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1.
J Exp Child Psychol ; 220: 105430, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35421627

RESUMEN

Children's everyday learning environment is semantically structured. For example, semantically related things (e.g., fork and spoon) usually co-occur in the same contexts. The current study examines the effects of semantically structured contexts on preschool-age children's (N = 65, 33 girls, age range: 52-68 months) use of statistical information to learn novel word-object mappings. Children were assigned into one of two conditions, in which objects from the same semantic category repeatedly co-occurred in the same trials (Same-category condition) or objects from different categories repeatedly co-occurred in the same trials (Different-categories condition). Children's word learning performance in the two conditions were comparable. However, their errors at test suggested that information extracted by children in the two conditions differed. Importantly, children in the Same-category condition extracted both statistical and semantic relationships from the stimuli.


Asunto(s)
Aprendizaje , Aprendizaje Verbal , Niño , Preescolar , Femenino , Humanos , Masculino , Extractos Vegetales , Instituciones Académicas , Semántica
2.
J Microbiol Immunol Infect ; 55(5): 803-811, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35283046

RESUMEN

PURPOSE: This study aimed to evaluate whether vitamin D supplementation can reduce the incidence of influenza and enterovirus infection in Taiwanese children. METHODS: This randomized, double-blind, controlled trial included children aged two to five years between April 2018 and October 2019 from daycare centers. All the participants were randomly assigned to a vitamin D supplementation group (2000 IU/day) or placebo group for one month. The primary outcome was the incidence of influenza and enterovirus infection in the following six months, and the secondary outcome was the incidence of influenza and enterovirus infection in the children's household members. RESULTS: Two hundred and forty-eight children participated. The vitamin D group showed a relative risk reduction of 84% against influenza compared to the placebo group but did not reach statistical significance. Kaplan-Meier curves revealed that the placebo group had a higher probability of influenza infection than the vitamin D group (log-rank test, p = 0.055), but the incidence of enterovirus infection was similar between the two groups (p = 0.946) among children. Among children's household members, the incidence of influenza (p = 0.586) and enterovirus infection (p = 0.528) were both similar between the two groups. All children who were tested for serum 25(OH)D levels after vitamin D intervention had 25(OH)D levels above 30 ng/ml CONCLUSION: Vitamin D supplementation may have a small preventative effect against influenza infection but does not affect enterovirus infection among preschool children. A high-dose short-term vitamin D intervention might be a way to elevate children's serum vitamin D levels in the first month of starting kindergarten.


Asunto(s)
Infecciones por Enterovirus , Gripe Humana , Preescolar , Humanos , Gripe Humana/epidemiología , Gripe Humana/prevención & control , Estaciones del Año , Suplementos Dietéticos , Vitamina D , Vitaminas , Método Doble Ciego , Infecciones por Enterovirus/epidemiología , Infecciones por Enterovirus/prevención & control
3.
ACS Appl Mater Interfaces ; 12(46): 51581-51588, 2020 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-33147003

RESUMEN

The absence of a high-performance p-channel oxide thin-film transistor (TFT) is the major challenge faced in the current oxide semiconductor device technology. Simple solution-based back-channel subgap defect termination using sulfur was developed for p-channel cuprous oxide (Cu2O)-TFTs. We investigated the origin of poor device characteristics in conventional Cu2O-TFTs and clarified that it was mainly because of a back-channel donor-like defect of ∼2.8 ×1013 cm-2 eV-1, which originated from the interstitial Cu defect. Sulfur ion treatment using thiourea effectively reduced the back-channel defect down to <3 × 1012 cm-2 eV-1 and demonstrated the Cu2O-TFT with a saturation mobility of 1.38 ± 0.7 cm2 V-1 s-1, a s-value of 2.35 ± 1.22 V decade-1, and an on/off current ratio of ∼4.1 × 106. The improvement of device characteristics was attributed to the reduction of back-channel defect by the formation of a thin CuSO4 back-channel passivation layer by the chemical reaction of interstitial Cu with S and O ions. An oxide-based complementary inverter using a p-channel Cu2O-TFT and a n-channel a-In-Ga-Zn-O-TFT was demonstrated with a high voltage gain of ∼230 at VDD = 70 V.

