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1.
Ann Gen Psychiatry ; 19: 38, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32518579

RESUMEN

BACKGROUND: Previous research studies have assessed the relationship between attention to social information and peripheral (e.g., plasma and salivary) oxytocin (OT) levels in typically developing (TD) children and children with autism spectrum disorder (ASD). A relationship between them was observed in TD children, but not in children with ASD. However, this relationship remains unexamined in other age groups. To clarify whether this lack of association is maintained throughout development in individuals with ASD, we aimed to assess the relationship between salivary OT levels and attention to social information in adolescents and adults with and without ASD. METHODS: We recruited male adolescents and adults with ASD (n = 17) and TD participants (n = 24). Using the all-in-one eye-tracking system Gazefinder, we measured the percentage fixation time allocated to social information. We also measured the salivary OT levels and Autism Spectrum Quotient (AQ) of participants. Subsequently, we confirmed group differences and conducted a correlation analysis to investigate the relationships between these three measures. RESULTS: Salivary OT levels did not show any significant difference between the ASD and TD groups and were negatively correlated with the AQ in the whole-group analysis, but not in within-group analysis. Individuals with ASD had significantly lower percentage fixation times than did TD individuals for eye regions in human faces with/without mouth motion, for upright biological motion, and for people regions in the people and geometry movies. The percentage of fixation for geometric shapes in the people and geometry movies was significantly higher in the ASD than in the TD group. In the TD group, salivary OT levels were positively correlated with percentage fixation times for upright biological motion and people and negatively correlated with inverted biological motion and geometry. However, no significant correlations were found in the ASD group. CONCLUSIONS: Our exploratory results suggest that salivary OT levels in adolescents and adults with ASD are less indicative of attention to social stimuli than they are in TD adolescents and adults. It is suggested that their association is slightly weaker in adolescents and adults with ASD and that this attenuated relationship appears to be maintained throughout development.

2.
Eur J Neurol ; 25(12): 1454-1461, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29998508

RESUMEN

BACKGROUND AND PURPOSE: X-linked Charcot-Marie-Tooth disease type 1 (CMTX1), caused by mutations in gap junction protein beta 1 (GJB1), is characterized by various central nervous system symptoms and gender differences of clinical severity. The aim of this study was to identify the frequency and mutation spectrum of CMTX1 patients in Japan and to demonstrate their phenotypic diversities. METHODS: Using three high-throughput sequencing systems, targeted gene panel sequencing on 1483 unrelated index patients with suspected Charcot-Marie-Tooth (CMT) disease was performed. The peripheral and central nervous system involvements of all patients with GJB1 variants were assessed retrospectively and a detailed gender comparison was conducted with the CMT examination score. RESULTS: Twenty-three novel and 36 described GJB1 variants were identified from 88 pedigrees, in which 34 female and 78 male patients were enrolled. Mean age at onset of the male patients was much younger than the females, 21.56 ± 17.63 years vs. 35.53 ± 23.72 years (P = 0.007). Male patients presented with more severe phenotypes in every examination item, but statistical differences were observed only in motor dysfunctions of the lower extremities and vibration sensation. No significant sensory difference was identified between genders, either clinically or electrophysiologically. Central nervous system dysfunctions were found in 15 patients from 12 pedigrees. Therein, six patients developed stroke-like phenotypes, with dysarthria as the leading symptom. CONCLUSIONS: A relatively lower frequency of CMTX1 (5.9%) was demonstrated and a broad mutation spectrum of GJB1 was described. Detailed clinical differences between genders and various central nervous system symptoms were also illustrated, even in the same pedigree.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth/diagnóstico , Conexinas/genética , Disartria/diagnóstico , Mutación , Fenotipo , Adolescente , Adulto , Edad de Inicio , Enfermedad de Charcot-Marie-Tooth/genética , Niño , Preescolar , Disartria/genética , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Linaje , Estudios Retrospectivos , Factores Sexuales , Adulto Joven , Proteína beta1 de Unión Comunicante
3.
Clin Genet ; 92(3): 274-280, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28244113

