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1.
Sci Rep ; 9(1): 9862, 2019 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-31285481

RESUMEN

An estuary is a dynamic environment where marine and fluvial processes meet to form complex and transient morphology. The estuary morphology is largely determined by net sediment transport by two-way tidal flows, but the hydrodynamics also depends on the morphology of the tidal channels. The estuary inherently accommodates cyclic processes that are internally generated through hydro-morphodynamic interactions. In addition, the estuary evolves in response to changes in external forces by natural and anthropogenic factors. Morphological changes under the different controls often hinder the comprehension of the evolutionary processes of estuaries. Here we explored morphological changes in the Sittang River estuary, Myanmar, which has great morphological dynamism from extreme tidal energy and large sediment inputs, through field surveys and satellite imagery analysis. We identify an autocyclic process in a sedimentary system driving large-scale channel migration in decadal to multidecadal cycles. We show that drastic changes of the estuary morphology occasionally occur with rapid bank erosion through modulation of the cyclic channel migration under conflicting tidal and fluvial forces. This extreme case with minimal human intervention highlights channel migration as a key process in morphological evolution of tide-dominated estuaries undergoing active infilling.

2.
Sci Rep ; 8(1): 16185, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30385850

RESUMEN

Long-term daylight deprivation such as during the Antarctic winter has been shown to lead to delayed sleep timing and sleep fragmentation. We aimed at testing whether retinal sensitivity, sleep and circadian rest-activity will change during long-term daylight deprivation on two Antarctic bases (Concordia and Halley VI) in a total of 25 healthy crew members (mean age: 34 ± 11y; 7f). The pupil responses to different light stimuli were used to assess retinal sensitivity changes. Rest-activity cycles were continuously monitored by activity watches. Overall, our data showed increased pupil responses under scotopic (mainly rod-dependent), photopic (mainly L-/M-cone dependent) as well as bright-blue light (mainly melanopsin-dependent) conditions during the time without direct sunlight. Circadian rhythm analysis revealed a significant decay of intra-daily stability, indicating more fragmented rest-activity rhythms during the dark period. Sleep and wake times (as assessed from rest-activity recordings) were significantly delayed after the first month without sunlight (p < 0.05). Our results suggest that during long-term daylight deprivation, retinal sensitivity to blue light increases, whereas circadian rhythm stability decreases and sleep-wake timing is delayed.


Asunto(s)
Ritmo Circadiano/fisiología , Retina/fisiología , Sueño/fisiología , Vigilia/fisiología , Adulto , Regiones Antárticas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fotoperiodo , Fotofobia/metabolismo , Fotofobia/fisiopatología , Opsinas de Bastones/metabolismo , Estaciones del Año , Privación de Sueño/metabolismo , Privación de Sueño/fisiopatología , Luz Solar , Adulto Joven
3.
Allergy ; 73(6): 1313-1321, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29319896

RESUMEN

BACKGROUND: Cutaneous exposure to food antigen through impaired skin barrier has been shown to induce epicutaneous sensitization, thereby causing IgE-mediated food allergies. OBJECTIVE: We examined whether skin barrier impairment following epicutaneous sensitization exacerbates food allergies. METHODS: BALB/c mice were epicutaneously sensitized by repeated application of ovalbumin (OVA) to MC903-pretreated ear skin for 48 hours weekly and then intragastrically challenged with OVA. After the first oral challenge, the skin barrier was disrupted with topical application of MC903 or by tape-stripping. Mice were monitored for changes in body temperature and the occurrence of diarrhea after undergoing the second oral challenge. Serum levels of mouse mast cell protease-1 (mmcp1) and OVA-specific IgE, IgG1, IgG2a antibodies and OVA-specific IgA levels in intestinal lavage fluid were measured by ELISA. Tissue accumulation of eosinophils was determined histologically. RESULTS: Epicutaneously sensitized mice developed anaphylaxis after intragastric challenge, as evidenced by diarrhea, decreased body temperature, and increased serum mmcp1 levels. Skin barrier disruption by MC903 treatment or tape-stripping exacerbated allergic reactions induced by oral challenge. MC903 treatment increased serum baseline and postchallenge mmcp1 levels. Topical pretreatment with dexamethasone alleviated allergic reactions that were exacerbated by MC903 treatment. CONCLUSION: Even after eliminating exposure to the antigen, inflammation from skin barrier disruption can exacerbate the severity of food allergy symptoms. Serum baseline mmcp1 levels might be an effective marker for predicting the severity of antigen-induced allergic symptoms.


