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1.
Artigo em Inglês | MEDLINE | ID: mdl-38363351

RESUMO

Dexmedetomidine has been used as a sedative drug in the clinic for a long time. Many studies demonstrated that the sedative mechanism of dexmedetomidine might be related to the activation of α2-adrenoceptor (α2AR). In addition, it was reported that dexmedetomidine had some affinity for the I1-imidazoline receptor (I1R); however, the role of I1R in dexmedetomidine-induced sedative effects and its possible mechanism are poorly studied. In the present study, we found that agmatine, an I1R agonist, was able to enhance the sedative effect of dexmedetomidine in mice. Efaroxan, an α2AR and I1R antagonist, could prevent and rescue the sedative action of dexmedetomidine in mice, and its preventive effect was better than atipamezole, the specific α2AR antagonist. Knockout of imidazoline receptor antisera-selected (IRAS), the functional I1R candidate protein, suppressed the dexmedetomidine-induced sedation. Moreover, IRAS knockout led to the inhibition of agmatine and efaroxan in regulating dexmedetomidine-induced sedative effects in mice, but not of atipamezole. We then used CHO cell lines that stably expressed α2AR and IRAS to investigate the possible molecular mechanism of IRAS in regulating the dexmedetomidine-induced sedative effect. The results showed that IRAS expression significantly up-regulated dexmedetomidine-induced ERK phosphorylation, which was enhanced by agmatine and inhibited by efaroxan at low concentrations. Therefore, by taking advantage of pharmacological and genetic approaches, our finding revealed the evidence that IRAS plays an important role in the sedative effects of dexmedetomidine, and the ERK signal pathway may be involved in the mechanism of IRAS in regulating dexmedetomidine-induced sedation. This study may offer valuable insights for the advancement of novel anesthetic adjuvants.

2.
Heliyon ; 9(4): e14816, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37035389

RESUMO

Increasing evidence has manifested that circular RNAs (circRNAs) exhibited critical function in regulating various signaling pathways related to hepatocellular carcinoma (HCC) recurrence. However, the role and mechanism of the circRNAs in the HCC early recurrence remain elusive. In this study, high-throughput RNA-sequencing (RNA-seq) analysis was conducted to identify the expression profile of circRNAs in HCC tissues and circ_0005218 was identified as one circRNA that significantly up-regulated in early recurrent HCC tissues. And patients with high expression of circ_0005218 showed worsen overall survival (OS) and disease-free survival (DFS). Moreover, the promotion effects of circ_0005218 on HCC cells in term of proliferation, invasion and metastasis were confirmed both in vitro and vivo by gain- and loss-of function assays. In addition, dual-luciferase reporter assays showed that circ_0005218 could competitively bind to micro-RNA (miR)-31-5p. Furthermore, we showed that suppression of CDK1 by miR-31-5p could be partially rescued by up-regulating circ_0005218. Taken together, the present study indicates that circ_0005218 absorbed miR-31-5p as a sponge to weaken its suppression on CDK1 expression, and thus boost HCC cell invasion and migration, which would act as a potential biomarker to predict the HCC early recurrence and as a new therapeutic target for treatment of HCC.

3.
Sci Adv ; 8(12): eabk0718, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35319995

RESUMO

Arc volcanics are more oxidized than mid-ocean ridge basalts (MORB), but it is debated whether this is a mantle feature or a result of magmatic evolution. Copper, a sulfur-loving element, has been used to trace the behavior of redox-sensitive sulfur during mantle melting and infer similar redox states of sub-arc and sub-ridge mantle. Previous studies, however, neglected elevated sulfur contents in the sub-arc mantle, leading to underestimation of oxygen fugacities, and did not recognize systematic Cu variations in arc volcanics. Here, we show that the Cu/Zr ratio is a sensitive indicator that responds to sulfur content, oxygen fugacity, and extent of melting of the mantle. Because of higher mantle S contents, Cu systematics of arc magmas require one log unit higher oxygen fugacities of sub-arc than sub-ridge mantle. Low Cu contents of thick-crusted arc volcanics result from low extents of melting of sulfur-rich mantle, obviating the need for deep crustal sulfide fractionation, with substantial implications for the origin of porphyry-Cu deposits.

