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1.
Nature ; 576(7787): 416-422, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31853084

RESUMO

Magnetic topological insulators are narrow-gap semiconductor materials that combine non-trivial band topology and magnetic order1. Unlike their nonmagnetic counterparts, magnetic topological insulators may have some of the surfaces gapped, which enables a number of exotic phenomena that have potential applications in spintronics1, such as the quantum anomalous Hall effect2 and chiral Majorana fermions3. So far, magnetic topological insulators have only been created by means of doping nonmagnetic topological insulators with 3d transition-metal elements; however, such an approach leads to strongly inhomogeneous magnetic4 and electronic5 properties of these materials, restricting the observation of important effects to very low temperatures2,3. An intrinsic magnetic topological insulator-a stoichiometric well ordered magnetic compound-could be an ideal solution to these problems, but no such material has been observed so far. Here we predict by ab initio calculations and further confirm using various experimental techniques the realization of an antiferromagnetic topological insulator in the layered van der Waals compound MnBi2Te4. The antiferromagnetic ordering  that MnBi2Te4  shows makes it invariant with respect to the combination of the time-reversal and primitive-lattice translation symmetries, giving rise to a ℤ2 topological classification; ℤ2 = 1 for MnBi2Te4, confirming its topologically nontrivial nature. Our experiments indicate that the symmetry-breaking (0001) surface of MnBi2Te4 exhibits a large bandgap in the topological surface state. We expect this property to eventually enable the observation of a number of fundamental phenomena, among them quantized magnetoelectric coupling6-8 and axion electrodynamics9,10. Other exotic phenomena could become accessible at much higher temperatures than those reached so far, such as the quantum anomalous Hall effect2 and chiral Majorana fermions3.

2.
Phys Rev Lett ; 129(11): 112501, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36154392

RESUMO

The reduced transition probabilities for the 4_{1}^{+}→2_{1}^{+} and 2_{1}^{+}→0_{1}^{+} transitions in ^{92}Mo and ^{94}Ru and for the 4_{1}^{+}→2_{1}^{+} and 6_{1}^{+}→4_{1}^{+} transitions in ^{90}Zr have been determined in this experiment making use of a multinucleon transfer reaction. These results have been interpreted on the basis of realistic shell-model calculations in the f_{5/2}, p_{3/2}, p_{1/2}, and g_{9/2} proton valence space. Only the combination of extensive lifetime information and large scale shell-model calculations allowed the extent of the seniority conservation in the N=50 g_{9/2} orbital to be understood. The conclusion is that seniority is largely conserved in the first πg_{9/2} orbital.

3.
Phys Rev Lett ; 126(17): 176403, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33988442

RESUMO

Using angle-resolved photoelectron spectroscopy (ARPES), we investigate the surface electronic structure of the magnetic van der Waals compounds MnBi_{4}Te_{7} and MnBi_{6}Te_{10}, the n=1 and 2 members of a modular (Bi_{2}Te_{3})_{n}(MnBi_{2}Te_{4}) series, which have attracted recent interest as intrinsic magnetic topological insulators. Combining circular dichroic, spin-resolved and photon-energy-dependent ARPES measurements with calculations based on density functional theory, we unveil complex momentum-dependent orbital and spin textures in the surface electronic structure and disentangle topological from trivial surface bands. We find that the Dirac-cone dispersion of the topologial surface state is strongly perturbed by hybridization with valence-band states for Bi_{2}Te_{3}-terminated surfaces but remains preserved for MnBi_{2}Te_{4}-terminated surfaces. Our results firmly establish the topologically nontrivial nature of these magnetic van der Waals materials and indicate that the possibility of realizing a quantized anomalous Hall conductivity depends on surface termination.

4.
Allergol Immunopathol (Madr) ; 48(6): 568-575, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32402626

RESUMO

INTRODUCTION AND OBJECTIVES: The diagnosis of IgE-mediated cow's milk allergy (CMA) is often based on clinical history and on specific IgE levels and/or skin-prick tests (SPT), both of which are sensitive but not specific. The gold standard, oral food challenge (OFC), is expensive and time-consuming and involves a risk of severe allergic reactions. This study aimed to determine the value of specific IgEs, ratios of specific IgEs for cow's milk and its components to total IgE, and wheal size on SPT for predicting a positive OFC for CMA. MATERIAL AND METHODS: We retrospectively studied 72 patients [median age, four years; age range 0.75-15 years] sensitized to cow's milk who underwent OFCs to milk. predictive variables between patients with positive and negative OFCs were compared. Receiver operator characteristic (ROC) curves were uses to assess variables' discriminatory capacity and Youden's index to determine the best cut-offs for predicting CMA. RESULTS: The OFC was positive in 39 (54%) patients. Wheal size on SPT and all specific IgEs and specific-to-total IgE ratios were significantly different between patients with positive OFCs and those with negative OFCs (p<0.001). The variable with the greatest area under the ROC curve was casein-specific IgE (0.98), followed by ß-lactoglobulin-specific IgE (0.923), casein-specific-to-total-IgE ratio (0.919), and α-lactalbumin-specific IgE (0.908). Casein-specific IgE ≥0.95kU/L yielded 88.9% sensitivity and 90.9% specificity. CONCLUSIONS: In our center, casein-specific IgE >0.95kU/L can obviate an OFC to cow's milk for the diagnosis of CMA in patients sensitized to cow's milk with a compatible history.


