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1.
MicroPubl Biol ; 20232023.
Artigo em Inglês | MEDLINE | ID: mdl-37680216

RESUMO

Mutant B.4.1 , generated via EMS mutagenesis in Drosophila melanogaster , was studied by undergraduate students participating in the Fly-CURE. After inducing genetically mosaic tissue in the adult eye, B.4.1 mutant tissue displays a robust increase in cell division and a rough appearance. Complementation mapping and sequence analysis identified a nonsense mutation in the gene CG1603 , which we named clifford ( cliff ) due to observed increases in red-pigmented mutant tissue compared to controls. cliff encodes a zinc finger-containing protein implicated in transcriptional control. RNAi knockdown of cliff similarly results in rough eyes, confirming a role for Cliff in eye development.

2.
Transl Psychiatry ; 11(1): 29, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33431833

RESUMO

Substance use disorders (SUDs) are characterized by a compulsion to seek and consume one or more substances of abuse, with a perceived loss of control and a negative emotional state. Prolonged substance use seems to be associated with morphological changes of multiple neural circuits, in particular the frontal-striatal and limbic pathways. Such neuroadaptations are evident across several substance disorders, but may vary depending on the type of substance, consumption severity and/or other unknown factors. We therefore identified studies investigating the effects of SUDs using volumetric whole-brain voxel-based morphometry (VBM) in gray (GM) and white matter (WM). We performed a systematic review and meta-analysis of VBM studies using the anatomic likelihood estimation (ALE) method implemented in GingerALE (PROSPERO pre-registration CRD42017071222 ). Sixty studies met inclusion criteria and were included in the final quantitative meta-analysis, with a total of 614 foci, 94 experiments and 4938 participants. We found convergence and divergence in brain regions and volume effects (higher vs. lower volume) in GM and WM depending on the severity of the consumption pattern and type of substance used. Convergent pathology was evident across substances in GM of the insula, anterior cingulate cortex, putamen, and thalamus, and in WM of the thalamic radiation and internal capsule bundle. Divergent pathology between occasional use (cortical pathology) and addiction (cortical-subcortical pathology) provides evidence of a possible top-down neuroadaptation. Our findings indicate particular brain morphometry alterations in SUDs, which may inform our understanding of disease progression and ultimately therapeutic approaches.


Assuntos
Transtornos Relacionados ao Uso de Substâncias , Substância Branca , Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Neuroimagem , Transtornos Relacionados ao Uso de Substâncias/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
3.
Artigo em Inglês | MEDLINE | ID: mdl-33508499

RESUMO

BACKGROUND: Cocaine use disorder (CUD) is a global condition lacking effective treatment. Repetitive transcranial magnetic stimulation (rTMS) may reduce craving and frequency of cocaine use, but little is known about its efficacy and neural effects. We sought to elucidate short- and long-term clinical benefits of 5-Hz rTMS as an add-on to standard treatment in patients with CUD and discern underlying functional connectivity effects using magnetic resonance imaging. METHODS: A total of 44 patients with CUD were randomly assigned to complete the 2-week double-blind randomized controlled trial (acute phase) (sham [n = 20, 2 female] and active [n = 24, 4 female]), in which they received two daily sessions of rTMS on the left dorsolateral prefrontal cortex (PFC). Subsequently, 20 patients with CUD continued to an open-label maintenance phase for 6 months (two weekly sessions for up to 6 mo). RESULTS: rTMS plus standard treatment for 2 weeks significantly reduced craving (baseline: 3.9 ± 3.6; 2 weeks: 1.5 ± 2.4, p = .013, d = 0.77) and impulsivity (baseline: 64.8 ± 16.8; 2 weeks: 53.1 ± 17.4, p = .011, d = 0.79) in the active group. We also found increased functional connectivity between the left dorsolateral PFC and ventromedial PFC and between the ventromedial PFC and right angular gyrus. Clinical and functional connectivity effects were maintained for 3 months, but they dissipated by 6 months. We did not observe reduction in positive results for cocaine in urine; however, self-reported frequency and grams consumed for 6 months were reduced. CONCLUSIONS: With this randomized controlled trial, we show that 5-Hz rTMS has potential promise as an adjunctive treatment for CUD and merits further research.


Assuntos
Cocaína , Estimulação Magnética Transcraniana , Fissura , Método Duplo-Cego , Feminino , Humanos , Masculino , Córtex Pré-Frontal
4.
Acta Biochim Pol ; 54(2): 387-99, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17565386

RESUMO

N-Acetylmannosamine (ManNAc) is the first committed intermediate in sialic acid metabolism. Thus, the mechanisms that control intracellular ManNAc levels are important regulators of sialic acid production. In prokaryotic organisms, UDP-N-acetylglucosamine (GlcNAc) 2-epimerase and GlcNAc-6-P 2-epimerase are two enzymes capable of generating ManNAc from UDP-GlcNAc and GlcNAc-6-P, respectively. We have purified for the first time native GlcNAc-6-P 2-epimerase from bacterial source to apparent homogeneity (1 200 fold) using Butyl-agarose, DEAE-FPLC and Mannose-6-P-agarose chromatography. By SDS/PAGE the pure enzyme showed a molecular mass of 38.4 +/- 0.2 kDa. The maximum activity was achieved at pH 7.8 and 37 degrees C. Under these conditions, the K(m) calculated for GlcNAc-6-P was 1.5 mM. The 2-epimerase activity was activated by Na(+) and inhibited by mannose-6-P but not mannose-1-P. Genetic analysis revealed high homology with bacterial isomerases. GlcNAc-6-P 2-epimerase from E. coli K92 is a ManNAc-inducible protein and is detected from the early logarithmic phase of growth. Our results indicate that, unlike UDP-GlcNAc 2-epimerase, which promotes the biosynthesis of sialic acid, GlcNAc-6-P 2-epimerase plays a catabolic role. When E. coli grows using ManNAc as a carbon source, this enzyme converts the intracellular ManNAc-6-P generated into GlcNAc-6-P, diverting the metabolic flux of ManNAc to GlcNAc.


Assuntos
Carboidratos Epimerases/isolamento & purificação , Carboidratos Epimerases/metabolismo , Escherichia coli/enzimologia , Sequência de Aminoácidos , Bactérias/enzimologia , Bactérias/genética , Sequência de Bases , Carboidratos Epimerases/química , Carboidratos Epimerases/genética , Cátions/farmacologia , DNA Bacteriano/genética , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Hexosaminas/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Dados de Sequência Molecular , Peso Molecular , Ácido N-Acetilneuramínico/metabolismo , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/isolamento & purificação , Homologia de Sequência de Aminoácidos , Especificidade por Substrato
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