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1.
Sci Rep ; 13(1): 11847, 2023 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-37481612

RESUMO

The purpose of this study was to propose the concept of software-based automated evaluation (SAE) of tooth preparation quality using computational geometric algorithms, and evaluate the feasibility of SAE in the assessment of abutment tooth preparation for single-unit anatomic contour crowns by comparing it with a human-based digitally assisted evaluation (DAE) by trained human evaluators. Thirty-five mandibular first molars were prepared for anatomical contour crown restoration by graduate students. Each prepared tooth was digitized and evaluated in terms of occlusal reduction and total occlusal convergence using SAE and DAE. Intra-rater agreement for the scores graded by the SAE and DAE and inter-rater agreement between the SAE and DAE were analyzed with the significance level (α) of 0.05. The evaluation using the SAE protocol demonstrated perfect intra-rater agreement, whereas the evaluation using the DAE protocol showed moderate-to-good intra-rater agreement. The evaluation values of the SAE and DAE protocols showed almost perfect inter-rater agreement. The SAE developed for tooth preparation evaluation can be used for dental education and clinical skill feedback. SAE may minimize possible errors in the conventional rating and provide more reliable and precise assessments than the human-based DAE.


Assuntos
Algoritmos , Software , Humanos , Estudos de Viabilidade , Competência Clínica , Coroas
2.
Adv Mater ; 33(44): e2105199, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34569647

RESUMO

Practical sensing applications such as real-time safety alerts and clinical diagnoses require sensor devices to differentiate between various target molecules with high sensitivity and selectivity, yet conventional devices such as oxide-based chemo-resistive sensors and metal-based surface-enhanced Raman spectroscopy (SERS) sensors usually do not satisfy such requirements. Here, a label-free, chemo-resistive/SERS multimodal sensor based on a systematically assembled 3D cross-point multifunctional nanoarchitecture (3D-CMA), which has unusually strong enhancements in both "chemo-resistive" and "SERS" sensing characteristics is introduced. 3D-CMA combines several sensing mechanisms and sensing elements via 3D integration of semiconducting SnO2 nanowire frameworks and dual-functioning Au metallic nanoparticles. It is shown that the multimodal sensor can successfully estimate mixed-gas compositions selectively and quantitatively at the sub-100 ppm level, even for mixtures of gaseous aromatic compounds (nitrobenzene and toluene) with very similar molecular structures. This is enabled by combined chemo-resistive and SERS multimodal sensing providing complementary information.


Assuntos
Nanopartículas Metálicas
3.
Front Microbiol ; 12: 752535, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35095785

RESUMO

Metallo-ß-lactamases (MBLs) hydrolyze almost all ß-lactam antibiotics, including penicillins, cephalosporins, and carbapenems; however, no effective inhibitors are currently clinically available. MBLs are classified into three subclasses: B1, B2, and B3. Although the amino acid sequences of MBLs are varied, their overall scaffold is well conserved. In this study, we systematically studied the primary sequences and crystal structures of all subclasses of MBLs, especially the core scaffold, the zinc-coordinating residues in the active site, and the substrate-binding pocket. We presented the conserved structural features of MBLs in the same subclass and the characteristics of MBLs of each subclass. The catalytic zinc ions are bound with four loops from the two central ß-sheets in the conserved αß/ßα sandwich fold of MBLs. The three external loops cover the zinc site(s) from the outside and simultaneously form a substrate-binding pocket. In the overall structure, B1 and B2 MBLs are more closely related to each other than they are to B3 MBLs. However, B1 and B3 MBLs have two zinc ions in the active site, while B2 MBLs have one. The substrate-binding pocket is different among all three subclasses, which is especially important for substrate specificity and drug resistance. Thus far, various classes of ß-lactam antibiotics have been developed to have modified ring structures and substituted R groups. Currently available structures of ß-lactam-bound MBLs show that the binding of ß-lactams is well conserved according to the overall chemical structure in the substrate-binding pocket. Besides ß-lactam substrates, B1 and cross-class MBL inhibitors also have distinguished differences in the chemical structure, which fit well to the substrate-binding pocket of MBLs within their inhibitory spectrum. The systematic structural comparison among B1, B2, and B3 MBLs provides in-depth insight into their substrate specificity, which will be useful for developing a clinical inhibitor targeting MBLs.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32825072

