176 research outputs found
Neuron-Derived Neurotrophic Factor Is Mutated in Congenital Hypogonadotropic Hypogonadism
Congenital hypogonadotropic hypogonadism (CHH) is a rare genetic disorder characterized by infertility and the absence of puberty. Defects in GnRH neuron migration or altered GnRH secretion and/or action lead to a severe gonadotropin-releasing hormone (GnRH) deficiency. Given the close developmental association of GnRH neurons with the olfactory primary axons, CHH is often associated with anosmia or hyposmia, in which case it is defined as Kallmann syndrome (KS). The genetics of CHH are heterogeneous, and >40 genes are involved either alone or in combination. Several CHH-related genes controlling GnRH ontogeny encode proteins containing fibronectin-3 (FN3) domains, which are important for brain and neural development. Therefore, we hypothesized that defects in other FN3-superfamily genes would underlie CHH. Next-generation sequencing was performed for 240 CHH unrelated probands and filtered for rare, protein-truncating variants (PTVs) in FN3-superfamily genes. Compared to gnomAD controls the CHH cohort was statistically enriched for PTVs in neuron-derived neurotrophic factor (NDNF) (p = 1.40 x 10(-6)). Three heterozygous PTVs (p.Lys62*, p.Tyr128Thrfs*55, and p.Trp469*, all absent from the gnomAD database) and an additional heterozygous missense mutation (p.Thr201Ser) were found in four KS probands. Notably, NDNF is expressed along the GnRH neuron migratory route in both mouse embryos and human fetuses and enhances GnRH neuron migration. Further, knock down of the zebrafish ortholog of NDNF resulted in altered GnRH migration. Finally, mice lacking Ndnf showed delayed GnRH neuron migration and altered olfactory axonal projections to the olfactory bulb; both results are consistent with a role of NDNF in GnRH neuron development. Altogether, our results highlight NDNF as a gene involved in the GnRH neuron migration implicated in KS.Peer reviewe
Safety and Efficacy of Digital Single-Operator Pancreatoscopy for Obstructing Pancreatic Ductal Stones
Planetary bearing defect detection in a commercial helicopter main gearbox with vibration and acoustic emission
The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Helicopter gearboxes significantly differ from other transmission types and exhibit unique behaviors that reduce the effectiveness of traditional fault diagnostics methods. In addition, due to lack of redundancy, helicopter transmission failure can lead to catastrophic accidents. Bearing faults in helicopter gearboxes are difficult to discriminate due to the low signal to noise ratio (SNR) in the presence of gear vibration. In addition, the vibration response from the planet gear bearings must be transmitted via a time-varying path through the ring gear to externally mounted accelerometers, which cause yet further bearing vibration signal suppression. This research programme has resulted in the successful proof of concept of a broadband wireless transmission sensor that incorporates power scavenging whilst operating within a helicopter gearbox. In addition, this paper investigates the application of signal separation techniques in detection of bearing faults within the epicyclic module of a large helicopter (CS-29) main gearbox using vibration and Acoustic Emissions (AE). It compares their effectiveness for various operating conditions. Three signal processing techniques including an adaptive filter, spectral kurtosis and envelope analysis, were combined for this investigation. In addition, this research discusses the feasibility of using AE for helicopter gearbox monitoring
The Lantern, 2018-2019
The Treasure Buried in Ponce de Leon\u27s Fountain of Youth Archaeological Park • High Cards on the Low River • Sestina of a Vagina left in the microwave too long • Keeps on Tripping • The Auction • Nuclear Meltdown on Seedship C5B.6 • Cock Fight • An Interview with God • Minimum Wage • Star-Crossed Lovers • Romeo Echo Alpha • PM Entertainment, or Action Beats • The Gospel of Aggregates • Hel Hath no Fury • Crossing the Line • Mango de la hora • Stress Judgment • Perception (Part 2) • Rain Falling Up • Church: the Italian Market • Landscape with the Fall of Hillary • Forced to Ponder • Morally Upright • Adulthood • Migration in Tandem • Hospital Bed • To Autumn (After Keats) • Selected Tweets • Hidden Moments • Mysteries are Wrong • Jukebox Memory • Flames • A Simple Moment • The Farmhouse • Lord, Let Me Catch a Fish • Sun-Kissed • Five • The Thing • The Moons of Mars • You are Weak • You Kept Me Quiet • Offer Her a Seat • Sacraments • Cigar • The Lake George Mafia • Houses • Spun Out • To Romanticize the Restless • 12/25/17 • skylight • lanternflies • Goo Girls • Toi Le • Lovers, Thinkers, Rebels • home in paradise • Irreverence • The Fisherman • St Mary Episcopal Cathedral, Edinburgh • Mirror 2https://digitalcommons.ursinus.edu/lantern/1187/thumbnail.jp
