CCR7 Signals Are Essential for Cortex–Medulla Migration of Developing Thymocytes

Upon TCR-mediated positive selection, developing thymocytes relocate within the thymus from the cortex to the medulla for further differentiation and selection. However, it is unknown how this cortex–medulla migration of thymocytes is controlled and how it controls T cell development. Here we show that in mice deficient for CCR7 or its ligands mature single-positive thymocytes are arrested in the cortex and do not accumulate in the medulla. These mutant mice are defective in forming the medullary region of the thymus. Thymic export of T cells in these mice is compromised during the neonatal period but not in adulthood. Thymocytes in these mice show no defects in maturation, survival, and negative selection to ubiquitous antigens. TCR engagement of immature cortical thymocytes elevates the cell surface expression of CCR7. These results indicate that CCR7 signals are essential for the migration of positively selected thymocytes from the cortex to the medulla. CCR7-dependent cortex–medulla migration of thymocytes plays a crucial role in medulla formation and neonatal T cell export but is not essential for maturation, survival, negative selection, and adult export of thymocytes

Assessment of Outcome of Hepatic Arterial Infusion Chemotherapy in Patients with Advanced Hepatocellular Carcinoma by the Combination of RECIST and Tumor Markers

To assess the outcome of stable disease (SD) patients with advanced hepatocellular carcinoma (HCC) by tumor markers after the first course of hepatic arterial infusion chemotherapy (HAIC). The study subjects were 156 HCC patients treated with HAIC and classified as Child Pugh A, with no extrahepatic metastasis, and no history of sorafenib treatment. In the study and validation cohorts, the AFP and DCP ratios of patients who were considered SD to the first course of HAIC were analyzed by AUROC for a prediction of response to the second course of HAIC. The imaging response to the first course of HAIC was classified as partial response (PR), SD and progressive disease (PD) in 29 (18.8%), 80 (51.9%), and 44 (28.6%) patients respectively. For SD patients, the α-fetoprotein (AFP) and des-γ-carboxy prothrombin (DCP) ratios of patients who were considered SD to the first course of HAIC were analyzed by the receiver operating characteristic curve for prediction of response to the second course of HAIC in the study cohorts. The area under the curve of AFP ratio was 0.743. The area under the curve of DCP ratio was 0.695. The cut-off values of AFP and DCP ratios were 1.3 and 1.0, respectively. In the validation cohort, the accuracy of the prediction of response in this validation cohort (71.4%) showed no significant difference compared to that in the study cohort (72.4%) (p = 1.0). The results suggested that patients with a high tumor marker ratio could be switched to alternative therapeutic regimens despite the SD response to HAIC

Anti-vasospastic Effects of Epidermal Growth Factor Receptor Inhibitors After Subarachnoid Hemorrhage in Mice

application/pdfSubarachnoid hemorrhage (SAH) is a devastating disease. Cerebral vasospasm is still an important cause of post-SAH poor outcomes, but its　mechanisms remain unveiled. Activation of epidermal growth factor receptor (EGFR) is suggested to cause vasoconstriction in vitro, but no report has demonstrated the involvement of EGFR in vasospasm development after SAHin vivo. Cross-talk of EGFR and vascular　endothelial growth factor (VEGF)　receptor, which may affect post-SAH vasospasm, was also reported in cancer cells, but has not been demonstrated in post-SAH vasospasm. The aim of this study was to investigate whether EGFR as well as EGFR-VEGF receptor crosstalk engage in the development of cerebral vasospasm in a mouse　SAH model. C57BL6 mice underwent endovascular perforation SAH or sham modeling. At 30 min post-modeling, mice were randomly administrated vehicle or 2 doses of selective EGFR inhibitors intracerebroventricularly. A higher dose of the inhibitor significantly prevented post-SAH neurological impairments at 72 h and vasospasm at 24 h associated with suppression of post-SAH activation of EGFR and extracellular signal-regulated kinase (ERK) 1/2 in the cerebral artery wall, especially in the smooth muscle cell layers. Anti-EGFR neutralizing antibody also showed similar effects. However, neither expression levels of VEGF nor activation levels of a major receptor of VEGF, VEGF receptor-2, were affected by SAH and two kinds of EGFR inactivation. Thus, this study first showed that EGFR-ERK1/2 pathways may be involved in post-SAH vasospasm development, and that EGFR-VEGF receptor cross-talk may not play a significant role in the development of vasospasm in mice.本文/Department of Neurosurgery, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu, Mie 514-8507, Japan11