4.
Acta Pharmacol Sin ; 43(9): 2276-2288, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35217811

RESUMO

Drug addiction is characterized by relapse when addicts are re-exposed to drug-associated environmental cues, but the neural mechanisms underlying cue-induced relapse are unclear. In the present study we investigated the role of a specific dopaminergic (DA) pathway from ventral tegmental area (VTA) to nucleus accumbens core (NAcore) in mouse cue-induced relapse. Optical intracranial self-stimulation (oICSS) was established in DAT-Cre transgenic mice. We showed that optogenetic excitation of DA neurons in the VTA or their projection terminals in NAcore, NAshell or infralimbic prefrontal cortex (PFC-IL) was rewarding. Furthermore, activation of the VTA-NAcore pathway alone was sufficient and necessary to induce reinstatement of oICSS. In cocaine self-administration model, cocaine-associated cues activated VTA DA neurons as assessed by intracellular GCaMP signals. Cue-induced reinstatement of cocaine-seeking was triggered by optogenetic stimulation of the VTA-NAcore pathway, and inhibited by chemogenetic inhibition of this pathway. Together, these results demonstrate that cue-induced reinstatement of reward seeking is in part mediated by activation of the VTA-NAcore DA pathway.


Assuntos
Cocaína , Dopamina , Animais , Cocaína/farmacologia , Sinais (Psicologia) , Comportamento de Procura de Droga , Camundongos , Camundongos Transgênicos , Núcleo Accumbens/fisiologia , Ratos , Ratos Sprague-Dawley , Recidiva , Recompensa , Autoadministração
5.
Neuropharmacology ; 208: 108986, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35134442

RESUMO

There is a lack of safe and effective non-opioid medications for the treatment of opioid addiction. Aquaporin-4 (AQP4), a water channel protein expressed in astrocytes, regulates the progression of neurological diseases. Our previous work demonstrated that AQP4 deficiency in mice attenuated morphine-induced physiological dependence. However, the role of AQP4 in the neurobiology of behaviours related to opioid addiction in mice remains unclear. Here, we report that Aqp4-knockout mice exhibited attenuated heroin consumption and heroin-seeking behaviours. Furthermore, Aqp4-knockout mice displayed diminished hyperactivity induced by morphine and heroin and subsequently showed dramatically inhibited morphine-induced behavioural sensitization. This attenuated hyperlocomotion to opioids was accompanied by a decreased dopamine response to the opioid-induced increase in the levels of extracellular dopamine in the NAc. In addition, Aqp4-knockout mice displayed upregulation of dopamine transporters in the striatum, suggesting a probable neurobiological mechanism for uptake of the extracellular dopamine. The present findings suggest that deficiency of AQP4 decreases opiate-induced drug seeking and taking behaviours, and AQP4 may be involved in the treatment of addiction. Therefore, the development of a pharmacological antagonist to AQP4 may be valuable to investigate as opioid addiction therapy.


Assuntos
Aquaporina 4/metabolismo , Comportamento Aditivo , Dependência de Morfina , Transtornos Relacionados ao Uso de Opioides , Analgésicos Opioides , Animais , Aquaporina 4/genética , Dopamina/metabolismo , Heroína/farmacologia , Camundongos , Camundongos Knockout , Morfina , Dependência de Morfina/metabolismo , Núcleo Accumbens , Transtornos Relacionados ao Uso de Opioides/metabolismo
6.
Metab Brain Dis ; 34(5): 1421-1430, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31313126

RESUMO

The precise contributions of ventral tegmental area (VTA) dopaminergic (DAergic) neurons to reward-related behaviors are a longstanding hot topic of debate. Whether the activity of VTA DAergic neurons directly modulates rewarding behaviors remains uncertain. In the present study, we investigated the fundamental role of VTA DAergic neurons in reward-related movement and reinforcement by employing dopamine transporter (DAT)-Cre transgenic mice expressing hM3Dq, hM4Di or channelrhodopsin 2 (ChR2) in VTA DAergic neurons through Cre-inducible adeno-associated viral vector transfection. On the one hand, locomotion was tested in an open field to examine motor activity when VTA DAergic neurons were stimulated or inhibited by injection of the hM3Dq or hM4Di ligand clozapine-N-oxide (CNO), respectively. CNO injection to selectively activate or inhibit VTA DAergic neurons significantly increased or decreased locomotor activity, respectively, compared with vehicle injection, indicating that VTA DAergic neuron stimulation is directly involved in the regulation of motor activity. On the other hand, we used the optical intracranial self-stimulation (oICSS) model to investigate the causal link between reinforcement and VTA DAergic neurons. Active poking behavior but not inactive poking behavior was significantly escalated in a frequency- and pulse duration-dependent manner. In addition, microdialysis revealed that the concentration of dopamine (DA) in the nucleus accumbens (NAc) was enhanced by selective optogenetic activation of VTA DAergic neurons. Furthermore, systemic administration of a DA D1 receptor antagonist significantly decreased oICSS reinforcement. Our research profoundly demonstrates a direct regulatory role of VTA DAergic neurons in movement and reinforcement and provides meaningful guidance for the development of novel treatment strategies for neuropsychiatric diseases related to the malfunction of the reward system.


