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1.
Cell ; 160(3): 393-406, 2015 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-25601461

RESUMEN

Colorectal cancer primarily metastasizes to the liver and globally kills over 600,000 people annually. By functionally screening 661 microRNAs (miRNAs) in parallel during liver colonization, we have identified miR-551a and miR-483 as robust endogenous suppressors of liver colonization and metastasis. These miRNAs convergently target creatine kinase, brain-type (CKB), which phosphorylates the metabolite creatine, to generate phosphocreatine. CKB is released into the extracellular space by metastatic cells encountering hepatic hypoxia and catalyzes production of phosphocreatine, which is imported through the SLC6A8 transporter and used to generate ATP­fueling metastatic survival. Combinatorial therapeutic viral delivery of miR-551a and miR-483-5p through single-dose adeno-associated viral (AAV) delivery significantly suppressed colon cancer metastasis, as did CKB inhibition with a small-molecule inhibitor. Importantly, human liver metastases express higher CKB and SLC6A8 levels and reduced miR-551a/miR-483 levels relative to primary tumors. We identify the extracellular space as an important compartment for malignant energetic catalysis and therapeutic targeting.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Neoplasias Hepáticas/secundario , MicroARNs/metabolismo , Metástasis de la Neoplasia/genética , Animales , Línea Celular Tumoral , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Forma BB de la Creatina-Quinasa/metabolismo , Metabolismo Energético , Matriz Extracelular , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Metástasis de la Neoplasia/patología , Proteínas del Tejido Nervioso/metabolismo , Proteínas de Transporte de Neurotransmisores en la Membrana Plasmática/metabolismo
2.
Electrophoresis ; 39(11): 1375-1381, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29500834

RESUMEN

Methyl parathion (MP) is a highly toxic organophosphate and its exposure may lead to substantial adverse effects to human health. The existence of 4-nitrophenol (4-NP) in the form of free phenol, glucuronide (4-NP-G) or as a sulfate ester (4-NP-S) can be used as biomarkers to assess the duration and extent of MP exposure. In this work, a MC-CE device incorporating post-CE amperometric detection using multi-walled carbon nanotubes (MWNTs) modified carbon fiber microelectrode (CFME) was fabricated and assessed for simultaneous determination of 4-NP, 4-NP-G, and 4-NP-S in human urine. The detection sensitivity and stability was greatly enhanced by the modification of MWNTs. The capability of the MC-CE device with dual MWNTs modified CFME for detecting impurity was assessed and reliability established by high recoveries from 95 to 97% for spiked MP biomarkers. The method developed is shown to provide a simple, sensitive, and reliable means for monitoring 4-NP, 4-NP-G, and 4-NP-S in human urine.


Asunto(s)
Electroforesis Capilar/instrumentación , Electroforesis Capilar/métodos , Humanos , Metil Paratión/metabolismo , Metil Paratión/orina , Microelectrodos , Microfluídica , Nanotubos de Carbono
3.
J Sep Sci ; 38(18): 3271-3278, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26178772

RESUMEN

A new method for the determination of taurine was developed based on indirect amperometric detection after capillary electrophoresis. A serial dual-electrode detector comprising an on column Pt film electrode (upstream electrode) and an end column Pt microdisk electrode (downstream electrode) was utilized to conduct the indirect amperometric detection. Bromide is oxidized to bromine at upstream electrode and reduced back to bromide at downstream electrode. Since taurine can react with bromine quantitatively and rapidly, its concentration can therefore be determined by the decrease of the current for bromine reduction at the downstream electrode. Principal experimental parameters governing the analytical performance were investigated and optimized. Under the optimal conditions, taurine can be baseline separated from interfering amino acids and the detection limit of 0.18 µM was obtained with a linear correlation coefficient of 0.999 over the concentration range of 0.5-60 µM. The developed method has been successfully applied in the determination of taurine in human tear fluid. The taurine level obtained was in good agreement with previous reports and recoveries for taurine spiked ranged from 92-95% with relative standard deviations within 4.6%, demonstrating the reliability of the developed method in the determination of taurine in human tear fluid.

