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1.
Neuropsychologia ; 193: 108760, 2024 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-38103681

RESUMO

While numerical skills are increasingly important in modern life, few interventions have been developed to support those with numeracy skills difficulties. Previous studies have demonstrated that applying transcranial Direct Current Stimulation (tDCS) can improve numerical skills. However, tDCS interventions designed to induce lasting changes typically involve reapplying brain-stimulation over several days. Repeated tDCS application can increase the risks associated with the procedure, as well as restricts the transferability of the method to a wider population, particularly those who may experience mobility issues, such as stroke survivors with acalculia. The current study investigated whether a single session of tDCS (anodal to right parietal lobe and cathodal to left parietal lobe), followed by four self-practice sessions without tDCS, could result in enhancement of numerical skills. Nineteen healthy adults (n = 10 tDCS, n = 9 sham control) implicitly learnt the magnitude association of nine arbitrary symbols, previously used by Cohen Kadosh et al. (2010). Numerical proficiency was assessed using number-to-space task, while automaticity was assessed with numerical Stroop. Results revealed that single-session tDCS had a significant effect on participants' accuracy on the number-to-space tasks, but not on the numerical Stroop task's congruity effect, implying automaticity may require longer practice. We conclude that a single session of tDCS should be considered as an avenue for interventions.


Assuntos
Estimulação Transcraniana por Corrente Contínua , Adulto , Humanos , Estimulação Transcraniana por Corrente Contínua/métodos , Aprendizagem , Lobo Parietal/fisiologia , Teste de Stroop , Eletrodos
2.
AJOB Neurosci ; 14(1): 13-15, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36524949
3.
Metallomics ; 14(9)2022 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-36066904

RESUMO

Queuosine (Q) is a conserved hypermodification of the wobble base of tRNA containing GUN anticodons but the physiological consequences of Q deficiency are poorly understood in bacteria. This work combines transcriptomic, proteomic and physiological studies to characterize a Q-deficient Escherichia coli K12 MG1655 mutant. The absence of Q led to an increased resistance to nickel and cobalt, and to an increased sensitivity to cadmium, compared to the wild-type (WT) strain. Transcriptomic analysis of the WT and Q-deficient strains, grown in the presence and absence of nickel, revealed that the nickel transporter genes (nikABCDE) are downregulated in the Q- mutant, even when nickel is not added. This mutant is therefore primed to resist to high nickel levels. Downstream analysis of the transcriptomic data suggested that the absence of Q triggers an atypical oxidative stress response, confirmed by the detection of slightly elevated reactive oxygen species (ROS) levels in the mutant, increased sensitivity to hydrogen peroxide and paraquat, and a subtle growth phenotype in a strain prone to accumulation of ROS.


Assuntos
Escherichia coli K12 , Nucleosídeo Q , Anticódon , Cádmio , Cobalto , Escherichia coli K12/genética , Escherichia coli K12/metabolismo , Homeostase , Peróxido de Hidrogênio , Níquel , Nucleosídeo Q/metabolismo , Estresse Oxidativo , Paraquat , Fenótipo , Proteômica , RNA de Transferência/genética , RNA de Transferência/metabolismo , Espécies Reativas de Oxigênio
4.
Animals (Basel) ; 12(16)2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36009713

RESUMO

Modern zoos strive to construct habitats which both enable and encourage animals to engage in species-specific behaviour, without compromising their visibility to visitors. Here, we present the findings of a within-zoo move to a custom-built exhibit (Islands at Chester Zoo, UK) with respect to the behaviour of four mammal species; the Sumatran orangutan (Pongo abelii), crested macaque (Macaca nigra), Malayan tapir (Tapirus indicus) and the Malayan sun bear (Helarctos malayanus). We used full activity budgets along with Compositional Data Analysis (CoDA) to gain insight into how the move to a more naturalistic exhibit influenced behaviour. Engagement in abnormal behaviour remained low during the study period for all four species, suggesting no adverse responses to the change in environment. Following the move, both the non-human primate species spent more time engaged in positive social interactions with conspecifics, highlighting the importance of social support during enclosure moves. Time spent visible to the public was largely unaffected by the enclosure move for the Sumatran orangutan, whilst the movement to a new environment increased visibility for the Malayan sun bear and decreased visibility for the crested macaque and Malayan tapir. We demonstrate the value of monitoring behaviour throughout the translocation of zoo-housed species and outline the positive behavioral impacts of providing individuals with naturalistic, species-appropriate environments.

