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1.
Phys Chem Chem Phys ; 25(37): 25408-25419, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37706318

RESUMEN

Directional fragment ejection from a tetrahedral molecule CH4 in linearly polarized two-color (ω and 2ω) asymmetric intense laser fields (50 fs, 1.4 × 1014 W cm-2, 800 nm and 400 nm) has been studied by three-dimensional ion coincidence momentum imaging. The H+ fragment produced from dissociative ionization, CH4 → H+ + CH3 + e-, is preferentially ejected on the larger amplitude side of the laser electric fields. Comparison with theoretical predictions by weak-field asymptotic theory shows that the observed asymmetry can be understood by the orientation selective tunneling ionization from the triply degenerated highest occupied molecular orbital (1t2) of CH4. A similar directional ejection of H+ was also observed for the low kinetic energy components of the two-body Coulomb explosion, CH4 → H+ + CH3+ + 2e-. On the other hand, the fragment ejection in the opposite direction were observed for the high energy component, as well as H2+ produced from the Coulomb explosion CH4 → H2+ + CH2+ + 2e-. Possible origins of the characteristic fragmentation are discussed.

2.
Phys Chem Chem Phys ; 24(15): 8962-8969, 2022 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-35380001

RESUMEN

Dissociative tunneling ionization of tetrafluoromethane (CF4) in circularly polarized ultrashort intense laser fields (35 fs, 0.8 × 1014 W cm-2, 1035 nm), CF4 → CF4+ + e- → CF3+ + F + e-, has been studied by three-dimensional electron-ion coincidence momentum imaging. The photoelectron angular distribution in the recoil frame revealed that the dissociative tunneling ionization occurs efficiently when the laser electric field points from F to C. The obtained results are qualitatively consistent with the theoretical predictions by the weak-field asymptotic theory (WFAT) for tunneling ionization from the highest and next-highest occupied molecular orbitals, HOMO (1t1), and HOMO-1 (4t2), respectively. On the other hand, the angular distribution shows clear dependences on the polarization helicity, indicating that the breaking of the C-F bonds is sensitive to the helicity of the multicycle circularly polarized laser fields.

3.
Phys Rev Lett ; 124(19): 193201, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32469563

RESUMEN

Ultrafast multiphoton ionization of Xe in strong extreme ultraviolet free-electron laser (FEL) fields (91 eV, 30 fs, 1.6×10^{12} W/cm^{2}) has been investigated by multielectron-ion coincidence spectroscopy. The electron spectra recorded in coincidence with Xe^{4+} show characteristic features associated with two-photon absorption to the 4d^{-2} double core-hole (DCH) states and subsequent Auger decay. It is found that the pathway via the DCH states, which has eluded clear identification in previous studies, makes a large contribution to the multiple ionization, despite the long FEL pulse duration compared with the lifetime of the 4d core-hole states.

4.
Qual Life Res ; 29(11): 2961-2975, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32529343

RESUMEN

PURPOSE: The diagnosis and treatment of cancer negatively affect patients' physical, functional and psychological wellbeing. Patients' needs for care cannot be addressed unless they are recognized by healthcare providers (HCPs). The use of quality of life (QoL) assessments with feedback to HCPs might facilitate the identification and discussion of QoL-topics. METHODS: 113 patients with stage I-IIIB breast cancer treated with chemotherapy were included in this randomized controlled trial. Patients were randomly allocated to receive either usual care, or usual care with an intervention consisting of a QoL-monitor assessing QoL, distress and care needs before every chemotherapy cycle visit. Patients completed questionnaires regarding QoL, illness perceptions, self-efficacy, and satisfaction with communication. From the 2nd visit onwards, patients in the intervention arm and their HCPs received a copy of the QoL overview and results were shown in patients' medical files. Audio-recordings and patients' self-reports were used to investigate effects on communication, patient management and patient-wellbeing. A composite score for communication was calculated by summing the number of QoL-topics discussed during each consultation. RESULTS: Use of the QoL-monitor resulted in a higher communication score (0.7 topics increase per visit, p = 0.04), especially regarding the disease-specific and psychosocial issues (p < 0.01). There were no differences in patient management, QoL, illness perceptions or distress. Patients in the experimental arm (n = 60) had higher scores on satisfaction with communication (p < 0.05). CONCLUSIONS: Use of a QoL-monitor during chemotherapy in patients with early breast cancer might result in a more frequent discussion of QoL-topics, associated with high levels of patients' satisfaction.


