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111.
Marcos Vinicius Meiado Mariana Rojas‐Aréchiga José Alves de Siqueira‐Filho Inara Roberta Leal 《Plant Species Biology》2016,31(2):87-97
Environmental factors are used by plants as spatio‐temporal indicators of favorable conditions for seed germination. Thus, the objective of this study was to determine the effect of light and temperature on seed germination of 30 taxa of Cactaceae occurring in northeastern Brazil and to evaluate whether fluctuations in temperature are capable of altering light sensitivity. The seeds were tested for germination under two light conditions (12 h photoperiod and continuous darkness) and 10 temperature treatments: eight constant temperatures (10, 15, 20, 25, 30, 35, 40 and 45°C) and two alternating temperatures (30/20°C and 35/25°C). The species studied showed two photoblastic responses. All cacti from the Cactoideae subfamily (22 taxa) were classified as positive photoblastic (i.e., no germination in darkness), regardless of the temperature treatment used. Likewise, temperature fluctuation did not alter the seed sensitivity to light. On the other hand, the species of the Opuntioideae (five taxa) and Pereskioideae (three taxa) subfamilies are indifferent to light (i.e., germinated both in the presence and absence of light). The cacti from the areas of Caatinga and Cerrado showed an optimal germination temperature of 30°C, while the species from Atlantic Forest and Restinga areas showed an optimal germination temperature of 25°C. 相似文献
112.
Overcoming challenges on using native seeds for restoration of megadiverse resource‐poor environments: a reply to Madsen et al. 下载免费PDF全文
Roberta L. C. Dayrell André J. Arruda Elise Buisson Fernando A. O. Silveira 《Restoration Ecology》2016,24(6):710-713
Madsen et al. (2016) reviewed several major limiting factors to establishment of seedlings in nonforest ecosystems (NFE), and proposed seed enhancement technologies to overcome these restoration barriers. However, biodiverse nutrient‐poor NFE present additional hurdles that preclude landscape‐scale seed‐based restoration and were not mentioned in their review. Here, we discuss issues related to native seed availability and provenance, and shortfalls in knowledge on seed quality testing and dormancy release that severely hamper restoration of degraded nutrient‐impoverished NFE. We present alternatives for overcoming these challenges and highlight the need for investments to find more practical and cost‐effective options for broad‐scale restoration. 相似文献
113.
Silva Liliane Andrade Lopes Neto Jose Honorio Pereira Cardarelli Haíssa Roberta 《Annals of microbiology》2019,69(4):321-328
Some lactic acid bacteria are capable of producing capsular or extracellular polysaccharides, with desirable technological properties and biological activities. Such polysaccharides produced by lactic acid bacteria are called exopolysaccharides and can be used to alter rheological properties, acting in processes involving viscosity, emulsification, and flocculation, among others. They may also be involved in prebiotic, probiotic, and biological activities, as well as having potential application in the food industry. In this mini-review, the objectives were to present some beneficial properties of exopolysaccharides (EPS) produced by Lactobacillus plantarum that have not been commercially explored. For that, the article focused to summarize revision of current publications within the following topics: (1) rheological properties, (2) prebiotic properties, (3) biological activities, and (4) potential application in the food industry. EPS produced by Lb. plantarum can be used as gelling agent, emulsifier, or stabilizer for food products. The glucan nature of the produced EPS enhances probiotic properties of this LAB species. Lactobacillus plantarum EPS has antioxidant, antibiofilm, and antitumor activities. Finally, there is an improvement in texture of fermented food products where Lb. plantarum is used as starter culture which is related to EPS production in situ. Therefore, EPS produced by Lb. plantarum have important and desirable properties to be explored for several applications, including health and food areas. 相似文献
114.
115.
Roberta De Grandi Pasquale Capaccio Alessandro Bidossi Marta Bottagisio Lorenzo Drago Sara Torretta Lorenzo Pignataro Elena De Vecchi 《Microbes and infection / Institut Pasteur》2019,21(2):109-112
Sialolithiasis represents the most common disorders of salivary glands in middle-aged patients. It has been hypothesized that the retrograde migration of bacteria from the oral cavity to gland ducts may facilitate the formation of stones. Thus, in the present study, a microbiome characterization of salivary calculi was performed to evaluate the abundance and the potential correlations between microorganisms constituting the salivary calculi microbiota. Our data supported the presence of a core microbiota of sialoliths constituted principally by Streptococcus spp., Fusobacterium spp. and Eikenella spp., along with the presence of important pathogens commonly involved in infective sialoadenitis. 相似文献
116.
Roberta Ascrizzi Simonetta Maccioni Gianni Bedini Guido Flamini 《Plant biosystems》2019,153(4):538-543
Two populations of Stachys recta growing in Italy on ultramafic and calcareous soils have been studied for their essential oils. Although the yields were comparable, the composition of the essential oils differed significantly. Plants growing on ultramafic soil produced mainly non-terpene derivatives (55.7%), of which the most abundant ones were 1-octen-3-ol (38.2%) and (E)-3-hexen-1-ol (5.9%); the terpenes α-cadinol (6.1%) and δ-cadinene (5.6%) were also significantly represented. In contrast, the populations living on calcareous soil produced an essential oil dominated by terpenes (93.8%), with germacrene D (18.8%), β-caryophyllene (17.7%), 1,8-cineole (15.9%) and α-pinene (14.2%) among the main components. 相似文献
117.
William T. Barker Courtney E. Chandler Roberta J. Melander Robert K. Ernst Christian Melander 《Bioorganic & medicinal chemistry》2019,27(9):1776-1788
The last three decades have seen a dwindling number of novel antibiotic classes approved for clinical use and a concurrent increase in levels of antibiotic resistance, necessitating alternative methods to combat the rise of multi-drug resistant bacteria. A promising strategy employs antibiotic adjuvants, non-toxic molecules that disarm antibiotic resistance. When co-dosed with antibiotics, these compounds restore antibiotic efficacy in drug-resistant strains. Herein we identify derivatives of tryptamine, a ubiquitous biochemical scaffold containing an indole ring system, capable of disarming colistin resistance in the Gram-negative bacterial pathogens Acinetobacter baumannii, Klebsiella pneumoniae, and Escherichia coli while having no inherent bacterial toxicity. Resistance was overcome in strains carrying endogenous chromosomally-encoded colistin resistance machinery, as well as resistance conferred by the mobile colistin resistance-1 (mcr-1) plasmid-borne gene. These compounds restore a colistin minimum inhibitory concentration (MIC) below the Clinical & Laboratory Sciences Institute (CLSI) breakpoint in all resistant strains. 相似文献
118.
Roberta Piazza Filippo Micheletti Sara Condino Giada Magni Raffaella N. Berchiolli Paolo De Simone Vincenzo Ferrari Mauro Ferrari Roberto Pini Francesca Rossi 《Journal of biophotonics》2019,12(9)
The in situ laser fenestration is an interesting option for the endovascular treatment of short‐necked aneurysms with an intraoperative modification of a standard endograft. According to literature evidence, diode laser emitting in the near‐infrared wavelength (810 nm) can be successfully used to fenestrate the endograft fabric. This paper describes a three‐dimensional navigation system for the accurate targeting of the fenestration site, then reports results of an ex vivo study to assess whether the laser operative conditions, which ensure the fabric fenestration, are harmless for the biological tissue surrounding the endoprosthesis. Two hundred twenty‐five samples of human aorta, including healthy specimens and abdominal aortic aneurysm samples, were irradiated ex vivo using a 810 nm diode laser. Energy and pulse duration were varied. Irradiated tissues were fixed in formaldehyde, sectioned and subjected to histological examination. Only 7.5% of the irradiated samples exhibited a thermal damage, which was always confined to the contact point between the laser fiber tip and the aortic wall. These experiments suggest that the diode laser can be safely used for the proposed surgical application. 相似文献
119.
Asaf Zviran Nofar Mor Yoach Rais Hila Gingold Shani Peles Elad Chomsky Sergey Viukov Jason D. Buenrostro Roberta Scognamiglio Leehee Weinberger Yair S. Manor Vladislav Krupalnik Mirie Zerbib Hadas Hezroni Diego Adhemar Jaitin David Larastiaso Shlomit Gilad Sima Benjamin Jacob H. Hanna 《Cell Stem Cell》2019,24(2):328-341.e9
120.
Megan J. Agajanian Matthew P. Walker Alison D. Axtman Roberta R. Ruela-de-Sousa D. Stephen Serafin Alex D. Rabinowitz David M. Graham Meagan B. Ryan Tigist Tamir Yuko Nakamichi Melissa V. Gammons James M. Bennett Rafael M. Couñago David H. Drewry Jonathan M. Elkins Carina Gileadi Opher Gileadi Paulo H. Godoi Michael B. Major 《Cell reports》2019,26(1):79-93.e8