Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
1.
Anesthesiology ; 127(3): 548-564, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28582325

RESUMO

BACKGROUND: The authors previously reported that noncoding microRNA miR-219-5p is down-regulated in the spinal cord in a nociceptive state. The ventral tegmental area also plays critical roles in modulating nociception, although the underlying mechanism remains unknown. The authors hypothesized that miR-219-5p in the ventral tegmental area also may modulate nociception. METHODS: The authors studied the bidirectional regulatory role of ventral tegmental area miR-219-5p in a rat complete Freund's adjuvant model of inflammatory nociception by measuring paw withdrawal latencies. Using molecular biology technologies, the authors measured the effects of astroglial coiled-coil and C2 domain containing 1A/nuclear factor κB cascade and dopamine neuron activity on the down-regulation of ventral tegmental area miR-219-5p-induced nociceptive responses. RESULTS: MiR-219-5p expression in the ventral tegmental area was reduced in rats with thermal hyperalgesia. Viral overexpression of ventral tegmental area miR-219-5p attenuated complete Freund's adjuvant-induced nociception from 7 days after complete Freund's adjuvant injection (paw withdrawal latencies: 6.09 ± 0.83 s vs. 3.96 ± 0.76 s; n = 6/group). Down-regulation of ventral tegmental area miR-219-5p in naïve rats was sufficient to induce thermal hyperalgesia from 7 days after lentivirus injection (paw withdrawal latencies: 7.09 ± 1.54 s vs. 11.75 ± 2.15 s; n = 8/group), which was accompanied by increased glial fibrillary acidic protein (fold change: 2.81 ± 0.38; n = 3/group) and reversed by intraventral tegmental area injection of the astroglial inhibitor fluorocitrate. The nociceptive responses induced by astroglial miR-219-5p down-regulation were inhibited by interfering with astroglial coiled-coil and C2 domain containing 1A/nuclear factor-κB signaling. Finally, pharmacologic inhibition of ventral tegmental area dopamine neurons alleviated this hyperalgesia. CONCLUSIONS: Down-regulation of astroglial miR-219-5p in ventral tegmental area induced nociceptive responses are mediated by astroglial coiled-coil and C2 domain containing 1A/nuclear factor-κB signaling and elevated dopamine neuron activity.


Assuntos
Astrócitos/metabolismo , Hiperalgesia/fisiopatologia , MicroRNAs/metabolismo , Nociceptividade/fisiologia , Área Tegmentar Ventral/metabolismo , Animais , Modelos Animais de Doenças , Regulação para Baixo/fisiologia , Masculino , Ratos , Ratos Wistar , Transdução de Sinais/fisiologia
2.
Dalton Trans ; 51(9): 3502-3511, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35142313

RESUMO

Carbon dioxide (CO2) and the combustion of sulfide in gasoline are the main causes of air pollution. A great deal of attention has been paid to solving the problem and the catalytic reaction seems to be a decent choice. Due to the high-density of Lewis acidic active sites, polyoxometalates are undoubtedly an ideal choice for the sulfur oxidation reaction. With the reasons foregoing, two novel Zn-capped polyoxometalate-based organic-inorganic hybrids, {[α-PMoV2MoVI10O39(OH)Zn2][bbbm]3}·0.5C2H5OH (1) and TBA2{[ε-PMoV8MoVI4O37(OH)3Zn4][phim]3} (2) ((where bbbm = 1-(4-imidazol-1-ylbutyl) imidazole) and phim = 2-phenylimidazole) were successfully obtained by hydrothermal synthesis. In the two compounds, the N-donor ligands in a monodentate or bidentate coordination mode are directly connected to the Keggin anions by Zn-capped atoms, forming an extended one-dimensional chain. It is noteworthy that compound 2 ends up with an interesting spiral infinite chain possibly thanks to the TBA+ cations residing in gaps as structure-directing agents. Simultaneously, the catalytic properties indicate that compounds 1 and2 as efficient heterogeneous catalysts display a decent catalytic activity in the sulfur removal process. Especially, 2 enabled satisfying catalytic oxidation of dibenzothiophene (DBT) to produce more valuable dibenzothiophene sulfone (DBTO2) at 55 °C, and the conversion almost reached 99%. Besides, compound 2 also shows satisfactory catalytic effectiveness in the oxidation of various epoxides in the CO2 cycloaddition reaction, which suggests that compound 2 has the potential to function as a dual functional material with tremendous prospects in sulfur oxidation and carbon dioxide cycloaddition for the first time.

