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61.
Giuseppina Mattace Raso Claudio Pirozzi Roberta d'Emmanuele di Villa Bianca Raffaele Simeoli Anna Santoro Adriano Lama Francesca Di Guida Roberto Russo Carmen De Caro Raffaella Sorrentino Antonio Calignano Rosaria Meli 《PloS one》2015,10(5)
Palmitoylethanolamide (PEA), a peroxisome proliferator-activated receptor-α agonist, has been demonstrated to reduce blood pressure and kidney damage secondary to hypertension in spontaneously hypertensive rat (SHR). Currently, no information is available concerning the putative effect of PEA on modulating vascular tone. Here, we investigate the mechanisms underpinning PEA blood pressure lowering effect, exploring the contribution of epoxyeicosatrienoic acids, CYP-dependent arachidonic acid metabolites, as endothelium-derived hyperpolarizing factors (EDHF), and renin angiotensin system (RAS) modulation. To achieve this aim SHR and Wistar-Kyoto rats were treated with PEA (30 mg/kg/day) for five weeks. Functional evaluations on mesenteric bed were performed to analyze EDHF-mediated vasodilation. Moreover, mesenteric bed and carotid were harvested to measure CYP2C23 and CYP2J2, the key isoenzymes in the formation of epoxyeicosatrienoic acids, and the soluble epoxide hydrolase, which is responsible for their degradation in the corresponding diols. Effect of PEA on RAS modulation was investigated by analyzing angiotensin converting enzyme and angiotensin receptor 1 expression. Here, we showed that EDHF-mediated dilation in response to acetylcholine was increased in mesenteric beds of PEA-treated SHR. Western blot analysis revealed that the increase in CYP2C23 and CYP2J2 observed in SHR was significantly attenuated in mesenteric beds of PEA-treated SHR, but unchanged in the carotids. Interestingly, in both vascular tissues, PEA significantly decreased the soluble epoxide hydrolase protein level, accompanied by a reduced serum concentration of its metabolite 14-15 dihydroxyeicosatrienoic acid, implying a reduction in epoxyeicosatrienoic acid hydrolisis. Moreover, PEA treatment down-regulated angiotensin receptor 1 and angiotensin converting enzyme expression, indicating a reduction in angiotensin II-mediated effects. Consistently, a damping of the activation of angiotensin receptor 1 underlying pathways in mesenteric beds was shown in basal conditions in PEA-treated SHR. In conclusion, our data demonstrate the involvement of epoxyeicosatrienoic acids and renin angiotensin system in the blood pressure lowering effect of PEA. 相似文献
62.
Ulrike Pichler Michael Hauser Martin Wolf Maria Livia Bernardi Gabriele Gadermaier Richard Weiss Christof Ebner Hidenori Yokoi Toshiro Takai Alain Didierlaurent Chiara Rafaiani Peter Briza Adriano Mari Heidrun Behrendt Michael Wallner Fátima Ferreira 《PloS one》2015,10(5)
BackgroundPollen released by allergenic members of the botanically unrelated families of Asteraceae and Cupressaceae represent potent elicitors of respiratory allergies in regions where these plants are present. As main allergen sources the Asteraceae species ragweed and mugwort, as well as the Cupressaceae species, cypress, mountain cedar, and Japanese cedar have been identified. The major allergens of all species belong to the pectate lyase enzyme family. Thus, we thought to investigate cross-reactivity pattern as well as sensitization capacities of pectate lyase pollen allergens in cohorts from distinct geographic regions.MethodsThe clinically relevant pectate lyase pollen allergens Amb a 1, Art v 6, Cup a 1, Jun a 1, and Cry j 1 were purified from aqueous pollen extracts, and patients´ sensitization pattern of cohorts from Austria, Canada, Italy, and Japan were determined by IgE ELISA and cross-inhibition experiments. Moreover, we performed microarray experiments and established a mouse model of sensitization.ResultsIn ELISA and ELISA inhibition experiments specific sensitization pattern were discovered for each geographic region, which reflected the natural allergen exposure of the patients. We found significant cross-reactivity within Asteraceae and Cupressaceae pectate lyase pollen allergens, which was however limited between the orders. Animal experiments showed that immunization with Asteraceae allergens mainly induced antibodies reactive within the order, the same was observed for the Cupressaceae allergens. Cross-reactivity between orders was minimal. Moreover, Amb a 1, Art v 6, and Cry j 1 showed in general higher immunogenicity.ConclusionWe could cluster pectate lyase allergens in four categories, Amb a 1, Art v 6, Cup a 1/Jun a 1, and Cry j 1, respectively, at which each category has the potential to sensitize predisposed individuals. The sensitization pattern of different cohorts correlated with pollen exposure, which should be considered for future allergy diagnosis and therapy. 相似文献
63.