Assuntos
Alérgenos/administração & dosagem , Imunoglobulina E/sangue , Hipersensibilidade a Leite/diagnóstico , Proteínas do Leite/administração & dosagem , Administração Oral , Adolescente , Alérgenos/imunologia , Animais , Bovinos , Criança , Pré-Escolar , Feminino , Humanos , Imunoglobulina E/imunologia , Lactente , Masculino , Hipersensibilidade a Leite/sangue , Hipersensibilidade a Leite/imunologia , Proteínas do Leite/imunologia , Curva ROC , Valores de Referência , Estudos Retrospectivos
5.
Rev Sci Tech ; 38(3): 737-749, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-32286570

RESUMO

Equine influenza is one of the major respiratory infectious diseases in horses. In 2018, equine influenza virus (EIV) was confirmed as the cause of outbreaks of respiratory disease in horses in Chile and Argentina. In the same year, for the first time in Uruguay, EIV infection was confirmed by isolation and molecular analysis to be the cause of respiratory disease among hundreds of clinically affected thoroughbred horses in training and racing facilities. The virus was detected in nasopharyngeal swabs by a pan-reactive influenza type A realtime reverse transcription polymerase chain reaction (rRT-PCR). The partial nucleotide sequence of the haemagglutinin 1 (HA1 ) gene (994 base pairs) was determined and analysed phylogenetically using MEGA X software. Amino acid sequence alignments were constructed, and serum samples were tested by haemagglutination inhibition and single radial haemolysis. The diagnosis of EIV was confirmed by rRT-PCR, virus isolation and serological testing. The phylogenetic analysis of the partial HA1 gene sequence of the isolated virus indicated that it belongs to clade 1 of the Florida sub-lineage of the American lineage and is closely related to viruses isolated in the recent past. Study of the HA1 region (331 amino acids) of the virus identified in horses in racing facilities in Uruguay displayed the highest amino acid sequence identity with viruses detected in Argentina, Chile and the United Kingdom in 2018. The surveillance data reported illustrate the international spread of EIVs and support the recommendation of the World Organisation for Animal Health (OIE) Expert Surveillance Panel to include viruses of the Florida sub-lineage in vaccines.


La grippe équine est l'une des principales maladies respiratoires infectieuses affectant les équidés. En 2018, il a été confirmé que des foyers de maladie respiratoire enregistrés chez des chevaux au Chili et en Argentine étaient dus au virus de la grippe équine. Cette même année en Uruguay, pour la première fois dans ce pays, il a été établi par isolement viral et par des méthodes moléculaires que le virus de la grippe équine était l'agent causal d'une maladie respiratoire affectant cliniquement des centaines de chevaux pur-sang dans des centres d'entraînement et des hippodromes. La détection du virus s'est faite à partir d'écouvillons prélevés par voie naso-pharyngée en appliquant une technique d'amplification en chaîne par polymérase couplée à une transcription inverse en temps réel (rRT­PCR) à large spectre pour les virus influenza de type A. Une séquence nucléotidique partielle correspondant au gène de l'hémagglutinine 1 (HA1) (994 paires de bases) a fait l'objet d'une analyse phylogénétique au moyen du programme informatique MEGA X. Il a été procédé à la construction d'une matrice d'alignements de ces séquences d'acides aminés. D'autre part, des prélèvements de sérum issus de chevaux atteints ont été soumis à l'épreuve d'inhibition de l'hémagglutination et à une hémolyse radiale unique. Aussi bien la rRT­PCR que l'isolement viral et l'analyse sérologique ont confirmé le diagnostic de l'infection par le virus de la grippe équine. Il ressort de l'analyse phylogénétique du fragment de séquence du gène HA1 du virus isolé que ce dernier appartient au clade 1 de la sous-lignée Florida de la lignée américaine et qu'il est étroitement apparenté à des virus isolés au cours des dernières années. L'étude de la région HA1 (331 acides aminés) du virus détecté chez des chevaux de course en Uruguay a montré que les virus qui présentaient la plus grande similitude avec cette séquence d'acides aminés étaient ceux détectés en Argentine, au Chili et au Royaume-Uni en 2018. Les données de surveillance rapportées illustrent la propagation à l'échelle internationale des virus de la grippe équine et renforcent la recommandation émise par le Groupe d'experts de l'Organisation mondiale de la santé animale (OIE) chargé de la surveillance de la composition des vaccins contre la grippe équine d'inclure les virus de la sous-lignée Florida dans la composition de ces vaccins.


