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1.
Cancers (Basel) ; 15(8)2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37190220

RESUMO

Lymphomas related to HIV are generally aggressive and have a poor prognosis, despite the use of combined antiretroviral therapy (cART) and effective chemotherapy treatment. To determine survival and prognostic factors in children and adolescents living with HIV (CLWH) in Rio de Janeiro (RJ), Brazil, who developed lymphomas, we performed a retrospective and observational study of vertically infected CLWH aged from 0 to 20 incomplete years during1995 to 2018 at five reference centers for cancer and HIV/AIDS treatment. Of the 25 lymphomas, 19 were AIDS-defining malignancies (ADM) and 6 were non-AIDS-defining malignancies (NADM). The 5-year overall survival (OS) and 5-year event-free survival (EFS) probabilities were both 32.00% (95% CI = 13.72-50.23%), and the 5-year disease-free survival (DFS) probability was 53.30% (95% CI = 28.02-78.58%). In the multivariate Cox regression analysis, performance status 4 (PS 4) was considered a poor prognostic factor for OS (HR 4.85, 95% CI = 1.81-12.97, p = 0.002) and EFS (HR 4.95, 95% CI = 1.84-13.34, p = 0.002). For the DFS, higher CD4+ T-cell counts were considered a better prognostic factor (HR 0.86, 95% CI = 0.76-0.97, p = 0.017) in the multivariate Cox regression analysis. This study demonstrates, for the first time, survival and prognostic factors for CLWH who developed lymphomas in RJ, Brazil.

2.
Cancers (Basel) ; 14(24)2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36551614

RESUMO

The incidence of cancer in children living with HIV (CLWH) is high and lymphomas are the most common type of cancer in this population. The combined antiretroviral therapy (cART) changed the natural history of HIV infection. To determine the incidence and profile of these CLWH malignancies in Rio de Janeiro (RJ), Brazil, we conducted a retrospective and observational study of vertically infected CLWH, ranging from 0−20 incomplete years, from 1995 to 2018, at five reference centers. The study period was divided into three eras in accordance with the widespread use of cART in Brazil. 1306 patients were included. Of the 25 lymphomas found, 19 were AIDS-defining malignancies (ADM); 6 were non-AIDS-defining malignancies (NADM). The incidence rate (IR) of lymphoma developing was 1.70 per 1000 children-year (95% CI 1.09−2.50). ADM development IR decreased from 2.09−1.75−0.19 per 1000 children-year (p < 0.001) through cART eras. Cumulative Nelson−Aalen hazards of developing ADM over a 20-year period were 3.73% in the Early-cART era, 3.07% in the Mid-cART era, and 0.32% in the Late-cART era (p = 0.013). This study demonstrates the IR of lymphoma in CLWH in RJ, Brazil, as well as the benefit of cART in reducing ADM and death occurrence in the Post-cART era.

3.
J Hum Nutr Diet ; 33(5): 729-737, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32283572

RESUMO

INTRODUCTION: The BEVQ-15 is a beverage intake questionnaire that estimates the habitual average daily intake of 15 beverage categories (kcal and fl oz), as well as total sugar-sweetened beverages (SSB) and total beverages. However, subsequent to its initial validation in 2010, it has not been updated. The present study aimed to assess the convergent validity and reproducibility of the updated form of the BEVQ-15 to better reflect current beverage consumption trends. METHODS: The study population included adults (n = 50) aged ≥18 years, recruited from a local university community. Participation consisted of three laboratory visits within a 4-week period in which the updated BEVQ-15 was administered during the first and last visit and four 24-h dietary recalls were collected. BEVQ-15 modifications included removing limits of 60 fl oz per beverage, adding a nut milk category, and providing creamer and sweetener preferences for coffee/tea categories. Convergent validity was assessed by comparing reported beverage intake between the BEVQ-15 and dietary recalls. Reproducibility was assessed by comparing both BEVQ-15 administrations. Analyses included descriptive statistics, Wilcoxon signed rank tests, Bland-Altman plots and Spearman's correlations. RESULTS: For validity, Bland-Altman plot agreement between the BEVQ-15 and recalls was in the range 92-96% for total SSB and total beverage intake. For reproducibility, all beverage categories, total SSB, and total beverage intake were significantly correlated between the two BEVQ-15 administrations (r = 0.41-0.85; P ≤ 0.01). CONCLUSIONS: This updated version of the BEVQ-15 demonstrated moderate convergent validity and reproducibility for total beverage consumption among well-educated southwest Virginia adults.