Olga Perovic Samantha Iyaloo Ranmini Kularatne Warren Lowman Noma Bosman Jeannette Wadula Sharona Seetharam Adriano Duse Nontombi Mbelle Colleen Bamford Halima Dawood Yesholata Mahabeer Prathna Bhola Shareef Abrahams Ashika Singh-Moodley 《PloS one》2015,10(12)
Introduction
We aimed to obtain an in-depth understanding on recent antimicrobial resistance trends and molecular epidemiology trends of S. aureus bacteraemia (SAB).Methods
Thirteen academic centres in South Africa were included from June 2010 until July 2012. S. aureus susceptibility testing was performed on the MicroScan Walkaway. Real-time PCR using the LightCycler 480 II was done for mecA and nuc. SCCmec and spa-typing were finalized with conventional PCR. We selected one isolate per common spa type per province for multilocus sequence typing (MLST).Results
S. aureus from 2709 patients were included, and 1231 (46%) were resistant to methicillin, with a significant decline over the three-year period (p-value = 0.003). Geographical distribution of MRSA was significantly higher in Gauteng compared to the other provinces (P<0.001). Children <5 years were significantly associated with MRSA with higher rates compared to all other age groups (P = 0.01). The most prevalent SCCmec type was SCCmec type III (531 [41%]) followed by type IV (402 [31%]). Spa-typing discovered 47 different spa-types. The five (87%) most common spa-types were t037, t1257, t045, t064 and t012. Based on MLST, the commonest was ST612 clonal complex (CC8) (n = 7) followed by ST5 (CC5) (n = 4), ST36 (CC30) (n = 4) and ST239 (CC8) (n = 3).Conclusions
MRSA rate is high in South Africa. Majority of the isolates were classified as SCCmec type III (41%) and type IV (31%), which are typically associated with hospital and community- acquired infections, respectively. Overall, this study reveals the presence of a variety of hospital-acquired MRSA clones in South Africa dominance of few clones, spa 037 and 1257. Monitoring trends in resistance and molecular typing is recommended to detect changing epidemiological trends in AMR patterns of SAB. 相似文献64.
65.
Andrea Franzetti Isabella Gandolfi Marco Piscitello Giovanni Porto Adriano Biasiolo Francesca Oltolini Tomaso Marangoni Giuseppina Bestetti 《Biodegradation》2010,21(2):193-201
The effectiveness of biosparging to mitigate N,N diethylaniline in aquifer was evaluated by measuring the time course of decrease in concentration of the aforementioned compound
in aerobic microcosm experiments. The first-order kinetic constant for N,N diethylaniline aerobic biodegradation was estimated from microcosm data (0.037 ± 0.004 d−1), and the value was consistent with the best-fitting value in the transport and reaction model of the aquifer (0.020 d−1). Furthermore, the biodegradability of the compound was evaluated under anaerobic condition in microcosm experiments, which
was supported by field modelling. There was no significant degradation in the anaerobic microcosm experiments, confirming
the recalcitrance of N,N diethyl aniline under the aforementioned aquifer condition. 相似文献
66.
