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4.
Chem Commun (Camb) ; 54(21): 2670-2673, 2018 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-29479617

RESUMEN

The amount of adsorbed Fe(iii) on BiVO4 particles, which is controlled by the pH and temperature of the reaction solution, strongly affects the photocatalytic performance of BiVO4 for Fe(iii) reduction. Quantum and solar-energy-conversion efficiencies of 38% and 0.65%, respectively, were achieved.

6.
Chem Commun (Camb) ; 53(31): 4378-4381, 2017 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-28378862

RESUMEN

Photoelectrochemical dimethoxylation of furan with methanol using a BiVO4/WO3 photoanode and Br+/Br- as a mediator was demonstrated with low applied potential. The faradaic efficiency for the dimethoxylation with a Et4NBF4 co-supporting electrolyte at +0.1 V vs. SHE was almost quantitative up to 99%.

7.
Skin Res Technol ; 22(1): 20-4, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25786330

RESUMEN

BACKGROUND/PURPOSE: Perceived age may be a better predictor of mortality rate than chronological age. We have demonstrated that perceived age was a significant biomarker for carotid atherosclerosis in Japanese. However, it remains to be determined which skin parameter is associated with atherosclerosis. The purpose of this study is to analyze the relationship between 10 facial skin-aging parameters and atherosclerosis in 169 middle-aged to elderly Japanese women who participated. METHODS: Facial photographs were taken under a shadowless lamp from three directions using a high-resolution digital camera. The digital images of each subject were analyzed using computer software and various parameters of skin aging such as pigmentation, wrinkles, and skin color were quantified. Carotid intima-media thickness (IMT) and brachial-ankle pulse wave velocity (baPWV) were measured as indices for atherosclerosis. RESULTS: Facial pigmentation showed a significant correlation with carotid IMT, even after correction for age (r = 0.13, P = 0.03), and with visceral fat area. Stepwise regression analysis indicated that facial pigmentation was associated with carotid IMT via visceral fat area. CONCLUSION: Facial pigmentation may be a useful biomarker for carotid atherosclerosis in Japanese women.


Asunto(s)
Enfermedades de las Arterias Carótidas/diagnóstico , Enfermedades de las Arterias Carótidas/epidemiología , Cara/patología , Pigmentación de la Piel , Piel/patología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores , Colorimetría/métodos , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Japón/epidemiología , Persona de Mediana Edad , Fotograbar/métodos , Prevalencia , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
8.
Br J Dermatol ; 166(2): 322-30, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21936856

RESUMEN

BACKGROUND: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are characterized by keratinocyte apoptosis and necrosis, resulting in epidermal detachment. Although monocytes abundantly infiltrate the epidermis in SJS/TEN skin lesions, the properties and functions of these cells have not been fully examined. OBJECTIVES: To determine the properties of monocytes infiltrating into the epidermis in SJS/TEN. METHODS: Immunostaining of skin sections was performed to examine the membrane markers of monocytes infiltrating into skin lesions. RESULTS: Immunostaining of cryosections from 11 SJS/TEN skin lesions revealed numerous CD14+ monocytes located along the dermoepidermal junction and throughout the epidermis. The cells coexpressed CD16, CD11c and HLA-DR. CD14+ CD16+ cells were identified in very early lesions without epidermal damage, suggesting that their infiltration is a cause, rather than a result, of epidermal damage. Moreover, these cells expressed CD80, CD86 and CD137 ligand, indicative of their ability to facilitate the proliferation and cytotoxicity of CD8+ T cells. CD16+ cells infiltrating the epidermis and detected at the dermoepidermal junction were immunostained and counted in paraffin-embedded skin sections obtained from 47 patients with drug rash manifested as TEN, SJS, maculopapular-type rash or erythema multiform-type rash. The number of CD16+ monocytes infiltrating the epidermis increased significantly, depending on the grade of epidermal damage. CONCLUSIONS: These findings suggest that the appearance of CD14+ CD16+ cells of monocyte lineage plays an important role in the epidermal damage associated with SJS/TEN, most probably by enhancing the cytotoxicity of CD8+ T cells.


