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1.
Chinese Medical Sciences Journal ; (4): 349-352, 2022.
Artículo en Inglés | WPRIM | ID: wpr-970700

RESUMEN

Autosomal recessive congenital ichthyosis (ARCI) is characterized by being born as collodion babies, hyperkeratosis, and skin scaling. We described a collodion baby at birth with mild ectropion, eclabium, and syndactyly. Whole exome sequencing showed a compound heterozygous variant c.[56C>A], p.(Ser19X) and c.[100G>A], p.(Ala34Thr) in the PNPLA1 gene [NM_001145717; exon 1]. The protein encoded by PNPLA1 acts as a unique transacylase that specifically transfers linoleic acid from triglyceride to ω-hydroxy fatty acid in ceramide, thus giving rise to ω-O-acylceramide, a particular class of sphingolipids that is essential for skin barrier function. The variant was located in the patatin core domain of PNPLA1 and resulted in a truncated protein which could disrupt the function of the protein. This case report highlights a novel compound heterozygous mutation in PNPLA1 identified in a Chinese child.


Asunto(s)
Humanos , Recién Nacido , Aciltransferasas/genética , Ceramidas/metabolismo , Colodión , Ictiosis Lamelar/genética , Lipasa/metabolismo , Mutación , Fosfolipasas/genética
2.
Journal of Zhejiang University. Science. B ; (12): 343-354, 2019.
Artículo en Inglés | WPRIM | ID: wpr-1010465

RESUMEN

Rice stripe virus (RSV) causes dramatic losses in rice production worldwide. In this study, two monoclonal antibodies (MAbs) 16E6 and 11C1 against RSV and a colloidal gold-based immunochromatographic strip were developed for specific, sensitive, and rapid detection of RSV in rice plant and planthopper samples. The MAb 16E6 was conjugated with colloidal gold and the MAb 11C1 was coated on the test line of the nitrocellulose membrane of the test strip. The specificity of the test strip was confirmed by a positive reaction to RSV-infected rice plants and small brown planthopper (SBPH), and negative reactions to five other rice viruses, healthy rice plants, four other vectors of five rice viruses, and non-viruliferous SBPH. Sensitivity analyses showed that the test strip could detect the virus in RSV-infected rice plant tissue crude extracts diluted to 1:20 480 (w/v, g/mL), and in individual viruliferous SBPH homogenate diluted to 1:2560 (individual SPBH/μL). The validity of the developed strip was further confirmed by tests using field-collected rice and SBPH samples. This newly developed test strip is a low-cost, fast, and easy-to-use tool for on-site detection of RSV infection during field epidemiological studies and paddy field surveys, and thus can benefit decision-making for RSV management in the field.


Asunto(s)
Anticuerpos Monoclonales/química , China , Cromatografía de Afinidad/métodos , Colodión/química , Coloides/química , Oro Coloide/química , Ensayo de Materiales , Membranas Artificiales , Oryza/virología , Enfermedades de las Plantas/virología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Especificidad de la Especie , Tenuivirus/aislamiento & purificación
3.
Korean Journal of Dermatology ; : 645-647, 2018.
Artículo en Coreano | WPRIM | ID: wpr-718997

RESUMEN

No abstract available.


Asunto(s)
Colodión
4.
Clinical and Experimental Vaccine Research ; : 61-66, 2017.
Artículo en Inglés | WPRIM | ID: wpr-43943

RESUMEN

PURPOSE: Nitrocellulose membrane–based filtration system (NCFS) is widely used for protein concentration. In this study, we applied NCFS for production of virus-like particle (VLP) as a vaccine candidate and evaluated yield property and immunogenicity. MATERIALS AND METHODS: Influenza VLPs were generated by baculovirus-insect cell protein expression system. NCFS and sucrose gradient ultracentrifugation were used for purification of VLP. Immunogenicity of VLP was evaluated by animal experiment. RESULTS: Influenza VLPs expressing hemagglutinin (HA) and neuraminidase proteins derived from highly pathogenic influenza virus (H5N8) were effectively produced and purified by NCFS. HA activity of VLP which correlated with antigenicity was well conserved during multiple purification steps. This NCFS based purified VLPs induced influenza virus–specific antibody responses. CONCLUSION: Our results indicate that the influenza VLP vaccine could be prepared by NCFS without loss of immunogenicity and elicit antigen-specific immune responses.


