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1.
Heliyon ; 10(1): e23354, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38169906

RESUMO

Background: Due to the limitations of current methods for detecting obstructive coronary artery disease (CAD), many individuals are mistakenly or unnecessarily referred for coronary angiography (CAG). Objectives: Our goal is to create a comprehensive database of heart sounds in CAD and develop accurate deep learning algorithms to efficiently detect obstructive CAD based on heart sound signals. This will enable effective screening before undergoing CAG. Methods: We included 320 subjects suspected of CAD who underwent CAG. We employed advanced filtering techniques and state-of-the-art deep learning models (VGG-16, 1D CNN, and ResNet18) to analyze the heart sound signals and identify obstructive CAD (defined as at least one ≥50 % stenosis). To assess the performance of our models, we prospectively recruited an additional 80 subjects for testing. Results: In the test set, VGG-16 exhibited the highest performance with an area under the ROC curve (AUC) of 0.834 (95 % CI, 0.736-0.930), while ResNet-18 and CNN-7 achieved AUCs of only 0.755 (95 % CI, 0.614-0.819) and 0.652 (95 % CI, 0.554-0.770) respectively. VGG-16 demonstrated a sensitivity of 80.4 % and specificity of 86.2 % in the test set. The combined diagnostic model of VGG and DF scores achieved an AUC of 0.915 (95 % CI: 0.855-0.974), and the AUC for VGG combined with PTP scores was 0.908 (95 % CI: 0.845-0.971). The sensitivity and specificity of VGG-16 exceeded 0.85 in patients with coronary artery occlusion and those with 3 vascular lesions. Conclusions: Our deep learning model, based on heart sounds, offers a non-invasive and efficient screening method for obstructive CAD. It is expected to significantly reduce the number of unnecessary referrals for downstream screening.

2.
J Hazard Mater ; 465: 133416, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38183939

RESUMO

The proper treatment of municipal solid waste incineration fly ash (MSWIFA) is a crucial concern due to its hazardous nature and potential environmental harm. To address this issue, this study innovatively utilized dravite and black liquor to solidify MSWIFA. The semi-dry pressing method was employed, resulting in the production of waste alkali-activated cementing material (WACM). This material demonstrated impressive compressive and flexural strength, reaching 45.89 MPa and 6.55 MPa respectively, and effectively solidified heavy metal ions (Pb, Cr, Cu, Cd, and Zn). The leaching concentrations of these ions decreased from 27.15, 10.36, 8.94, 7.00, and 104.4 mg/L to 0.13, 1.05, 0.29, 0.06, and 12.28 mg/L, respectively. The strength of WACM increased by 3 times compared to conventionally produced materials. Furthermore, WACM exhibited excellent long-term performance, with acceptable heavy metal leaching and minimal mechanical degradation. Experimental and theoretical analyses revealed the heavy metal solidification mechanisms, including chemical binding, ion substitution and physical encapsulation. Finally, the on-site application of WACM confirmed its feasibility in meeting both environmental and strength requirements.

3.
Sci Adv ; 9(14): eadg1837, 2023 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-37027471

RESUMO

Thermal management plays a notable role in electronics, especially for the emerging wearable and skin electronics, as the level of integration, multifunction, and miniaturization of such electronics is determined by thermal management. Here, we report a generic thermal management strategy by using an ultrathin, soft, radiative-cooling interface (USRI), which allows cooling down the temperature in skin electronics through both radiative and nonradiative heat transfer, achieving temperature reduction greater than 56°C. The light and intrinsically flexible nature of the USRI enables its use as a conformable sealing layer and hence can be readily integrated with skin electronics. Demonstrations include passive cooling down of Joule heat for flexible circuits, improving working efficiency for epidermal electronics, and stabling performance outputs for skin-interfaced wireless photoplethysmography sensors. These results offer an alternative pathway toward achieving effective thermal management in advanced skin-interfaced electronics for multifunctionally and wirelessly operated health care monitoring.