Asunto(s)
Dermatitis/complicaciones , Hipersensibilidad a los Alimentos/complicaciones , Hipersensibilidad a los Alimentos/patología , Alérgenos/inmunología , Animales , Dermatitis/tratamiento farmacológico , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Femenino , Alimentos/efectos adversos , Hipersensibilidad a los Alimentos/inmunología , Hipersensibilidad a los Alimentos/prevención & control , Glucocorticoides/farmacología , Inmunización , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Ratones , Fenotipo
4.
Genes Immun ; 18(1): 1-7, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27829665

RESUMEN

Associations between human leukocyte antigen (HLA) and susceptibility to systemic autoimmune diseases have been reported. The predisposing alleles are variable among ethnic groups and/or diseases. On the other hand, some HLA alleles are associated with resistance to systemic autoimmune diseases, including systemic sclerosis, systemic lupus erythematosus and rheumatoid arthritis. Interestingly, DRB1*13 alleles are the protective alleles shared by multiple autoimmune diseases. DRB1*13:01 allele is protective in European populations and DRB1*13:02 in Japanese. Because alleles in multiple HLA loci are in strong linkage disequilibrium, it is difficult to determine which of the protective alleles is functionally responsible for the protective effects. Thus far, association studies suggested that DRB1*13:02 represents at least one of the causally associated protective factors against multiple systemic autoimmune diseases in the Japanese population. The protective effect of DRB1*13 alleles appears to overcome the predisposing effect of the susceptible alleles in heterozygous individuals of DRB1*13 and the susceptible allele. A gene dosage effect was observed in the associations of DRB1*13:02 with the protection from systemic autoimmune diseases; thus homozygous individuals are more effectively protected from the systemic autoimmune diseases than heterozygotes. DRB1*13:02 also confers protection against organ-specific autoimmune diseases and some infectious diseases. Several hypotheses can be proposed for the molecular mechanisms of the protection conferred by DRB1*13, some of which can explain the dominant effect of DRB1*13 molecules over the susceptible alleles, but the actual protective function of DRB1*13 requires further study. Understanding of the protective mechanisms of DRB1*13 may lead to the identification of targets for the curative treatment of systemic autoimmune diseases.


Asunto(s)
Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/prevención & control , Cadenas HLA-DRB1/inmunología , Sustancias Protectoras/administración & dosificación , Humanos
5.
Sci Rep ; 5: 15185, 2015 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-26478261

RESUMEN

This study examined the effect of optic nerve disease, hence retinal ganglion cell loss, on non-visual functions related to melanopsin signalling. Test subjects were patients with bilateral visual loss and optic atrophy from either hereditary optic neuropathy (n = 11) or glaucoma (n = 11). We measured melatonin suppression, subjective sleepiness and cognitive functions in response to bright light exposure in the evening. We also quantified the post-illumination pupil response to a blue light stimulus. All results were compared to age-matched controls (n = 22). Both groups of patients showed similar melatonin suppression when compared to their controls. Greater melatonin suppression was intra-individually correlated to larger post-illumination pupil response in patients and controls. Only the glaucoma patients demonstrated a relative attenuation of their pupil response. In addition, they were sleepier with slower reaction times during nocturnal light exposure. In conclusion, glaucomatous, but not hereditary, optic neuropathy is associated with reduced acute light effects. At mild to moderate stages of disease, this is detected only in the pupil function and not in responses conveyed via the retinohypothalamic tract such as melatonin suppression.


Asunto(s)
Glaucoma/metabolismo , Glaucoma/fisiopatología , Luz , Enfermedades del Nervio Óptico/metabolismo , Enfermedades del Nervio Óptico/fisiopatología , Adulto , Estudios de Casos y Controles , Femenino , Glaucoma/diagnóstico , Humanos , Masculino , Melatonina/metabolismo , Persona de Mediana Edad , Enfermedades del Nervio Óptico/diagnóstico , Desempeño Psicomotor , Pupila , Células Ganglionares de la Retina/metabolismo , Opsinas de Bastones/metabolismo , Saliva/metabolismo , Transducción de Señal , Sueño/efectos de la radiación , Visión Ocular , Agudeza Visual , Campos Visuales , Adulto Joven
7.
Rev Med Suisse ; 11(461): 411-7, 2015 Feb 11.
Artículo en Francés | MEDLINE | ID: mdl-25895220

RESUMEN

Giant cell arteritis (GCA) is a subacute/chronic vasculitis and represents the most common form of systemic vasculitis in people over the age of 50 years. The absence of clear and specific diagnostic criteria with the highly variable clinical presentation is a diagnostic challenge requesting a multidisciplinary approach. Yet, GCA is an emergency and the treatment must be initiated very rapidly due to the risk of blindness. This article presents a review of GCA as well as the diagnostic and therapeutic institutional guidelines of the University Hospital of Lausanne.


