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1.
Antimicrob Agents Chemother ; : e0026724, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771029

RESUMO

The aim of this study was to analyze the population pharmacokinetics of total and unbound concentrations of prophylactic cefazolin (CFZ) in patients with prostatectomy or nephrectomy. We also aimed to calculate a pharmacodynamics target unbound concentration that exceeded the minimum inhibitory concentration (MIC), to design an effective dosing regimen. Briefly, 614 total concentration and 610 unbound concentration samples from 152 individuals were evaluated, using a nonlinear mixed-effects model. The obtained pharmacodynamics index target value reflected the probability of maintaining CFZ unbound trough concentrations exceeding MIC90, 0.5 mg/L, and MIC50, and 1.0 mg/L, to account for methicillin-susceptible Staphylococcus aureus (MSSA) or Escherichia coli. Population pharmacokinetics were estimated using a two-compartment model with nonlinear protein binding. Unbound systemic clearance (CL) was significantly associated with creatinine clearance, while the maximum protein-binding constant was significantly associated with albumin levels. The probability of achieving an unbound concentration exceeding the MIC50 for E. coli or MIC90 for MSSA in a patient with normal renal function following a 1 g CFZ infusion over 15 min was above 90% at 3 h after the initial dose. Our findings indicated that population pharmacokinetic parameters are useful for determining unbound CFZ pharmacokinetics and evaluating intraoperative CFZ redosing intervals.

2.
Int J Cosmet Sci ; 45(5): 655-671, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37317028

RESUMO

OBJECTIVE: Skin brightness and spot have a significant impact on youthful and beautiful appearance. One important factor influencing skin brightness is the amount of internal reflected light from the skin. Observers recognize the total surface-reflected light and internal reflected light as skin brightness. The more internal reflected light from the skin, the more attractive and brighter the skin appears. This study aims to identify a new natural cosmetic ingredient that increases the skin's internal reflected light, decreases spot and provides a youthful and beautiful skin appearance. METHODS: Lipofuscin in epidermal keratinocytes, the aggregating complex of denatured proteins and peroxidized lipids, is one factor that decreases skin brightness and causes of spot. Aggregates block light transmission, and peroxidized lipids lead to skin yellowness, dullness and age spot. Lipofuscin is known to accumulate intracellularly with ageing. Rapid removal of intracellular denatured proteins prevents lipofuscin formation and accumulation in cells. We focused a proteasome system that efficiently removes intracellular denatured proteins. To identify natural ingredients that increase proteasome activity, we screened 380 extracts derived from natural products. The extract with the desired activity was fractionated and purified to identify active compounds that lead to proteasome activation. Finally, the efficacy of the proteasome-activating extract was evaluated in a human clinical study. RESULTS: We discovered that Juniperus communis fruits (Juniper berry) extract (JBE) increases proteasome activity and suppresses lipofuscin accumulation in human epidermal keratinocytes. We found Anthricin and Yatein, which belong to the lignan family, to be major active compounds responsible for the proteasome-activating effect of JBE. In a human clinical study, an emulsion containing 1% JBE was applied to half of the face twice daily for 4 weeks, resulting in increased internal reflected light, brightness improvement (L-value) and reduction in yellowness (b-value) and spot in the cheek area. CONCLUSION: This is the first report demonstrating that JBE containing Anthricin and Yatein decreases lipofuscin accumulation in human epidermal keratinocytes through proteasome activation, increases brightness and decreases surface spots in human skin. JBE would be an ideal natural cosmetic ingredient for creating a more youthful and beautiful skin appearance with greater brightness and less spot.