Adriano Caliman Aliny F. Pires Francisco A. Esteves Reinaldo L. Bozelli Vinicius F. Farjalla 《Biodiversity and Conservation》2010,19(3):651-664
The sub-discipline of biodiversity and ecosystem functioning (BEF) has emerged as a central topic in contemporary ecological
research. However, to date no study has evaluated the prominence and publication biases in BEF research. Herein we report
the results of a careful quantitative assessment of BEF research published in five core general ecology journals from 1990
to 2007 to determine the position of BEF research within ecology, identify patterns of research effort within BEF research,
and discuss their probable proximal and historical causes. The relative importance of BEF publications increased exponentially
during the period analyzed and was significantly greater than the average growth of ecological literature, affirming the prominence
of BEF as a current paradigm in ecology. However, BEF research exhibited a strong bias toward experimental studies on terrestrial
plant communities, with significantly lower effort devoted to the functional aspects of biodiversity in aquatic systems, multiple
trophic level systems, and animal or microbial communities. Such trends may be explained by a combination of methodological
adequacy and historic epistemological differences in ecological thinking. We suggest that BEF researchers should direct more
effort toward the study of aquatic systems and animal communities, emphasize long-term and trophically complex experiments,
such as those with multi-trophic microbial communities, employ larger-scale field observational studies and increase the use
of integrative and theoretical studies. Many technical and analytical methodologies that are already employed in ecological
research, such as stable isotopes, paleobiology, remote sensing, and model selection criteria, can facilitate these aims.
Overcoming the above-mentioned shortcomings of current BEF research will greatly improve our ability to predict how biodiversity
loss will affect ecosystem processes and services in natural ecosystems. 相似文献
67.
Ana Carolina Barros de Genaro Rosana Emi Tamagawa Adriano Rodrigues Azzoni Snia Maria Alves Bueno Everson Alves Miranda 《Process Biochemistry》2002,37(12):1413-1420
Aprotinin, a bovine protease inhibitor currently also produced in recombinant bacteria, yeast, and corn, has valuable applications as a human therapeutic and in tissue culture. The objective of this work was to develop the basis of a large-scale aprotinin purification process centered on immobilized metal ion affinity chromatography (IMAC). This technique uses ligands—metal ions—of a lower cost and higher stability than those traditionally used in affinity chromatography. Since aprotinin does not interact with IMAC ligands, collection is from the nonretained fractions (negative chromatography). Stirred-tank batch IMAC adsorption experiments indicated that one-step aprotinin purification could not be successful. Immobilized chymotrypsin chromatography was then used as a prepurification step, yielding a suitable feed for IMAC (with purification factors as high as 476). IMAC column fed with these prepurified materials produced purified aprotinin in the nonretained fractions with purification factors as high as 952. 相似文献
68.
Rasheed Faisal Anjum Naser A. Masood Asim Sofo Adriano Khan Nafees A. 《Journal of Plant Growth Regulation》2022,41(5):1891-1904
Journal of Plant Growth Regulation - The salinization of agriculture soils over the globe has become one of the most devastating stresses and is significantly limiting cultivated land area, and... 相似文献
69.
70.
Nonvisual arrestins are regulated by direct post-translational modifications, such as phosphorylation, ubiquitination, and nitrosylation. However, whether arrestins are regulated by other post-translational modifications remains unknown. Here we show that nonvisual arrestins are modified by small ubiquitin-like modifier 1 (SUMO-1) upon activation of β(2)-adrenergic receptor (β(2)AR). Lysine residues 295 and 400 in arrestin-3 fall within canonical SUMO consensus sites, and mutagenic analysis reveals that Lys-400 represents the main SUMOylation site. Depletion of the SUMO E2 modifying enzyme Ubc9 blocks arrestin-3 SUMOylation and attenuates β(2)AR internalization, suggesting that arrestin SUMOylation mediates G protein-coupled receptor endocytosis. Consistent with this, expression of a SUMO-deficient arrestin mutant failed to promote β(2)AR internalization as compared with wild-type arrestin-3. Our data reveal an unprecedented role for SUMOylation in mediating GPCR endocytosis and provide novel mechanistic insight into arrestin function and regulation. 相似文献