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1.
Small ; : e2404080, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38923218

RESUMEN

Functional fibers composed of textiles are considered a promising platform for constructing electronic skin (e-skin). However, developing robust electronic fibers with integrated multiple functions remains a formidable task especially when a complex service environment is concerned. In this work, a continuous and controllable strategy is demonstrated to prepare e-skin-oriented ceramic fibers via coaxial wet spinning followed by cold isostatic pressing. The resulting core-shell structured fiber with tightly compacted Al-doped ZnO nanoparticles in the core and highly ordered aramid nanofibers in the shell exhibit excellent tensile strength (316 MPa) with ultra-high elongation (33%). Benefiting from the susceptible contacts between conducting ceramic nanoparticles, the ceramic fiber shows both ultrahigh sensitivity (gauge factor = 2141) as a strain sensor and a broad working range up to 70 °C as a temperature sensor. Furthermore, the tunable core-shell structure of the fiber enables the optimization of impedance matching and attenuation of electromagnetic waves for the corresponding textile, resulting in a minimum reflection loss of -39.1 dB and an effective absorption bandwidth covering the whole X-band. Therefore, the versatile core-shell ceramic fiber-derived textile can serve as a stealth e-skin for monitoring the motion and temperature of robots under harsh conditions.

2.
Sensors (Basel) ; 24(11)2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38894065

RESUMEN

A 9-10-bit adjustable and energy-efficient switching scheme for SAR ADC with one-LSB common-mode voltage variation is proposed. Based on capacitor-splitting technology and common-mode conversion techniques, the proposed switching scheme reduces the DAC switching energy by 96.41% compared to the conventional scheme. The low complexity and the one-LSB common-mode voltage offset of this scheme benefit from the simultaneous switching of the reference voltages of the capacitors corresponding to the positive array and the negative array throughout the entire reference voltage switching process, and the reference voltage of each capacitor in the scheme does not change more than two voltages. The post-layout result shows that the ADC achieves the 54.96 dB SNDR, the 61.73 dB SFDR, and the 0.67 µw power consumption with the 10-bit mode and the 48.33 dB SNDR, the 54.17 dB SFDR, and the 0.47 µw power consumption with the 9-bit mode in a 180 nm process with a 100 kS/s sampling frequency.

3.
Small ; 19(23): e2206091, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36855335

RESUMEN

Bulk nanobubbles fascinate scientists because of their stability over long periods of time and their ability to carry gases, leading to numerous potential applications. Considering the hypoxic tumor microenvironment and the advantages of bulk nanobubbles, lipid-encapsulated oxygen nanobubbles are prepared from free bulk oxygen nanobubbles in this study. The obtained carrier is then modified with a protein fused with the single-chain antibody of human epidermal growth factor receptor 2 (anti-HER2 scFv) and tandem-repeat cytochrome c (anti-HER2 scFv-nCytc) to enhance tumor targeting and induce tumor apoptosis. Copper phthalocyanine is used as the photosensitizer to demonstrate how the oxygen in the nanobubbles affects the efficiency of photodynamic therapy (PDT). The combination of anti-HER2 scFv-nCytc and PDT synergistically improves the therapeutic effect and alleviates hypoxia in tumors in vivo while causing little inflammatory response. Based on the findings, bulk nanobubble water shows promise in the targeted delivery of oxygen and can be combined with antibody therapy to enhance the efficiency of PDT.


Asunto(s)
Neoplasias , Fotoquimioterapia , Humanos , Oxígeno/farmacología , Hipoxia , Apoptosis , Lípidos , Línea Celular Tumoral , Microambiente Tumoral
4.
Photodermatol Photoimmunol Photomed ; 39(6): 620-632, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37641574

