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1.
Molecules ; 25(2)2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31936531

RESUMO

Among the popular electrochemical energy storage devices, supercapacitors (SCs) have attracted much attention due to their long cycle life, fast charge and discharge, safety, and reliability. Transition metal oxides are one of the most widely used electrode materials in SCs because of the high specific capacitance. Among various transition metal oxides, Co3O4 and related composites are widely reported in SCs electrodes. In this review, we introduce the synthetic methods of Co3O4, including the hydrothermal/solvothermal method, sol-gel method, thermal decomposition, chemical precipitation, electrodeposition, chemical bath deposition, and the template method. The recent progress of Co3O4-containing electrode materials is summarized in detail, involving Co3O4/carbon, Co3O4/conducting polymer, and Co3O4/metal compound composites. Finally, the current challenges and outlook of Co3O4 and Co3O4-containing composites are put forward.

2.
Phys Chem Chem Phys ; 21(42): 23697-23704, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31633133

RESUMO

The desolvation effect of ions plays an important role in adjusting the capacity of supercapacitors and has attracted considerable attention after its discovery. Here, first-principles calculations were conducted to calculate the reaction energies of ions, water, and hydrated ions in bilayer graphene (BG) with different interlayer spacings (d) and to explore the desolvation behaviors of H+, Li+, Na+, and K+ ions. The calculated results showed that H+ can only exist in the state of H3O+ in AA-stacking BG, and desolvation exists only in the case of AB-stacking BG. The complete desolvation size for H+ ions in the AB-stacking system reached 5.6 Å, which was the largest desolvation size of the four ions studied. The critical desolvation sizes of Li+, Na+, and K+ in the BG layers of AA- and AB-stacking increased sharply as a consequence of the increasing ionic radius. However, the complete desolvation sizes of all three ions were in the range of 4-5 Å and with the increase in ionic radius, the complete desolvation sizes showed a reverse tendency. The complete desolvation size of Na+ in AB-stacking BG was slightly larger than that in AA-stacking BG. Further analysis presented that the ionic radii of H+, Li+, Na+, and K+ ions make a dominant contribution to the critical size of desolvation. Our present results provide useful information for improving the capacity of supercapacitors by precisely matching the pore structure and electrolyte through the adjustment of the pore structure of carbon materials.

3.
Materials (Basel) ; 12(9)2019 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-31060284

RESUMO

Electrode materials are crucial for the electrochemical performance of supercapacitors. In view of the high specific surface area, high conductivity of graphene nanosheets and the high pseudocapacitance of polyaniline (PANI), the combination of graphene with PANI has become a research hotspot. In this work, we summarize the recent advance on the synthesis of PANI and graphene/PANI composites, and their application in supercapacitors. The synthesis of PANI is the basis of preparing graphene/PANI composites, so we first introduce the synthesis methods of PANI. Then, the advances of two dimensional (2D) and three dimensional (3D) graphene/PANI composites are summarized according to the inherent feature of graphene. The 2D composites of pristine graphene and functionalized graphene with PANI are introduced separately; furthermore, the 3D composites are classified into three sections, including flexible graphene/PANI composites, graphene framework based composites, and printable graphene/PANI composites. At last, aiming at solving the current challenges of graphene/PANI composites, we put forward some strategies for preparing high performance graphene/PANI composite electrodes.

4.
Behav Brain Res ; 364: 62-74, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-30753874

RESUMO

Neuronostatin (NST) is composed of a 13-amino acid and amidated peptide hormone encoded in the somatostatin (SST) gene, and plays an important physiological function in diverse tissues. Previous studies have shown that intracerebroventricular (i.c.v.) and intra-hippocampally administration of NST can significantly decrease the percentage of novel object exploration time in the step-down test. In this study, to define the contribution of NST to cognitive impairments induced by soluble Aß42 oligomers (oAß), along with the underlying mechanisms. This study used behavioral, biochemical and immunohistological methods to find that i.c.v. administration of NST (3 nmol/mouse) disrupted the ability of spatial learning and memory in mice, led to increase the levels of cAMP, GPR107 protein expression and phosphorylation of PKA at Thr197 in the cortex and hippocampus. NST promoted oAß (1 nmol/mouse) -induced cognitive impairments, subsequently co-injection of NST and oAß increased the levels of GPR107 expression and PKA phosphorylation, which also led to hyperactivation of GFAP in the cortex and neuroinflammation cytokines (IL-1ß, IL-6 and TNFα) both in the cortex and hippocampus. Moreover, it was demonstrated that co-administration of NST and oAß had increased the phosphorylation of Akt and GSK3ß and reduced the levels of ATP and hexokinase (HK) activity in the cortex. Therefore, taken together, this study provided powerful insight into the mechanism of NST for memory impairments induced by oAß, and may potentially serve as a promising target for future Alzheimer's disease interventions.

