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1.
J Phys Chem A ; 128(7): 1241-1249, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38324399

RESUMO

The recent implementation of attosecond and few-femtosecond X-ray pump/X-ray probe schemes in large-scale free-electron laser facilities has opened the way to visualize fast nuclear dynamics in molecules with unprecedented temporal and spatial resolution. Here, we present the results of theoretical calculations showing how polarization-averaged molecular-frame photoelectron angular distributions (PA-MFPADs) can be used to visualize the dynamics of hydrogen migration in methanol, ethanol, propanol, and isopropyl alcohol dications generated by X-ray irradiation of the corresponding neutral species. We show that changes in the PA-MFPADs with the pump-probe delay as a result of intramolecular photoelectron diffraction carry information on the dynamics of hydrogen migration in real space. Although visualization of this dynamics is more straightforward in the smaller systems, methanol and ethanol, one can still recognize the signature of that motion in propanol and isopropyl alcohol and assign a tentative path to it. A possible pathway for a corresponding experiment requires an angularly resolved detection of photoelectrons in coincidence with molecular fragment ions used to define a molecular frame of reference. Such studies have become, in principle, possible since the first XFELs with sufficiently high repetition rates have emerged. To further support our findings, we provide experimental evidence of H migration in ethanol-OD from ion-ion coincidence measurements performed with synchrotron radiation.

3.
Gene Ther ; 24(11): 706-716, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28820502

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a fatal disease with a median survival of 3-4 years after diagnosis. It is the most frequent form of a group of interstitial pneumonias of unknown etiology. Current available therapies prevent deterioration of lung function but no therapy has shown to improve survival. Periostin is a matricellular protein of the fasciclin 1 family. There is increased deposition of periostin in lung fibrotic tissues. Here we evaluated whether small interfering RNA or antisense oligonucleotide against periostin inhibits lung fibrosis by direct administration into the lung by intranasal route. Pulmonary fibrosis was induced with bleomycin and RNA therapeutics was administered during both acute and chronic phases of the disease. The levels of periostin and transforming growth factor-ß1 in airway fluid and lung tissue, the deposition of collagen in lung tissue and the lung fibrosis score were significantly reduced in mice treated with siRNA and antisense against periostin compared to control mice. These findings suggest that direct administration of siRNA or antisense oligonucleotides against periostin into the lungs is a promising alternative therapeutic approach for the management of pulmonary fibrosis.


Assuntos
Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/fisiologia , Fibrose Pulmonar/terapia , Administração Intranasal/métodos , Animais , Bleomicina/farmacologia , Colágeno/análise , Feminino , Fibroblastos/metabolismo , Fibrose , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/terapia , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Oligonucleotídeos , Oligonucleotídeos Antissenso/metabolismo , Fibrose Pulmonar/genética , Fibrose Pulmonar/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , RNA Interferente Pequeno/farmacologia , Fator de Crescimento Transformador beta/análise
4.
J Periodontal Res ; 51(5): 613-21, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26667496