Assuntos
Neurônios Dopaminérgicos/metabolismo , Atividade Motora/fisiologia , Área Tegmentar Ventral/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Clozapina/análogos & derivados , Clozapina/farmacologia , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Camundongos , Camundongos Transgênicos , Atividade Motora/efeitos dos fármacos , Optogenética , Recompensa , Autoestimulação , Área Tegmentar Ventral/efeitos dos fármacos
7.
Cancer Biol Ther ; 20(8): 1091-1096, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30991882

RESUMO

Nuclear protein in testis (NUT) midline carcinoma (NMC) is a rare malignant tumor defined by a unique chromosomal translocation of the NUT gene on chromosome 15q14. This very rare tumor is usually located in midline structures, especially in the head and neck region. However, there have been no previous reports of NMC arising from the eyes. Here, we first describe a case of NMC originating in the right orbit of a 60-year-old woman. A multimodality approach, including surgery, chemotherapy, radiotherapy, and target therapy, was adopted in clinical practice.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/genética , Proteínas Nucleares/genética , Proteínas Oncogênicas/genética , Órbita/patologia , Biópsia , Terapia Combinada , Feminino , Estudos de Associação Genética/métodos , Predisposição Genética para Doença , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Proteínas de Neoplasias , Tomografia Computadorizada por Raios X , Translocação Genética , Resultado do Tratamento
8.
Biochem Biophys Res Commun ; 512(3): 460-466, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30902386

RESUMO

Morphine is a potent opioid analgesic used to alleviate moderate or severe pain, but the development of drug tolerance and dependence limits its use in pain management. Our previous studies showed that the candidate protein for I1 imidazoline receptor, imidazoline receptor antisera-selected (IRAS)/Nischarin, interacts with µ opioid receptor (MOR) and modulates its trafficking. However, there is no report of the effect of IRAS on morphine tolerance and physical dependence. In the present study, we found that IRAS knockout (KO) mice showed exacerbated analgesic tolerance and physical dependence compared to wild-type (WT) mice by chronic morphine treatment. Chronic morphine treatment down-regulated the expression of MOR in spinal cord of IRAS KO mice, while had no significant effect on MOR expression in WT mice. We observed the compensatory increase of cAMP accumulation in spinal cord after morphine tolerance, and this change was more significant in KO mice than WT mice. Furthermore, KO mice showed more elevation in the phosphorylation of AMPA receptor GluR1-S845 than WT mice, while the total expression of GluR1 remained unchanged after morphine dependence. Altogether, these data suggest that IRAS may play an important role in the development of morphine tolerance and physical dependence in vivo through modulating MOR expression, as well as AMPA GluR1-S845 phosphorylation, which might be one of the mechanisms underlying the development of opiate addiction.


Assuntos
Analgésicos Opioides/farmacologia , Tolerância a Medicamentos , Receptores de Imidazolinas/metabolismo , Dependência de Morfina/metabolismo , Morfina/farmacologia , Animais , AMP Cíclico/metabolismo , Receptores de Imidazolinas/genética , Camundongos , Camundongos Knockout , Dependência de Morfina/genética
9.
Arch Virol ; 164(1): 83-90, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30284628

