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1.
Chin Med J (Engl) ; 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39090777

RESUMEN

BACKGROUND: Neoadjuvant therapy enhances the possibility of achieving radical resection and improves the prognosis for locally advanced gastric cancer (GC). However, there is a lack of evidence regarding the optimal extent of resection for locally advanced proximal GC after neoadjuvant therapy. METHODS: In this study, 330 patients underwent resection in Peking University Cancer Hospital, with curative intent after neoadjuvant therapy for histologically confirmed proximal GC from January 2009 to December 2022. Among them, 45 patients underwent proximal gastrectomy (PG), while 285 underwent total gastrectomy (TG). RESULTS: In this study, 45 patients underwent proximal gastrectomy (PG), while 285 underwent total gastrectomy (TG). After propensity-score matching, 110 patients (71 TG and 39 PG) were included in the analysis. No significant differences between PG and TG regarding short-term outcomes and long-term prognosis were found. Specifically, PG demonstrated comparable overall survival to TG (P = 0.47). Subgroup analysis revealed that although not statistically significant, PG showed a potential advantage over TG in overall survival for patients with tumor-long diameters less than 4 cm (P = 0.31). However, for those with a long diameter larger than 4 cm, TG had a better survival probability (P = 0.81). No substantial differences were observed in baseline characteristics, surgical safety, postoperative recovery, and postoperative complications. CONCLUSION: For locally advanced proximal GC with objective response to neoadjuvant therapy (long diameter <4 cm), PG is an alternative surgical procedure. Further research and prospective studies are warranted to validate these findings and guide clinical decision-making.

2.
Front Surg ; 11: 1390876, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38605734

RESUMEN

Background: This study aimed to compare the clinical outcomes and patient benefits of uncut Roux-en-Y (URY) anastomosis and Billroth-II with Braun (BB) anastomosis after distal gastrectomy. Methods: We retrospectively reviewed the data of patients who underwent URY or BB anastomosis after distal gastrectomy between March 2015 and December 2017. Clinical characteristics, survival data, postoperative recovery data, and long-term outcomes were recorded and compared between the two groups. Results: A total of 231 patients were included, with 167 in the URY group and 64 in the BB group. Kaplan-Meier curves for overall survival showed no differences after propensity score matching (p = 0.488). Long-term postoperative quality of life evaluation also showed no significant differences. Compared to the BB group, patients in the URY group had a significantly shorter time to start a liquid diet after propensity score matching (67.6 h vs. 46.5 h, p = 0.003), and a lower occurrence of bile reflux on follow-up gastroscopy (p < 0.001). Conclusion: The URY anastomosis appears to be a feasible method for digestive tract reconstruction after distal gastrectomy, resulting in less bile reflux and better postoperative recovery. However, there is no significant difference between URY and BB anastomosis in terms of overall survival and long-term quality of life.

3.
Langmuir ; 38(50): 15817-15826, 2022 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-36490371

RESUMEN

The effectiveness of photocatalytic and Fenton reactions in the synergistic treatment of water pollution problems has become indisputable. In this paper, nitrogen-doped TiO2 was selected as the catalyst for the photocatalytic reaction and manganese-substituted phosphomolybdic acid was used as the Fenton reagent, the two of which were combined together by acid impregnation to construct a binary photocatalysis-Fenton composite catalyst. The degradation experiments of the composite catalyst on RhB indicated that under UV-vis irradiation, the composite catalyst could degrade RhB almost completely within 8 min, and the degradation rate was 19.7 times higher than that of N-TiO2, exhibiting a superior degradation ability. Simultaneously, a series of characterization methods were employed to analyze the structure, morphology, and optical properties of the catalysts. The results demonstrated that the nitrogen doping not only expanded the photo response range of TiO2 but reduced the work function of TiO2, which facilitated the transfer of electrons to the loaded Mn-HPMo side and further promoted the electron-hole separation efficiency. In addition, the introduction of Mn-HPMo provided three pathways for the activation of hydrogen peroxide, which enhanced the degradation activity. This study provides novel insights into the construction of binary and efficient catalysts with multiple hydroxyl radical generation pathways.


