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1.
Appl Biochem Biotechnol ; 193(12): 4068-4082, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34542820

RESUMO

Bee venom is a medicinal product that is widely used in traditional therapies owing to its excellent anti-inflammatory activity. However, the use of bee venom has shown adverse effects. Therefore, there is a need for research that can remove the cytotoxicity of bee venom and enhance its efficacy. In this study, we hydrolyzed melittin, the main component of bee venom, and removed the other components to eliminate the toxicity of bee venom. To compare the efficacy of bee venom and detoxified bee venom, we examined their antioxidant effects using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. In addition, cytotoxicity was confirmed in MCF 10A and RAW 264.7 cells, using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt (MTS) assay. Detoxified bee venom showed a strong antioxidant activity and decreased a cytotoxicity in MCF 10A and RAW 264.7 cells. The anti-inflammatory activity of detoxified bee venom and bee venom were assessed by comparison of the expression of inflammatory cytokine mRNA and phosphorylation of IκBα in RAW 264.7 cells. Degranulation in RBL-2H3 cells was analyzed through ß-hexosaminidase release assay to confirm the allergenic activity of bee venom and detoxified bee venom. Treatment of the detoxified bee venom inhibited inflammatory cytokine mRNA expression, IκBα phosphorylation, and ß-hexosaminidase release. Taken together, the results indicated that compared to bee venom, detoxified bee venom exhibited decreased cytotoxicity and allergenicity and increased anti-inflammatory activity. In conclusion, detoxification of bee venom efficiently decreases the adverse effects, making it suitable for medicinal applications.


Assuntos
Anti-Inflamatórios , Meliteno , Alérgenos/química , Alérgenos/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Citotoxinas/química , Citotoxinas/farmacologia , Feminino , Humanos , Meliteno/química , Meliteno/farmacologia , Camundongos , Células RAW 264.7
2.
PLoS One ; 14(5): e0216474, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31120917

RESUMO

A 26-GHz transmitter front-end is designed using 65 nm CMOS technology. The double frequency conversion transmitter consists of an intermediate frequency(IF) mixer, an millimeter-wave(mm-wave) mixer, and a pre-power amplifier. A double quadrature architecture is employed to accomplish image rejection without using an image rejection filter for the first time in the mm-wave frequency band. The IF mixer cores are designed as harmonic rejection mixers to avoid using IF filters. The measured conversion gain is 26.85±0.65 dB, with LO2 (IF LO) at 1-1.5 GHz and 26.9±0.6 dB with LO1 (mm-wave LO) at 27-29 GHz. The measured output return loss is less than -10 dB at 25.7-27.2 GHz. The output 1-dB compression point and the saturation output power measured at 26 GHz are 10 dBm and 14.1 dBm, respectively. The output-referred third-order intercept point (OIP3) measured at 26 GHz is 15.76 dBm. The third-order distortion, suppressed by the harmonic rejection mixer, is -60.5 dBc at an output power of 10 dBm. The error vector magnitude measured for OFDM 16-QAM with a 110-MHz signal bandwidth is -17.7 dB at an average output power of 3.5 dBm. The total power consumption of the proposed 26-GHz transmitter front-end is 267 mW, and it occupies a chip area of 2.31 mm2.


Assuntos
Amplificadores Eletrônicos , Ondas de Rádio , Tecnologia sem Fio
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 134: 184-90, 2015 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-25011045