RESUMEN

BACKGROUND: Mutations in GDAP1 are responsible for heterogeneous clinical and electrophysiological phenotypes of Charcot-Marie-Tooth disease (CMT), with autosomal dominant or recessive inheritance pattern. The aim of this study is to identify the clinical and mutational spectrum of CMT patients with GDAP1 variants in Japan. MATERIALS AND METHODS: From April 2007 to October 2014, using three state-of-art technologies, we conducted gene panel sequencing in a cohort of 1,030 patients with inherited peripheral neuropathies (IPNs), and 398 mutation-negative cases were further analyzed with whole-exome sequencing. RESULTS: We identified GDAP1 variants from 10 patients clinically diagnosed with CMT. The most frequent recessive variant in our cohort (5/10), c.740C>T (p.A247V), was verified to be associated with a founder event. We also detected three novel likely pathogenic variants: c.928C>T (p.R310W) and c.546delA (p.E183Kfs*23) in Case 2 and c.376G>A (p.E126K) in Case 8. Nerve conduction study or sural nerve biopsy of all 10 patients indicated axonal type peripheral neuropathy. CONCLUSION: We identified GDAP1 variants in approximately 1% of our cohort with IPNs, and established a founder mutation in half of these patients. Our study originally described the mutational spectrum and clinical features of GDAP1-related CMT patients in Japan.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth/diagnóstico , Enfermedad de Charcot-Marie-Tooth/genética , Mutación , Proteínas del Tejido Nervioso/genética , Fenotipo , Adolescente , Adulto , Alelos , Niño , Preescolar , Análisis Mutacional de ADN , Femenino , Efecto Fundador , Estudios de Asociación Genética , Genotipo , Haplotipos , Humanos , Japón , Masculino , Persona de Mediana Edad , Proteínas de la Mielina/genética , Linaje , Reproducibilidad de los Resultados , Secuenciación del Exoma , Adulto Joven
4.
Eur J Neurol ; 24(10): 1274-1282, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28771897

RESUMEN

BACKGROUND AND PURPOSE: The microrchidia family CW-type zinc finger 2 gene (MORC2) was newly identified as a causative gene of Charcot-Marie-Tooth disease (CMT) type 2Z in 2016. We aimed to describe the clinical and mutational spectrum of patients with CMT harboring MORC2 mutations in Japan. METHODS: We analyzed samples from 781 unrelated patients clinically diagnosed with CMT using deoxyribonucleic acid microarray or targeted resequencing by next-generation sequencing, and samples from 434 mutation-negative patients were subjected to whole-exome sequencing. We extracted MORC2 variants from these whole-exome sequencing data and classified them according to American College of Medical Genetics standards and guidelines. RESULTS: We identified MORC2 variants in 13 patients. As the second most common causative gene of CMT type 2 after MFN2, MORC2 variants were detected in 2.7% of patients with CMT type 2. The mean age of onset was 10.3 ± 8.7 years, and the inheritance pattern was mostly sporadic (11/13 patients, 84.6%). The clinical phenotype was typically length-dependent polyneuropathy, and electrophysiological studies revealed sensory-dominant axonal neuropathy. Mental retardation was identified in 4/13 patients (30.8%). p.Arg190Trp, as a mutational hotspot, was observed in eight unrelated families. We also identified two novel probably pathogenic variants, p.Cys345Tyr and p.Ala369Val, and one novel uncertain significance variant, p.Tyr332Cys. CONCLUSIONS: Our study is the largest report of patients harboring MORC2 variants. We revealed a clinical and mutational spectrum of Japanese patients with MORC2 variants. More attention should be paid to cognitive impairment, and the responsible mechanism requires further research for elucidation.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth/genética , Mutación , Factores de Transcripción/genética , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Japón , Masculino , Persona de Mediana Edad , Fenotipo , Adulto Joven
5.
Osteoarthritis Cartilage ; 22(6): 845-51, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24721459

