Mesenchymal Stem Cells: Angels or Demons?

Mesenchymal stem cells (MSCs) have been used in cell-based therapy in various disease conditions such as graft-versus-host and heart diseases, osteogenesis imperfecta, and spinal cord injuries, and the results have been encouraging. However, as MSC therapy gains popularity among practitioners and researchers, there have been reports on the adverse effects of MSCs especially in the context of tumour modulation and malignant transformation. These cells have been found to enhance tumour growth and metastasis in some studies and have been related to anticancer-drug resistance in other instances. In addition, various studies have also reported spontaneous malignant transformation of MSCs. The mechanism of the modulatory behaviour and the tumorigenic potential of MSCs, warrant urgent exploration, and the use of MSCs in patients with cancer awaits further evaluation. However, if MSCs truly play a role in tumour modulation, they can also be potential targets of cancer treatment

Extrinsic Factors Involved in the Differentiation of Stem Cells into Insulin-Producing Cells: An Overview

Diabetes mellitus is a chronic disease with many debilitating complications. Treatment of diabetes mellitus mainly revolves around conventional oral hypoglycaemic agents and insulin replacement therapy. Recently, scientists have turned their attention to the generation of insulin-producing cells (IPCs) from stem cells of various sources. To date, many types of stem cells of human and animal origins have been successfully turned into IPCs in vitro and have been shown to exert glucose-lowering effect in vivo. However, scientists are still faced with the challenge of producing a sufficient number of IPCs that can in turn produce sufficient insulin for clinical use. A careful choice of stem cells, methods, and extrinsic factors for induction may all be contributing factors to successful production of functional beta-islet like IPCs. It is also important that the mechanism of differentiation and mechanism by which IPCs correct hyperglycaemia are carefully studied before they are used in human subjects

Viscous Torque and Dissipation in the Inner Region of a Thin Accretion Disk: Implications for Measuring Black Hole Spin

We consider a simple Newtonian model of a steady accretion disk around a black hole. The model is based on height-integrated hydrodynamic equations, alpha-viscosity, and a pseudo-Newtonian potential that results in an innermost stable circular orbit (ISCO) that closely approximates the one predicted by GR. We find that the hydrodynamic models exhibit increasing deviations from the standard disk model of Shakura & Sunyaev as disk thickness H/R or the value of alpha increases. The latter is an analytical model in which the viscous torque is assumed to vanish at the ISCO. We consider the implications of the results for attempts to estimate black hole spin by using the standard disk model to fit continuum spectra of black hole accretion disks. We find that the error in the spin estimate is quite modest so long as H/R < 0.1 and alpha < 0.2. At worst the error in the estimated value of the spin parameter is 0.1 for a non-spinning black hole; the error is much less for a rapidly spinning hole. We also consider the density and disk thickness contrast between the gas in the disk and that inside the ISCO. The contrast needs to be large if black hole spin is to be successfully estimated by fitting the relativistically-broadened X-ray line profile of fluorescent iron emission from reflection off an accretion disk. In our hydrodynamic models, the contrast in density and thickness is low when H/R>0.1, sugesting that the iron line technique may be most reliable in extemely thin disks. We caution that these results have been obtained with a viscous hydrodynamic model and need to be confirmed with MHD simulations of radiatively cooled thin disks.Comment: 32 pages, 10 figures; accepted by Ap

African rainforests: past, present and future

In recent decades, there has been a surge of interest in tropical forests, as there is increased appreciation of the rich biodiversity they host and the many roles they play in the functioning of the Earth system at local, regional and global scales. Of the world’s major tropical forest regions, most research and policy attention has focused on the Amazon region, the world’s largest tropical forest bloc, and to a lesser extent on South East Asia, the third largest tropical forest region. By contrast, the world’s second largest tropical forest region, the tropical forests of Central and West Africa (termed the Guineo-Congolian region) have been relatively neglected. This has been for a number of reasons, including challenging and fragmented politics, civil conflicts and logistical as well as infrastructure challenges. Nevertheless, there is an extensive amount of research activity in the African rainforest zone that has rarely been compiled in a single interdisciplinary volume. This review paper synthesizes the insights emerging from the theme issue on ‘African rainforests: past, present and future’ of Philosophical Transactions of the Royal Society.JRC.H.5-Land Resources Managemen