4.
Int J Mol Sci ; 21(8)2020 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-32326294

RESUMEN

Candida albicans (C. albicans) is an opportunistic human pathogen responsible for approximately a half of clinical candidemia. The emerging Candida spp. with resistance to azoles is a major challenge in clinic, suggesting an urgent demand for new drugs and therapeutic strategies. Alpha-enolase (Eno1) is a multifunctional protein and represents an important marker for invasive candidiasis. Thus, C. albicans Eno1 (CaEno1) is believed to be an important target for the development of therapeutic agents and antibody drugs. Recombinant CaEno1 (rCaEno1) was first used to immunize chickens. Subsequently, we used phage display technology to construct two single chain variable fragment (scFv) antibody libraries. A novel biopanning procedure was carried out to screen anti-rCaEno1 scFv antibodies, whose specificities were further characterized. The polyclonal IgY antibodies showed binding to rCaEno1 and native CaEno1. A dominant scFv (CaS1) and its properties were further characterized. CaS1 attenuated the growth of C. albicans and inhibited the binding of CaEno1 to plasminogen. Animal studies showed that CaS1 prolonged the survival rate of mice and zebrafish with candidiasis. The fungal burden in kidney and spleen, as well as level of inflammatory cytokines were significantly reduced in CaS1-treated mice. These results suggest CaS1 has potential of being immunotherapeutic drug against C. albicans infections.


Asunto(s)
Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Candida albicans/enzimología , Inhibidores Enzimáticos/farmacología , Fosfopiruvato Hidratasa/antagonistas & inhibidores , Anticuerpos de Cadena Única/farmacología , Animales , Evaluación Preclínica de Medicamentos , Ratones , Unión Proteica , Pez Cebra
5.
J Microbiol Immunol Infect ; 52(6): 880-887, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31732418

RESUMEN

BACKGROUND: Influenza is a major cause of acute respiratory infection burden worldwide, leading to many hospitalizations. An annual influenza vaccine is believed to be the best way to prevent influenza-related illnesses. We focused on the efficacies of other possible preventive measures such as increasing sun exposure time and dietary supplements to prevent these illnesses. METHODS: We conducted a matched-pair case-control study along with the Taiwan Pediatric Infectious Disease Alliance. We included influenza-related hospitalized patients with age ranging from 6 months to 5 years during the 2012-2013, 2013-2014, 2014-2015, and 2015-2016 influenza seasons. The controls were comparable to cases in age, sex, and residential area and had no influenza-related hospitalization records in the same season. We extracted data from vaccination histories and got the patients' guardians to complete questionnaires. Data were analyzed using conditional logistic regression. RESULTS: We enrolled 1514 children (421 influenza-infected cases and 1093 controls) in the study. We found seasonal influenza vaccination to be an independent protective factor against hospitalizations owing to influenza [p < 0.01; odds ratio (OR), 0.427; 95% confidence interval (CI), 0.306-0.594]. Children with mean sun exposure time of >7 h/week had a significantly lower risk of influenza-related hospitalizations than those with the mean sun exposure time of ≤7 h/week (p < 0.05; OR, 0.667; 95% CI, 0.491-0.906). CONCLUSIONS: Seasonal influenza vaccination effectively prevents influenza-related hospitalizations in children aged ≤5 years. Besides, >7 h of sun exposure/week may also be associated with lower risk of influenza-related hospitalizations in children.


Asunto(s)
Hospitalización/estadística & datos numéricos , Vacunas contra la Influenza/administración & dosificación , Gripe Humana/diagnóstico , Luz Solar , Estudios de Casos y Controles , Preescolar , Femenino , Humanos , Lactante , Gripe Humana/inmunología , Modelos Logísticos , Masculino , Oportunidad Relativa , Factores Protectores , Estaciones del Año , Taiwán , Vacunación/estadística & datos numéricos
6.
Nutrients ; 10(4)2018 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-29587438

