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1.
Geophys Res Lett ; 49(15): e2022GL099655, 2022 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-36247517

RESUMEN

Microbursts are impulsive (<1 s) injections of electrons into the atmosphere, thought to be caused by nonlinear scattering by chorus waves. Although attempts have been made to quantify their contribution to outer belt electron loss, the uncertainty in the overall size and duration of the microburst region is typically large, so that their contribution to outer belt loss is uncertain. We combine datasets that measure chorus waves (Van Allen Probes [RBSP], Arase, ground-based VLF stations) and microburst (>30 keV) precipitation (FIREBIRD II and AC6 CubeSats, POES) to determine the size of the microburst-producing chorus source region beginning on 5 December 2017. We estimate that the long-lasting (∼30 hr) microburst-producing chorus region extends from 4 to 8 Δ MLT and 2-5 Δ L. We conclude that microbursts likely represent a major loss source of outer radiation belt electrons for this event.

2.
J Food Sci Technol ; 57(3): 1003-1012, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32123421

RESUMEN

To meet the needs of new consumers, meat researchers need to develop healthier products. Dietary fibers can be added for structural purposes, to present functional characteristics or to change the composition of the final product. In this study, mixture design was used to investigate the effects of partial substitution of pork fat by inulin, fructooligosaccharides and α-cyclodextrin on the technological and sensory quality characteristics of low-fat Italian type salami. The partial substitution of fat using dietary fibers shows no effect on weight loss, Aw and pH during ripening time. However, the addition of up to 2% α-cyclodextrin increased lightness and reduced redness and yellowness. Up to 2% of inulin or fructooligosaccharides added improved the sensory acceptance, texture parameters and redness. Healthier low-fat Italian type salami can be produced using inulin or fructooligosaccharides as fat substitute for pork fat and still obtain good technological and sensorial results.

3.
Clin Genet ; 88(2): 155-60, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25046119

RESUMEN

In current practice of clinical genetics, molecular diagnosis has become more widely used than ever before. DNA diagnosis is important for appropriate medical care of the patient, and proper genetic counseling to the family. However, genetic testing of orphan disease cannot always be performed easily. In multiple congenital anomalies (MCA) syndromes by monogenic cause, the broad mutational spectrum and large size of responsible genes often make molecular diagnosis expensive and cumbersome. We solve this problem with on-demand genetic testing by CHIPS (CEL nuclease mediated heteroduplex incision with polyacrylamide gel electrophoresis and silver staining) technology, which is the ultimately conventional and economical mutation screening system. In this article, we show eight patients with MCA syndromes who were recently treated at our hospital, and demonstrate that CHIPS successfully offers efficient and inexpensive genetic testing and facilitates clinical genetic service in our local region.


Asunto(s)
Anomalías Múltiples/diagnóstico , Pruebas Genéticas/métodos , Técnicas de Diagnóstico Molecular/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Anomalías Múltiples/genética , Adulto , Niño , Femenino , Asesoramiento Genético , Humanos , Lactante , Recién Nacido , Masculino , Mutación/genética
4.
J Periodontal Res ; 50(6): 714-20, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25524144

RESUMEN

BACKGROUND AND OBJECTIVE: Oxytalan fibers are categorized as a microfibril assembly without elastin deposition, and are unique components in the periodontal ligament (PDL). However, little is known about their formation during PDL development. To clarify the mechanisms of oxytalan fiber formation in developing PDL, we performed immunohistochemical analysis to detect the direct expression of fibrillin-1 and fibrillin-2, which are major components of microfibrils. MATERIAL AND METHODS: Frozen sections of lower molars from mice at several stages of growth were prepared without chemical fixation and decalcification using the film transfer method. Immunostaining was performed with anti-fibrillin-1 and -2, and anticytokeratin antibodies. RESULTS: Fibrillin-1 was not expressed in the dental follicle during the crown forming stage. At postneonatal day 9, fibrillin-1 expression started with meshwork appearance between the epithelial cells from Hertwig's epithelial root sheath at the root dentin surface. Fibirillin-2 was detected much earlier than fibrillin-1 expression. Fibrillin-2 was expressed with a liner appearance, running parallel to the root axis in PDL, and was partially co-expressed with cytokeratin 14 expression in Hertwig's epithelial root sheath. Furthermore, we detected both fibrillin-1 and fibrillin-2 expression in human PDL. Fibrillin-1 was detected in fibers with a vertically oriented root axis in PDL. Fibrillin-2 was widely expressed in PDL, including around the epithelial cell rests of Malassez. Fibrillin-1 and fibrillin-2 were clearly co-expressed in thick fiber structures in human PDL. CONCLUSION: Our results suggest that both fibrillin-1 and fibrillin-2 expression is required to form thick oxytalan fibers in PDL. Based on the expression patterns for fibrillin-1 and fibrillin-2, they have different functions during tooth root and PDL development. Early expression of fibrillin-2 may regulate dental epithelial cell behavior during root and PDL development.