OBJECTIF: La luminosité et les taches de peau ont un impact significatif sur la jeunesse et la beauté de l'apparence. L'un des facteurs importants influençant la luminosité de la peau est la quantité de lumière interne réfléchie par la peau. Pour les observateurs, la luminosité de la peau correspond à la somme de la lumière réfléchie par la surface et de la lumière réfléchie par l'intérieur de la peau. Plus la quantité de lumière interne réfléchie par la peau est importante, plus la peau semble attrayante et lumineuse. Cette étude vise à identifier un nouvel ingrédient cosmétique naturel qui augmente la lumière interne réfléchie par la peau, diminue les taches et donne à la peau une apparence jeune et belle. MÉTHODES: La lipofuscine dans les kératinocytes de l'épiderme, le complexe agrégé de protéines dénaturées et de lipides peroxydés, est un facteur qui diminue l'éclat de la peau et qui est à l'origine des taches. Les agrégats bloquent la transmission de la lumière et les lipides peroxydés entraînent une coloration jaune de la peau, un aspect terne et des taches de vieillesse. On sait que la lipofuscine s'accumule au niveau intracellulaire avec le vieillissement. L'élimination rapide des protéines dénaturées intracellulaires empêche la formation et l'accumulation de lipofuscine dans les cellules. Nous avons mis l'accent sur un système de protéasome qui élimine efficacement les protéines dénaturées intracellulaires. Pour identifier les ingrédients naturels qui augmentent l'activité du protéasome, nous avons passé au crible 380 extraits dérivés de produits naturels. L'extrait présentant l'activité souhaitée a été fractionné et purifié afin d'identifier les composés actifs qui conduisent à l'activation du protéasome. Enfin, l'efficacité de l'extrait activant le protéasome a été évaluée dans une étude clinique humaine. RÉSULTATS: Nous avons découvert que l'extrait de Juniperus communis fruits (baie de genièvre) augmente l'activité du protéasome et supprime l'accumulation de lipofuscine dans les kératinocytes épidermiques humains. Nous avons découvert que l'anthricine et la yateine, qui appartiennent à la famille des lignanes, sont les principaux composés actifs responsables de l'effet activateur du protéasome de l'extrait de baies de genévrier. Dans une étude clinique humaine, une émulsion contenant 1 % de JBE a été appliquée sur la moitié du visage deux fois par jour pendant 4 semaines, ce qui a entraîné une augmentation de la lumière interne réfléchie, une amélioration de la luminosité (valeur L) et une réduction de la jaunisse (valeur b) et des taches dans la zone des joues. CONCLUSION: Il s'agit du premier rapport démontrant que l'EBJ contenant de l'anthricine et de la yateine diminue l'accumulation de lipofuscine dans les kératinocytes épidermiques humains par l'activation du protéasome, augmente la luminosité et diminue les taches superficielles de la peau humaine. Le JBE serait un ingrédient cosmétique naturel idéal pour créer une peau plus jeune et plus belle, plus lumineuse et moins tachetée.


Assuntos
Juniperus , Complexo de Endopeptidases do Proteassoma , Humanos , Lipofuscina/metabolismo , Juniperus/metabolismo , Frutas/metabolismo , Queratinócitos/metabolismo , Proteínas
3.
Biopharm Drug Dispos ; 43(3): 108-116, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35508086

RESUMO

Acetaminophen (APAP)-induced liver injury (AILI) is the most common cause of acute liver failure. Although the mechanisms that trigger AILI are well known, it is less understood how to halt AILI progression and facilitate liver recovery. Therefore, it is necessary to understand the pathophysiology of APAP hepatotoxicity in patients and to examine predictive/preventive markers. In a clinical study, we had a case in which aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels increased in a patient with a low ratio of APAP glucuronide concentration (AP-G)/APAP plasma concentration. Then a reverse translational study was conducted for clarifying this clinical question. The relationship between plasma AP-G/APAP concentration ratio and the levels of AST and ALT was examined by in vivo and in vitro experiments. In in vivo experiments, 10-week-old rats showed lower UGT activity, lower AP-G/APAP concentration ratios, and higher AST and ALT levels than 5-week-old rats. This suggests an inverse correlation between the AP-G/APAP concentration ratio and the AST, ALT levels in APAP-treated rats. Furthermore, as a result of the in vitro experiment, it was confirmed that the cell viability decreased when the AP-G/APAP concentration ratio in the culture medium decreased. Since the decrease in the plasma AP-G/APAP concentration ratio appears earlier than the increase of AST and ALT levels, the ratio might be a presymptomatic marker of AILI. When APAP is used for a long time, it is recommended to perform therapeutic drug monitoring of the AP-G/APAP concentration ratio, which is a predictive/preventive marker of AILI.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Doença Hepática Induzida por Substâncias e Drogas , Acetaminofen/efeitos adversos , Acetaminofen/análogos & derivados , Acetaminofen/farmacocinética , Acetaminofen/toxicidade , Alanina Transaminase , Animais , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Humanos , Fígado , Ratos
4.
Int J Cosmet Sci ; 44(2): 154-165, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35133683