5.
PLoS One ; 16(7): e0253185, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34288934

RESUMO

For most people, immersing their hands in water leads to wrinkling of the skin of the fingertips. This phenomenon is very striking, yet we know little about why it occurs. It has been proposed that the wrinkles act to distribute water away from the contact surfaces of the fingertip, meaning that wet objects can be grasped more readily. This study examined the coordination between the grip force used to hold an object and the load force exerted on it, when participants used dry or wrinkly fingers, or fingers that were wet but not wrinkly. The results showed that wrinkly fingers reduce the grip force needed to grip a wet object, bringing that force in line with what is needed for handling a dry object. The results suggest that enhancing grip force efficiency in watery environments is a possible adaptive reason for the development of wrinkly fingers.


Assuntos
Dedos , Força da Mão , Envelhecimento da Pele , Adolescente , Feminino , Força da Mão/fisiologia , Humanos , Imersão , Masculino , Envelhecimento da Pele/fisiologia , Água
7.
Nat Biotechnol ; 39(8): 978-988, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33859402

RESUMO

Current next-generation RNA-sequencing (RNA-seq) methods do not provide accurate quantification of small RNAs within a sample, due to sequence-dependent biases in capture, ligation and amplification during library preparation. We present a method, absolute quantification RNA-sequencing (AQRNA-seq), that minimizes biases and provides a direct, linear correlation between sequencing read count and copy number for all small RNAs in a sample. Library preparation and data processing were optimized and validated using a 963-member microRNA reference library, oligonucleotide standards of varying length, and RNA blots. Application of AQRNA-seq to a panel of human cancer cells revealed >800 detectable miRNAs that varied during cancer progression, while application to bacterial transfer RNA pools, with the challenges of secondary structure and abundant modifications, revealed 80-fold variation in tRNA isoacceptor levels, stress-induced site-specific tRNA fragmentation, quantitative modification maps, and evidence for stress-induced, tRNA-driven, codon-biased translation. AQRNA-seq thus provides a versatile means to quantitatively map the small RNA landscape in cells.


Assuntos
MicroRNAs , Alinhamento de Sequência/métodos , Análise de Sequência de RNA/métodos , Linhagem Celular Tumoral , Biblioteca Gênica , Humanos , MicroRNAs/química , MicroRNAs/genética , Neoplasias/genética , Neoplasias/metabolismo , RNA Bacteriano/química , RNA Bacteriano/genética , RNA de Transferência/química , RNA de Transferência/genética
8.
Eur J Neurosci ; 53(4): 996-1007, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32877015

RESUMO

The distance between the surface of the scalp and the surface of the grey matter of the brain is a key factor in determining the effective dose of non-invasive brain stimulation for an individual person. The highly folded nature of the cortical surface means that the depth of a particular brain area is likely to vary between individuals. The question addressed here is: what is the variability of this measure of cortical depth? Ninety-four anatomical MRI images were taken from the OASIS database. For each image, the minimum distance from each point in the grey matter to the scalp surface was determined. Transforming these estimates into standard space meant that the coefficient of variation could be determined across the sample. The results indicated that depth variability is high across the cortical surface, even when taking sulcal depth into account. This was true even for the primary visual and motor areas, which are often used in setting TMS dosage. The correlation of the depth of these areas and the depth of other brain areas was low. The results suggest that dose setting of TMS based on visual or evoked potentials may offer poor reliability, and that individual brain images should be used when targeting non-primary brain areas.


Assuntos
Potencial Evocado Motor , Córtex Motor , Mapeamento Encefálico , Humanos , Imageamento por Ressonância Magnética , Reprodutibilidade dos Testes , Estimulação Magnética Transcraniana
9.
RNA Biol ; 18(4): 563-575, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32893724

RESUMO

Protein synthesis rate and accuracy are tightly controlled by the cell and are essential for proteome homoeostasis (proteostasis); however, the full picture of how mRNA translational factors maintain protein synthesis accuracy and co-translational protein folding are far from being fully understood. To address this question, we evaluated the role of 70 yeast tRNA-modifying enzyme genes on protein aggregation and used mass spectrometry to identify the aggregated proteins. We show that modification of uridine at anticodon position 34 (U34) by the tRNA-modifying enzymes Elp1, Elp3, Sml3 and Trm9 is critical for proteostasis, the mitochondrial tRNA-modifying enzyme Slm3 plays a fundamental role in general proteostasis and that stress response proteins whose genes are enriched in codons decoded by tRNAs lacking mcm5U34, mcm5s2U34, ncm5U34, ncm5Um34, modifications are overrepresented in protein aggregates of the ELP1, SLM3 and TRM9 KO strains. Increased rates of amino acid misincorporation were also detected in these strains at protein sites that specifically mapped to the codons sites that are decoded by the hypomodified tRNAs, demonstrating that U34 tRNA modifications safeguard the proteome from translational errors, protein misfolding and proteotoxic stress.