Asunto(s)
Receptores de Lipopolisacáridos/metabolismo , Monocitos/metabolismo , Receptores de IgG/metabolismo , Síndrome de Stevens-Johnson/patología , Ligando 4-1BB/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Apoptosis/fisiología , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Linaje de la Célula , Proliferación Celular , Epidermis/patología , Femenino , Humanos , Inmunohistoquímica , Queratinocitos/patología , Masculino , Persona de Mediana Edad , Síndrome de Stevens-Johnson/inmunología
10.
Diabetologia ; 50(9): 1900-1909, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17632702

RESUMEN

AIMS/HYPOTHESIS: We examined the effect of glucagon-like peptide-1 (GLP-1) on the development of diabetes and islet morphology in NOD mice by administering GLP-1 to prediabetic mice. METHODS: Eight-week-old female NOD mice were infused subcutaneously with human GLP-1 via a mini-osmotic pump for 4 or 8 weeks. In mice treated with GLP-1 for 4 weeks, blood glucose levels and body weight were measured. An intraperitoneal glucose tolerance test (IPGTT) and evaluation of insulitis score were also performed. Beta cell area, proliferation, apoptosis, neogenesis from ducts and subcellular localisation of forkhead box O1 (FOXO1) were examined by histomorphometrical, BrdU-labelling, TUNEL, insulin/cytokeratin and FOXO1/insulin double-immunostaining methods, respectively. RESULTS: Mice treated with human GLP-1 for 4 weeks had lower blood glucose levels until 2 weeks after completion of treatment, showing improved IPGTT data and insulitis score. This effect continued even after cessation of the treatment. In addition to the increase of beta cell neogenesis, BrdU labelling index was elevated (0.24 vs 0.13%, p < 0.001), while apoptosis was suppressed by 54.2% (p < 0.001) in beta cells. Beta cell area was increased in parallel with the translocation of FOXO1 from the nucleus to the cytoplasm. The onset of diabetes was delayed in mice treated with GLP-1 for 4 weeks, while mice treated with GLP-1 for 8 weeks did not develop diabetes by age 21 weeks compared with a 60% diabetes incidence in control mice at this age. CONCLUSIONS/INTERPRETATION: Continuous infusion of human GLP-1 to prediabetic NOD mice not only induces beta cell proliferation and neogenesis, but also suppresses beta cell apoptosis and delays the onset of type 1 diabetes.


Asunto(s)
Diabetes Mellitus Tipo 1/prevención & control , Péptido 1 Similar al Glucagón/fisiología , Fragmentos de Péptidos/fisiología , Animales , Glucemia/metabolismo , División Celular , Diabetes Mellitus Tipo 1/patología , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Inmunohistoquímica , Células Secretoras de Insulina/citología , Ratones , Ratones Endogámicos NOD , Páncreas/patología
11.
Diabetologia ; 50(3): 596-601, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17221211

RESUMEN

AIMS/HYPOTHESIS: Type 1A diabetes results from autoimmune destruction of pancreatic beta cells. We examined the involvement of TNF-alpha and IL-1beta, as well as of T cells, macrophages and dendritic cells, in the destruction of beta cells in patients with recent-onset type 1 diabetes. MATERIALS AND METHODS: We obtained pancreatic biopsy specimens from six patients with recent-onset type 1 diabetes and analysed these by immunohistochemistry. RESULTS: T cell infiltration was less common in islets without beta cells (12.5 [0-33.3]%) than in those with beta cells (46.0 [17.4-83.3]%), while macrophages and dendritic cells showed a similar extent of infiltration into islets both with or without beta cells. TNF-alpha was detected in 25.0 (4.3-46.9)% of macrophages and 11.8 (0-40.0)% of dendritic cells infiltrating the islets in samples from each patient, but not at all in T cells. IL-1beta was detected in 1.8 (0-11.3)% of T cells infiltrating the islets with beta cells, while it was found in 19.2 (0-35.3)% of macrophages or 10.7 (0-31.3)% of dendritic cells infiltrating the islets in samples from each patient (all values median [range]). CONCLUSIONS/INTERPRETATION: Macrophages and dendritic cells infiltrate the islets and produce inflammatory cytokines (TNF-alpha and IL-1beta) during the development of type 1A diabetes.