Asunto(s)
Fibrilina-1/análisis , Fibrilina-2/análisis , Diente/crecimiento & desarrollo , Animales , Inmunohistoquímica , Ratones , Ligamento Periodontal/crecimiento & desarrollo
5.
J Clin Pharm Ther ; 38(1): 12-5, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22882748

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: It has been reported that ibuprofen interferes with the antiplatelet effect of low-dose aspirin. This interaction is ascribed to steric hindrance at the active site of cyclooxygenase-1 by ibuprofen, when aspirin is administered after ibuprofen. However, whether other non-steroidal anti-inflammatory drugs (NSAIDs) interact with aspirin similarly is not well defined. The aim of this study was to assess the influence of nine NSAIDs on the antiplatelet effect of aspirin. METHODS: We investigated the antiplatelet effect of NSAIDs using steady-state plasma concentration reported after usual doses. We studied the in vitro antiplatelet effect of NSAID alone, aspirin alone, aspirin before NSAID addition and aspirin after NSAID addition to platelet-rich plasma. The rates of platelet aggregation induced by collagen were determined. The final concentration of aspirin used was the 50% effective concentration (EC(50)) previously estimated in vitro. RESULTS AND DISCUSSION: Ibuprofen and mefenamic acid interfere with the antiplatelet effect of aspirin when added before the latter. The rate of platelet aggregation was reduced by 48·1% and 22·7%, respectively. The other NSAIDs tested did not significantly affect the aspirin antiplatelet effect when exposure was prior to aspirin. None of the nine NSAIDs altered the aspirin effect if administration followed that of aspirin. WHAT IS NEW AND CONCLUSION: Naproxen and flurbiprofen have significant antiplatelet effects at plasma concentrations seen with usual doses. Our in vitro model suggests that the antiplatelet effect of aspirin is significantly diminished when taken after, but not before, ibuprofen or mefenamic acid. None of the other NSAIDs tested had any effect irrespective of the timing of dosing.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Aspirina/farmacología , Inhibidores de Agregación Plaquetaria/farmacología , Agregación Plaquetaria/efectos de los fármacos , Antiinflamatorios no Esteroideos/administración & dosificación , Aspirina/administración & dosificación , Colágeno/administración & dosificación , Interacciones Farmacológicas , Femenino , Humanos , Técnicas In Vitro , Masculino , Factores de Tiempo
6.
Clin Exp Allergy ; 42(8): 1273-81, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22805475

RESUMEN

BACKGROUND: Dehydroxymethylepoxyquinomicin (DHMEQ) is a newly developed compound that inhibits nuclear factor κB activation and is reported to ameliorate animal models of various inflammatory diseases without significant adverse effects. Because nuclear factor κB is a transcription factor that plays a critical role in the pathophysiology of asthma, DHMEQ may be of therapeutic benefit in asthma. OBJECTIVE: The purpose of this study was to evaluate the effects of DHMEQ on airway inflammation and remodelling in murine models of asthma. METHODS: The BALB/c mice were sensitized and then challenged acutely or chronically with ovalbumin and administered DHMEQ intraperitoneally before each challenge. Inflammation of airways, lung histopathology and airway hyper responsiveness to methacholine challenge were evaluated. In addition, the effect of DHMEQ on production of cytokines and eotaxin-1 by murine splenocytes, human peripheral blood mononuclear cells and bronchial epithelial cells was investigated. RESULTS: Airway hyper responsiveness was ameliorated in both acutely and chronically challenged models by treatment with DHMEQ. DHMEQ significantly reduced eosinophilic airway inflammation and levels of Th2 cytokines in bronchoalveolar lavage fluid in the acute model. It also inhibited parameters of airway remodelling including mucus production, peribronchial fibrosis and the expression of α-smooth muscle actin. Moreover, the production of Th2 cytokines from murine splenocytes and human peripheral blood mononuclear cells and the production of eotaxin-1 by bronchial epithelial cells were inhibited by DHMEQ. CONCLUSIONS AND CLINICAL RELEVANCE: These results indicate that DHMEQ inhibits allergic airway inflammation and airway remodelling in murine models of asthma. DHMEQ may have therapeutic potential in the treatment of asthma.


