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1.
Small ; 20(26): e2310731, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38247187

RESUMEN

The development of robust adhesive, conductive, and flexible materials has garnered significant attention in the realm of human-machine interface and electronic devices. Conventional preparation methods to achieve these exceptional properties rely on incorporating highly polar raw materials, multiple components, or solvents. However, the overexposure of functional groups and the inherent toxicity of organic solvents often render gels non-stick or potentially biocompatible making them unsuitable for human-contact devices. In this study, a straightforward three-step strategy is devised for preparing responsive adhesive gels without complex components. Structurally conductive poly(N-(2-hydroxyethyl)-acrylamide-co-p-styrene sulfonate hydrate) (PHEAA-NaSS) gels are synthesized by integrating ionic and hydrophilic networks with distinct solvent effects. Initially, the in-suit formed PHEAA-NaSS networks are activated by dimethyl sulfoxide, which substantially increases intramolecular hydrogen bonding and enhances the matrix stretchability and interfacial adhesion. Subsequently, ethanol exchange reduced solvent impact and led to a compact network that limited surface exposure of ionic and hydrophilic groups, resulting in nonstick, robust for convenient storage. Finally, upon contacting with water, the network demonstrates rehydration, resulting in favorable adhesion, biocompatibility, and conductivity. The proposed PHEAA-NaSS/W gels can stably and reliably capture joint motion and electrophysiological signals. Furthermore, this uncomplicated gel preparation method is also applicable to other electrolyte monomers.


Asunto(s)
Materiales Biocompatibles , Conductividad Eléctrica , Geles , Solventes , Dispositivos Electrónicos Vestibles , Solventes/química , Materiales Biocompatibles/química , Geles/química , Humanos , Adhesivos/química
2.
Int J Mol Sci ; 25(8)2024 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-38674133

RESUMEN

The unique zigzag-patterned tea plant is a rare germplasm resource. However, the molecular mechanism behind the formation of zigzag stems remains unclear. To address this, a BC1 genetic population of tea plants with zigzag stems was studied using histological observation and bulked segregant RNA-seq. The analysis revealed 1494 differentially expressed genes (DEGs) between the upright and zigzag stem groups. These DEGs may regulate the transduction and biosynthesis of plant hormones, and the effects on the phenylpropane biosynthesis pathways may cause the accumulation of lignin. Tissue sections further supported this finding, showing differences in cell wall thickness between upright and curved stems, potentially due to lignin accumulation. Additionally, 262 single-nucleotide polymorphisms (SNPs) across 38 genes were identified as key SNPs, and 5 genes related to zigzag stems were identified through homologous gene function annotation. Mutations in these genes may impact auxin distribution and content, resulting in the asymmetric development of vascular bundles in curved stems. In summary, we identified the key genes associated with the tortuous phenotype by using BSR-seq on a BC1 population to minimize genetic background noise.


Asunto(s)
Camellia sinensis , Regulación de la Expresión Génica de las Plantas , Polimorfismo de Nucleótido Simple , RNA-Seq , Camellia sinensis/genética , Camellia sinensis/metabolismo , Tallos de la Planta/genética , Tallos de la Planta/metabolismo , Mutación , Fenotipo , Lignina/metabolismo , Lignina/biosíntesis , Transcriptoma/genética , Perfilación de la Expresión Génica/métodos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
3.
Environ Res ; 229: 116003, 2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37127106

RESUMEN

The complexity of the chemistry behind the hydrothermal conversion is enormous. Components interact with their own physical and chemical structure, making it harsh to understand the conversion as a whole. Herein, the six-water recirculation and loading nano SiO2 experiment in a one-pot hydrothermal carbonization procedure was designed to elucidate the mechanism of regulating the functional groups and microporous structure of the hydrochar surface. The hydrochar prepared by the second circulating liquid and loading nano-SiO2 (HBC-R2/Si) was equipped most enriched functional groups (carboxyl = 11.48 µmol/g, phenolic hydroxyl = 52.98 µmol/g, lactone groups = 46.52 µmol/g) and suitable pore size (1.90 nm-1.93 nm) as a sorbent riched in hemicellulose. The sorption kinetics (equilibrium reached ≈ 480 min) are approximately evenly fitted by the pseudo-second-order, Weber and Morris, and Elovich models, indicating that membranes and particles diffusion, pore diffusion, and surface sorption coexisted in the sorption of methylene blue (MB) on the hydrochar materials. Simultaneously, all hydrochar materials achieved over 25% MB removal within 90 min (liquid membrane diffusion) and over 40% for HBC-R2 and HBC-R2/Si, suggesting that liquid membrane diffusion is the predominant rate-limiting step. Pearson's correlation analysis and Mantel's analysis announced that the cation exchange capacity (CEC), pore size, and carboxyl groups on the hemicellulose affect the sorption capacity by limiting the pore diffusion procedure. However, the CEC and the phenolic hydroxyl groups on the cellulose and hemicellulose affect the sorption rate by limiting membrane diffusion. Three consecutive sorption/desorption cycles confirmed the high stability and reusability of HBC-R2/Si composites.


