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1.
Ecotoxicol Environ Saf ; 272: 116036, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38325271

RESUMO

Microplastics (MPs) weather after entering the environment gradually, and the interaction with metal ions in the aqueous environment has received extensive attention. However, there are few studies on Hg(Ⅱ), especially the effect of MPs on the release of Hg0(DEM) in water after entering the aqueous environment. In this study, four types of MPs (PP, PE, PET, PVC) were selected to study the adsorption and desorption behavior of Hg(Ⅱ) after photoaging and to explore the influence of MPs on the release of DEM in seawater under different lighting conditions. The results showed that the specific surface area, negative charges, and oxygen-containing functional group of MPs increased after aging. The adsorption capacity of aged MPs for Hg(Ⅱ) was significantly improved, which was consistent with the pseudo-first-order and pseudo-second-order model, indicating that the adsorption process was a chemical and physical adsorption. The fitting results of the in-particle diffusion model indicated that the adsorption was controlled by multiple steps. Hg(Ⅱ) was easier to desorb in the simulated gastric fluid environment. Because the aged MPs had the stronger binding force to Hg(Ⅱ), their desorption rate is lower than new MPs. Under visible light and UVA irradiation, MPs inhibited the release of Hg0. Under UVA, the mass of DEM produced in seawater with aged PE and PVC was higher than that of new PE and PVC. The aged PE and PVC could produce more ·O2-, which was conducive to the reduction of mercury. However, in UVB irradiation, the addition of MPs promoted the release of DEM, and ·O2- also played an important contribution in affecting the photochemical reaction of mercury. Therefore, the presence of aged MPs will significantly affect the water-air exchange of Hg in water. Compared with new MPs, aged MPs improved the contribution of free radicals in Hg transformation by releasing reactive oxygen species. This study extends the understanding of the effects of MPs on the geochemical cycle of Hg(Ⅱ) in seawater, better assesses the potential combined ecological risks of MPs and Hg(Ⅱ), and provides certain guidance for the pollution prevention and control of MPs.


Assuntos
Mercúrio , Poluentes Químicos da Água , Microplásticos , Plásticos , Adsorção , Água do Mar , Elementos Químicos , Água , Poluentes Químicos da Água/análise
2.
Heliyon ; 9(1): e12662, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36691523

RESUMO

Background: Left atrial appendage (LAA) closure (LAAC) in atrial fibrillation (AF) patients with the reversed chicken-wing (RCW) LAA is challenging. Aims: To elucidate the LAAC strategy of the RCW-LAA. Methods: A total of 802 AF patients who were enrolled in the LAACablation registry for LAAC procedure were included, 55 of whom presented with the RCW-LAA. The WATCHMAN device was implanted using the standard protocol when the sheath depth was no less than the device depth (the simple group). For those with a sheath depth of less than the device depth (the complex group), device deployment was attempted with acceptable protrusion or after a repeated atrial transseptal puncture (re-ATP) at a more inferior and anterior position. The anatomical and procedural features were compared between groups and before and after the re-ATP. Results: The success rate of LAAC was significantly lower in patients with the RCW-LAA than with the other morphologies (92.7% vs. 98.8%, p = 0.001). Compared with the simple group, the complex group had shorter root depth and shorter neck length, and more LAAs in the complex group were at lower position (all p < 0.05). The sheath depth after the re-ATP was significantly greater than that before the re-ATP (18.8 ± 3.4 mm vs. 14.7 ± 2.6 mm, p < 0.001). For the patients who underwent re-ATP, the sheath went significantly deeper in successful procedures than in aborted procedures (19.7 ± 3.3 mm vs. 15.8 ± 1.8 mm, p = 0.040). Conclusions: The anatomical features of the RCW-LAA were related to the complexity of the LAAC procedure. The re-ATP at an inferior and anterior location could increase the success rate of LAAC. ClinicalTrialsgov: NCT03788941.

