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871.
Fabricia de Souza Predes Maria Aparecida da Silva Diamante Mary Ann Foglio Camila Almeida Camargo Hiroshi Aoyama Silvio Cesar Miranda Bread Cruz Maria Cristina Cintra Gomes Marcondes Heidi Dolder 《Biological trace element research》2014,160(2):250-257
This study was performed to determine the effects of Arctium lappa (Al) to protect against cadmium damage in the rat liver. Male rats received a single i.p. dose of CdCl2 (1.2 mg/kg body weight (BW)) with or without Al extract administered daily by gavage (300 mg/kg BW) for 7 or 56 days. After 7 days, Al caused plasma transaminase activity to diminish in groups Al (glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT)) and CdAl (GPT). After 56 days, GOT and GPT plasma activities were reduced in the Cd group. No alteration in plasma levels of creatinine, total bilirubin, and total protein were observed. GOT liver activity increased in the Cd group. No alteration was observed in superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), and malondialdehyde (MDA) dosage. In the Cd group, hepatocyte proportion decreased and sinusoid capillary proportion increased. In the Al and CdAl groups, the nuclear proportion increased and the cytoplasmic proportion decreased. The hepatocyte nucleus density reduced in Cd and increased in the Al group. After 56 days, there was no alteration in the Cd group. In Al and CdAl groups, the nuclear proportion increased without cytoplasmic proportion variation, but the sinusoid capillary proportion was reduced. The hepatocyte nucleus density decreased in the Cd group and increased in the Al and CdAl groups. In conclusion, the liver function indicators showed that A. lappa protected the liver against cadmium toxicity damage. 相似文献
872.
Luiz Eduardo Rizzo de Souza Michele Dietrich Moura Costa Evandro Santos Bilek Marilene Hohmuth Lopes Vilma Regina Martins Andreas W. Püschel Adriana F. Mercadante Lia Sumie Nakao Silvio Marques Zanata 《Experimental cell research》2014
Rnd proteins comprise a branch of the Rho family of small GTP-binding proteins, which have been implicated in rearrangements of the actin cytoskeleton and microtubule dynamics. Particularly in the nervous system, Rnd family proteins regulate neurite formation, dendrite development and axonal branching. A secreted form of the co-chaperone Stress-Inducible Protein 1 (STI1) has been described as a prion protein partner that is involved in several processes of the nervous system, such as neurite outgrowth, neuroprotection, astrocyte development, and the self-renewal of neural progenitor cells. We show that cytoplasmic STI1 directly interacts with the GTPase Rnd1. This interaction is specific for the Rnd1 member of the Rnd family. In the COS collapse assay, overexpression of STI1 prevents Rnd1–plexin-A1-mediated cytoskeleton retraction. In PC-12 cells, overexpression of STI1 enhances neurite outgrowth in cellular processes initially established by Rnd1. Therefore, we propose that STI1 participates in Rnd1-induced signal transduction pathways that are involved in the dynamics of the actin cytoskeleton. 相似文献
873.
The integration of extrinsic and intrinsic signals is required to preserve the self-renewal and tissue regenerative capacity of adult stem cells, while protecting them from malignant conversion or loss of proliferative potential by death, differentiation or senescence. Here we review emerging signaling circuitries regulating stem cell fate, with emphasis on epithelial stem cells. Wnt, mTOR, GPCRs, Notch, Rho GTPases, YAP and DNA and histone methylases are some of the mechanisms that allow stem cells to balance their regenerative potential and the initiation of terminal differentiation programs, guaranteeing appropriate tissue homeostasis. Understanding the signaling circuitries regulating stem cell fate decisions might provide important insights into cancer initiation and numerous human pathologies that involve the progressive loss of tissue-specific adult stem cells. 相似文献
874.