Asunto(s)
Neoplasias de la Mama/psicología , Detección Precoz del Cáncer/métodos , Calidad de Vida/psicología , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Encuestas y Cuestionarios , Suecia , Adulto Joven
5.
Breast Cancer Res Treat ; 166(2): 459-471, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28762012

RESUMEN

PURPOSE: Cultural differences are hypothesized to influence patients' Quality of Life (QoL) reports. However, there is a lack of empirical cross-cultural studies comparing QoL of patients with cancer. This study aims to compare QoL of women with breast cancer in the Netherlands and Japan, and to investigate the association of QoL with sociodemographic, clinical, and psychological variables (illness perceptions). METHODS: Dutch (n = 116) and Japanese (n = 148) women with early breast cancer undergoing chemotherapy completed the EORTC QLQ-C30 and Brief Illness Perception Questionnaire immediately before their second cycle of chemotherapy. RESULTS: Dutch women reported poorer Physical, Role, Emotional, and Cognitive functioning than Japanese women. Additionally, illness perceptions were significantly different in Japan and the Netherlands, but these did not vary across treatment type. In Japan, QoL of women receiving AC-chemotherapy was better than that of women receiving FEC-chemotherapy, whereas in the Netherlands, QoL did not vary as a function of chemotherapy. Illness perceptions about symptom severity, adverse consequences, and emotional representations were negatively related to most domains of patients' QoL in both countries. Adding illness perceptions as covariates to the ANOVA analyses rendered the effects of country and treatment type on QoL non-significant. CONCLUSIONS: Comparing Dutch and Japanese women with early breast cancer revealed important differences in treatment modalities and illness perceptions which both appear to influence QoL. Perceptions about cancer have been found to vary across cultures, and our study suggests that these perceptions should be considered when performing cross-cultural studies focusing on patient-reported outcomes.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/psicología , Quimioterapia/psicología , Calidad de Vida/psicología , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Comparación Transcultural , Femenino , Humanos , Japón , Persona de Mediana Edad , Países Bajos , Resultado del Tratamiento
6.
Osteoarthritis Cartilage ; 24(7): 1190-9, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26944197

RESUMEN

OBJECTIVE: A number of promising compounds developed for osteoarthritic pain have failed to demonstrate clinical efficacy. To enhance preclinical translational research for osteoarthritis, a model of knee osteoarthritis pain was developed in Macaca fascicularis and the effects of two distinct pharmacological classes of drugs were tested on pain-related behavior. DESIGN: Behavioral assessments were developed specifically for the macaque. Baseline knee pressure threshold and weight bearing were assessed prior to a unilateral medial meniscectomy (MMx). Fifteen days following MMx, macaques underwent a once daily exercise regimen for 36 days. Sixty-seven days following MMx, macaques were assigned to one of three treatment groups (n = 3/group), either non-steroidal anti-inflammatory drug (NSAID) diclofenac, NK1 receptor antagonist aprepitant or vehicle, and treated for 5 days. Animals were tested 3-4 h after p.o. dosing and testing was performed blinded. Treatment utilized a crossover design-each animal received all treatments-and a 9-day washout period was utilized between treatments. RESULTS: Vehicle-treated macaques consistently demonstrated decreased ipsilateral pressure threshold ("hyperalgesia") and decreased weight bearing. While diclofenac increased weight bearing and pressure threshold, full attenuation of pain was not obtained. No significant improvement of either knee pressure or weight bearing was observed with aprepitant. CONCLUSIONS: Unilateral MMx in the macaque evoked pain-related behaviors and knee joint pathology reminiscent of osteoarthritis. The behavioral endpoints were sensitive to NSAID treatment but not sensitive to NK1 receptor block, which parallel clinical findings. The current macaque osteoarthritis model could be used to test potential treatments for osteoarthritis pain.


