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1.
Nat Commun ; 14(1): 7153, 2023 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-37935667

RESUMEN

Inaccessibility of stored memory in ensemble cells through the forgetting process causes animals to be unable to respond to natural recalling cues. While accumulating evidence has demonstrated that reactivating memory-stored cells can switch cells from an inaccessible state to an accessible form and lead to recall of previously learned information, the underlying cellular and molecular mechanisms remain elusive. The current study used Drosophila as a model to demonstrate that the memory of one-trial aversive olfactory conditioning, although inaccessible within a few hours after learning, is stored in KCαß and retrievable after mild retraining. One-trial aversive conditioning triggers protein synthesis to form a long-lasting cellular memory trace, approximately 20 days, via creb in KCαß, and a transient cellular memory trace, approximately one day, via orb in MBON-α3. PPL1-α3 negatively regulates forgotten one-trial conditioning memory retrieval. The current study demonstrated that KCαß, PPL1-α3, and MBON-α3 collaboratively regulate the formation of forgotten one-cycle aversive conditioning memory formation and retrieval.


Asunto(s)
Drosophila , Memoria , Animales , Memoria/fisiología , Aprendizaje/fisiología , Condicionamiento Psicológico/fisiología , Recuerdo Mental/fisiología
2.
Cell Rep ; 42(10): 113207, 2023 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-37782557

RESUMEN

Animals rapidly acquire surrounding information to perform the appropriate behavior. Although social learning is more efficient and accessible than self-learning for animals, the detailed regulatory mechanism of social learning remains unknown, mainly because of the complicated information transfer between animals, especially for aversive conditioning information transmission. The current study revealed that, during social learning, the neural circuit in observer flies used to process acquired aversive conditioning information from demonstrator flies differs from the circuit used for self-learned classic aversive conditioning. This aversive information transfer is species dependent. Solitary flies cannot learn this information through social learning, suggesting that this ability is not an innate behavior. Neurons used to process and execute avoidance behavior to escape from electrically shocked flies are all in the same brain region, indicating that the fly brain has a common center for integrating external stimuli with internal states to generate flight behavior.


Asunto(s)
Drosophila melanogaster , Drosophila , Animales , Drosophila melanogaster/fisiología , Condicionamiento Psicológico , Reacción de Prevención , Neuronas
3.
Sci Rep ; 11(1): 20159, 2021 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-34635711

RESUMEN

Paraquat (PQ) is a widely used fast-acting pyridine herbicide. Accidental ingestion or self-administration via various routes can cause severe organ damage. Currently, no effective antidote is available commercially, and the mortality rate of poisoned patients is exceptionally high. Here, the efficacy of anthrahydroquinone-2-6-disulfonate (AH2QDS) was observed in treating PQ poisoning by constructing in vivo and ex vivo models. We then explored the detoxification mechanism of AH2QDS. We demonstrated that, in a rat model, the PQ concentration in the PQ + AH2QDS group significantly decreased compared to the PQ only group. Additionally, AH2QDS protected the mitochondria of rats and A549 cells and decreased oxidative stress damage, thus improving animal survival and cell viability. Finally, the differentially expressed genes were analysed in the PQ + AH2QDS group and the PQ group by NextGen sequencing, and we verified that Nrf2's expression in the PQ + AH2QDS group was significantly higher than that in the PQ group. Our work identified that AH2QDS can detoxify PQ by reducing PQ uptake and protecting mitochondria while enhancing the body's antioxidant activity.


