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1.
Materials (Basel) ; 16(20)2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37895636

RESUMEN

Dye-sensitized solar cells (DSSCs) have been one of the most promising technologies to convert sunlight into electricity repeatedly based on the mechanism that dyes inject/accept electron into the metal oxides/from redox mediator. Specifically, N719 ([RuL2(NCS)2], L: 4,4'-dicarboxy-2,2'-bipyridine), immobilized on TiO2 through the interaction between its ligands (-COO- and -NCS) and the oxygen on the TiO2 surface, has been used as a conventional DSSC dye with high voltage. Nevertheless, -NCS ligands have been removed from Ru2+ in N719 due to UV irradiation and exchanged with H2O or OH- in electrolyte, resulting in voltage drop. In this work, we developed the first DSSC using the N719-adsorbed Eggshell (ESM)-TiO2 composite to maintain the immobilization of N719 on TiO2 through electrostatic interaction between the protein of ESM and N719. The DSSC using the composite maintained the voltage even after 12 h light irradiation, although the voltage of DSSC without ESM dropped drastically. It means that the ESM contributed to stable photovoltaic performances of DSSCs through the protection of NCS ligands of N719.

2.
Pediatr Infect Dis J ; 42(12): 1041-1044, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37725804

RESUMEN

BACKGROUND: Yersinia infection is known to present with Kawasaki disease (KD)-like symptoms although differentiating the 2 has been a challenge. The present study aimed to describe the clinical characteristics and prevalence of Yersinia infection presenting with KD-like symptoms. METHODS: The present, prospective, multicenter study enrolled patients who received a diagnosis of KD between January 2021 and January 2022 at 2 hospitals in Tokyo. Stool samples were collected within 3 days of the start of KD treatment, and cultures were performed for Yersinia . Clinical history and symptoms suggestive of Yersinia infection were also evaluated. RESULTS: During the study period, 141 KD patients were screened and 117 patients with evaluable stool samples were registered. Only 1 patient was positive for Yersinia pseudotuberculosis , which was detected from both stool and blood cultures. The patient was refractory to KD treatment but improved after initiation of appropriate antibiotic therapy. CONCLUSIONS: Routine screening for Yersinia is not appropriate for patients with KD and should be limited to certain patients in high-risk areas and those who are refractory to the standard KD treatment.


Asunto(s)
Síndrome Mucocutáneo Linfonodular , Yersiniosis , Infecciones por Yersinia pseudotuberculosis , Yersinia pseudotuberculosis , Humanos , Síndrome Mucocutáneo Linfonodular/complicaciones , Síndrome Mucocutáneo Linfonodular/diagnóstico , Síndrome Mucocutáneo Linfonodular/epidemiología , Infecciones por Yersinia pseudotuberculosis/complicaciones , Infecciones por Yersinia pseudotuberculosis/diagnóstico , Infecciones por Yersinia pseudotuberculosis/epidemiología , Estudios Prospectivos , Yersiniosis/complicaciones , Yersiniosis/epidemiología
3.
Part Fibre Toxicol ; 20(1): 6, 2023 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-36797786

RESUMEN

BACKGROUND: A recent epidemiological study showed that air pollution is closely involved in the prognosis of ischemic stroke. We and others have reported that microglial activation in ischemic stroke plays an important role in neuronal damage. In this study, we investigated the effects of urban aerosol exposure on neuroinflammation and the prognosis of ischemic stroke using a mouse photothrombotic model. RESULTS: When mice were intranasally exposed to CRM28, urban aerosols collected in Beijing, China, for 7 days, microglial activation was observed in the olfactory bulb and cerebral cortex. Mice exposed to CRM28 showed increased microglial activity and exacerbation of movement disorder after ischemic stroke induction. Administration of core particles stripped of attached chemicals from CRM28 by washing showed less microglial activation and suppression of movement disorder compared with CRM28-treated groups. CRM28 exposure did not affect the prognosis of ischemic stroke in null mice for aryl hydrocarbon receptor, a polycyclic aromatic hydrocarbon (PAH) receptor. Exposure to PM2.5 collected at Yokohama, Japan also exacerbated movement disorder after ischemic stroke. CONCLUSION: Particle matter in the air is involved in neuroinflammation and aggravation of the prognosis of ischemic stroke; furthermore, PAHs in the particle matter could be responsible for the prognosis exacerbation.


