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1.
Biochim Biophys Acta ; 955(2): 128-34, 1988 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-3395618

RESUMEN

The small-angle X-ray scattering was observed from beta-casein micelles in 0.2 M phosphate buffer (pH 6.7) with varying temperatures. An oblate ellipsoid of a rigid core with a thin soft layer was proposed as a probable model of the beta-casein micellar structure, according to the results of the model optimization with simple triaxial bodies. Here the axial ratio was found to decrease and the micelle to become spherical when the polymerization proceeds with temperature. The consistency of the present model was examined with the results of hydrodynamic measurements published previously.


Asunto(s)
Caseínas , Coloides , Micelas , Algoritmos , Dispersión de Radiación , Rayos X
2.
Biomaterials ; 11(6): 430-4, 1990 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2207234

RESUMEN

A water-insoluble silk fibroin membrane was prepared by immersing a silk fibroin membrane as cast in 50 vol% aqueous methanol solution for different periods of time at 25 degrees C. To use the membrane as a biomaterial, oxygen and water vapour permeability, transparency, mechanical property and enzymatic degradation behaviour in vitro of the membrane in the wet state were investigated. These physico-chemical properties changed according to the condition of the methanol treatment. The membrane had oxygen permeability, water vapour permeability, transparency and biodegradability.


Asunto(s)
Materiales Biocompatibles , Fibroínas , Proteínas de Insectos , Proteínas , Textiles , Biodegradación Ambiental , Ensayo de Materiales , Oxígeno/química , Permeabilidad , Seda , Resistencia a la Tracción , Agua/química
3.
Eur J Pharmacol ; 366(1): 47-53, 1999 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-10064151

RESUMEN

We evaluated the ability of various drugs to prevent the decrease in focal cochlear blood flow induced by photochemical reaction and investigated the mechanisms underlying this decrease. By means of a photochemical reaction, which produces reactive oxygen species, focal lesions measuring about 1 mm in diameter were induced in the lateral wall of the guinea pig cochlea. The protective effects of hydrocortisone, amidotrizoate and ATP on cochlear blood flow and cochlear vascular conductance changes were evaluated by using a non-contact laser flowmeter. Cochlear blood flow and cochlear vascular conductance were decreased to 65.1+/-4.9% (mean +/- S.E.M.) and 57.0+/-3.7% (mean +/- S.E.M.) of the initial level 30 min after the start of the photochemical reaction, respectively. Hydrocortisone significantly prevented the decline in the cochlear blood flow and cochlear vascular conductance and reduced the area of stria vascularis degeneration in a dose-dependent manner. Neither amidotrizoate nor ATP significantly prevented the decrease in cochlear blood flow or cochlear vascular conductance. Hydrocortisone was more effective than vasodilators or other agents which increase cochlear blood flow in preventing the photochemically induced decrease in cochlear blood flow. This might be due to the antioxidative effects of hydrocortisone.


Asunto(s)
Adenosina Trifosfato/farmacología , Corticoesteroides/farmacología , Cóclea/efectos de los fármacos , Medios de Contraste/farmacología , Microcirculación/efectos de los fármacos , Animales , Presión Sanguínea/efectos de los fármacos , Cóclea/irrigación sanguínea , Cóclea/patología , Diatrizoato/farmacología , Cobayas , Hidrocortisona/farmacología , Flujometría por Láser-Doppler , Microcirculación/patología , Microscopía Electrónica de Rastreo , Fotoquímica , Flujo Sanguíneo Regional/efectos de los fármacos , Estría Vascular/efectos de los fármacos , Estría Vascular/patología , Estría Vascular/ultraestructura , Resistencia Vascular/efectos de los fármacos
4.
Hear Res ; 128(1-2): 103-11, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10082290

RESUMEN

To estimate the correlation between the cochlear lateral wall and endocochlear potential (EP), the EP was measured at different time intervals up to 3 weeks at cochlear focal lesions made in the guinea pig. Lesions were produced by a photochemical reaction between systemically administered Rose Bengal and green light illumination in the second cochlear turn. Focal strial lesions (mean diameter 975 microm) became apparent under a scanning electron microscope 60 min after illumination, and degeneration of the organ of Corti was recognized at 3 days. The EP was measured continuously for 1 h following onset of the reaction in eight ears. In the other ears, EP measurements were done after various intervals of time up to 3 weeks. The EP showed two declines from pre-illumination level. The first started soon after illumination, reached a minimum value at 25 min, and then slightly recovered by 1 h. The second decline appeared at 3 days after illumination. In contrast to evident focal morphological degeneration 2 weeks post illumination, the EP values had recovered to almost normal. We suggest that the sequential changes in the EP were produced depending on the degeneration and then repairing processes of the endolymphatic boundary tissues.