Assuntos
Dispositivos Eletrônicos Vestíveis , Eletrônica/métodos , Pele , Epiderme , Temperatura Baixa
4.
ACS Nano ; 17(3): 1803-1830, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36727670

RESUMO

Personal thermal management (PTM) is a promising approach for maintaining the thermal comfort zone of the human body while minimizing the energy consumption of indoor buildings. Recent studies have reported the development of numerous advanced textiles that enable PTM systems to regulate body temperature and are comfortable to wear. Herein, recent advancements in thermoregulatory clothing for PTM are discussed. These advances in thermoregulatory clothing have focused on enhancing the control of heat dissipation between the skin and the localized environment. We primarily summarize research on advanced clothing that controls the heat dissipation pathways of the human body, such as radiation- and conductance-controlled clothing. Furthermore, adaptive clothing such as dual-mode textiles, which can regulate the microclimate of the human body, as well as responsive textiles that address both thermal performance (warming and/or cooling) and wearability are discussed. Finally, we include a discussion on significant challenges and perspectives in this field, including large-scale production, smart textiles, bioinspired clothing, and AI-assisted clothing. This comprehensive review aims to further the development of sustainably manufactured advanced clothing with superior thermal performance and outstanding wearability for PTM in practical applications.


Assuntos
Regulação da Temperatura Corporal , Temperatura Corporal , Humanos , Regulação da Temperatura Corporal/fisiologia , Têxteis , Vestuário
5.
J Hazard Mater ; 408: 124404, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33153794

RESUMO

Landfill disposal of municipal solid waste incineration fly ash (MIFA) presents significant environmental and economic burden. This study proposed a novel and high-efficiency approach for stabilisation/solidification (S/S) of MIFA by phosphate-modified calcium aluminate cement (CAC). Experimental results showed that the presence of Pb (the most leachable metal contaminant in the MIFA) retarded the early-stage reaction of CAC, resulting in an extension of setting time and a significant decline of compressive strength of CAC pastes. The incorporation of phosphate additives (10 wt% of binder), especially for trisodium phosphate, in CAC system effectively mitigated the negative impact of Pb on the CAC reaction and reduced the Pb leachability. Elemental mapping results illustrated that Pb2+ coordinated with phosphate to generate insoluble precipitates (e.g., Pb3(PO4)2). The S/S treated MIFA samples fulfilled the compressive strength and leachability requirements for on-site reuse. Overall, this study demonstrated that phosphate-modified CAC is a promising binder for S/S of hazardous MIFA.

6.
Materials (Basel) ; 13(22)2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33213059

RESUMO

This paper aimed to determine the softening laws and fracture toughness of slag-based geopolymer (SG) concrete and mortar (SGC and SGM) as compared to those of Portland cement (PC) concrete and mortar (PCC and PCM). Using three-point bending (TPB) tests, the load vs. mid-span displacement, crack mouth opening displacement, and crack tip opening displacement curves (P-d, P-CMOD, and P-CTOD curves) were all recorded. Bilinear softening laws of the PC and SG series were determined by inverse analysis. Furthermore, the cohesive toughness was predicted using an analytical fracture model. The cohesive toughness obtained by experimental study was consistent with that predicted by analytical method, proving the correctness of the tension softening law obtained from inverse analysis. In addition, both initial and unstable fracture toughness values of SG mortar were lower than those of PC mortar given the same compressive strength. Moreover, the initial fracture toughness of SG concrete was generally lower than that of PC concrete, whereas the unstable fracture toughness exhibited an opposite trend.

7.
Adv Mater ; 32(42): e1906751, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32924184

RESUMO

Subambient daytime radiative cooling (SDRC) provides a promising electricity- and cryogen-free pathway for global energy-efficiency. However, current SDRC systems require stringent surface designs, which are neither cost-effective nor eco-friendly, to selectively emit thermal radiation to outer space and simultaneously maximize solar reflectance. Here, a generic method is developed to upgrade the conventional building-coating materials with a peculiar self-adaptive SDRC effect through combining particle scattering, sunlight-excited fluorescence, and mid-infrared broadband radiation. It is also theoretically proved that heat exchange with the sky can eliminate the use of resonant microstructures and noble metal mirrors in conventional SDRC, and also leads to enhanced daytime cooling yet suppressed nighttime overcooling. When exposed to direct sunlight, the upgraded coating over an aluminum plate can achieve 6 °C (7 °C on a scale-model building) below the ambient temperature under a solar intensity of 744 W m-2 (850 W m-2 ), yielding a cooling power of 84.2 W m-2 . The results pave the way for practical large-scale applications of high-performance SDRC for human thermal comfort in buildings.