Anti-vasospastic Effects of Epidermal Growth Factor Receptor Inhibitors After Subarachnoid Hemorrhage in Mice

application/pdf内容の要旨・審査結果の要旨 / 三重大学大学院医学系研究科 生命医科学専攻 臨床医学系講座 脳神経外科学分

Crystal Structure, Optical Properties, and Electronic Structure of Calcium Strontium Tungsten Oxynitrides CaxSr1-xWO2N

Novel calcium strontium tungsten oxynitrides CaxSr(1-x)WO(2)N (x = 0.25 and 0.5) have been synthesized. The crystal and electronic structures, electron-density distribution, and optical properties of CaxSr(1-x)WO(2)N and CaxSr(1-x)WO(2)N (x = 0, 0.25, and 0.5) have been investigated by neutron, synchrotron, and X-ray powder diffraction; transmission electron microscopy energy-dispersive spectroscopy (TEMEDS); scanning electron microscopy; UV visible reflectance measurements; and ab initio density functional theory (DFT)based calculations. Precursor materials CaxSr(1-x)WO(2)N (x = 0, 0.25, 0.5, and 1) with a scheelite-type structure were prepared by solid-state reactions, and heated at 900 degrees C for 5 h under an ammonia flow. The main phase in the product for the composition x = 1 was metallic tungsten W, whereas cubic Pm3m perovskite-type oxynitrides CaxSr(1-x)WO(2)N were obtained for the compositions x = 0, 0.25, and 0.5. The unit-cell parameter a of the cubic perovskite-type CaxSr(1-x)WO(2)N obtained from the Rietveld analysis of synchrotron X-ray and neutron powder diffraction data decreases with an increase of Ca concentration x (0 < x < 0.5), which indicates the substitution of Ca for Sr. The existence of nitrogen in CaxSr(1-x)WO(2)N was confirmed by (I) the refined occupancy factor in the Rietveld analysis of neutron data and (2) EDS. The maximum-entropy-method electron-density analysis combined with the DFT calculations indicates W N and W-O covalent bonds in CaxSr1_xWO2N, which are formed by the overlapping of W 5d and anion 2p orbitals. The minimum electron density at the W N bond is higher than that at the W-0 one, which indicates that the W N bond is more covalent due to the smaller difference in the electronegativity between W and N atoms compared to the W and O ones: The oxidation number of W in CaxSr(1-x)WO(2)N was estimated to be 5.2 by bond valence sum, which indicates the W5+ ion with the 5di electron configuration. Precursor oxides Ca Sr,,WO, with W6* having the 5cl electron configuration are white and insulating, whereas the CaxSr(1-x)WO(2)N oxynitrides with the W5* ion having the 5di configuration are black and exhibit metallic character. These results indicate the insulator metal transition from the d oxide CaxSr(1-x)WO(2)N to the di oxynitride CaxSr(1-x)WO(2)N. © 2013, American Chemical Society

Crystal Structure, Optical Properties, and Electronic Structure of Calcium Strontium Tungsten Oxynitrides Ca_<i>x</i>Sr_1–<i>x</i>WO₂N