3.
Membranes (Basel) ; 12(10)2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36295770

RESUMO

Nanofiltration (NF) membranes with a high permeability and rejection are of great interest in desalination, separation and purification. However, how to improve the permeation and separation performance still poses a great challenge in the preparation of NF membranes. Herein, the novel composite NF membrane was prepared through the interfacial polymerization of M-phenylenediamine (MPD) and trimesoyl chloride (TMC) on a double-walled carbon nanotube (DWCNT) interlayer supported by PES substrate. The DWCNT interlayer had a great impact on the polyamide layer formation. With the increase of the DWCNT dosage, the XPS results revealed an increase in the number of carboxyl groups, which decreased the crosslinking degree of the polyamide layer. Additionally, the AFM results showed that the surface roughness and specific surface area increased gradually. The water flux of the prepared membrane increased from 25.4 L/(m2·h) and 26.6 L/(m2·h) to 109 L/(m2·h) and 104.3 L/(m2·h) with 2000 ppm Na2SO4 and NaCl solution, respectively, under 0.5 MPa. Meanwhile, the rejection of Na2SO4 and NaCl decreased from 99.88% and 99.38% to 96.48% and 60.47%. The proposed method provides a novel insight into the rational design of the multifunctional interlayer, which shows great potential in the preparation of high-performance membranes.

4.
Nat Commun ; 13(1): 5336, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36088436

RESUMO

The formation and distribution of lunar surficial water remains ambiguous. Here, we show the prominence of water (OH/H2O) attributed to solar wind implantation on the uppermost surface of olivine, plagioclase, and pyroxene grains from Chang'E-5 samples. The results of spectral and microstructural analyses indicate that solar wind-derived water is affected by exposure time, crystal structure, and mineral composition. Our estimate of a minimum of 170 ppm water content in lunar soils in the Chang'E-5 region is consistent with that reported by the Moon Minerology Mapper and Chang'E-5 lander. By comparing with remote sensing data and through lunar soil maturity analysis, the amount of water in Chang'E-5 provides a reference for the distribution of surficial water in middle latitude of the Moon. We conclude that minerals in lunar soils are important reservoirs of water, and formation and retention of water originating from solar wind occurs on airless bodies.

5.
BMC Surg ; 22(1): 297, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35909183

RESUMO

BACKGROUND: The purpose of this study was to determine how the drain fluid volume on the first day after surgery (DFV 1) can be used to predict clinically relevant post-operative pancreatic fistula following distal pancreatectomy (DP). METHOD: A retrospective analysis of 175 patients who underwent distal pancreatectomy in hepatobiliary surgery at Chengdu 363 Hospital (China) from January 2015 to January 2021 has been performed. Depending on the presence of pancreatic fistula, all patients were divided into two groups: POPF and non-POPF. The clinical factors were analyzed using SPSS 17.0 and Medcalc software. In order to assess the effectiveness of DFV 1 in predicting POPF after surgery, ROC curves were used to calculate its cut-off point,, which yielded sensitivity and negative predictive value of 100% for excluding POPF. RESULT: Of the 175 patients who underwent distal pancreatectomy, the incidence of overall pancreatic fistula was 36%, but the rate of clinically significant (grade B and C) fistula, as defined by the International Study Group on Pancreatic Fistula, 30 was only 17.1% (28 grade B and 2 grade C fistula). The results from univariate and multivariate logistic regression analysis showed that drain fluid volume on the first postoperative day (OR = 0.95, P = 0.03), drainage fluid amylase level on POD1 (OR = 0.99, P = 0.01) and the preoperative ALT level (OR = 0.73, P = 0.02) were independent risk factors associated with CR-POPF. Receiver operating characteristic (ROC) curve analysis revealed that a drainage volume of 156 mL within 24 h and an amylase greater than 3219.2 U/L on the first postoperative day were the optimal thresholds associated with complications. CONCLUSION: After distal pancreatectomy, the drainage volume on the first postoperative day can predict the presence of a clinically relevant pancreatic fistula.