The past, present and future of Africa's rainforests

The Africanwet tropics contain the second largest area of tropical rainforest in the world (second only toAmazonia), accounting for roughly 30% of global rainforest cover, the lush green heart of an otherwise generally dry continent. These rainforests have global significance and value as reservoirs of biodiversity, as stores and sinks of atmospheric carbon, as regulators of flow of mighty rivers, as sources of moisture to the atmosphere and engines of the global atmospheric circulation, as a key component of the Earth system and its biogeochemical cycles, and as providers of resources and ecosystem services to local communities and the region’s nations. They also have a unique and particular history of changes in climate and human pressure, and face a range of contemporary pressures. Over the twenty-first century, the African rainforest realmhas the potential to witness massive change, both through an expansion of deforestation, hunting and logging, and through the effects of global climate change. This Theme Issue presents a multidisciplinary perspective on the nature and ecology of the African rainforest biome, and examines the current pressures and future threats to this biome. Compared with the other major rainforest regions, Amazonia and Southeast Asia, the African rainforest realm remains understudied, and in particular there have been very few attempts at interdisciplinary synthesis. This Theme Issue is an attempt to address this deficit, and explores what we know about the African rainforests and the threats they face, and what we need to know is this century of rapid change. In some ways, this can be viewed as a complement to similar Theme Issues of this journal focused on the rainforests of Amazonia [1,2] and Southeast Asia [3].JRC.H.5-Land Resources Managemen

58Ni(n,p)58Co and 58Ni(n,2n)57Ni reactions at the neutron energy of 14.54 MeV with covariance analysis

241-245The 58Ni(n,p)58Co and 58Ni(n,2n)57Ni reactions cross sections have been estimated relative to 197Au(n,2n)196Au monitor reaction at the incident neutron energy of 14.54±0.0024 MeV from the D-T fusion nuclear reaction using Purnima neutron generator carried through methods of activation and off-line γ-ray spectrometry. The uncertainty propagation and correlation for measured cross sections have been estimated using covariance analysis through considering the partial uncertainties in different attributes. The present measured reaction cross sections data have been analyzed by comparing with the literature data, with various libraries of evaluated data, like ENDF/B-VIII.0, JEFF-3.3, JENDL/AD-2017, ROSFOND-2010 and TALYS-1.9 theoretical calculations

Effects of Art from the Heart on Nurse Satisfaction and Patient Well-Being

Introduction. Art programs have been shown to positively affect unit culture, quality of care, and nursing practices. Art interventions improve well-being, reduce stress, and enhance nurse-patient communication. Art from the Heart (AFTH) is an art program that provides art supplies, visual art, and patient About Me pages to patients, families and employees at University of Vermont Medical Center (UVMMC).Objective. Assess the efficacy of AFTH through nursing staff perceptions, understanding, and attitudes toward the program.Methods. Structured interviews were conducted on Baird 4, an adult inpatient ward, at UVMMC. A 19-question survey using Likert scales and short answer formats was administered to nursing staff. Questions assessed perceptions of effects of art on patient anxiety and pain, communication, and job satisfaction. Surveys were analyzed to extract major and minor themes.Results. Twenty-eight interviews were obtained and two major themes emerged: nurse satisfaction and patient well-being. Nursing staff satisfaction minor themes included improved productivity, promoting conversation, and creating a positive influence on the unit. Respondents reported that AFTH helped initiate conversations with patients (100% of respondents) and reduced workday stress (68%). The second major theme, patient well-being, included benefits to patients with dementia, providing comfort, and serving as an outlet or distraction. Utilizing AFTH improved perceived patient mood (100%), health (78.5%), and reduced patient anxiety (89.3%).Conclusions. AFTH provides positive benefits by reducing nursing staff stress and perceived patient anxiety; improving communication, perceived patient mood and health; and creating a sense of community. AFTH should be expanded to the entire 6 Community Agency: Burlington City Arts, Art from the Hearthttps://scholarworks.uvm.edu/comphp_gallery/1240/thumbnail.jp

Nkx2-5 and Sarcospan genetically interact in the development of the muscular ventricular septum of the heart

The muscular ventricular septum separates the flow of oxygenated and de-oxygenated blood in air-breathing vertebrates. Defects within it, termed muscular ventricular septal defects (VSDs), are common, yet less is known about how they arise than rarer heart defects. Mutations of the cardiac transcription factor NKX2-5 cause cardiac malformations, including muscular VSDs. We describe here a genetic interaction between Nkx2-5 and Sarcospan (Sspn) that affects the risk of muscular VSD in mice. Sspn encodes a protein in the dystrophin-glycoprotein complex. Sspn knockout (Sspn(KO)) mice do not have heart defects, but Nkx2-5(+/−)/Sspn(KO) mutants have a higher incidence of muscular VSD than Nkx2-5(+/−) mice. Myofibers in the ventricular septum follow a stereotypical pattern that is disrupted around a muscular VSD. Subendocardial myofibers normally run in parallel along the left ventricular outflow tract, but in the Nkx2-5(+/−)/Sspn(KO) mutant they commonly deviate into the septum even in the absence of a muscular VSD. Thus, Nkx2-5 and Sspn act in a pathway that affects the alignment of myofibers during the development of the ventricular septum. The malalignment may be a consequence of a defect in the coalescence of trabeculae into the developing ventricular septum, which has been hypothesized to be the mechanistic basis of muscular VSDs