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1.
Skeletal Radiol ; 41(9): 1087-92, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22234561

RESUMEN

OBJECTIVE: Quantitative MR imaging techniques of degenerative cartilage have been reported as useful indicators of degenerative changes in cartilage extracellular matrix, which consists of proteoglycans, collagen, non-collagenous proteins, and water. Apparent diffusion coefficient (ADC) mapping of cartilage has been shown to correlate mainly with the water content of the cartilage. As the water content of the cartilage in turn correlates with its viscoelasticity, which directly affects the mechanical strength of articular cartilage, ADC can serve as a potentially useful indicator of the mechanical strength of cartilage. The aim of this study was to investigate the correlation between ADC and viscoelasticity as measured by indentation testing. MATERIALS AND METHODS: Fresh porcine knee joints (n = 20, age 6 months) were obtained from a local abattoir. ADC of porcine knee cartilage was measured using a 3-Tesla MRI. Indentation testing was performed on an electromechanical precision-controlled system, and viscosity coefficient and relaxation time were measured as additional indicators of the viscoelasticity of cartilage. The relationship between ADC and viscosity coefficient as well as that between ADC and relaxation time were assessed. RESULTS: ADC was correlated with relaxation time and viscosity coefficient (R(2) = 0.75 and 0.69, respectively, p < 0.01). The mean relaxation time values in the weight-bearing and non-weight-bearing regions were 0.61 ± 0.17 ms and 0.14 ± 0.08 ms, respectively. CONCLUSIONS: This study found a moderate correlation between ADC and viscoelasticity in the superficial articular cartilage. Both molecular diffusion and viscoelasticity were higher in weight bearing than non-weight-bearing articular cartilage areas.


Asunto(s)
Cartílago Articular/anatomía & histología , Cartílago Articular/fisiología , Imagen de Difusión por Resonancia Magnética/métodos , Soporte de Peso/fisiología , Animales , Módulo de Elasticidad/fisiología , Técnicas In Vitro , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estadística como Asunto , Porcinos , Viscosidad
2.
J Environ Radioact ; 232: 106565, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33714078

RESUMEN

The Kanyakumari coastal area in the southernmost part of Tamil Nadu, India is a well-known natural high background radiation area due to the abundance of monazite in beach placer deposits. In the present study, the concentrations of major oxides, rare earth elements (REEs), Th and U were measured to understand geochemical characteristics of these monazite sands. Based on the ambient dose rate, 23 locations covering an area of about 60 km along the coast were selected for sample collection. The concentrations of U and Th ranged from 1.1 to 737.8 µg g-1 and 25.2-12250.6 µg g-1, respectively. The Th/U ratio ranged from 2.2 to 61.6, which clearly indicated that Th was the dominant contributing radionuclide to the enhanced natural radioactivity in this coastal region. The chondrite-normalized REEs pattern of the placer deposits showed enrichment in light REEs and depletion in heavy REEs with a negative Eu anomaly that indicated the monazite sands were derived from granite, charnockite, and granitoid rocks from the Nagercoil and the Trivandrum Blocks of the Southern Granulite Terrain.


Asunto(s)
Metales de Tierras Raras , Monitoreo de Radiación , Uranio , Radiación de Fondo , India , Metales de Tierras Raras/análisis , Arena , Torio/análisis , Uranio/análisis
3.
Radiat Prot Dosimetry ; 184(3-4): 500-503, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31330022

RESUMEN

Absorbed dose rates in air were measured for the whole area of the Kanto region in 2015, 2016 and 2017 (n = 31 147). The mean absorbed dose rates in air for each prefecture measured by car-borne surveys were from 44 to 67 nGy h-1 (13-289 nGy h-1). The absorbed dose rate in air from artificial radionuclides (134Cs + 137Cs) measured by fixed-point observation (n = 507) was from 1 to 14 nGy h-1 (0-105 nGy h-1), and meaning that the contribution ratios of 134Cs and 137Cs were 3-22%. The deposited location of artificial radionuclides was less than 1000 m from ground level and depended on the topography, wind direction and precipitation field.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Radioisótopos de Cesio/análisis , Accidente Nuclear de Fukushima , Plantas de Energía Nuclear , Monitoreo de Radiación/métodos , Ceniza Radiactiva/análisis , Humanos , Japón , Dosis de Radiación
4.
Radiat Prot Dosimetry ; 184(3-4): 409-412, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31038715