RESUMO

The factors related to oral healthcare service utilization (OHSU) among Korean adults aged 25-79 years were assessed using the Andersen model with the sixth Korean National Health and Nutrition Examination Survey data. The study included 12,937 participants aged 25-79 years who answered questions on the predisposing, enabling, and need factors related to OHSU at dental clinics within the past 1 year. Age, sex, and education level were selected as predisposing factors; household income, residence region, and national and private health insurance status as enabling factors; and self-perceived oral health, dental pain, chewing status, and discomfort while speaking as need factors. These factors were assessed using multivariable complex logistic regression models. OHSU at dental clinics within the past 1 year was lower among less-educated participants, those with low, middle-low, and middle-high household income levels, rural participants, those benefiting from the Medicaid system, and non-insured participants. OHSU was higher among older participants, those who rated their self-perceived oral health status as bad, those with experience of dental pain, and those who experienced discomfort while chewing and speaking. The need factors were the most influential. Thus, interventions to reduce inequalities in OHSU are required to promote oral health for all.


Assuntos
Assistência Odontológica , Saúde Bucal , Aceitação pelo Paciente de Cuidados de Saúde , Adulto , Idoso , Estudos Transversais , Humanos , Pessoa de Meia-Idade , Inquéritos Nutricionais , República da Coreia , Fatores Socioeconômicos
5.
Environ Sci Pollut Res Int ; 27(36): 44951-44968, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32772293

RESUMO

The study investigates the correlation of CO2 absorption performance and electrical properties in a tri-ethanolamine (TEA) aqueous solution compared to the mono-ethanolamine (MEA) and di-ethanolamine (DEA) systems. While the absorption rate of the MEA and DEA systems varies with amine concentration, and the maximum rate is observed at 30.0 and 50.4 wt% amine solution, respectively, the rate of the TEA system according to concentration follows a parabolic curve and the maximum rate is observed at 15.0 wt% solution. The ionic conductivity of carbamic acid in the TEA system is estimated to be the smallest with 37.60 S cm2/mol z and the decreasing ratio of ionic activity coefficient according to the concentration is the largest. The results are mostly attributed to differences in amine molecular structure and the unique reaction mechanism. Finally, based on these values, the correlation equations are obtained to estimate CO2 absorption capacity by measuring electrical conductivity in situ.


Assuntos
Dióxido de Carbono , Etanolamina , Aminas , Água
6.
Arch Biochem Biophys ; 692: 108544, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32822639

RESUMO

Rapamycin is a clinically important macrolide agent with immunosuppressant and antiproliferative properties, produced by the actinobacterium, Streptomyces rapamycinicus. Two cytochrome P450 enzymes are involved in the biosynthesis of rapamycin. CYP107G1 and CYP122A2 catalyze the oxidation reactions of C27 and C9 of pre-rapamycin, respectively. To understand the structural and biochemical features of P450 enzymes in rapamycin biosynthesis, the CYP107G1 and CYP122A2 genes were cloned, their recombinant proteins were expressed in Escherichia coli, and the purified enzymes were characterized. Both enzymes displayed low spin states in the absolute spectra of ferric forms, and the titrations with rapamycin induced type I spectral changes with Kd values of 4.4 ± 0.4 and 3.0 ± 0.3 µM for CYP107G1 and CYP122A2, respectively. The X-ray crystal structures of CYP107G1 and its co-crystal complex with everolimus, a clinical rapamycin derivative, were determined at resolutions of 2.9 and 3.0 Å, respectively. The overall structure of CYP107G1 adopts the canonical scaffold of cytochrome P450 and possesses large substrate pocket. The distal face of the heme group is exposed to solvents to accommodate macrolide access. When the structure of the everolimus-bound CYP107G1 complex (CYP107G1-Eve) was compared to that of the ligand-free CYP107G1 form, no significant conformational change was observed. Hence, CYP107G1 has a relatively rigid structure with versatile loops to accommodate a bulky substrate. The everolimus molecule is bound to the substrate-binding pocket in the shape of a squeezed donut, and its elongated structure is bound perpendicular to a planar heme plane and I-helix.