Asunto(s)
Carbono , Celulosa , Carbono/química , Cinética , Azul de Metileno/análisis , Propiedades de Superficie , Adsorción
4.
BMC Oral Health ; 19(1): 277, 2019 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-31818283

RESUMEN

BACKGROUND: The purpose of the study is to examine the association between tooth loss and hypertension among older community residents in urban China. METHODS: This study included 3677 participants aged ≥50 years from the Shanghai Aging Study. We determined the number of teeth missing from questionnaires. Hypertension was defined as the mean of two measurements of systolic blood pressure (SBP) (140 mmHg or higher), diastolic blood pressure (DBP) (90 mmHg or higher) or physician-diagnosed hypertension confirmed from medical records. A multivariable logistic regression model was used to investigate the association between tooth loss and hypertension. RESULTS: The average number of missing teeth among study participants was 9.67. Among them, participants with hypertension had lost an average of 10.88 teeth, significantly higher than those without hypertension (8.95) (p < 0.0001). After adjusting for covariates (socio-demographic characteristics, health behaviors and other chronic conditions), teeth lost (15 or more) was significantly associated with grade III hypertension, with OR = 1.55(95% CI 1.09-2.20). CONCLUSIONS: Significant tooth loss maybe associated with severe hypertension among older Chinese adults. Prevention of tooth loss is important to the overall health of this population.


Asunto(s)
Pueblo Asiatico/estadística & datos numéricos , Hipertensión/epidemiología , Pérdida de Diente/epidemiología , Anciano , Anciano de 80 o más Años , Presión Sanguínea/fisiología , China/epidemiología , Femenino , Humanos , Hipertensión/complicaciones , Hipertensión/etnología , Vida Independiente , Masculino , Persona de Mediana Edad , Pérdida de Diente/complicaciones , Pérdida de Diente/etnología
5.
J Environ Sci (China) ; 76: 57-64, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30528035

RESUMEN

Endocrine disrupting chemicals (EDCs) in the secondary effluent discharged from wastewater treatment plants are of great concern when water reuse is intended. Ozonation and ultrafiltration (UF) are powerful technologies reported to eliminate EDCs. Due to the importance of effluent organic matters (EfOMs) in secondary effluent, the effects of three kinds of EfOM on the treatment of five EDCs using ozonation and UF were investigated. The three kinds of EfOM studied were humic acid sodium salt (NaAH), bovine serum albumin (BSA) and sodium alginate (NaAg); and the five EDCs were estrone, 17ß-estradiol, estriol, 17α-ethynyl estradiol and bisphenol A. The results showed that EfOM accelerated the decay rate of ozone and inhibited the degradation efficiency of EDCs by ozonation in the order NaAH>BSA>NaAg. The ultraviolet absorbance at 280nm (UVA280) has potential for use as a surrogate indicator to assess EDC removal via ozonation without conducting difficult EDC analyses. When the decline in UVA280 exceeded 18%, the five EDCs had been completely removed. The UF behavior of NaAH, BSA and NaAg was found to follow the cake filtration law. The fouling potential of EfOM followed the order NaAg>NaAH>BSA; while EfOM on the membrane surface enhanced EDC removal in the order NaAH>BSA>NaAg. The mean retention rate of the membrane was increased by 24%, 10% and 8%, respectively. The properties of EDCs and EfOM cakes both influenced the EDC removal rates due to adsorption, size exclusion and charge attraction.