Assuntos
Enzimas/genética , Agregados Proteicos/genética , Biossíntese de Proteínas/genética , RNA de Transferência/metabolismo , Saccharomyces cerevisiae , Códon/genética , Mutação , Organismos Geneticamente Modificados , Proteostase/genética , Processamento Pós-Transcricional do RNA/genética , RNA de Transferência/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
10.
Biomolecules ; 10(2)2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32085421

RESUMO

Modifications found in the Anticodon Stem Loop (ASL) of tRNAs play important roles in regulating translational speed and accuracy. Threonylcarbamoyl adenosine (t6A37) and 5-methoxycarbonyl methyl-2-thiouridine (mcm5s2U34) are critical ASL modifications that have been linked to several human diseases. The model yeast Saccharomyces cerevisiae is viable despite the absence of both modifications, growth is however greatly impaired. The major observed consequence is a subsequent increase in protein aggregates and aberrant morphology. Proteomic analysis of the t6A-deficient strain (sua5 mutant) revealed a global mistranslation leading to protein aggregation without regard to physicochemical properties or t6A-dependent or biased codon usage in parent genes. However, loss of sua5 led to increased expression of soluble proteins for mitochondrial function, protein quality processing/trafficking, oxidative stress response, and energy homeostasis. These results point to a global function for t6A in protein homeostasis very similar to mcm5/s2U modifications.


Assuntos
Proteínas de Ligação a DNA/genética , Histona Acetiltransferases/genética , RNA de Transferência/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Anticódon/genética , Anticódon/metabolismo , Proteínas de Ligação a DNA/metabolismo , Histona Acetiltransferases/metabolismo , Conformação de Ácido Nucleico , Fenótipo , Agregados Proteicos/fisiologia , Biossíntese de Proteínas/genética , Biossíntese de Proteínas/fisiologia , Proteínas/genética , Proteômica/métodos , RNA de Transferência/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Termodinâmica , Tiouridina/análogos & derivados , Tiouridina/química
11.
Crit Care Explor ; 1(8): e0024, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32166266

RESUMO

Determining whether a patient has taken a direct oral anticoagulant (DOAC) is critical during the periprocedural and preoperative period in the emergency department. However, the inaccessibility of complete medical records, along with the generally inconsistent sensitivity of conventional coagulation tests to these drugs, complicates clinical decision making and puts patients at risk of uncontrollable bleeding. In this study, we evaluate the utility of inhibitor-II-X (i-II-X), a novel, microfluidics-based diagnostic assay for the detection and identification of Factor Xa inhibitors (FXa-Is) in an acute care setting. DESIGN: First-in-human, 91-patient, single-center retrospective pilot study. SETTING: Emergency room. PATIENTS: Adult patients admitted into the emergency department, which received any clinician-ordered coagulation test requiring a 3.2% buffered sodium citrate blood collection tube. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Plasma samples from patients admitted to the emergency department were screened for the use of FXa-Is, including apixaban and rivaroxaban, within the past 24 hours using our new i-II-X microfluidic test. i-II-X results were then compared with results from conventional coagulation tests, including prothrombin time (PT) and international normalized ratio (INR), which were ordered by treating clinicians, and an anti-Xa assay for rivaroxaban. The i-II-X test detected DOACs in samples collected from the emergency department with 95.20% sensitivity and 100.00% specificity. Unlike PT and INR, i-II-X reliably identified patients who had prolonged clotting times secondary to the presence of a FXa-I. CONCLUSIONS: The i-II-X test overcomes the limitations of currently available coagulation tests and could be a useful tool by which to routinely screen patients for DOACs in emergency and critical care settings. Our new diagnostic approach is particularly relevant in clinical situations where medical records may be unavailable, or where precautions need to be taken prior to invasive interventions, such as specific reversal agent administration.

