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1.
Archaeol Anthropol Sci ; 16(1): 3, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38098511

RESUMEN

Understanding the factors shaping human crania has long been a goal of biological anthropology, and climate, diet, and population history are three of the most well-established influences. The effects of these factors are, however, rarely compared within a single, variable population, limiting interpretations of their relative contribution to craniofacial form. Jomon prehistoric foragers inhabited Japan throughout its climatic and ecological range and developed correspondingly varied modes of subsistence. We have previously demonstrated that a large sample of Jomon crania showed no clear climatic pattern; here, we examine variation in Jomon crania in more detail to determine if dietary factors and/or population history influence human intrapopulation variation at this scale. Based on well-established archaeological differences, we divide the Jomon into dietary groups and use geometric morphometric methods to analyse relationships between cranial shape, diet, and population history. We find evidence for diet-related influences on the shape of the neurocranium, particularly in the temporalis region. These shape differences may be interpreted in the context of regional variation in the biomechanical requirements of different diets. More experimental biomechanical and nutritional evidence is needed, however, to move suggested links between dietary content and cranial shape from plausible to well-supported. In contrast with the global scale of human variation, where neutral processes are the strongest influence on cranial shape, we find no pattern of population history amongst individuals from these Jomon sites. The determinants of cranial morphology are complex and the effect of diet is likely mediated by factors including sex, social factors, and chronology. Our results underline the subtlety of the effects of dietary variation beyond the forager/farmer dichotomy on cranial morphology and contribute to our understanding of the complexity of selective pressures shaping human phenotypes on different geographic scales. Supplementary Information: The online version contains supplementary material available at 10.1007/s12520-023-01901-6.

2.
Hand Surg Rehabil ; 40(4): 369-376, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33895422

RESUMEN

Digital nerve block is a common procedure with several techniques, including the traditional digital nerve block, transthecal digital nerve block, and single subcutaneous palmar digital nerve block. This review aimed to evaluate the efficacy of these three methods. A systematic search was performed in the PubMed, Scopus, and Cochrane Library databases. The risk of bias of the studies was assessed using the Cochrane Collaboration's tool for assessing the risk of bias and the Risk of Bias Assessment Tool for Non-Randomized Studies. Fourteen prospective randomized controlled studies and one prospective comparative study were included. The three methods of digital block showed similar onset times, durations, injection pain and incidence of incomplete anesthesia. This review confirmed that all three methods of digital block are equally effective. Considering that patients prefer a single injection and the potential risk of complications, the single subcutaneous digital block could be more widely used.


Asunto(s)
Anestésicos Locales , Bloqueo Nervioso , Humanos , Inyecciones Subcutáneas , Bloqueo Nervioso/métodos , Dimensión del Dolor , Estudios Prospectivos
3.
Transplant Proc ; 50(10): 3255-3257, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30577194

RESUMEN

INTRODUCTION: Recently, more and more generic drugs have been used for immunosuppressive drugs in the field of organ transplantation. Some reports have indicated that blood concentration of most generic drugs is difficult to maintain stability, and it may cause the difference in graft survival of transplanted organs between original drugs and generic drugs. In this article, we report the cases could not maintain blood concentration of generic drugs of mycophenolate mofetil (MMF). RESULTS: In 4 cases out of 5 cases that we had to change original MMF to generic MMF, there were cases that blood concentration level was not stabilized. There were possibility that the lowered blood concentration level of MMF caused a rejection, in two cases. Mean MMF trough level was decreased from 3.6 ± 1.9 µg/mL to 0.6 ± 0.4 µg/mL. Due to the early detection, it did not become severe or failure of graft function, however, we cannot deny the possibilities that side effects were increased and rejection rose. In these cases, we discontinued to use the generic drugs thereafter due to unstable plasma concentration of MMF. DISCUSSION: Some reports have indicated that failure to maintain plasma concentration of MMF leads to rejection. Therefore, maintenance of effective plasma concentration and prevention of rejection are essential to long-term graft survival in kidney transplant. CONCLUSION: Generic drug formulations may exhibit differences in effects and absorption compared to the brand-name drug. If the generic drug should be used, patients should be closely monitored.