Asunto(s)
Experimentación Animal , Formación de Anticuerpos , Baculoviridae , Colodión , Filtración , Hemaglutininas , Gripe Humana , Membranas , Neuraminidasa , Orthomyxoviridae , Sacarosa , Ultracentrifugación , Vacunas
5.
Journal of Veterinary Science ; : 307-316, 2017.
Artículo en Inglés | WPRIM | ID: wpr-57417

RESUMEN

A simple and rapid immunochromatographic test strip incorporating a colloidal gold-labeled recombinant Nsp7 antigen probe was successfully developed for the detection of anti-porcine reproductive and respiratory syndrome virus (PRRSV) antibodies in swine. Recombinant Nsp7 protein of PRRSV labeled with colloidal gold was dispensed on a conjugate pad for use as the detector. Staphylococcal protein A and purified porcine anti-Nsp7 antibodies were blotted on a nitrocellulose membrane to form test and control lines, respectively. A comparison of the strip with standard diagnostic tests, enzyme-linked immunosorbent assays and immunoperoxidase monolayer assay, was also performed. The immunochromatographic test strip was shown to be of high specificity and sensitivity. Furthermore, the strip assay is rapid and easy to perform with no requirement for professional-level skills or equipment. It is suggested that the immunochromatographic test strip can be used to quickly and accurately detect PRRSV antibody and to be suitable for diagnostic purposes in the field.


Asunto(s)
Anticuerpos , Colodión , Coloides , Pruebas Diagnósticas de Rutina , Ensayo de Inmunoadsorción Enzimática , Oro Coloide , Cromatografía de Afinidad , Membranas , Síndrome Respiratorio y de la Reproducción Porcina , Virus del Síndrome Respiratorio y Reproductivo Porcino , Sensibilidad y Especificidad , Proteína Estafilocócica A , Porcinos
6.
Chinese Journal of Biotechnology ; (12): 1387-1392, 2015.
Artículo en Chino | WPRIM | ID: wpr-337482

RESUMEN

The preservation of urinary proteins on a membrane plays a vital role in biomarker research, and the efficient elution of proteins preserved on nitrocellulose membrane (NC membrane) determines the application of this method. During the heating elution procedure, we raised the temperature to reduce the intense vortexing time, and kept gentle rotating while precipitation to prevent nitrocellulose reformation. We also used SDS-PAGE and LC-MS/MS to analyze the urinary proteins prepared by heating elution procedure, intense vortexing elution procedure and acetone precipitation method. There was no degradation of proteins prepared by heating elution procedure. Compared with proteins prepared by heating elution method and acetone precipitation method, the overlapping rates of the proteins was almost the same (92.6% versus 96.8%) and the ratios of CV values (< 20%) of the proteins were both high (85.2% and 94.4%). The heating elution procedure achieved good technical reproducibility, and was much simpler and more efficient than the previous one. It can facilitate the application of the preservation of urinary proteins on membrane.


Asunto(s)
Humanos , Acetona , Biomarcadores , Orina , Cromatografía Liquida , Colodión , Electroforesis en Gel de Poliacrilamida , Calor , Proteínas , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem , Orina , Química
7.
Chinese Journal of Biotechnology ; (12): 982-989, 2014.
Artículo en Chino | WPRIM | ID: wpr-279454

RESUMEN

Nitrocellulose membrane based urinary protein preservation method is simple, fast and economic, but its advantage over the traditionally used acetone precipitation method is still unclear. In this work, we prepared urinary proteins by the two methods by LC-MS/MS. Then we used protein spectra counts to assess the reproducibility of the two methods. Proteins identified by the two methods were almost the same in number, spectral count distribution and distribution of coefficients of variation value. In conclusion, nitrocellulose membrane method is generally the same as acetone precipitation method. It can be used for large scale preservation of clinical urine samples.