Asunto(s)
Dolor , Animales , Antiinflamatorios no Esteroideos , Articulación de la Rodilla , Macaca , Meniscectomía , Osteoartritis de la Rodilla
7.
Nanotechnology ; 27(29): 295603, 2016 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-27284690

RESUMEN

Typical thermostable and flexible polyimide polymers exhibit many excellent properties such as strong mechanical and chemical resistance. However, in contrast to single-crystal substrates like silicon or sapphire, polymers mostly display disordered and rough surfaces, which may result in instability and degradation of the interfaces between thin films and polymer substrates. As a step toward the development of next-generation polymer substrates, we here report single-atom-layer imprinting onto the polyimide sheets, resulting in an ultrasmooth 0.3 nm high atomic step-and-terrace surface on the polyimides. The ultrasmooth polymer substrates are expected to be applied to the fabrication of nanostructures such as superlattices, nanowires, or quantum dots in nanoscale-controlled electronic devices. We fabricate smooth and atomically stepped indium tin oxide transparent conducting oxide thin films on the imprinted polyimide sheets for future use in organic-based optoelectronic devices processed with nanoscale precision. Furthermore, toward 2D polymer substrate nanoengineering, we demonstrate nanoscale letter writing on the atomic step-and-terrace polyimide surface via atomic force microscopy probe scratching.

8.
Gene Ther ; 22(2): 127-37, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25503692

RESUMEN

Age-related macular degeneration (AMD) is a vision-threatening disease characterized by choroidal fibrovascular membrane (FVM) formation, choroidal neovascularization (CNV) and choroidal fibrosis. No safe and effective therapeutic method has been developed for the choroidal fibrosis, although anti-vascular endothelial growth factor therapy can partially shrink the CNV. We recently reported that periostin (POSTN), which is produced by retinal pigment epithelial cells, has an important role in the formation of preretinal FVMs, but its role in choroidal FVMs has not been determined. In this study, we used Postn knockout mice to investigate the role played by POSTN in choroidal FVM formation. In addition, we used a new class of RNA interference (RNAi) agent (NK0144) that targets POSTN and determined its effect on choroidal FVM development. Genetic ablation of Postn had an inhibitory effect not only on CNV formation but also on choroidal fibrosis in a mouse CNV model. NK0144 also had a greater inhibitory effect on both the CNV and choroidal fibrosis than control RNAi with no apparent adverse effects. These findings suggest a causal relationship between POSTN and choroidal FVM formation, and also a potential therapeutic role of intravitreal NK0144 for AMD.


Asunto(s)
Moléculas de Adhesión Celular/genética , Neovascularización Coroidal/terapia , Degeneración Macular/terapia , Interferencia de ARN , Animales , Secuencia de Bases , Adhesión Celular , Moléculas de Adhesión Celular/metabolismo , Movimiento Celular , Proliferación Celular , Células Cultivadas , Coroides/irrigación sanguínea , Coroides/patología , Técnicas de Silenciamiento del Gen , Terapia Genética , Humanos , Inyecciones Intravítreas , Ratones Endogámicos C57BL , Ratones Noqueados , Datos de Secuencia Molecular , ARN Interferente Pequeño/administración & dosificación , ARN Interferente Pequeño/genética , Epitelio Pigmentado de la Retina/patología , Epitelio Pigmentado de la Retina/fisiología , Receptor Toll-Like 3/metabolismo
9.
Clin Exp Allergy ; 44(2): 238-49, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24118172

