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1.
J Nanosci Nanotechnol ; 18(3): 1970-1976, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29448694

RESUMEN

The intercalation properties of graphite oxide are important; however, the specific processes and mechanisms associated with intercalation have rarely been elucidated. In this paper, two types of surfactants, polyvinylpyrrolidone and tetradecyltrimethylammonium bromide, were used to thoroughly explore the intercalation properties of graphite oxide. The polyvinylpyrrolidone and tetradecyltrimethylammonium bromide-intercalated graphite oxide composites were synthesized under different conditions and characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray energy dispersive spectroscopy, and transmission electron microscopy. It was found that polyvinylpyrrolidone could be directly intercalated into the graphite oxide layers and tetradecyltrimethylammonium bromide could not effectively react with the waterdispersed graphite oxide. With a low quantity of polyvinylpyrrolidone, only a part of the graphite oxide was intercalated, and the interlayer spacing of the polyvinylpyrrolidone-intercalated composites increased as the polyvinylpyrrolidone: graphite oxide mass ratio increased. When the graphite oxide was dispersed in a 0.05 N NaOH solution, the tetradecyltrimethylammonium bromide rapidly reacted with the graphite oxide, while the mixture of polyvinylpyrrolidone and graphite oxide could not be effectively separated. The intercalated spacing of the tetradecyltrimethylammonium bromideintercalated graphite oxide increased with the tetradecyltrimethylammonium bromide: graphite oxide mass ratio, but its crystalline structure was not as ordered as the polyvinylpyrrolidone-intercalated graphite oxide prepared in the water solution. The infrared spectra of the two surfactant-intercalated graphite oxide samples revealed that the polyvinylpyrrolidone is bonded to the graphite oxide via hydrogen bonding, while the tetradecyltrimethylammonium bromide is bonded via ionic bonding. The mechanism analysis indicated that the polyvinylpyrrolidone could directly enter the graphite oxide layers in the water solution because of the driving force of hydrogen bonding. However, processes such as graphite oxide exfoliation, reactions between the graphite oxide and tetradecyltrimethylammonium bromide, and reaggregation of the graphite oxide sheets are necessary for the formation of tetradecyltrimethylammonium bromide-intercalated graphite oxide.

2.
Biometals ; 28(6): 1063-78, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26525977

RESUMEN

Combined stress of salinity and heavy metal is a serious problem for crop production; however, physiological mechanisms of tolerance to such condition remain elusive in cotton. Here, we used two cotton genotypes differing in salt tolerance, to understand their response to salinity (NaCl) and cadmium (Cd) either alone or in combination (Cd + Na) via hydroponics. Results showed that salinity and/or Cd drastically reduced plant growth, chlorophyll content and photosynthesis, with greater effect observed in Zhongmian 41 (sensitive) than Zhong 9806 (tolerant). Although salinity and/or Cd induced malondialdehyde (MDA) accumulation in Zhongmian 41 at 5 and 10 days after treatment, MDA content remained unchanged in Zhong 9806, implying that Zhongmian 41 but not Zhong 9806 faced oxidative stress following exposure to salinity and/or Cd. Differential responses of antioxidant enzymes such as superoxide dismutase, guaiacol peroxidase, catalase and ascorbate peroxidase to Cd, NaCl and Cd + Na indicate genotype- and time course- dependent variations. In both genotypes, Cd content was decreased while Na concentration was increased under combined stress compared with Cd alone. Importantly, NaCl addition in Cd-containing medium caused remarkable reduction in Cd concentration, with the extent of reduction being also dependent on genotypes. The salt-tolerant genotypes had lower Na concentration than sensitive ones. Furthermore, obvious changes in leaf and root ultrastructure was observed under Cd, Na and Cd + Na stress, however Zhong 9806 was less affected compared with Zhongmian 41. These results may provide novel insight into the physiological mechanisms of Cd + Na stress tolerance in various cotton genotypes.


