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1.
Opt Lett ; 47(18): 4608-4611, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36107044

RESUMEN

The magneto-optical resonance response of sodium atoms generated by a high-energy solid-state pulse Nd:YAG laser is studied in different external magnetic fields. We investigate the resonance fluorescence signal of sodium atoms in a simulated sea fog environment based on the laser-induced plasma (LIP) effect. By ionizing an NaCl solution spray to generate sodium atoms in an atmospheric environment, we build a Bell-Bloom magneto-optical resonance system under laboratory conditions. With the help of laser-induced breakdown spectroscopy (LIBS) and extinction spectrum, we obtain sodium atoms with a lifetime of 250 µs. A narrowband tunable continuous wave (CW) 589-nm laser tuned at the D2 line with a modulation frequency around the Larmor frequency is used as the pump beam to polarize sodium atoms in the test magnetic field. We find that the magneto-optical resonance signals vary with different external magnetic fields and the positions of the resonance signal are consistent with the theoretical values. An intrinsic magnetometric sensitivity of 620.4 pT in a 1-Hz bandwidth is achieved.

3.
J Stroke Cerebrovasc Dis ; 26(10): 2354-2361, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28648960

RESUMEN

BACKGROUND: The association between cholesteryl ester transfer protein (CETP) TaqIB polymorphism and ischemic stroke (IS) risk has generated conflicting results. To investigate whether the TaqIB polymorphism of the CETP gene was associated with the risk of IS, a meta-analysis was performed. METHODS: Studies were retrieved by searching PubMed, Web of Science, the Chinese National Knowledge Infrastructure, the Chinese Wanfang Database, and the Chinese VIP Database before January 16, 2017. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were used to assess the association. Depending on the heterogeneity the fixed-effects model or the random-effects model was used. RESULTS: A total of 6 case-control studies were identified with 1494 cases and 1370 controls. Overall, an association of CETP TaqIB polymorphism with IS was found in the 4 genetic models (B2B2 versus B1B1: OR = .63, 95% CI = .51-.79, P < .001; B1B2 + B2B2 versus B1B1: OR = .75, 95% CI = .64-.87, P < .001; B2B2 versus B1B2 + B1B1: OR = .70, 95% CI = .57-.85, P < .001; B2 versus B1: OR = .78, 95% CI = .70-.87, P < .001). In the subgroup analysis by ethnicity, similar risks were also observed in Asian population. CONCLUSIONS: This meta-analysis indicates that CETP TaqIB polymorphism is associated with IS risk, and the B2 allele is a protective factor for IS.


Asunto(s)
Isquemia Encefálica/genética , Proteínas de Transferencia de Ésteres de Colesterol/genética , Polimorfismo Genético , Accidente Cerebrovascular/genética , Isquemia Encefálica/etnología , Humanos , Accidente Cerebrovascular/etnología
4.
Immunopharmacol Immunotoxicol ; 38(2): 98-102, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26667579

RESUMEN

To elucidate the anti-inflammatory mechanisms involved, we investigated the effects of atractylenolide III (ATL-III) on cytokine expression, extracellular signal-regulated kinases 1 and 2 (ERK1/2), p38 mitogen-activated protein kinase (p38), C-Jun-N-terminal protein kinase1/2 (JNK1/2) and nuclear factor-κB (NF-κB) pathways in lipopolysaccharide (LPS)-induced RAW264.7 mouse macrophages. Macrophages were incubated with various concentrations (0, 25, 50, 100 µM) of ATL-III and/or LPS (1 µg/mL) for 24 h. The production of nitric oxide (NO) was determined by the Greiss reagent. The production of tumor necrosis factor alpha (TNF-α), prostaglandin E2 (PGE2) and interleukin 6 (IL-6) was determined by enzyme-linked immunosorbent assay (ELISA). Furthermore, macrophages were treated with ATL-III (0, 25, 100 µM) for 1 h and then stimulated by LPS. NF-κB, p38, JNK1/2 and ERK1/2 were determined by western blotting. We found ATL-III showed no inhibitory effect on cell proliferation at concentrations ranging from 1 µM to 100 µM. In addition, ATL-III decreased the release of NO, TNF-α, PGE2 and IL-6 in a dose-dependent manner and showed statistically significant at concentrations of 50 µM and 100 µM as well as cyclooxygenase-2 (COX-2) expression. Furthermore, ATL-III suppressed the transcriptional activity of NF-κB. ATL-III also inhibited the activation of ERK1/2, p38 and JNK1/2 in LPS-treated macrophages and showed statistically significant at concentrations of 25 µM and 100 µM. These data suggest that ATL-III shows an anti-inflammatory effect by suppressing the release of NO, PGE2, TNF-α and IL-6 related to the NF-κB- and MAPK-signaling pathways.


