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The Tabby cat locus maps to feline chromosome B1.
The Tabby markings of the domestic cat are unique coat patterns for which no causative candidate gene has been inferred from other mammals. In this study, a genome scan was performed on a large pedigree of cats that segregated for Tabby coat markings, specifically for the Abyssinian (Ta-) and blotched (tbtb) phenotypes. There was linkage between the Tabby locus and eight markers on cat chromosome B1. The most significant linkage was between marker FCA700 and Tabby (Z = 7.56, theta = 0.03). Two additional markers in the region supported linkage, although not with significant LOD scores. Pairwise analysis of the markers supported the published genetic map of the cat, although additional meioses are required to refine the region. The linked markers cover a 17-cM region and flank an evolutionary breakpoint, suggesting that the Tabby gene has a homologue on either human chromosome 4 or 8. Alternatively, Tabby could be a unique locus in cats
Future challenges in cephalopod research
We thank AntoÂŽnio M. de Frias Martins, past President of the Unitas Malacologica and Peter Marko, President of the American Malacological Society for organizing the 2013 World Congress of Malacology, and the Cephalopod International Advisory Committee for endorsing a symposium held in honour of Malcolm R. Clarke. In particular, we would like to thank the many professional staff from the University of the Azores for their hospitality, organization, troubleshooting and warm welcome to the Azores. We also thank Malcolm Clarkeâs widow, Dorothy, his daughter Zoeš, JoseÂŽ N. Gomes-Pereira and numerous colleagues and friends of Malcolmâs from around the world for joining us at Ponta Delgada. We are grateful to Lyndsey Claro (Princeton University Press) for granting copyright permissions.Peer reviewedPublisher PD
Hedgehog pathway responsiveness correlates with the presence of primary cilia on prostate stromal cells
<p>Abstract</p> <p>Background</p> <p>Hedgehog (Hh) signaling from the urogenital sinus (UGS) epithelium to the surrounding mesenchyme plays a critical role in regulating ductal formation and growth during prostate development. The primary cilium, a feature of most interphase vertebrate cell types, serves as a required localization domain for Hh signaling transducing proteins.</p> <p>Results</p> <p>Immunostaining revealed the presence of primary cilia in mesenchymal cells of the developing prostate. Cell-based assays of a urongenital sinus mesenchymal cell line (UGSM-2) revealed that proliferation-limiting (serum starvation and/or confluence) growth conditions promoted cilia formation and correlated with pathway activation associated with accumulation of Smoothened in primary cilia. The prostate cancer cell lines PC-3, LNCaP, and 22RV1, previously shown to lack demonstrable autocrine Hh signaling capacity, did not exhibit primary cilia even under proliferation-limiting growth conditions.</p> <p>Conclusion</p> <p>We conclude that paracrine Hedgehog signaling activity in the prostate is associated with the presence of primary cilia on stromal cells but that a role in autocrine Hh signaling remains speculative.</p
Characteristics of survivors: growth and nutritional condition of early stages of the hake species Merluccius paradoxus and M. capensis in the southern Benguela ecosystem
Larval mortality in marine fish is strongly linked to characteristic traits such as growth and condition, but the variability in these traits is poorly understood. We tried to identify the variability in growth in relation to conditions leading to greater survival chances for early stages of Cape hake, Merluccius paradoxus and M. capensis, in the Benguela upwelling ecosystem. During two cruises in 2007 and one cruise in 2008, hake larvae and juveniles were caught. Otolith microstructures revealed a larval age ranging from 2 to 29 days post-hatching (dph), whereas juvenile age was 67â152 dph. RNA:DNA ratios, used to evaluate nutritional condition, were above the relevant threshold level for growth. No strong coupling between growth and condition was detected, indicating a complex relationship between these factors in the southern Benguela ecosystem. Merluccius paradoxus juveniles caught in 2007 (the surviving larvae of 2006) had significantly higher larval growth rates than larvae hatched in 2007 and 2008, possibly indicating selection for fast growth in 2006. High selection pressure on growth could be linked to predation avoidance, including cannibalism
Evidence for the formation of magnetic moments in the cuprate superconductor HgCuBaCaCuO below seen by NQR
We report pure zero field nuclear magnetic resonance (NQR) measurements on
the optimally doped three layer high--compounds HgBaCaCuO and
HgBaCaCuO(F) with 134 K. Above two Cu NQR line pairs are
observed in the spectra corresponding to the two inequivalent Cu lattice sites.
