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1.
Mol Psychiatry ; 20(2): 193-200, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25600108

RESUMO

The µ-opioid receptor (MOR) system, well known for dampening physical pain, is also hypothesized to dampen 'social pain.' We used positron emission tomography scanning with the selective MOR radioligand [(11)C]carfentanil to test the hypothesis that MOR system activation (reflecting endogenous opioid release) in response to social rejection and acceptance is altered in medication-free patients diagnosed with current major depressive disorder (MDD, n=17) compared with healthy controls (HCs, n=18). During rejection, MDD patients showed reduced endogenous opioid release in brain regions regulating stress, mood and motivation, and slower emotional recovery compared with HCs. During acceptance, only HCs showed increased social motivation, which was positively correlated with endogenous opioid release in the nucleus accumbens, a reward structure. Altered endogenous opioid activity in MDD may hinder emotional recovery from negative social interactions and decrease pleasure derived from positive interactions. Both effects may reinforce depression, trigger relapse and contribute to poor treatment outcomes.


Assuntos
Encéfalo/metabolismo , Transtorno Depressivo Maior/patologia , Transtorno Depressivo Maior/psicologia , Distância Psicológica , Receptores Opioides mu/metabolismo , Facilitação Social , Adulto , Analgésicos Opioides/farmacocinética , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Radioisótopos de Carbono/farmacocinética , Emoções , Retroalimentação , Feminino , Fentanila/análogos & derivados , Fentanila/farmacocinética , Humanos , Hidrocortisona/sangue , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Tomografia por Emissão de Pósitrons , Ligação Proteica/efeitos dos fármacos , Escalas de Graduação Psiquiátrica , Radiografia , Adulto Jovem
2.
Mol Psychiatry ; 18(11): 1211-7, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23958960

RESUMO

The endogenous opioid system, which alleviates physical pain, is also known to regulate social distress and reward in animal models. To test this hypothesis in humans (n=18), we used an µ-opioid receptor (MOR) radiotracer to measure changes in MOR availability in vivo with positron emission tomography during social rejection (not being liked by others) and acceptance (being liked by others). Social rejection significantly activated the MOR system (i.e., reduced receptor availability relative to baseline) in the ventral striatum, amygdala, midline thalamus and periaqueductal gray (PAG). This pattern of activation is consistent with the hypothesis that the endogenous opioids have a role in reducing the experience of social pain. Greater trait resiliency was positively correlated with MOR activation during rejection in the amygdala, PAG and subgenual anterior cingulate cortex (sgACC), suggesting that MOR activation in these areas is protective or adaptive. In addition, MOR activation in the pregenual ACC was correlated with reduced negative affect during rejection. In contrast, social acceptance resulted in MOR activation in the amygdala and anterior insula, and MOR deactivation in the midline thalamus and sgACC. In the left ventral striatum, MOR activation during acceptance predicted a greater desire for social interaction, suggesting a role for the MOR system in social reward. The ventral striatum, amygdala, midline thalamus, PAG, anterior insula and ACC are rich in MORs and comprise a pathway by which social cues may influence mood and motivation. MOR regulation of this pathway may preserve and promote emotional well being in the social environment.


Assuntos
Encéfalo/metabolismo , Voluntários Saudáveis/psicologia , Distância Psicológica , Receptores Opioides mu/metabolismo , Adaptação Psicológica , Adulto , Afeto , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Feminino , Fentanila/análogos & derivados , Humanos , Masculino , Cintilografia
3.
Data Brief ; 54: 110365, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38646190

