3,662 research outputs found
Guidelines for pre-clinical assessment of the acetylcholine receptor-specific passive transfer myasthenia gravis model - recommendations for methods and experimental designs.
Antibodies against the muscle acetylcholine receptor (AChR) are the most common cause of myasthenia gravis (MG). Passive transfer of AChR antibodies from MG patients into animals reproduces key features of human disease, including antigenic modulation of the AChR, complement-mediated damage of the neuromuscular junction, and muscle weakness. Similarly, AChR antibodies generated by active immunization in experimental autoimmune MG models can subsequently be passively transferred to other animals and induce weakness. The passive transfer model is useful to test therapeutic strategies aimed at the effector mechanism of the autoantibodies. Here we summarize published and unpublished experience using the AChR passive transfer MG model in mice, rats and rhesus monkeys, and give recommendations for the design of preclinical studies in order to facilitate translation of positive and negative results to improve MG therapies
Soft-x-ray interferometer for single-shot laser linewidth measurements
Includes bibliographical references (page 957).A soft-x-ray Mach-Zehnder interferometer configuration that makes use of the time delay introduced by diffraction gratings to conduct single-shot measurements of the linewidth of soft-x-ray laser amplifiers is proposed and analyzed. The scheme was experimentally demonstrated in the near-IR region of the spectrum by measurement of the mode separation of a semiconductor laser. A symmetric configuration with compensated time delays that can be implemented for plasma diagnostics and for evaluating soft-x-ray optics is also discussed
Serendipitous discovery of RR Lyrae stars in the Leo V ultra-faint galaxy
During the analysis of RR Lyrae stars discovered in the High cadence
Transient Survey (HiTS) taken with the Dark Energy Camera at the 4-m telescope
at Cerro Tololo Inter-American Observatory, we found a group of three very
distant, fundamental mode pulsator RR Lyrae (type ab). The location of these
stars agrees with them belonging to the Leo V ultra-faint satellite galaxy, for
which no variable stars have been reported to date. The heliocentric distance
derived for Leo V based on these stars is 173 +/- 5 kpc. The pulsational
properties (amplitudes and periods) of these stars locate them within the locus
of the Oosterhoff II group, similar to most other ultra-faint galaxies with
known RR Lyrae stars. This serendipitous discovery shows that distant RR Lyrae
stars may be used to search for unknown faint stellar systems in the outskirts
of the Milky Way.Comment: Accepted in ApJ Letter
Identification of viral infections in the prostate and evaluation of their association with cancer
<p>Abstract</p> <p>Background</p> <p>Several viruses with known oncogenic potential infect prostate tissue, among these are the polyomaviruses BKV, JCV, and SV40; human papillomaviruses (HPVs), and human cytomegalovirus (HCMV) infections. Recently, the Xenotropic Murine Leukemia Virus-related gammaretrovirus (XMRV) was identified in prostate tissue with a high prevalence observed in prostate cancer (PC) patients homozygous for the glutamine variant of the RNASEL protein (462Q/Q). Association studies with the R462Q allele and non-XMRV viruses have not been reported. We assessed associations between prostate cancer, prostate viral infections, and the RNASEL 462Q allele in Mexican cancer patients and controls.</p> <p>Methods</p> <p>130 subjects (55 prostate cancer cases and 75 controls) were enrolled in the study. DNA and RNA isolated from prostate tissues were screened for the presence of viral genomes. Genotyping of the RNASEL R462Q variant was performed by Taqman method.</p> <p>Results</p> <p>R/R, R/Q, and Q/Q frequencies for R462Q were 0.62, 0.38, and 0.0 for PC cases and 0.69, 0.24, and 0.07 for controls, respectively. HPV sequences were detected in 11 (20.0%) cases and 4 (5.3%) controls. XMRV and HCMV infections were detected in one and six control samples, respectively. The risk of PC was significantly increased (Odds Ratio = 3.98; 95% CI: 1.17-13.56, p = 0.027) by infection of the prostatic tissue with HPV. BKV, JCV, and SV40 sequences were not detected in any of the tissue samples examined.</p> <p>Conclusions</p> <p>We report a positive association between PC and HPV infection. The 462Q/Q RNASEL genotype was not represented in our PC cases; thus, its interaction with prostate viral infections and cancer could not be evaluated.</p
Anatomy and histochemistry of leaves, stem and xylopodium of Gomphrena perennis L.
Gomphrena perennis L. es una hierba perenne nativa,distribuida en el norte y centro de Argentina,a la cual se le atribuyen propiedades emolientes,diuréticas, depurativas, estomacales, febrífugas, antirreumáticasy antidiarreicas. Nuestro objetivo fueestudiar la anatomía de hoja, tallo y xilopodio deG. perennis y realizar pruebas histoquímicas paradetectar sustancias ergásticas, para lo cual se recolectaronplantas en las cimas y laderas de Sierra deLos Padres y La Vigilancia, pcia. de Buenos Aires.Se diafanizaron hojas mediante la técnica de clarificación5-5-5, para caracterizar su epidermis. Serealizaron cortes transversales (C.T.) de materialfresco de los órganos y se tiñó con colorantes ortocromáticosy metacromáticos para observar la disposición de los tejidos. Además, se realizaron pruebashistoquímicas para determinar almidón, aceites,taninos y mucílagos. En la hoja, el diafanizadomostró una disposición estomática de tipo anomocítica,y el C.T. una anatomía tipo Kranz y drusasentre los haces vasculares. Además, se observarontricomas epidérmicos no glandulares. En el tallo seobservó colénquima angular subepidérmico, un crecimientosecundario anómalo, drusas, y se evidenciócontenido de almidón. Si bien los análisis histoquímicospreliminares no demostraron la presenciade aceites, mucílagos y taninos, se continuarácon los estudios para identificar posibles principiosactivos presentes en plantas que crecen en las sierrasde Buenos Aires.Fil: Acuña, A. L. A.. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; ArgentinaFil: Thevenon, Mario. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; ArgentinaFil: Martinez Tosto, Ana Cecilia. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones en Sanidad Producción y Ambiente. - Comisión de Investigaciones Científicas de la Provincia de Buenos Aires. Instituto de Investigaciones en Sanidad Producción y Ambiente; ArgentinaFil: Fernández Honaine, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Cardinali, Francisco José. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones en Sanidad Producción y Ambiente. - Comisión de Investigaciones Científicas de la Provincia de Buenos Aires. Instituto de Investigaciones en Sanidad Producción y Ambiente; ArgentinaXXXVIII Jornadas Argentinas de BotánicaEntre RíosArgentinaSociedad Argentina de Botánic
Shale disposal of U.S. high-level radioactive waste.
Approved for public release; further dissemination unlimited. Issued by Sandia National Laboratories, operated for the United States Department of Energy by Sandia Corporation. NOTICE: Neither the United States Government, nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors, or their employees, make any warranty, express or implied, or assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represent that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government, any agency thereof, or any of their contractors or subcontractors. The views and opinions expressed herein do not necessarily state or reflect those of the United States Government, any agency thereof, or any of their contractors. Printed in the United States of America. This report has been reproduced directly from the best available copy
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