RESUMEN
Studies reporting tick infection rates for Powassan virus (POWV), an emerging zoonotic arthropod-borne pathogen responsible for POWV disease in the Commonwealth of Pennsylvania, are limited. To determine the presence and ascertain a statewide prevalence of POWV, ticks were collected from 9,912 hunter-harvested white-tailed deer (Odocoileus virginianus) heads presented to six regional Pennsylvania Game Commission Chronic Wasting Disease sampling stations in early December of 2013, 2014 and 2015. Of the 2,973 ticks recovered, 1,990 (66.9%) were identified as adult Ixodes scapularis (black-legged tick). The 1,990 I. scapularis ticks were PCR-tested for the presence of POWV. The ticks had a statewide Powassan/deer tick virus infection rate of 0.05%, providing evidence of this pathogen in Pennsylvania's adult I. scapularis ticks and supporting the need for more comprehensive pathogen prevalence assessment strategies, as well as increased public health awareness for this emerging zoonotic arthropod-borne pathogen of public health concern.
Asunto(s)
Ciervos/parasitología , Virus de la Encefalitis Transmitidos por Garrapatas/aislamiento & purificación , Ixodes/virología , Salud Pública , Zoonosis , Animales , Pennsylvania/epidemiología , ARN Viral/genética , ARN Viral/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/parasitologíaRESUMEN
The ontogeny of ligand binding to N-methyl-D-aspartate (NMDA), alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and kainate (KA) receptors and to the high affinity, sodium-dependent D-aspartate binding site in prenatal and postnatal ovine brains was studied using quantitative in vitro autoradiography. In general, the binding density for each of the excitatory amino acid receptors peaked during late prenatal and early postnatal development. In contrast, binding density for D-aspartate remained low during late prenatal and early postnatal development and peaked in the adult. These data suggest that an excess number of excitatory amino acid receptors and/or a relative deficiency of transporters may make the immature brain more vulnerable to the pathologic effects of glutamate and other related excitatory amino acids.
Asunto(s)
Envejecimiento/metabolismo , Animales Recién Nacidos/metabolismo , Ácido Aspártico/metabolismo , Encéfalo/embriología , Encéfalo/metabolismo , Receptores de Glutamato/metabolismo , Animales , Animales Recién Nacidos/crecimiento & desarrollo , Autorradiografía , Sitios de Unión , Desarrollo Embrionario y Fetal/fisiología , Feto/metabolismo , Feto/fisiología , Ácido Glutámico/metabolismo , Ácido Kaínico/metabolismo , N-Metilaspartato/metabolismo , Ovinos/embriología , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico/metabolismoRESUMEN
Three denaturing techniques have been evaluated for their ability to induce irreversible aggregation and precipitation of recombinant porcine growth hormone (pGH). The denaturing stimuli included thermal denaturation, interfacial denaturation through the introduction of a high air/water interface by vortex agitation, and a guanidine (Gdn) HCl technique which involved rapid dilution of a partially unfolded state of pGH to nondenaturing conditions. Soluble and insoluble pGH fractions were evaluated for the presence of covalently modified species and soluble aggregates by size exclusion chromatography (SEC), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and isoelectric focusing (IEF). In each of the three denaturation methods, precipitation was found to be irreversible, as the precipitated pellet could not be solubilized upon resuspending in buffer. The soluble pGH fractions consisted of only monomeric material and the insoluble protein pellet could be completely solubilized with Gdn HCl or SDS. There was no evidence of detectable covalent modifications in the precipitated protein pellet following any of the three denaturation techniques. Three excipients, Tween 20, hydroxypropyl-beta-cyclodextrin (HPCD), and sorbitol were evaluated for their stabilizing ability using each of the three denaturation methods and the degree of stabilization was found to be dependent upon the denaturing stimulus incorporated. Tween 20 was found to be highly effective in preventing pGH precipitation using the interfacial and Gdn techniques and was moderately effective using the thermal denaturation method. Inclusion of HPCD in the sample buffer significantly reduced precipitation using the thermal and interfacial methods but was ineffective in the Gdn technique.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Excipientes/farmacología , Hormona del Crecimiento/química , Animales , Tampones (Química) , Celulosa/análogos & derivados , Cromatografía en Gel , Electroforesis en Gel de Poliacrilamida , Hormona del Crecimiento/efectos de los fármacos , Guanidinas/química , Calor , Focalización Isoeléctrica , Polisorbatos , Desnaturalización Proteica , Solubilidad , Soluciones , Sorbitol , Espectrofotometría Ultravioleta , Porcinos , TemperaturaRESUMEN
Neuroblastomas are malignant childhood neoplasms that arise from derivatives of the neural crest. We report the characterization of a new neuroblastoma cell line, designated NBL-W, derived from the primary tumor of a patient with stage IVS disease (S. L. Cohn, C. V. Herst, H. S. Maurer, and S. T. Rosen, J. Clin. Oncol., 5: 1441-1444, 1987) according to the criteria of Evans [A. E. Evans, G. J. D'Angio, and J. Randolf, Cancer (Phila.), 27: 374-378, 1971]. Neurite-bearing (N) and substrate-adherent (S) cell lines have been subcloned from the parent line. N and S cells can interconvert, and both cell types label with the neural crest cell surface marker antibody, HNK-1. Cells in the subcloned lines and in the parent line have been shown by Southern blot analysis to contain approximately 100 copies of the N-myc gene. Cytogenetic analysis shows a homogeneously staining region present on chromosome 19. Although these subclones are of identical genotype, the S cells express lower amounts of N-myc mRNA and protein as compared to the N cells. N cells express several neuronal proteins including the neurotransmitter-processing enzymes tyrosine hydroxylase and dopamine beta-hydroxylase, the neuronal intermediate filament proteins peripherin and NF66/alpha-internexin, and the neural cell adhesion molecule. S cells generally lack neuronal markers but express the mesenchymal intermediate filament protein vimentin, and a small subset of the S cells express glial fibrillary acidic protein. Some S cells were labeled weakly with neural cell adhesion molecule antibody; others were negative. S cells did not express the glial marker S-100 or a melanocyte marker, tyrosinase. Thus, S cells express the neural crest marker HNK-1 but do not express a set of antigens characteristic of any known cell type derived from the neural crest. These results are consistent with the suggestion that differential N-myc expression may be involved in the interconversion of N and S cells but indicate that the S cell phenotype need not represent a highly differentiated neural crest derivative.