Asunto(s)
Adaptación Fisiológica/genética , Cadmio/farmacología , Regulación de la Expresión Génica de las Plantas , Genotipo , Gossypium/efectos de los fármacos , Cloruro de Sodio/farmacología , Ascorbato Peroxidasas/genética , Ascorbato Peroxidasas/metabolismo , Catalasa/genética , Catalasa/metabolismo , Clorofila/biosíntesis , Gossypium/genética , Gossypium/metabolismo , Gossypium/ultraestructura , Hidroponía , Malondialdehído/metabolismo , Peroxidasa/genética , Peroxidasa/metabolismo , Fotosíntesis/efectos de los fármacos , Fotosíntesis/genética , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Hojas de la Planta/ultraestructura , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Raíces de Plantas/ultraestructura , Salinidad , Tolerancia a la Sal , Especificidad de la Especie , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo
3.
Indian J Med Res ; 142(4): 430-7, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26609035

RESUMEN

BACKGROUND & OBJECTIVES: Vitamin D insufficiency is prevalent in postmenopausal women and has been related to low bone mineral density (BMD). However, controversial results have been reported for the relationship between serum 25-hydroxyvitamin D [25(OH)D] levels and BMD. This study was done to investigate whether serum 25(OH)D levels were associated with BMD in postmenopausal women living in Guangzhou in southern China. METHODS: This cross-sectional study involved 119 asymptomatic postmenopausal women, aged 48-85 yr, who were consecutively selected from Guangzhou city. BMD was measured at the lumbar spine and femoral neck. The correlation between serum 25(OH)D levels and BMD wes investigated. RESULTS: With increasing serum 25(OH)D levels categorized as <20, 20-30, and ≥ 30ng/ml, the PTH levels decreased gradually ( P=0.031). Bivariate correlation analyses showed an inverse relationship between serum 25(OH)D and PTH levels after controlling for age and BMI (r=-0.209, P=0.023). Although subjects with vitamin D<30 ng/ml had significantly lower BMD, age- and BMI-adjusted serum 25(OH)D was weakly correlated with BMD at femoral neck (r=0.185, P0.045), and not at lumbar spine (r=0.172, p =0 0.063). In multiple regression analyses, serum 25(OH)D was a predictor for BMD at femoral neck (R 2= 0.424). However, serum ß-CTX was a determinant for BMD at lumbar spine (R 2= 0.361). INTERPRETATION & CONCLUSIONS: Serum 25(OH)D levels showed a positive correlation with BMD at femoral neck and serum ß-CTX levels were inversely correlated with BMD at lumbar spine in postmenopausal women. Further studies are needed to elucidate the clinical impact of these findings.


Asunto(s)
Densidad Ósea , Osteoporosis/sangre , Posmenopausia/sangre , Vitamina D/análogos & derivados , Absorciometría de Fotón , Anciano , Anciano de 80 o más Años , China , Colágeno Tipo I/sangre , Femenino , Cuello Femoral/patología , Humanos , Región Lumbosacra/patología , Persona de Mediana Edad , Osteoporosis/patología , Columna Vertebral/metabolismo , Columna Vertebral/patología , Vitamina D/sangre
4.
Front Pediatr ; 12: 1436568, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39175806

RESUMEN

Background: Bronchopulmonary dysplasia (BPD) is the most prevalent chronic lung disease in preterm infants. Studies have shown that Ureaplasma urealyticum (UU) infection is linked to its pathogenesis. However, it remains controversial whether UU colonization in preterm infants increases the risk of developing BPD. Objective: This study aimed to conduct a systematic review and meta-analysis to summarize the correlation between UU and BPD. Methods: We searched PubMed, Embase, the Cochrane Library, Web of Science, Wanfang Database, Chinese National Knowledge Infrastructure Database, Chinese Science and Technique Journal Database, and the China Biology Medicine disc from their inception to March 15, 2024. We included cohort and case-control studies investigating the association between UU infections and BPD in preterm infants, adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The Newcastle-Ottawa Scale was used for quality assessment. The outcome was defined as the continued need for oxygen or respiratory support at 28 days after birth (BPD28) or at 36 weeks postmenstrual age (BPD36). Considering the potential publication bias in observational studies, we used a random-effects meta-analysis model, assessed heterogeneity (I2), performed subgroup analyses, evaluated publication bias, and graded the quality of evidence. Results: The meta-analysis included 36 cohort studies encompassing 5,991 participants. Among these, 20 reported on BPD28, 13 on BPD36, and 3 on both. The results indicated a significant association between UU colonization and BPD28 (odds ratio (OR): 2.26, 95% confidence interval (CI): 1.78-2.85, P < 0.00001, 23 studies, very low certainty of evidence) and BPD36 (OR: 2.13, 95% CI: 1.47-3.07, P < 0.0001, 16 studies, very low certainty of evidence). Conclusion: There is a correlation between UU colonization and the development of BPD in preterm infants. Future research should prioritize well-designed, large-scale, high-quality randomized controlled trials (RCTs) to comprehensively assess the risk of BPD in neonates following UU infection and to provide stronger evidence for clinical screening and prevention strategies to improve the prognosis of affected newborns. Systematic Review Registration: https://www.crd.york.ac.uk/, identifier (CRD42024524846).