RESUMEN

A preliminary study was carried out to determine the radioactivity concentration of 232Th, 226Ra and 40K in beach placer sands from 13 locations along the coast line of Tamil Nadu state, India. The ambient dose rates varied from 9 to 467 nGy h-1. The activity concentrations of radionuclide 232Th, 226Ra and 40K ranged from 5.2 to 683 Bq kg-1, 13 to 198 Bq kg-1 and 107 to 421 Bq kg-1, respectively. The annual effective dose rate ranges from 27 to 620 µSv y-1 and was higher at seven beaches in comparison to the UNSCEAR annual worldwide average value.


Asunto(s)
Radioisótopos de Potasio/análisis , Exposición a la Radiación/análisis , Contaminantes Radiactivos del Suelo/análisis , Torio/análisis , Uranio/análisis , Humanos , India , Monitoreo de Radiación , Arena
5.
Radiat Prot Dosimetry ; 184(3-4): 328-333, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31038704

RESUMEN

We have recently have developed an in-situ multiple-channel depth distribution spectrometer (DDS) that can easily acquire on-site measurements of the depth distribution of specific radioactivities of Cs-134 and Cs-137 underground. Despite considerable improvements in the hardware developed for this device, the quantitative method for determining of radioactivities with this DDS device cannot yet achieve satisfactory performance for practical use. For example, this method cannot discriminate each γ-ray spectra of Cs-134 and Cs-137 acquired by the 20 thallium-doped caesium iodine CsI(Tl) scintillation crystal detectors of the DDS device from corresponding depth levels of underground soil. Therefore, we have applied deep learning neural network (DLNN) as a novel radiation measurement technique to discriminate the spectra and to determine the specific radioactivities of Cs-134 and Cs-137. We have developed model soil layers on a virtual space in Monte-Carlo based PHITS simulations and transported γ-ray radiation generated from a particular single soil layer or multiple layers as radiation sources; next, we performed PHITS calculations of those specific radioactivity measurements for each soil layer using DDS device based on machine learning via the DLNN algorithm. In this study, we obtained informative results regarding the feasibility of the proposal innovative radiation measurement method for further practical use in on-site applications.


Asunto(s)
Algoritmos , Radioisótopos de Cesio/análisis , Simulación por Computador , Conteo por Cintilación/instrumentación , Contaminantes Radiactivos del Suelo/análisis , Espectrometría gamma , Estudios de Factibilidad , Humanos , Monitoreo de Radiación
6.
J Environ Radioact ; 195: 40-53, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30243099

RESUMEN

In this study, radiocesium and 40K analysis were accomplished for samples of riverbed sediments and floodplain deposits collected from five rivers in the vicinity (<20 km) of the damaged Fukushima Daiichi Nuclear Power Plant after seven years of the accident. Sediment particle size distribution and major oxide content were determined also for six selected samples to understand the retention and migration process of radiocesium in river environments. The radiocesium activity concentration varied from 103 ±â€¯6 Bq·kg-1 to 22,000 ±â€¯500 Bq·kg-1 in riverbed sediments and from 92 ±â€¯5 Bq·kg-1 to 117,000 ±â€¯2000 Bq·kg-1 in floodplain deposits. The 134Cs/137Cs ratio (decay corrected to 15 March 2011) was 1.02 in the both samples. Compared to monitoring results in 2011, it was proved that the radiocesium distribution pattern had been changed remarkably during seven years. The radiocesium was primarily attached to fine clay particles but its sorption on sand and coarse sand particles was also considerable. The sorption process of radiocesium was not affected by the presence of water and moreover, after seven years of the Fukushima accident, a significant radiocesium migration cannot be expected without particle migration. Consequently, radiocesium will remain for a long time in the river environments and its redistribution is mainly affected by the erosion process of the sediments. The average 40K activity concentration of riverbed sediment and floodplain deposit samples was 640 ±â€¯152 Bq·kg-1 changing from 319 ±â€¯18 Bq·kg-1 to 916 ±â€¯41 Bq·kg-1. In the river estuary zones, significant activity concentration decrements were observed for both radionuclides. This suggests that seawater intrusion has a decreasing effect on both natural and artificial radionuclides via wash-out of particulate radiocesium and 40K, and desorption of these radionuclides, but to reveal the detail of this process further investigations are required. The analysis of 40K can help in a simple and easy way to reveal the mineral composition differences of sediment samples.