Assuntos
Proteínas de Bactérias/química , Sistema Enzimático do Citocromo P-450/química , Streptomyces/enzimologia , Proteínas de Bactérias/genética , Cristalografia por Raios X , Sistema Enzimático do Citocromo P-450/genética , Domínios Proteicos , Estrutura Secundária de Proteína , Proteínas Recombinantes , Sirolimo/metabolismo , Streptomyces/genética
7.
ACS Nano ; 14(1): 1166-1175, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31904220

RESUMO

Dynamic high-resolution wavefront modulation of light is a long-standing quest in photonics. Metasurfaces have shown potential for realizing light manipulation with subwavelength resolution through nanoscale optical elements, or metaatoms, to overcome the limitations of conventional spatial light modulators. State-of-the-art active metasurfaces operate via phase modulation of the metaatoms, and their inability to also independently control the scattered amplitude leads to an inferior reconstruction of the desired wavefronts. This fundamental problem posed severe performance limitations particularly for applications relying on subwavelength spatiotemporal complex field modulation, which includes dynamic holography, high-resolution imaging, optical tweezing, and optical information processing. Here, we present the "metamolecule" strategy, which incorporates two independent subwavelength scatterers composed of noble metal antennas coupled to gate-tunable graphene plasmonic nanoresonators. The two-parametric control of the metamolecule secures the complete control of both amplitude and phase of light, enabling 2π phase shift as well as large amplitude modulation including perfect absorption. We further develop a generalized graphical model to examine the underlying requirements for complete complex amplitude modulation, offering intuitive design guidelines to maximize the tunability in metasurfaces. To illustrate the reconfigurable capability of our designs, we demonstrate dynamic beam steering and holographic wavefront reconstruction in periodically arranged metamolecules.

8.
Sensors (Basel) ; 19(23)2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31816868

RESUMO

Electroencephalography (EEG) has relatively poor spatial resolution and may yield incorrect brain dynamics and distort topography; thus, high-density EEG systems are necessary for better analysis. Conventional methods have been proposed to solve these problems, however, they depend on parameters or brain models that are not simple to address. Therefore, new approaches are necessary to enhance EEG spatial resolution while maintaining its data properties. In this work, we investigated the super-resolution (SR) technique using deep convolutional neural networks (CNN) with simulated EEG data with white Gaussian and real brain noises, and experimental EEG data obtained during an auditory evoked potential task. SR EEG simulated data with white Gaussian noise or brain noise demonstrated a lower mean squared error and higher correlations with sensor information, and detected sources even more clearly than did low resolution (LR) EEG. In addition, experimental SR data also demonstrated far smaller errors for N1 and P2 components, and yielded reasonable localized sources, while LR data did not. We verified our proposed approach's feasibility and efficacy, and conclude that it may be possible to explore various brain dynamics even with a small number of sensors.