La gripe equina es una de las principales infecciones respiratorias que afectan al caballo. En 2018 se confirmó que el virus de la gripe equina era la causa de diversos brotes de afección respiratoria que habían afectado a caballos de Chile y Argentina. Ese mismo año, por primera vez en el Uruguay, se confirmó por aislamiento y análisis molecular que el virus de la gripe equina era la causa de una infección respiratoria que, acompañada de manifestaciones clínicas, afectó a cientos de caballos purasangre de hipódromos y centros de adiestramiento. El virus fue detectado en muestras de frotis nasales mediante una técnica de reacción en cadena de la polimerasa acoplada a transcripción inversa en tiempo real (rRT­PCR, por sus siglas en inglés) que reacciona ante todos los virus gripales de tipo A. Tras secuenciar parcialmente el gen de la hemaglutinina 1 (HA1 ) (994 pares de bases), se procedió a su análisis filogenético empleando el programa informático MEGA X. Además de crear una matriz de alineamiento de secuencias de aminoácidos, se sometieron muestras de suero a pruebas de inhibición de la hemaglutinación y hemólisis radial simple. Así, el diagnóstico que apuntaba al virus de la gripe equina fue confirmado por rRT­PCR, aislamiento vírico y análisis serológico. El análisis filogenético de la secuencia parcial del gen HA1 del virus aislado puso de manifiesto que pertenece al clado 1 del sublinaje Florida del linaje americano y guarda estrecho parentesco con otros virus aislados en fechas recientes. El estudio de la región HA1 (331 aminoácidos) del virus detectado en caballos de hipódromos uruguayos reveló que el mayor nivel de concordancia de su secuencia de aminoácidos se daba con virus detectados en Argentina, Chile y el Reino Unido en 2018. Los datos de vigilancia comunicados dan fe de la propagación internacional de los virus de la gripe equina y avalan la recomendación formulada por el Panel de expertos en vigilancia de la composición de las vacunas contra la gripe equina de la Organización Mundial de Sanidad Animal (OIE), que aboga por incluir virus del sublinaje Florida en las vacunas.


Assuntos
Doenças dos Cavalos/epidemiologia , Doenças dos Cavalos/virologia , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/virologia , Animais , Surtos de Doenças , Cavalos , Filogenia , Uruguai/epidemiologia
6.
Phys Rev Lett ; 121(19): 192502, 2018 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-30468583

RESUMO

Lifetime measurements of excited states of the light N=52 isotones ^{88}Kr, ^{86}Se, and ^{84}Ge have been performed, using the recoil distance Doppler shift method and VAMOS and AGATA spectrometers for particle identification and gamma spectroscopy, respectively. The reduced electric quadrupole transition probabilities B(E2;2^{+}→0^{+}) and B(E2;4^{+}→2^{+}) were obtained for the first time for the hard-to-reach ^{84}Ge. While the B(E2;2^{+}→0^{+}) values of ^{88}Kr, ^{86}Se saturate the maximum quadrupole collectivity offered by the natural valence (3s, 2d, 1g_{7/2}, 1h_{11/2}) space of an inert ^{78}Ni core, the value obtained for ^{84}Ge largely exceeds it, suggesting that shape coexistence phenomena, previously reported at N≲49, extend beyond N=50. The onset of collectivity at Z=32 is understood as due to a pseudo-SU(3) organization of the proton single-particle sequence reflecting a clear manifestation of pseudospin symmetry. It is realized that the latter provides actually reliable guidance for understanding the observed proton and neutron single particle structure in the whole medium-mass region, from Ni to Sn, pointing towards the important role of the isovector-vector ρ field in shell-structure evolution.