Asunto(s)
Arteritis de Células Gigantes/tratamiento farmacológico , Arteritis de Células Gigantes/terapia , Algoritmos , Hospitales Universitarios , Humanos , Guías de Práctica Clínica como Asunto , Suiza
8.
Neuroimage ; 101: 547-54, 2014 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-25016138

RESUMEN

Light adaptation is crucial for coping with the varying levels of ambient light. Using high-density electroencephalography (EEG), we investigated how adaptation to light of different colors affects brain responsiveness. In a within-subject design, sixteen young participants were adapted first to dim white light and then to blue, green, red, or white bright light (one color per session in a randomized order). Immediately after both dim and bright light adaptation, we presented brief light pulses and recorded event-related potentials (ERPs). We analyzed ERP response strengths and brain topographies and determined the underlying sources using electrical source imaging. Between 150 and 261 ms after stimulus onset, the global field power (GFP) was higher after dim than bright light adaptation. This effect was most pronounced with red light and localized in the frontal lobe, the fusiform gyrus, the occipital lobe and the cerebellum. After bright light adaptation, within the first 100 ms after light onset, stronger responses were found than after dim light adaptation for all colors except for red light. Differences between conditions were localized in the frontal lobe, the cingulate gyrus, and the cerebellum. These results indicate that very short-term EEG brain responses are influenced by prior light adaptation and the spectral quality of the light stimulus. We show that the early EEG responses are differently affected by adaptation to different colors of light which may contribute to known differences in performance and reaction times in cognitive tests.


Asunto(s)
Adaptación Ocular/fisiología , Cerebelo/fisiología , Corteza Cerebral/fisiología , Percepción de Color/fisiología , Electroencefalografía/métodos , Potenciales Evocados Visuales/fisiología , Adulto , Femenino , Humanos , Masculino , Distribución Aleatoria , Factores de Tiempo , Adulto Joven
10.
Genes Immun ; 14(8): 527-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23985571

RESUMEN

Interferon regulatory factor 5 (IRF5) and signal transducer and activator of transcription 4 (STAT4) are shared susceptibility genes for various autoimmune diseases. In this study, we investigated whether these genes also contribute to susceptibility to anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) in a Japanese population. A case-control study was carried out on IRF5 rs10954213 and STAT4 rs7574865 in 232 Japanese myeloperoxidase (MPO)-ANCA-positive AAV patients, including 177 microscopic polyangiitis and 710 healthy controls. IRF5 rs10954213G was significantly increased in MPO-ANCA-positive AAV (additive model, P=0.023, odds ratio=1.27, 95% confidence interval=1.03-1.57). The risk allele was previously shown to be associated with lower mRNA level of IRF5. On the other hand, significant association of STAT4 rs7574865T with AAV was not detected. These observations suggested that IRF5 may contribute to susceptibility to MPO-ANCA-positive AAV in a Japanese population.


Asunto(s)
Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/genética , Factores Reguladores del Interferón/genética , Peroxidasa/metabolismo , Polimorfismo de Nucleótido Simple , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Japón , Masculino , Poliangitis Microscópica/genética , Persona de Mediana Edad , Peroxidasa/genética , Factor de Transcripción STAT4/genética
11.
Lupus ; 22(5): 497-503, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23554038

RESUMEN

SH2D1A, also known as signaling lymphocytic activation molecule (SLAM)-associated protein (SAP), is an adaptor protein. Recently, it was reported that SAP deficient mice were protected from systemic lupus erythematosus (SLE). In this study, we postulated SH2D1A gene to be a candidate susceptibility gene for SLE and analyzed its association with SLE. A case-control association study was conducted on 5 tag single nucleotide polymorphisms (SNPs) in SH2D1A region in 506 Japanese female SLE patients and 330 healthy female controls. The luciferase assay was performed to determine the functional role of the SNP associated with SLE. One SNP in the intron 2, rs2049995, showed association with SLE (p=0.0110, odds ratio (OR) 1.97, 95% confidence interval (CI) 1.16-3.34, under the dominant model). The association of rs2049995 seemed to be stronger in the subset with the age of onset less than 20 years (p=0.0067, OR 2.65, 95% CI 1.28-5.46). Functional evaluation of rs2049995 showed that reporter gene activity was increased 1.9-fold for the susceptible allele compared with the resistant allele. An intronic SNP of SH2D1A is associated with SLE.