3.
Dalton Trans ; 50(39): 13925-13931, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34528636

RESUMO

Designing and synthesizing lanthanide clusters have always been a research hotspot. Herein, three lanthanide clusters with the formula [Ln8(IN)14(µ3-OH)8(µ2-OH)2(H2O)8]·xH2O (Ln = 1-Gd and x = 11; Ln = 2-Dy and x = 8; Ln = 3-Eu and x = 8) have been isolated in the presence of isonicotinic acid under solvothermal conditions. Structural analysis indicates that those three compounds are isostructural, featuring boat-shaped {Ln8} metal frameworks. Magnetic measurements reveal that 1-Gd exhibits a larger MCE with the maximum -ΔSm value of 31.77 J kg-1 K-1 at 2 K for ΔH = 7 T, while 2-Dy displays slow magnetization relaxation. Besides, the photoluminescence properties of 3-Eu were investigated.

4.
Dalton Trans ; 50(26): 9137-9143, 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34115085

RESUMO

Two captivating {P4Mo6}-based compounds, formulated as (H2bbi)2{[Co2(bbi)][Co2.33(H2O)4][H9.33CoP8Mo12O62]}·4H2O (1) and (H2bbi){[Zn(Hbbi)]2[Zn0.75(bbi)][K2Zn(H2O)4][H8.5ZnP8Mo12O62]} (2) [bbi = 1,1'-(1,4-butanediyl)bis(imidazole)], were successfully synthesized under hydrothermal conditions. Structural analysis demonstrates that compounds 1 and 2 are constructed from hourglass-shaped structures [M(P4Mo6O31)2]n- (M = Co, Zn), which are all made up of molybdophosphates and one transition metal ion as the central connecting node. Compounds 1 and 2 feature three-dimensional (3D) frameworks, which are all connected to form a 3D structure by metal ions and bbi ligands. More interestingly, compound 1 exhibits higher catalytic activity than 2 in CO2 photoreduction due to the suitable energy band structure of Co species in {P4Mo6} clusters. The CO yield was 3261 µmol g-1 with high selectivity in 8 h for compound 1 in photocatalytic CO2 reduction, which is highly promising in the photocatalytic field. Additionally, the photoluminescence properties of 2 were investigated.

5.
Dalton Trans ; 49(40): 14251-14257, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33026381

RESUMO

Two new bifunctional isolated hybrid compounds, [ε-PMoV8MoVI4O37(OH)3Zn4][iql]4·6H2O (1) and [ε-PMoV8MoVI4O38(OH)2Zn4][bipy]3[(CH3COO)(bipy)2Zn]·2H2O (2) (where iql = isoquinoline and bipy = 2,2'-bipyridine), based on Zn-ε-Keggin were successfully synthesized by self-assembly under hydrothermal conditions. It is interesting to note that acetate in 2 acted as a linker connecting the ε-Keggin anion with the one Zn atom (Zn5) and enabled the ε-Keggin anion to coordinate with more bipy ligands, culminating with a larger isolated system, which is the first reported isolated cluster of Zn5PMo12. Meanwhile, compounds 1-2 show great electrochemical behaviors and excellent electrocatalytic activity for the degradation of NaNO2. In addition, compound 2 displays better third-order NLO performance than 1 due to the presence of more conjugated rings, with a TPA cross section (σ) of 1819 GM, which suggests that compound 2 has the potential to function as a bifunctional material with tremendous prospects.

6.
Neurol Res ; 41(6): 519-527, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30759061

RESUMO

Background and Objectives: Studying the underlying mechanisms of opiate-induced hyperalgesia is fundamental to understanding and treating pain. Our previous study has proved that ephrinB/EphB signaling contributes to opiate-induced hyperagesia, but the manner in which ephrinB/EphB signaling acts on spinal nociceptive information networks to produce hyperalgesia remains unclear. Other studies have suggested that ephrinB/EphB signaling, NMDA receptor and COX-2 act together to participate in the modulation of nociceptive information processes at the spinal level. The objective of this research was to investigate the role of COX-2 in remifentanil-induced hyperalgesia and its relationship with ephrinB/EphB signaling. Methods: We characterized the remifentanil-induced pain behaviours by evaluating thermal hyperalgesia and mechanical allodynia in a mouse hind paw incisional model. Protein expression of COX-2 in spinal cord was assayed by western blotting and mRNA level of COX-2 was assayed by Real-time PCR (RT-PCR). Results: Continuing infusion of remifentanil produced thermal hyperalgesia and mechanical allodynia, which was accompanied by increased expression of spinal COX-2 protein and mRNA. This response was inhibited by pre-treatment with EphB2-Fc, an antagonist of ephrinB/EphB. SC58125 and NS398, inhibitors of COX-2, suppressed pain behaviours induced by remifentanil infusion and reversed the increased pain behaviours induced by intrathecal injection of ephrinB2-Fc, an agonist of ephrinB/EphB. Conclusions: Our findings confirmed that COX-2 is involved in remifentanil-induced hyperalgesia related to ephrinB/EphB signaling. EphrinB/EphB signaling might be the upstream of COX-2.