Asunto(s)
Disruptores Endocrinos/química , Disruptores Endocrinos/aislamiento & purificación , Compuestos Orgánicos/química , Ozono/química , Aguas Residuales/química , Purificación del Agua/métodos , Membranas Artificiales , Ultrafiltración , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación
6.
Ergonomics ; 61(9): 1273-1281, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29681228

RESUMEN

Driving may be detrimental to health, with one hypothesis suggesting that driving may elicit an acute stress response and, with repeated exposures, may become a chronic stressor. The present study examined the stress response to driving and the effectiveness of a prior exercise bout in dampening this response. Twenty healthy adults performed three tasks: control, driving and exercise plus driving. Heart rate (HR), heart rate variability (HRV), blood pressure (BP) and cortisol were measured to quantify the acute stress response to each condition. Data indicated a stress response to driving: HR was elevated and HRV was reduced during the driving task compared with control. HR was elevated and HRV was reduced comparing the exercise plus driving with the driving condition. BP and cortisol were not different among conditions. The potential of interventions, such as exercise, to counter daily stressors should be evaluated to safeguard long-term health. Practitioner Summary: this study confirms that driving induces a stress response, with the exercise intervention providing mixed results (an increase in cardiovascular measures and a decrease in cortisol measure trending significance). Given the known consequences of stress and evidence that exercise can mitigate acute stress, further evaluation of exercise interventions is recommended.


Asunto(s)
Conducción de Automóvil/psicología , Ejercicio Físico/fisiología , Frecuencia Cardíaca/fisiología , Hidrocortisona/fisiología , Estrés Psicológico/fisiopatología , Adolescente , Adulto , Anciano , Análisis de Varianza , Presión Sanguínea/fisiología , Femenino , Humanos , Hidrocortisona/análisis , Masculino , Persona de Mediana Edad , Saliva , Estrés Fisiológico , Encuestas y Cuestionarios , Población Urbana , Adulto Joven
7.
Am J Orthod Dentofacial Orthop ; 152(2): 171-177, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28760279

RESUMEN

INTRODUCTION: Tobacco use is related to increased periodontal disease, tooth loss, and decreased success of orthodontic appliances, and it may inhibit orthodontic tooth movement. Most smokers start during adolescence. Since most cessation attempts fail, prevention appears necessary. METHODS: A cross-sectional sample of orthodontic patients reported hypothesized risk factors for smoking and susceptibility to tobacco use initiation. Exploratory analyses regressed susceptibility to tobacco initiation on each hypothesized predictor variable in a separate logistic model that included a standard set of covariates. RESULTS: Significant odds ratios (OR) were found for the presence of a smoker in the home (OR, 2.168; 95% confidence interval [CI], 1.144-4.107), a friend having no-smoking rules in his or her home and car (OR, 0.337; 95% CI, 0.128-0.886), having been offered a cigarette (OR, 4.526; 95% CI, 1.190-17.207), and exposure to tobacco advertisements (OR, 1.910; 95% CI, 1.044-3.496). CONCLUSIONS: Peer, family, and environmental factors appear to increase children's susceptibility to smoking in orthodontic populations. Attention to such factors could help dental clinicians to more effectively identify susceptible young patients in need of antismoking advice. Prospective and experimental studies are required to confirm the role that dental clinicians might play in youth smoking prevention.


Asunto(s)
Ortodoncia/estadística & datos numéricos , Prevención del Hábito de Fumar , Adolescente , Publicidad , Niño , Estudios Transversales , Familia/psicología , Femenino , Humanos , Masculino , Ortodoncia/métodos , Grupo Paritario , Factores de Riesgo , Fumar/psicología
8.
Analyst ; 141(11): 3337-42, 2016 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-27111129

RESUMEN

Elucidating the endocytosis and metabolism of nanoparticles in cells could improve the diagnostic sensitivity and therapeutic efficiency. In this work, we explore the cellular uptake mechanism of a biocompatible nanocrystal nanostructure, graphene-isolated-Au-nanocrystals (GIANs), by monitoring the intrinsic Raman and two-photon luminescence signals of GIANs in live cells. Aptamers functionalized on the GIAN nanostructure through simple, but strong, π-π interactions entered the cells through a clathrin-dependent pathway, while unmodified GIANs mainly entered the cells through a caveolae-mediated endocytosis pathway. Thus, it can be concluded that the mechanism of cellular uptake in these graphene-isolated-Au-nanocrystal nanostructures is determined by the presence or absence of aptamer modification.


