pedunculate oak (Quercus robur L.). The δ13 C value of the early wood correlates best with that of the late wood of the previous year. The δ18O value of the early wood correlates best with that of the late wood of the same year. We suggest that a biochemical explanation of these data is that there is a rapid cycle between hexose monophosphates and triose phosphates in oak stem tissue during cellulose synthesis. Evidence in support of this explanation is provided by the intramolecular distribution of 14C in labelled fructose extracted from cores of wood that had been supplied with [1?14C]- and [6-14C]glucose. 相似文献