RESUMEN

AIM: This study aimed to explore the underlying mechanism of theacrine treatment of UV-induced skin photodamage. MATERIALS AND METHODS: Tandem Mass Tag (TMT) relative quantitative proteomics analysis was used to characterize the proteins and pathways associated with the ability of theacrine to combat photodamage in mouse skin by modeling UV irradiation of the backs of ICR mice. RESULTS: Apoptosis-related proteins and signaling pathways play a key role in the ability of theacrine to protect against skin photodamage, according to proteomic and bioinformatics analysis; molecular docking and Western blotting further revealed that theacrine was associated with apoptosis-related proteins (p53, Bcl-2, Bax, caspase-3, and cleaved-caspase-3) with strong binding affinity, which can significantly reduce skin cell apoptosis induced by UV exposure. CONCLUSION: The findings revealed that theacrine can reduce UVB-induced epidermal damage by controlling the apoptosis signaling pathway, implying that theacrine could be a useful anti-UVB damage agent.


Asunto(s)
Proteínas Reguladoras de la Apoptosis , Proteómica , Ratones , Animales , Caspasa 3 , Simulación del Acoplamiento Molecular , Ratones Endogámicos ICR
5.
J Cell Mol Med ; 25(22): 10638-10649, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34697906

RESUMEN

Cancer treatment has gradually developed from toxic chemotherapy to targeted therapy with fewer side effects. Approximately 30% of breast cancer patients overexpress human epidermal growth factor receptor 2 (HER-2). Previous studies have successfully produced single-chain antibodies (scFv) targeting HER-2+ breast cancer; however, scFv have poor stability, easy aggregation and a shorter half-life, which have no significant effect on targeting therapy. Moreover, scFv has been considered as a drug delivery platform that can kill target cells by effector molecules. However, the functional killing domains of immunotoxins are mainly derived from plant or bacterial toxins, which have a large molecular weight, low tissue permeability and severe side effects. To address these concerns, we designed several apoptotic immune molecules to replace exogenous toxins using endogenous apoptosis-related protein DNA fragmentation factor 40 (DFF40) and tandem-repeat Cytochrome c base on caspase-3 responsive peptide (DEVD). Our results suggest that DFF40 or Cytc fusion scFv specifically targets HER-2 overexpressing breast cancer cells (SK-BR-3 and BT-474) rather than HER-2 negative cells (MDA-MB-231 and MCF-7). Following cellular internalization, apoptosis-related proteins inhibited tumour activity by initiating endogenous apoptosis pathways, which significantly reduced immunogenicity and toxic side effects. Therefore, we suggest that immunoapoptotic molecules may become potential drugs for targeted immunotherapy of breast cancer.


Asunto(s)
Antineoplásicos Inmunológicos/farmacología , Receptor ErbB-2/antagonistas & inhibidores , Proteínas Recombinantes de Fusión/farmacología , Animales , Especificidad de Anticuerpos , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Citocromos c/genética , Modelos Animales de Enfermedad , Femenino , Citometría de Flujo , Orden Génico , Humanos , Ratones , Plásmidos/genética , Receptor ErbB-2/inmunología , Anticuerpos de Cadena Única/genética , Anticuerpos de Cadena Única/inmunología , Ensayos Antitumor por Modelo de Xenoinjerto
6.
FASEB J ; 33(5): 6311-6326, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30768370

RESUMEN

Neuronal polarization depends on the interaction of intracellular chemical and mechanical activities in which the cytoplasmic protein, talin, plays a pivotal role during neurite growth. To better understand the mechanism underlying talin function in neuronal polarization, we overexpressed several truncated forms of talin and found that the presence of the rod domain within the overexpressed talin is required for its positive effect on neurite elongation because the neurite number only increased when the talin head region was overexpressed. The tension in the talin rod was recognized using a Förster resonance energy transfer-based tension probe. Nerve growth factor treatment resulted in inward tension of talin elicited by microfilament force and outward osmotic pressure. By contrast, the glial scar-inhibitor aggrecan weakened these forces, suggesting that interactions between inward pull forces in the talin rod and outward osmotic pressure participate in neuronal polarization. Integrin activation is also involved in up-regulation of talin tension and osmotic pressure. Aggrecan stimuli resulted in up-regulation of docking protein 1 (DOK1), leading to the down-regulation of integrin activity and attenuation of the intracellular mechanical force. Our study suggests interactions between the intracellular inward tension in talin and the outward osmotic pressure as the effective channel for promoting neurite outgrowth, which can be up-regulated by integrin activation and down-regulated by DOK1.-Wang, Y., Zhang, X., Tian, J., Shan, J., Hu, Y., Zhai, Y., Guo, J. Talin promotes integrin activation accompanied by generation of tension in talin and an increase in osmotic pressure in neurite outgrowth.