4.
Electrophoresis ; 35(24): 3556-63, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25223840

RESUMEN

A new serial dual-electrode detector for CE has been designed and fabricated for postcolumn reaction detection based on electrogenerated bromine. A coaxial postcolumn reactor was employed to introduce bromide reagent and facilitate the fabrication of upstream generation electrode by simply sputtering Pt film onto the outer surface of the separation capillary. Bromide introduced could be efficiently converted to bromine at this Pt film electrode and subsequently detected by the downstream Pt microdisk detection electrode. Analytes that react with bromine could be determined by the decrease of bromine reduction current at the downstream electrode resulting from the reaction between analytes and bromine. The effects of serial dual-electrode detector working conditions including electrode potentials, bromide flow rate, and bromide concentration on analytical performance were investigated using glutathione (GSH) and glutathione disulfide (GSSG) as test analytes. Under the optimal conditions, detection limits down to 0.16 µM for GSH and 0.14 µM for GSSG (S/N = 3) as well as linear working ranges of two orders of magnitude for GSH and GSSG were achieved. Furthermore, the separation efficiency obtained by our dual-electrode detector design was greatly improved compared with previous reported design. The developed method has been successfully applied to determine the GSH and GSSG impurity in commercial GSH supplement.


Asunto(s)
Bromo/química , Electroforesis Capilar/instrumentación , Electroforesis Capilar/métodos , Electrodos , Diseño de Equipo , Glutatión/análisis , Disulfuro de Glutatión/análisis , Límite de Detección , Modelos Lineales , Modelos Químicos , Reproducibilidad de los Resultados
5.
Electrophoresis ; 35(11): 1728-34, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25025095

RESUMEN

To determine the adulteration of soybean proteins in dairy product, a microchip-CE device was developed to isolate selected fraction of soybean and milk proteins in pI range from 5.5 ∼ 7.0 by 1D IEF, followed by ITP/CZE in the embedded capillary for preconcentration, separation and UV detection at 280 nm. Compared to IEF-CZE without ITP preconcentration, the enhancement factor (EF) in detection of soybean proteins was 20 times. Adulteration of 0.1% soybean protein in total dairy proteins can be detected in less than 10 min.


Asunto(s)
Productos Lácteos/análisis , Electroforesis por Microchip/instrumentación , Análisis de los Alimentos/instrumentación , Calidad de los Alimentos , Proteínas de la Leche/análisis , Proteínas de Soja/análisis , Diseño de Equipo , Proteínas de la Leche/aislamiento & purificación , Proteínas de Soja/aislamiento & purificación
6.
J Behav Med ; 37(3): 369-80, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23404136

RESUMEN

There has been little research examining the psychological antecedents of safety-oriented behavior aimed at reducing myopia risk. This study utilizes self-determination theory (SDT) and the theory of planned behavior (TPB) to understand the role of motivational and social-cognitive factors on individuals' near-work behavior. Adopting a prospective design, undergraduate students (n = 107) completed an initial questionnaire based on SDT in week 1, a second questionnaire containing measures of TPB variables in week 2, and objective measures of reading distance and visual acuity in week 6. The data were analyzed by variance-based structural equation modeling. The results showed that perceived autonomy support and autonomous motivation from SDT significantly predicted attitude, subjective norm, and perceived behavioral control from the TPB. These social-cognitive factors were significantly associated with intention and intention significantly predicted reading distance. The relationships in the model held when controlling for visual acuity. In conclusion, the integrated model of SDT and the TPB may help explain myopia-preventive behaviors.


Asunto(s)
Conductas Relacionadas con la Salud , Miopía/prevención & control , Autonomía Personal , Teoría Psicológica , Agudeza Visual/fisiología , Adolescente , Adulto , Femenino , Humanos , Control Interno-Externo , Masculino , Modelos Psicológicos , Estudiantes/psicología , Universidades , Adulto Joven
7.
Electrophoresis ; 34(20-21): 2962-9, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24037989

