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1.
Helminthologia ; 60(3): 263-271, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38152472

RESUMEN

In April 2019, baobab (Adansonia digitata L.) seedlings from Thailand, exhibiting galls on the roots, were intercepted during an import plant quarantine inspection at Chubu Centrair International Airport, Japan. Root-knot nematodes (RKNs) were extracted from the galled roots of baobab seedlings and identified by morphological, morphometrical and molecular methods as the guava root-knot nematode, Meloidogyne enterolobii Yang & Eisenback. The morphology and morphometrics of the intercepted population were similar to those of the original and subsequent descriptions of M. enterolobii. The sequences of D2-D3 of 28S rRNA, mtDNA intergenic COII-16S rRNA and COI genes obtained in this study matched well (99-100% similarity) with each of the gene sequences of M. enterolobii deposited in GenBank. Phylogenetic analysis of these genes revealed that the intercepted population clustered with M. enterolobii and clearly differed from other RKN species. To the best of our knowledge, this is the first report of M. enterolobii from baobab.

2.
Radiat Prot Dosimetry ; 161(1-4): 139-43, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24368868

RESUMEN

Neutron activation cross sections for Bi and Co at 386 MeV were measured by activation method. A quasi-monoenergetic neutron beam was produced using the (7)Li(p,n) reaction. The energy spectrum of these neutrons has a high-energy peak (386 MeV) and a low-energy tail. Two neutron beams, 0° and 25° from the proton beam axis, were used for sample irradiation, enabling a correction for the contribution of the low-energy neutrons. The neutron-induced activation cross sections were estimated by subtracting the reaction rates of irradiated samples for 25° irradiation from those of 0° irradiation. The measured cross sections were compared with the findings of other studies, evaluated in relation to nuclear data files and the calculated data by Particle and Heavy Ion Transport code System code.


Asunto(s)
Bismuto/química , Cobalto/química , Neutrones , Aceleradores de Partículas , Radiometría/instrumentación , Radiometría/métodos , Iones Pesados , Protones , Dosis de Radiación , Radioisótopos/química , Reproducibilidad de los Resultados
3.
Opt Express ; 21(2): 2171-84, 2013 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-23389198

RESUMEN

In order to determine if the mesa geometry might affect the properties of the coherent terahertz (THz) radiation emitted from the intrinsic Josephson junctions in mesas constructed from single crystals of the high-temperature superconductor, Bi2Sr2CaCu2O8+δ, we studied triangular mesas. For equilateral triangular mesas, the observed emission was found to be limited to the single mesa TM(1,0) mode. However, tunable radiation over the range from 0.495 to 0.934 THz was found to arise from an acute isosceles triangular mesa. This 47% tunability is the widest yet observed from the outer current-voltage characteristic branch of such mesas of any geometry. Although the radiation at a few of the frequencies in the tunable range appear to have been enhanced by cavity resonances, most frequencies are far from such resonance frequencies, and can only be attributed to the ac-Josephson effect.


Asunto(s)
Cerámica/química , Iluminación/instrumentación , Semiconductores , Radiación Terahertz , Cerámica/efectos de la radiación , Diseño de Equipo , Análisis de Falla de Equipo
4.
Science ; 333(6046): 1119-21, 2011 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-21868669

RESUMEN

A single grain (~3 micrograms) returned by the Hayabusa spacecraft was analyzed by neutron activation analysis. This grain is mainly composed of olivine with minor amounts of plagioclase, troilite, and metal. Our results establish that the Itokawa sample has similar chemical characteristics (iron/scandium and nickel/cobalt ratios) to chondrites, confirming that this grain is extraterrestrial in origin and has primitive chemical compositions. Estimated iridium/nickel and iridium/cobalt ratios for metal in the Itokawa samples are about five times lower than CI carbonaceous chondrite values. A similar depletion of iridium was observed in chondrule metals of ordinary chondrites. These metals must have condensed from the nebular where refractory siderophile elements already condensed and were segregated.

5.
Fukushima J Med Sci ; 44(2): 59-67, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10091378

RESUMEN

To explore the change in age distribution of patients with uterine cervical cancer and its precursors, we analyzed 2,168,923 women in a series of mass screening for uterine cervical cancer in Fukushima Prefecture. The first examination rate was not increased over a 20-year period. During the screening period, severe dysplasia was found in 693 women, carcinoma in situ in 672 women, microinvasive carcinoma in 517 women, and frank invasive carcinoma in 421 women. The numbers of patients with frank invasive carcinoma was decreased gradually in every age group, which might reflect the effectiveness of our mass screening project. Although the detection rates of severe dysplasia, carcinoma in situ and microinvasive carcinoma have not changed in patients groups over 40 years old, the detection rates were increased in patients under the age of 39. These results may reflect a recent tendency for cervical cancer to increase in young women. It is important, therefore, to increase the screening rate for young women to prevent the progression with advanced cervical cancer.