RESUMO

OBJECTIVE: Hair loss and greying affect men and women of all ages, often causing psychosocial difficulties. Dickkopf-1 (DKK1), a major hair loss factor secreted from dermal papilla (DP) cells in response to the secretion of dihydrotestosterone (DHT), has been reported to induce and accelerate androgenetic alopecia (AGA). In addition, DKK1 acts as a potent suppressor of melanogenesis and is closely related to hair colour. R-spondin 1 (RSPO1) is a secretory agonist of Wnt signalling known to antagonize the effects of DKK1, including DKK1-mediated hair follicle suppression. In this study, we investigated the effect of watercress extract (WCE) on the secretion of RSPO1 and DKK1 from DP cells as well as its anti-hair loss effect in human hair follicles and patients. METHODS: The in vitro secretion of RSPO1 and DKK1 was measured by ELISA. Human hair follicles were collected from the scalp of a female donor and used for ex vivo organ culture to investigate the effects of WCE on human hair loss. Finally, a 6-month human clinical trial was conducted to examine the effect of WCE-containing lotion on hair growth in a male panel. RESULTS: WCE significantly upregulated RSPO1 secretion and suppressed DKK1 secretion in a dose-dependent manner, even in the presence of DHT. WCE-treated hair follicles elongated 1.6-fold compared with the control, and the level of RSPO1 production in DP as well as RSPO1 bound to the outer root sheath (ORS) increased. In the clinical trial, the hair lotion containing 2% WCE increased hair thickness and density to improve against hair loss symptoms. CONCLUSION: WCE exhibited a strong anti-androgenic effect through its ability to suppress DKK1 secretion and antagonize DKK1 via RSPO1. These findings highlighted the potential use of WCE for the treatment of hair loss.


OBJECTIF: La perte de cheveux et le grisonnement touchent des hommes et des femmes de tous âges, ce qui entraîne souvent des difficultés psychosociales. Selon des rapports, Dickkopf-1 (DKK1), un facteur de perte de cheveux majeur sécrété par les cellules de la papille dermique (PD) en réponse à la sécrétion de dihydrotestostérone (DHT), induit et accélère l'alopécie androgénétique (AAG). En outre, DKK1 agit comme un puissant suppresseur de la mélanogenèse et est étroitement lié à la couleur des cheveux. La protéine R-spondin 1 (RSPO1) est un agoniste sécrétoire de la voie de signalisation Wnt connue pour antagoniser les effets de DKK1, notamment la suppression des follicules pileux médiée par DKK1. Dans cette étude, nous avons étudié l'effet de l'extrait de cresson sur la sécrétion de RSPO1 et de DKK1 à partir des cellules de la PD, ainsi que son effet anti-perte de cheveux sur les follicules pileux humains et chez les patients. MÉTHODES: La sécrétion in vitro de RSPO1 et de DKK1 a été mesurée à l'aide de la méthode ELISA. Des follicules pileux humains ont été prélevés sur le cuir chevelu d'une femme et utilisés pour une culture d'organes ex vivo afin d'étudier les effets de l'extrait de cresson sur la perte de cheveux humains. Enfin, un essai clinique de 6 mois chez l'être humain a été mené pour examiner l'effet d'une lotion contenant de l'extrait de cresson sur la croissance des cheveux au sein d'un panel d'hommes. RÉSULTATS: L'extrait de cresson a significativement régulé à la hausse la sécrétion de RSPO1 et a supprimé la sécrétion de DKK1 de manière dose-dépendante, même en présence de DHT. Les follicules pileux traités avec de l'extrait de cresson ont été multipliés par 1,6 par rapport au groupe témoin, et le niveau de production de RSPO1 dans la PD ainsi que le taux de RSPO1 lié à la gaine externe de la racine ont augmenté. Dans l'essai clinique, la lotion pour cheveux contenant 2 % d'extrait de cresson a augmenté l'épaisseur et la densité des cheveux, améliorant ainsi les symptômes de perte de cheveux. CONCLUSION: La capacité de l'extrait de cresson à supprimer la sécrétion de DKK1 et à antagoniser DKK1 via la protéine RSPO1 lui a conféré un effet anti-androgénique puissant. Ces résultats ont mis en évidence le potentiel de l'extrait de cresson pour le traitement de la perte de cheveux.