RESUMEN

Optimization based on central composite design (CCD) for enantioseparation of anisodamine (AN), atenolol (AT), and metoprolol (ME) in human urine was developed using a microfluidic chip-CE device. Coupling the flexible and wide working range of microfluidic chip-CE device to CCD for chiral separation of AN, AT, and ME in human urine, a total of 15 experiments is needed for the optimization procedure as compared to 75 experiments using the normal one variable at a time optimization. The optimum conditions obtained are found to be more robust as shown by the curvature effects of the interaction factors. The developed microfluidic chip-CE-ECL system with adjustable dilution ratios has been validated by satisfactory recoveries (89.5-99% for six enanotiomers) in urine sample analysis. The working range (0.3-600 µM), repeatability (3.1-4.9% RSD for peak height and 4.0-5.2% RSD for peak area), and detection limit (0.3-0.6 µM) of the method developed are found to meet the requirements for bedside monitoring of AN, AT, and ME in patients under critical conditions. In summary, the hyphenation of CCD with the microfluidic chip-CE device is shown to offer a rapid means for optimizing the working conditions on simultaneous separation of three racemic drugs using the microfluidic chip-CE device developed.


Asunto(s)
Antiarrítmicos/orina , Atenolol/orina , Electroforesis por Microchip/instrumentación , Metoprolol/orina , Alcaloides Solanáceos/orina , Antiarrítmicos/aislamiento & purificación , Atenolol/aislamiento & purificación , Diseño de Equipo , Humanos , Límite de Detección , Mediciones Luminiscentes/instrumentación , Metoprolol/aislamiento & purificación , Reproducibilidad de los Resultados , Alcaloides Solanáceos/aislamiento & purificación , Estereoisomerismo
8.
Artículo en Inglés | MEDLINE | ID: mdl-36767942

RESUMEN

Iron deficiency (ID) is a prevalent nutritional deficiency affecting children/adolescents worldwide. We reported (1) the prevalence of ID and ID with anemia (IDA) among Chinese school-aged adolescents, (2) clinical and dietary predictors of iron status, and (3) its impact on health-related qualities of life (HRQoL). This cross-sectional study recruited 183 boys and 340 girls (mean age = 17.55) from 16 schools in Hong Kong. ID is defined as serum ferritin <15 µg/L. The participants reported their dietary habits, menstrual patterns (girls), and HRQoL using structured questionnaires. The overall prevalence of ID was 11.1%. None of the boys had ID or IDA. Among girls, the rate of ID was 17.1% and IDA was 10.9%. One-third (36.3%) reported a regular habit of skipping ≥1 meal/day. Lower ferritin was found in adolescents who skipped meals (Est = -35.1, p = 0.017). Lower ferritin is correlated with poorer school functioning (Est = 0.81, p = 0.045) and fatigue (Est = 0.92, p = 0.016). Skipping meals is associated with poorer physical (p = 0.0017) and school functioning (p = 0.027). To conclude, 1 in 10 school-aged adolescents in Hong Kong are iron-deficient. The ID rate in girls (17.1%) is similar to that in other industrialized countries (5.2-16.6%). Future work should promote awareness on the potential health consequences of poor dietary habits on ID and the well-being of adolescents.


Asunto(s)
Anemia Ferropénica , Deficiencias de Hierro , Masculino , Niño , Femenino , Humanos , Adolescente , Anemia Ferropénica/epidemiología , Hong Kong/epidemiología , Calidad de Vida , Prevalencia , Estudios Transversales , Hierro , Ferritinas
9.
J Clin Ultrasound ; 40(2): 79-84, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22105470

RESUMEN

PURPOSE: To evaluate the repeatability and reproducibility of intima thickness (IT) measurements at different sites along the common carotid artery and compare with intima-media thickness (IMT) measurements. METHODS: Ultrasound examinations of common carotid artery were performed in 30 healthy subjects and 20 patients with diabetes mellitus. Carotid IT and IMT were measured at 10 mm, 13 mm, and 16 mm upstream from the carotid bulb. Each subject was scanned by three operators to evaluate inter-operator reproducibility. Each operator scanned the subjects twice to evaluate intra-operator repeatability. Inter-equipment reproducibility of the measurements was evaluated. RESULTS: The inter-operator reproducibility for measuring carotid IT at the three sites was 81.5%, 81.9% and 69.1%, respectively, slightly lower than carotid IMT measurement (89.7%, 86.5%, 75.2%, respectively). The intra-operator repeatability for carotid IT measurement at the three sites ranged 76.9-89.5%, 67.4-90.3%, and 55.2-70.5%, respectively, and was lower than for IMT measurement (86.5-96.9%, 87.6-95.7%, 79.9-86.5%, respectively). The inter-equipment reproducibility of IMT (75.7-86.6%) was slightly better than for IT measurement (71.4-75.9%). CONCLUSIONS: Ultrasonographic measurement of carotid IT is repeatable and reproducible, although not as good as IMT. Measurements preformed 10 mm to 13 mm upstream from the carotid bulb yield more repeatable and reproducible results.