Assuntos
Drenagem , Pancreatectomia , Fístula Pancreática , Amilases , Drenagem/métodos , Humanos , Pancreatectomia/métodos , Fístula Pancreática/diagnóstico , Fístula Pancreática/epidemiologia , Pancreaticoduodenectomia/métodos , Complicações Pós-Operatórias/diagnóstico , Valor Preditivo dos Testes , Estudos Retrospectivos
6.
Sci Total Environ ; 822: 153304, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35090923

RESUMO

Basalt-derived soils are widespread worldwide. Such soils contain high levels of heavy metals like chromium (Cr), which is a serious environmental concern. However, little is known regarding the enrichment and speciation of Cr during the basalt weathering process. Therefore, two basalt-derived soil profiles (Nitisol and Ferralsol) in the Leizhou Peninsula, south tropical China, were investigated to explore the redistribution and transformation of Cr during basalt weathering. All profiles could be divided into three layers: rocks, saprolites, and soils. The Nitisol and Ferralsol profiles exhibited strong (kaolinization) and extreme (laterization) degrees of weathering, respectively. Results showed that Cr concentrations in the saprolites (234 to 315 mg·kg-1) were higher than those in basalt rocks (139 to 159 mg·kg-1), indicating that Cr was enriched with the continuous loss of Si and other mobile macro-elements. While high levels of Cr were also enriched in the soils (178 to 430 mg·kg-1) accompanied with Fe. However, in the upper soils of the Ferralsol profile, the acidity and organic matter could promote the leaching of Cr. Geochemical fractions and EPMA mapping showed that chromite and olivine were the main Cr-bearing minerals in basalt, but Fe-oxides (e.g., goethite and hematite) contained the highest portion of Cr in weathered saprolites and soils. The availability of Cr in the soil was extremely low due to the high stability of Cr bound to Fe-oxides. However, the decreasing contents of Cr bound to Fe-oxides in the upper soils of the Ferralsol profile indicated that Cr could also be released during Fe leaching. In conclusion, the weathering of basalt can lead to the enrichment of Cr in Fe-(hydro)oxides, which are the main controlling minerals for Cr mobility in basalt-derived soils. Further research is needed to evaluate the effect of Fe-(hydro)oxide formation and dissolution on the release of soil Cr.


Assuntos
Cromo , Poluentes do Solo , China , Cromo/análise , Monitoramento Ambiental , Silicatos , Solo/química , Poluentes do Solo/análise
7.
Eur J Pharmacol ; 855: 244-251, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31075240

RESUMO

Coronary microembolization (CME) is responsible for a substantial fraction of microvascular obstruction (MVO), which are strongly associated with mortality and hospitalization for heart failure within 1 year after primary percutaneous coronary intervention (PCI) in ST-segment elevation myocardial infarction (STEMI). However, the effect of miRNA on cardiomyocyte apoptosis in a CME model has been less well-studied. miRNA sequencing analysis was performed to examine differentially expressed miRNAs induced by CME in rats. Phosphatase and tensin homologue (PTEN) 3 'RACE and dual-luciferase reporter assays were performed to confirm that PTEN is a direct target gene of miR-486-5p. miRNA-486-5p overexpression was established by injecting AAV into rats via the tail vein. The CME model was established by injecting microspheres into the left ventricle of rats. 6h after surgery, cardiac function, microinfarct area, and the apoptotic index were determined. RT-PCR was used to evaluate mRNA level and Western blotting was used to evaluate protein expression. miRNA sequencing data showed that there were 5 upregulated and 8 downregulated miRNAs, and the relative expression of miRNA-486-5p was significantly downregulated. PTEN 3'RACE and dual-luciferase reporter assays confirmed that miR-486-5p directly targets the rat PTEN gene. The expression of miR-486-5p gradually declined, however, the expression of PTEN mRNA rapidly increased at early time points after CME. Overexpression of miR-486-5p reduced cardiomyocyte apoptosis and improved cardiac function through inhibition of PTEN and activation of the PI3K/Akt pathway in rat CME models. Overexpression of miR-486-5p, which targets PTEN, protects against CME-induced cardiomyocyte apoptosis and improves cardiac function in rats by activating the PI3K/Akt pathway.