Asunto(s)
Integrinas/metabolismo , Mecanotransducción Celular , Proyección Neuronal , Presión Osmótica , Talina/metabolismo , Citoesqueleto de Actina/química , Citoesqueleto de Actina/metabolismo , Agrecanos/farmacología , Animales , Línea Celular Tumoral , Células Cultivadas , Proteínas de Unión al ADN/metabolismo , Humanos , Ratones , Ratones Endogámicos C57BL , Factores de Crecimiento Nervioso/farmacología , Neuronas/citología , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Células PC12 , Proteínas de Unión al ARN/metabolismo , Ratas , Talina/química
7.
J Environ Manage ; 266: 110424, 2020 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-32392133

RESUMEN

Understanding how complex urban factors affect the Urban Heat Island (UHI) is crucial for assessing the impacts of urban planning and environmental management on the thermal environment. This paper investigates the relationships between two-dimensional (2D) and three-dimensional (3D) factors and land surface temperatures (LST) within the Olympic Area of Beijing in different seasons, using the boosted regression tree (BRT) model. The BRT model captures the specific contributions of each urban factor to LST in each season and across a continuum of magnitudes for this factor. The results show that these relationships are complex and highly nonlinear. The four most common dominant factors are the Normalized Difference Built-up Index (NDBI), the Normalized Difference Vegetation Index (NDVI), a gravity index for parks (GPI), and average building height (BH). The most important factor in spring is NDBI, with a 45.5% contribution rate. In the other seasons, NDVI is the dominant factor, with contributions of 40% in summer, 21% in autumn, and 19% in winter. NDVI has an overall negative impact on LST in spring and summer, with a quadratic nonlinear decreasing curve, but a positive one in autumn and winter. The 2D land-use variables are most strongly related to LST in summer and spring, but 3D building-related variables have stronger impacts in colder weather. The Sky View Factor (SVF), a 3D measure of urban morphology, has also strong impacts in summer and winter. Both a building-based and a DSM-based SVFs are computed. The latter accounts for buildings, bridges, and trees. In contrast to a building-based SVF, the DSM-based SVF reduces LST when it varies between 0 and 0.75, reflecting the effects of high-density tree canopies that increase shades and evapotranspiration while blocking sky view. The marginal effect curves produced by the BRT are often characterized by thresholds. For instance, the maximal NDVI effect in summer takes place when NDVI = 0.7, suggesting that a very intense green coverage is not necessary to achieve maximal thermal results. Implications for urban planning and environmental management are outlined, including the increased use of evergreen trees that provide thermal benefits in both summer and winter.


Asunto(s)
Monitoreo del Ambiente , Calor , Beijing , Ciudades , Islas , Estaciones del Año
8.
Cell Mol Neurobiol ; 39(2): 241-254, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30554401