Asunto(s)
Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Lactonas/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Macrófagos/metabolismo , FN-kappa B/metabolismo , Sesquiterpenos/farmacología , Transducción de Señal/efectos de los fármacos , Animales , Línea Celular , Ciclooxigenasa 2/biosíntesis , Regulación de la Expresión Génica/efectos de los fármacos , Interleucina-6/biosíntesis , Lipopolisacáridos/farmacología , Ratones , Óxido Nítrico/biosíntesis , Transcripción Genética/efectos de los fármacos , Factor de Necrosis Tumoral alfa/biosíntesis
5.
Pharm Biol ; 53(4): 512-7, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25327442

RESUMEN

CONTEXT: Atractylodes macrocephala Koidz is a traditional herb. Atractylodes macrocephalaon polysaccharides (AMP) have been found to enhance immunity and improve heart function. However, the mechanisms of the immunomodulatory effect have not been investigated. OBJECTIVE: We examined whether AMP activated macrophages and explored the mechanisms of activation. MATERIALS AND METHODS: AMP was prepared and evaluated its immunomodulatory activity (25, 50, 100, and 200 µg/mL) by detecting the phagocytosis and the production of tumor necrosis factor-α (TNF-α), IFN-γ, and nitric oxide (NO) in RAW264.7 macrophages. Furthermore, the role of nuclear factor-κB (NF-κB) pathway was examined in regulating TNF-α and NO production. RESULTS: The phagocytosis of macrophages was enhanced by AMP in a dose-dependent manner and the maximal phagocytosis of macrophages occurred at concentrations of 100 and 200 µg/mL. NO, TNF-α, and IFN-γ release was also found to be dose dependent by increasing concentrations of AMP and reached the peak at a concentration of 200 µg/mL. In addition, AMP induced inhibitor kappaB (IκB) degradation and the activation of NF-κB by p65 nuclear translocation, and then the activation of NF-κB in nucleus peaked at a concentration of 200 µg/mL. Besides, NF-κB-specific inhibitor pyrrolidine dithiocarbamate (PDTC) decreased AMP-induced NO and TNF-α production. DISCUSSION AND CONCLUSION: These data suggest that AMP may modulate macrophage activities by stimulating NF-κB or activating NF-κB-dependent mechanisms.


Asunto(s)
Atractylodes/química , Medicamentos Herbarios Chinos/farmacología , Factores Inmunológicos/farmacología , Macrófagos/efectos de los fármacos , FN-kappa B/metabolismo , Polisacáridos/farmacología , Animales , Western Blotting , Línea Celular , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Medicamentos Herbarios Chinos/aislamiento & purificación , Ensayo de Inmunoadsorción Enzimática , Factores Inmunológicos/aislamiento & purificación , Interferón gamma/inmunología , Interferón gamma/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Óxido Nítrico/biosíntesis , Fagocitosis/efectos de los fármacos , Fagocitosis/inmunología , Polisacáridos/aislamiento & purificación , Transducción de Señal , Factor de Necrosis Tumoral alfa/inmunología , Factor de Necrosis Tumoral alfa/metabolismo
6.
Nanotechnology ; 25(25): 255102, 2014 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-24896735

RESUMEN

Incorporating ligands with nanoparticle-based carriers for specific delivery of therapeutic nucleic acids (such as antisense oligonucleotides and siRNA) to tumor sites is a promising approach in anti-cancer strategies. However, nanoparticle-based carriers remain insufficient in terms of the selectivity and transfection efficiency. In this paper, we designed a dual receptor-targeted QDs gene carrier QD-(AS-ODN+GE11+c(RGDfK)) which could increase the cellular uptake efficiency and further enhance the transfection efficiency. Here, the targeting ligands used were peptides GE11 and c(RGDfK) which could recognize epidermal growth factor receptors (EGFR) and integrin ανß3 receptors, respectively. Quantitative flow cytometry and ICP/MS showed that the synergistic effect between EGFR and integrin ανß3 increased the cellular uptake of QDs carriers. The effects of inhibition agents showed the endocytosis pathway of QD-(AS-ODN+GE11+c(RGDfK)) probe was mainly clathrin-mediated. Western blot confirmed that QD-(AS-ODN+GE11+c(RGDfK)) could further enhance gene silencing efficiency compared to QD-(AS-ODN+GE11) and QD-(AS-ODN+c(RGDfK)), suggesting this dual receptor-targeted gene carrier achieved desired transfection efficiency. In this gene delivery system, QDs could not only be used as a gene vehicle but also as fluorescence probe, allowing for localization and tracking during the delivery process. This transport model is very well referenced for non-viral gene carriers to enhance the targeting ability and transfection efficiency.