Asunto(s)
Contaminantes Atmosféricos , Accidente Cerebrovascular Isquémico , Trastornos del Movimiento , Hidrocarburos Policíclicos Aromáticos , Animales , Ratones , Material Particulado/toxicidad , Material Particulado/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Enfermedades Neuroinflamatorias , China , Ratones Noqueados , Contaminantes Atmosféricos/toxicidad , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente
4.
Membranes (Basel) ; 13(1)2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36676922

RESUMEN

Recently, polymer electrolytes have been developed for high-performance and eco-friendly fuel cells. Among the candidates, eggshell membrane (ESM) has been promising because of its abundance to assemble various energy devices with low cost and its absorption ability of organic materials. In this work, we investigated fuel cells that included ESM-absorbing xanthene-, triphenylmethane-, and azo-type tar dye, which contained abundant hydrophilic groups, as polymer electrolytes. We found out two points: (1) that the fuel cells that included ESM-absorbing xanthene-type dye generated the highest I-V performance, and (2) the basic molecular structures of the tar dyes determined the correlation of the maximum power and proton conductivities.

5.
Chem Res Toxicol ; 35(12): 2241-2251, 2022 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-36399157

RESUMEN

Benzo[a]pyrene (BaP) is known to form DNA adduct following metabolic activation, which causes phosphorylation of histone H2AX (γ-H2AX). Recent studies have shown that histone deacetylase (HDAC) inhibitors enhanced BaP-induced CYP1A1 gene expression. In this study, we examined the relationship between the HDAC inhibitor-augmented metabolic activation and BaP-induced γ-H2AX. Sodium butyrate (SB), a typical HDAC inhibitor, enhanced BaP-induced γ-H2AX. The enhanced DNA damage was further confirmed by biased sinusoidal field gel electrophoresis, which detects DNA double-strand breaks. SB remarkably augmented BaP-induced CYP1A1 gene expression, and CYP1A1-overexpressing cells showed elevated generation of γ-H2AX. Furthermore, SB enhanced intracellular oxidation after treatment with BaP. These results suggested that SB-induced CYP1A1 upregulation facilitated BaP metabolism, which might result in excess DNA adducts or oxidative DNA damages, leading to augmentation of γ-H2AX.


Asunto(s)
Benzo(a)pireno , Citocromo P-450 CYP1A1 , Benzo(a)pireno/toxicidad , Benzo(a)pireno/metabolismo , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Inhibidores de Histona Desacetilasas , Aductos de ADN , Ácido Butírico
6.
ACS Omega ; 7(15): 12637-12642, 2022 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-35474842

RESUMEN

Polymer electrolyte membrane fuel cells have recently attracted considerable attention as sustainable and eco-friendly electricity generation devices from the viewpoint of carbon neutrality. This study focuses on new discoveries related to the application of eggshell membranes to polymer electrolytes in the development of cheaper, more eco-friendly fuel cells. We observed the electricity generation of the fuel cells using an eggshell membrane as a proton-conductive material and a general carbonic acid aqueous solution. This new fuel cell will contribute to the continued improvement of available fuel cells at lower costs.