RESUMO

Proton-substitution effects of 4-hydroxy-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-6-one (HPPCO) on structural and photophysical properties were presented. HPPCO crystallized in the orthorhombic space group Pbca with an intermolecular hydrogen bonding between OH and oxygen atom of the carbonyl. The proton-substituted derivatives, 6-oxo-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-4-yl acetate (OPPCA) and 6-oxo-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-4-yl benzoate (OPPCB), crystallized in the monoclinic P21/c space group. For OPPCA and OPPCB, a weak interaction between carbonyl oxygen atom in the substituted group and carbon atom in the fused ring was responsible for three-dimensional arrangements. In addition, 6-oxo-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-4-yl furan-2-carboxylate (OPPCF), and 6-oxo-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-4-yl naphthoate (OPPCN) were also synthesized. HPPCO and the four derivatives excited by ultraviolet (UV) light produced blue emission. Proton substitution of the OH group significantly increased the radiative transitions and moderately decreased the non-radiative transitions. Consequently the luminescence quantum yields of the derivatives enhanced more than 4.6-fold, no matter what the groups were substituted. Structural and optical properties were further determined using density functional theory (DFT) and ZINDO calculations. The planar structure of the pyridocarbazole-fused ring resulted in π→π(*) electronic transitions within the main frame, with an additional transition from the n(O) of carbonyl to the π(*) of the main frame. The three excited states that arose from these transitions were responsible for the blue luminescence.


Assuntos
Carbazóis/química , Medições Luminescentes/métodos , Modelos Moleculares , Piridinas/química , Técnicas de Química Sintética , Cristalografia por Raios X , Modelos Químicos , Estrutura Molecular , Prótons , Relação Estrutura-Atividade
4.
ACS Appl Mater Interfaces ; 6(12): 9053-60, 2014 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-24824186

RESUMO

The fabrication of well-ordered metal nanoparticle structures onto a desired substrate can be effectively applied to several applications. In this work, well-ordered Ag nanoparticle line arrays were printed on the desired substrate without the use of glue materials. The success of the method relies on the assembly of Ag nanoparticles on the anisotropic buckling templates and a special transfer process where a small amount of water rather than glue materials is employed. The anisotropic buckling templates can be made to have various wavelengths by changing the degree of prestrain in the fabrication step. Ag nanoparticles assembled in the trough of the templates via dip coating were successfully transferred to a flat substrate which has hydrophilic surface due to capillary forces of water. The widths of the fabricated Ag nanoparticle line arrays were modulated according to the wavelengths of the templates. As a potential application, the Ag nanoparticle line arrays were used as SERS substrates for various probing molecules, and an excellent surface-enhanced Raman spectroscopy (SERS) performance was achieved with a detection limit of 10(-12) M for Rhodamine 6G.


Assuntos
Nanopartículas Metálicas/química , Rodaminas/isolamento & purificação , Prata/química , Análise Espectral Raman , Limite de Detecção , Rodaminas/química , Propriedades de Superfície
5.
Microsc Microanal ; 19 Suppl 5: 145-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23920194

RESUMO

The growth of high-quality indium (In)-rich In(X)Ga(1-X)N alloys is technologically important for applications to attain highly efficient green light-emitting diodes and solar cells. However, phase separation and composition modulation in In-rich In(X )Ga(1-X)N alloys are inevitable phenomena that degrade the crystal quality of In-rich In(X)Ga(1-X)N layers. Composition modulations were observed in the In-rich In(X)Ga(1-X)N layers with various In compositions. The In composition modulation in the In X Ga1-X N alloys formed in samples with In compositions exceeding 47%. The misfit strain between the InGaN layer and the GaN buffer retarded the composition modulation, which resulted in the formation of modulated regions 100 nm above the In(0.67)Ga(0.33)N/GaN interface. The composition modulations were formed on the specific crystallographic planes of both the {0001} and {0114} planes of InGaN.