Below the Cu NQR spectra show additional lines leading to the extreme
broadened Cu NQR spectra at 4.2 K well known for the HgBaCaCuO compounds. The
spin-lattice relaxation curves follow a triple exponential function with
coefficients depend onto the saturation time (number of saturation pulses),
whereas the spin-spin relaxation curve is described by a single exponential
function. From the spin-lattice relaxation we deduced a complete removal of the
Kramers degeneracy of the Cu quadrupole indicating that the additional lines
are due to a Zeemann splitting of the Cu lines due to the spontaneous
formation of magnetic moments within the CuO layers. Below 140 K, the spectra
are well fitted by a number of 6 Cu line pairs. From the number of
the Cu lines, the position of the lines relative to each other and the complete
removal of the Kramers degeneracy we deduced an orientation of the magnetic
moments parallel to the symmetry axis of the electric field gradient tensor
with magnitudes of the order of 1000 G. We also discuss the possible
microscopic origin of the observed internal magnetic fields.Comment: 11 pages, 12 figure
Application of Hanschâs Model to Capsaicinoids and Capsinoids: A Study Using the Quantitative StructureâActivity Relationship. A Novel Method for the Synthesis of Capsinoids
We describe a synthetic approach for two families of compounds, the capsaicinoids and capsinoids,
as part of a study of the quantitative relationship between structure and activity
Simple Model of the Transduction of Cell-Penetrating Peptides
Cell-penetrating peptides (CPPs) such as HIV's trans-activating
transcriptional activator (TAT) and polyarginine rapidly pass through the
plasma membranes of mammalian cells by an unknown mechanism called
transduction. They may be medically useful when fused to well-chosen chains of
fewer than about 35 amino acids. I offer a simple model of transduction in
which phosphatidylserines and CPPs effectively form two plates of a capacitor
with a voltage sufficient to cause the formation of transient pores
(electroporation). The model is consistent with experimental data on the
transduction of oligoarginine into mouse C2-C12 myoblasts and makes three
testable predictions.Comment: Seven pages. For a more complete version including the effects of
counterions, see arXiv:0810.2358v3 [q-bio.BM
Direct characterization of gas adsorption and phase transition of a metal organic framework using in-situ Raman spectroscopy
Adsorbents are widely used in gas separation and storage processes. Performance improvements are largely achieved through the continual development of new materials with unique sorption properties. Adsorption characterization techniques, therefore, play a central role in material research and development. Here, in-situ Raman spectroscopy is presented as a multi-purpose laboratory tool for analyzing adsorption performance. In contrast to conventional laboratory techniques requiring macroscopic samples, adsorption analysis via Raman spectroscopy can be performed on samples of less than 1 mg. Furthermore, simultaneous Raman multi-phase measurements of the adsorbent structure as well as the free and bound adsorbate, are shown to provide molecular insights into the operation of functional adsorbents at conditions representative of industrial applications, which are often not attainable in conventional crystallography. Firstly, a Raman-based method is demonstrated for directly quantifying absolute adsorption capacity within individual particles. The technique is validated for Raman measurements of carbon dioxide on silica gel and compared to gravimetric and volumetric analyses. Secondly, Raman spectroscopy is applied to study a novel functional material, ZIF-7, and directly probe its pressure-regulated gate-opening mechanism, which was only observed through indirect means. These Raman measurements confirm that the sharp increase in capacity corresponds to a structural transition in the material and reveal that multiple adsorption sites contribute to the overall capacity. The Raman methods presented here can be applied to a wide range of adsorbent-adsorbate systems and present a basis for further studies into the kinetics of sorption processes
Evolutionary Multi-Objective Design of SARS-CoV-2 Protease Inhibitor Candidates
Computational drug design based on artificial intelligence is an emerging
research area. At the time of writing this paper, the world suffers from an
outbreak of the coronavirus SARS-CoV-2. A promising way to stop the virus
replication is via protease inhibition. We propose an evolutionary
multi-objective algorithm (EMOA) to design potential protease inhibitors for
SARS-CoV-2's main protease. Based on the SELFIES representation the EMOA
maximizes the binding of candidate ligands to the protein using the docking
tool QuickVina 2, while at the same time taking into account further objectives
like drug-likeliness or the fulfillment of filter constraints. The experimental
part analyzes the evolutionary process and discusses the inhibitor candidates.Comment: 15 pages, 7 figures, submitted to PPSN 202
Molecular dynamics and physical stability of amorphous nimesulide drug and its binary drug-polymer systems
yesIn this paper we study the effectiveness of three well known polymers: inulin, Soluplus and PVP in stabilizing amorphous form of nimesulide (NMS) drug. The re-crystallization tendency of pure drug as well as measured drug-polymer systems were examined at isothermal conditions by using broadband dielectric spectroscopy (BDS), and at non-isothermal conditions by differential scanning calorimetry (DSC). Our investigation has shown that the crystallization half-life time of pure NMS at 328 K is equal to 33 minutes. We found that this time can be prolonged to 40 years after adding to NMS 20% of PVP polymer. This polymer proved to be the best NMSâs stabilizer, while the worst stabilization effect was found after adding the inulin to NMS. Additionally, our DSC, BDS and FTIR studies indicate that for suppression of NMSâs re-crystallization in NMS-PVP system, the two mechanisms are responsible: the polymeric steric hindrances as well as the antiplastization effect excerted by the excipient.The authors J.K., Z.W., K.G. and M.P., are grateful for the financial support received within the Project No. 2015/16/W/NZ7/00404 (SYMFONIA 3) from the National Science Centre, Poland. H.M. and L.T. are supported by Science Foundation Ireland under grant No. 12/RC/2275 (Synthesis and Solid State Pharmaceuticals Centre)
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