RESUMEN

OBJECTIVE: Excessive mechanical stress is considered a major cause of temporomandibular joint osteoarthritis (TMJ-OA). High magnitude cyclic tensile strain (CTS) up-regulates pro-inflammatory cytokines and matrix metalloproteinases (MMPs) in chondrocytes, while selective cyclooxygenase (COX)-2 inhibition has been shown to be beneficial to cytokine-induced cartilage damage. However, the effect of selective COX-2 inhibitors on mechanically stimulated chondrocytes remains unclear. This study evaluated the effect of celecoxib, a selective COX-2 inhibitor, on extracellular matrix (ECM) metabolism of mandibular condylar chondrocytes under CTS. METHODS: Porcine mandibular chondrocytes were subjected to CTS of 0.5 Hz, 10% elongation with celecoxib for 24 h. The gene expressions of COX-2, MMPs, aggrecanase (ADAMTS), type II collagen and aggrecan were examined by real-time PCR. Also, prostaglandin E2 (PGE2) concentrations were determined using enzyme immunoassay kit. The levels of MMP and transcription factor NF-κB were measured by western blot while MMP activity was determined by casein zymography. RESULTS: The presence of celecoxib normalized the release of PGE2 and diminished the CTS-induced COX-2, MMP-1, MMP-3, MMP-9 and ADAMTS-5 gene expressions while recovered the downregulated type II collagen and aggrecan gene expressions. Concurrently, celecoxib showed inhibition of NF-κB and suppression of MMP production and activity. CONCLUSIONS: Celecoxib exerts protective effects on mandibular condylar chondrocytes under CTS stimulation by diminishing degradation and restoring synthesis of ECM.


Asunto(s)
Condrocitos/efectos de los fármacos , Matriz Extracelular/metabolismo , Cóndilo Mandibular/metabolismo , Metaloproteinasas de la Matriz/metabolismo , Pirazoles/farmacología , Sulfonamidas/farmacología , Animales , Antiinflamatorios no Esteroideos/farmacología , Western Blotting , Celecoxib , Células Cultivadas , Condrocitos/metabolismo , Inhibidores de la Ciclooxigenasa 2/farmacología , Matriz Extracelular/efectos de los fármacos , Cóndilo Mandibular/citología , Metaloproteinasas de la Matriz/efectos de los fármacos , Modelos Animales , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Sensibilidad y Especificidad , Estrés Mecánico , Porcinos , Trastornos de la Articulación Temporomandibular/fisiopatología
6.
Sci Rep ; 12(1): 4062, 2022 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-35260750

RESUMEN

The feasibility of joining laser metal deposited Ti6Al4V sheets using laser beam welding was investigated in this article. The additive manufactured sheets were joined using a 3 kW CW YLS-2000-TR ytterbium laser system. The mechanical properties and microstructure of the welded additive manufactured parts (AM welds) were compared with those of the wrought sheets welded using the same laser process. The welds were characterized and compared in terms of bead geometry, microhardness, tensile strength, fractography, and microstructure. The differences in characteristics are majorly found in the width of the bead and tensile strength. The bead width of AM welds appear wider than the wrought welds, and the wrought welds exhibited higher tensile strength and ductility than the AM welds.


Asunto(s)
Soldadura , Aleaciones , Rayos Láser , Resistencia a la Tracción , Titanio/química
7.
J Periodontal Res ; 43(4): 450-8, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18942192

RESUMEN

BACKGROUND AND OBJECTIVE: We studied the effects of honeybee products on the in vitro formation of calcium phosphate precipitates. MATERIAL AND METHODS: Screening tests of the in vitro formation of calcium phosphate precipitates using 20 types of honey and four types of propolis were carried out using the pH drop method. RESULTS: The inhibitory effect on the rate of amorphous calcium phosphate transformation to hydroxyapatite and on the induction time varied greatly among the 20 types of honey and four types of propolis. We classified them according to their effects on decreasing the rate of amorphous calcium phosphate transformation to hydroxyapatite and/or increasing the induction time. Two of the 20 honeys showed little or no inhibition, either on the rate of amorphous calcium phosphate transformation to hydroxyapatite or on the induction time. Six of the honeys reduced the rate of amorphous calcium phosphate transformation to hydroxyapatite by 12-35% and with a 2.5- to 4.4-fold increase in the induction time. The remaining 12 honeys showed even greater activity. Because four of these 12 honeys had an inhibitory effect on the rate of amorphous calcium phosphate formation, they were excluded as candidates for anticalculus agents. Furthermore, three of the four types of propolis showed an inhibitory effect that was the same as or greater than 1-hydroxyethylidene- 1,1-bisphosphonate. CONCLUSION: These results suggest that eight honeys and three types of propolis may have potential as anticalculus agents in toothpastes and mouthwashes.


