Extending Virial Black Hole Mass Estimates to Low-Luminosity or Obscured AGN: the cases of NGC 4395 and MCG -01-24-012

In the last decade, using single epoch (SE) virial based spectroscopic optical observations, it has been possible to measure the black hole (BH) mass on large type 1 Active Galactic Nuclei (AGN) samples. However this kind of measurements can not be applied on those obscured type 2 and/or low luminosity AGN where the nuclear component does not dominate in the optical. We have derived new SE relationships, based on the FWHM and luminosity of the broad line region component of the Pabeta emission line and/or the hard X-ray luminosity in the 14-195 keV band, which have the prospect of better working with low luminosity or obscured AGN. The SE relationships have been calibrated in the 10^5-10^9 M_sol mass range, using a sample of AGN whose BH masses have been previously measured using reverberation mapping techniques. Our tightest relationship between the reverberation-based BH mass and the SE virial product has an intrinsic spread of 0.20 dex. Thanks to these SE relations, in agreement with previous estimates, we have measured a BH mass of M_BH =1.7^+1.3_-0.7 X 10^5 M_sol for the low luminosity, type 1, AGN NGC 4395 (one of the smallest active galactic BH known). We also measured, for the first time, a BH mass of M_BH = 1.5^+1.1_-0.6 X 10^7 M_sol for the Seyfert 2 galaxy MCG -01-24-012.Comment: 10 pages, 7 figures. Accepted by MNRA

The obscured X-ray source population in the HELLAS2XMM survey: the Spitzer view

Recent X-ray surveys have provided a large number of high-luminosity, obscured Active Galactic Nuclei (AGN), the so-called Type 2 quasars. Despite the large amount of multi-wavelength supporting data, the main parameters related to the black holes harbored in such AGN are still poorly known. Here we present the results obtained for a sample of eight Type 2 quasars in the redshift range 0.9-2.1 selected from the HELLAS2XMM survey, for which we used Ks-band, Spitzer IRAC and MIPS data at 24 micron to estimate bolometric corrections, black hole masses, and Eddington ratios.Comment: 6 pages, to appear in "The Multicoloured Landscape of Compact Objects and their Explosive Progenitors: Theory vs Observations" (Cefalu, Sicily, June 2006). Eds. L. Burderi et al. (New York: AIP

Malignant pilomatricoma with multiple bone metastases in a dog: Histological and immunohistochemical study

An eleven year-old mongrel dog was referred with a history of left forelimb lameness and an ulcerated mass on the neck. Histologically, the cutaneous neoplasm revealed cystic lobules composed of basaloid cells with abrupt transition to central keratotic material, containing pycnotic and shadow cells. Approximately 3 months after primary diagnosis, a lesion of the cortical bone on the left humerus was observed using X-ray. Samples obtained from the humerus were processed for histopathological examination and the neoplastic tissue was observed to be similar to the type identified in the neck. Based on these findings, the tumor was diagnosed as a malignant pilomatricoma (MP) with bone metastasis. MP is a rare skin tumor that originates from hair matrix cells. To date, only nine reports have been presented in dogs. In the present study, we discuss the cytological and histological patterns of MP, confirmed by immunohistochemistry using β catenin antibody

Enhancement of 5-FU sensitivity by the proapoptotic rpL3 gene in p53 null colon cancer cells through combined polymer nanoparticles

Colon cancer is one of the leading causes of cancer-related death worldwide and the therapy with 5-fluorouracil (5-FU) is mainly limited due to resistance. Recently, we have demonstrated that nucleolar stress upon 5-FU treatment leads to the activation of ribosome-free rpL3 (L3) as proapoptotic factor. In this study, we analyzed L3 expression profile in colon cancer tissues and demonstrated that L3 mRNA amount decreased with malignant progression and the intensity of its expression was inversely related to tumor grade and Bcl-2/Bax ratio. With the aim to develop a combined therapy of 5-FU plus plasmid encoding L3 (pL3), we firstly assessed the potentiation of the cytotoxic effect of 5-FU on colon cancer cells by L3. Next, 10 μM 5-FU and 2 μg of pL3 were encapsulated in biocompatible nanoparticles (NPs) chemically conjugated with HA to achieve active tumor-targeting ability in CD44 overexpressing cancer cells. We showed the specific intracellular accumulation of NPs in cells and a sustained release for 5-FU and L3. Analysis of cytotoxicity and apoptotic induction potential of combined NPs clearly showed that the 5-FU plus L3 were more effective in inducing apoptosis than 5-FU or L3 alone. Furthermore, we show that the cancer-specific chemosensitizer effect of combined NPs may be dependent on L3 ability to affect 5-FU efflux by controlling P-gp (P-glycoprotein) expression. These results led us to propose a novel combined therapy with the use of 5-FU plus L3 in order to establish individualized therapy by examining L3 profiles in tumors to yield a better clinical outcomes

From `bathtub' galaxy evolution models to metallicity gradients

We model gas-phase metallicity radial profiles of galaxies in the local Universe by building on the `bathtub' chemical evolution formalism - where a galaxy's gas content is determined by the interplay between inflow, star formation, and outflows. In particular, we take into account inside-out disc growth and add physically motivated prescriptions for radial gradients in star formation efficiency (SFE). We fit analytical models against the metallicity radial profiles of low-redshift star-forming galaxies in the mass range log (M⋆/M⊙) = [9.0-11.0] derived by Belfiore et al., using data from the MaNGA survey. The models provide excellent fits to the data and are capable of reproducing the change in shape of the radial metallicity profiles, including the flattening observed in the centres of massive galaxies. We derive the posterior probability distribution functions for the model parameters and find significant degeneracies between them. The parameters describing the disc assembly time-scale are not strongly constrained from the metallicity profiles, while useful constrains are obtained for the SFE (and its radial dependence) and the outflow loading factor. The inferred value for the SFE is in good agreement with observational determinations. The inferred outflow loading factor is found to decrease with stellar mass, going from nearly unity at log (M⋆/M⊙) = 9.0 to close to zero at log (M⋆/M⊙) = 11.0, in general agreement with previous empirical determinations. These values are the lowest we can obtain for a physically motivated choice of initial mass function and metallicity calibration. We explore alternative choices which produce larger loading factors at all masses, up to order unity at the high-mass end