Asunto(s)
Humanos , Acetona , Cromatografía Liquida , Colodión , Espectrometría de Masas , Proteínas , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem , Orina , Química
8.
The Journal of Advanced Prosthodontics ; : 226-233, 2013.
Artículo en Inglés | WPRIM | ID: wpr-181924

RESUMEN

PURPOSE: This study evaluated the adhesion of 10-MDP containing self-etch and self-adhesive resin cements to dentin with and without the use of etch-and-rinse technique. MATERIALS AND METHODS: Human third molars (N=180) were randomly divided into 6 groups (n=30 per group). Conventional (Panavia F2.0, Kuraray-PAN) and self-adhesive resin cements (Clearfil SA, Kuraray-CSA) were bonded to dentin surfaces either after application of 3-step etch-and-rinse (35% H3PO4 + ED Primer) or two-step self-etch adhesive resin (Clearfil SE Bond). Specimens were subjected to shear bond strength test using the universal testing machine (0.5 mm/min). The failure types were analyzed using a stereomicroscope and quality of hybrid layer was observed under a scanning electron microscope. The data (MPa) were analyzed using two-way ANOVA and Tukey's tests (alpha=.05). RESULTS: Overall, PAN adhesive cement showed significantly higher mean bond strength (12.5 +/- 2.3 - 14.1 +/- 2.4 MPa) than CSA cement (9.3 +/- 1.4 - 13.9 +/- 1.9 MPa) (P<.001). Adhesive failures were more frequent in CSA cement groups when used in conjunction with two-step self-adhesive (68%) or no adhesive at all (66%). Hybrid layer quality was inferior in CSA compared to PAN cement in all conditions. CONCLUSION: In clinical situations where bonding to dentin substrate is crucial, both conventional and self-adhesive resin cements based on 10-MDP can benefit from etch-and-rinse technique to achieve better quality of adhesion in the early clinical period.


Asunto(s)
Humanos , Adhesivos , Compuestos de Aluminio , Compuestos de Calcio , Quimera , Colodión , Dentina , Electrones , Tercer Molar , Cementos de Resina , Compuestos de Azufre
9.
The Journal of Advanced Prosthodontics ; : 241-247, 2013.
Artículo en Inglés | WPRIM | ID: wpr-181922

RESUMEN

PURPOSE: To evaluate the effect of various metal oxides on impact strength (IS), fracture toughness (FT), water sorption (WSP) and solubility (WSL) of heat-cured acrylic resin. MATERIALS AND METHODS: Fifty acrylic resin specimens were fabricated for each test and divided into five groups. Group 1 was the control group and Group 2, 3, 4 and 5 (test groups) included a mixture of 1% TiO2 and 1% ZrO2, 2% Al2O3, 2% TiO2, and 2% ZrO2 by volume, respectively. Rectangular unnotched specimens (50 mm x 6.0 mm x 4.0 mm) were fabricated and droptower impact testing machine was used to determine IS. For FT, compact test specimens were fabricated and tests were done with a universal testing machine with a cross-head speed of 5 mm/min. For WSP and WSL, discshaped specimens were fabricated and tests were performed in accordance to ISO 1567. ANOVA and Kruskal-Wallis tests were used for statistical analyses. RESULTS: IS and FT values were significantly higher and WSP and WSL values were significantly lower in test groups than in control group (P<.05). Group 5 had significantly higher IS and FT values and significantly lower WSP values than other groups (P<.05) and provided 40% and 30% increase in IS and FT, respectively, compared to control group. Significantly lower WSL values were detected for Group 2 and 5 (P<.05). CONCLUSION: Modification of heat-cured acrylic resin with metal oxides, especially with ZrO2, may be useful in preventing denture fractures and undesirable physical changes resulting from oral fluids clinically.


Asunto(s)
Colodión , Bases para Dentadura , Dentaduras , Óxidos , Polímeros , Polimetil Metacrilato , Refuerzo en Psicología , Solubilidad , Agua
10.
The Journal of Advanced Prosthodontics ; : 248-255, 2013.
Artículo en Inglés | WPRIM | ID: wpr-181921

RESUMEN

PURPOSE: This study compared the effect of three intraoral repair systems on the bond strength between composite resin and zirconia core. MATERIALS AND METHODS: Thirty zirconia specimens were divided into three groups according to the repair method: Group I- CoJet(TM) Repair System (3M ESPE) [chairside silica coating with 30 microm SiO2 + silanization + adhesive]; Group II- Ceramic Repair System (Ivoclar Vivadent) [etching with 37% phosphoric acid + Zirconia primer + adhesive]; Group III- Signum Zirconia Bond (Heraus) [Signum Zirconia Bond I + Signum Zirconia Bond II]. Composite resin was polymerized on each conditioned specimen. The shear bond strength was tested using a universal testing machine, and fracture sites were examined with FE-SEM. Surface morphology and wettability after surface treatments were examined additionally. The data of bond strengths were statistically analyzed with one-way ANOVA and Tamhane post hoc test (alpha=.05). RESULTS: Increased surface roughness and the highest wettability value were observed in the CoJet sand treated specimens. The specimens treated with 37% phosphoric acid and Signum Zirconia Bond I did not show any improvement of surface irregularity, and the lowest wettability value were found in 37% phosphoric acid treated specimens. There was no significant difference in the bond strengths between Group I (7.80 +/- 0.76 MPa) and III (8.98 +/- 1.39 MPa). Group II (3.21 +/- 0.78 MPa) showed a significant difference from other groups (P<.05). CONCLUSION: The use of Intraoral silica coating system and the application of Signum Zirconia Bond are effective for increasing the bond strength of composite resin to zirconia.


