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991.
Telocytes are the physiological counterpart of inflammatory fibroid polyps and PDGFRA‐mutant GISTs
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Riccardo Ricci Maria Cristina Giustiniani Marco Gessi Paola Lanza Federica Castri Alberto Biondi Roberto Persiani Fabio M. Vecchio Mauro Risio 《Journal of cellular and molecular medicine》2018,22(10):4856-4862
PDGFRA mutations in the gastrointestinal (GI) tract can cause GI stromal tumour (GIST) and inflammatory fibroid polyp (IFP). Hitherto no cell type has been identified as a physiological counterpart of the latter, while interstitial Cajal cells (ICC) are considered the precursor of the former. However, ICC hyperplasia (ICCH), which strongly supports the ICC role in GIST pathogenesis, has been identified in germline KIT‐mutant settings but not in PDGFRA‐mutant ones, challenging the precursor role of ICC for PDGFRA‐driven GISTs. Telocytes are a recently described interstitial cell type, CD34+/PDGFRA+. Formerly considered fibroblasts, they are found in many organs, including the GI tract where they are thought to be involved in neurotransmission. Alongside IFPs and gastric GISTs, GI wall “fibrosis” has been reported in germline PDGFRA‐mutants. Taking the opportunity offered by its presence in a germline PDGFRA‐mutant individual, we demonstrate that this lesion is sustained by hyperplastic telocytes, constituting the PDGFRA‐mutant counterpart of germline KIT mutation‐associated ICCH. Moreover, our findings support a pathogenetic relationship between telocyte hyperplasia and both IFPs and PDGFRA‐mutant GISTs. We propose the term “telocytoma” for defining IFP, as it conveys both the pathogenetic (neoplastic) and histotypic (“telocytary”) essence of this tumour, unlike IFP, which rather evokes an inflammatory‐hyperplastic lesion. 相似文献
992.
Brunella Baratta Riccardo Rizzoli Isabella Galliani Marco Vitale Elena Rizzi Alessandro Matteucci Angela Galanzi Loris Zamai Giovanni Mazzotti 《Histochemistry and cell biology》1996,105(1):61-69
5-Bromodeoxyuridine (BrdU), a synthetic analogue of thymidine, has been utilized in vivo to detect the proliferation which occurs in the liver after two-thirds surgical hepatectomy. Immunocytochemical detection of BrdU incorporation has been carried out at both the morphological and flow cytometrical level, while structural changes of regenerating liver have been investigated, using Mallory-Azan-stained paraffin sections, by means of an image analyser. The results obtained show that in vivo DNA synthesis progression throughout S phase follows a pattern similar to that previously described in vitro in both 3T3 fibroblasts and Friend erythroleukemia cells and also demonstrate a precise correlation between morphological patterns of BrdU incorporating cells and their lobular distribution. Moreover, the activation of at least two proliferation waves can be detected from 18 to 34 h after hepatectomy: the former, starting from adjacent regions of contiguous lobules, apparently induces an irregular increase of lobular dimension; the latter, involving both inner and peripheral lobular domains, seems to be correlated with the appearance of nodule-like structures at the lobule periphery. In view of these results the role of the hepatic acinus and the hypothesis of a streaming of parenchymal cells during liver regeneration have been discussed. 相似文献
993.
Antiserum specific for diamine oxidase (DAO;EC 1.4.3.6) from Lens culinaris cross-reacted with DAO from several other members of the Leguminosae when tested by agar double diffusion. Antibodies purified by affinity chromatography were used to make an immunoadsorbent for the one-step purification of DAO from various species of the Leguminosae. This technique has made it possible to purify in one step the already characterized DAO from pea and lentil, and the unknown diamine oxidase from Cicer arietinum. This enzyme was partially characterized; it showed a pH optimum of 7.5 with putrescine as substrate and followed typical Michaelis-Menten kinetics with a Km of 2.4 × 10?4 M. Copper ligands and carbonyl group-directed reagents inhibited the enzyme. 相似文献
994.
In vivo conversion of [4-14C]sitosterol and [22,23-3H]sitosterol to stigmasterol in barley seedlings
Six-day-old barley seedlings were allowed to take up [4-14C]sitosterol and [22, 23-3H]sitosterol for 2.5 hr and the incorporation into the sterol fractions was determined after 0, 6, 12 and 24 hr. Sitosterol was readily incorporated into every sterol class. The 3H/14C ratio in the free forms dropped when compared with the 3H/14C ratio of the administered sitosterol. In the free sterol, radioactive stigmasterol, showing a 3H/14C ratio half that of the sitosterol 3H/14C ratio, was isolated and its radiochemical purity established by dilution with carrier material and crystallization to constant specific activity. 相似文献
995.
