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1.
Skin Res Technol ; 28(3): 455-464, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35261091

RESUMEN

OBJECTIVE: To determine the aesthetical accordance between a given skin tone and the 11 possible colours of head hairs, covered by a marketed hair colouration product. MATERIAL AND METHODS: The photographs of professional top models, representing several ancestries (non-Hispanic European and Euro-American, East Asian, Hispanic Euro-American, and African-American ancestries), were used to virtually modify skin tones (from light, medium to dark) and hair colour by an artificial intelligence (AI)-based algorithm. Hence, 117 modified photographs were then assessed by five local panels of about 60 women each (one in China, one in France and three in US). The same questionnaire was given to the panels, written in their own language, asking which and how both skin tones and hair colours fit preferentially (or not appreciated), asking in addition the reasons of their choices, using fixed wordings. RESULTS: Answers from the five panels differed according to origin or cultural aspects, although some agreements were found among both non-Hispanic European and Euro-American groups. The Hispanic American panel in US globally much appreciated darker hair tones (HTs). Two panels (East Asian in China and African American in US) and part of non-Hispanic European panel in France declared appreciating all HTs, almost irrespective with the skin tone (light, medium and dark). This surprising result is very likely caused by gradings (in %) that differ by too low values, making the establishment of a decisive or significant assessment. By nature highly subjective (culturally and/or fashion driven), the assessments should be more viewed as trends, an unavoidable limit of the present virtual approach. The latter offers nevertheless a full respect of ethical rules as such objective could hardly be conducted in vivo: applying 10 or 11 hair colourations on the same individual is an unthinkable option. CONCLUSION: The virtual approach developed in the present study that mixes two major facial coloured phenotypes seems at the crossroad of both genetic backgrounds and the secular desire of a modified appearance. Nonetheless, this methodology could afford, at the individual level in total confidentiality, a great help to subjects exposed to some facial skin disorders or afflictions.


Asunto(s)
Color del Cabello , Pigmentación de la Piel , Inteligencia Artificial , Pueblo Asiatico , Femenino , Antecedentes Genéticos , Humanos
2.
Brain Res ; 1663: 184-193, 2017 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-28322751

RESUMEN

Neurons depend on mitochondria for homeostasis and survival, and thus, mitochondrial dysfunction has been implicated in neurodegenerative diseases, including Parkinson's disease (PD). Increasing evidence indicates the mitochondrial uncoupler, 2,4-dinitrophenol (DNP), protects neurons against neurodegeneration and enhances neural plasticity. Here, the authors evaluated the protective effects of intraperitoneally (i.p.) administered low dose DNP in an acute mouse model of PD. Mice were administered DNP (1 or 5mg/kg) for 12 consecutive days, and then on day 13, MPTP (20mg/kg, i.p.) was administered four times (with 2h intervals between injections) to induce PD. It was found that MPTP-induced motor dysfunction was ameliorated in the DNP-treated mice versus vehicle-treated controls. Additionally, DNP effectively attenuated dopaminergic neuronal loss observed in MPTP treated mice. Moreover, in primary cultured neurons, DNP at 10µM, but not at 100µM, prevented MPP+-induced cell death and mitochondrial membrane potential (MMP) reduction. In addition, DNP was observed to cause the nuclear translocation of Nrf2 in primary neurons. Taken together, these findings of the present study suggest that DNP protects dopaminergic neurons against neurodegeneration and maintains MMP integrity in PD by activating adaptive stress responses.


Asunto(s)
2,4-Dinitrofenol/uso terapéutico , Enfermedad de Parkinson/metabolismo , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/farmacología , 2,4-Dinitrofenol/metabolismo , 2,4-Dinitrofenol/farmacocinética , Animales , Muerte Celular/efectos de los fármacos , Dinitrofenoles/metabolismo , Modelos Animales de Enfermedad , Dopamina/metabolismo , Neuronas Dopaminérgicas/efectos de los fármacos , Intoxicación por MPTP/fisiopatología , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Mitocondrias/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Sustancia Negra/efectos de los fármacos
3.
Arch Pharm Res ; 39(8): 1160-70, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27469335