Assuntos
Apoptose/genética , Embolização Terapêutica/efeitos adversos , MicroRNAs/genética , Miócitos Cardíacos/metabolismo , PTEN Fosfo-Hidrolase/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Vasos Coronários/cirurgia , Regulação para Baixo , Masculino , Miócitos Cardíacos/patologia , Ratos , Ratos Sprague-Dawley
8.
Cell Physiol Biochem ; 49(6): 2138-2150, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30257237

RESUMO

BACKGROUND/AIMS: Microvascular obstruction (MVO), an undesirable complication of percutaneous coronary intervention, is independently associated with adverse left ventricle remodeling and poor prognosis after acute myocardial infarction. Hypoxia and oxidative stress major roles in the pathophysiology of MVO. Pim1 serves an important protective role in the ischemic myocardium, but the underlying mechanisms remain poorly defined. Autophagy in early hypoxia or during moderate oxidative stress has been demonstrated to protect the myocardium. In this study, we investigated the association between the protective effect of Pim1 and autophagy after hypoxia and oxidative stress. METHODS: Ventricular myocytes from neonatal rat heart (NRVMs) were isolated. NRVMs were exposed to hypoxia and H2O2. Rapamycin and 3-methyladenine (3-MA) were used as an activator and inhibitor of autophagy, respectively. pHBAd-Pim1 was transfected into NRVMs. We assessed cardiomyocyte apoptosis by Annexin V-FITC/PI flow cytometry. Autophagy was evaluated by mRFP-GFP-LC3 adenovirus infection by confocal microscopy. Western blotting was used to quantify apoptosis or autophagy protein (caspase-3, LC3, P62, AMPK, mTOR, ATG5) concentrations. RESULTS: Autophagy and apoptosis in NRVMs significantly increased and peaked at 3 h and 6 h, respectively, after exposure to hypoxia and H2O2. The mTOR inhibitor rapamycin induced autophagy and decreased cardiomyocyte apoptosis, but the autophagy inhibitor 3-MA decreased autophagy and increased apoptosis at 3 h after exposure to hypoxia and H2O2. Pim1 levels in NRVMs increased at 3 h and decreased gradually after exposure to hypoxia and H2O2. Pim1 overexpression enhanced autophagy and decreased apoptosis. Pim1-induced promotion of autophagy is partly the result of activation of the AMPK/mTOR/ATG5 pathway after exposure to hypoxia and H2O2. CONCLUSION: Our results revealed that Pim1 overexpression prevented NRVMs from apoptosis via upregulating autophagy after exposure to hypoxia and oxidative stress, partly through activation of the AMPK/mTOR/ATG5 autophagy pathway.


Assuntos
Autofagia , Hipóxia Celular , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-pim-1/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Proteína 5 Relacionada à Autofagia/metabolismo , Células Cultivadas , Peróxido de Hidrogênio/farmacologia , Proteínas Associadas aos Microtúbulos/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-pim-1/genética , Ratos , Proteína Sequestossoma-1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Regulação para Cima/efeitos dos fármacos
9.
J Struct Biol ; 203(2): 162-169, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29715524

RESUMO

Avian eggshell is a typical bio-engineered ceramics characterized by layer structures. These layers are categorized mainly by the form of crystalline calcite. Whether there exist other layer structures, how the membrane layer is transformed to the carbonate one, what form the carbonate takes after the transition. These questions remain to be clarified. Here we examine the eggshell of chicken Gallus domesticus by optical microscope, scanning electron microscope and transmission electron microscope. We find that there exists another layer structure defined by variation of organic matrices. The transition from the membrane to the mammillary cones is implemented through the calcium reserve assemblies or the mammillary cores. The integrity of the transitional structure was weakens as the reserved calcium is displaced, and loses completely in about 10 days of incubation. As the first deposited carbonate layer after the transition, the mammillary cones comprise amorphous calcium carbonate and clusters/assemblies of calcite crystallites the size about a nanometer, plus bubble pores extending preferentially in the lateral direction. Our results provide new insights into the structure and component of the avian eggshell, and may help decipher the constitution of the bio-ceramics in the perspective of material science.