RESUMO

Although electroconvulsive therapy (ECT) is one of the most effective treatments for severe mood and psychotic disorders, the mechanisms underlying its therapeutic effects remain unknown. Electroconvulsive stimulation (ECS), the animal model for ECT, can be used to investigate the potential therapeutic mechanisms of ECT in rodents. ECS produces numerous effects in the brain, such as increasing levels of growth factors, inducing dendritic sprouting, and stimulating neurogenesis. It also induces high-level expression of immediate early genes (IEGs) that have been implicated in the pathogenesis of schizophrenia, such as early growth response 3 (Egr3) and activity-regulated cytoskeleton-associated protein (Arc), a validated downstream target of Egr3 [1-3]. However, the effect of isoflurane anesthesia preceding ECS on IEG response in mice has not been well characterized. This article provides immunofluorescent data of the activity responsive IEG ARC in the dorsal and ventral dentate gyrus of wildtype (WT) mice following ECS with or without anesthesia, as well as following sham ECS. The data in this article relate to a published article that employed serial ECS in mice to investigate the requirement of Egr3 in the neurobiological effects of this model of ECT [4]. The ability to study the effects of serial ECS has been limited in mice due to high rates of mortality during seizure. Administration of isoflurane anesthesia prior to ECS significantly reduces rodent mortality, irrespective of the number of times ECS is applied [5]. Since general anesthesia is administered to patients prior to ECT, use of isoflurane prior to ECS also more closely models the clinical use of ECT [6].

4.
BJOG ; 120(10): 1207-14, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23121042

RESUMO

OBJECTIVE: To document the rates of abortion among women diagnosed with HIV during pregnancy in two regions of China, and to investigate the sociodemographic factors associated with women's decisions to terminate their pregnancy. DESIGN: Prospective cohort study. SETTING: Three central Chinese provinces (Hubei, Hebei and Shanxi) and Yining, Xinjiang. POPULATION: Women diagnosed with HIV during pregnancy, 2004-2010. METHODS: Of 798 HIV-infected pregnant women identified through routine screening of pregnant women via antenatal care between 2004 and 2010, 499 women made decisions about the outcome of pregnancy. Chi-squared test was used to describe the characteristics of women who chose to terminate their pregnancies. Logistic regression models were used to identify potential predictors for pregnancy outcome for one cohort of women in central China and a second cohort of women in Yining, Xinjiang. MAIN OUTCOME MEASURES: Pregnancy outcome, trends of elective pregnancy termination. RESULTS: In the central China cohort, 76 of 161 pregnancies (47.2%) were terminated. In Yining, the proportion was significantly less, at only 61 of 338 (18.0%). Factors associated with pregnancy termination included unmarried marital status, already having one or more children and earlier trimester of pregnancy at the time of diagnosis. CONCLUSIONS: The rate of pregnancy termination in these cohorts of HIV-infected women appears to be higher than the rate in the general population of women in China. More work needs to be carried out to decrease the social stigma related to HIV and to convey clear messages about the effectiveness of prevention of mother to child transmission to women and their families. The significantly lower rate of pregnancy termination in Yining relative to central China is probably a result of the cultural and religious reservations towards pregnancy termination. Healthcare workers providing services to HIV-infected pregnant women need to be sensitive to cultural factors influencing women's decisions with regard to pregnancy termination.


Assuntos
Aborto Induzido/estatística & dados numéricos , Infecções por HIV/diagnóstico , Complicações Infecciosas na Gravidez/diagnóstico , Aborto Induzido/tendências , Adulto , Distribuição de Qui-Quadrado , China , Tomada de Decisões , Etnicidade/estatística & dados numéricos , Características da Família , Feminino , Idade Gestacional , Humanos , Modelos Logísticos , Estado Civil/estatística & dados numéricos , Gravidez , Complicações Infecciosas na Gravidez/virologia , Estudos Prospectivos , Fatores de Risco
5.
Nat Genet ; 14(1): 50-4, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8782819

RESUMO

MITF (microphthalmia-associated transcription factor) encodes a transcription factor with a basic-helix-loop-helix-zipper (bHLH-Zip) motif. MITF mutations occur in patients with Waardenburg syndrome type 2, a disorder associated with melanocyte abnormalities. Here we show that ectopic expression of MITF converts NIH/3T3 fibroblasts into cells with characteristics of melanocytes. MITF transfectants formed foci of morphologically altered cells, which resemble those induced by oncogenes, but did not exhibit malignant phenotypes. Instead, they contained dendritic cells that express melanogenic marker proteins such as tyrosinase and tyrosinase-related protein 1. Most cloned cells of MITF transfectants exhibited dendritic morphology and expressed melanogenic markers, but such properties were not observed in cells transfected with closely related TFE3 cDNA. Our findings indicate that MITF is critically involved in melanocyte differentiation.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Melanócitos/citologia , Fatores de Transcrição/fisiologia , Síndrome de Waardenburg/genética , Células 3T3 , Animais , Sequência de Bases , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Biomarcadores , Diferenciação Celular/genética , Primers do DNA , Proteínas de Ligação a DNA/genética , Expressão Gênica , Humanos , Camundongos , Fator de Transcrição Associado à Microftalmia , Dados de Sequência Molecular , Monofenol Mono-Oxigenase/genética , RNA , Fatores de Transcrição/genética , Transfecção
6.
Brain Stimul ; 16(3): 889-900, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37146791

