Indium In-111 pentetreotide scintigraphy: Application to carotid body tumors

AbstractPurpose: This study was conducted to investigate and illustrate the use of Indium In-111 pentetreotide scintigraphy as it applies to carotid body tumors (CBT). Localization has relied primarily on ultrasonography, computed tomography, and magnetic resonance imaging with angiographic confirmation. These methods only assess the cervical bifurcation without providing an evaluation of metastasis in patients without symptoms or recurrence in patients after surgery.Methods: Indium In-111 pentetreotide scintigraphy was used in five patients with a diagnosis of CBT. Four patients were evaluated after surgical excision for evidence of tumor recurrence. One patient was evaluated before excision for diagnostic confirmation.Results: No evidence of tumor recurrence was demonstrated in the four patients who had undergone previous CBT excision. One of these patients had increased activity in the pituitary, later confirmed as an enlarged pituitary without evidence of an adenoma with computed tomography. The diagnosis of CBT was confirmed in the patient evaluated before surgery. This patient also had increased activity in the occipital region, confirmed as the site of previous ischemia on computed tomography.Conclusion: Indium In-111 pentetreotide scintigraphy is a new innovative method for viewing neuroendocrine tumors. Its potential lies not only in tumor localization but also in identification of recurrent tumor at the operative site and metastatic disease. (J Vasc Surg 1997;25:905-8.

RNA-binding proteins hnRNP A2/B1 and CUGBP1 suppress fragile X CGG premutation repeat-induced neurodegeneration in a Drosophila model of FXTAS

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a recently described neurodegenerative disorder of older adult carriers of premutation alleles (60–200 CGG repeats) in the fragile X mental retardation gene (FMR1). It has been proposed that FXTAS is an RNA-mediated neurodegenerative disease caused by the titration of RNA-binding proteins by the CGG repeats. To test this hypothesis, we utilize a transgenic Drosophila model of FXTAS that expresses a premutation-length repeat (90 CGG repeats) from the 5′ UTR of the human FMR1 gene and displays neuronal degeneration. Here, we show that overexpression of RNA-binding proteins hnRNP A2/B1 and CUGBP1 suppresses the phenotype of the CGG transgenic fly. Furthermore, we show that hnRNP A2/B1 directly interacts with riboCGG repeats and that the CUGBP1 protein interacts with the riboCGG repeats via hnRNP A2/B1

Live imaging of stem cell and progeny behaviour in physiological hair-follicle regeneration

Tissue development and regeneration depend on cell-cell interactions and signals that target stem cells and their immediate progeny. However, the cellular behaviours that lead to a properly regenerated tissue are not well understood. Using a new, non-invasive, intravital two-photon imaging approach we study physiological hair-follicle regeneration over time in live mice. By these means we have monitored the behaviour of epithelial stem cells and their progeny during physiological hair regeneration and addressed how the mesenchyme influences their behaviour. Consistent with earlier studies, stem cells are quiescent during the initial stages of hair regeneration, whereas the progeny are more actively dividing. Moreover, stem cell progeny divisions are spatially organized within follicles. In addition to cell divisions, coordinated cell movements of the progeny allow the rapid expansion of the hair follicle. Finally, we show the requirement of the mesenchyme for hair regeneration through targeted cell ablation and long-term tracking of live hair follicles. Thus, we have established an in vivo approach that has led to the direct observation of cellular mechanisms of growth regulation within the hair follicle and that has enabled us to precisely investigate functional requirements of hair-follicle components during the process of physiological regeneration. © 2012 Macmillan Publishers Limited. All rights reserved

LSST Cadence Optimization White Paper in Support of Observations of Unresolved Tidal Stellar Streams in Galaxies beyond the Local Group

Deep observations of faint surface brightness stellar tidal streams in external galaxies with LSST are addressed in this White Paper contribution. We propose using the Wide--Fast--Deep survey that contains several nearby galaxies (at distances where the stars themselves are not resolved, i.e., beyond 20 Mpc). In the context of hierarchical galaxy formation, it is necessary to understand the prevalence and properties of tidal substructure around external galaxies based on integrated (i.e., unresolved) diffuse light. This requires collecting observations on much larger samples of galaxies than the Milky Way and M31. We will compare the observed structures to the predictions of cosmological models of galactic halo formation that inform us about the number and properties of streams around Milky Way-like galaxies. The insight gained from these comparisons will allow us to infer the properties of stream progenitors (masses, dynamics, metallicities, stellar populations). The changes in the host galaxies caused by the interactions with the dissolving companion galaxies will be another focus of our studies. We conclude by discussing synergies with WFIRST and Euclid, and also provide concrete suggestions for how the effects of scattered light could be minimized in LSST images to optimize the search for low surface brightness features, such as faint unresolved stellar tidal streams.Comment: 13 pages, 2 figures, submitted to Call for White Papers on LSST Cadence Optimizatio