Assuntos
Alopecia , Folículo Piloso , Alopecia/tratamento farmacológico , Feminino , Cabelo , Humanos , Masculino , Extratos Vegetais/farmacologia , Couro Cabeludo/metabolismo
5.
PLoS One ; 15(8): e0236321, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32776987

RESUMO

The widely known hue-heat effect, a multisensory phenomenon between vision and thermal sensing, is a hypothesis based on the idea that light and colors affect perceived temperature. However, the application of this effect has not been prevalent in our daily lives. To work towards developing more practical use of the hue-heat effect, we conducted a series of psychophysical experiments to investigate the relationship between perceived temperature and illumination in a well-controlled experimental environment. The results showed that illumination had three types of effects to change our sense of coolness/warmness: creating, eliminating, and exchanging effects. Furthermore, we confirmed the existence of two distinctive time courses for the three effects: creating effect started immediately, but the eliminating effect takes time. These findings provide us with a better understanding of the hue-heat effect and enable us to apply it in everyday life. Paired with the new technologies it can also help with energy conservation.


Assuntos
Percepção de Cores/fisiologia , Iluminação , Sensação Térmica/fisiologia , Feminino , Temperatura Alta , Humanos , Masculino , Estimulação Luminosa/métodos , Psicofísica , Adulto Jovem
6.
Am J Bot ; 105(11): 1813-1823, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30388310

RESUMO

PREMISE OF THE STUDY: Variation in demographic parameters reflects the life-history strategies of plants in response to specific environments. We aimed to investigate the intraspecific variation in life-history traits of a clonal alpine herb, Gentiana nipponica, in various snowmelt conditions. METHODS: Individual ramets within genets accumulate leaves for 7-9 yr without shedding, and die after reproduction. We tested the physiological function of accumulated leaves for reproduction and monitored the ramet demography in early, intermediate, and late snowmelt populations over 3 yr. Then, we simulated ramet dynamics using the demographic parameters. KEY RESULTS: Old leaves had a carbon storage function, and the initiation of reproduction depended on the amount of ramet leaves. Growth and reproductive performance were highest in the population with an intermediate snowmelt period. The early snowmelt population showed short persistence periods due to restricted growth and high mortality of the ramets. The late snowmelt populations showed slow growth, but high survival rate of the ramets, in which the ramet size at reproduction was smallest and fruit formation was often suppressed by the short growing period. CONCLUSIONS: Limiting factors dictating the distribution of G. nipponica differed between the early and late snowmelt habitats. High mortality and restricted growth, because of the harsh environment, determine the distribution limit toward earlier snowmelt locations. By contrast, late snowmelt strongly limited fecundity because of the short period for fruit maturation. The difference in snowmelt time provides a clear gradient of selective forces that may promote local adaptation among neighboring populations.


Assuntos
Gentiana/crescimento & desenvolvimento , Metabolismo dos Carboidratos , Gentiana/metabolismo , Folhas de Planta/metabolismo , Reprodução
7.
Proc Natl Acad Sci U S A ; 108(42): 17314-9, 2011 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-21969538

RESUMO

Staphylococcal γ-hemolysin is a bicomponent pore-forming toxin composed of LukF and Hlg2. These proteins are expressed as water-soluble monomers and then assemble into the oligomeric pore form on the target cell. Here, we report the crystal structure of the octameric pore form of γ-hemolysin at 2.5 Å resolution, which is the first high-resolution structure of a ß-barrel transmembrane protein composed of two proteins reported to date. The octameric assembly consists of four molecules of LukF and Hlg2 located alternately in a circular pattern, which explains the biochemical data accumulated over the past two decades. The structure, in combination with the monomeric forms, demonstrates the elaborate molecular machinery involved in pore formation by two different molecules, in which interprotomer electrostatic interactions using loops connecting ß2 and ß3 (loop A: Asp43-Lys48 of LukF and Lys37-Lys43 of Hlg2) play pivotal roles as the structural determinants for assembly through unwinding of the N-terminal ß-strands (amino-latch) of the adjacent protomer, releasing the transmembrane stem domain folded into a ß-sheet in the monomer (prestem), and interaction with the adjacent protomer.


Assuntos
Proteínas de Bactérias/química , Toxinas Bacterianas/química , Proteínas Hemolisinas/química , Cristalografia por Raios X , Leucocidinas/química , Modelos Moleculares , Complexos Multiproteicos/química , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Estrutura Quaternária de Proteína , Estrutura Secundária de Proteína , Subunidades Proteicas , Proteínas Recombinantes/química , Staphylococcus aureus/química , Staphylococcus aureus/patogenicidade , Eletricidade Estática
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