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111.
Résumé Les auteurs décrivent une nouvelle méthode de coloration dans le bloc de tissu avec différents sels métalliques (alun de fer, tétroxyde d'osmium, acétate d'uranyl et chromeosmium) et l'hématoxyline. Cette technique est utilisée sur des tissus qui sont ensuite inclus en Araldit et permet d'obtenir des coupes semi-fines déjà colorées. Les auteurs ont cherché à préciser la spécificité de fixation du fer dans le tissu au moyen de méthodes d'extraction et de blocage. D'après leurs observations, le fer se fixerait aux groupes tissulaires chargés négativement. La nature des liaisons semble être de type électrostatique et complexe. Les liaisons complexes semblent prédominer au niveau des structures contenant des acides nucléiques.
Histochemistry of block staining with metals for semifine sections
Summary The authors describe a new method of block staining for semifine sections with various metal salts (ferriammonium-sulphate, osmium tetroxyde, uranyl acetate, chromeosmium) and hematoxylin. They investigated the specificity of iron-alaun-hematoxylin with several extractions and blocking methods. According to their observations the dissociated iron is bounded to the negatively charged tissular groups. The nature of binding is thought to be electrostatic and coordinativ (complex). The last one is probably predominant in nucleic acids containing structures. This method seems to be encouraging for electron-histochemical investigations.相似文献
112.
Mariarosaria Bucci Anna Cantalupo Valentina Vellecco Elisabetta Panza Maria Chiara Monti Angela Zampella Angela Ianaro Giuseppe Cirino 《PloS one》2013,8(3)
Here we have characterized perthamide C, a cyclopeptide from a Solomon Lithistid sponge Theonella swinhoei, which displays an anti-inflammatory/immunomodulatory activity. The study has been performed using the carragenan-induced mouse paw edema that displays an early (0–6 h) and a late phase (24–96 h). Perthamide C significantly inhibits neutrophils infiltration in tissue both in the early and late phases. This effect was coupled to a reduced expression of the endothelial nitric oxide synthase (eNOS) in the early phase while cyclooxygenase-1 and 2 (COX-1, COX-2), and inducible NOS (iNOS) expression were unaffected. In the late phase perthamide C reduced expression of both NOS isoforms without affecting COXs expression. This peculiar selectivity toward the two enzymes deputed to produce NO lead us to investigate on a possible action of perthamide C on lymphocytes infiltration and activation. We found that perthamide C inhibited the proliferation of peripheral lymphocytes, and that this effect was secondary to its metabolic activation in vivo. Indeed, in vitro perthamide C did not inhibit proliferation as opposite to its metabolite perthamide H.In conclusion, perthamide C selectively interferes with NO generation triggered by either eNOS or iNOS without affecting either COX-1 or COX-2. This in turn leads to modulation of the inflammatory response through a reduction of vascular permeability, neutrophil infiltration as well as lymphocyte proliferation. 相似文献
113.
Antonio Mauceri Laura Bassolino Antonio Lupini Franz Badeck Fulvia Rizza Massimo Schiavi Laura Toppino Maria Rosa Abenavoli Giuseppe L. Rotino Francesco Sunseri 《植物学报(英文版)》2020,62(4):487-508
Eggplant (Solanum melongena L.) yield is highly sensitive to N fertilization, the excessive use of which is responsible for environmental and human health damage. Lowering N input together with the selection of improved Nitrogen‐Use‐Efficiency (NUE) genotypes, more able to uptake, utilize, and remobilize N available in soils, can be challenging to maintain high crop yields in a sustainable agriculture. The aim of this study was to explore the natural variation among eggplant accessions from different origins, in response to Low (LN) and High (HN) Nitrate (NO3‐) supply, to identify NUE‐contrasting genotypes and their NUE‐related traits, in hydroponic and greenhouse pot experiments. Two eggplants, AM222 and AM22, were identified as N‐use efficient and inefficient, respectively, in hydroponic, and these results were confirmed in a pot experiment, when crop yield was also evaluated. Overall, our results indicated the key role of N‐utilization component (NUtE) to confer high NUE. The remobilization of N from leaves to fruits may be a strategy to enhance NUtE, suggesting glutamate synthase as a key enzyme. Further, omics technologies will be used for focusing on C‐N metabolism interacting networks. The availability of RILs from two other selected NUE‐contrasting genotypes will allow us to detect major genes/quantitative trait loci related to NUE. 相似文献
114.
