Calibrating hydrogen-rich core-collapse supernovae for their use as distance indicators independently of type Ia supernovae

Using our new general-relativistic, radiation hydrodynamics, Lagrangian code, we computed a rather extended grid of hydrogen-rich core-collapse supernova (CC-SN) models and explored the potentials of their "standardization" as distance indicators. We discuss the properties of some calibrations previously reported in the literature and present new correlations based on the behavior of the light curve, that can be employed for calibrating hydrogen-rich CC-SNe using only photometric data.Comment: 2 pages, 3 figures, to appear in Proceedings of IAU Symp. 281, Binary Paths to Type Ia Supernovae Explosions, ed. R. Di Stefano and M. Ori

Methylation status of Dnmt1 promoter depends on poly(ADP-ribosy)lation

Research is focused on CpG islands and on the mechanism that poly(ADP-ribosyl)ation uses to defend the unmethylated state of these important DNA sequences which are located in the promoter regions of the housekeeping genes having a role of transcription regulators. Data here reported show that inhibition of PARP activity allows the diffuse insertion of methyl groups onto some CpG islands and in particular on the CpG island which is located in the promoter region of Dnmt1 gene. Hence, following inhibition of PARPs activity, this promoter loses its protection against methylation becoming silenced through methylation as shown by analyses with Methylation Sensitive PCR (MS-PCR) and sequencing after bisulphite treatment. Analyses of Western Blotting, RT-PCR and Real-time RT-PCR confirm that the gene has undergone silencing. The role of ADP-ribose polymers in silencing Dnmt1 has been demonstrated by additional experiments in which overexpression of poly(ADP-ribose) glycohydrolase leads to reduction of ADP-ribose polymers in nuclei associated to a sharp decrease of Dnmt1 level respect to control. A parallel genome-wide methyl-sensitive restriction assay demonstrates that the variation of Dnmt1 level is followed by a bimodal alteration of DNA methylation pattern. In fact, the inhibition of poly(ADP-ribosyl)ation initially causes an increase in methyl-group insertion onto DNA while this phenomenon is reversed after prolonged treatments and demethylation is detected within Alu sequences. Considering the important role played by Dnmt1 in the epigenetic scenario, these data lead us to think about what happens in tumor cells where both anomalous methylation of some CpG islands and diffuse hypomethylation are present. These findings open up a new path into epigenetic research in tumors. What is remarkable is that the demethylated pattern found in Alu sequences after treatment of cells with 3-ABA for 96 hours is very similar to the one found on DNA from cells treated with 5-AZA for the same time. The discovery of a DNA demethylating activity dependent on the use of inhibitors of poly(ADP-ribosyl)ation process increases the knowledge of mechanism by which these inhibitors enhance the cytotoxicity of other anticancer agents

Weak instability of Hamiltonian equilibria

This is an expository paper on Lyapunov stability of equilibria of autonomous Hamiltonian systems. Our aim is to clarify the concept of weak instability, namely instability without non-constant motions which have the equilibrium as limit point as time goes to minus infinity. This is done by means of some examples. In particular, we show that a weakly unstable equilibrium point can be stable for the linearized vector field

Methylation status of Dnmt1 promoter depends on poly(ADP-ribosy)lation

Research is focused on CpG islands and on the mechanism that poly(ADP-ribosyl)ation uses to defend the unmethylated state of these important DNA sequences which are located in the promoter regions of the housekeeping genes having a role of transcription regulators. Data here reported show that inhibition of PARP activity allows the diffuse insertion of methyl groups onto some CpG islands and in particular on the CpG island which is located in the promoter region of Dnmt1 gene. Hence, following inhibition of PARPs activity, this promoter loses its protection against methylation becoming silenced through methylation as shown by analyses with Methylation Sensitive PCR (MS-PCR) and sequencing after bisulphite treatment. Analyses of Western Blotting, RT-PCR and Real-time RT-PCR confirm that the gene has undergone silencing. The role of ADP-ribose polymers in silencing Dnmt1 has been demonstrated by additional experiments in which overexpression of poly(ADP-ribose) glycohydrolase leads to reduction of ADP-ribose polymers in nuclei associated to a sharp decrease of Dnmt1 level respect to control. A parallel genome-wide methyl-sensitive restriction assay demonstrates that the variation of Dnmt1 level is followed by a bimodal alteration of DNA methylation pattern. In fact, the inhibition of poly(ADP-ribosyl)ation initially causes an increase in methyl-group insertion onto DNA while this phenomenon is reversed after prolonged treatments and demethylation is detected within Alu sequences. Considering the important role played by Dnmt1 in the epigenetic scenario, these data lead us to think about what happens in tumor cells where both anomalous methylation of some CpG islands and diffuse hypomethylation are present. These findings open up a new path into epigenetic research in tumors. What is remarkable is that the demethylated pattern found in Alu sequences after treatment of cells with 3-ABA for 96 hours is very similar to the one found on DNA from cells treated with 5-AZA for the same time. The discovery of a DNA demethylating activity dependent on the use of inhibitors of poly(ADP-ribosyl)ation process increases the knowledge of mechanism by which these inhibitors enhance the cytotoxicity of other anticancer agents

Involutions of real intervals

This paper shows a simple construction of the continuous involutions of real intervals in terms of the continuous even functions. We also study the smooth involutions defined by symmetric equations. Finally, we review some applications, in particular the characterization of the isochronous potentials by means of smooth involutions

Rise and fall of Achille de Giovanni\u2019s clinical anthropometry

Achille de Giovanni (1838-1916), Italian clinician and pathologist, developed a constitutional method for clinical investigations based on the morphology of the human body. He was the first to use anthropometry with living patients with the aim of evaluating the relationship between form and function, between organic structures, physiology and pathology, for understanding \u201cindividuality\u201d in a scientific way. His clinical anthropometry gained some popularity during his life, but was completely forgotten few decades after his death. By consequence, he can be considered a loser from the point of view of the long-term impact of his theories and practices, but at the same time, some of his ideas could be still valid today