Assuntos
Encéfalo/patologia , Eletroencefalografia , Redes Neurais de Computação , Processamento de Sinais Assistido por Computador , Adulto , Algoritmos , Interfaces Cérebro-Computador , Simulação por Computador , Estudos de Viabilidade , Humanos , Aprendizado de Máquina , Distribuição Normal
9.
Annu Int Conf IEEE Eng Med Biol Soc ; 2018: 470-473, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30440436

RESUMO

Sleep spindle is a salient brain activity found in the sigma frequency range (11-16 Hz) during sleep stage 2. It has been demonstrated that sleep spindle is related to memory consolidation, neurodegenerative disease, and mental disorders. Slow wave activity (0.5-4 Hz) is the most prominent EEG activity during sleep and appears as a large, spontaneous synchronization of cortical neurons. The role of slow wave activity has been proposed to regulate synaptic strength and memory consolidation. Many studies have investigated the effect of acoustic stimuli during the sleep slow wave. However, there have been few studies which investigated an effect of acoustic stimulation during sleep spindle activity. In this study, we examined the neurophysiological effect of acoustic stimulation during sleep spindle activity. We delivered pink noise after the detection of sleep spindle, and surmised that acoustic stimulation after sleep spindle detection may preserve delta activity during ongoing sleep. Further, we observed suppression of the sleep spindle activity around the times of acoustic stimulation and evoked slow wave activity and theta band activity immediately after tone onset.


Assuntos
Estimulação Acústica , Consolidação da Memória , Sono/fisiologia , Adulto , Eletroencefalografia , Humanos , Masculino , Neurônios , Neurofisiologia
10.
Lab Anim Res ; 30(4): 161-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25628726

RESUMO

Onion peel contains a high concentration of quercetin and other flavonoids. In this study, the potential immune-enhancing effects of an onion peel water extract (OPE) supplement were investigated by the rat forced swimming test. OPE was prepared using hot water. Thirty-six male Sprague Dawley rats were fed a pellet diet for 1 week and were then randomly divided into six groups: normal control (NC), forced swimming control (FSC), positive control (quercetin 20 mg/kg), and three groups administered 4, 20, or 100 mg/kg of OPE. Oral drug administration was conducted daily for 4 weeks. All rats, except those of NC group, were forced to swim in water and were considered exhausted when they failed to rise to the water surface to breathe within a 7-s period. Blood lymphocyte counts, immune organ weights, histopathological analysis, and serum interferon (IFN)-γ, tumor necrosis factor (TNF)-α, and interleukin (IL)-12 levels were determined. OPE-treated rats consumed more food and had an increased thymic cortex to medulla ratio than that observed in FSC group rats (P<0.05). The area of the white pulp in the spleens of OPE-treated group rats was increased compared with that in FSC group rats (P<0.05). Furthermore, blood lymphocyte numbers and IFN-γ, TNF-α, and IL-12 concentrations were significantly higher in OPE-fed groups than in FSC group (P<0.05). These results suggest that an OPE supplement can improve the immune status by increasing the number of immune-related cells and specific cytokine levels.

11.
J Environ Manage ; 114: 512-9, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23183145

RESUMO

The present paper investigates the various features of NaOH aqueous solution when applied as an absorbent to capture carbon dioxide (CO(2)) emitted with relatively high concentration in the flue gas. The overall CO(2) absorption reaction was carried out according to consecutive reaction steps that are generated in the order of Na(2)CO(3) and NaHCO(3). The reaction rate and capture efficiency were strongly dependent on the NaOH concentration in the Na(2)CO(3) production range, but were constant in the NaHCO(3) production step, irrespective of the NaOH concentration. The amount of CO(2) absorbed in the solution was slightly less than the theoretical value, which was ascribed to the low trona production during the reaction and the consequent decrease in CO(2) absorption in the NaOH solution. The mass ratio of absorbed CO(2) that participated in the Na(2)CO(3), NaHCO(3), and trona production reactions was calculated to be 20:17:1, respectively.