5.
BMC Plant Biol ; 13: 35, 2013 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-23452582

RESUMEN

BACKGROUND: Grain protein content (GPC) is an important quality determinant for barley used as malt, feed as well as food. It is controlled by a complex genetic system. GPC differs greatly among barley genotypes and is also variable across different environments. It is imperative to understand the genetic control of barley GPC and identify the genotypes with less variation under the different environments. RESULTS: In this study, 59 cultivated and 99 Tibetan wild barley genotypes were used for a genome-wide association study (GWAS) and a multi-platform candidate gene-based association analysis, in order to identify the molecular markers associated with GPC. Tibetan wild barley had higher GPC than cultivated barley. The significant correlation between GPC and diastatic power (DP), and malt extract confirmed the importance of GPC in determining malt quality. Diversity arrays technology (DArT) markers associated with barley GPC were detected by GWAS. In addition, GWAS revealed two HvNAM genes as the candidate genes controlling GPC. No association was detected between HvNAM1 polymorphism and GPC, while a single nucleotide polymorphism (SNP) (798, P < 0.01), located within the second intron of HvNAM2, was associated with GPC. There was a significant correlation between haplotypes of HvNAM1, HvNAM2 and GPC in barley. CONCLUSIONS: The GWAS and candidate gene based-association study may be effectively used to determine the genetic variation of GPC in barley. The DArT markers and the polymorphism of HvNAM genes identified in this study are useful in developing high quality barley cultivars in the future. HvNAM genes could play a role in controlling barley GPC.


Asunto(s)
Grano Comestible/metabolismo , Estudio de Asociación del Genoma Completo/métodos , Hordeum/genética , Proteínas de Plantas/metabolismo , Grano Comestible/genética , Haplotipos/genética , Desequilibrio de Ligamiento/genética , Proteínas de Plantas/genética , Polimorfismo de Nucleótido Simple/genética
6.
Behav Res Ther ; 171: 104437, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37979217

RESUMEN

BACKGROUND: Attentional bias modification (ABM) has been used to modify the attentional bias (AB) towards smoking-related cues. Still, the effects of ABM are extensively controversial. The present study aimed to investigate the effects of ABM on AB and its two sub-processes named facilitated attention and difficulty in disengagement at two different stimulus durations, as well as test whether the effects of ABM could transfer to new measures of AB. METHOD: Forty-six male college smokers were allocated to either ABM group using a modified visual probe task (n = 24), or the corresponding placebo training (PT) group (n = 22). Participants performed three sessions of training in one week. The pre- and post-training AB and its sub-processes were measured using visual probe task. Cue-target task and pictorial Stroop task were used for testing the transfer effects of ABM. RESULTS: The AB in ABM group was significantly decreased compared with the PT group. Specifically, the facilitated attention was significantly reduced at 200 ms stimulus duration, while the difficulty in disengagement was significantly decreased at 500 ms stimulus duration. The benefit of ABM training could transfer to the cue-target task, but not to the pictorial Stroop task. Meanwhile, no effects of ABM were observed on smoking craving and nicotine dependence. CONCLUSIONS: These findings suggested that the stimulus duration is a crucial factor for the efficacy of ABM on the facilitated attention and the difficulty in disengagement in male college smokers and detected the transfer effects between different measures of AB to some extent. Future studies need to further explore the influence mechanism in distinct stimulus durations.


