We report the discovery of a new 21-cm HI absorption system using
commissioning data from the Boolardy Engineering Test Array of the Australian
Square Kilometre Array Pathfinder (ASKAP). Using the ...711.5 - 1015.5 MHz band of
ASKAP we were able to conduct a blind search for the 21-cm line in a continuous
redshift range between $z = 0.4$ and 1.0, which has, until now, remained
largely unexplored. The absorption line is detected at $z = 0.44$ towards the
GHz-peaked spectrum radio source PKS B1740$-$517 and demonstrates ASKAP's
excellent capability for performing a future wide-field survey for HI
absorption at these redshifts. Optical spectroscopy and imaging using the
Gemini-South telescope indicates that the HI gas is intrinsic to the host
galaxy of the radio source. The narrow OIII emission lines show clear
double-peaked structure, indicating either large-scale outflow or rotation of
the ionized gas. Archival data from the \emph{XMM-Newton} satellite exhibit an
absorbed X-ray spectrum that is consistent with a high column density obscuring
medium around the active galactic nucleus. The HI absorption profile is
complex, with four distinct components ranging in width from 5 to 300 km
s$^{-1}$ and fractional depths from 0.2 to 20 per cent. In addition to systemic
HI gas, in a circumnuclear disc or ring structure aligned with the radio jet,
we find evidence for a possible broad outflow of neutral gas moving at a radial
velocity of $v \sim 300$ km s$^{-1}$. We infer that the expanding young radio
source ($t_{\rm age} \approx 2500$ yr) is cocooned within a dense medium and
may be driving circumnuclear neutral gas in an outflow of $\sim$ 1
$\mathrm{M}_{\odot}$ yr$^{-1}$.
We present HI imaging of the galaxy group IC 1459 carried out with six antennas of the Australian SKA Pathfinder equipped with phased-array feeds. We detect and resolve HI in eleven galaxies down to ...a column density of \(\sim10^{20}\) cm\(^{-2}\) inside a ~6 deg\(^2\) field and with a resolution of ~1 arcmin on the sky and ~8 km/s in velocity. We present HI images, velocity fields and integrated spectra of all detections, and highlight the discovery of three HI clouds -- two in the proximity of the galaxy IC 5270 and one close to NGC 7418. Each cloud has an HI mass of \(10^9\) M\(_\odot\) and accounts for ~15% of the HI associated with its host galaxy. Available images at ultraviolet, optical and infrared wavelengths do not reveal any clear stellar counterpart of any of the clouds, suggesting that they are not gas-rich dwarf neighbours of IC 5270 and NGC 7418. Using Parkes data we find evidence of additional extended, low-column-density HI emission around IC 5270, indicating that the clouds are the tip of the iceberg of a larger system of gas surrounding this galaxy. This result adds to the body of evidence on the presence of intra-group gas within the IC 1459 group. Altogether, the HI found outside galaxies in this group amounts to several times \(10^9\) M\(_\odot\), at least 10% of the HI contained inside galaxies. This suggests a substantial flow of gas in and out of galaxies during the several billion years of the group's evolution.
Phospholipase A2 has been considered to play a role in physiological membrane turnover in cardiac tissue and in the degradation of membrane lipids under pathophysiological conditions, such as ...ischemia and reperfusion. We report the cloning of a cDNA encoding a member of the Ca2+-dependent, low molecular mass phospholipase A2 (PLA2) present in rat heart. The cDNA predicts a mature protein of 146 amino acid residues including a 21 amino acid sequence at the N-terminal end, which has the features characteristic of eukaryotic secretory signal peptides. The deduced amino acid sequence constitutes an enzyme of the group II class of PLA2s, and resembles PLA2s from other mammalian sources. A Northern blot analysis performed to determine the tissue distribution showed that rat ileum contains the largest amount of the PLA2 transcript among the tissues examined, a weaker signal was present in heart, spleen and soleus muscle, and no signal could be detected in EDL muscle, stomach, liver, kidney, brain and lung. Northern blot analysis and reverse transcriptase-polymerase chain reaction (RT-PCR) techniques indicate the presence of this enzyme in neonatal and adult rat cardiomyocytes and in a cultured rat cardiac fibroblast-like cell line, but not in rat cardiac-derived endothelial cell lines. Transcription levels of rat heart group II PLA2 in isolated neonatal rat cardiomyocytes were found to increase after stimulating the cells with tumor necrosis factor-alpha (TNF-alpha) or the alpha1-adrenergic agonist phenylephrine.