RESUMEN

Influenza virus infection is a major global public health problem, and the efficacy of influenza vaccination is not satisfactory. Vitamin D is involved in many immune-mediated inflammatory processes. The impact of vitamin D levels on the immunogenic response to influenza vaccination is not clear. We performed a comprehensive literature search and systematic review of studies that investigated vitamin D and influenza vaccination. Data pertaining to study population, vaccine components, vitamin D levels, and immunogenic response were analyzed. Nine studies, with a combined study population of 2367 patients, were included in the systematic review. Four studies were included in the meta-analysis to investigate the influence of vitamin D deficiency (VDD) on the seroprotection (SP) rates and seroconversion (SC) rates following influenza vaccination. We found no significant association between vitamin D level and the immunogenic response to influenza vaccination. However, strain-specific differences may exist. We observed lower SP rates of influenza A virus subtype H3N2 (A/H3N2) and B strain in VDD patients than patients with normal vitamin D levels (A/H3N2: 71.8% vs. 80.1%, odds ratio (OR): 0.63, 95% confidence interval (CI): 0.43-0.91, p = 0.01; B strain: 69.6% vs. 76.4%, OR: 0.68, 95% CI: 0.5-0.93, p = 0.01). However, the SP rates of A/H1N1 and SC rates of all three strains were not significantly different in VDD and control groups. In conclusion, no association was observed between VDD and immunogenic response to influenza vaccination.


Asunto(s)
Alphainfluenzavirus/inmunología , Betainfluenzavirus/inmunología , Inmunogenicidad Vacunal , Vacunas contra la Influenza/administración & dosificación , Gripe Humana/prevención & control , Vacunación , Deficiencia de Vitamina D/inmunología , Adulto , Anciano , Biomarcadores/sangre , Distribución de Chi-Cuadrado , Niño , Preescolar , Femenino , Humanos , Vacunas contra la Influenza/efectos adversos , Vacunas contra la Influenza/inmunología , Gripe Humana/diagnóstico , Gripe Humana/inmunología , Gripe Humana/virología , Alphainfluenzavirus/patogenicidad , Betainfluenzavirus/patogenicidad , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Factores de Riesgo , Resultado del Tratamiento , Vacunación/efectos adversos , Vitamina D/análogos & derivados , Vitamina D/sangre , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/diagnóstico
7.
J Econ Entomol ; 111(1): 1-9, 2018 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-29281063

RESUMEN

Because life tables are capable of providing the most comprehensive description on the survival, stage differentiation, and the reproduction of animal populations, they can be considered as the bases of population ecology and pest management. Researchers concerned with studies involving life tables inevitably face the problem of describing the variabilities that occur in the survival, stage differentiation, and fecundity data. Finding a means to include these variabilities in population projections concerning pest management may be problematic. Henosepilachna vigintioctopunctata (F.) (Coleoptera: Coccinellidae) is a pest of many plant species in Asia, including cultivated crops, ornamentals, and wild plants. The raw life history data (survival, stage differentiation, and fecundity) and consumption rate of both sexes of H. vigintioctopunctata reared on Solanum photeinocarpum Nakamura et Odashima (Solanales: Solanaceae) were collected in the laboratory and analyzed based on the age-stage, two-sex life table theory. The intrinsic rate of increase (r), finite rate of increase (λ), net reproductive rate (R0), mean generation time (T), and net consumption rate (C0) of H. vigintioctopunctata were 0.1312 d-1, 1.1402 d-1, 603.5 offspring, 48.8 d, and 77.8 cm2, respectively. By using the bootstrap technique with 100,000 samples, we demonstrated that the life tables constructed based on the 2.5th and 97.5th percentiles of R0 and λ can be used to describe the variabilities found in the survival and fecundity curves and to project the uncertainty of population growth.


Asunto(s)
Escarabajos/fisiología , Dieta , Solanum/química , Animales , Escarabajos/crecimiento & desarrollo , Conducta Alimentaria , Femenino , Larva/crecimiento & desarrollo , Larva/fisiología , Tablas de Vida , Masculino , Modelos Biológicos , Crecimiento Demográfico , Pupa/crecimiento & desarrollo , Pupa/fisiología
8.
Ther Clin Risk Manag ; 13: 1205-1211, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29066901