RESUMO

BACKGROUND: Despite being one of the safest, most effective treatments for severe mood disorders, the therapeutic mechanisms of electroconvulsive therapy remain unknown. Electroconvulsive seizure (ECS) induces rapid, high-level expression of immediate early genes (IEGs) and brain-derived neurotrophic factor (BDNF), in addition to stimulation of neurogenesis and dendritic remodeling of dentate gyrus (DG) neurons. We have previously shown that this upregulation of BDNF fails to occur in the hippocampus of mice lacking the IEG Egr3. Since BDNF influences neurogenesis and dendritic remodeling, we hypothesized that Egr3-/- mice will exhibit deficits in neurogenesis and dendritic remodeling in response to ECS. OBJECTIVE: To test this hypothesis, we examined dendritic remodeling and cellular proliferation in the DG of Egr3-/- and wild-type mice following repeated ECS. METHODS: Mice received 10 daily ECSs. Dendritic morphology was examined in Golgi-Cox-stained tissue and cellular proliferation was analyzed through bromodeoxyuridine (BrdU) immunohistochemistry and confocal imaging. RESULTS: Serial ECS in mice results in dendritic remodeling, increased spine density, and cellular proliferation in the DG. Loss of Egr3 alters the dendritic remodeling induced by serial ECS but does not change the number of dendritic spines or cellular proliferation consequences of ECS. CONCLUSION: Egr3 influences the dendritic remodeling induced by ECS but is not required for ECS-induced proliferation of hippocampal DG cells.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Hipocampo , Camundongos , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Hipocampo/fisiologia , Convulsões/metabolismo , Proliferação de Células , Neurogênese/fisiologia , Giro Denteado/fisiologia
7.
Am J Transplant ; 12(12): 3449-61, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22994804

RESUMO

In a cross-sectional study, we assessed effects of calcineurin inhibitor (CNI) or rapamycin on T-regulatory (Treg) cells from children with stable liver (n = 53) or kidney (n = 9) allografts several years posttransplant. We analyzed Treg number, phenotype, suppressive function, and methylation at the Treg-specific demethylation region (TSDR) using Tregs and peripheral blood mononuclear cells. Forty-eight patients received CNI (39 as monotherapy) and 12 patients received rapamycin (9 as monotherapy). Treg numbers diminished over time on either regimen, but reached significance only with CNI (r =-0.424, p = 0.017). CNI levels inversely correlated with Treg number (r =-0.371, p = 0.026), and positively correlated with CD127+ expression by Tregs (r = 0.437, p = 0.023). Patients with CNI levels >3.6 ng/mL had weaker Treg function than those with levels <3.6 ng/mL, whereas rapamycin therapy positively correlated with Treg numbers (r = 0.628, p = 0.029) and their expression of CTLA4 (r = 0.726, p = 0.041). Overall, CTLA4 expression, TSDR demethylation and an absence of CD127 were important for Treg suppressive function. We conclude that rapamycin has beneficial effects on Treg biology, whereas long-term and high dose CNI use may impair Treg number, function and phenotype, potentially acting as a barrier to attaining host hyporesponsiveness to an allograft.


