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1.
Mol Psychiatry ; 20(9): 1037-45, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26077693

RESUMO

Neuronal polarity and spatial rearrangement of neuronal processes are central to the development of all mature nervous systems. Recent studies have highlighted the dynamic expression of Collapsin-Response-Mediator Proteins (CRMPs) in neuronal dendritic/axonal compartments, described their interaction with cytoskeleton proteins, identified their ability to activate L- and N-type voltage-gated calcium channels (VGCCs) and delineated their crucial role as signaling molecules essential for neuron differentiation and neural network development and maintenance. In addition, evidence obtained from genome-wide/genetic linkage/proteomic/translational approaches revealed that CRMP expression is altered in human pathologies including mental (schizophrenia and mood disorders) and neurological (Alzheimer's, prion encephalopathy, epilepsy and others) disorders. Changes in CRMPs levels have been observed after psychotropic treatments, and disrupting CRMP2 binding to calcium channels blocked neuropathic pain. These observations, altogether with those obtained from genetically modified mice targeting individual CRMPs and RNA interference approaches, pave the way for considering CRMPs as potential early disease markers and modulation of their activity as therapeutic strategy for disorders associated with neurite abnormalities.


Assuntos
Doenças do Sistema Nervoso Central/patologia , Dendritos/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Neurônios/fisiologia , Animais , Dendritos/genética , Dendritos/metabolismo , Estudos de Associação Genética , Humanos , Camundongos , Morfogênese , Neurogênese , Neurônios/citologia , Neurônios/metabolismo , Neurônios/patologia
2.
Int J Tuberc Lung Dis ; 28(6): 266-272, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822483

RESUMO

BACKGROUNDCurrent metrics for TB transmission include TB notifications, disease mortality, and prevalence surveys. These metrics are helpful to national TB programs to assess the burden of disease, but they do not directly measure incident infection in the community.METHODSTo estimate incidence of Mycobacterium tuberculosis infection in Kampala, Uganda, we performed a prospective cohort study between 2014 and 2017 which enrolled of 1,275 adult residents without signs of tuberculous infection (tuberculin skin test [TST] <5 mm and no signs of TB disease) and followed them for conversion of TST at 1 year.RESULTSDuring follow-up, 194 participants converted the TST and 158 converted by one year. The incidence density of TST conversion was 13.2 conversions/100 person-year (95% CI 11.6-15.1), which corresponds to an annual cumulative incidence of tuberculous infection of 12.4% (95% CI 10.7-14.3). Cumulative incidence was greater among older participants and among men. Among participants who reported prior exposure to TB cases, the cumulative risk was highest among those reporting exposure during follow-up.CONCLUSIONSThe high annual incidence of infection suggests that residents of Kampala have adequate contact for infection with undetected, infectious cases of TB as they go about their daily lives..


Assuntos
Teste Tuberculínico , Tuberculose , Humanos , Incidência , Masculino , Uganda/epidemiologia , Adulto , Feminino , Estudos Prospectivos , Tuberculose/epidemiologia , Adulto Jovem , Pessoa de Meia-Idade , Adolescente , Mycobacterium tuberculosis/isolamento & purificação , Prevalência , Doenças Endêmicas , Estudos de Coortes
3.
Eur Rev Med Pharmacol Sci ; 27(19): 9091-9100, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37843323