Felicia Carotenuto Laura Teodori Anna Maria Maccari Luciano Delbono Giuseppe Orlando Paolo Di Nardo 《Journal of cellular and molecular medicine》2020,24(5):2704-2716
Regenerative therapies including stem cell treatments hold promise to allow curing patients affected by severe cardiac muscle diseases. However, the clinical efficacy of stem cell therapy remains elusive, so far. The two key roadblocks that still need to be overcome are the poor cell engraftment into the injured myocardium and the limited knowledge of the ideal mixture of bioactive factors to be locally delivered for restoring heart function. Thus, therapeutic strategies for cardiac repair are directed to increase the retention and functional integration of transplanted cells in the damaged myocardium or to enhance the endogenous repair mechanisms through cell-free therapies. In this context, biomaterial-based technologies and tissue engineering approaches have the potential to dramatically impact cardiac translational medicine. This review intends to offer some consideration on the cell-based and cell-free cardiac therapies, their limitations and the possible future developments. 相似文献
115.
Jacopo Burrello Sara Bolis Carolina Balbi Alessio Burrello Elena Provasi Elena Caporali Lorenzo Grazioli Gauthier Andrea Peirone Fabrizio D'Ascenzo Silvia Monticone Lucio Barile Giuseppe Vassalli 《Journal of cellular and molecular medicine》2020,24(17):9945-9957
The current standard biomarker for myocardial infarction (MI) is high‐sensitive troponin. Although powerful in clinical setting, search for new markers is warranted as early diagnosis of MI is associated with improved outcomes. Extracellular vesicles (EVs) attracted considerable interest as new blood biomarkers. A training cohort used for diagnostic modelling included 30 patients with STEMI, 38 with stable angina (SA) and 30 matched‐controls. Extracellular vesicle concentration was assessed by nanoparticle tracking analysis. Extracellular vesicle surface‐epitopes were measured by flow cytometry. Diagnostic models were developed using machine learning algorithms and validated on an independent cohort of 80 patients. Serum EV concentration from STEMI patients was increased as compared to controls and SA. EV levels of CD62P, CD42a, CD41b, CD31 and CD40 increased in STEMI, and to a lesser extent in SA patients. An aggregate marker including EV concentration and CD62P/CD42a levels achieved non‐inferiority to troponin, discriminating STEMI from controls (AUC = 0.969). A random forest model based on EV biomarkers discriminated the two groups with 100% accuracy. EV markers and RF model confirmed high diagnostic performance at validation. In conclusion, patients with acute MI or SA exhibit characteristic EV biomarker profiles. EV biomarkers hold great potential as early markers for the management of patients with MI. 相似文献
116.
Giovanna Carr Paolo Nicoli Marcello Francesco Lingua Beatrice Maffeo Antonio Cartell Paola Circosta Mara Brancaccio Guido Parvis Valentina Gaidano Angelo Guerrasio Giuseppe Saglio Riccardo Taulli Alessandro Morotti 《Journal of cellular and molecular medicine》2020,24(2):1650-1657
The development of drugs able to target BTK, PI3k‐delta and BCL2 has dramatically improved chronic lymphocytic leukaemia (CLL) therapies. However, drug resistance to these therapies has already been reported due to non‐recurrent changes in oncogenic pathways and genes expression signatures. In this study, we investigated the cooperative role of the BCL2 inhibitor venetoclax and the BRD4 inhibitor JQ1. In particular, we found that JQ1 shows additional activity with venetoclax, in CLL cell lines and in ex vivo isolated primary CD19+ lymphocytes, arguing in favour of combination strategies. Lastly, JQ1 is also effective in venetoclax‐resistant CLL cell lines. Together, our findings indicated that the BET inhibitor JQ1 could be a promising therapy in CLL, both as first‐line therapy in combination with venetoclax and as second‐line therapy, after the emergence of venetoclax‐resistant clones. 相似文献
117.