5.
Oral Dis ; 25(4): 1175-1184, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30811745

RESUMO

OBJECTIVE: The aim of this study was to investigate the effects of epigallocatechin-3-gallate on the proliferation and apoptosis of odontogenic keratocyst (OKC) keratinocytes in vitro. MATERIALS AND METHODS: Keratinocytes isolated from the epithelial lining of the OKC were cultured in keratinocyte serum-free medium and identified by CK10, CK14, pan-cytokeratin and vimentin immunofluorescence staining. The cells were exposed to EGCG at different concentrations, and proliferation inhibition was measured by cell counting kit 8 assay. Cell cycle and apoptosis were assessed by flow cytometry, and expression of the WNT signalling pathway-related proteins FZD3 and JNK3 was detected by quantitative real-time PCR and Western blotting. Human oral keratinocytes (HOKs) were used as the control. RESULTS: The OKC keratinocytes were successfully cultured. The primary cells were tile-like and expressed the epithelial biomarkers CK10, CK14 and pan-cytokeratin. Epigallocatechin-3-gallate inhibited cell proliferation in a dose- and time-dependent manner, arrested cell cycle in the G1 phase and induced apoptosis of OKC keratinocytes. FZD3 and JNK3 were overexpressed in OKC keratinocytes compared with HOKs and were downregulated by epigallocatechin-3-gallate treatment. CONCLUSION: Epigallocatechin-3-gallate inhibited proliferation and induced apoptosis in OKC keratinocytes, possibly by suppressing the WNT/JNK signalling pathway. It may thus be potentially used for OKC treatment.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Catequina/análogos & derivados , Proliferação de Células/efeitos dos fármacos , Catequina/farmacologia , Humanos , Queratinócitos , Sistema de Sinalização das MAP Quinases , Cistos Odontogênicos , Via de Sinalização Wnt
6.
Phys Chem Chem Phys ; 19(48): 32708-32714, 2017 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-29199287

RESUMO

Lithium-sulfur (Li-S) batteries have attracted increasing attention due to their high theoretical capacity, being a promising candidate for portable electronics, electric vehicles and large-scale energy storage. The interactions of bilayer structured graphitic C3N4 (bi-C3N4) with S8, lithium polysulfides (LiPSs), 1,3-dioxolane, 1,2-dimethoxyethane and tetrahydrofuran ether-based solvents have been studied using first-principles calculations. It has been found that the (micropore-scale) interlayer of bi-C3N4 shows intimate contact and strong binding with S8 and LiPSs due to the formation of chemical Li-N bonds. The incorporation of soluble LiPSs by the wrinkled layers of bi-C3N4 with 5.5-7.2 Å interlayer pores can suppress the shuttling effect. The interlayer ultramicropores with interlayer distances of <4 Å can accommodate the small Li2S2 and Li2S molecules, and impede the irreversible reaction between the solvents and the LiPSs. The calculated energy gap of bi-C3N4 decreases to be narrow during lithiation. Our results can provide a guideline for promoting the electrochemical performance of microporous g-C3N4/sulfur composites for Li-S batteries.