RESUMO

OBJECTIVE: Spondylolisthesis is one of the common causes of spinal pain. There is currently a lack of studies on the correlation between magnetic resonance imaging (MRI) and clinical symptoms of patients with spondylolisthesis. This study is aimed to find the correlation between clinical symptoms of L4/L5, L5/S1 lumbar spondylolisthesis, and imaging parameters on MRI. PATIENTS AND METHODS: A retrospective study on 100 patients who were diagnosed with lumbar spondylolisthesis at the L4/L5, L5/S1 levels from August 2022 to February 2023. Parameters on MRI are measured the cross-sectional area of the dural sac (DSA), the cross-sectional area of the spinal canal (SCA), the ligamentum flavum cross-sectional area (LFA), and ligamentum flavum thickness (LFT), anterior-posterior diameter (APD), sliding distance (SD) at the spondylolisthesis level. Clinical symptoms were investigated according to the Visual Analogue Scale (VAS) for grading of pain and the subjective disability was assessed by the Oswestry Disability Index (ODI). RESULTS: There was no statistically significant difference between SD, APD, SCA, DSA, LFA, and LFT between the mild and moderate pain VAS and severe pain VAS groups. No correlation was found between VAS and SD, APD, SCA, DSA, LFA, and LFT. There is a negative correlation between ODI and APD, SCA, and DSA. The statistically significant difference in APD, SCA, and DSA indexes in the two groups with mild/moderate disability (ODI ≤40%) and the group with severe disability (ODI >40%). CONCLUSIONS: A higher DSA and SCA, APD are associated with lower ODI. Decreased APD, SCA, and DSA are all suggestive of decreased spinal function. However, the MRI findings did not correlate with the patient's clinical pain level.


Assuntos
Dor Lombar , Fusão Vertebral , Espondilolistese , Humanos , Espondilolistese/diagnóstico por imagem , Estudos Retrospectivos , Vértebras Lombares/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Fusão Vertebral/métodos , Resultado do Tratamento
4.
J Pain Symptom Manage ; 66(2): 146-159, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37088114

RESUMO

CONTEXT: Palliative care remains largely inaccessible in low- and middle-income countries (LMICs), and efforts to increase access are impeded by lack of training of proven effectiveness for physicians. OBJECTIVES: To measure the effectiveness of palliative care training for Vietnamese physicians. METHODS: The palliative care-related knowledge, attitudes, and self-assessment of Vietnamese physicians were studied prior to a basic course in palliative care (baseline), just after the physicians completed the course (post), and 6-18 months later (follow-up). RESULTS: The self-assessment scores and knowledge scores increased significantly from baseline to post and decreased significantly from post to follow-up, but the follow-up scores remained significantly higher than baseline. There were significant interactions between changes over time of the knowledge scores and baseline age, degree, years of graduation, training, type of work, and whether participants had ever prescribed morphine for pain. Medically appropriate attitudes increased significantly from baseline to post and did not decrease significantly from post to follow-up. CONCLUSION: Our basic palliative care course in Vietnam resulted in significant and enduring improvements among physicians in palliative care-related knowledge, attitudes, and self-assessed competence. To respond to the enormous unmet need for palliative care in LMICs, primary care providers and physician-specialists in many fields, among others, should receive palliative care training of proven effectiveness, receive ongoing mentoring or refresher training, and be given the responsibility and opportunity to practice what they learn.


Assuntos
Cuidados Paliativos , Médicos , Humanos , Cuidados Paliativos/métodos , Vietnã , Conhecimentos, Atitudes e Prática em Saúde , Dor , Atitude do Pessoal de Saúde , Inquéritos e Questionários
6.
J Pain Symptom Manage ; 60(4): 754-764, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32387576

RESUMO

CONTEXT: The International Association for Hospice and Palliative Care developed a consensus-based definition of palliative care (PC) that focuses on the relief of serious health-related suffering, a concept put forward by the Lancet Commission Global Access to Palliative Care and Pain Relief. OBJECTIVE: The main objective of this article is to present the research behind the new definition. METHODS: The three-phased consensus process involved health care workers from countries in all income levels. In Phase 1, 38 PC experts evaluated the components of the World Health Organization definition and suggested new/revised ones. In Phase 2, 412 International Association for Hospice and Palliative Care members in 88 countries expressed their level of agreement with the suggested components. In Phase 3, using results from Phase 2, the expert panel developed the definition. RESULTS: The consensus-based definition is as follows: Palliative care is the active holistic care of individuals across all ages with serious health-related suffering due to severe illness and especially of those near the end of life. It aims to improve the quality of life of patients, their families and their caregivers. The definition includes a number of bullet points with additional details as well as recommendations for governments to reduce barriers to PC. CONCLUSION: Participants had significantly different perceptions and interpretations of PC. The greatest challenge faced by the core group was trying to find a middle ground between those who think that PC is the relief of all suffering and those who believe that PC describes the care of those with a very limited remaining life span.