Asunto(s)
Arteria Carótida Común/diagnóstico por imagen , Túnica Íntima/diagnóstico por imagen , Adulto , Anciano , Análisis de Varianza , Diabetes Mellitus Tipo 2/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Túnica Media/diagnóstico por imagen , Ultrasonografía
10.
Front Public Health ; 10: 924434, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36187639

RESUMEN

Background: A 3-month parent education program was designed and implemented in Hong Kong to improve physical literacy (PL) among primary school children and their parents during the COVID-19 pandemic. This study aims to probe into the acceptability of the intervention from parental perspectives, providing more insights for future implementation. Methods: Following the 3-month parent-focused PL program, 16 parents (mean age = 43.73 years, 15 mothers) were recruited to participate in semi-structured individual interviews in June 2021. Interviews were analyzed using thematic analysis in NVivo 12. Two coders analyzed interview transcripts deductively based on the interview guide and social cognitive theory (SCT). Results: Three themes were identified that captured the acceptability of the program: (1) Addressing needs through appropriate delivery enhances acceptability of intervention; (2) Positive behavioral and psychological changes to families; (3) Appropriate support of environmental factors can enhance the sustainability of program effects. The high levels of acceptability were attributable to the fact that parents were able to learn and be a gatekeeper to impact their children positively. Moreover, the design and contents of the program were appropriate for the participating parents because the program provided adequate learning resources and interactive learning support without being overly rigid, and the online learning mode was feasible and convenient. Consequent to their participation in the program, parents expressed that they became more aware of the importance of PL, established physical activity routines with their children, and modified their parenting styles which resulted in improved parent-child relationships. Conclusions: The current study provided evidence that engaging parents in the intervention was feasible and acceptable approach in supporting both parents and children to establish physically active routines in the family setting. The insights gained regarding the appropriateness and acceptability of the program in this specific context may be used to inform the design, implementation and sustainability of other parent-focused PL programs.


Asunto(s)
COVID-19 , Alfabetización , Adulto , COVID-19/prevención & control , Niño , Femenino , Humanos , Pandemias , Responsabilidad Parental/psicología , Padres/psicología
11.
Electrophoresis ; 32(23): 3437-45, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22134981

RESUMEN

A microchip-CE device was fabricated for bed-side monitoring of nephrolithiasis biomarkers in urine by incorporating on-chip continuous passive mixing and standard addition to reduce sample matrix interference, increase sample throughput and eliminate accessories for active mixing. Under optimized conditions with buffer containing 20 mM borate and 0.5 mM CTAB at pH 10.3, sample and standards injected electrokinetically at -350 V for 10 s for online mixing in a Y-merging flow microchannel prior to CE separation and UV detection at 210 nm, both inhibitors (citrate, CA) and promoters (oxalate, OA and uric acid, UA) for nephrolithiasis can be separated and determined in human urine in a single run completed within 10 min after a simple 50-fold sample dilution and filtering. Satisfactory working ranges from 0.13-40, 0.25-40 and 0.025-40 mM, LOD 2.6, 6.1 and 0.7 µM, repeatability (%RSD, n=5) for migration time 1.40, 1.43, 0.47 and peak area 4.46, 6.10, 1.98, respectively, for CA, OA and UA are obtained for urine samples. The use of on-chip standard addition is shown to improve repeatability of the migration time, assist the identification of nephrolithiasis markers from difficult samples with noisy baseline and enlarge the working range for nephrolithiasis marker determination. The device developed can be used for both routine and emergency monitoring to deliver results on demand for bedside monitoring and public health protection. It provides an early detection of nephrolithiasis to enable timely treatments, ease anxiety of parents for neonates consuming suspected contaminated food, and quick results for patients in a critical condition.