12.
Cogn Behav Neurol ; 31(3): 151-155, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30239465

RESUMO

Auditory agnosia is an inability to make sense of sound that cannot be explained by deficits in low-level hearing. In view of recent promising results in the area of neurorehabilitation of language disorders after stroke, we examined the effect of transcranial direct current stimulation (tDCS) in a young woman with general auditory agnosia caused by traumatic injury to the left inferior colliculus. Specifically, we studied activations to sound embedded in a block design using functional magnetic resonance imaging before and after application of anodal tDCS to the right auditory cortex. Before tDCS, auditory discrimination deficits were associated with abnormally reduced activations of the auditory cortex and bilateral unresponsiveness of the anterior superior temporal sulci and gyri. This session replicated a previous functional scan with the same paradigm a year before the current experiment. We then applied anodal tDCS over right auditory cortex for 20 min-utes and immediately re-scanned the patient. We found increased activation of bilateral auditory cortices and, for speech sounds, selectively increased activation in Broca's and Wernicke's areas. Future research might consider the long-term behavioral effects after neurostimulation in auditory agnosia and its potential use in the neurorehabilitation of more general auditory disorders.


Assuntos
Agnosia/fisiopatologia , Córtex Auditivo , Lesões Encefálicas Traumáticas , Colículos Inferiores/lesões , Fala , Adulto , Feminino , Humanos , Estimulação Transcraniana por Corrente Contínua
13.
J Genet ; 97(2): 549-553, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29932075

RESUMO

High-throughput sequencing tools promise to revolutionize many aspects of genetic research, e.g. by allowing the identification of functional adaptive genetic variation. However, the expense and expertise required to apply these tools to basic conservation questions is a challenge for applications outside academia, resulting in a so-called 'conservation genomics gap' (Shafer et al. 2015). The conservation genetics paradigm is that, basic information about inbreeding and gene flow are often critical to inform conservation management of small populations (Ouborg et al. 2010). This information is often needed quickly and ideally should be accessible to workers without special expertise in genomics (DeSalle and Amato 2004). While the inferential power of highthroughput sequencing to interrogate the genome is profound, the cost for population analysis is higher (though decreasing) than for traditional neutral markers. Thus, the use of neutral markers is still relevant in conservation applications. However, this assumes that neutral markers have been discovered and characterized for a given species of conservation concern, which is often untrue for nonmodel organisms. Here, we use a fast, cost-efficient, high-throughput sequencing method (Illumina MiSeq) to rapidly identify and characterize microsatellites in the mountain bongo (Tragelaphus eurycerus isaaci), which has a clear and timely conservation imperative but lacks any described neutral markers.


Assuntos
Antílopes/genética , Espécies em Perigo de Extinção , Repetições de Microssatélites/genética , Polimorfismo Genético , Animais , Conservação dos Recursos Naturais/métodos , Fluxo Gênico , Frequência do Gene , Genética Populacional , Genômica , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala/veterinária
14.
15.
PeerJ ; 5: e3846, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29018601

RESUMO

The autonomous sensory meridian response (ASMR) is an atypical sensory phenomenon involving electrostatic-like tingling sensations in response to certain sensory, primarily audio-visual, stimuli. The current study used an online questionnaire, completed by 130 people who self-reported experiencing ASMR. We aimed to extend preliminary investigations into the experience, and establish key multisensory factors contributing to the successful induction of ASMR through online media. Aspects such as timing and trigger load, atmosphere, and characteristics of ASMR content, ideal spatial distance from various types of stimuli, visual characteristics, context and use of ASMR triggers, and audio preferences are explored. Lower-pitched, complex sounds were found to be especially effective triggers, as were slow-paced, detail-focused videos. Conversely, background music inhibited the sensation for many respondents. These results will help in designing media for ASMR induction.

16.
Front Hum Neurosci ; 11: 63, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28261075

RESUMO

Advances in neuroscience and pharmacology have led to improvements in the cognitive performance of people with neurological disease and other forms of cognitive decline. These same methods may also afford cognitive enhancement in people of otherwise normal cognitive abilities. "Cosmetic", or supranormal, cognitive enhancement offers opportunities to enrich our social or financial status, our interactions with others, and the common wealth of our community. It is common to focus on the potential benefits of cognitive enhancement, while being less than clear about the possible drawbacks. Here I examine the harms or side-effects associated with a range of cognitive enhancement interventions. I propose a taxonomy of harms in cognitive enhancement, with harms classified as (neuro)biological, ethical, or societal. Biological harms are those that directly affect the person's biological functioning, such as when a drug affects a person's mood or autonomic function. Ethical harms are those that touch on issues such as fairness and cheating, or on erosion of autonomy and coercion. Societal harms are harms that affect whole populations, and which are normally the province of governments, such as the use of enhancement in military contexts. This taxonomy of harms will help to focus the debate around the use and regulation of cognitive enhancement. In particular it will help to clarify the appropriate network of stakeholders who should take an interest in each potential harm, and in minimizing the impact of these harms.

