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1.
Transfus Apher Sci ; 61(3): 103347, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35034842

RESUMEN

Gestational alloimmune liver disease (GALD) is a materno-fetal alloimmune disorder that targets the fetal liver and often causes neonatal liver failure. GALD most commonly presents as neonatal hemochromatosis (NH), which is a severe neonatal liver injury confirmed by extra-hepatic iron accumulation at various sites. With the discovery of the alloimmune mechanism of GALD, exchange transfusion and intravenous immunoglobulin (IVIG) administration are being used as novel treatments. Here, we present a rare case of an 11-day-old female infant who presented with marked hyperbilirubinemia. Laboratory findings showed significantly elevated direct and indirect bilirubin, high ferritin and alpha fetoprotein levels, high transferrin saturation, and severe coagulopathy. Abdominal magnetic resonance imaging revealed markedly reduced T2 signal intensity in the liver and pancreas compared to the spleen, suggesting iron deposition. The infant was diagnosed with NH and successfully treated with exchange transfusion and four doses of IVIG.


Asunto(s)
Enfermedades Fetales , Hemocromatosis , Hepatopatías , Femenino , Hemocromatosis/diagnóstico , Hemocromatosis/tratamiento farmacológico , Humanos , Inmunoglobulinas Intravenosas/uso terapéutico , Lactante , Recién Nacido , Hierro/uso terapéutico
2.
Int J Mol Sci ; 22(10)2021 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-34066270

RESUMEN

With the rapid growth of the wireless communication industry, humans are extensively exposed to electromagnetic fields (EMF) comprised of radiofrequency (RF). The skin is considered the primary target of EMFs given its outermost location. Recent evidence suggests that extremely low frequency (ELF)-EMF can improve the efficacy of DNA repair in human cell-lines. However, the effects of EMF-RF on DNA damage remain unknown. Here, we investigated the impact of EMF-long term evolution (LTE, 1.762 GHz, 8 W/kg) irradiation on DNA double-strand break (DSB) using the murine melanoma cell line B16 and the human keratinocyte cell line HaCaT. EMF-LTE exposure alone did not affect cell viability or induce apoptosis or necrosis. In addition, DNA DSB damage, as determined by the neutral comet assay, was not induced by EMF-LTE irradiation. Of note, EMF-LTE exposure can attenuate the DNA DSB damage induced by physical and chemical DNA damaging agents (such as ionizing radiation (IR, 10 Gy) in HaCaT and B16 cells and bleomycin (BLM, 3 µM) in HaCaT cells and a human melanoma cell line MNT-1), suggesting that EMF-LTE promotes the repair of DNA DSB damage. The protective effect of EMF-LTE against DNA damage was further confirmed by attenuation of the DNA damage marker γ-H2AX after exposure to EMF-LTE in HaCaT and B16 cells. Most importantly, irradiation of EMF-LTE (1.76 GHz, 6 W/kg, 8 h/day) on mice in vivo for 4 weeks reduced the γ-H2AX level in the skin tissue, further supporting the protective effects of EMF-LTE against DNA DSB damage. Furthermore, p53, the master tumor-suppressor gene, was commonly upregulated by EMF-LTE irradiation in B16 and HaCaT cells. This finding suggests that p53 plays a role in the protective effect of EMF-LTE against DNA DSBs. Collectively, these results demonstrated that EMF-LTE might have a protective effect against DNA DSB damage in the skin, although further studies are necessary to understand its impact on human health.


Asunto(s)
Roturas del ADN de Doble Cadena , Campos Electromagnéticos , Queratinocitos/efectos de la radiación , Melanoma/prevención & control , Sustancias Protectoras , Radiación Ionizante , Ondas de Radio , Animales , Apoptosis , Supervivencia Celular , Reparación del ADN , Humanos , Técnicas In Vitro , Queratinocitos/metabolismo , Queratinocitos/patología , Masculino , Melanoma/etiología , Melanoma/patología , Ratones , Ratones Endogámicos C57BL
3.
Sensors (Basel) ; 20(5)2020 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-32121456

RESUMEN

Inertial measurement unit systems are wearable sensors that can measure the movement of a human in real-time with relatively little space and high portability. The purpose of this study was to investigate the accuracy of the inertial measurement unit (IMU) system for gait analysis by comparing it with measurements obtained using an optical motion capture (OMC) system. To compare the accuracies of these two different motion capture systems, the Spatio-temporal and kinematic parameters were measured in young adults during normal walking. Thirty healthy participants participated in the study. Data were collected while walking 5 strides on a 7 m walkway at a self-selected speed. Results of gait analysis showed that the Spatio-temporal (stride time, stride length, cadence, step length) and kinematic (knee joint peak to peak of movement) parameters were not significantly different in the participant. Spatio-temporal and kinematic parameters of the two systems were compared using the Bland-Altman method. The results obtained showed that the measurements of Spatio-temporal and kinematic parameters of gait by the two systems were similar, which suggested that IMU and OMC systems could be used interchangeably for gait measurements. Therefore, gait analysis performed using the wearable IMU system might efficiently provide gait measurements and enable accurate analysis.


