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1.
ACS Appl Mater Interfaces ; 15(10): 13131-13143, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36791219

RESUMO

Problematic issues with electrically inert binders have been less serious in the conventional lithium-ion batteries by virtue of permeable liquid electrolytes (LEs) for ionic connection and/or carbonaceous additives for electronic connection in the electrodes. Contrary to electron-conductive binders used to maximize an active loading level, the development of ion-conductive binders has been lacking owing to the LE-filled electrode configuration. Herein, we represent a tactical strategy for improving the interfacial Li+ conduction in all-solid-state electrolyte-free graphite (EFG) electrodes where the solid electrolytes are entirely excluded, using lithium-substitution-modulated (LSM) binders. Finely tuning a lithium substitution ratio, a conductive LSM-carboxymethyl cellulose (CMC) binder is prepared from a controlled direct Na+/Li+ exchange reaction without a hazardous acid involvement. The EFG electrode employing LSM with a maximum degree of substitution of lithium (DSLi) of ∼68% in our study shows a considerably higher rate capability of 1.05 mA h cm-2 at 1 C and a capacity retention of ∼61.9% after 200 cycles at 0.5 C than those using sodium-CMC (Na-CMC) (0.78 mA h cm-2, ∼49.5%) and LSM with ∼35% lithium substitution (0.93 mA h cm-2, ∼55.4%). More importantly, the correlation between the phase transition near the bottom region of the EFG electrode and the state of charge (SOC) is systematically investigated, clarifying that the improvement of the interfacial conduction is proportional to the DSLi of the CMC binders. Theoretical calculations combined with experimental results further verify that creating the continuous interface through abundant pathways for mobile ions using the Li+-conductive binder is the enhancement mechanism of the interfacial conduction in the EFG electrode, mitigating serious charge transfer resistance.

2.
Opt Express ; 30(7): 11959-11972, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35473127

RESUMO

Even though it is in high demand to introduce a nano-structure (NS) light extraction technology on a silicon nitride to be used as a thin film encapsulation material for an organic light-emitting diode (OLED), only an industry-incompatible wet method has been reported. This work demonstrates a double-layer NS fabrication on the silicon nitride using a two-step organic vapor phase deposition (OVPD) of an industry-compatible dry process. The NS showed a wrinkle-like shape caused by coalescence of the nano-lenses. The NS integrated top-emitting OLED revealed 40 percent enhancement of current efficiency and improvement of the luminance distribution and color change according to viewing angle.

3.
Mater Horiz ; 8(11): 3141-3148, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34570854

RESUMO

In this study, it is shown that fluorinated azide, employed as a functional additive to photomultiplication-type organic photodiodes (PM-OPDs), can not only enhance the operational stability by freezing the morphology consisting of matrix polymer/localized acceptor but also stabilize the trapped electron states such that the photomultiplication mechanism can be accelerated further, leading to exceptionally high external quantum efficiency (EQE). The consequent semitransparent OPD consisting of molybdenum oxide (MoO3)/Au/MoO3/photoactive layer/polyethyleneimine ethoxylated/indium tin oxide (ITO) rendered a maximum EQE of over 500 000% and 370 000% under bottom and top illumination, respectively. Owing to the remarkably high EQE, high specific detectivity of 5.6 × 1013 Jones and low noise-equivalent power of 5.35 × 10-15 W Hz-0.5 were also demonstrated. Furthermore, the OPD demonstrated stable performance during 20 h of continuous operation and minimal performance degradation even after the damp heat test. To fully visualize the advantages of the proposed high-EQE, top-illuminated, semitransparent OPD with spectral asymmetry between absorption and detection, a reflection-type fingerprint platform consisting of 1 OPD-1 oxide field-effect transistor complementary metal-oxide-semiconductor backplane (300 ppi) is designed and fabricated. The successful recognition of the fingerprint of one of the authors is demonstrated, which indicates the feasibility of the proposed PM-OPD for sensing weak light intensity.

4.
Int J Surg Case Rep ; 59: 111-114, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31128547

RESUMO

INTRODUCTION: Adenomyoepithelioma of the breast is a rarely reported and mostly benign disease that seldom undergoes malignant transformation. PRESENTATION OF THE CASE: Here, we present a case of malignant adenomyoepithelioma of the breast in a patient who initially presented with pain following an excision procedure at local clinic. The condition was finally diagnosed after a third surgical procedure, pathologic analysis with hematoxylin and eosin staining, and immunohistochemistry analysis to detect smooth muscle actin and S100 expression. CONCLUSION: The patient developed no complications or recurrences after a total mastectomy with sentinel node dissection.