RESUMEN

BACKGROUND: We recently reported that the interaction between Lyn and FcεRIß is indispensable for FcεRI-mediated human mast cell (MC) activation and that FcεRIß functions as an amplifier of FcεRI-mediated activation signal. Some of FcεRIß in cytoplasm appeared not to be co-localized with FcεRIα. The function of FcεRIß in the cytoplasm remains unknown. METHODS: The localization of FcεRIß and FcεRIα in giant papillae specimens from patients with allergic keratoconjunctivitis and of FcεRIß, FcεRIα, and Lyn in cultured human MCs was examined using confocal microscopy. FcεRIß was overexpressed using an adenovirus vector system. Mediators were measured by enzyme immunoassays or enzyme-linked immunosorbent assays. RESULTS: In the subepithelial region, FcεRIß was mainly localized in the cell membrane of MCs. In the perivascular region, FcεRIß expression was scattered throughout the cytoplasm and in the cell membrane of MCs. Overexpression of FcεRIß in MCs mainly increased its cytoplasmic expression and slightly up-regulated cell surface FcεRI expression. However, overexpression of FcεRIß in MCs resulted in down-regulation of the tyrosine phosphorylation levels of FcεRIß and Syk and down-regulation of the Ca(2+) influx soon after FcεRI aggregation and then resulted in down-regulation of degranulation, PGD2 synthesis, and production of a set of cytokines. This negative regulatory effect may be due to inhibition of the redistribution of Lyn to small patches within the plasma membrane. CONCLUSION: Cytoplasmic FcεRIß, which is not co-localized with FcεRIα, may function as a negative regulator, as it can capture important signalling molecules such as Lyn.


Asunto(s)
Señalización del Calcio , Regulación hacia Abajo , Hipersensibilidad/metabolismo , Queratoconjuntivitis/metabolismo , Mastocitos/metabolismo , Receptores de IgE/biosíntesis , Adulto , Línea Celular , Citoplasma , Femenino , Humanos , Hipersensibilidad/inmunología , Hipersensibilidad/patología , Péptidos y Proteínas de Señalización Intracelular/inmunología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Queratoconjuntivitis/inmunología , Queratoconjuntivitis/patología , Masculino , Mastocitos/inmunología , Mastocitos/patología , Proteínas Tirosina Quinasas/inmunología , Proteínas Tirosina Quinasas/metabolismo , Receptores de IgE/inmunología , Quinasa Syk , Familia-src Quinasas/inmunología , Familia-src Quinasas/metabolismo
10.
Allergy ; 68(11): 1467-70, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24118000

RESUMEN

Overproduction of periostin, an IL-13-inducible matricellular protein, despite corticosteroid treatment is thought to be involved in the chronicity of allergic inflammation seen in corticosteroid-refractory tissue fibrosis. Therefore, we hypothesized that some tissue cells must produce periostin in a corticosteroid-insensitive manner. Here, we show that IL-4 and IL-13 each induced comparable levels of periostin production by primary normal human fibroblasts and microvascular endothelial cells derived from lung and skin. Dexamethasone, a corticosteroid, completely inhibited IL-4/13-induced, but did not affect TGF-ß-induced, periostin production by fibroblasts. In contrast, dexamethasone synergistically enhanced IL-4/13-induced periostin production by microvascular endothelial cells. TGF-ß did not induce periostin production by microvascular endothelial cells. Our novel findings suggest that IL-4/13-induced microvascular endothelium-derived and/or TGF-ß-induced fibroblast-derived periostin might play a pivotal role in corticosteroid-refractory tissue fibrosis, leading to chronic allergic inflammation in the lung and/or skin.