Asunto(s)
Células Dendríticas/patología , Diabetes Mellitus Tipo 1/genética , Islotes Pancreáticos/fisiopatología , Macrófagos/patología , Factor de Necrosis Tumoral alfa/biosíntesis , Adolescente , Adulto , Antígenos CD/análisis , Femenino , Humanos , Células Secretoras de Insulina/patología , Islotes Pancreáticos/patología , Masculino , Factor de Necrosis Tumoral alfa/sangre
12.
Diabetologia ; 48(8): 1560-4, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15991022

RESUMEN

AIMS/HYPOTHESIS: We have previously reported that fulminant type 1 diabetes is characterised by an absence of diabetes-related antibodies and a remarkably abrupt onset. However, little is known about the mechanism of beta cell destruction in this diabetes subtype, and to obtain insights into the aetiology of the disease, we investigated residual endocrine cells and the expression of Fas and Fas ligand in fulminant type 1 diabetes. METHODS: Residual beta and alpha cells were morphologically assessed in pancreatic tissue obtained by biopsy from five patients with recent-onset fulminant type 1 diabetes and five patients with recent-onset typical autoimmune type 1 diabetes. In addition, the expression of Fas and Fas ligand was evaluated by immunohistochemistry. RESULTS: In fulminant type 1 diabetes, beta and alpha cell areas were decreased significantly, compared with autoimmune type 1 diabetes and control subjects. In contrast, the alpha cell area was not decreased significantly in autoimmune type 1 diabetes, compared with that in control subjects. No Fas expression in islets and Fas ligand expression in CD3(+) cells in the exocrine pancreas were found in the fulminant type 1 diabetic patients who underwent this evaluation. CONCLUSIONS/INTERPRETATION: Our study showed that beta and alpha cells are damaged in fulminant type 1 diabetes. In addition to the lack of Fas and Fas ligand expression, the results suggest that the mechanism of beta cell destruction in fulminant type 1 diabetes is different from that in autoimmune type 1 diabetes.


Asunto(s)
Diabetes Mellitus Tipo 1/patología , Islotes Pancreáticos/patología , Acidosis/metabolismo , Adulto , Proteína Ligando Fas , Femenino , Humanos , Inmunohistoquímica , Islotes Pancreáticos/metabolismo , Cetoácidos/metabolismo , Cetosis/metabolismo , Masculino , Glicoproteínas de Membrana/biosíntesis , Páncreas Exocrino/metabolismo , Receptor fas/biosíntesis
14.
Cell Death Differ ; 12(1): 25-37, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15499374

RESUMEN

CD95 apoptosis resistance of tumor cells is often acquired through mutations in the death domain (DD) of one of the CD95 alleles. Furthermore, Type I cancer cells are resistant to induction of apoptosis by soluble CD95 ligand (CD95L), which does not induce efficient formation of the death-inducing signaling complex (DISC). Here, we report that tumor cells expressing a CD95 allele that lacks a functional DD, splenocytes from heterozygous lpr(cg) mice, which express one mutated CD95 allele, and Type I tumor cells stimulated with soluble CD95L can all die through CD95 when protein synthesis or nuclear factor kappa B is inhibited. This noncanonical form of CD95-mediated apoptosis is dependent on the enzymatic activity of procaspase-8 but does not involve fully processed active caspase-8 subunits. Our data suggest that it is possible to overcome the CD95 apoptosis resistance of many tumor cells that do not efficiently form a DISC through noncanonical activation of the caspase-8 proenzyme.


Asunto(s)
Apoptosis/fisiología , Caspasas/metabolismo , Receptor fas/fisiología , Alelos , Clorometilcetonas de Aminoácidos/farmacología , Animales , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Caspasa 8 , Inhibidores de Caspasas , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cicloheximida/farmacología , Inhibidores de Cisteína Proteinasa/farmacología , Dactinomicina/farmacología , Proteínas Adaptadoras de Señalización del Receptor del Dominio de Muerte , Resistencia a Antineoplásicos , Activación Enzimática , Proteína Ligando Fas , Humanos , Glicoproteínas de Membrana/farmacología , Ratones , Ratones Endogámicos C3H , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mutación , FN-kappa B/antagonistas & inhibidores , Oligopéptidos/farmacología , Receptores del Factor de Necrosis Tumoral/metabolismo , Receptor fas/genética
15.
Horm Metab Res ; 35(9): 537-40, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-14517770

RESUMEN

Adiponectin is a plasma protein exclusively secreted by adipose tissue, which plays a role in modulating lipid and glucose metabolism. The plasma adiponectin concentration shows an inverse correlation with the body mass index in normal and obese individuals, but it has not been investigated in subjects with an extremely low body weight and undernutrition such as anorexia nervosa patients. We investigated plasma adiponectin levels in 21 females with anorexia nervosa. Nineteen healthy females served as the lean control group. The subjects with anorexia nervosa had a significantly lower weight and showed a tendency towards higher adiponectin levels than the control group. No correlation between adiponectin and BMI was found in patients with anorexia nervosa, while a linear negative correlation was seen in lean controls. The patient who showed the lowest adiponectin level reached a life-threatening state and required intravenous feeding in hospital. In association with improved nutrition and weight gain, the adiponectin level increased gradually until the body mass index was about 16 and then decreased subsequently as would be expected in lean normal subjects. These observations suggest that adipose tissue secretes less adiponectin and the adiponectin levels do not show an inverse correlation simply with body mass index in some subjects with severe undernutrition.