8.
Materials (Basel) ; 11(7)2018 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-29996484

RESUMO

The addition of a conductive material into polymer improves its mechanical properties, electrical properties and thermal conductivity and bestows it with good self-sensing and self-adjusting properties. In this study, carbon nanotubes-modified epoxy resins (CNTs-EP) were successfully prepared with good dispersion through the combined methods of three roller rolling, ultrasonic processing and adding surfactant. Tests were conducted to evaluate the resistivity of unloaded modified epoxy resins with different mixing amounts of carbon nanotubes (CNTs), to determine the conductive percolation threshold. On the basis of the test results, a series of monotonic and cyclic uniaxial tensile tests were then conducted to investigate the force sensitivity of the conductivity of epoxy resins modified with different mixing amounts of CNTs. The relationship between the stress and the resistivity under various mixing amounts was studied, indicating that the resistance response could play a good warning role on the damage of the modified polymer material.

9.
Chemosphere ; 190: 90-96, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28985540

RESUMO

Inorganic binder-based stabilization/solidification (S/S) of Pb-contaminated soil is a commonly used remediation approach. This paper investigates the influences of soluble Pb species on the hydration process of two types of inorganic binders: ordinary Portland cement (OPC) and magnesium potassium phosphate cement (MKPC). The environmental leachability, compressive strength, and setting time of the cement products are assessed as the primary performance indicators. The mechanisms of Pb involved in the hydration process are analyzed through X-ray diffraction (XRD), hydration heat evolution, and thermogravimetric analyses. Results show that the presence of Pb imposes adverse impact on the compressive strength (decreased by 30.4%) and the final setting time (prolonged by 334.7%) of OPC, but it exerts much less influence on those of MKPC. The reduced strength and delayed setting are attributed to the retarded hydration reaction rate of OPC during the induction period. These results suggest that the OPC-based S/S of soluble Pb mainly depends on physical encapsulation by calcium-silicate-hydrate (CSH) gels. In contrast, in case of MKPC-based S/S process, chemical stabilization with residual phosphate (pyromorphite and lead phosphate precipitation) and physical fixation of cementitious struvite-K are the major mechanisms. Therefore, MKPC is a more efficient and chemically stable inorganic binder for the Pb S/S process.


Assuntos
Materiais de Construção , Chumbo/química , Compostos de Magnésio/química , Fosfatos/química , Poluentes do Solo/química , Compostos de Cálcio , Géis/química , Minerais/química , Compostos de Potássio/química , Silicatos , Poluentes Químicos da Água/química , Difração de Raios X
10.
Phytother Res ; 31(9): 1341-1348, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28656606

RESUMO

To further explore the underlying antidepressant mechanism of ginseng total saponins (GTS), this study observed the effects on hippocampal astrocyte structural plasticity and hippocampal volume in the corticosterone-induced mouse depression model. Corticosterone (20 mg/kg/day) was administered subcutaneously for 5 weeks, and GTS (12.5, 25, and 50 mg/kg/day; namely GTSL, GTSM, and GTSH) or fluoxetine (10 mg/kg/day) were given intragastrically during the last 3 weeks. On day 33 and day 34, depression-like behavior was observed via a forced swimming test and a tail suspension test, respectively. At 6 h after the last dose of corticosterone (day 35), all mice were sacrificed followed by serum corticosterone assays, stereological analysis of hippocampal glial fibrillary acidic protein-positive (GFAP+ ) astroctyes and hippocampal volume, and hippocampal glycogen tests. Results showed that all doses of GTS ameliorated depression-like behavior and the decrease in hippocampal glycogen without normalizing hypercortisolism. Moreover, GTSH and GTSM reversed the corticosterone-induced reduction in the total number of hippocampal GFAP+ astrocytes and hippocampal volume. Additionally, GTSH alleviated the diminished protrusion length and somal volume of GFAP+ astrocytes induced by corticosterone. These findings imply that the effects of GTS on corticosterone-induced depression-like behavior may be mediated partly through the protection to hippocampal astrocyte structural plasticity. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Antidepressivos/farmacologia , Astrócitos/efeitos dos fármacos , Corticosterona/efeitos adversos , Hipocampo/efeitos dos fármacos , Panax/química , Saponinas/farmacologia , Animais , Atrofia , Corticosterona/sangue , Depressão/induzido quimicamente , Modelos Animais de Doenças , Fluoxetina/farmacologia , Proteína Glial Fibrilar Ácida/metabolismo , Elevação dos Membros Posteriores , Hipocampo/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Natação
11.
Polymers (Basel) ; 9(9)2017 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-30965740