Asunto(s)
Sustitución de Medicamentos/efectos adversos , Medicamentos Genéricos/efectos adversos , Inmunosupresores/efectos adversos , Inmunosupresores/sangre , Trasplante de Riñón , Ácido Micofenólico/efectos adversos , Adulto , Niño , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Femenino , Rechazo de Injerto/prevención & control , Supervivencia de Injerto , Humanos , Japón , Masculino , Persona de Mediana Edad , Ácido Micofenólico/sangre
5.
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
6.
Protein Eng Des Sel ; 21(12): 737-44, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18987131

RESUMEN

A family I.3 lipase from Pseudomonas sp. MIS38 (PML) contains three Ca(2+)-binding sites (Ca1-Ca3) in the N-catalytic domain. Of them, the Ca1 site is formed only in an open conformation. To analyze the role of these Ca(2+)-binding sites, three mutant proteins D157A-PML, D275A-PML and D337A-PML, which are designed to remove the Ca1, Ca2 and Ca3 sites, respectively, were constructed. Of them, the crystal structures of D157A-PML and D337A-PML in a closed conformation were determined. Both structures are nearly identical to that of the wild-type protein, except that the Ca3 site is missing in the D337A-PML structure. D157A-PML was as stable as the wild-type protein. Nevertheless, it exhibited little lipase and very weak esterase activities. D275A-PML was less stable than the wild-type protein by approximately 5 degrees C in T(1/2). It exhibited weak but significant lipase and esterase activities when compared with the wild-type protein. D337A-PML was also less stable than the wild-type protein by approximately 5 degrees C in T(1/2) but was fully active. These results suggest that the Ca1 site is required to make the active site fully open by anchoring lid 1. The Ca2 and Ca3 sites contribute to the stabilization of PML. The Ca2 site is also required to make PML fully active.


Asunto(s)
Calcio/metabolismo , Dominio Catalítico , Lipasa/química , Lipasa/metabolismo , Pseudomonas/enzimología , Dicroismo Circular , Cristalografía por Rayos X , Lipasa/genética , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Mutación , Desnaturalización Proteica , Ingeniería de Proteínas , Estabilidad Proteica , Temperatura
7.
J Synchrotron Radiat ; 15(Pt 3): 269-72, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18421156

RESUMEN

To investigate quantitatively the effects of stirring on protein crystallization, a new stirring system which can agitate a protein solution, approximately 100 nl, by providing Hagen-Poiseuille flow has been successfully developed. In addition, this new stirring system provides flow with a well defined pattern and velocity. Using this system, hen egg-white lysozyme was crystallized in 100-200 nl solutions while being stirred. The optimum stirring conditions for lysozyme crystals have been explored by evaluating the Reynolds (Re) number and the crystals obtained. Intermittent flow, as well as a low Re number, was found to contribute significantly to the growth of a smaller number of larger crystals.


Asunto(s)
Muramidasa/química , Cristalización , Soluciones
8.
Clin Nephrol ; 66(6): 405-10, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17176911

RESUMEN

AIM: Recent studies have indicated that reactive oxygen species (ROS) play a role in the pathogenesis of glomerular injury leading to proteinuria in nephrotic syndrome. In the present investigation, we examined the effects of the radical scavenger edaravone administered at various time points to rats with puromycin nephrosis. MATERIALS AND METHODS: 35 Wistar rats were divided into five groups: treatment with puromycin aminonucleoside (PAN) alone, treatment with PAN followed by edaravone in the early period, treatment with PAN followed by edaravone administration in the late period, treatment with PAN and administration of edaravone for the whole experimental period, and untreated controls. On Days 3, 6 and 9, urinary protein excretion was measured. The levels of glomerular thiobarbituric acid-reactive substance (TBArs) were determined in all animals on Day 10. RESULTS: On Day 9, rats that had been administered edaravone showed reduced urinary protein excretion and reduced glomerular TBArs. In particular, edaravone administration in the late period, during which proteinuria was most acute, had the effect of reducing the severity of proteinuria. Glomerular TBArs were suppressed to the control level. Our results indicate that edaravone exerts a protective effect in the acute phase of PAN nephrosis when administered as antioxidant therapy at the onset of proteinuria. CONCLUSIONS: Edaravone can ameliorate urinary protein excretion after the onset of proteinuria in nephrotic syndrome.