RESUMO

Porcine epidemic diarrhea (PED) is a highly contagious, acute enteric tract infectious disease of pigs (Sus domesticus) caused by porcine epidemic diarrhea virus (PEDV). PED is characterized by watery diarrhea, dehydration, weight loss, vomiting and death. PEDV damages pig intestinal epithelial tissue, causing intestinal hyperemia and atrophy of intestinal villi, with formation of intestinal epithelial cell cytoplasmic vacuoles. Since pig small intestinal epithelial cells (IECs) are target cells of PEDV infection, IEC cells were utilized as a model for studying changes in cellular activities post-PEDV infection. Monitoring of Na+-K+-ATPase and Ca2+-Mg2+-ATPase activities demonstrated that PEDV infection decreased these activities. In addition, IECs proliferation was shown to decrease after PEDV infection using an MTT assay. Moreover, IECs apoptosis detected by flow cytometry with propidium iodide (PI) staining was clearly shown to increase relative to the control group. Meanwhile, animal experiments indicated that PEDV virulence for IEC cells was greater than viral virulence for Vero cells, although this may be due to viral attenuation after numerous passages in the latter cell line. Collectively, these studies revealed viral pathogenic mechanisms in PEDV-infected IECs and offer a theoretical basis for PEDV prevention and control.


Assuntos
Infecções por Coronavirus/veterinária , Células Epiteliais/virologia , Mucosa Intestinal/citologia , Intestino Delgado/patologia , Vírus da Diarreia Epidêmica Suína/patogenicidade , Animais , ATPase de Ca(2+) e Mg(2+)/metabolismo , Sobrevivência Celular , Chlorocebus aethiops , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Células Epiteliais/patologia , Intestino Delgado/virologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Suínos , Células Vero , Virulência
10.
Acta Pharmacol Sin ; 40(5): 583-588, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30224637

RESUMO

Increasing preclinical evidence demonstrates that dopamine D3 receptor (D3R) antagonists are a potential option for the treatment of drug addiction. The reinstatement of the addiction can be triggered by environmental stimuli that acquire motivational salience through repeated associations with the drug's effects. YQA14 is a novel D3R antagonist that has exhibited pharmacotherapeutic efficacy in reducing cocaine and amphetamine reward and relapse to drug seeking in mice. In this study we investigated the effects of YQA14 on morphine-induced context-specific locomotor sensitization in mice. We showed that repeated injection of YQA14 (6.25-25 mg/kg every day ip) prior to morphine (10 mg/kg every day sc) not only inhibited the acquisition, but also significantly attenuated the expression of morphine-induced locomotor sensitization. Furthermore, in the expression phase, one single injection of YQA14 (6.25-25 mg/kg, ip) dose-dependently inhibited the expression of morphine-induced behavioral sensitization. Moreover, YQA14 inhibited the expression of morphine-induced behavioral sensitization in wild mice (WT), but not in D3R knockout (D3R-/-) mice in the expression phase. In addition, D3R-/- mice also displayed the reduction in the expression phase compared with WT mice. In summary, this study demonstrates that blockade or knockout of the D3R inhibits morphine-induced behavior sensitization, suggesting that D3R plays an important role in the pathogenesis and etiology of morphine addiction, and it might be a potential target for clinical management of opioid addiction.


Assuntos
Benzoxazóis/uso terapêutico , Antagonistas de Dopamina/uso terapêutico , Dependência de Morfina/prevenção & controle , Morfina/farmacologia , Atividade Motora/efeitos dos fármacos , Piperazinas/uso terapêutico , Receptores de Dopamina D3/antagonistas & inibidores , Animais , Benzoxazóis/administração & dosagem , Benzoxazóis/farmacocinética , Antagonistas de Dopamina/administração & dosagem , Antagonistas de Dopamina/farmacocinética , Comportamento de Procura de Droga , Injeções Intraperitoneais , Masculino , Camundongos Knockout , Morfina/administração & dosagem , Dependência de Morfina/etiologia , Dependência de Morfina/psicologia , Piperazinas/administração & dosagem , Piperazinas/farmacocinética , Receptores de Dopamina D3/genética
11.
JGH Open ; 2(1): 28-30, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30483559

RESUMO

In this study, we first evaluated that all of the studies included were randomized controlled trials (RCTs). Second, the number of patients in the present meta-analysis is larger than before, so the conclusion is more convincing.