Asunto(s)
Abejas , Fosfatos de Calcio/química , Miel , Própolis/química , Animales , Calcio/química , Precipitación Química , Durapatita/química , Ácido Etidrónico/química , Fructosa/química , Glucosa/química , Humanos , Concentración de Iones de Hidrógeno , Maltosa/química , Ensayo de Materiales , Fosfatos/química , Sacarosa/química , Factores de Tiempo
8.
Biochim Biophys Acta ; 880(1): 46-53, 1986 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-3942778

RESUMEN

The extracellular poly(3-hydroxybutyrate) depolymerase purified from Alcaligenes faecalis T1 has two disulfide bonds, one of which appears to be necessary for the full enzyme activity. This depolymerase hydrolyzed not only hydrophobic poly(3-hydroxybutyrate) but also water-soluble trimer and larger oligomers of D-(-)-3-hydroxybutyrate, regardless of their solubilities in water. Kinetic analyses with oligomers of various sizes indicated that the substrate cleaving site of the enzyme consisted of four subsites with individual affinities for monomer units of the substrate. Analyses of the hydrolytic products of oligomers, which had labeled D-(-)-3-hydroxybutyrate at the hydroxy terminus, showed that the enzyme cleaved only the second ester linkage from the hydroxy terminus of the trimer and tetramer, and acted as an endo-type hydrolase toward the pentamer and higher oligomers. The enzyme appeared to have a hydrophobic site which interacted with poly(3-hydroxybutyrate) and determined the affinity of the enzyme toward the hydrophobic substrate.


Asunto(s)
Alcaligenes/enzimología , Hidrolasas de Éster Carboxílico/metabolismo , Compuestos de Organosilicio , Poliésteres , Hidrolasas de Éster Carboxílico/antagonistas & inhibidores , Hidroxibutiratos/metabolismo , Cinética , Polietilenglicoles/farmacología , Polímeros/metabolismo , Silicio/farmacología , Relación Estructura-Actividad , Especificidad por Sustrato , Compuestos de Sulfhidrilo/farmacología , Reactivos de Sulfhidrilo/farmacología
9.
Int J Artif Organs ; 28(6): 600-8, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16015570

RESUMEN

To reduce in-stent restenosis rates we have developed newly designed covered stents, in which a stent strut is buried into a microporous elastomeric cover film to provide a physical barrier against tissue ingrowth and a pharmacological reservoir for drug-eluting. The covered stents were prepared by dip-coating balloon expandable stents mounted on a stainless steel rod in a segmented polyurethane (SPU) solution, and were subsequently subjected to laser-processed microporing (pore diameter, 100 microm; interpore distance, 200 microm). The covered stents, which possessed flat luminal surfaces and micropores that were homogeneously arranged on the whole surface of the covering film, were deployed into the bilateral common carotid arteries of normal New Zealand white rabbits. Angiography after one month of implantation showed all stents were patent with little thrombus formation. The mean thickness of the formed neointimal layers was 292 +/- 177 microm (n=8), which was close to the size in non-covered bare stent (231 +/- 58 microm, n=7), but markedly decreased (about 2/3) from that in the previously developed wrapping-type covered stents (415 +/- 173 microm, P<0.01, n=8).