RESUMO

This paper presents finite element (FE) modeling of the debonding behavior of fiber reinforced polymer (FRP)-to-concrete interfaces subject to mixed-mode loading, which is realized through a peeling test of FRP composites externally bonded onto a concrete substrate. A cohesive zone model (CZM) is implemented into the FE model to represent the behavior of the FRP-to-concrete interface. Two element schemes (orthotropic plane stress element and beam element) were employed to simulate the behavior of FRP composite plate in the peeling test. The orthotropic plane stress element scheme, bearing a clear physical background and with an easy definition of the material property parameters following the composite mechanics, is found to be superior to the beam element scheme, and thus is utilized to conduct parametric studies. The influences of the peeling angle, the interfacial parameters (i.e., the configuration of the cohesive zone models, the interfacial damage initiation law (DIL), the interfacial damage evolution law (DEL), the coupling of mode-I and mode-II components), on the mixed-mode failure of the FRP-concrete-interface are carefully investigated. The results showed that the mode I component plays a critical role in the debonding failure of FRP-to-concrete interfaces even when the peeling angle is very small. The failure of FRP-to-concrete interface transits promptly from a mode II-dominated one to a mode I-dominated one when the peeling angle increases to a relatively small value (e.g., 4 degree) and subsequently the peeling force (i.e., the debonding strength of FRP) decreases dramatically. Such mixity of the mode I and mode II components should be appropriately considered for refining the analysis of FRP-strengthened RC beams and the FRP debonding strength design, for which a pure mode II interfacial failure was usually assumed.

12.
Chin Med J (Engl) ; 128(22): 3088-93, 2015 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-26608991

RESUMO

BACKGROUND: Hyperbaric oxygen (HBO) and Ginkgo biloba extract (e.g., EGB 761) were shown to ameliorate cognitive and memory impairment in Alzheimer's disease (AD). However, the exact mechanism remains elusive. The aim of the present study was to investigate the possible mechanisms of HBO and EGB 761 via the function of nuclear factor kappa-B (NF-κB) pathway. METHODS: AD rats were induced by injecting ß-amyloid 25-35 into the hippocampus. All animals were divided into six groups: Normal, sham, AD model, HBO (2 atmosphere absolute; 60 min/d), EGB 761 (20 mg·kg-1·d-1 ), and HBO/EGB 761 groups. Morris water maze tests were used to assess cognitive, and memory capacities of rats; TdT-mediated dUTP Nick-End Labeling staining and Western blotting were used to analyze apoptosis and NF-κB pathway-related proteins in hippocampus tissues. RESULTS: Morris water maze tests revealed that EGB 761 and HBO significantly improved the cognitive and memory ability of AD rats. In addition, the protective effect of combinational therapy (HBO/EGB 761) was superior to either HBO or EGB 761 alone. In line, reduced apoptosis with NF-κB pathway activation was observed in hippocampus neurons treated by HBO and EGB 761. CONCLUSIONS: Our results suggested that HBO and EGB 761 improve cognitive and memory capacity in a rat model of AD. The protective effects are associated with the reduced apoptosis with NF-κB pathway activation in hippocampus neurons.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/terapia , Ginkgo biloba/química , Oxigenoterapia Hiperbárica , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/terapia , NF-kappa B/metabolismo , Extratos Vegetais/uso terapêutico , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/toxicidade , Animais , Modelos Animais de Doenças , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
13.
Chin J Nat Med ; 12(11): 857-68, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25480518

RESUMO

AIM: Variation in structure-related components in plant products prompted the trend to establish methods, using multiple or total analog analysis, for their effective quality control. However, the general use of routine quality control is restricted by the limited availability of reference substances. Using an easily available single marker as a reference standard to determine multiple or total analogs should be a practical option. METHOD: In this study, the Ultra-HPLC method was used for the baseline separation of the main components in ginseng extracts. Using a plant chemical component database, ginsenosides in ginseng extracts were identified by Ultra-HPLC-MS analysis. The charged aerosol detection (CAD) system with post-column compensation of the gradient generates a similar response for identical amounts of different analytes, and thus, the content of each ginsenoside in ginseng extracts was determined by comparing the analyte peak area with the reference standard (determination of total analogs by single marker, DTSM). The total ginsenoside content was determined by the summation of reference standard and other ginsenoside components. RESULTS: The results showed that DTSM approaches were available for the determination of total ginsenosides in a high purity ginseng extract because of the removal of impurities. In contrast, DTSM approaches might be suitable for determination of multiple ginsenosides without interference from impurities in the crude ginseng extract. CONCLUSION: Future practical studies similar to the present study should be conducted to verify that DTSM approaches based on CAD with post-column inverse gradient for uniform response are ideal for the quality control of plant products.