Asunto(s)
Moléculas de Adhesión Celular/biosíntesis , Dexametasona/farmacología , Moléculas de Adhesión Celular/antagonistas & inhibidores , Sistema Libre de Células , Fibroblastos/inmunología , Fibroblastos/patología , Fibrosis/inmunología , Células Endoteliales de la Vena Umbilical Humana , Humanos , Mediadores de Inflamación/fisiología , Interleucina-13/fisiología , Interleucina-4/fisiología , Pulmón/inmunología , Pulmón/patología , Piel/inmunología , Piel/patología , Distribución Tisular/inmunología , Factor de Crecimiento Transformador beta1/fisiología
11.
J Appl Microbiol ; 115(3): 711-7, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23826728

RESUMEN

AIMS: Scedosporium apiospermum sometimes causes serious infectious diseases on the skin of immunodeficient subjects. Antifungal effects of fatty acid salts in soap against S. apiospermum were investigated under different water conditions. METHODS AND RESULTS: Ultrapure soft water (UPSW) was generated by the water softener with cation-exchange resin. The calcium and magnesium ions were replaced with sodium ions in UPSW. Scedosporium apiospermum was incubated with different fatty acid salts that constituted soap in distilled water (DW), tap water (TW) and UPSW. After incubation, the number of fungi was counted. Among the fatty acids, palmitic acid salt (C16) reduced the number of S. apiospermum. UPSW enhanced the antifungal effect of C16 on S. apiospermum. The absence of both calcium and magnesium ions and the existence of sodium chloride in UPSW were responsible for its antifungal effect. In addition, repeated short-term treatment with UPSW and C16 decreased the number of S. apiospermum. CONCLUSIONS: Antifungal effects of C16 on S. apiospermum were demonstrated. Moreover, the use of UPSW promoted the antifungal effect of C16. SIGNIFICANCE AND IMPACT OF STUDY: This study provides the preventive method for diseases associated with S. apiospermum infection using novel palmitic acid soap in UPSW.


Asunto(s)
Antifúngicos/farmacología , Ácido Palmítico/farmacología , Scedosporium/efectos de los fármacos , Agua/farmacología , Sales (Química)/farmacología , Jabones/química , Cloruro de Sodio/farmacología , Agua/química , Purificación del Agua , Ablandamiento del Agua
12.
J Chem Phys ; 138(23): 234708, 2013 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-23802977

RESUMEN

At low coverage of water on Cu(110), substrate-mediated electrostatics lead to zigzagging chains along [001] as observed with STM [T. Yamada, S. Tamamori, H. Okuyama, and T. Aruga, "Anisotropic water chain growth on Cu(110) observed with scanning tunneling microscopy" Phys. Rev. Lett. 96, 036105 (2006)]. Using x-ray absorption spectroscopy we find an anomalous low-energy resonance at ~533.1 eV which, based on density functional theory spectrum simulations, we assign to an unexpected configuration of water units whose uncoordinated O-H bonds directly face those of their neighbors; this interaction repeats over trough sites with enhanced electron density and is analogous to the case of a hydrated electron.

13.
Allergy ; 67(10): 1241-9, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22845063

RESUMEN

BACKGROUND: FcεRIß reportedly functions as an amplifier of the FcεRIγ-mediated activation signal using a reconstitution system. However, the amplification mechanisms in human mast cells (MCs) are poorly understood. We previously reported the hyperexpression of FcεRIß of MCs in giant papillae from vernal keratoconjunctivitis patients, compared with that in conjunctivae from nonallergic conjunctivitis patients. Elucidation of the molecular mechanisms of the amplification induced by FcεRIß should provide new targets for novel therapeutic interventions. The aim is to understand in greater details the function of FcεRIß in human MC FcεRI expression and signaling. METHODS: FcεRIß and Lyn expression was reduced using a lentiviral shRNA silencing technique. Localization of Lyn and FcεRIß in cultured MCs was examined by confocal microscopic analysis. Mediators were measured by ELISAs. RESULTS: The diminution of FcεRIß significantly downregulated cell surface FcεRI expression and FcεRI-mediated mediator release/production. The downregulation of FcεRI-mediated degranulation was not only due to the decrease in FcεRI expression. The diminution of FcεRIß inhibited the redistribution of Lyn within the cell membrane following IgE sensitization. The diminution of Lyn in MCs significantly downregulated FcεRI-mediated degranulation. The recombinant cell-penetrating forms of phosphorylated FcεRIß immunoreceptor tyrosine-based activation motif (ITAM) for intracellular delivery disturbed the interaction between Lyn and phosphorylated endogenous FcεRIß ITAM, resulted in inhibiting IgE-dependent histamine release from MCs in vitro and from giant papillae specimens ex vivo. CONCLUSION: The interaction between Lyn and FcεRIß is indispensable for FcεRI-mediated human MC activation, and specific inhibition of the interaction may represent a new therapeutic strategy for the treatment of human allergic diseases.