Asunto(s)
Electroforesis por Microchip/instrumentación , Electroforesis por Microchip/métodos , Nefrolitiasis/orina , Biomarcadores/orina , Ácido Cítrico/orina , Diseño de Equipo , Humanos , Límite de Detección , Nefrolitiasis/diagnóstico , Oxalatos/orina , Reproducibilidad de los Resultados , Factores de Tiempo , Ácido Úrico/orina
12.
Electrophoresis ; 32(23): 3406-14, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22134979

RESUMEN

To replace the time-consuming sample pretreatment procedure, a microfluidic chip-CE device incorporating on-chip sample desalting/preconcentration with transient isotachophoresis (ITP)/capillary zone electrophoresis (CZE) was fabricated to perform sequential on-chip sample pretreatment and CE determination of four urinary proteins in clinical samples. On-chip sample desalting, clean-up and analyte preconcentration enable removing interfering sample matrix prior to transferring analytes to separation capillary for transient ITP/CZE determination. Four important urinary proteins transferrin, ß2-microglobulin, human serum albumin (HSA) and immunoglobulin G (IgG), investigated were shown to achieve quantitation limits sufficiently high to meet medical requirements, sensitivity enhancement up to 40-fold and detection limits down to 0.3, 0.05, 0.6, 0.5 mg/L, respectively. Compared to the stacking effect, the use of a large sample size was found to be the major factor for sensitivity enhancement. The method reliability is established by close to 100% recoveries and statistical agreement of results from the method developed with currently used clinical radio-immunoassay method for all four proteins investigated. Moreover, an assay time of less than 10 min is needed in the method developed as compared to 7 h for the radio-immunoassay method.


Asunto(s)
Electroforesis por Microchip/instrumentación , Electroforesis por Microchip/métodos , Isotacoforesis/instrumentación , Isotacoforesis/métodos , Proteínas/análisis , Proteinuria/orina , Diseño de Equipo , Humanos , Inmunoglobulina G/orina , Radioinmunoensayo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Albúmina Sérica , Factores de Tiempo , Transferrina/orina , Microglobulina beta-2/orina
13.
Dev Psychol ; 57(11): 1796-1809, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34914446

RESUMEN

Tuning in to Kids (TIK) is a parenting program that focuses on emotion coaching and is evidenced to be effective in Western populations. This study used a randomized controlled trial to examine the intervention effects of TIK on Chinese parents of low to middle socioeconomic status in Hong Kong. One hundred four parents (99 mothers and five fathers; Mage in years = 37.92) of preschoolers aged 3-6 years were randomly assigned to the experimental (n = 54) or waitlist control group (n = 50). Parent and child outcomes were assessed at baseline (Time 1), immediately after the 6-week intervention (Time 2), and 6 weeks postintervention (Time 3), using the Alabama Parenting Questionnaire, Coping with Children's Negative Emotions Scale, Parenting Stress Index-Short Form, and Emotion Regulation Checklist. The experimental group reported significant reductions in punitive parenting and parenting stress at Time 2, and these effects were maintained at Time 3. Delayed improvements in parents' use of expressive encouragement and children's emotion lability/negativity were observed at Time 3 in the experimental group. The immediate intervention effects were replicated in the waitlist control group at Time 3 after they attended the training. This study represented one of the few randomized controlled trials of TIK conducted in a non-Western sample. Our results corroborated the findings of prior studies of TIK and provided preliminary support for its effectiveness across different cultural contexts. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Asunto(s)
Tutoría , Responsabilidad Parental , Niño , Emociones , Hong Kong , Humanos , Padres
14.
Electrophoresis ; 31(13): 2192-9, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20593393

RESUMEN

A new dual opposite carbon-fiber micro-disk electrode detector was fabricated and tested for hyphenation with CE in the polyphenol determination. Under optimized conditions, CE-dual opposite carbon-fiber micro-disk electrode was found able to baseline separate and determine five important polyphenols (trans-resveratrol, (+)-catechin, (-)-epicatechin, quercetin and gallic acid) in red wine within 16 min with low detection limit (0.031-0.21 mg/L) and satisfactory repeatability (2.0-3.3% RSD, n=5). The opposite dual electrode enables simultaneous determination of CE eluents for current ratio measured at +0.8 and +1.0 V versus Ag/AgCl for the peak purity assessment. The capability to identify the presence of co-migrating impurities in given polyphenol peaks was demonstrated in a mixed standard solution with overlapping (+)-catechin and (-)-epicatechin peaks and in commercial red wine with unknown impurities and confirming the reliability for polyphenol quantitation in red wine with matching migration time and current ratio.