7.
Front Aging Neurosci ; 9: 435, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29358916

RESUMO

The Akt kinase has been widely assumed for years as a key downstream effector of the PI3K signaling pathway in promoting neuronal survival. This notion was however challenged by the finding that neuronal survival responses were still preserved in mice with reduced Akt activity. Moreover, here we show that the Akt signaling is elevated in the aged brain of two different mice models of Alzheimer Disease. We manipulate the rate of Akt stimulation by employing knock-in mice expressing a mutant form of PDK1 (phosphoinositide-dependent protein kinase 1) with reduced, but not abolished, ability to activate Akt. We found increased membrane localization and activity of the TACE/ADAM17 α-secretase in the brain of the PDK1 mutant mice with concomitant TNFR1 processing, which provided neurons with resistance against TNFα-induced neurotoxicity. Opposite to the Alzheimer Disease transgenic mice, the PDK1 knock-in mice exhibited an age-dependent attenuation of the unfolding protein response, which protected the mutant neurons against endoplasmic reticulum stressors. Moreover, these two mechanisms cooperatively provide the mutant neurons with resistance against amyloid-beta oligomers, and might singularly also contribute to protect these mice against amyloid-beta pathology.

8.
Mol Cell Biol ; 36(23): 2967-2982, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27644329

RESUMO

The phosphoinositide (PI) 3-kinase/Akt signaling pathway plays essential roles during neuronal development. 3-Phosphoinositide-dependent protein kinase 1 (PDK1) coordinates the PI 3-kinase signals by activating 23 kinases of the AGC family, including Akt. Phosphorylation of a conserved docking site in the substrate is a requisite for PDK1 to recognize, phosphorylate, and activate most of these kinases, with the exception of Akt. We exploited this differential mechanism of regulation by generating neuron-specific conditional knock-in mice expressing a mutant form of PDK1, L155E, in which the substrate-docking site binding motif, termed the PIF pocket, was disrupted. As a consequence, activation of all the PDK1 substrates tested except Akt was abolished. The mice exhibited microcephaly, altered cortical layering, and reduced circuitry, leading to cognitive deficits and exacerbated disruptive behavior combined with diminished motivation. The abnormal patterning of the adult brain arises from the reduced ability of the embryonic neurons to polarize and extend their axons, highlighting the essential roles that the PDK1 signaling beyond Akt plays in mediating the neuronal responses that regulate brain development.

9.
Tumour Biol ; 37(5): 6477-83, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26631045

RESUMO

MicroRNAs (miRNAs) play several important roles in carcinogenesis, and the dysregulation of miRNAs is associated with cancer progression. Little is known about the role of miR-613 in ovarian cancer. In the present study, we demonstrate that miR-613 expression is downregulated in human ovarian cancer cell lines and tissues. Additionally, miR-613 overexpression suppressed ovarian cancer cell proliferation, colony formation, and invasion. Furthermore, KRAS was identified as a target of miR-613. Reintroducing KRAS rescued the inhibitory effects exerted by miR-613 on ovarian cancer cell proliferation and invasion. Taken together, our findings suggest that miR-613 functions as a candidate tumor suppressor miRNA in ovarian cancer by directly targeting KRAS. To the best of our knowledge, this is the first study to show that miR-613 affects the proliferation and invasion of ovarian cancer.


Assuntos
MicroRNAs/genética , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Regiões 3' não Traduzidas , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Interferência de RNA
10.
Chem Biol Interact ; 227: 37-44, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25559852

RESUMO

We attempted to determine whether betanin (from natural pigments) that has antioxidant properties would be protective against fructose-induced diabetic cardiac fibrosis in Sprague-Dawley rats. Fructose water solution (30%) was accessed freely, and betanin (25 and 100 mg/kg/d) was administered by intra-gastric gavage continuously for 60 d. Rats were sacrificed after overnight fast. The rat blood and left ventricle were collected. In vitro antiglycation assay in bovine serum albumin/fructose system was also performed. In rats treated only with fructose, levels of plasma markers: glucose, insulin, HOMA and glycated hemoglobin rised, left ventricle collagen accumulated and cross-linked, profibrotic factor-transforming growth factor (TGF)-ß1 and connective tissue growth factor (CTGF) protein expression increased, and soluble collagen decreased, compared with those in normal rats, showing fructose induces diabetic cardiac fibrosis. Treatment with betanin antagonized the changes of these parameters, demonstrating the antifibrotic role of betanin in the selected diabetic models. In further mechanistic study, betanin decreased protein glycation indicated by the decreased levels of protein glycation reactive intermediate (methylglyoxal), advanced glycation end product (N(ε)-(carboxymethyl) lysine) and receptors for advanced glycation end products (AGEs), antagonized oxidative stress and nuclear factor-κB activation elicited by fructose feeding, suggesting inhibition of glycation, oxidative stress and nuclear factor-κB activation may be involved in the antifibrotic mechanisms. Betanin also showed anitglycative effect in BSA/fructose system, which supported that anitglycation was involved in betanin's protective roles in vivo. Taken together, the potential for using betanin as an auxillary therapy for diabetic cardiomyopathy deserves to be explored further.


