Aspetti epidemiologici della calcolosi di calcio in Italia: distribuzione dei fenotipi intermedi nella popolazione italiana

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Bcl-2 Regulates HIF-1α Protein Stabilization in Hypoxic Melanoma Cells via the Molecular Chaperone HSP90

Hypoxia-Inducible Factor 1 (HIF-1) is a transcription factor that is a critical mediator of the cellular response to hypoxia. Enhanced levels of HIF-1alpha, the oxygen-regulated subunit of HIF-1, is often associated with increased tumour angiogenesis, metastasis, therapeutic resistance and poor prognosis. It is in this context that we previously demonstrated that under hypoxia, bcl-2 protein promotes HIF-1/Vascular Endothelial Growth Factor (VEGF)-mediated tumour angiogenesis.By using human melanoma cell lines and their stable or transient derivative bcl-2 overexpressing cells, the current study identified HIF-1alpha protein stabilization as a key regulator for the induction of HIF-1 by bcl-2 under hypoxia. We also demonstrated that bcl-2-induced accumulation of HIF-1alpha protein during hypoxia was not due to an increased gene transcription or protein synthesis. In fact, it was related to a modulation of HIF-1alpha protein expression at a post-translational level, indeed its degradation rate was faster in the control lines than in bcl-2 transfectants. The bcl-2-induced HIF-1alpha stabilization in response to low oxygen tension conditions was achieved through the impairment of ubiquitin-dependent HIF-1alpha degradation involving the molecular chaperone HSP90, but it was not dependent on the prolyl hydroxylation of HIF-1alpha protein. We also showed that bcl-2, HIF-1alpha and HSP90 proteins form a tri-complex that may contribute to enhancing the stability of the HIF-1alpha protein in bcl-2 overexpressing clones under hypoxic conditions. Finally, by using genetic and pharmacological approaches we proved that HSP90 is involved in bcl-2-dependent stabilization of HIF-1alpha protein during hypoxia, and in particular the isoform HSP90beta is the main player in this phenomenon.We identified the stabilization of HIF-1alpha protein as a mechanism through which bcl-2 induces the activation of HIF-1 in hypoxic tumour cells involving the beta isoform of molecular chaperone HSP90

SoxF factors induce Notch1 expression via direct transcriptional regulation during early arterial development.

Arterial specification and differentiation are influenced by a number of regulatory pathways. While it is known that the Vegfa-Notch cascade plays a central role, the transcriptional hierarchy controlling arterial specification has not been fully delineated. To elucidate the direct transcriptional regulators of Notch receptor expression in arterial endothelial cells, we used histone signatures, DNaseI hypersensitivity and ChIP-seq data to identify enhancers for the human NOTCH1 and zebrafish notch1b genes. These enhancers were able to direct arterial endothelial cell-restricted expression in transgenic models. Genetic disruption of SoxF binding sites established a clear requirement for members of this group of transcription factors (SOX7, SOX17 and SOX18) to drive the activity of these enhancers in vivo Endogenous deletion of the notch1b enhancer led to a significant loss of arterial connections to the dorsal aorta in Notch pathway-deficient zebrafish. Loss of SoxF function revealed that these factors are necessary for NOTCH1 and notch1b enhancer activity and for correct endogenous transcription of these genes. These findings position SoxF transcription factors directly upstream of Notch receptor expression during the acquisition of arterial identity in vertebrates.This work was supported by the National Health and Medical Research Council of Australia (NHMRC) (APP1107643); The Cancer Council Queensland (1107631) (M.Fran.); the Australian Research Council Discovery Project (DP140100485) and a Career Development Fellowship (APP1111169) (M.Fran.); the Ludwig Institute for Cancer Research (M.Frit., A.N., I.R., S.D.V.); the Medical Research Council (MR/J007765/1) (K.L., G.B.-G., S.D.V.); the Fondazione Cariplo (2011-0555) (M.B., B.H., M.Fran.); and the Biotechnology and Biological Sciences Research Council (BB/L020238/1) (A.N., K.L., G.B.-G., S.D.V.)