7.
Phys Rev Lett ; 118(16): 162501, 2017 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-28474951

RESUMO

Prompt γ-ray spectroscopy of the neutron-rich ^{96}Kr, produced in transfer- and fusion-induced fission reactions, has been performed using the combination of the Advanced Gamma Tracking Array and the VAMOS++ spectrometer. A second excited state, assigned to J^{π}=4^{+}, is observed for the first time, and a previously reported level energy of the first 2^{+} excited state is confirmed. The measured energy ratio R_{4/2}=E(4^{+})/E(2^{+})=2.12(1) indicates that this nucleus does not show a well-developed collectivity contrary to that seen in heavier N=60 isotones. This new measurement highlights an abrupt transition of the degree of collectivity as a function of the proton number at Z=36, of similar amplitude to that observed at N=60 at higher Z values. A possible reason for this abrupt transition could be related to the insufficient proton excitations in the g_{9/2}, d_{5/2}, and s_{1/2} orbitals to generate strong quadrupole correlations or to the coexistence of competing different shapes. An unexpected continuous decrease of R_{4/2} as a function of the neutron number up to N=60 is also evidenced. This measurement establishes the Kr isotopic chain as the low-Z boundary of the island of deformation for N=60 isotones. A comparison with available theoretical predictions using different beyond mean-field approaches shows that these models fail to reproduce the abrupt transitions at N=60 and Z=36.

8.
Mol Psychiatry ; 21(3): 328-38, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26100539

RESUMO

Major depression brings about a heavy socio-economic burden worldwide due to its high prevalence and the low efficacy of antidepressant drugs, mostly inhibiting the serotonin transporter (SERT). As a result, ~80% of patients show recurrent or chronic depression, resulting in a poor quality of life and increased suicide risk. RNA interference (RNAi) strategies have been preliminarily used to evoke antidepressant-like responses in experimental animals. However, the main limitation for the medical use of RNAi is the extreme difficulty to deliver oligonucleotides to selected neurons/systems in the mammalian brain. Here we show that the intranasal administration of a sertraline-conjugated small interfering RNA (C-SERT-siRNA) silenced SERT expression/function and evoked fast antidepressant-like responses in mice. After crossing the permeable olfactory epithelium, the sertraline-conjugated-siRNA was internalized and transported to serotonin cell bodies by deep Rab-7-associated endomembrane vesicles. Seven-day C-SERT-siRNA evoked similar or more marked responses than 28-day fluoxetine treatment. Hence, C-SERT-siRNA (i) downregulated 5-HT1A-autoreceptors and facilitated forebrain serotonin neurotransmission, (ii) accelerated the proliferation of neuronal precursors and (iii) increased hippocampal complexity and plasticity. Further, short-term C-SERT-siRNA reversed depressive-like behaviors in corticosterone-treated mice. The present results show the feasibility of evoking antidepressant-like responses by selectively targeting neuronal populations with appropriate siRNA strategies, opening a way for further translational studies.


Assuntos
Antidepressivos/administração & dosagem , Depressão/tratamento farmacológico , RNA Interferente Pequeno/administração & dosagem , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Sertralina/administração & dosagem , Administração Intranasal , Animais , Proteínas de Arabidopsis/metabolismo , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Corticosterona/sangue , DNA Antissenso/farmacologia , Depressão/patologia , Modelos Animais de Doenças , Endocitose/efeitos dos fármacos , Comportamento Exploratório/efeitos dos fármacos , Fluoxetina/administração & dosagem , Regulação da Expressão Gênica/efeitos dos fármacos , Transferases Intramoleculares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fosfopiruvato Hidratase/metabolismo , Serotonina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Fatores de Tempo
9.
Phys Rev Lett ; 117(22): 222302, 2016 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-27925748

RESUMO

The ^{54}Fe nucleus was populated from a ^{56}Fe beam impinging on a Be target with an energy of E/A=500 MeV. The internal decay via γ-ray emission of the 10^{+} metastable state was observed. As the structure of this isomeric state has to involve at least four unpaired nucleons, it cannot be populated in a simple two-neutron removal reaction from the ^{56}Fe ground state. The isomeric state was produced in the low-momentum (-energy) tail of the parallel momentum (energy) distribution of ^{54}Fe, suggesting that it was populated via the decay of the Δ^{0} resonance into a proton. This process allows the population of four-nucleon states, such as the observed isomer. Therefore, it is concluded that the observation of this 10^{+} metastable state in ^{54}Fe is a consequence of the quark structure of the nucleons.