Asunto(s)
Tejido Adiposo/metabolismo , Anorexia Nerviosa/sangre , Índice de Masa Corporal , Péptidos y Proteínas de Señalización Intercelular , Proteínas/metabolismo , Adiponectina , Adolescente , Adulto , Femenino , Humanos , Plasma/química , Proteínas/análisis , Valores de Referencia
16.
Br J Dermatol ; 147(2): 368-70, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12174115

RESUMEN

Exercise-induced anaphylaxis (EIA) is a form of physical urticaria that is induced by exercise. A 16-year-old Japanese boy had a 4-year history of recurrent wealing and dyspnoea after physical exercise such as jogging, playing handball or riding a bicycle in winter. The episodes were not associated with ingestion of foods including wheat or soya bean. A provocation test, with 15 min of exercise and 2 min of cold stimulation immediately before or immediately after the exercise, elicited a weal that was localized to the test area. A challenge test with ingestion of boiled soya beans and exercise did not elicit a weal. Therefore, in this case, cold exposure, but not food ingestion, was essential for inducing EIA. Cold-dependent EIA is different from cold urticaria, food-dependent EIA, cholinergic urticaria and cold-induced cholinergic urticaria, and may be a distinct entity.


Asunto(s)
Frío/efectos adversos , Ejercicio Físico , Hipersensibilidad/etiología , Adolescente , Diagnóstico Diferencial , Prueba de Esfuerzo/efectos adversos , Humanos , Hipersensibilidad/diagnóstico , Masculino , Anafilaxis Cutánea Pasiva , Pruebas Cutáneas
17.
Nature ; 414(6864): 625-7, 2001 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-11740556

RESUMEN

The photocatalytic splitting of water into hydrogen and oxygen using solar energy is a potentially clean and renewable source for hydrogen fuel. The first photocatalysts suitable for water splitting, or for activating hydrogen production from carbohydrate compounds made by plants from water and carbon dioxide, were developed several decades ago. But these catalysts operate with ultraviolet light, which accounts for only 4% of the incoming solar energy and thus renders the overall process impractical. For this reason, considerable efforts have been invested in developing photocatalysts capable of using the less energetic but more abundant visible light, which accounts for about 43% of the incoming solar energy. However, systems that are sufficiently stable and efficient for practical use have not yet been realized. Here we show that doping of indium-tantalum-oxide with nickel yields a series of photocatalysts, In(1-x)Ni(x)TaO(4) (x = 0-0.2), which induces direct splitting of water into stoichiometric amounts of oxygen and hydrogen under visible light irradiation with a quantum yield of about 0.66%. Our findings suggest that the use of solar energy for photocatalytic water splitting might provide a viable source for 'clean' hydrogen fuel, once the catalytic efficiency of the semiconductor system has been improved by increasing its surface area and suitable modifications of the surface sites.

18.
Biosci Biotechnol Biochem ; 65(9): 2098-101, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11676029

RESUMEN

Porcine mammary epithelial cells were isolated to culture on collagen gel followed by gel floating treatment to evaluate differentiation under the culture conditions of serum-free medium, supplemented with combinations of insulin, hydrocortisone, and prolactin. After the culture period, the mammary cells attached to the collagen gels were recovered to observe expression of beta-casein, beta-lactoglobulin, and lactoferrin by reverse transcriptase polymeric chain reaction method. Expression of beta-casein was observed in the presence of insulin, hydrocortisone, and prolactin whereas transcription of beta-lactoglobulin and lactoferrin occured irrespective of hydrocortisone and prolactin. Immunoblot analysis demonstrated synthesis and secretion of lactoferrin in the fraction of recovered cells and the culture medium.