Assuntos
Cuidados Paliativos na Terminalidade da Vida , Enfermagem de Cuidados Paliativos na Terminalidade da Vida , Consenso , Humanos , Cuidados Paliativos , Qualidade de Vida
7.
Cytogenet Genome Res ; 126(3): 271-80, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20068298

RESUMO

Chromosome abnormalities are well known for their negative impact on the reproductive performance of carriers. Such abnormalities could have severe effect on animal industries which rely heavily on efficient reproduction. We conducted a cytogenetic survey of breeder pigs from 4 different Canadian farms to investigate the frequency of chromosome abnormalities and to assess their reproductive impact on pig populations. Our study revealed that 50% of the 'hypoprolific' boars and 2.5% of the young boars raised for service in artificial insemination were carriers of chromosome anomalies while no chromosome defect was noted in any of the 'proven' breeder boars. G-banding technique to determine the type of abnormalities detected 3 previously unreported translocations involving chromosomes 1 and 6, chromosomes 10 and 13 and chromosomes 9 and 14. The reciprocal nature of these translocations was confirmed either using fluorescent in situ hybridization (FISH) technique or immunostaining for synaptonemal complex delineation and were named rcp(1;6)(p22,q12), rcp(10;13), and rcp(9;14) (p24;q27), respectively. Prolificacy of 1/6 and 10/13 translocation carriers was noted to be reduced by more than 40% compared to their normal counterparts while it was reduced by 26% in carriers of the 9/14 translocation. Carriers of 1/6 and 9/14 translocations displayed a higher repeat breeding tendency, compared to their herd average (5 and 16%, respectively). While for the 9/14 translocation the prevalence of stillbirths was lower than that in their herd [8.7 vs. 10.4% (p < 0.001)]. The present results, albeit based on a relatively small number of pigs, indicate that the prevalence of chromosome abnormalities could be much higher in Canadian pigs compared to that reported in European pigs and underline the urgent need to initiate cytogenetic screening programs as one of the effective ways to reduce reproductive problems in Canadian pig populations.


Assuntos
Análise Citogenética/métodos , Suínos/genética , Animais , Cruzamento , Canadá , Bandeamento Cromossômico , Cromossomos de Mamíferos/genética , Feminino , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , Complexo Sinaptonêmico/metabolismo , Translocação Genética
8.
Int J Tuberc Lung Dis ; 22(9): 1000-1006, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30092864

RESUMO

OBJECTIVE: To investigate diagnostic agreement of the QuantiFERON®-TB Gold In-Tube (QFT-GIT) test in adult tuberculin skin test (TST) converters in a high tuberculosis (TB) burden setting. SETTING AND DESIGN: We performed a case-cohort study from 2014 to 2016 in Uganda among residents who were not infected with Mycobacterium tuberculosis. Participants were followed up for 1 year, when they were retested to determine TST conversion. All TST converters and a random sample of participants from baseline were offered QFT-GIT testing. RESULTS: Of 368 enrolled participants, 61 (17%) converted their TST by 1 year. Among 61 converters, 42 were tested using QFT-GIT, 64% of whom were QFT-GIT-positive. Of 307 participants with a persistent negative TST, 48 were tested using QFT-GIT, 83% of whom were QFT-negative. Overall concordance of TST and QFT-GIT was moderate (κ = 0.48, 95%CI 0.30-0.66). Converters with a conversion of 15 mm had a higher proportion of concordant QFT-GIT results (79%) than converters with increments of 10-14.9 mm (52%). CONCLUSION: Concordance between TST and QFT-GIT was moderate among TST converters in this urban African population. These findings call for improved tests that more accurately measure conversion to tuberculous infection.


