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1.
Genes Dev ; 34(9-10): 715-729, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32217665

RESUMO

Covalent chemical modifications of cellular RNAs directly impact all biological processes. However, our mechanistic understanding of the enzymes catalyzing these modifications, their substrates and biological functions, remains vague. Amongst RNA modifications N6-methyladenosine (m6A) is widespread and found in messenger (mRNA), ribosomal (rRNA), and noncoding RNAs. Here, we undertook a systematic screen to uncover new RNA methyltransferases. We demonstrate that the methyltransferase-like 5 (METTL5) protein catalyzes m6A in 18S rRNA at position A1832 We report that absence of Mettl5 in mouse embryonic stem cells (mESCs) results in a decrease in global translation rate, spontaneous loss of pluripotency, and compromised differentiation potential. METTL5-deficient mice are born at non-Mendelian rates and develop morphological and behavioral abnormalities. Importantly, mice lacking METTL5 recapitulate symptoms of patients with DNA variants in METTL5, thereby providing a new mouse disease model. Overall, our biochemical, molecular, and in vivo characterization highlights the importance of m6A in rRNA in stemness, differentiation, development, and diseases.


Assuntos
Diferenciação Celular/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Adenosina/análogos & derivados , Adenosina/metabolismo , Animais , Camundongos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/enzimologia , Mutação , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Biossíntese de Proteínas/genética , RNA Ribossômico 18S/metabolismo
2.
Nucleic Acids Res ; 52(D1): D545-D551, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37971316

RESUMO

Antibodies are key proteins of the adaptive immune system, and there exists a large body of academic literature and patents dedicated to their study and concomitant conversion into therapeutics, diagnostics, or reagents. These documents often contain extensive functional characterisations of the sets of antibodies they describe. However, leveraging these heterogeneous reports, for example to offer insights into the properties of query antibodies of interest, is currently challenging as there is no central repository through which this wide corpus can be mined by sequence or structure. Here, we present PLAbDab (the Patent and Literature Antibody Database), a self-updating repository containing over 150,000 paired antibody sequences and 3D structural models, of which over 65 000 are unique. We describe the methods used to extract, filter, pair, and model the antibodies in PLAbDab, and showcase how PLAbDab can be searched by sequence, structure, or keyword. PLAbDab uses include annotating query antibodies with potential antigen information from similar entries, analysing structural models of existing antibodies to identify modifications that could improve their properties, and facilitating the compilation of bespoke datasets of antibody sequences/structures that bind to a specific antigen. PLAbDab is freely available via Github (https://github.com/oxpig/PLAbDab) and as a searchable webserver (https://opig.stats.ox.ac.uk/webapps/plabdab/).


Assuntos
Anticorpos , Bases de Dados Factuais , Anticorpos/química , Anticorpos/genética , Antígenos/metabolismo , Modelos Moleculares , Patentes como Assunto , Internet
3.
J Neurosci ; 44(24)2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38670804

RESUMO

The 40 Hz auditory steady-state response (ASSR), an oscillatory brain response to periodically modulated auditory stimuli, is a promising, noninvasive physiological biomarker for schizophrenia and related neuropsychiatric disorders. The 40 Hz ASSR might be amplified by synaptic interactions in cortical circuits, which are, in turn, disturbed in neuropsychiatric disorders. Here, we tested whether the 40 Hz ASSR in the human auditory cortex depends on two key synaptic components of neuronal interactions within cortical circuits: excitation via N-methyl-aspartate glutamate (NMDA) receptors and inhibition via gamma-amino-butyric acid (GABA) receptors. We combined magnetoencephalography (MEG) recordings with placebo-controlled, low-dose pharmacological interventions in the same healthy human participants (13 males, 7 females). All participants exhibited a robust 40 Hz ASSR in auditory cortices, especially in the right hemisphere, under a placebo. The GABAA receptor-agonist lorazepam increased the amplitude of the 40 Hz ASSR, while no effect was detectable under the NMDA blocker memantine. Our findings indicate that the 40 Hz ASSR in the auditory cortex involves synaptic (and likely intracortical) inhibition via the GABAA receptor, thus highlighting its utility as a mechanistic signature of cortical circuit dysfunctions involving GABAergic inhibition.