Asunto(s)
Sesgo Atencional , Humanos , Masculino , Fumadores , Atención , Fumar/terapia , Señales (Psicología)
7.
Adv Mater ; 35(31): e2300577, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37208182

RESUMEN

High-energy electrolytic Zn//MnO2 batteries show potential for grid-scale energy storage, but the severe hydrogen evolution corrosion (HEC) caused by acidic electrolytes results in subdued durability. Here, an all-around protection strategy is reported for achieving stable Zn metal anodes. First, a proton-resistant Pb-containing (Pb and Pb(OH)2 ) interface is constructed on a Zn anode (denoted as Zn@Pb), which in situ forms PbSO4 during H2 SO4 corrosion and protects the Zn substrate from HEC. Second, to improve the plating/stripping reversibility of Zn@Pb, Pb(CH3 COO)2 an additive (denoted as Zn@Pb-Ad) is introduced, which triggers PbSO4 precipitation and releases trace Pb2+ that can dynamically deposit a Pb layer on the Zn plating layer to suppress HEC. The superior HEC resistance stems from the low affinity of PbSO4 and Pb for H+ , as well as strong bonding between Pb-Zn or Pb-Pb, which increase the hydrogen evolution reaction overpotential and the H+ corrosion energy barrier. Consequently, the Zn@Pb-Ad//MnO2 battery runs stably for 630 and 795 h in 0.2 and 0.1 m H2 SO4 electrolytes, respectively, which are >40 times better than that of bare Zn. The as-prepared A h-level battery achieves a one-month calendar life, opening the door to the next generation of high-durable grid-scale Zn batteries.

8.
ChemSusChem ; 15(18): e202201118, 2022 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-35808988

RESUMEN

Zn//MnO2 batteries based on the MnO2 /Mn2+ conversion reaction mechanism featuring high energy density, safety, and affordable cost are promising in large-scale energy storage application. Nonetheless, the continuous H+ intercalation at low potential reduces the average output voltage and the energy efficiency, impeding the development of the high-performance zinc battery. In this work, a strategy was proposed of enhancing the cut-off voltage from the perspective of electrochemical parameters, toward high energy efficiency and stable output voltage of the Zn//MnO2 battery. This strategy was beneficial to promoting MnO2 dissolution/deposition through the increase of acidity caused by the constant accumulation of MnO2 and inhibiting H+ (de)intercalation during cycling process, thereby improving the energy efficiency (83.5 %) along with the stable average output voltage (1.88 V) under the cut-off voltage of 1.8 V. This work provides a new pathway to promote aqueous zinc batteries with high energy density and stable output voltage.

9.
ACS Appl Mater Interfaces ; 13(21): 25410-25420, 2021 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-34009949

RESUMEN

The solid-state lithium-ion battery is proposed as the ultimate form of battery and has rapidly become an updated attentive research field due to its high safety and extreme temperature tolerance. However, current solid-state electrolytes hardly meet the requirement in practical applications due to its low ionic conductivity, weak mechanical properties, and poor interfacial contact between the electrolyte and the electrode. In this work, we developed a double-network-supported poly(ionic liquid)-based ionogel electrolyte (DN-Ionogel) via a one-step method. Due to its compact cross-linking structure, the leakage-free DN-Ionogel electrolyte exhibits outstanding flexibility and favorable mechanical properties. In this ionogel electrolyte, the double network favors dissociation of lithium bis(trifluoromethanesulfony)imide (LiTFSI), further resulting in remarkable ionic conductivity (1.8 × 10-3 S/cm, room temperature), wide electrochemical window (up to 5.0 V), and high lithium-ion transference number (0.33). Furthermore, the cell (LiFePO4||DN-Ionogel||Lithium) delivers a discharge capacity as high as 150.5 mAh/g, stable cyclic performance (over 200 cycles), and superior rate behavior.