Assuntos
Infecções por HIV/microbiologia , Testes de Liberação de Interferon-gama/métodos , Tuberculose/diagnóstico , Adolescente , Adulto , Contagem de Linfócito CD4 , Feminino , Infecções por HIV/complicações , Humanos , Masculino , Mycobacterium tuberculosis/imunologia , Estudos Prospectivos , Fatores de Risco , Teste Tuberculínico/métodos , Tuberculose/epidemiologia , Uganda/epidemiologia , Adulto Jovem
10.
Mol Cell Biol ; 18(12): 7590-601, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9819445

RESUMO

In the Saccharomyces cerevisiae Msh2p-Msh6p complex, mutations that were predicted to disrupt ATP binding, ATP hydrolysis, or both activities in each subunit were created. Mutations in either subunit resulted in a mismatch repair defect, and overexpression of either mutant subunit in a wild-type strain resulted in a dominant negative phenotype. Msh2p-Msh6p complexes bearing one or both mutant subunits were analyzed for binding to DNA containing base pair mismatches. None of the mutant complexes displayed a significant defect in mismatch binding; however, unlike wild-type protein, all mutant combinations continued to display mismatch binding specificity in the presence of ATP and did not display ATP-dependent conformational changes as measured by limited trypsin protease digestion. Both wild-type complex and complexes defective in the Msh2p ATPase displayed ATPase activities that were modulated by mismatch and homoduplex DNA substrates. Complexes defective in the Msh6p ATPase, however, displayed weak ATPase activities that were unaffected by the presence of DNA substrate. The results from these studies suggest that the Msh2p and Msh6p subunits of the Msh2p-Msh6p complex play important and coordinated roles in postmismatch recognition steps that involve ATP hydrolysis. Furthermore, our data support a model whereby Msh6p uses its ATP binding or hydrolysis activity to coordinate mismatch binding with additional mismatch repair components.


Assuntos
Adenosina Trifosfatases/metabolismo , Pareamento Incorreto de Bases/genética , Reparo do DNA/genética , Proteínas de Ligação a DNA/genética , Proteínas Fúngicas/genética , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Sequência de Aminoácidos , Ligação Competitiva , Proteínas de Ligação a DNA/metabolismo , Proteínas Fúngicas/metabolismo , Expressão Gênica/genética , Dados de Sequência Molecular , Proteína 2 Homóloga a MutS , Mutação/genética , Oligodesoxirribonucleotídeos/metabolismo , Fenótipo , Ligação Proteica , Conformação Proteica , Saccharomyces cerevisiae/metabolismo , Alinhamento de Sequência
11.
J Clin Endocrinol Metab ; 91(1): 105-14, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16263835

RESUMO

CONTEXT: Severe systemic infection leads to hypercortisolism. Reduced cortisol binding proteins may accentuate the free cortisol elevations seen in systemic infection. Recently, low total cortisol increments after tetracosactrin have been associated with increased mortality and hemodynamic responsiveness to exogenous hydrocortisone in septic shock (SS), a phenomenon termed by some investigators as relative adrenal insufficiency (RAI). HYPOTHESIS: Free plasma cortisol may correspond more closely to illness severity than total cortisol, comparing SS and sepsis (S). DESIGN: This was a prospective study. SETTING: This study took place in a tertiary teaching hospital. PATIENTS: Patients had SS (n = 45) or S (n = 19) or were healthy controls (HCs; n = 10). AIM: The aim of the study was to compare total with free cortisol, measured directly and estimated by Coolens' method, corticosteroid-binding globulin (CBG), and albumin in patients with SS (with and without RAI) and S during acute illness, recovery, and convalescence. RESULTS: Comparing SS, S, and HC subjects, free cortisol levels reflected illness severity more closely than total cortisol (basal free cortisol, SS, 186 vs. S, 29 vs. HC, 13 nmol/liter, P < 0.001 compared with basal total cortisol, SS, 880 vs. S, 417 vs. HC, 352 nmol/liter, P < 0.001). Stimulated free cortisol increments varied greatly with illness category (SS, 192 vs. S, 115 vs. HC, 59 nmol/liter, P = 0.004), whereas total cortisol increments did not (SS, 474 vs. S, 576 vs. HC, 524 nmol/liter, P = 0.013). The lack of increase in total cortisol with illness severity is due to lower CBG and albumin. One third of patients with SS (15 of 45) but no S patients met a recently described criterion for RAI (total cortisol increment after tetracosactrin < or = 248 nmol/liter). RAI patients had higher basal total cortisol (1157 vs. 756 nmol/liter; P = 0.028) and basal free cortisol (287 vs. 140 nmol/liter; P = 0.017) than non-RAI patients. Mean cortisol increments in RAI were lower (total, 99 vs. 648 nmol/liter, P < 0.001; free, 59 vs. 252 nmol/liter, P < 0.001). These differences were not due to altered CBG or albumin levels. Free cortisol levels normalized more promptly than total cortisol in convalescence. Calculated free cortisol by Coolens' method compared closely with measured free cortisol. CONCLUSIONS: Free cortisol is likely to be a better guide to cortisolemia in systemic infection because it corresponds more closely to illness severity. The attenuated cortisol increment after tetracosactrin in RAI is not due to low cortisol-binding proteins. Free cortisol levels can be determined reliably using total cortisol and CBG levels.