Asunto(s)
Antraquinonas/farmacología , Antídotos/farmacología , Antioxidantes/farmacología , Mitocondrias/efectos de los fármacos , Estrés Oxidativo , Paraquat/envenenamiento , Intoxicación/prevención & control , Células A549 , Animales , Supervivencia Celular , Herbicidas/envenenamiento , Humanos , Masculino , Mitocondrias/patología , Intoxicación/etiología , Intoxicación/patología , Ratas , Ratas Sprague-Dawley
4.
Zhongguo Zhong Yao Za Zhi ; 46(7): 1629-1635, 2021 Apr.
Artículo en Chino | MEDLINE | ID: mdl-33982461

RESUMEN

The chemical properties of characteristic components are significant to the manufacturing quality control of big brand traditional Chinese medicine. In this study, the Huangjing Zanyu Capsules were used as the research carrier to determine the content of five characteristic components including icraiin, emodin, schisandrin A, 2,3,5,4'-tetrahydroxystilbene-2-O-ß-D-glucoside, and osthole simultaneously by high-performance liquid chromatography(HPLC). The results showed that the chemical properties of five cha-racteristic components had a good linear relationship(r>0.999 9) within the quantitative range; the relative standard deviations(RSD) was 0.11%-2.0% and 0.25%-2.8% respectively for intra-day and inter-day precision; the RSD of repeatability was 1.8%-2.6%; the RSD of stability within 48 hours was 0.19%-2.8%, and the average recovery rate was 95.52%-100.1%, all meeting the requirements of pharmaceutical quantitative analysis. Additionally, the interval estimation method was used to directly reflect the distribution of samples with abnormal chemical properties of characteristic components, and the results showed ten samples were detected beyound the 95% control line of confidence level. Multivariate statistical process control(MSPC) method was used to monitor the abnormal samples of Huangjing Zanyu Capsules collectively, and the results showed that two samples were beyond the 95% control line of Hotelling's T~2 and three samples beyond the 95% control line of squared prediction error(SPE), indicating consistent quality control of Huangjing Zanyu Capsules. In conclusion, the proposed method is not only accurate and efficient but also a compensation for the traditional single-component quality control method, providing a scientific basis for the quality control in manufacturing process of Huangjing Zanyu Capsules. Furthermore, it could also serve as a reference method for the quality control in manufacturing big brand traditional Chinese medicine.


Asunto(s)
Medicamentos Herbarios Chinos , Medicina Tradicional China , Cápsulas , Cromatografía Líquida de Alta Presión , Control de Calidad
5.
ACS Appl Mater Interfaces ; 13(4): 4984-4992, 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33492922

RESUMEN

In this work, SnS-SnS2 heterostructured upright nanosheet frameworks are constructed on FTO substrates, which demonstrate promising photocatalytic performances for the conversion of CO2 and water to C2 (acetaldehyde) and C3 (acetone) hydrocarbons without H2 formation. With post annealing in designated atmospheres, the photocatalytic activity of the SnS-SnS2 heterostructured nanosheet framework is critically enhanced by increasing the fraction of crystalline SnS in nanosheets through partial transformation of the SnS2 matrix to SnS but not obviously influenced by improving the crystallinity of the SnS2 matrix. DFT calculations indicate that transformed SnS possesses the CO2 adsorption sites with significantly lower activation energy for the rate-determining step to drive efficient CO2 conversion catalysis. The experimental results and DFT calculations suggest that the SnS-SnS2 heterojunction nanosheet framework photocatalyst experiences Z-scheme charge transfer dynamic to allow the water oxidation and CO2 reduction reactions occurring on the surfaces of SnS2 and SnS, respectively. The Z-scheme SnS-SnS2 heterostructured nanosheet framework photocatalyst exhibits not only efficient charge separation but also highly catalytic active sites to boost the photocatalytic activity for CO2 conversion to C2 and C3 hydrocarbons.

6.
Biotechnol Lett ; 38(7): 1089-96, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27025930

RESUMEN

OBJECTIVE: To evaluate the quantity of Spirulina cultured in seawater, salt-tolerant strains were screened out and their growth and antioxidant accumulation were studied in different salt concentrations RESULTS: Salt tolerance of five Spirulina strains were investigated with modified Zarrouk medium (with 200-800 mM NaCl). All strains grew well with 400 mM NaCl; their growth rates were almost same as in the control medium. Spirulina strains FACHB-843 (SP843) and FACHB-972 (SP972) had the highest salt tolerance their growth rates in 600 mM NaCl were nearly same as the control. Both strains produced more carotene, phycocyanin, polysaccharides, proline and betaine in 400-600 mM NaCl than the control. Salt stress also induced them to produce higher activities of superoxide dismutase and peroxidase. Total antioxidant capacities of SP843 and SP972 peaked at 600 and 400 mM NaCl, respectively. CONCLUSION: Spirulina strains cultured with seawater accumulate more bioactive substances and will have a higher nutritive value.