5.
Breast Cancer Res Treat ; 171(2): 501-511, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29915946

RESUMO

PURPOSE: We hypothesized that an increase in BMI category during neoadjuvant chemotherapy (NAC) would be associated with pathological complete response (pCR) rate and worse survival outcomes in primary breast cancer patients. METHODS: We reviewed the records of 4029 patients with stage I-III breast cancer who had undergone NAC and definitive surgery at our institution between May 1, 1990 and April 30, 2013. BMI values at baseline and after NAC were recorded, and the corresponding BMI category was assessed with the WHO classification. Overall survival (OS) and recurrence-free survival (RFS) were estimated using the Kaplan-Meier method, and multivariate Cox regression models were used to estimate the effect of covariates of interest on OS and RFS. RESULTS: The median follow-up period was 3.95 years. A change in BMI category from normal to obese during NAC was independently associated with shorter OS duration than was maintaining a normal weight [hazard ratio (HR) 1.637; 95%CI 1.066-2.514; p = 0.0242]. Kaplan-Meier curves among breast cancer subtypes showed differences, and a decrease in BMI led to better RFS and OS rates in obese patients with HR+/HER2- disease; those who maintained BMI also showed better prognosis for triple-negative breast cancer (TNBC). We saw no association between BMI change and pCR rate. CONCLUSION: Our data suggest that inability to maintain normal weight during NAC is a predictive marker of poor survival but not pCR. It may be important for patients to maintain a normal weight during NAC.


Assuntos
Índice de Massa Corporal , Neoplasias da Mama/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Quimioterapia Adjuvante , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Recidiva , Taxa de Sobrevida , Resultado do Tratamento
6.
ACS Appl Mater Interfaces ; 10(22): 18942-18947, 2018 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-29749737

RESUMO

Recently, we have addressed that a formation mechanism of a nanolens array (NLA) fabricated by using a maskless vacuum deposition is explained as the increase in surface tension of organic molecules induced by their crystallization. Here, as another research using finite difference time domain simulations, not electric field intensities but transmitted energies of electromagnetic waves inside and outside top-emitting blue organic light-emitting diodes (TOLEDs), without and with NLAs, are obtained, to easily grasp the effect of NLA formation on the light extraction of TOLEDs. Interestingly, the calculations show that NLA acts as an efficient light extraction structure. With NLA, larger transmitted energies in the direction from emitting layer to air are observed, indicating that NLAs send more light to air otherwise trapped in the devices by reducing the losses by waveguide and absorption. This is more significant for higher refractive index of NLA. Simulation and measurement results are consistent. A successful increase in both light extraction efficiency and color stability of blue TOLEDs, rarely reported before, is accomplished by introducing the highly process-compatible NLA technology using the one-step dry process. Blue TOLEDs integrated with a N, N'-di(1-naphthyl)- N, N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine NLA with a refractive index of 1.8 show a 1.55-times-higher light extraction efficiency, compared to those without it. In addition, viewing angle characteristics are enhanced and image blurring is reduced, indicating that the manufacturer-adaptable technology satisfies the requirements of highly efficient and color-stable top-emission displays.

7.
J Pharm Sci ; 107(7): 1831-1841, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29574229

RESUMO

N-glycans of therapeutic glycoproteins are critical quality attributes that should be monitored throughout all stages of biopharmaceutical development. To reduce both the time for sample preparation and the variations in analytical results, we have developed an N-glycan analysis method that includes improved 2-aminobenzoic acid (2-AA) labeling to easily remove deglycosylated proteins. Using this analytical method, 15 major 2-AA-labeled N-glycans of Enbrel® were separated into single peaks in hydrophilic interaction chromatography mode and therefore could be quantitated. 2-AA-labeled N-glycans were also highly compatible with in-line quadrupole time-of-flight mass spectrometry (MS) for structural identification. The structures of 15 major and 18 minor N-glycans were identified from their mass values determined by quadrupole time-of-flight MS. Furthermore, the structures of 14 major N-glycans were confirmed by interpreting the MS/MS data of each N-glycan. This analytical method was also successfully applied to neutral N-glycans of Humira® and highly sialylated N-glycans of NESP®. Furthermore, the analysis data of Enbrel® that were accumulated for 2.5 years demonstrated the high-level consistency of this analytical method. Taken together, the results show that a wide repertoire of N-glycans of therapeutic glycoproteins can be analyzed with high efficiency and consistency using the improved 2-AA labeling-based N-glycan analysis method.