Assuntos
Hidrocortisona/sangue , Sepse/sangue , Choque Séptico/sangue , Insuficiência Adrenal/sangue , Insuficiência Adrenal/complicações , Idoso , Cosintropina , Feminino , Humanos , Masculino , Microdiálise , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Albumina Sérica/metabolismo , Transcortina/metabolismo
12.
J Neuropathol Exp Neurol ; 57(4): 311-22, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9600223

RESUMO

Paraneoplastic neurological diseases are disorders of the central nervous system, associated with neuronal degeneration in patients with systemic cancer, but are not a direct result of the tumor mass or metastasis. The biological diagnosis of these syndromes is based mainly on the detection, in the patient's serum and cerebrospinal fluid, of autoantibodies (anti-Hu, anti-Yo, for example), suggesting an autoimmune origin for these disorders. Recently, we described novel autoantibodies (anti-CV2 autoantibodies) associated with paraneoplastic neurological disease, which recognize a 66 kDa brain protein. We named this antigen POP66, for Paraneoplastic Oligodendrocyte Protein of 66 kDa molecular weight, as in the adult human, rat, and mouse brain, it is specifically expressed by a subpopulation of oligodendrocytes. This cell type specificity was surprising given the fact that the cell loss in the brains of patients with anti-CV2 autoantibodies is neuronal. POP66-expressing oligodendrocytes are distributed along the longitudinal axis of the brain according to an increasing rostro-caudal gradient, with no positive oligodendrocytes being found in the forebrain and the greatest number found in the spinal cord. In addition, in transverse sections of the spinal cord, the distribution of POP66-positive oligodendrocytes follows an increasing dorsal-to-ventral gradient, which may be related to different oligodendrocyte precursor pools. In addition, the neuronal loss without demyelination seen in the brains of patients with anti-CV2 autoantibodies, together with the exclusive oligodendroglial expression of POP66 in the adult brain, raises the question of the possible involvement of POP66 in neuron survival via neuron/oligodendrocyte interactions.


Assuntos
Antígenos de Neoplasias/imunologia , Neoplasias Encefálicas/imunologia , Encefalomielite/imunologia , Proteínas do Tecido Nervoso/imunologia , Oligodendroglia/imunologia , Síndromes Paraneoplásicas/imunologia , Adulto , Animais , Autoanticorpos/análise , Biomarcadores Tumorais , Encéfalo/imunologia , Encefalomielite/patologia , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Peso Molecular , Oligodendroglia/patologia , Síndromes Paraneoplásicas/patologia , Ratos , Medula Espinal/imunologia
13.
Gene ; 242(1-2): 175-82, 2000 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-10721710