Asunto(s)
Antioxidantes/metabolismo , Spirulina/metabolismo , Betaína/metabolismo , Peroxidasa/metabolismo , Ficocianina/metabolismo , Prolina/metabolismo , Cloruro de Sodio/farmacología , Spirulina/efectos de los fármacos , Superóxido Dismutasa/metabolismo
7.
Microb Biotechnol ; 6(2): 141-9, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23217085

RESUMEN

With the use of an alkaliphilic bacterium, Corynebacterium humireducens MFC-5, this study investigated the reduction of goethite (α-FeOOH) and degradation of 2,4-dichlorophenoxyacetic acid (2,4-D) mediated by different humic substances (humics) and quinones in alkaline conditions (pH of 9.0). The results indicated that (i) using sucrose as the electron donor, the strain MFC-5 was capable of reducing anthraquinone-2,6-disulfonic acid (AQDS), anthraquinone-2-disulfonic acid (AQS), anthraquinone-2-carboxylic acid (AQC), humic acid (HA) and fulvic acid (FA), and its reducing capability ranked as AQC > AQS > AQDS > FA > HA; (ii) the anaerobic reduction of α-FeOOH and 2,4-D by the strain was insignificant, while the reductions were greatly enhanced by the addition of quinones/humics serving as redox mediators; (iii) the Fe(III) reduction rate was positively related to the content of quinone functional groups and the electron-accepting capacities (EAC) of quinones/humics based on fourier-transform infrared spectroscopy (FT-IR) and electrochemical analyses; however, such a relationship was not found in 2,4-D degradation probably because quinone reduction was not the rate-limiting step of quinone-mediated reduction of 2,4-D. Using the example of α-FeOOH and 2,4-D, this study well demonstrated the important role of humics reduction on the Fe(III)/Fe(II) biogeochemical cycle and chlorinated organic compounds degradation in alkaline reducing environments.


Asunto(s)
Ácido 2,4-Diclorofenoxiacético/metabolismo , Corynebacterium/metabolismo , Compuestos Férricos/metabolismo , Sustancias Húmicas , Biodegradación Ambiental , Biotecnología/métodos , Corynebacterium/clasificación , Concentración de Iones de Hidrógeno , Oxidación-Reducción , Quinonas/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier
8.
J Agric Food Chem ; 60(45): 11238-44, 2012 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-23095105

RESUMEN

A fermentative facultative anaerobe, strain HS01 isolated from subterranean sediment, was identified as Aeromonas hydrophila by 16S rRNA sequence analysis. The biotransformation of 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT), 1,1-dichloro-2,2-bis(4-chlorophenyl) ethylene (DDD), and 1,1-dichloro-2,2-bis (4-chlorophenyl) ethane (DDE) by HS01 was investigated in the presence of goethite and anthraquinone-2,6-disulphonic disodium salt (AQDS). The results demonstrated that HS01 was capable of reducing DDTs, goethite and AQDS. And goethite can significantly enhance the reduction of DDT, DDD and DDE to some extent, while the addition of AQDS can further accelerate the reduction of Fe(III) and DDTs. The products of DDT transformation were identified as a large amount of dominant DDD, and small amounts of 1-chloro-2,2-bis-(p-chlorophenyl)ethane (DDMU), unsym-bis(p-chlorophenyl)-ethylene (DDNU), and 4,4'-dichlorobenzophenone (DBP). The results of cyclic voltammetry suggested that AQDS could increase the amounts of reactive biogenic Fe(II), resulting in the enhanced transformation of DDTs. This investigation gives some new insight in the fate of DDTs related to iron- and humic-reducing bacteria.


