Formation of Supermassive Black Holes

Evidence shows that massive black holes reside in most local galaxies. Studies have also established a number of relations between the MBH mass and properties of the host galaxy such as bulge mass and velocity dispersion. These results suggest that central MBHs, while much less massive than the host (~ 0.1%), are linked to the evolution of galactic structure. In hierarchical cosmologies, a single big galaxy today can be traced back to the stage when it was split up in hundreds of smaller components. Did MBH seeds form with the same efficiency in small proto-galaxies, or did their formation had to await the buildup of substantial galaxies with deeper potential wells? I briefly review here some of the physical processes that are conducive to the evolution of the massive black hole population. I will discuss black hole formation processes for `seed' black holes that are likely to place at early cosmic epochs, and possible observational tests of these scenarios.Comment: To appear in The Astronomy and Astrophysics Review. The final publication is available at http://www.springerlink.co

Slx8 removes Pli1-dependent protein-SUMO conjugates including SUMOylated Topoisomerase I to promote genome stability

Peer reviewedPublisher PD

Varespladib and cardiovascular events in patients with an acute coronary syndrome: the VISTA-16 randomized clinical trial

IMPORTANCE: Secretory phospholipase A2(sPLA2) generates bioactive phospholipid products implicated in atherosclerosis. The sPLA2inhibitor varespladib has favorable effects on lipid and inflammatory markers; however, its effect on cardiovascular outcomes is unknown. OBJECTIVE: To determine the effects of sPLA2inhibition with varespladib on cardiovascular outcomes. DESIGN, SETTING, AND PARTICIPANTS: A double-blind, randomized, multicenter trial at 362 academic and community hospitals in Europe, Australia, New Zealand, India, and North America of 5145 patients randomized within 96 hours of presentation of an acute coronary syndrome (ACS) to either varespladib (n = 2572) or placebo (n = 2573) with enrollment between June 1, 2010, and March 7, 2012 (study termination on March 9, 2012). INTERVENTIONS: Participants were randomized to receive varespladib (500 mg) or placebo daily for 16 weeks, in addition to atorvastatin and other established therapies. MAIN OUTCOMES AND MEASURES: The primary efficacy measurewas a composite of cardiovascular mortality, nonfatal myocardial infarction (MI), nonfatal stroke, or unstable angina with evidence of ischemia requiring hospitalization at 16 weeks. Six-month survival status was also evaluated. RESULTS: At a prespecified interim analysis, including 212 primary end point events, the independent data and safety monitoring board recommended termination of the trial for futility and possible harm. The primary end point occurred in 136 patients (6.1%) treated with varespladib compared with 109 patients (5.1%) treated with placebo (hazard ratio [HR], 1.25; 95%CI, 0.97-1.61; log-rank P = .08). Varespladib was associated with a greater risk of MI (78 [3.4%] vs 47 [2.2%]; HR, 1.66; 95%CI, 1.16-2.39; log-rank P = .005). The composite secondary end point of cardiovascular mortality, MI, and stroke was observed in 107 patients (4.6%) in the varespladib group and 79 patients (3.8%) in the placebo group (HR, 1.36; 95% CI, 1.02-1.82; P = .04). CONCLUSIONS AND RELEVANCE: In patients with recent ACS, varespladib did not reduce the risk of recurrent cardiovascular events and significantly increased the risk of MI. The sPLA2inhibition with varespladib may be harmful and is not a useful strategy to reduce adverse cardiovascular outcomes after ACS. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01130246. Copyright 2014 American Medical Association. All rights reserved

A review of the distribution of particulate trace elements in urban terrestrial environments and its application to considerations of risk

We review the evolution, state of the art and future lines of research on the sources, transport pathways, and sinks of particulate trace elements in urban terrestrial environments to include the atmosphere, soils, and street and indoor dusts. Such studies reveal reductions in the emissions of some elements of historical concern such as Pb, with interest consequently focusing on other toxic trace elements such as As, Cd, Hg, Zn, and Cu. While establishment of levels of these elements is important in assessing the potential impacts of human society on the urban environment, it is also necessary to apply this knowledge in conjunction with information on the toxicity of those trace elements and the degree of exposure of human receptors to an assessment of whether such contamination represents a real risk to the city’s inhabitants and therefore how this risk can be addressed

Exploring new physics frontiers through numerical relativity

The demand to obtain answers to highly complex problems within strong-field gravity has been met with significant progress in the numerical solution of Einstein's equations - along with some spectacular results - in various setups. We review techniques for solving Einstein's equations in generic spacetimes, focusing on fully nonlinear evolutions but also on how to benchmark those results with perturbative approaches. The results address problems in high-energy physics, holography, mathematical physics, fundamental physics, astrophysics and cosmology

An unexpected evolution of symptomatic mild middle cerebral artery (MCA) stenosis: asymptomatic occlusion