Asunto(s)
Radioisótopos de Cesio/análisis , Accidente Nuclear de Fukushima , Monitoreo de Radiación , Contaminantes Radiactivos del Agua/análisis , Estuarios , Sedimentos Geológicos/química , Japón , Ríos/química
7.
J Inherit Metab Dis ; 30(4): 593-5, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17616848

RESUMEN

We report our experience in developing and implementing a training programme aimed at introducing neonatal screening to health care professionals in developing countries. It was originally envisioned as a 10-year programme but was later extended to 15. Our institute initially began offering the training course in neonatal screening on an annual basis in 1990, under the auspices of the Japan International Cooperation Agency (JICA). The aims of the programme were to enhance the participants' technical knowledge and skills, as well as deepen their understanding of the principles involved in neonatal screening. Over the 15 years that the programme ran, up to March 2005, a total of 130 participants originating from 36 countries completed the course, the participants comprising some 85 paediatricians, 4 obstetricians, 34 biochemists and 7 administrative officers or public health specialists, a number of whom have subsequently implemented neonatal screening programmes in their respective institutes, regions or countries. Having thus completed the initial 15-year phase of the training course, after a thorough evaluation we initiated the second phase of our international training and support programme for neonatal screening in 2006. With the objective of supporting the establishment of a neonatal screening system for congenital hypothyroidism, the new programme consists of not only specialist training in Japan but also financial and technical assistance for helping to establish neonatal screening in the participants' respective countries.


Asunto(s)
Hipotiroidismo Congénito/genética , Países en Desarrollo , Educación Médica Continua , Tamizaje Neonatal/métodos , Tamizaje Neonatal/normas , Hipotiroidismo Congénito/diagnóstico , Humanos , Recién Nacido , Cooperación Internacional , Japón , Desarrollo de Programa , Salud Pública , Factores de Tiempo
8.
J Inherit Metab Dis ; 30(4): 609, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17574536

RESUMEN

BACKGROUND: Neonatal screening for congenital disorders like phenylketonuria (PKU), congenital hypothyroidism (CH) and congenital adrenal hyperplasia (CAH) is generally performed in dried blood spots on filter paper. The analytes of interest for testing for PKU, CH and CAH are phenylalanine, thyrotropin (TSH) and 17alpha-hydroxyprogesterone (17OHP), respectively. The International Society for Neonatal Screening (ISNS) decided to prepare a combined reference preparation for the three analytes on filter paper Schleicher & Schuell #903, Whatman BFC180 and Toyo Roshi 545. This 'First ISNS Reference Preparation for Neonatal Screening for TSH, phenylalanine and 17OHP in blood spots' (1st ISNS-RPNS) has been prepared by the RIVM (Bilthoven). METHOD: The number of filter paper cards prepared, each with two sets of six blood spot calibrators, was 480, 42 and 69 for Schleicher & Schuell #903, Whatman BFC180 and Toyo Roshi 545, respectively. The volume of blood dispensed was 50 microl. The range of concentrations for TSH was 1-121 mIU/L blood, for phenylalanine 65-865 micromol/L blood and for 17OHP 2.2-302 nmol/L blood. RESULTS: The linearity of the blood spot calibrators and the homogeneity of the batch (only tested for Schleicher & Schuell) were good. The differences between the three filter papers were small: i.e. the potency of the ISNS-RPNS on Whatman and Toyo Roshi in terms of Schleicher & Schuell was between 0.98 and 1.09 for the three analytes. CONCLUSION: The 1st ISNS-RPNS for TSH, phenylalanine and 17OHP can be said to be suitable as formal reference preparation and as a source for (re)calibrating kit calibrators.