RESUMO

CRMPs (collapsin response mediator proteins)/ULIPs (unc-33-like proteins) are a family of intracytoplasmic proteins that are expressed mainly in the brain. The involvement of CRMP/ULIP members in neuronal differentiation, growth cone motility and axonal collapse has been suggested. We recently found that a member of this family, CRMP3/ULIP4, corresponds to POP66 (paraneoplastic oligodendrocyte protein of 66 kDa), a protein which may be associated with auto-immune induced-neuronal degeneration in paraneoplastic neurological syndromes. However, the physiological functions of these proteins remain to be elucidated. Further studies, including the generation of cell lines and of animals with modified/disrupted CRMP/ULIP gene expression, are necessary to explore the functions of this protein. We have cloned and determined the organization and chromosomal localization of the mouse gene encoding CRMP3/ULIP4. The gene is composed of 14 exons and spans more than 20 kb. We assigned the mouse CRMP3/ULIP4 gene to the distal end of chromosome 7. In mouse brain, in situ hybridization showed that CRMP3/ULIP4 mRNA is expressed mainly in the dentate gyrus of hippocampus, in the granular layers of cerebellum and in the inferior olive of the pons, the nucleus which controls movement and posture, and adjusts the major output of descending motor system.


Assuntos
Genes/genética , Proteínas do Tecido Nervoso/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Encéfalo/embriologia , Encéfalo/metabolismo , Mapeamento Cromossômico , Cromossomos/genética , Cruzamentos Genéticos , DNA/química , DNA/genética , Éxons , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Ligação Genética , Hibridização In Situ , Íntrons , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Muridae , Análise de Sequência de DNA
14.
J Comp Neurol ; 337(4): 640-54, 1993 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-7904615

RESUMO

Aromatic L-amino acid decarboxylase (AAAD) is the second enzyme in the sequence leading to the synthesis of catecholamines or serotonin. Antisense riboprobes for aromatic L-amino acid decarboxylase mRNA were used to map the gene in mouse brain by in situ hybridization. The substantia nigra, the ventral tegmental nucleus, the dorsal raphe nucleus, the locus coeruleus, and the olfactory bulb contained the highest signal for AAAD mRNA. After treatment with the dopaminergic neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), the signal disappeared in the substantia nigra, decreased somewhat in the ventral tegmental area, and remained unchanged in the dorsal raphe nucleus. Hypothalamic and cerebellar Purkinje neurons known to contain histidine decarboxylase or glutamic acid decarboxylase, respectively, were unlabeled by the probes. However, neurons in the deep layers of the frontal cortex, many thalamic nuclei, and the pyramidal neurons of the hippocampus were lightly to moderately labeled for mouse AAAD mRNA. The presence of AAAD message in these neurons suggests that the enzyme has functions other than that for the synthesis of the classical biogenic amine neurotransmitters.


Assuntos
Descarboxilases de Aminoácido-L-Aromático/metabolismo , Encéfalo/enzimologia , RNA Mensageiro/metabolismo , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/análogos & derivados , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Animais , Northern Blotting , Southern Blotting , Encéfalo/anatomia & histologia , Mapeamento Encefálico , Clonagem Molecular , Dopaminérgicos/farmacologia , Imuno-Histoquímica , Hibridização In Situ , Masculino , Camundongos , Sondas RNA
15.
Neuropharmacology ; 27(6): 629-35, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2843784

RESUMO

The subclass of beta-adrenergic receptors mediating glycogenolysis in slices from cerebral cortex of the mouse, incubated in the presence of [3H]glucose, was identified by comparing the relative potencies of agonists and the inhibition constants of antagonists to those found on reference systems. (+/-)Isoprenaline, (-)adrenaline and (-)noradrenaline produced a concentration-related glycogenolysis with Kact values of 2.2 x 10(-8) M, 2.8 x 10(-7) M and 3.6 x 10(-7) M, respectively. Zinterol, a selective beta 2-adrenergic agonist, did not produce any glycogenolytic response even in a large concentration. Salbutamol, a predominantly beta 2-adrenergic receptor agonist, elicited in a very large concentration (10(-4) M) less than 40% glycogenolysis, an effect which was not related to stimulation of beta-adrenergic receptors. The predominantly beta 1-adrenergic receptor antagonists, practolol and metoprolol shifted the concentration-response curve to noradrenaline to the right, with apparent Ki values of 8.0 x 10(-7) M and 7.6 x 10(-8) M, respectively, close to those reported in the rat heart. These various data indicate that the glycogenolytic response is selectively mediated by beta 1-adrenergic receptors. Under experimental conditions which were strictly identical to those used to measure glycogenolysis, a saturable binding of [3H]dihydroalprenolol to the slices occurred with Kd and Bmax values consistent with corresponding values on cell free preparations. Whereas the Ki values of antagonists were similar on the two systems, the Kact values of agonists on glycogenolysis were 10 times less than the Ki values for the binding of [3H]dihydroalprenolol. This suggests that the maximal glycogenolytic response is elicited for a partial receptor occupancy.


