9 research outputs found
Circular Dichroic Power of Chiral Spiro Aromatics. Theoretical Calculation of the CD and UV Spectra of 2,2\u27 -Spirobi [2Hbenzeindene ] Derivatives
The CD and UV spectra of (2S)-2,2\u27-spirobi[2H-benz[e]indene]-
1,1\u27(3H,3\u27H)-dione (2) and (IR,I\u27S,2S)-I,I\u27,3,3\u27-tetrahydro-2,2\u27-spirobi[
2H -benz[e]indene]-I,I\u27 -diyl diacetate (3) were theoretical1y
calculated by the application of the Jt-electron SCF-CI-DV MO
method. The shape of component CD and UV bands was approximated by method (A) of the Gaussian distribution, or by method (B) employing the observed band shape of the UV spectra of
model compounds. The calculated CD and UV curves were in
good agreement with the observed ones. For compound 2, method
(A), calcd CD, Aox! = 318.5 nm (As = +5.8), 250.0 (-63.7), 213.7
(+90.8); obsd. CD, J"" = 336.2 nm (1\u2711; = +11.9), 253.2 (-96.1), 214.0 (+ 1\u2712.1). For compound 3, method (A), calcd CD, J,e,! = 279.3 nm (As = +6.5), 224.2 (-590.2), 213.7 (+753.7); obsd. CD, J\u27e" = 285.0 nm (As = +4.4), 230.2 (-961.5), 221.6 (+567.1). The absolute stereostructures of chiral spiro aromatics 2 and have been thus established by the calculation. The mechanism of the widely spread and weak CD Cotton effects of diketone 2 has been also clarified by the calculation. The calculated CD and UV spectral curves of compound 3 obtained by the application of method (B) were in
excellent agreement with the observed ones: calcd CD, Ae<t = 282.5
nm (As = +10.2), 231.5 (-1139.5), 221.2 (+474.0); obsd. CD, J,,,! =
285.0 nm (As = + 4.4), 230.2 (-961.5), 221.6 (+ 567.1)
Progressive stenosis and radiological findings of vasculitis over the entire internal carotid artery in moyamoya vasculopathy associated with graves’ disease: a case report and review of the literature
Abstract Background Moyamoya vasculopathy (MMV) associated with Graves’ disease (GD) is a rare condition resulting in ischemic stroke accompanied by thyrotoxicity. Radiological findings of vasculitis have been reported in the walls of distal internal carotid arteries (ICAs) in these patients; however, no reports have described in detail the processes of progression of the lesions in the proximal ICA. Moreover, treatments to prevent recurrence of ischemic stroke and progression of MMV have not yet been sufficiently elucidated. Case presentation We report a progressive case of MMV associated with GD and review the literature to clarify relationships among recurrence, progression, thyrotoxicity and treatment. Our patient developed cerebral infarction during thyrotoxicity with no obvious stenosis of ICAs. Five months later, transient ischemic attacks recurred with thyrotoxicity. Antiplatelet therapy and intravenous methylprednisolone stopped the attacks. Stenosis of the left ICA from the proximal to distal portion and champagne bottle neck sign (CBN) were found. She declined any surgery. Afterward, gradual progression with mild thyrotoxicity was observed. Eventually, we found smooth, circumferential, concentric wall thickening with diffuse gadolinium enhancement of the left ICA from the proximal to the distal portion on T1-weighted imaging, suggesting vasculitis radiologically. The clinical and radiological similarities to Takayasu arteritis encouraged us to provide treatment as for vasculitis of medium-to-large vessels. In a euthyroid state and after administration of prednisolone and methotrexate, improved flow in the cerebrovascular arteries on magnetic resonance angiography was observed. Based on our review of the literature, all cases with recurrence or progression were treated with anti-thyroid medication (ATM) alone and accompanied by thyrotoxicity. CBN was observed in all previous cases for which images of the proximal ICA were available. Conclusions We report the details of progressive stenosis from a very early stage and radiological findings of vasculitis over the entire ICA in MMV associated with GD. Cerebral infarction can occur with no obvious stenosis of the ICA. We treated the patient as per vasculitis of a medium-to-large vessel. Management of GD by ATM alone seems risky in terms of recurrence. Adequate management of GD and possible vasculitis may be important for preventing recurrence and progression
Negligible immunogenicity of terminally differentiated cells derived from induced pluripotent or embryonic stem cells.
The advantages of using induced pluripotent stem cells (iPSCs) instead of embryonic stem (ES) cells in regenerative medicine centre around circumventing concerns about the ethics of using ES cells and the likelihood of immune rejection of ES-cell-derived tissues. However, partial reprogramming and genetic instabilities in iPSCs could elicit immune responses in transplant recipients even when iPSC-derived differentiated cells are transplanted. iPSCs are first differentiated into specific types of cells in vitro for subsequent transplantation. Although model transplantation experiments have been conducted using various iPSC-derived differentiated tissues and immune rejections have not been observed, careful investigation of the immunogenicity of iPSC-derived tissue is becoming increasingly critical, especially as this has not been the focus of most studies done so far. A recent study reported immunogenicity of iPSC- but not ES-cell-derived teratomas and implicated several causative genes. Nevertheless, some controversy has arisen regarding these findings. Here we examine the immunogenicity of differentiated skin and bone marrow tissues derived from mouse iPSCs. To ensure optimal comparison of iPSCs and ES cells, we established ten integration-free iPSC and seven ES-cell lines using an inbred mouse strain, C57BL/6. We observed no differences in the rate of success of transplantation when skin and bone marrow cells derived from iPSCs were compared with ES-cell-derived tissues. Moreover, we observed limited or no immune responses, including T-cell infiltration, for tissues derived from either iPSCs or ES cells, and no increase in the expression of the immunogenicity-causing Zg16 and Hormad1 genes in regressing skin and teratoma tissues. Our findings suggest limited immunogenicity of transplanted cells differentiated from iPSCs and ES cells