Asunto(s)
Arteria Carótida Común/diagnóstico por imagen , Materiales Biocompatibles Revestidos , Poliuretanos , Stents , Animales , Sistemas de Liberación de Medicamentos/métodos , Rayos Láser , Porosidad , Diseño de Prótesis , Conejos , Radiografía , Propiedades de Superficie , Túnica Íntima/diagnóstico por imagen
10.
J Dent Res ; 94(2): 337-43, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25503611

RESUMEN

Synovial fluid of the joint decreases friction between the cartilage surfaces and reduces cartilage wear during articulation. Characteristic changes of synovial fluid have been shown in patients with osteoarthritis (OA) in the temporomandibular joint (TMJ). OA is generally considered to be induced by excessive mechanical stress. However, whether the changes in synovial fluid precede the mechanical overloading or vice versa remains unclear. In the present study, our purpose was to examine if the breakdown of joint lubrication affects the frictional properties of mandibular condylar cartilage and leads to subsequent degenerative changes in TMJ. We measured the frictional coefficient in porcine TMJ by a pendulum device after digestion with hyaluronidase (HAase) or trypsin. Gene expressions of interleukin-1ß (IL-1ß), cyclooxygenase-2 (COX-2), matrix metalloproteinases (MMPs), type II collagen, and histology were examined after prolonged cyclic loading by an active pendulum system. The results showed that the frictional coefficient increased significantly after HAase (35%) or trypsin (74%) treatment. Gene expression of IL-1ß, COX-2, and MMPs-1, -3, and -9 increased significantly in enzyme-treated TMJs after cyclic loading. The increase in the trypsin-treated group was greater than that in the HAase-treated group. Type II collagen expression was reduced in both enzyme-treated groups. Histology revealed surface fibrillation and increased MMP-1 in the trypsin-treated group, as well as increased IL-1ß in both enzyme-treated groups after cyclic loading. The findings demonstrated that the compromised lubrication in TMJ is associated with altered frictional properties and surface wear of condylar cartilage, accompanied by release of pro-inflammatory and matrix degradation mediators under mechanical loading.


Asunto(s)
Hialuronoglucosaminidasa/farmacología , Articulación Temporomandibular/efectos de los fármacos , Tripsina/farmacología , Animales , Fenómenos Biomecánicos , Cartílago Articular/efectos de los fármacos , Cartílago Articular/patología , Colágeno Tipo II/análisis , Colágeno Tipo II/ultraestructura , Ciclooxigenasa 2/análisis , Fricción , Interleucina-1beta/análisis , Lubrificación , Cóndilo Mandibular/efectos de los fármacos , Cóndilo Mandibular/patología , Metaloproteinasa 1 de la Matriz/análisis , Metaloproteinasa 3 de la Matriz/análisis , Metaloproteinasa 9 de la Matriz/análisis , Osteoartritis/patología , Estrés Mecánico , Porcinos , Líquido Sinovial/fisiología , Articulación Temporomandibular/patología , Articulación Temporomandibular/fisiopatología , Trastornos de la Articulación Temporomandibular/patología
11.
EXS ; 87: 265-77, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10906966

RESUMEN

Dramatic effects of chitin and chitosan on wound healing were demonstrated in field cases of many small animals (dogs and cats), food animals (338 cows) and 142 zoo animals. In comparison with conventional therapy with irrigation and antibiotic administration to wound, new treatment with chitin and chitosan permitted a substantial decrease in treatment frequency with minimum scar formation.


Asunto(s)
Materiales Biocompatibles , Quitina/análogos & derivados , Quitina/uso terapéutico , Cicatrización de Heridas , Heridas y Lesiones/veterinaria , Animales , Animales de Zoológico , Enfermedades de los Gatos/terapia , Gatos , Bovinos , Enfermedades de los Bovinos/terapia , Quitosano , Enfermedades de los Perros/terapia , Perros , Japón , Heridas y Lesiones/terapia
12.
Comb Chem High Throughput Screen ; 3(6): 497-508, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11121518

RESUMEN

The appropriate selection of the mobile phase facilitated the use cellulose tris(3,5-dichlorophenylcarbamate (CDCPC) as a chiral stationary phase (CSP) during high-performance liquid chromatography (HPLC). A preliminary evaluations of this material indicated its very high chiral resolving ability toward many analytes of different chemical and pharmacological groups. Some chemicals and drugs containing two centers of chirality were also successfully resolved into all possible stereoisomers. The applicability of CDCPC for enantioseparations in capillary liquid chromatography was also shown giving promising prospects for the screening of novel biologically active compounds (which may be also synthesized based on combinatorial strategies) for their enantiomeric composition.


