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1.
Commun Biol ; 6(1): 610, 2023 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-37280327

RESUMEN

Chronic heavy alcohol use is associated with lethal arrhythmias. Whether common East Asian-specific aldehyde dehydrogenase deficiency (ALDH2*2) contributes to arrhythmogenesis caused by low level alcohol use remains unclear. Here we show 59 habitual alcohol users carrying ALDH2 rs671 have longer QT interval (corrected) and higher ventricular tachyarrhythmia events compared with 137 ALDH2 wild-type (Wt) habitual alcohol users and 57 alcohol non-users. Notably, we observe QT prolongation and a higher risk of premature ventricular contractions among human ALDH2 variants showing habitual light-to-moderate alcohol consumption. We recapitulate a human electrophysiological QT prolongation phenotype using a mouse ALDH2*2 knock-in (KI) model treated with 4% ethanol, which shows markedly reduced total amount of connexin43 albeit increased lateralization accompanied by markedly downregulated sarcolemmal Nav1.5, Kv1.4 and Kv4.2 expressions compared to EtOH-treated Wt mice. Whole-cell patch-clamps reveal a more pronounced action potential prolongation in EtOH-treated ALDH2*2 KI mice. By programmed electrical stimulation, rotors are only provokable in EtOH-treated ALDH2*2 KI mice along with higher number and duration of ventricular arrhythmia episodes. The present research helps formulate safe alcohol drinking guideline for ALDH2 deficient population and develop novel protective agents for these subjects.


Asunto(s)
Aldehído Deshidrogenasa Mitocondrial , Etanol , Síndrome de QT Prolongado , Animales , Humanos , Ratones , Aldehído Deshidrogenasa Mitocondrial/genética , Arritmias Cardíacas/genética , Pueblos del Este de Asia , Etanol/toxicidad , Síndrome de QT Prolongado/inducido químicamente , Ratones Transgénicos
2.
J Synchrotron Radiat ; 28(Pt 4): 1202-1209, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-34212885

RESUMEN

The Taiwan Photon Source (TPS) with high brightness and energy tunability is suitable for applications in spectroscopy. The tender X-ray absorption beamline will be optimized for X-ray absorption spectroscopy measurements using a bending-magnet source in a unique photon energy range (1.7-10 keV) and two crystal pairs [InSb(111) and Si(111)] separated using back-to-back double-crystal monochromators (DCMs). InSb crystals are typically used in the lower photon energy range of 1.7-3.5 keV. However, the poor thermal conductivity of InSb crystals leads to severe deformation. This factor should be considered when the monochromator is installed on a tender X-ray beamline in a storage ring with a high power density. There are many approaches to reducing the thermal load on the first crystal of a DCM. Double-bounce high harmonics rejection mirrors in front of the DCM serve not only to reduce the high-order harmonics but also to absorb considerable quantities of heat. Two coating stripes on the silicon surfaces with a variable incident angle will be key to solving the thermal load on this beamline.

3.
Environ Int ; 126: 717-726, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30878867

RESUMEN

Long term mining activities can cause significant metal pollution in the environment, thereby showing potential risk to the paddy field. Elucidating the interfacial processes of trace metals from contaminated paddy soil to rice within the rhizosphere can provide important information on metal biogeochemistry and food safety. The current study aims to explore the spatial distribution and molecular speciation of Cu from rhizosphere to rice plant in a mining-impacted paddy soil, and reveal the possible uptake mechanisms. X-ray absorption near edge structure (XANES) analysis indicated that Cu was primarily associated with iron oxide and sulfide in soil with a minor proportion of organic complexed species. In the rice samples, Cu showed much higher concentrations in the roots than the shoots, as most Cu was sequestered in the root surface and epidermis (primarily in the form of C/N ligands bound Cu species), rather than root xylem, as identified by micro X-ray fluorescence (µ-XRF) imaging coupling with µ-XANES. By contrast, in the root xylem, thiol-S bound Cu(I) complex was observed, representing the reduced product of Cu(II) by thiol-S ligands in rice root. The absorbed Cu was probably transported from the root to the aerial part as C/N ligand bound Cu complex such as Cu-histidine like species, which was observed in the root xylem. The large retention capacity and reduction of Cu(II) in rice root alleviated Cu toxicity to rice, which was beneficial for food safety (e.g., lower concentration of Cu in rice grains). These findings showed for the first time that the uptake mechanisms by rice from field contaminated sites, which shed light on Cu detoxification process and potential remediation strategies.