Assuntos
Betacianinas/farmacologia , Colágeno/metabolismo , Coração/efeitos dos fármacos , Miocárdio/metabolismo , Animais , Glicemia/análise , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Fibrose/metabolismo , Fibrose/patologia , Frutose/farmacologia , Hemoglobina A Glicada/análise , Produtos Finais de Glicação Avançada/sangue , Glicosilação/efeitos dos fármacos , Insulina/sangue , Lisina/análogos & derivados , Lisina/análise , Masculino , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Fator de Crescimento Transformador beta1/metabolismo
11.
Int J Mol Sci ; 16(1): 363-77, 2014 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-25548895

RESUMO

KAP1 is an universal corepressor for Kruppel-associated box zinc finger proteins in both normal and tumor cells. In this study, the biological function and clinical significance of KAP1 expression in ovarian cancer were investigated. Immunohistological staining of KAP1 was evaluated in 111 patients with ovarian epithelial cancer, 15 with ovarian borderline tumor, and 20 normal ovarian tissue. The correlations of KAP1 expression with clinicopathological features were studied. Kaplan-Meier analysis and Cox proportional hazard modeling were used to assess overall survival to analyze the effect of KAP1 expression on the prognosis of ovarian cancer. The positive rates of KAP1 were significantly higher in ovarian epithelial cancer (55.7%) and borderline tumor (20.0%) than in normal ovarian tissue (5.0%) (all p < 0.01). KAP1 expression correlated significantly with clinical stage (χ2 = 14.57, p < 0.0001), pathological grade (χ2 = 6.06, p = 0.048) and metastases (χ2 =10.38, p = 0.001). Patients with high KAP 1 levels showed poor survival (p < 0.0001). Multivariate analysis showed that KAP1 high expression was an independent predictor for ovarian cancer patients (hazard ratio = 0.463; 95% confidence interval = 0.230-0.9318, p = 0.031). Functionally, depletion of KAP1 by siRNA inhibited ovarian cancer cell proliferation, cell migration. KAP1 expression correlated with aggressive clinical features in ovarian cancer. High KAP1 expression was a prognostic factor of ovarian cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma/metabolismo , Neoplasias Ovarianas/metabolismo , Proteínas Repressoras/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Carcinoma/diagnóstico , Estudos de Casos e Controles , Linhagem Celular Tumoral , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/diagnóstico , Proteínas Repressoras/genética , Proteína 28 com Motivo Tripartido
12.
Wei Sheng Wu Xue Bao ; 54(6): 624-34, 2014 Jun 04.
Artigo em Chinês | MEDLINE | ID: mdl-25272810

RESUMO

OBJECTIVE: To screen new agro-antibiotics, rare actinomycetes were isolated by improved separation methods from soil samples and the chemical structure of the antifungal active product was elucidated. METHODS: Dry heating method was used for soil samples pretreatment and the improved HV separation medium for rare actinomycetes separation; agar block rapid screening was used for the rapid evaluation of rare actinomycetes biological activity. For the identification of a strain numbered TJ430, morphology observation, cell chemical composition analysis, physiological and biochemical analysis, enzymology characteristics analysis, 16 S rDNA sequence analysis, and DNA hybridization method were used. Bioactive crude extract from fermentation was purified by column chromatography and preparative chromatography; infrared spectroscopy and high resolution mass spectrometry was used for structure elucidation of bioactive ingredient. RESULTS: A total of 570 rare actinomycetes strains were isolated. Antibacterial activity of rapid screen showed that the numbed TJ430 strain showed excellent anti oomycetes and broad-spectrum antifungal activity. Strain identification results show that the strain is a S. cavourensis. The molecular formulas of the effective ingredient is C40H66N3O11, molecular weight is 765. Amino, methyl, methylene, carbonyl, covalent bond, isopropyl and other chemical groups should contained in the molecular. CONCLUSION: The characterized antibacterial active ingredient has good development prospect.