Asunto(s)
Electroforesis Capilar , Flavonoides/análisis , Análisis de los Alimentos/métodos , Fenoles/análisis , Vino/análisis , Catequina/análisis , Catequina/aislamiento & purificación , Electroforesis Capilar/instrumentación , Electroforesis Capilar/métodos , Diseño de Equipo , Flavonoides/aislamiento & purificación , Ácido Gálico/análisis , Ácido Gálico/aislamiento & purificación , Modelos Lineales , Microelectrodos , Fenoles/aislamiento & purificación , Polifenoles , Reproducibilidad de los Resultados
15.
Electrophoresis ; 31(18): 3061-9, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20737465

RESUMEN

A PMMA microfluidic chip-CE device with a multi-segment circular-ferrofluid-driven micromixing injector has been developed for the determination of free bilirubin and its binding capacity by HSA at equilibrium. The design of the device and its fabrication by a low cost CO(2) laser are discussed for intended applications. Under optimized conditions, the total binding capacity of HSA for bilirubin was determined as 16.3±1.4 mg/l00 mL human serum (n=3) and residual binding capacity for bilirubin 9.8 mg/100 mL (n=3) in normal infants. To assess risk of hyperbilirubinemia, free bilirubin and residual binding capacity by HSA provide a better indicator than total bilirubin, as neonates with impaired bilirubin binding capacity could be detected. In addition, residual binding capacity provides an advanced indicator to predict the onset of hyperbilirubinemia before the appearance of free bilirubin. HSA down to 94 nL is used in each titration and a full assay of four titrations takes up 376 nL HSA, sufficient for newborns with HSA in microliter range. The device has shown capable to provide adequate margin of protection to detect an early rising level of bilirubin and impaired binding capacity prior to the onset of jaundice condition.


Asunto(s)
Bilirrubina/análisis , Electroforesis Capilar/instrumentación , Técnicas Analíticas Microfluídicas/instrumentación , Albúmina Sérica/metabolismo , Bilirrubina/sangre , Bilirrubina/metabolismo , Campos Electromagnéticos , Electroforesis Capilar/métodos , Óxido Ferrosoférrico/química , Humanos , Hiperbilirrubinemia/diagnóstico , Líquidos Iónicos/química , Láseres de Gas , Magnetismo , Técnicas Analíticas Microfluídicas/métodos , Polimetil Metacrilato/química , Unión Proteica
16.
Electrophoresis ; 31(18): 3044-52, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20872610

RESUMEN

To meet the need for onsite monitoring of urine anions, a microfluidic chip-capillary electrophoresis device was designed, fabricated and tested to extend the upper CE working range for an enhancement up to 500 fold (100 fold for sample dilution and 5 folds for CE injection) in order to analyze highly variable anionic metabolites in urine samples. Capillaries were embedded between two PMMA plates with laser-fabricated microchannel patterns to produce the microfluidic chip-capillary electrophoresis to perform standard/sample dilution and CE injection with adjustable dilution ratios. A circular ferrofluid valve was incorporated on-chip to perform cleanup and conditioning, mixing and dilution, injection and CE separation. Under optimized conditions, a complete assay for four samples can be achieved within an hour for 15 anions commonly found in urines. Satisfactory working ranges (0.005-500 mM) and low detection limits (0.5-6.5 µM based on S/N =2) are obtained with satisfactory repeatability (RSD, n=5) 0.52-0.87% and 4.1-6.5% for migration time and peak area, respectively. The working ranges with two orders adjustable upper extension are adequate to cover all analytes concentrations commonly found in human urine samples. The device fabricated shows sufficiently large experimentally verifiable enhancement factor to meet the application requirements. Its reliability was established by more than 94% recoveries of spiked standards and agreeable results from parallel method comparison with conventional ion chromatography method. The extension of the upper CE working range enables flexible onsite dilution on demand, a quick turn-around of results, and a low-cost device suitable for bedside monitoring of patients under critical conditions for metabolic disorders.