Assuntos
Bebidas/análise , Inquéritos sobre Dietas/normas , Dieta/estatística & dados numéricos , Inquéritos e Questionários/normas , Adolescente , Adulto , Comportamento Alimentar , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Adulto Jovem
4.
J Thromb Haemost ; 15(3): 487-499, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28029716

RESUMO

Essentials Capnocytophaga canimorsus causes severe dog bite related blood stream infections. We investigated if C. canimorsus contributes to bleeding abnormalities during infection. The C. canimorsus protease CcDPP7 causes factor X dysfunction by N-terminal cleavage. CcDPP7 inhibits coagulation in vivo, which could promote immune evasion and trigger hemorrhage. SUMMARY: Background Capnocytophaga canimorsus is a Gram-negative bacterium that is present in the oral flora of dogs and causes fulminant sepsis in humans who have been bitten, licked, or scratched. In patients, bleeding abnormalities, such as petechiae, purpura fulminans, or disseminated intravascular coagulation (DIC), occur frequently. Objective To investigate whether C. canimorsus could actively contribute to these bleeding abnormalities. Methods Calibrated automated thrombogram and clotting time assays were performed to assess the anticoagulant activity of C. canimorsus 5 (Cc5), a strain isolated from a fatal human infection. Clotting factor activities were measured with factor-deficient plasma. Factor X cleavage was monitored with the radiolabeled zymogen and western blotting. Mutagenesis of Cc5 genes encoding putative serine proteases was performed to identify the protease that cleaves FX. Protein purification was performed with affinity chromatography. Edman degradation allowed the detection of N-terminal cleavage of FX. Tail bleeding times were measured in mice. Results We found that Cc5 inhibited thrombin generation and increased the prothrombin time and the activated partial thromboplastin time of human plasma via FX cleavage. A mutant that was unable to synthesize a type 7 dipeptidyl peptidase (DPP7) of the S46 serine protease family failed to proteolyse FX. The purified protease (CcDPP7) cleaved FX heavy and light chains from the N-terminus, and was active in vivo after intravenous injection. Conclusions This is, to our knowledge, the first study demonstrating a detailed mechanism for FX inactivation by a bacterial protease, and it is the first functional study associating DPP7 proteases with a potentially pathogenic outcome.


Assuntos
Mordeduras e Picadas/microbiologia , Capnocytophaga/enzimologia , Coagulação Intravascular Disseminada/microbiologia , Fator X/antagonistas & inibidores , Peptídeo Hidrolases/química , Animais , Catálise , Voluntários Saudáveis , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mutação , Tempo de Tromboplastina Parcial , Plasmídeos/metabolismo , Domínios Proteicos , Sepse/microbiologia , Análise de Sequência de DNA
5.
Neuroscience ; 260: 23-35, 2014 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-24333801

RESUMO

The dystonias are a group of disorders defined by sustained or intermittent muscle contractions that result in involuntary posturing or repetitive movements. There are many different clinical manifestations and causes. Although they traditionally have been ascribed to dysfunction of the basal ganglia, recent evidence has suggested dysfunction may originate from other regions, particularly the cerebellum. This recent evidence has led to an emerging view that dystonia is a network disorder that involves multiple brain regions. The new network model for the pathogenesis of dystonia has raised many questions, particularly regarding the role of the cerebellum. For example, if dystonia may arise from cerebellar dysfunction, then why are there no cerebellar signs in dystonia? Why are focal cerebellar lesions or degenerative cerebellar disorders more commonly associated with ataxia rather than dystonia? Why is dystonia more commonly associated with basal ganglia lesions rather than cerebellar lesions? Can answers obtained from animals be extrapolated to humans? Is there any evidence that the cerebellum is not involved? Finally, what is the practical value of this new model of pathogenesis for the neuroscientist and clinician? This article explores potential answers to these questions.