Asunto(s)
Endocitosis , Oro/metabolismo , Grafito , Mediciones Luminiscentes , Nanopartículas/metabolismo , Espectrometría Raman , Materiales Biocompatibles/metabolismo , Células HeLa , Humanos , Nanoestructuras
9.
J Am Chem Soc ; 136(39): 13558-61, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-25233109

RESUMEN

Noble metals, especially gold, have been widely used in plasmon resonance applications. Although silver has a larger optical cross section and lower cost than gold, it has attracted much less attention because of its easy corrosion, thereby degrading plasmonic signals and limiting its applications. To circumvent this problem, we report the facile synthesis of superstable AgCu@graphene (ACG) nanoparticles (NPs). The growth of several layers of graphene onto the surface of AgCu alloy NPs effectively protects the Ag surface from contamination, even in the presence of hydrogen peroxide, hydrogen sulfide, and nitric acid. The ACG NPs have been utilized to enhance the unique Raman signals from the graphitic shell, making ACG an ideal candidate for cell labeling, rapid Raman imaging, and SERS detection. ACG is further functionalized with alkyne-polyethylene glycol, which has strong Raman vibrations in the Raman-silent region of the cell, leading to more accurate colocalization inside cells. In sum, this work provides a simple approach to fabricate corrosion-resistant, water-soluble, and graphene-protected AgCu NPs having a strong surface plasmon resonance effect suitable for sensing and imaging.


Asunto(s)
Alquinos/química , Grafito/química , Nanopartículas/química , Plata/química , Cobre/química , Humanos , Células MCF-7 , Tamaño de la Partícula , Polietilenglicoles/química , Espectrometría Raman , Propiedades de Superficie
10.
Front Aging Neurosci ; 15: 1146335, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37139086

RESUMEN

Introduction: The loss of occlusal support due to tooth loss is associated with systemic diseases. However, there was little about the association between occlusal support and cognitive impairment. The cross-sectional study aimed to investigate their association. Methods: Cognitive function was assessed and diagnosed in 1,225 community-dwelling adults aged 60 years or older in Jing'an District, Shanghai. Participants were diagnosed with mild cognitive impairment (MCI) by Peterson's criteria, or dementia, according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. We determined the number of functional occlusal supporting areas according to Eichner classifications. We used multivariate logistic regression models to analyze the relationship between occlusal support and cognitive impairment and mediation effect models to analyze the mediation effect of age. Results: Six hundred sixty participants were diagnosed with cognitive impairment, averaging 79.92 years old. After adjusting age, sex, education level, cigarette smoking, alcohol drinking, cardiovascular disease, and diabetes, individuals with poor occlusal support had an OR of 3.674 (95%CI 1.141-11.829) for cognitive impairment compared to those with good occlusal support. Age mediated 66.53% of the association between the number of functional occlusal supporting areas and cognitive impairment. Discussion: In this study, cognitive impairment was significantly associated with the number of missing teeth, functional occlusal areas, and Eichner classifications with older community residents. Occlusal support should be a significant concern for people with cognitive impairment.

11.
J Mech Behav Biomed Mater ; 129: 105136, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35231728

RESUMEN

Biomechanical performance plays an important role in the long-term service of dental implants. Loosening and fatigue damage of the central screw are the most common problems. This research investigated the effect of the central screw taper angle on the loosening performance and fatigue characteristics of dental implants. Central screws with four taper angles, 30°, 60°, 90° and 180°, were processed and tested. The loosening performance of the screws under initial and postload conditions was compared. Then, the fatigue characteristics of dental implants was measured. Finally, the wear and fracture modes of the screws were observed. The damage locations were verified by finite element analysis (FEA). The results showed that the central screws with 30° taper had substantially better anti-loosening performance and less fretting wear. The central screws with 180° taper had a higher preload, resulting in a longer fatigue life. Furthermore, the fatigue fracture of the central screw occurred at the level of the first thread position, consistent with the FEA results. In the future clinical applications, central screws with a 30° taper angle may improve anti-loosening performance and prolong fatigue life by increasing the tightening torque.