Asunto(s)
Oligonucleótidos Antisentido/química , Oligonucleótidos Antisentido/farmacología , Puntos Cuánticos/química , Transfección/métodos , Biotina/química , Western Blotting , Línea Celular Tumoral , Receptores ErbB/genética , Receptores ErbB/metabolismo , Citometría de Flujo , Silenciador del Gen , Técnicas de Transferencia de Gen , Células HeLa , Humanos , Integrina alfaVbeta3/genética , Integrina alfaVbeta3/metabolismo , Células MCF-7 , Microscopía Confocal , Péptidos/genética , ARN Interferente Pequeño/química , ARN Interferente Pequeño/farmacología , Estreptavidina/química
7.
Ying Yong Sheng Tai Xue Bao ; 35(7): 1988-1996, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39233429

RESUMEN

Studying the stoichiometric characteristics of soil nutrients aids in evaluating soil quality and deciphering the coupling of soil nutrients. The influence of migratory bird activities on the dynamics of wetland soil nutrients and their stoichiometric remains unclear. We classified the central, peripheral and adjacent natural grassy areas as severe, mild, and no bird activity (control), respectively, in Donghu Carex meadow, a representative migratory bird habitat in Poyang Lake, based on flock characteristics and initial surveys. We analyzed the contents and stoichio-metry of soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) across soil depths of 0-100 cm under different intensities of migratory bird activities. The results showed that the activities of migratory birds significantly impacted nutrient levels exclusively within 0-30 cm soil. Mild activities markedly enhanced SOC and TN across 0-30 cm soil, while both mild and severe activities significantly raised TP within the same depth. For the 0-100 cm soil profiles, soil C/N ratios were 10.0, 10.8, and 9.9, C/P ratios were 23.5, 30.0, and 22.7, and N/P ratios were 2.3, 2.7, and 2.3 under no, mild, and severe bird activities, respectively. Further, mild activities of migratory birds significantly increased soil C/N, C/P and N/P ratios only within the 0-30 cm depth, while the stoichiometric ratios of all soil layer had no significant difference under severe bird activity. Soil stoichiometric ratios strongly correlated with physicochemical properties. SOC, TN, and TP primarily mediated the effects of migratory bird activity on soil carbon, nitrogen, and phosphorus stoichiometric ratios in Poyang Lake wetland. In conclusion, the influence of migratory bird activity on the stoichiometric ratios of soil carbon, nitrogen, and phosphorus in Poyang Lake wetland exhibited depth threshold (approximately 30 cm), aligning with the "Intermediate Distur-bance Hypothesis". These findings could provide a new perspective for the protection of wetlands and migratory birds.


Asunto(s)
Migración Animal , Aves , Carbono , Lagos , Nitrógeno , Fósforo , Suelo , Humedales , Animales , Fósforo/análisis , Nitrógeno/análisis , Suelo/química , China , Carbono/análisis , Lagos/química , Carex (Planta)/crecimiento & desarrollo , Carex (Planta)/metabolismo , Monitoreo del Ambiente , Ecosistema
8.
Biosensors (Basel) ; 14(6)2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38920565

RESUMEN

Hydrogen peroxide (H2O2) is a signaling molecule that has the capacity to control a variety of biological processes in organisms. Cancer cells release more H2O2 during abnormal tumor growth. There has been a considerable amount of interest in utilizing H2O2 as a biomarker for the diagnosis of cancer tissue. In this study, an electrochemical sensor for H2O2 was constructed based on 3D reduced graphene oxide (rGO), MXene (Ti3C2), and multi-walled carbon nanotubes (MWCNTs) composite. Three-dimensional (3D) rGO-Ti3C2-MWCNTs sensor showed good linearity for H2O2 in the ranges of 1-60 µM and 60 µM-9.77 mM at a working potential of -0.25 V, with sensitivities of 235.2 µA mM-1 cm-2 and 103.8 µA mM-1 cm-2, respectively, and a detection limit of 0.3 µM (S/N = 3). The sensor exhibited long-term stability, good repeatability, and outstanding immunity to interference. In addition, the modified electrode was employed to detect real-time H2O2 release from cancer cells and cancer tissue ex vivo.