Assuntos
Poluição do Ar/prevenção & controle , Dióxido de Carbono/química , Hidróxido de Sódio/química , Adsorção , Bicarbonatos/síntese química , Indústrias Extrativas e de Processamento
12.
Lab Anim Res ; 27(2): 177-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21826179

RESUMO

A male one year-old beagle dog with unilateral cryptorchism was presented for investigation of reduced appetite. Abdominal sonography and radiography demonstrated abnormal enlargement of the left testicle in the abdominal cavity. Both the retroperitoneal cryptorchid testicle and the other contralateral testicle were removed surgically. The retroperitoneal cryptorchid testicle was an enlarged, firm and bulging sphere mass. The cut surface revealed a homogeneous white color. The contralateral testicle in the scrotum showed an almost normal appearance. Histopathologically, the retroperitoneal cryptorchid testicle was diagnosed as a Sertoli cell tumor. This report describes a case of Sertoli cell tumor with cryptorchism in a beagle dog.

13.
Immunopharmacol Immunotoxicol ; 32(3): 357-63, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20095799

RESUMO

To investigate the antiallergic effect of the rhizome of Anemarrhena asphodeloides (AA, family Liliaceae), which was found to inhibit the mouse passive cutaneous anaphylaxis (PCA) reaction induced by the antigen-immunoglobulin E (IgE) complex in preliminary experiments, main steroidal saponins, timosaponins AIII, BIII, and D, were isolated and their inhibitory effects against PCA reaction and scratching behaviors investigated in mice. Oral administration of three main steroidal sapogenins blocked the PCA reaction and scratching behaviors, timosaponin AIII was the most potent. However, intraperitoneal administration of timosaponin AIII showed weak inhibition. To understand its metabolism and antiallergic mechanism, timosaponin AIII was anaerobically incubated with human intestinal microflora to afford a main metabolite, sarsasapogenin. Intraperitoneal administration of sarsasapogenin inhibited allergic reaction more potently than timosaponin AIII. In addition, sarsasapogenin more potently inhibited degranulation and IL-4 protein expression of RBL-2H3 cells induced by IgE-antigen complex than timosaponin AIII. On the basis of these findings, antiallergic effect of AA may be due to those of its steroidal constituents, and that of timosaponin AIII may be activated by using intestinal microflora.


Assuntos
Anemarrhena/química , Antialérgicos/administração & dosagem , Anafilaxia Cutânea Passiva/efeitos dos fármacos , Prurido/tratamento farmacológico , Rizoma/química , Saponinas/administração & dosagem , Saponinas/uso terapêutico , Esteroides/uso terapêutico , Anemarrhena/imunologia , Animais , Antialérgicos/química , Antialérgicos/isolamento & purificação , Complexo Antígeno-Anticorpo/efeitos dos fármacos , Células Cultivadas , Humanos , Imunoglobulina E/análise , Interleucina-4/análise , Intestinos/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Ratos , Ratos Sprague-Dawley , Rizoma/imunologia , Saponinas/química , Saponinas/isolamento & purificação , Espirostanos/administração & dosagem , Espirostanos/análise , Espirostanos/metabolismo , Esteroides/química , Esteroides/isolamento & purificação , Fator de Necrose Tumoral alfa/análise
14.
Int J Colorectal Dis ; 25(5): 545-51, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19956958

RESUMO

PURPOSE: In a preliminary study, we found that lancemaside A, which is a main constituent of Codonopsis lanceolata used as an herbal medicine for inflammatory diseases, potently inhibits lipopolysaccharide (LPS)-stimulated, TLR-4-linked NF-kappaB activation of NF-kappaB luciferase reporter gene-transfected 293-hTLR4-hemagglutinin (HA) cells. Therefore, we investigated its inhibitory effect in 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis in mice. METHODS: We measured the ability of lancemaside A to inhibit LPS-stimulated, TLR-4-linked NF-kappaB activation in human embryonic kidney (HEK) cells, as well as to inhibit colitis outcomes in TNBS-induced colitis in mice. We also measured levels of the inflammatory markers, interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha, and IL-6, and their transcription factor, NF-kappaB, in intestinal mucosa by enzyme-linked immunosorbent assay and immunoblotting. RESULT: Intrarectal treatment of TNBS in mice caused colon shortening and also increased colonic expression of IL-1beta, IL-6, and TNF-alpha expression. Oral administration of lancemaside A (10 and 20 mg/kg), inhibited colon shortening and myeloperoxidase activity in TNBS-induced colitic mice and also decreased colonic expression of IL-1beta, IL-6, and TNF-alpha. Lancemaside A inhibited NF-kappaB activation induced by TNBS, as well as the expression of cyclooxygenase 2 and TLR-4. Lancemaside A also reduced the activity of intestinal bacterial beta-glucuronidase that was induced by TNBS. CONCLUSIONS: Lancemaside A ameliorates colitis via inhibition of TLR-4-linked NF-kappaB activation.