RESUMO

BACKGROUND AND OBJECTIVE: Previous studies have shown that cigarette smoke (CS) and periodontal pathogens could alter wound healing responses of gingival epithelial cells. To elucidate molecular mechanisms leading to these epithelial changes, we studied the signaling pathway involved in the modulation of cell migration by CS condensate (CSC) and the infection by a prominent periodontal pathogen, Porphyromonas gingivalis. MATERIAL AND METHODS: Human gingival epithelial cells (Ca9-22) were treated with CSC or vehicle control for 24 h. Activation of mitogen-activated protein kinases (MAPK) in cells with or without infection by P. gingivalis was assessed by polymerase chain reaction array and immunoblotting using phospho-specific antibodies. Cell migration was assessed using in vitro wound closure model, and specific pharmacologic inhibitors of MAPK pathways were used to characterize further the extent of involvement of the MAPK pathways. RESULTS: Polymerase chain reaction array showed that gene expression of several members of the MAPK, particularly p38 and JNK, was upregulated more than twofold in Ca9-22 cells stimulated with 10 µg/mL CSC. Coincubation with P. gingivalis induced a different pattern of gene expression for MAPK pathways, but it did not suppress the MAPK-related genes upregulated by CSC. A significant phosphorylation of ERK1/2 and p38 was observed in cells stimulated with 10 µg/mL CSC (p < 0.05), whereas coincubation with a higher concentration of CSC (250 µg/mL) evoked no such activation. P. gingivalis infection resulted in a tendency to reduce the phosphorylation of ERK1/2 and p38, which had been enhanced by stimulation with 10 µg/mL CSC. Incubation with ERK1/2 and p38 inhibitors significantly reduced the wound closure of CSC-stimulated cells, by approximately 43% and 46%, respectively (p < 0.05). CONCLUSION: CSC exerts effects on the migration of human gingival epithelial cells through the activation of the MAPK ERK1/2 and p38 signaling pathways. P. gingivalis infection attenuates the CSC-induced migration at least partly by suppressing the phosphorylation of ERK1/2 and p38, but other pathways are likely to be involved in this modulatory process.


Assuntos
Movimento Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Gengiva/citologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Nicotiana , Porphyromonas gingivalis/fisiologia , Fumaça , Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , Células Epiteliais/microbiologia , Células Epiteliais/fisiologia , Regulação da Expressão Gênica , Gengiva/efeitos dos fármacos , Gengiva/microbiologia , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/farmacologia , Nicotina/efeitos adversos , Fosforilação , Porphyromonas gingivalis/patogenicidade , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima , Cicatrização , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
5.
J Chem Phys ; 144(8): 084904, 2016 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-26931723

RESUMO

Differential Scanning Calorimetry (DSC) and optical polarization microscopy of a mixture of the liquid crystalline material (N-(4-methoxybenzylidene)-4-butylaniline, MBBA) and a Fe-based room temperature ionic liquid 1-ethyl-3-methylimidazolium tetrachloroferrate ([Emim](+) [FeCl4](-), EMIF) indicate a decrease in the nematic-isotropic (N-I) phase transition temperature (T(NI)) with an increase in EMIF concentration, explained by a proposed model of Coulomb "screening" of MBBA quadrupoles by the EMIF ions along with ionic "self screening." DSC studies of EMIF-MBBA and pure EMIF and comparison with pure MBBA results show that the major transitions in pure EMIF have Arrhenius behaviour, but more importantly the previously found convex Arrhenius behaviour of the pristine MBBA [K. Dan et al., Europhys. Lett. 108, 36007 (2014)] becomes Arrhenius in the mixture, indicating a conversion of the entropic N-I activation barrier to an enthalpic one. In presence of EMIF, a drastic decrease in the intensity of out-of-plane distortions of benzene rings in MBBA is found from Fourier transform infrared spectroscopy, consistent with significant reduction in the conformational states of MBBA. This suppression of large amplitude motion is again consistent with a Coulomb screening and gives a molecular basis for the entropic-to-enthalpic conversion of the N-I activation barrier.

6.
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
7.
Br J Cancer ; 111(4): 799-806, 2014 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-25032734