Asunto(s)
Técnicas Biosensibles , Electrodos , Grafito , Peróxido de Hidrógeno , Nanotubos de Carbono , Neoplasias , Nanotubos de Carbono/química , Grafito/química , Humanos , Neoplasias/diagnóstico , Técnicas Electroquímicas , Límite de Detección
9.
Analyst ; 137(1): 49-58, 2012 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-22081036

RESUMEN

Due to the significance of hydrogen peroxide (H(2)O(2)) in biological systems and its practical applications, the development of efficient electrochemical H(2)O(2) sensors holds a special attraction for researchers. Various materials such as Prussian blue (PB), heme proteins, carbon nanotubes (CNTs) and transition metals have been applied to the construction of H(2)O(2) sensors. In this article, the electrocatalytic H(2)O(2) determinations are mainly focused on because they can provide a superior sensing performance over non-electrocatalytic ones. The synergetic effect between nanotechnology and electrochemical H(2)O(2) determination is also highlighted in various aspects. In addition, some recent progress for in vivo H(2)O(2) measurements is also presented. Finally, the future prospects for more efficient H(2)O(2) sensing are discussed.


Asunto(s)
Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Peróxido de Hidrógeno/análisis , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/tendencias , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/tendencias , Ferrocianuros/química , Hemoproteínas/química , Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/metabolismo , Nanotubos de Carbono/química , Elementos de Transición/química
10.
Ginekol Pol ; 93(8): 605-613, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35315012

RESUMEN

OBJECTIVES: Open power morcellation during a laparoscopic myomectomy (LM) can result in the dissemination of benign or occult malignant tumor cells in the abdominopelvic cavity. The development of a new contained collection bag for power morcellation is now favored by gynecologic surgeons worldwide. MATERIAL AND METHODS: This study was a single-arm trial comprising 20 women who consecutively underwent an LM involving the use of a newly designed contained collection bag for power morcellation between November 3rd 2017 and April 31st 2018. There was also a historical control group consisting of 30 women who underwent open power morcellation during an LM between May 1st 2017 and October 31st 2017. All the essential information concerning the patients and surgically related data, including the myoma size, the operation duration, and the cell count of the intraperitoneal irrigating fluid, were collected and analyzed. RESULTS: The uterus size and the maximum diameters of the uterus and the myoma of the two groups were not significantly different (p = 0.65, p = 0.71, and p = 0.31, respectively). Pseudopneumoperitoneum was established and clear visualization was guaranteed in all 20 cases in the experimental group. The remaining fragment tissue amount (mean ± SD) and weight (mean ± SD) in the collection bag after morcellation in the experimental group were 5.00 ± 1.48 and 3.87 ± 1.31 (g). All the collection bags were routinely examined after the LM using normal saline, and no leaks or lesions were found. The cell counts of the intraperitoneal irrigating fluid both before and after morcellation were less than 105-106/L. The pathology of all the tissues confirmed that there were no malignant tumors. The operation of the experimental group was 18 mins longer than that of the historical control group (p = 0.00). CONCLUSIONS: This newly designed collection bag system for LM morcellation is effective, feasible, and safe.


Asunto(s)
Laparoscopía , Leiomioma , Morcelación , Mioma , Miomectomía Uterina , Neoplasias Uterinas , Femenino , Humanos , Histerectomía , Leiomioma/cirugía , Leiomioma/patología , Morcelación/efectos adversos , Solución Salina , Neoplasias Uterinas/cirugía , Neoplasias Uterinas/patología
11.
Microorganisms ; 10(1)2022 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-35056580