Yeferson de Jesús López Medina Yordi Sebastián Tamayo-Molina Juan Felipe Valdés-López Silvio Urcuqui-Inchima 《化学与生物多样性》2023,20(8):e202300192
Infection by viruses Chikungunya (CHIKV) and Zika (ZIKV) continue to be serious problems in tropical and subtropical areas of the world. Here, we evaluated the antiviral and virucidal activity of caffeine against CHIKV and ZIKV in Vero, A549, and Huh-7 cell lines. Results showed that caffeine displays antiviral properties against both viruses. By pre-and post-infection treatment, caffeine significantly inhibited CHIKV and ZIKV replication in a dose-dependent manner. Furthermore, caffeine showed a virucidal effect against ZIKV. Molecular docking suggests the possible binding of caffeine with envelope protein and RNA-dependent RNA polymerase of CHIKV and ZIKV. This is the first study that showed an antiviral effect of caffeine against CHIKV and ZIKV. Although further studies are needed to better understand the mechanism of caffeine-mediated repression of viral replication, caffeine appears to be a promising compound that could be used for in vivo studies, perhaps in synergy with other compounds present in daily beverages. 相似文献
875.
876.
Claudio Laquatra Carlos Sanchez-Martin Alberto Dinarello Giuseppe Cannino Giovanni Minervini Elisabetta Moroni Marco Schiavone Silvio Tosatto Francesco Argenton Giorgio Colombo Paolo Bernardi Ionica Masgras Andrea Rasola 《Cell death & disease》2021,12(5)
The mitochondrial paralog of the Hsp90 chaperone family TRAP1 is often induced in tumors, but the mechanisms controlling its expression, as well as its physiological functions remain poorly understood. Here, we find that TRAP1 is highly expressed in the early stages of Zebrafish development, and its ablation delays embryogenesis while increasing mitochondrial respiration of fish larvae. TRAP1 expression is enhanced by hypoxic conditions both in developing embryos and in cancer models of Zebrafish and mammals. The TRAP1 promoter contains evolutionary conserved hypoxic responsive elements, and HIF1α stabilization increases TRAP1 levels. TRAP1 inhibition by selective compounds or by genetic knock-out maintains a high level of respiration in Zebrafish embryos after exposure to hypoxia. Our data identify TRAP1 as a primary regulator of mitochondrial bioenergetics in highly proliferating cells following reduction in oxygen tension and HIF1α stabilization.Subject terms: Cancer metabolism, Cell signalling 相似文献
877.
Summary The filum terminale, or terminal portion of the spinal cord, was studied in normal adult frogs (Rana pipiens) by means of light and electron microscopy. Astroglial cells are the predominant elements in this region. The rostral portion of the filum terminale consists mainly of (1) a peripheral dense ring of myelinated and some unmyelinated nerve fibers, and processes of astrocytes terminating at the subpial space; (2) an intermediate zone, in which astrocytes are the main cellular elements in addition to a few degenerated neurons; and (3) a central region where the central canal is lined by dark and light ependymal cells. In the caudal portion of the filum terminale, the amount of neuropil is greatly reduced. This region is formed mainly by astrocytic glial cells and very few neuronal elements. The central canal in the caudal portion is located ventrally and contains a lining consisting almost exclusively of dark ependymal cells. 相似文献
878.
Carmelo Tassj Silvio Dottorini Giorgio Scalise Nadia Geranio 《International journal for parasitology》1981,11(1):85-88
Tassi Carmelo, Dottorini Silvio, Scalise Giorgio and Geranio Nadia. 1981. Echinococcus granulosus: diagnosis of human hydatid disease by the Indirect Haemoagglutination reaction with antigens from hydatid fluid and scoleces. International Journal for Parasitology11: 85–88. Various antigenic fractions were prepared from sheep hydatid fluid and scoleces of Echinococcus granulosus by ammonium sulphate salting out. Sheep red blood cells were sensitized with all antigenic preparations and tested, by Indirect Haemoagglutination reaction, against 63 sera from humans with hydatid disease and 163 controls. The greatest sensitivity was obtained with the ‘0·8 M fraction’ and ‘Band 7’ from hydatid fluid. The specificity was excellent for all antigens examined. 相似文献
879.
Silvio Fici 《Kew Bulletin》2011,66(2):299-301
A new species of Capparis, C. tchaourembensis Fici, is described and illustrated. Its conservation status is assessed and its affinities with related taxa are discussed. 相似文献
880.