Gamma-Ray Burst observations by the high-energy charged particle detector on board the CSES-01 satellite between 2019 and 2021

In this paper we report the detection of five strong Gamma-Ray Bursts (GRBs) by the High-Energy Particle Detector (HEPD-01) mounted on board the China Seismo-Electromagnetic Satellite (CSES-01), operational since 2018 on a Sun-synchronous polar orbit at a $\sim$ 507 km altitude and 97$^\circ$ inclination. HEPD-01 was designed to detect high-energy electrons in the energy range 3 - 100 MeV, protons in the range 30 - 300 MeV, and light nuclei in the range 30 - 300 MeV/n. Nonetheless, Monte Carlo simulations have shown HEPD-01 is sensitive to gamma-ray photons in the energy range 300 keV - 50 MeV, even if with a moderate effective area above $\sim$ 5 MeV. A dedicated time correlation analysis between GRBs reported in literature and signals from a set of HEPD-01 trigger configuration masks has confirmed the anticipated detector sensitivity to high-energy photons. A comparison between the simultaneous time profiles of HEPD-01 electron fluxes and photons from GRB190114C, GRB190305A, GRB190928A, GRB200826B and GRB211211A has shown a remarkable similarity, in spite of the different energy ranges. The high-energy response, with peak sensitivity at about 2 MeV, and moderate effective area of the detector in the actual flight configuration explain why these five GRBs, characterised by a fluence above $\sim$ 3 $\times$ 10$^{-5}$ erg cm$^{-2}$ in the energy interval 300 keV - 50 MeV, have been detected.Comment: Accepted for publication in The Astrophysical Journal (ApJ

Nonspecific immune response in fish fed glucan diets prior to induced transportation stress

The present research studied the effects of feeding diets containing different doses of glucan on stress prevention in rainbow trout (Oncorhynchus mykiss). Different concentrations of glucan (0, 0.1, 0.5 or 1.0%) were administered to the fish over a 4-week period, then the fish were stressed by being transported for 2h. The effect of stress on the efficiency of the immune response was studied by measuring alterations of the following parameters: number and composition of the leucocyte population, phagocytosis and respiratory burst activity. At the end of the treatment, glucan-fed trout had increased levels of phagocytosis and oxidative radical production, but the data could not be correlated with the different dietary concentrations of glucan. Respiratory burst and phagocytosis appeared significantly reduced in stressed groups. The reduction was more evident in the control group, but no differences were detected between groups fed different diets. Transportation stress increased phagocytosis activity, but for control fish and fish fed 1.0% glucan it did not reach the levels observed before stress. Feeding glucan apparently induced a slight degeneration of the epithelial cells in the stomach and gut mucosae

Different doses of consensus interferon plus ribavirin in patients with hepatitis C virus genotype 1 relapsed after interferon monotherapy: a randomized controlled trial

AIM: To assess the efficacy of different schedules of consensus interferon (CIFN) plus ribavirin in retreating chronic hepatitis C patients who relapsed after recombinant interferon (rIFN) monotherapy. METHODS: Forty-five patients (34 males and 11 females) with chronic hepatitis due to hepatitis C virus (HCV) genotype 1 who relapsed after a previous course of rIFN monotherapy were randomized to receive 9 μg CIFN three times per week for 52 wk (group A, n = 22) or 18 μg CIFN three times per week for 52 wk (group B, n = 23) in combination with ribavirin 800 to 1200 mg daily for 52 wk (according to body weight). Virological response was evaluated at week 24 (EVR), at the end of treatment (ETR) and at 76 wk (SVR). RESULTS: By intention-to-treat analysis, subjects in group A had an EVR in 35% of cases, an ETR in 35% and a SVR in 27.3% of cases. Subjects in group B had an EVR in 32% of cases, an ETR in 35% and a SVR in 26.1% of cases. Treatment was stopped because of adverse effects (mostly intolerance) in 15 patients (6 in group A and 9 in group B). IFN dose reduction was needed in 2 patients (1 in group A and 1 in group B). Ribavirin dose was reduced in 2 patients in group A and 1 in group B respectively. Among the 15 subjects who received at least 80% of the intended schedule, the rate of SVR was 80% (6 in group A and 6 in group B). CONCLUSION: CIFN in combination with ribavirin when given to HCV genotype 1 relapsers after rIFN monotherapy obtains an unsatisfactory rate of sustained viral clearance independently of dosage of the drug. This may be due to its scarce tolerability