Asunto(s)
Cóclea/fisiopatología , Enfermedades Cocleares/fisiopatología , Animales , Cóclea/efectos de los fármacos , Cóclea/patología , Cóclea/efectos de la radiación , Enfermedades Cocleares/inducido químicamente , Enfermedades Cocleares/etiología , Enfermedades Cocleares/patología , Color , Electrofisiología , Cobayas , Hipoxia/fisiopatología , Luz , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Rosa Bengala/farmacología , Factores de Tiempo
5.
Hear Res ; 153(1-2): 7-13, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11223292

RESUMEN

This study was designed to evaluate the role of endogenous nitric oxide (NO) in focal microcirculation disorder of the guinea pig cochlea. Focal microcirculation disorder was induced by a photochemical reaction at the lateral wall of the second cochlear turn. Saline or N omega-nitro-L-arginine methyl ester (L-NAME) was administered before the onset of photochemical reaction. Cochlear blood flow (CBF) was measured at the focal lesion (ischemic core), 1 mm from the lesion in the apical and basal direction (ischemic border zone) by using a novel non-contact laser blood flowmeter. NO synthase activities were measured by radioenzymeassay. In the saline pretreatment group, CBF was significantly decreased to 58.8+/-4.4% of the baseline at the ischemic core 30 min after the onset of photochemical reaction (P<0.01), while CBF showed no significant change at the ischemic border zone. In the L-NAME pretreatment group, CBF was significantly decreased not only at the focal lesion (48.3+/-6.5%, P<0.01), but also at the ischemic border zone (apical, 49.3+/-2.3%, P<0.05; basal, 58.7+/-7.1%, P<0.05, respectively). NO synthase III activity of cochlea was increased significantly (P<0.01) 15 min after microcirculation disorder. These findings suggest that formation of endogenous NO plays a key role in the maintenance of CBF in acute focal cochlear microcirculation disorder.


Asunto(s)
Cóclea/irrigación sanguínea , Cóclea/fisiopatología , Óxido Nítrico/fisiología , Animales , Enfermedades Cocleares/etiología , Enfermedades Cocleares/fisiopatología , Inhibidores Enzimáticos/farmacología , Cobayas , Microcirculación/fisiopatología , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico Sintasa/antagonistas & inhibidores , Fotoquímica , Especies Reactivas de Oxígeno/metabolismo , Flujo Sanguíneo Regional , Enfermedades Vasculares/etiología , Enfermedades Vasculares/fisiopatología
6.
Hear Res ; 129(1-2): 83-91, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10190754

RESUMEN

Megalin is an endocytic receptor predominantly expressed in the kidney proximal tubule cells. In the present study, localization of megalin was examined using a post-embedding immunogold method in the rat cochlear duct. Marginal cells of the stria vascularis were labeled on the apical surface, but not on the basolateral surface. This localization pattern resembles kidney proximal tubule cells. Immunoreactivity was also detected on various other cells, including epithelial cells of the spiral prominence and epithelial cells of Reissner's membrane. In contrast, virtually no gold particles were seen on intermediate cells and basal cells of the stria vascularis, mesothelial cells of Reissner's membrane or fibrocytes in the lateral wall. Also unlabeled were cells in the tympanic wall of the cochlear duct, including sensory cells and supporting cells of the organ of Corti. The present findings show the involvement of megalin in endocytosis of marginal cells and are suggestive of different uptake mechanisms for aminoglycosides in the kidney proximal tubule cells and in the cochlear sensory cells.


Asunto(s)
Conducto Coclear/metabolismo , Conducto Coclear/ultraestructura , Glicoproteínas de Membrana/metabolismo , Animales , Oído Medio/metabolismo , Oído Medio/ultraestructura , Complejo Antigénico de Nefritis de Heymann , Túbulos Renales Proximales/metabolismo , Microscopía Inmunoelectrónica , Ratas , Ratas Wistar , Distribución Tisular
7.
Brain Dev ; 23(5): 321-6, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11504604