Asunto(s)
Carbamatos , Celulosa/análogos & derivados , Indicadores y Reactivos , Fenilcarbamatos , Cromatografía Líquida de Alta Presión , Electroforesis Capilar , Estereoisomerismo
13.
Free Radic Res ; 21(6): 399-408, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7834054

RESUMEN

Nitrogen dioxide less than 100 ppm in air induced lipid peroxidation of liposome composed of 1-palmitoyl-2-arachidonylphosphatidylcholine as assessed by thiobarbituric acid reactivity. The nitrogen dioxide-induced lipid peroxidation was enhanced by cysteine, glutathione and bovine serum albumin. While the activity of nitrogen dioxide in air to induce single strand breaks of supercoiled plasmid DNA was low, the breaking was remarkably enhanced by cysteine, glutathione and bovine serum albumin. ESR spin trapping using 5,5-dimethyl-1-pyrroline N-oxide showed that certain strong oxidant(s) were generated by interaction of nitrogen dioxide and cysteine. The spin trapping using 3,5-dibromo-4-nitrosobenzene-sulfonate suggested that sulfur-containing radicals were generated by interaction of nitrogen dioxide and cysteine or glutathione. Hence, certain sulfur-containing radicals generated by the interaction which could effectively induce lipid peroxidation and DNA strand breaks.


Asunto(s)
Cisteína , Daño del ADN , Glutatión , Peroxidación de Lípido , Liposomas , Dióxido de Nitrógeno , Plásmidos/efectos de los fármacos , 1,2-Dipalmitoilfosfatidilcolina/química , Cisteína/farmacología , Sinergismo Farmacológico , Espectroscopía de Resonancia por Spin del Electrón , Glutatión/farmacología , Cinética , Peroxidación de Lípido/efectos de los fármacos , Dióxido de Nitrógeno/farmacología , Éteres Fosfolípidos/química , Albúmina Sérica Bovina , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis
14.
J Chromatogr A ; 694(2): 347-54, 1995 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-7704190

RESUMEN

The calculation of interaction energies between cellulose trisphenylcarbamate (CTPC) and enantiomers of (+/-)-trans-stilbene oxide (1) and (+/-)-trans-1,2-diphenylcyclopropane (2) was performed using QUANTA/CHARMm and MOLECULAR INTERACTION programs to gain an insight into the chiral recognition mechanism of phenylcarbamate derivatives of cellulose. The structure of CTPC was optimized with the CHARMm force field based on the proposed structure of CTPC by X-ray analysis. In chromatographic enantioseparation on CTPC, 1 was completely resolved (alpha = 1.46) and the (R,R)-(+)-isomer eluted first followed by the (S,S)-(-)-isomer, but 2 was not resolved (alpha approximately 1). The results of calculation of interaction energies between CTPC and the enantiomers 1 suggested that the most important adsorbing site of CTPC for 1 may be the NH protons of the carbamate moieties at the 3-position of glucose units, and the (S,S)-(-)-isomer of 1 may interact more closely than the (R,R)-(+)-isomer with CTPC. In contrast, there was little difference in the minimum interaction energies between the enantiomers 2. These calculations agreed with the observed results for the chromatographic resolution on CTPC.


Asunto(s)
Carbamatos/química , Celulosa , Fenilcarbamatos , Conformación de Carbohidratos , Secuencia de Carbohidratos , Simulación por Computador , Datos de Secuencia Molecular , Estereoisomerismo , Termodinámica
15.
Anat Embryol (Berl) ; 190(1): 21-8, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7527193