10.
J Med Chem ; 64(22): 16711-16730, 2021 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-34748333

RESUMEN

Inhibiting PARP-1/2 offered an important arsenal for cancer treatments via interfering with DNA repair of cancer cells. Novel PARP-1/2 inhibitors were designed by capitalizing on methyl- or ethyl-substituted piperizine ring to capture the characteristics of adenine-ribose binding site (AD site), and their unique binding features were revealed by the cocrystal structures of compounds 4 and 6 in PARP-1. The investigation on structure-activity relationship resulted in compounds 24 and 32 with high enzymatic potency, binding selectivity, and significantly longer residence time for PARP-1 over PARP-2 (compound 24, PARP-1: IC50 = 0.51 nM, PARP-2: IC50 = 23.11 nM; compound 32, PARP-1: IC50 = 1.31 nM, PARP-2: IC50 = 15.63 nM). Furthermore, compound 24 was determined to be an attractive candidate molecule, which possessed an acceptable pharmacokinetic profile and produced remarkable antitumor activity in both breast cancer xenograft model and glioblastoma orthotopic model in mice, either alone or in combination treatment.


Asunto(s)
Antineoplásicos/farmacología , Descubrimiento de Drogas , Piperazinas/química , Poli(ADP-Ribosa) Polimerasa-1/antagonistas & inhibidores , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Quinazolinas/química , Animales , Antineoplásicos/sangre , Antineoplásicos/química , Cristalografía por Rayos X , Perros , Humanos , Ratones , Estructura Molecular , Inhibidores de Poli(ADP-Ribosa) Polimerasas/sangre , Inhibidores de Poli(ADP-Ribosa) Polimerasas/química , Poli(ADP-Ribosa) Polimerasas , Quinazolinas/farmacología , Ratas , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de Xenoinjerto
11.
Blood ; 112(12): 4694-8, 2008 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-18791165

RESUMEN

Large granular lymphocyte (LGL) leukemia is commonly associated with poor hematopoiesis. The first case of pulmonary artery hypertension (PAH) was observed in a 57-year-old woman with natural killer (NK)-LGL leukemia and transfusion-dependent anemia. Using a genetic approach, we demonstrated that killing of pulmonary endothelial cells by patient NK cells was mediated by dysregulated balance in activating and inhibitory NK-receptor signaling. Elevated pulmonary artery pressure and erythroid differentiation improved after disrupting the NK-receptor signaling pathway with 4 courses of a farnesyltransferase inhibitor, tipifarnib. Coincidental association between PAH and LGL leukemia suggest a causal relationship between the expanded lymphocyte population and these clinical manifestations. This trial is registered at www.ClinicalTrials.gov as NCI 6823.


Asunto(s)
Antineoplásicos/uso terapéutico , Farnesiltransferasa/antagonistas & inhibidores , Leucemia Linfocítica Granular Grande/tratamiento farmacológico , Receptores de Células Asesinas Naturales/genética , Células Cultivadas , Inhibidores Enzimáticos/uso terapéutico , Femenino , Humanos , Hipertensión Pulmonar/tratamiento farmacológico , Hipertensión Pulmonar/etiología , Células K562 , Leucemia Linfocítica Granular Grande/complicaciones , Leucemia Linfocítica Granular Grande/genética , Persona de Mediana Edad , Quinolonas/uso terapéutico , Transducción de Señal/genética , Resultado del Tratamiento
12.
ACS Nano ; 14(1): 611-619, 2020 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-31891484

RESUMEN

The rapid development of modern electrical equipment toward miniaturization and high power puts forward stringent requirements to the mechanical reliability, dielectric property, and heat resistance of electrical insulating materials. Simultaneous integration of all these properties for mica-based materials remains unresolved. Herein, inspired by the three-dimensional (3D) chitin nanofiber framework within the layered architecture of natural nacre, we report a large-area layered mica-based nanopaper containing a 3D aramid nanofiber framework, which is prepared by a sol-gel-film transformation process. The coupling of 3D aramid nanofiber framework and oriented mica nanoplatelets imparts the nanopaper with good mechanical strength, particularly outstanding ductility (close to 80%) and toughness (up to 109 MJ m-3), which are 4-240 and 6-220 times higher than those of all other nacre-mimetics. Meanwhile, the excellent mechanical properties are integrated with high dielectric strength (164 kV mm-1), excellent heat resistance (Tg = 268 °C), good solvent resistance, and nonflammability, much better than conventional mica-based materials. Additionally, we successfully demonstrate its continuous production in the form of nanotape. The fabulous multiproperty combination and continuous production capability render the mica-based nanopaper a very promising electrical insulating material in miniaturized high-power electrical equipment.