Asunto(s)
Mastocitos/inmunología , Receptores de IgE/inmunología , Familia-src Quinasas/metabolismo , Adulto , Degranulación de la Célula/inmunología , Células Cultivadas , Regulación hacia Abajo , Humanos , Receptores de IgE/metabolismo , Transducción de Señal
14.
J Chem Phys ; 136(3): 034702, 2012 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-22280772

RESUMEN

We report x-ray emission and absorption spectroscopy studies of the electronic structure of the predissociative α(3) phase of CO bound at hollow sites of Fe(100) as well as of the on-top bound species in the high-coverage α(1) phase. The analysis is supported by density functional calculations of structures and spectra. The bonding of "lying down" CO in the hollow site is well described in terms of π to π∗ charge transfer made possible through bonding interaction also at the oxygen in the minority spin-channel. The on-top CO in the mixed, high-coverage α(1) phase is found to be tilted due to adsorbate-adsorbate interaction, but still with bonding mainly characteristic of "vertical" on-top adsorbed CO similar to other transition-metal surfaces.


Asunto(s)
Monóxido de Carbono/química , Hierro/química , Teoría Cuántica , Espectrometría por Rayos X
15.
Phys Rev Lett ; 107(24): 243003, 2011 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-22242995

RESUMEN

Nonlinear, three-photon double excitation of He in intense extreme ultraviolet free-electron laser fields (∼24.1 eV, ∼5 TW/cm2) is presented. Resonances to the doubly excited states converging to the He+ N=3 level are revealed by the shot-by-shot photoelectron spectroscopy and identified by theoretical calculations based on the time-dependent Schrödinger equation for the two-electron atom under a laser field. It is shown that the three-photon double excitation is enhanced by intermediate Rydberg states below the first ionization threshold, giving a greater contribution to the photoionization yields than the two-photon process by more than 1 order of magnitude.

16.
J Exp Med ; 187(11): 1863-70, 1998 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-9607926

RESUMEN

CD45-AP specifically associates with CD45, a protein tyrosine phosphatase essential for lymphocyte differentiation and antigen receptor-mediated signal transduction. CD45 is thought to mediate antigen receptor signaling by dephosphorylating regulatory tyrosine residues on Src family protein tyrosine kinases such as Lck. However, the mechanism for regulating CD45 protein tyrosine phosphatase activity remains unclear. CD45-AP-null mice were created to examine the role of CD45-AP in CD45-mediated signal transduction. T and B lymphocytes showed reduced proliferation in response to antigen receptor stimulation. Both mixed leukocyte reaction and cytotoxic T lymphocyte functions of T cells were also markedly decreased in CD45-AP-null mice. Interestingly, the interaction between CD45 and Lck was significantly reduced in CD45-AP-null T cells, indicating that CD45-AP directly or indirectly mediates the interaction of CD45 with Lck. Our data indicate that CD45-AP is required for normal antigen receptor signaling and function in lymphocytes.


Asunto(s)
Antígenos Comunes de Leucocito/metabolismo , Proteínas de la Membrana , Fosfoproteínas/fisiología , Proteínas Tirosina Fosfatasas/metabolismo , Transducción de Señal , Animales , Linfocitos B , División Celular , Péptidos y Proteínas de Señalización Intracelular , Antígenos Comunes de Leucocito/biosíntesis , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Fosfoproteínas/genética , Proteínas Tirosina Fosfatasas/biosíntesis , Receptores de Antígenos de Linfocitos T alfa-beta/metabolismo , Linfocitos T
17.
Phys Rev Lett ; 105(13): 133001, 2010 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-21230767