RESUMEN

Bee venom (BV), also known as apitoxin, is widely used in traditional oriental medicine to treat immune-related diseases. Recent studies suggest that BV could be beneficial for the treatment of neurodegenerative diseases. Parkinson's disease (PD) is the second most common neurodegenerative disease next to Alzheimer's disease, and PD pathologies are closely associated with neuroinflammation. Previous studies have suggested the neuroprotective effects of BV in animal models of PD are due to the modulation of inflammation. However, the molecular mechanisms responsible for the anti-neuroinflammatory effect of BV have not been elucidated in astrocytes. Here, the authors investigated the neuroprotective effects of BV and pramipexole (PPX; a positive control) in a subchronic MPTP-induced murine PD model. Both BV and PPX prevented MPTP-induced impairments in motor performance and reduced dopaminergic neuron loss, and furthermore, these neuroprotective effects of BV and PPX were found to be associated with reduced astroglial activation in vivo PD model. However, in MPP(+) treated primary cultured astrocytes, BV modulated astrocyte activation, whereas PPX did not, indicating that the neuroprotective effects of PPX were not mediated by neuroinflammation. These findings suggest that BV should be considered a potential therapeutic or preventive agent for PD and other neuroinflammatory associated disorders.


Asunto(s)
Astrocitos/metabolismo , Venenos de Abeja/uso terapéutico , Intoxicación por MPTP/metabolismo , Intoxicación por MPTP/prevención & control , Fármacos Neuroprotectores/uso terapéutico , Animales , Astrocitos/efectos de los fármacos , Astrocitos/patología , Venenos de Abeja/farmacología , Células Cultivadas , Femenino , Intoxicación por MPTP/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Fármacos Neuroprotectores/farmacología , Embarazo , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Resultado del Tratamiento
4.
J Neurosci Res ; 94(10): 865-78, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27265894

RESUMEN

Parkinson's disease (PD) is one of the most common neurodegenerative disorders and is characterized by loss of dopaminergic neurons in the substantia nigra (SN). Although the causes of PD are not understood, evidence suggests that oxidative stress, mitochondrial dysfunction, and inflammation are associated with its pathogenesis. Morin (3,5,7,2',4'-pentahydroxyflavone) is a flavonol found in wine and many herbs and fruits. Previous studies have suggested that morin prevents oxidative damage and inflammation and ameliorates mitochondrial dysfunction. The present study describes the neuroprotective effects of morin in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model of PD, and we report the results of our investigation into its neuroprotective mechanism in primary neurons and astrocytes. In the mouse model, morin pretreatment ameliorated motor dysfunction, protected against dopaminergic neuronal losses in SN and striatum, and alleviated MPTP-induced astrocyte activation. In vitro studies revealed that morin protected primary cultured neurons against 1-methyl-4-phenylpyridine (MPP(+) )-mediated reactive oxygen species production and mitochondrial membrane potential (MMP) disruption. In addition, morin effectively reduced MPP(+) -induced astroglial activation and nuclear translocation of nuclear factor-κB in primary cultured astrocytes. These results indicate that morin acts via multiple neuroprotective mechanisms in our mouse model and suggest that morin be viewed as a potential treatment and preventative for PD. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Flavonoides/uso terapéutico , Intoxicación por MPTP/inducido químicamente , Intoxicación por MPTP/tratamiento farmacológico , Neuroprostanos/uso terapéutico , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/farmacología , Animales , Animales Recién Nacidos , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Células Cultivadas , Corteza Cerebral/citología , Modelos Animales de Enfermedad , Embrión de Mamíferos , Flavonoides/química , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Actividad Motora/efectos de los fármacos , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuroprostanos/farmacología , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo
5.
Brain Res ; 1627: 233-42, 2015 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-26434409

RESUMEN

Parkinson's disease (PD) is the second-most common neurodegenerative disease after Alzheimer's disease, and is characterized by dopaminergic neuronal loss in midbrain. The MPTP-induced PD model has been well characterized by motor deficits and selective dopaminergic neuronal death accompanied by glial activation. Silibinin is a constituent of silymarin, an extract of milk thistle seeds, and has been proposed to have hepatoprotective, anti-cancer, anti-oxidative, and neuroprotective effects. In the present study, the authors studied the neuroprotective effects of silibinin in an acute MPTP model of PD. Silibinin was administered for 2 weeks, and then MPTP was administered to mice over 1 day (acute MPTP induced PD). Silibinin pretreatment effectively ameliorated motor dysfunction, dopaminergic neuronal loss, and glial activations caused by MPTP. In addition, an in vitro study demonstrated that silibinin suppressed astroglial activation and ERK and JNK phosphorylation in primary astrocytes in response to MPP(+) treatment. These findings show silibinin protected dopaminergic neurons in an acute MPTP-induced mouse model of PD, and suggest its neuroprotective effects might be mediated by the suppression of astrocyte activation via the inhibition of ERK and JNK phosphorylation. In conclusion, the study indicates silibinin should be viewed as a potential treatment for PD and other neurodegenerative diseases associated with neuroinflammation.