RESUMEN

Retinoic acid-induced 14 is a developmentally regulated gene induced by retinoic acid and is closely associated with NIK/NF-κB signaling. In the present study, we examined the effect of RAI14 on mTOR-mediated glial inflammation in response to inflammatory factors and chemical ischemia. A U87 cell model of LPS- and TNF-α-induced inflammation was used to investigate the role of RAI14 in glial inflammation. U87 cells were treated with siR-RAI14 or everolimus to detect the correlation between mTOR, RAI14, and NF-κB. CoCl2-stimulated U87 cells were used to analyze the effect of RAI14 on mTOR-mediated NF-κB inflammatory signaling under chemical hypoxia. LPS and TNF-α stimulation resulted in the upregulation of RAI14 mRNA and protein levels in a dose- and time-dependent manner. RAI14 knockdown significantly attenuated the level of pro-inflammatory cytokine via inhibiting the IKK/NF-κB pathway. Treatment with an mTOR inhibitor (everolimus) ameliorated NF-κB activity and IKKα/ß phosphorylation via RAI14 signaling. Notably, RAI14 also enhanced mTOR-mediated NF-κB activation under conditions of chemical hypoxia. These findings provide significant insight into the role of RAI14 in mTOR-induced glial inflammation, which is closely associated with infection and ischemia stimuli. Thus, RAI14 may be a potential drug target for the treatment of inflammatory diseases.


Asunto(s)
Proteínas del Citoesqueleto/metabolismo , Glioblastoma/metabolismo , Glioblastoma/patología , Inflamación/metabolismo , Inflamación/patología , Estrés Fisiológico , Serina-Treonina Quinasas TOR/metabolismo , Factores de Transcripción/metabolismo , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Astrocitos/patología , Hipoxia de la Célula/efectos de los fármacos , Línea Celular Tumoral , Citocinas/genética , Citocinas/metabolismo , Proteínas del Citoesqueleto/genética , Everolimus/farmacología , Técnicas de Silenciamiento del Gen , Glioblastoma/genética , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Quinasa I-kappa B/metabolismo , Mediadores de Inflamación/metabolismo , Modelos Biológicos , FN-kappa B/metabolismo , Fosforilación/efectos de los fármacos , Biosíntesis de Proteínas/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Estrés Fisiológico/efectos de los fármacos , Factores de Transcripción/genética , Transcripción Genética/efectos de los fármacos
9.
J Nat Prod ; 82(2): 318-323, 2019 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-30747534

RESUMEN

Armeniaspirols (1-3) are potent antibiotics against Gram-positive pathogens. Through a biosynthetic investigation, we identified four enzymes involved in the structural modification of 1-3. Manipulation of their activity led to the generation of 4-6 and nine novel analogues, 7-15. Bioactivity assessments revealed that the pyrrole chloro group and the methyl group are important for the antimicrobial activities of armeniaspirols, which lays the foundation for future structure optimization and mechanism of action studies of armeniaspirols.


Asunto(s)
Antibacterianos/biosíntesis , Familia de Multigenes , Pirroles/metabolismo , Compuestos de Espiro/metabolismo , Streptomyces/genética , Pirroles/farmacología , Compuestos de Espiro/farmacología
10.
Photodermatol Photoimmunol Photomed ; 35(5): 360-368, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31166622

RESUMEN

BACKGROUND/PURPOSE: Ultraviolet (UV) A (315-400 nm) is the UV light that most frequently reaches the Earth's surface and can penetrate the epidermis through to the dermis, causing various issues, including skin aging and skin cancer. The results of our previous studies have shown that the flavonoid monomer cyanidin-3-o-glucoside (C3G) can effectively inhibit primary human dermal fibroblast (HDF) oxidative damage and apoptosis caused by UVA radiation. Many flavonoids can regulate the level of autophagy. However, whether C3G inhibits UVA-induced oxidative damage to primary HDFs by regulating autophagy levels remains unclear. METHODS AND RESULTS: In this study, we used different doses (0-12 J/cm2 ) of UVA to irradiate cells and showed that the expression levels of autophagy-related gene 5 (Atg5) and microtubule-associated protein 1 light chain 3 (LC3)-II in primary HDFs first increased and then decreased. The expression of Atg5 and LC3-II was significantly decreased under 12 J/cm2 (light-damage model). C3G increased the levels of Atg5 and LC3-II. Primary HDFs were pretreated with C3G, followed by treatment with the autophagy inhibitor 3-methyladenine (3-MA) after 12 J/cm2 UVA irradiation. The inhibitory effects of C3G on morphological changes, oxidative damage, and apoptosis in primary HDFs induced by UVA were significantly decreased. CONCLUSION: C3G can inhibit UVA-induced damage to primary HDFs by inducing autophagy. These results provide a theoretical basis for the application of natural compounds to resist light damage to the skin in the future.