Asunto(s)
Antipirina/análogos & derivados , Depuradores de Radicales Libres/uso terapéutico , Nefrosis/prevención & control , Animales , Antipirina/uso terapéutico , Modelos Animales de Enfermedad , Edaravona , Estudios de Seguimiento , Glomérulos Renales/efectos de los fármacos , Glomérulos Renales/metabolismo , Glomérulos Renales/patología , Masculino , Nefrosis/inducido químicamente , Nefrosis/patología , Puromicina/toxicidad , Ratas , Ratas Wistar , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Resultado del Tratamiento
9.
J Oral Rehabil ; 33(7): 514-9, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16774510

RESUMEN

This study investigated the sagittal condylar path during protrusive and lateral excursions by analysing the actually measured jaw movement data and re-evaluated the setting of the sagittal condylar path inclination in consideration of Fischer's angle. Protrusive and lateral excursions of 10 healthy subjects were measured using a three-dimensional mandibular movement analysing system. Condylar path inclinations at the hinge-axis point and the corresponding external point laterally extending from the condyle were evaluated in the sagittal plane. Fischer's angle was defined as the difference between the sagittal condylar inclinations during protrusive and lateral excursions on the non-working side, by keeping the corresponding horizontal distance from the intercuspal position (ICP) equivalent at the incisal point. Analysis was performed at three different magnitudes of excursions, where the incisal point was located at 1, 3 and 5 mm away from the ICP. There was no significant difference in the sagittal condylar path inclination or the Fischer's angle between two condylar reference points. However, they were significantly different across the three different magnitudes of excursions for both condylar reference points, i.e. sagittal condylar path inclination (P = 0.003 for protrusive excursion, and P < 0.001 for lateral excursion respectively; two-way repeated-measures anova), and Fischer's angle (P = 0.013, two-way repeated-measures anova) became smaller as the incisal point became distant from the ICP. Moreover, 3- and 5-mm eccentric positions were included in the 95% CI where Fischer's angle equals zero and were considered to be clinically acceptable to adjust the sagittal condylar inclination on the semiadjustable articulators.


Asunto(s)
Cóndilo Mandibular/fisiología , Articulación Temporomandibular/fisiología , Adulto , Articuladores Dentales , Oclusión Dental , Humanos , Imagenología Tridimensional/métodos , Movimiento/fisiología
10.
J Oral Rehabil ; 32(8): 598-605, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16011639

RESUMEN

This study evaluates the bonding characteristics of a lithium disilicate-based ceramic material (IPS Empress 2). Two sizes of disk specimens of the material were made, and three groups of disk pairs were separately surface-prepared using three techniques; etching with phosphoric acid, etching with hydrofluoric acid, and air-abrasion with alumina. Each group was further divided into four sub-groups; group (i) was bonded with the Variolink II composite, (ii) was treated with the Monobond-S silane primer and bonded with the Variolink II composite, (iii) was bonded with the Super-Bond acrylic adhesive and (iv) was treated with the Porcelain Liner M silane primer and bonded with the Super-Bond acrylic adhesive. Shear bond strengths were determined before and after 100 000 thermocycles. Bond strength varied from 10.6 to 71.5 MPa before thermocycling, whereas post-thermocycling bond strength ranged from 0 to 61.2 MPa. Among the three surface preparations, hydrofluoric acid etching (HF) was most effective in enhancing bond strength of both luting materials, especially for unsilanized specimens. Application of the silane primer elevated bond strength of both luting agents regardless of surface preparation method. It can be concluded, for both luting agents, that durable bond to the Empress 2 ceramic material can be achieved through the combined application of HF and the proprietary silane primer.


Asunto(s)
Cementación , Cerámica , Cementos Dentales , Cementos de Resina , Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios , Humanos , Ensayo de Materiales , Resistencia al Corte , Silanos
11.
Theor Appl Genet ; 110(7): 1203-9, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15791451