Asunto(s)
Implantes Dentales , Tornillos Óseos , Análisis del Estrés Dental , Análisis de Elementos Finitos , Torque
12.
Sci Rep ; 12(1): 15876, 2022 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-36151250

RESUMEN

A fluorescent porous organic polymer (FPOP) with strong fluorescence and tunable emission colors, was synthesized through a simple cost-effective method via Scholl coupling reaction. Experiments proved the stability and excellent detection and adsorption ability, and microporous nature of the material. Luminescence of FPOP was quenched when addition of nitroaromatic compounds. The properties along with large-scale and low-cost preparation make these FPOP potential candidates for fluorescence detection of nitroaromatic compounds. Additionally, FPOP shows higher adsorption capacity and rate than other reported adsorbents, and has the possibility of being an effective adsorbent for industrial usage. Moreover, a fluorescent test paper was further developed and is found to be sensitive to 10-8 M level, complete with a rapid response time and visual detection. This newly developed strategy may open up an avenue for exploring porous polymers, particularly those with a strong fluorescence, for the large-scale fabrication of FPOP for various advanced applications.


Asunto(s)
Colorantes , Polímeros , Adsorción , Fluorescencia , Porosidad
13.
J Nanosci Nanotechnol ; 11(2): 1425-8, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21456204

RESUMEN

Conjugated linoleic acid-coupled Pluronic F127 (Plu-CLA) is an effective drug delivery system with numerous advantages and anti-cancer activity. 5-FU administered in Plu-CLA hydrogel (P-FU) led to the significant enhancement of tumor growth suppression and cellular apoptosis. Moreover, growth of hepatic and intraperitoneal metastases in vivo was significantly reduced in mice treated with P-FU. Therefore, Plu-CLA could be a potential intraperitoneal carrier for hydrophilic 5-FU for the effective treatment of metastatic colon cancer.


Asunto(s)
Antineoplásicos/administración & dosificación , Neoplasias del Colon/tratamiento farmacológico , Fluorouracilo/administración & dosificación , Animales , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Línea Celular Tumoral , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Sistemas de Liberación de Medicamentos , Hidrogeles/administración & dosificación , Ácidos Linoleicos Conjugados/administración & dosificación , Neoplasias Hepáticas Experimentales/tratamiento farmacológico , Neoplasias Hepáticas Experimentales/secundario , Ratones , Ratones Endogámicos BALB C , Nanotecnología , Neoplasias Peritoneales/tratamiento farmacológico , Neoplasias Peritoneales/secundario , Poloxámero/administración & dosificación , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo
14.
Mater Sci Eng C Mater Biol Appl ; 110: 110700, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32204014

RESUMEN

In this work, tantalum thin films were prepared on titanium substrates by an ion beam sputtering method. Tantalum thin films were irradiated by gamma-ray with different total dose levels. The effect of irradiation on the phase composition, microstructure, surface morphology, and chemical resistance were analyzed. Besides, in vitro cytocompatibility of tantalum films treated with different radiation doses were evaluated via 3T3-E1 cells. Experimental results showed that higher radiation dose resulted in reductions in crystalline nature, denser morphology, lower elastic modulus, less oxygen vacancies and better corrosion resistance. Additionally, 3T3-E1 cells adhered and spread well on the surface of tantalum film with irradiation exposure to 10 kGy. The dense surface morphology, less density of chemical defects and amorphous phase produced by the gamma-ray irradiation played a major role in the improvement of mechanical compatibility, electrochemical stability property along with the cytocompatibility of the tantalum films.


Asunto(s)
Materiales Biocompatibles Revestidos/química , Tantalio/química , Células 3T3 , Animales , Línea Celular , Corrosión , Módulo de Elasticidad/efectos de los fármacos , Rayos gamma , Ensayo de Materiales/métodos , Ratones , Propiedades de Superficie/efectos de los fármacos , Titanio/química
15.
Seizure ; 65: 42-47, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30611009

