Trapping of Unsaturated Small Molecules through Cyclization with Iron−Iminophosphorane Complexes

The iron−iminophosphorane−carbonyl complex Cp*(CO)2Fe{P(NPh)(OMe)2} (1; Cp* stands for η5-C5Me5) reacted with the activated alkyne dimethyl acetylenedicarboxylate (DMAD) to give in which the alkyne was trapped between the imino nitrogen and one carbonyl carbon to form a six-membered metallacycle. In contrast, 1 reacted with CO2 to afford aza-Wittig-type metathesis products, PhNCNPh and oxophosphorane (phosphonate) complex Cp*(CO)2Fe{P(O)(OMe)2}, probably via a four-membered aza-phosphacycle as an intermediate. Free acetonitrile did not react with 1, while the coordinated acetonitrile in [Cp*(CO)(NCMe)Fe{P(NHPh)(OMe)2}]PF6 was incorporated into a five-membered metallacycle through a base-catalyzed rearrangement to give in which the nitrile carbon was bonded to the imino nitrogen. It was proposed that this intramolecular cyclization reaction is initiated by the formation of the neutral iminophosphorane complex Cp*(CO)(NCMe)Fe{P(NPh)(OMe)2} as an intermediate, followed by the prompt nucleophilic attack of the resulting imino nitrogen to the carbon atom of the coordinated acetonitrile

NMR Study on a Novel Mucin from Jellyfish in Natural Abundance, Qniumucin from <i>Aurelia aurita</i>

A novel mucin (qniumucin), which we recently discovered in jellyfish, was investigated by several NMR techniques. Almost all the peaks in the 13C and proton NMR spectra were satisfactorily assigned to the amino acids in the main chain and to the bridging GalNAc, the major sugar in the saccharide branches. The amino acid sequence in the tandem repeat part (−VVETTAAP−) was reconfirmed by the cross-peaks between alpha protons and carbonyl carbons in the HMBC spectrum. A connectivity analysis around the O-glycoside bond (GalNAc−Thr) was also performed, and detailed information on the local configuration was obtained by the DPFGSE-NOE-HSD technique. The strategy and the results described in this paper can be extended to the structural analysis of general O-glycan chains, which are more complex than the present mucin. NMR analyses reveal the simple structure of qniumucin extracted by the present protocol, and the homogeneity and purity of qniumucin are probably the result of it being extracted from jellyfish, a primitive animal

Additional file 1 of Ten-year epidemiological study of ocular and orbital tumors in Chiba University Hospital

Additional file 1: Supplementary Figure 1. Graphical illustration of the frequencies of major malignant eyelid tumors

Mucin (Qniumucin), a Glycoprotein from Jellyfish, and Determination of Its Main Chain Structure

We extracted a novel glycoprotein, a member of the mucin family, from five species of jellyfish with high yields (1%−3% dry weight, 0.02%−0.1% wet weight) and determined its main chain structure and molecular mass. The glycoprotein contains unique tandem repeats of eight amino acids, of which two threonine residues are probably glycosylated by N-acetyl-d-galactosamine (GalNAc). We named this substance, which is common in jellyfish and similar to the human mucin MUC5AC, “qniumucin” and suggested the utilization of this compound as a new marine resource

Result of optical coherence tomography and visual function tests.

<p>Result of optical coherence tomography and visual function tests.</p

Boxplot and beeswarm plot of retinal sensitivity and intra-retinal layer thickness evaluated by optical coherence tomography.

The boxplot and the overlaid beeswarm plot showing the results of retinal sensitivity (RS) and optical coherence tomography (OCT) evaluation obtained from neuromyelitis optica spectrum disorder (NMO) group and healthy control (HC) group. (A) The result of retinal sensitivity (RS) of the central 10° area of retina. (B) The result of RS of the area between central 10° and 2° of the retina. (C) The result of RS evaluated from central 2°. (D), (E) The result of outer nuclear layer (ONL) thickness and average macular thickenss (AMT), respectively. *P <0.05.</p

Retinal Morphology and Sensitivity Are Primarily Impaired in Eyes with Neuromyelitis Optica Spectrum Disorder (NMOSD)

<div><p>Background</p><p>Previous studies of neuromyelitis optica spectrum disorder (NMOSD) using spectral domain optical coherence tomography (SD-OCT) showed that the outer nuclear layer (ONL) in eyes without a history of optic neuritis (ON) was thinner than that of healthy controls. It remains unclear whether the ONL thinning is caused by a direct attack on the retina by an autoantibody or a retrograde degeneration.</p><p>Objective</p><p>To determine the mechanisms involved in the retinal damage in eyes with NMOSD without ON.</p><p>Methods</p><p>SD-OCT was used to determine the thicknesses of the different retinal layers of 21 eyes of 12 NMOSD patients without prior ON and 19 eyes of 10 healthy controls. Eyes with peripapillary retinal nerve fiber layer (RNFL) thinning were excluded to eliminate the confounding effects of retrograde degeneration. Microperimetry was used to determine the central retinal sensitivity. The data of the two groups were compared using generalized estimated equation models to account for inter-eye dependencies.</p><p>Results</p><p>The ganglion cell plus inner plexiform layer and the inner nuclear layer plus outer plexiform layer thicknesses of the NMOSD eyes were not significantly different from that of the control eyes (<i>P</i> = 0.28, <i>P</i> = 0.78). However, the ONL and average macular thickness (AMT) in the NMOSD eyes were significantly thinner than that of the control eyes (<i>P</i> = 0.022, <i>P</i> = 0.036). The retinal sensitivity in the central 10°, 10° to 2°, and 2° sectors were significantly lower in the NMOSD eyes than in the control eyes (<i>P</i> = 0.013, <i>P</i> = 0.022, <i>P</i> = 0.002).</p><p>Conclusions</p><p>The ONL thinning, AMT thinning, and reduced retinal sensitivity in eyes with NMOSD without significant peripapillary RNFL thinning are most likely due to direct retinal pathology.</p></div

Evaluation of retinal sensitivity.

<p>The retinal sensitivities were obtained from 37 points within the central 10 degrees of the foveal center. The average retinal sensitivity of the central 10°, central 10° to 2°, and central 2° were calculated. The macular integrity assessment (MAIA) was used to determine the retinal sensitivity. (A) Retinal sensitivity of a healthy control eye. Retinal sensitivities obtained from each point are shown on the left. The average sensitivity of central 10° and the histogram of threshold frequencies compared with built-in database of normal population are shown on the right. (B) Retinal sensitivity of an eye with neuromyelitis optica spectrum disorder (NMOSD). The patient was a 66-year-old woman who had history of longitudinally extensive transverse myelitis and was positive for serum autoantibody against aquaporin-4. The average retinal sensitivity of the central 10° was 27.0 dB whereas the average sensitivity of healthy control eyes was 29.39 dB.</p

Clinical characteristics of patients with NMOSD.

<p>Clinical characteristics of patients with NMOSD.</p

Hypothesis of different mechanisms between retrograde degeneration and direct retinal pathology.

<p>(A) In retrograde degeneration of neuromyelitis optica spectrum disorder (NMOSD), involvement of anterior visual pathway results in a thinning of the inner retinal layers including the retinal nerve fiber layer(RNFL) and ganglion cell-inner plexiform layer (GCIP). (B) In direct retinal pathology of NMOSD, a direct attack of Müller cells by anti-aquaporin 4 (AQP4) antibody results in a secondary loss of retinal neurons including ONL thinning.</p