Assuntos
Calcineurina/uso terapêutico , Rejeição de Enxerto/imunologia , Imunossupressores/uso terapêutico , Transplante de Rim/imunologia , Transplante de Fígado/imunologia , Sirolimo/uso terapêutico , Linfócitos T Reguladores/efeitos dos fármacos , Adolescente , Estudos de Casos e Controles , Criança , Estudos Transversais , Feminino , Seguimentos , Fatores de Transcrição Forkhead/metabolismo , Humanos , Leucócitos Mononucleares/imunologia , Masculino , Prognóstico , Linfócitos T Reguladores/imunologia , Transplante Homólogo
8.
Photosynth Res ; 113(1-3): 321-33, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22711426

RESUMO

Green leaf volatiles (GLVs) are a diverse group of fatty acid-derived compounds emitted by all plants and are involved in a wide variety of developmental and stress-related biological functions. Recently, GLV emission bursts from leaves were reported following light-dark transitions and hypothesized to be related to the stress response while acetaldehyde bursts were hypothesized to be due to the 'pyruvate overflow' mechanism. In this study, branch emissions of GLVs and a group of oxygenated metabolites (acetaldehyde, ethanol, acetic acid, and acetone) derived from the pyruvate dehydrogenase (PDH) bypass pathway were quantified from mesquite plants following light-dark transitions using a coupled GC-MS, PTR-MS, and photosynthesis system. Within the first minute after darkening following a light period, large emission bursts of both C(5) and C(6) GLVs dominated by (Z)-3-hexen-1-yl acetate together with the PDH bypass metabolites are reported for the first time. We found that branches exposed to CO(2)-free air lacked significant GLV and PDH bypass bursts while O(2)-free atmospheres eliminated the GLV burst but stimulated the PDH bypass burst. A positive relationship was observed between photosynthetic activity prior to darkening and the magnitude of the GLV and PDH bursts. Photosynthesis under (13)CO(2) resulted in bursts with extensive labeling of acetaldehyde, ethanol, and the acetate but not the C(6)-alcohol moiety of (Z)-3-hexen-1-yl acetate. Our observations are consistent with (1) the "pyruvate overflow" mechanism with a fast turnover time (<1 h) as part of the PDH bypass pathway, which may contribute to the acetyl-CoA used for the acetate moiety of (Z)-3-hexen-1-yl acetate, and (2) a pool of fatty acids with a slow turnover time (>3 h) responsible for the C(6) alcohol moiety of (Z)-3-hexen-1-yl acetate via the 13-lipoxygenase pathway. We conclude that our non-invasive method may provide a new valuable in vivo tool for studies of acetyl-CoA and fatty acid metabolism in plants at a variety of spatial scales.


Assuntos
Luz , Metaboloma , Oxigênio/metabolismo , Folhas de Planta/metabolismo , Caules de Planta/metabolismo , Prosopis/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Escuridão , Cromatografia Gasosa-Espectrometria de Massas , Metaboloma/efeitos da radiação , Folhas de Planta/efeitos da radiação , Caules de Planta/efeitos da radiação , Prosopis/efeitos da radiação , Prótons , Complexo Piruvato Desidrogenase/metabolismo , Fatores de Tempo
9.
J Cell Biol ; 127(2): 479-87, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7929590

RESUMO

The tyrosine phosphorylation sites in the human alpha PDGF receptor (alpha PDGFR) required for association with PI-3 kinase have been identified as tyrosines 731 and 742. Mutation of either tyrosine substantially reduced PDGF-induced PI-3 kinase activity but did not impair the receptor-mediated mitogenic response. We sought to determine whether PDGF-induced PI-3 kinase activity could be further ablated so as to exclude a low threshold requirement for PDGFR signal transduction. Thus, we mutated both tyrosine 731 and 742 and expressed the double mutant (Y731F/Y742F) in 32D hematopoietic cells. In such transfectants, PDGF induced no detectable receptor-associated or anti-P-Tyr recoverable PI-3 kinase activity. Under the same conditions, neither mobility shift of raf-1 nor tyrosine phosphorylation of either PLC gamma or MAP kinase was impaired. 32D transfectants expressing the double mutant showed wild-type alpha PDGFR levels of mitogenic and chemotactic responses to PDGF. To examine the effect of the double mutation in cells that normally respond to PDGF, we generated chimeras in which the cytoplasmic domains of wild-type alpha PDGFR, Y731F, and Y731F/Y742F were linked to the extracellular domain of colony-stimulating factor-1 (CSF-1) receptor (fms). After introduction of the chimeric receptors into mouse NIH/3T3 fibroblasts, the ability of CSF-1 to stimulate growth of these transfectants was examined. Our data show that all these chimeric receptors exhibited similar abilities to mediate CSF-1-stimulated cell growth. These findings lead us to conclude that PDGF-induced PI-3 kinase activity is not required for PDGF-stimulated mitogenic pathway in both NIH/3T3 fibroblasts and 32D hematopoietic cells.