Asunto(s)
Cerámica , Colodión , Ácidos Fosfóricos , Polímeros , Dióxido de Silicio , Humectabilidad , Circonio
11.
The Journal of Advanced Prosthodontics ; : 278-286, 2013.
Artículo en Inglés | WPRIM | ID: wpr-181917

RESUMEN

PURPOSE: The aim of this study was to determine whether the push-out bond strengths between the radicular dentin and fiber reinforced-composite (FRC) posts with various resin cements decreased or not, according to the coronal, middle or apical level of the root. MATERIALS AND METHODS: FRC posts were cemented with one of five resin cement groups (RelyX Unicem: Uni, Contax with activator & LuxaCore-Dual: LuA, Contax & LuxaCore-Dual: Lu, Panavia F 2.0: PA, Super-Bond C&B: SB) into extracted human mandibular premolars. The roots were sliced into discs at the coronal, middle and apical levels. Push-out bond strength tests were performed with a universal testing machine at a crosshead speed of 0.5 mm/min, and the failure aspect was analyzed. RESULTS: There were no significant differences (P>.05) in the bond strengths of the different resin cements at the coronal level, but there were significant differences in the bond strengths at the middle and apical levels (P.05); all other groups had a significant decrease in bond strength at the middle or apical level (P<.05). The failure aspect was dominantly cohesive at the coronal level of all resin cements (P<.05), whereas it was dominantly adhesive at the apical level. CONCLUSION: All resin cement groups showed decreases in bond strengths at the middle or apical level except LuA and Uni.


Asunto(s)
Humanos , Adhesivos , Diente Premolar , Compuestos de Boro , Colodión , Resinas Compuestas , Cementos Dentales , Dentina , Metacrilatos , Metilmetacrilatos , Cementos de Resina
12.
The Journal of Advanced Prosthodontics ; : 287-295, 2013.
Artículo en Inglés | WPRIM | ID: wpr-181916

RESUMEN

PURPOSE: This study investigated the effect of laser parameters and air-abrasion on the peel strength of silicon-based soft denture liner to different denture resins. MATERIALS AND METHODS: Specimens (N=180) were prepared out of three different denture base resins (Rodex, cross-linked denture base acrylic resin; Paladent, heat-cured acrylic resin; Deflex, Polyamide resin) (75 mm x 25 mm x 3 mm). A silicon-based soft denture liner (Molloplast B) was applied to the denture resins after the following conditioning methods: a) Air-abrasion (50 microm), b) Er,Cr:YSGG laser (Waterlase MD Turbo, Biolase Technology) at 2 W-20 Hz, c) Er,Cr:YSGG laser at 2 W-30 Hz, d) Er,Cr:YSGG laser at 3 W-20 Hz, e) Er,Cr:YSGG laser at 3 W-30 Hz. Non-conditioned group acted as the control group. Peel test was performed in a universal testing machine. Failure modes were evaluated visually. Data were analyzed using two-way ANOVA and Tukey's test (alpha=.05). RESULTS: Denture liner tested showed increased peel strength after laser treatment with different parameters (3.9+/-0.4 - 5.58+/-0.6 MPa) compared to the control (3.64+/-0.5 - 4.58+/-0.5 MPa) and air-abraded groups (3.1+/-0.6 - 4.46+/-0.3 MPa), but the results were not statistically significant except for Paladent, with the pretreatment of Er,Cr:YSGG laser at 3 W-20 Hz. Polyamide resin after air-abrasion showed significantly lower peel strength than those of other groups (3.1+/-0.6 MPa). CONCLUSION: Heat-cured acrylic resin, PMMA, may benefit from Er,Cr:YSGG laser treatment at 3 W-20 Hz irradiation. Air-abrasion of polyamide resins should be avoided not to impair their peel bond strengths to silicon-based soft denture liners.