Assuntos
Ácido 4-Aminobenzoico/análise , Adalimumab/química , Etanercepte/química , Glicoproteínas/química , Polissacarídeos/análise , Cromatografia Líquida de Alta Pressão , Humanos , Interações Hidrofóbicas e Hidrofílicas , Espectrometria de Massas , Proteínas Recombinantes/química , Coloração e Rotulagem
8.
J Breast Cancer ; 20(4): 340-346, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29285038

RESUMO

PURPOSE: The current multicenter phase II study was conducted to evaluate the efficacy and safety of the combination of docetaxel and gemcitabine as neoadjuvant chemotherapy (NAC) for locally advanced breast cancer. METHODS: A total of 98 patients with stage II-III breast cancer were enrolled. The primary endpoint was pathological complete response (pCR) rate of invasive cancer after the completion of the fourth cycle of NAC. The secondary endpoints included response rate (RR), rate of breast-conserving surgery, toxicity, and disease-free survival (DFS). This study is registered with ClinicalTrials.gov (NCT01352494). RESULTS: pCR in the breast and the axillary lymph node was observed in seven of the 98 enrolled patients (7.1%). The overall clinical RR, including partial responses, was 65.3%. Breast-conserving surgery was performed in 75 of the 98 assessable patients (76.5%). Neutropenia was frequent and was observed in 92 of the 98 patients (93.9%), including grade 3 and 4 in 24 patients (24.5%) and 63 patients (64.3%), respectively. Dose reductions were required for 30 of the 92 patients (32.6%). After a median follow-up of 24 months, the overall DFS of the group was 86.7%. CONCLUSION: The combination of docetaxel and gemcitabine did not improve pCR. However, this regimen has shown potential as a NAC by producing a reasonable rate of breast-conserving surgery and favorable responses in patients with locally advanced breast cancer. The therapeutic efficacy of this regimen will be determined in additional trials to overcome the limitations of the current study.

9.
Nanoscale ; 9(1): 230-236, 2017 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-27906406

RESUMO

To date, all deposition equipment has been developed to produce planar films. Thus lens arrays with a lens diameter of <1 mm have been manufactured by combining deposition with other technologies, such as masks, surface treatment, molding etc. Furthermore, a nano-lens array (NLA) with a sufficiently small lens diameter (<1 µm) is necessary to avoid image quality degradation in high resolution displays. In this study, an organic NLA made using a conventional deposition technique - without combining with other techniques - is reported. Very interestingly, grazing-incidence small-angle X-ray scattering (GI-SAXS) experiments indicate that the NLA is formed by the crystallization of organic molecules and the resulting increase in surface tension. The lens diameter can be tuned for use with any kind of light by controlling the process parameters. As an example of their potential applications, we use NLAs as a light extraction film for organic light emitting diodes (OLEDs). The NLA is integrated by directly depositing it on the top electrode of a collection of OLEDs. This is a dry process, meaning that it is fully compatible with the current OLED production process. Devices with NLAs exhibited a light extraction efficiency 1.5 times higher than devices without, which corresponds well with simulation results. The simulations show that this high efficiency is due to the reduction of the guided modes by scattering at the NLA. The NLAs also reduce image blurring, indicating that they increase color stability.

10.
Breast Cancer (Auckl) ; 10: 205-210, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27980416

RESUMO

INTRODUCTION: Recently, the incidence of ductal carcinoma in situ (DCIS), a noninvasive breast malignancy, has increased. This has resulted in an increase in the incidence of breast-conserving surgery (BCS). Numerous studies have suggested that intraoperative frozen section analysis (IFSA) could reduce the rate of additional excisions required to obtain adequate resection margins. However, DCIS is a known risk factor for positive margin status during BCS. Furthermore, some authors have concluded that IFSA may not be reliable for the detection of DCIS. AIM: The aim of this study was to evaluate the safety and efficacy of IFSA in patients with DCIS. METHODS: The operative and pathological reports of patients with DCIS, who underwent BCS at our institute between 2006 and 2015, were retrospectively reviewed. The results of IFSA and the pathological findings of final reanalyzed frozen tissue specimens were analyzed. RESULTS: In total, 25 patients were included in our analysis. None of the patients required additional operations. The correct diagnosis rate for IFSA was 89.6%, with a sensitivity and specificity of 60.0% and 95.8%, respectively. CONCLUSION: IFSA could be beneficial for determining safety resection margins in patients with DCIS.

