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1.
J Endocrinol Invest ; 47(2): 367-376, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37458930

RESUMO

BACKGROUND: Serum lipid levels are associated with cancer risk. However, there still have uncertainties about the single and combined effects of low lipid levels on cancer risk. METHODS: A prospective cohort study of 33,773 adults in Shanghai between 2016 and 2017 was conducted. Total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) levels were measured. Cox proportional hazard models were used to assess the association of single and combined lipids with overall, lung, colon, rectal, thyroid gland, stomach, and female breast cancers. The effect of the combination of abnormal lipid score and lifestyle on cancer was also estimated. RESULTS: A total of 926 incident cancer cases were identified. In the RCS analysis, hazard ratios (HRs) of overall cancer for individuals with TC < 5.18 mmol/L or with LDL-C < 3.40 mmol/L were higher. Low TC was associated with higher colorectal cancer risk (HR [95% CI] = 1.76 [1.09-2.84]) and low HDL-C increased thyroid cancer risk by 90%. Abnormal lipid score was linearly and positively associated with cancer risk, and smokers with high abnormal lipid scores had a higher cancer risk, compared to non-smokers with low abnormal lipid scores (P < 0.05). CONCLUSIONS: Low TC levels were associated with an increased risk of overall and colorectal cancer. More attention should be paid to participants with high abnormal lipid scores and unhealthy lifestyles who may have a higher risk of developing cancer. Determining the specific and comprehensive lipid combinations that affect tumorigenesis remains a valuable challenge.


Assuntos
Neoplasias Colorretais , Lipídeos , Adulto , Humanos , Feminino , Estudos Prospectivos , LDL-Colesterol , HDL-Colesterol , Fatores de Risco , China/epidemiologia , Triglicerídeos
2.
Environ Res ; 167: 98-114, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30014901

RESUMO

In this study, a multistage type-2-fuzzy interval-stochastic programming (MTIP) method is developed, which extends upon the existing multistage stochastic programming (MSP) by allowing uncertainties expressed as probabilistic distributions, interval values and type-2 fuzzy sets to be effectively incorporated within the optimization framework. Through coupling air quality index (AQI) with MTIP, an AQI-MTIP model is formulated for energy and environmental systems (EES) management of Tianjin. A number of scenarios based on changed AQIs are examined to analyze the impacts of environmental requirements on the city's energy system. Results indicate that (i) with the improvement of environmental requirement, utilization of clean energies (especially natural gas) is provoked markedly; (ii) PM2.5 is the primary pollutant, 64.50% of which should be reduced each period to maintain the city's air quality at a health-safe level. These findings can help decision makers adjust energy structure, make effective mitigation strategy, and gain deep insight into the relationship between energy consumption and environmental requirement.


Assuntos
Poluição do Ar , Fontes de Energia Elétrica , Fontes Geradoras de Energia , Cidades , Lógica Fuzzy , Humanos , Incerteza
3.
Zhonghua Xin Xue Guan Bing Za Zhi ; 46(6): 475-479, 2018 Jun 24.
Artigo em Chinês | MEDLINE | ID: mdl-29925185