Asunto(s)
Colodión , Bases para Dentadura , Alineadores Dentales , Dentaduras , Nylons , Polimetil Metacrilato
13.
Annals of Dermatology ; : 483-488, 2013.
Artículo en Inglés | WPRIM | ID: wpr-123642

RESUMEN

Neu-Laxova syndrome is a rare, lethal, autosomal recessive disorder characterized by intrauterine growth retardation, central nervous system anomalies, skin findings, such as ichthyosis, edema, collodion baby and harlequin fetus, facial dysmorphic features, limb anomalies and genital hypoplasia. Although it is generally a lethal condition, cases of such patients who lived beyond 6 months and 10 months of age have been reported. Here, we describe an 8-year-old boy who was born with collodion membrane, facial dysmorphic features, limb anomalies, genital hypoplasia and pachygyria. He had no major health problems over the course of 8 years of follow-up, except for mild mental/motor retardation, ichthyosis, facial dysmorphic features and limb anomalies. Based on these features, we suggest that because Neu-Laxova syndrome represents a heterogeneous phenotype, our case may be a milder variant of this syndrome or a new genetic entity.


Asunto(s)
Niño , Humanos , Masculino , Anomalías Múltiples , Encefalopatías , Sistema Nervioso Central , Colodión , Edema , Extremidades , Retardo del Crecimiento Fetal , Estudios de Seguimiento , Ictiosis , Ictiosis Lamelar , Deformidades Congénitas de las Extremidades , Lisencefalia , Membranas , Microcefalia , Fenotipo , Piel
14.
The Korean Journal of Orthodontics ; : 186-192, 2013.
Artículo en Inglés | WPRIM | ID: wpr-121612

RESUMEN

OBJECTIVE: To analyze the fatigue resistance, debonding force, and failure type of fiber-reinforced composite, polyethylene ribbon-reinforced, and braided stainless steel wire lingual retainers in vitro. METHODS: Roots of human mandibular central incisors were covered with silicone, mimicking the periodontal ligament, and embedded in polymethylmethacrylate. The specimens (N = 50), with two teeth each, were randomly divided into five groups (n = 10/group) according to the retainer materials: (1) Interlig (E-glass), (2) everStick Ortho (E-glass), (3) DentaPreg Splint (S2-glass), (4) Ribbond (polyethylene), and (5) Quad Cat wire (stainless steel). After the recommended adhesive procedures, the retainers were bonded to the teeth by using flowable composite resin (Tetric Flow). The teeth were subjected to 10,00,000 cyclic loads (8 Hz, 3 - 100 N, 45degrees angle, under 37 +/- 3degrees C water) at their incisoproximal contact, and debonding forces were measured with a universal testing machine (1 mm/min crosshead speed). Failure sites were examined under a stereomicroscope (x40 magnification). Data were analyzed by one-way analysis of variance. RESULTS: All the specimens survived the cyclic loading. Their mean debonding forces were not significantly different (p > 0.05). The DentaPreg Splint group (80%) showed the highest incidence of complete adhesive debonding, followed by the Interlig group (60%). The everStick Ortho group (80%) presented predominantly partial adhesive debonding. The Quad Cat wire group (50%) presented overlying composite detachment. CONCLUSIONS: Cyclic loading did not cause debonding. The retainers presented similar debonding forces but different failure types. Braided stainless steel wire retainers presented the most repairable failure type.


Asunto(s)
Animales , Gatos , Humanos , Adenina , Adhesivos , Carbamatos , Colodión , Resinas Compuestas , Desoxicitidina , Combinación de Medicamentos , Fatiga , Incidencia , Incisivo , Organofosfonatos , Ligamento Periodontal , Polietileno , Polietilenos , Polimetil Metacrilato , Quinolonas , Recurrencia , Retención en Psicología , Siliconas , Férulas (Fijadores) , Acero Inoxidable , Tiazoles , Diente , Combinación Elvitegravir, Cobicistat, Emtricitabina y Fumarato de Tenofovir Disoproxil
15.
The Korean Journal of Orthodontics ; : 96-100, 2013.
Artículo en Inglés | WPRIM | ID: wpr-143928