RESUMEN

PURPOSE: We evaluated the oral health and dental status of people with epilepsy, and their relationship to seizure frequency, in a community cohort in rural China. METHODS: A cross-sectional study of people with epilepsy was carried out in areas in Henan, Shanxi and Ningxia provinces of China. All participants underwent a specially designed "Oral health and Dental status Questionnaire". Univariate and multivariate analyses were used to explore the relationships between seizure frequency and oral health and dental status. RESULTS: A total of 875 people participated. Almost two thirds (65.8%) reported brushing their teeth at least once a day but 634 (73.0%) brushed their teeth for less than 3 min each time. Only 80 (9.1%) had visited a dental clinic in the previous year. Multivariate logistic regression analysis showed that having 1-4 seizures/month (OR 0.60, 95%CI 0.40-0.90) or >4 seizures/month (OR 0.38, 95%CI 0.22-0.66) was associated with decreased odds of brushing teeth at least once a day, and higher seizure frequency was associated with increased odds of dental injury due to seizures (OR 2.07, 95%CI 1.22-3.50 for <1 seizure/month; OR 2.12, 95%CI 1.25-3.58 for 1-4 seizures/month; OR 3.09, 95%CI 1.57-6.07 for >4 seizures/month). CONCLUSION: Seizure frequency was significantly associated with seizure-related dental injury, and with the lack of good oral health practice. Improvement in the oral health of people with epilepsy in resource-poor areas should be encouraged.


Asunto(s)
Epilepsia/epidemiología , Epilepsia/fisiopatología , Salud Bucal , Población Rural , Enfermedades Dentales/epidemiología , Adulto , China/epidemiología , Estudios de Cohortes , Estudios Transversales , Caries Dental , Ecosistema , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios
16.
JAMA Otolaryngol Head Neck Surg ; 145(1): 53-61, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30452499

RESUMEN

Importance: Oral cavity squamous cell carcinoma (OCSCC) is associated with often-delayed clinical diagnosis, poor prognosis, and expensive therapeutic approaches. Prognostic accuracy is important in improving treatment outcomes of patients with this disease. Objectives: To assess lymph node ratio (LNR) and other factors in estimating response to treatment and provide prognostic information helpful for clinical decision making. Design, Setting, and Participants: A retrospective cohort study was conducted from January 1, 2000, to December 31, 2015, at an academic hospital in Denver, Colorado. Participants included 149 patients with primary OCSCC who received curative-intent surgery and/or postoperative adjuvant therapies. Analysis was performed from December 8, 2017, to August 15, 2018. Main Outcomes and Measures: Overall survival (OS), disease-free survival (DFS), locoregional disease-free survival (LRDFS), and distant metastasis-free survival (DMDFS) adjusted for known prognostic risk factors, as well as correlation of LNR with other histopathologic prognostic factors. Results: Of the 149 patients included in analysis, 105 were men (70.5%); the median age at diagnosis was 59 years (range, 28-88 years). Using the Kaplan-Meier method, the 5-year survival estimates for OS rate was 40.4% (95% CI, 31.3%-49.3%); DFS, 48.6% (95% CI, 38.6%-58.0%); LRDFS, 57.7% (95% CI, 46.6%-67.2%); and DMDFS, 74.7% (95% CI, 65.1%-82.0%). The median follow-up was 20 months for all patients and 34.5 months (range, 0-137 months) for surviving patients. Nonwhite race (hazard ratio [HR], 2.15; 95% CI, 1.22-3.81), T3-T4 category (HR, 1.99; 95% CI, 1.18-3.35), and LNR greater than 10% (HR, 2.71; 95% CI, 1.39-5.27) were associated with poorer OS. Nonwhite patients also had higher risk of locoregional failures (HR, 2.47; 95% CI, 1.28-4.79), whereas women were more likely to have distant metastasis (HR, 2.55; 95% CI, 1.14-5.71). Floor-of-mouth subsite had fewer locoregional recurrences than did other subsites (HR, 0.45, 95% CI, 0.21-0.99). An LNR greater than 10% independently was associated with worse OS (HR, 2.71; 95% CI, 1.39-5.27), DFS (HR, 2.48; 95% CI, 1.18-5.22), and DMDFS (HR, 6.05; 95% CI, 1.54-23.71). The LNR was associated with N-stage (Cramer V, 0.69; 95% CI, 0.58-0.78), extracapsular extension (Cramer V, 0.55; 95% CI, 0.44-0.66), lymphovascular invasion (Cramer V, 0.46; 95% CI, 0.27-0.61); number of excised lymph nodes (Cramer V, 0.24; 95% CI, 0.06-0.37), margin (Cramer V, 0.22; 95% CI, 0.05-0.38), and tumor thickness combined with depth of invasion (Cramer V, 0.25; 95% CI, 0.05-0.38). Conclusions and Relevance: Locoregional treatment failure remained the predominant pattern of failure. An advanced pathologic stage and nonwhite race were found to be associated with worse outcomes. The findings from this study suggest that LNR is the most robust prognostic factor and appears to have implications for risk stratification in this disease.