Assuntos
Ginsenosídeos/análise , Panax/química , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/análise , Espectrometria de Massas , Padrões de Referência
14.
Chin J Nat Med ; 12(5): 382-92, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24856763

RESUMO

AIM: To prepare high-purity ginseng total saponins from a water decoction of Chinese ginseng root. METHOD: Total saponins were efficiently purified by dynamic anion-cation exchange following the removal of hydrophilic impurities by macroporous resin D101. For quality control, ultrahigh-performance liquid chromatography with a charged aerosol detector (CAD) was applied to quantify marker components. The total saponin content was estimated by a colorimetric method using a vanillin-vitriol system and CAD response. RESULTS: D201, which consisted of a cross-linked polystyrene matrix and -N(+)(CH3)3 functional groups, was the best of the four anion exchange resins tested. However, no significant difference in cation exchange ability was observed between D001 (strong acid) and D113 (weak acid), although they have different functional groups and matrices. After purification in combination with D101, D201, and D113, the estimated contents of total saponins were 107% and 90% according to the colorimetric method and CAD response, respectively. The total amount of representative ginsenosides Re, Rd, Rg1, and compound K was approximately 22% based on ultrahigh-performance liquid chromatography-CAD quantitative analysis. CONCLUSION: These findings suggest that an ion exchange resin, combined with macroporous adsorption resin separation, is a promising and feasible purification procedure for neutral natural polar components.


Assuntos
Cromatografia por Troca Iônica/métodos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Resinas de Troca Iônica/química , Panax/química , Saponinas/isolamento & purificação , Adsorção , Cromatografia por Troca Iônica/instrumentação , Raízes de Plantas/química , Porosidade , Saponinas/química
15.
Yi Chuan ; 33(6): 576-84, 2011 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-21684862

RESUMO

Chromosomal passenger complex (CPC) is mainly composed of a protein kinase Aurora B, inner centromere protein, Survivin, and Borealin. As in different periods of cell division, CPC can localise correctly to relavent destinations in time and interact on its different substrates in the mitotic cell. CPC modulats phosphorylation of histone H3 in chromatin aggregation and controlls cohesion or segregation of sister chromatids. It is involved in assembly of a mitotic spindle and its chromosomes catched. Moreover, CPC corrects attachment errors between kinetochore and microtuble and gives faithfuly chromosomal segregation and promoting cytokinesis. Here, the structure compenants, localization on chromosomal arms, inner centromere and central spindle, and functions in defferent posisions of CPC were briefly descriped.


Assuntos
Proteínas Cromossômicas não Histona/química , Proteínas Cromossômicas não Histona/metabolismo , Cromossomos/metabolismo , Complexos Multiproteicos/química , Complexos Multiproteicos/metabolismo , Animais , Aurora Quinase B , Aurora Quinases , Cromossomos/genética , Humanos , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/metabolismo , Transporte Proteico
16.
Sheng Li Xue Bao ; 62(6): 489-94, 2010 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-21170493

RESUMO

With the deepening research on pathogenesis of depression, the focus has diverted from the mechanism of regulating monoamines to the basic pathophysiology of depression and the long-term mechanism of antidepressant treatments. cAMP response element binding protein (CREB) in the brain, especially in the hippocampi, as a converging agent of many intracellular signaling transduction pathways is getting increasing attention. To better understand the basic pathophysiology of depression and the long-term mechanism of antidepressant treatments, it is significant to make clear the correlation between hippocampal CREB and antidepressant treatments. This review mainly refers to the formation of CREB and its distribution in hippocampi, the upstream signaling transduction pathways of hippocampal CREB and antidepressant treatments, and the possible antidepressant mechanisms by regulating hippocampal CREB.