Asunto(s)
Antocianinas/farmacología , Autofagia , Dermis/metabolismo , Fibroblastos/metabolismo , Glucósidos/farmacología , Rayos Ultravioleta/efectos adversos , Regulación hacia Arriba , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Autofagia/efectos de los fármacos , Autofagia/efectos de la radiación , Células Cultivadas , Dermis/patología , Fibroblastos/patología , Humanos , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/efectos de la radiación
11.
Sensors (Basel) ; 19(10)2019 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-31117279

RESUMEN

In the existing stochastic gradient matching pursuit algorithm, the preliminary atomic set includes atoms that do not fully match the original signal. This weakens the reconstruction capability and increases the computational complexity. To solve these two problems, a new method is proposed. Firstly, a weak selection threshold method is proposed to select the atoms that best match the original signal. If the absolute gradient coefficients were greater than the product of the maximum absolute gradient coefficient and the threshold that was set according to the experiments, then we selected the atoms that corresponded to the absolute gradient coefficients as the preliminary atoms. Secondly, if the scale of the current candidate atomic set was equal to the previous support atomic set, then the loop was exited; otherwise, the loop was continued. Finally, before the transition estimation of the original signal was calculated, we determined whether the number of columns of the candidate atomic set was smaller than the number of rows of the measurement matrix. If this condition was satisfied, then the current candidate atomic set could be regarded as the support atomic set and the loop was continued; otherwise, the loop was exited. The simulation results showed that the proposed method has better reconstruction performance than the stochastic gradient algorithms when the original signals were a one-dimensional sparse signal, a two-dimensional image signal, and a low-rank matrix signal.

12.
Bioorg Med Chem ; 26(8): 1488-1494, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29452840

RESUMEN

Borrelidin A (1) is produced by several species of Streptomyces and within its bioactive scaffold, the vinylic nitrile moiety is essential for activity. We report herein newly discovered members of the borrelidin family, borrelidin F (2), borrelidin G (3), borrelidin H (4) and borrelidin I (5); all were isolated from Streptomyces rochei SCSIO ZJ89 originating from a mangrove-derived sediment sample. These structurally diverse metabolites enabled a number of new structure-activity relationships (SARs) to be identified, especially with respect to the different configurations at the C11-OH and C12-C15 double bonds for which the absolute configurations were determined using spectroscopic methods. Importantly, borrelidin H (4) was found to have a therapeutic window superior to that of borrelidin A (1) in vitro and could inhibit migration of cancer cells.


Asunto(s)
Antineoplásicos/farmacología , Streptomyces/química , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Línea Celular , Movimiento Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Alcoholes Grasos/química , Alcoholes Grasos/aislamiento & purificación , Alcoholes Grasos/farmacología , Humanos , Estructura Molecular , Relación Estructura-Actividad , Cicatrización de Heridas/efectos de los fármacos
13.
Macromol Rapid Commun ; 39(14): e1800102, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29786920

RESUMEN

The formulation of optoelectronic components into 1D nanostructures allows the promotion of new materials with multifunctionalities. In this work, it is demonstrated that new synthesis of photocatalytic carbon nanofiber decorated with semi-embedded titanium oxide (TiO2 ), namely, TiO2 @carbon fiber, is conveniently accessed through the electrospinning of polyacrylonitrile polymer and TiO2 particle comixture, and then followed by photon-activated self-erosion to expose the embedded TiO2 and carbonization. The hybrid nanofibers are characterized by field emission scanning electron microscopy, transmission electron microscopy, and X-ray diffraction analysis. Furthermore, the photocatalytic activities of the resultant fibers are tested with photodegradation of Rhodamine B in aqueous solution, which reveals that the carbon nanofiber with semi-embedded TiO2 drastically improved catalytic efficiency and recyclability, comparing to those fibers without or with embedded TiO2 .