12.
Oncol Lett ; 16(1): 55-58, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29928386

RESUMO

The aim of the study was to investigate possible effects of p57 on the growth of the human MCF-7 and rat SHZ-88 breast cancer cell lines. Specific oligonucleotide sequences containing small hairpin structure were inserted into a small interfering RNA (siRNA) expression vector. The human MCF-7 and rat SHZ-88 breast cancer cell lines were transfected with recombinant plasmids. The p57 gene expression was blocked in the human MCF-7 breast and rat SHZ-88 breast cancer cells, using chemically modified siRNA. The p57 expression level was evaluated using quantitative polymerase chain reaction (qPCR) and western blot analysis. Immunofluorescence was conducted to detect p57 expression in the breast cancer cells. Tetrazolium blue (MTT) method was employed to detect the effect of p57 inhibition on the proliferation of the MCF-7 and SHZ-88 cell lines. Cell proliferation in the experimental group was significantly reduced. Immunofluorescence assay results showed p57 siRNA effectively inhibited the p57 level in the MCF-7 and SHZ-88 cells. RT-PCR results showed that 48 h after transfection, the p57 mRNA level in the transfected group was significantly lower compared with the control group. In conclusion, p57 effectively inhibited the proliferation of breast cancer after stable interference.

13.
Wilderness Environ Med ; 29(1): 18-28, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29338990

RESUMO

INTRODUCTION: The Kham Tibetans are one of several Tibetan ethnic subgroups living in the Kham area of China. Because studies on the high-altitude adaptation of the Kham people are scant, the main aim of this study is to investigate whether the response to hypoxia, especially polycythemia status, in the Kham Tibetans is different from other Tibetan ethnic subgroups. METHODS: The primary investigation was conducted on 346 native Kham Tibetan adults (268 men and 78 women) from 3 herdsmen villages located in Hongyuan County situated at an altitude of greater than 3600 m. The participants were aged 46.2±14.1 (21-82; mean±SD with range) years. Anthropometric measurements such as weight, height, waist circumference, body mass index, and blood pressure, as well as laboratory blood tests such as glycosylated hemoglobin, hemoglobin, total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and uric acid were analyzed. RESULTS: The concentrations of hemoglobin were 171.3±12.9 (66-229) mg·L-1 and 151.4±16.4 (86-190) mg·L-1 in men and women, respectively. The frequency of polycythemia was found to be 25.5 and 21.8% in men and women, respectively. Polycythemia was found to be significantly associated with glycosylated hemoglobin concentrations, hypertension, and hyperuricemia (P=0.002, 0.023, and 0.009, respectively). CONCLUSIONS: There is a higher frequency of polycythemia in the Kham Tibetans when compared with reported studies from other Tibetan ethnic subgroups living on the Qinghai-Tibet plateau.


Assuntos
Dislipidemias/epidemiologia , Hiperglicemia/epidemiologia , Hipertensão/epidemiologia , Hiperuricemia/epidemiologia , Sobrepeso/epidemiologia , Policitemia/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Altitude , China/epidemiologia , Dislipidemias/etiologia , Feminino , Humanos , Hiperglicemia/etiologia , Hipertensão/etiologia , Hiperuricemia/etiologia , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Obesidade/etiologia , Sobrepeso/etiologia , Policitemia/etiologia , Tibet/etnologia , Adulto Jovem
15.
Metab Brain Dis ; 32(5): 1491-1502, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28523568

RESUMO

Dopamine (DA) neurons in the ventral tegmental area (VTA) are predicted to play important roles in reward. In pharmacological studies, the rewarding effects of methamphetamine are mediated by DA neurons localized in the VTA. The nucleus accumbens (NAc) and medial prefrontal cortices (mPFC) are the main projections from the VTA. However, the role of these projections remains unclear, particularly the mPFC projections. In the present study, DAT-Cre transgenic mice received an injection of adeno-associated viral vectors encoding channelrhodopsin2 (ChR2) or control vector into the VTA resulting in the selective expression of these opsins in DA neurons. Then, we stimulated the VTA, NAc (core and shell) or mPFC (prelimbic cortex (PL) and infralimbic cortex (IL)) via an optical fiber. The mice with ChR2 learned instrumental responses corresponding to the delivery of photostimulation into the VTA. The projections to the NAc core and shell from the VTA and stimulation of the NAc subregion both induced reinforcement. For projections to the mPFC (IL and PL), we verified that stimulation of the IL induced reinforcement dependent on DA from the VTA but not the PL. Furthermore, micro-infusion of methamphetamine into the NAc core and NAc shell also induced hyper-locomotion in a dose-dependent manner with a slight tendency of increased excitation of the IL but not PL. Taken together, excitation of the projection into the NAc core, NAc shell and IL elicited positive behavior during reward.