Assuntos
Córtex Auditivo , Potenciais Evocados Auditivos , Neurônios GABAérgicos , Magnetoencefalografia , Humanos , Córtex Auditivo/efeitos dos fármacos , Córtex Auditivo/fisiologia , Masculino , Feminino , Adulto , Potenciais Evocados Auditivos/efeitos dos fármacos , Potenciais Evocados Auditivos/fisiologia , Neurônios GABAérgicos/fisiologia , Neurônios GABAérgicos/efeitos dos fármacos , Adulto Jovem , Inibição Neural/fisiologia , Inibição Neural/efeitos dos fármacos , Estimulação Acústica
4.
J Neurosci ; 44(26)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38760163

RESUMO

Aging is accompanied by a decline of working memory, an important cognitive capacity that involves stimulus-selective neural activity that persists after stimulus presentation. Here, we unraveled working memory dynamics in older human adults (male and female) including those diagnosed with mild cognitive impairment (MCI) using a combination of behavioral modeling, neuropsychological assessment, and MEG recordings of brain activity. Younger adults (male and female) were studied with behavioral modeling only. Participants performed a visuospatial delayed match-to-sample task under systematic manipulation of the delay and distance between sample and test stimuli. Their behavior (match/nonmatch decisions) was fit with a computational model permitting the dissociation of noise in the internal operations underlying the working memory performance from a strategic decision threshold. Task accuracy decreased with delay duration and sample/test proximity. When sample/test distances were small, older adults committed more false alarms than younger adults. The computational model explained the participants' behavior well. The model parameters reflecting internal noise (not decision threshold) correlated with the precision of stimulus-selective cortical activity measured with MEG during the delay interval. The model uncovered an increase specifically in working memory noise in older compared with younger participants. Furthermore, in the MCI group, but not in the older healthy controls, internal noise correlated with the participants' clinically assessed cognitive integrity. Our results are consistent with the idea that the stability of working memory contents deteriorates in aging, in a manner that is specifically linked to the overall cognitive integrity of individuals diagnosed with MCI.


Assuntos
Envelhecimento , Encéfalo , Magnetoencefalografia , Memória de Curto Prazo , Humanos , Masculino , Feminino , Memória de Curto Prazo/fisiologia , Idoso , Envelhecimento/fisiologia , Envelhecimento/psicologia , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Encéfalo/fisiologia , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/psicologia , Cognição/fisiologia , Testes Neuropsicológicos , Idoso de 80 Anos ou mais , Modelos Neurológicos
5.
Arch Toxicol ; 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39158710

RESUMO

Seas worldwide are threatened by an emerging source of pollution as millions of tons of warfare materials were dumped after the World Wars. As their metal shells are progressively corroding, energetic compounds (EC) leak out and distribute in the marine environment. EC are taken up by aquatic organisms and pose a threat to both the marine ecosphere and the human seafood consumer because of their toxicity and potential carcinogenicity. Here, sediment samples and fish from different locations in the German North Sea of Lower Saxony were examined to determine whether EC transfer to fish living close to munition dumping areas. EC were found in sediments with a maximum concentration of 1.5 ng/kg. All analyzed fish muscle tissues/fillets and bile samples were positive for EC detection. In bile, the max. EC concentrations ranged between 0.25 and 1.25 ng/mL. Interestingly, while detected TNT metabolites in the muscle tissues were in concentrations of max. 1 ng/g (dry weight), TNT itself was found in concentrations of up to 4 ng/g (dry weight). As we found considerable higher amounts of non-metabolized TNT in the fish muscle, rather than TNT metabolites, we conclude an additional absorption route of EC into fish other than per diet. This is the first study to detect EC in the edible parts of fish caught randomly in the North Sea.