Asunto(s)
Aeromonas hydrophila/metabolismo , Antraquinonas/metabolismo , DDT/metabolismo , Sedimentos Geológicos/microbiología , Compuestos de Hierro/metabolismo , Hierro/metabolismo , Minerales/metabolismo , Aeromonas hydrophila/clasificación , Aeromonas hydrophila/genética , Aeromonas hydrophila/aislamiento & purificación , Biodegradación Ambiental , Biotransformación , Sustancias Húmicas/análisis , Oxidación-Reducción
9.
Int J Syst Evol Microbiol ; 61(Pt 4): 882-887, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20495037

RESUMEN

A novel halotolerant, alkaliphilic, humic acid-reducing bacterium, designated MFC-5(T), was isolated from a microbial fuel cell that was fed continuously with artificial wastewater (pH 10.0). Cells were Gram-positive-staining, facultatively anaerobic, non-fermentative, non-motile rods and had a G+C content of 59.0 mol%. Microbial growth was observed with <13 % (w/v) NaCl (optimum 10 %), at pH 7.0-11.0 (optimum pH 9.0) and at 25-45 °C (optimum 37 °C). Strain MFC-5(T) was active in the anaerobic reduction of a humic acid analogue, anthraquinone-2,6-disulphonate, with lactate, formate, acetate, ethanol or sucrose as the electron donor. The major cellular fatty acids were C(18 : 1)ω9c (42.68 %), C(16 : 0) (33.69 %), C(18 : 0) (7.56 %), C(17 : 1)ω8c (5.14 %) and C(17 : 0) (3.39 %). Phylogenetic analysis demonstrated that strain MFC-5(T) displayed >3 % 16S rRNA gene sequence divergence from its closest relatives. Based on phenotypic, genetic and phylogenetic analysis, a novel species, Corynebacterium humireducens sp. nov., is proposed. The type strain is MFC-5(T) ( = NBRC 106098(T)  = CGMCC 2452(T)  = DSM 45392(T)).


Asunto(s)
Fuentes de Energía Bioeléctrica/microbiología , Corynebacterium/clasificación , Corynebacterium/aislamiento & purificación , Anaerobiosis , Antraquinonas/metabolismo , Técnicas de Tipificación Bacteriana , Composición de Base , Análisis por Conglomerados , Corynebacterium/fisiología , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Ácidos Grasos/análisis , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Oxidación-Reducción , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Cloruro de Sodio/metabolismo , Temperatura
10.
Huan Jing Ke Xue ; 31(1): 237-42, 2010 Jan.
Artículo en Chino | MEDLINE | ID: mdl-20329545

RESUMEN

A strain of humic substance- and Fe(III)- reducing bacterium was isolated from the subterranean forest sediment and designated as MFC-3. The strain is facultative anaerobic, Gram-negative, motile and rod (1.0-3.0 microm long, 0.5-1.0 microm wide) and identified as Pantoea agglomerans with the 16S rDNA sequence analyses. Batch experiments were conducted to investigate its humic substance-and Fe(III)-respiring activity. The results showed that MFC-3 was capable of anaerobic respiration on anthraquinone-2,6-disulphonate (AQDS) as the sole terminal electron acceptor with glucose as the electron donor. Within 48 h, MFC-3 could reduce 0.3 mmol x L(-1) AQDS at the expense of 4.5 mmol x L(-1) glucose, and the population of bacteria was increased by 7 times. The strain could use sucrose, glucose, citrate, lactate and formate as electron donors for anaerobic respiration, and the reduction rates of AQDS ranked as sucrose (77%) > glucose (66%) > citrate (50%) > lactate (33%) > glycerol (25%) > formate (17%). MFC-3 can also effectively reduce four types of Fe(III) oxides. After 25 d, the total Fe(II) concentration in the tests of using ferrihydrite, alpha-FeOOH, gamma-FeOOH or alpha-Fe2 O3 as electron acceptor reached 2.5, 2.1, 2.3 and 0.8 mmol x L(-1), respectively. As a strain of environmental origin, MFC-3 is quite useful for the study of extracellular respiration and bioremediation of chlorinated organic pollutants in Fe(III)/humic substance-rich environments.