Assuntos
Divisão Celular , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Fator de Crescimento Derivado de Plaquetas/farmacologia , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais , Células 3T3 , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Transformação Celular Neoplásica , Quimiotaxia , Ativação Enzimática , Indução Enzimática , Camundongos , Proteína Quinase 1 Ativada por Mitógeno , Dados de Sequência Molecular , Mutação , Fosfatidilinositol 3-Quinases , Fosfatos de Fosfatidilinositol/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-raf , Receptores do Fator de Crescimento Derivado de Plaquetas/genética , Proteínas Recombinantes de Fusão/farmacologia , Transfecção , Fosfolipases Tipo C/metabolismo
11.
Science ; 286(5447): 2176-9, 1999 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-10591653

RESUMO

Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder characterized by increased incidence of benign and malignant tumors of neural crest origin. Mutations that activate the protooncogene ras, such as loss of Nf1, cooperate with inactivating mutations at the p53 tumor suppressor gene during malignant transformation. One hundred percent of mice harboring null Nf1 and p53 alleles in cis synergize to develop soft tissue sarcomas between 3 and 7 months of age. These sarcomas exhibit loss of heterozygosity at both gene loci and express phenotypic traits characteristic of neural crest derivatives and human NF1 malignancies.


Assuntos
Modelos Animais de Doenças , Genes da Neurofibromatose 1 , Genes p53 , Neurofibromatose 1/genética , Neurofibromatose 1/patologia , Sarcoma/patologia , Animais , Biomarcadores Tumorais , Diferenciação Celular , Transformação Celular Neoplásica , Cruzamentos Genéticos , Feminino , Heterozigoto , Humanos , Perda de Heterozigosidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Crista Neural/metabolismo , Crista Neural/patologia , Sarcoma/genética , Células de Schwann/metabolismo , Células de Schwann/patologia , Células Tumorais Cultivadas
12.
J Nutr Health Aging ; 21(7): 772-780, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28717807

RESUMO

OBJECTIVES: Vitamin D status has been hypothesized to protect against development of early age-related macular degeneration (AMD) via its anti-inflammatory properties and its possible beneficial influence on blood pressure control. We investigated the association between vitamin D status and prevalent early AMD in a community-based cohort. DESIGN: This was a cross-sectional study. SETTING: This was a secondary data analysis of already existing data from the Atherosclerosis Risk in Communities Study (ARIC) cohort collected from 1990 to 1995. PARTICIPANTS: There were 9,734 (7,779 Caucasians, 1,955 African American) ARIC participants (aged 46 to 70 at visit 2 [1990-1992]) with 25(OH)D data available at visit 2, AMD assessment at visit 3 (1993-1995), and complete covariate data. MEASUREMENTS: Vitamin D status was assessed with serum 25-hydroxyvitamin D (25(OH)D) concentrations from bloods drawn at visit 2. Prevalent, early AMD (n=511) was assessed at visit 3 (1993-95) with nonmydriatic retinal photographs of one randomly chosen eye. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for early AMD by categories of 25(OH)D in nmol/L (deficient <30, inadequate 30-<50, and two categories of adequate status: 50-<75 and ≥75). Linear trend was estimated using continuous 25(OH)D concentrations. ORs were adjusted for age, race, and smoking status. We further adjusted for hypertension status to examine if vitamin D status influenced early AMD via its effects on blood pressure. Exploratory analyses of effect modification by age, sex, race and high risk genotypes [Y402H complement factor H (CFH) rs1061170 and the A69S age-related maculopathy susceptibility 2 (ARMS2) rs10490924 polymorphisms] were conducted. RESULTS: The prevalence of early AMD was 5%, and 5% of participants were vitamin D deficient. The adjusted OR (95% CIs) for early AMD among those with adequate (≥75 nmol/L) compared to deficient (<30 nmol/L) vitamin D status was 0.94 (0.59-1.50), p-trend=0.86. Further adjustment for hypertension status did not influence results (OR [95% CI]=0.95 [0.59-1.52], p-trend=0.84). Results did not vary significantly by age, race, sex, early AMD subtype (soft drusen or retinal pigment epithelium depigmentation), or ARMS2 genotype. Results did not vary significantly by CFH genotype in African Americans. The p for multiplicative interaction between 25(OH)D and CFH genotype was 0.06 in Caucasians, but OR [95% CIs] for AMD by vitamin D status were similar in each CFH genotype and not statistically significant. CONCLUSIONS: Vitamin D status was not associated with early AMD in this cohort sample.