11.
Vasc Specialist Int ; 31(1): 25-31, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26217641

RESUMO

PURPOSE: This study aimed to compare the efficacy of two different catheters in hybrid surgery for salvage of thrombosed hemodialysis accesses. MATERIALS AND METHODS: The hybrid salvage procedure (surgical thrombectomy followed by endovascular angioplasty) of the thrombosed hemodialysis access, was performed using adherent clot (AC) catheter in 140 cases and Fogarty balloon catheter in 68 cases. Procedure-related outcomes such as the clot removal status, clinical success, complications, and primary patency rates were analyzed retrospectively. RESULTS: The proportion of cases with good clot removal scores in the AC catheter and Fogarty balloon catheter groups was 77.9% and 91.2%, respectively (P=0.018). Clinical success was achieved in 90.7% of the cases in the AC catheter group and in 98.5% of the cases in the balloon catheter group (P=0.035). The mean patency rates of the two groups were 50.7% and 63.2% at 3 months, 40.7% and 47.1% at 6 months, and 17.9% and 19.1% at 12 months. The complication rates (12.1% and 5.9%) and primary patency rates between the two catheters were not statistically different (P=0.328). On the analysis of the patency rate on access type of autologous (P=0.169) and prothetic graft (P=0.423), there was no significant difference between the two catheter groups. CONCLUSION: In terms of clot removal and clinical success, the AC catheter did not demonstrate better outcomes than the Fogarty balloon catheter. However, primary patency was not related to the type of catheter. Adherent clot catheter can be a useful alternative to Fogarty balloon catheter for thrombosed hemodialysis access.

12.
J Nanosci Nanotechnol ; 13(12): 7801-5, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24266143

RESUMO

We fabricated a thermoelectric device with a silicide/silicon laminated hetero-structure by using RF sputtering and rapid thermal annealing. The device was observed to have Ohmic characteristics by I-V measurement. The temperature differences and Seebeck coefficients of the proposed silicide/silicon laminated and bulk structure were measured. The laminated thermoelectric device shows suppression of heat flow from the hot to cold side. This is supported by the theory that the atomic mass difference between silicide and silicon creates a scattering center for phonons. The major impact of our work is that phonon transmission is suppressed at the interface between silicide and silicon without degrading electrical conductivity. The estimated thermal conductivity of the 3-layer laminated device is 126.2 +/- 3.7 W/m. K. Thus, by using the 3-layer laminated structure, thermal conductivity is reduced by around 16% compared to bulk silicon. However, the Seebeck coefficient of the thermoelectric device is degraded compared to that of bulk silicon. It is understood that electrical conductivity is improved by using silicide as a scattering center.

13.
PLoS One ; 6(11): e26675, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22069462

RESUMO

Tuberculosis is still a leading cause of death worldwide. The selection and spread of Mycobacterium tuberculosis multidrug-resistant (MDR-TB) and extensively drug-resistant strains (XDR-TB) is a severe public health problem. Recently, two different classes of chemical series, the benzothiazinones (BTZ) and the dinitrobenzamide (DNB) derivatives have been found to be highly active against M. tuberculosis, including XDR-TB strains. The target of BTZs is DprE1 protein which works in concert with DprE2 to form the heteromeric decaprenylphosphoryl-ß-D-ribose 2'-epimerase, involved in Decaprenyl-Phospho-Arabinose (DPA) biosynthesis. Interestingly, it has been shown that the DNBs block the same pathway thus suggesting that both drugs could share the same target. Moreover, in Mycobacterium smegmatis the overexpression of the NfnB nitroreductase led to the inactivation of the BTZs by reduction of a critical nitro-group to an amino-group. In this work several spontaneous M. smegmatis mutants resistant to DNBs were isolated. Sixteen mutants, showing high levels of DNB resistance, exhibited a mutation in the Cys394 of DprE1. Using fluorescence titration and mass spectrometry it has been possible to monitor the binding between DprE1 and DNBs, achieving direct evidence that MSMEG_6382 is the cellular target of DNBs in mycobacteria. Additionally, M. smegmatis mutants having low levels of resistance to DNBs harbor various mutations in MSMEG_6503 gene encoding the transcriptional repressor of the nitroreductase NfnB. By LC/MS analysis it has been demonstrated that NfnB is responsible for DNB inactivation. Taken together, our data demonstrate that both DNB and BTZ drugs share common resistance mechanisms in M. smegmatis.