Assuntos
Córtex Cerebral/metabolismo , Glicogênio/metabolismo , Receptores Adrenérgicos beta/fisiologia , Animais , Córtex Cerebral/fisiologia , Di-Hidroalprenolol/metabolismo , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos , Ensaio Radioligante
16.
Int J Oncol ; 25(6): 1839-47, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15547725

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common malignancies in Southeast Asia. Hyperphosphorylation of retinoblastoma (pRB) by cyclin/CDKs in G1/S transition is required for its inactivation and cell cycle progression. In the present study, we report that phosphorylation of pRB at Ser780 and Ser795 was detected in 71% (33 of 46) and 63% (29 of 46) of HCCs examined respectively. pRB protein was undetectable in 13% (6 of 46) of HCCs examined. Phosphorylated pRB was localized in the nuclei of hepatocarcinoma cells. Benign hepatocytes exhibited very weakly or no nuclear staining for phosphorylated pRB. Over-expression of E2F-1, cyclin D1, Cdk-2, Cdk-4 and cyclin A was found in 64% (30 of 46), 43% (26 of 46), 28% (11 of 46), 71% (33 of 46) and 63% (29 of 46) of HCCs examined respectively and this was correlated with elevation of ERK. Treatment of HepG2 cells with MEK1/2 inhibitor U0126 resulted in cell cycle arrest, downregulation of cyclin D1 and Cdk-2 expression and inhibition of pRB phosphorylation at Ser780 and Ser795. Ectopic expression of activated MEK1 in HepG2 cells increased cyclin D1 and Cdk-2 expression, phosphorylation of pRB at Ser780 and Ser795, and percentage of cells in S phase. Our data indicate that activated ERK plays an important role in cyclin D1 and Cdk-2 expression and phosphorylation of pRB at Ser780 and Ser795 in liver cancer cells.


Assuntos
Quinases relacionadas a CDC2 e CDC28/biossíntese , Carcinoma Hepatocelular/patologia , Ciclina D1/biossíntese , MAP Quinases Reguladas por Sinal Extracelular/farmacologia , Neoplasias Hepáticas/patologia , Quinase 2 Dependente de Ciclina , Humanos , Fosforilação , Proteína do Retinoblastoma/metabolismo , Células Tumorais Cultivadas
17.
Brain Res Mol Brain Res ; 8(3): 227-33, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2170800

RESUMO

In order to assess changes in enkephalin release and biosynthesis, the levels of the tripeptide Tyr-Gly-Gly (YGG), a characteristic extracellular metabolite of enkephalins, and of the proenkephalin mRNA in mouse striatum were evaluated after a single administration of GABAergic agents. Significant and long-lasting decreases in steady state YGG levels were elicited by muscimol, a gamma-aminobutyric acid-A (GABAA) receptor agonist, diazepam, a benzodiazepine receptor agonist, or aminooxyacetic acid, a GABA-transaminase inhibitor. In addition, muscimol offset the elevation of striatal YGG elicited by bestatin, an aminopeptidase inhibitor, which entirely drives the released enkephalins into the metabolic pathway operated by enkephalinase (EC 3.4.24.11). Diazepam potentiated the effect of muscimol so that the YGG decrease induced by the combination of these two drugs was maximal after 30 min (-60%) and still significant (-40%) after 6 h, this potentiation being antagonized by pre-treatment with Ro 15-1788, a specific benzodiazepine receptor antagonist. By contrast [Met5]enkephalin steady-state levels were marginally affected by GABAergic agents, being only slightly reduced 6 h after the combination of muscimol and diazepam. After 3 h the same treatment also reduced by about 30% the level of proenkephalin mRNA, this change being maximal after 6 h (-45%) and still present after 24 h. These compared changes in various indexes of enkephalin neuron activity suggest that stimulation of GABAA receptors depresses enkephalin release immediately and for several hours, whereas preproenkephalin gene expression is decreased in a somewhat delayed and longer lasting manner. These patterns of temporal changes in biosynthesis and release of the neuropeptide presumably account for the limited changes in its steady state levels.