RESUMEN

OBJECTIVES: Scabies is a common and annoying disorder. Pernicious anemia (PA) is a serious disease which, when untreated, leads to death. Mounting evidence suggests that immune-mediated inflammatory processes play a role in the pathophysiology of both diseases. The relationship between these two diseases has not been investigated. We conducted this study to explore the potential relationship between scabies and PA. MATERIALS AND METHODS: This nationwide, population-based study was conducted using the National Health Insurance Research Database of Taiwan. In total, 5,407 patients with scabies were identified as a study group and 20,089 matched patients were randomly selected as a control group. We tracked patients in both groups for a 7-year period to identify the incidence of PA. The demographic characteristics and comorbidities of the patients were analyzed, and Cox proportional hazards regression was used to calculate the hazard ratios for PA. RESULTS: Of the 25,496 patients in this study, 183 (0.7%) patients with newly diagnosed PA were identified during the 7-year follow-up period; 71 of 5,407 (1.3%) from the scabies group and 112 of 20,089 (0.6%) from the control group. Patients with scabies had a higher risk of subsequent PA, with a crude hazard ratio of 2.368. After adjusting for covariates, the adjusted hazard ratio was 1.51 (95% confidence interval: 1.09-2.08). CONCLUSION: This study demonstrated an increased risk of PA (adjusted hazard ratio 1.51) among patients with scabies. Immune-mediated inflammatory processes may contribute to this association. Further studies are warranted to investigate the entire pathological mechanisms between these two diseases. Physicians should pay attention to patients with history of scabies presented with anemia. Further confirmative tests of PA may contribute to correct diagnosis and initiation of vitamin B12 supplement.

9.
Medicine (Baltimore) ; 96(23): e7108, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28591057

RESUMEN

Scabies is a common and distressing disease caused by the mite Sarcoptes scabiei var. hominis. Psychiatric disorder in childhood is an important disease and easily neglected. There are several similarities in scabies and psychiatric disorders in childhood (PDC). Both of them may present with pruritus. They are relatively common in patients with lower socioeconomic status and crowded environment. Furthermore, immune-mediated inflammatory processes play a role in the pathophysiology in both diseases. An association between scabies and psychiatric disorders may exist. This nationwide population-based cohort study utilized data from the National Health Insurance Research Database to investigate the relationship between scabies and PDC. A total of 2137 children with scabies were identified as the study group and 8548 age- and sex-matched children were selected as the control group. A total of 607 (5.68%) children developed PDC during the 7-year follow-up period. The overall incidences of PDC are similar but patients with scabies had a higher risk of developing intellectual disability (ID) (scabies group vs control group: 1.3% vs 0.6%, adjusted hazard ratio: 2.04 and 95% confidence interval: 1.25-3.32). The immune-mediated inflammatory processes of both diseases were reviewed and may contribute to the 104% increased risk of interleukin in patients with scabies. We suggest a more comprehensive management in treating patients with scabies or ID. Early and comprehensive treatment of scabies and other risk factors may decrease the risk of subsequent ID. When we approach patients with ID, concurrent evaluation of scabies and other risk factors may contribute to successful management.


Asunto(s)
Discapacidad Intelectual/epidemiología , Escabiosis/epidemiología , Adolescente , Animales , Niño , Preescolar , Estudios de Cohortes , Comorbilidad , Bases de Datos Factuales , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Lactante , Recién Nacido , Discapacidad Intelectual/etiología , Discapacidad Intelectual/inmunología , Masculino , Programas Nacionales de Salud , Modelos de Riesgos Proporcionales , Riesgo , Sarcoptes scabiei , Escabiosis/complicaciones , Escabiosis/inmunología , Taiwán/epidemiología
10.
Cogn Sci ; 41(6): 1485-1509, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27671780

RESUMEN

Two experiments were conducted to examine adult learners' ability to extract multiple statistics in simultaneously presented visual and auditory input. Experiment 1 used a cross-situational learning paradigm to test whether English speakers were able to use co-occurrences to learn word-to-object mappings and concurrently form object categories based on the commonalities across training stimuli. Experiment 2 replicated the first experiment and further examined whether speakers of Mandarin, a language in which final syllables of object names are more predictive of category membership than English, were able to learn words and form object categories when trained with the same type of structures. The results indicate that both groups of learners successfully extracted multiple levels of co-occurrence and used them to learn words and object categories simultaneously. However, marked individual differences in performance were also found, suggesting possible interference and competition in processing the two concurrent streams of regularities.