Asunto(s)
Manganeso , Nitrógeno , Nitrógeno/química , Catálisis
4.
Chem Commun (Camb) ; 56(53): 7337-7340, 2020 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-32483580

RESUMEN

Cu oxide-modified CeO2 (CuOx-CeO2) with 2 wt% Cu loading amount was the most effective and reusable heterogeneous catalyst for selective one-pot imine synthesis from methylarenes and anilines via direct oxidation of the sp3 C-H bond in the methylarenes with atmospheric air (0.1 MPa) as an oxidant.

5.
ACS Macro Lett ; 9(8): 1178-1183, 2020 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-35653209

RESUMEN

Carvone, a naturally abundant chiral cyclic α,ß-unsaturated carbonyl compound, was chemically transformed into cyclic exo-methylene conjugated dienes. The exo-methylene group had high reactivity in cationic polymerization and was efficiently polymerized in a controlled manner via regioselective 1,4-conjugated additions using initiating systems effective for living cationic polymerization of vinyl ethers. The obtained polymers with 1,3-cyclohexenyl units and tetra-substituted olefins in the main chain showed high glass transition temperatures over 110 °C. The chiral monomer underwent stereospecific polymerization to result in polymers with low solubility and weak packing of the rigid main chain in the lamellar layers. The racemic mixture resulted in soluble amorphous polymers, which were subsequently hydrogenated into cycloolefin polymers with enhanced thermal properties.

6.
J Pathol ; 243(2): 165-175, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28671728

RESUMEN

Gastro-oesophageal junction (GEJ) carcinoma and distal gastric cancer (GC) have distinct epidemiology and clinical features and their relationship is uncertain. Synchronous multiple gastric cancers located mostly at proximal and distal sites provide rare specimens for investigating the comprehensive genomic relationships among these cancers in the context of identical genetic circumstances. Formalin-fixed, paraffin-embedded (FFPE) samples from 12 patients with synchronous GEJ carcinoma and distal GC were collected in this study. Whole-exome sequencing (WES) was performed using normal tissues as a control. Mutational profiling, clonality analysis, a detailed clinico-pathological review, determination of MSI status, EBER in situ hybridization (ISH), and programmed cell death 1 (PD-1)/programmed death-ligand 1 (PD-L1) immunohistochemical staining were performed. Twenty-three of the 24 samples were microsatellite-stable (MSS). Subclonal analysis revealed that nine pairs of GEJ and distal GC tumours in neoadjuvant chemotherapy naïve patients developed independently from different origins. Two patients who received neoadjuvant chemotherapy shared clonal origins with highly similar somatic alterations. The remaining one patient who shared a rare mutation died within 6.2 months at the N3 stage. However, the enriched pathway identified from the overall mutation spectra in distal GC and GEJ carcinoma showed the close relationship of these cancers. Thus, although these cancers may have similar characteristics, histopathological and genetic profiling from single tumour specimens may still underestimate the mutational burden and somatic heterogeneity of multiple GCs. In addition, this series of cases also showed a PD-L1 expression rate of 58.3% and 66.7% in distal GC and GEJ carcinoma, respectively, with all the cases expressing PD-1. This result suggests the potential benefit of immunotherapeutic treatments. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Asunto(s)
Neoplasias Esofágicas/genética , Unión Esofagogástrica , Neoplasias Gástricas/genética , Anciano , Células Clonales/fisiología , Análisis Mutacional de ADN/métodos , Neoplasias Esofágicas/patología , Exoma/genética , Femenino , Humanos , Masculino , Repeticiones de Microsatélite/genética , Persona de Mediana Edad , Mutación/genética , Proteínas de Neoplasias/genética , Neoplasias Gástricas/patología , Carga Tumoral
7.
J Nanosci Nanotechnol ; 17(4): 2791-795, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29667808

RESUMEN

Nano/submicro vanadium dioxide rods in monoclinic phase (VO2 (M)) were synthesized through hydrothermal reaction combined with subsequent calcinations. The morphology and structure of samples were characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The average diameter of VO2 (M) dioxide rods from 210 nm to 1 µm were successfully controlled by adjusting the synthesis conditions including the concentration of Vanadium pentoxide (V2O5) solution and the molar ratio of V2O5 and oxalic acid. Our results reveal that the concentration of V2O5 is the key factor to determine the diameter of VO2 (M) rods, while higher molar ratio favors formation of VO2 rods with narrow diameter distributions. The growth mechanism of vanadium dioxide rods was discussed.

