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1.
J Clin Pharm Ther ; 42(3): 318-328, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28370404

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: Pharmacy claims are commonly used to assess medication adherence. It is unclear how different approaches to handling hospitalizations compare to the gold standard of using outpatient and inpatient drug data. This study aimed to compare the impact of different approaches to handling hospitalizations on medication adherence estimation in administrative claims data. METHODS: We identified ß-blocker initiators after myocardial infarction (MI) and statin initiators regardless of hospitalization histories in the population-based, Taiwan database, which includes outpatient and inpatient drug claims data. Adherence to ß-blockers or to statins during a 365-day follow-up period was estimated in outpatient pharmacy claims using the proportion of days covered (PDC) in three ways: ignoring hospitalizations (PDC1); subtracting hospitalized days from the denominator (PDC2); and assuming drug use on all hospitalized days (PDC3). We compared these to an approach that incorporated inpatient drug use (PDC4). We also used a hypothetical example to examine variations across approaches in several scenarios, such as increasing hospitalized days. RESULTS AND DISCUSSION: Mean 365-day PDC was 74% among 1729 post-MI ß-blocker initiators (range: 73.1%-74.9%) and 44% among 69 435 statins initiators (range: 43.5%-44.0%), which varied little across approaches. Differences across approaches increased with increasing number of hospitalized days. For patients hospitalized for >28 days, mean difference across approaches was >15%. PDC3 consistently yielded the highest value and PDC1 the lowest. WHAT IS NEW AND CONCLUSIONS: On average, different approaches to handling hospitalizations lead to similar adherence estimates to the gold standard of incorporating inpatient drug use. When patients have many hospitalization days during follow-up, the choice of approach should be tailored to the specific setting.


Asunto(s)
Antagonistas Adrenérgicos beta/administración & dosificación , Hospitalización/estadística & datos numéricos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Cumplimiento de la Medicación/estadística & datos numéricos , Antagonistas Adrenérgicos beta/uso terapéutico , Anciano , Bases de Datos Factuales/estadística & datos numéricos , Femenino , Estudios de Seguimiento , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Pacientes Internos/estadística & datos numéricos , Seguro de Servicios Farmacéuticos/estadística & datos numéricos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/tratamiento farmacológico , Pacientes Ambulatorios/estadística & datos numéricos , Taiwán
2.
Clin Exp Dermatol ; 41(4): 341-5, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26566758

RESUMEN

BACKGROUND: A growing body of evidence has shown that microRNA-29 (miR-29) plays a central role in the progression of fibrosis. However, the mechanisms underlying the role of miR-29 in keloid fibrogenesis remain unknown. AIM: To investigate the roles of miR-29 in dermal fibroblasts in the pathogenesis of keloids. METHODS: Primary fibroblasts from 9 patients with keloid and 6 healthy controls (HCs) were cultured and pretreated with transforming growth factor (TGF)-ß1. Next, fibroblasts were transfected with precursor miRNA and anti-miR-29a miRNA. TGF-ß1-associated miR-29 alterations were investigated by quantitative real-time PCR. Collagen I and collagen III protein levels were analysed by western blotting. RESULTS: miR-29a, miR-29b and miR-29c levels were significantly lower in keloid compared with healthy fibroblasts (P < 0.05), and in particular, miR-29a was especially markedly reduced (P < 0.001). Type I and type III collagen mRNA and protein levels were decreased in keloid fibroblasts transfected with pre-miR-29a (P < 0.05), whereas knockdown with anti-miR-29a increased type I and type III collagen mRNA and protein expression (P < 0.05) in the fibroblasts. Interestingly, pretreatment of fibroblasts with TGF-ß1 significantly decreased miR-29a (P < 0.05), whereas miR-29b and miR-29c were reduced to a lesser extent, which was not significant. CONCLUSIONS: These findings show that miR-29a exerts as a novel regulator in the fibrogenesis of keloid, suggesting that miR-29a might be a novel marker for keloid.


