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1.
Exp Neurobiol ; 32(6): 395-409, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38196135

RESUMO

The µ-opioid receptor (MOR) is a class of opioid receptors characterized by a high affinity for ß-endorphin and morphine. MOR is a G protein-coupled receptor (GPCR) that plays a role in reward and analgesic effects. While expression of MOR has been well established in neurons and microglia, astrocytic MOR expression has been less clear. Recently, we have reported that MOR is expressed in hippocampal astrocytes, and its activation has a critical role in the establishment of conditioned place preference. Despite this critical role, the expression and function of astrocytic MOR from other brain regions are still unknown. Here, we report that MOR is significantly expressed in astrocytes and GABAergic neurons from various brain regions including the hippocampus, nucleus accumbens, periaqueductal gray, amygdala, and arcuate nucleus. Using the MOR-mCherry reporter mice and Imaris analysis, we demonstrate that astrocytic MOR expression exceeded 60% in all tested regions. Also, we observed similar MOR expression of GABAergic neurons as shown in the previous distribution studies and it is noteworthy that MOR expression is particularly in parvalbumin (PV)-positive neurons. Furthermore, consistent with the normal MOR function observed in the MOR-mCherry mouse, our study also demonstrates intact MOR functionality in astrocytes through iGluSnFr-mediated glutamate imaging. Finally, we show the sex-difference in the expression pattern of MOR in PV-positive neurons, but not in the GABAergic neurons and astrocytes. Taken together, our findings highlight a substantial astrocytic MOR presence across various brain regions.

2.
Front Mol Neurosci ; 15: 947192, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35875661

RESUMO

The incidence of depression among adolescents has been rapidly increasing in recent years. Environmental and genetic factors have been identified as important risk factors for adolescent depression. However, the mechanisms underlying the development of adolescent depression that are triggered by these risk factors are not well understood. Clinical and preclinical studies have focused more on adult depression, and differences in depressive symptoms between adolescents and adults make it difficult to adequately diagnose and treat adolescent depression. Brain-derived neurotrophic factor (BDNF) is known to play a critical role in the pathophysiology of many psychiatric disorders, including depression. However, there are still few studies on adolescent depression. Therefore, in this review paper, the causes and treatment of adolescent depression and the function of BDNF are investigated.

3.
Nature ; 605(7910): 427-428, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35585335
4.
Sci Rep ; 10(1): 16937, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33037237

RESUMO

We propose a monolithic focus-tunable lens structure based on the dielectric-elastomer actuator (DEA) technology. In our focus-tunable lens, a soft lens and radial in-plane actuator mimicking the ocular focal-tuning mechanism are constructed in a single body of an optimized dielectric-elastomer film. We provide device fabrication methods including elastomer synthesis, structure formation, and packaging process steps. Performance test measurements show 93% focal tunability and 7 ms response time under static and dynamic electrical driving conditions, respectively. These performance characteristics are substantially enhanced from the previous polylithic DEA tunable lens by a factor 1.4 for the focal tunability and a factor 9.4 for the dynamic tuning-speed limit. Therefore, we obtain greatly enhanced focal tuning control in a remarkably simple and compact device structure.

5.
Sci Rep ; 8(1): 16118, 2018 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-30382147

RESUMO

Optical tactile sensors based on a directional coupler have been widely investigated because of their many advantages. However, one important requirement limits their wide application: the refractive index of the upper superstrate must be equal to or larger than that of the optical waveguide core. To overcome this disadvantage, an optical waveguide tactile sensor using graphene is proposed and its operational feasibility was validated experimentally. The pressure-dependent lateral deformation of the low-index prism-like microstructure on an elastomer superstrate has a key role in optically measuring the mechanical pressure. By mechanically varying the lateral deformation area, the waveguide core-graphene-polydimethylsiloxane (PDMS) interface area was adjusted and the amount of light absorption by graphene became tunable, even when the refractive index of the superstrate was lower than that of the waveguide core. The dynamic response of the sensor was accurately matched to the repeated pressing and release time of the pressure, and exhibited a real-time response to multi-stepped mechanical pressing and releasing using a piezoelectric motor. The proposed graphene-based optical tactile sensor is foundational to the use of a wide range of materials for overcoming the shortcoming of a directional coupler-based optical tactile sensor.