Asunto(s)
Compuestos Férricos/química , Sustancias Húmicas/análisis , Pantoea/aislamiento & purificación , Pantoea/fisiología , Bacterias Anaerobias/aislamiento & purificación , Bacterias Anaerobias/fisiología , Biodegradación Ambiental , Oxidación-Reducción
11.
FEMS Microbiol Ecol ; 71(1): 106-13, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19895639

RESUMEN

This work studied the ability of Comamonas koreensis CY01 to reduce Fe(III) (hydr)oxides by coupling the oxidation of electron donors and the enhanced biodegradation of 2,4-dichlorophenoxyacetic acid (2,4-D) by the presence of Fe(III) (hydr)oxides. The experimental results suggested that strain CY01 can utilize ferrihydrite, goethite, lepidocrocite or hematite as the terminal electron acceptor and citrate, glycerol, glucose or sucrose as the electron donor. Strain CY01 could transform 2,4-D to 4-chlorophenol through reductive side-chain removal and dechlorination. Under the anaerobic conditions, Fe(III) reduction and 2,4-D biodegradation by strain CY01 occurred simultaneously. The presence of Fe(III) (hydr)oxides would significantly enhance 2,4-D biodegradation, probably due to the fact that the reactive mineral-bound Fe(II) species generated from Fe(III) reduction can abiotically reduce 2,4-D. This is the first report of a strain of C. koreensis capable of reducing Fe(III) (hydr)oxides and 2,4-D, which extends the diversity of iron-reducing bacteria associated with dechlorination.


Asunto(s)
Ácido 2,4-Diclorofenoxiacético/metabolismo , Comamonas/efectos de los fármacos , Comamonas/metabolismo , Compuestos Férricos/farmacología , Ácido 2,4-Diclorofenoxiacético/química , Anaerobiosis , Ácido Cítrico , Comamonas/clasificación , Glucosa , Estructura Molecular , Oxidación-Reducción , Sacarosa , Factores de Tiempo
12.
Zhonghua Zhong Liu Za Zhi ; 27(6): 350-4, 2005 Jun.
Artículo en Chino | MEDLINE | ID: mdl-16117898

RESUMEN

OBJECTIVE: A randomized trial of breast self-examination (BSE) program was carried out to evaluate whether the intensive BSE can reduce the death number of women from breast cancer. METHODS: A total of 266,064 women (age of 30 to 64 years) associated with 519 textile factories in Shanghai had been randomly assigned to a BSE instruction group (132,979 women) or a control group (133,085 women) since 1989. Initial instruction in BSE group included demonstration of proper palpation techniques. It was followed by 2 reinforcement sessions during the subsequent 4 years including video shows, BSE instruction sessions and BSE practice under medical supervision. These activities were continued for 5 years. Attendance at all events was recorded. The cohort was followed through July 2000 for development of breast diseases, and the breast cancer cases were followed up through 2001 for vital status. The data analysis methods used included Kaplan-Meier plots, Log-rank test and Cox modeling. RESULTS: Among women under instruction, 864 breast cancers were detected and 133 breast cancer deaths occurred, and 896 breast cancers were detected and 130 deaths recorded in the control group. The tumor size (P = 0.07), TNM stage (P = 0.39) and cumulative breast cancer mortality rate (P = 0.72) were not significantly different between the 2 groups. However, more and smaller fibroadenomas were detected in the instruction group than in the control group (P < 0.01). CONCLUSION: Intensive instruction in BSE can not reduce mortality rate of breast cancer, but more and smaller benign breast lumps can be detected.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/prevención & control , Autoexamen de Mamas , Adulto , Neoplasias de la Mama/epidemiología , China/epidemiología , Femenino , Humanos , Incidencia , Tamizaje Masivo , Persona de Mediana Edad
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