Asunto(s)
Carcinoma de Células Escamosas/patología , Ganglios Linfáticos/patología , Neoplasias de la Boca/patología , Recurrencia Local de Neoplasia/patología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/terapia , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Escisión del Ganglio Linfático , Metástasis Linfática , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/mortalidad , Neoplasias de la Boca/terapia , Recurrencia Local de Neoplasia/etiología , Recurrencia Local de Neoplasia/mortalidad , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Factores Socioeconómicos , Análisis de Supervivencia
17.
J Cell Physiol ; 214(2): 283-94, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17654485

RESUMEN

We previously reported that PEGylated conjugated linoleic acid (PCLA) as a pro-drug treatment of cultures of 3T3-L1 cells containing differentiated adipocytes caused de-differentiation by downregulation of PPARgamma2-induced adipogenesis, and cell apoptosis induced by PCLA was lower than that induced by conjugated linoleic acid (CLA) owing to the biocompatible and hydrophilic properties of poly(ethylene glycol) (PEG). To further investigate our previous observations, the present study is designed to evaluate the lipolytic action of PCLA and its role in biochemical signaling pathways of 3T3-L1 cells when compared to the CLA itself. Although both CLA and PCLA stimulated lipolysis, our results indicated a sensitivity difference between CLA and PCLA treatment: a time-dependent effect on lipolysis and p-extracellular signal-related kinases (ERK) expression was observed for PCLA-treated, but not for CLA-treated cultures. Also, the induction by PCLA of mitogen-activated protein kinase kinase (MEK)/ERK mitogen-activated protein kinase (MAPK) activation was linked to secretion of adipo-cytokines, interleukin-6 (IL-6), and interleukin-8 (IL-8), in time-dependent manners. Interestingly, adenylyl cyclase inhibitor, 2', 5'-dideoxyadenosine (DDA), pre-treatment did not prevent PCLA-stimulated lipolysis. In fact, isoproterenol, but not PCLA, caused a significant increase in cyclic adenosine monophosphate (cAMP) levels, suggesting that the PCLA-induced lipolysis was not mediated in the conventional cAMP-dependent pathway and the cAMP was the intracellular mediator for isoproterenol-induced lipolysis. Overall, our findings provide support for a role for PCLA as a pro-drug in the regulation of metabolism in adipose tissue.


Asunto(s)
Adipocitos/efectos de los fármacos , Adipoquinas/metabolismo , AMP Cíclico/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Ácidos Linoleicos Conjugados/farmacología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Polietilenglicoles/química , Transducción de Señal , Células 3T3-L1 , Inhibidores de Adenilato Ciclasa , Adipocitos/metabolismo , Adipoquinas/análisis , Animales , Butadienos/farmacología , Radioisótopos de Carbono/metabolismo , Diferenciación Celular , Células Cultivadas , AMP Cíclico/análisis , Didesoxiadenosina/análogos & derivados , Didesoxiadenosina/farmacología , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Fluoresceína-5-Isotiocianato , Técnica del Anticuerpo Fluorescente Indirecta , Colorantes Fluorescentes , Glicerol/análisis , Glicerol/metabolismo , Isoproterenol/farmacología , Lipólisis/efectos de los fármacos , Ratones , Peso Molecular , Nitrilos/farmacología , Ácido Oléico/análisis , Ácido Oléico/metabolismo , Rodaminas , Factores de Tiempo
18.
Eur J Pharm Biopharm ; 70(2): 621-6, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18573337