RESUMEN

OBJECTIVE: To evaluate the effects of contamination by either blood or a hemostatic agent on the shear bond strength (SBS) of orthodontic buttons. METHODS: We used 45 freshly extracted, non-carious, impacted third molars that were divided into 3 groups of 15. Each tooth was etched with 37% phosphoric acid gel for 30 s. Human blood or the blood stopper agent was applied to the tooth surface in groups I and II, respectively. Group III teeth were untreated (controls). Orthodontic buttons were bonded to the teeth using light-curing composite resin. After bonding, the SBS of the button was determined using a Universal testing machine. Any adhesive remaining after debonding was assessed and scored according to the modified adhesive remnant index (ARI). ANOVA with post-hoc Tukey's test was used to determine significant differences in SBS and Fisher's exact test, to determine significant differences in ARI scores among groups. RESULTS: ANOVA indicated a significant difference between groups (p < 0.001). The highest SBS values were measured in group III (10.73 +/- 0.96 MPa). The SBS values for teeth in groups I and II were significantly lower than that of group III (p < 0.001). The lowest SBS values were observed in group I teeth (4.17 +/- 1.11 MPa) (p < 0.001). CONCLUSIONS: Contamination of tooth surfaces with either blood or hemostatic agent significantly decreased the SBS of orthodontic buttons. When the contamination risk is high, it is recommended to use the blood stopper agent when bonding orthodontic buttons on impacted teeth.


Asunto(s)
Humanos , Adhesivos , Colodión , Tercer Molar , Ácidos Fosfóricos , Diente , Diente Impactado
16.
The Korean Journal of Orthodontics ; : 96-100, 2013.
Artículo en Inglés | WPRIM | ID: wpr-143921

RESUMEN

OBJECTIVE: To evaluate the effects of contamination by either blood or a hemostatic agent on the shear bond strength (SBS) of orthodontic buttons. METHODS: We used 45 freshly extracted, non-carious, impacted third molars that were divided into 3 groups of 15. Each tooth was etched with 37% phosphoric acid gel for 30 s. Human blood or the blood stopper agent was applied to the tooth surface in groups I and II, respectively. Group III teeth were untreated (controls). Orthodontic buttons were bonded to the teeth using light-curing composite resin. After bonding, the SBS of the button was determined using a Universal testing machine. Any adhesive remaining after debonding was assessed and scored according to the modified adhesive remnant index (ARI). ANOVA with post-hoc Tukey's test was used to determine significant differences in SBS and Fisher's exact test, to determine significant differences in ARI scores among groups. RESULTS: ANOVA indicated a significant difference between groups (p < 0.001). The highest SBS values were measured in group III (10.73 +/- 0.96 MPa). The SBS values for teeth in groups I and II were significantly lower than that of group III (p < 0.001). The lowest SBS values were observed in group I teeth (4.17 +/- 1.11 MPa) (p < 0.001). CONCLUSIONS: Contamination of tooth surfaces with either blood or hemostatic agent significantly decreased the SBS of orthodontic buttons. When the contamination risk is high, it is recommended to use the blood stopper agent when bonding orthodontic buttons on impacted teeth.


Asunto(s)
Humanos , Adhesivos , Colodión , Tercer Molar , Ácidos Fosfóricos , Diente , Diente Impactado
17.
The Journal of Korean Academy of Prosthodontics ; : 99-106, 2013.
Artículo en Coreano | WPRIM | ID: wpr-56592

RESUMEN

PURPOSE: The aim of this research was to establish the effect and variation in differing convergence angle and length of abutment on the retention of full veneer casted gold crown. MATERIALS AND METHODS: Two different length,5 mm and 10 mm in height with convergence angles of 5, 10, 15 and 25 degrees crowns were fabricated. Cementation was done using cements; zinc phosphate cement (Fleck's zinc phosphate cement), resin-modified glass ionomer cement (Vitremer) and resin cement (Panavia 21). These were tested for tensile force at the point of separation by using Instron Universal Testing Machine. Statistical analysis was done by SAS 6.04 package. RESULTS: In all cements the mean retention decreased with significant difference on increase of convergence angle (P<.05). Increase in every 5 degree-convergence angel the retention rate decreased with resin-modified glass ionomer cement of 15.9% and resin cement of 14.8%. With zinc phosphate cement, there was largest decreasing rate of mean retention of 25.5% between convergence angles from 5 degree to 10 degree. When the crown length increased from 5 mm to 10 mm, the retention increased with the significant difference in the same convergence angle and in all types of cement used (P<.05). CONCLUSION: The retention was strongly dependent on geometric factors of abutment. Much care is required in choosing cements for an optimal retention in abutments with different convergence angles and crown lengths.


Asunto(s)
Resinas Acrílicas , Cementación , Colodión , Coronas , Cementos Dentales , Cementos de Ionómero Vítreo , Fenotiazinas , Fosfatos , Cementos de Resina , Retención en Psicología , Dióxido de Silicio , Zinc , Compuestos de Zinc , Cemento de Fosfato de Zinc
18.
The Journal of Advanced Prosthodontics ; : 16-20, 2013.
Artículo en Inglés | WPRIM | ID: wpr-13013

RESUMEN

PURPOSE: To assess the retention of glass fiber post cemented with self-adhesive resin cement into optimum and over-prepared root canals following obturation in the presence of either eugenol (EB) or calcium hydroxide (CB)-based sealers. MATERIALS AND METHODS: Roots of extracted premolars were endodontically-treated in 5 groups (n = 10). Roots of Group 1 (control) were left with no obturation and then optimally prepared to receive endodontic dowels. Other root canals were obturated with gutta-percha in the presence of either eugenol-based (Groups 2 and 4) or calcium hydroxide-based (Groups 3 and 5) sealer. Dowel spaces were prepared with optimal diameter in Groups 2 and 3, one size larger in Groups 4 and 5. Standardized fiber posts were luted to the prepared spaces using self-adhesive resin cement and itsretention was then tested on an universal testing machine. Both one-way ANOVA and Tukey's HSD comparisons (alpha=0.05) were used to identifythe significance of inter-group retention differences. Scanning electron microscopy (SEM) of both optimally and over-prepared dowel spaces was also considered to figure the nature of their interior out. RESULTS: The post retention was significantly higher to the non-obturated, optimally-prepared dowel spaces of Group 1 compared to the obturated, optimally-prepared ones of Groups 2 and 3. For each dowel space diameter, root canals obturated using CB of Groups 3 and 5 showed significantly higher dowel retention compared to those obturated using EB of Groups 2 and 4. Post retention to the over-prepared dowel spaces of Groups 4 and 5 was significantly higher than that recorded for the optimally-prepared ones of Groups 1-3. SEM images revealed traces of endodontic sealer and gutta-percha on the walls of the optimally-prepared dowel spaces. CONCLUSION: Despite the adverse effect of endodontic sealers on the retention of fiber posts, the over-preparation of dowel spaces helps to improve the retention.


Asunto(s)
Diente Premolar , Calcio , Hidróxido de Calcio , Colodión , Cavidad Pulpar , Eugenol , Vidrio , Gutapercha , Hidróxidos , Microscopía Electrónica de Rastreo , Cementos de Resina , Retención en Psicología
19.
The Journal of Advanced Prosthodontics ; : 36-43, 2013.
Artículo en Inglés | WPRIM | ID: wpr-13010

RESUMEN

PURPOSE: The objective of this study was to compare the fracture toughness (KIc) obtained from the single edge V-notched beam (SEVNB) and the fractographic analysis (FTA) of a glass-infiltrated and a zirconia ceramic. MATERIALS AND METHODS: For each material, ten bar-shaped specimens were prepared for the SEVNB method (3 mm x 4 mm x 25 mm) and the FTA method (2 mm x 4 mm x 25 mm). The starter V-notch was prepared as the fracture initiating flaw for the SEVNB method. A Vickers indentation load of 49 N was used to create a controlled surface flaw on each FTA specimen. All specimens were loaded to fracture using a universal testing machine at a crosshead speed of 0.5-1 mm/min. The independent-samples t-test was used for the statistical analysis of the KIc values at alpha=0.05. RESULTS: The mean KIc of zirconia ceramic obtained from SEVNB method (5.4 +/- 1.6 MPa.m1/2) was comparable to that obtained from FTA method (6.3 +/- 1.6 MPa.m1/2). The mean KIc of glass-infiltrated ceramic obtained from SEVNB method (4.1 +/- 0.6 MPa.m1/2) was significantly lower than that obtained from FTA method (5.1 +/- 0.7 MPa.m1/2). CONCLUSION: The mean KIc of the glass-infiltrated and zirconia ceramics obtained from the SEVNB method were lower than those obtained from FTA method even they were not significantly different for the zirconia material. The differences in the KIc values could be a result of the differences in the characteristics of fracture initiating flaws of these two methods.