Asunto(s)
Péptidos y Proteínas de Señalización Intracelular/genética , Lupus Eritematoso Sistémico/genética , Adulto , Pueblo Asiatico , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Intrones , Japón , Células Jurkat , Leucocitos Mononucleares/metabolismo , Leucocitos Mononucleares/patología , Luciferasas , Lupus Eritematoso Sistémico/metabolismo , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Proteína Asociada a la Molécula de Señalización de la Activación Linfocitaria
12.
Clin Exp Immunol ; 172(1): 44-53, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23480184

RESUMEN

To identify and characterize anti-citrullinated glucose-6-phosphate isomerase (GPI) peptide antibodies in patients with rheumatoid arthritis (RA). Nine GPI arginine-bearing peptides in human GPI protein were selected and cyclic citrullinated GPI peptides (CCG-1-9) were constructed. Samples were obtained from RA (n = 208), systemic lupus erythematosus (SLE) (n = 101), Sjögren's syndrome (SS; n = 101) and healthy controls (n = 174). Antibodies against CCG-1-9 were measured, and anti-citrullinated α-enolase-1 (CEP-1), -cyclic citrullinated peptides (CCP) and -GPI proteins antibodies were also examined. Patients with RA were genotyped for HLA-DRB1. The numbers of shared epitope (SE) alleles were counted and compared with those of the autoantibodies. Rabbit GPI was citrullinated with rabbit peptidylarginine deiminase and immunoblot analysis of RA sera performed. The levels of autoantibodies were compared before and after treatment with TNF antagonists in 58 RA patients. Anti-CCG-2, -4 and -7 antibodies were detected in 25·5, 33·2 and 37·0% patients with RA, respectively, and these antibodies were very specific for RA (specificity, 98·1-99·7%). Altogether, 44·2, 86·1 and 13·9% of RA sera were positive for anti-CEP-1, -CCP and -GPI protein antibodies, respectively. Anti-CCG-2, -4 and -7 antibodies were correlated with anti-CCP and anti-CEP-1 antibodies and with the presence of HLA-DRB1 SE alleles. Citrullinated GPI protein was detected using RA sera. Treatment with tumour necrosis factor antagonists reduced significantly the levels of anti-CCG-2 and -7 but not of anti-CEP-1 antibodies. This is the first report documenting the presence of anti-CCG antibodies in RA. Anti-CCG-2 and -7 antibodies could be considered as markers for the diagnosis of RA and its disease activity.


Asunto(s)
Artritis Reumatoide/inmunología , Autoanticuerpos/inmunología , Epítopos , Cadenas HLA-DRB1/inmunología , Lupus Eritematoso Sistémico/inmunología , Síndrome de Sjögren/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alelos , Animales , Especificidad de Anticuerpos , Artritis Reumatoide/sangre , Autoanticuerpos/sangre , Estudios de Casos y Controles , Citocinas/sangre , Citocinas/inmunología , Femenino , Expresión Génica , Glucosa-6-Fosfato Isomerasa/sangre , Glucosa-6-Fosfato Isomerasa/inmunología , Cadenas HLA-DRB1/sangre , Cadenas HLA-DRB1/genética , Humanos , Inmunofenotipificación , Lupus Eritematoso Sistémico/sangre , Masculino , Persona de Mediana Edad , Péptidos Cíclicos/sangre , Péptidos Cíclicos/inmunología , Conejos , Índice de Severidad de la Enfermedad , Síndrome de Sjögren/sangre
14.
Lupus ; 21(8): 890-5, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22433914