6.
Eur J Appl Physiol ; 124(8): 2427-2438, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38546844

RESUMO

PURPOSE: Power output at the moderate-to-heavy-intensity transition decreases during prolonged exercise, and resilience to this has been termed 'durability'. The purpose of this study was to assess the relationship between durability and the effect of prolonged exercise on severe-intensity performance, and explore intramuscular correlates of durability. METHODS: On separate days, 13 well-trained cyclists and triathletes (V̇O2peak, 57.3 ± 4.8 mL kg-1 min-1; training volume, 12 ± 2.1 h week-1) undertook an incremental test and 5-min time trial (TT) to determine power output at the first ventilatory threshold (VT1) and severe-intensity performance, with and without 150-min of prior moderate-intensity cycling. A single resting vastus lateralis microbiopsy was obtained. RESULTS: Prolonged exercise reduced power output at VT1 (211 ± 40 vs. 198 ± 39 W, ∆ -13 ± 16 W, ∆ -6 ± 7%, P = 0.013) and 5-min TT performance (333 ± 75 vs. 302 ± 63 W, ∆ -31 ± 41 W, ∆ -9 ± 10%, P = 0.017). The reduction in 5-min TT performance was significantly associated with durability of VT1 (rs = 0.719, P = 0.007). Durability of VT1 was not related to vastus lateralis carnosine content, citrate synthase activity, or complex I activity (P > 0.05). CONCLUSION: These data provide the first direct support that durability of the moderate-to-heavy-intensity transition is an important performance parameter, as more durable athletes exhibited smaller reductions in 5-min TT performance following prolonged exercise. We did not find relationships between durability and vastus lateralis carnosine content, citrate synthase activity, or complex I activity.


Assuntos
Consumo de Oxigênio , Humanos , Masculino , Adulto , Consumo de Oxigênio/fisiologia , Exercício Físico/fisiologia , Ciclismo/fisiologia , Desempenho Atlético/fisiologia , Resistência Física/fisiologia , Músculo Esquelético/fisiologia , Carnosina/metabolismo , Músculo Quadríceps/fisiologia , Músculo Quadríceps/metabolismo , Feminino
7.
J Med Internet Res ; 26: e52118, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598286

RESUMO

BACKGROUND: Children whose parents have alcohol use problems are at an increased risk of several negative consequences, such as poor school performance, an earlier onset of substance use, and poor mental health. Many would benefit from support programs, but the figures reveal that only a small proportion is reached by existing support. Digital interventions can provide readily accessible support and potentially reach a large number of children. Research on digital interventions aimed at this target group is scarce. We have developed a novel digital therapist-assisted self-management intervention targeting adolescents whose parents had alcohol use problems. This program aims to strengthen coping behaviors, improve mental health, and decrease alcohol consumption in adolescents. OBJECTIVE: This study aims to examine the effectiveness of a novel web-based therapist-assisted self-management intervention for adolescents whose parents have alcohol use problems. METHODS: Participants were recruited on the internet from social media and websites containing health-related information about adolescents. Possible participants were screened using the short version of the Children of Alcoholics Screening Test-6. Eligible participants were randomly allocated to either the intervention group (n=101) or the waitlist control group (n=103), and they were unblinded to the condition. The assessments, all self-assessed, consisted of a baseline and 2 follow-ups after 2 and 6 months. The primary outcome was the Coping With Parents Abuse Questionnaire (CPAQ), and secondary outcomes were the Center for Epidemiological Studies Depression Scale, Alcohol Use Disorders Identification Test (AUDIT-C), and Ladder of Life (LoL). RESULTS: For the primary outcome, CPAQ, a small but inconclusive treatment effect was observed (Cohen d=-0.05 at both follow-up time points). The intervention group scored 38% and 46% lower than the control group on the continuous part of the AUDIT-C at the 2- and 6-month follow-up, respectively. All other between-group comparisons were inconclusive at either follow-up time point. Adherence was low, as only 24% (24/101) of the participants in the intervention group completed the intervention. CONCLUSIONS: The findings were inconclusive for the primary outcome but demonstrate that a digital therapist-assisted self-management intervention may contribute to a reduction in alcohol consumption. These results highlight the potential for digital interventions to reach a vulnerable, hard-to-reach group of adolescents but underscore the need to develop more engaging support interventions to increase adherence. TRIAL REGISTRATION: ISRCTN Registry ISRCTN41545712; https://www.isrctn.com/ISRCTN41545712?q=ISRCTN41545712. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.1186/1471-2458-12-35.


