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121.
Markus Egli Simon Hafner Curdin Derungs Judith Ascher-Jenull Federica Camin Giacomo Sartori Gerald Raab Luana Bontempo Mauro Paolini Luca Ziller Tommaso Bardelli Marta Petrillo Samuel Abiven 《Biogeochemistry》2016,131(3):321-338
Only scarce information is available on how organic C is incorporated into the soil during the decay and how (micro) climate influences this process. Therefore, we investigated the effect of exposure and elevation on the organic litter decomposition and C-stabilisation in acidic soils of an Alpine environment. An experiment with artificially 13C labelled Norway spruce needles was carried out at north- and south-exposed sites between 1200 and 2400 m a.s.l. in the Italian Alps using mesocosms. After 1 year, the 13C recoveries of the bulk soil were 18.6% at the north-facing slopes and 31.5% at the south-facing slopes. A density fractionation into a light (LF; ≤1.6 g cm?3) and a heavy fraction (HF; >1.6 g cm?3) of the soil helped to identify how the applied substrate was stabilised. At the northern slope, 10.5% of the substrate was recovered in the LF and 8.1% in the HF and at the south-facing slope 22.8% in the LF and 8.1% in the HF. The overall 13C recovery was higher at the south-facing sites due to restricted water availability. Although the climate is humid in the whole area, soil moisture availability becomes more important at south-facing sites due to higher evapotranspiration. However, at sites >1700 m a.s.l, the situation changed, as the northern slope had higher recovery rates. At such altitudes, temperature effects are more dominant. This highlights the importance of locally strongly varying edaphic factors when investigating the carbon cycle. 相似文献
122.
123.
Elisabetta Caselli Maria D’Accolti Alberta Vandini Luca Lanzoni Maria Teresa Camerada Maddalena Coccagna Alessio Branchini Paola Antonioli Pier Giorgio Balboni Dario Di Luca Sante Mazzacane 《PloS one》2016,11(2)
Background
Contamination of hospital surfaces by clinically-relevant pathogens represents a major concern in healthcare facilities, due to its impact on transmission of healthcare-associated infections (HAIs) and to the growing drug resistance of HAI-associated pathogens. Routinely used chemical disinfectants show limitations in controlling pathogen contamination, due to their inefficacy in preventing recontamination and selection of resistant strains. Recently we observed that an innovative approach, based on a cleanser added with spores of non-pathogenic probiotic Bacilli, was effective in stably counteracting the growth of several pathogens contaminating hospital surfaces.Methods
Here, we wanted to study the impact of the Bacillus-based cleanser on the drug-resistance features of the healthcare pathogens population. In parallel, the ability of cleanser-derived Bacilli to infect hospitalized patients was also investigated.Results
Collected data showed that Bacilli spores can germinate on dry inanimate surfaces, generating the bacterial vegetative forms which counteract the growth of pathogens and effectively substitute for them on treated surfaces. Strikingly, this procedure did not select resistant species, but conversely induced an evident decrease of antibiotic resistance genes in the contaminating microbial population. Also importantly, all the six HAI-positive patients hosted in the treated areas resulted negative for probiotic Bacilli, thus adding evidences to their safety-to-use.Conclusions
These results indicate that this probiotic-based procedure is active not only in controlling surface microbial contamination but also in lowering drug-resistant species, suggesting that it may have relevant clinical and therapeutical implications for the management of HAIs. 相似文献124.
Digestion and absorption of polyunsaturated fatty acids. 总被引:6,自引:0,他引:6
Polyunsaturated fatty acids play an important part in the structure and function of cellular membranes and are precursors of lipid mediators which play a key role in cardiovascular and inflammatory diseases. Dietary sources of essential fatty acids are vegetable oils for either linoleic or alpha-linolenic acids, and sea fish oils for eicosapentaenoic and docosahexaenoic acids. Because of the specificity of the pancreatic lipid hydrolases, triglyceride fatty acid distribution is an essential parameter in the digestibility of fats. The efficiency of the intestinal uptake depends on the hydrolysis and especially on their micellarization. n-3 polyunsaturated fatty acid ethyl ester digestion is recognized to be impaired, but n-3 polyunsaturated fatty acid triglyceride hydrolysis remains a controversial point, and to some authors explains differences observed between vegetable and fish oil absorption. So additional studies are required to investigate this intestinal step. In enterocytes, morphological and biochemical absorption processes involve reesterification of long-chain fatty acids and lipoprotein formation. At this level, specific affinity of I- and L-FABPc (cytosolic fatty acid binding proteins) to polyunsaturated fatty acids requires further investigation. A better understanding of the role of these FABPc might bring to light the esterification step, particularly the integration of polyunsaturated fatty acids into phospholipids. With reference to differences published between fish and vegetable oil absorption, longer-term absorption studies appear essential to some authors. Polyunsaturated fatty acid absorption is thought to be not very dissimilar to that of long-chain mono-unsaturated fatty acid absorption. However, several digestion and absorption specific steps are worth studying with reference to the crucial role of polyunsaturated fatty acids in the organism, and for example adaptation of possible dietary supplements. 相似文献
125.