Novel calcium strontium tungsten oxynitrides Ca_<i>x</i>Sr_1–<i>x</i>­WO₂N (<i>x</i> = 0.25 and 0.5) have been synthesized. The crystal and electronic structures, electron-density distribution, and optical properties of Ca_<i>x</i>Sr_1–<i>x</i>­WO₂N and Ca_<i>x</i>Sr_1–<i>x</i>­WO₄ (<i>x</i> = 0, 0.25, and 0.5) have been investigated by neutron, synchrotron, and X-ray powder diffraction; transmission electron microscopy energy-dispersive spectroscopy (TEM-EDS); scanning electron microscopy; UV–visible reflectance measurements; and ab initio density functional theory (DFT)-based calculations. Precursor materials Ca_<i>x</i>Sr_1–<i>x</i>­WO₄ (<i>x</i> = 0, 0.25, 0.5, and 1) with a scheelite-type structure were prepared by solid-state reactions, and heated at 900 °C for 5 h under an ammonia flow. The main phase in the product for the composition <i>x</i> = 1 was metallic tungsten W, whereas cubic <i>Pm</i>3̅<i>m</i> perovskite-type oxynitrides Ca_<i>x</i>Sr_1–<i>x</i>­WO₂N were obtained for the compositions <i>x</i> = 0, 0.25, and 0.5. The unit-cell parameter <i>a</i> of the cubic perovskite-type Ca_<i>x</i>Sr_1–<i>x</i>­WO₂N obtained from the Rietveld analysis of synchrotron X-ray and neutron powder diffraction data decreases with an increase of Ca concentration <i>x</i> (0 ≤ <i>x</i> ≤ 0.5), which indicates the substitution of Ca for Sr. The existence of nitrogen in Ca_<i>x</i>Sr_1–<i>x</i>­WO₂N was confirmed by (1) the refined occupancy factor in the Rietveld analysis of neutron data and (2) EDS. The maximum-entropy-method electron-density analysis combined with the DFT calculations indicates W–N and W–O covalent bonds in Ca_<i>x</i>Sr_1–<i>x</i>­WO₂N, which are formed by the overlapping of W 5d and anion 2p orbitals. The minimum electron density at the W–N bond is higher than that at the W–O one, which indicates that the W–N bond is more covalent due to the smaller difference in the electronegativity between W and N atoms compared to the W and O ones. The oxidation number of W in Ca_<i>x</i>Sr_1–<i>x</i>­WO₂N was estimated to be 5.2 by bond valence sum, which indicates the W⁵⁺ ion with the 5d¹ electron configuration. Precursor oxides Ca_<i>x</i>Sr_1–<i>x</i>­WO₄ with W⁶⁺ having the 5d⁰ electron configuration are white and insulating, whereas the Ca_<i>x</i>Sr_1–<i>x</i>­WO₂N oxynitrides with the W⁵⁺ ion having the 5d¹ configuration are black and exhibit metallic character. These results indicate the insulator–metal transition from the d⁰ oxide Ca_<i>x</i>Sr_1–<i>x</i>­WO₄ to the d¹ oxynitride Ca_<i>x</i>Sr_1–<i>x</i>­WO₂N

Viral-mediated temporally controlled dopamine production in a rat model of Parkinson disease.

International audienceRegulation of gene expression is necessary to avoid possible adverse effects of gene therapy due to excess synthesis of transgene products. To reduce transgene expression, we developed a viral vector-mediated somatic regulation system using inducible Cre recombinase. A recombinant adeno-associated virus (AAV) vector expressing Cre recombinase fused to a mutated ligand-binding domain of the estrogen receptor alpha (CreER(T2)) was delivered along with AAV vectors expressing dopamine-synthesizing enzymes to rats of a Parkinson disease model. Treatment with 4-hydroxytamoxifen, a synthetic estrogen receptor modulator, activated Cre recombinase within the transduced neurons and induced selective excision of the tyrosine hydroxylase (TH) coding sequence flanked by loxP sites, leading to a reduction in transgene-mediated dopamine synthesis. Using this strategy, aromatic L-amino acid decarboxylase (AADC) activity was retained so that l-3,4-dihydroxyphenylalanine (L-dopa), a substrate for AADC, could be converted to dopamine in the striatum and the therapeutic effects of L-dopa preserved, even after reduction of TH expression in the case of dopamine overproduction. Our data demonstrate that viral vector-mediated inducible Cre recombinase can serve as an in vivo molecular switch, allowing spatial and temporal control of transgene expression, thereby potentially increasing the safety of gene therapy