10.
Eur J Clin Microbiol Infect Dis ; 35(8): 1269-76, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27180242

RESUMO

Switching from intravenous to oral antibiotic therapy may improve inpatient management and reduce hospital stays and the complications of intravenous treatment. We aimed to assess the effectiveness of intravenous-to-oral antibiotic switch therapy and an early discharge algorithm in hospitalized patients with gram-positive infection. We performed a prospective cohort study with a retrospective comparison cohort, recruited from eight tertiary, acute-care Spanish referral hospitals. All patients included had culture-confirmed methicillin-resistant gram-positive infection, or methicillin-susceptible gram-positive infection and beta-lactam allergy and had received intravenous treatment with glycopeptides, lipopeptides, or linezolid. The study comprised two cohorts: the prospective cohort to assess the effectiveness of a sequential intravenous-to-oral antibiotic switch algorithm and early discharge, and a retrospective cohort in which the algorithm had not been applied, used as the comparator. A total of 247 evaluable patients were included; 115 in the prospective and 132 in the retrospective cohort. Forty-five retrospective patients (34 %) were not changed to oral antibiotics, and 87 (66 %) were changed to oral antibiotics without following the proposed algorithm. The duration of hospitalization was significantly shorter in the prospective cohort compared to the retrospective group that did not switch to oral drugs (16.7 ± 18.7 vs 23 ± 13.4 days, P < 0.001). No differences were observed regarding the incidence of catheter-related bacteraemia (4.4 % vs 2.6 %, P = 0.621). Our results suggest that an intravenous-to-oral antibiotic switch strategy is effective for reducing the length of hospital stay in selected hospitalized patients with gram-positive infection.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Administração Intravenosa , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Feminino , Infecções por Bactérias Gram-Positivas/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Espanha , Resultado do Tratamento
11.
Epidemiol Infect ; 143(6): 1187-93, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25148565

RESUMO

Patagonia in southern South America is among the few world regions where direct human impact is still limited but progressively increasing, mainly represented by tourism, farming, fishing and mining activities. The sanitary condition of Patagonian wildlife is unknown, in spite of being critical for the assessment of anthropogenic effects there. The aim of this study was the characterization of Salmonella enterica strains isolated from wild colonies of Magellanic penguins (Spheniscus magellanicus) located in Magdalena Island and Otway Sound, in Chilean Patagonia. Eight isolates of Salmonella were found, belonging to Agona and Enteritidis serotypes, with an infection rate of 0·38%. Resistance to ampicillin, cefotaxime, ceftiofur and tetracycline antimicrobials were detected, and some of these strains showed genotypic similarity with Salmonella strains isolated from humans and gulls, suggesting inter-species transmission cycles and strengthening the role of penguins as sanitary sentinels in the Patagonian ecosystem.


Assuntos
Salmonelose Animal/transmissão , Salmonella enterica , Spheniscidae/microbiologia , Animais , Animais Selvagens/microbiologia , Antibacterianos/farmacologia , Charadriiformes/microbiologia , Chile/epidemiologia , Farmacorresistência Bacteriana , Ecossistema , Humanos , Infecções por Salmonella/transmissão , Salmonelose Animal/epidemiologia , Salmonelose Animal/microbiologia , Salmonella enterica/efeitos dos fármacos
12.
Genet Mol Res ; 14(2): 6073-83, 2015 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-26125808

RESUMO

Innate pathway activation is fundamental for early anti-viral defense in fish, but currently there is insufficient understanding of how salmonid fish identify viral molecules and activate these pathways. The Toll-like receptor (TLR) is believed to play a crucial role in host defense of pathogenic microbes in the innate immune system. In the present study, the full-length cDNA of Salmo salar TLR3 (ssTLR3) was cloned. The ssTLR3 cDNA sequence was 6071 bp long, containing an open reading frame of 2754 bp and encoding 971 amino acids. The TLR group motifs, such as leucine-rich repeat (LRR) domains and Toll-interleukin-1 receptor (TIR) domains, were maintained in ssTLR3, with sixteen LRR domains and one TIR domain. In contrast to descriptions of the TLR3 in rainbow trout and the murine (TATA-less), we found a putative TATA box in the proximal promoter region 29 bp upstream of the transcription start point of ssTLR3. Multiple-sequence alignment analysis of the ssTLR3 protein-coding sequence with other known TLR3 sequences showed the sequence to be conserved among all species analyzed, implying that the function of the TLR3 had been sustained throughout evolution. The ssTLR3 mRNA expression patterns were measured using real-time PCR. The results revealed that TLR3 is widely expressed in various healthy tissues. Individuals challenged with infectious pancreatic necrosis virus and immunostimulated with polyinosinic:polycytidylic acid exhibited increased expression of TLR3 at the mRNA level, indicating that ssTLR3 may be involved in pathogen recognition in the early innate immune system.