Asunto(s)
Remodelación de las Vías Aéreas (Respiratorias)/efectos de los fármacos , Asma/tratamiento farmacológico , Benzamidas/farmacología , Ciclohexanonas/farmacología , Inflamación/tratamiento farmacológico , FN-kappa B/antagonistas & inhibidores , Animales , Asma/metabolismo , Asma/patología , Benzamidas/administración & dosificación , Líquido del Lavado Bronquioalveolar/inmunología , Células Cultivadas , Ciclohexanonas/administración & dosificación , Citocinas/inmunología , Citocinas/metabolismo , Modelos Animales de Enfermedad , Eosinófilos/inmunología , Eosinófilos/patología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Femenino , Humanos , Inflamación/metabolismo , Inflamación/patología , Mediadores de Inflamación/metabolismo , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Ratones , Ratones Endogámicos BALB C , FN-kappa B/metabolismo , Hipersensibilidad Respiratoria/tratamiento farmacológico , Hipersensibilidad Respiratoria/metabolismo
7.
Mol Psychiatry ; 16(3): 307-20, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20142818

RESUMEN

Neuregulin-1 (NRG1) is implicated in the etiology or pathology of schizophrenia, although its biological roles in this illness are not fully understood. Human midbrain dopaminergic neurons highly express NRG1 receptors (ErbB4). To test its neuropathological role in the neurodevelopmental hypothesis of schizophrenia, we administered type-1 NRG1 protein to neonatal mice and evaluated the immediate and subsequent effects on dopaminergic neurons and their associated behaviors. Peripheral NRG1 administration activated midbrain ErbB4 and elevated the expression, phosphorylation and enzyme activity of tyrosine hydroxylase (TH), which ultimately increased dopamine levels. The hyperdopaminergic state was sustained in the medial prefrontal cortex after puberty. There were marked increases in dopaminergic terminals and TH levels. In agreement, higher amounts of dopamine were released from this brain region of NRG1-treated mice following high potassium stimulation. Furthermore, NRG1-treated mice exhibited behavioral impairments in prepulse inhibition, latent inhibition, social behaviors and hypersensitivity to methamphetamine. However, there were no gross abnormalities in brain structures or other phenotypic features of neurons and glial cells. Collectively, our findings provide novel insights into neurotrophic contribution of NRG1 to dopaminergic maldevelopment and schizophrenia pathogenesis.


Asunto(s)
Encéfalo , Dopamina/metabolismo , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Neurregulina-1/farmacología , Estimulación Acústica , Animales , Animales Recién Nacidos , Conducta Animal/efectos de los fármacos , Biotinilación , Encéfalo/efectos de los fármacos , Encéfalo/crecimiento & desarrollo , Encéfalo/metabolismo , Antagonistas de Dopamina/farmacología , Relación Dosis-Respuesta a Droga , Audición/efectos de los fármacos , Inmunoprecipitación , Levodopa/metabolismo , Locomoción/efectos de los fármacos , Metanfetamina/farmacología , Ratones , Microdiálisis/métodos , Fosforilación/efectos de los fármacos , Potasio/farmacología , Proteínas Proto-Oncogénicas c-fos/metabolismo , Reflejo de Sobresalto/efectos de los fármacos , Risperidona/farmacología , Conducta Social , Estadísticas no Paramétricas , Tirosina 3-Monooxigenasa/metabolismo
8.
Eur J Vasc Endovasc Surg ; 44(1): 73-6, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22546640