RESUMEN

The process of palate fusion was examined in 13- and 14-day-old mouse fetuses by using in situ staining for nuclear DNA fragmentation (TUNEL method) and immunofluorescent staining for keratin, with special reference to the disruption of the midline epithelial seam. TUNEL-positive cells were found in the disappearing midline seam and the oral and nasal epithelial triangles at some late stages of palate fusion, but not in the palatal shelves prior to contact or in the intact midline epithelial seam. It seems that DNA fragmentation or apoptosis is required for the midline epithelial seam to disrupt, but may not be necessary for initial contact of palatal shelves or for the epithelial fusion of opposing palatal shelves. A similar sign of apoptotic cell death was observed in the disappearing epithelial seam between the fusing nasal septum and dorsal palate. We have demonstrated that apoptotic programmed cell death does occur at some stages of palate fusion, although the present results do not exclude the possibility of epithelial-mesenchymal transformation and the oral and nasal migration of midline epithelial cells.


Asunto(s)
ADN/análisis , Feto/química , Hueso Paladar/citología , Hueso Paladar/embriología , Animales , Apoptosis , Movimiento Celular/fisiología , Femenino , Feto/citología , Técnica del Anticuerpo Fluorescente , Histocitoquímica , Queratinas/análisis , Ratones , Ratones Endogámicos ICR , Hueso Paladar/química
16.
Arch Oral Biol ; 38(5): 405-13, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8392326

RESUMEN

The effects of silicic acid, silica and clay minerals on the conversion of amorphous calcium phosphate to hydroxyapatite (HAP) were studied in vitro by a pH drop method. At a concentration range of 0.01-0.1 mM. silicic acid stimulated the rate of HAP transformation by about 30-40%. Silica stimulated the rate of HAP transformation by 33-43% at a concentration range of 0.05-1.5 mg/ml. The clay minerals, i.e. kaolin and talc, also stimulated the rate of HAP transformation by 40-90% at a concentration range of 0.4-10 mg/ml, but mica inhibited the reaction markedly at 10 mg/ml. The distribution of silicon in human supragingival dental calculus was studied by an electron-probe microanalyser. We found localized silicon distribution on the oral surface of the calculus. Such silicon-rich areas always contained silicon either alone or together with magnesium, aluminium, potassium, calcium and iron. This implies that the silicon-rich area may be opal and mica. Because silicic acid, silica, kaolin and talc stimulated and mica inhibited the in vitro calcium phosphate precipitation, it is possible that these silicon-rich areas may regulate the formation of the dental calculus.


Asunto(s)
Silicatos de Aluminio/química , Fosfatos de Calcio/química , Minerales/química , Ácido Silícico/química , Dióxido de Silicio/química , Adulto , Anciano , Calcio/análisis , Calcio/química , Quelantes/química , Precipitación Química , Niño , Arcilla , Cálculos Dentales/química , Cálculos Dentales/ultraestructura , Durapatita , Microanálisis por Sonda Electrónica , Femenino , Humanos , Concentración de Iones de Hidrógeno , Hidroxiapatitas/química , Masculino , Persona de Mediana Edad , Fosfatos/química , Fósforo/análisis , Silicio/análisis
17.
Arch Oral Biol ; 31(10): 639-41, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-2957984

RESUMEN

This collagen was partially dissolved when suspended in solutions containing water-extractable components from bis-GMA-based resins (WECR) for 120 h at 37 degrees C. The WECR may cause changes in collagen conformation; similar effects may occur in dentine collagen exposed to the resins during restoration.


Asunto(s)
Acrilatos/farmacología , Colágeno/metabolismo , Resinas Compuestas/farmacología , Metacrilatos/farmacología , Tendón Calcáneo/metabolismo , Aminoácidos/análisis , Animales , Bisfenol A Glicidil Metacrilato , Bovinos , Técnicas In Vitro , Solubilidad
18.
Arch Oral Biol ; 39(7): 595-8, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7945018

RESUMEN

Using an electron-probe microanalyser, the distribution of silicon and other elements in supragingival dental calculus in domestic Japanese monkeys (Macaca fuscata) was studied. In two out of four monkeys kept in animals centres, a localized silicon distribution was found in both fracture and oral surfaces of the calculi. The silicon-rich area consisting of silicon alone resembled opal, but the areas containing silicon and other metal ions such as magnesium, aluminium, potassium and iron resembled clay minerals. In eight domestic monkeys, including the four animals described above, abundant calculus deposits were found. However, in four captured wild monkeys and in one which had been kept for less than a year at an animal centre, no dental calculus was found. There was almost no dental plaque accumulation in captured wild monkeys. It is suggested that calculus formation in Japanese monkeys is dependent on length of exposure to a commercial diet.