Asunto(s)
Individualidad , Lenguaje , Aprendizaje/fisiología , Aprendizaje por Probabilidad , Estimulación Acústica , Formación de Concepto/fisiología , Femenino , Humanos , Masculino , Estimulación Luminosa , Adulto Joven
11.
J Agric Food Chem ; 64(46): 8848-8856, 2016 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-27934292

RESUMEN

Koji is made from grains fermented with Aspergillus oryzae and is essential for the production of many traditional Japanese foods. Many previous studies have shown that koji contributes to the improvement of dyslipidemia. However, little is known regarding the underlying mechanism of this effect. Furthermore, the compound contributing to the activation of lipid metabolism is unknown. We demonstrated that rice koji extract (RKE) induces the mRNA expression of peroxisome proliferator-activated receptor alpha (PPARα) target genes, which promotes lipid metabolism in murine hepatocytes. This effect was not observed in PPARα-KO hepatocytes. We also demonstrated that RKE contained linolenic acid (LIA), oleic acid (OA), and hydroxyoctadecadienoic acids (HODEs), which activate PPARα, using LC-MS analysis. Our findings suggest that RKE, containing LIA, OA, and HODEs, could be valuable in improving dyslipidemia via PPARα activation.


Asunto(s)
Aspergillus oryzae/metabolismo , Dislipidemias/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , Hígado/metabolismo , Oryza/microbiología , PPAR alfa/metabolismo , Extractos Vegetales/farmacología , Animales , Dislipidemias/tratamiento farmacológico , Dislipidemias/genética , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Humanos , Hígado/efectos de los fármacos , Ratones , Oryza/química , Oryza/metabolismo , PPAR alfa/genética , Extractos Vegetales/metabolismo
12.
Sci Rep ; 6: 27801, 2016 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-27302015

RESUMEN

Glyphosate is the number one herbicide in the world. We investigated the sub-lethal effects of this herbicide on the aphid Metopolophium dirhodum (Walker), using an age-stage, two-sex life table approach. Three concentrations of the herbicide (low - 33.5, medium - 66.9 and high - 133.8 mmol dm(-3) of active ingredient) and distilled water as the control were used. The LC50 of the IPA salt of glyphosate on M. dirhodum was equivalent to 174.9 mmol dm(-3) of the active ingredient (CI95: 153.0, 199.0). The population parameters were significantly negatively affected by herbicide application, and this negative effect was progressive with the increasing concentration of the herbicide. A difference of two orders of magnitude existed in the predicted population development of M. dirhodum between the high concentration of the herbicide and the control. This is the first study that comprehensively documents such a negative effect on the population of an herbivorous insect.


Asunto(s)
Áfidos/efectos de los fármacos , Áfidos/crecimiento & desarrollo , Glicina/análogos & derivados , Herbicidas/toxicidad , Estadios del Ciclo de Vida/efectos de los fármacos , Envejecimiento , Animales , Femenino , Fertilidad/efectos de los fármacos , Glicina/toxicidad , Reproducción/efectos de los fármacos , Rosa , Análisis de Supervivencia , Glifosato
13.
PLoS One ; 11(1): e0146692, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26745377

RESUMEN

The protective value of neuron-derived conditioned medium (NCM) in cerebral ischemia and the underlying mechanism(s) responsible for NCM-mediated brain protection against cerebral ischemia were investigated in the study. NCM was first collected from the neuronal culture growing under the in vitro ischemic condition (glucose-, oxygen- and serum-deprivation or GOSD) for 2, 4 or 6 h. Through the focal cerebral ischemia (bilateral CCAO/unilateral MCAO) animal model, we discovered that ischemia/reperfusion (I/R)-induced brain infarction was significantly reduced by NCM, given directly into the cistern magna at the end of 90 min of CCAO/MCAO. Immunoblocking and chemical blocking strategies were applied in the in vitro ischemic studies to show that NCM supplement could protect microglia, astrocytes and neurons from GOSD-induced cell death, in a growth factor (TGFß1, NT-3 and GDNF) and p-ERK dependent manner. Brain injection with TGFß1, NT3, GDNF and ERK agonist (DADS) alone or in combination, therefore also significantly decreased the infarct volume of ischemic brain. Moreover, NCM could inhibit ROS but stimulate IL-1ß release from GOSD-treated microglia and limit the infiltration of IL-ß-positive microglia into the core area of ischemic brain, revealing the anti-oxidant and anti-inflammatory activities of NCM. In overall, NCM-mediated brain protection against cerebral ischemia has been demonstrated for the first time in S.D. rats, due to its anti-apoptotic, anti-oxidant and potentially anti-glutamate activities (NCM-induced IL-1ß can inhibit the glutamate-mediated neurotoxicity) and restriction upon the infiltration of inflammatory microglia into the core area of ischemic brain. The therapeutic potentials of NCM, TGFß1, GDNF, NT-3 and DADS in the control of cerebral ischemia in human therefore have been suggested and require further investigation.