Lessa JA Ferraz KS Guerra JC de Miranda LF Romeiro CF Souza-Fagundes EM Barbeira PJ Beraldo H 《Biometals》2012,25(3):587-598
Complexes [Au(2)(H(2)Gy3DH)(2)]Cl(2) (1), [Au(H(2)Gy3Me)]Cl(3) (2) and [Au(H(2)Gy3Et)]Cl(3) (3) were obtained with glyoxaldehyde bis(thiosemicarbazone) (H(2)Gy3DH) and its N(3)-methyl (H(2)Gy3Me) and N(3)-ethyl (H(2)Gy3Et) derivatives. The bis(thiosemicarbazones) and their gold(I) and gold(III) complexes exhibited anti-proliferative activity against HL-60, Jurkat (leukemia) and MCF-7 (breast cancer) cells at 10 μmol L(-1). Complex (2) was able to in vitro inhibit thioredoxin reductase (TrxR) activity, which suggests that inhibition of TrxR could be part of its mechanism of action. 相似文献
126.
Priscila L. dos Santos Fabrícia A. de Oliveira Micheli Luize B. Santos Luana Celina S. Cunha Michelle T. B. Lino Michelle F. S. de Oliveira Manuela O. M. Bomfim Angela Maria Silva Tatiana R. de Moura Amélia R. de Jesus Malcolm S. Duthie Steven G. Reed Roque P. de Almeida 《PLoS neglected tropical diseases》2016,10(1)
Background
Visceral leishmaniasis (VL) is a severe disease caused by infection with protozoa of the genus Leishmania. Classic VL is characterized by a systemic infection of phagocytic cells and an intense activation of the inflammatory response. It is unclear why 90% of infected individuals do not develop the disease while a minority develop the classical form. Furthermore, among those that develop disease, a small group progresses to more severe form that is unresponsive to treatment. The presence of inflammatory mediators in serum could theoretically help to control the infection. However, there is also a release of anti-inflammatory mediators that could interfere with the control of parasite multiplication. In this study, we took advantage of the spectrum of outcomes to test the hypothesis that the immune profile of individuals infected with Leishmania (L.) infantum is associated with the development and severity of disease.Methodology/Principal Findings
Sera from patients with confirmed diagnosis of VL were evaluated for the presence of numerous molecules, and levels compared with healthy control and asymptomatic infected individuals.Conclusions/Principal Findings
Although differences were not observed in LPS levels, higher levels of sCD14 were detected in VL patients. Our data suggest that L. infantum may activate the inflammatory response via CD14, stimulating a generalized inflammatory response with production of several cytokines and soluble molecules, including IFN-γ, IL-27, IL-10, IL-6 and sCD14. These molecules were strongly associated with hepatosplenomegaly, neutropenia and thrombocytopenia. We also observed that IL-6 levels greater than 200 pg/ml were strongly associated with death. Together our data reinforce the close relationship of IFN-γ, IL-10, IL-6, TNF-α and IL-27 in the immune dynamics of VL and suggest the direct participation of sCD14 in the activation of the immune response against L. infantum. 相似文献127.
Sigalotti L Fratta E Coral S Cortini E Covre A Nicolay HJ Anzalone L Pezzani L Di Giacomo AM Fonsatti E Colizzi F Altomonte M Calabrò L Maio M 《Journal of cellular physiology》2007,212(2):330-344
In the last three decades huge efforts have been made to characterize genetic defects responsible for cancer development and progression, leading to the comprehensive identification of distinct cellular pathways affected by the alteration of specific genes. Despite the undoubtable role of genetic mechanisms in triggering neoplastic cell transformation, epigenetic modifications (i.e., heritable changes of gene expression that do not derive from alterations of the nucleotide sequence of DNA) are rapidly emerging as frequent alterations that often occur in the early phases of tumorigenesis and that play an important role in tumor development and progression. Epigenetic alterations, such as modifications in DNA methylation patterns and post-translational modifications of histone tails, behave extremely different from genetic modifications, being readily revertable by "epigenetic drugs" such as inhibitors of DNA methyl transferases and inhibitors of histone deacetylases. Since epigenetic alterations in cancer cells affect virtually all cellular pathways that have been associated to tumorigenesis, it is not surprising that epigenetic drugs display pleiotropic activities, being able to concomitantly restore the defective expression of genes involved in cell cycle control, apoptosis, cell signaling, tumor cell invasion and metastasis, angiogenesis and immune recognition. Prompted by this emerging clinical relevance of epigenetic drugs, this review will focus on the large amount of available data, deriving both from in vitro experimentations and in vivo pre-clinical and clinical studies, which clearly indicate epigenetic drugs as effective modifiers of cancer phenotype and as positive regulators of tumor cell biology with a relevant therapeutic potential in cancer patients. 相似文献
128.