RESUMEN

Although microorganisms play a key role in the carbon cycle of the Poyang Lake wetland, the relationship between soil microbial community structure and organic carbon characteristics is unknown. Herein, high-throughput sequencing technology was used to explore the effects of water level (low and high levels above the water table) and vegetation types (Persicaria hydropiper and Triarrhena lutarioriparia) on microbial community characteristics in the Poyang Lake wetland, and the relationships between soil microbial and organic carbon characteristics were revealed. The results showed that water level had a significant effect on organic carbon characteristics, and that soil total nitrogen, organic carbon, recombinant organic carbon, particle organic carbon, and microbial biomass carbon were higher at low levels above the water table. A positive correlation was noted between soil water content and organic carbon characteristics. Water level and vegetation type significantly affected soil bacterial and fungal diversity, with water level exerting a higher effect than vegetation type. The impacts of water level and vegetation type were higher on fungi than on bacteria. The bacterial diversity and evenness were significantly higher at high levels above the water table, whereas an opposite trend was noted among fungi. The bacterial and fungal richness in T. lutarioriparia community soil was higher than that in P. hydropiper community soil. Although both water level and vegetation type had significant effects on bacterial and fungal community structures, the water level had a higher impact than vegetation type. The bacterial and fungal community changes were the opposite at different water levels but remained the same in different vegetation soils. The organic carbon characteristics of wetland soil were negatively correlated with bacterial diversity but positively correlated with fungal diversity. Soil water content, soluble organic carbon, C/N, and microbial biomass carbon were the key soil factors affecting the wetland microbial community. Acidobacteria, Alphaproteobacteria, Verrucomicrobia, Gammaproteobacteria, and Eurotiomycetes were the key microbiota affecting the soil carbon cycle in the Poyang Lake wetland. Thus, water and carbon sources were the limiting factors for bacteria and fungi in wetlands with low soil water content (30%). Hence, the results provided a theoretical basis for understanding the microbial-driven mechanism of the wetland carbon cycle.

12.
PeerJ ; 8: e9443, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32974090

RESUMEN

BACKGROUND: The distribution and use of camphor (Cinnamomum camphora L.) trees are constrained by increasing soil salinity in south-eastern China along the Yangtze River. However, the response mechanism of this species to salinity, especially in team of photosynthesis, are unknown. METHODS: Here, we analysed themorphological, physiological, ultrastructural, and proteomic traits of camphor seedlings under NaCl (103.45 mM) treatment in pot experiments for 80 days. RESULTS: The growth was limited because of photosynthetic inhibition, with the most significant disturbance occurring within 50 days. Salinity caused severe reductions in the leaf photosynthetic rate (A n), stomatal conductance (g s), maximal chlorophyll fluorescence (Fm), maximum quantum yield of PSII (Fv/Fm), non-photochemical quenching (NPQ), relative quantum efficiency of PSII photochemistry (ΦPSII), photochemical quenching coefficient (qP) and photo-pigment contents (chlorophyll a (Cha), chlorophyll b (Chb), total chlorophyll (Chl)); weakened the antioxidant effects, including those of malondialdehyde (MDA), superoxide dismutase (SOD) and peroxidase (POD); and injured chloroplasts. The physiologicalresults indicated that the main reason for photo-inhibition was oxidative factors induced by NaCl. The proteomic results based on isobaric tags for relative and absolute quantitation (iTRAQ) further confirmedthat photosynthesis was the most significant disrupted process by salinity (P < 0.01) and there were 30 downregulated differentially expression proteins (DEPs) and one upregulated DEP related to restraint of the photosynthetic system, which affected photosystem I, photosystem II, the Cytochrome b6/f complex, ATP synthase and the light-harvesting chlorophyll protein complex. In addition, 57 DEPs were related to photo-inhibition by redox effect and 6 downregulated DEPs, including O2 evolving complex 33kD family protein (gi-224094610) and five other predicted proteins (gi-743921083, gi-743840443, gi-743885735, gi-743810316 and gi-743881832) were directly affected. This study provides new proteomic information and explains the possible mechanisms of photo-inhibition caused by salinity on C. camphor.

