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1.
Phys Chem Chem Phys ; 25(37): 25408-25419, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37706318

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-35380001

RESUMO

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.
Qual Life Res ; 29(11): 2961-2975, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32529343

RESUMO

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.


Assuntos
Neoplasias da Mama/psicologia , Detecção Precoce de Câncer/métodos , Qualidade de Vida/psicologia , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Inquéritos e Questionários , Suécia , Adulto Jovem
4.
Phys Rev Lett ; 124(19): 193201, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32469563

RESUMO

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.

5.
Transplant Proc ; 50(9): 2718-2722, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30401384

RESUMO

PURPOSE: After undergoing the Kasai procedure for biliary atresia (BA), most patients develop severe splenomegaly that tends to be improved by liver transplantation. However, fluctuations in splenic volume long after transplantation remain to be elucidated. PATIENTS AND METHODS: Seventy-one consecutive patients who had undergone pediatric living donor liver transplantation (LDLT) for BA were followed up in our outpatient clinic for 5 years. They were classified into 3 groups according to their clinical outcomes: a good course group (GC, n = 41) who were maintained on only 1 or without an immunosuppressant, a liver dysfunction group (LD, n = 18) who were maintained on 2 or 3 types of immunosuppressants, and a vascular complication group (VC, n = 11). Splenic and hepatic volumes were calculated by computed tomography in 464 examinations and the values compared before and after the treatment, especially in the VC group. RESULTS: Splenic volume decreased exponentially in the GC group, with splenic volume to standard spleen volume ratio (SD) being 1.59 (0.33) 5 years after liver transplantation. Splenic volume to standard spleen volume ratios were greater in the VC and LD groups than in the GC group. Patients in the VC group with portal vein stenosis developed liver atrophy and splenomegaly, whereas those with hepatic vein stenosis developed hepatomegaly and splenomegaly. Interventional radiation therapy tended to improve the associated symptoms. CONCLUSIONS: Fluctuations in splenic volume long after pediatric LDLT for BA may reflect various clinical conditions. Evaluation of both splenic and hepatic volumes can facilitate understanding clinical conditions following pediatric LDLT.


Assuntos
Atresia Biliar/cirurgia , Hepatomegalia/epidemiologia , Transplante de Fígado/efeitos adversos , Esplenomegalia/epidemiologia , Adolescente , Criança , Pré-Escolar , Feminino , Hepatomegalia/etiologia , Humanos , Fígado/patologia , Transplante de Fígado/métodos , Doadores Vivos , Masculino , Baço/patologia , Esplenomegalia/etiologia , Tomografia Computadorizada por Raios X
6.
Breast Cancer Res Treat ; 166(2): 459-471, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28762012

RESUMO

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.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/psicologia , Tratamento Farmacológico/psicologia , Qualidade de Vida/psicologia , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Comparação Transcultural , Feminino , Humanos , Japão , Pessoa de Meia-Idade , Países Baixos , Resultado do Tratamento
7.
Nanotechnology ; 27(29): 295603, 2016 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-27284690

RESUMO

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.
Osteoarthritis Cartilage ; 24(7): 1190-9, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26944197

RESUMO

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.


Assuntos
Dor , Animais , Anti-Inflamatórios não Esteroides , Articulação do Joelho , Macaca , Meniscectomia , Osteoartrite do Joelho
9.
Curr Med Chem ; 22(34): 3951-79, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26282943

RESUMO

The continued emergence of drug-resistance to existing antibacterial agents represents a severe and ongoing public health concern, which demands the discovery of new antibiotics. However the number of novel classes of antibacterial drugs launched in the clinic has been remarkably slow since the 1960s, and it is urgent to develop novel antibacterial agents to fight against drug-resistant bacterial pathogens. Peptidoglycan is a component of the bacterial cell wall, which consists of a repeated N-acetylmuramic acid (MurNAc) and Nacetylglucosamine (GluNAc) polymer cross-linked with polypeptides, and is a good target for antibacterial drug discovery. Among enzymes responsible for its biosynthesis, phospho-MurNAc-pentapeptide translocase (MraY) is a novel and promising target. Many nucleoside natural products, which strongly inhibit MraY, have been found in nature. This review will summarize the synthesis and biological properties of selected MraY inhibitory nucleoside natural products and their analogues synthesized in our laboratory and by others.