Asunto(s)
17-alfa-Hidroxiprogesterona/sangre , Análisis Químico de la Sangre/normas , Tamizaje Neonatal/instrumentación , Tamizaje Neonatal/métodos , Tamizaje Neonatal/normas , Fenilalanina/sangre , Fenilcetonurias/sangre , Tirotropina/sangre , Recolección de Muestras de Sangre , Calibración , Diseño de Equipo , Humanos , Recién Nacido , Papel , Control de Calidad , Análisis de Regresión , Reproducibilidad de los Resultados
9.
Radiat Prot Dosimetry ; 167(1-3): 231-4, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25944962

RESUMEN

The monitoring of absorbed dose rate in air has been carried out continually at various locations in metropolitan Tokyo after the accident of the Fukushima Daiichi Nuclear Power Plant. While the data obtained before the accident are needed to more accurately assess the effects of radionuclide contamination from the accident, detailed data for metropolitan Tokyo obtained before the accident have not been reported. A car-borne survey of the absorbed dose rate in air in metropolitan Tokyo was carried out during August to September 2003. The average absorbed dose rate in air in metropolitan Tokyo was 49±6 nGy h(-1). The absorbed dose rate in air in western Tokyo was higher compared with that in central Tokyo. Here, if the absorbed dose rate indoors in Tokyo is equivalent to that outdoors, the annual effective dose would be calculated as 0.32 mSv y(-1).


Asunto(s)
Absorción de Radiación , Contaminantes Radiactivos del Aire/análisis , Accidente Nuclear de Fukushima , Exposición a la Radiación/análisis , Monitoreo de Radiación/métodos , Ceniza Radiactiva/análisis , Dosis de Radiación , Tokio
10.
Radiat Prot Dosimetry ; 167(1-3): 219-22, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25956780

RESUMEN

Due to releases of radionuclides in the Fukushima Daiichi Nuclear Power Plant accident, radiocesium ((134)Cs and (137)Cs) has been incorporated into large varieties of plant species and soil types. There is a possibility that radiocesium taken into plants is being diffused by pollen. Radiocesium concentrations in cedar pollen have been measured in Ome City, located in the Okutama area of metropolitan Tokyo, for the past 3 y. In this research, the variation of radiocesium concentrations was analysed by comparing data from 2011 to 2014. Air dose rates at 1 m above the ground surface in Ome City from 2011 to 2014 showed no significant difference. Concentration of (137)Cs contained in the cedar pollen in 2012 was about half that in 2011. Between 2012 and 2014, the concentration decreased by approximately one-fifth, which was similar to the result of a press release distributed by the Japanese Ministry of Agriculture, Forestry and Fisheries.


Asunto(s)
Cedrus/química , Isótopos de Cesio/análisis , Accidente Nuclear de Fukushima , Polen/química , Monitoreo de Radiación/métodos , Contaminantes Radiactivos del Suelo/análisis , Contaminantes Radiactivos del Aire/análisis , Bioensayo/métodos , Japón , Dosis de Radiación , Ceniza Radiactiva/análisis , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Análisis Espacio-Temporal
11.
FEBS Lett ; 442(1): 83-8, 1999 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-9923610

RESUMEN

The nef gene of human and simian immunodeficiency virus is a key factor in acquired immunodeficiency syndrome pathogenesis and virus replication. Several Nef-induced phenomena, including the down-regulation of CD4 molecule, have been previously reported. In this study, we have identified and cloned a novel cellular protein Naf1 (Nef-associated factor 1), which associated with Nef in the yeast two-hybrid system and pull-down assay. The Naf1 gene generates two isoforms (Naf1alpha and beta) containing four coiled-coil structures. The Naf1 mRNA is ubiquitously expressed in human tissues with strong expression in peripheral blood lymphocytes and spleen. Naf1 overexpression increased cell surface CD4 expression. Nef suppressed this Naf1-induced augmentation of CD4 expression, providing a novel mode of Nef action in CD4 down-regulation.