RESUMEN

Chalcone synthase (CHS), the key enzyme in the flavonoid biosynthesis pathway, is encoded by a multigene family, CHS1-CHS8 and dCHS1 in soybean. A tandem repeat of CHS1, CHS3 and CHS4, and dCHS1 that is believed to be located in the vicinity comprises the I locus that suppresses coloration of the seed coat. This study was conducted to determine the location of all CHS members by using PCR-based DNA markers. Primers were constructed based on varietal differences in either the nucleotide sequence of the 5'-upstream region or the first intron of two cultivars, Misuzudaizu, with a yellow seed coat (II), and Moshidou Gong 503, with a brown seed coat (ii). One hundred and fifty recombinant inbred lines that originated from a cross between these two cultivars were used for linkage mapping together with 360 markers. Linkage mapping confirmed that CHS1, CHS3, CHS4, dCHS1, and the I locus are located at the same position in molecular linkage group (MLG) A2. CHS5 was mapped at a distance of 0.3 cM from the gene cluster. CHS2 and CHS6 were located in the middle region of MLGs A1 and K, respectively, while CHS7 and CHS8 were found at the distal end of MLGs D1a and B1, respectively. Phylogenetic analysis indicated that CHS1, CHS3, CHS4, and CHS5 are closely related, suggesting that gene duplication may have occurred repeatedly to form the I locus. In addition, CHS7 and CHS8 located at the distal end and CHS2, CHS6, and CHS members around the I locus located around the middle of the MLG are also related. Ancient tetraploidization and repeated duplication may be responsible for the evolution of the complex genetic loci of the CHS multigene family in soybean.


Asunto(s)
Aciltransferasas/genética , Mapeo Cromosómico , Glycine max/genética , Familia de Multigenes/genética , Filogenia , Semillas/fisiología , Secuencia de Bases , Cruzamientos Genéticos , Cartilla de ADN , Marcadores Genéticos , Datos de Secuencia Molecular , Técnicas de Amplificación de Ácido Nucleico , Pigmentación/fisiología , Polimorfismo de Longitud del Fragmento de Restricción , Semillas/genética , Alineación de Secuencia , Análisis de Secuencia de ADN , Glycine max/fisiología
12.
Radiat Prot Dosimetry ; 116(1-4 Pt 2): 553-7, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16604697

RESUMEN

An irradiation field of high-energy neutrons produced in the forward direction from a thick tungsten target bombarded by 500 MeV protons was arranged at the KENS spallation neutron source facility. In this facility, shielding experiment was performed with an ordinary concrete shield of 4 m thickness assembled in the irradiation room, 2.5 m downstream from the target centre. Activation detectors of bismuth, aluminium, indium and gold were inserted into eight slots inside the shield and attenuations of neutron reaction rates were obtained by measurements of gamma-rays from the activation detectors. A MARS14 Monte Carlo simulation was also performed down to thermal energy, and comparisons between the calculations and measurements show agreements within a factor of 3. This neutron field is useful for studies of shielding, activation and radiation damage of materials for high-energy neutrons, and experimental data are useful to check the accuracies of the transmission and activation calculation codes.


Asunto(s)
Materiales de Construcción/análisis , Neutrones Rápidos , Modelos Estadísticos , Aceleradores de Partículas/instrumentación , Protección Radiológica/instrumentación , Protección Radiológica/métodos , Radiometría/métodos , Simulación por Computador , Japón , Transferencia Lineal de Energía , Ensayo de Materiales/métodos , Método de Montecarlo , Dosis de Radiación , Programas Informáticos
13.
J Oral Rehabil ; 31(10): 985-90, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15387839

RESUMEN

The purpose of the current study was to evaluate the clinical performance of two composite materials used for filling anterior cavity preparations. A total of 100 class V cavities of anterior tooth were restored with two different composite materials (Palfique Estelite and Palfique Toughwell, 50 cavities each, respectively) in combination with the same bonding agent (Mac Bond II). Colour match, cavosurface marginal discolouration, recurrent caries, wear, marginal integrity and surface texture were evaluated clinically for all restorations on the basis of the United States Public Health Service (USPHS) criteria immediately after insertion (baseline), after 6 months and after 1 year. In the comparison of baseline to 1-year evaluation, the Palfique Toughwell material showed significant changes in all factors except recurrent caries. The Palfique Estelite material, however, showed neither significant cavosurface marginal discolouration nor recurrent caries. No significant difference (P > 0b05) was observed between the two materials in clinical performance after 1 year, with the exception of caries rate, which was found to be significantly lower in the Palfique Estelite material. It was concluded that both composites were clinically reliable materials when used for anterior class V restorations.


