Metal accumulation in the tissues and shells of the Rapanine Whelk Indothais gradata along an acidified estuarine gradient

Human ImpactsPoster presentation: P-74Acidification of estuaries results from microbial CO2 generation, acid sulphate groundwater discharge, and anthropogenic activities, in the context of weak buffering potential of hyposaline waters. The resulting acidification introduces an additional yet poorly studied factor influencing the ecology and distributions of biological populations and species. Furthermore, it has a complex influence on estuarine chemistry, including altering the speciation of metals and potentially their availability to the biotic component. With the aim of providing baseline information for metal accumulation in the shells and tissues of organisms inhabiting acidified turbid tropical Asian estuaries, we studied the rapanine whelk Indothais gradata from the mineral-acidified Sungai ...postprin

Patients with migraine with aura have increased flow mediated dilation

<p>Abstract</p> <p>Background</p> <p>Endothelium-derived nitric oxide (NO) mediates the arterial dilation following a flow increase (i.e. flow-mediated dilation, FMD), easily assessed in the brachial artery. NO is also involved in cerebral hemodynamics and it is supposed to trigger vascular changes occurring during migraine. This study aimed at investigating whether migraine patients present an altered response to NO also in the peripheral artery system.</p> <p>Methods</p> <p>We enrolled 21 migraineurs (10 with aura [MwA], 11 without aura [MwoA]), and 13 controls. FMD was evaluated with ultrasound in all subjects by measuring the percentage increase of the brachial artery diameter induced by hyperaemia reactive to sustained cuff inflation around the arm above systolic pressure. FMD values were then normalized for shear stress.</p> <p>Results</p> <p>Normalized FMD values were higher in patients with MwA (28.5 10^-2%.s) than in controls (9.0 10^-2%.s) and patients with MwoA (13.7 10^-2%.s) (p < 0.001). FMD was over the median value (19%) in 23.1% of controls, in 45.5% of the MwoA patients, and in 90% of the MwA patients.</p> <p>Conclusions</p> <p>Migraineurs with aura present an excessive arterial response to hyperaemia, likely as an effect of an increased sensitivity to endothelium-derived nitric oxide. This phenomenon observed peripherally might reflect similar characteristics in the cerebral circulation.</p

Development of a New Tacaribe Arenavirus Infection Model and Its Use to Explore Antiviral Activity of a Novel Aristeromycin Analog

Background A growing number of arenaviruses can cause a devastating viral hemorrhagic fever (VHF) syndrome. They pose a public health threat as emerging viruses and because of their potential use as bioterror agents. All of the highly pathogenic New World arenaviruses (NWA) phylogenetically segregate into clade B and require maximum biosafety containment facilities for their study. Tacaribe virus (TCRV) is a nonpathogenic member of clade B that is closely related to the VHF arenaviruses at the amino acid level. Despite this relatedness, TCRV lacks the ability to antagonize the host interferon (IFN) response, which likely contributes to its inability to cause disease in animals other than newborn mice. Methodology/Principal Findings Here we describe a new mouse model based on TCRV challenge of AG129 IFN-α/β and -γ receptor-deficient mice. Titration of the virus by intraperitoneal (i.p.) challenge of AG129 mice resulted in an LD50 of ∼100 fifty percent cell culture infectious doses. Virus replication was evident in the serum, liver, lung, spleen, and brain 4–8 days after inoculation. MY-24, an aristeromycin derivative active against TCRV in cell culture at 0.9 µM, administered i.p. once daily for 7 days, offered highly significant (P\u3c0.001) protection against mortality in the AG129 mouse TCRV infection model, without appreciably reducing viral burden. In contrast, in a hamster model of arenaviral hemorrhagic fever based on challenge with clade A Pichinde arenavirus, MY-24 did not offer significant protection against mortality. Conclusions/Significance MY-24 is believed to act as an inhibitor of S-adenosyl-L-homocysteine hydrolase, but our findings suggest that it may ameliorate disease by blunting the effects of the host response that play a role in disease pathogenesis. The new AG129 mouse TCRV infection model provides a safe and cost-effective means to conduct early-stage pre-clinical evaluations of candidate antiviral therapies that target clade B arenaviruses

Species-Specific Expansion and Molecular Evolution of the 3-hydroxy-3-methylglutaryl Coenzyme A Reductase (HMGR) Gene Family in Plants

Kazakh dandelion (Taraxacum kok-saghyz, Tk) is a rubber-producing plant currently being investigated as a source of natural rubber for industrial applications. Like many other isoprenoids, rubber is a downstream product of the mevalonate pathway. The 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) enzyme catalyzes the conversion of 3-hydroxy-3-methylglutaryl-CoA to mevalonic acid, a key regulatory step in the MVA pathway. Such regulated steps provide targets for increases in isoprenoid and rubber contents via genetic engineering to increase enzyme activities. In this study, we identify a TkHMGR1 gene that is highly expressed in the roots of Kazakh dandelion, the main tissue where rubber is synthesized and stored. This finding paves the way for further molecular and genetic studies of the TkHMGR1 gene, and its role in rubber biosynthesis in Tk and other rubber-producing plants

Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular "reactive oxygen species" (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference

Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects

섬유아세포 성장인자와 파이브로넥틴 복합 단백질로 처리한 타이태늄의 생물학적 효과: 가토의 경골을 이용한 조직계측학적 분석

파이브로넥틴은 세포외기질에 존재하는 당단백질로 세포의 부착, 이동, 성장 및 분화에 관여하며, 섬유아세포 성장인자는 세포의 증식, 이동 및 분화에 영향을 주는 중요한 성장인자로 알려져 있다. 최근 연구에 의하면 파이브로넥틴은 조골세포의 타이태늄 임플란트 표면으로 이주와 증식 및 골생성을 촉진하며, 섬유아세포 성장인자는 파이브로넥틴에 상승작용을 한다고 보고된 바 있다. 이 실험의 목적은 파이브로넥틴 및 섬유아세포 성장인자의 복합 단백질을 이용하여 타이태늄 임플란트의 골 반응을 알아보는 것이다. 체중 2.5kg 내외의 건강한 18마리의 웅성가토를 준비하여 무균 사육하였고, 순수 타이태늄을 절삭가공하여 직경 3.5mm, 길이 6mm의 machined surface를 지니는 screw type의 임플란트를 준비하였다. 사람의 유전자를 기초로, 유전자 재조합법을 통해, 적절한 primer를 이용하여 얻은 섬유아세포 성장인자를 파이브로넥틴 Ⅲ형 분절의 9-10번 도메인에 결합시켜 얻은 복합 단백질을 준비된 임플란트에 표면처리하여 실험군으로 하였고, 표면처리하지 않은 임플란트를 대조군으로 하여, 가토의 좌우 경골에 각각 2개씩의 임플란트를 식립하였다.This study was supported by the grant from Korea Science and Technology Foundation(KOSEF) through Intellctual Biointerface Engineering Center(IBEC) of Seoul National University