RESUMEN

Interferon regulatory factor 7 (IRF7) has an essential role in the production of type I interferon. Although recent studies detected association of a single nucleotide polymorphism (SNP) rs4963128 in PHD and ring finger domains 1 (PHRF1)/KIAA1542, located closely to IRF7, and IRF7 rs1131665 (glutamine (Gln) 412 arginine (Arg)) with systemic lupus erythematosus (SLE), causal variants have not been established. In this study, we resequenced exons and introns of IRF7 to screen for all common polymorphisms, and examined whether they were associated with SLE in 416 Japanese patients with SLE and 505 healthy controls. We also tested whether the association of PHRF1 rs4963128 with SLE was replicated in a Japanese population. None of the IRF7 polymorphisms was associated with SLE. PHRF1 rs4963128T was not significantly associated with occurrence of SLE either; however, this allele was significantly increased in SLE with anti-Sm antibodies (6.8%) as compared with healthy controls (3.1%, P = 0.014, odds ratio [OR] 2.31) and SLE without anti-Sm antibodies (3.3%, P =0.041, OR 2.12). This allele was also increased in SLE with renal disorder (5.1%) as compared with those without renal disorder (2.4%, P = 0.047, OR 2.17). These results confirmed recently reported association of PHRF1 rs4963128T with anti-Sm antibody positive SLE in African-American populations, and supported the role of PHRF1-IRF7 region in the genetics of SLE.


Asunto(s)
Pueblo Asiatico/genética , Factor 7 Regulador del Interferón/genética , Lupus Eritematoso Sistémico/genética , Polimorfismo Genético , Dominios RING Finger/genética , Alelos , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Exones , Humanos , Intrones , Japón , Lupus Eritematoso Sistémico/inmunología , Análisis de Secuencia de ADN
15.
Leukemia ; 24(5): 914-23, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20376080

RESUMEN

The transcription factor CCAAT enhancer-binding protein alpha (C/EBPalpha) has an important role in granulopoiesis. The tumor suppressor function of C/EBPalpha is shown by the findings that loss of expression or function of C/EBPalpha in leukemic blasts contributes to a block in myeloid cell differentiation and to leukemia. C/EBPalpha mutations are found in around 9% of acute myeloid leukemia (AML) patients. The mechanism by which the mutant form of C/EBPalpha (C/EBPalpha-p30) exerts a differentiation block is not well understood. By using a proteomic screen, we have recently reported PIN1 as a target of C/EBPalpha-p30 in AML. In the present study, we show that C/EBPalpha-p30 induces PIN1 expression. We observed elevated PIN1 expression in leukemic patient samples. Induction of C/EBPalpha-p30 results in recruitment of E2F1 in the PIN1 promoter. We show that the inhibition of PIN1 leads to myeloid differentiation in primary AML blasts with C/EBPalpha mutations. Overexpression of PIN1 in myeloid cells leads to block of granulocyte differentiation. We also show that PIN1 increases the stability of the c-Jun protein by inhibiting c-Jun ubiquitination, and c-Jun blocks granulocyte differentiation mediated by C/EBPalpha. Our data suggest that the inhibition of PIN1 could be a potential strategy of treating AML patients with C/EBPalpha mutation.


Asunto(s)
Proteína alfa Potenciadora de Unión a CCAAT/fisiología , Diferenciación Celular , Granulocitos/citología , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Leucemia Mieloide Aguda/metabolismo , Isomerasa de Peptidilprolil/metabolismo , Biomarcadores de Tumor , Western Blotting , Diferenciación Celular/efectos de los fármacos , Inmunoprecipitación de Cromatina , Citometría de Flujo , Perfilación de la Expresión Génica , Granulocitos/metabolismo , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/genética , Células K562 , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Mutación/genética , Peptidilprolil Isomerasa de Interacción con NIMA , Análisis de Secuencia por Matrices de Oligonucleótidos , Isomerasa de Peptidilprolil/antagonistas & inhibidores , Isomerasa de Peptidilprolil/genética , Regiones Promotoras Genéticas , Proteómica , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Interferente Pequeño/farmacología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Ubiquitina/metabolismo
17.
Kyobu Geka ; 62(1): 41-4, 2009 Jan.
Artículo en Japonés | MEDLINE | ID: mdl-19195185

RESUMEN

The results of combined surgery for ischemic cardiomyopathy were reviewed focusing on the selection of operative procedures. Left ventricular volume reduction was performed in 33 patients. Hospital mortality was 17% in Dor procedure (n=24), 20% in Batista operation (n=5) and 0% in over-lapping method (n=4). Procedures should be selected according to left ventricular wall area to be excluded. Mitral valve plasty was performed in 50 patients, and early and late results of our original "papillary muscle sandwich plasty" (n=27) was superior to those of other conventional procedures (n=23). In "sandwich plasty", the papillary muscle heads of the anterior and the posterior mitral valve leaflets are approximated using tefron-pledgeted 3-0 ticron suture at the anterolateral and posteromedian commissural portions, respectively. In conclusion, active combined surgery is necessary for the treatment of ischemic cardiomyopathy.