RESUMEN

Spinal muscular atrophy is an autosomal recessive neurodegenerative disorder with progressive weakness and atrophy of voluntary muscles. The survival motor neuron gene (SMN) is present in two highly homologous copies (SMN1 and SMN2) on chromosome 5q13. Homozygous deletion of exons 7 and 8 of SMN1 is responsible for spinal muscular atrophy. In spinal muscular atrophy patients, SMN2 partially compensates for the lack of SMN1. Previously, we reported the relatively high incidence of a large deletion including the SMN1 region in Japanese spinal muscular atrophy type I patients. In order to further establish the genetic background of Japanese spinal muscular atrophy type I patients, we investigated the SMN1/SMN2 ratio in the carriers. In normal individuals, there is one copy of each gene on the chromosome (the SMN1/SMN2 ratio was 1). Among 15 carriers (14 parents and one carrier sibling of Japanese type I spinal muscular atrophy patients with homozygous deletion of exons 7 and 8 of SMN1), we found that the SMN1/SMN2 ratio was 0.5 or 1 in 11 (73.3%) carriers. The remaining four carriers had an SMN1/SMN2 ratio of 1/3. This finding supports the idea that deletion rather than conversion is the main genetic event in type I spinal muscular atrophy. In addition, the ratio of SMN1/SMN2 among Japanese carriers, which was thought to be higher than that of the Western population, was compatible with the results obtained in Western populations. For further insight into the characteristic genetic background of spinal muscular atrophy in Japanese, determination of the gene copy number is essential.


Asunto(s)
Cromosomas Humanos Par 5/genética , Eliminación de Gen , Dosificación de Gen , Mutación/genética , Proteínas del Tejido Nervioso/genética , Atrofias Musculares Espinales de la Infancia/genética , Proteína de Unión a Elemento de Respuesta al AMP Cíclico , Análisis Mutacional de ADN , Exones/genética , Femenino , Genotipo , Humanos , Japón , Masculino , Repeticiones de Microsatélite/genética , Proteínas de Unión al ARN , Proteínas del Complejo SMN , Proteína 1 para la Supervivencia de la Neurona Motora , Proteína 2 para la Supervivencia de la Neurona Motora
8.
IEEE Trans Pattern Anal Mach Intell ; 5(4): 433-41, 1983 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21869128

RESUMEN

This paper describes a facsimile-based graphics editing system using handwritten mark recognition, and presents some experimental results with the system. In a manner different from usual graphics editors based on CRT displays and data tablets, only facsimiles are used as input and output devices in this system. As the first stage in processing, a graphic subject is first given as a set of line drawings and characters handwritten on a sheet of paper, and it is then input into the computer as a binary picture from a facsimile transmitter. Auxiliary editing information is input into the computer as handwritten marks or seal marks prepared on a separate sheet of paper. As the second stage, the marks are recognized and used to create a mark parameter list for the graphics editing. Third, referencing the mark parameter list, the graphics are expressed by using a set of graphic commands, and edited by the computer. Finally, a correct edited copy of the graphics is constructed by picture processing based on graphic commands, and it is output to a facsimile receiver. Very good results have been obtained for various kinds of hand-written graphics by using the system described here.

9.
Int J Biol Macromol ; 13(5): 286-8, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1801902

RESUMEN

Investigations are reported on the possibility of the direct transformations from alpha-helices to beta-sheets in poly(D-alanine) by heating and the immersion into formic acid, and were concluded that intrahelical hydrogen bonds in the alpha-helix were stable, while interhelical interactions in the alpha-helix crystal were weakened, and beta-sheets did not transform directly from alpha-helices, but grew from random coils.


Asunto(s)
Péptidos/química , Rastreo Diferencial de Calorimetría , Conformación Molecular , Espectrofotometría Infrarroja , Difracción de Rayos X
10.
Acta Otolaryngol ; 118(5): 666-72, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9840502

RESUMEN

The focal microcirculation damage induced by a photochemical reaction in the stria vascularis (SV) of the guinea pig cochlea was evaluated using a non-contact laser blood flowmeter (NCLBF) and the endocochlear potential (EP). Focal degeneration, including vascular thrombosis in the SV produced by the systemic infusion of rose bengal, and the illumination of green light in the second cochlear turn were observed with scanning and transmission electron microscopy. The NCLBF probe was placed at a position 10 mm from the cochlear surface, and the diameter of the laser light was focused to 1 mm in the green light illumination area. The change in NCLBF values induced by the loading of anoxia and administration of epinephrine agreed very well with those obtained with a conventional contact-type laser Doppler flowmeter. Significant decreases in the cochlear blood flow (CBF) (p < 0.01) and EP (p < 0.01) were observed at the site of the photochemical injury compared with the values at the non-illuminated area. CBF gradually decreased (82.0+/-7.3% at 10 min, 71.2+/-5.5% at 20 min, 64.3+/-11.2% at 30 min from the baseline, n=7), but blood pressure was stable. The EP values also decreased gradually during the first 13 min (79.9+/-3.7 mV at pre-illumination, 11.4+/-10.7 mV at 13 min, n=7). The gradual decline in the EP was comparable to the changes in the CBF. The NCLBF was useful for evaluating the haemodynamic properties of the cochlear microcirculation disorders, and this animal model is expected to be suitable for studying the pathology of focal cochlear vascular disease.