Assuntos
Alcoolismo , Adolescente , Humanos , Criança , Etanol , Consumo de Bebidas Alcoólicas , Capacidades de Enfrentamento , Internet , Pais
8.
Inorg Chem ; 62(33): 13597-13607, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37562775

RESUMO

Numerous studies have explored the kinetics of light-induced charge separation and thermal charge recombination in donor-acceptor compounds, but quantum efficiencies have rarely been investigated. Here, we report on two essentially isomeric molecular triads, both comprising a π-extended tetrathiafulvalene (ExTTF) donor, a ruthenium(II)-based photosensitizer, and a naphthalene diimide (NDI) acceptor. The key difference between the two triads is how the NDI acceptor is connected. Linkage at the NDI core provides stronger electronic coupling to the other molecular components than connection via the nitrogen atoms of NDI. This change in molecular connectivity is expected to accelerate both energy-storing charge separation and energy-wasting charge recombination processes, but it is not a priori clear how this will affect the triad's ability to store photochemical energy; any gain resulting from faster charge separation could potentially be (over)compensated by losses through accelerated charge recombination. The new key insight emerging from our study is that the quantum yield for the formation of a long-lived charge-separated state increases by a factor of 5 when going from nitrogen- to core-connected NDI, providing the important proof of concept that better molecular connectivity indeed enables more efficient photochemical energy storage. The physical origin of this behavior seems to root in different orbital connectivity pathways for charge separation and charge recombination, as well as in differences in the relevant orbital interactions depending on NDI connection. Our work provides guidelines for how to discriminate between energy-storing and energy-wasting electron transfer reactions in order to improve the quantum yields for photochemical energy storage and solar energy conversion.

9.
Environ Sci Technol ; 57(48): 20169-20181, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37933956

RESUMO

Submerged munitions from World War I and II are threatening human activities in the oceans, including fisheries and shipping or the construction of pipelines and offshore facilities. To avoid unforeseen explosions, remotely controlled "blast-in-place" (BiP) operations are a common practice worldwide. However, after underwater BiP detonations, the toxic and carcinogenic energetic compounds (ECs) will not completely combust but rather distribute within the marine ecosphere. To shed light on this question, two comparable World War II mines in Denmark's Sejerø Bay (Baltic Sea) were blown up by either low-order or high-order BiP operations by the Royal Danish Navy. Water and sediment samples were taken before and immediately after the respective BiP operation and analyzed for the presence of ECs with sensitive GC-MS/MS and LC-MS/MS technology. EC concentrations increased after high-order BiP detonations up to 353 ng/L and 175 µg/kg in water and sediment, respectively, while low-order BiP detonations resulted in EC water and sediment concentrations up to 1,000,000 ng/L (1 mg/L) and >10,000,000 µg/kg (>10 g/kg), respectively. Our studies provide unequivocal evidence that BiP operations in general lead to a significant increase of contamination of the marine environment and ecotoxicological risk with toxic ECs. Moreover, as compared to high-order BiP detonations, low-order BiP detonations resulted in a several 1000-fold higher burden on the marine environment.


Assuntos
Explosões , Poluentes Químicos da Água , Humanos , Espectrometria de Massas em Tandem , Cromatografia Líquida , Oceanos e Mares , Água , Poluentes Químicos da Água/toxicidade
10.
J Am Chem Soc ; 144(31): 14181-14194, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35913126