Assuntos
Casca de Ovo , Animais , Carbonato de Cálcio/química , Galinhas , Microscopia , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão
10.
PeerJ ; 5: e3108, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28344907

RESUMO

Apoptosis of lymphocytes is associated with immunosuppression and poor prognosis in sepsis. Our previous report showed that histones, nuclear proteins released from damaged or dying cells in sepsis, can mediate lymphocyte apoptosis via mitochondria damage. Grape seed proanthocyanidin extract (GSPE), a natural substance with protective properties against oxidative stress, plays a vital role in cell and mitochondria protection. We thus hypothesized that GSPE may play a protective role in histone-induced lymphocyte apoptosis through its anti-oxidative properties. In this study, we investigated the protective efficacy of GSPE on lymphocyte apoptosis induced by extracellular histones, a main contributor of death in sepsis. Human blood lymphocytes were treated with 50 µg/ml histones, 2 µg/ml GSPE, or a combination of both. A total of 100 µM N-acetylcysteine (NAC), a reactive oxygen species (ROS) inhibitor, was used as a positive control for GSPE. Apoptosis, intracellular ROS levels, mitochondrial membrane potential, Bcl-2 expression, and caspase-3 cleavage were measured. Our data clearly indicate that GSPE significantly inhibited lymphocyte apoptosis, generation of ROS, the loss of mitochondrial membrane potential, the decrease in Bcl-2 expression, and caspase-3 activation induced by extracellular histones. In conclusion, we show that GSPE has a protective effect on lymphocyte apoptosis induced by extracellular histones. This study suggests GSPE as a potential therapeutic agent that could help reduce lymphocyte apoptosis, and thus the state of immunosuppression was observed in septic patients.

11.
Sensors (Basel) ; 15(9): 23126-44, 2015 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-26378546

RESUMO

Microbial fuel cells (MFCs) are of increasing interest as bioelectrochemical systems for decomposing organic materials and converting chemical energy into electricity. The main challenge for this technology is that the low power and voltage of the devices restricts the use of MFCs in practical applications. In this paper, a power management system (PMS) is developed to store the energy and export an increased voltage. The designed PMS successfully increases the low voltage generated by an individual MFC to a high potential of 5 V, capable of driving a wireless temperature and humidity sensor based on nRF24L01 data transmission modules. With the PMS, MFCs can intermittently power the sensor for data transmission to a remote receiver. It is concluded that even an individual MFC can supply the energy required to power the sensor and telemetry system with the designed PMS. The presented PMS can be widely used for unmanned environmental monitoring such as wild rivers, lakes, and adjacent water areas, and offers promise for further advances in MFC technology.


Assuntos
Fontes de Energia Bioelétrica , Monitoramento Ambiental/métodos , Telemetria/métodos , Umidade , Temperatura
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(12): 3296-9, 2015 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-26964197

RESUMO

Abstract Highly efficient bilayer-structure yellow-green organic light-emitting device (OLED) has been demonstrated based on MADN as hole-transport layer (HTL) and host-guest coped system of [Alq3: 0.7 Wt% rubrene] as emitting and electron-trans- port layer. The device gives yellow-green emission through incomplete energy transfer from the host of Alq3 to the guest of ru- brene. An electroluminescent peak of 560 nm, 1931 CIE color coordinates of (0.46, 0.52) and a maximum current efficiency of 7.63 cd · A⁻¹ (which has been enhanced by 30% in comparison with the counterpart having conventional NPB HTL) are ob- served. The hole-transporting characteristics of MADN and NPB have been systematically investigated by constructing hole-only devices and employing impedance spectroscopy analysis. Our results indicate that MADN can be served as an effective hole-trans- port material and its hole-transporting ability is slightly inferior to NPB. This overcomes the shortcoming of hole transporting more quickly than electron in OLED and improves carrier balance in the emitting layer. Consequently, the device current efficien- cy is promoted. In addition, the current efficiency of bilayer-structure OLED with MADN as HTL is comparable to that of conv- entinol trilayer-structure device with MADN as HTL and Alq3 as electron-transport layer. This indicates that the simplified bi- layer-structure device can be achieved without sacrificing current efficiency. The emitting layer of [Alq: 0.7 Wt% rubrene possesses superior elecron-transporting ability.