Assuntos
Colite/tratamento farmacológico , NF-kappa B/metabolismo , Saponinas/uso terapêutico , Animais , Linhagem Celular , Colite/induzido quimicamente , Colite/enzimologia , Colite/patologia , Ciclo-Oxigenase 2/metabolismo , Citocinas/metabolismo , Fezes/enzimologia , Glucuronidase/metabolismo , Humanos , Ácido Hialurônico/metabolismo , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , NF-kappa B/antagonistas & inibidores , Saponinas/química , Saponinas/isolamento & purificação , Receptor 4 Toll-Like/metabolismo , Ácido Trinitrobenzenossulfônico
15.
Biol Pharm Bull ; 32(10): 1710-5, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19801832

RESUMO

To understand memory-enhancing effect of red ginseng biotransformed by Bifidobacterium longum H-1 (RGB), which more potently improved scopolamine-induced learning deficit than red ginseng in the preliminary experiment, its main constituents, ginsenosides Rb1, Rg3 and Rh2, were isolated and their memory-enhancing effects investigated in scopolamine-treated mice by using passive avoidance and Y-maze tests. Among them, ginsenoside Rh2 most potently reversed memory impairment caused by scopolamine. Ginsenoside Rh2 also significantly shortened the escape latencies prolonged by scopolamine in the Morris water maze test (p<0.001) and increased the swimming time shorten by scopolamine within the platform quadrant (p<0.05). The ginsenoside Rh2 (3 muM) reversed scopolamine (10 muM)-induced suppression of long-term potentiation. It recovered field excitatory post synaptic potential (fEPSP) amplitude potentiation to 152.3+/-8.7% of the control (p<0.05). Based on these findings, RGB and its main constituent, ginsenoside Rh2, might improve learning deficits. Also the memory-enhancing effects of RGB may be dependent on the content of ginsenoside Rh2.


Assuntos
Ginsenosídeos/uso terapêutico , Transtornos da Memória/tratamento farmacológico , Panax/química , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Comportamento Animal/efeitos dos fármacos , Bifidobacterium , Biotransformação , Modelos Animais de Doenças , Ginsenosídeos/isolamento & purificação , Ginsenosídeos/farmacologia , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Camundongos , Camundongos Endogâmicos ICR , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Escopolamina , Natação , Potenciais Sinápticos
16.
J Cosmet Dermatol ; 7(3): 189-93, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18789053

RESUMO

Arbutin, the beta-D-glucopyranoside of hydroquinone, is a skin whitening cosmetic ingredient. Compared with arbutin, hydroquinone is a more potent skin lightening agent, but shows cytotoxicity, nephrotoxicity, and genotoxicity. To evaluate whether skin microflora can hydrolyze arbutin to hydroquinone, we measured the hydrolytic activity of the main skin microflora: Staphylococcus epidermidis and Staphylococcus aureus. All strains hydrolyzed arbutin, with activities of 0.16-4.51 nmol/min/mg. The hydrolyzed hydroquinone showed more potent 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and tyrosinase inhibition than arbutin. These findings suggest that normal skin microflora may increase the skin lightening effect of arbutin due to the antioxidant action of hydroquinone.