Asunto(s)
Antígenos CD4/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Productos del Gen nef/metabolismo , VIH-1/genética , Secuencia de Aminoácidos , Secuencia de Bases , Línea Celular , Membrana Celular/inmunología , Membrana Celular/metabolismo , Clonación Molecular , ADN Complementario/genética , Regulación hacia Abajo , Femenino , Expresión Génica , Productos del Gen nef/genética , Genes nef , VIH-1/patogenicidad , VIH-1/fisiología , Humanos , Masculino , Datos de Secuencia Molecular , Embarazo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Saccharomyces cerevisiae/genética , Distribución Tisular , Productos del Gen nef del Virus de la Inmunodeficiencia Humana
12.
Viral Immunol ; 12(1): 57-66, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10333243

RESUMEN

We generated a rat monoclonal antibody (mAb W#10) with the ability to neutralize human immunodeficiency virus type 1IIIB (HIV-1IIIB) infection. The epitope recognized by mAb W#10 was defined as R-I-Q-R-G-P-G by enzyme-linked immunosorbent assay (ELISA) with the use of synthetic peptides. The filamentous phage clones displaying random 15-amino-acid peptides on the amino terminus of the pIII coat protein reacting with mAb W#10 were identified with affinity and immunological selection procedures. Thirteen out of 16 selected phage clones contained the G-X-G-R-X-F sequence in the coat protein region representing significant homology to a part of conserved G-P-G-R-A-F sequence in the V3 loop of various HIV-1 strains. In addition, the phage clones included the G-X-G sequence in the sequence detected by synthetic peptides as the recognition site. The selected phage clones were stained by mAb W#10 specifically and were able to compete with mAb binding to cells expressing viral antigens.


Asunto(s)
Anticuerpos Monoclonales/química , Mapeo Epitopo/métodos , VIH-1/inmunología , Biblioteca de Péptidos , Péptidos/síntesis química , Péptidos/inmunología , Secuencia de Aminoácidos , Animales , Sitios de Unión de Anticuerpos , Células Cultivadas , Colifagos/genética , Colifagos/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , Riñón , Datos de Secuencia Molecular , Pruebas de Neutralización , Mapeo Peptídico , Péptidos/análisis , Ratas
13.
AIDS Res Hum Retroviruses ; 16(16): 1603-6, 2000 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11080798

RESUMEN

Human T cell leukemia virus type 1 (HTLV-1) Tax protein transforms primary human T cells in vitro. We previously showed that Tax induces the expression of various family members of the transcription factor AP-1 such as c-Jun, JunD, c-Fos, and Fra-1 at the mRNA level in T cells. In this study, we have examined the ability of Tax to activate transcription through the AP-1-binding site (AP-1 site). A transient transfection study showed that Tax can activate transcription through the AP-1-binding site in a human T cell line, whereas any combination of AP-1 proteins did so much less than Tax, indicating that the activation of the AP-1 site by Tax may require a mechanism other than the induction of AP-1 mRNA. Fresh peripheral blood leukemia cells of all surveyed ATL patients displayed constitutive AP-1 DNA-binding activity, whereas no normal individuals did. However, the HTLV-1 genes, including tax, are not significantly expressed in fresh leukemia cells from ATL patients. Our present results suggest that activation of AP-1 occurs through Tax-dependent and -independent mechanisms in HTLV-1-infected T cells, which may play some roles in dysregulated phenotypes of HTLV-1-infected cells.


Asunto(s)
Productos del Gen tax/metabolismo , Virus Linfotrópico T Tipo 1 Humano/metabolismo , Leucemia-Linfoma de Células T del Adulto/virología , Linfocitos T/virología , Factor de Transcripción AP-1/metabolismo , Animales , Línea Celular Transformada , Transformación Celular Viral , Virus Linfotrópico T Tipo 1 Humano/genética , Virus Linfotrópico T Tipo 1 Humano/inmunología , Humanos , Leucemia-Linfoma de Células T del Adulto/metabolismo , Ratones , Linfocitos T/metabolismo , Activación Transcripcional
14.
J Biochem ; 123(5): 968-77, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9562633