RESUMO

Objective: To investigate the effect and related mechanisms of RTA-408 on rat vascular smooth muscle cells (VSMCs) calcification induced by advanced glycation end products(AGE). Methods: VSMCs were isolated from the aorta of Sprague Dawley rats and cultured in vitro. The fifth generation of VSMCs were randomly divided into 4 groups with random number table including control group(cells were incubated with normal medium for 2 days, then incubated with bovine serum albumin for 5 days),AGE group (cells were incubated with normal medium for 2 days, then incubated with 200 mg/L AGE for 5 days), experimental group(cells were incubated with 100 nmol/L RTA-408 for 2 days,then incubated with 200 mg/L AGE for 5 days),and RTA group(cells were incubated with 100 nmol/L RTA-408 for 2 days,then incubated with bovine serum albumin for 5 days). Cytosolic calciumin VSMC was measured using arsenazo Ⅲ assay. Von Kossa staining was utilized to detect the calcium deposition.The contents of malondialdehyde(MDA) and superoxide dismutase(SOD) in VSMCs were tested by appropriate kits.The protein expressions of osteopontin (OPN), alkaline phosphatase (ALP), nuclear factor E2 related factor 2(Nrf2), and NAD(P)H: quinone oxidoreductase 1(NQO1) were examined using Western blot. Results: (1) Cytosolic calciumconcentration was significantly higher in AGE group than in control group((2.43±0.15) mmol/L vs. (1.23±0.09) mmol/L, P<0.01), which was significantly reduced in experimental group((1.62±0.18) mmol/L,P<0.01 vs. AGE group). (2) Calcium deposition in VSMCs was significantly upregulated in AGE group than in control group(3.64±0.50 vs. 1.00±0.12, P<0.01), and was downregulated in experimental group (1.56±0.37, P<0.01 vs. AGE group). (3) The MDA contents were higher((3.79±0.27) nmol/mg prot vs.(1.99±0.15) nmol/mg prot, P<0.01), while the SOD activities were lower((308.45±14.28) U/mg prot vs. (428.58±11.00) U/mg prot, P<0.01) in AGE group than in control group. The MDA contents were lower((2.37±0.19) nmol/mg prot vs. (3.79±0.27) nmol/mg prot, P<0.01),while the SOD activities were higher((391.03±22.92) U/mg prot vs. (308.45±14.28) U/mg prot, P<0.05)in experimental group compared with AGE group. (4) The relative expressions of OPN and ALP were higher in AGE group than in control group(3.06±0.21 vs. 1.00±0.07, and 2.89±0.29 vs. 1.00±0.10,both P<0.01), both (OPN(1.15±0.12) and ALP(1.45±0.15)) were downregulated in experimental group (both P<0.01 vs. AGE group). (5) The relative protein expressions of Nrf2 and NQO1 in experimental group were higher than AGE group(2.37±0.17 vs. 1.17±0.09, and 3.91±0.18 vs. 1.05±0.08, both P<0.01). Conclusion: Activation of nrf2/NQO1 signaling pathway by RTA-408 can reduce the AGE-induced VSMC calcification through attenuating oxidative injury.


Assuntos
Produtos Finais de Glicação Avançada , Músculo Liso Vascular , Triterpenos , Calcificação Vascular , Animais , Células Cultivadas , Produtos Finais de Glicação Avançada/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Triterpenos/farmacologia , Calcificação Vascular/tratamento farmacológico
4.
Environ Res ; 166: 276-289, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29908459

RESUMO

In this study, a stepwise cluster modeling approach (SCMA) is developed for analyzing urban ecosystem variation via Normalized Difference Vegetation Index (NDVI). NDVI is an indicator of vegetation growth and coverage and useful in reflecting urban ecosystem. SCMA is established on a cluster tree that can characterize the complex relationship between independent and dependent variables. SCMA is applied to the City of Dongguan for simulating the urban NDVI and identifying associated drivers of human activity, topography and meteorology without specific functions. Results show that SCMA performances better than conventional statistical methods, illustrating the ability of SCMA in capturing the complex and nonlinear features of urban ecosystem. Results disclose that human activities play negative effects on NDVI due to the destruction of green space for pursuing more space for buildings. NDVI reduces gradually from the south part to the north part of Dongguan due to increased gross domestic product and population density, indicating that the ecosystem in Dongguan is better in the south part. NDVI in the northeast part (dominated by agriculture) is sensitive to the growth of economy and population. More attention should be paid to this part for sustainable development, such as increasing afforestation, planting grass and constructing parks. Precipitation has a positive effect on NDVI due to the promotion of soil moisture that is beneficial to plants' growth. Awareness of these complexities is helpful for sustainable development of urban ecosystem.