17.
Front Psychol ; 7: 315, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26973591

RESUMO

Negative emotional responses to the daily life stresses have cumulative effects which, in turn, impose wide-ranging negative constraints on emotional well being and neurocognitive performance (Kalueff and Nutt, 2007; Nadler et al., 2010; Charles et al., 2013). Crucial cognitive functions such as memory and problem solving, as well more short term emotional responses (e.g., anticipation of- and response to- monetary rewards or losses) are influenced by mood. The negative impact of these behavioral responses is felt at the individual level, but it also imposes major economic burden on modern healthcare systems. Although much research has been undertaken to understand the underlying mechanisms of depressed mood and design efficient treatment pathways, comparatively little was done to characterize mood modulations that remain within the boundaries of a healthy mental functioning. In one placebo-controlled experiment, we applied daily prefrontal transcranial Direct Current Stimulation (tDCS) at five points in time, and found reliable improvements on self-reported mood evaluation. Using a new team of experimenters, we replicated this finding in an independent double-blinded placebo-controlled experiment and showed that stimulation over a shorter period of time (3 days) is sufficient to create detectable mood improvements. Taken together, our data show that repeated bilateral prefrontal tDCS can reduce psychological distress in non-depressed individuals.

18.
PeerJ ; 3: e851, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25834771

RESUMO

Autonomous Sensory Meridian Response (ASMR) is a previously unstudied sensory phenomenon, in which individuals experience a tingling, static-like sensation across the scalp, back of the neck and at times further areas in response to specific triggering audio and visual stimuli. This sensation is widely reported to be accompanied by feelings of relaxation and well-being. The current study identifies several common triggers used to achieve ASMR, including whispering, personal attention, crisp sounds and slow movements. Data obtained also illustrates temporary improvements in symptoms of depression and chronic pain in those who engage in ASMR. A high prevalence of synaesthesia (5.9%) within the sample suggests a possible link between ASMR and synaesthesia, similar to that of misophonia. Links between number of effective triggers and heightened flow state suggest that flow may be necessary to achieve sensations associated with ASMR.

19.
Helicobacter ; 20(4): 239-51, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25728540

RESUMO

Idiopathic thrombocytopenic purpura (ITP) is typically a diagnosis of exclusion, assigned by clinicians after ruling out other identifiable etiologies. Since a report by Gasbarrini et al. in 1998, an accumulating body of evidence has proposed a pathophysiological link between ITP and chronic Helicobacter pylori (H. pylori) infection. Clinical reports have described a spontaneous resolution of ITP symptoms in about 50% of chronic ITP patients following empirical treatment of H. pylori infection, but response appears to be geography dependent. Studies have also documented that ITP patients in East Asian countries are more likely to express positive antibody titers against H. pylori-specific cytotoxic-associated gene A (CagA), a virulence factor that is associated with an increased risk for gastric diseases including carcinoma. While a definitive mechanism by which H. pylori may induce thrombocytopenia remains elusive, proposed pathways include molecular mimicry of CagA by host autoantibodies against platelet surface glycoproteins, as well as perturbations in the phagocytic activity of monocytes. Traditional treatments of ITP have been largely empirical, involving the use of immunosuppressive agents and immunoglobulin therapy. However, based on the findings of clinical reports emerging over the past 20 years, health organizations around the world increasingly suggest the detection and eradication of H. pylori as a treatment for ITP. Elucidating the exact molecular mechanisms of platelet activation in H. pylori-positive ITP patients, while considering biogeographical differences in response rates, could offer insight into how best to use clinical H. pylori eradication to treat ITP, but will require well-designed studies to confirm the suggested causative relationship between bacterial infection and an autoimmune disease state.


Assuntos
Antibacterianos/uso terapêutico , Doenças Autoimunes/imunologia , Infecções por Helicobacter/imunologia , Helicobacter pylori/imunologia , Púrpura Trombocitopênica Idiopática , Adulto , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Doenças Autoimunes/genética , Doenças Autoimunes/microbiologia , Autoimunidade/genética , Autoimunidade/imunologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Plaquetas/imunologia , Biologia Computacional , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Humanos , Imunização Passiva , Imunossupressores/uso terapêutico , Pessoa de Meia-Idade , Mimetismo Molecular/genética , Mimetismo Molecular/imunologia , Filogeografia , Ativação Plaquetária/imunologia , Glicoproteínas da Membrana de Plaquetas/imunologia , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Púrpura Trombocitopênica Idiopática/imunologia , Púrpura Trombocitopênica Idiopática/microbiologia
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