13.
Pediatr Pulmonol ; 52(4): 423-429, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27551963

RESUMEN

BACKGROUND: As for the association of vitamin D receptor (VDR) gene polymorphisms with susceptibility to pediatric asthma, results of published studies yielded conflicts. A systematic review was conducted on the relationship between childhood asthma and VDR gene polymorphisms, including ApaI (rs7975232), BsmI (rs1544410), FokI (rs2228570), and TaqI (rs731236). METHODS: PubMed, Web of Science, CBM (Chinese Biomedical Database), CNKI (China National Knowledge Infrastructure), and Wanfang (Chinese) database were searched for relevant studies. Pooled odds ratios (OR) with 95% confidence interval (CI) were calculated. RESULTS: Overall results suggested that there was a statistically significant association between ApaI polymorphism and childhood asthma in homozygote model (OR = 1.674, 95%CI = 1.269-2.208, P < 0.001) and allele model (OR = 1.221, 95%CI = 1.084-1.375, P = 0.001). Stratification by ethnicity revealed a statistical association in Asians (OR = 1.389, 95%CI = 1.178-1.638, P < 0.001). There was some evidence of an association between BsmI polymorphism and childhood asthma in the homozygote (OR = 1.462, 95%CI = 1.016-2.105, P = 0.041) and allele models (OR = 1.181, 95%CI = 1.006-1.386, P = 0.042). This association reached significance only in the Caucasian group (OR = 1.236, 95%CI = 1.029-1.485, P = 0.023). For FokI, a statistical association was detected in dominant model (OR = 1.281, 95%CI = 1.055-1.555, P = 0.012); this association was significant in allele model (OR = 1.591, 95%CI = 1.052-2.405, P = 0.028) in Caucasian. CONCLUSION: ApaI polymorphism plays a particular role in childhood asthma in Asians. FokI polymorphism may be connected with pediatric asthma in Caucasian population. And BsmI polymorphism marginally contributes to childhood asthma susceptibility, while there might be no association between TaqI polymorphism and childhood asthma risk. Pediatr Pulmonol. 2017;52:423-429. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Asma/genética , Predisposición Genética a la Enfermedad , Receptores de Calcitriol/genética , Pueblo Asiatico , Niño , Homocigoto , Humanos , Oportunidad Relativa , Polimorfismo Genético , Riesgo , Población Blanca
14.
Biosens Bioelectron ; 50: 318-24, 2013 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-23876543

RESUMEN

Single-walled carbon nanotubes (SWCNTs) and hemoglobin (Hb) modified carbon fiber ultramicroelectrode (CFUME) were employed to construct a direct electron transfer based in vivo H2O2 sensor. At the low working potential of -0.1 V, Hb/SWCNTs/CFUME showed a dynamic range up to 0.405 mM with a low detection limit of 4 µM (S/N=3) and a high sensitivity of 1.07 log(A) log(M)(-1) cm(-2). The apparent Michaelis-Menten constant (Km, app) was estimated to be as low as 1.35 mM. Due to the extremely small dimension and low working potential, Hb/SWCNTs/CFUME could give directly amperometric in vivo monitoring of H2O2 in aloe leaves with salt stress for 19.5h without the requirement of complex data processing and extra surface coatings to avoid interferences. The sharp increase of H2O2 level in aloe leaves with salt stress was clearly observed using Hb/SWCNTs/CFUME from 12.5 h, while in the aloe without salt stress, H2O2 level remained stable in the whole measurement. For further confirming the in vivo response of Hb/SWCNTs/CFUME, catalase (CAT) was injected into the spot adjacent to the sensor and caused rapid current decrease, which suggests the scavenging of H2O2. These results indicate that Hb/SWCNTs/CFUME can be a powerful tool for in vivo investigation of ROS.


Asunto(s)
Aloe/fisiología , Técnicas Biosensibles/instrumentación , Carbono/química , Peróxido de Hidrógeno/análisis , Nanotubos de Carbono/química , Aloe/química , Fibra de Carbono , Hemoglobinas/química , Peróxido de Hidrógeno/metabolismo , Microelectrodos , Presión Osmótica , Hojas de la Planta/química , Hojas de la Planta/fisiología , Salinidad , Estrés Fisiológico
15.
Fertil Steril ; 95(8): 2687-9, 2011 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-21616486

RESUMEN

Primary human endometrial cells were exposed to hypoxia preconditioning (HPC), HPC-hypoxia, and hypoxia conditions, and then endometrial tissue treated with ischemia preconditioning (IPC) was transplanted onto the chick embryo chorioallantoic membrane to investigate the role of slight ischemia of endometrium in the pathologic process of endometriosis. IPC up-regulated vascular endothelial growth factor expression and decreased apoptosis of endometrial cells, thus facilitating the endometrial fragments' ectopic implantation.


Asunto(s)
Membrana Corioalantoides/irrigación sanguínea , Endometriosis/metabolismo , Endometrio/metabolismo , Precondicionamiento Isquémico/métodos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Adulto , Animales , Apoptosis , Hipoxia de la Célula , Proliferación Celular , Células Cultivadas , Embrión de Pollo , Constricción , Endometriosis/patología , Endometriosis/fisiopatología , Endometrio/irrigación sanguínea , Endometrio/patología , Endometrio/trasplante , Femenino , Humanos , Microvasos/fisiopatología , Persona de Mediana Edad , Factores de Tiempo , Regulación hacia Arriba , Arteria Uterina/cirugía
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