RESUMEN

OBJECTIVES: Sclerotherapy is useful for the treatment of arteriovenous vascular malformations. However, intravascular administration of sclerotic agents into small arteriovenous niduses is often difficult. Extravascular administration of sclerotic agents causes reduction of vascular flow on Doppler echo during clinical sclerotherapy. Therefore, we aimed to investigate whether the extravascular injection of sclerotic agents affects tiny vessels. DESIGN: Animal study. MATERIALS: The effect of extravascular injection of sclerotic agents on vessels was investigated using rat femoral and superficial inferior epigastric vessels. METHODS: After surgical exposure of vessels, absolute ethanol, 5% ethanolamine oleate and 3% polidocanol were injected into perivascular surrounding tissues, and their effect on vessels was evaluated after 14 days using histology and coloured silicone rubber injection. RESULTS: The integrity of the vascular lumen, endothelial cells and vascular patency were not affected by injection of sclerotic agents. CONCLUSIONS: Attenuation of vascular flow of an arteriovenous shunt after extravascular injection of sclerotic agents is transient and/or trivial and does not cause disruption of vessels. Therefore, sclerotic agents should be delivered to obtain sufficient destruction of arteriovenous malformation lesions and blood flow.


Asunto(s)
Malformaciones Arteriovenosas/terapia , Arterias Epigástricas/efectos de los fármacos , Arteria Femoral/efectos de los fármacos , Vena Femoral/efectos de los fármacos , Soluciones Esclerosantes/administración & dosificación , Escleroterapia/métodos , Animales , Modelos Animales de Enfermedad , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/patología , Arterias Epigástricas/anomalías , Etanol/administración & dosificación , Arteria Femoral/anomalías , Vena Femoral/anomalías , Estudios de Seguimiento , Inyecciones , Ácidos Oléicos/administración & dosificación , Polidocanol , Polietilenglicoles/administración & dosificación , Ratas , Ratas Wistar , Solventes/administración & dosificación , Adhesivos Tisulares , Resultado del Tratamiento
9.
Eur Rev Med Pharmacol Sci ; 26(21): 8039-8056, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36394755

RESUMEN

OBJECTIVE: Metformin, a medicine used for the treatment of type 2 diabetes, was previously reported to suppress age-dependent hyperproliferation of intestinal stem cells in Drosophila. Here, we aimed to investigate its anti-aging effects on other tissues, such as adult muscle and elucidate the mechanisms underlying the anti-ageing effect. MATERIALS AND METHODS: To evaluate the anti-muscle ageing effect of Metformin, we visualized ubiquitinated protein aggregates accumulated in adult muscle as the flies age by immunostaining and measured the total pixel size of the aggregates. We altered gene expression in the muscle by induction of dsRNA against the relevant mRNAs or mRNAs encoding the constitutively active mutant proteins using the Gal4/UAS system. We determined the mRNA levels by quantitative Real Time-Polymerase Chain Reaction (QRT-PCR). RESULTS: Continuous metformin feeding significantly extended the lifespan of Drosophila adults. Furthermore, the feeding suppressed the aging-dependent accumulation of ubiquitinated aggregates in adult muscle. To delineate the mechanism through which metformin influences the muscle aging phenotype, we induced the constitutively active AMPK specifically in the muscles and found that the activation of the AMPK-mediated pathway was sufficient for the anti-aging effect of Metformin. Furthermore, the AMPK-mediated downregulation of Tor-mediated pathways, subsequent induction of an eIF-4E inhibitor were involved in the effect. These genetic data suggested that the metformin effect is related to the partial suppression of protein synthesis in ribosomes. Furthermore, metformin stimulated autophagy induction in adult muscles. CONCLUSIONS: Our results suggest that metformin can be regarded as an anti-aging compound in Drosophila muscle. The stimulation of autophagy was also involved in the anti-aging effect, which delayed the progression of muscle aging in Drosophila adults.