13.
Nat Med ; 18(3): 385-7, 2012 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-22344297

RESUMO

For centuries, opioid drugs have been the mainstay of chronic pain treatment. However, over time analgesic tolerance develops, leaving few treatment options. Here we show that platelet-derived growth factor receptor-ß (PDGFR-ß)-mediated signaling plays a key role in morphine tolerance. PDGFR-ß inhibition selectively eliminates morphine tolerance in rats. PDGFR-ß inhibitors are widely used and well tolerated, suggesting that clinical translation of our findings could reduce the suffering endured by individuals with intractable pain.


Assuntos
Dor Crônica/tratamento farmacológico , Tolerância a Medicamentos/genética , Morfina/administração & dosagem , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptores Opioides mu/metabolismo , Ativação Transcricional/efeitos dos fármacos , Animais , Benzamidas , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Fentanila/farmacologia , Glioma/tratamento farmacológico , Mesilato de Imatinib , Morfina/efeitos adversos , Morfina/uso terapêutico , Fosforilação , Piperazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Ratos , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Receptores Opioides mu/agonistas
14.
J Proteome Res ; 7(11): 5040-8, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18841879

RESUMO

The effects of estradiol (E2) on the expression of proteins in the pars lateralis of the ventromedial nucleus of the hypothalamus (VMNpl) in ovariectomized rats was studied using 2-dimensional gel electrophoresis followed by RPLC-nanoESI-MS/MS. E2 treatment resulted in the up-regulation of 29 identified proteins. Many of these proteins are implicated in the promotion of neuronal plasticity and signaling.


Assuntos
Estradiol/farmacologia , Estrogênios/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas/metabolismo , Núcleo Hipotalâmico Ventromedial , Animais , Fenômenos Biológicos , Feminino , Ovariectomia , Proteômica/métodos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Núcleo Hipotalâmico Ventromedial/química , Núcleo Hipotalâmico Ventromedial/efeitos dos fármacos , Núcleo Hipotalâmico Ventromedial/metabolismo
15.
Brain Res Bull ; 76(5): 493-8, 2008 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-18534257

RESUMO

Decreases in serotonergic activity in the central nucleus of the amygdala reduce responses to stressors, suggesting an important role for serotonin in this region of the amygdala in stress reactivity. However, it is not known whether exposure to stressors actually increases serotonin release in the central nucleus of the amygdala. The current experiment tested the hypothesis that restraint stress increases extracellular serotonin within the central nucleus of the amygdala and adjacent medial amygdala using in vivo microdialysis in awake male rats during the dark phase of the light-dark cycle. Serotonin release in the central nucleus increased immediately in response to restraint stress. In contrast, there was no change in serotonin release within the adjacent medial amygdala during or following restraint. Since corticotropin-releasing factor is an important mediator of both responses to stressors and serotonergic activity, subsequent experiments tested the hypothesis that central nucleus serotonergic response to restraint stress is mediated by central corticotropin-releasing factor receptors. Administration of the corticotropin-releasing factor type 1 and 2 receptor antagonist d-Phe-CRF (icv, 10 microg/5 microl) prior to restraint stress suppressed restraint-induced serotonin release in the central nucleus. The results suggest that restraint stress rapidly and selectively increases serotonin release in the central nucleus of the amygdala by the activation of central corticotropin-releasing factor receptors. Furthermore, the results imply that corticotropin-releasing factor mediated serotonergic activity in central nucleus of the amygdala may be an important component of a stress response.