6.
Indian J Orthop ; 47(3): 244-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23798754

RESUMO

BACKGROUND: Large lumbar disc herniation (LDH) has been reported to have a greater tendency to resolve in clinical and pathomorphological evolutions. However, various definitions of large LDH have been used without validation, and the clinical symptoms of large LDH have not been fully elucidated. We conducted a retrospective analysis to determine the clinical characteristics and treatment outcome of massive LDH with complete dural sac stenosis. MATERIALS AND METHODS: We retrospectively reviewed 33 cases of LDH with complete dural sac stenosis on magnetic resonance imaging. Complete dural sac stenosis was defined as no recognizable rootlet and cerebrospinal fluid signal on T2-weighed axial MR images. The clinical outcome parameters included back pain, leg pain, Oswestry disability index (ODI), and neurological dysfunction. The paired t-test and Wilcoxon's signed rank test were used to compare serial changes in back pain, leg pain and neurological dysfunction. RESULTS: Mean duration of followup was 66 months (range 24 - 108 months). There were 24 male and 9 female. The mean age was 37 years (range 20 - 53 years). At presentation, mean visual analogue scales for back pain and leg pain were 75.3 ± 19.1 (range 12 - 100) and 80.2 ± 14.6 (range 0 -100), respectively. Mean ODI was 67.1 ± 18.8 (range 26 - 88). Neurological dysfunction was found in 9 patients (27.3%), and the bowel/bladder dysfunction was found in 2 patients (3.1%). Conservative treatment was performed in 21 patients (63.6%) with satisfactory results. Seven patients underwent decompressive surgery, and 5 underwent posterolateral fusion. CONCLUSIONS: A massive LDH with complete dural sac stenosis was found to be associated with severe back and leg pain at presentation, however surgical treatment can be deferred unless significant neurological symptoms occur.

7.
J Nanosci Nanotechnol ; 12(2): 1328-31, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22629949

RESUMO

Controlling the dimensions, positioning, and shapes of semiconductor nanowires, nanorods, and nanobelts lies in the synthesis and understanding of their growth mechanism. Controlled growth and synthesis is required in the fabrication of nanodevices and nanosensors. Among methods utilized for one-dimensional nanostructure synthesis, the hydrothermal process--a simple and cost-effective technique involving a low process temperature--has emerged as a powerful tool for the fabrication of anisotropic nanomaterials. Under hydrothermal conditions, many starting materials can undergo quite unexpected reactions, which are often accompanied by the formation of nanoscopic morphologies that are not accessible by classical routes. Synthesized ZnO nanostructures from aqueous solutions are usually poor in terms of morphology and size control. To improve the growth conditions and the controllability of the process, the use of surfactants or organic solvents has been attempted. In the present work, ZnO nanorods were grown on templates with a pre-sputtered ZnO seed layer over oxidized Si (100) substrates, and polyvinyl pyrrolidone (PVP) was used as a surfactant. By varying the PVP concentration in the growth solution, we can control the diameter and density of ZnO nanorods. The optical property of ZnO nanorods is highly improved by PVP addition.

8.
World J Pediatr ; 8(2): 169-72, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22573428

RESUMO

BACKGROUND: This study was undertaken to evaluate the association of the E23K polymorphism of KCNJ11 and type 1 diabetes in a Korean population. METHODS: Clinical variables from 70 Korean children with type 1 diabetes were analyzed. Patients' DNA was screened for the E23 locus in the KCNJ11 gene. Each genotype frequency and clinical characteristics according to the genotypes were compared between the patient and control groups. RESULTS: The genotype frequencies of the KCNJ11 E23 polymorphic locus in the patient group were 30.0% for EE, 44.3% for EK, and 25.7% for KK. We detected no differences in genotype frequencies between the patient and control groups. Additionally, in the patient group, no difference was detected in the clinical phenotypes among the three genotypes. CONCLUSION: Although a rather small sample size constituted a limitation of this study, the association of the E23K polymorphism with type 1 diabetes was not statistically significant in the Korean population evaluated.


Assuntos
Diabetes Mellitus Tipo 1/genética , Polimorfismo Genético , Canais de Potássio Corretores do Fluxo de Internalização/genética , Adolescente , Feminino , Humanos , Coreia (Geográfico) , Masculino , Estudos Retrospectivos
10.
Photochem Photobiol Sci ; 10(8): 1338-45, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21681309