<p>Abstract</p> <p>Background</p> <p>The intracranial localization of large artery disease is recognized as the main cause of ischemic stroke in the world, considering all countries, although its global burden is widely underestimated. Indeed it has been reported more frequently in Asians and African-American people, but the finding of intracranial stenosis as a cause of ischemic stroke is relatively common also in Caucasians. The prognosis of patients with stroke due to intracranial steno-occlusion is strictly dependent on the time of recanalization. Moreover, the course of the vessel involvement is highly dynamic in both directions, improvement or worsening, although several data are derived from the atherosclerotic subtype, compared to other causes.</p> <p>Case description</p> <p>We report the clinical, neurosonological and neuroradiological findings of a young woman, who came to our Stroke Unit because of the abrupt onset of aphasia during her work. An urgent neurosonological examination showed a left M1 MCA stenosis, congruent with the presenting symptoms; magnetic resonance imaging confirmed this finding and identified an acute ischemic lesion on the left MCA territory. The past history of the patient was significant only for a hyperinsulinemic condition, treated with metformine, and a mild overweight. At this time a selective cerebral angiography was not performed because of the patient refusal and she was discharged on antiplatelet and lipid-lowering therapy, having failed to identify autoimmune or inflammatory diseases. Within 1 month, she went back to our attention because of the recurrence of aphasia, lasting about ten minutes. Neuroimaging findings were unchanged, but the patient accepted to undergo a selective cerebral angiography, which showed a mild left distal M1 MCA stenosis.</p> <p>During the follow-up the patient did not experienced any recurrence, but a routine neurosonological examination found an unexpected evolution of the known MCA stenosis, i.e. left M1 MCA occlusion. Neuroradiological imaging did not identify new lesions of the brain parenchyma and a repeated selective cerebral angiography confirmed the left M1 MCA occlusion.</p> <p>Conclusions</p> <p>Regardless of the role of metabolic and/or inflammatory factors on the aetiology of the intracranial stenosis in this case, the course of the vessel disease was unexpected and previously unreported in the literature at our knowledge.</p

Ki-1 Large Cell Lymphoma with Regressing Lesions in a Child

An 8-year-old boy was seen with a cutaneous Ki-1 anaplastic, large cell lymphoma with multiple lesions. Some of the lesions showed spontaneous regression. During more than seven years of disease no systemic Involvement was observed, but recurrent, self-healing lesions did appear. Histopathologic examination of five lesions revealed a variety of findings, from an inflammatory infiltrate to a highly anaplastic pattern. The neoplastic cells expressed Ki-1 and leukocyte common antigens. Ultrastructurally, those cells showed ruffled indentations. The differential diagnosis includes microvillous malignant lymphoma. The patient has had a four-year follow-up without relapses.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72895/1/j.1525-1470.1992.tb01226.x.pd

Laparoscopic anterior gastropexy for chronic recurrent gastric volvulus: a case report

<p>Abstract</p> <p>Introduction</p> <p>Gastric volvulus is an uncommon clinical entity, first described by Berti in 1866. It is a rotation of all or part of the stomach through more than 180°. This rotation can occur on the longitudinal (organo-axial) or transverse (mesentero-axial) axis. This condition can lead to a closed-loop obstruction or strangulation. Traditional surgical therapy for gastric volvulus is based on an open approach. Here we report the case of a patient with chronic intermittent gastric volvulus who underwent a successful laparoscopic treatment.</p> <p>Case presentation</p> <p>A 34-year-old woman presented with multiple episodes of recurrent upper abdominal pain associated with retching and vomiting, treated unsuccessfully with intramuscular metoclopramide. Endoscopic examination of the upper digestive tract showed a suspected rotation of the stomach, and a chronic recurrent gastric volvulus was revealed by barium meal. The patient was operated on successfully, with an anterior laparoscopic gastropexy performed as the first surgical approach.</p> <p>Conclusion</p> <p>Experience with laparoscopic anterior gastropexy is limited only to a few described cases. Our patient was clinically and radiologically followed-up for 2 years with no evidence of recurrence, either radiological or symptomatic. Based on this result, laparoscopic gastropexy can be seen and considered as an initial 'gold standard' for the treatment of gastric volvulus.</p

Rubia cordifolia, Fagonia cretica linn and Tinospora cordifolia exert neuroprotection by modulating the antioxidant system in rat hippocampal slices subjected to oxygen glucose deprivation

BACKGROUND: The major damaging factor during and after the ischemic/hypoxic insult is the generation of free radicals, which leads to apoptosis, necrosis and ultimately cell death. Rubia cordifolia (RC), Fagonia cretica linn (FC) and Tinospora cordifolia (TC) have been reported to contain a wide variety of antioxidants and have been in use in the eastern system of medicine for various disorders. However, their mechanism of action was largely unknown. We therefore selected these herbs for the present study to test their neuroprotective ability and the associated mechanism in rat hippocampal slices subjected to oxygen-glucose deprivation (OGD). METHODS: Hippocampal Slices were subjected to OGD (oxygen glucose deprivation) and divided into 3 groups: control, OGD and OGD + drug treated. Cytosolic Cu-Zn superoxide dismutase (Cu-Zn SOD), reduced glutathione (GSH), glutathione peroxidase (GPx), nitric oxide (NO) was measured as nitrite (NO(2)) in the supernatant and protein assays were performed in the respective groups at various time intervals. EPR was used to establish the antioxidant effect of RC, FC and TC with respect to superoxide anion (O(2)(.-)), hydroxyl radicals ((. )OH), nitric oxide (NO) radical and peroxynitrite anion (ONOO) generated from pyrogallol, menadione, DETA-NO and Sin-1 respectively. RT-PCR was performed for the three groups for GCLC, iNOS, Cu-Zn SOD and GAPDH gene expression. RESULTS: All the three herbs were effective in elevating the GSH levels, expression of the gamma-glutamylcysteine ligase and Cu-Zn SOD genes. The herbs also exhibited strong free radical scavenging properties against reactive oxygen and nitrogen species as studied by electron paramagnetic resonance spectroscopy. In addition all the three herbs significantly diminished the expression of iNOS gene after 48 hours which plays a major role in neuronal injury during hypoxia/ischemia. CONCLUSIONS: RC, FC and TC therefore attenuate oxidative stress mediated cell injury during OGD and exert the above effects at both the cytosolic as well as at gene expression level and may be an effective therapeutic tool against ischemic brain damage