Asunto(s)
Catálisis , Fotólisis , Rodaminas/química , Titanio/química , Resinas Acrílicas/química , Adsorción , Carbono/química , Fibra de Carbono , Nanofibras/química
14.
Chirality ; 2018 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-29885046

RESUMEN

We previously identified and characterized 1 novel deep-sea microbial esterase PHE21 and used PHE21 as a green biocatalyst to generate chiral ethyl (S)-3-hydroxybutyrate, 1 key chiral chemical, with high enantiomeric excess and yield through kinetic resolution. Herein, we further explored the potential of esterase PHE21 in the enantioselective preparation of secondary butanol, which was hard to be resolved by lipases/esterases. Despite the fact that chiral secondary butanols and their ester derivatives were hard to prepare, esterase PHE21 was used as a green biocatalyst in the generation of (S)-sec-butyl acetate through hydrolytic reactions and the enantiomeric excess, and the conversion of (S)-sec-butyl acetate reached 98% and 52%, respectively, after process optimization. Esterase PHE21 was also used to generate (R)-sec-butyl acetate through asymmetric transesterification reactions, and the enantiomeric excess and conversion of (R)-sec-butyl acetate reached 64% and 43%, respectively, after process optimization. Deep-sea microbial esterase PHE21 was characterized to be a useful biocatalyst in the kinetic resolution of secondary butanol and other valuable chiral secondary alcohols.

15.
Chirality ; 30(6): 769-776, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29573466

RESUMEN

The two enantiomers of ethyl 3-hydroxybutyrate are important intermediates for the synthesis of a great variety of valuable chiral drugs. The preparation of chiral drug intermediates through kinetic resolution reactions catalyzed by esterases/lipases has been demonstrated to be an efficient and environmentally friendly method. We previously functionally characterized microbial esterase PHE21 and used PHE21 as a biocatalyst to generate optically pure ethyl (S)-3-hydroxybutyrate. Herein, we also functionally characterized one novel salt-tolerant microbial esterase WDEst17 from the genome of Dactylosporangium aurantiacum subsp. Hamdenensis NRRL 18085. Esterase WDEst17 was further developed as an efficient biocatalyst to generate (R)-3-hydroxybutyrate, an important chiral drug intermediate, with the enantiomeric excess being 99% and the conversion rate being 65.05%, respectively, after process optimization. Notably, the enantio-selectivity of esterase WDEst17 was opposite than that of esterase PHE21. The identification of esterases WDEst17 and PHE21 through genome mining of microorganisms provides useful biocatalysts for the preparation of valuable chiral drug intermediates.


Asunto(s)
Ácido 3-Hidroxibutírico/química , Esterasas/química , Esterasas/metabolismo , Actinobacteria/enzimología , Actinobacteria/genética , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/aislamiento & purificación , Proteínas Bacterianas/metabolismo , Catálisis , Esterasas/genética , Esterasas/aislamiento & purificación , Concentración de Iones de Hidrógeno , Peso Molecular , Sales (Química)/química , Cloruro de Sodio/química , Solventes/química , Estereoisomerismo , Especificidad por Sustrato , Tensoactivos/química , Temperatura
16.
Photodermatol Photoimmunol Photomed ; 34(4): 224-231, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29235191

RESUMEN

BACKGROUND/PURPOSE: Ultraviolet-A (UVA) radiation can induce photoaging and skin cancer, but means to prevent or treat UVA-induced skin damage require further study. We investigated the effects of cyanidin-3-o-glucoside (C3G), a monomer of anthocyanin, on UVA-induced damage in primary human dermal fibroblasts (HDFs), and we identify possible mechanisms underlying the protective effects of this compound. METHODS: Primary HDFs were pretreated with 80 µmol/L C3G for 2 hours and UVA irradiated at 12 J/cm2 . The cells were then incubated with 80 µmol/L C3G for 12 hours after irradiation. HDFs were randomly divided into control, UVA treatment, C3G, and UVA treatment plus C3G pretreatment groups. RESULTS: C3G increased the cell viability of primary HDFs and decreased UVA-induced ROS production and apoptosis rate. Compared to the UVA group, the UVA plus pretreatment with C3G group displayed increased Bcl-2 expression and Bcl-2/Bax ratio, decreased cleaved caspase-3 and p-P38 levels, and increased ERK phosphorylation; no significant effect on p-JNK levels was observed. CONCLUSION: C3G reduced UVA-induced HDF oxidative damage and apoptosis, likely be related to the down-regulation of p-P38, up-regulation of ERK protein phosphorylation.