Assuntos
Clonagem Molecular/métodos , Imunidade Inata , Salmo salar/genética , Salmo salar/imunologia , Receptor 3 Toll-Like/genética , Animais , Resistência à Doença , Evolução Molecular , Vírus da Necrose Pancreática Infecciosa/fisiologia , Filogenia , Poli I-C/farmacologia , Salmo salar/virologia , Análise de Sequência de DNA , Receptor 3 Toll-Like/química
13.
Compr Psychiatry ; 55(3): 639-49, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24411652

RESUMO

OBJECTIVE: The main objective was to explore early-age conditions associated to Substance Use Disorders (SUD) in adults with Attention Deficit/Hyperactivity Disorder (ADHD); secondly, to determine which of those conditions are specific to ADHD subjects; and finally, to compare ADHD and non-ADHD subjects in terms of SUD lifetime prevalence and professional, social and personal adjustment. METHOD: Comparison between ADHD adults with (n=236) and without lifetime SUD (n=309) regarding clinical characteristics of ADHD, externalization disorders, temperamental traits, environmental factors, academic history and family psychiatric history; secondly, ADHD subjects were compared to a non-ADHD group (n=177) concerning those variables. RESULTS: The following variables were found to be positively associated to SUD in ADHD subjects: ADHD severity, CD and ODD comorbidities, temperamental characteristics ("fearful", "accident prone" and "frequent temper tantrums"), "sexual abuse", "be suspended from school", family history of SUD and ADHD, and male gender; ADHD inattentive subtype and "fearful" were inversely associated to SUD. From those variables, "frequent temper tantrums" was also associated to SUD in non-ADHD subjects. ADHD subjects had higher prevalence of lifetime SUD and greater professional, social and personal impairment than non-ADHD subjects. CONCLUSION: Findings suggest a significant association between ADHD, SUD and early-age conditions, such as CD and ODD comorbidity; other variables from childhood, namely, ADHD subtype, temper characteristics ("fearful", "accident prone"), "sexual abuse", "be suspended from school" and family history of ADHD are associated to SUD in ADHD subjects, but not in non-ADHD subjects. Moreover, this study confirms both the higher prevalence of lifetime SUD and greater professional, social and personal impairment in ADHD subjects than in non-ADHD subjects.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Ajustamento Social , Transtornos Relacionados ao Uso de Substâncias/psicologia , Temperamento , Adulto , Atenção , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Estudos de Casos e Controles , Comorbidade , Feminino , Humanos , Masculino , Prevalência , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Adulto Jovem
14.
Fish Physiol Biochem ; 40(3): 887-96, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24306554

RESUMO

Infectious pancreatic necrosis virus (IPNV) is an economically important pathogen of the salmonid aquaculture industry. Selective breeding has been employed to improve resistance to this infectious disease, and it is of importance to investigate the expression profile of immune genes of Atlantic salmon with different genetic background in response to this virus. This study examined the immune modulation response of eight candidate genes in head kidney tissue in two families of Atlantic salmon with high and low mortalities, after challenge with IPNV. The results showed that the expression pattern of target genes differed in the two families. Generally, higher expression of antiviral, pro-inflammatory genes and transcription factors such as tripartite motif, NF-κB, IFNI, STAT1, protein kinase R, and Vig-2 in the resistant family were observed at the same time point. One may speculate the functional importance of these putative candidate genes in the characterization of the IPNV-resistant (low mortalities) immune phenotype. Therefore, on our findings, we suggest that future salmonids studies aiming to identify candidate genes/pathway or vaccines evaluation should consider validating detected genes/pathway across different genetic backgrounds or immune phenotype.


Assuntos
Infecções por Birnaviridae/veterinária , Doenças dos Peixes/virologia , Interações Hospedeiro-Patógeno/imunologia , Vírus da Necrose Pancreática Infecciosa/fisiologia , Salmo salar/virologia , Animais , Infecções por Birnaviridae/imunologia , Doenças dos Peixes/imunologia , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Interações Hospedeiro-Patógeno/genética , Interferon-alfa/metabolismo , NF-kappa B/metabolismo , Fator de Transcrição STAT1/metabolismo , Salmo salar/fisiologia , Fator de Crescimento Transformador beta1/metabolismo
15.
Genet Mol Res ; 11(1): 182-9, 2012 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-22370885

RESUMO

Landfarm soils are employed in industrial and petrochemical residue bioremediation. This process induces selective pressure directed towards microorganisms capable of degrading toxic compounds. Detailed description of taxa in these environments is difficult due to a lack of knowledge of culture conditions required for unknown microorganisms. A metagenomic approach permits identification of organisms without the need for culture. However, a DNA extraction step is first required, which can bias taxonomic representativeness and interfere with cloning steps by extracting interference substances. We developed a simplified DNA extraction procedure coupled with metagenomic DNA amplification in an effort to overcome these limitations. The amplified sequences were used to generate a metagenomic data set and the taxonomic and functional representativeness were evaluated in comparison with a data set built with DNA extracted by conventional methods. The simplified and optimized method of RAPD to access metagenomic information provides better representativeness of the taxonomical and metabolic aspects of the environmental samples.