Asunto(s)
Resinas Compuestas , Caries Dental/terapia , Restauración Dental Permanente/métodos , Adaptación Marginal Dental , Alisadura de la Restauración Dental , Femenino , Estudios de Seguimiento , Humanos , Incisivo , Masculino , Coloración de Prótesis , Estadísticas no Paramétricas
14.
J Oral Rehabil ; 31(8): 770-4, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15265213

RESUMEN

The purpose of the current study was to evaluate the effect of two-component ceramic primers on the bond strength of a composite material joined to a sintered porcelain material. Two sizes of porcelain discs (VMK 68; 10 and 8 mm in diameter by 2.5 mm thick) were ground (No. 1000 SiC), and surface-conditioned using one of the following systems: (i) unprimed, (ii) Liquid A of the Porcelain Liner M material (PLM-A), (iii) Liquid B of Porcelain Liner M (PLM-B), (iv) Liquids A and B of Porcelain Liner M (PLM-AB), (v) Liquid A of the Tokuso Ceramics Primer material (TCP-A), (vi) Liquid B of Tokuso Ceramics Primer (TCP-B) and (vii) Liquids A and B of Tokuso Ceramics Primer (TCP-AB). All specimens were bonded with the Bistite II dual-cured composite luting agent, and shear bond strengths were determined both after 24 h immersion in water and after subsequent thermocycling (4-60 degrees C, 1 min each, 20,000 cycles). Of the seven groups assessed, two groups (PLM-AB and TCP-AB) showed the greatest bond strength both before (30.7 MPa for PLM-AB and 29.7 MPa for TCP-AB) and after (19.7 MPa for PLM-AB and 22.4 MPa for TCP-AB) thermocycling (P < 0.05). No significant differences were found between the PLM-AB and TCP-AB groups regardless of the application of thermocycling (P > 0.05). It can be concluded that both of the acid-catalysed two-liquid ceramic primers showed superior bonding to the unhydrolysed single-liquid silane agents (PLM-B and TCP-A) when the feldspathic porcelain was bonded with the Bistite II luting composite.


Asunto(s)
Recubrimiento Dental Adhesivo , Cementos Dentales , Ensayo de Materiales , Silanos , Análisis de Varianza , Porcelana Dental
15.
J Oral Rehabil ; 31(7): 689-94, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15210031

RESUMEN

The relative strengths of ceramic-to-metal and composite-to-metal bonds were compared after prolonged thermocycling. A total of 104 cast discs were produced from a gold alloy (Pontor LFC). A ceramic material (Duceragold) was fused to 24 discs to assess the strength of the metal-ceramic bond. An indirect composite material (New Metacolor Infis) was bonded to the remaining discs after surface preparation by Rocatec tribochemical coating, tin plating and priming with a phosphate conditioner [10-methacryloyloxydecyl dihydrogen phosphate (MDP), Cesead II], priming with a thione conditioner (V-Primer) or no treatment (unprimed control). Shear bond strengths were determined before and after thermocycling at 20,000 and 100,000 cycles. Pre-thermocycling bond strengths were ranked in the order: metal-ceramic (40.5 MPa); Rocatec treatment (33.1 MPa) and tin plating-MDP (31.0 MPa); V-Primer (20.9 MPa); and control (11.9 MPa). The bond strengths of the first three groups were not significantly different after 20,000 thermocycles, whereas those of the V-Primer and control groups were significantly reduced. After extended thermocycling (100,000 cycles) the metal-ceramic group had the highest mean shear bond strength (28.5 MPa; P < 0.05), followed by the Rocatec (23.9 MPa) and tin plating-MDP (22.1 MPa) groups. The metal-ceramic bond was the most durable, although its strength was reduced by 29.6% after extended thermocycling. On the basis of these results, we recommend the Rocatec and tin plating-MDP systems for composite-to-metal bonding. Metal-ceramic bonding, however, is superior to metal-composite bonding within the limitation of the current experiment.