Asunto(s)
Cardiomiopatías/cirugía , Ventrículos Cardíacos/cirugía , Válvula Mitral/cirugía , Isquemia Miocárdica/cirugía , Anciano , Anciano de 80 o más Años , Procedimientos Quirúrgicos Cardíacos/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad
18.
Neuroscience ; 160(1): 61-8, 2009 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-19232380

RESUMEN

Gap junctional communication plays an important role in various models of brain pathology, but the changes of gap junctions in Parkinsonism are still not understood. In this study, we show that a major gap junctional protein, connexin43 (Cx43), in astrocytes is enhanced both in a rat Parkinson's disease (PD) model induced with rotenone, a widely used pesticide that inhibits mitochondrial complex I, and in vitro in cultured astrocytes stimulated with rotenone. Enhancement of Cx43 protein levels in rotenone-treated cultured astrocytes occurred in parallel with an increase in gap junctional intercellular communication, but was not accompanied with an increase in Cx43 mRNA levels. Furthermore, the rotenone-induced increase of Cx43 protein levels both in vitro and in vivo was associated with increased levels of phosphorylated Cx43, which is required for gap junctional intercellular communication. In our rat PD model, phosphorylated Cx43 was selectively enhanced in the basal ganglia regions, which contain DA neurons or their terminal areas. The increase of Cx43 levels was lower in the substantia nigra pars compacta and the striatum than in the substantia nigra pars reticulata and the globus pallidus. Our findings indicate that modulation of Cx43 protein, and consequently gap junctional cellular communication, in astrocytes may play an important role in PD pathology.


Asunto(s)
Astrocitos/metabolismo , Encéfalo/metabolismo , Conexina 43/metabolismo , Enfermedad de Parkinson/metabolismo , Animales , Western Blotting , Comunicación Celular , Células Cultivadas , Modelos Animales de Enfermedad , Técnica del Anticuerpo Fluorescente , Uniones Comunicantes/metabolismo , Fosforilación , ARN Mensajero/metabolismo , Distribución Aleatoria , Ratas , Ratas Endogámicas Lew , Ratas Wistar , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rotenona , Transducción de Señal
19.
Sci Total Environ ; 407(4): 1383-90, 2009 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-19033080

RESUMEN

Long-term application of phosphate fertilizers causes accumulation of U in the surface soil of agricultural fields. We investigated the soil constituents that contribute to the accumulation of U by using chemical extraction methods. Surface soil samples were obtained from upland fields, pastures, and paddy fields cultivated without any phosphate fertilizer (control site), with NPK fertilizer (NPK site), and with both NPK fertilizer and compost (NPK+compost site) for more than 20 years. In addition to the total U (Ut) concentration in soil, the concentrations of pyrophosphate- and acid oxalate-extractable U were determined as a measure of U associated with soil organic matter and poorly crystalline Fe/Al minerals in soil, respectively. The total, pyrophosphate-extractable, and acid oxalate-extractable U concentrations were higher in the soil obtained from the NPK and NPK+compost sites than in that obtained from the control site. The difference in the U concentrations between the NPK or NPK+compost site and the control site corresponded with the increased U concentration observed after the application of the phosphate fertilizer or both the fertilizer and compost. In the upland field and pasture soil, the increase in pyrophosphate-extractable U was 83-94% of that in Ut. On the other hand, the increase in acid oxalate-extractable U was 44-58% of that in Ut in the upland field and pasture soil, but it was almost equivalent to the increase in Ut in the paddy soil with NPK. In conclusion, most of the phosphate fertilizer-derived U was either incorporated into the soil organic matter or poorly crystalline Fe/Al minerals in the surface soil of agricultural fields. Thus, soil organic matter is an important pool of U in upland field and pasture soil, whereas poorly crystalline Fe/Al minerals are important pools of U in paddy soil experiencing alternating changes in redox conditions.


Asunto(s)
Fertilizantes , Fosfatos/química , Contaminantes del Suelo/química , Suelo/análisis , Uranio/química , Agricultura/métodos , Contaminantes del Suelo/análisis , Uranio/análisis
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