Assuntos
Antifúngicos/farmacologia , Microbiologia do Solo , Streptomyces/química , Streptomyces/metabolismo , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/metabolismo , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Filogenia , Streptomyces/genética , Streptomyces/isolamento & purificação
13.
Food Chem Toxicol ; 70: 100-6, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24799198

RESUMO

We attempted to determine whether betanin (from natural pigments) that has anti-oxidant properties would be protective against paraquat-induced liver injury in Sprague-Dawley rats. Paraquat was injected intraperitoneally into rats to induce liver toxicity. The rats were randomly divided into four groups: a control group, a paraquat group, and two groups that received betanin at doses of 25 and 100mg/kg/day three days before and two days after they were administered paraquat. We evaluated liver histopathology, serum liver enzymatic activities, oxidative stress, cytochrome P450 (CYP) 3A2 mRNA expression, and mitochondrial damage. The rats that were injected with paraquat incurred liver injury, evidenced by histological changes and elevated serum aspartate aminotransferase and alanine aminotransferase levels; paraquat also led to oxidative stress, an increase of cytochrome P450 3A2 mRNA expression, and mitochondrial damage, indicated by mitochondrial membrane swelling, reduced mitochondrial cytochrome C, and apoptosis-inducing factor protein levels. Pathological damage and all of the above mentioned markers were lesser in the animals treated with betanin than in those who received paraquat alone. Betanin had a protective effect against paraquat-induced liver damage in rats. The mechanism of the protection appears to be the inhibition of CYP 3A2 expression and protection of mitochondria.


Assuntos
Betacianinas/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Fígado/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Paraquat/toxicidade , Animais , Antioxidantes/administração & dosagem , Fator de Indução de Apoptose/metabolismo , Biomarcadores/sangue , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Citocromos c/metabolismo , Fígado/metabolismo , Masculino , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
14.
Fish Physiol Biochem ; 40(3): 865-74, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24271879

RESUMO

This study investigates the protective effect of betanin against liver injury induced by carbon tetrachloride (CCl4) in common carp (Cyprinus carpio L.). The fish were treated with 1, 2, and 4 % betanin in fodder throughout the experiment. After 20 days of treatment, the fish were intraperitoneally injected with 20 % (v/v in peanut oil) CCl4 at a volume of 0.5 mL/kg body weight. The fish were killed 3 days after CCl4 intoxication, and then, histological and biochemical assays were performed. Results showed that CCl4-induced liver CYP2E1 activity, oxidative stress, and injury, as indicated by the depleted glycogen storage, increased serum aspartate aminotransferase (AST)/alanine aminotransferase (ALT) activities and liver histological damage. Compared with the CCl4 control group, the betanin-treated groups exhibited reduced CYP2E1 activity, decreased malondialdehyde level, increased liver antioxidative capacity (increased glutathione level and superoxide dismutase and catalase activities), increased liver glycogen storage, and reduced serum AST/ALT activities, with significant differences in the 2 and 4 % groups (p < 0.05). Histological assay further confirmed the protective effect of betanin. In conclusion, betanin attenuates CCl4-induced liver damage in common carp. Moreover, the inhibition of CYP2E1 activity and oxidative stress may have significant roles in the protective effect of betanin.


Assuntos
Betacianinas/uso terapêutico , Intoxicação por Tetracloreto de Carbono/prevenção & controle , Carpas , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Intoxicação por Tetracloreto de Carbono/patologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Citocromo P-450 CYP2E1/metabolismo , Glicogênio/metabolismo , Fígado/enzimologia , Fígado/patologia , Estresse Oxidativo , Distribuição Aleatória
15.
Bull Environ Contam Toxicol ; 92(2): 196-201, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24326676

RESUMO

The widely used antibiotic metronidazole (MTZ) was investigated for its toxic effects on the innate immunity in common carp (Cyprinus carpio L.). The fish were exposed to MTZ at nominal concentrations of 0.1, 0.5, and 2.5 mg L(-1) in water for 30 days, followed by a 5-days of cleanout period, after which certain innate immunity parameters were measured. The results showed that under the tested concentrations, MTZ-exposed fish exhibited decline in several humoral and cellular parameters, including complement activity, lysozyme activity, bactericidal activity, total serum protein levels, total WBC count, and the respiratory burst activity of kidney leukocytes. Except for total serum proteins, all of these parameters showed a significant difference in the 2.5 mg L(-1) MTZ group compared to control group (p < 0.05). The results clearly support the contention that MTZ suppresses the innate immunity of common carp.