Asunto(s)
Diabetes Mellitus Tipo 2 , Metformina , Animales , Metformina/farmacología , Drosophila/metabolismo , Adenilato Quinasa , Proteínas Quinasas Activadas por AMP/metabolismo , Envejecimiento
10.
Kyobu Geka ; 64(7): 587-9, 2011 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-21766713

RESUMEN

We report a case of successful treatment of a ruptured distal aortic arch aneurysm with cardiac tamponade by using selective cerebral perfusion for protecting the brain. A 79-year-old man had sudden onset of severe chest and back pain. Chest computed tomography (CT) suggested an acute aortic dissection. He was immediately transferred to the emergency room of our hospital. Echocardiography performed on admission revealed intrapericardial fluid, and hemodynamic monitoring suggested cardiac tamponade. After pericardiocentesis and removal of 400 ml bloody fluid, his hemodynamic condition became stable. Enhanced chest CT showed ruptured distal aortic arch aneurysm with pericardial and pleural effusion. Emergency patch plasty of the aneurysm under extracorporeal circulation (ECC) was performed, assisted by selective cerebral perfusion and deep hypothermia. The patient's postoperative course was uneventful, except for minor transient respiratory troubles, and he was able return to his usual activity.


Asunto(s)
Aorta Torácica , Aneurisma de la Aorta Torácica/cirugía , Rotura de la Aorta/cirugía , Taponamiento Cardíaco/etiología , Anciano , Rotura de la Aorta/complicaciones , Humanos , Masculino
11.
J Neural Transm (Vienna) ; 117(7): 887-95, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20526724

RESUMEN

Neuregulin-1 (NRG1) gene is implicated in the etiology or neuropathology of schizophrenia, although its biological contribution to this illness is not fully understood. We have established an enzyme-linked immunosorbent assay (ELISA), which recognizes the NRG1beta1 immunoglobulin-like (Ig) domain, and measured soluble Ig-NRG1 immunoreactivity in the sera of chronic schizophrenia patients (n = 40) and healthy volunteers (n = 59). ELISA detected remarkably high concentrations of Ig-NRG1 immunoreactivity in human serum (mean 5.97 +/- 0.40 ng/mL, ~213 +/- 14 pM). Gender and diagnosis exhibited significant effects on serum Ig-NRG1 immunoreactivity. Mean Ig-NRG1 immunoreactivity in the schizophrenia group was 63.2% of that measured in the control group. Ig-NRG1 immunoreactivity in women was 147.1% of that seen in men. We also attempted to correlate six SNPs of NRG1 genome with serum Ig-NRG1 immunoreactivity. Analysis of covariance with compensation for gender identified a significant interaction between diagnosis and SNP8NRG243177 allele. The T allele of this SNP significantly contributed to the disease-associated decrease in Ig-NRG1 immunoreactivity. Although we hypothesized a chronic influence of antipsychotic medications, there was no significant effect of chronic haloperidol treatment on serum Ig-NRG1 immunoreactivity in monkeys. These findings suggest that serum NRG1 levels are decreased in patients with chronic schizophrenia and influenced by their SNP8NRG243177 alleles.


Asunto(s)
Neurregulina-1/sangre , Neurregulina-1/genética , Polimorfismo de Nucleótido Simple , Esquizofrenia/sangre , Esquizofrenia/genética , Adulto , Alelos , Análisis de Varianza , Animales , Antipsicóticos/administración & dosificación , Antipsicóticos/farmacología , Estudios de Casos y Controles , Enfermedad Crónica , Femenino , Haloperidol/administración & dosificación , Haloperidol/farmacología , Humanos , Macaca fascicularis , Masculino , Esquizofrenia/tratamiento farmacológico , Factores Sexuales
12.
Anaesthesia ; 65(6): 564-568, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20412151

RESUMEN

We compared the efficacy of the Airway Scope and McCoy laryngoscope as intubation tools with the neck stabilised by a rigid cervical collar. After induction of anaesthesia and neck stabilisation, 100 patients were randomly assigned to tracheal intubation with an Airway Scope or McCoy laryngoscope. Overall intubation success rate, time required for intubation, number of intubation attempts required for successful intubation, and airway complications related to intubation were recorded. Overall intubation success rates were 100% with both devices and a similar number of intubation attempts were required. However, the mean (SD) time required for successful intubation was shorter with the Airway Scope (30 (7) s) than with the McCoy laryngoscope (40 (14) s; p < 0.0001). The incidences of intubation complications were similar, but oesophageal intubation (in six cases) occurred only with McCoy laryngoscope.