RESUMO

A detailed photophysical analysis of 4-hydroxy-5-phenylpyrido[3,2,1-jk]carbazol-6-one (HPPCO) is presented. When exposed to UV light, the compound produced deep blue to green luminescence, depending on the solvent. The luminescence peak shifts with the Gutmann donor number (DN) of the solvent and the proton substitution affects luminescence; a correlation between quantum yield and decay time indicated that proton transfer plays a key role in the observed solvatochromism. The ground-state deprotonation of HPPCO was apparently evidenced from the absorption and/or the excitation spectra in the solvents with large DN values. DFT and ZINDO calculations on the structural and optical properties have shown that deprotonation increases the contribution of oxygen atoms to the HOMO, thereby lowering the transition energy from the HOMO to the LUMO. Because the luminescence properties of HPPCO depend on proton transfer, it may be used to detect and quantitate amines in solution. The sensitivity of the luminescence to various amines was ∼10(5) M(-1) and was more effective in ethanol than in methanol.

11.
Horm Res Paediatr ; 75(3): 174-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20881364

RESUMO

BACKGROUND/AIMS: Much concern has been raised and debated on the effects of obesity and bone mineral density (BMD) after treatment with GnRH agonist. The aim of this study was to assess BMD and body composition, especially percent body fat (%FM) based on dual-energy X-ray absorptiometry (DEXA), before and after 1 year of treatment with GnRH agonist in Korean girls. METHODS: We assessed BMD and body composition in 121 Korean girls with precocious puberty before and after 1 year of treatment with GnRH agonist. BMD and body composition values were measured by using DEXA. RESULTS: The BMD standard deviation score of each region of interest for chronological age (CA) were higher than zero, but lower than zero for bone age (BA) at baseline and the gap was decreased after 1 year of GnRH agonist treatment. The fat mass (FM) and %FM for both CA and BA were significantly higher than zero at baseline. After GnRH agonist treatment, FM and %FM decreased for CA, but increased for BA. CONCLUSION: Pituitary-gonadal axis suppression by GnRH agonist does not reverse the progression of bone mass acquisition and does not increase the prevalence of obesity in Korean children with precocious puberty.


Assuntos
Composição Corporal/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/agonistas , Puberdade Precoce/tratamento farmacológico , Absorciometria de Fóton , Adiposidade , Determinação da Idade pelo Esqueleto , Envelhecimento , Índice de Massa Corporal , Reabsorção Óssea/complicações , Reabsorção Óssea/epidemiologia , Criança , Pré-Escolar , Feminino , Hormônio Liberador de Gonadotropina/efeitos adversos , Humanos , Prontuários Médicos , Obesidade/complicações , Obesidade/epidemiologia , Prevalência , Puberdade Precoce/complicações , República da Coreia/epidemiologia , Estudos Retrospectivos
12.
Endocr J ; 57(8): 701-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20631455

RESUMO

Mutations in the GPR54 gene have already been identified as a cause of idiopathic hypogonadotrophic hypogonadism and central precocious puberty (CPP) in certain patients. However, currently there is only a limited amount of data available regarding KISS1 gene mutations or polymorphisms. The aim of this study is to identify KISS1 gene mutations or polymorphisms in Korean girls with CPP. 101 Korean girls with CPP were recruited as the patient group, and 51 healthy Korean female adults as the control group. All coding exons and exon-intron boundaries of the KISS1 gene were sequenced. The relationships between identified sequence variations and CPP were evaluated via the comparison of allele frequencies between the two groups. Different clinical characteristics were also compared between the subgroups with or without a certain variation in the patient group. Eight polymorphisms were identified in the KISS1 gene. Although two of them were novel, those polymorphisms could not lead to amino acid changes. p.P110T was detected less frequently in CPP patients than in the controls (P = 0.022). Moreover, the CPP patients with p.P110T evidenced lower peak FSH values under GnRH stimulation than those without p.P110T (P = 0.002). The allele frequencies of several polymorphisms in the Korean population were identified in this study. An infrequent polymorphism in the KISS1 gene, p.P110T, appeared to be meaningful. This polymorphism was suggested to exert a protective effect on pubertal precocity, even though more evidence will be required to confirm the accurate function.