The Lantern, 2017-2018
On Dissociation • Untouchable • After Rocket Man • The Science Fair • Cardinal Rule at Stephen J. Memorial • Quentin & Sylvie • Cabello • The Get Out • Painting Day • Black, White and Grey • Family Pruning • How to Remove a Stain • Becoming Ourselves • Wonderbread U • Overture • Pescadero • Gross • Stage Fright • Lucky Daddy • Sarah • Rumble • Silvermine • The Green Iguana • A Poem for Ghost Children • A Poem for Lost Boys • Mother • Drop of Grease • Don\u27t Wanna be White • I • Amelia Earhart Disappeared Into My Vagina: An Ode to Cunts, Menstrual Cups and All Things Woman • Suburban Summer • Nightmares and Dreams Induced by My Mother • Teacups, Skins, etc. • Three Thoughts About My Bedroom • Dear Siri • 2 Queens (Beyonce in Reference to Sonia Sanchez) • Voyeurs • In Front of the Bathroom Mirror • To a Rose • Howl • Mice • Mirror • Language Accordion Volcano Mouth • Lucky Woman • Butterscotch • To Persephone • Wolf • Notes Never Passed • Topple • Bust • Kyoto • Identity • Sunflower • Tornabuoni Bubbles • Olympia • Decayed Hall • Perspectivehttps://digitalcommons.ursinus.edu/lantern/1186/thumbnail.jp
A Soluble Form of the High Affinity IgE Receptor, Fc-Epsilon-RI, Circulates in Human Serum
Soluble IgE receptors are potential in vivo modulators of
IgE-mediated immune responses and are thus important for our basic understanding
of allergic responses. We here characterize a novel soluble version of the
IgE-binding alpha-chain of Fc-epsilon-RI (sFcεRI), the high affinity
receptor for IgE. sFcεRI immunoprecipitates as a protein of ∼40 kDa and
contains an intact IgE-binding site. In human serum, sFcεRI is found as a
soluble free IgE receptor as well as a complex with IgE. Using a newly
established ELISA, we show that serum sFcεRI levels correlate with serum IgE
in patients with elevated IgE. We also show that serum of individuals with
normal IgE levels can be found to contain high levels of sFcεRI. After
IgE-antigen-mediated crosslinking of surface FcεRI, we detect sFcεRI in
the exosome-depleted, soluble fraction of cell culture supernatants. We further
show that sFcεRI can block binding of IgE to FcεRI expressed at the cell
surface. In summary, we here describe the alpha-chain of FcεRI as a
circulating soluble IgE receptor isoform in human serum
Revisiting the Myths of Protein Interior: Studying Proteins with Mass-Fractal Hydrophobicity-Fractal and Polarizability-Fractal Dimensions
A robust marker to describe mass, hydrophobicity and polarizability distribution holds the key to deciphering structural and folding constraints within proteins. Since each of these distributions is inhomogeneous in nature, the construct should be sensitive in describing the patterns therein. We show, for the first time, that the hydrophobicity and polarizability distributions in protein interior follow fractal scaling. It is found that (barring ‘all-α’) all the major structural classes of proteins have an amount of unused hydrophobicity left in them. This amount of untapped hydrophobicity is observed to be greater in thermophilic proteins, than that in their (structurally aligned) mesophilic counterparts. ‘All-β’(thermophilic, mesophilic alike) proteins are found to have maximum amount of unused hydrophobicity, while ‘all-α’ proteins have been found to have minimum polarizability. A non-trivial dependency is observed between dielectric constant and hydrophobicity distributions within (α+β) and ‘all-α’ proteins, whereas absolutely no dependency is found between them in the ‘all-β’ class. This study proves that proteins are not as optimally packed as they are supposed to be. It is also proved that origin of α-helices are possibly not hydrophobic but electrostatic; whereas β-sheets are predominantly hydrophobic in nature. Significance of this study lies in protein engineering studies; because it quantifies the extent of packing that ensures protein functionality. It shows that myths regarding protein interior organization might obfuscate our knowledge of actual reality. However, if the later is studied with a robust marker of strong mathematical basis, unknown correlations can still be unearthed; which help us to understand the nature of hydrophobicity, causality behind protein folding, and the importance of anisotropic electrostatics in stabilizing a highly complex structure named ‘proteins’
Investigations into a putative role for the novel BRASSIKIN pseudokinases in compatible pollen-stigma interactions in Arabidopsis thaliana.