Assuntos
Anti-Infecciosos/toxicidade , Carpas/imunologia , Imunidade Inata/efeitos dos fármacos , Metronidazol/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Carpas/fisiologia , Rim/citologia , Rim/efeitos dos fármacos , Testes de Toxicidade
16.
J Mol Model ; 19(12): 5579-86, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24257902

RESUMO

The geometrical structures, energetics properties, and aromaticity of C(36-n) Si(n) (n ≤ 18) fullerene-based clusters were studied using density functional theory calculations. The geometries of C(36-n) Si(n) clusters undergo strong structural deformation with the increase of Si substitution. For the most energy favorable structures of C(36-n) Si(n) , the silicon and carbon atoms form two distinct homogeneous segregations. Subsequently, the binding energy, HOMO-LUMO energy gap, vertical ionization potential, vertical electron affinity, and chemical hardness for the energetic favorable C(36-n) Si(n) geometries were computed and analyzed. In addition, the aromatic property of C(36-n) Si(n) cagelike clusters was investigated, and the result demonstrate that these C(36-n) Si(n) cagelike structures possess strong aromaticity.

17.
Peptides ; 44: 105-10, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23548325

RESUMO

Neuronostatin, a 13-amino acid peptide, is encoded in the somatostatin pro-hormone. I.c.v. administration of neuronostatin produces a significant antinociceptive effect in the mouse tail-flick test, which is mediated by endogenous opioid receptor. However, the direct functional interaction between morphine and neuronostatin has not been characterized. In the present study, effect of neuronostatin on morphine analgesia was investigated in the tail-flick test. Our findings showed that i.c.v. administration of neuronostatin (0.3nmol/mouse i.c.v.) significantly enhanced the antinociceptive effect of morphine (2.5, 5 or 10µg/kg) at the supraspinal level. Results of antagonism experiments suggested that the synergistic analgesia induced by morphine and neuronostatin was mediated by µ- and к-opioid receptors not δ-opioid receptor. In conclusion, there may be a cascade amplification phenomenon when morphine and neuronostatin were co-administered in acute pain model. The above results provide evidence for the potential use of neuronostatin in combination with morphine to control pain and addiction.


Assuntos
Analgésicos Opioides/farmacologia , Morfina/farmacologia , Fragmentos de Peptídeos/farmacologia , Somatostatina/farmacologia , Analgesia , Animais , Sinergismo Farmacológico , Injeções Intraventriculares , Masculino , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Nociceptividade/efeitos dos fármacos , Fragmentos de Peptídeos/fisiologia , Receptores Opioides/metabolismo , Somatostatina/fisiologia
18.
J Exp Zool A Ecol Genet Physiol ; 319(3): 117-23, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23319459

RESUMO

Phrynocephalus vlangalii is a species of lizard endemic in China, which lives on Qinghai-Tibet Plateau ranging from 2000 to 4600 m above sea level. In this study, P. vlangalii were collected from low altitude (2750 m) and high altitude (4564 m). The lizards from low altitude were acclimatized in simulated hypoxic chamber (equivalent to 4600 m) for 7, 15, and 30 days. The hematological parameters, heart weight, myocardial capillary density, and myocardial enzyme activities were examined. The results showed that acclimatization to hypoxia significantly increased hemoglobin concentration ([Hb]), hematocrit (Hct), heart weight (HW), heart weight to body mass (HW/BM), lactate dehydrogenase (LDH) activity, but markedly decreased mean corpuscular hemoglobin concentration (MCHC) and succinate dehydrogenase (SDH) activity. Red blood cell (RBC) count, body mass (BM), myocardial capillary density did not change markedly during hypoxic acclimatization. On the other hand, [Hb], Hct, MCHC, HW/BM, myocardium capillary density, and SDH activity of P. vlangalii from high altitude were remarkably higher than those from low-altitude; however, LDH activity of high-altitude P. vlangalii was lower than that of low-altitude lizards. There was no significant difference in HW or BM between populations of high-altitude and low-altitude. Based on the present data, we suggest that P. vlangalii has special anatomical, physiological, and biochemical accommodate mechanisms to live in hypoxic environment, and the regulative mechanisms are different between hypoxic acclimatization and adaptation.