Assuntos
DNA Bacteriano/análise , Metagenômica/métodos , Técnica de Amplificação ao Acaso de DNA Polimórfico/métodos , Microbiologia do Solo , Agricultura/métodos , DNA Bacteriano/genética , Metagenoma/genética , Solo/análise
16.
J Fish Biol ; 81(5): 1763-72, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23020574

RESUMO

Genetic variation and divergence among samples of Chilean hake Merluccius gayi, from three localities off the coast of Chile and one locality off the coast of northern Peru, were assessed using sequences from the control region of mitochondrial DNA. Homogeneity tests revealed occurrence of at least three distinct genetic stocks of M. gayi within the region sampled. Factors potentially contributing to genetic divergence among M. gayi probably include hydrodynamics and behaviour.


Assuntos
DNA Mitocondrial/genética , Gadiformes/classificação , Gadiformes/genética , Variação Genética , Animais , Chile , Genética Populacional , Haplótipos , Dados de Sequência Molecular , Peru , Especificidade da Espécie
17.
Eur J Pharm Biopharm ; 181: 239-248, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36384197

RESUMO

Enhancement of skin permeation of drugs is affected by the simultaneous co-permeation of excipients that hinder the predictivity of in vitro tests. The collaborative effects of two permeation enhancers (ethanol and d-limonene) of a lipophilic drug (alprazolam) have been simultaneously assessed in human skin under different in vitro conditions: integrated setups of diffusion cell experiments with selective concentration gradients of permeants (asymmetric) or without (symmetric) have been combined with coadministration dosages (all-in-one) at different concentrations or short-time skin pretreatment to scrutiny this mutual performance. Findings: Drug permeation is increased under moderated supersaturation but reaches a stationary level above 33 % of its solubility. Ethanol in absence of a concentration gradient increases ca.5 times basal drug permeation. Limonene until 20 % permeates human skin proportionally to its donor concentration but its effect does not depend on ethanol in symmetric conditions and is based on skin imbibition rather than on a carry-on effect. Simultaneous permeation of ethanol and limonene reaches a stationary state after 1.5 h, enough time to achieve maximal enhancement of alprazolam permeation. Additive enhancement is based on ethanol solubilisation maximized by skin saturation of terpene. Complementary analyses of skin disruption published in the literature are in line with these assessments and consolidate them.


Assuntos
Etanol , Excipientes , Humanos , Limoneno
18.
Rev Neurol ; 72(5): 168-176, 2021 Mar 01.
Artigo em Espanhol | MEDLINE | ID: mdl-33616199

RESUMO

INTRODUCTION: Fetal alcohol spectrum disorder (FASD) is the leading known and preventable cause of intellectual disability in the western world, affecting up to 1-5% of the population. It is considered an underdiagnosed and undertreated disorder, with few psychological interventions with empirical evidence. AIM: To review all the studies published to date on the psychological treatment of FASD throughout life. A bibliographic search was carried out using the MEDLINE, PsychINFO, PubMed and Cochrane Library databases using the terms 'fetal alcohol syndrome disorder' AND 'cognitive behavioral intervention' OR 'psychological intervention' OR 'psychological treatment' OR 'therapy' OR 'psychotherapy'. The review included published works which evaluate the efficacy of psychological treatments for these patients. DEVELOPMENT: Twenty published studies met the inclusion criteria. The treatments were classified according to the type of intervention: emotional and behavioral regulation, social skills training and family interventions for patients with FASD. CONCLUSIONS: The results indicate that psychological treatments focused on emotional and behavioral regulation, social skills training and family interventions are the most evidenced treatments for these patients. These treatments are based on cognitive-behavioral principles and include school-age children. However, more research is needed on psychological interventions for adults with FASD. Despite the progress in psychological interventions for FASD, the research still reflects highlighted limitations.


TITLE: Intervenciones psicológicas del trastorno del espectro alcohólico fetal a lo largo del ciclo vital.Introducción. El trastorno del espectro alcohólico fetal (TEAF) es la principal causa conocida y prevenible de discapacidad intelectual en el mundo occidental y afecta hasta al 1-5% de la población. Se considera un trastorno infradiagnosticado e infratratado, y las intervenciones psicológicas con evidencia empírica son escasas. Objetivo. Revisar los estudios publicados hasta el momento sobre tratamiento psicológico del TEAF a lo largo de la vida. Se realizó una búsqueda bibliográfica mediante las bases de datos de Medline, PsychINFO, PubMed y Cochrane Library usando los términos 'fetal alcohol syndrome disorder' AND 'cognitive behavioral intervention' OR 'psychological intervention' OR 'psychological treatment' OR 'therapy' OR 'psychotherapy'. Se incluyeron los trabajos publicados que evaluaran la eficacia de tratamientos psicológicos para estos pacientes. Desarrollo. Cumplieron los criterios de inclusión 20 estudios publicados. Los tratamientos se clasificaron en función del tipo de intervención: la regulación emocional y conductual, el entrenamiento en habilidades sociales y las intervenciones familiares. Conclusiones. Los resultados indican que los tratamientos psicológicos dirigidos a trabajar la regulación emocional y conductual, el entrenamiento en habilidades sociales y las intervenciones familiares son los que tienen mayor evidencia en el tratamiento para el TEAF. La mayoría se basa en principios cognitivo-conductuales y a niños de edad escolar, y son escasas todavía las investigaciones de tratamientos para adultos con TEAF. A pesar del progreso en las intervenciones psicológicas para el TEAF, la investigación aún refleja marcadas limitaciones.