Asunto(s)
Marcha/fisiología , Articulación de la Rodilla/fisiología , Adulto , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Análisis Espacio-Temporal , Adulto Joven
4.
J Stroke Cerebrovasc Dis ; 29(7): 104857, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32409256

RESUMEN

BACKGROUND AND PURPOSE: Gait disturbance due to injuries of the descending motor pathway, including corticospinal tract (CST), corticoreticular pathway (CRP), and medial and lateral vestibulospinal tracts (VSTs), are commonly encountered disabling sequelae of pontine hemorrhage. We investigated relations between changes in the CST, CRP, and medial and lateral VST and corresponding changes in gait function in patients with pontine hemorrhage. METHOD: Nine consecutive stroke patients with pontine hemorrhage, and 6 age-matched normal subjects were recruited. Four patients were allocated to group A (can't walk independently) and 5 to group B (can walk independently). Diffusion tensor imaging (DTI) data were acquired twice at acute to subacute stage and chronic stage after stroke onset. Diffusion tensor tractography (DTT) was used to reconstruct CST, CRP, medial and lateral VST. RESULT: The CRP shows a significantly different between groups A and B in both initial and follow up DTT (p > 0.05). In contrast, CST, medial VST and lateral VST did not show a significant difference (p > 0.05). Regarding DTI parameters of CRPs in group A, percentages of patients with fractional anisotropy (FA) and mean diffusivity (MD) values more than two standard deviation from normal were higher by follow up DTI than by initial DTI, however, the CRPs in group B only showed increased abnormal range of MD. CONCLUSIONS: The CST does not play an essential role in recovery of independent walking and vestibulospinal tracts may not crucially affect recovery of independent walking in patients with pontine hemorrhage. In contrast, and intact CRP or changes of the CRP integrity appear to be related to the recovery of gait function.


Asunto(s)
Deambulación Dependiente , Vías Eferentes/fisiopatología , Marcha , Hemorragias Intracraneales/fisiopatología , Limitación de la Movilidad , Puente/irrigación sanguínea , Adulto , Anciano , Estudios de Casos y Controles , Imagen de Difusión Tensora , Vías Eferentes/diagnóstico por imagen , Femenino , Humanos , Hemorragias Intracraneales/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Tractos Piramidales/diagnóstico por imagen , Tractos Piramidales/fisiopatología , Recuperación de la Función , Formación Reticular/diagnóstico por imagen , Formación Reticular/fisiopatología , Núcleo Vestibular Lateral/diagnóstico por imagen , Núcleo Vestibular Lateral/fisiopatología
5.
Am J Physiol Lung Cell Mol Physiol ; 316(5): L872-L885, 2019 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-30675802

RESUMEN

Transcription factor 21 (Tcf21) is a basic helix-loop-helix transcription factor required for mesenchymal development in several organs. Others have demonstrated that Tcf21 is expressed in embryonic lung mesenchyme and that loss of Tcf21 results in a pulmonary hypoplasia phenotype. Although recent single-cell transcriptome analysis has described multiple mesenchymal cell types in the lung, few have characterized the Tcf21 expressing population. To explore the Tcf21 mesenchymal lineage, we traced Tcf21-expressing cells during embryogenesis and in the adult. Our results showed that Tcf21 progenitor cells at embryonic day (E)11.5 generated a subpopulation of fibroblasts and lipofibroblasts and a limited number of smooth muscle cells. After E15.5, Tcf21 progenitor cells exclusively become lipofibroblasts and interstitial fibroblasts. Lipid metabolism genes were highly expressed in perinatal and adult Tcf21 lineage cells. Overexpression of Tcf21 in primary neonatal lung fibroblasts led to increases in intracellular neutral lipids, suggesting a regulatory role for Tcf21 in lipofibroblast function. Collectively, our results reveal that Tcf21 expression after E15.5 delineates the lipofibroblast and a population of interstitial fibroblasts. The Tcf21 inducible Cre mouse line provides a novel method for identifying and manipulating the lipofibroblast.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Pulmón/citología , Pulmón/metabolismo , Adipocitos/citología , Adipocitos/metabolismo , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/deficiencia , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Diferenciación Celular , Linaje de la Célula/genética , Células Cultivadas , Femenino , Fibroblastos/citología , Fibroblastos/metabolismo , Regulación del Desarrollo de la Expresión Génica , Edad Gestacional , Metabolismo de los Lípidos/genética , Pulmón/embriología , Masculino , Mesodermo/citología , Mesodermo/embriología , Mesodermo/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Embarazo
6.
Beilstein J Org Chem ; 14: 1028-1033, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29977375