Asunto(s)
Neoplasias del Cuello Uterino/epidemiología , Adulto , Distribución por Edad , Anciano , Femenino , Humanos , Japón/epidemiología , Tamizaje Masivo , Persona de Mediana Edad , Displasia del Cuello del Útero/epidemiología
6.
Neuroreport ; 6(5): 797-800, 1995 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-7605951

RESUMEN

Several EEG studies have reported an early component of the visual evoked potential. However, it is controversial whether this component is cortical or subcortical. Our study has aimed to clarify this problem using MEG and EEG in nine normal volunteers. A total of 4000 stimuli were presented to the monocular visual hemifield through a light-proof stimulating goggle and the visual evoked magnetic field and visual evoked potential was measured above the occipital lobe. The early component was observed in three of the nine subjects. The latency ranged from 40 to 45 ms in MEG and from 39 to 47 ms in EEG. The result of dipole localization analysis showed that its origin was cortical, and specifically, the striate cortex.


Asunto(s)
Electroencefalografía , Campos Electromagnéticos , Potenciales Evocados Visuales/fisiología , Magnetoencefalografía , Adulto , Femenino , Humanos , Masculino , Tiempo de Reacción/fisiología , Valores de Referencia
7.
J Neurochem ; 64(1): 354-63, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7798932

RESUMEN

Changes in tubulin solubility during neurite formation were studied biochemically using rat dorsal root ganglion neurons in culture. When fractionated with Ca(2+)-containing buffer at low temperature, a considerable proportion of total cellular tubulin was recovered in the insoluble fraction. We designated this cold/Ca(2+)-insoluble tubulin (InsT) and distinguished it from cold/Ca(2+)-soluble tubulin (SoIT). From the relative amount of InsT, neurite formation was found to proceed through two distinct stages. The first 6 days after plating (stage 1) in which the proportion of InsT increased dramatically (from 5 to 60%) coincided with neurite outgrowth. In the following period (stage 2), a constant level of InsT was maintained, whereas neurite maturation took place. Pulse-labeling experiments further revealed that the two stages differed significantly in terms of tubulin metabolism. High rates of synthesis as well as conversion from SoIT to InsT were observed in stage 1, whereas stage 2 was characterized by a decrease in both of these rates and an increase in the rate of degradation. The results show for the first time the coordinated changes in tubulin metabolism that underlie the process of neurite formation.


Asunto(s)
Neuritas/metabolismo , Neuritas/ultraestructura , Tubulina (Proteína)/metabolismo , Animales , Diferenciación Celular/fisiología , Células Cultivadas , Ganglios Espinales/citología , Immunoblotting , Microtúbulos/química , Microtúbulos/metabolismo , Neuritas/química , Ratas , Ratas Wistar , Radioisótopos de Azufre , Tubulina (Proteína)/análisis
8.
Neurosci Res ; 19(3): 295-302, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-7520144

RESUMEN

Actin is one of the major cytoskeletal proteins carried in slow axonal transport. Since more than 50% of actin in the axon was recovered in the high-speed supernatant, we looked for G-actin-binding proteins in slow axonal transport. Two weeks after injection of L-[35S]methionine into the rat spinal cord (L3-L5), labeled proteins in the sciatic nerve were extracted and those with potential abilities to interact with G-actin were detected by two independent methods: (A) DNAase I affinity chromatography and (B) blot overlay with biotinylated actin. By method (A), a 68 kDa Ca(2+)-dependent binding protein and a 45 kDa Ca(2+)-independent binding protein were detected. The 68 kDa protein was also a major protein binding to actin in method (B). The 68 kDa protein was identified with the Ca(2+)-dependent phospholipid binding protein annexin VI by two-dimensional electrophoresis and Western blotting. As annexin VI is a component of slow axonal transport, it does not seem to be bound to membranous organelles in the axon. Our results suggest that annexin VI may play a role in the control of actin assembly and membrane-microfilament interaction.


Asunto(s)
Actinas/metabolismo , Proteínas de Microfilamentos/metabolismo , Nervio Ciático/fisiología , Animales , Transporte Axonal , Calcio/farmacología , Cromatografía de Afinidad , Desoxirribonucleasa I , Electroforesis en Gel Bidimensional , Electroforesis en Gel de Poliacrilamida , Immunoblotting , Masculino , Metionina/metabolismo , Proteínas de Microfilamentos/biosíntesis , Proteínas de Microfilamentos/aislamiento & purificación , Peso Molecular , Ratas , Ratas Wistar , Médula Espinal/fisiología , Radioisótopos de Azufre
9.
Tohoku J Exp Med ; 170(3): 135-46, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8259587

RESUMEN

In order to determine the would healing process in the portio vaginalis uteri, 3[H]-thymidine incorporation and hydroxyproline concentration in the granulation tissue were measured histochemically after CO2-laser treatment. As a result, the squamous epithelium showed the thymidine uptake in extended regions in the first week and in basel cell hyperplastic regions in the second week. The uptake was seen in the reserve cell hyperplastic regions of the epithelium from the 2nd week. Hydroxyproline concentration peaks mostly appeared within one week after the laser treatment. After cryosurgery, the peaks mostly appeared after two weeks or more. These results indicated that, the stromas and then the squamous and columnar epithelial cells in turn were regenerated after CO2-laser treatment, and that the regeneration occurred earlier after laser treatment than after cryosurgery.