Assuntos
Ácido Amino-Oxiacético/farmacologia , Corpo Estriado/metabolismo , Diazepam/farmacologia , Encefalinas/biossíntese , Encefalinas/genética , Oligopeptídeos/metabolismo , Precursores de Proteínas/genética , RNA Mensageiro/metabolismo , Receptores de GABA-A/fisiologia , Animais , Corpo Estriado/efeitos dos fármacos , Flumazenil/farmacologia , Cinética , Leucina/análogos & derivados , Leucina/farmacologia , Masculino , Camundongos , Muscimol/farmacologia , RNA Mensageiro/efeitos dos fármacos , Receptores de GABA-A/efeitos dos fármacos
18.
Brain Res Mol Brain Res ; 8(3): 235-41, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2170801

RESUMO

Injury to the cerebral cortex of the rat brain has been shown to induce the expression of neurotrophic factors for dissociated peripheral and central neurons in culture. We confirm this phenomenon and report that Xenopus laevis oocytes injected with mRNA extracted from wounded rat cortex expressed similar neurotrophic activity. To detect the low amounts of neurotrophic factors that could be expected from the oocyte translation system, a miniaturization of the assay for neurotrophic and cell-surviving activity was developed using Terasaki microtiter plates for culture of chicken embryo sympathetic ganglion cells. Messenger RNA (mRNA) was size-fractionated on a sucrose gradient and RNAs from each fraction were injected into oocytes. Neurotrophic activity was recovered from the homogenates and from the incubation media of oocytes injected with mRNA from 7 day post-lesion cortex. Messenger RNAs in the active fractions ranged in size from 0.8 to 1.8 kb. As much as 20% of the activity was secreted by the oocytes. No significant neurotrophic activity was detected from oocytes injected with mRNA fractions extracted from the cortex of control rats or from other gradient fractions from post-lesion cortex.


Assuntos
Córtex Cerebral/lesões , Gânglios Espinais/citologia , Gânglios Simpáticos/citologia , Oócitos/metabolismo , RNA Mensageiro/genética , Animais , Sobrevivência Celular , Células Cultivadas , Córtex Cerebral/metabolismo , Embrião de Galinha , Feminino , Microinjeções , Fatores de Crescimento Neural/análise , RNA Mensageiro/administração & dosagem , Ratos , Ratos Endogâmicos , Xenopus laevis
19.
Brain Res Mol Brain Res ; 46(1-2): 329-32, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9191111

RESUMO

Anti-CV2-autoantibodies from patients with paraneoplastic neurological syndromes were used to purify protein(s) related to this disease. A novel cDNA, c-22, was obtained by PCR with primers based on amino-acid sequence of peptides obtained from this protein and rat brain cDNA as template. The deduced amino-acid sequence of c-22 shows homology to the Unc-33 gene from C. elegans in which mutations lead to defects in neuritic outgrowth and axonal guidance and cause uncoordinated movements of the nematode. Several consensus sites for putative protein kinase C phosphorylation were found, suggesting that the c-22 gene product may be a phosphoprotein. Northern hybridizations show that the apparently unique 3.8-kb mRNA of c-22 is present in rat brain tissue and its expression is developmentally regulated: the levels of C-22 mRNA, detectable in brain at embryonic day 17 (E17), increase up to post-natal day 7 (P7) and decline rapidly to an almost undetectable level in adult.


Assuntos
Neoplasias Encefálicas/genética , Encéfalo/metabolismo , Proteínas de Caenorhabditis elegans , Clonagem Molecular , Proteínas de Helminto/genética , Fatores de Crescimento Neural/genética , Síndromes Paraneoplásicas/genética , Sequência de Aminoácidos , Animais , DNA Complementar/genética , Humanos , Dados de Sequência Molecular , Ratos
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