Asunto(s)
Intubación Intratraqueal/instrumentación , Laringoscopios , Cuello , Restricción Física , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Aparatos Ortopédicos , Factores de Tiempo , Adulto Joven
13.
J Oral Rehabil ; 37(4): 235-41, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20074118

RESUMEN

The aim of this study was to determine anatomical locations of the hinge axis point, kinematic axis point and reference point for the palpated lateral condylar pole on lateral cephalograms. Subjects comprised 18 Japanese women selected according to following criteria: normal occlusion; and absence of signs and symptoms of stomatognathic function. Jaw movement and the condylar reference points noted earlier were recorded three-dimensionally with six degrees of freedom, and kinematic axis point and hinge axis point were determined using an optoelectronic jaw-tracking system. Lateral cephalograms were used to determine anatomical locations of the three points in the condyle. Mean location of hinge axis point was 12.9 mm anterior of the porion and 5.3 mm inferior to the Frankfort horizontal plane, the kinematic axis point was situated in 12.8 mm anterior and 0.1 mm inferior, and the reference point for the palpated lateral condylar pole was situated 10.7 mm anterior and 0.8 mm inferior, respectively. The kinematic axis point was located outside the condyle in the majority of subjects. The reference point for the palpated lateral pole offers a useful indicator in the analysis of condylar movements.


Asunto(s)
Cefalometría/normas , Maloclusión Clase I de Angle/etnología , Cóndilo Mandibular/anatomía & histología , Rango del Movimiento Articular , Articulación Temporomandibular/fisiología , Fenómenos Biomecánicos , Femenino , Humanos , Imagenología Tridimensional , Japón , Movimiento/fisiología , Valores de Referencia , Articulación Temporomandibular/anatomía & histología , Adulto Joven
14.
Anaesth Rep ; 8(2): 98-100, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33251512

RESUMEN

Priming doses of non-depolarising neuromuscular blocking drugs given before administration of anaesthetic agents have been used to hasten the onset of neuromuscular blockade. In the settings of coronavirus disease 2019 (COVID-19), this could be used to reduce the apnoeic, and potentially aerosol-generating, window. To our knowledge, we report the first cases of tracheal intubation with rocuronium for COVID-19 using the priming principle. Both patients needed their tracheas intubated for severe hypoxia using a rapid sequence induction technique with a priming dose of rocuronium. Despite adequate pre-oxygenation a sudden, unexpected fall in arterial oxygen saturations was observed in both patients after administration of a priming dose of 2 mg of rocuronium. Clinicians should consider this possible risk associated with priming doses of neuromuscular blocking drugs in the management of patients with respiratory failure due to COVID-19.

15.
Sci Rep ; 10(1): 3380, 2020 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-32098993

RESUMEN

The brightness of aurorae in Earth's polar region often beats with periods ranging from sub-second to a few tens of a second. Past observations showed that the beat of the aurora is composed of a superposition of two independent periodicities that co-exist hierarchically. However, the origin of such multiple time-scale beats in aurora remains poorly understood due to a lack of measurements with sufficiently high temporal resolution. By coordinating experiments using ultrafast auroral imagers deployed in the Arctic with the newly-launched magnetospheric satellite Arase, we succeeded in identifying an excellent agreement between the beats in aurorae and intensity modulations of natural electromagnetic waves in space called "chorus". In particular, sub-second scintillations of aurorae are precisely controlled by fine-scale chirping rhythms in chorus. The observation of this striking correlation demonstrates that resonant interaction between energetic electrons and chorus waves in magnetospheres orchestrates the complex behavior of aurora on Earth and other magnetized planets.

16.
Science ; 165(3888): 85-6, 1969 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-17840698

RESUMEN

Reconstitution of 30S ribosomal particles from 16S ribosomal RNA and total proteins, or from core proteins and split proteins obtained from the ribosomes of strains of Escherichia coli sensitive to and resistant to spectinomycin, shows that the split protein fraction determines the response of polypeptide synthesis in virto to spectinomycin. Reconstitution of active particles in the presence of isolated split proteins allowed the identification of the single split protein responsible for spectinomycin sensitivity.