Asunto(s)
Antocianinas/farmacología , Apoptosis , Dermis/metabolismo , Fibroblastos/metabolismo , Glucósidos/farmacología , Rayos Ultravioleta/efectos adversos , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Caspasa 3/metabolismo , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Células Cultivadas , Dermis/patología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Fibroblastos/patología , Humanos , Fosforilación/efectos de los fármacos , Fosforilación/efectos de la radiación , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Proteína X Asociada a bcl-2/metabolismo
17.
Mar Drugs ; 16(6)2018 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-29843358

RESUMEN

Nine new angucycline glycosides designated urdamycins N1⁻N9 (1⁻9), together with two known congener urdamycins A (10) and B (11), were obtained from a mangrove-derived Streptomycesdiastaticus subsp. SCSIO GJ056. The structures of new compounds were elucidated on the basis of extensive spectroscopic data analysis. The absolute configurations of 6⁻9 were assigned by electronic circular dichroism calculation method. Urdamycins N6 (6) and N9 (9) represent the first naturally occurring (5R, 6R)-angucycline glycosides, which are diastereomers of urdamycins N7 (7) and N8 (8), respectively.


Asunto(s)
Aminoglicósidos/química , Antraquinonas/química , Antibacterianos/química , Organismos Acuáticos/metabolismo , Streptomyces/metabolismo , Aminoglicósidos/aislamiento & purificación , Antraquinonas/aislamiento & purificación , Antibacterianos/aislamiento & purificación , Dicroismo Circular , Espectroscopía de Resonancia Magnética , Estructura Molecular , Humedales
18.
World J Microbiol Biotechnol ; 34(9): 124, 2018 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-30083971

RESUMEN

One novel protease sin3406-1 was identified from Streptomyces niveus SCSIO 3406, which was isolated from the deep sea of the South China Sea, and heterologously expressed in E. coli BL21(DE3). Protease sin3406-1 was further used as a green biocatalyst in the kinetic resolution of racemic ethyl-3-hydroxybutyrate. After careful process optimization, chiral product ethyl (S)-3-hydroxybutyrate was generated with an enantiomeric excess of over 99% and a conversion rate of up to 50% through direct hydrolysis of inexpensive racemic ethyl-3-hydroxybutyrate catalyzed by sin3406-1. Interestingly, protease sin3406-1 exhibited the same enantio-preference as that of esterase PHE21 during the asymmetric hydrolysis of the ester bonds of racemic ethyl-3-hydroxybutyrate. Through mutation studies and molecular docking, we also demonstrated that the four residues close to the catalytic center, S85, A86, Q87 and Y254, played key roles in both the hydrolytic activity and the enantioselectivity of protease sin3406-1, possibly through forming hydrogen bonds between the enzyme and the substrates. Deep-sea microbial proteases represented by sin3406-1 are new contributions to the biocatalyst library for the preparation of valuable chiral drug intermediates and chemicals through enzymatic kinetic resolution.