Assuntos
Aterosclerose/epidemiologia , Negro ou Afro-Americano , Degeneração Macular/epidemiologia , Vitamina D/sangue , População Branca , Aterosclerose/sangue , Biomarcadores/sangue , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Degeneração Macular/sangue , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Prevalência , Estudos Prospectivos , Fatores de Risco
13.
J Natl Cancer Inst ; 65(5): 929-35, 1980 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6933263

RESUMO

The role of natural killer (NK) cells in tumor growth and metastasis was studied in syngeneic normal and beige inbred C57BL/6 mice. Mice with the beige point mutation have been shown to be deficient in nonstimulated NK activity. Tumor-passaged B16 malignant melanoma cells were refractory to NK activity as determined by in vitro assay, but after in vitro culture they became sensitive to NK activity. The NK-insensitive B16 tumor grew and metastasized similarly in normal and beige mice. However, the NK-sensitive B16 tumors grew more slowly and produced fewer metastases in normal mice than in NK-deficient beige mice. Activation of NK cells by lymphocytic choriomeningitis virus infection decreased the rate of growth and number of metastases of both NK-sensitive and NK-insensitive tumors in both normal and beige mice. These results suggest the importance of NK cells as a determinant of tumor growth and metastasis.


Assuntos
Células Matadoras Naturais/imunologia , Melanoma/imunologia , Metástase Neoplásica , Animais , Células Cultivadas , Melanoma/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/fisiopatologia , Baço/imunologia
14.
Oncogene ; 18(12): 2055-68, 1999 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-10321730

RESUMO

Nerve growth factor induces differentiation and survival of rat PC12 pheochromocytoma cells. The activation of the erk cascade has been implicated in transducing the multitude of signals induced by NGF. In order to explore the role of this signaling cascade in NGF mediated survival, differentiation and proliferation, we generated recombinant adenoviruses which express the intermediates of the erk cascade in their wild type, dominant negative and constitutively activated forms. We show that differentiation of PC12 cells requires activity of the ras/erk pathway, whereas inhibition of this pathway had no effect on survival or proliferation. Constitutively active forms of ras, raf and mek induced PC12 cell differentiation, while dominant interfering forms inhibited differentiation. Survival of PC12 cells in serum-free medium did not require activity of the ras/erk pathway. Instead, PI3 Kinase signaling was necessary for PC12 cell survival. Interestingly, constitutively activated versions of raf and mek were able to promote survival, but again this was dependent on activation of PI3 Kinase. Therefore, at least two distinct signaling pathways are required in PC12 cells for mediation of NGF functions.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Fatores de Crescimento Neural/farmacologia , Neurônios/citologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Diferenciação Celular , Divisão Celular , Sobrevivência Celular , Células PC12 , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Ratos , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Sistema Nervoso Simpático/citologia
15.
Arch Intern Med ; 146(9): 1739-40, 1986 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3753114

RESUMO

Four elderly patients (71, 53, 57, and 62 years old) had disseminated gonococcal infection. Three patients presented with suppurative arthritis and the fourth with fever, skin lesions, and malaise. Although the signs and symptoms did not differ from those in the younger age group, the diagnosis was not considered clinically. All gonococci were susceptible to penicillin.