13.
J Colloid Interface Sci ; 562: 589-597, 2020 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-31771878

RESUMEN

Membrane separation technology is one of the cost effective and most efficient technologies for treatment of wastewater from textile industry. However, development of membranes with better performance and thermal stability is still a highly challenging task. In this study, successful preparation of a novel thermally stable polyimide (PI) polymer was demonstrated using 2,4,6-trimethyl-1,3-phenylenediamine, 4,4'-diaminodiphenylmethane and 1,2,4,5-benzenetetracarboxylic dianhydride components. PI was selected as representative candidate because of its excellent thermal stability (decomposition temperature of 529 °C), as revealed by thermogravimetric analysis. Furthermore, PI polymer was used to fabricate ultrafiltration (UF) membrane by phase inversion process. This UF membrane is especially interesting as it allowed for almost complete penetration of monovalent (NaCl) and divalent (Na2SO4) inorganic salts because of its molecular weight cut off of 9320 Da. Moreover, the membrane exhibited very good surface hydrophilicity with the water contact angle of 67.6°. This PI-based UF membrane was found to be substantially effective as it showed high pure-water and dye-permeation fluxes of 345.10 and 305.58 L m-2 h-1 at 0.1 MPa, respectively. Besides, the membrane exhibited a rejection of 98.65% toward the direct red 23 dye (100 ppm) at 0.1 MPa. Thus, this PI-based UF membrane is highly beneficial and acts as a potential candidate for dye removal from wastewater produced by textile industry.

14.
J Colloid Interface Sci ; 573: 232-240, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32278954

RESUMEN

In this paper, double-layered mesopore-rich hollow carbon microspheres (DHCM) were prepared by a Stöber method using tetraethyl orthosilicate, resorcinol and formaldehyde as precursor materials, and further utilized as carbon sources to prepare the boron and nitrogen co-doped double-layered mesopore-rich hollow carbon microspheres (B, N-DHCM) by hydrothermal approach utilizing ammonium tetraborate tetrahydrate (NH4B5O8·4H2O) as boron and nitrogen sources. Compared with the undoped DHCM, the as-obtained B, N-DHCM displays improved capacitive properties with a high specific capacitance (221.5 F g-1 at 1 A g-1), good rate performance (104.1 F g-1 at 20 A g-1) and superior cycle life (91% of capacitance retention at 3 A g-1 after 10,000 cycles). The outstanding capacitive performances result from the synergistic effect of the unique double-layered mesopore-rich hollow structure contributing to the rate property and cycle stability and the modification of B and N co-doping providing pseudocapacitance for the enhancement of specific capacitance. Therefore, the excellent capacitive behaviors render the B, N-DHCM promising electrode materials for application in supercapacitors and other energy storage systems.

15.
Zhonghua Nei Ke Za Zhi ; 48(4): 277-9, 2009 Apr.
Artículo en Zh | MEDLINE | ID: mdl-19576113

RESUMEN

OBJECTIVE: To investigate the pathogenicity of late-onset Alzheimer disease from the viewpoint of comparative proteomic technology and to screen it from diseases with related protein markers. METHODS: Cerebral cortex tissue of temporal layer of 8 cases of late-onset Alzheimer disease and 5 cases of age-matched autopsied controls with normal brain was chosen for this study. Cerebral proteins were run through immobilized pH gradient (IPG) isoelectric focusing electrophoresis as the first dimension and then vertical SDS-PAGE electrophoresis as the second dimension. Differential proteins were identified with visionworks LS and then analyzed with matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS) and electrospray ionization mass spectrometry (ESI-MS). Finally, the protein was identified by searching in the data bank. RESULTS: Different 2-dimensional gel electrophoresis maps were obtained for the protein spots in the late-onset Alzheimer disease group and the control group gels.11 protein spots showed a significantly differential expression between the two groups of cerebral cortex samples. It was found that the expression of DJ-1 protein was increased in the late-onset Alzheimer disease group in comparison with the control group after searching in the database. CONCLUSION: DJ-1 protein may be a potential marker related to Alzheimer disease pathogenicity. This finding would be helpful to develop new drugs which focus on this protein and prevent neurodegeneration.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Proteínas del Choque Térmico HSP40/metabolismo , Proteómica , Anciano de 80 o más Años , Enfermedad de Alzheimer/patología , Estudios de Casos y Controles , Electroforesis en Gel Bidimensional , Humanos , Masculino , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
16.
ACS Appl Mater Interfaces ; 11(40): 36970-36984, 2019 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-31487152