6.
Nat Prod Res ; 27(12): 1132-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22840217

RESUMO

Pancreatic lipase digests dietary fats by hydrolysis, which is a key enzyme for lipid absorption. Therefore, reduction of fat absorption by the inhibition of pancreatic lipase is suggested to be a therapeutic strategy for obesity. From the EtOAc-soluble fraction of the stem barks of Fraxinus rhynchophylla (Oleaceae), four secoiridoids such as ligstroside (1), oleuropein (2), 2"-hydroxyoleuropein (3) and hydroxyframoside B (4) were isolated. The inhibitory activity of these compounds on pancreatic lipase was assessed using porcine pancreatic lipase as an in vitro assay system. Compound 4 showed the strongest inhibition on pancreatic lipase, which followed by compounds 1-3. In addition, compound 4 exerted inhibitory effect on pancreatic lipase in a mixed mechanism of competitive and noncompetitive manner. Taken together, F. rhynchophylla and its constituents might be beneficial to obesity.


Assuntos
Inibidores Enzimáticos/farmacologia , Fraxinus/química , Iridoides/farmacologia , Lipase/antagonistas & inibidores , Pâncreas/enzimologia , Animais , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores Enzimáticos/química , Glucosídeos/isolamento & purificação , Glucosídeos/farmacologia , Glucosídeos Iridoides , Iridoides/química , Iridoides/isolamento & purificação , Casca de Planta/química , Piranos/isolamento & purificação , Piranos/farmacologia , Suínos
7.
Nat Prod Commun ; 6(9): 1267-8, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21941895

RESUMO

From the CHCl3-soluble fraction of the fruits of Garcinia mangostana (Clusiaceae), six xanthone derivatives, alpha-mangostin (1), gamma-mangostin (2), gartanin (3), deoxygartanin (4), 1-isomangstanin (5) and garcinone E (6), were isolated. All these compounds significantly inhibited HSC-T6 viability as assessed by employing HSC-T6 hepatic stellate cells as an in vitro assay system. Among them, compounds 1 and 2, the most potent and major constituents of G. mangostana, inhibited HSC-T6 viability in dose- and time-dependent manners. In addition, compounds 1 and 2 significantly reduced collagen content, a pathological characteristic of liver fibrosis. Taken together, G. mangostana and its constituents might be beneficial for the treatment of liver fibrosis.


Assuntos
Garcinia/química , Xantonas/química , Xantonas/farmacologia , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Frutas/química , Células Estreladas do Fígado/efeitos dos fármacos , Estrutura Molecular , Ratos
8.
Bioresour Technol ; 102(19): 9020-5, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21840709

RESUMO

1-Ethyl-3-methylimidazolium acetate ([Emim][CH3COO]) was used for the extraction of lignin from poplar wood (Populus albaglandulosa), which was called to ionic liquid lignin (ILL) and structural features of ILL were compared with the corresponding milled wood lignin (MWL). Yields of ILL and MWL were 5.8±0.3% and 4.4±0.4%, respectively. The maximum decomposition rate (V(M)) and temperature (T(M)) corresponding to V(M) were 0.25%/ °C and 308.2 °C for ILL and 0.30%/ °C and 381.3 °C for MWL. The amounts of functional groups (OMe and phenolic OH) appeared to be similar for both lignins; approximately 15.5% and 6.7% for ILL and 14.4% and 6.3% for MWL. However, the weight average molecular weight (M(w)) of ILL (6347 Da) was determined to be 2/3-fold of that of MWL (10,002 Da) and polydispersity index (PDI: M(w)/M(n)) suggested that the lignin fragments were more uniform in the ILL (PDI 1.62) than in the MWL (PDI 2.64).


Assuntos
Líquidos Iônicos/química , Lignina/química , Populus/química , Cromatografia em Gel , Imidazóis , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termogravimetria
9.
Planta Med ; 77(10): 1020-3, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21294077

RESUMO

Fraxinus rhynchophylla showed significant inhibitory activity on adipocyte differentiation in the 3T3-L1 preadipocyte cell line as assessed by measuring fat accumulation using Oil Red O staining. Further fractionation led to the isolation of two secoiridoids, oleuropein and hydroxyframoside B. Hydroxyframoside B significantly reduced fat accumulation and triglyceride content in differentiated 3T3-L1 cells without affecting cell viability, whereas oleuropein showed little effect. Further studies with interval treatment demonstrated that hydroxyframoside B exerted inhibitory activity on adipocyte differentiation when treated within 2 days (days 0-2) after differentiation induction. In addition, hydroxyframoside B significantly blocked the induction of adipogenic transcription factors such as C/EBP α, C/EBP ß, and PPAR γ. Taken together, these results suggest that hydroxyframoside B inhibited early/middle stage of adipogenic differentiation, in part, via inhibition of C/EBP α, C/EBP ß, and PPAR γ-dependent pathways.