Pluronic® P123/F127 mixed micelles delivering sorafenib and its combination with verteporfin in cancer cells

Here, we developed Pluronic® P123/F127 (poloxamer) mixed micelles for the intravenous delivery of the anticancer drug sorafenib (SRB) or its combination with verteporfin (VP), a photosensitizer for photodynamic therapy that should complement well the cytotoxicity profile of the chemotherapeutic. SRB loading inside the core of micelles was governed by the drug:poloxamer weight ratio, while in the case of the SRB-VP combination, a mutual interference between the two drugs occurred and only specific ratios could ensure maximum loading efficiency. Coentrapment of SRB did not alter the photophysical properties of VP, confirming that SRB did not participate in any bimolecular process with the photosensitizer. Fluorescence resonance energy-transfer measurement of micelles in serum protein-containing cell-culture medium demonstrated the excellent stability of the system in physiologically relevant conditions. These results were in line with the results of the release study showing a release rate of both drugs in the presence of proteins slower than in phosphate buffer. SRB release was sustained, while VP remained substantially entrapped in the micelle core. Cytotoxicity studies in MDA-MB231 cells revealed that at 24 hours, SRB-loaded micelles were more active than free SRB only at very low SRB concentrations, while at 24+24 hours a prolonged cytotoxic effect of SRB-loaded micelles was observed, very likely mediated by the block in the S phase of the cell cycle. The combination of SRB with VP under light exposure was less cytotoxic than both the free combination and VP-loaded micelles + SRB-loaded micelles combination. This behavior was clearly explainable in terms of micelle uptake and intracellular localization. Besides the clear advantage of delivering SRB in poloxamer micelles, our results provide a clear example that each photochemotherapeutic combination needs detailed investigations on their particular interaction, and no generalization on enhanced cytotoxic effects should be derived a priori

BH mass scaling relations: the case of local AGN2

Black hole mass and bulge luminosity relation in type 2 AG

First constraints of dense molecular gas at z~7.5 from the quasar P\=oniu\=a'ena

We report the detection of CO(6-5) and CO(7-6) and their underlying continua from the host galaxy of quasar J100758.264+211529.207 (P\=oniu\=a'ena) at z=7.5419, obtained with the NOrthern Extended Millimeter Array (NOEMA). P\=oniu\=a'ena belongs to the HYPerluminous quasars at the Epoch of ReionizatION (HYPERION) sample of 17 $z>6$ quasars selected to be powered by supermassive black holes (SMBH) which experienced the fastest mass growth in the first Gyr of the Universe. The one reported here is the highest-redshift measurement of the cold and dense molecular gas to date. The host galaxy is unresolved and the line luminosity implies a molecular reservoir of $\rm M(H_2)=(2.2\pm0.2)\times 10^{10}$ $\rm M_\odot$, assuming a CO spectral line energy distribution typical of high-redshift quasars and a conversion factor $\alpha=0.8$ $\rm M_{\odot} (K\,km \, s^{-1} \,pc^{2})^{-1}$. We model the cold dust spectral energy distribution (SED) to derive a dust mass of M$_{\rm dust} =(2.1\pm 0.7)\times 10^8$ $\rm M_\odot$, and thus a gas to dust ratio $\sim100$. Both the gas and dust mass are not dissimilar from the reservoir found for luminous quasars at $z\sim6$. We use the CO detection to derive an estimate of the cosmic mass density of $\rm H_2$, $\Omega_{H_2} \simeq 1.31 \times 10^{-5}$. This value is in line with the general trend suggested by literature estimates at $z < 7$ and agrees fairly well with the latest theoretical expectations of non-equilibrium molecular-chemistry cosmological simulations of cold gas at early times.Comment: Submitted to ApJ Letter

Accurate dust temperature and star formation rate in the most luminous z>6z>6 quasar in the HYPerluminous quasars at the Epoch of ReionizatION (HYPERION) sample

We present ALMA Band 9 continuum observation of the ultraluminous quasi-stellar object (QSO) SDSS J0100+2802, providing a $\sim 10\sigma$ detection at $\sim 670$ GHz. SDSS J0100+2802 is the brightest QSO with the most massive super massive black hole (SMBH) known at $z>6$, and we study its dust spectral energy distribution in order to determine the dust properties and the star formation rate (SFR) of its host-galaxy. We obtain the most accurate estimate so far of the temperature, mass and emissivity index of the dust, having $T_{\rm dust}=48.4\pm2.3$ K, $M_{\rm dust}=(2.29\pm0.83)\times 10^7$ M$_\odot$, $\beta=2.63\pm 0.23$. This allows us to measure the SFR with the smallest statistical error for this QSO, SFR$=265\pm 32\ \rm M_\odot yr^{-1}$. Our results enable us to evaluate the relative growth of the SMBH and host galaxy of J0100+2802, finding that the SMBH is dominating the process of BH-galaxy growth in this QSO at $z=6.327$, when the Universe was $865$ Myr old. Such unprecedented constraints on the host galaxy SFR and dust temperature can only be obtained through high frequency observations, and highlight the importance of ALMA Band 9 to obtain a robust overview of the build-up of the first quasars' host galaxies at $z>6$.Comment: 10 pages, 4 figures, 1 table. Accepted for publication in ApJ