Asunto(s)
Animales de Laboratorio/fisiología , Animales Salvajes/fisiología , Cálculos Dentales/química , Silicio/análisis , Alimentación Animal/efectos adversos , Animales , Calcio/análisis , Cálculos Dentales/etiología , Placa Dental/química , Placa Dental/etiología , Durapatita/química , Microanálisis por Sonda Electrónica , Femenino , Macaca , Magnesio/análisis , Masculino , Fósforo/análisis
19.
J Pharm Biomed Anal ; 14(8-10): 1295-303, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8818048

RESUMEN

Chiral recognition abilities of a recently developed new type of cellulose phenylcarbamates were studied. These chiral stationary phases (CSPs) simultaneously contain both electron-withdrawing (Cl) and electron-donating (CH3) substituents on the phenyl moiety. Chiral pharmaceuticals which belong to the various pharmacological groups (sedatives, hypnotics, anticonvulsants, Ca2+ channel blockers, beta-blockers, antitusives, antihystaminics, choleretics, diuretics, antimycotics, etc) were resolved to enantiomers. These new CSPs sometimes exhibit alternative chiral recognition ability to that most successful commercially available cellulosic CSP Chiralcel-OD and can be used as a good complement to it in analytical and preparative scale enantioseparations.


Asunto(s)
Carbamatos , Celulosa/análogos & derivados , Preparaciones Farmacéuticas/análisis , Antagonistas Adrenérgicos beta/análisis , Ansiolíticos/análisis , Antifúngicos/análisis , Barbitúricos/análisis , Benzodiazepinas/análisis , Cromatografía Líquida de Alta Presión/métodos , Dihidropiridinas/análisis , Antagonistas de los Receptores Histamínicos H1/análisis , Hipnóticos y Sedantes/análisis , Imidazoles/análisis , Propanolaminas/análisis , Piridinas/análisis , Estereoisomerismo , Vasodilatadores/análisis
20.
J Cardiovasc Surg (Torino) ; 30(4): 609-13, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2550468

RESUMEN

With scanning electron microscopy, we examined the behavior of platelets and leukocytes on the luminal surface of small caliber polyurethane grafts implanted into small arteries of dogs. Thirty-five grafts were implanted to the carotid and/or femoral arteries. The animals were treated with aspirin and/or DN9693, an inhibitor of phosphodiesterase. In the group treated with aspirin (40 mg/kg i.v.), the deposition of platelets on the luminal surface of the implanted polyurethane grafts was suppressed and the luminal surface was covered with adherent leukocytes. Fibrin nets were formed on the adherent leukocytes. In addition, the adhesion of leukocytes on the grafts was considerably suppressed in the group treated with DN9693 (50 micrograms/kg/min i.v.), and the formation of fibrin nets was markedly reduced. In contrast, in the control group the luminal surface was covered with numerous platelets and some leukocytes, which formed thrombi. These findings suggest that leukocytes adhere primarily to the prosthetic graft and play an important role in the initiation of fibrin formation.


Asunto(s)
Plaquetas/fisiología , Prótesis Vascular , Oclusión de Injerto Vascular/etiología , Leucocitos/fisiología , Poliuretanos , 3',5'-AMP Cíclico Fosfodiesterasas/antagonistas & inhibidores , 3',5'-AMP Cíclico Fosfodiesterasas/uso terapéutico , Animales , Aspirina/uso terapéutico , Arterias Carótidas/cirugía , Adhesión Celular , Perros , Arteria Femoral/cirugía , Fibrina/biosíntesis , Oclusión de Injerto Vascular/prevención & control , Microscopía Electrónica de Rastreo , Inhibidores de Agregación Plaquetaria/uso terapéutico , Quinazolinas/uso terapéutico
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