Asunto(s)
Resinas Compuestas/química , Recubrimiento Dental Adhesivo/métodos , Porcelana Dental/química , Aleaciones de Oro/química , Análisis de Varianza , Cementos Dentales/química , Calor , Humanos , Ensayo de Materiales/métodos , Resistencia al Corte , Propiedades de Superficie , Termodinámica
16.
Plant Mol Biol ; 56(4): 563-71, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15630620

RESUMEN

Cassava mosaic disease (CMD) is a viral disease of the important tropical staple crop cassava (Manihot esculenta) and preferred management involves use of host-plant resistance. The best available resistance is controlled by a single dominant gene. Serial analysis of gene expression (SAGE) was used to analyze the gene expression pattern in a bulk of 40 each of CMD resistant and susceptible genotypes drawn from a gene mapping progeny. Messenger RNA used for the SAGE analysis came from plants that were exposed to heavy disease pressure over a period of 2 years in the field. A total of 12,786 tags were studied, divided into 5733 and 7053 tags from the resistant and susceptible genotypes, respectively. Tag annotation was by PCR amplification using the tag sequence as sense primer and 4000 cassava ESTs generated from the bulk of CMD resistant genotypes. Annotation of more than 30 differentially expressed tags revealed several genes expressed during systemic acquired resistance (SAR) in plants and other genes involved in cell-to-cell and cytoplasm-to-nucleus virus trafficking. Differential expression of the most abundantly expressed tag, corresponding to a beta-tubulin gene, was confirmed by Northern Analysis. RFLP analysis of the tags in the parents and bulks of the CMD mapping progeny revealed only one tag, a WRKY transcription factor, associated with the region bearing the dominant CMD gene.


Asunto(s)
Perfilación de la Expresión Génica , Manihot/genética , Enfermedades de las Plantas/genética , Virus de Plantas/crecimiento & desarrollo , Secuencia de Bases , Northern Blotting , ADN Complementario/química , ADN Complementario/genética , Etiquetas de Secuencia Expresada , Regulación de la Expresión Génica de las Plantas , Biblioteca de Genes , Genotipo , Manihot/virología , Enfermedades de las Plantas/virología , ARN de Planta/genética , ARN de Planta/metabolismo , Análisis de Secuencia de ADN
17.
J Oral Rehabil ; 30(10): 1015-21, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12974862

RESUMEN

The purpose of this study was to evaluate the influence of visible-light exposure on water absorption, solubility and colour stability of dual-curable luting composites. Using eight dual-curable luting composites (2bond2, Bistite II, G-CERA Cosmotech II, Imperva Dual, Linkmax, Lute-It, Panavia Fluoro Cement and Variolink II), disk specimens were prepared by the following two methods: (i) dual-cured specimens; exposed with visible-light from a light-curing unit, and (ii) chemical-cured specimens; chemically polymerized without exposure. Five specimens were produced for each material and curing mode. Water absorption and solubility were determined according to standardized testing methods, and the data were compared using analysis of variance (ANOVA) and contrasts. With regard to colour stability, the colour difference (DeltaE*) values between 24 h and the other immersion periods (1, 2, 3, 4, 8, 12, 16, 20 and 24 weeks) were calculated and then analysed by repeated measure ANOVA. The dual-cured specimens exhibited significantly lower solubility values than the chemical-cured specimens except for the Lute-It material. The dual-cured Linkmax material exhibited the lowest solubility (0.51 +/- 0.01 microg mm(-3)) and the lowest DeltaE* value after 24 weeks (2.64 +/- 0.39). The dual-curable luting composites should be light-exposed after seating of restorations in order to reduce water absorption and solubility, and to improve colour stability.


Asunto(s)
Resinas Compuestas/efectos de la radiación , Luz , Coloración de Prótesis/normas , Absorción , Análisis de Varianza , Resinas Compuestas/metabolismo , Resinas Compuestas/normas , Polímeros , Solubilidad , Agua/metabolismo
18.
Mol Genet Genomics ; 270(2): 181-9, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12955499

RESUMEN

Treatment with cyclic AMP (cAMP) induces appressorium formation in the phytopathogenic fungus Magnaporthe grisea, the causative agent of rice blast disease. In a search for the M. grisea genes responsible for appressorium formation and host invasion, SAGE (Serial Analysis of Gene Expression) was carried out using mRNA isolated from fungal conidia germinating in the presence and absence of cAMP. From cAMP-treated conidia 5087 tags including 2889 unique tags were isolated, whereas untreated conidia yielded 2342 unique tags out of total of 3938. cAMP treatment resulted in up- and down-regulation of genes corresponding to 57 and 53 unique tags, respectively. Upon consultation of EST/cDNA databases, 22 tags with higher representation in cAMP-treated conidia were annotated with putative gene names. Furthermore, 28 tags corresponding to cAMP-induced genes could be annotated with the help of the recently published genome sequence of M. grisea. cAMP-induced genes identified by SAGE included many genes that have not been described so far, as well as a number of genes known to be involved in pathogenicity, e.g. MPG1, MAS1 and MAC1. RT-PCR of 13 randomly selected genes confirmed the SAGE results, verifying the fidelity of the SAGE data.