Assuntos
Antibacterianos/química , Proteínas de Bactérias/antagonistas & inibidores , Produtos Biológicos/química , Nucleosídeos/química , Transferases/antagonistas & inibidores , Antibacterianos/síntese química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Produtos Biológicos/farmacologia , Nucleosídeos/síntese química , Nucleosídeos/farmacologia , Relação Estrutura-Atividade , Transferases/metabolismo , Transferases (Outros Grupos de Fosfato Substituídos)
10.
Gene Ther ; 22(2): 127-37, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25503692

RESUMO

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.


Assuntos
Moléculas de Adesão Celular/genética , Neovascularização de Coroide/terapia , Degeneração Macular/terapia , Interferência de RNA , Animais , Sequência de Bases , Adesão Celular , Moléculas de Adesão Celular/metabolismo , Movimento Celular , Proliferação de Células , Células Cultivadas , Corioide/irrigação sanguínea , Corioide/patologia , Técnicas de Silenciamento de Genes , Terapia Genética , Humanos , Injeções Intravítreas , Camundongos Endogâmicos C57BL , Camundongos Knockout , Dados de Sequência Molecular , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Epitélio Pigmentado da Retina/patologia , Epitélio Pigmentado da Retina/fisiologia , Receptor 3 Toll-Like/metabolismo
11.
Clin Exp Allergy ; 44(2): 238-49, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24118172

RESUMO

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.


Assuntos
Sinalização do Cálcio , Regulação para Baixo , Hipersensibilidade/metabolismo , Ceratoconjuntivite/metabolismo , Mastócitos/metabolismo , Receptores de IgE/biossíntese , Adulto , Linhagem Celular , Citoplasma , Feminino , Humanos , Hipersensibilidade/imunologia , Hipersensibilidade/patologia , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Ceratoconjuntivite/imunologia , Ceratoconjuntivite/patologia , Masculino , Mastócitos/imunologia , Mastócitos/patologia , Proteínas Tirosina Quinases/imunologia , Proteínas Tirosina Quinases/metabolismo , Receptores de IgE/imunologia , Quinase Syk , Quinases da Família src/imunologia , Quinases da Família src/metabolismo
12.
Allergy ; 68(11): 1467-70, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24118000

RESUMO

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.


Assuntos
Moléculas de Adesão Celular/biossíntese , Dexametasona/farmacologia , Moléculas de Adesão Celular/antagonistas & inibidores , Sistema Livre de Células , Fibroblastos/imunologia , Fibroblastos/patologia , Fibrose/imunologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Mediadores da Inflamação/fisiologia , Interleucina-13/fisiologia , Interleucina-4/fisiologia , Pulmão/imunologia , Pulmão/patologia , Pele/imunologia , Pele/patologia , Distribuição Tecidual/imunologia , Fator de Crescimento Transformador beta1/fisiologia
13.
J Appl Microbiol ; 115(3): 711-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23826728

RESUMO

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.


Assuntos
Antifúngicos/farmacologia , Ácido Palmítico/farmacologia , Scedosporium/efeitos dos fármacos , Água/farmacologia , Sais/farmacologia , Sabões/química , Cloreto de Sódio/farmacologia , Água/química , Purificação da Água , Abrandamento da Água
14.
J Chem Phys ; 138(23): 234708, 2013 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-23802977

RESUMO

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.

15.
J Small Anim Pract ; 54(7): 377-80, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23614673

RESUMO

Mast cell tumours are one of the most common neoplasms in dogs. Mutations in the proto-oncogene c-kit, especially internal tandem duplications of exon 11, are considered to play a crucial role in mast cell tumourigenesis. In this report, two cases that suffered from multiple mast cell tumours containing an internal tandem duplication in the primary lesion but not in the secondary lesions are described. This finding indicates the existence of heterogenous c-kit gene mutations in each site of multiple mast cell tumours. Additionally, these results raise the possibility that the contribution of internal tandem duplications in the malignant transformation of mast cells is quite limited. It is proposed that, for clinicians, genetic analysis of several regions of multiple mast cell tumours is necessary for predicting prognosis and tumour response to KIT inhibitors.