Assuntos
Artrite Infecciosa/etiologia , Gonorreia/diagnóstico , Fatores Etários , Idoso , Diagnóstico Diferencial , Feminino , Febre/etiologia , Gonorreia/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Penicilina G/uso terapêutico
16.
Exp Hematol ; 24(6): 696-701, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8635525

RESUMO

Canine idiopathic thrombocytopenic purpura (ITP) is clinically analogous to chronic ITP in human beings. The objective of this study was to investigate the pathogenesis of canine ITP by determining whether immunoglobulins bound to the surface of platelets from dogs with ITP (platelet-bound immunoglobulins) were directed against host platelet antigen and whether platelet glycoproteins (GP) IIb and IIIa were target antigens in dogs with ITP. Thirty-two dogs with ITP were studied. Increased platelet-bound immunoglobulin concentrations were detected in 30 cases (94%), and increased concentrations of serum platelet-bindable immunoglobulins were detected in 11 cases (34%). Immunoglobulins eluted from the surface of platelets from dogs with ITP bound to homologous normal canine platelets in 11 of 19 cases (58%). Immunoglobulins against platelet membrane GP IIb and/or IIIa were detected in serum from four of 17 affected dogs. This study provides evidence that immunoglobulins bound to surface of platelets from some dogs with ITP are directed against host platelet antigens and that platelet target antigens are, in some cases, GP IIb and IIIa. This supports the hypothesis that canine ITP is an autoimmune disease, similar to the pathogenesis of chronic ITP in human beings.


Assuntos
Plaquetas/imunologia , Glicoproteínas da Membrana de Plaquetas/imunologia , Púrpura Trombocitopênica Idiopática/veterinária , Animais , Autoanticorpos/imunologia , Autoantígenos/imunologia , Doenças do Cão/imunologia , Cães , Oxirredução , Contagem de Plaquetas , Púrpura Trombocitopênica Idiopática/imunologia
17.
Addict Behav ; 41: 210-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25452067

RESUMO

INTRODUCTION: Previous research has demonstrated that chronic cigarette smoking and major depressive disorder (MDD) are each associated with cognitive decrements. Further, these conditions co-occur commonly, though mechanisms in the comorbid condition are poorly understood. There may be distinct, additive, or overlapping factors underlying comorbid cigarette smoking and MDD. The present study investigated the impact of smoking and MDD on executive function and emotion processing. METHODS: Participants (N=198) were grouped by diagnostic category (MDD and healthy controls, HC) and smoking status (ever-smokers, ES and never-smokers, NS). Participants completed the Facial Emotion Perception Test (FEPT), a measure of emotional processing, and the parametric Go/No-go task (PGNG), a measure of executive function. RESULTS: FEPT performance was analyzed using ANCOVA with accuracy and reaction time as separate dependent variables. Repeated measures MANCOVA was conducted for PGNG with performance measure and task level as dependent variables. Analyses for each task included diagnostic and smoking group as independent variables, and gender was controlled for. Results for FEPT reveal that lower overall accuracy was found for ES relative to NS, though MDD did not differ from HC. Post-hoc analyses revealed that ES were poorer at identifying happy and sad, but not fearful or angry, faces. For PGNG, poorer performance was observed in MDD relative to HC in response time to Go targets, but there were no differences for ES and NS. Interaction of diagnosis and smoking group was not observed for performance on either task. CONCLUSIONS: The results of this study provide preliminary evidence for distinctive cognitive decrements in smokers and individuals with depression.