RESUMO

The photoredox activity of well-known RuII complexes stems from metal-to-ligand charge transfer (MLCT) excited states, in which a ligand-based electron can initiate chemical reductions and a metal-centered hole can trigger oxidations. CrIII polypyridines show similar photoredox properties, although they have fundamentally different electronic structures. Their photoactive excited state is of spin-flip nature, differing from the electronic ground state merely by a change of one electron spin, but with otherwise identical d-orbital occupancy. We find that the driving-force dependence for photoinduced electron transfer from 10 different donors to a spin-flip excited state of a CrIII complex is very similar to that for a RuII polypyridine, and thereby validate the concept of estimating the redox potential of d3 spin-flip excited states in analogous manner as for the MLCT states of d6 compounds. Building on this insight, we use our CrIII complex for photocatalytic reactions not previously explored with this compound class, including the aerobic bromination of methoxyaryls, oxygenation of 1,1,2,2-tetraphenylethylene, aerobic hydroxylation of arylboronic acids, and the vinylation of N-phenyl pyrrolidine. This work contributes to understanding the fundamental photochemical properties of first-row transition-metal complexes in comparison to well-explored precious-metal-based photocatalysts.

11.
Hum Brain Mapp ; 43(4): 1265-1279, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34816533

RESUMO

While functional magnetic resonance imaging (fMRI) at ultra-high field (7 T) promises a general increase in sensitivity compared to lower field strengths, the benefits may be most pronounced for specific applications. The current study aimed to evaluate the relative benefit of 7 over 3 T fMRI for the assessment of responses evoked in different brain regions by a well-controlled cognitive task. At 3 and 7 T, the same participants made challenging perceptual decisions about visual motion combined with monetary rewards for correct choices. Previous work on this task has extensively characterized the underlying cognitive computations and single-cell responses in cortical and subcortical structures. We quantified the evoked fMRI responses in extrastriate visual cortical areas, the striatum, and the brainstem during the decision interval and the post-feedback interval of the task. The dependence of response amplitudes on field strength during the decision interval differed between cortical, striatal, and brainstem regions, with a generally bigger 7 versus 3 T benefit in subcortical structures. We also found stronger responses during relatively easier than harder decisions at 7 T for dopaminergic midbrain nuclei, in line with reward expectation. Our results demonstrate the potential of 7 T fMRI for illuminating the contribution of small brainstem nuclei to the orchestration of cognitive computations in the human brain.


Assuntos
Tronco Encefálico , Corpo Estriado , Tomada de Decisões/fisiologia , Neuroimagem Funcional , Imageamento por Ressonância Magnética , Percepção de Movimento/fisiologia , Recompensa , Córtex Visual , Adulto , Tronco Encefálico/diagnóstico por imagem , Tronco Encefálico/fisiologia , Corpo Estriado/diagnóstico por imagem , Corpo Estriado/fisiologia , Feminino , Humanos , Masculino , Córtex Visual/diagnóstico por imagem , Córtex Visual/fisiologia , Adulto Jovem
12.
Cereb Cortex ; 31(7): 3565-3578, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-33822917

RESUMO

Central to human and animal cognition is the ability to learn from feedback in order to optimize future rewards. Such a learning signal might be encoded and broadcasted by the brain's arousal systems, including the noradrenergic locus coeruleus. Pupil responses and the positive slow wave component of event-related potentials reflect rapid changes in the arousal level of the brain. Here, we ask whether and how these variables may reflect surprise: the mismatch between one's expectation about being correct and the outcome of a decision, when expectations fluctuate due to internal factors (e.g., engagement). We show that during an elementary decision task in the face of uncertainty both physiological markers of phasic arousal reflect surprise. We further show that pupil responses and slow wave event-related potential are unrelated to each other and that prediction error computations depend on feedback awareness. These results further advance our understanding of the role of central arousal systems in decision-making under uncertainty.


Assuntos
Nível de Alerta/fisiologia , Encéfalo/fisiologia , Tomada de Decisões/fisiologia , Potenciais Evocados/fisiologia , Feedback Formativo , Reflexo Pupilar/fisiologia , Adolescente , Eletroencefalografia , Feminino , Humanos , Aprendizagem , Masculino , Pupila/fisiologia , Incerteza , Adulto Jovem
13.
Eur Addict Res ; 28(2): 155-160, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34839293