7.
Epilepsia ; 63(7): 1704-1713, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35485955

RESUMEN

OBJECTIVE: This study was undertaken to evaluate the efficacy, safety, and economic impact of diazepam suppositories with as-needed acetaminophen in comparison with as-needed acetaminophen alone for prevention of seizure recurrence during the same fever episode in suspected pediatric simple febrile seizures (SFS). METHODS: This single-center, prospective, observational study was conducted from July 29, 2019 to February 15, 2021 at a children's hospital. Children aged 6 months to 60 months presenting to the emergency department with suspected SFS were included. Participants receiving both diazepam suppositories and as-needed acetaminophen were compared with those receiving as-needed acetaminophen alone. The primary outcome was seizure recurrence during the same fever episode. The secondary outcomes included the incidence of central nervous system (CNS) pathologies, adverse events, and medical costs. RESULTS: Of the 316 participants, 228 (72.2%) had their first febrile seizure. Diazepam (.3-.5 mg/kg for up to two doses) was administered to 88 of 316 patients (27.8%). The outcomes were available for 306 patients. The recurrence rate was 3.5% (3/85) in the patients receiving diazepam with as-needed acetaminophen and 12.2% (27/221) in the patients receiving as-needed acetaminophen alone (relative risk = .29, 95% confidence interval [CI] = .09-.93, p = .03). The adjusted odds ratio of diazepam administration against recurrence was .23 (95% CI = .07-.78, p = .02). None of the patients had a CNS pathology. No severe adverse events occurred, although mild ataxia was observed significantly more often in the patients receiving diazepam and as-needed acetaminophen (29.4% vs. 18.7%, p = .04). The median medical cost was US $199 (interquartile range [IQR] = 86-244) for the group receiving both medications and US $202 (IQR = 114-242) for the group receiving as-needed acetaminophen alone. SIGNIFICANCE: Compared with as-needed acetaminophen alone, diazepam with as-needed acetaminophen may reduce seizure recurrence more during the same fever episode without severe adverse events or additional costs in children with suspected SFS.


Asunto(s)
Convulsiones Febriles , Acetaminofén/efectos adversos , Niño , Diazepam/efectos adversos , Fiebre/inducido químicamente , Fiebre/prevención & control , Humanos , Lactante , Estudios Prospectivos , Recurrencia , Convulsiones Febriles/inducido químicamente , Convulsiones Febriles/prevención & control , Supositorios
8.
J Imaging ; 7(8)2021 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-34460770

RESUMEN

SNS providers are known to carry out the recompression and resizing of uploaded images, but most conventional methods for detecting fake images/tampered images are not robust enough against such operations. In this paper, we propose a novel method for detecting fake images, including distortion caused by image operations such as image compression and resizing. We select a robust hashing method, which retrieves images similar to a query image, for fake-image/tampered-image detection, and hash values extracted from both reference and query images are used to robustly detect fake-images for the first time. If there is an original hash code from a reference image for comparison, the proposed method can more robustly detect fake images than conventional methods. One of the practical applications of this method is to monitor images, including synthetic ones sold by a company. In experiments, the proposed fake-image detection is demonstrated to outperform state-of-the-art methods under the use of various datasets including fake images generated with GANs.

9.
Cells ; 10(4)2021 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-33804845

RESUMEN

Microglia are activated after ischemic stroke and induce neuroinflammation. The expression of the aryl hydrocarbon receptor (AhR) has recently been reported to elicit cytokine expression. We previously reported that microglial activation mediates ischemic edema progression. Thus, the purpose of this study was to examine the role of AhR in inflammation and edema after ischemia using a mouse middle cerebral artery occlusion (MCAO) model. MCAO upregulated AhR expression in microglia during ischemia. MCAO increased the expression of tumor necrosis factor α (TNFα) and then induced edema progression, and worsened the modified neurological severity scores, with these being suppressed by administration of an AhR antagonist, CH223191. In THP-1 macrophages, the NADPH oxidase (NOX) subunit p47phox was significantly increased by AhR ligands, especially under inflammatory conditions. Suppression of NOX activity by apocynin or elimination of superoxide by superoxide dismutase decreased TNFα expression, which was induced by the AhR ligand. AhR ligands also elicited p47phox expression in mouse primary microglia. Thus, p47phox may be important in oxidative stress and subsequent inflammation. In MCAO model mice, P47phox expression was upregulated in microglia by ischemia. Lipid peroxidation induced by MCAO was suppressed by CH223191. Taken together, these findings suggest that AhR in the microglia is involved in neuroinflammation and subsequent edema, after MCAO via p47phox expression upregulation and oxidative stress.