Assuntos
Adipócitos/efeitos dos fármacos , Fármacos Antiobesidade/farmacologia , Diferenciação Celular/efeitos dos fármacos , Fraxinus/química , Iridoides/farmacologia , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/metabolismo , Animais , Proteína alfa Estimuladora de Ligação a CCAAT/antagonistas & inibidores , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/antagonistas & inibidores , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Avaliação Pré-Clínica de Medicamentos , Iridoides/química , Camundongos , PPAR gama/antagonistas & inibidores , PPAR gama/metabolismo , Transdução de Sinais/efeitos dos fármacos , Triglicerídeos/metabolismo
10.
J Nat Med ; 65(2): 370-4, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21082271

RESUMO

The CHCl(3) fraction of Cnidium monnieri fruits significantly inhibited the proliferation of hepatic stellate cells in an in-vitro assay system employing HSC-T6 hepatic stellate cell lines. Activity-guided fractionation of the CHCl(3) fraction of C. monnieri led to the isolation of ten coumarins: osthol (1), meranzin (2), auraptenol (3), meranzin hydrate (4), 7-hydroxy-8-methoxy coumarin (5), imperatorin (6), xanthotoxol (7), xanthotoxin (8), bergapten (9) and isopimpinellin (10). Of these, compounds 1 and 6 significantly inhibited proliferation of HSCs in a time- and concentration-dependent manner. In addition, compounds 1 and 6 significantly reduced collagen content in HSC-T6 cells.


Assuntos
Cnidium/química , Cumarínicos/química , Cumarínicos/farmacologia , Frutas/química , Células Estreladas do Fígado/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Células Estreladas do Fígado/citologia , Estrutura Molecular , Extratos Vegetais/química , Ratos
11.
Biol Pharm Bull ; 33(9): 1610-4, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20823583

RESUMO

In the course of screening anti-adipogenic activity of natural products employing the preadipocyte cell line, 3T3-L1 as an in vitro assay system, the EtOAc fraction of the stem barks of Fraxinus rhynchophylla DENCE (Oleaceae) showed significant inhibitory activity on adipocyte differentiation as assessed by measuring fat accumulation using Oil Red O staining. Activity-guided fractionation led to the isolation of six coumarins such as esculetin (1), scopoletin (2), fraxetin (3), fraxidin (4) esculin (5) and fraxin (6). Among the six coumarins isolated, esculetin (1) showed the most potent inhibitory activity on adipocyte differentiation, followed by fraxetin (3). Further studies with interval treatment demonstrated that esculetin (1) exerted inhibitory activity on adipocyte differentiation when treated within 2 d (days 0-2) after differentiation induction. We further investigated the effect of esculetin (1) on peroxisome proliferator activated receptor gamma (PPARgamma), one of the early adipogenic transcription factors. Esculetin (1) significantly blocked the induction of PPARgamma protein expression and inhibited adipocyte differentiation induced by troglitazone, a PPARgamma agonist. Taken together, these results suggest that esculetin (1), an active compound from F. rhynchophylla, inhibited early stage of adipogenic differentiation, in part, via inhibition of PPARgamma-dependent pathway.


Assuntos
Adipócitos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Cumarínicos/farmacologia , Fraxinus , Inibidores do Crescimento/farmacologia , Casca de Planta , Caules de Planta , Células 3T3-L1 , Adipócitos/citologia , Animais , Diferenciação Celular/fisiologia , Cumarínicos/isolamento & purificação , Inibidores do Crescimento/isolamento & purificação , Camundongos , PPAR gama/antagonistas & inibidores , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Umbeliferonas/isolamento & purificação , Umbeliferonas/farmacologia
12.
Surg Laparosc Endosc Percutan Tech ; 18(6): 611-5, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19098672