Assuntos
Condicionamento Operante/fisiologia , Neurônios Dopaminérgicos/fisiologia , Núcleo Accumbens/fisiologia , Optogenética , Córtex Pré-Frontal/fisiologia , Área Tegmentar Ventral/fisiologia , Animais , Comportamento Animal/fisiologia , Condicionamento Operante/efeitos dos fármacos , Dopaminérgicos/administração & dosagem , Dopaminérgicos/farmacologia , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Relação Dose-Resposta a Droga , Masculino , Metanfetamina/administração & dosagem , Metanfetamina/farmacologia , Camundongos , Camundongos Transgênicos , Atividade Motora/efeitos dos fármacos , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiologia , Núcleo Accumbens/diagnóstico por imagem , Estimulação Luminosa , Córtex Pré-Frontal/diagnóstico por imagem , Autoestimulação , Área Tegmentar Ventral/diagnóstico por imagem
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(3): 665-71, 2017 Mar.
Artigo em Chinês, Inglês | MEDLINE | ID: mdl-30148336

RESUMO

With the rapid development of economy and society in our country, atmospheric haze has become a prominent environmental issue. Measuring haze particles is also important. Polarized ultraviolet light is scattered by atmospheric haze particles, the changes of scattered light polarization state(Stokes vector and the degree of polarization) in atmospheric haze can reflect the physical properties of the particles (particle size and the complex refractive index, etc.). Based on Mie scattering theory, line-of-sight and non-line-of-sight of a single UV scattering model is established. On one hand, the effects of the physical properties of the single and chain-structure spherical particles for the UV light polarization properties are studied. On the other hand, based on Monte Carlo Simulation, the impacts of haze particle concentration on polarization state at a fixed particle size distribution are discussed. The simulation results show that: with the particle size of single spherical increasing, the scattered light intensity in Stokes vector (Is) is significantly enhanced. Is shows a trend of first increase then decrease with the increase of the complex refractive index's imaginary part. The degree of polarization is constantly increasing with the increase of the complex refractive index's imaginary part and the imaginary part of the complex refractive index is small, the degree of polarization trend of fast increase. With the concentration of particles in haze increasing when the distribution of particle size is a fixed value, haze particles scattering coefficient, extinction coefficient and absorption coefficient showed a linear increase, while Is is reduced after the first increases. For chain-structure spherical particles, with the increase of the number of particles, Is shows a tendency to increase. As the same time, degrees of polarization distinguish whether the chain-structure spherical particles are made up by the same spherical particle. In the chain-structure consisted of same spherical particles, Is increases linearly with the increase of the number of particles and the degree of polarization does not change. The Is under the chain-structure consisted of different spherical particles can distinguish particles' physical properties according to the changing trend of scattering light polarization state.


Assuntos
Espalhamento de Radiação , Raios Ultravioleta , Luz , Tamanho da Partícula , Refratometria
17.
Asian Pac J Cancer Prev ; 17(5): 2711-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27268656

RESUMO

BACKGROUND: Through search the possible randomized control trials, we make a renewed meta-analysis in order to assess the impact of aspirin in preventing the recurrence of colorectal adenoma. MATERIALS AND METHODS: The Medicine/PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), Chinese biomedical literature service system (SinoMed) databases were searched for the related randomized controlled trials until to the April 2016. Three different authors respectively evaluated the quality of studies and extracted data, and we used the STATA software to analyze, investigate heterogeneity between the data, using the fixed-effects model to calculate and merge data. RESULTS: 7 papers were included the renewed meta- analysis, among these studies, two pairs were identified as representing the same study population, with the only difference being the duration of follow-up. Thus there were only five papers included our meta-analysis, and one Chinese paper were also included the work. Results were categorized by the length of follow-up, different kinds of people, varied dose of oral aspirin. The relative of adenoma in patients taking aspirin vs placebo were 0.73 (95% CI 0.55-0.98, P=0.039) with 1 year follow up; 0.84 (95% CI 0.72-0.98, P=0.484) with greater than 1 year follow up; for the advanced adenoma, the RR 0.68 (95% CI 0.49-0.94, P=0.582),for one year; RR=0.75 (95% CI 0.52-1.07, P=0.552) for greater one year. Furthermore the white population could divided into two subgroups according to the different length of follow-up time. When the length of follow-up time less than 3-year, The RR of two subgroups respective were RR=0.86 (95% CI 0.76-0.98, P=0.332), I2=0%, RR=0.68 (95% CI 0.47-0.98, P=0.552), I2=64.6%, But with the extension of follow-up time greater than 2-year, with the white, oral aspirin without considering dose had no efficacy on preventing the recurrence of any adenoma, the RR was 0.86 (95% CI 0.71-1.05, P=0.302), I2=16.4%. CONCLUSIONS: This meta-analysis indicated that oral aspirin is associated with a remarkable decrease in the recurrence of any adenoma and advanced adenomas in patients follow-up for 1 year without concerning the dose of aspirin, but with the extension of follow-up time for greater than 1 year, oral aspirin can be effective on preventing the recurrence of any adenoma, but for the advanced adenoma, the result indicated that oral aspirin had no efficacy, According to the inclusion of ethnic groups, we also divided relevant papers into two subgroups as the yellow and white group. Then the follow-up time was less than 3 years, oral aspirin without considering the dose, had an significant efficacy on preventing the recurrence of any adenoma. But with the follow-up greater than 2 years, oral aspirin had no effect in the white.