RESUMEN

We have studied the biosynthesis and intracellular transport of tissue-nonspecific alkaline phosphatase (TNSALP) transiently expressed in COS-1 cells. Mutations were introduced into TNSALP to examine the effects of a single amino acid substitution on the activity and biosynthesis of TNSALP. The cells expressing wild-type TNSALP exhibited more than 200-fold higher alkaline phosphatase activity than untransfected ones. Pulse-chase experiments showed that TNSALP was synthesized as a 66-kDa endoglucosaminidase H (Endo H)-sensitive form and converted to EndoH-resistant forms with heterogenous molecular masses ( approximately 80 kDa), which finally appeared on the cell surface as judged by digestion with phosphatidylinositol-specific phospholipase C (PI-PLC). In contrast, a TNSALP with a Glu218-->Gly mutation exhibited no phosphatase activity at all and the 66-kDa Endo H-sensitive form was the only molecular species throughout the chase in the transfected cells. In accordance with this finding, digestion with PI-PLC and immunofluorescence observation confirmed that this mutant was never expressed on the cell surface. Another mutant with a Ala162-->Thr substitution, which naturally occurs in association with a lethal hypophosphatasia, exhibited a low activity and only a small fraction of the 66-kDa form acquired Endo-H resistance and reached the cell surface. Since the wild-type and the mutant TNSALPs were labeled with [3H]ethanolamine, a component of glycosylphosphatidylinositol (GPI), it is unlikely that the impaired intracellular transport of the two mutants is due to a failure in their modification by GPI. Interestingly, the 66-kDa Endo H-sensitive form of the TNSALP mutants but not that of the wild-type, was found to form an interchain disulfide-bonded high-molecular-mass aggregate within the cells. These results suggest that impaired intracellular transport of the TNSALP (Ala162-->Thr) molecule caused by its aggregation is the molecular basis for the lethal hypophosphatasia carrying this mutation.


Asunto(s)
Alanina/genética , Fosfatasa Alcalina/metabolismo , Hipofosfatasia/genética , Líquido Intracelular/metabolismo , Isoenzimas/metabolismo , Mutación , Treonina/genética , Fosfatasa Alcalina/biosíntesis , Fosfatasa Alcalina/química , Fosfatasa Alcalina/genética , Sustitución de Aminoácidos , Animales , Transporte Biológico , Células COS , Retículo Endoplásmico/enzimología , Técnica del Anticuerpo Fluorescente , Glicosilfosfatidilinositoles/química , Hexosaminidasas/metabolismo , Isoenzimas/biosíntesis , Isoenzimas/química , Isoenzimas/genética , Manosil-Glicoproteína Endo-beta-N-Acetilglucosaminidasa
15.
Microsc Res Tech ; 41(4): 313-22, 1998 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-9633949

RESUMEN

Woven bone induced by direct injection of basic fibroblast growth factor (bFGF) into rat bone marrow was examined. On the first day after injection, fibrous tissues formed in the treated region of the bone marrow. Tissue-nonspecific alkaline phosphatase (TNAPase)-immunopositive osteoblastic cells and osteopontin immunopositive-extracellular matrices were observed in the fibrous tissues, indicating bone induction. On the fifth day, the bFGF-induced bone was found broadly in the bone marrow. In the originally existing bone, osteopontin-immunoreactivity was observed at cement lines, but not in the fully calcified matrix, whereas the woven bone displayed immunoreactivity throughout the matrix. Numerous TRAPase-positive osteoclasts were present on the surfaces of the woven bone, but no obvious cement line was observed. Therefore, both bone formation and resorption appeared highly active, without normal cellular coupling equilibrated between bone formation and resorption performed by osteoblasts and osteoclasts. On the tenth day, the bFGF-induced bone was almost replaced by bone marrow. Thus, bone formation actively occurred in the first half of the experimental period, whereas bone resorption came to be predominant thereafter. This study demonstrated that bFGF stimulates bone formation, which, however, is subject to subsequent resorption, probably due in part to the absence of coordinated cellular coupling between osteoclasts and osteoblasts.


Asunto(s)
Médula Ósea/fisiología , Resorción Ósea , Factor 2 de Crecimiento de Fibroblastos/farmacología , Osteogénesis , Fosfatasa Ácida/análisis , Fosfatasa Alcalina/análisis , Animales , Médula Ósea/efectos de los fármacos , Médula Ósea/ultraestructura , Inmunohistoquímica , Hibridación in Situ , Masculino , Microscopía Electrónica , Osteoblastos/enzimología , Osteoblastos/ultraestructura , Osteoclastos/enzimología , Osteoclastos/ultraestructura , Osteonectina/genética , Osteopontina , Ratas , Ratas Wistar , Sialoglicoproteínas/análisis , Factores de Tiempo
16.
J Gastroenterol ; 29(3): 349-56, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8061805