Asunto(s)
Aminoácidos/orina , Aniones/orina , Ácidos Carboxílicos/orina , Electroforesis por Microchip/instrumentación , Electroforesis por Microchip/métodos , Aminoácidos/química , Aniones/química , Biomarcadores/química , Biomarcadores/orina , Ácidos Carboxílicos/química , Diseño de Equipo , Humanos , Sensibilidad y Especificidad
17.
BMC Cell Biol ; 9: 52, 2008 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-18799018

RESUMEN

BACKGROUND: Human mesenchymal stromal cells (MSCs, also known as mesenchymal stem cells) are multipotent cells with potential therapeutic value. Owing to their osteogenic capability, MSCs may be clinically applied for facilitating osseointegration in dental implants or orthopedic repair of bony defect. However, whether wound infection or oral microflora may interfere with the growth and osteogenic differentiation of human MSCs remains unknown. This study investigated whether proliferation and osteogenic differentiation of MSCs would be affected by potent gram-positive and gram-negative derived bacterial toxins commonly found in human settings. RESULTS: We selected lipopolysaccharide (LPS) from Escherichia coli and lipoteichoic acid (LTA) from Streptococcus pyogenes as our toxins of choice. Our findings showed both LPS and LTA did not affect MSC proliferation, but prolonged LPS challenge upregulated the osteogenic differentiation of MSCs, as assessed by alkaline phosphatase activity and calcium deposition. Because toll-like receptors (TLRs), in particularly TLR4 and TLR2, are important for the cellular responsiveness to LPS and LTA respectively, we evaluated their expression profiles serially from MSCs to osteoblasts by quantitative PCR. We found that during osteogenic differentiation, MSC-derived osteoprogenitors gradually expressed TLR2 and TLR4 by Day 12. But under prolonged incubation with LPS, MSC-derived osteoprogenitors had reduced TLR2 and TLR4 gene expression. This peculiar response to LPS suggests a possible adaptive mechanism when MSCs are subjected to continuous exposure with bacteria. CONCLUSION: In conclusion, our findings support the potential of using human MSCs as a biological graft, even under a bacterial toxin-rich environment.


Asunto(s)
Toxinas Bacterianas/farmacología , Regulación hacia Abajo , Células Madre Mesenquimatosas/metabolismo , Osteoblastos/citología , Receptores Toll-Like/metabolismo , Diferenciación Celular , Células Cultivadas , Humanos , Lipopolisacáridos/química , Lipopolisacáridos/farmacología , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Osteogénesis/fisiología , Ácidos Teicoicos/química , Ácidos Teicoicos/farmacología , Receptor Toll-Like 2/metabolismo , Receptor Toll-Like 4/metabolismo
18.
Front Psychol ; 9: 2090, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30429816

RESUMEN

Online mindfulness-based intervention as a feasible and acceptable approach has received mounting attention in recent years, yet more evidence is needed to demonstrate its effectiveness. The primary objective of this study was to examine the effects of online mindfulness-based programs on psychological distress (depression and anxiety). The randomized controlled intervention design consisted of four conditions: group mindfulness-based intervention (GMBI), self-direct mindfulness-based intervention (SDMBI), discussion group (DG) and blank control group (BCG). The program lasted 8 weeks and a total of 76 participants completed the pre- and post-test. Results showed that participants in GMBI and SDMBI had significant pre- and post-test differences on mindfulness, emotion regulation difficulties, and psychological distress, with medium to large effect sizes. In addition, ANCOVA results indicated significant effects of group membership on post-test scores of mindfulness, depression and anxiety when controlling the pretest scores, with medium to large effect sizes. The GMBI appeared to exert the greatest effects on outcome variables in comparison with other groups. In addition, changes in emotion regulation difficulties across groups could mediate the relationship between changes in mindfulness dimensions (Observing and Describing) and changes in psychological distress across groups. These results provided encouraging evidence for the effectiveness of online mindfulness-based interventions in reducing psychological distress, and the possible mediating role of emotion regulation, while also underlining the importance of group discussion in online mindfulness-based interventions.