RESUMEN

Hypervalent iodine-mediated olefin functionalization provides a rapid gateway towards accessing both various heterocyclic cores and functional groups. In this regard, we have developed a Ritter-type alkene functionalization utilizing a PhI(OAc)2 ((diacetoxyiodo)benzene, PIDA)/Lewis acid combination in order to access isoxazoline and pyrazoline cores. Based on allyl ketone oximes and allyl ketone tosylhydrazones, we have developed an alkene oxyamidation and amido-amidation protocol en route to accessing both isoxazoline and pyrazoline cores. Additionally, acetonitrile serves as both the solvent and an amine source in the presence of this PIDA/Lewis acid combination. This operationally straightforward and metal-free protocol provides an easy access to isoxazoline and pyrazoline derivatives.

7.
Proc Natl Acad Sci U S A ; 111(25): 9133-8, 2014 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-24927576

RESUMEN

Platinum drugs are a mainstay of anticancer chemotherapy. Nevertheless, tumors often display inherent or acquired resistance to platinum-based treatments, prompting the search for new compounds that do not exhibit cross-resistance with current therapies. Phenanthriplatin, cis-diamminephenanthridinechloroplatinum(II), is a potent monofunctional platinum complex that displays a spectrum of activity distinct from those of the clinically approved platinum drugs. Inhibition of RNA polymerases by phenanthriplatin lesions has been implicated in its mechanism of action. The present study evaluates the ability of phenanthriplatin lesions to inhibit DNA replication, a function disrupted by traditional platinum drugs. Phenanthriplatin lesions effectively inhibit DNA polymerases ν, ζ, and κ and the Klenow fragment. In contrast to results obtained with DNA damaged by cisplatin, all of these polymerases were capable of inserting a base opposite a phenanthriplatin lesion, but only Pol η, an enzyme efficient in translesion synthesis, was able to fully bypass the adduct, albeit with low efficiency. X-ray structural characterization of Pol η complexed with site-specifically platinated DNA at both the insertion and +1 extension steps reveals that phenanthriplatin on DNA interacts with and inhibits Pol η in a manner distinct from that of cisplatin-DNA adducts. Unlike cisplatin and oxaliplatin, the efficacies of which are influenced by Pol η expression, phenanthriplatin is highly toxic to both Pol η+ and Pol η- cells. Given that increased expression of Pol η is a known mechanism by which cells resist cisplatin treatment, phenanthriplatin may be valuable in the treatment of cancers that are, or can easily become, resistant to cisplatin.


Asunto(s)
Antineoplásicos , Daño del ADN , ADN de Neoplasias , ADN Polimerasa Dirigida por ADN , Proteínas de Neoplasias , Neoplasias , Compuestos Organoplatinos , Fenantridinas , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Cristalografía por Rayos X , ADN de Neoplasias/biosíntesis , ADN de Neoplasias/química , ADN Polimerasa Dirigida por ADN/química , ADN Polimerasa Dirigida por ADN/metabolismo , Resistencia a Antineoplásicos/efectos de los fármacos , Humanos , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Neoplasias/tratamiento farmacológico , Neoplasias/enzimología , Compuestos Organoplatinos/química , Compuestos Organoplatinos/farmacología , Fenantridinas/química , Fenantridinas/farmacología , Relación Estructura-Actividad
8.
J Korean Med Sci ; 32(8): 1288-1294, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28665065

RESUMEN

Prophylactic surfactant is known to be effective to reduce chronic lung disease in preterm infants compared with rescue surfactant treatment. In Korea, early prophylactic surfactant therapy was introduced in 2011. However, recently, the increased utilization of antenatal steroids and early stabilization through continuous positive airway pressure (CPAP) in the delivery room may have changed the risks and benefits of prophylactic surfactant therapy of infants at high risk of respiratory distress syndrome (RDS). We compared the effects and safety of prophylactic surfactant therapy (within 30 minutes after birth) and early selective surfactant therapy (within 3 hours after birth) in preterm infants born at < 30 weeks gestation or with birth weight ≤ 1,250 g. The clinical data of 193 infants in period 1 (from 2008 to 2010, early selective surfactant therapy group) were collected retrospectively; those of 191 infants in period 2 (from 2012 to 2014, prophylactic surfactant therapy group) were collected prospectively. Compared to period 1, the rate of intubation and surfactant use were significantly increased in period 2. The use of multiple doses of surfactant in period 2 was significantly increased compared with period 1. Despite more invasive and aggressive management in period 2, there was no difference in the duration of mechanical ventilation, the incidence of bronchopulmonary dysplasia (BPD) or death, and the risk of other adverse neonatal outcomes between the 2 groups. In conclusion, the benefit of prophylactic surfactant therapy in infants treated under current practices is no longer clear compared to early selective surfactant therapy.