Asunto(s)
Cobre/metabolismo , Oryza/metabolismo , Contaminantes del Suelo/metabolismo , Suelo/química , Transporte Biológico , China , Cobre/química , Minería , Contaminantes del Suelo/química
4.
Sci Total Environ ; 651(Pt 1): 192-202, 2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30227289

RESUMEN

The present study aimed to characterize key physico-chemical and mineralogical attributes of magnetite iron (Fe) ore tailings to identify potential constraints limiting in situ soil formation and direct phytostabilization. Tailings of different age, together with undisturbed local native soils, were sampled from a magnetite mine in Western Australia. Tailings were extremely alkaline (pH > 9.0), with a lack of water stable aggregate and organic matter, and contained abundant primary minerals including mica (e.g., biotite), with low specific surface area (N2-BET around 1.2 m2 g-1). These conditions remained relatively unchanged after four years' aging under field conditions. Chemical extraction and spectroscopic analysis [e.g., X-ray diffraction (XRD) and synchrotron-based Fe K edge X-ray absorption fine structure spectroscopy (XAFS) analysis] revealed that the aging process decreased biotite-like minerals, but increased hematite and magnetite in the tailings. However, the aged tailings lacked goethite, a compound abundant in natural soils. Examination using backscattered-scanning electron microscope - energy dispersive X-ray spectrometry (BSE-SEM-EDS) revealed that aged tailings contained discrete sharp edged Fe-bearing minerals that did not physically integrate with other minerals (e.g., Si/Al bearing minerals). In contrast, Fe minerals in native soils appeared randomly distributed and closely amassed with Si/Al rich phyllosilicates, with highly eroded edges. The lack of labile organic matter and the persistence of alkaline-saline conditions may have significantly hindered the bioweathering of Fe-minerals and the biogenic formation of secondary Fe-minerals in tailings. However, there is signature that a native pioneer plant, Maireana brevifolia can facilitate the bioweathering of Fe-bearing minerals in tailings. We propose that eco-engineering inputs like organic carbon accumulation, together with the introduction of functional microbes and pioneer plants, should be adopted to accelerate bioweathering of Fe-bearing minerals as a priority for initiating in situ soil formation in the Fe ore tailings.

5.
Theranostics ; 6(6): 817-27, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27162552

RESUMEN

Minoxidil (Mx) is a conventional drug for treating androgenetic alopecia, preventing hair loss, and promoting hair growth. The solubility of Mx has been improved using chemical enhancement methods to increase its skin permeability over the long term. This study created a new ultrasound (US) contrast agent-albumin-shelled microbubbles (MBs) that absorb chitosan oligosaccharide lactate (COL) and Mx-and combined it with sonication by US energy in the water phase to enhance hair growth while shortening the treatment period. COL and Mx grafted with MBs (mean diameter of 1480 nm) were synthesized into self-assembled complexes of COL-MBs and Mx-COL-MBs that had mean diameters of 4150 and 4500 nm, respectively. The US was applied at 3 W/cm(2) for 1 min, and combined with Mx-COL-MBs containing 0.3% Mx. The diffusion of Mx through the dialysis membrane from Mx-COL-MB during US (US+Mx-COL-MB) was more rapid at pH 4 than at pH 7.4, which is favorable given that the environment of the scalp is mildly acidic (pH=4.5-5.5). In Franz diffusion experiments performed in vitro, the release rates at 18 hours in the US+Mx-COL-MBs and US+MBs+Mx groups resulted in 2.3 and 1.7 times the penetration and deposition, respectively, of Mx relative to the group with Mx alone. During 21 days treatment in animal experiments, the growth rates at days 10 and 14 in the US+Mx-COL-MBs group increased by 22.6% and 64.7%, respectively, and there were clear significant differences (p<0.05) between the US+Mx-COL-MBs group and the other four groups. The use of US+Mx-COL-MB in the water phase can increased the effects of Mx so as to shorten the telogen phase, and also increase both the diameter of keratinized hair shafts and the size of hair follicles without causing skin damage.