Asunto(s)
Antioxidantes/uso terapéutico , Astrocitos/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Intoxicación por MPTP/complicaciones , Intoxicación por MPTP/tratamiento farmacológico , Silimarina/uso terapéutico , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/farmacología , Animales , Animales Recién Nacidos , Antioxidantes/química , Células Cultivadas , Corteza Cerebral/citología , Modelos Animales de Enfermedad , Inhibidores Enzimáticos/farmacología , Proteína Ácida Fibrilar de la Glía/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Actividad Motora/efectos de los fármacos , Ratas Sprague-Dawley , Silibina , Silimarina/química , Factores de Tiempo , Tirosina 3-Monooxigenasa/metabolismo
6.
J Phys Chem Lett ; 6(13): 2629-35, 2015 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-26266745

RESUMEN

We used electrostatic force microscopy (EFM) to investigate local conducting states of atomically thin individual graphene oxide (GO) sheets and monitor the spatial evolution of their conducting properties during the reduction process. Because of the thinness of the GO sheets and finite carrier density, the electric field is partially screened in the reduced GO, which is manifested in the EFM phase signals. We found inhomogeneous oxidation states in as-prepared GO sheets and followed the evolution of reduction process in the individual GO sheets during both thermal and chemical reduction. We also compared the EFM measurement results with simultaneous IV characteristics to assess correlations between two measurements.

7.
ACS Appl Mater Interfaces ; 6(16): 13430-7, 2014 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-25122074

RESUMEN

We report fully solution-processed fabrication of transparent conducting oxide-free counter electrodes (CEs) for dye-sensitized solar cells (DSSCs) by combining spray-coating of single-wall carbon nanotubes (SWCNTs) and chemical reduction of chloroplatinic acid precursor to platinum nanoparticles (Pt NPs) with formic acid. The power conversion efficiency of a semitransparent DSSC with such SWCNT-based CE loaded with Pt NPs is comparable to that of a control device with a conventional CE. Quantification of Pt loading shows that network morphology of entangled SWCNTs is efficient in forming and retaining chemically reduced Pt NPs. Moreover, electron microscopy and electrochemical impedance spectroscopy results show that mainly Pt NPs, which are tens of nanometers in diameter and reside at the surface of SWCNT CEs, contribute to electrocatalytic activity for triiodide reduction, to which we attribute strong correlation between power conversion efficiency of DSSCs and time constant deduced from equivalent-circuit analysis of impedance spectra.

8.
ACS Nano ; 8(3): 2857-63, 2014 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-24533638

RESUMEN

We report the fabrication of efficient indium-tin-oxide-free organic solar cells based on poly(3-hexylthiophene-2,5-diyl):[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PCBM). All layers of the devices from the lowermost silver nanowire cathode to the uppermost conducting polymer anode are deposited from solution and processed at plastic-compatible temperatures<200 °C. Owing to the absence of an opaque metal electrode, the devices are semitransparent with potential applications in power-generating windows and tandem-cells. The measured power conversion efficiencies (PCEs) of 2.3 and 2.0% under cathode- and anode-side illumination, respectively, match previously reported PCE values for equivalent semitransparent organic solar cells using indium tin oxide.

9.
Nanotechnology ; 18(3): 035606, 2007 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-19636129

RESUMEN

The growth of ZnO nanorods on Au-coated ITO substrates using a low temperature wet chemical process is presented. Electron microscopy and x-ray diffraction observations reveal that the crystalline ZnO nanorods are preferentially oriented along the c axis. Room temperature photoluminescence (PL) measurements reveal a strong band edge emission at 382 nm, a signature of good crystallinity, with a weak and broad orange-red emission, which is typically attributed to the oxygen interstitials, in the range between 520 and 720 nm. Other than the second order feature of the band edge emission at 760 nm, no red or near-infrared bands are observed. The effect of precursor concentration on the morphological, structural and PL properties are studied, and the results are discussed.

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