Assuntos
Clima , Ecossistema , China , Cidades , Plantas , Desenvolvimento Sustentável
5.
Transplant Proc ; 49(6): 1336-1343, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28736004

RESUMO

BACKGROUND: Gingival overgrowth (GO) induced by cyclosporine (CsA), one of the common complications after kidney transplantation, is associated with a genetic component. However, the effect of TGF-ß1 and MDR1 gene polymorphisms on the pathogenesis of CsA-induced GO remains to be determined. This study aimed to determine the association between TGF-ß1 and MDR1 gene polymorphisms and CsA-induced GO in kidney transplant recipients. METHODS: The Pubmed, Embase, Cochrane Library, and Chinese CNKI (China National Knowledge Infrastructure) and Wanfang databases were comprehensively searched. Data were extracted and pooled results estimated from odds ratios (ORs) and 95% confidence intervals (CIs). In addition, quality assessment and publication bias of each eligible study were examined. RESULTS: Three trials focusing on the relationship between TGF-ß1 +869T>C and +915G>C and 3 studies on MDR1 C3435T gene polymorphisms and the onset of CsA-induced GO were included. No association between the +869T>C polymorphism and CsA-induced GO was found in the dominant model (TT+TC vs CC: OR, 0.77; 95% CI, 0.29-2.10; P = .614). In the recessive model, no association was found between the +915G>C polymorphism and CsA-induced GO (CC vs GG+GC: OR, 1.40; 95% CI, 0.81-2.43; P = .225). And in the dominant model, no significance was calculated between MDR1 C3435T gene polymorphisms and CsA-induced GO in kidney transplant recipients (TT vs CC+CT: OR, 1.14; 95% CI, 0.62-2.09; P = .68). CONCLUSIONS: No significant association exists between TGF-ß1 +869T>C, and +915G>C and MDR1 C3435T gene polymorphisms and the pathogenesis of CsA-induced GO in kidney transplant recipients.


Assuntos
Crescimento Excessivo da Gengiva/induzido quimicamente , Crescimento Excessivo da Gengiva/genética , Transplante de Rim , Polimorfismo Genético , Fator de Crescimento Transformador beta1/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Povo Asiático/genética , China , Ciclosporina/efeitos adversos , Feminino , Humanos , Imunossupressores/efeitos adversos , Masculino , Razão de Chances , Período Pós-Operatório
6.
J Psychopharmacol ; 31(8): 1027-1034, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28741422

RESUMO

BACKGROUND: Cannabis exposure, particularly heavy cannabis use, has been associated with neuroanatomical alterations in regions rich with cannabinoid receptors such as the hippocampus in some but not in other (mainly cross-sectional) studies. However, it remains unclear whether continued heavy cannabis use alters hippocampal volume, and whether an earlier age of onset and/or a higher dosage exacerbate these changes. METHODS: Twenty heavy cannabis users (mean age 21 years, range 18-24 years) and 23 matched non-cannabis using healthy controls were submitted to a comprehensive psychological assessment and magnetic resonance imaging scan at baseline and at follow-up (average of 39 months post-baseline; standard deviation=2.4). Cannabis users started smoking around 16 years and smoked on average five days per week. A novel aspect of the current study is that hippocampal volume estimates were obtained from manual tracing the hippocampus on T1-weighted anatomical magnetic resonance imaging scans, using a previously validated protocol. RESULTS: Compared to controls, cannabis users did not show hippocampal volume alterations at either baseline or follow-up. Hippocampal volumes increased over time in both cannabis users and controls, following similar trajectories of increase. Cannabis dose and age of onset of cannabis use did not affect hippocampal volumes. CONCLUSIONS: Continued heavy cannabis use did not affect hippocampal neuroanatomical changes in early adulthood. This contrasts with prior evidence on alterations in this region in samples of older adult cannabis users. In young adults using cannabis at this level, cannabis use may not be heavy enough to affect hippocampal neuroanatomy.


Assuntos
Hipocampo/patologia , Fumar Maconha/patologia , Adolescente , Estudos de Casos e Controles , Feminino , Hipocampo/diagnóstico por imagem , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Neuroimagem , Adulto Jovem
9.
Transl Psychiatry ; 7(1): e1011, 2017 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-28117843