Asunto(s)
Terapia por Láser , Neoplasias del Cuello Uterino/cirugía , Cicatrización de Heridas , Cuello del Útero/patología , Cuello del Útero/fisiopatología , ADN/biosíntesis , Epitelio/patología , Epitelio/fisiología , Femenino , Humanos , Hidroxiprolina/metabolismo , Hiperplasia , Necrosis , Regeneración , Timidina/metabolismo
10.
J Neurochem ; 56(5): 1774-82, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-1826522

RESUMEN

The major 68-kDa protein found selectively in the faster of the two subcomponents of slow axonal transport [group IV or slow component b (SCb)] in the rat sciatic nerve has been characterized. It was found to contain two distinct classes of proteins, S1 and S2, both of which have isoelectric points of 5.7, but differ in their solubility in the presence of calcium. The S1 protein, which contributes up to 70% of the 68-kDa component, was soluble in the presence or absence of calcium, whereas the S2 protein was bound to the cytoskeleton in a calcium-dependent manner. Further characterization of the two proteins by peptide mapping and immunological methods revealed that the S1 protein belonged to a family of proteins related to the 70-kDa heat shock protein, whereas the S2 protein was identical to 68-kDa calelectrin (annexin VI). Selective occurrence in SCb of these proteins with potential abilities to regulate protein-protein or protein-membrane interactions suggests that they may play important roles in the control of cytoskeletal organization in the axon, because SCb contains mainly cytoskeletal proteins in a more dynamic form compared with the slowest rate component, slow component a, which is enriched in the stably polymerized form of these proteins.


Asunto(s)
Axones/metabolismo , Proteínas de Unión al Calcio/metabolismo , Proteínas de Choque Térmico/química , Proteínas del Tejido Nervioso/metabolismo , Animales , Anexinas , Transporte Biológico , Proteínas de Unión al Calcio/química , Masculino , Peso Molecular , Ratas , Ratas Endogámicas
11.
J Electron Microsc Tech ; 12(3): 281-95, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2795234

RESUMEN

The structure of amorphous Se films, in the topological random system, has been studied by the computer-simulation, electron diffraction (ED), and high-resolution transmission electron microscopy (HRTEM). As an example of HRTEM of the cellular random system, our recent investigation on Ba-ferrites is reviewed beforehand. In HRTEM images of spin-glass BaTi2-xSnxFe4O11 (x less than 0.6), magnetic clusters or clusters of FeO6-octahedra surrounded by TiO6-octahedra have been found. The structure of BaSn2Fe4O11 (x = 2) has been determined. The ordering of Sn (Ti) and Fe ions increases with increasing x, which interprets the change from the spin-glass state to nonspin-glass state at x = 0.6. It is shown that a cluster of polarized lattice ions is detectable in images of polar-glass BaxK2-xFexTi6-xO13 (x greater than or equal to 1.2). The structure models of amorphous Se films forming on a substrate have been constructed on a computer, and their radial distribution function (RDF) and HRTEM images have been calculated. Experimental RDF and HRTEM images have been obtained from vacuum-deposited amorphous Se films and are compared with the calculated ones. It is concluded that in the as-deposited films most of Se molecules may be composed of Se atoms as small as three and that by the electron-beam irradiation the molecules link to form spiral chains in amorphous state and then arrange to have the hexagonal crystal structure.


Asunto(s)
Selenio/análisis , Fenómenos Químicos , Química , Simulación por Computador , Cristalización , Microscopía Electrónica/métodos , Estructura Molecular , Difracción de Rayos X
14.
Gan No Rinsho ; 31(6 Suppl): 679-84, 1985 May.
Artículo en Japonés | MEDLINE | ID: mdl-4032753

RESUMEN

CO2 evaporation was undertaken on 241 patients with cervical intraepithelial neoplasia. The results obtained six weeks after the treatment revealed disappearance of 89.6% of the lesions, and the therapeutic results obtained one year after reirradiation were favorable; 97.5% of the lesions had disappeared. However, not a few patients have some neoplasms of the uterine cervix to which this therapy is not applicable. Therefore, conization was started for treatment combined with diagnosis by means of CO2 laser. The therapeutic effect has been studied in 64 patients to date. Five patients with carcinoma of stage Ia and four patients with endoepithelial carcinoma who had undergone hysterectomy after conization were examined for the presence or absence of residual lesions. The lesions had disappeared completely. The remaining 64 patients who had not undergone hysterectomy are now under follow-up study, and a residual lesion was observed in only one patient, suggesting the possibility of treating a large number of CIN patients by evaporation combined with conization.


Asunto(s)
Carcinoma de Células Escamosas/cirugía , Terapia por Láser , Neoplasias del Cuello Uterino/cirugía , Adulto , Carcinoma de Células Escamosas/patología , Femenino , Humanos , Persona de Mediana Edad , Neoplasias del Cuello Uterino/patología , Volatilización
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