17.
Hepatogastroenterology ; 56(93): 971-7, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19760923

RESUMEN

BACKGROUND/AIMS: Liver regeneration after surgical resection is important. The present study was designed to understand the effect of background liver damage on the rate of liver tissue regeneration after hepatectomy and the mechanism of any defective regeneration. METHODOLOGY: The subjects were 40 patients who underwent liver resection. They comprised 22 patients with chronic viral hepatitis-hepatocellular carcinoma (liver damage group) and 18 patients with hepatic metastases from colorectal cancer (normal liver group). Liver regeneration was evaluated by histopathological and immunohistochemical examination of the surgically resected tissue and by CT-scanning of the regenerated liver mass. The resected liver specimens were stained for c-met, gp-130 and nuclear factor-kappaB (NF-kappaB) proteins. RESULTS: Liver regeneration was significantly less in the liver-damage group than in the normal-liver group. Histopathological examination showed marked inflammatory cell infiltration in the liver-damage group. Expression of c-met, but not gp-130, was significantly higher on parenchymal cells of the liver-damage group than the normal-liver group. NF-kappaB expression in parenchymal liver cells was significantly higher than in non-parenchymal cells of the normal-liver group. In the liver-damage group, liver regeneration correlated negatively with the staining intensity of NF-kappaB protein in non-parenchymal cells. These findings suggest that non-parenchymal cells are constitutively activated in the damaged liver, probably explaining the refractoriness of hepatocytes to cytokine-induced proliferation after hepatectomy, in spite of increased receptor (c-met) expression. CONCLUSIONS: The refractory response of injured hepatocytes to cytokines may explain the impaired postoperative liver regeneration in patients with damaged liver.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/cirugía , Hepatectomía/métodos , Hepatitis Viral Humana/cirugía , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/cirugía , Regeneración Hepática/efectos de los fármacos , Carcinoma Hepatocelular/secundario , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Neoplasias Colorrectales/patología , Femenino , Humanos , Modelos Lineales , Neoplasias Hepáticas/secundario , Masculino , Persona de Mediana Edad , FN-kappa B/metabolismo , Proteína Oncogénica v-akt/metabolismo , Proteínas Proto-Oncogénicas c-met/metabolismo , Estadísticas no Paramétricas , Tomografía Computarizada por Rayos X
18.
PLoS One ; 14(12): e0220483, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31881024

RESUMEN

E. coli associated Hemolytic Uremic Syndrome (epidemic hemolytic uremic syndrome, eHUS) caused by Shiga toxin-producing bacteria is characterized by thrombocytopenia, microangiopathic hemolytic anemia, and acute kidney injury that cause acute renal failure in up to 65% of affected patients. We hypothesized that the mannose-binding lectin (MBL) pathway of complement activation plays an important role in human eHUS, as we previously demonstrated that injection of Shiga Toxin-2 (Stx-2) led to fibrin deposition in mouse glomeruli that was blocked by co-injection of the anti-MBL-2 antibody 3F8. However, the markers of platelet thrombosis in affected mouse glomeruli were not delineated. To investigate the effect of 3F8 on markers of platelet thrombosis, we used kidney sections from our mouse model (MBL-2+/+ Mbl-A/C-/-; MBL2 KI mouse). Mice in the control group received PBS, while mice in a second group received Stx-2, and those in a third group received 3F8 and Stx-2. Using double immunofluorescence (IF) followed by digital image analysis, kidney sections were stained for fibrin(ogen) and CD41 (marker for platelets), von-Willebrand factor (marker for endothelial cells and platelets), and podocin (marker for podocytes). Electron microscopy (EM) was performed on ultrathin sections from mice and human with HUS. Injection of Stx-2 resulted in an increase of both fibrin and platelets in glomeruli, while administration of 3F8 with Stx-2 reduced both platelet and fibrin to control levels. EM studies confirmed that CD41-positive objects observed by IF were platelets. The increases in platelet number and fibrin levels by injection of Stx-2 are consistent with the generation of platelet-fibrin thrombi that were prevented by 3F8.