Asunto(s)
Edema Encefálico/etiología , Edema Encefálico/metabolismo , Encefalitis/etiología , Encefalitis/metabolismo , Accidente Cerebrovascular Isquémico/complicaciones , Microglía/metabolismo , Receptores de Hidrocarburo de Aril/metabolismo , Animales , Edema Encefálico/patología , Lesiones Encefálicas/etiología , Citocromo P-450 CYP1A1/metabolismo , Citocinas/metabolismo , Encefalitis/patología , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Infarto de la Arteria Cerebral Media/complicaciones , Ligandos , Macrófagos/metabolismo , Masculino , Ratones Endogámicos ICR , NADPH Oxidasas/genética , NADPH Oxidasas/metabolismo , Estrés Oxidativo , Regiones Promotoras Genéticas/genética , Subunidades de Proteína/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Receptores de Hidrocarburo de Aril/antagonistas & inhibidores , Células THP-1 , Factor de Necrosis Tumoral alfa/metabolismo , Regulación hacia Arriba
10.
Materials (Basel) ; 13(12)2020 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-32580332

RESUMEN

The Na0.5Co0.9Cu0.1O2 thick film with the same thermoelectric performance as a Na0.5CoO2 bulk was formed on an alumina substrate by the screen-printing process. The power factor exceeded 0.3 mW/K2m, with the resistivity of 3.8 mΩcm and the thermopower of 108 µV/K. The thick film without any cracks strongly adhered to the substrate. The high-quality thick film had been realized through the carefully designed and improved process, mixing NaCl to promote the anisotropic sintering of Na0.5Co0.9Cu0.1O2, inserting a CuO interlayer to adhere the film and substrate, and Co-Cu substituting Cu for Co to control the sintering temperature.

11.
Acta Crystallogr F Struct Biol Commun ; 76(Pt 3): 130-137, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32133998

RESUMEN

TRPV1, a member of the transient receptor potential (TRP) channels family, has been found to be involved in redox sensing. The crystal structure of the human TRPV1 ankyrin-repeat domain (TRPV1-ARD) was determined at 4.5 Šresolution under nonreducing conditions. This is the first report of the crystal structure of a ligand-free form of TRPV1-ARD and in particular of the human homologue. The structure showed a unique conformation in finger loop 3 near Cys258, which is most likely to be involved in inter-subunit disulfide-bond formation. Also, in human TRPV1-ARD it was possible for solvent to access Cys258. This structural feature might be related to the high sensitivity of human TRPV1 to oxidants. ESI-MS revealed that Cys258 did not form an S-OH functionality even under nonreducing conditions.


Asunto(s)
Repetición de Anquirina/fisiología , Canales Catiónicos TRPV/química , Canales Catiónicos TRPV/genética , Ancirinas/química , Ancirinas/genética , Ancirinas/metabolismo , Cristalización/métodos , Humanos , Estructura Secundaria de Proteína , Canales Catiónicos TRPV/metabolismo
12.
J Infect Chemother ; 26(5): 510-512, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31982291

RESUMEN

Eikenella corrodens is a facultatively anaerobic gram-negative rod bacterium in the oropharynx and respiratory tract. It is a member of HACEK (Haemophilus spp., Aggregatibacter spp., Cardiobacterium hominis, E. corrodens, and Kingella kingae) group commonly associated with endocarditis and craniofacial infections. It is usually susceptible to penicillin, second and third-generation cephalosporins, and carbapenem, but has variable susceptibility to first-generation cephalosporin. We herein provide a description of the first case of pediatric acute dacryocystitis caused by E. corrodens. The patient did not respond to oral cephalexin and required surgical drainage followed by intravenous cefotaxime. Also provided is a brief review of the current literature.