Asunto(s)
Queloide/etiología , Queloide/genética , MicroARNs/genética , Adolescente , Adulto , Colágeno Tipo I/metabolismo , Colágeno Tipo III/metabolismo , Femenino , Fibroblastos/metabolismo , Humanos , Masculino , Factor de Crecimiento Transformador beta1/genética
3.
Clin Exp Dermatol ; 41(2): 152-5, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26121920

RESUMEN

Evidence has suggested that vascular endothelial growth factor (VEGF), a crucial growth factor in regulating endothelial progenitor cells (EPCs), plays a central role in keloid formation. However, the levels of circulating EPCs in patients with keloid have not yet been explored. The aim of this study was to determine the number of circulating EPCs in patients with keloid. Circulating EPCs (defined as CD45- CD34+CD133+VEGFR2+cells) and VEGF levels from 39 patients with keloid and 22 healthy controls (HCs) were assessed by flow cytometry and ELISA, respectively. EPCs were detectable in the peripheral blood of patients with keloid. The number of circulating EPCs and the levels of plasma VEGF were significantly higher in patients with keloid than in HCs. However, no correlation was found between the number of circulating EPCs and the serum VEGF levels. This study provides the first evidence that EPCs are increased in the peripheral blood of patients with keloid. Understanding the roles of EPCs in keloid fromation may lead to the development of novel therapeutic strategies for keloid.


Asunto(s)
Células Progenitoras Endoteliales/citología , Queloide/sangre , Adolescente , Adulto , Estudios de Casos y Controles , Niño , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Humanos , Queloide/metabolismo , Queloide/patología , Masculino , Persona de Mediana Edad , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Adulto Joven
4.
Genet Mol Res ; 15(3)2016 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-27706598

RESUMEN

Development of the eyelid requires coordination of the cellular processes involved in proliferation, cell size alteration, migration, and cell death. C57BL/6J-corneal opacity (B6-Co) mice are mutant mice generated by the administration of N-ethyl-N-nitrosourea (100 mg/kg). They exhibit the eyelids open at birth phenotype, abnormal round cell shape from tightened F-actin bundles in leading edge keratinocytes at E16.5, and gradual corneal opacity with neovessels. The tip of the leading edge in B6-Co mice did not move forward, and demonstrated a sharp peak shape without obvious directionality. Analysis of the biological characteristics of B6-Co mice demonstrated that abnormal migration of keratinocytes could affect eyelid development, but proliferation and apoptosis in B6-Co mice had no effect. Mutant gene mapping and sequence analysis demonstrated that in B6-Co mice, adenosine was inserted into the untranslated regions, between 3030 and 3031, in the mRNA 3'-terminal of Fgf10. In addition, guanine 7112 was substituted by adenine in the Mtap1B mRNA, and an A2333T mutation was identified in Mtap1B. Quantitative real-time polymerase chain reaction analysis showed that expression of the Hbegf gene was significantly down-regulated in the eyelids of B6- Co mice at E16.5, compared to B6 mice. However, the expression of Rock1, Map3k1, and Jnk1 genes did not show any significant changes. Abnormal keratinocyte migration and down-regulated expression of the Hbegf gene might be associated with impaired eyelid development in B6-Co mice.


Asunto(s)
Córnea/metabolismo , Neovascularización de la Córnea/genética , Opacidad de la Córnea/genética , Párpados/metabolismo , Factor de Crecimiento Similar a EGF de Unión a Heparina/genética , Queratinocitos/metabolismo , Regiones no Traducidas 3' , Actinas/genética , Actinas/metabolismo , Animales , Movimiento Celular , Polaridad Celular , Proliferación Celular , Forma de la Célula , Córnea/anomalías , Córnea/crecimiento & desarrollo , Neovascularización de la Córnea/inducido químicamente , Neovascularización de la Córnea/metabolismo , Neovascularización de la Córnea/patología , Opacidad de la Córnea/inducido químicamente , Opacidad de la Córnea/metabolismo , Opacidad de la Córnea/patología , Embrión de Mamíferos , Etilnitrosourea , Párpados/anomalías , Párpados/crecimiento & desarrollo , Factor 10 de Crecimiento de Fibroblastos/genética , Factor 10 de Crecimiento de Fibroblastos/metabolismo , Regulación del Desarrollo de la Expresión Génica , Factor de Crecimiento Similar a EGF de Unión a Heparina/metabolismo , Queratinocitos/patología , Ratones , Ratones Endogámicos C57BL , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Mutágenos , Fenotipo , Cultivo Primario de Células
5.
Phys Chem Chem Phys ; 17(21): 14177-84, 2015 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-25959566