Assuntos
Antibacterianos/uso terapêutico , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Mycobacterium smegmatis/efeitos dos fármacos , Racemases e Epimerases/antagonistas & inibidores , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Benzamidas/química , Benzamidas/uso terapêutico , Western Blotting , Domínio Catalítico , Cromatografia Líquida , Dinitrobenzenos/química , Dinitrobenzenos/uso terapêutico , Nitrorredutases/genética , Nitrorredutases/metabolismo , RNA Mensageiro/genética , Racemases e Epimerases/genética , Racemases e Epimerases/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Tiazinas/química , Tiazinas/uso terapêutico
14.
Br J Nutr ; 106(12): 1792-801, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21733337

RESUMO

Non-steroidal anti-inflammatory drugs cause gastric ulceration through a number of mechanisms including inhibition of PG synthesis, generation of reactive oxygen species (ROS) and induction of apoptosis. Recently, matrix metalloproteinases (MMP) have been suggested to play a crucial role in these mechanisms. The present study investigated the protective effect of anthocyanins isolated from black rice bran (Heugjinjubyeo) against naproxen-induced gastric mucosal injury in rats. The oral administration of anthocyanins (5, 25 or 50 mg/kg body weight) showed significant protection against naproxen (80 mg/kg body weight)-induced gastric ulcer and inhibited lipid peroxidation in the gastric mucosa. In addition, pretreatment with anthocyanins resulted in a significant increase in the activities of radical-scavenging enzymes such as superoxide dismutase, catalase and glutathione peroxidase. Also biochemical and zymographic analyses suggested that the administration of anthocyanins gives a significant protection against naproxen-induced gastric antral ulcer through scavenging ROS and regulation of matrix metalloproteinase-2 (MMP-2) activity. The results of intracellular radical activation show that anthocyanins suppress the generation of intracellular ROS and attenuate the suppression of MMP-2 activity by naproxen. These results suggest that anthocyanins extracted from black rice may offer potential remedy of gastric antral ulceration.


Assuntos
Antocianinas/farmacologia , Metaloproteinase 2 da Matriz/metabolismo , Úlcera Gástrica/metabolismo , Úlcera Gástrica/prevenção & controle , Animais , Antocianinas/isolamento & purificação , Anti-Inflamatórios não Esteroides/toxicidade , Antiulcerosos/isolamento & purificação , Antiulcerosos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Feminino , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Expressão Gênica/efeitos dos fármacos , Interleucina-1beta/genética , Peroxidação de Lipídeos/efeitos dos fármacos , Metaloproteinase 9 da Matriz/metabolismo , Naproxeno/toxicidade , Oryza/química , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/genética , Fator de Necrose Tumoral alfa/genética
16.
J Org Chem ; 73(17): 6807-15, 2008 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-18665647

RESUMO

The term "housane" refers to molecules possessing a bicyclo[2.1.0]pentane core. One was designed, synthesized, and used as a precursor of daucene, a member of the carotane class of sesquiterpenes. The total synthesis was completed, thereby marking the first time that housane-derived cation radicals have been used as the key intermediate in the synthesis of a natural product. The transformation used in the construction and featured in the text involves an oxidation to generate the cation radical via either a chemically or an electrochemically mediated electron transfer, the latter process using tris(p-bromophenyl)amine as the mediator. The two methods are compared, and guiding principles are formulated to assist in deciding how best to implement each. Both processes afford an unfavorable equilibrium state that is subsequently drained toward the product by two irreversible events, viz., a 1,2 carbon migration to the site that best stabilizes a positive charge and a second electron transfer, this time being a highly exothermic reduction of the rearranged species to generate the neutral product. A mechanistic proposal calling for the use of a catalytic quantity of the electrochemical mediator and the consumption of exceptionally small quantities of current is advanced. Experimental deviations from these predictions are noted, and a rationale to account for them is presented. Finally, significant differences were noted between the cyclic voltammograms of housanes bearing a CH2OR substituent rather than a methyl group at the bridgehead carbon. Those having the inductively withdrawing group displayed broad and ill-defined curves. The differences were investigated quantum mechanically, and a stereoelectronic argument is formulated stating that broadness of the curve for the ROCH2-substituted systems is the result of a time-averaged sampling of the HOMO energies over the distribution of conformers. The possible generality of the stereoelectronic effect is noted.