Asunto(s)
Síndrome Hemolítico-Urémico/metabolismo , Lectina de Unión a Manosa/metabolismo , Trombosis/metabolismo , Lesión Renal Aguda/metabolismo , Animales , Plaquetas/metabolismo , Modelos Animales de Enfermedad , Células Endoteliales/metabolismo , Escherichia coli/metabolismo , Escherichia coli/patogenicidad , Infecciones por Escherichia coli/microbiología , Síndrome Hemolítico-Urémico/microbiología , Humanos , Riñón/metabolismo , Glomérulos Renales/metabolismo , Lectina de Unión a Manosa/inmunología , Ratones , Ratones Noqueados , Ratones Transgénicos , Toxina Shiga/metabolismo , Toxina Shiga II/metabolismo , Tromboembolia/metabolismo
19.
Neuron ; 10(6): 1113-9, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8318232

RESUMEN

Opsin expression is extremely suppressed by carotenoid deprivation in Drosophila. Carotenoid replacement in deprived flies promotes the recovery of visual pigment with an increase in opsin, as well as the chromophore 11-cis-3-hydroxyretinal. Here, we show that opsin mRNA and opsin peptide in an intermediate step of posttranslational processing were present in carotenoid-deprived flies. By supplementing chromophore to photoreceptor cells, intermediate opsin was made mature. During this process, opsin peptide underwent multiple modifications involving glycosylation. Based on these results, we present a novel mechanism of protein regulatory expression; that is, chromophore posttranslationally controls the expression of apoprotein by promoting its maturation.


Asunto(s)
Drosophila melanogaster/fisiología , Retinaldehído/análogos & derivados , Rodopsina/biosíntesis , Opsinas de Bastones/biosíntesis , Animales , Expresión Génica , Glicosilación , Immunoblotting , Células Fotorreceptoras/fisiología , Procesamiento Proteico-Postraduccional , ARN Mensajero/metabolismo , Retinaldehído/aislamiento & purificación , Retinaldehído/metabolismo , Rodopsina/aislamiento & purificación , Opsinas de Bastones/aislamiento & purificación , Transcripción Genética
20.
Diabetologia ; 51(12): 2299-302, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18850084

RESUMEN

AIMS/HYPOTHESIS: We analysed the association between humoral autoreactivity to zinc transporter-8 (ZnT8) and the SLC30A8 rs13266634 polymorphism (Arg325Trp), which is located at the most distal loop in the ZnT8 protein. METHODS: Autoantibodies to ZnT8 were determined by RIA in 270 patients with type 1 diabetes using ZnT8 carboxy-terminal constructs (amino acids 268-369) carrying 325Trp(CW) and 325Arg(CR) and a hybrid construct (CW-CR). Forty-four ZnT8 autoantibody-positive sera with genomic DNA were used to examine the association between reactivity to ZnT8 constructs and the rs13266634 genotype. RESULTS: Seventy-five patients reacted to the CW-CR hybrid construct, whereas 37 and 36 patients reacted to the CW and CR constructs, respectively. All sera positive for either CW or CR autoantibodies were positive for CW-CR autoantibodies. Among 19 patients with a 325Arg(CC) genotype, 5% had CW-specific autoantibodies, 42% had CR-specific autoantibodies and 32% had dual reactivity. Conversely, 73% of 15 patients with the 325Trp(TT) genotype had CW-specific autoantibodies, no patients had CR-specific autoantibodies and 13% had dual reactivity. Nine of the ten patients (90%) with the CT genotype reacted with either CR or CW constructs. The titre of CR autoantibodies in patients carrying the C allele was significantly higher than that in TT homozygotes (p < 0.0001). In contrast, the titre of CW autoantibodies in patients carrying a T allele was significantly higher than that in CC homozygotes (p < 0.005). No evidence of an association between rs13266634 and type 1 diabetes was observed. CONCLUSIONS/INTERPRETATION: These results indicate that variant residue at amino acid 325 is a key determinant of humoral autoreactivity to ZnT8 and that the SLC30A8 genotype is an important determinant of autoantibody specificity.


Asunto(s)
Especificidad de Anticuerpos/inmunología , Pueblo Asiatico/genética , Autoanticuerpos/inmunología , Proteínas de Transporte de Catión/genética , Proteínas de Transporte de Catión/inmunología , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/inmunología , Adolescente , Adulto , Anciano , Arginina/genética , Arginina/metabolismo , Proteínas de Transporte de Catión/metabolismo , Niño , Preescolar , Diabetes Mellitus Tipo 1/epidemiología , Diabetes Mellitus Tipo 1/metabolismo , Femenino , Humanos , Lactante , Recién Nacido , Japón/epidemiología , Masculino , Persona de Mediana Edad , Mutación/genética , Transportador 8 de Zinc
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