RESUMO

BACKGROUND: Monitoring emerging trends in the increasingly dynamic European drug market is vital; however, information on change at the individual level is scarce. In the current study, we investigated changes in drug use over 12 months in European nightlife attendees. METHOD: In this longitudinal online survey, changes in substances used, use frequency in continued users, and relative initiation of use at follow-up were assessed for 20 different substances. To take part, participants had to be aged 18-34 years; be from Belgium, Italy, the Netherlands, Sweden, or the UK; and have attended at least 6 electronic music events in the past 12 months at baseline. Of 8,045 volunteers at baseline, 2,897 completed the survey at both time points (36% follow-up rate), in 2017 and 2018. RESULTS: The number of people using ketamine increased by 21% (p < 0.001), and logarithmized frequency of use in those continuing use increased by 15% (p < 0.001; 95% CI: 0.07-0.23). 4-Fluoroamphetamine use decreased by 27% (p < 0.001), and logarithmized frequency of use in continuing users decreased by 15% (p < 0.001, 95% CI: -0.48 to -0.23). The drugs with the greatest proportion of relative initiation at follow-up were synthetic cannabinoids (73%, N = 30), mephedrone (44%, N = 18), alkyl nitrites (42%, N = 147), synthetic dissociatives (41%, N = 15), and prescription opioids (40%, N = 48). CONCLUSIONS: In this European nightlife sample, ketamine was found to have the biggest increase in the past 12 months, which occurred alongside an increase in frequency of use in continuing users. The patterns of uptake and discontinuation of alkyl nitrates, novel psychoactive substances, and prescription opioids provide new information that has not been captured by existing cross-sectional surveys. These findings demonstrate the importance of longitudinal assessments of drug use and highlight the dynamic nature of the European drug landscape.


Assuntos
Transtornos Relacionados ao Uso de Substâncias , Adolescente , Adulto , Bélgica/epidemiologia , Estudos Transversais , Humanos , Estudos Longitudinais , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Suécia , Adulto Jovem
14.
J Neurophysiol ; 125(4): 1468-1481, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33689508

RESUMO

Many decisions result from the accumulation of decision-relevant information (evidence) over time. Even when maximizing decision accuracy requires weighting all the evidence equally, decision-makers often give stronger weight to evidence occurring early or late in the evidence stream. Here, we show changes in such temporal biases within participants as a function of intermittent judgments about parts of the evidence stream. Human participants performed a decision task that required a continuous estimation of the mean evidence at the end of the stream. The evidence was either perceptual (noisy random dot motion) or symbolic (variable sequences of numbers). Participants also reported a categorical judgment of the preceding evidence half-way through the stream in one condition or executed an evidence-independent motor response in another condition. The relative impact of early versus late evidence on the final estimation flipped between these two conditions. In particular, participants' sensitivity to late evidence after the intermittent judgment, but not the simple motor response, was decreased. Both the intermittent response as well as the final estimation reports were accompanied by nonluminance-mediated increases of pupil diameter. These pupil dilations were bigger during intermittent judgments than simple motor responses and bigger during estimation when the late evidence was consistent than inconsistent with the initial judgment. In sum, decisions activate pupil-linked arousal systems and alter the temporal weighting of decision evidence. Our results are consistent with the idea that categorical choices in the face of uncertainty induce a change in the state of the neural circuits underlying decision-making.NEW & NOTEWORTHY The psychology and neuroscience of decision-making have extensively studied the accumulation of decision-relevant information toward a categorical choice. Much fewer studies have assessed the impact of a choice on the processing of subsequent information. Here, we show that intermittent choices during a protracted stream of input reduce the sensitivity to subsequent decision information and transiently boost arousal. Choices might trigger a state change in the neural machinery for decision-making.