Qin Ning; Olcese Riccardo; Stefani Enrico; Birnbaumer Lutz 《American journal of physiology. Cell physiology》1998,274(5):C1324
Calcium channels are composed of a pore-forming subunit,1, and at least two auxiliarysubunits, - and2-subunits. It is well knownthat -subunits regulate most of the properties of the channel. Thefunction of 2-subunit isless understood. In this study, the effects of the calcium channel2-subunit on the neuronal1E voltage-gated calciumchannel expressed in Xenopus oocyteswas investigated without and with simultaneous coexpression of eitherthe 1b- or the2a-subunit. Most aspects of1E function were affected by2. Thus2 caused a shift in thecurrent-voltage and conductance-voltage curves toward more positivepotentials and accelerated activation, deactivation, and theinstallation of the inactivation process. In addition, the efficiencywith which charge movement is coupled to pore opening assessed bydetermining ratios of limiting conductance to limiting charge movementwas decreased by 2 byfactors that ranged from 1.6 (P < 0.01) for 1E-channels to 3.0 (P < 0.005) for1E1b-channels. These results indicate that2 facilitates the expressionand the maturation of1E-channels and converts thesechannels into molecules responding more rapidly to voltage. 相似文献
996.
997.
998.
Arcangela Iuso Marit Wiersma Hans-Joachim Schüller Ben Pode-Shakked Dina Marek-Yagel Mathias Grigat Thomas Schwarzmayr Riccardo Berutti Bader Alhaddad Bart Kanon Nicola A. Grzeschik Jürgen G. Okun Zeev Perles Yishay Salem Ortal Barel Amir Vardi Marina Rubinshtein Tal Tirosh Yair Anikster 《American journal of human genetics》2018,102(6):1018-1030
999.
Daniele De Luca Paola Cennamo Emanuele Del Guacchio Riccardo Di Novella Paolo Caputo 《Genetica》2018,146(1):29-44
Since its introduction from Central-South America to Italy almost 500 years ago, the common bean (Phaseolus vulgaris L.) was largely cultivated across the peninsula in hundreds of different landraces. However, globalisation and technological modernisation of agricultural practices in the last decades promoted the cultivation of few varieties at the expense of traditional and local agro-ecotypes, which have been confined to local markets or have completely disappeared. The aim of this study was to evaluate the genetic diversity and differentiation in 12 common bean landraces once largely cultivated in the Cilento region (Campania region, southern Italy), and now the object of a recovery program to save them from extinction. The analysis conducted using 13 nuclear microsatellite loci in 140 individuals revealed a high degree of homozygosity within each landrace and a strong genetic differentiation that was reflected in the success in assigning individuals to the source landrace. On the contrary, internal transcribed spacers 1 and 2, analysed in one individual per landrace, were highly similar among common bean landraces but allowed the identification of a cowpea variety (Vigna unguiculata Walp.), a crop largely cultivated in the Old World before the arrival of common bean from Americas. In conclusion, our study highlighted that conservation of landraces is important not only for the cultural and socio-economic value that they have for local communities, but also because the time and conditions in which they have been selected have led to that genetic distinctiveness that is at the basis of many potential agronomical applications and dietary benefits. 相似文献
1000.
Patrizia Ambrogini Maria Cristina Albertini Michele Betti Claudia Galati Davide Lattanzi David Savelli Michael Di Palma Stefania Saccomanno Desirée Bartolini Pierangelo Torquato Gabriele Ruffolo Fabiola Olivieri Francesco Galli Eleonora Palma Andrea Minelli Riccardo Cuppini 《Molecular neurobiology》2018,55(10):7822-7838
Seizure-triggered maladaptive neural plasticity and neuroinflammation occur during the latent period as a key underlying event in epilepsy chronicization. Previously, we showed that α-tocopherol (α-T) reduces hippocampal neuroglial activation and neurodegeneration in the rat model of kainic acid (KA)-induced status epilepticus (SE). These findings allowed us to postulate an antiepileptogenic potential for α-T in hippocampal excitotoxicity, in line with clinical evidence showing that α-T improves seizure control in drug-resistant patients. To explore neurobiological correlates of the α-T antiepileptogenic role, rats were injected with such vitamin during the latent period starting right after KA-induced SE, and the effects on circuitry excitability, neuroinflammation, neuronal death, and microRNA (miRNA) expression were investigated in the hippocampus. Results show that in α-T-treated epileptic rats, (1) the number of population spikes elicited by pyramidal neurons, as well as the latency to the onset of epileptiform-like network activity recover to control levels; (2) neuronal death is almost prevented; (3) down-regulation of claudin, a blood–brain barrier protein, is fully reversed; (4) neuroinflammation processes are quenched (as indicated by the decrease of TNF-α, IL-1β, GFAP, IBA-1, and increase of IL-6); (5) miR-146a, miR-124, and miR-126 expression is coherently modulated in hippocampus and serum by α-T. These findings support the potential of a timely intervention with α-T in clinical management of SE to reduce epileptogenesis, thus preventing chronic epilepsy development. In addition, we suggest that the analysis of miRNA levels in serum could provide clinicians with a tool to evaluate disease evolution and the efficacy of α-T therapy in SE. 相似文献