Assuntos
Transtornos do Espectro Alcoólico Fetal/terapia , Intervenção Psicossocial , Humanos , Longevidade
19.
J Atten Disord ; 25(7): 933-941, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-31409171

RESUMO

Objective: To evaluate the association between prematurity (by the gestational week [gw]) and ADHD during childhood. Method: Observational, matched cohort study using data from children born in a tertiary-level hospital (Hospital Universitari Vall d'Hebron, Catalonia, Spain) during 1995-2007 and data from the Information System for the Development of Research in Primary Health Care (SIDIAP database, Catalonia, Spain). Results: Prevalence of ADHD increases as gestational age decreases, 12.7% for those born ≤28 gw, compared to 3.2% for those born after the 37 gw. The risk of developing ADHD in the non-premature children tends to increase as the gw decreases (35-36 gw, hazard ratio [HR] = 1.70, 95% confidence interval [CI] [1.19, 2.44]; 33-34 gw, HR = 3.38, 95% CI [2.08, 5.50]; 29-32 gw, HR = 2.37, 95% CI [1.54, 3.63]; and ≤28 gw, HR = 5.57, 95% CI [2.49, 12.46]) Conclusion: Being born preterm is associated with a risk of developing ADHD, also in late preterm children (35-36 gw). Attention when taking care of these infants regarding their mental health must be made.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Criança , Estudos de Coortes , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido de Baixo Peso , Recém-Nascido , Gravidez , Espanha/epidemiologia
20.
Neuropharmacology ; 187: 108490, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33607146

RESUMO

3,4-Methylenedioxymethamphetamine (MDMA) is an amphetamine derivative that has been shown to produce serotonergic damage in the brains of primates, including humans, and of rats. Tryptophan, the precursor of serotonin, is primarily degraded through the kynurenine (KYN) pathway, producing among others KYN, the main metabolite of this route. KYN has been reported as an endogenous agonist of the aryl hydrocarbon receptor (AhR), a transcription factor involved in several neurological functions. This study aims to determine the effect of MDMA on the KYN pathway and on AhR activity and to establish their role in the long-term serotonergic neurotoxicity induced by the drug in rats. Our results show that MDMA induces the activation of the KYN pathway, mediated by hepatic tryptophan 2,3-dioxygenase (TDO). MDMA also activated AhR as evidenced by increased AhR nuclear translocation and CYP1B1 mRNA expression. Autoradiographic quantification of serotonin transporters showed that both the TDO inhibitor 680C91 and the AhR antagonist CH-223191 potentiated the neurotoxicity induced by MDMA, while administration of exogenous l-kynurenine or of the AhR positive modulator 3,3'-diindolylmethane (DIM) partially prevented the serotonergic damage induced by the drug. The results demonstrate for the first time that MDMA increases KYN levels and AhR activity, and these changes appear to play a role in limiting the neurotoxicity induced by the drug. This work provides a better understanding of the physiological mechanisms that attenuate the brain damage induced by MDMA and identify modulation of the KYN pathway and of AhR as potential therapeutic strategies to limit the negative effects of MDMA.


Assuntos
Hipocampo/efeitos dos fármacos , Cinurenina/metabolismo , N-Metil-3,4-Metilenodioxianfetamina/toxicidade , Receptores de Hidrocarboneto Arílico/efeitos dos fármacos , Serotoninérgicos/toxicidade , Triptofano Oxigenase/efeitos dos fármacos , Animais , Autorradiografia , Hipocampo/metabolismo , Cinurenina/farmacologia , Síndromes Neurotóxicas , Ratos , Receptores de Hidrocarboneto Arílico/antagonistas & inibidores , Receptores de Hidrocarboneto Arílico/metabolismo , Serotonina , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Triptofano Oxigenase/antagonistas & inibidores , Triptofano Oxigenase/metabolismo
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