A highly flexible molecule: The peculiar case of ethynyl isothiocyanate HCCNCS

ABSTRACT A number of the massive clusters in the halo, bulge, and disc of the Galaxy are not genuine globular clusters (GCs) but instead are different beasts altogether. They are the remnant nuclear star clusters (NSCs) of ancient galaxies since accreted by the Milky Way. While some clusters are readily identifiable as NSCs and can be readily traced back to their host galaxy (e.g. M54 and the Sagittarius Dwarf galaxy), others have proven more elusive. Here, we combine a number of independent constraints, focusing on their internal abundances and overall kinematics, to find NSCs accreted by the Galaxy and trace them to their accretion event. We find that the true NSCs accreted by the Galaxy are: M54 from the Sagittarius Dwarf, ω Centari from Gaia-Enceladus/Sausage, NGC 6273 from Kraken, and (potentially) NGC 6934 from the Helmi Streams. These NSCs are prime candidates for searches of intermediate-mass black holes (BHs) within star clusters, given the common occurrence of galaxies hosting both NSCs and central massive BHs. No NSC appears to be associated with Sequoia or other minor accretion events. Other claimed NSCs are shown not to be such. We also discuss the peculiar case of Terzan 5, which may represent a unique case of a cluster–cluster merger.

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An Anionic Ryanoid, 10-O-succinoylryanodol, Provides Insights into the Mechanisms Governing the Interaction of Ryanoids and the Subsequent Altered Function of Ryanodine-receptor Channels

The Journal of General Physiology ◽

10.1085/jgp.200208753 ◽

2003 ◽

Vol 121 (6) ◽

pp. 551-561 ◽

Cited By ~ 8

Author(s):

Bhavna Tanna ◽

William Welch ◽

Luc Ruest ◽

John L. Sutko ◽

Alan J. Williams

Keyword(s):

Ryanodine Receptor ◽

Transmembrane Potential ◽

Voltage Dependence ◽

Major Influence ◽

Ionic Interactions ◽

Receptor Affinity ◽

Flexible Molecule ◽

Ion Translocation ◽

Conductance States ◽

Conductance State

We have investigated the interactions of a novel anionic ryanoid, 10-O-succinoylryanodol, with individual mammalian cardiac muscle ryanodine receptor channels under voltage clamp conditions. As is the case for all ryanoids so far examined, the interaction of 10-O-succinoylryanodol with an individual RyR channel produces profound alterations in both channel gating and rates of ion translocation. In the continued presence of the ryanoid the channel fluctuates between periods of normal and modified gating, indicating a reversible interaction of the ligand with its receptor. Unlike the majority of ryanoids, we observe a range of different fractional conductance states of RyR in the presence of 10-O-succinoylryanodol. We demonstrate that 10-O-succinoylryanodol is a very flexible molecule and propose that each fractional conductance state arises from the interaction of a different conformer of the ryanoid molecule with the RyR channel. The probability of channel modification by 10-O-succinoylryanodol is dependent on the transmembrane holding potential. Comparison of the voltage dependence of channel modification by this novel anionic ryanoid with previous data obtained with cationic and neutral ryanoids reveals that the major influence of transmembrane potential on the probability of RyR channel modification by ryanoids results from an alteration in receptor affinity. These investigations also demonstrate that the charge of the ryanoid has a major influence on the rate of association of the ligand with its receptor indicating that ionic interactions are likely to be involved in this reaction.

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Hybrid sterility genes in mice (Mus musculus): a peculiar case of PRDM9 incompatibility

Trends in Genetics ◽

10.1016/j.tig.2021.06.008 ◽

2021 ◽

Author(s):

Jiri Forejt ◽

Petr Jansa ◽

Emil Parvanov

Keyword(s):

Mus Musculus ◽

Hybrid Sterility ◽

Peculiar Case ◽

Sterility Genes

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Retinal obliterative vasculitis associated to contralateral retinal neovascularization in membranoproliferative glomerulonephritis

European Journal of Ophthalmology ◽

10.1177/11206721211014384 ◽

2021 ◽

pp. 112067212110143

Author(s):

Michele Nicolai ◽

Alessandro Franceschi ◽

Nicola Vito Lassandro ◽

Paolo Pelliccioni ◽

Luca Danieli ◽

...

Keyword(s):

Retinal Vein Occlusion ◽

Branch Retinal Vein Occlusion ◽

Membranoproliferative Glomerulonephritis ◽

Vision Loss ◽

Vascular Occlusion ◽

Retinal Neovascularization ◽

Vein Occlusion ◽

Retinal Vascular Occlusion ◽

Contralateral Eye ◽

Peculiar Case

Purpose: To report our experience with a peculiar case of asynchronous bilateral retinal vascular occlusion in a patient suffering from membranoproliferative glomerulonephritis. Case report: A 57-year-old dialysed male affected by membranoproliferative glomerulonephritis who underwent kidney transplantation complained of a sudden vision loss in his right eye (RE). His best-corrected visual acuity (BCVA) was 20/40 in RE and 20/20 in the left eye (LE); ophthalmological and fluorangiographic examinations revealed unilateral retinal obliterative vasculitis with panuveitis and apparent sparing of contralateral eye. About 6 months later the patient developed a branch retinal vein occlusion associated with a papillary neovascular membrane in LE. Corticosteroid therapy was administered and immunosuppressant dosage was increased with macular oedema reduction in both events. Conclusion: We report a case of unilateral retinal obliterative vasculitis and subsequent contralateral retinal neovascularization and branch retinal vein occlusion in a patient affected by membranoproliferative glomerulonephritis.

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