Assuntos
Ciclo-Oxigenase 2/metabolismo , Efrinas/metabolismo , Hiperalgesia/metabolismo , Remifentanil/farmacologia , Animais , Modelos Animais de Doenças , Hiperalgesia/induzido quimicamente , Injeções Espinhais , Camundongos , Pirazóis/farmacologia , Receptores de N-Metil-D-Aspartato/metabolismo , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo
7.
Rejuvenation Res ; 22(2): 138-145, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29932015

RESUMO

Chronic inflammation is a major driving factor for the development of colitis-associated cancer (CAC). It is extensively acknowledged that patients who have long-standing inflammation bowel disease are at high risk for developing CAC. However, the metabolic alteration by which chronic intestinal inflammation promotes colorectal cancer is unclear. In the present study, we constructed dextran sulfate sodium (DSS)-induced colitis mouse model to uncover possible alterations in the metabolism indexes. Interestingly, after DSS diet administration, the expression of metabolism indexes and c-Myc increased. Moreover, in vitro, we treated cells with IL-6 to simulate inflammatory microenvironment and found that glucose uptake, lactate production, and lactate dehydrogenase activity increased dramatically, mirroring what were observed in vivo. In addition, the associative inhibition of STAT3 and c-Myc could significantly block the expression of metabolic enzymes. With the inhibition of STAT3/c-Myc signaling, meanwhile, the upregulation of both cell glucose uptake and lactate production by IL-6 pretreatment was reduced simultaneously. Thus, our study indicates that inflammation could induce metabolic disorder by promoting STAT3 signaling and c-Myc activity. Collectively, we find that metabolic disruptions triggered by inflammatory signaling are associated with tumorigenesis via the STAT3/c-Myc axis.


Assuntos
Carcinogênese/metabolismo , Neoplasias Colorretais/metabolismo , Glicólise , Inflamação/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Animais , Linhagem Celular Tumoral , Colite/metabolismo , Colite/patologia , Sulfato de Dextrana/administração & dosagem , Dieta , Modelos Animais de Doenças , Glucose/metabolismo , Humanos , Inflamação/patologia , Ácido Láctico/biossíntese , Masculino , Camundongos Endogâmicos C57BL , Regulação para Cima
8.
Huan Jing Ke Xue ; 35(2): 669-77, 2014 Feb.
Artigo em Zh | MEDLINE | ID: mdl-24812963

RESUMO

To solve the problems of heavy metal pollution and agricultural wastes reclamation, spent substrate of pleurotus oyster was used as adsorbents to remove Cu2+ from aqueous solution. The effects of pH value, adsorption time, temperature and initial Cu2+ concentration on the adsorption behavior were determined by single factor experiments. The mechanisms were preliminarily investigated by SEM-EDX, FTIR and XRD analysis. The results of single factor experiments showed that the adsorption rate and capacity reached 74.46% and 0.7446 mg x g(-1) respectively at an adsorbent concentration of 10 g x L(-1), a pH of 6, an adsorption time of 120 min, an adsorption temperature of 30 degrees C and an initial Cu2+ concentration of 8 mg x L(-1). The experimental data fitted well with Langmuir isotherm models and R2 reached 0.994 9, indicating the adsorption was a monolayer chemisorption. SEM-EDX, FTIR and XRD analysis indicated that the adsorption process mainly depended on the physical and chemical adsorption onto the substrate surface through electrostatic attraction, complexation and coordination reaction. The -OH, -COOH and -NH were the functioning groups for Cu2+ adsorption.