8.
Gastric Cancer ; 19(1): 116-27, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25618371

RESUMEN

BACKGROUND: Gastric cancer (GC) is an aggressive malignancy whose mechanisms of development and progression are poorly understood. The identification of prognosis-related genomic loci and genes may suffer from the relatively small case numbers and a lack of systematic validation in previous studies. METHODS: Array-based comparative genomic hybridization (aCGH) coupled with patient clinical information was applied to identify prognosis-related loci and genes with high-frequency recurrent gains in 129 GC patients. The candidate loci and genes were then validated using an independent cohort of 384 patients through branched DNA signal amplification analysis (QuantiGene assays). RESULTS: In the 129 patients, a copy number gain of three chromosome regions-namely, 8q22 (including ESRP1 and CCNE2), 8q24 (including MYC and TNFRSF11B), and 20q11-q13 (including SRC, MMP9, and CSE1L)--conferred poor survival for patients. In addition, the correlation between the branched DNA signal amplification analysis results and the aCGH results was analyzed in 73 of these 129 patients, and MYC, TNFRSF11B, ESRP1, CSE1L, and MMP9 were found to be well correlated. Further validation using an independent cohort (n = 384) verified that only MYC and TNFRSF11B within 8q24 are related to survival. Patients with gains in both MYC and TNFRSF11B had poorer survival than those with no gains, particularly those with noncardia GC. Gains in both of these genes were also a significant independent prognostic indicator. CONCLUSIONS: Our results revealed that copy number gains in MYC and TNFRSF11B located at 8q24 are associated with survival in GC, particularly noncardia GC.


Asunto(s)
Cromosomas Humanos Par 8 , Genes myc , Osteoprotegerina/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Hibridación Genómica Comparativa/métodos , Femenino , Amplificación de Genes , Dosificación de Gen , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Neoplasias Gástricas/patología , Análisis de Supervivencia
9.
Zhonghua Wei Chang Wai Ke Za Zhi ; 16(2): 179-82, 2013 Feb.
Artículo en Chino | MEDLINE | ID: mdl-23446483

RESUMEN

OBJECTIVE: To explore the expression of CCAAT/enhancer binding protein beta (CEBPB) in gastric carcinoma tissues and its association with clinicopathological features and prognosis. METHODS: CEBPB protein expression level was detected by immunohistochemistry method in resected gastric carcinomas and adjacent gastric mucosa tissues (n=81), and its association with clinicopathological features and prognosis was analyzed. RESULTS: The immunohistochemical staining of CEBPB was predominantly in the nucleus with some cytoplasmic staining. As a result, 16% (13/81) of the gastric carcinomas were stained positively, whereas there was hardly positive expression in adjacent gastric mucosa tissues. There was a significant association between the expression of CEBPB and distant metastasis on univariate analysis (P<0.05). The median survival time in patients with positive CEBPB expression was significantly lower than those with negative CEBPB expression (19.4 months vs. 45.2 months, P=0.024). Multivariable analysis showed that CEBPB was independently associated with prognosis (HR=2.544, 95%CI:1.154-5.610, P=0.021). CONCLUSION: Up-regulation of CEBPB suggests poor prognosis in patients with gastric cancer.


Asunto(s)
Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Neoplasias Gástricas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patología , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Neoplasias Gástricas/patología
10.
Chin J Cancer Res ; 25(1): 79-89, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23372345

RESUMEN

OBJECTIVE: To investigate Leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5) expressions in gastric cancer and to evaluate its clinical significance. METHODS: LGR5 expression was assessed by immunohistochemistry in 257 gastric cancer patients after surgery. The relationships between LGR5 expression and clinicopathological features and patients prognosis were statistically analyzed. RESULTS: The expression of LGR5 was significantly higher in gastric cancers as a cancer stem cell marker than in adjacent normal tissues (P<0.001), and more frequently in patients with intestinal type, well-moderate differentiation and stage I and II (P<0.05). Although we found gastric cancer patients with LGR5 positive expression had a poorer prognosis, it didn't meet statistical significance (P>0.05). LGR5 negative expression was significantly related to the favorable overall survival in stage I and II gastric cancer patients (P<0.05). Furthermore, patients with high LGR5 expression tended to be more likely to get progression and have poorer progress-free survival (P<0.05). Multivariate Cox regression analysis revealed that LGR5 expression was an independent factor of overall survival for the patients with stage I and II gastric cancer (P<0.05). CONCLUSIONS: Our results show that LGR5 may play an important role in tumorigenesis and progression and would be a powerful marker to predict the prognosis of patients with stage I and II gastric cancer.

11.
BMC Cancer ; 12: 316, 2012 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-22838504

RESUMEN

BACKGROUND: S100A9 was originally discovered as a factor secreted by inflammatory cells. Recently, S100A9 was found to be associated with several human malignancies. The purpose of this study is to investigate S100A9 expression in gastric cancer and explore its role in cancer progression. METHODS: S100A9 expression in gastric tissue samples from 177 gastric cancer patients was assessed by immunohistochemistry. The expression of its dimerization partner S100A8 and the S100A8/A9 heterodimer were also assessed by the same method. The effect of exogenous S100A9 on motility of gastric cancer cells AGS and BGC-823 was then investigated. RESULTS: S100A9 was specifically expressed by inflammatory cells such as macrophages and neutrophils in human gastric cancer and gastritis tissues. Statistical analysis showed that a high S100A9 cell count (> = 200) per 200x magnification microscopic field in cancer tissues was predictive of early stage gastric cancer. High S100A9-positive cell count was negatively correlated with lymph node metastasis (P = 0.009) and tumor invasion (P = 0.011). S100A9 was identified as an independent prognostic predictor of overall survival of patients with gastric cancer (P = 0.04). Patients with high S100A9 cell count were with favorable prognosis (P = 0.021). Further investigation found that S100A8 distribution in human gastric cancer tissues was similar to S100A9. However, the number of S100A8-positive cells did not positively correlate with patient survival. The inflammatory cells infiltrating cancer were S100A8/A9 negative, while those in gastritis were positive. Furthermore, exogenous S100A9 protein inhibited migration and invasion of gastric cancer cells. CONCLUSIONS: Our results suggested S100A9-positive inflammatory cells in gastric cancer tissues are associated with early stage of gastric cancer and good prognosis.


Asunto(s)
Calgranulina B/inmunología , Neoplasias Gástricas/inmunología , Neoplasias Gástricas/patología , Adulto , Anciano , Anciano de 80 o más Años , Calgranulina A/inmunología , Calgranulina A/metabolismo , Calgranulina B/genética , Calgranulina B/farmacología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Femenino , Humanos , Inflamación/inmunología , Macrófagos/inmunología , Macrófagos/metabolismo , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neutrófilos/inmunología , Neutrófilos/metabolismo , Pronóstico , Multimerización de Proteína , Neoplasias Gástricas/genética , Neoplasias Gástricas/mortalidad
12.
J Surg Oncol ; 106(7): 880-6, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22585737

RESUMEN

BACKGROUND AND OBJECTIVES: Protein tyrosine kinase 7 (PTK7) plays important functions in several cancer types but its expression in gastric cancer remains unknown. This study was designed to investigate PTK7 expression in gastric cancer. METHODS: PTK7 expression was assessed by immunohistochemistry in 201 gastric cancer patients. The relationship between PTK7 expression and clinicopathological features and patients prognosis were statistically analyzed. RESULTS: PTK7 expression was detected in 56.72% (114 of 201) of gastric cancer patients. The immunostaining was predominantly localized in the cytoplasm. The statistical analyses showed that PTK7 expression was more frequently detected in patients with well-differentiated tumors (P = 0.001). Furthermore, PTK7 expression was significantly related to the favorable overall survival (OS; P = 0.012) and disease-free survival (DFS; P = 0.009). Multivariate Cox regression analyses revealed that PTK7 expression was an independent prognostic factor for both favorable OS (P = 0.028) and DFS (P = 0.012). CONCLUSION: Our findings demonstrate that PTK7 can serve as a novel prognostic biomarker for gastric cancer patients.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Moléculas de Adhesión Celular/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/mortalidad , Anciano , Estudios de Casos y Controles , Estudios de Cohortes , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Estadificación de Neoplasias , Pronóstico , Neoplasias Gástricas/patología , Tasa de Supervivencia
13.
Zhonghua Wei Chang Wai Ke Za Zhi ; 15(2): 161-4, 2012 Feb.
Artículo en Chino | MEDLINE | ID: mdl-22368025

RESUMEN

OBJECTIVE: To investigate the clinical value of tumor markers CEA, CA19-9, CA72-4 and CA242 in the diagnosis and prognosis of patients with gastric cancer. METHODS: One hundred and sixty gastric cancer patients who had received treatment from 2002 to 2007 at the Beijing Cancer Hospital were retrospectively analyzed. Blood samples were taken from patients upon admission to the hospital, and CEA, CA19-9, CA72-4, CA242 levels were detected. Statistical analysis was performed to identify the clinical value of these tumor markers in diagnosis and prognosis. RESULTS: On initial diagnosis, the positive rates of CEA, CA19-9, CA72-4 and CA242 were 37.7%, 26.7%, 37.6% and 21.3%, respectively, and the positive rate of combined detection was 62.9%. CEA was more frequently positive in patients with lymph node metastasis (P=0.029); CA72-4 was more frequently positive in patients with vascular involvement and advanced stage (P=0.039, P=0.011). Multivaraite analysis showed that CA72-4 was an independent prognostic factor (P=0.012). Patients with positive CA72-4 carried a 2.147-fold increased risk of death than those with negative CA72-4. Kaplan-Meier analysis showed that patients with positive CA19-9 or positive CA72-4 had worse survival than those with negative CA19-9 or CA72-4 (P=0.006, P=0.002). CONCLUSIONS: Tumor markers including CEA, CA19-9, CA72-4 and CA242 have clinical significance and prognostic value in patients with gastric cancer. Combined detection of four tumor markers can increase the positive rate. CA72-4 is an independent prognostic factor. CA19-9 and CA72-4 are associated with the prognosis of patients with gastric cancer.


Asunto(s)
Biomarcadores de Tumor/sangre , Neoplasias Gástricas/diagnóstico , Antígenos de Carbohidratos Asociados a Tumores/sangre , Antígeno CA-19-9/sangre , Antígeno Carcinoembrionario/sangre , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Neoplasias Gástricas/sangre , Neoplasias Gástricas/patología
14.
J Phys Chem B ; 114(29): 9429-34, 2010 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-20604559

RESUMEN

Bulk quantities of nitrogen-rich graphitic carbon nitride are synthesized via a facile reactive pyrolysis process with a mixture of melamine and cyanuric chloride as the molecular precursors. Scanning electron microscopy and transmission electron microscopy studies show that micrometer-sized hollow vessels with high aspect ratios have been successfully elaborated without the designed addition of any catalyst or template. The composition of the prepared carbon nitride determined by combustion method is C(3)N(4.91)H(1.00)O(0.22), with the N/C ratio to be 1.64, indicating a high nitrogen content. X-ray diffraction pattern reveals the regular stacking of graphene CN(x) monolayers along the (002) direction with the presence of turbostratic ordering of C and N atoms in the a-b basal planes. X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy investigations provide further evidence for graphite-like sp(2)-bonded building blocks based on both triazine and heptazine ring units bridged by 3-fold coordinated nitrogen atoms. The optical properties of the sample are investigated by UV-vis absorption and photoluminescence spectroscopy, which show features characteristic of pi-pi* and n-pi* electronic transitions involving lone pairs of nitrogen atoms. Thermogravimetric analysis curves of the synthesized graphitic carbon nitride hollow vessels show typical weight loss steps related to the volatilization of triazine and heptazine structural units.

15.
Dent Mater J ; 29(4): 374-80, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20610875

RESUMEN

The purpose of this study was to determine the effect of PMMA polymer on dynamic viscoelasticity and plasticizer leachability of PEMA-based tissue conditioners. One PEMA polymer and one PMMA polymer were used in powder form with four formulations. The combination of 80 wt% ATBC, 15 wt% BPBG and 5 wt% ethyl alcohol was used as the liquid phase. The dynamic viscoelasticity and plasticizer leaching of each specimen were measured after 0, 1, 3, 7, and 14 days of immersion (37 degrees C distilled water) using DMA and HPLC. A significant difference was found among the materials in the dynamic viscoelasticity and leaching of plasticizer. The materials containing 10 wt% PMMA showed the most stable dynamic viscoelasticity, and showed the lowest leaching of plasticizer. The results suggest that the addition of the PMMA polymer to the powder of a tissue conditioner can improve the durability of the PEMA-based tissue conditioner.


Asunto(s)
Materiales Biocompatibles/química , Metilmetacrilatos/química , Polimetil Metacrilato/química , Acondicionamiento de Tejidos Dentales , Química Farmacéutica , Cromatografía Líquida de Alta Presión , Citratos/química , Dibutil Ftalato/análogos & derivados , Dibutil Ftalato/química , Difusión , Módulo de Elasticidad , Elasticidad , Etanol/química , Humanos , Inmersión , Ensayo de Materiales , Plastificantes/química , Polvos , Solventes/química , Temperatura , Factores de Tiempo , Viscosidad , Agua/química
16.
J Prosthet Dent ; 101(3): 205-13, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19231574

RESUMEN

STATEMENT OF PROBLEM: Color stability is an important property of denture base acrylic resin. Color changes indicate aging or damaged dental materials. However, little information is available on the influence of denture cleansers on the color stability of acrylic resins. PURPOSE: The purpose of this study was to determine the influence of denture cleansers on the color stability of 3 different types of acrylic resin. MATERIAL AND METHODS: One heat-polymerized (HP) acrylic denture base resin (Acron), 1 autopolymerized (AP) hard direct reline acrylic resin (Denture Liner), and 1 visible-light-polymerized (VLP) hard direct reline acrylic resin (Tokuso Lite-Rebase) were evaluated. Five specimens of each material, 10 x 10 x 2 mm, were immersed in 1 of 9 commercial denture cleanser solutions or distilled water (control). Color changes were measured with a colorimeter and evaluated using the CIE L*a*b* colorimetric system. Data were analyzed using 1-way and 3-way ANOVA and the Student-Newman-Keuls test (alpha=.05). RESULTS: Significant differences (P<.05) were found among the acrylic resins and denture cleansers in terms of color change (DeltaE) produced after 365 days. The DeltaE values of all denture base acrylic resins increased with time. The DeltaE of the AP acrylic resin was larger than that of the other acrylic resins. The least discoloration was found with ZTC denture cleanser (acid type). The influence of alkaline peroxide-type denture cleanser (Steradent) on the color stability of HP acrylic resin and AP acrylic resin was significantly greater (P<.05) than that of the other cleansers. CONCLUSIONS: These results suggest that the color stability of denture base acrylic resins is influenced by polymerization type and the type of denture cleanser used.


Asunto(s)
Resinas Acrílicas/química , Bases para Dentadura , Limpiadores de Dentadura/efectos adversos , Coloración de Prótesis , Humanos , Polimetil Metacrilato
17.
Dent Mater J ; 27(2): 153-8, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18540387

RESUMEN

The purpose of this study was to compare the influence of three kinds of storage methods on surface roughness of tissue conditioners. Four commercial tissue conditioners (GC Soft Liner, Softone, Fictioner, and Hydro-Cast) were used in this study. Five samples of each material were stored in distilled water, air, and a denture cleanser (Polident). Mean surface roughness (R(a)) values of dental stone casts made from the tissue conditioners were measured after 0, 1, 3, 7, and 14 days of immersion using a profilometer. Significant differences in the R(a) values of the specimens were found among the three storage methods. The values of R(a) significantly increased with increase in immersion time for each storage method, except for the materials stored in air. It was found that the materials stored in air showed the most stable and lowest values of R(a). Results obtained suggested that a tissue conditioner exhibited smooth and minimal change in surface roughness with time when stored in air than in distilled water and denture cleanser.


Asunto(s)
Alineadores Dentales , Aire , Análisis de Varianza , Limpiadores de Dentadura , Porosidad , Propiedades de Superficie , Agua
18.
Dis Colon Rectum ; 50(11): 1887-98, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17882488

RESUMEN

PURPOSE: The prognosis varies greatly in colorectal carcinoma patients, even in the same stage. We examined the association between the expression of matrix metalloproteinases-2, carcinoembryonic antigen, p27 kip1, and clinicopathologic features in patients with colorectal carcinoma to identify a possible panel of tumor markers in predicting prognosis of colorectal carcinoma. METHODS: The expressions of three individual markers in 127 colorectal carcinoma cases were analyzed by immunohistochemistry method. Univariate and multivariate analysis were performed to analyze the expression with the disease-free survival time in colorectal carcinoma. RESULTS: High expression of matrix metalloproteinases-2, carcinoembryonic antigen, and low expression of p27 kip1 were related to poor prognosis in univariate analysis (P = 0.0002; P < 0.0001; P = 0.0008). The expression of matrix metalloproteinases-2, carcinoembryonic antigen, p27 kip1, and tumor differentiation were independent prognostic factors for disease-free survival by Cox regression analysis. The coexpression panel of matrix metalloproteinases-2, carcinoembryonic antigen, and p27 kip had significant prognostic value in all patients (P AB = 0.0103; P(BC) = 0.0068; P CD = 0.0117). Multivariate analysis with Cox regression reveals that coexpression of matrix metalloproteinases-2, carcinoembryonic antigen, and p27 kip1 were independent prognostic factors as tumor differentiation in colorectal carcinoma. In different stages, coexpression tumor markers functioned in Stages II and III but not in the 19 cases of Stage I. The reason might be the number of patients was too small. CONCLUSIONS: The results of this study provided further evidence that the combination of tumor markers of matrix metalloproteinases-2, carcinoembryonic antigen, and p27 kip1 was more informative than any single tumor marker alone for the disease-free survival stratification of colorectal carcinoma. Coexpression of matrix metalloproteinases-2, carcinoembryonic antigen, and p27 kip1 might be a useful survival stratification panel for clinical management.


Asunto(s)
Adenocarcinoma/metabolismo , Adenocarcinoma/enfermería , Antígeno Carcinoembrionario/metabolismo , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/mortalidad , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Inhibidor p27 de las Quinasas Dependientes de la Ciclina , Supervivencia sin Enfermedad , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pronóstico , Análisis de Supervivencia
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(1): 102-5, 2006 Jan.
Artículo en Chino | MEDLINE | ID: mdl-16827354

RESUMEN

BCN, BC2N and BC3N thin films with transmission increasing properties in the ultraviolet region were deposited by RF magnetron sputtering with different sputtering power (80-130 W). Fourier transform infrared absorption and X-ray photoelectron spectroscopy results suggested that the films were atomnic-level hybrids composed of B, 'C and N atoms. The compositions and transmission increasing properties of samples in the ultraviolet region were strongly influenced by sputtering power, which determined the transmission increasing properties in the ultraviolet region by changing compositions. And the lower the atomic number of C in the thin films, the better the transmission increasing properties in the ultraviolet region. The BCN thin films deposited at the sputtering power of 110 W possessed the lowest atonic number of C and the best transmission increasing properties in the ultraviolet region. And the increase in average transmissivity from 200 to 350 nm was about 40% compared with glass.

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