We report the discovery of a new 21-cm HI absorption system using commissioning data from the Boolardy Engineering Test Array of the Australian Square Kilometre Array Pathfinder (ASKAP). Using the ...711.5 - 1015.5 MHz band of ASKAP we were able to conduct a blind search for the 21-cm line in a continuous redshift range between \(z = 0.4\) and 1.0, which has, until now, remained largely unexplored. The absorption line is detected at \(z = 0.44\) towards the GHz-peaked spectrum radio source PKS B1740\(-\)517 and demonstrates ASKAP's excellent capability for performing a future wide-field survey for HI absorption at these redshifts. Optical spectroscopy and imaging using the Gemini-South telescope indicates that the HI gas is intrinsic to the host galaxy of the radio source. The narrow OIII emission lines show clear double-peaked structure, indicating either large-scale outflow or rotation of the ionized gas. Archival data from the \emph{XMM-Newton} satellite exhibit an absorbed X-ray spectrum that is consistent with a high column density obscuring medium around the active galactic nucleus. The HI absorption profile is complex, with four distinct components ranging in width from 5 to 300 km s\(^{-1}\) and fractional depths from 0.2 to 20 per cent. In addition to systemic HI gas, in a circumnuclear disc or ring structure aligned with the radio jet, we find evidence for a possible broad outflow of neutral gas moving at a radial velocity of \(v \sim 300\) km s\(^{-1}\). We infer that the expanding young radio source (\(t_{\rm age} \approx 2500\) yr) is cocooned within a dense medium and may be driving circumnuclear neutral gas in an outflow of \(\sim\) 1 \(\mathrm{M}_{\odot}\) yr\(^{-1}\).
More than half of the children and adolescents with malignant brain tumors will relapse following initial therapy. Irrespective of the therapeutic modalities the prognosis of patients with recurrent ...or metastatic brain tumors is still poor. New strategies such as high dose chemotherapy (HDCT) with autologous blood stem cell transplantation (ABSCT) offer the possibility to improve the longterm prognosis of these patients. Following conventional chemotherapy with carboplatin/etoposide and after achieving complete or partial remission (CR or PR) 10 patients aged from 3.2 to 25.5 years (median, 10.3 years) with refractory or recurrent malignant brain tumors (anaplastic astrocytoma/glioblastoma, n = 2; medulloblastoma/PNET, n = 6; ependymoma, n = 1; plexus carcinoma, n = 1) received in a pilot study one course of HDCT with ABSCT. The consolidation regimen consisted of thiotepa (400-600mg/m2/d, i.v. 6 h, d-9), carboplatin and etoposide (500mg/m2/d, CVI 24h, d-8 to d-5, respectively) and was followed by the retransfusion of autologous blood stem cells on day 0. Before starting HDCT 6 patients showed CR and 4 patients had PR or stable disease (SD). Following the HDCT 3 of the 4 patients with residual tumor had CR or PR. 6 patients have remained in continuous CR or SD 8 to 41 months (median 17.2 months) after the HDCT. 2 patients relapsed 8.5 and 9.5 months after HDCT and died from progressive disease. Two patients died therapy-related from systemic aspergillosis and were not evaluable for response. Hematological recovery with an absolute neutrophile count of > 0.5 x 10(9)/l and a platelet count of > 30 x 10(9)/l was reached on days +11 (median; range, +9 to +14) and +16 (median; range, +6 to +47), respectively. The main nonhematological toxic effects were infections, severe mucositis, and hyperbilirubinemia. Although the long-term efficacy of HDCT with ABSCT is still not evaluable and the toxicity of this regimen is high, a multicenter phase II trial seems to be justified in view of the poor prognosis of recurrent or refractory brain tumors in children and adolescents.