Asunto(s)
Dacriocistitis/diagnóstico , Dacriocistitis/microbiología , Eikenella corrodens/patogenicidad , Infecciones por Bacterias Gramnegativas/microbiología , Enfermedad Aguda , Aggregatibacter , Antibacterianos/administración & dosificación , Cardiobacterium , Cefotaxima/administración & dosificación , Cefalexina/administración & dosificación , Preescolar , Dacriocistitis/tratamiento farmacológico , Vías de Administración de Medicamentos , Eikenella corrodens/aislamiento & purificación , Femenino , Infecciones por Bacterias Gramnegativas/diagnóstico , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Haemophilus , Humanos , Kingella , Pruebas de Sensibilidad Microbiana , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
13.
J Epidemiol ; 29(1): 33-37, 2019 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-29887543

RESUMEN

BACKGROUND: Although lower household economic status is known to be a risk factor for obesity among school-age children, such an association among toddlers remains unclear. The present study investigated the association between household economic status and obesity in toddlers. DESIGN: We conducted a cross-sectional study of children aged 4 years attending daycare centers in Japan. Information on subjective household economic status ["affluent", "neither", "less affluent", or "non-affluent"] was collected via questionnaire from the children's guardians in 2015. Based on measured values of height and weight, obesity was defined using the International Obesity Task Force cut-offs of overweight (BMI ≥17.47 for boys and ≥17.19 for girls). We used the logistic regression model to investigate the association between household economic status and obesity. RESULTS: Among 1,848 respondents, the prevalence of obesity was 6.8%. Non-affluent household economic status was associated with a significantly higher probability of obesity in toddlers; the multivariate adjusted odds ratio for "non-affluent" households was 2.31 (95% confidence interval, 1.23-4.33) compared with "affluent" households. CONCLUSION: Perception of non-affluent economic status by the guardian was associated with a higher probability of toddler obesity. This result suggests that non-affluent household economic status is associated with obesity in toddlers.


Asunto(s)
Estatus Económico , Composición Familiar , Obesidad Infantil/epidemiología , Guarderías Infantiles , Preescolar , Estudios Transversales , Femenino , Humanos , Japón/epidemiología , Masculino , Factores de Riesgo
14.
Nurse Educ Today ; 65: 41-45, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29525485

RESUMEN

BACKGROUND: Exposure of nursing students to foreign residents may improve cultural understanding. Nursing students are expected to have differing rates of contact with foreign residents, depending on how many foreign residents live in their municipality where they study in. Those in areas densely populated by foreign residents are more likely to encounter foreigners, and to have favorable views of them than students in areas with sparser foreign-resident populations. As of 2015, 2.23 million foreign residents lived in Japan, equaling 1.76% of the population; however, Japan still has fewer foreign-born residents compared to other countries. Therefore, interest in Medical Health Care for Foreign Residents (MHCFR) may be greater in students in ethnically diverse areas. While nursing students may have different levels of recognition of foreign nationals as potential clients and interest in MHCFR, no research validates this assumption. OBJECTIVES: This study aimed to clarify the association between proximity to foreign nationals and interest in MHCFR among Japanese nursing students. The secondary purpose was to describe knowledge and interest regarding MHCFR among students. To elucidate these topics, education and development of human resources in MHCFR should be considered. RESEARCH DESIGN AND METHOD: The study design was cross-sectional. A self-administered questionnaire survey was conducted with 143 nursing students. RESULTS: Most students understood the likelihood of providing nursing care to foreigners; however, knowledge and interest were low, regardless of whether lectures on MHCFR were provided. Knowledge of MHCFR, recognition of providing care to foreign nationals, and level of contact experiences with foreign nationals were significantly associated with students' level of interest in MHCFR. DISCUSSION: Nursing students in ethnically diverse areas tend to show greater interest in MHCFR in Japan. To foster global health perspectives, including MHCFR, in nursing students studying in ethnically diverse areas, contact experiences with foreigners and acceptance of international students by universities might be effective.