Assuntos
Tonsila do Cerebelo/metabolismo , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Restrição Física/efeitos adversos , Serotonina/metabolismo , Estresse Psicológico/metabolismo , Tonsila do Cerebelo/anatomia & histologia , Animais , Hormônio Liberador da Corticotropina/metabolismo , Masculino , Microdiálise , Ratos , Ratos Sprague-Dawley
16.
Ying Yong Sheng Tai Xue Bao ; 18(4): 853-8, 2007 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-17615884

RESUMO

A hydroponic study was conducted on the root growth, nutrient uptake, and root extracts and exudates of soybean and rice under aluminum (Al) stress. The results showed that low Al (10 micromol x L(-1)) stimulated the seed germination and root growth of soybean, but had no obvious promotion effects on rice. Al stress increased the P uptake, but decreased the K, Ca and Mg uptake by both soybean and rice. Rice accumulated less Al and more P than soybean. When exposed to Al stress, the soluble protein content in soybean and rice roots increased, soluble phenol decreased, while soluble sugar increased first and decreased then. The citrate content in soybean roots decreased obviously under Al stress. Compared with soybean, rice accumulated more soluble protein and phenol and less citrate, but no difference was observed in soluble sugar content. Al increased the exudation of citrate and soluble protein, phenol and sugar from soybean roots. Under Al stress, soybean roots possessed a higher cation exchange capacity than rice roots. It was suggested that soybean and rice had different physiological responses to Al stress. The Al tolerance of rice was probably associated with its higher P uptake and lower cation exchange capacity than soybean, while root exudates had no significant correlation with its Al tolerance.


Assuntos
Alumínio/toxicidade , Oryza/fisiologia , Germinação/fisiologia , Oryza/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/fisiologia , /metabolismo
17.
Proteomics ; 6(22): 6066-74, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17051637

RESUMO

The use of proteomics to study changes in the expression of CNS proteins, which may underlie the regulation of physiological and/or behavioral responses, represents an emerging application of this technology. In the current study, the Palkovits' microdissection method was evaluated as a means of obtaining proteomic data from discrete brain nuclei. The pars lateralis of the ventromedial nucleus of the hypothalamus (VMN) was chosen for the initial studies because of its established role in the expression of gonadal hormone dependent female sexual behavior. The VMN from ovariectomized rats was microdissected from 300 microm frozen brain sections using a 500 microm punch. Total proteins were separated using 2-DE. A group consensus of 432 protein spots, visualized by SYPRO Ruby stain, was obtained from gels from four independent VMN samples. A low mean CV and high gel-to-gel correlation coefficients indicate that reproducible 2-DE gels can be generated from microdissected tissue samples. Proteins from the mediobasal hypothalamus (MBH) were also separated on 2-DE gels. Evaluation of the 2-DE maps from the VMN and the MBH revealed different protein profiles, and indicates that microdissection improves the detection of low-abundance proteins, and reduces the relative occurrence of abundant proteins on 2-DE maps.


Assuntos
Proteômica/métodos , Núcleo Hipotalâmico Ventromedial/metabolismo , Animais , Eletroforese em Gel Bidimensional/métodos , Feminino , Espectrometria de Massas/métodos , Polienos/metabolismo , Ratos , Ratos Sprague-Dawley
18.
Brain Res ; 1063(1): 69-76, 2005 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-16266691