RESUMO

Lithium and quetiapine are effective treatments for bipolar disorder, but their potential neuroprotective effects in humans remain unclear. A single blinded equivalence randomized controlled maintenance trial was conducted in a prospective cohort of first-episode mania (FEM) patients (n=26) to longitudinally compare the putative protective effects of lithium and quetapine on grey and white matter volume. A healthy control sample was also collected (n=20). Using structural MRI scans, voxel-wise grey and white matter volumes at baseline and changes over time in response to treatment were investigated. Patients were assessed at three time points (baseline, 3 and 12-month follow-up), whereas healthy controls were assessed at two time points (baseline and 12-month follow-up). Patients were randomized to lithium (serum level 0.6 mmol l-1, n=20) or quetiapine (flexibly dosed up to 800 mg per day, n=19) monotherapy. At baseline, compared with healthy control subjects, patients with FEM showed reduced grey matter in the orbitofrontal cortex, anterior cingulate, inferior frontal gyrus and cerebellum. In addition, patients had reduced internal capsule white matter volume bilaterally (t1,66>3.20, P<0.01). Longitudinally, there was a significant treatment × time effect only in the white matter of the left internal capsule (F2,112=8.54, P<0.01). Post hoc testing showed that, compared with baseline, lithium was more effective than quetiapine in slowing the progression of white matter volume reduction after 12 months (t1,24=3.76, P<0.01). Our data support the role of lithium but not quetiapine therapy in limiting white matter reduction early in the illness course after FEM.


Assuntos
Antimaníacos/uso terapêutico , Antipsicóticos/uso terapêutico , Transtorno Bipolar/tratamento farmacológico , Substância Cinzenta/diagnóstico por imagem , Compostos de Lítio/uso terapêutico , Fumarato de Quetiapina/uso terapêutico , Substância Branca/diagnóstico por imagem , Transtorno Bipolar/diagnóstico por imagem , Feminino , Substância Cinzenta/patologia , Humanos , Quimioterapia de Manutenção , Masculino , Fármacos Neuroprotetores , Tamanho do Órgão , Método Simples-Cego , Substância Branca/patologia , Adulto Jovem
10.
Brain Imaging Behav ; 11(2): 333-345, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27848149

RESUMO

An active cognitive lifestyle has been suggested to have a protective role in the long-term maintenance of cognition. Amongst healthy older adults, more managerial or supervisory experiences in midlife are linked to a slower hippocampal atrophy rate in late life. Yet whether similar links exist in individuals with Mild Cognitive Impairment (MCI) is not known, nor whether these differences have any functional implications. 68 volunteers from the Sydney SMART Trial, diagnosed with non-amnestic MCI, were divided into high and low managerial experience (HME/LME) during their working life. All participants underwent neuropsychological testing, structural and resting-state functional MRI. Group comparisons were performed on hippocampal volume, morphology, hippocampal seed-based functional connectivity, memory and executive function and self-ratings of memory proficiency. HME was linked to better memory function (p = 0.024), mediated by larger hippocampal volume (p = 0.025). More specifically, deformation analysis found HME had relatively more volume in the CA1 sub-region of the hippocampus (p < 0.05). Paradoxically, this group rated their memory proficiency worse (p = 0.004), a result correlated with diminished functional connectivity between the right hippocampus and right prefrontal cortex (p < 0.001). Finally, hierarchical regression modelling substantiated this double dissociation.


Assuntos
Envelhecimento/patologia , Envelhecimento/fisiologia , Emprego , Função Executiva/fisiologia , Hipocampo/patologia , Hipocampo/fisiologia , Liderança , Idoso , Idoso de 80 Anos ou mais , Mapeamento Encefálico , Feminino , Estilo de Vida Saudável/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão/fisiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Transl Psychiatry ; 6(6): e841, 2016 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-27327256