RESUMEN

Photoelectron spectroscopy has been performed to study the multiphoton double ionization of Ar in an intense extreme ultraviolet laser field (hν ∼ 21 eV, ∼ 5 TW/cm²), by using a free electron laser (FEL). Three distinct peaks identified in the observed photoelectron spectra clearly show that the double ionization proceeds sequentially via the formation of Ar(+): Ar+hν→Ar (+) + e⁻ and Ar²(+) + 2hν→Ar(+) + e⁻. Shot-by-shot recording of the photoelectron spectra allows simultaneous monitoring of FEL spectrum and the multiphoton process for each FEL pulse, revealing that the two-photon ionization from Ar(+) is significantly enhanced by intermediate resonances in Ar(+).

18.
Aust Dent J ; 54(1): 49-53, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19228133

RESUMEN

This study presents the radiographic findings of two cases of static bone cavity in the inferior aspect of the condylar neck and mandibular notch of the mandible. On plain CT, a soft tissue mass was observed in each cavity. The submandibular gland and the other glands were not found in each cavity. On contrast-enhanced CT, the soft tissue in the cavity in the inferior aspect of the condylar neck had marked linear enhancement and dilated vasculature structure was observed in the cavity. On the contrast-enhanced MRI, the soft tissue in the cavity of the mandibular notch had marked enhancement and flow void was detected in the cavity. In the inferior aspect of the condylar neck, the cavity size had enlarged radiographically over a period of three years. Vascular lesions were found in the cavity located in the inferior aspect of the condylar neck and mandibular notch of the mandible by both CT and MRI. The vascular lesion might explain the enlargement of the static bone cavity.


Asunto(s)
Quistes Maxilomandibulares/patología , Enfermedades Mandibulares/patología , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Quistes Maxilomandibulares/irrigación sanguínea , Quistes Maxilomandibulares/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Enfermedades Mandibulares/diagnóstico por imagen , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
19.
Br J Cancer ; 99(9): 1442-52, 2008 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-18854835

RESUMEN

In a previous study, we showed that a novel anticancer drug, 1-(3-C-ethynyl-beta-D-ribo-pentofuranosyl)cytosine (TAS106, ECyd) increased the antitumour efficacy of X-irradiation. However, its effects on hypoxic cells in tumours remain unclarified. Here, we show that TAS106 enhances the induction of apoptosis in X-irradiated human gastric adenocarcinoma MKN45 and MKN28 cells under hypoxia in vitro. At the same time, the accumulation of HIF-1alpha observed under hypoxia was shown to be decreased to the level of normoxia in the presence of 0.1 microM TAS106. To study the function of HIF-1alpha protein in apoptosis of hypoxic cells, we employed an HIF-1alpha reductive approach using its specific antisense oligodeoxynucleotide. The reduction of HIF-1alpha gene expression dramatically enhanced X-ray-induced apoptosis in hypoxic cells. In in vivo experiments in which MKN45 cells were transplanted into severe combined immunodeficient (SCID) mice, TAS106 (0.5 mg kg(-1)) suppressed HIF-1alpha expression and subsequently reduced the area of the hypoxic region in the tumour and enhanced the induction of apoptosis in the hypoxic region when combined with 2 Gy of X-irradiation. These results suggest the possibility that TAS106 acts as a potent radiosensitiser through the inhibition of HIF-1alpha expression and can be a useful agent against radiotherapy-resistant hypoxic cells in solid tumours.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Subunidad alfa del Factor 1 Inducible por Hipoxia/antagonistas & inhibidores , Fármacos Sensibilizantes a Radiaciones/farmacología , Animales , Ciclo Celular , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Ratones , Ratones SCID , Neoplasias Experimentales/patología , Neoplasias Experimentales/terapia , Oligonucleótidos Antisentido/farmacología , Transcripción Genética/efectos de los fármacos , Uridina Quinasa/genética , Uridina Quinasa/fisiología , Factor A de Crecimiento Endotelial Vascular/genética , Terapia por Rayos X
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