Assuntos
Doenças Cerebelares/fisiopatologia , Distonia/fisiopatologia , Rede Nervosa/fisiopatologia , Animais , Doenças dos Gânglios da Base/fisiopatologia , Humanos
7.
Exp Neurol ; 241: 95-104, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23195594

RESUMO

The aim of this study was to search for neuropathological changes in postmortem brain tissue of individuals with cervical dystonia (CD). Multiple regions of formalin-preserved brains were collected from patients with CD and controls and examined with an extensive battery of histopathological stains in a two-stage study design. In stage one, 4 CD brains underwent a broad screening neuropathological examination. In stage two, these 4 CD brains were combined with 2 additional CD brains, and the subjective findings were quantified and compared to 16 age-matched controls. The initial subjective neuropathological assessment revealed only two regions with relatively consistent changes. The substantia nigra had frequent ubiquitin-positive intranuclear inclusions known as Marinesco bodies. Additionally, the cerebellum showed patchy loss of Purkinje cells, areas of focal gliosis and torpedo bodies. Other brain regions showed minor or inconsistent changes. In the second stage of the analysis, quantitative studies failed to reveal significant differences in the numbers of Marinesco bodies in CD versus controls, but confirmed a significantly lower Purkinje cell density in CD. Molecular investigations revealed 4 of the CD cases and 2 controls to harbor sequence variants in non-coding regions of THAP1, and these cases had lower Purkinje cell densities regardless of whether they had CD. The findings suggest that subtle neuropathological changes such as lower Purkinje cell density may be found in primary CD when relevant brain regions are investigated with appropriate methods.


Assuntos
Encéfalo/patologia , Torcicolo/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas Reguladoras de Apoptose/genética , Encéfalo/metabolismo , Proteínas de Ligação a DNA/genética , Feminino , Humanos , Corpos de Inclusão Intranuclear/metabolismo , Corpos de Inclusão Intranuclear/patologia , Corpos de Lewy/patologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/genética , Células de Purkinje/metabolismo , Células de Purkinje/patologia , Torcicolo/genética , Ubiquitina/metabolismo , Adulto Jovem
8.
Mult Scler ; 15(1): 68-74, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18701569

RESUMO

OBJECTIVE: Visual evoked potentials (VEP) may be suitable surrogate outcome measures in multiple sclerosis (MS) remyelination trials. The extent of spontaneous changes of subclinically delayed VEP is unknown, whereas VEP improve after acute optic neuritis (ON). METHODS: In all, 124 patients with three VEP recordings at least 3 months apart: 71 patients with MS who had never suffered clinical ON; 53 patients with ON (isolated ON or ON as an attack of MS at first recording). Latencies of P100 were analyzed by multivariate analysis of variance. RESULTS: Eyes of patients with MS had a mean P100 latency of 110.2 ms, worsening mildly over time (n = 104 eyes, P = 0.022). MS patients' eyes with subclinical demyelination (delayed P100 latency at first recording >116 ms) showed no significant evidence of remyelination (n = 24 eyes, P = 0.27). By contrast, in ON patients' affected eyes, mean P100 latency decreased (P = 0.001), whereas unaffected eyes remained stable (P = 0.26). Clinically non-affected eyes from both diagnostic groups with subclinically prolonged latencies remained stable (n = 32: mean P100 at 124.8 +/- 10.7, 123.5 +/- 13.6, and 122.8 +/- 13.1 ms; P = 0.57), whereas non-affected eyes with normal latency at baseline deteriorated slightly (P = 0.001). A subgroup with more homogeneously defined follow-up periods confirmed this observation. Non-affected eyes selected for stability (difference <5 ms) between first and second recording deteriorated (normal baseline, n = 66 eyes, P = 0.013) or remained stable (prolonged baseline, n = 18 eyes, 95% confidence interval of change -5.42 to +6.89 ms, P = 0.805). CONCLUSION: Prolonged P100 latencies in eyes never affected by clinical ON remain stable and thus can be used as surrogate outcome measure for remyelination trials.