Assuntos
Doenças do Cão/genética , Mastocitoma/veterinária , Terapia de Alvo Molecular/veterinária , Proteínas Proto-Oncogênicas c-kit/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-kit/metabolismo , Animais , Doenças do Cão/diagnóstico , Doenças do Cão/terapia , Cães , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Predisposição Genética para Doença , Masculino , Mastócitos , Mastocitoma/diagnóstico , Mastocitoma/genética , Mastocitoma/terapia , Mutação/genética , Prognóstico , Proteínas Proto-Oncogênicas c-kit/genética
17.
J Leukoc Biol ; 93(2): 245-50, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23125456

RESUMO

Mastocytosis is a disease accompanied by the abnormal expansion and accumulation of mast cells. Although the D816V mutation is detected in most cases of systemic mastocytosis, the mutation is rarely observed in other forms of mastocytosis, such as cutaneous mastocytosis and mast cell leukemia/sarcoma, for which the mechanism of tumorigenesis remains unknown. In this study, we demonstrated a novel mechanism of mast cell tumorigenesis via SCF autocrine/paracrine release. SCF was highly expressed in a WT KIT-expressing HRMC line, contributing to the phosphorylation of KIT. Neutralization of external SCF using a neutralizing antibody or suppression of SCF production by RNA interference inhibited the growth of HRMC cells, indicating the essential role of SCF in cell proliferation. To the best of our knowledge, this is the first report to determine the significant contribution of SCF autoproduction to neoplastic proliferation of mast cells. These results indicate the possibility that targeting SCF production may become a novel treatment for mast cell malignancies.


Assuntos
Comunicação Autócrina , Transformação Celular Neoplásica/metabolismo , Mastócitos/metabolismo , Mastócitos/patologia , Mastocitose/metabolismo , Comunicação Parácrina , Fator de Células-Tronco/metabolismo , Western Blotting , Linhagem Celular , Proliferação de Células , Transformação Celular Neoplásica/patologia , Citometria de Fluxo , Humanos , Mastocitose/patologia , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Allergy ; 67(10): 1241-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22845063

RESUMO

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.


Assuntos
Mastócitos/imunologia , Receptores de IgE/imunologia , Quinases da Família src/metabolismo , Adulto , Degranulação Celular/imunologia , Células Cultivadas , Regulação para Baixo , Humanos , Receptores de IgE/metabolismo , Transdução de Sinais
19.
Transplant Proc ; 44(3): 680-3, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22483467

RESUMO

OBJECTIVES: We expect that if chronic renal failure (CRF) is improved after renal transplantation (RTx), dialysis osteopathy bone lesions would also recover to normal. Nevertheless, it is controversial whether bone lesions really improve after RTx. In this study, we evaluated whether pathological dialysis osteopathy improved after RTx. MATERIALS AND METHODS: The 84 patients who had undergone living related RTx had also undergone a bone biopsy (Bx) since January 2004, including 13 (16.0%) with a diagnosis of aplastic osteopathy. They included 7 men and 6 women. The average hemodialysis (HD) period was 40.3 months. The immunosuppression was tacrolimus (FK); mycophenalate mofetil (MMF) and steroid. We examined Ca, P, intact-PTH (i-PTH), metabolic bone markers, and bone density (DXA) before and 1 year after RTx. In addition, a Bx was performed after having osteal labeling twice before Bx. In addition 2 cases (15.3%) also underwent a Bx after RTx. RESULTS: All cases survive with well functioning renal grafts. The mean levels of Ca and P before RTx were 8.7 mg/mL and 6.6 mg/dL, respectively. The mean i-PTH level was 137.8 pg/mL before RTx and of alkaline phosphatase (ALP) was 202.1 U/L before RTx. The total density and % age match of DXA before RTx averaged 398.7 mg/ccm and 96.7%, respectively. The mean bone volume fraction (BV/TV: Bone Volume/Tissue Volume) before RTx was 17.2%. The mean osteoid volume (OV/TV) before RTx was 2.7%. The mean fibrosis volume (Fb.V/TV) before RTx was 0%. The mean bone formation rate (BFR/BV) before RTx was 2.1 %/y. Two cases were also pathologically diagnosed as renal osteodystrophy at 1 year after RTx: 1 case was mixed type, and another was osteomalacia, which was accompanied by a lumbar compression fracture (Fx) during the clinical course. CONCLUSIONS: Bone metabolism in patients with aplastic ROD histologically improved at 1 year after RTx, presumably due to good renal transplant function. However, it is unknown whether both hypophosphatemia and decrease of FGF-23 improved bone However, patients with aplastic ROD were not completely normalized histologically at 1 year after RTx.


Assuntos
Doenças Ósseas/patologia , Transplante de Rim , Adulto , Feminino , Fator de Crescimento de Fibroblastos 23 , Humanos , Imunossupressores/administração & dosagem , Masculino , Pessoa de Meia-Idade , Diálise Renal , Resultado do Tratamento
20.
J Chem Phys ; 136(3): 034702, 2012 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-22280772

RESUMO

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.


Assuntos
Monóxido de Carbono/química , Ferro/química , Teoria Quântica , Espectrometria por Raios X
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