RESUMEN

A young woman presented with high fever and edema in January, 1984, and was diagnosed as having systemic lupus erythematosus. Prednisolone administration failed to improve her symptoms. In May she was admitted to hospital because of elevated erythrocyte sedimentation rate (ESR), hypoproteinemia, hypogammaglobulinemia, hypocomplementemia, positive antinuclear antibody, elevated immune complex level, and diarrhea. Edema disappeared following administration of diuretics and albumin, although the pathogenesis was still undetermined. In September, she was referred to our institution because of severe watery diarrhea and hypoproteinemia. Endoscopic examination showed a diffuse inflammatory lesion in the duodenum and the colon. Radioisotopic 51Cr-albumin study results were compatible with protein-losing enteropathy. Hypoproteinemia and inflammatory changes of the intestine were improved by antibiotics, suggesting that the inflammatory lesion was caused by bacterial infection. Despite the improvements in clinical symptoms and laboratory findings, the serum IgA level was still low and the thrombocytopenia remained. The morphological characteristics of the megakaryocytes were consistent with idiopathic thrombocytopenic purpura. In May, 1986, the thrombocytopenia deteriorated, causing purpura. Prednisolone was administered again, and this resulted in normalization of the platelet count, although the IgA level remained low. Finally the prednisolone was stopped, and the IgA level gradually recovered, with the improvement of the enterocolitis. The exact pathogenesis of the whole picture in this case is unclear, but an 8-year-long clinical course suggests that the protein-losing was caused by an infectious enterocolitis superimposed on IgA deficiency.


Asunto(s)
Enterocolitis/complicaciones , Deficiencia de IgA/complicaciones , Inmunoglobulina A/sangre , Enteropatías Perdedoras de Proteínas/etiología , Púrpura Trombocitopénica Idiopática/complicaciones , Adulto , Colon/patología , Enterocolitis/diagnóstico , Femenino , Humanos , Prednisolona/uso terapéutico , Enteropatías Perdedoras de Proteínas/diagnóstico , Enteropatías Perdedoras de Proteínas/patología , Púrpura Trombocitopénica Idiopática/diagnóstico , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico
17.
Chemosphere ; 45(8): 1167-71, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11695630

RESUMEN

Dioxins (PCDD + PCDF) and polychlorinated biphenyl (PCB) are potentially hazardous compounds and have structural similarity to thyroid hormones. Our research group on "Dioxins and PCB in Human Milk" was organized in 1997 and has been active for the past three years. We collected breast milk from 80 mothers living in Tokyo, Saitama, Ishikawa and Osaka Prefecture in Japan at 5, 30, 150, 300 postpartum days and measured PCDDs, PCDFs and PCBs during 1998-1999. We added another 20 prefectures and cities during 1999-2000. Breast milk was obtained from 415 mothers at 30 postpartum days (breast-feeding group). Blood was taken from infants who were breast-fed at the age of 1 year for evaluation of thyroid and immune functions. Blood was also taken from 53 infants who were bottle-fed (bottle-feeding group) as a control. Serum T4, T3, FT4 and TSH levels in the breast-feeding (n = 337) and bottle-feeding (n = 53) groups were within normal ranges and were not significantly different between the two groups. Although there were a large geographic differences of dioxins and co-PCB content in breast milk, there were no differences in serum T4, T3, FT4, TSH levels and no significant correlation between the mean serum levels of TSH and TEQ in breast milk. There was a significant correlation between serum TSH at 1 year of age and that from blood on dried filter paper TSH at 5 days of age. We concluded that dioxin intake from breast milk in Japanese infants did not impair thyroid function. However, long-term effects remain to be evaluated.


Asunto(s)
Dioxinas/efectos adversos , Exposición a Riesgos Ambientales , Contaminantes Ambientales/efectos adversos , Leche Humana/química , Bifenilos Policlorados/efectos adversos , Glándula Tiroides/efectos de los fármacos , Glándula Tiroides/fisiología , Adulto , Lactancia Materna , Femenino , Humanos , Lactante , Japón , Masculino , Pruebas de Función de la Tiroides
18.
Artículo en Inglés | MEDLINE | ID: mdl-11400741