Assuntos
Monitoramento de Medicamentos/métodos , Potenciais Evocados Visuais , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/fisiopatologia , Neurite Óptica/tratamento farmacológico , Neurite Óptica/fisiopatologia , Doença Aguda , Adulto , Ensaios Clínicos como Assunto/métodos , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Análise Multivariada , Tempo de Reação/efeitos dos fármacos , Recuperação de Função Fisiológica/efeitos dos fármacos , Estudos Retrospectivos , Resultado do Tratamento
10.
Brain ; 130(Pt 10): 2484-93, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17575281

RESUMO

Primary episodic ataxias are autosomal dominant channelopathies that manifest as attacks of imbalance and incoordination. Mutations in two genes, KCNA1 and CACNA1A, cause the best characterized and account for the majority of identified cases of episodic ataxia. We summarize current knowledge of clinical and genetic diagnosis, genotype-phenotype correlations, pathophysiology and treatment of episodic ataxia syndromes. We focus on unresolved issues including phenotypic and genetic heterogeneity, lessons from animal models and technological advancement, rationale and feasibility of various treatment strategies, and shared mechanisms underlying episodic ataxia and other far more prevalent paroxysmal conditions such as epilepsy and migraine.


Assuntos
Ataxia Cerebelar/diagnóstico , Animais , Canais de Cálcio/genética , Ataxia Cerebelar/tratamento farmacológico , Ataxia Cerebelar/genética , Diagnóstico Diferencial , Modelos Animais de Doenças , Genótipo , Humanos , Canal de Potássio Kv1.1/genética , Camundongos , Mutação , Fenótipo
11.
Appl Radiat Isot ; 57(2): 185-91, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12150277

RESUMO

2-[18F]Fluoro-L-tyrosine is a fluorine labelled amino acid, known to be incorporated into newly synthesised proteins, rendering it a potentially suitable tracer to image protein metabolism in vivo using positron emission tomography. For the electrophilic preparation of 2-[18F]fluoro-L-tyrosine three protected 2-trialkylstannyl tyrosine derivatives have been synthesised for the first time as precursors. While O,N-di-Boc-2-triethylstannyl-L-tyrosine ethylester has proved to be suitable as precursor for radiosynthesis, imidazolidinon-derivatives of 2-triaklylstannyl tyrosine have not because of difficult fast hydrolysis of a phenolic O-methyl protective group. The di-Boc-tin derivative of tyrosine ethylester readily reacted with [18F]F2, which was prepared via the 18O(p,n)18F nuclear reaction. 2-[18F]Fluoro-L-tyrosine was isolated after full deprotection with aqueous hydrobromic acid and HPLC purification with activities of 1.41 +/- 0.32GBq. The isomeric and enantiomeric purity is high (both >99%). The preparation procedure is facile and easy to automate. The chemical yields of this fluoro-de-stannylation reaction as well as of the synthesis of 6-[18F]fluoro-L-dopa, determined with an analogous precursor and non-radioactive fluorine under identical conditions, amounted to 42.7 +/- 1.6% and 60.2 +/- 2.8%, respectively.

12.
Theor Appl Genet ; 105(4): 629-637, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12582514

RESUMO

Sorghum [ Sorghum bicolor (L.) Moench] is an important crop in the semi-arid tropics that also receives growing attention in genetic research. A comprehensive reference map of the sorghum genome would be an essential research tool. Here, a combined sorghum linkage map from two recombinant inbred populations was constructed using AFLP, SSR, RFLP and RAPD markers. The map was aligned with other published sorghum maps which are briefly reviewed. The two recombinant inbred populations (RIPs) analyzed in this study consisted of 225 (RIP 1) and 226 (RIP 2) F(3:5) lines, developed from the crosses IS 9830 x E 36-1 (RIP 1) and N 13 x E 36-1 (RIP 2), respectively. The genetic map of RIP 1 had a total length of 1,265 cM (Haldane), with 187 markers (125 AFLPs, 45 SSRs, 14 RFLPs, 3 RAPDs) distributed over ten linkage groups. The map of RIP 2 spanned 1,410 cM and contained 228 markers (158 AFLPs, 54 SSRs, 16 RFLPs) in 12 linkage groups. The combined map of the two RIPs contained 339 markers (249 AFLPs, 63 SSRs, 24 RFLPs, 3 RAPDs) on 11 linkage groups and had a length of 1,424 cM. It was in good agreement with other sorghum linkage maps, from which it deviated by a few apparent inversions, deletions, and additional distal regions.