Asunto(s)
Genes Fúngicos , Magnaporthe/genética , Secuencia de Bases , AMP Cíclico/farmacología , ADN de Hongos/genética , Perfilación de la Expresión Génica , Regulación Fúngica de la Expresión Génica/efectos de los fármacos , Genes Fúngicos/efectos de los fármacos , Magnaporthe/efectos de los fármacos , Magnaporthe/crecimiento & desarrollo , Magnaporthe/patogenicidad , Oryza/microbiología , Enfermedades de las Plantas/microbiología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
19.
J Oral Rehabil ; 30(8): 832-6, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12880408

RESUMEN

This study determined the hardness, solubility and curing depth of a new photo-activated composite polymerized with three different laboratory photo-curing units for the purpose of evaluating the post-curing properties of the material. A new photo-activated composite material for both direct and indirect applications (DiamondCrown) was polymerized with three photo-curing units equipped with the following light sources: (i) two halogen lamps (DiamondLite-VL. Halogen Light Curing Booth); (ii) two metal halide lamps (Hyper LII) and (iii) two xenon stroboscopic tubes (UniXS II). Knoop hardness, water solubility and curing depth were determined for groups of five specimens according to standardized testing methods. All data were compared using analysis of variance (anova) and Scheffe's S intervals (P < 0.05). The Knoop hardness number (KHN) generated with the metal halide unit (63.3 +/- 2.4 KHN) was statistically (P < 0.05) greater than those produced by the other two curing units. Water solubility values for both the halogen unit (2.5 +/- 0.5 microg mm(-3)) and the metal halide unit (2.5 +/- 0.5 microg mm(-3)) were significantly (P < 0.05) lower than for the xenon unit (3.8 +/- 0.5 microg mm(-3)). Of the three photo-curing units, the metal halide curing-unit consistently exhibited the greatest depth of cure. The composite material appears to be reliable, although its post-curing properties were found to be influenced by the type of curing unit.


Asunto(s)
Resinas Compuestas/química , Coronas con Frente Estético , Análisis de Varianza , Resinas Compuestas/efectos de la radiación , Fluorescencia , Halógenos , Humanos , Luz , Ensayo de Materiales , Polímeros/química , Polímeros/efectos de la radiación , Solubilidad , Resistencia a la Tracción , Agua/química
20.
J Oral Rehabil ; 30(6): 653-8, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12787464

RESUMEN

The purpose of the current study was to evaluate the bonding characteristics of super-elastic titanium-nickel (Ti-Ni) alloy castings. Disk specimens were cast from a Ti-Ni alloy (Ti-50.85Ni mol%) using an arc centrifugal casting machine. High-purity titanium and nickel specimens were also prepared as experimental references. The specimens were air-abraded with alumina, and bonded with an adhesive resin (Super-Bond C & B). A metal conditioner containing a phosphate monomer (Cesead II Opaque Primer) was also used for priming the specimens. Post-thermocycling average bond strengths (MPa) of the primed groups were 41.5 for Ti-Ni, 30.4 for Ti and 19.5 for Ni, whereas those of the unprimed groups were 21.6 for Ti, 19.3 for Ti-Ni and 9.3 for Ni. Application of the phosphate conditioner elevated the bond strengths of all alloy/metals (P < 0.05). X-ray fluorescence analysis revealed that nickel was attached to the debonded resin surface of the resin-to-nickel bonded specimen, indicating that corrosion of high-purity nickel occurred at the resin-nickel interface. Durable bonding to super-elastic Ti-Ni alloy castings can be achieved with a combination of a phosphate metal conditioner and a tri-n-butylborane-initiated adhesive resin.


Asunto(s)
Recubrimiento Dental Adhesivo , Técnica de Colado Dental/instrumentación , Cementos Dentales/química , Níquel/química , Fosfatos/química , Titanio/química , Adhesivos , Análisis de Varianza , Materiales Dentales , Humanos , Ensayo de Materiales/métodos
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