RESUMO

BACKGROUND: Cisplatin and other anticancer drugs are important in the treatment of head and neck squamous cell carcinoma; however, some tumours develop drug resistance. If chemoresistance could be determined before treatment, unnecessary drug administration would be avoided. Here, we investigated chemoresistance factors by comprehensive analyses at the protein level. METHODS: Four human carcinoma cell lines were used: cisplatin-sensitive UM-SCC-23, UM-SCC-23-CDDPR with acquired cisplatin resistance, naturally cisplatin-resistant UM-SCC-81B, and UM-SCC-23/WR with acquired 5-fluorouracil resistance. Extracted proteins were labelled with iTRAQ and analysed by tandem mass spectrometry to identify resistance. Protein expression was confirmed by western blotting and functional analysis was carried out using siRNA. RESULTS: Thirteen multiple-drug resistance proteins were identified, as well as seven proteins with specific resistance to cisplatin, including α-enolase. Differential expression of these proteins in cisplatin-resistant and -sensitive cell lines was confirmed by western blotting. Functional analysis for α-enolase by siRNA showed that cisplatin sensitivity significantly was increased in UM-SCC-81B and slightly in UM-SCC-23-CDDPR but not in UM-SCC-23/WR cells. CONCLUSIONS: We identified proteins thought to mediate anticancer drug resistance using recent proteome technology and identified α-enolase as a true cisplatin chemoresistance factor. Such proteins could be used as biomarkers for anticancer agent resistance and as targets of cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Carcinoma de Células Escamosas/metabolismo , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Fluoruracila/farmacologia , Neoplasias de Cabeça e Pescoço/metabolismo , Proteoma/metabolismo , Carcinoma de Células Escamosas/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Fosfopiruvato Hidratase/genética , Fosfopiruvato Hidratase/metabolismo , RNA Interferente Pequeno/genética , Receptor Notch1/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço , Coloração e Rotulagem , Espectrometria de Massas em Tandem
8.
Eur J Neurol ; 21(6): 867-73, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24602238

RESUMO

BACKGROUND AND PURPOSE: Several studies have reported moyamoya syndrome associated with thyroid disease, and the mechanism involved in this relationship is unknown. This study aimed to clarify the involvement of thyroid antibodies and thyroid function in intracranial arterial stenosis. METHODS: The study included 30 patients <65 years of age with intracranial arterial steno-occlusion. Patients with definitive moyamoya disease were excluded. Thyroid function and thyroid antibody levels were evaluated. The steno-occlusive site and the presence of moyamoya vessels were evaluated using digital subtraction angiography. The characteristics of intracranial arterial lesions were compared between patients with and without elevated thyroid antibody levels, and between patients with increased thyroid function and those with normal thyroid function. RESULTS: Five patients had increased thyroid function and seven had elevated thyroid antibody levels. Four were diagnosed with Graves' disease, 13 with atherosclerotic intracranial stenosis, two with intracranial arterial dissection, one with vasculitis syndrome and 10 with intracranial stenosis of unknown cause. All patients with Graves' disease and patients with elevated antithyroid peroxidase antibody levels had steno-occlusion in the terminal portion of the internal carotid arteries, whereas most of the patients with normal thyroid function or without elevated thyroid antibody levels had stenosis in the middle cerebral arteries. CONCLUSIONS: In young and middle-aged patients, a lesion in the terminal portion of the internal carotid artery was associated with elevated thyroid antibody levels and increased thyroid function. Stenoses found in the terminal portion of the internal carotid artery and immune-mediated thyroid diseases may share a common background.


Assuntos
Autoanticorpos/sangue , Artéria Carótida Interna/patologia , Estenose das Carótidas/imunologia , Doença de Moyamoya/imunologia , Doenças da Glândula Tireoide/imunologia , Adulto , Estenose das Carótidas/sangue , Estenose das Carótidas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Moyamoya/sangue , Doença de Moyamoya/patologia , Doenças da Glândula Tireoide/sangue , Doenças da Glândula Tireoide/patologia
9.
Infection ; 42(4): 639-47, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24567233