Asunto(s)
Endopeptidasas/genética , Endopeptidasas/metabolismo , Hidroxibutiratos/metabolismo , Agua de Mar/microbiología , Streptomyces/enzimología , Composición de Base , Secuencia de Bases , Catálisis , China , Clonación Molecular , Endopeptidasas/química , Endopeptidasas/efectos de los fármacos , Estabilidad de Enzimas , Escherichia coli/genética , Concentración de Iones de Hidrógeno , Hidrólisis , Cinética , Metales/farmacología , Simulación del Acoplamiento Molecular , Mutación , Análisis de Secuencia de Proteína , Solventes/farmacología , Estereoisomerismo , Streptomyces/genética , Especificidad por Sustrato , Tensoactivos/farmacología , Temperatura
19.
Pediatr Int ; 58(9): 902-5, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27389718

RESUMEN

Idiopathic eruptive macular pigmentation (IEMP) is a rare dermatological disorder with generally unclear etiology and pathogenesis. A 5½-year-old girl was referred to hospital with a 10 month history of brown skin rashes. In early infancy, citrin deficiency had been diagnosed with the SLC25A13 genotype c.851_854del4/c.998G > A, but all clinical and laboratory abnormalities recovered following the introduction of a lactose-free and medium-chain triglyceride-enriched formula. Physical examination at referral indicated symmetric, multiple and non-scaly brown macules on the neck, trunk, buttocks and proximal parts of the extremities. Histopathology indicated epidermal basal layer hyperpigmentation with an irregular distribution, along with a large number of melanophages in the upper dermis. The diagnosis of IEMP was thus made. Within 2 years of follow up, the rashes disappeared spontaneously and gradually. To our knowledge, this is the first description of IEMP in a patient with silent citrin deficiency.


Asunto(s)
Proteínas de Unión al Calcio/deficiencia , Citrulinemia/complicaciones , Dermatosis Facial/diagnóstico , Hiperpigmentación/diagnóstico , Transportadores de Anión Orgánico/deficiencia , Proteínas de Unión al Calcio/sangre , Preescolar , Citrulinemia/sangre , Diagnóstico Diferencial , Dermatosis Facial/sangre , Dermatosis Facial/etiología , Femenino , Humanos , Hiperpigmentación/sangre , Hiperpigmentación/etiología , Transportadores de Anión Orgánico/sangre , Remisión Espontánea
20.
Cell Tissue Bank ; 17(1): 147-59, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26070350

RESUMEN

There are controversial reports about cardiac differentiation potential of mesenchymal stem cells (MSCs), and there is still no well-defined protocol for the induction of cardiac differentiation. The effects of retinoic acid (RA) and dimethyl sulfoxide (DMSO) on the proliferation and differentiation of human fetal liver-derived MSCs (HFMSCs) as well as the pluripotent state induced by 5-azacytidine (5-aza) in vitro were investigated. MSCs were isolated from fetal livers and cultured in accordance with previous reports. Cells were plated and were treated for 24 h by the combination of 5-aza, RA and DMSO in different doses. Different culture conditions were tested in our study, including temperature, oxygen content and medium. Three weeks later, cells were harvested for the certification of cardiac differentiation as well as the pluripotency, which indicated by cardiac markers and Oct4. It was found that the cardiac differentiation was only induced when HFMSCs were treated in the following conditions: in high-dose combination (5-aza 50 µM + RA 10(-1) µM + DMSO 1 %) in cardiac differentiation medium at 37 °C and 20 % O2. The results of immunohistochemistry and quantitative RT-PCR showed that about 40 % of the cells positively expressed Nkx2.5, desmin and cardiac troponin I, as well as Oct4. No beating cells were observed during the period. The combined treatment with RA, DMSO and 5-aza in high-dose could promote HFMSCs to differentiate into cardiomyocyte-like cells and possibly through the change of their pluripotent state.


Asunto(s)
Azacitidina/farmacología , Diferenciación Celular/efectos de los fármacos , Dimetilsulfóxido/farmacología , Feto/citología , Hígado/embriología , Células Madre Mesenquimatosas/citología , Tretinoina/farmacología , Biomarcadores/metabolismo , Forma de la Célula/efectos de los fármacos , Humanos , Inmunohistoquímica , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Miocardio/citología , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Osteogénesis/efectos de los fármacos , Fenotipo , Reacción en Cadena en Tiempo Real de la Polimerasa , Reproducibilidad de los Resultados
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