RESUMEN

The compound trans-4,4'-azo-1,2,4-triazole (atrz) is a planar molecule with two planar triazole rings bridged by an azo group. The molecule is a good donor ligand and has an interesting π-delocalized character. In addition, intermolecular interactions in the crystalline state through π-π stacking are found between triazole rings with a very short inter-planar distance of 3.17 Å. The electron density distribution is obtained from both high resolution X-ray diffraction data at 100 K and density functional theory (DFT) calculations using the ωB97X-D functional. Bond characterization is performed in terms of the charge density distribution and the associated topological properties. The Laplacian distribution around each atom reveals the shape of the valence-shell charge concentration and demonstrates a sp(2) hybrid orbital shape for each atom in the molecule. The π-delocalization of the planar molecule is further illustrated by the Fermi-hole distribution. The weak intermolecular π-π interactions and hydrogen bonds are further illustrated by the Hirshfeld surface. The energies of weak intermolecular π-π interactions and hydrogen bonds have been calculated using ωB97X-D/6-311++G(3df,2p) at experimental geometry.

6.
J Eur Acad Dermatol Venereol ; 29(8): 1570-5, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25545122

RESUMEN

BACKGROUND: Lichen planus (LP) is a chronic inflammatory disorder with unknown aetiology. The association between LP and various autoimmune diseases has been reported, but nationwide study of the relationship of LP with associated diseases is quite limited. OBJECTIVE: Our study aims to clarify the association between LP and a variety of autoimmune diseases in Taiwanese. METHODS: Data were obtained from the National Health Insurance Research Database (NHIRD) of Taiwan from 1997 to 2011. In total, 12,427 patients with LP and 49,708 age- and gender-matched controls were enrolled. RESULTS: Among patients with LP, there were significant associations with systemic lupus erythematosus (SLE) (multivariate odds ratio [mOR]: 2.87; 95% CI: 1.97-4.17), Sjögren's syndrome (mOR: 3.75; 95% CI: 2.66-5.28), dermatomyositis (mOR: 6.34; 95% CI: 1.82-22.16), vitiligo (mOR: 2.09; 95% CI: 1.31-3.32) and alopecia areata (mOR: 2.82; 95% CI: 2.20-3.62). On gender-stratified analyses, SLE and alopecia areata were significantly associated with LP in both genders. The association with Sjögren's syndrome was significant only in female patients. The associations with dermatomyositis and vitiligo became insignificant in both genders. CONCLUSION: Lichen planus is associated with various autoimmune diseases. Further study is required to elucidate the possible underlying mechanisms and roles of autoimmunity in the aetiology of LP.


Asunto(s)
Enfermedades Autoinmunes/complicaciones , Liquen Plano/complicaciones , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Taiwán
7.
Colorectal Dis ; 16(4): 259-64, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24118729