13.
Brain Res Mol Brain Res ; 96(1-2): 114-21, 2001 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-11731016

RESUMO

The SNAP-25 deficient mouse mutant coloboma (Cm/+) is an animal model for investigating the biochemical basis of locomotor hyperactivity. The spontaneous hyperactivity exhibited by coloboma is three times greater than control mice and is a direct result of the SNAP-25 deletion. SNAP-25 is a presynaptic protein that regulates exocytotic neurotransmitter release; coloboma mice express only 50% of normal protein concentrations. Previous research has determined that there is an increase in the concentration of norepinephrine but a decrease in dopamine utilization in the striatum and nucleus accumbens of coloboma mice. In situ hybridization analysis revealed that there were corresponding increases in tyrosine hydroxylase (TH) mRNA expression in noradrenergic cell bodies of the locus coeruleus of Cm/+ mice. In contrast, TH mRNA expression in substantia nigra appeared normal in the mutant mouse. alpha(2)-Adrenergic receptors are important modulators of central noradrenergic function and dopamine release. In situ hybridization data revealed that alpha(2A)-adrenergic receptor mRNA expression is upregulated in Cm/+ mice. These results suggest an underlying abnormality in noradrenergic regulation in this hyperactive mouse mutant.


Assuntos
Catecolaminas/fisiologia , Coloboma/genética , Hipercinese/genética , Glicoproteínas de Membrana , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Tirosina 3-Mono-Oxigenase/genética , Animais , Benzazepinas/metabolismo , Benzazepinas/farmacologia , Corpo Estriado/fisiologia , Antagonistas de Dopamina/metabolismo , Antagonistas de Dopamina/farmacologia , Proteínas da Membrana Plasmática de Transporte de Dopamina , Feminino , Deleção de Genes , Hibridização In Situ , Masculino , Proteínas de Membrana Transportadoras/genética , Camundongos , Camundongos Endogâmicos C3H , Camundongos Mutantes , RNA Mensageiro/análise , Ensaio Radioligante , Receptores Adrenérgicos alfa 2/genética , Receptores Dopaminérgicos/genética , Espiperona/metabolismo , Espiperona/farmacologia , Substância Negra/fisiologia , Proteína 25 Associada a Sinaptossoma , Trítio
14.
J Rheumatol ; 28(9): 1992-8, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11550965

RESUMO

OBJECTIVE: Procainamide related autoimmunity is characterized by the production of antibodies to histones and, in particular, to the H2A-2B dimer. We evaluated in vitro production of antibodies to total histones and the H2A-2B dimer by peripheral blood mononuclear cells (PBMC) from patients chronically exposed to procainamide and related this to in vivo production, and assessed possible immunostimulatory response by the postulated reactive metabolite procainamide hydroxylamine (PAHA) using PAHA conjugated autologous erythrocytes. METHODS: We evaluated in vitro spontaneous and mitogen induced production of histone antibodies by PBMC from 26 asymptomatic patients, who were chronically receiving procainamide, in the presence and absence of PAHA conjugated autologous erythrocytes. Correlations with in vivo production were sought. RESULTS: PBMC from 9 patients revealed significant spontaneous production of histone antibodies, of whom 2 developed procainamide related lupus within 2 mo of the evaluation. There was a significant increase in in vitro production of antibodies to total histones by PBMC that had been cultured in the presence of PAHA-autologous erythrocyte conjugates, but in the absence of mitogens, from 15 (65%) of 23 patients, and of antibodies to H2A-2B by cells from 10 (42%) of 24 patients. Patients' cells that were co-cultured with PAHA-erythrocyte conjugates produced significantly greater amounts of antibodies to both total histones (p = 0.03) and the H2A-2B dimer (p = 0.009) compared with those cultured alone. Co-culture with similarly pretreated erythrocytes also resulted in a significant increase in the production of antibodies to total histones (p < 0.001), but not to the H2A-H2B dimer, by cells from controls. CONCLUSION: Some patients receiving chronic procainamide therapy have spontaneous production of histone antibodies. Co-culture with PAHA-erythrocyte conjugates resulted in significantly greater production, suggesting an immunomodulating effect by this metabolite.