Asunto(s)
Alopecia/tratamiento farmacológico , Sistemas de Liberación de Medicamentos , Cabello/efectos de los fármacos , Microburbujas , Minoxidil/administración & dosificación , Sonicación/métodos , Vasodilatadores/administración & dosificación , Albúminas/administración & dosificación , Animales , Quitosano/administración & dosificación , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Minoxidil/farmacocinética , Resultado del Tratamiento , Vasodilatadores/farmacocinética
6.
Mater Sci Eng C Mater Biol Appl ; 61: 591-8, 2016 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-26838887

RESUMEN

Liquid microemulsions appropriate for topical application were obtained by increasing their viscosity through the addition of thickening agents. The present study first assessed the usefulness of ultrasound (US) plus US contrast agent, microbubbles (MBs), in agarose gel for enhancing transdermal drug delivery. The effect of US plus MBs in agarose gel on the penetration of the skin by magnesium ascorbyl phosphate (MAP) was explored both in vitro and in vivo. In the in vitro experiments, the stability of MBs was investigated by examining the penetration of MAP by the model drug, Evans blue, in two media: an agarose phantom and pig skin. The penetration depth in the agarose phantom and pig skin increased by 40% and 195%, respectively, when treated with US plus MBs in 0.1% agarose solution combined with MAP (UMB1), and by 48% and 206%, respectively, when treated with US plus MBs in 0.15% agarose solution and MAP (UMB2). The skin-whitening effects in C57BL/6J mice in the UMB1 and UMB2 groups over a 4-week experimental period were significantly increased by 63% and 70%, respectively, in the fourth week. The findings of this study suggest that the survival of MBs with US is affected by the viscosity of the surrounding medium, and that in mice, treatment with US plus MBs in a suitable agarose gel can increase skin permeability and enhance transdermal MAP delivery.


Asunto(s)
Ácido Ascórbico , Sistemas de Liberación de Medicamentos/métodos , Microburbujas , Absorción Cutánea , Ondas Ultrasónicas , Administración Cutánea , Animales , Ácido Ascórbico/análogos & derivados , Ácido Ascórbico/farmacocinética , Ácido Ascórbico/farmacología , Ratones , Porcinos
7.
Cell Transplant ; 24(8): 1555-70, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25198179

RESUMEN

Type 1 diabetes mellitus is caused by T-cell-mediated autoimmune destruction of pancreatic ß-cells. Systemic administration of mesenchymal stem cells (MSCs) brings about their incorporation into a variety of tissues with immunosuppressive effects, resulting in regeneration of pancreatic islets. We previously showed that human MSCs isolated from Wharton's jelly (WJ-MSCs) represent a potential cell source to treat diabetes. However, the underlying mechanisms are unclear. The purpose of this study was to discern whether undifferentiated WJ-MSCs can differentiate into pancreatic insulin-producing cells (IPCs) and modify immunological responses in nonobese diabetic (NOD) mice. Undifferentiated WJ-MSCs underwent lentiviral transduction to express green fluorescent protein (GFP) and then were injected into the retro-orbital venous sinus of NOD mice. Seven days after transplantation, fluorescent islet-like cell clusters in the pancreas were apparent. WJ-MSC-GFP-treated NOD mice had significantly lower blood glucose and higher survival rates than saline-treated mice. Systemic and local levels of autoaggressive T-cells, including T helper 1 cells and IL-17-producing T-cells, were reduced, and regulatory T-cell levels were increased. Furthermore, anti-inflammatory cytokine levels were increased, and dendritic cells were decreased. At 23 days, higher human C-peptide and serum insulin levels and improved glucose tolerance were found. Additionally, WJ-MSCs-GFP differentiated into IPCs as shown by colocalization of human C-peptide and GFP in the pancreas. Significantly more intact islets and less severe insulitis were observed. In conclusion, undifferentiated WJ-MSCs can differentiate into IPCs in vivo with immunomodulatory effects and repair the destroyed islets in NOD mice.