RESUMO

Paraduodenal hernia is a congenital internal hernia caused by abnormal retroperitoneal fixation of the intestinal mesentery. The management of paraduodenal hernia consists of reduction of the herniated intestine and repair of the defect. Recently, laparoscopic surgery has been increasingly performed in abdominal procedures. To evaluate the feasibility and efficacy of laparoscopic repair of paraduodenal hernia, we present our experience in 2 cases of laparoscopic repair, compared with 3 other cases treated with conventional open repair; all 5 cases were successfully treated. All patients had symptoms of intestinal obstruction and were diagnosed by preoperative abdominal computed tomography. Two cases were right-sided hernias, and 3 cases were left sided. Among them, 2 patients with left-sided paraduodenal hernia underwent laparoscopic reduction (LR group) of the herniated small bowel, and the other 3 cases underwent open reduction (OR group). In the LR group, the duration of hospital stay, time to first flatus, and time to first intake of a soft diet were shorter than in the OR group. Thus, with an accurate preoperative diagnosis of paraduodenal hernia, laparoscopic surgery may be a feasible and efficient procedure, with good postoperative outcomes.


Assuntos
Duodenopatias/congênito , Duodenopatias/cirurgia , Hérnia/congênito , Herniorrafia , Laparoscopia/métodos , Idoso , Duodenopatias/diagnóstico , Estudos de Viabilidade , Feminino , Hérnia/diagnóstico , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Adulto Jovem
13.
Taehan Kanho Hakhoe Chi ; 37(5): 781-9, 2007 Aug.
Artigo em Coreano | MEDLINE | ID: mdl-17804945

RESUMO

PURPOSE: The study was conducted to investigate the skin hydration level in various body sites and identify the influencing factors in neonates. METHODS: An exploratory comparison study was designed to measure the stratum corneum hydration, using a National DM-R2 on the forehead, abdomen, buttocks, and the back of the hands and feet of 198 neonates including 92 premature infants. RESULTS: The results showed 32.7%-36.5% of stratum corneum hydration for all sites. Premature infants revealed a higher hydration level on the peripheral sites (dorsal hand and feet) than those of the full-term infants, possibly resulting from therapeutic regimens including an incubator or radiant warmer. Infants in an incubator showed a higher hydration level than those in radiant warmers, suggesting more attention to fluid management for infants in the open environment. In addition, all stratum corneum hydration measurements except one, from the forehead, showed a positive correlation with postnatal age in full-term infants while showing no relation to any measurements in premature infants. CONCLUSION: The study demonstrated the very low skin hydration levels in hospitalized neonates, particularly in premature neonates with more susceptible skin hydration instability despite therapeutic interventions for fluid balance. More vigilant fluid management is imperative in neonates, particularly those in the open environment.


Assuntos
Água Corporal/metabolismo , Epiderme/metabolismo , Fenômenos Fisiológicos da Pele , Demografia , Feminino , Humanos , Incubadoras para Lactentes , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Fototerapia/métodos , Perda Insensível de Água
14.
Taehan Kanho Hakhoe Chi ; 35(7): 1401-9, 2005 Dec.
Artigo em Coreano | MEDLINE | ID: mdl-16418567

RESUMO

PURPOSE: Infants at neonatal intensive care units (NICU) are invariably exposed to various procedural and environmental stimuli. The study was performed to compare the pain responses in three NICU stimulants and to examine the clinical feasibility for NICU infants using CRIES, FLACC and PIPP. METHOD: In a correlational study, a total of 94 NICU stimulants including angio-catheter insertions, trunk-rubbings and loud noises, was observed for pain responses among 64 infants using CRIES, FLACC and PIPP. RESULTS: A significant difference was identified among the mean scores in CRIES (F(2, 91)=47.847, p=.000), FLACC (F(2, 91)=41.249, p=.000) and PIPP (F(2, 91)=16.272, p=.000) to three stimulants. In a Post-hoc Scheff test, an angio-catheter insertion showed the highest scores in CRIES, FLACC and PIPP compared to the other two stimulations. A strong correlation was identified between CRIES and FLACC in all three stimulations (.817 < r < .945) while inconsistent findings were identified between PIPP and CRIES or FLACC. CONCLUSIONS: The results of the study support that CRIES and FLACC are reliable and clinically suitable pain measurements for NICU infants. Further studies are needed in data collection time-point as well as clinical feasibility on PIPP administration to assess pain response in infants, including premature infants.


Assuntos
Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Medição da Dor/métodos , Feminino , Humanos , Comportamento do Lactente , Masculino
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