RESUMEN

Carbon quantum dots (CQDs) as novel types of emerging materials have aroused tremendous attention in recent years. Herein, we report for the first time a new application of 3D CQD-based composite aerogels as excellent electrode materials for alkaline aqueous batteries. The scalable graphitic CQDs are prepared with high yields (>40%) and further utilized to fabricate the novel nitrogen-doped CQDs/reduced graphene oxide/porous Fe2O3 (N-CQDs/rGO/Fe2O3) composite aerogels with different contents of Fe2O3. Benefiting from the unique 3D network composite aerogel structure with a high surface area and hierarchical porous structure as well as the synergistic effect of high-capacity Fe2O3 and highly conductive and stable N-CQDs/rGO, the composite aerogels achieve enhanced electrochemical properties with ultrahigh specific capacity, admirable rate property, and superior cycling performance. Furthermore, the N-CQDs/rGO/Fe2O3-1 electrode (Fe2O3, 34.9 wt %) exhibits the best rate capability (72.1, 58.9, and 46.2% capacity retention at 5, 50, and 100 A g-1, respectively) and cycle performance (80.4% capacity retention at 3 A g-1 over 5000 cycles), while the N-CQDs/rGO/Fe2O3-3 electrode (Fe2O3, 62.3 wt %) displays the highest specific capacity (274.1 mA h g-1 at 1 A g-1). The current research provides a valuable guidance for developing high-performance 3D CQD-based composite aerogels for application in energy storage systems.

17.
Zhongguo Zhong Yao Za Zhi ; 33(23): 2787-9, 2008 Dec.
Artículo en Zh | MEDLINE | ID: mdl-19260312

RESUMEN

OBJECTIVE: To study the chemical constituents of Dregea sinensis var. corrugata. METHOD: The chemical constituents were isolated by various column chromatographic techniques. Structures were elucidated on the basis of NMR data. RESULT: Eight compounds were isolated and their structures were elucidated as syringaresinol (1), syringaresinol-O-3-D-glycopyranoside (2), 3, 4'-dimethoxyl-4, 9, 9'-trihydroxyl-benzofuranneolignan-7'-ene (3), 3, 4'-di- methoxyl-4, 9-dihydroxyl-9'-hydroethyl-benzofuranneolignan-7'-ene (4), conifer-aldehyde (5), sinapic aldehyde (6), 3-hydoxy-1-(4-hydroxy-3-methoxy-phenyl)-propan-1-one (7), 3-hydroxy-1-(3-methoxy-4-hydroxyphenyl)-propan-1-one (8). CONCLUSION: Compounds 1-8 were isolated from Dregea sinensis var. corrugata for the first time.


Asunto(s)
Apocynaceae/química , Plantas Medicinales/química , Propano/análogos & derivados , Propano/química , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Propano/aislamiento & purificación
18.
Environ Sci Pollut Res Int ; 24(10): 9417-9427, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28233214