Asunto(s)
Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Neuronas/metabolismo , Fármacos Neuroprotectores/administración & dosificación , Daño por Reperfusión/prevención & control , Animales , Apoptosis , Encéfalo/irrigación sanguínea , Encéfalo/metabolismo , Encéfalo/patología , Movimiento Celular , Supervivencia Celular , Células Cultivadas , Medios de Cultivo Condicionados , Medio de Cultivo Libre de Suero , Evaluación Preclínica de Medicamentos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Factor Neurotrófico Derivado de la Línea Celular Glial/fisiología , Infarto de la Arteria Cerebral Media/metabolismo , Infarto de la Arteria Cerebral Media/patología , Masculino , Microglía/fisiología , Factores de Crecimiento Nervioso/fisiología , Estrés Oxidativo , Cultivo Primario de Células , Factores Protectores , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Factor de Crecimiento Transformador beta1/fisiología
14.
ACS Appl Mater Interfaces ; 5(16): 7831-7, 2013 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-23876031

RESUMEN

A spontaneously formed ZnO/ZnWOx bilayer resistive memory via an interfacial engineering by one-step sputtering process with controllable high resistance states was demonstrated. The detailed formation mechanism and microstructure of the ZnWOx layer was explored by X-ray photoemission spectroscopy (XPS) and transmission electron microscope in detail. The reduced trapping depths from 0.46 to 0.29 eV were found after formation of ZnWOx layer, resulting in an asymmetric I-V behavior. In particular, the reduction of compliance current significantly reduces the switching current to reach the stable operation of device, enabling less energy consumption. Furthermore, we demonstrated an excellent performance of the complementary resistive switching (CRS) based on the ZnO/ZnWOx bilayer structure with DC endurance >200 cycles for a possible application in three-dimensional multilayer stacking.


Asunto(s)
Nanoestructuras/química , Óxido de Zinc/química , Impedancia Eléctrica , Microscopía Electrónica de Transmisión , Nanotecnología , Tamaño de la Partícula
15.
ACS Nano ; 6(9): 8407-14, 2012 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-22900519

RESUMEN

We present a ZnO(1-x) nanorod array (NR)/ZnO thin film (TF) bilayer structure synthesized at a low temperature, exhibiting a uniquely rectifying characteristic as a homojunction diode and a resistive switching behavior as memory at different biases. The homojunction diode is due to asymmetric Schottky barriers at interfaces of the Pt/ZnO NRs and the ZnO TF/Pt, respectively. The ZnO(1-x) NRs/ZnO TF bilayer structure also shows an excellent resistive switching behavior, including a reduced operation power and enhanced performances resulting from supplements of confined oxygen vacancies by the ZnO(1-x) NRs for rupture and recovery of conducting filaments inside the ZnO TF layer. A hydrophobic behavior with a contact angle of ~125° can be found on the ZnO(1-x) NRs/ZnO TF bilayer structure, demonstrating a self-cleaning effect. Finally, a successful demonstration of complementary 1D1R configurations can be achieved by simply connecting two identical devices back to back in series, realizing the possibility of a low-temperature all-ZnO-based memory system.


Asunto(s)
Equipos de Almacenamiento de Computador , Electrónica/instrumentación , Membranas Artificiales , Nanoestructuras/química , Nanoestructuras/ultraestructura , Nanotecnología/instrumentación , Semiconductores , Óxido de Zinc/química , Cristalización/métodos , Impedancia Eléctrica , Electrodos , Diseño de Equipo , Análisis de Falla de Equipo , Tamaño de la Partícula
16.
Molecules ; 15(9): 6423-35, 2010 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-20877233

RESUMEN

The use of indigo naturalis to treat psoriasis has proved effective in our previous clinical studies. The present study was designed to examine the anti-inflammatory effect of indigo naturalis in primary cultured human umbilical vein endothelial cells (HUVECs). Pretreatment of cells with indigo naturalis extract attenuated TNF-α-induced increase in Jurkat T cell adhesion to HUVECs as well as decreased the protein and messenger (m)RNA expression levels of vascular cell adhesion molecule-1 (VCAM-1) on HUVECs. Indigo naturalis extract also inhibited the protein expression of activator protein-1 (AP-1)/c-Jun, a critical transcription factor for the activation of VCAM-1 gene expression. Since the reduction of lymphocyte adhesion to vascular cells by indigo naturalis extract could subsequently reduce the inflammatory reactions caused by lymphocyte infiltration in the epidermal layer and help to improve psoriasis, this study provides a potential mechanism for the anti-inflammatory therapeutic effect of indigo naturalis extract in psoriasis.