Asunto(s)
Cerámica , Colodión , Circonio
20.
Korean Journal of Medical History ; : 1-40, 2013.
Artículo en Coreano | WPRIM | ID: wpr-12566

RESUMEN

In this study, I am planning to analyze the contents of Simple formula in Treasured Mirror of Eastern Medicine (TM), and then find out the historical implication of medical science. Simple formula is a prescription that is consisted of a single or three to four kinds of medicines, and this does not follow typical control principles such as 'sovereign, minister, assistant and courier'. While simple formulas are often built after major formulas, TM placed simple formulas to an end of each classified item. It is difficult to find a similar compilation style as that of Simple formula among similar volumes of medical books during the same period of TM. Thus, it can be assumed that TM included simple formulas for special purposes or reasons which are deemed as an important factor in stipulating the features of TM. The tradition of Simple formula, using medicinal herbs which can be easily acquired and trying to make an effect with a small number of herbs, had existed before Goryeo Dynasty. Introduced by Emergency Prescriptions from the Countryside and Samhwaja's Formulary from the Countryside, the tradition of Simple formula is succeeded by Compendium of Prescriptions from the Countryside, and after a while, it is synthetically arranged and recognized through Simple formula of TM. By analyzing simple formulas of TM, I could find out the followings. First, in simple formulas of TM, in which the components are the number of medicinal herbs, the name of prescription, and their application, should be understood as a simply consisted prescription rather than single medicine formulas. Second, simple formulas of TM are 2,001 in total, and are organized in most items. Third, although simple formulas cite a number of formulary, it shows a high degree of dependence to Classified Emergency Materia Medica. This shows that simple formulas that are structured to use medicine according to symptoms based on the effect of each medicinal herb, without understanding or dialectic process of syndrome differentiation. Fourth, while the part of medicinal herbs, Decoction section, focuses on listing the information of each medicinal herb, simple formulas introduce effect, dose, volume and even a mix with other medicinal herbs and an application of them. Therefore, a simple formula evaluates single medicinal herb as a sort of prescription. Fifth, more than half of 33 kinds of medicinal herbs, which are used more than 11 times in simple formulas of TM, are easy to get around the village, and their Korean names of Materia Medica from the Countryside are possible to be seen in Decoction section. However, the fact that Materia Medica from China such as Coptics chinensis and Realgar is included in simple formulas means that they are not limited to Materia Medica from the Countryside, and some of Materia Medica from China were not difficult to be procured in the time of publication of TM. Specific purpose of publishing simple formulas is not written separately. However, through the king's command of King Seonjo (1552-1608) in introduction, the active containing of folk prescriptions, and the emphasis of medicinal herb's volume using simple formulas, it is assumed that the Chosun government at that time tried to provide friendly and practical medical information with simple formulas, to collect and formulate private medical experiences in order to expand their extension of medical information, and to maximize the effect of treatment. The compilation system like TM was highly regarded but was also the target of criticism. In particular, King Jeongjo (1752-1800) criticized the complicatedness of TM and deleted information related to simple formulas through government compilation medical texts such as Explanation of Subtleties for the People's Longevity, New Edition on Universal Relife. However, simple formulas which were not composed of many medicinal herbs could be useful way for treating people who did not have professional medical knowledge and did not have a large range of herbs. In actuality, Secret Works of Universal Benefit, the representative compilation of civil medicinal text which was published after TM included information related to simple formulas, and in Records for rural life of Chosun gentlemen, the framework of simple formulas of TM was maintained and is filled with a vast amount of information. Furthermore, cases of utilizing simple formulas are included in the U-Jam's miscellaneous writings which is a clinical record. In Simple formulas of TM, private medical experiences at the time of Chosun are written first, then recognized by the experts, and finally returned to the public. Although the purpose and the target of these simple formulas publication are not clearly known, it is easy found, does not require any advanced medical knowledge, and above all, the people must have welcomed to the supply of economic simple formulas. Therefore, simple formulas show an aspect of TM, as a medical book for public.


Asunto(s)
Arsenicales , Butanonas , China , Colodión , Inhibidores de la Ciclooxigenasa 2 , Recubrimiento de la Cavidad Dental , Urgencias Médicas , Hipogonadismo , Longevidad , Materia Medica , Enfermedades Mitocondriales , Oftalmoplejía , Plantas Medicinales , Prescripciones , Publicaciones , Sulfuros
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