RESUMEN

Soil salinity is a major abiotic stress that is constraining crop growth and productivity. Greenhouse hydroponic experiments were performed using salt-sensitive (cv. Zhongmian 41) and tolerant (Zhong 9806) cotton seedlings to evaluate how different genotypes responded to salinity stress in the presence of exogenous GSH (reduced glutathione). Cotton plants grown in 150 mM NaCl showed severe reduction in plant height, root length, and shoot and root fresh/dry weight. Salinity also caused reduction in photosynthesis and chlorophyll content, but increase in malondialdehyde (MDA) content. However, the reduction was more in Zhongmian 41 compared to Zhong 9806. Importantly, Sodium concentration was increased in the two genotypes and the induction was more in Zhongmian 41. Calcium and magnesium concentration was decreased in Zhongmian 41; however, in Zhong 9806 there were no significant differences relative to control. Addition of 50 mg L-1 GSH in150 mM NaCl solution (Na + GSH) significantly alleviated salinity stress. Compared with salinity treatment alone (NaCl), Na + GSH increased fresh and dry weight of the root, stem, and leaf, photosynthesis, and chlorophyll content. Obvious ultrastructural alterations were observed in the saline-treated leaf- and root-tip cells. Exogenous GSH greatly ameliorated the salinity-induced damage on the leaf/root ultrastructure, especially in Zhongmian 41.These results advocate a positive role for GSH in alleviation of salinity, which is related to significant improvement in chlorophyll content, photosynthetic performance, and leaf/root ultrastructure.


Asunto(s)
Clorofila/metabolismo , Salinidad , Genotipo , Fotosíntesis/efectos de los fármacos , Hojas de la Planta/metabolismo , Cloruro de Sodio/farmacología
19.
Artículo en Zh | MEDLINE | ID: mdl-16124894

RESUMEN

OBJECTIVE: To study the mechanism of Ca(2+) on the apoptosis induced by hyperthermia in neonate rat hippocampal neurons to provide the applicative evidence of dantrolene for preventing brain injuries. METHODS: Dantrolene, Ca(2+) specific blocking agent, was used in the hyperthermia-induced apoptosis of primary hippocampal neurons in vitro to observe its effect on the apoptosis, fluorescent intensity, and dynamic change of Ca(2+) by flowcytometry and laser confocal microscopy. RESULTS: The rate of apoptosis was decreased significantly after hyperthermia treatment by dantrolene sodium. The intracellular Ca(2+) fluorescent intensity in 42 degrees C treatment group (107.35 +/- 6.0) was significantly lower than that in control group (159.12 +/- 33.8). The concentration of Ca(2+) began to decrease 20 approximately 25 s after adding dantrolene sodium, and reached the lowest level about 50 s later, and then kept lower than the basal level. CONCLUSION: Dantrolene sodium has an important protective effect on hippocampal neurons apoptosis induced by hyperthermia and may have some applicative value of preventing heat-induced brain injury.


Asunto(s)
Apoptosis/efectos de los fármacos , Bloqueadores de los Canales de Calcio/farmacología , Calcio/metabolismo , Dantroleno/farmacología , Hipocampo/citología , Neuronas/metabolismo , Animales , Animales Recién Nacidos , Células Cultivadas , Femenino , Hipocampo/efectos de los fármacos , Masculino , Neuronas/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Temperatura
20.
Anat Rec B New Anat ; 275(1): 190-5, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14628319

RESUMEN

The United States Visible Human Project (VHP) created a digital image data set of complete human male (data acquisition finished in November 1994) and female (data acquisition finished in December 1995) cadavers in magnetic resonance imaging (MRI), computed tomography (CT), and anatomical (anatomic serial section) modes. VHP aroused worldwide enthusiasm for Visible Human Research (VHR), and the data set is being used in a variety of research and educational domains. The Visible Korean Human (VKH) male was produced in March 2001. To accelerate worldwide VHR and to promote virtual anatomy as a revolutionary break with conventional anatomy, more visible human data sets representative of different populations of the world are in demand. The Chinese Visible Human (CVH) male (created in October 2002) and female (created in February 2003) project achieved greater integrity of images, easier blood vessel identification, and were free of organic lesion (unlike the other visible human projects). We performed data acquisition, three-dimensional (3D) reconstruction, and visualization with improved technology to create CVH male and female. CVH is the first volumetric data representing a complete normal adult human male and female of an Asian population. This article presents the history of Chinese Visible Human cadavers and the methods and technology used to produce the data set.


Asunto(s)
Anatomía Transversal/métodos , Educación Médica/métodos , Imagenología Tridimensional , Modelos Anatómicos , Pueblo Asiatico , China , Simulación por Computador , Femenino , Humanos , Masculino
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