RESUMO

Multiple cross-sectional imaging studies have identified structural abnormalities in prefrontal, temporal and limbic regions related to conduct problems (CPs). However, the relationship between development of such neurobiological deficits and developmental pathways of CPs has remained unclear. The current study investigated distinct trajectories of CP and related trajectories of cortical thickness within a community-based sample of adolescents (n=239), age range 12-19, to address this gap. Three trajectory classes were revealed using latent class growth analyses (LCGAs), comprising a 'desisting' CP group, an 'intermediate' CP group and a 'stable low' CP group. Structural magnetic resonance imaging (MRI) scans were collected with a subgroup of 171 adolescents at three waves throughout adolescence (ages 12, 16 and 19). Generalized estimating equation (GEE) analysis-comparing longitudinal changes in cortical thickness and subcortical volume between CP groups for several regions of interest (ROIs)-showed that these CP groups had differential trajectories of cortical thickness in the dorsolateral prefrontal cortex (dl-PFC), and the anterior cingulate cortex (ACC), and volume of the hippocampus. Adolescents in the desisting CP group showed an attenuation of the typical pattern of cortical thinning as present in the intermediate and stable low CP groups, in addition to an exaggeration of the typical pattern of hippocampal volume increase. These findings suggest that a deviant cortical thickness trajectory was related to a desisting CP pathway across adolescence. Such deviant neurodevelopmental growth trajectories may act as an underlying mechanism for developmental CP pathways, and possibly distinguish desisting antisocial adolescents.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Transtorno da Conduta/diagnóstico por imagem , Transtorno da Conduta/patologia , Imageamento por Ressonância Magnética , Adolescente , Transtorno da Personalidade Antissocial/diagnóstico por imagem , Transtorno da Personalidade Antissocial/patologia , Transtorno da Personalidade Antissocial/psicologia , Mapeamento Encefálico , Criança , Transtorno da Conduta/psicologia , Feminino , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Humanos , Controle Interno-Externo , Estudos Longitudinais , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/patologia , Tamanho do Órgão , Inquéritos e Questionários
14.
Mol Psychiatry ; 21(11): 1633-1642, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27001615

RESUMO

Physical and cognitive exercise may prevent or delay dementia in later life but the neural mechanisms underlying these therapeutic benefits are largely unknown. We examined structural and functional magnetic resonance imaging (MRI) brain changes after 6 months of progressive resistance training (PRT), computerized cognitive training (CCT) or combined intervention. A total of 100 older individuals (68 females, average age=70.1, s.d.±6.7, 55-87 years) with dementia prodrome mild cognitive impairment were recruited in the SMART (Study of Mental Activity and Resistance Training) Trial. Participants were randomly assigned into four intervention groups: PRT+CCT, PRT+SHAM CCT, CCT+SHAM PRT and double SHAM. Multimodal MRI was conducted at baseline and at 6 months of follow-up (immediately after training) to measure structural and spontaneous functional changes in the brain, with a focus on the hippocampus and posterior cingulate regions. Participants' cognitive changes were also assessed before and after training. We found that PRT but not CCT significantly improved global cognition (F(90)=4.1, P<0.05) as well as expanded gray matter in the posterior cingulate (Pcorrected <0.05), and these changes were related to each other (r=0.25, P=0.03). PRT also reversed progression of white matter hyperintensities, a biomarker of cerebrovascular disease, in several brain areas. In contrast, CCT but not PRT attenuated decline in overall memory performance (F(90)=5.7, P<0.02), mediated by enhanced functional connectivity between the hippocampus and superior frontal cortex. Our findings indicate that physical and cognitive training depend on discrete neuronal mechanisms for their therapeutic efficacy, information that may help develop targeted lifestyle-based preventative strategies.


Assuntos
Cognição/fisiologia , Memória/fisiologia , Treinamento Resistido/métodos , Idoso , Idoso de 80 Anos ou mais , Encéfalo/patologia , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/terapia , Exercício Físico/fisiologia , Feminino , Substância Cinzenta/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Relação Estrutura-Atividade
15.
Transl Psychiatry ; 6: e710, 2016 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-26756903