Asunto(s)
Glándulas Mamarias Animales/citología , Glándulas Mamarias Animales/fisiología , Proteínas de la Leche/metabolismo , Animales , Técnicas de Cultivo de Célula/métodos , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Medio de Cultivo Libre de Suero/farmacología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/fisiología , Femenino , Hidrocortisona/farmacología , Insulina/farmacología , Glándulas Mamarias Animales/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Proteínas de la Leche/efectos de los fármacos , Proteínas de la Leche/genética , Prolactina/farmacología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Porcinos
19.
J Dermatol Sci ; 27(2): 130-9, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11532377

RESUMEN

The recruitment of immature dendritic cells into the epidermis is a key step in the development of cutaneous immunity, although the mechanism remains to be clarified. Recently, it was reported that both macrophage inflammatory protein 3alpha (MIP-3alpha)/CCL20 produced by keratinocytes and TNF-alpha are important in recruiting Langerhans cells (LC) to the epidermis. In this study, we examined the production of MIP-3alpha by human keratinocytes stimulated with TNF-alpha. Cultured keratinocytes showed enhanced expression of MIP-3alpha mRNA and protein when stimulated with TNF-alpha. In addition, conditioned medium from TNF-alpha-stimulated keratinocyte cultures induced the migration of L1.2 cells expressing CCR6. We next examined the production of MIP-3alpha in stratified keratinocytes and found that, in contrast to non-stratified keratinocytes, stimulation with TNF-alpha increased the expression of MIP-3alpha mRNA and protein. Moreover, skin samples grown in organ culture and treated with TNF-alpha showed MIP-3alpha in the keratinocytes of the spinous layer, but not in the basal layer, by immunofluorescence staining. Based on these results, we postulate that MIP-3alpha produced by keratinocytes in the spinous layer in response to TNF-alpha stimulation is a key chemokine responsible for the epidermal recruitment of Langerhans cells.


Asunto(s)
Quimiocinas CC/genética , Regulación de la Expresión Génica/efectos de los fármacos , Queratinocitos/fisiología , Proteínas Inflamatorias de Macrófagos/genética , Receptores de Quimiocina , Fenómenos Fisiológicos de la Piel , Piel/citología , Transcripción Genética/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología , Diferenciación Celular , Células Cultivadas , Quimiocina CCL20 , Quimiotaxis/efectos de los fármacos , Quimiotaxis/fisiología , Humanos , Queratinocitos/citología , Queratinocitos/efectos de los fármacos , Técnicas de Cultivo de Órganos , ARN Mensajero/genética , Receptores CCR6 , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Piel/efectos de los fármacos
20.
J Biol Chem ; 276(2): 999-1004, 2001 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-11029458

RESUMEN

Cells differentiate in response to various extracellular stimuli. This cellular response requires intracellular signaling pathways. The mitogen-activated protein (MAP) kinase cascade is a core signal transduction pathway that determines the fate of many kinds of cell. MAP kinase kinase kinase activates MAP kinase kinase, which in turn activates MAP kinase. Apoptosis signal-regulating kinase (ASK1) was identified as a MAP kinase kinase kinase involved in the stress-induced apoptosis-signaling cascade that activates the SEK1-JNK and MKK3/MKK6-p38 MAP kinase cascades. Expression of the constitutively active form of ASK1 (ASK1-DeltaN) in keratinocytes induced significant morphological changes and differentiation markers, transglutaminase-1, loricrin, and involucrin. A transient increase in p21(Cip1/WAF1) reduced DNA synthesis, and cell cycle analysis verified the differentiation. p38 MAP kinase inhibitors, SB202190 and SB203580, abolished the induction of differentiation markers, transglutaminase-1, loricrin, and involucrin. In turn, the induction of differentiation with ceramide in keratinocytes caused an increase in ASK1 expression and activity. Furthermore, normal human skin expresses ASK1 protein in the upper epidermis, implicating ASK1 in in vivo keratinocyte differentiation. We propose that the ASK1-p38 MAP kinase cascade is a new intracellular regulator of keratinocyte differentiation.


Asunto(s)
Diferenciación Celular/fisiología , Queratinocitos/citología , Queratinocitos/enzimología , MAP Quinasa Quinasa 4 , Quinasas Quinasa Quinasa PAM/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Inhibidores Enzimáticos/farmacología , Genes Reporteros , Humanos , Imidazoles/farmacología , Proteínas Quinasas JNK Activadas por Mitógenos , Queratinocitos/efectos de los fármacos , Cinética , MAP Quinasa Quinasa Quinasa 5 , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Piridinas/farmacología , Transfección , Proteínas Quinasas p38 Activadas por Mitógenos
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