RESUMO

INTRODUCTION: Micafungin (MCFG) is used for the prophylaxis of invasive fungal disease (IFD) after allogeneic hematopoietic stem cell transplantation (HSCT). However, the safety, efficacy, or optimal dosage/blood levels as prophylaxis is uncertain in pediatric HSCT-patients. METHODS: We prophylactically administered MCFG at 2 mg/kg once daily to 38 children and adolescents undergoing allogeneic HSCT. RESULTS: During MCFG prophylaxis, infusion reactions or adverse events (grades 2-5) related to MCFG use were not found in all the patients. Thus, MCFG prophylaxis was not discontinued and other antifungal agents were not added except for 2 patients in whom probable or possible IFDs developed (completion rate, 94.7 %). To elucidate the influence of HSCT-related complications/drugs on blood concentration of MCFG, we determined the plasma trough and peak levels in 13 and 10 among 38 patients, respectively. The mean trough and peak levels were 3.04 ± 1.21 µg/mL (569 samples) and 9.63 ± 3.62 µg/mL (44 samples), respectively. The peak levels were moderately correlated to the trough levels (R (2) = 0.466). In a patient, the trough level of MCFG transiently increased up to 10.21 µg/mL during hepatic dysfunction due to acute graft-versus-host disease. The MCFG trough levels strongly correlated with T-Bil value (R (2) = 0.894). There was no relationship between the trough levels of MCFG and the circulating concentrations of tacrolimus (R (2) = 0.040). Additionally, MCFG levels were not influenced by treatment with cyclophosphamide or corticosteroids. CONCLUSIONS: Prophylaxis with MCFG at 2 mg/kg once daily may be safe, tolerable, and feasible in pediatric HSCT-patients.


Assuntos
Antifúngicos/administração & dosagem , Quimioprevenção/métodos , Equinocandinas/administração & dosagem , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Lipopeptídeos/administração & dosagem , Micoses/prevenção & controle , Adolescente , Antifúngicos/efeitos adversos , Antifúngicos/farmacocinética , Quimioprevenção/efeitos adversos , Criança , Pré-Escolar , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Equinocandinas/efeitos adversos , Equinocandinas/farmacocinética , Feminino , Humanos , Lactente , Lipopeptídeos/efeitos adversos , Lipopeptídeos/farmacocinética , Masculino , Micafungina , Plasma/química
10.
Tech Coloproctol ; 18(7): 647-52, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24500723

RESUMO

BACKGROUND: We evaluated the efficacy and safety of superselective embolization with assistance of colonoscopy for acute colonic hemorrhage. METHODS: Of 92 cases of acute colonic hemorrhage requiring colonoscopic intervention, 11 (12 %) could not be successfully treated. Of these, 10 patients (9 men, mean age 65.5 years, range 39-75 years) underwent superselective embolization. Hemorrhage was caused by diverticular disease (n = 8), polypectomy (n = 1), and vascular malformation (n = 1). In all 10 cases, the radiopaque clips were placed at the bleeding point via colonoscopy. Microcatheters were used in all procedures, and embolization was performed at the level of the vasa recta leading to or near the clips with Gelfoam particles, microcoils, or both. RESULTS: Immediate hemostasis was achieved in all patients. In 6 of 10 patients (60 %), selective angiograms showed no active extravasation at the time of the procedure and the embolization was performed using clips as a landmark. In the remaining four patients, selective angiograms showed active extravasation from the vasa recta leading to the clips. The mean number of embolized vessels with no active extravasation and with active extravasation was 1.83 (range 1-3) and 1.25 (range 1-2), respectively. The mean duration of clinical follow-up was 11.6 months (range 1-29 months). One patient (10 %) bled from a different site than the treated site a month after embolization, but the bleeding ceased after endoscopic intervention. All the patients (100 %) were evaluated for objective evidence of ischemia by colonoscopy. Four of the 10 patients (40 %) were found endoscopically to have small areas of ischemia involving only the mucosa, but they remained asymptomatic. There was no bowel infarction or stricture. CONCLUSIONS: Colonoscopy-assisted superselective embolization may be a safe and useful procedure for acute colonic hemorrhage without active extravasation on angiogram.


Assuntos
Doenças do Colo/terapia , Colonoscopia/métodos , Embolização Terapêutica/métodos , Hemorragia Gastrointestinal/terapia , Doença Aguda , Adulto , Angiografia/métodos , Estudos de Coortes , Colectomia/métodos , Doenças do Colo/diagnóstico por imagem , Doenças do Colo/mortalidade , Feminino , Seguimentos , Hemorragia Gastrointestinal/diagnóstico por imagem , Hemorragia Gastrointestinal/mortalidade , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Segurança do Paciente , Recidiva , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Taxa de Sobrevida , Resultado do Tratamento
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