Assuntos
Adenoma/tratamento farmacológico , Anti-Inflamatórios não Esteroides/uso terapêutico , Aspirina/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Recidiva Local de Neoplasia/prevenção & controle , Humanos , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto
18.
Biomarkers ; 21(8): 678-685, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27328859

RESUMO

Drug addiction places a significant burden on society and individuals. Proteomics and metabolomics approaches pave the road for searching potential biomarkers to assist the diagnosis and treatment. This review summarized putative drug addiction-related biomarkers in proteomics and metabolomics studies and discussed challenges and prospects in future studies. Alterations of several hundred proteins and metabolites were reported when exposure to abused drug, which enriched in energy metabolism, oxidative stress response, protein modification and degradation, synaptic function and neurotrasmission, etc. Hsp70, peroxiredoxin-6 and α- and ß-synuclein, as well as n-methylserotonin and purine metabolites, were promising as potential biomarker for drug addiction.

19.
Neurosci Bull ; 32(6): 523-530, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27161447

RESUMO

Chronic exposure to opioids induces adaptation of glutamate neurotransmission, which plays a crucial role in addiction. Our previous studies revealed that agmatine attenuates opioid addiction and prevents the adaptation of glutamate neurotransmission in the nucleus accumbens of chronic morphine-treated rats. The hippocampus is important for drug addiction; however, whether adaptation of glutamate neurotransmission is modulated by agmatine in the hippocampus remains unknown. Here, we found that continuous pretreatment of rats with ascending doses of morphine for 5 days resulted in an increase in the hippocampal extracellular glutamate level induced by naloxone (2 mg/kg, i.p.) precipitation. Agmatine (20 mg/kg, s.c.) administered concurrently with morphine for 5 days attenuated the elevation of extracellular glutamate levels induced by naloxone precipitation. Furthermore, in the hippocampal synaptosome model, agmatine decreased the release and increased the uptake of glutamate in synaptosomes from chronic morphine-treated rats, which might contribute to the reduced elevation of glutamate levels induced by agmatine. We also found that expression of the hippocampal NR2B subunit, rather than the NR1 subunit, of N-methyl-D-aspartate receptors (NMDARs) was down-regulated after chronic morphine treatment, and agmatine inhibited this reduction. Taken together, agmatine prevented the adaptation of the hippocampal glutamate system caused by chronic exposure to morphine, including modulating extracellular glutamate concentration and NMDAR expression, which might be one of the mechanisms underlying the attenuation of opioid addiction by agmatine.


Assuntos
Agmatina/farmacologia , Líquido Extracelular/efeitos dos fármacos , Ácido Glutâmico/metabolismo , Hipocampo , Morfina/farmacologia , Entorpecentes/farmacologia , Adaptação Fisiológica/efeitos dos fármacos , Análise de Variância , Animais , Regulação para Baixo/efeitos dos fármacos , Interações Medicamentosas , Técnicas Eletroquímicas , Líquido Extracelular/metabolismo , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Ratos , Ratos Wistar , Receptores de N-Metil-D-Aspartato/metabolismo , Fatores de Tempo
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