Asunto(s)
Surfactantes Pulmonares/administración & dosificación , Síndrome de Dificultad Respiratoria del Recién Nacido/prevención & control , Displasia Broncopulmonar/epidemiología , Edad Gestacional , Humanos , Incidencia , Lactante , Mortalidad Infantil/tendencias , Recién Nacido , Recien Nacido Prematuro , Recién Nacido de muy Bajo Peso , Unidades de Cuidado Intensivo Neonatal , Oportunidad Relativa , República de Corea , Respiración Artificial , Estudios Retrospectivos
9.
Hum Brain Mapp ; 37(8): 3041-54, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27125904

RESUMEN

Few studies have directly compared the neural correlates of spatial attention (i.e., attention to a particular location) and nonspatial attention (i.e., attention to a feature in the visual scene) using well-controlled tasks. Here, we investigated the neural correlates of spatial and nonspatial attention in humans using intracranial electroencephalography. The topography and number of electrodes showing significant event-related desynchronization (ERD) or event-related synchronization (ERS) in different frequency bands were studied in 13 epileptic patients. Performance was not significantly different between the two conditions. In both conditions, ERD in the low-frequency bands and ERS in the high-frequency bands were present bilaterally in the parietal cortex (prominently on the right hemisphere) and frontal regions. In addition to these common changes, spatial attention involved right-lateralized activity that was maximal in the right superior parietal lobule (SPL), whereas nonspatial attention involved wider brain networks including the bilateral parietal, frontal, and temporal regions, but still had maximal activity in the right parietal lobe. Within the parietal lobe, spatial attention involved ERD or ERS in the right SPL, whereas nonspatial attention involved ERD or ERS in the right inferior parietal lobule. These findings reveal that common as well as different brain networks are engaged in spatial and nonspatial attention. Hum Brain Mapp 37:3041-3054, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.


Asunto(s)
Atención/fisiología , Encéfalo/fisiología , Adolescente , Adulto , Mapeo Encefálico , Electrocorticografía , Femenino , Humanos , Masculino , Adulto Joven
10.
Chemistry ; 22(22): 7574-81, 2016 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-27111128

RESUMEN

The monofunctional platinum anticancer agent phenanthriplatin generates covalent adducts with the purine bases guanine and adenine. Preferential nucleotide binding was investigated by using a polymerase stop assay and linear DNA amplification with a 163-base pair DNA double helix. Similarly to cisplatin, phenanthriplatin forms the majority of adducts at guanosine residues, but significant differences in both the number and position of platination sites emerge when comparing results for the two complexes. Notably, the monofunctional complex generates a greater number of polymerase-halting lesions at adenosine residues than does cisplatin. Studies with 9-methyladenine reveal that, under abiological conditions, phenanthriplatin binds to the N(1) or N(7) position of 9-methyladenine in approximately equimolar amounts. By contrast, comparable reactions with 9-methylguanine afforded only the N(7) -bound species. Both of the 9-methyladenine linkage isomers (N(1) and N(7) ) exist as two diastereomeric species, arising from hindered rotation of the aromatic ligands about their respective platinum-nitrogen bonds. Eyring analysis of rate constants extracted from variable-temperature NMR spectroscopic data revealed that the activation energies for ligand rotation in the N(1) -bound platinum complex and the N(7) -linkage isomers are comparable. Finally, a kinetic analysis indicated that phenanthriplatin reacts more rapidly, by a factor of eight, with 9-methylguanine than with 9-methyladenine, suggesting that the distribution of lesions formed on double-stranded DNA is kinetically controlled. In addition, implications for the potent anticancer activity of phenanthriplatin are discussed herein.


Asunto(s)
Antineoplásicos/farmacología , Nucleótidos/metabolismo , Compuestos Organoplatinos/farmacología , Fenantridinas/farmacología , Antineoplásicos/química , Cisplatino/química , Compuestos Organoplatinos/química , Fenantridinas/química
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