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1.
Mol Ecol ; 32(16): 4627-4647, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37337956

RESUMO

Phylogeographic patterns in large mammals result from natural environmental factors and anthropogenic effects, which in some cases include domestication. The grey wolf was once widely distributed across the Holarctic, but experienced phylogeographic shifts and demographic declines during the Holocene. In the 19th-20th centuries, the species became extirpated from large parts of Europe due to direct extermination and habitat loss. We reconstructed the evolutionary history of the extinct Western European wolves based on the mitogenomic composition of 78 samples from France (Neolithic-20th century) in the context of other populations of wolves and dogs worldwide. We found a close genetic similarity of French wolves from ancient, medieval and recent populations, which suggests the long-term continuity of maternal lineages. MtDNA haplotypes of the French wolves showed large diversity and fell into two main haplogroups of modern Holarctic wolves. Our worldwide phylogeographic analysis indicated that haplogroup W1, which includes wolves from Eurasia and North America, originated in Northern Siberia. Haplogroup W2, which includes only European wolves, originated in Europe ~35 kya and its frequency was reduced during the Holocene due to an expansion of haplogroup W1 from the east. Moreover, we found that dog haplogroup D, currently restricted to Europe and the Middle East, was nested within the wolf haplogroup W2. This suggests European origin of haplogroup D, probably as a result of an ancient introgression from European wolves. Our results highlight the dynamic evolutionary history of European wolves during the Holocene, with a partial lineage replacement and introgressive hybridization with local dog populations.


Assuntos
Lobos , Cães , Animais , Lobos/genética , Filogenia , Evolução Biológica , Filogeografia , França , Haplótipos/genética , DNA Mitocondrial/genética
2.
J Med Chem ; 63(13): 6774-6783, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32453569

RESUMO

We herein report the first thorough analysis of the structure-permeability relationship of semipeptidic macrocycles. In total, 47 macrocycles were synthesized using a hybrid solid-phase/solution strategy, and then their passive and cellular permeability was assessed using the parallel artificial membrane permeability assay (PAMPA) and Caco-2 assay, respectively. The results indicate that semipeptidic macrocycles generally possess high passive permeability based on the PAMPA, yet their cellular permeability is governed by efflux, as reported in the Caco-2 assay. Structural variations led to tractable structure-permeability and structure-efflux relationships, wherein the linker length, stereoinversion, N-methylation, and peptoids site-specifically impact the permeability and efflux. Extensive nuclear magnetic resonance, molecular dynamics, and ensemble-based three-dimensional polar surface area (3D-PSA) studies showed that ensemble-based 3D-PSA is a good predictor of passive permeability.


Assuntos
Compostos Macrocíclicos/química , Compostos Macrocíclicos/metabolismo , Peptídeos/química , Células CACO-2 , Humanos , Membranas Artificiais , Permeabilidade
3.
Trials ; 17(1): 250, 2016 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-27188795

RESUMO

BACKGROUND: Approximately 15 million persons in the European Union and 10 million persons in the USA are alcohol-dependent. The global burden of disease and injury attributable to alcohol is considerable: worldwide, approximately one in 25 deaths in 2004 was caused by alcohol. At the same time, alcohol use disorders remain seriously undertreated. In this context, alternative or adjunctive therapies such as brain stimulation may play a prominent role. The early results of studies using transcranial direct current stimulation found that stimulations delivered to the dorsolateral prefrontal cortex result in a significant reduction of craving and an improvement of the decision-making processes in various additive disorders. We, therefore, hypothesize that transcranial direct current stimulation can lead to a decrease in alcohol consumption in patients suffering from alcohol use disorders. METHODS/DESIGN: We report the protocol of a randomized, double-blind, placebo-controlled, parallel-group trial, to evaluate the efficacy of transcranial direct current stimulation on alcohol reduction in patients with an alcohol use disorder. The study will be conducted in 14 centers in France and Monaco. Altogether, 340 subjects over 18 years of age and diagnosed with an alcohol use disorder will be randomized to receive five consecutive twice-daily sessions of either active or placebo transcranial direct current stimulation. One session consists in delivering a current flow continuously (anode F4; cathode F3) twice for 13 minutes, with treatments separated by a rest interval of 20 min. Efficacy will be evaluated using the change from baseline (alcohol consumption during the 4 weeks before randomization) to 24 weeks in the total alcohol consumption and number of heavy drinking days. Secondary outcome measures will include alcohol craving, clinical and biological improvements, and the effects on mood and quality of life, as well as cognitive and safety assessments, and, for smokers, an assessment of the effects of transcranial direct current stimulation on tobacco consumption. DISCUSSION: Several studies have reported a beneficial effect of transcranial direct current stimulation on substance use disorders by reducing craving, impulsivity, and risk-taking behavior, and suggest that transcranial direct current stimulation may be a promising treatment in addiction. However, to date, no studies have included sufficiently large samples and sufficient follow-up to confirm the hypothesis. Results from this large randomized controlled trial will give a better overview of the therapeutic potential of transcranial direct current stimulation in alcohol use disorders. TRIAL REGISTRATION: Clinical Trials Gov, NCT02505126 (registration date: July 15 2015).