Assuntos
Antioxidantes/farmacologia , Arbutina/farmacologia , Hidroquinonas/farmacologia , Pele/efeitos dos fármacos , Antioxidantes/metabolismo , Arbutina/metabolismo , Feminino , Humanos , Hidrólise/efeitos dos fármacos , Hidroquinonas/metabolismo , Melanócitos/efeitos dos fármacos , Melanócitos/metabolismo , Pele/metabolismo , Pele/microbiologia , Pigmentação da Pele/efeitos dos fármacos , Staphylococcus aureus/metabolismo , Staphylococcus epidermidis/metabolismo
17.
Planta Med ; 74(3): 210-4, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18300192

RESUMO

The anti-pruritic effect of red ginseng (the steamed root of Panax ginseng C.A. Meyer, Araliaceae), a traditional medicine in Asian countries, was investigated in mouse scratching behavior models induced by either compound 48/80 or histamine. Red ginseng and its saponin fraction, but not its polysaccharide fraction, showed an anti-pruritic effect. Representative constituents in the saponin fraction, ginsenosides Rg3 and Rh2, inhibited scratching behavior and vascular permeability. These ginsenosides also inhibited the expression of TNF-alpha and IL-4 induced by IgE-antigen complex in RBL-2H3 cells, as well as acetic acid-induced writhing in mice. These results suggest that red ginseng and its ingredients, ginsenosides Rg3 and Rh2, may inhibit scratching behavior by inhibiting IL-4 and TNF-alpha expression, promoting membrane stability, and inhibiting Ca (++) influx.


Assuntos
Antipruriginosos/análise , Ginsenosídeos/uso terapêutico , Panax/química , Fitoterapia , Prurido/tratamento farmacológico , Ácido Acético , Animais , Antipruriginosos/uso terapêutico , Ginsenosídeos/isolamento & purificação , Histamina , Imunoglobulina E , Interleucina-4/metabolismo , Camundongos , Extratos Vegetais/uso terapêutico , Raízes de Plantas/química , Prurido/induzido quimicamente , Ratos , Fator de Necrose Tumoral alfa/metabolismo , p-Metoxi-N-metilfenetilamina
18.
J Microbiol Biotechnol ; 17(7): 1127-33, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18051323

RESUMO

Antihyperlipidemic and antihyperglycemic effects of Red Ginseng (RG, steamed and dried root of Panax ginseng C. A. Meyer, family Araliaceae), major component of which is ginsenoside Rg3, and Bifidodoterium-fermented RG (FRG), major component of which is ginsenoside Rh2, were investigated. Orally administered RG and FRG potently reduced the serum triglyceride levels in corn-oil-induced hypertriglycemidemic mice as well as total cholesterol and triglyceride levels in Triton WR-1339-induced hyperlipidemic mice. Of the saponin and polysaccharide fractions of RG and FRG, the polysaccharide fraction inhibited postprandial blood glucose elevation of maltose- or starch-loaded mice and reduced the blood triglyceride levels in corn-oil-induced hypertriglycemidemic mice. The saponin fraction and its ginsenosides Rg3 and Rh2 reduced blood triglyceride and total cholesterol levels in Triton WR1339-induced hyperlipidemic mice. The inhibitory effect of FRG and its main constituents against hyperlipidemia and hyperglycemia in mice were more potent than those of RG. These findings suggest that hypolipidemic and hypoglycemic effects of RG can be enforced by Bifidus fermentation and FRG may improve hyperlipidemia and hyperglycemia.


