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排序方式: 共有461条查询结果,搜索用时 15 毫秒
61.
Sara Righi Luca Forti Roberto Simonini Valentina Ferrari Daniela Prevedelli Adele Mucci 《Marine drugs》2022,20(9)
Increasing evidence in the field of bioprospection fosters the necessity of studying poorly investigated poisonous marine invertebrates to expand knowledge on animal venom biology. Among marine annelids, amphinomid fireworms are notorious for their bearded trunk equipped with a powerful stinging capacity. Here, a methodological workflow based on analytical chemistry techniques (compound isolation followed by mass spectrometry and spectroscopy analyses) was applied to gain new insights, leading to the identification and structural elucidation of an array of natural products from Mediterranean specimens of Hermodice carunculata. Eight betaine-derived unprecedented compounds, named “carunculines”, were detected, bearing two terminal ammonium groups tri-and disubstituted at the Cα (A, B) and a series of different alkyl chains (I–VIII). The mixture of chemicals was found in all the body parts of H. carunculata, supporting a mechanism of action triggered by their vehiculation inside the dorsal chaetae, and subsequent injection when chaetae break off on contact. Preliminary investigations to understand adaptive features were also performed, showing a trend in carunculine abundance that fits into the evolutionary history of these worms. These findings shed light on the chemical ecology of amphinomids, giving reasons for the success of H. carunculata in benthic environments and providing promising novel metabolites for biotechnological implications. 相似文献
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63.
Erica Ilaria Ferraris Matteo Olimpo Davide Giacobino Luca Manassero Selina Iussich Elena Lardone Mariateresa Camerino Paolo Buracco Emanuela Maria Morello 《Veterinary and comparative oncology》2023,21(2):208-220
It is known that the regional lymph node (RLN) may not correspond to the sentinel lymph node (SLN) (the first lymph node draining the tumour), and many diagnostic techniques have recently been aimed at its detection. Although lymphoscintigraphy is the gold standard in both human and veterinary medicine for SLN mapping, it is relatively unavailable in veterinary medicine due to costs and difficult management of the radiotracer. This prospective study evaluated, as a first aim, the feasibility and sensitivity of the computed tomography lymphography (CTL) in detecting the SLN in 62 mast cell tumours (MCTs). The second aim was to evaluate the accuracy of the CTL in identifying the most representative lymph node of the patient's lymphatic status; the histological status of the SNL was compared with that of the RLN, to see in how many cases the patient's stage would have changed according to the RLN. When the RLN turned out to be also the SLN it was decided to excise, as a control LN, the one localised in the neighbourhood of the MCT (neighbouring lymph node; NLN). The detection rate was 90%, with failure of SLN identification in six cases. In 18 (32%) of 56 MCTs with a diagnostic CTL, the SLN did not correspond to the RLN. Forty-five MCTs were surgically removed, together with their corresponding SLN and RLN/NLN. Since the clinical stage of the patient would have changed in only 7% of cases, CTL is a reliable method of detecting the SLN and, for staging purposes, there is no need to remove other LNs. 相似文献
64.
Chiaradia E Gaiti A Scaringi L Cornacchione P Marconi P Avellini L 《Veterinary research》2002,33(6):661-668
To better define the species-specific antioxidant systems and to ascertain the influence of the intracellular redox status on the immune system of different animal species, we determined lymphocyte glutathione peroxidase (GSHPx) activity, plasmatic glutathione levels (GSH) and the effect of H2O2 on the responsiveness of lymphocytes to proliferative stimuli. Among the three species considered, sheep presented the lowest plasmatic GSH and the highest lymphocyte GSHPx activity. On the contrary, dogs showed an inverted pattern (high GSH - low GSHPx). Horses displayed intermediate values for both parameters analysed. The effect of H2O2 on the proliferative capacity of lymphocytes was the same for all three species; the 200 microM dose in particular was strongly inhibiting. Each species, however, showed different rates of inhibition: sheep exhibited the highest sensitivity to the antiproliferative effect of H2O2. Our results confirmed that high H2O2 concentrations (200 microM) are noxious for the cellular functions of all animals; however this effect is mediated by a rigorously species-specific relationship between the intracellular reactive oxygen species (ROS) and the molecular systems involved in cell proliferation. 相似文献
65.