Lamiaceae is one of the largest families of flowering plants comprising about 250 genera and over 7,000 species. Most of the plants of this family are aromatic and therefore important source of essential oils. Lamiaceae are widely used as culinary herbs and reported as medicinal plants in several folk traditions. In the Mediterranean area oregano, sage, rosemary, thyme and lavender stand out for geographical diffusion and variety of uses. The aim of this review is to provide recent data dealing with the phytochemical and pharmacological studies, and the more recent applications of the essential oils and the non‐volatile phytocomplexes. This literature survey suggests how the deeper understanding of biomolecular processes in the health and food sectors as per as pest control bioremediation of cultural heritage, or interaction with human microbiome, fields, leads to the rediscovery and new potential applications of well‐known plants. 相似文献
118.
Tonia Luca Edoardo Napoli Giovanna Privitera Nicol Musso Giuseppe Ruberto Sergio Castorina 《化学与生物多样性》2020,17(8)
Colon cancer is one of the most common human malignancies, and chemotherapy cannot yet prevent recurrence in all patients. Essential oils are phytocomplexes with antiproliferative properties. In this study, we elucidated the antiproliferative properties and the effect on cell cycle progression of Sicilian Salvia officinalis essential oil and its three main compounds, α‐thujone, 1,8‐cineole (eucalyptol) and camphor, on three human colon cancer cell lines. The essential oil was obtained by hydrodistillation and analyzed by gas chromatography. Cell proliferation was evaluated by MTT assay, and the cell cycle distribution was determined by flow cytometry. Thirty‐four compounds were identified in the tested essential oil. Growth inhibition was observed after 72 h, with an impact on cell cycle progression and no effect on the viability of normal colonic epithelial cells. The study shows that S. officinalis essential oil and its three main components have an in vitro antiproliferative effect on colon cancer cells. 相似文献
119.
Michael J. D'Occhio Giuseppe Campanile Luigi Zicarelli Jos A. Visintin Pietro S. Baruselli 《Molecular reproduction and development》2020,87(2):206-222
Cell–cell adhesion molecules have critically important roles in the early events of reproduction including gamete transport, sperm–oocyte interaction, embryonic development, and implantation. Major adhesion molecules involved in reproduction include cadherins, integrins, and disintegrin and metalloprotease domain‐containing (ADAM) proteins. ADAMs on the surface of sperm adhere to integrins on the oocyte in the initial stages of sperm–oocyte interaction and fusion. Cadherins act in early embryos to organize the inner cell mass and trophectoderm. The trophoblast and uterine endometrial epithelium variously express cadherins, integrins, trophinin, and selectin, which achieve apposition and attachment between the elongating conceptus and uterine epithelium before implantation. An overview of the major cell–cell adhesion molecules is presented and this is followed by examples of how adhesion molecules help shape early reproductive events. The argument is made that a deeper understanding of adhesion molecules and reproduction will inform new strategies that improve embryo survival and increase the efficiency of natural mating and assisted breeding in cattle. 相似文献
120.
Federico Romiti Adele Magliano Valeria Antognetti Giuseppe Manna Antonella Cersini Maria Teresa Scicluna Claudio De Liberato 《Journal of vector ecology》2020,45(1):25-31
Babesia caballi and Theileria equi are widely recognized as causative agents of equine pirolasmosis (EP), an acute, sub‐acute, and chronic disease of equines, with relevant economic impact on horse trade worldwide. Although several studies on EP prevalence from central Italy have been published, data on ticks responsible for its transmission are still lacking. In this study, we identified a potential competent vector, investigating main features of its ecology together with EP infection rates. A two‐year sampling of questing ticks was carried out for the first time in Italy in an area known for high EP prevalence in horse sera, detecting the association between Rhipicephalus bursa and causative agents of EP. Most of the positive pools harbored a single infection (91.1%); mixed infections were also detected (8.9%). The infection rate for T. equi slightly decreased among years; B. caballi showed a lower, but increasing, infection rate. Tick phenology, climate variables, and peaks of EP prevalence indicated late May and second half of June as periods with the highest risk of new infections, especially during warm and dry days. 相似文献