Assuntos
Transtorno Depressivo Maior/epidemiologia , Transtorno Depressivo Maior/psicologia , Expressão Facial , Felicidade , Fumar/epidemiologia , Percepção Visual/fisiologia , Adulto , Análise de Variância , Transtorno Depressivo Maior/fisiopatologia , Emoções , Feminino , Humanos , Masculino , Michigan/epidemiologia , Estudos Retrospectivos
18.
AIDS ; 9(1): 73-9, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7893444

RESUMO

OBJECTIVE: To examine long-term changes in psychological symptomatology from 6 to 24 months after notification of HIV serostatus among male injecting drug users (IDU). DESIGN: Self-report and interview data were collected at 6-month intervals as part of a longitudinal study monitoring HIV infection and risk-associated behaviors among IDU. SETTING: A community-based methadone-maintenance clinic. PARTICIPANTS: Ninety-seven male IDU (81 HIV-seronegative, 16 HIV-seropositive), including both methadone-maintained and out-of-treatment IDU. MAIN OUTCOME MEASURES: Analyses of long-term changes in psychological symptomatology associated with HIV serostatus among male IDU. RESULTS: Analyses of long-term changes in psychological symptomatology between groups revealed no significantly greater levels of overall psychological distress or significant elevations on subscales of the Symptom Checklist-90 for HIV-seropositive compared with HIV-seronegative male IDU. Also, no significantly higher scores on the Beck Depression Inventory or the psychiatric composite score of the Addiction Severity Index were observed between groups. CONCLUSIONS: Our results suggest that HIV-seropositive male IDU do not express greater levels of psychological symptomatology from 6 to 24 months following notification of seropositivity compared with HIV-seronegative male IDU. Several explanations for these findings are considered. Future work should examine why male IDU do not report significant and long-term elevations in symptoms post-notification of HIV seropositivity. Also, studies of changes in psychological symptomatology as a function of HIV serostatus among female IDU need to be conducted to assess implications for treatment interventions among this underserved population.


Assuntos
Soropositividade para HIV/psicologia , Abuso de Substâncias por Via Intravenosa/psicologia , Adulto , Anticorpos Anti-HIV/análise , Soronegatividade para HIV/imunologia , Soropositividade para HIV/imunologia , Humanos , Estudos Longitudinais , Masculino , Transtornos Mentais/diagnóstico , Escalas de Graduação Psiquiátrica , Estudos Soroepidemiológicos , Abuso de Substâncias por Via Intravenosa/imunologia
19.
Neurology ; 26(12): 1169-72, 1976 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1033485

RESUMO

The Chediak-Higashi syndrome is characterized by a serotonin platelet defect and neuronal dysfunction. Whole blood serotonin concentration, serotonin brain concentration, and synaptosomal uptake of serotonin were determined in mice with the syndrome. While brain serotonin uptake in the affected mice was not significantly different from that in nonaffected mice, whole blood serotonin concentration was markedly reduced. These data suggest that in human neuropathies with platelet serotonin defect, a parallel neuronal serotonin disorder may not be assumed.


Assuntos
Encéfalo/metabolismo , Síndrome de Chediak-Higashi/metabolismo , Serotonina/metabolismo , Sinaptossomos/metabolismo , Animais , Feminino , Masculino , Camundongos , Serotonina/sangue
20.
Neuropharmacology ; 22(6): 781-4, 1983 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6310435

RESUMO

The existence of high-affinity [3H]-imipramine recognition sites was demonstrated in membranes prepared from the cerebral cortex, hypothalamus and platelets obtained from fawn-hooded rats. The Bmax and Kd values for [3H]-imipramine binding to cerebral cortical membranes were virtually identical to those obtained with cortical membrane preparations of Sprague-Dawley rats. An NBR strain of rats, genetically related to fawn-hooded rats, was found to have significantly higher levels of [3H]-imipramine binding sites in cerebral cortical membranes when compared to fawn-hooded and Sprague-Dawley rats. All four strains of rats examined possessed extremely high densities of [3H]-imipramine binding sites in a purified platelet membrane fraction. These results do not support the finding of others that the cerebral cortex and platelets of fawn-hooded rats are virtually devoid of [3H]-imipramine binding sites.


Assuntos
Proteínas de Transporte , Córtex Cerebral/metabolismo , Hipotálamo/metabolismo , Imipramina/metabolismo , Receptores de Droga , Receptores de Neurotransmissores/metabolismo , Animais , Plaquetas/metabolismo , Membrana Celular/metabolismo , Cruzamentos Genéticos , Cinética , Ratos , Ratos Endogâmicos , Especificidade da Espécie , Trítio
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