Asunto(s)
Cóclea/irrigación sanguínea , Flujometría por Láser-Doppler/métodos , Animales , Cóclea/efectos de la radiación , Potenciales Microfónicos de la Cóclea/fisiología , Femenino , Cobayas , Hemodinámica , Flujometría por Láser-Doppler/instrumentación , Flujometría por Láser-Doppler/estadística & datos numéricos , Microcirculación/fisiología , Microcirculación/efectos de la radiación , Fotoquímica , Estría Vascular/fisiología , Estría Vascular/efectos de la radiación , Factores de Tiempo
11.
No To Shinkei ; 47(11): 1092-7, 1995 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-7495616

RESUMEN

A 68-year-old man was admitted with suprasellar cystic tumor with obstructive hydrocephalus, and complaining of slowly progressive memory disturbance, gait disturbance and urinary incontinence. Neurological examination revealed bilateral visual disturbance and disorientation. Skull X-ray films revealed no dilatation of sella turnica and mild erosion of the dorsum sellae. A cystic suprasellar tumor was revealed extending upward to the third ventricular floor and the solid part of the tumor was homogeneously enhanced with Gd-DTPA on MRI. The T1-weighted sagittal MR image revealed a normal pituitary gland and the diaphragma sellae below the tumor. The tumor was totally removed via a bifrontal basal interhemispheric approach, and the tumor was attached to the pituitary stalk and was not contiguous with the pituitary gland. The histological diagnosis was sinusoidal type of chromophobe and non-functioning adenoma. Postoperative MRI revealed a preserved normal pituitary gland and the stalk. To our knowledge, only 11 cases of suprasellar ectopic pituitary adenoma have been reported. We reviewed their neuroradiological features and discussed the pathogenesis. In particular, cystic and nonfunctioning suprasellar ectopic pituitary adenoma may be difficult to distinguish from craniopharyngioma.


Asunto(s)
Adenoma Cromófobo/diagnóstico , Neoplasias Encefálicas/diagnóstico , Coristoma/diagnóstico , Hipófisis , Neoplasias Hipofisarias/diagnóstico , Adenoma Cromófobo/patología , Anciano , Neoplasias Encefálicas/patología , Coristoma/patología , Quistes/patología , Humanos , Masculino , Neoplasias Hipofisarias/patología , Silla Turca
12.
Seishin Shinkeigaku Zasshi ; 96(5): 375-95, 1994.
Artículo en Japonés | MEDLINE | ID: mdl-8078958

RESUMEN

The diagnostic criteria for BPD such as the DSM-III(-R) and DCR, based on polythetic format for prototypal categories, has not always been able to result in accurate clinical diagnosis of BPD. Reasons posited for this were that DSM-III(-R) criteria consist of symptom items based on descriptive phenomenology, even for Axis II personality diagnosis, and that descriptions of the criteria were vague because of the standardization of vocabulary which aimed at improved inter-rater reliability. With the polythetic "yes/no" format, diagnosis was influenced by the determination of only one item; furthermore, different combinations of items yielding a heterogeneous membership might lead to the same diagnosis. It was, therefore, considered difficult to perform an accurate diagnosis of BPD in clinical practices using the existing general diagnostic criteria, and it was realized that the development of new diagnostic criteria for BPD was necessary. For those reasons, we generated a Clinical BPD Scale (CBS) as diagnostic evaluation scale of BPD with considering advantages for clinical use. This reconstituted some features of BPD which have been reported by many researchers, synthesizing symptomatic elements and personality structural elements. CBS is composed of four clusters, Two of these four clusters are evaluated by four grade anchor points which are provided for the rating of the severity of symptoms, and that are illustrated on the radarchart for comprehensive evaluation of the severity of the disorder. CBS was confirmed to have a high degree of validity, and achieved a satisfactory degree of inter-rater reliability by ANOVA ICC, and it has been found in application of CBS to several cases in the clinical practice that the degree of severity of each symptom could be clarified and differential diagnosis was possible with this diagnostic scale. Furthermore, the outcome of treatment could be confirmed at any time during the clinical follow up. In addition, through the dimensions, it is possible to grasp the severity, and further, through spectrum and hierarchy. We considered diagnostic area of BPD and its position by CBS correlating the other closely related disorders.