Asunto(s)
Diabetes Mellitus Experimental/terapia , Células Secretoras de Insulina/citología , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Linfocitos T/inmunología , Gelatina de Wharton/citología , Animales , Autoinmunidad , Glucemia/análisis , Péptido C/sangre , Diferenciación Celular , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Diabetes Mellitus Experimental/mortalidad , Diabetes Mellitus Experimental/patología , Femenino , Humanos , Insulina/sangre , Células Secretoras de Insulina/metabolismo , Masculino , Ratones , Ratones Endogámicos NOD , Tasa de Supervivencia , Linfocitos T/citología , Linfocitos T/metabolismo
8.
Biomed Res Int ; 2014: 840852, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25254216

RESUMEN

Gene therapy for sensorineural hearing loss has recently been used to insert genes encoding functional proteins to preserve, protect, or even regenerate hair cells in the inner ear. Our previous study demonstrated a microbubble- (MB-)facilitated ultrasound (US) technique for delivering therapeutic medication to the inner ear. The present study investigated whether MB-US techniques help to enhance the efficiency of gene transfection by means of cationic liposomes on HEI-OC1 auditory cells and whether MBs of different sizes affect such efficiency. Our results demonstrated that the size of MBs was proportional to the concentration of albumin or dextrose. At a constant US power density, using 0.66, 1.32, and 2.83 µm albumin-shelled MBs increased the transfection rate as compared to the control by 30.6%, 54.1%, and 84.7%, respectively; likewise, using 1.39, 2.12, and 3.47 µm albumin-dextrose-shelled MBs increased the transfection rates by 15.9%, 34.3%, and 82.7%, respectively. The results indicate that MB-US is an effective technique to facilitate gene transfer on auditory cells in vitro. Such size-dependent MB oscillation behavior in the presence of US plays a role in enhancing gene transfer, and by manipulating the concentration of albumin or dextrose, MBs of different sizes can be produced.


Asunto(s)
Técnicas de Transferencia de Gen , Terapia Genética , Pérdida Auditiva Sensorineural/genética , Albúminas/administración & dosificación , Albúminas/química , Línea Celular , Glucosa/química , Células Ciliadas Auditivas Internas/patología , Células Ciliadas Auditivas Internas/efectos de la radiación , Pérdida Auditiva Sensorineural/terapia , Humanos , Liposomas/administración & dosificación , Liposomas/química , Microburbujas , Sonido
9.
Chin J Physiol ; 53(2): 105-11, 2010 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-21793317

RESUMEN

The aim of this study was to examine the effects of Eleutherococcus senticosus (ES) supplementation on endurance capacity, cardiovascular functions and metabolism of recreationally trained males for 8 weeks. Nine recreationally trained males in college consumed 800 mg/d of ES or starch placebo (P) for 8 weeks according to a double-blind, randomized, placebo controlled and crossover design with a washout period of 4 weeks between the cycling trials. Subjects cycled at 75% VO2 peak until exhaustion. The examined physiological variables included endurance time, maximal heart rate during exhaustion exercise, VO2, rating of perceived exertion and respiratory exchange ratio. The biochemical variables including the plasma free fatty acid (FFA) and glucose were measured at rest, 15 min, 30 min and exhaustion. The major finding of this study was the VO2 peak of the subjects elevated 12% (P < 0.05), endurance time improved 23% (P < 0.05) and the highest heart rate increased 4% (P < 0.05) significantly. The second finding was at 30 min of 75% VO2 peak cycling, the production of plasma FFA was increased and the glucose level was decreased both significantly (P < 0.05) over 8-week ES supplementation. This is the first well-conducted study that shows that 8-week ES supplementation enhances endurance capacity, elevates cardiovascular functions and alters the metabolism for sparing glycogen in recreationally trained males.


Asunto(s)
Suplementos Dietéticos , Medicamentos Herbarios Chinos/farmacología , Eleutherococcus , Metabolismo/efectos de los fármacos , Resistencia Física/efectos de los fármacos , Adolescente , Glucemia/metabolismo , Estudios Cruzados , Método Doble Ciego , Medicamentos Herbarios Chinos/administración & dosificación , Ácidos Grasos no Esterificados/sangre , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Metabolismo/fisiología , Consumo de Oxígeno/efectos de los fármacos , Consumo de Oxígeno/fisiología , Resistencia Física/fisiología , Factores de Tiempo , Adulto Joven
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