19.
Fam Cancer ; 17(1): 71-77, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28555354

RESUMEN

Lynch syndrome is an autosomal dominant condition caused by pathogenic mutations in the DNA mismatch repair (MMR) genes. Although commonly associated with clinical features such as intellectual disability and congenital anomalies, contiguous gene deletions may also result in cancer predisposition syndromes. We report on a 52-year-old male with Lynch syndrome caused by deletion of chromosome 2p16.3-p21. The patient had intellectual disability and presented with a prostatic adenocarcinoma with an incidentally identified synchronous sigmoid adenocarcinoma that exhibited deficient MMR with an absence of MSH2 and MSH6 protein expression. Family history was unrevealing. Physical exam revealed short stature, brachycephaly with a narrow forehead and short philtrum, brachydactyly of the hands, palmar transverse crease, broad and small feet with hyperpigmentation of the soles. The patient underwent total colectomy with ileorectal anastomosis for a pT3N1 sigmoid adenocarcinoma. Germline genetic testing of the MSH2, MSH6, and EPCAM genes revealed full gene deletions. SNP-array based DNA copy number analysis identified a deletion of 4.8 Mb at 2p16.3-p21. In addition to the three Lynch syndrome associated genes, the deleted chromosomal section encompassed genes including NRXN1, CRIPT, CALM2, FBXO11, LHCGR, MCFD2, TTC7A, EPAS1, PRKCE, and 15 others. Contiguous gene deletions have been described in other inherited cancer predisposition syndromes, such as Familial Adenomatous Polyposis. Our report and review of the literature suggests that contiguous gene deletion within the 2p16-p21 chromosomal region is a rare cause of Lynch syndrome, but presents with distinct phenotypic features, highlighting the need for recognition and awareness of this syndromic entity.


Asunto(s)
Cromosomas Humanos Par 2/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Eliminación de Gen , Discapacidad Intelectual/genética , Neoplasias Primarias Múltiples/genética , Adenocarcinoma/diagnóstico , Adenocarcinoma/genética , Adenocarcinoma/cirugía , Colectomía , Neoplasias Colorrectales Hereditarias sin Poliposis/diagnóstico , Pruebas Genéticas , Mutación de Línea Germinal , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Primarias Múltiples/diagnóstico , Neoplasias Primarias Múltiples/cirugía , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/genética , Neoplasias del Colon Sigmoide/diagnóstico , Neoplasias del Colon Sigmoide/genética , Neoplasias del Colon Sigmoide/cirugía
20.
PLoS One ; 11(6): e0156945, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27258094

RESUMEN

BACKGROUND: This study aims to assess evidence for any socioeconomic gradients in childhood obesity and hypertension in a population-representative sample in Hong Kong, China. METHODS: The data of a stratified random sampled growth survey collected in 2005-2006 was matched with a population by-census. Obesity was defined using the International Obesity Task Force standard and hypertension was defined using the Hong Kong norm table. Family socioeconomic status (SES) was measured by maternal education level. Neighbourhood SES was measured by median household income of the neighbourhood. Multilevel Poisson regression models with robust standard error were used to test the association. Body mass indices of children's parents were included as potential confounders. Intra-school/neighbourhood correlations were adjusted using random factors. RESULTS: Totally 14842 children (age 6-19 years) included in the analysis, in which 16.6% of them were overweight or obese. Children whose mother only completed secondary school or below had higher risk of childhood obesity (RR 1.41, 95% CI 1.13-1.76, p = 0.003) and hypertension (RR 1.18, 95% CI 1.01-1.36, p = 0.03). Meanwhile, children in the lowest neighbourhood SES group had higher risk of childhood underweight (RR 1.61, 95% CI 1.04-2.49, p = 0.03), overweight (RR 1.35, 95% CI 1.05-1.72, p = 0.02), and obesity (RR 2.07, 95% CI 1.11-3.88, p = 0.02). CONCLUSIONS: Socioeconomic gradient in childhood obesity and hypertension existed in Hong Kong, one of the most developed cities in China. These results have implications for policymakers and public health experts and highlight the need to monitor trends in other parts of China.


Asunto(s)
Hipertensión/epidemiología , Obesidad Infantil/epidemiología , Clase Social , Adolescente , Niño , China/epidemiología , Femenino , Hong Kong/epidemiología , Humanos , Hipertensión/etiología , Masculino , Sobrepeso/epidemiología , Sobrepeso/etiología , Obesidad Infantil/etiología , Prevalencia , Adulto Joven
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