Assuntos
Abstinência de Álcool , Consumo de Bebidas Alcoólicas/prevenção & controle , Transtornos Relacionados ao Uso de Álcool/terapia , Estimulação Transcraniana por Corrente Contínua , Afeto , Consumo de Bebidas Alcoólicas/fisiopatologia , Consumo de Bebidas Alcoólicas/psicologia , Transtornos Relacionados ao Uso de Álcool/diagnóstico , Transtornos Relacionados ao Uso de Álcool/fisiopatologia , Transtornos Relacionados ao Uso de Álcool/psicologia , Protocolos Clínicos , Cognição , Fissura , Método Duplo-Cego , Feminino , França , Humanos , Masculino , Mônaco , Escalas de Graduação Psiquiátrica , Qualidade de Vida , Projetos de Pesquisa , Fumar/psicologia , Inquéritos e Questionários , Fatores de Tempo , Estimulação Transcraniana por Corrente Contínua/efeitos adversos , Resultado do Tratamento
4.
Brain Stimul ; 8(6): 1168-74, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26590478

RESUMO

BACKGROUND: Further evidence suggests that repetitive Transcranial Magnetic Stimulation (rTMS) is an effective method to reduce tobacco craving among smokers. HYPOTHESIS: As relapse is common within a few days after smoking cessation, we hypothesized that combining the anti-craving effects of rTMS with Nicotine replacement therapy (NRT) to attenuate withdrawal symptoms could increase abstinence rates in smokers with severe nicotine dependence who quit smoking. METHODS: Thirty-seven smokers who failed to quit with the usual treatments were randomly assigned to two treatment groups to receive either active (n = 18) or sham (n = 19) 1-Hz rTMS of the right dorsolateral prefrontal cortex. The day after quitting smoking, each patient combined NRT (21-mg patch) with active or sham rTMS (10 sessions) for 2 weeks. Cessation support was then continued with NRT alone using lower-dose patches. Abstinence rates and self-report craving scales were used to assess the therapeutic results during the combined treatment and for up to 12 weeks after quitting. RESULTS: At the end of the combined treatment, there were significantly more abstinent participants in the active rTMS group (n = 16) than in the sham rTMS group (n = 9) (P = 0.027). The craving scales analysis revealed that active rTMS (P = 0.011) but not sham rTMS (P = 0.116) led to a significant decrease in the compulsive factor. However, no lasting rTMS effect was found. CONCLUSIONS: 1-Hz rTMS combined with NRT improved the success rate of abstinence in smokers during tobacco cessation. The stimulation-induced reduction in compulsivity may explain this result.


Assuntos
Fissura/fisiologia , Córtex Pré-Frontal/fisiologia , Abandono do Hábito de Fumar/métodos , Dispositivos para o Abandono do Uso de Tabaco , Tabagismo/tratamento farmacológico , Tabagismo/terapia , Estimulação Magnética Transcraniana , Adulto , Terapia Combinada/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Método Simples-Cego , Resultado do Tratamento , Adulto Jovem
5.
J Org Chem ; 79(21): 10311-22, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25310174

RESUMO

3-Substituted, 6-substituted, and unsymmetrical 3,6-disubstituted 4-alkylaminopyridazines were prepared from a sequence of three chemo- and regioselective reactions combining amination and palladium-catalyzed cross-coupling reactions, such as reductive dehalogenation and Suzuki-Miyaura reactions. Extension of the methodology to Sonogashira reaction yielded a novel class of 3-substituted pyrrolopyridazines.


Assuntos
Aminas/química , Nitrogênio/química , Piridazinas/química , Pirróis/química , Catálise , Estrutura Molecular , Paládio/química
6.
J Org Chem ; 78(16): 7930-7, 2013 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-23844999

RESUMO

N-Heteroaryl-α-amino acid derivatives are valuable pharmacological agents as peptidomimetics. Classical SNAr methods using acid catalysis and elevated temperatures could not be extended to various α-amino acids and fairly electrophilic heterocyclic partners. Here, we report a mild and versatile method of N-heteroarylation of chiral α-aminoesters without racemization, involving Buchwald-Hartwig conditions. It could be extended to various α-amino acids and azines. This efficient N-heteroarylation leads to (i) a chemical library of putative peptidomimetics combining diverse azaheterocycles with the chiral α-aminoesters and their corresponding derivatives (amides, alcohols, etc.) and (ii) arginine derivatives designed as NPFF receptor ligands.


Assuntos
Aminoácidos/síntese química , Ésteres/síntese química , Paládio/química , Aminoácidos/química , Catálise , Ésteres/química , Estrutura Molecular
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