RESUMO

Shifting policies towards legalisation of cannabis for therapeutic and recreational use raise significant ethical issues for health-care providers seeking evidence-based recommendations. We investigated whether heavy cannabis use is associated with persistent harms to the hippocampus, if exposure to cannabidiol offers protection, and whether recovery occurs with abstinence. To do this, we assessed 111 participants: 74 long-term regular cannabis users (with an average of 15.4 years of use) and 37 non-user healthy controls. Cannabis users included subgroups of participants who were either exposed to Δ9-tetrahydrocannabinol (THC) but not to cannabidiol (CBD) or exposed to both, and former users with sustained abstinence. Participants underwent magnetic resonance imaging from which three measures of hippocampal integrity were assessed: (i) volume; (ii) fractional anisotropy; and (iii) N-acetylaspartate (NAA). Three curve-fitting models across the entire sample were tested for each measure to examine whether cannabis-related hippocampal harms are persistent, can be minimised (protected) by exposure to CBD or recovered through long-term abstinence. These analyses supported a protection and recovery model for hippocampal volume (P=0.003) and NAA (P=0.001). Further pairwise analyses showed that cannabis users had smaller hippocampal volumes relative to controls. Users not exposed to CBD had 11% reduced volumes and 15% lower NAA concentrations. Users exposed to CBD and former users did not differ from controls on any measure. Ongoing cannabis use is associated with harms to brain health, underpinned by chronic exposure to THC. However, such harms are minimised by CBD, and can be recovered with extended periods of abstinence.


Assuntos
Canabidiol/farmacologia , Cannabis/efeitos adversos , Dronabinol/farmacologia , Hipocampo/efeitos dos fármacos , Hipocampo/fisiopatologia , Abuso de Maconha/fisiopatologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
16.
Pharmacogenomics J ; 12(4): 312-8, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21383771

RESUMO

Genetic markers displaying highly significant statistical associations with complex phenotypes may not necessarily possess sufficient clinical validity to be useful. Understanding the contribution of these markers beyond readily available clinical biomarkers is particularly important in pharmacogenetics. We demonstrate the utility of genetic testing using the example of warfarin in a multi-ethnic setting comprising of three Asian populations that are broadly representative of the genetic diversity for half of the population in the world, especially as distinct interethnic differences in warfarin dose requirements have been previously established. We confirmed the roles of three well-established loci (CYP2C9, VKORC1 and CYP4F2) in explaining warfarin dosage variation in the three Asian populations. In addition, we assessed the relationship between ethnicity and the genotypes of these loci, observing strong correlations at VKORC1 and CYP4F2. Subsequently, we established the additional utility of these genetic factors in predicting warfarin dose beyond ethnicity and clinical biomarkers through performing a series of systematic cross-validation analyses of the relative predictive accuracies of various fixed-dose regimen, clinical and genetic models. Through a pharmacogenetics model for warfarin, we show the importance of genetic testing beyond readily available clinical biomarkers in predicting dose requirements, confirming the role of genetic profiling in personalized medicine.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Oxigenases de Função Mista/genética , Farmacogenética/métodos , Hidrocarboneto de Aril Hidroxilases/genética , Povo Asiático/genética , China/etnologia , Família 4 do Citocromo P450 , Etnicidade/genética , Humanos , Índia/etnologia , Malásia/etnologia , Polimorfismo Genético , Medicina de Precisão/tendências , Singapura , Vitamina K Epóxido Redutases , Varfarina/administração & dosagem
17.
Artigo em Inglês | MEDLINE | ID: mdl-2540493

RESUMO

A P2 membrane preparation of rat brain (without cerebellum) was solubilized with CHAPS in Tris containing DTT and trypsin inhibitor. Two opiate ligands, 10b and 10cd, prepared by Liu et al, were employed consecutively in affinity chromatography, from which OPR's were eluted with Nx. The eluate was subsequently passed through a WGA affinity column and the OPR's eluted with N-GluNAc. This eluate was further purified and concentrated by preparative granular gel isoelectric focusing on SG200. Two protein peaks appeared separately at pH 5 and 7.8. The eluates from both peaks were examined for protein contents using the silver staining method, and binding activity was measured by RRA with 3H-etor. The results revealed that both samples contained active OPR purified to over 80,000 fold. The Mr was estimated by gel filtration to be 52 kD and 42 kD for OPR in the pH 5 and pH 7.8 samples respectively. OPR in the pH 5 sample have been determined to be of mu-type by their binding activity with 3H-ohm.


Assuntos
Química Encefálica , Receptores Opioides/isolamento & purificação , Animais , Membrana Celular/análise , Detergentes , Ratos , Receptores Opioides/metabolismo , Solubilidade , Membranas Sinápticas/análise
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