RESUMO

In the rat dorsomedial hypothalamus (DMH), serotonin (5-HT) concentrations are altered rapidly in response to acute stressors. The mechanism for rapid changes in 5-HT concentrations in the DMH is not clear. We hypothesize that the mechanism involves corticosteroid-induced alterations in the uptake of 5-HT from extracellular fluid through the action of corticosterone-sensitive organic cation transporters (OCTs). To determine if OCTs affect the clearance of 5-HT from the extracellular fluid compartment within the medial hypothalamus (MH), the OCT blocker, decynium 22 (0, 10, 30, or 100 microM), was perfused into the MH via a microdialysis probe, and dialysate 5-HT concentrations were measured at 20 min intervals. In addition, home cage behavior was measured both before and after drug administration. Inhibition of OCTs in the MH resulted in a reversible dose-dependent increase in extracellular 5-HT concentration. Increases in extracellular 5-HT concentrations were associated with increases in grooming behavior in rats treated with the highest concentration of decynium 22. No other behavioral responses were observed following administration of any concentration of decynium 22. These findings are consistent with the hypothesis that OCTs in the MH play an important role in the regulation of serotonergic neurotransmission and specific behavioral responses. Because the MH plays an important role in the neuroendocrine, autonomic, and behavioral responses to stress-related stimuli, these data lead to new questions regarding the role of interactions between corticosterone and corticosterone-sensitive OCTs in stress-induced 5-HT accumulation within the MH as well as the physiological and behavioral consequences of these interactions.


Assuntos
Asseio Animal/efeitos dos fármacos , Hipotálamo Médio/metabolismo , Proteínas de Transporte de Cátions Orgânicos/fisiologia , Serotonina/metabolismo , Análise de Variância , Animais , Relação Dose-Resposta a Droga , Líquido Extracelular/química , Asseio Animal/fisiologia , Hipotálamo Médio/efeitos dos fármacos , Masculino , Microdiálise , Proteínas de Transporte de Cátions Orgânicos/antagonistas & inibidores , Quinolinas/administração & dosagem , Ratos , Ratos Wistar , Serotonina/análise , Estatísticas não Paramétricas
19.
Virology ; 305(2): 267-75, 2003 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-12573572

RESUMO

We surveyed influenza activity in a live poultry market in Central China for 16 months, isolating viruses from 1% of 6360 fecal samples. We obtained multiple H3N6, H9N2, H2N9, H3N3, and H4N6 isolates and single H1N1 and H3N2 isolates. Two distinct H3 molecules were identified; other hemagglutinin subtypes were phylogenetically homogeneous. The H3N6 viruses (9 genotypes) and H9N2 viruses (4 genotypes) were genetically heterogeneous, whereas the H2N9, H3N3 and H4N6 viruses had single genotypes. Thirteen representative viruses were tested for their ability to replicate in quail and chickens. All tested viruses replicated in the respiratory tract of quail. Only nine of the viruses were shed in detectable levels in infected chickens, and four of these were detected in less than 50% of infected birds. A single H4N6 isolate caused disease and systemic spread in chickens. These findings show that quail are broadly susceptible to different subtypes of influenza A virus.


Assuntos
Pool Gênico , Vírus da Influenza A/genética , Aves Domésticas/virologia , Animais , Galinhas/virologia , China , Columbidae/virologia , Vírus da Influenza A/classificação , Vírus da Influenza A/fisiologia , Codorniz/virologia , Replicação Viral
20.
Di Yi Jun Yi Da Xue Xue Bao ; 21(11): 858-859, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-12426193

RESUMO

OBJECTIVE: To investigate the clinical significance of detecting interleukin-6 (IL-6) and interleukin-12 (IL-12) in the immunological mechanism of hepatitis B virus infection (HBV). METHODS: Serum IL-6 and IL-12 levels were determined using enzyme-linked immunosorbent assay in patients with chronic, acute or advanced hepatitis B as well as in healthy subjects. RESULTS: In chronic, acute, severe hepatitis B patients, serum IL-6 levels were significantly elevated as hepatitis worsened (199.7+/-26.9, 129.5+/-22.8, 286.1+/-56.7 pg/ml respectively), in that order compared with the normal control levels (56.41+/-12.9 pg/ml). IL-12 levels, in contrast, tended to be lowered with the deterioration of hepatitis (24.6+/-13.4, 135.3+/-60.8, 19.7+/-9.0 pg/ml respectively), in that order, with the control level of 34.7+/-11.8 pg/ml. CONCLUSION: Serum IL-6 level is closely correlated to the degree of hepatocyte damage in hepatitis B, while IL-12 may be instrumental in the defense mechanism against HBV infection, and IL-12 level elevation can be indicative of hepatitis recovery.

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