Assuntos
Compostos Bicíclicos com Pontes/síntese química , Sesquiterpenos/síntese química , Aminas/química , Catálise , Ciclopentanos/química , Eletroquímica , Transporte de Elétrons , Radicais Livres/química , Imidas/química , Modelos Químicos , Oxirredução , Termodinâmica
17.
J Microbiol Biotechnol ; 18(12): 1990-6, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19131704

RESUMO

Astaxanthin has shown antioxidant, antitumor, and antiinflammatory activities; however, its molecular action and mechanism in the nervous system have yet to be elucidated. We examined the in vitro effects of astaxanthin on the production of nitric oxide (NO), as well as the expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) in lipopolysaccharide (LPS)-stimulated BV2 microglial cells. Astaxanthin inhibited the expression or formation of nitric oxide (NO), iNOS and COX-2 in lipopolysaccharide (LPS)-stimulated BV-2 microglial cells. Astaxanthin also suppressed the protein levels of iNOS and COX-2 in LPS-stimulated BV2 microglial cells. These results suggest that astaxanthin, probably due to its antioxidant activity, inhibits the production of inflammatory mediators by blocking iNOS and COX-2 activation or by the suppression of iNOS and COX-2 degradation.


Assuntos
Ciclo-Oxigenase 2/metabolismo , Lipopolissacarídeos/imunologia , Microglia/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular , Ciclo-Oxigenase 2/genética , Interpretação Estatística de Dados , Expressão Gênica/efeitos dos fármacos , Camundongos , Microglia/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/genética , Xantofilas/farmacologia
18.
J Nanosci Nanotechnol ; 8(10): 4930-3, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19198365

RESUMO

In this paper, we have investigated the phase change memory device with U-shaped bottom electrode using three-dimensional finite element analysis tool. From the simulation, the reset current of PRAM with U-shaped bottom electrode is greatly reduced, compared with the conventional device. And the experimental result clearly shows that the PRAM with U-shaped bottom electrode has 35% smaller RESET current, compared with the conventional PRAM device.

19.
J Microbiol Biotechnol ; 17(5): 847-52, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-18051308

RESUMO

This study investigated an efficient method for the extraction of astaxanthin from the red yeast Xanthophyllomyces dendrorhous. The extraction process comprised three steps: (1) cultivating the yeast; (2) treating the yeast culture suspension with microwaves to destroy the cell walls and microbodies; and (3) drying the yeast and extracting the astaxanthin pigment using ethanol, methanol, acetone, or a mixture of the three as the extraction solvent. Ultimately, various treatment tests were performed to determine the conditions for optimal pigment extraction, and the total carotenoid and astaxanthin contents were quantified. A frequency of 2,450 MHz, an output of 500 watts, and irradiation time of 60 s were the most optimum conditions for yeast cell wall destruction. Furthermore, optimal pigment extraction occurred when using a cell density of 10 g/l at 30 C over 24 h, with a 10% volume of ethanol.


Assuntos
Basidiomycota/química , Basidiomycota/crescimento & desenvolvimento , Basidiomycota/metabolismo , Basidiomycota/efeitos da radiação , Fermentação , Microbiologia Industrial , Micro-Ondas , Solventes , Xantofilas/análise , Xantofilas/isolamento & purificação
20.
J Org Chem ; 72(12): 4351-7, 2007 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-17497802

RESUMO

To utilize housane-derived cation radicals as intermediates for the synthesis of the bicyclo (n.3.0) framework of natural products, a highly regioselective [1,2] shift of carbon to either a radical or an electron-deficient site is required. Herein we describe how this has been accomplished, provide a set of guidelines to assess housane oxidizability prior to its synthesis, and describe a synthesis of housane 18 that capitalizes upon the facility of [1,5] hydrogen shifts in substituted cyclopentadienes. The catalytic electrochemically mediated oxidation of 18 leads to a cation radical that engages in a rearrangement leading to the (4.3.0) adduct 23. The appearance of a catalytic current in the cyclic voltammogram of a solution containing the tris(aryl)amine and housane 18 is an excellent indicator that the amminium cation radical 14*+ is able to oxidize the housane and return the mediator to the original redox couple. DFT calculations show electron density on both the aryl and strained sigma framework in the HOMO of housane 18. From the spin density and electrostatic potential map for the cation radical, a picture where the spin resides on the side that is distal to the substituent emerges, while the hole is proximal to it. Both experiment and theory show that the rearrangement is best characterized as a [1,2] carbon shift toward an electron-deficient site and that migration toward the substituent-bearing carbon is much preferred over the alternative pathway.

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