Assuntos
Anticorpos Antinucleares/análise , Histonas/farmacologia , Lúpus Eritematoso Sistêmico/sangue , Procainamida/efeitos adversos , Adulto , Idoso , Anticorpos Antinucleares/biossíntese , Arritmias Cardíacas/tratamento farmacológico , Autoanticorpos/análise , Autoanticorpos/biossíntese , Autoimunidade/efeitos dos fármacos , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Feminino , Histonas/imunologia , Humanos , Assistência de Longa Duração , Estudos Longitudinais , Lúpus Eritematoso Sistêmico/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Monócitos , Probabilidade , Procainamida/administração & dosagem , Valores de Referência , Sensibilidade e Especificidade
15.
Pharmacol Biochem Behav ; 69(3-4): 409-18, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11509198

RESUMO

Iron deficiency (ID) in early life is known to alter neurological development and functioning, but data regarding specific effects on dopamine biology are lacking. The objective of this study was to determine the extent of functional alterations in dopamine receptors in two dopaminergic tracts in young, growing, iron-deficient rats. Forty male and 40 female weanling Sprague-Dawley rats were fed either an iron-deficient (ID) diet or control (CN) diet for 6 weeks. ID decreased densities of D(1) and D(2) receptors in the caudate-putamen and decreased D(2) receptor densities in the nucleus accumbens. There were no apparent effects of ID on the affinities for the ligands in either receptor in several brain regions. In situ hybridization studies for both dopamine receptors revealed no significant effect of ID on mRNA expression for either receptor. Iron-deficient rats had a significantly higher ED(50) for raclopride-induced hypolocomotion in male and female rats compared to control rats of each sex. The loss of iron in the striatum due to dietary ID was significantly correlated with the decrease in D(2) receptor density; however, this relationship was not apparent in other brain regions. These experiments thus demonstrate abnormal dopamine receptor density and functioning in several brain regions that are related to brain regional iron loss. Importantly, the impact of ID on dopamine was more pronounced in males than females, demonstrating sex-related different sensitivities to nutrient deprivation.


Assuntos
Encéfalo/metabolismo , Deficiências de Ferro , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Animais , Encéfalo/efeitos dos fármacos , DNA Complementar/metabolismo , Antagonistas de Dopamina/farmacologia , Feminino , Ferro da Dieta/farmacologia , Masculino , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , RNA Mensageiro/metabolismo , Racloprida/farmacologia , Ratos , Ratos Sprague-Dawley , Fatores Sexuais
16.
Pharmacol Biochem Behav ; 68(4): 669-76, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11526963

RESUMO

The consequences of a reduction in the presynaptic protein, SNAP-25, were investigated to determine the neurochemical basis of the marked hyperlocomotor activity in coloboma (Cm/+) mice. SNAP-25 is part of the minimal presynaptic machinery necessary for exocytotic neurotransmitter release. Reserpine treatment was used to deplete vesicular stores of catecholamines. Coloboma mice were more sensitive to the effects of reserpine than control mice. However, presynaptic regulation of dopamine (DA) release, as assessed by low-dose apomorphine challenge, was intact. There were region-specific reductions in in vivo tyrosine hydroxylation and the DA metabolites homovanillic acid (HVA) and 3,4-dihydroxyphenylacetic acid (DOPAC) in the striatum and nucleus accumbens of Cm/+ mice. While hyperactivity is often associated with changes in DA concentration, norepinephrine (NE) concentration was significantly increased in the striatum and nucleus accumbens of the hyperactive mutant. The increase in NE may regulate the hyperactivity in these mice, as suggested by current hypotheses of the mechanisms underlying attention-deficit hyperactivity disorder (ADHD) and Tourette's syndrome.