Alessandro Franzoi Luana Bontempo Kevin J. Kardynal Federica Camin Paolo Pedrini Keith A. Hobson 《Ibis》2020,162(2):293-306
Understanding spatial linkages between areas used by migratory animals during the annual cycle is fundamental to their conservation. Stable isotope measurements of animal tissues can be a valuable tool in understanding spatial connectivity and migration phenology of migratory wildlife. We inferred natal origins of two migratory passerines, European Pied Flycatcher Ficedula hypoleuca and European Robin Erithacus rubecula, captured during autumn migration in the Italian Alps, by combining feather δ2H (δ2Hf) and ring recovery data. We used a spatially explicit likelihood-based method to assign individuals to a precipitation δ2H surface calibrated to represent feather δ2H, together with the directional probability of origin from ring recoveries. The highest probabilities of origin for most individuals of both species were in central and north-eastern Europe. Seasonal trends in δ2Hf, which described the species’ migratory phenology through the Italian Alps, were correlated with feather δ13C, δ15N and δ34S values, indicating strong spatial discrimination related to continental patterns for these isotopes. We demonstrate how this combined information can define catchment areas and migratory connectivity of birds intercepted in the Alps. We highlight the importance of ringing data in defining directional priors to define Bayesian-based probability surfaces using continental δ2Hf isoscapes, and how such information can be used to inform estimates of migratory connectivity. 相似文献
129.
Urtado MB Gameiro GH Tambeli CH Fischer L Urtado CB de Arruda Veiga MC 《Life sciences》2007,81(23-24):1622-1626
Ethanol withdrawal increases nociception after the injection of formalin into the rat's temporomandibular joint (TMJ). Little is known about the neurological basis for hyperalgesia induced by ethanol withdrawal, but it has been reported that ethanol can potentiate the response of transient receptor potential vanilloid receptor-1 (TRPV1) in superficial tissues. The present study was designed to test the hypothesis that peripheral TRPV1 could be involved on nociceptive behavioral responses induced by the injection of formalin into the TMJ region of rats exposed to chronic ethanol administration and ethanol withdrawal. Behavioral hyperalgesia was verified 12 h after ethanol withdrawal in rats that drank an ethanol solution (6.5%) for 10 days. In another group submitted to the same ethanol regimen, the selective vanilloid receptor antagonist capsazepine (300, 600 or 1200 microg/25 microl) or an equal volume of vehicle were injected into the TMJ regions 30 min before the TMJ formalin test. The local injections of capsazepine reduced the increased nociceptive responses induced by ethanol withdrawal. The effect of capsazepine on rats that did not drink ethanol was not significant. These results indicate that the peripheral TRPV1 can contribute to the hyperalgesia induced by ethanol withdrawal on deep pain conditions. 相似文献
130.
Gabriela Viegas Haute Carolina Luft Géssica Luana Antunes Josiane Silva Silveira Bruno de Souza Basso Mariana Severo da Costa Vitor Giancarlo Schneider Levorse Daniela Benvenutti Kaiber Márcio Vinícius Fagundes Donadio Jordi Gracia-Sancho Jarbas Rodrigues de Oliveira 《Journal of cellular physiology》2020,235(9):6073-6084
Acute lung injury (ALI) is an inflammatory process, and has high incidence and mortality. ALI and the acute respiratory distress syndrome are two common complications worldwide that result in acute lung failure, sepsis, and death. Pro-inflammatory substances, such as cytokines and chemokines, are responsible for activating the body's defense mechanisms and usually mediate inflammatory processes. Therefore, the research of substances that decrease the uncontrolled response of organism is seen as potential for patients with ALI. Octyl gallate (OG) is a phenolic compound with therapeutic actions namely antimicrobial, antiviral, and antifungal. In this study, we evaluated its action on lipopolysaccharide (LPS)-activated alveolar macrophages RAW 264.7 cells and ALI in male mice. Our results demonstrated protective effects of OG in alveolar macrophages activated with LPS and mice with ALI. The OG treatment significantly decreased the inflammatory markers in both studies in vitro and in vivo. The data suggested that OG can act as an anti-inflammatory agent for ALI. 相似文献