RESUMEN

AIM: High-risk patients with Stage II colon cancer may benefit from adjuvant chemotherapy, but it is difficult to identify such a patient group. A robust and reproducible index would be helpful to select the subset of Stage II colon cancer patients at high risk. This study investigated the potential prognostic significance of tumour budding in Stage II colon cancer. METHOD: In all, 135 Stage II colon cancer patients with known outcome were identified. The degree of tumour budding was assessed by two individual observers and was classified, according to the number of tumour buds in the area with the greatest budding intensity on haematoxylin and eosin slides, as high-grade budding (10 or more tumour buds) and low-grade budding (0-9 buds). Inter-observer agreement for two observers was assessed by using the kappa test. Progression-free and cancer-specific survivals were analysed using the Kaplan-Meier method and Cox regression. RESULTS: The 5-year progression-free survival rates for patients with high-grade tumour budding (n = 36) and those with low-grade budding (n = 99) were 57.6% and 89.0% (P < 0.001). The 5-year cancer-specific survival rates were 66.7% vs 92.0% (P < 0.001). Cox regression analyses demonstrated tumour budding as an independent predictor of disease progression (hazard ratio 4.982, P < 0.001) and cancer-related death (hazard ratio 4.142, P = 0.003). The two observers agreed on the classification of tumour budding in 118 cases (87.4%) and the inter-observer agreement was good (κ = 0.692). CONCLUSION: Tumour budding is a strong and reproducible prognostic factor for adverse outcome in Stage II colon cancer, which may serve as a prognostic marker to identify patients with a high risk of recurrence who may benefit from adjuvant therapy.


Asunto(s)
Carcinoma/patología , Neoplasias del Colon/patología , Recurrencia Local de Neoplasia/patología , Medición de Riesgo , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Adulto Joven
8.
Nat Genet ; 14(4): 430-40, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8944023

RESUMEN

The hereditary breast and ovarian cancer gene, BRCA1, encodes a large polypeptide that contains the cysteine-rich RING motif, a zinc-binding domain found in a variety of regulatory proteins. Here we describe a novel protein that interacts in vivo with the N-terminal region of BRCA1. This BRCA1-associated RING domain (BARD1) protein contains an N-terminal RING motif, three tandem ankyrin repeats, and a C-terminal sequence with significant homology to the phylogenetically conserved BRCT domains that lie near the C terminus of BRCA1. The BARD1/BRCA1 interaction is disrupted by BRCA1 missense mutations that segregate with breast cancer susceptibility, indicating that BARD1 may be involved in mediating tumour suppression by BRCA1.


Asunto(s)
Proteína BRCA1/metabolismo , Proteínas Portadoras/metabolismo , Proteínas Supresoras de Tumor , Ubiquitina-Proteína Ligasas , Secuencia de Aminoácidos , Ancirinas/metabolismo , Proteína BRCA1/genética , Sitios de Unión , Neoplasias de la Mama/metabolismo , Proteínas Portadoras/genética , Línea Celular , Escherichia coli/genética , Femenino , Células HeLa , Humanos , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Neoplasias Ováricas/metabolismo , Unión Proteica , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Saccharomyces cerevisiae/genética , Homología de Secuencia de Aminoácido , Células Tumorales Cultivadas
9.
Int J Clin Pract ; 66(1): 21-7, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22171902

RESUMEN

The high risk of recurrence in post-operative hepatocellular carcinoma (HCC) highlights the need for an effective adjuvant treatment. A systematic review of randomised controlled trials (RCTs) was performed to evaluate the clinical efficacy of adjuvant adoptive immunotherapy (AIT) for post-operative HCC patients. Electronic (MEDLINE, EMBASE and Cochrane Library databases) and manual searches were conducted throughout May 2011 to identify RCTs evaluating postoperative AIT for patients with HCC. Methodological quality was assessed in accordance with the QUOROM statement. Four RCTs totalling 423 patients met the eligibility criteria. All RCTs reported significantly improved disease-free survival rate or reduced recurrence rate after treating with adjuvant AIT (p < 0.05). The overall survival rates of AIT group are slightly higher than those of the control group in one study. Moreover, AIT was a safe treatment, with fever as the main adverse effects. This study adds to the evidence that postoperative HCC patients treated with adjuvant AIT show an improvement in disease-free survival rate or recurrence rate.