Assuntos
Catecolaminas/metabolismo , Hipercinese/metabolismo , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Atividade Motora/fisiologia , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Terminações Pré-Sinápticas/metabolismo , Animais , Apomorfina/farmacologia , Encéfalo/metabolismo , Agonistas de Dopamina/farmacologia , Relação Dose-Resposta a Droga , Hipercinese/genética , Camundongos , Camundongos Endogâmicos C3H , Camundongos Mutantes , Atividade Motora/efeitos dos fármacos , Terminações Pré-Sinápticas/efeitos dos fármacos , Proteína 25 Associada a Sinaptossoma , Tirosina/metabolismo
17.
J Rheumatol ; 28(7): 1735-6, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11469489
18.
J Neurosci Methods ; 105(1): 95-103, 2001 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-11166370

RESUMO

Amperometry is a very powerful technique for investigating the role(s) specific proteins play in exocytosis at the single-cell level. In this study, amperometry has been used to investigate possible changes in exocytosis at chromaffin cells isolated from coloboma and tottering mutant mice. Coloboma mice possess a deletion mutation that encompasses the gene for the presynaptic protein SNAP-25 and tottering mice carry a mutation of the alpha(1A) subunit gene, which encodes the pore-forming region of P/Q-type calcium channels. Although amperometric data measured from tottering and coloboma cells are not significantly different from that measured at wild-type control cells, significant differences are found when groups of wild-type chromaffin cells are analyzed at room temperature and at 37 degrees C. Due to the large variability inherent to amperometric data, it is possible that changes in release resulting from some genetic differences cannot be detected. To fully exploit the technical advantages of using mouse chromaffin cells, experimental guidelines are described which should maximize changes in release resulting from genetic differences and increase the likelihood of detecting a change in amperometric data.


Assuntos
Células Cromafins/metabolismo , Eletrofisiologia/métodos , Exocitose/genética , Proteínas de Membrana/metabolismo , Camundongos Mutantes/anormalidades , Neurotransmissores/metabolismo , Animais , Canais de Cálcio Tipo P/deficiência , Canais de Cálcio Tipo P/genética , Canais de Cálcio Tipo Q/deficiência , Canais de Cálcio Tipo Q/genética , Células Cultivadas/metabolismo , Camundongos , Camundongos Mutantes/genética , Camundongos Mutantes/metabolismo , Microeletrodos , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Proteína 25 Associada a Sinaptossoma
19.
Org Lett ; 3(4): 515-8, 2001 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-11178813

RESUMO

[reaction: see Text] Activation by either high pressure or a combination of Lewis acid catalysis and high pressure allows indole derivatives to behave as dienophiles in [4 + 2] cycloaddition reactions under mild conditions. The biactivation mode has the highest impact on the stereoselectivity of the reaction. The cycloadducts resulting from these reactions are characterized by boat-shape conformations that bear well-defined orthogonal planes.

20.
Mov Disord ; 15(3): 542-51, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10830422

RESUMO

Systemic administration of the L-type calcium channel agonists +/-Bay K 8644 or FPL 64176 causes a characteristic pattern of motor dysfunction in normal C57BL/6J mice that resembles generalized dystonia. There is no associated change in the electroencephalogram, confirming that the motor disorder does not reflect epileptic seizures. However, the electromyogram reveals an increase in baseline motor unit activity with prolonged phasic discharges consistent with dystonia. The duration and severity of dystonia is dependent on the dose administered and the age of the animal at testing. The effects are transient, with the return of normal motor behavior 1-4 hours after treatment. Similar effects can be provoked by intracerebral administration of small amounts of the drugs, indicating a centrally mediated response. Dystonia can be attenuated by co-administration of dihydropyridine L-type calcium channel antagonists (nifedipine, nimodipine, and nitrendipine) but not by non-dihydropyridine antagonists (diltiazem, verapamil, and flunarizine). These results implicate abnormal function of L-type calcium channels in the expression of dystonia in this model.


Assuntos
Éster Metílico do Ácido 3-Piridinacarboxílico, 1,4-Di-Hidro-2,6-Dimetil-5-Nitro-4-(2-(Trifluormetil)fenil)/farmacologia , Agonistas dos Canais de Cálcio/farmacologia , Canais de Cálcio/fisiologia , Distonia/fisiopatologia , Pirróis/farmacologia , Animais , Mapeamento Encefálico , Relação Dose-Resposta a Droga , Eletroencefalografia/efeitos dos fármacos , Eletromiografia/efeitos dos fármacos , Locomoção/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Exame Neurológico/efeitos dos fármacos
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