Assuntos
Polimorfismo Genético/genética , Puberdade Precoce/genética , Proteínas Supressoras de Tumor/genética , Adolescente , Adulto , Sequência de Bases , Criança , DNA/análise , Éxons/genética , Feminino , Hormônio Foliculoestimulante/sangue , Frequência do Gene , Hormônio Liberador de Gonadotropina , Humanos , Íntrons/genética , Kisspeptinas , Hormônio Luteinizante/sangue , Reação em Cadeia da Polimerase , República da Coreia , Análise de Sequência de DNA , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/fisiologia
13.
Eur J Pediatr ; 169(4): 501-4, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19701813

RESUMO

Virilizing adrenocortical carcinoma and Turner syndrome have opposite clinical manifestations in some aspects. Here, we report on the first case of virilizing adrenocortical carcinoma in a girl with Turner syndrome. A 2 10/12-year-old girl presented pubic hair of Tanner stage III with clitomegaly, deepening of her voice, and tall stature. No other morphologic anomaly was found. Biochemical assessment revealed normal electrolytes with pronounced elevation of adrenal androgens. She was found to have a large mass of the left adrenal gland on abdominal computed tomography scan. She underwent complete resection of the mass, and pathology was consistent with adrenocortical carcinoma. She was tested for TP53 gene mutation, and we found a de novo TP53 gene mutation (Val143Ala) as well as a 45,X karyotype.


Assuntos
Carcinoma Adrenocortical/complicações , Carcinoma Adrenocortical/genética , Genes p53 , Mutação Puntual/genética , Síndrome de Turner/complicações , Virilismo/genética , Criança , Feminino , Humanos
14.
Med Hypotheses ; 72(2): 174-7, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18976868

RESUMO

Many theories have been postulated to date regarding mechanisms involved in non-enlargement of the subarachnoid space and enlargement of the ventricles in patients with communicating hydrocephalus, but none have been prove to be definite. Cerebrospinal fluid (CSF) movement is known not to bulk flow but rather pulsatile flow that develops from the energy of the blood flow ejected from the heart, in an isolated system of the intracranial cavity surrounded by a solid skull, as in the Monro-Kellie hypothesis. The authors attempt to explain the mechanisms involved in selective enlargement of the lateral ventricle in patients with communicating hydrocephalus by re-addressing the Monro-Kellie hypothesis with respect to cardiac energy transfer and dissipation by the Windkessel effect. The authors present a concept whereby the large energy of blood flow from the heart that is conveyed to the intracranial artery, arteriole, brain parenchyme, ventricle, and CSF within the confined cranial space as in the Monro-Kellie hypothesis, and which ultimately dissipates to maintain an intracranial energy equilibrium. In the same context, if, for some reason the intracranial equilibrium in the energy transfer and dissipation is changed or disrupted, then structural changes would have to occur to achieve and maintain a new intracranial equilibrium. We postulate that the above described mechanisms are those responsible for the development enlarged of lateral ventricles in patients with communicating hydrocephalus. Structural enlargement of the lateral ventricles in communicating hydrocephalus is a consequence of CSF pathway obstruction and resultantly increased CSF absorption function in the lateral ventricle which markedly increases the pulsatile CSF energy flow returning to the lateral ventricles, thus causing collision of pulsatile CSF flow with the brain parenchyme at the ventricular wall, which subsequently leads to structural enlargement of the lateral ventricles. Also, the collision between the CSF pulsation and brain parenchyme pulsation reduces the Windkessel effect of the brain parenchyme which increases the intracranial artery pulse pressure, which in turn is transmitted to the CSF and increases CSF pulse pressure. This vicious circle results in the high pulse pressure within the lateral ventricle structurally dilating the lateral ventricle. Our theory also explains the relationship between ventricle dilatation and idiopathic intracranial hypertension, venous sinus thrombosis, achondroplasia.


Assuntos
Transferência de Energia/fisiologia , Hidrocefalia/etiologia , Doenças Arteriais Intracranianas/fisiopatologia , Ventrículos Laterais/irrigação sanguínea , Ventrículos Laterais/fisiopatologia , Humanos , Hidrocefalia/fisiopatologia , Modelos Biológicos
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