Cuprizone neurotoxicity, copper deficiency and neurodegeneration

Cuprizone is used to obtain demyelination in mice. Cuprizone-treated mice show symptoms similar to several neurodegenerative disorders such as severe status spongiosus. Although it has a simple chemical formula, its neurotoxic mechanism is still unknown. In this work, we examined both physico\u2013chemical properties and biological effects of cuprizone. Our results indicate that cuprizone has very complicated and misunderstood solution chemistry. Moreover, we show here the inability of cuprizone to cross neither the intestinal epithelial barrier nor the neuronal cell membrane, as well its high tolerability by cultured neurons. If added to mice diet, cuprizone does not accumulate in liver or in brain. Therefore, its neurotoxic effect is explainable only in terms of its capability to chelate copper, leading to chronic copper deficiency

Cuprizone neurotoxicity, copper deficiency and neurodegeneration

Cuprizone is used to obtain demyelination in mice. Cuprizone-treated mice show symptoms similar to several neurodegenerative disorders such as severe status spongiosus. Although it has a simple chemical formula, its neurotoxic mechanism is still unknown. In this work, we examined both physico-chemical properties and biological effects of cuprizone. Our results indicate that cuprizone has very complicated and misunderstood solution chemistry. Moreover, we show here the inability of cuprizone to cross neither the intestinal epithelial barrier nor the neuronal cell membrane, as well its high tolerability by cultured neurons. If added to mice diet, cuprizone does not accumulate in liver or in brain. Therefore, its neurotoxic effect is explainable only in terms of its capability to chelate copper, leading to chronic copper deficiency. (C) 2010 Elsevier Inc. All rights reserved

Structural flexibility and role of vicinal 2-thienyl rings in 2,3-dicyano-5,6-di(2-thienyl)-1,4-pyrazine, [(CN)2Th2Pyz], Its palladium(II) complex [(CN)2Th2Pyz(PdCl 2)2], and the related pentametallic pyrazinoporphyrazines [(PdCl2)4Th8TPyzPzM] (M = Mg II(H2O), ZnII)

The solid state and solution structure of 2,3-dicyano-5,6-di(2-thienyl)-1, 4-pyrazine, [(CN)2Th2Pyz], and its PdII derivative, [(CN)2Th2Pyz(PdCl2) 2]•H2O, formed by reaction of [(CN) 2Th2Pyz] with [(C6H5CN) 2PdCl2] were characterized by X-ray, UV-visible, 1H and 13C NMR, and extended X-ray absorption fine structure (EXAFS) spectral measurements. The X-ray crystal structure of [(CN)2Th2Pyz] shows the presence of one thienyl ring positioned orthogonal to the rest of the molecule, with the two vicinal thienyl rings lying orthogonal to each other in a rare arrangement. NMR studies of [(CN)2Th2Pyz] in the solid state and in solutions of dimethylformamide or dimethyl sulfoxide confirm a nonequivalence of the thienyl rings in the solid state and also in solution. EXAFS results indicate that two distinct PdII coordination sites are formed at the di(2-thienyl)pyrazino moiety of [(CN)2Th2Pyz(PdCl 2)2]•H2O, with identical Pd-N pyz (2.03(3) Å) and Pd-Cl (2.36(3) Å) bond lengths but with different Pd-S1 (2.25(4) Å) and Pd-S2 (3.21(5) Å) bond distances in an overall asymmetric molecular framework. Density functional theory (DFT) and time-dependent DFT (TDDFT) theoretical studies also provide information about the structure and spectral behavior of the precursor and its metalated PdII derivative. 1H/13C NMR and UV-visible spectral measurements were also carried out on two heteropentametallic porphyrazine macrocycles which were prepared by a reaction of PdCl2 with [Th8TPyzPzM] where Th8TPyzPz = tetrakis-2,3-[5,6-di-(2-thienyl)-pyrazino]porphyrazinato dianion and M = Mg II(H2O) or ZnII. Spectroscopic data on the newly synthesized [(PdCl2)4Th8TPyzPzM] compounds suggest that the binding of PdCl2 involves coordination sites of the type S2(th)PdCl2 with the two thienyl rings of each di(2-thienyl)pyrazino fragment bound to PdII in an equivalent manner ("th-th" coordination). This is similar to what was found for the corresponding octapyridinated analogues ("py-py" coordination). © 2011 American Chemical Society