Asunto(s)
Bachillerato en Enfermería/métodos , Emigrantes e Inmigrantes/estadística & datos numéricos , Estudiantes de Enfermería/psicología , Adulto , Estudios Transversales , Bachillerato en Enfermería/estadística & datos numéricos , Bachillerato en Enfermería/tendencias , Femenino , Humanos , Japón/etnología , Masculino , Estudiantes de Enfermería/estadística & datos numéricos , Encuestas y Cuestionarios
15.
BMC Res Notes ; 11(1): 116, 2018 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-29426362

RESUMEN

OBJECTIVE: This study aimed to evaluate clinically the effect of a novel dentifrice containing three kinds of bactericidal ingredients on periodontal disease. RESULTS: This was a single-arm, prospective clinical study that enrolled patients with periodontitis undergoing supportive periodontal therapy. Periodontal examination, microbiological testing of saliva samples, and evaluation of inflammatory markers (IL-1ß, IL-6, IL-8, TNF-α) in gingival crevicular fluid were performed. After 4 weeks of the use of test dentifrice, these parameters were re-evaluated. The use of dentifrice was also subjectively evaluated by clinicians and participants. Among 30 participants, there were significant improvements in the periodontal and microbiological parameters, and the level of interleukin-1ß in the gingival crevicular fluid, following the use of the test dentifrice. In clinicians' subjective evaluation of the overall usefulness of the dentifrice, 'mild' and 'moderate' improvement accounted for 83% of the total responses. In the participants' subjective evaluation, the majority indicated their experience of the use as favorable. Within the limitations of this study, it is suggested that the progression of periodontal disease during the supportive periodontal therapy can be prevented by the use of the test dentifrice. Trial registration UMIN Clinical Trials Registry (UMIN-CTR) 000023175. Date of formal registration: July 14, 2016 ( https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000026716 ).


Asunto(s)
Antibacterianos/farmacología , Dentífricos/uso terapéutico , Líquido del Surco Gingival/inmunología , Periodontitis/diagnóstico , Periodontitis/tratamiento farmacológico , Adulto , Anciano , Antibacterianos/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Resultado del Tratamiento
16.
Biochem Biophys Res Commun ; 496(2): 582-587, 2018 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-29353043

RESUMEN

Brain edema is a severe complication that accompanies ischemic stroke. Increasing evidence shows that inflammatory cytokines impair tight junctions of the blood-brain barrier, suggesting the involvement of microglia in brain edema. In this study, we examined the role of microglia in the progression of ischemic brain edema using mice with permanent middle cerebral artery occlusion. The intensity of T2-weighted imaging (T2WI) in the cerebral cortex and the striatum was elevated 3 h after occlusion and spread to peripheral regions of the ischemic hemisphere. Merged images of 2,3,5-triphenyl tetrazolium chloride staining and T2WI revealed the exact vasogenic edema region, which spread from the ischemic core to outside the ischemic region. Microglia were strongly activated in the ischemic region 3 h after occlusion and, notably, activated microglia were observed in the non-ischemic region 24 h after occlusion. Pretreatment with minocycline, an inhibitor of microglial activation clearly suppressed not only vasogenic edema but also infarct formation. We demonstrated in this study that vasogenic edema spreads from the ischemic core to the peripheral region, which can be elicited, at least in part, by microglial activation induced by ischemia.


Asunto(s)
Edema Encefálico/etiología , Encéfalo/patología , Infarto de la Arteria Cerebral Media/complicaciones , Microglía/patología , Animales , Edema Encefálico/patología , Progresión de la Enfermedad , Infarto de la Arteria Cerebral Media/patología , Masculino , Ratones Endogámicos ICR , Agua/análisis
18.
Sci Rep ; 7(1): 6268, 2017 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-28740157