Assuntos
Tomada de Decisões/fisiologia , Julgamento/fisiologia , Conceitos Matemáticos , Percepção de Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Psicofísica , Percepção Espacial/fisiologia , Adulto , Humanos , Pupila/fisiologia , Adulto Jovem
15.
PLoS Biol ; 16(2): e2003453, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29420565

RESUMO

The ascending modulatory systems of the brain stem are powerful regulators of global brain state. Disturbances of these systems are implicated in several major neuropsychiatric disorders. Yet, how these systems interact with specific neural computations in the cerebral cortex to shape perception, cognition, and behavior remains poorly understood. Here, we probed into the effect of two such systems, the catecholaminergic (dopaminergic and noradrenergic) and cholinergic systems, on an important aspect of cortical computation: its intrinsic variability. To this end, we combined placebo-controlled pharmacological intervention in humans, recordings of cortical population activity using magnetoencephalography (MEG), and psychophysical measurements of the perception of ambiguous visual input. A low-dose catecholaminergic, but not cholinergic, manipulation altered the rate of spontaneous perceptual fluctuations as well as the temporal structure of "scale-free" population activity of large swaths of the visual and parietal cortices. Computational analyses indicate that both effects were consistent with an increase in excitatory relative to inhibitory activity in the cortical areas underlying visual perceptual inference. We propose that catecholamines regulate the variability of perception and cognition through dynamically changing the cortical excitation-inhibition ratio. The combined readout of fluctuations in perception and cortical activity we established here may prove useful as an efficient and easily accessible marker of altered cortical computation in neuropsychiatric disorders.


Assuntos
Catecolaminas/fisiologia , Córtex Cerebral/fisiologia , Percepção Visual/fisiologia , Inibidores da Captação Adrenérgica/farmacologia , Cloridrato de Atomoxetina/farmacologia , Mapeamento Encefálico , Córtex Cerebral/efeitos dos fármacos , Humanos , Magnetoencefalografia/métodos , Modelos Neurológicos , Estimulação Luminosa , Placebos , Psicofísica
16.
Nord J Psychiatry ; 75(2): 155-158, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32852242

RESUMO

AIMS: The Children of Alcoholics Screening Test (CAST-6) is a brief screening instrument developed to identify children with parents having problematic alcohol use. The aim of this study was to evaluate the psychometric properties of the CAST-6 among adolescents aged 15-18 years, and also to identify an optimal cut-off score for this age group. METHODS: A total of 3000 15 to18 year-olds were randomly selected from a register of postal addresses in Sweden. An invitation letter, including access information to the electronic questionnaire, was sent out by regular mail and 1450 adolescents responded with baseline data. Test-retest reliability within a 2-3-week period was calculated based on the 111 respondents who answered the same questionnaire twice. To determine an optimal cut-off score, a small treatment-seeking sample (n = 22) was recruited from a support group agency to be used as a reference group. RESULTS: The six items of the CAST-6 screening test loaded onto one latent factor with good internal consistency (alpha = 0.88), and excellent test-retest reliability (ICC = 0.93, 95% CI 0.90-0.95). The optimal cut-off score among adolescents was 2 points with a sensitivity of 55% and specificity of 79% (AUROC = 0.71, 95% CI 0.58-0.83). CONCLUSIONS: The CAST-6 has good to excellent psychometric properties among adolescents. The identified optimal cut-off score of 2 points should be treated with caution due to study limitations. The CAST-6 can be used in various settings to identify a vulnerable at-risk group of children and adolescents that may be in need of support.


Assuntos
Alcoólicos , Adolescente , Criança , Humanos , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários , Suécia
17.
J Exp Biol ; 223(Pt 22)2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33037110

RESUMO

Oxidative stress, which occurs from an imbalance of reactive oxygen and nitrogen species (RONS) and both endogenous and exogenous antioxidants, promotes aging and underlies sex-specific differences in longevity and susceptibility to age-related neurodegeneration. Recent evidence suggests that curcumin, a yellow pigment derived from turmeric and shown to exhibit antioxidant properties as a RONS scavenger, influences the regulation of genetic elements in endogenous antioxidant pathways. To investigate the role of curcumin in sex-specific in vivo responses to oxidative stress, Drosophila were reared on media supplemented with 0.25, 2.5 or 25 mmol l-1 curcuminoids (consisting of curcumin, demethoxycurcumin and bisdemethoxycurcumin) and resistance to oxidative stress and neural parameters were assessed. High levels of curcuminoids exhibited two sex-specific effects: protection from hydrogen peroxide as an oxidative stressor and alterations in turning rate in an open field. Taken together, these results suggest that the influence of curcuminoids as antioxidants probably relies on changes in gene expression and that sexual dimorphism exists in the in vivo response to curcuminoids.


