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排序方式: 共有3797条查询结果,搜索用时 15 毫秒
101.
Mario E Arena María S Lisi María R Alberto 《Journal of the science of food and agriculture》2013,93(1):142-148
BACKGROUND: Lactobacillus hilgardii, a wine lactic acid bacterium, is able to use arginine, through the arginine deiminase pathway with the formation of citrulline, a precursor of the carcinogen ethyl carbamate. The influence of different Argentine wine varieties (Merlot, Cabernet Sauvignon and Malbec), on bacterial growth and arginine metabolism was examined. Furthermore, the effect of different components normally present in wines on the enzyme activities of the arginine deiminase system was determined. RESULTS: Malbec wine under all conditions assayed (33, 50 and 100% supplemented wine:basal media) showed higher arginine consumption and citrulline production than the other wines, as well as the highest bacterial growth and survival of Lactobacillus hilgardii X1B. Glucose and L ‐malic inhibited both arginine deiminase enzymes while fructose and citric acid only inhibited arginine deiminase. The red wines assayed in this study had different composition, and this is an explanation for the different behavior of the bacterium. CONCLUSION: The highest citrulline production in Malbec wine could be correlated with its lower concentrations of glucose, fructose, citric and phenolic acid than the other wines. Therefore, a wine with lower concentration of these sugars and acids could be dangerous due to the formation of ethyl carbamate precursors. Copyright © 2012 Society of Chemical Industry 相似文献
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103.
Tiziana Di Chiara Alessandro Del Cuore Mario Daidone Stefania Scaglione Rosario Luca Norrito Maria Grazia Puleo Rosario Scaglione Antonio Pinto Antonino Tuttolomondo 《International journal of molecular sciences》2022,23(5)
There is growing evidence that hypertension is the most important vascular risk factor for the development and progression of cardiovascular and cerebrovascular diseases. The brain is an early target of hypertension-induced organ damage and may manifest as stroke, subclinical cerebrovascular abnormalities and cognitive decline. The pathophysiological mechanisms of these harmful effects remain to be completely clarified. Hypertension is well known to alter the structure and function of cerebral blood vessels not only through its haemodynamics effects but also for its relationships with endothelial dysfunction, oxidative stress and inflammation. In the last several years, new possible mechanisms have been suggested to recognize the molecular basis of these pathological events. Accordingly, this review summarizes the factors involved in hypertension-induced brain complications, such as haemodynamic factors, endothelial dysfunction and oxidative stress, inflammation and intervention of innate immune system, with particular regard to the role of Toll-like receptors that have to be considered dominant components of the innate immune system. The complete definition of their prognostic role in the development and progression of hypertensive brain damage will be of great help in the identification of new markers of vascular damage and the implementation of innovative targeted therapeutic strategies. 相似文献
104.
Elodie Belnoue Alexis Vogelzang Natalie E. Nieuwenhuizen Magdalena A. Krzyzaniak Stephanie Darbre Mario Kreutzfeldt Ingrid Wagner Doron Merkler Paul-Henri Lambert Stefan H. E. Kaufmann Claire-Anne Siegrist Daniel D. Pinschewer 《International journal of molecular sciences》2022,23(5)
Mycobacterium tuberculosis (Mtb) represents a major burden to global health, and refined vaccines are needed. Replication-deficient lymphocytic choriomeningitis virus (rLCMV)-based vaccine vectors against cytomegalovirus have proven safe for human use and elicited robust T cell responses in a large proportion of vaccine recipients. Here, we developed an rLCMV vaccine expressing the Mtb antigens TB10.4 and Ag85B. In mice, rLCMV elicited high frequencies of polyfunctional Mtb-specific CD8 and CD4 T cell responses. CD8 but not CD4 T cells were efficiently boosted upon vector re-vaccination. High-frequency responses were also observed in neonatally vaccinated mice, and co-administration of rLCMV with Expanded Program of Immunization (EPI) vaccines did not result in substantial reciprocal interference. Importantly, rLCMV immunization significantly reduced the lung Mtb burden upon aerosol challenge, resulting in improved lung ventilation. Protection was associated with increased CD8 T cell recruitment but reduced CD4 T cell infiltration upon Mtb challenge. When combining rLCMV with BCG vaccination in a heterologous prime-boost regimen, responses to the rLCMV-encoded Mtb antigens were further augmented, but protection was not significantly different from rLCMV or BCG vaccination alone. This work suggests that rLCMV may show utility for neonatal and/or adult vaccination efforts against pulmonary tuberculosis. 相似文献
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106.