RESUMEN

The objective of this study was to investigate whether PEGylated conjugated linoleic acid (PCLA), as compared with conjugated linoleic acid (CLA) alone, displays anti-cancer properties in MCF-7 breast cancer cells. To generate PCLA, CLA was simply coupled to poly(ethylene glycol) (PEG) at the melting state of PEG without a solvent or a catalyst. The coupling reaction generated an ester linkage between the carboxyl group of CLA and hydroxyl one of PEG. The half-life of the generated PCLA was 52h at pH 7.4 at 37 degrees C, indicating that PCLA potentially acts as a pro-drug. Apoptosis of MCF-7 breast cancer cells treated with PCLA showed a dose response to PCLA concentration during treatment. In addition, pro-apoptotic proteins such as Bax were up-regulated, whereas anti-apoptotic proteins, such as Bcl-2, were down-regulated by treatment with both CLA and PCLA. The tumor suppressor gene p53 was significantly up-regulated by treatment with increasing concentrations of PCLA, suggesting that PCLA-induced apoptosis is regulated by a p53-mediated signaling pathway. Overall, the anti-cancer effects of PCLA on MCF-7 breast cancer cells may have therapeutic significance.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Ácidos Linoleicos Conjugados/farmacología , Polietilenglicoles/farmacología , Profármacos/farmacología , Transducción de Señal/fisiología , Proteína p53 Supresora de Tumor/fisiología , Animales , Neoplasias de la Mama/patología , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Semivida , Humanos , Ácidos Linoleicos Conjugados/química , Ratones , Células 3T3 NIH , Polietilenglicoles/química
19.
Int J Pharm ; 359(1-2): 205-10, 2008 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-18490120

RESUMEN

The aim of this study was using Eudragit-cysteine conjugate to coat on chitosan microspheres (CMs) for developing an oral protein drug delivery system, having mucoadhesive and pH-sensitive property. Bovine serum albumin (BSA) as a protein model drug was loaded in thiolated Eudragit-coated CMs (TECMs) to study the release character of the delivery system. After thiolated Eudragit coating, it was found that the release rate of BSA from BSA-loaded TECMs was observably suppressed at pH 2.0 PBS solution, while at pH 7.4 PBS solution the BSA can be sustainingly released for several hours. The structural integrity of BSA released from BSA-loaded TECMs was guaranteed by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and circular dichroism (CD) spectroscopy. The mucoadhesive property of TECMs was evaluated and compared with CMs and Eudragit-coated chitosan microspheres (ECMs). It was confirmed that after coating thiolated Eudragit, the percentage of TECMs remained on the isolated porcine intestinal mucosa surface was significantly higher than those of CMs and ECMs. Likewise, gamma camera imaging of Tc-99m labeled microsphere distribution in rats after oral administration also suggested that TECMs had comparatively stronger mucoadhesive characters. Therefore, our results indicated that TECMs have potentials to be an oral protein drug carrier.


Asunto(s)
Quitosano/química , Microesferas , Ácidos Polimetacrílicos/química , Albúmina Sérica Bovina/química , Adhesividad , Administración Oral , Animales , Bovinos , Dicroismo Circular , Portadores de Fármacos/química , Electroforesis en Gel de Poliacrilamida , Femenino , Concentración de Iones de Hidrógeno , Mucosa Intestinal/metabolismo , Ratas , Ratas Sprague-Dawley , Albúmina Sérica Bovina/farmacocinética , Compuestos de Sulfhidrilo/química , Porcinos , Distribución Tisular
20.
Cancer Lett ; 254(2): 244-54, 2007 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-17482349

RESUMEN

This study is designed to evaluate whether conjugated linoleic acid-coupled Pluronic F127 (Plu-CLA) enhances anticancer efficacy in MCF-7 breast cancer cells when compared to conjugated linoleic acid (CLA) itself. CLA was simply coupled to Pluronic F127 through ester linkage between carboxyl group of CLA and hydroxyl one of Pluronic at melting state without solvent or catalyst. Plu-CLA significantly enhanced apoptosis with increasing concentration compared with CLA itself. Moreover, it was found that p53, p21, and Bax were up-regulated, whereas Bcl-2 and procaspase 9 were down-regulated with increasing concentration of Plu-CLA. These results were attributed to the sensitization activity of Pluronic F127.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias de la Mama/patología , Ácidos Linoleicos Conjugados/uso terapéutico , Poloxámero/uso terapéutico , Antineoplásicos/síntesis química , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Femenino , Humanos
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