RESUMEN

A screening program for congenital adrenal hyperplasia (CAH) in Sapporo began in 1982, 7 years prior to the introduction of the national program. Since its inception, testing has involved the detection of 17-hydroxyprogesterone (17-OHP) in dried blood samples, using ELISA. Up to the end of March 1998, of 298,731 newborn screened, second samples were requested in 1,723 cases (0.6%). This number included 789 newborns who weighed less than 2,000 gm at birth. A total of 14 cases were diagnosed with 21-hydroxylase deficiency (21-OHD). "Salt-wasting type (SW)" outnumbered "simple virilizing type (SV)" by 11:3. The ratio of male to female was a converse. but unrelated, 3:11. Our study from 1982-1997 revealed that the incidence of 21-OHD in Sapporo City was 1:21.338, markedly similar to the worldwide incidence of 1:15,000. In order to improve the program, other type of analysis are also currently in use and under evaluation. These include highly sensitive HPLC analysis for 17-OHP and molecular analysis to identify some mutations associated with the 21-OHD gene (CYP21). These methodologies are very useful for the confirmation of information acquired from dried blood specimens.


Asunto(s)
Hiperplasia Suprarrenal Congénita/diagnóstico , Tamizaje Neonatal , 17-alfa-Hidroxiprogesterona/sangre , Hiperplasia Suprarrenal Congénita/epidemiología , Cromatografía Líquida de Alta Presión , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Incidencia , Recién Nacido , Japón/epidemiología , Masculino
19.
Artículo en Inglés | MEDLINE | ID: mdl-15906689

RESUMEN

Japan was the first country to establish a nationwide quality control system. When the Japanese Federal Government initiated Nationwide Neonatal Screening in 1977, the system officially included a Quality Control (QC) System that should cover all screening laboratories in Japan. This QC system is quite different from that for usual clinical chemistry. The aim of the National QC System for Neonatal Screening is evaluation of the accuracy of the tests and evaluation of the ability to detect suspicious samples with very mild abnormalities. For accomplishing the aim, the QC center established an inter-laboratory QC survey Screening laboratories having weak points can be identified through the inter-laboratory QC survey, and the Center must find a way to improve the ability of these screening laboratories. This requires a nationwide consensus regarding the cut-off levels of tested materials. Based on the cooperation of the Societies For Mass-screening, of Inborn Errors of Metabolism and of Pediatric Endocrinology, we set low cutoff levels for each compound to minimize the number of false negative cases. The system also included the evaluation of the quality of essential screening reagents and the special filter paper for blood collection (in partnership with the production companies). For this purpose, we developed some new methods for evaluating the standard-compounds for the various screening tests exactly, except in the case of TSH screening.


Asunto(s)
Laboratorios/normas , Errores Innatos del Metabolismo/diagnóstico , Programas Nacionales de Salud/normas , Tamizaje Neonatal/normas , Control de Calidad , Gestión de la Calidad Total , Humanos , Recién Nacido , Japón
20.
Artículo en Inglés | MEDLINE | ID: mdl-11400777

RESUMEN

We report the outline and results of our experience with a group training course of neonatal screening for health care professionals in developing countries. Sapporo City Institute of Public Health (SCIPH) has been offered a training course on neonatal screening once a year since 1991 under the Technical Training Program of the Japan International Cooperation Agency (JICA). The aims of this training course are to enhance the participants' technical knowledge and skills, and also to deepen their understanding of the principle of neonatal screening as well as the relevant diseases. Lectures and laboratory practice on phenylketonuria (PKU), congenital hypothyroidism (CH), congenital adrenal hyperplasia (CAH) and neuroblastoma are included in the 3-month program. After the completion of the training, participants are expected to play a major role in establishing and expanding neonatal screening system in each of their countries. We have received a total of 67 participants from 25 countries until March 1998: 58 pediatricians; 2 gynecologists; 6 biochemists; 1 administrative officer. After they returned to their countries, 11 engaged in neonatal screening and started PKU and CH screening in their institute, city or province in Argentina, Brazil, Mexico, Peru and Thailand. We believe that these results fulfilled our objectives. Also, for follow-up, SCIPH has been giving information and consultation to the participants on requests. This international cooperation network could also benefit our present network of the International Society Screening in the future.


Asunto(s)
Países en Desarrollo , Educación Médica Continua , Cooperación Internacional , Tamizaje Neonatal , Humanos , Recién Nacido , Japón
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