Assuntos
Cobre/metabolismo , Recuperação e Remediação Ambiental/métodos , Pleurotus/metabolismo , Adsorção , Animais , Poluentes Ambientais/metabolismo , Concentração de Íons de Hidrogênio , Temperatura
9.
Exp Neurol ; 261: 475-85, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25108066

RESUMO

The brainstem is well recognized as a critical site for integrating descending modulatory systems that both inhibit and facilitate pain at the level of the spinal cord. The cerebrospinal fluid-contacting nucleus (CSF-contacting nucleus) distributes and localizes in the ventral periaqueductal central gray of the brainstem. Although emerging lines of evidence suggest that the CSF-contacting nucleus may be closely linked to transduction and regulation of pain signals, the definitive role of the CSF-contacting nucleus in pain modulation remains poorly understood. In the present study, we determined the role of the CSF-contacting nucleus in rat nocifensive behaviors after persistent pain by targeted ablation of the CSF-contacting nucleus in the brainstem using the cholera toxin subunit B-saporin (CB-SAP), a cytotoxin coupled to cholera toxin subunit B. Compared with CB/SAP, CB-SAP induced complete ablation of the CSF-contacting nucleus, and the CB-SAP-treated rats showed hypersensitivity in responses to acute nociceptive stimulation, and exacerbated spontaneous nocifensive responses induced by formalin, thermal hyperalgesia and mechanical allodynia induced by plantar incision. Furthermore, immunohistochemical experiments showed that the CSF-contacting nucleus was a cluster of 5-HT-containing neurons in the brainstem, and the spinal projection of serotonergic axons originating from the CSF-contacting nucleus constituted the descending 5-HT pathway to the spinal cord. CB-SAP induced significant downregulation of 5-HT in the spinal dorsal horn, and intrathecal injection of 5-HT significantly reversed hypersensitivity in responses to acute nociceptive stimulation in the CB-SAP-treated rats. These results indicate that the CSF-contacting nucleus 5-HT pathway is an important component of the endogenous descending inhibitory system in the control of spinal nociceptive transmission.


Assuntos
Tronco Encefálico/patologia , Líquido Cefalorraquidiano , Dor/patologia , Transdução de Sinais , Medula Espinal/patologia , Animais , Toxina da Cólera , Modelos Animais de Doenças , Formaldeído/toxicidade , Frequência Cardíaca/efeitos dos fármacos , Masculino , Rede Nervosa/patologia , Rede Nervosa/fisiopatologia , Vias Neurais/metabolismo , Vias Neurais/fisiopatologia , Dor/etiologia , Limiar da Dor/efeitos dos fármacos , Limiar da Dor/fisiologia , Ratos , Ratos Sprague-Dawley , Respiração/efeitos dos fármacos , Proteínas Inativadoras de Ribossomos Tipo 1 , Saporinas , Serotonina/farmacologia
10.
Int J Pharm ; 405(1-2): 1-8, 2011 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-21093564

RESUMO

A group of growth factors have been shown to play important roles in amelioration of the malfunction of the neurodegenerative diseases. However, the proteins or polypeptides passing across the blood-brain barrier (BBB) to access the brain parenchyma are relatively few so that it hinders the therapies in clinic. Here a genetically reconstructed fusion peptide of human epidermal growth factor (hEGF) with an undecapeptide YGRKKRRQRRR (P11) was used to investigate the permeability between the cell membrane and the BBB via rectal administration. The efficiency to rescue the Aß 22-35-induced dementia in mice was assessed after administration of P11-hEGF per rectal. Our results showed that P11-hEGF permeates across not only the 3T3 cell membrane in vitro, but also the endothelia of vessels after intravenous injection (IV), and the mucosa of the rectum after per rectal administration. Further results showed that the circulating P11-hEGF allowed penetrating through the blood-brain barrier and then getting into the brain manifesting biological responses. In the animal experiments, treatment with P11-hEGF not only ameliorated the dementia induced by Aß 22-35 but also rescued the dementia of the aged mice, no matter how it was administrated (IV or per rectal). These results suggest that the rectal non-invasive delivery of the P11 polypeptide-conjugated growth factor is an efficient way for BBB transduction, thus raises the hope of real therapeutic progress against neurodegenerative diseases.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Barreira Hematoencefálica/metabolismo , Demência/tratamento farmacológico , Fator de Crescimento Epidérmico/administração & dosagem , Oligopeptídeos/administração & dosagem , Proteínas Recombinantes de Fusão/farmacologia , Administração Retal , Animais , Encéfalo/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Demência/metabolismo , Fator de Crescimento Epidérmico/genética , Fator de Crescimento Epidérmico/farmacocinética , Fator de Crescimento Epidérmico/farmacologia , Humanos , Deficiências da Aprendizagem/tratamento farmacológico , Transtornos da Memória/tratamento farmacológico , Camundongos , Oligopeptídeos/farmacocinética , Oligopeptídeos/farmacologia , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/sangue , Proteínas Recombinantes de Fusão/farmacocinética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA