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121.
Pedro Romón Z. Wilhelm De Beer Mercedes Fernández Julio Diez Brenda D. Wingfield Michael J. Wingfield 《Antonie van Leeuwenhoek》2014,106(6):1167-1184
Many bark beetles live in a symbiosis with ophiostomatoid fungi but very little is known regarding these fungi in Spain. In this study, we considered the fungi associated with nine bark beetle species and one weevil infesting two native tree species (Pinus sylvestris and Pinus nigra) and one non-native (Pinus radiata) in Cantabria (Northern Spain). This included examination of 239 bark beetles or their galleries. Isolations yielded a total of 110 cultures that included 11 fungal species (five species of Leptographium sensu lato including Leptographium absconditum sp. nov., five species of Ophiostoma sensu lato including Ophiostoma cantabriense sp. nov, and one species of Graphilbum). The most commonly encountered fungal associates of the bark beetles were Grosmannia olivacea, Leptographium procerum, and Ophiostoma canum. The aggressiveness of the collected fungal species was evaluated using inoculations on two-year-old P. radiata seedlings. Leptographium wingfieldii, Leptographium guttulatum, and Ophiostoma ips were the only species capable of causing significant lesions. 相似文献
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123.
Santiago Tofé Povedano Iñaki Argüelles Jiménez Honorato García Fernández Julia Quevedo Juanals Sergio Díaz Medina Guillermo Serra Soler Bartolomé Burguera González Mercedes Codina Marcet Elena Mena Ribas Juan Ramón Urgeles Planella Vicente Pereg Macazaga 《Endocrinología y nutrición》2010,57(2):43-48
IntroductionFine-needle aspiration biopsy (FNAB) is considered the reference diagnostic procedure for thyroid nodules.Materials and methodsRoutine performance of thyroid ultrasound and ultrasound-guided FNAB by endocrinologists allows a more efficient approach in the setting of a high-resolution practice, thus reducing costs and the time elapsed until diagnosis.ResultsWe present our initial results of this procedure 2 years after its introduction, with a total of 286 biopsies performed. After a progressive learning curve over time and according to the endocrinologists’ previous experience, 72.72% samples were considered satisfactory for diagnosis. Greater difficulty was observed in obtaining optimal cytological specimens in smaller nodules. In conclusion, we have successfully incorporated thyroid ultrasound and ultrasound-guided FNAB into routine endocrine practice.ConclusionRoutine performance of thyroid ultrasound in endocrine practice will considerably aid the management of nodular thyroid disease. 相似文献
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125.
Sabina Paglialunga Alexandre Fisette Mercedes Munkonda Ying Gao Denis Richard Katherine Cianflone 《BMC physiology》2010,10(1):4
Background
Acylation stimulating protein (ASP) is an adipogenic hormone that stimulates triglyceride (TG) synthesis and glucose transport in adipocytes. Previous studies have shown that ASP-deficient C3 knockout mice are hyperphagic yet lean, as they display increased oxygen consumption and fatty acid oxidation compared to wildtype mice. In the present study, antibodies against ASP (Anti-ASP) and human recombinant ASP (rASP) were tested in vitro and in vivo. Continuous administration for 4 weeks via osmotic mini-pump of Anti-ASP or rASP was evaluated in wildtype mice on a high-fat diet (HFD) to examine their effects on body weight, food intake and energy expenditure. 相似文献126.
127.
Vasodilator effects of peptides derived from egg white proteins 总被引:1,自引:0,他引:1
The aim of this work was to investigate the effect of several peptides, identified before and after simulated gastrointestinal digestion of an egg white hydrolysate, on the vascular function, in rat aorta. The sequences IVF, RADHPFL and YAEERYPIL (0.1 mM) induced vasodilatation in intact aortic rings, with the maximum percentage of dilation corresponding to RADHPFL (40.5 ± 7.0%). Two of the end products of the gastrointestinal digestion, RADHP and YPI, also showed vasodilator activity with degrees of relaxation higher than 50%. However, all these peptides failed to induce relaxation in endothelium-denuded aortic rings. The relaxation induced by RADHP was concentration-dependent and it was partially blocked by the nitric oxide synthase inhibitor l-NAME (100 μM) and by the B1 bradykinin receptor antagonist Des-HOE 140 (30 nM), thus showing that it was mediated by NO production through the activation of B1 bradykinin receptors. These findings suggest that these peptides could reduce the vascular resistance and could be used as functional food ingredients in the prevention and treatment of hypertension. 相似文献
128.
Lacadena J Alvarez-García E Carreras-Sangrà N Herrero-Galán E Alegre-Cebollada J García-Ortega L Oñaderra M Gavilanes JG Martínez del Pozo A 《FEMS microbiology reviews》2007,31(2):212-237
RNase T1 is the best known representative of a large family of ribonucleolytic proteins secreted by fungi, mostly Aspergillus and Penicillium species. Ribotoxins stand out among them by their cytotoxic character. They exert their toxic action by first entering the cells and then cleaving a single phosphodiester bond located within a universally conserved sequence of the large rRNA gene, known as the sarcin-ricin loop. This cleavage leads to inhibition of protein biosynthesis, followed by cellular death by apoptosis. Although no protein receptor has been found for ribotoxins, they preferentially kill cells showing altered membrane permeability, such as those that are infected with virus or transformed. Many steps of the cytotoxic process have been elucidated at the molecular level by means of a variety of methodological approaches and the construction and purification of different mutant versions of these ribotoxins. Ribotoxins have been used for the construction of immunotoxins, because of their cytotoxicity. Besides this activity, Aspf1, a ribotoxin produced by Aspergillus fumigatus, has been shown to be one of the major allergens involved in allergic aspergillosis-related pathologies. Protein engineering and peptide synthesis have been used in order to understand the basis of these pathogenic mechanisms as well as to produce hypoallergenic proteins with potential diagnostic and immunotherapeutic applications. 相似文献
129.
130.
Outdoor cultivation of microalgae for carotenoid production: current state and perspectives 总被引:1,自引:0,他引:1
Del Campo JA García-González M Guerrero MG 《Applied microbiology and biotechnology》2007,74(6):1163-1174
Microalgae are a major natural source for a vast array of valuable compounds, including a diversity of pigments, for which
these photosynthetic microorganisms represent an almost exclusive biological resource. Yellow, orange, and red carotenoids
have an industrial use in food products and cosmetics as vitamin supplements and health food products and as feed additives
for poultry, livestock, fish, and crustaceans. The growing worldwide market value of carotenoids is projected to reach over
US$1,000 million by the end of the decade. The nutraceutical boom has also integrated carotenoids mainly on the claim of their
proven antioxidant properties. Recently established benefits in human health open new uses for some carotenoids, especially
lutein, an effective agent for the prevention and treatment of a variety of degenerative diseases. Consumers’ demand for natural
products favors development of pigments from biological sources, thus increasing opportunities for microalgae. The biotechnology
of microalgae has gained considerable progress and relevance in recent decades, with carotenoid production representing one
of its most successful domains. In this paper, we review the most relevant features of microalgal biotechnology related to
the production of different carotenoids outdoors, with a main focus on β-carotene from Dunaliella, astaxanthin from Haematococcus, and lutein from chlorophycean strains. We compare the current state of the corresponding production technologies, based
on either open-pond systems or closed photobioreactors. The potential of scientific and technological advances for improvements
in yield and reduction in production costs for carotenoids from microalgae is also discussed. 相似文献