Assuntos
Aclimatação/fisiologia , Adaptação Fisiológica , Lagartos/fisiologia , Altitude , Animais , China , Contagem de Eritrócitos , Hematócrito , Hipóxia/sangue , Tibet
19.
Peptides ; 35(1): 31-5, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22465660

RESUMO

Neuronostatin is a 13-amino acid amidated peptide widely distributed in various organs including gastrointestinal tract. However, the effect of neuronostatin on gastrointestinal motility has not been well characterized. In the present work, effects of central administration of neuronostatin on gastric emptying and gastrointestinal transit were investigated. The results indicated that intracerebroventricular (i.c.v.) administration of neuronostatin (1, 5, 10 or 20nmol/mouse) delayed gastric emptying and gastrointestinal transit in a dose-related manner in mice. The effects were significantly reversed by melanocortin 3/4 receptor antagonist SHU9119 or classical opioid receptor antagonist naloxone, suggesting that the central melanocortin system and opioid system may be involved in the gastrointestinal effects elicited by i.c.v. administration of neuronostatin. In addition, we found that C-terminal amidation modification of neuronostatin is essential to exert its gastrointestinal effects. These results indicated that neuronostatin may play an important role in regulating gastrointestinal function.


Assuntos
Ventrículos Cerebrais/fisiologia , Esvaziamento Gástrico , Trânsito Gastrointestinal , Hormônios Peptídicos/fisiologia , Animais , Ventrículos Cerebrais/efeitos dos fármacos , Ventrículos Cerebrais/metabolismo , Esvaziamento Gástrico/efeitos dos fármacos , Trânsito Gastrointestinal/efeitos dos fármacos , Masculino , Hormônios Estimuladores de Melanócitos/farmacologia , Camundongos , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Hormônios Peptídicos/administração & dosagem , Receptores de Melanocortina/agonistas
20.
Neurosci Lett ; 506(1): 126-30, 2012 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-22075225

RESUMO

Neuronostatin, a newly identified peptide encoded by the somatostatin (SST) gene, was proved to produce significant antinociceptive effect in mouse tail immersion test. However, the effect of neuronostatin on tonic pain was still not clear. The aim of this study was to investigate the effect of neuronostatin in the formalin test and its possible mechanism. We found that intracerebroventricular (i.c.v.) administration of neuronostatin (1, 3, 6, 12nmol/mouse) increased licking in a dose-related manner during the late phase, but did not affect the early phase of formalin test in mice. In addition, the hyperalgesic effect during the late phase was completely reversed by melanocortin 3/4 receptor antagonist SHU9119 (50pmol/mouse) or opioid receptor antagonist naloxone (5nmol/mouse), but not GABAA receptor antagonist bicuculline (1086pmol/mouse). These data suggested that the hyperalgesic response induced by neuronostatin was dependent upon the central melanocortin system and endogenous opioid system. In conclusion, these results indicated that neuronostatin may be a new neuropeptide with important role in the modulation of acute and tonic pain.


Assuntos
Hiperalgesia/induzido quimicamente , Hiperalgesia/tratamento farmacológico , Medição da Dor , Limiar da Dor/efeitos dos fármacos , Fragmentos de Peptídeos/efeitos adversos , Somatostatina/efeitos adversos , Análise de Variância , Animais , Bicuculina/uso terapêutico , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Interações de Medicamentos , Antagonistas de Receptores de GABA-A/uso terapêutico , Injeções Intraventriculares , Masculino , Hormônios Estimuladores de Melanócitos/uso terapêutico , Camundongos , Camundongos Endogâmicos , Fatores de Tempo
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