Uncovering Biosynthetic Relationships Between Antifungal Nonadrides and Octadrides

Maleidrides are a class of bioactive secondary metabolites unique to filamentous fungi, which contain one or more maleic anhydrides fused to a 7-, 8- or 9- membered carbocycle (named heptadrides, octadrides and nonadrides respectively). Herein structural and biosynthetic studies on the antifungal octadride, zopfiellin, and nonadrides scytalidin, deoxyscytalidin and castaneiolide are described. A combination of genome sequencing, bioinformatic analyses, gene disruptions, biotransformations, isotopic feeding studies, NMR and X-ray crystallography revealed that they share a common biosynthetic pathway, diverging only after the nonadride deoxyscytalidin. 5-Hydroxylation of deoxyscytalidin occurs prior to ring contraction in the zopfiellin pathway of Diffractella curvata. In Scytalidium album, 6-hydroxylation-confirmed as being catalysed by the α-ketoglutarate dependent oxidoreductase ScyL2-converts deoxyscytalidin to scytalidin, in the final step in the scytalidin pathway. Feeding scytalidin to a zopfiellin PKS knockout strain led to the production of the nonadride castaneiolide and two novel ring-open maleidrides. © The Royal Society of Chemistry

The Rapidly Flaring Afterglow of the Very Bright and Energetic GRB 070125

We report on multi-wavelength observations, ranging from the X-ray to radio wave bands, of the IPN-localized gamma-ray burst GRB 070125. Spectroscopic observations reveal the presence of absorption lines due to O I, Si II, and C IV, implying a likely redshift of z = 1.547. The well-sampled light curves, in particular from 0.5 to 4 days after the burst, suggest a jet break at 3.7 days, corresponding to a jet opening angle of ~7.0 degrees, and implying an intrinsic GRB energy in the 1 - 10,000 keV band of around E = (6.3 - 6.9)x 10^(51) erg (based on the fluences measured by the gamma-ray detectors of the IPN network). GRB 070125 is among the brightest afterglows observed to date. The spectral energy distribution implies a host extinction of Av < 0.9 mag. Two rebrightening episodes are observed, one with excellent time coverage, showing an increase in flux of 56% in ~8000 seconds. The evolution of the afterglow light curve is achromatic at all times. Late-time observations of the afterglow do not show evidence for emission from an underlying host galaxy or supernova. Any host galaxy would be subluminous, consistent with current GRB host-galaxy samples. Evidence for strong Mg II absorption features is not found, which is perhaps surprising in view of the relatively high redshift of this burst and the high likelihood for such features along GRB-selected lines of sight.Comment: 50 pages, 9 figures, 5 tables Accepted to the Astrophysical Journa

RHIC physics overview

The results from data taken during the last several years at the Relativistic Heavy-Ion Collider (RHIC) will be reviewed in the paper. Several selected topics that further our understanding of constituent quark scaling, jet quenching and color screening effect of heavy quarkonia in the hot dense medium will be presented. Detector upgrades will further probe the properties of Quark Gluon Plasma. Future measurements with upgraded detectors will be presented. The discovery perspectives from future measurements will also be discussed.Comment: 9 pages, 4 figures, invited review article, published by Frontier of Physics in Chin

Understanding the twist-bend nematic phase: the characterisation of 1-(4-cyanobiphenyl-4'-yloxy)-6-(4-cyanobiphenyl-4'-yl) hexane (CB6OCB) and comparison with CB7CB

Acknowledgements The FFTEM data were obtained at the (Cryo) TEM facility at the Liquid Crystal Institute, Kent State University, supported by the Ohio Research Scholars Program Research Cluster on Surfaces in Advanced Materials. ODL acknowledges the support of NSF DMR-1410378 grant. The authors are grateful for financial support from MINECO/FEDER MAT2015-66208-C3-2-P and from the Gobierno Vasco (GI/IT-449-10) OA via RSC Gold4GoldPeer reviewedPublisher PD