Asunto(s)
Trastorno de Personalidad Limítrofe/diagnóstico , Personalidad , Escalas de Valoración Psiquiátrica , Trastorno de Personalidad Limítrofe/psicología , Diagnóstico Diferencial , Humanos , Escalas de Valoración Psiquiátrica/normas
16.
Josanpu Zasshi ; 32(1): 62-3, 1978 Jan.
Artículo en Japonés | MEDLINE | ID: mdl-246053

RESUMEN

PIP: An initial movement to promote the natural birth control method, a contraceptive method, based on estimating the infertile phase of menstrual cycle, has been promoted in Japan since 1977. The Japan Association of Family Life has been reorganized in regard to this movement; and a research group leadered by Dr. N. Ojima has been established. Dr. Josef Rotzer was invited to Japan and gave a lecture. He demonstrated the Rotzer Chart, and used the Ogino Method for double checking the correct ovulation day. More lectures are scheduled to be given to the public. In addition to that, leadership education, textbooks, publications, standardization of terminology, are also major subjects for a nation-wide popularization of this contraceptive method.^ieng


Asunto(s)
Servicios de Planificación Familiar , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Japón , Masculino
17.
J Biomed Mater Res ; 39(3): 486-90, 1998 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-9468060

RESUMEN

Hydrogels were prepared from poly(vinyl alcohol) and chitosan in various blend ratios. The water contents of the hydrogels were in the range of 65 to 75 wt %. The attachment and growth of fibroblast cells (L-929) on the hydrogels were studied with a cell culture method. On the hydrogels with more than 15 wt % chitosan content, the attached cells were able not only to remain viable but also to proliferate. The relative cell attachment after incubation for 30 h increased with increasing chitosan content in the hydrogels. Cell attachment and growth on the hydrogel with 40 wt % chitosan content exceeded those on collagen, a widely-used mammalian cell culture substrate. The morphology of the cells attached onto the hydrogels with a lower chitosan content was spherical, but in hydrogels with more than 15 wt % chitosan content, the number of spindle-shaped cells increased with increasing chitosan content.


Asunto(s)
Materiales Biocompatibles , Quitina/análogos & derivados , Alcohol Polivinílico , Células Cultivadas , Quitosano , Elasticidad , Fibroblastos , Geles , Humanos , Agua/química
18.
J Biomed Mater Res ; 28(4): 459-62, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8006050

RESUMEN

A cationic, high-water-content hydrogel membrane composed of poly(vinyl alcohol) (PVA) and poly(ally-biguanido-co-allylamine) hydrochloride (PAB) with positively charged biguanido groups that resemble arginine residues was developed. The PAB was prepared by reacting poly(allylamine) hydrochloride (PAA) with guanyl-O-methyl isourea. PAB/PVA hydrogel membranes were prepared by repeated freezing and thawing. For comparison, hydrogel membranes composed of PAA and PVA were also prepared. The interaction between these hydrogel membranes and mouse fibroblast (L929) was studied by a cell culture method. The PAB hydrogel blend had a relatively low percentage of initial cell attachment. The cell growth on the PAB hydrogel membranes showed a maximum at 5 mol % PAB content that was as high as commercially available plastic films. However, cells on hydrogel membranes with 50 mol % PAB content and 0 mol % PAB content (only PVA) did not seem to grow; neither did the 5/95 PAA/PVA membranes. Water contact angles of hydrogel membranes did not vary with the PAB content. Morphology of the cell attachment was observed by SEM. On the PAB blend hydrogel surfaces, cells were not spindle-shaped and monolayers, but rather cells aggregated in spherical clusters.


Asunto(s)
Alcohol Polivinílico , Alilamina/análogos & derivados , Animales , Biguanidas , Adhesión Celular , División Celular , Células Cultivadas , Fibroblastos/metabolismo , Hidrogel de Polietilenoglicol-Dimetacrilato , Membranas Artificiales , Ratones , Microscopía Electrónica de Rastreo , Polietilenglicoles , Polímeros
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