RESUMEN

Several studies have shown that docosahexaenoic acid (DHA) attenuates epileptic seizures; however, the molecular mechanism by which it achieves this effect is still largely unknown. DHA stimulates the retinoid X receptor, which reportedly regulates the expression of cytochrome P450 aromatase (P450arom). This study aimed to clarify how DHA suppresses seizures, focusing on the regulation of 17ß-estradiol synthesis in the brain. Dietary supplementation with DHA increased not only the expression of P450arom, but also 17ß-estradiol in the cerebral cortex. While DHA did not affect the duration or scores of the seizures induced by pentylenetetrazole, DHA significantly prolonged the seizure latency. A P450arom inhibitor, letrozole, reduced 17ß-estradiol levels and completely suppressed the elongation of seizure latency elicited by DHA. These results suggest that DHA delays the onset of seizures by promoting the synthesis of 17ß-estradiol in the brain. DHA upregulated the expression of anti-oxidative enzymes in the cerebral cortex. The oxidation in the cerebral cortex induced by pentylenetetrazole was significantly attenuated by DHA, and letrozole completely inhibited this suppressive action. Thus, the anti-oxidative effects of 17ß-estradiol may be involved in the prevention of seizures mediated by DHA. This study revealed that 17ß-estradiol in the brain mediated the physiological actions of DHA.


Asunto(s)
Encéfalo/efectos de los fármacos , Suplementos Dietéticos , Ácidos Docosahexaenoicos/farmacología , Estradiol/biosíntesis , Letrozol/farmacología , Pentilenotetrazol/toxicidad , Convulsiones/prevención & control , Animales , Inhibidores de la Aromatasa/farmacología , Encéfalo/metabolismo , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Masculino , Ratones , Ratones Endogámicos ICR , Convulsiones/inducido químicamente , Convulsiones/metabolismo
19.
Environ Health Prev Med ; 21(6): 554-562, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27738877

RESUMEN

OBJECTIVE: The aim of this study was to investigate the therapeutic effects of a Sasa veitchii leaf extract (SE) on carbon tetrachloride (CCl4)-induced hepato- and nephrotoxicity. METHODS: Seven-week-old male ddy mice were orally administered SE or saline for seven days. Twenty-four hours after the last SE or saline administration, the mice were intraperitoneally injected with 3 g/kg CCl4 or olive oil. The mice from each group were euthanized and bled for plasma analysis 24 h after the CCl4/olive oil injection. RESULTS: We found that pretreatment with SE completely abolished the CCl4-induced mortality in the mice after 24 h. The mice pretreated with SE exhibited significantly decreased levels of functional markers, and reduced histological damage in both the liver and the kidney. Furthermore, we found that the SE pretreatment decreased lipid peroxidation and calcium levels in the liver. Although SE could not induce the free radical-scavenging metallothioneins, the plasma biological antioxidant power was significantly increased in the mice pretreated with SE. CONCLUSION: Our findings demonstrate that prophylactic treatment with SE protects mice from CCl4-induced lethal toxicity by decreasing oxidative stress in the liver and kidney, presumably by increasing biological antioxidant power.


Asunto(s)
Tetracloruro de Carbono/toxicidad , Riñón/efectos de los fármacos , Hígado/efectos de los fármacos , Extractos Vegetales/farmacología , Sustancias Protectoras/farmacología , Sasa/química , Animales , Masculino , Ratones , Estrés Oxidativo/efectos de los fármacos , Hojas de la Planta/química
20.
J Org Chem ; 80(19): 9480-94, 2015 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-26348544

RESUMEN

A protocol for the direct synthesis of azepines using a hafnium(III)-catalyzed [6 + 1] annulation of N-tethered ynenitriles with Reformatsky reagents is reported. A broad range of 3-amino-2,7-dihydro-1H-azepine-4-carboxylates 4aa-4he were obtained in high yields and with excellent functional group tolerance. The copper-mediated reactions of isolable Blaise intermediates (enamino esters 3), uniquely underwent 5-endo cyclization to afford the ß-2,5-dihydropyrrolyl α,ß-unsaturated esters 5aa-5fc, which exhibit anticancer activity.

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