Asunto(s)
Carcinoma Hepatocelular/terapia , Inmunoterapia Adoptiva/métodos , Neoplasias Hepáticas/terapia , Adyuvantes Inmunológicos/uso terapéutico , Carcinoma Hepatocelular/cirugía , Supervivencia sin Enfermedad , Humanos , Inmunoterapia Adoptiva/efectos adversos , Neoplasias Hepáticas/cirugía , Recurrencia Local de Neoplasia/prevención & control , Cuidados Posoperatorios/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
10.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(5): 918-922, 2021 May 10.
Artículo en Zh | MEDLINE | ID: mdl-34814489

RESUMEN

In medical research, the quality of data is the key to success. Thus, data quality control becomes an important part of ensuring the research's high quality. REDCap system is an emerging data acquisition system in medical research, which is gradually applied in research at home and abroad. It is a hot issue to realize double data entry and data quality control in using the REDCap system, which researchers are concerned about when this system is supposed to apply. This article will systematically introduce how to use the REDCap system for double data entry and quality control from the aspects of research project creation, data collection tool design, double data entry, data checking and exporting.


Asunto(s)
Investigación Biomédica , Proyectos de Investigación , Recolección de Datos , Humanos , Control de Calidad
11.
Theor Appl Genet ; 121(5): 951-9, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20526576

RESUMEN

A major limiting factor for high productivity of maize (Zea mays L.) in dense planting is light penetration through the canopy. Plant architecture with a narrower leaf angle (LA) and an optimum leaf orientation value (LOV) is desirable to increase light capture for photosynthesis and production per unit area. However, the genetic control of the plant architecture traits remains poorly understood in maize. In this study, QTL for LA, LOV, and related traits were mapped using a set of 229 F(2:3) families derived from the cross between compact and expanded inbred lines, evaluated in three environments. Twenty-five QTL were detected in total. Three of the QTL explained 37.4% and five of the QTL explained 53.9% of the phenotypic variance for LA and LOV, respectively. Two key genome regions controlling leaf angle and leaf orientation were identified. qLA1 and qLOV1 at nearest marker umc2226 on chromosome 1.02 accounted for 20.4 and 23.2% of the phenotypic variance, respectively; qLA5 and qLOV5 at nearest bnlg1287 on chromosome 5 accounted for 9.7 and 9.8% of the phenotypic variance, respectively. These QTL could provide useful information for marker-assisted selection in improving performance of plant architecture with regard to leaf angle and orientation.


Asunto(s)
Mapeo Cromosómico , Hojas de la Planta/anatomía & histología , Hojas de la Planta/genética , Sitios de Carácter Cuantitativo/genética , Zea mays/anatomía & histología , Zea mays/genética , Agricultura , Cruzamientos Genéticos , Ligamiento Genético , Repeticiones de Microsatélite/genética , Carácter Cuantitativo Heredable
12.
Science ; 293(5529): 510-4, 2001 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-11441146

RESUMEN

Clock:BMAL1 and NPAS2:BMAL1 are heterodimeric transcription factors that control gene expression as a function of the light-dark cycle. Although built to fluctuate at or near a 24-hour cycle, the clock can be entrained by light, activity, or food. Here we show that the DNA-binding activity of the Clock:BMAL1 and NPAS2:BMAL1 heterodimers is regulated by the redox state of nicotinamide adenine dinucleotide (NAD) cofactors in a purified system. The reduced forms of the redox cofactors, NAD(H) and NADP(H), strongly enhance DNA binding of the Clock:BMAL1 and NPAS2:BMAL1 heterodimers, whereas the oxidized forms inhibit. These observations raise the possibility that food, neuronal activity, or both may entrain the circadian clock by direct modulation of cellular redox state.


Asunto(s)
Proteínas de Unión al ADN , ADN/metabolismo , NADP/metabolismo , NAD/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Receptores de Hidrocarburo de Aril , Transactivadores/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción ARNTL , Animales , Translocador Nuclear del Receptor de Aril Hidrocarburo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Relojes Biológicos , Proteínas CLOCK , Línea Celular , Ritmo Circadiano , Dimerización , Secuencias Hélice-Asa-Hélice , Humanos , L-Lactato Deshidrogenasa/genética , L-Lactato Deshidrogenasa/metabolismo , Ratones , NAD/farmacología , NADP/farmacología , Proteínas del Tejido Nervioso/química , Oxidación-Reducción , Proteínas Recombinantes/metabolismo , Transactivadores/química , Factores de Transcripción/química
13.
Clin Exp Dermatol ; 34(8): e907-9, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20055864

RESUMEN

Aquagenic syringeal acrokeratoderma (ASA) is a rare acquired disorder that develops predominantly in young women. It is clinically characterized by a burning sensation and whitish discolouration on the hands and rarely on the soles after brief immersion in water, which resolves within a short time after drying. Topical aluminium chloride and salicylic acid are reportedly beneficial in some cases. In total, 20 female and 8 male patients with ASA have been reported previously. We present another male patient, who failed to respond to treatment with antihistamines and topical steroids, but responded well to formalin 3% in alcohol without any side-effects.


Asunto(s)
Formaldehído/administración & dosificación , Hiperhidrosis/patología , Inmersión/efectos adversos , Queratodermia Palmoplantar/patología , Adulto , Humanos , Hiperhidrosis/complicaciones , Hiperhidrosis/tratamiento farmacológico , Queratodermia Palmoplantar/tratamiento farmacológico , Queratodermia Palmoplantar/etiología , Masculino , Agua
14.
Water Environ Res ; 81(7): 687-94, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19691249

RESUMEN

The objective of this study was to evaluate the feasibility of using ferrous ion-activated persulfate oxidation to remediate groundwater contaminated with methyl tert-butyl ether (MTBE). In this study, batch experiments were conducted to evaluate the effects of various factors on the efficiency of MTBE degradation including persulfate concentrations, ferrous ion concentrations, and persulfate coupled with hydrogen peroxide. Results show that ferrous ion-activated persulfate oxidation was capable of degrading MTBE efficiently. Persulfate and ferrous ion concentrations correlated with MTBE degradation rates. However, excess addition of ferrous ion resulted in decreased MTBE degrading rates most likely because of competition for sulfate free radicals between ferrous ion and MTBE. Two main byproducts of MTBE degradation, tert-butyl formate and tert-butyl alcohol, were detected in the experiments; both were, however, subsequently degraded. Results of sulfate analysis show that proper addition of ferrous ion could prevent unnecessary persulfate decomposition.


Asunto(s)
Contaminantes Atmosféricos/química , Compuestos Ferrosos/química , Éteres Metílicos/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Formiatos/química , Iones , Cinética , Oxidación-Reducción , Alcohol terc-Butílico/química
15.
AJNR Am J Neuroradiol ; 40(2): 206-212, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30655254

RESUMEN

Magnetic particle imaging is an emerging tomographic technique with the potential for simultaneous high-resolution, high-sensitivity, and real-time imaging. Magnetic particle imaging is based on the unique behavior of superparamagnetic iron oxide nanoparticles modeled by the Langevin theory, with the ability to track and quantify nanoparticle concentrations without tissue background noise. It is a promising new imaging technique for multiple applications, including vascular and perfusion imaging, oncology imaging, cell tracking, inflammation imaging, and trauma imaging. In particular, many neuroimaging applications may be enabled and enhanced with magnetic particle imaging. In this review, we will provide an overview of magnetic particle imaging principles and implementation, current applications, promising neuroimaging applications, and practical considerations.


Asunto(s)
Fenómenos Magnéticos , Neuroimagen/métodos , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Nanopartículas
16.
J Clin Invest ; 94(6): 2231-6, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7527428

RESUMEN

Nitric oxide (NO) is an important mediator of physiologic and inflammatory processes in the lung. To better understand the role of NO in the airway, we examined constitutive NO synthase (NOS) gene expression and function in NCI-H441 human bronchiolar epithelial cells, which are believed to be of Clara cell lineage. NOS activity was detected by [3H]arginine to [3H]citrulline conversion (1,070 +/- 260 fmol/mg protein per minute); enzyme activity was inhibited 91% by EGTA, consistent with the expression of a calcium-dependent NOS isoform. Immunoblot analyses with antisera directed against neuronal, inducible, or endothelial NOS revealed expression solely of endothelial NOS protein. Immunocytochemistry for endothelial NOS revealed staining predominantly in the cell periphery, consistent with the association of this isoform with the cellular membrane. To definitively identify the NOS isoform expressed in H441 cells, NOS cDNA was obtained by degenerate PCR. Sequencing of the H441 NOS cDNA revealed 100% identity with human endothelial NOS at the amino acid level. Furthermore, the H441 NOS cDNA hybridized to a single 4.7-kb mRNA species in poly(A)+ RNA isolated from H441 cells, from rat, sheep, and pig lung, and from ovine endothelial cells, coinciding with the predicted size of 4.7 kb for endothelial NOS mRNA. Guanylyl cyclase activity in H441 cells, assessed by measuring cGMP accumulation, rose 6.6- and 5.4-fold with calcium-mediated activation of NOS by thapsigargin and A23187, respectively. These findings indicate that endothelial NOS is expressed in select bronchiolar epithelial cells, where it may have autocrine effects through activation of guanylyl cyclase. Based on these observations and the previous identification of endothelial NOS in a kidney epithelial cell line, it is postulated that endothelial NOS may be expressed in unique subsets of epithelial cells in a variety of organs, serving to modulate ion flux and/or secretory function.


Asunto(s)
Aminoácido Oxidorreductasas/biosíntesis , Bronquios/enzimología , Isoenzimas/biosíntesis , Aminoácido Oxidorreductasas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Bronquios/patología , Clonación Molecular , Endotelio Vascular/enzimología , Epitelio/enzimología , Epitelio/patología , Guanilato Ciclasa/análisis , Humanos , Immunoblotting , Inmunohistoquímica , Isoenzimas/genética , Datos de Secuencia Molecular , Óxido Nítrico Sintasa , Reacción en Cadena de la Polimerasa , Ratas , Ovinos , Especificidad de la Especie , Células Tumorales Cultivadas
17.
Nucleic Acids Res ; 29(16): 3335-46, 2001 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-11504871

RESUMEN

The mts1/S100A4 gene encodes a small acidic calcium-binding protein that is expressed in a cell-specific manner in development, tumorigenesis and certain tissues of adult mice. A composite enhancer that is active in murine mammary adenocarcinoma cells was previously identified in the first intron of the mts1/S100A4 gene. Here we present a detailed analysis of the structure and function of this enhancer in the Mts1/S100A4-expressing CSML100 and non-expressing CSML0 mouse adenocarcinoma cell lines. In CSML100 cells the enhancer activity is composed of at least six cis-elements interacting with Sp1 and AP-1 family members and CBF/AML/PEBP2 and KRC transcription factors. In addition, a minisatellite-like DNA sequence significantly contributes to the enhancer activity via interaction with abundant proteins, which likely have been described previously under the name minisatellite-binding proteins. Extensive mutational analysis of the mts1/S100A4 enhancer revealed a cooperative function of KRC and the factors binding minisatellite DNA. This is the first example of an enhancer where two nuclear factors earlier implicated in different recombination processes cooperate to activate transcription. In Mts1/S100A4-negative CSML0 cells the strength of the enhancer was 7- to 12.5-fold lower compared to that in CSML100 cells, when referred to the activities of three viral promoters. In CSML0 cells the enhancer could be activated by exogenous AP-1 and CBF transcription factors.


Asunto(s)
Elementos de Facilitación Genéticos/genética , Genes p16/genética , Intrones/genética , Repeticiones de Minisatélite/genética , Metástasis de la Neoplasia/genética , Elementos de Respuesta/genética , Factores de Transcripción/metabolismo , Sitio Alostérico , Animales , Secuencia de Bases , Proteína de Unión a CREB , ADN/genética , ADN/metabolismo , Huella de ADN , Proteínas de Unión al ADN/metabolismo , Regulación Neoplásica de la Expresión Génica , Genes Virales/genética , Ratones , Datos de Secuencia Molecular , Mutación/genética , Proteínas Nucleares/metabolismo , Especificidad de Órganos , Regiones Promotoras Genéticas/genética , Factor de Transcripción Sp1/metabolismo , Transactivadores/metabolismo , Factor de Transcripción AP-1/metabolismo , Células Tumorales Cultivadas
18.
Cancer Res ; 61(21): 7943-9, 2001 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11691816

RESUMEN

A cDNA clone encoding human SRBC [serum deprivation response factor (sdr)-related gene product that binds to c-kinase] was isolated in a yeast two-hybrid screening, with amino acids 1-304 of BRCA1 as the probe. The human SRBC gene (hSRBC) was mapped to chromosome region 11p15.5-p15.4, close to marker D11S1323, at which frequent loss of heterozygosity (LOH) has been observed in sporadic breast, lung, ovarian, and other types of adult cancers as well as childhood tumors. hSRBC-coding region mutations including frame shift and truncation mutations were detected in a few ovarian and lung cancer cell lines. More significantly, the expression of hSRBC protein was down-regulated in a large fraction [30 (70%) of 43] of breast, lung, and ovarian cancer cell lines, whereas strong expression of hSRBC protein was detected in normal mammary and lung epithelial cells. The down-regulation of hSRBC expression in cancer cells was associated with hypermethylation of CpG dinucleotides in its promoter region, and 3 (60%) of 5 primary breast tumors and 11 (79%) of 14 primary lung tumors were also found to be hypermethylated. Treatment of breast cancer MCF7 cells with 5'azacytidine and Trichostatin A resulted in expression of hSRBC, confirming DNA methylation as the mode of inactivation. Our results suggest that epigenetic or mutational inactivation of hSRBC may contribute to the pathogenesis of several types of human cancers, marking hSRBC as a candidate tumor suppressor gene.


Asunto(s)
Neoplasias de la Mama/genética , Proteínas Portadoras/genética , Cromosomas Humanos Par 11 , Silenciador del Gen , Péptidos y Proteínas de Señalización Intracelular , Neoplasias Pulmonares/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Neoplasias de la Mama/metabolismo , Proteínas Portadoras/biosíntesis , Pollos , Metilación de ADN , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Genes Supresores de Tumor , Humanos , Neoplasias Pulmonares/metabolismo , Ratones , Datos de Secuencia Molecular , Mutación , Regiones Promotoras Genéticas , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Mapeo de Híbrido por Radiación , Ratas , Homología de Secuencia de Aminoácido
19.
J Mol Biol ; 280(1): 175-82, 1998 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-9653040

RESUMEN

Molten globules are partially structured protein folding intermediates that adopt a native-like overall backbone topology in the absence of extensive detectable tertiary interactions. It is important to determine the extent of specific tertiary structure present in molten globules and to understand the role of specific side-chain packing in stabilizing and specifying molten-globule structure. Previous studies indicate that a small degree of specific side-chain packing stabilizes the structures of the cytochrome c, apomyoglobin, and staphylococcal nuclease molten globules. Here we investigate the extent of specific side-chain packing in the molten globule of alpha-lactalbumin (alpha-LA), a highly fluctuating, non-cooperatively formed molten globule. By analyzing a set of point mutations in the helical domain of alpha-LA, we have identified a stabilizing hydrophobic core. Moreover, this core corresponds to a previously identified structural subdomain and likely contains some native-like packing interactions. Our results suggest that native-like packing of core amino acids helps stabilize molten globules and that some specific interactions can exist in even highly dynamic, fluctuating species.


Asunto(s)
Lactalbúmina/química , Pliegue de Proteína , Estructura Secundaria de Proteína , Lactalbúmina/genética , Modelos Moleculares , Mutagénesis Sitio-Dirigida
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