Assuntos
Hipoglicemia/tratamento farmacológico , Hipolipemiantes/uso terapêutico , Panax , Fitoterapia , Extratos Vegetais/farmacologia , Administração Oral , Animais , Bifidobacterium/isolamento & purificação , Bifidobacterium/fisiologia , Colesterol/sangue , Relação Dose-Resposta a Droga , Fermentação , Ginsenosídeos/administração & dosagem , Ginsenosídeos/química , Ginsenosídeos/isolamento & purificação , Ginsenosídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Extratos Vegetais/química , Óleos de Plantas/farmacologia , Raízes de Plantas/química , Polietilenoglicóis/farmacologia , Polissacarídeos/farmacologia , Saponinas/química , Saponinas/farmacologia , Tensoativos/farmacologia , Triglicerídeos/sangue , Zea mays/química
19.
Biochem Pharmacol ; 74(11): 1642-51, 2007 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-17880928

RESUMO

Matrix metalloproteinases (MMPs) play an important role in glioma infiltration, facilitating cell migration and tumor invasion through their ability to degrade the extracellular matrix. Therefore, the inhibition of MMPs has been suggested to be a promising therapeutic strategy for brain tumors. This study examined the effect of ginsenoside Rh2 on the expression of MMPs in human astroglioma cells. Rh2 inhibited the PMA-induced mRNA expression of MMP-1, -3, -9, and -14, suggesting that Rh2 has a broad-spectrum inhibitory effect on MMPs. The molecular mechanism underlying MMP-9 inhibition was further investigated because MMP-9 plays a major role in the invasiveness of glioma. It was found that Rh2 inhibited the secretion and protein expression of MMP-9 induced by PMA in human astroglioma cells. The Rh2-mediated inhibition of MMP-9 gene expression appears to occur through NF-kappaB and AP-1 because their DNA binding and transcriptional activities were suppressed by the agent. Furthermore, Rh2 significantly repressed the PMA-mediated activation of p38 MAPK, ERK and JNK, which are upstream modulators of NF-kappaB and AP-1. Finally, Rh2 inhibited the in vitro invasiveness of glioma cells, which might be attributed to the broad-spectrum inhibition of MMPs by Rh2. Overall, the strong inhibition of MMP expression by Rh2 might provide a potential therapeutic modality for brain tumors.


Assuntos
Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Ginsenosídeos/farmacologia , Metaloproteinases da Matriz/genética , Astrocitoma/genética , Astrocitoma/metabolismo , Astrocitoma/patologia , Sítios de Ligação/genética , Western Blotting , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Proteínas de Ligação a DNA/metabolismo , Relação Dose-Resposta a Droga , Ensaio de Desvio de Mobilidade Eletroforética , Ginsenosídeos/química , Humanos , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 14 da Matriz/genética , Metaloproteinase 14 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/genética , Metaloproteinase 3 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Metaloproteinases da Matriz/metabolismo , Estrutura Molecular , NF-kappa B/metabolismo , Invasividade Neoplásica , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Acetato de Tetradecanoilforbol/farmacologia , Fator de Transcrição AP-1/metabolismo
20.
IEEE Trans Syst Man Cybern B Cybern ; 36(3): 559-70, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16761810

RESUMO

The process of learning the behavior of a given program by using machine-learning techniques (based on system-call audit data) is effective to detect intrusions. Rule learning, neural networks, statistics, and hidden Markov models (HMMs) are some of the kinds of representative methods for intrusion detection. Among them, neural networks are known for good performance in learning system-call sequences. In order to apply this knowledge to real-world problems successfully, it is important to determine the structures and weights of these call sequences. However, finding the appropriate structures requires very long time periods because there are no suitable analytical solutions. In this paper, a novel intrusion-detection technique based on evolutionary neural networks (ENNs) is proposed. One advantage of using ENNs is that it takes less time to obtain superior neural networks than when using conventional approaches. This is because they discover the structures and weights of the neural networks simultaneously. Experimental results with the 1999 Defense Advanced Research Projects Agency (DARPA) Intrusion Detection Evaluation (IDEVAL) data confirm that ENNs are promising tools for intrusion detection.


Assuntos
Algoritmos , Inteligência Artificial , Segurança Computacional , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão/métodos , Validação de Programas de Computador , Software , Evolução Biológica
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