José M. Alvarez-Suarez Francesca Giampieri Massimiliano Gasparrini Luca Mazzoni Tamara Y. Forbes-Hernández Sadia Afrin Maurizio Battino 《Plant foods for human nutrition (Dordrecht, Netherlands)》2018,73(1):18-24
We analyzed guava fruits (Psidium guajava L. cv. Red Suprema) from Cuba to determine their chemical composition, total antioxidant capacity, as well as their protective effect against oxidative damage using an in vitro model of human dermal fibroblasts. The guava fruit is a natural source of bioactive compounds, such as polyphenols, vitamin C, folates and beta carotenes with proven health benefits. Human dermal fibroblasts were pre-incubated with different concentrations of guava crude extract and then subjected to oxidative stress using the AAPH stressor. The number of apoptotic and dead cells, as well as the markers of oxidative damage such as lipid and protein oxidation significantly decreased when cells were pre-incubated with guava crude extract and then exposed to the stressor. The activity of antioxidant enzymes also improved when cells were pre-incubated with guava crude extract in comparison to cells subjected to stress without prior pre-incubation with the guava extract. The results obtained in this study highlight the health benefits of guava regarding oxidative stress, proving it to be an important source of bioactive compounds associated with important biological properties. 相似文献
66.
67.
Ferasin L 《Journal of Feline Medicine and Surgery》2009,11(2):149-152
A 9-year-old male neutered Devon Rex cat was presented for continued investigations following a 7-year history of recurrent syncope. Previous diagnostic tests, including 24h (Holter) electrocardiographic monitoring, had failed to identify the aetiology of such episodes, and former empirical treatment with atenolol had not provided satisfactory control of the clinical signs. A conclusive diagnosis was eventually achieved using an implantable loop recorder (Reveal), which identified paroxysmal supraventricular tachycardia (SVT) associated with a syncopal episode. Treatment with oral sotalol was instituted and, 18 months after initiation of anti-arrhythmic therapy, no further syncopal episodes have been observed by the cat's owners. 相似文献
68.
L. Senni C. Casieri A. Bovino M. C. Gaetani F. De Luca 《Wood Science and Technology》2009,43(1-2):167-180
It is proposed the use of a mobile device based on a NMR single-sided sensor for in situ non-invasive determination of the moisture content (MC) of wood items, especially items of Cultural Heritage interest. The MC is obtained through the moisture volume fraction, which is an appropriate quantity for the sensor and corresponds to the fraction of its measurements sensitive volume occupied by water. The device has been used here to track changes in MC of wood specimens caused by changes over time of the environmental relative humidity. The kinetics of water adsorption has been related to results obtained with the gravimetric method. Measurements on an old painting, the Pietà (1516–1517), oil on a poplar wood panel by Sebastiano del Piombo (1485 Venice, 1547 Rome), Civic Museum, Viterbo, Italy, have shown, conclusively, the good sensitivity of the sensor and its capability to behave as a non-invasive and in situ utilizable device. Results of in situ painting measurements show that the NMR sensor can track moisture fluctuations that are outside the sensitivity range and precision of electro-hygrometric approach. 相似文献
69.
70.
Monica Puccini Lorenzo Guazzelli Andrea Luca Tasca Andrea Mezzetta Christian Silvio Pomelli 《Water, air, and soil pollution》2018,229(7):239
Thallium is an emerging contaminant, which can be retained in scale encrustation within the pipeline and then released to drinking water. It is included in the Priority Pollutant List of the U.S. EPA. In this study, a sample from the water pipeline of Pietrasanta (Italy), affected by the contamination of thallium, is characterized by SEM-EDS, TGA, and FT-IR. Fluorescence spectroscopy is then proposed as the optimal technique for the detection of the contaminant. The functionality of a previously reported fluorescent calix[4]arene-based chemosensor is verified first on a standard solution of thallium nitrate and then on the sample under investigation. The quenching of the fluorescence of the sensor during the complexation of thallium is confirmed, identifying an ON-OFF sensor with high sensitivity, able to detect concentrations as low as 10?6 M and with high potential of development for the in situ and fast monitoring of the pollutant in the water network. 相似文献