Francesco Borgia Lucia Peterle Paolo Custurone Mario Vaccaro Giovanni Pioggia Sebastiano Gangemi 《International journal of molecular sciences》2022,23(6)
Acne Vulgaris (AV) and Hidradenitis suppurativa (HS) are common chronic inflammatory skin conditions that affect the follicular units that often coexist or are involved in differential diagnoses. Inflammation in both these diseases may result from shared pathways, which may partially explain their frequent coexistence. MicroRNAs (miRNAs) are a class of endogenous, short, non-protein coding, gene-silencing or promoting RNAs that may promote various inflammatory diseases. This narrative review investigates the current knowledge regarding miRNAs and their link to AV and HS. The aim is to examine the role of these molecules in the pathogenesis of AV and HS and to identify possible common miRNAs that could explain the similar characteristics of these two diseases. Five miRNA (miR-155 miR-223-, miR-21, and miRNA-146a) levels were found to be altered in both HS and AV. These miRNAs are related to pathogenetic aspects common to both pathologies, such as the regulation of the innate immune response, regulation of the Th1/Th17 axis, and fibrosis processes that induce scar formation. This review provides a starting point for further studies aimed at investigating the role of miRNAs in AV and HS for their possible use as diagnostic-therapeutic targets. 相似文献
107.
Mario Pansera 《Renewable & Sustainable Energy Reviews》2012,16(9):6694-6704
This paper analyses the current status of rural renewable energy in Bolivia and provides and employs an analysis framework to study the network of stakeholders that determines the adoption, absorption and diffusion of renewable energy technology. The study, moreover, illustrates the impact and implications of traditional indigenous knowledge on the local entrepreneurial ecosystem. 相似文献
108.
Pedrini Matteo Langella Valentina Battaglia Mario Alberto Zaratin Paola 《Scientometrics》2018,114(3):1227-1250
Scientometrics - In recent year, a growing attention is dedicated to the assessment of research’s social impact. While prior research has often dealt with results of research, the last decade... 相似文献
109.
Lithium salts are very important in the production of lithium batteries since they are used as precursors for the fabrication of cathode materials that require very low level of impurities (battery grade). Usually, the lithium extraction process from brine first yields lithium carbonate, which is then used as raw material for the production of other lithium compounds. However, it implies an increase in investment costs, considering more equipment and process stages. To remove the impurities and produce battery‐grade lithium compounds directly from brines, a laboratory‐scale process was developed using the methods of ion exchange and chemical precipitation. Thus, impurity‐free brine ready to be used in an industrial membrane electrolysis process is obtained. Different sequences and operating conditions were investigated for the purification of lithium‐concentrated brines, removing the main impurities of the natural brines: calcium, magnesium, and sulfate. For the characterization of solutions, crystals, and ion‐exchange resins, atomic absorption spectrophotometry, scanning electron microscopy, and X‐ray scattering spectroscopy were used. The results indicate that during the chemical precipitation process, lithium‐concentrated brine reacted with some additives (precipitating agents) at different stages in the batch reactors. Subsequently, the pulp obtained was sedimented and filtered, eliminating or reducing the impurities of the lithium brine. Thus, the most efficient precipitation sequence was evaluated as a function of the removal percentage of the species. The removal efficiencies obtained for Ca+2, Mg+2, and SO4?2 were of 98.93%, 99.93%, and 97.14%, respectively. Thereafter, the use of the ion‐exchange resins reduced the concentration of Ca+2 and Mg+2 to the values below 1 ppm. The combined use of both processes provided promising results that could be applied in the industry. 相似文献
110.
Giovanna Ferrentino Md. Asaduzzaman Matteo Mario Scampicchio 《Critical reviews in food science and nutrition》2018,58(3):386-404
The recovery of high valuable compounds from food waste is becoming a tighten issue in food processing. The large amount of non-edible residues produced by food industries causes pollution, difficulties in the management, and economic loss. The waste produced during the transformation of fruits includes a huge amount of materials such as peels, seeds, and bagasse, whose disposal usually represents a problem. Research over the past 20 years revealed that many food wastes could serve as a source of potentially valuable bioactive compounds, such as antioxidants and vitamins with increasing scientific interest thanks to their beneficial effects on human health. The challenge for the recovery of these compounds is to find the most appropriate and environment friendly extraction technique able to achieve the maximum extraction yield without compromising the stability of the extracted products. Based on this scenario, the aim of the current review is twofold. The first is to give a brief overview of the most important bioactive compounds occurring in fruit wastes. The second is to describe the pro and cons of the most up-to-dated innovative and environment friendly extraction technologies that can be an alternative to the classical solvent extraction procedures for the recovery of valuable compounds from fruit processing. Furthermore, a final section will take into account published findings on the combination of some of these technologies to increase the extracts yields of bioactives. 相似文献