Assuntos
Antidepressivos/uso terapêutico , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Depressão/tratamento farmacológico , Depressão/fisiopatologia , Hipocampo/metabolismo , Animais , Hipocampo/efeitos dos fármacos , Humanos , Transdução de Sinais
18.
Mar Biotechnol (NY) ; 11(1): 109-17, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18670810

RESUMO

To produce tachyplesin, an antimicrobial peptide, by a stable and efficient gene engineering approach, cDNAs containing single tachyplesin gene sequence (tac)(1) and tandem repeat of tachyplesin gene sequence (tac2) were respectively developed by annealing two synthesized complementary single-stranded DNAs and constructed into pSBPTQ shuttle vector under the control of the SacB.p.s promoter. The vectors containing the target gene sequence were then transformed into Bacillus subtilis WB800, respectively. Both expression of tac and tac2 were induced by 2% sucrose. The fermentation supernatant was purified by regenerated cellulose membrane tubing (MWCO 2000) and the secreted TAC(2) and TAC2 were about 5 and 10 mg/l of supernatant, respectively. The antimicrobial activities of TAC and TAC2 were measured by the size of bacteriostatic circle of the fermentation supernatants against Escherichia coli K88. Ultrastructural alteration of E. coli K88 and Salmonella typhimurium was observed under scanning electron microscope and transmission electron microscopy. The results showed that in comparison with TAC, TAC2 was expressed at a higher level and also indicating strong antimicrobial activity both in vitro and in vivo.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/farmacologia , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/farmacologia , Peptídeos Cíclicos/genética , Peptídeos Cíclicos/farmacologia , Animais , Peptídeos Catiônicos Antimicrobianos/metabolismo , Sequência de Bases , DNA Bacteriano/genética , Proteínas de Ligação a DNA/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/ultraestrutura , Regulação Bacteriana da Expressão Gênica , Camundongos , Peptídeos Cíclicos/metabolismo , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/ultraestrutura
19.
Yao Xue Xue Bao ; 39(4): 305-8, 2004 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-15303665

RESUMO

AIM: To investigate the effects of fungal elicitors on inophyllums production in suspension cultured cell of Calophyllum inophyllum Linn. METHODS: The pathogen of leaf spot disease of C. inophyllum L. was isolated and prepared as fungal elicitor. The fungal elicitor was added to the medium with different concentrations and culture period. Their effects on biomass and inophyllums content of the suspension of cultured cells were studied. RESULTS: The optimum effects of S-I fungal elicitor concentrations on inophyllums content was 60 mg GE x L(-1). Adding the fungi elicitor into the cell suspension culture system at stationary phase (being cultured for 18 days) resulted in a highest inophyllum content of 59.174 mg x L(-1) at the 3rd day with 27% higher than control. Fungal elicitor treatment promoted the inophyllums accumulation in medium. CONCLUSION: Adding the Stagonospora curtisii (Berk.) Sacc. to the medium was effective approaches to enhance inophyllums yield in the suspension of C. inophyllum L culture cell.


Assuntos
Calophyllum/metabolismo , Cumarínicos/metabolismo , Fungos Mitospóricos/fisiologia , Calophyllum/citologia , Divisão Celular , Células Cultivadas , Meios de Cultura
20.
J Neurochem ; 84(1): 23-34, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12485398

RESUMO

Persistent activation of protein kinase C (PKC) is required for the expression of synaptic plasticity in the brain. There are several mechanisms proposed that can lead to the prolonged activation of PKC. These include long lasting production of lipid activators (diacylglycerol and fatty acid) through mitogen-activated protein (MAP) kinase pathway, and a modification of PKC by reactive oxygen species. In nerve growth factor (NGF)-differentiated PC12 cells, we found that constitutive and autonomous Ca2+-independent PKC activity is associated with 14-3-3 zeta. Because PKC and 14-3-3 zeta are both involved in synaptic plasticity and learning and memory, we examined whether PKC interacts with 14-3-3 zeta in the brain and whether the PKC/14-3-3 zeta complex has autonomous activity. Here we show that three subclasses of PKC, Ca2+-dependent classical PKC, Ca2+-independent novel PKC, and Ca2+-independent and diacylglycerol-insensitive atypical PKC, all interact with 14-3-3 zeta in the rodent brain. The pool size of 14-3-3 zeta bound form of PKC is small (1-4% of each PKC isoform), but they show constitutive and autonomous activity. Our study indicates that the binding of PKC with 14-3-3 zeta is at least in part independent of phosphorylation of PKC and that the C1 domain of PKC is involved in the binding. As both molecules are enriched in synaptic locus, the constitutive PKC activity and its interaction with 14-3-3 zeta could be a mechanism for the persistent PKC activation in the brain.


Assuntos
Encéfalo/metabolismo , Proteína Quinase C/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo , Proteínas 14-3-3 , Animais , Cálcio/fisiologia , Ativação Enzimática , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oligopeptídeos/farmacologia , Proteína Quinase C/química , Estrutura Terciária de Proteína/fisiologia , Ratos , Ratos Sprague-Dawley
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