BACKGROUND: In the Brassicaceae, the early stages of compatible pollen-stigma interactions are tightly controlled with early checkpoints regulating pollen adhesion, hydration and germination, and pollen tube entry into the stigmatic surface. However, the early signalling events in the stigma which trigger these compatible interactions remain unknown. RESULTS: A set of stigma-expressed pseudokinase genes, termed BRASSIKINs (BKNs), were identified and found to be present in only core Brassicaceae genomes. In Arabidopsis thaliana Col-0, BKN1 displayed stigma-specific expression while the BKN2 gene was expressed in other tissues as well. CRISPR deletion mutations were generated for the two tandemly linked BKNs, and very mild hydration defects were observed for wild-type Col-0 pollen when placed on the bkn1/2 mutant stigmas. In further analyses, the predominant transcript for the stigma-specific BKN1 was found to have a premature stop codon in the Col-0 ecotype, but a survey of the 1001 Arabidopsis genomes uncovered three ecotypes that encoded a full-length BKN1 protein. Furthermore, phylogenetic analyses identified intact BKN1 orthologues in the closely related outcrossing Arabidopsis species, A. lyrata and A. halleri. Finally, the BKN pseudokinases were found to be plasma-membrane localized through the dual lipid modification of myristoylation and palmitoylation, and this localization would be consistent with a role in signaling complexes. CONCLUSION: In this study, we have characterized the novel Brassicaceae-specific family of BKN pseudokinase genes, and examined the function of BKN1 and BKN2 in the context of pollen-stigma interactions in A. thaliana Col-0. Additionally, premature stop codons were identified in the predicted stigma specific BKN1 gene in a number of the 1001 A. thaliana ecotype genomes, and this was in contrast to the out-crossing Arabidopsis species which carried intact copies of BKN1. Thus, understanding the function of BKN1 in other Brassicaceae species will be a key direction for future studies
Evidence of Compromised Blood-Spinal Cord Barrier in Early and Late Symptomatic SOD1 Mice Modeling ALS
Background: The blood-brain barrier (BBB), blood-spinal cord barrier (BSCB), and blood-cerebrospinal fluid barrier (BCSFB) control cerebral/spinal cord homeostasis by selective transport of molecules and cells from the systemic compartment. In the spinal cord and brain of both ALS patients and animal models, infiltration of T-cell lymphocytes, monocyte-derived macrophages and dendritic cells, and IgG deposits have been observed that may have a critical role in motor neuron damage. Additionally, increased levels of albumin and IgG have been found in the cerebrospinal fluid in ALS patients. These findings suggest altered barrier permeability in ALS. Recently, we showed disruption of the BBB and BSCB in areas of motor neuron degeneration in the brain and spinal cord in G93A SOD1 mice modeling ALS at both early and late stages of disease using electron microscopy. Examination of capillary ultrastructure revealed endothelial cell degeneration, which, along with astrocyte alteration, compromised the BBB and BSCB. However, the effect of these alterations upon barrier function in ALS is still unclear. The aim of this study was to determine the functional competence of the BSCB in G93A mice at different stages of disease.
Methodology/Principal Findings: Evans Blue (EB) dye was intravenously injected into ALS mice at early or late stage disease. Vascular leakage and the condition of basement membranes, endothelial cells, and astrocytes were investigated in cervical and lumbar spinal cords using immunohistochemistry. Results showed EB leakage in spinal cord microvessels from all G93A mice, indicating dysfunction in endothelia and basement membranes and confirming our previous ultrastructural findings on BSCB disruption. Additionally, downregulation of Glut-1 and CD146 expressions in the endothelial cells of the BSCB were found which may relate to vascular leakage.
Conclusions/Significance: Results suggest that the BSCB is compromised in areas of motor neuron degeneration in ALS mice at both early and late stages of the disease
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