Assuntos
Curcumina , Animais , Antioxidantes , Curcumina/farmacologia , Drosophila melanogaster/genética , Feminino , Masculino , Estresse Oxidativo , Espécies Reativas de Oxigênio
18.
J Org Chem ; 85(21): 13757-13771, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-32933246

RESUMO

The synthesis of shape-persistent organic cage compounds by the formation of imine bonds opens the possibility to realize cages of different sizes, geometries, topologies, and functions. It is generally assumed that the imine bond is rather chemically labile allowing a self-correction mechanism until thermodynamic equilibrium is reached, which is often the case if a cage is formed. However, there are some contradictory experimental data to this assumption. To get a deeper insight into the imine bond dynamics of covalent organic cages, we studied the formation and exchange of both dialdehydes and triamines of two different [2 + 3] imine cages with the aid of a deuterated dialdehyde molecular building block.

19.
Subst Use Misuse ; 55(13): 2116-2128, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32811266

RESUMO

BACKGROUND: Illicit drug use is common in nightlife settings and associated with various public health-related problems, making this an important arena for prevention. Purpose/objectives: To assess perceived prevalence of illicit drug use in the Stockholm nightlife setting, use of and attitudes toward illicit drugs among employees at licensed premises. Also, to make comparisons with two identical measurements from 2001 and 2007/08, and to explore potential differences related to own drug use, type of licensed premise, age or gender. Methods: Cross-sectional surveys were conducted at three time-points: 2001, 2007/08, and 2016/17, comprising employees at licensed premises in Stockholm participating in STAD's Responsible Beverage Service training program. A total of 665 persons (mean age 28 years, 53% women) were included in the 2016/2017 measurement. Results: A majority of the respondents reported having observed patrons intoxicated by illicit drugs in the last six months, and agreed that patrons intoxicated by illicit drugs should be asked to leave licensed premises. The belief that one had observed patrons intoxicated by illicit drugs was more common among respondents who had themselves been using illicit drugs during the last year, and also among employees at nightclubs. Furthermore, comparisons with previous time-points showed a significant increase in the proportion of employees using illicit drugs. Almost half of the respondents in the youngest age group (18-24 years) reported illicit drug use during the last year. Conclusions/importance: Observation and use of illicit drugs are common among employees in the Stockholm nightlife setting and has increased significantly during the past decade.


Assuntos
Drogas Ilícitas , Transtornos Relacionados ao Uso de Substâncias , Adolescente , Adulto , Consumo de Bebidas Alcoólicas , Estudos Transversais , Feminino , Humanos , Masculino , Percepção , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Adulto Jovem
20.
Nord J Psychiatry ; 74(1): 69-72, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31553246

RESUMO

Aim: To examine the extent to which structured action plans, i.e. collaborative individual plans (CIPs), used by professionals within the psychiatric care, substance use treatment services and social services, evaluate if clients have children, and if professionals take actions if clients do have children. According to Swedish law, a CIP should be established when a client is in need of care from more than one branch of the care network. Professionals who meet adult clients have the opportunity to identify children at risk. Including a question in the CIP on whether a client has a child is a good approach to identify children in need of support.Methods: Cross-sectional data from professionals were collected prior to attending a three-day CIP course. A total of 705 individuals (n = 797 invited) responded to the questionnaire.Results: More than 90% reported that they meet clients for whom a CIP should be established, and 52.6% of these (n = 346) were aware of an existing CIP template within their organization. Approximately 30% (n = 203) reported that this template included an item on whether the client has one or more children. Of these, a majority reported ensuring that the children receive adequate care (83.3%, n = 169), and that they follow up on the receipt of such care (62.6%, n = 125).Conclusions: The care network needs to implement CIPs to a higher degree, and CIP templates need to include items about the clients' children to ensure that children at risk are identified and thereby can receive adequate support.


Assuntos
Transtornos Mentais/terapia , Pais , Equipe de Assistência ao Paciente , Serviço Social , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
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