Asunto(s)
Células Endoteliales/efectos de los fármacos , Extractos Vegetales/farmacología , Plantas Medicinales/química , Factor de Necrosis Tumoral alfa/fisiología , Venas Umbilicales/citología , Molécula 1 de Adhesión Celular Vascular/análisis , Adhesión Celular/efectos de los fármacos , Humanos , Inflamación/tratamiento farmacológico , Células Jurkat/efectos de los fármacos , Células Jurkat/fisiología , Psoriasis/tratamiento farmacológico , ARN Mensajero/análisis , ARN Mensajero/efectos de los fármacos , Factor de Transcripción AP-1/antagonistas & inhibidores , Molécula 1 de Adhesión Celular Vascular/efectos de los fármacos , Molécula 1 de Adhesión Celular Vascular/genética
17.
Curr Top Med Chem ; 9(16): 1536-45, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19903164

RESUMEN

The chemical and biological diversity of the different marine evolutionary group is endless and therefore, this is an amazing resource for the discovery of new anticancer drugs. Comprising 34 of the 36 Phyla of life, marine ecosystems are indeed our last genetic diversity and biotechnological boundary; terrestrial systems possess only 17 Phyla. Sponges, coelenterates and microorganisms are the foremost resources of therapeutic compounds. Algae, echinoderms, tunicates, mollusks, bryozoans are also the sources of anticancer drugs from marine resources. We highlight the past and current status of marine anticancer pharmacology using different marine groups.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Descubrimiento de Drogas/tendencias , Animales , Antineoplásicos/uso terapéutico , Evaluación Preclínica de Medicamentos , Humanos , Océanos y Mares
18.
Curr Pharm Des ; 15(30): 3552-70, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19860700

RESUMEN

Recent progresses in the development of fluorescent technologies become a reliable device for drug discovery research. The fluorescence tools offer attractive options for an opportunity to visualize the effects of drug candidates in the cells. The fluorescent tools, such as fluorescent protein, are regularly used in a range of drug discovery processes. A better understanding and use of fluorescent technologies facilitate drug discovery research faster and can open up new applications. Therefore, we have provided information about some new generation fluorescent reagents (GFP and fluorophores). This review illustrates how fluorescent technologies and fluorescent tools are contributing to the drug discovery process mainly high-throughput screening (HTS), disease mechanism based target discovery, disease-genes-based target discovery, 'target classes' based target candidate discovery, physiology-based drug discovery, genomics-based drug discovery, target validation and their future perspectives.


Asunto(s)
Descubrimiento de Drogas , Fluorescencia , Animales , Evaluación Preclínica de Medicamentos/instrumentación , Colorantes Fluorescentes , Genética , Genómica , Proteínas Fluorescentes Verdes , Humanos , Receptores de Droga/efectos de los fármacos
19.
Curr Drug Metab ; 10(2): 116-24, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19275547

RESUMEN

In last few years, the use of zebrafish (Danio rerio) in scientific research is growing very rapidly. Initially, it was a popular as a model of vertebrate development because zebrafish embryos are transparent and also develop rapidly. Presently, the research using zebrafish is expanding into other areas such as pharmacology, clinical research as a diseases model and interestingly in drug discovery. The use of zebrafish in pharmaceutical research and discovery and drug development is mainly screening of lead compounds, target identification, target validation, morpholino oligonucleotide screens, assay development for drug discovery, physiology based drug discovery, quantitative structure-activity relationship (QSAR) and structure -activity relationships (SAR) study and drug toxicity study. In this paper, we have described properly all the areas of drug discovery where zebrafish is used as a tool. We are hopeful that the use of these techniques or methods will make the zebrafish a prominent model in drug discovery and development research in the forthcoming years.


Asunto(s)
Diseño de Fármacos , Evaluación Preclínica de Medicamentos/métodos , Modelos Animales , Animales , Modelos Animales de Enfermedad , Sistemas de Liberación de Medicamentos , Descubrimiento de Drogas/métodos , Relación Estructura-Actividad Cuantitativa , Pruebas de Toxicidad/métodos , Pez Cebra
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