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1.
Artigo em Inglês | MEDLINE | ID: mdl-39287622

RESUMO

AlN is deposited on silicon carbide (SiC) for high-power electronics; in these devices, AlN acts as both a buffer layer for the growth of the active device and a thermal conductor. However, the mechanism of thermal transport through the AlN-SiC interfaces and through grain boundaries of AlN has not been clearly analyzed, even though AlN forms grain boundaries during the deposition process. The thermal properties of the AlN-SiC interface and the inversion domain boundaries (IDBs) of AlN were examined by a phonon transport model based on a nonequilibrium Green function formalism and first-principles calculations. The interface and grain boundary models were designed, and the thermal resistances (TRs) and origins of TR were examined. The TRs of the AlN-SiC interface and the IDB of AlN are much higher than the TRs of AlN and SiC of relevant thickness. Elemental intermixing and vacancy formation were modeled. The formation of charge-balanced defect of VAl + 3ON is thermodynamically favorable compared to other defects, indicating that ON induces formation of VAl. The charge-balanced defect combining VAl and ON increases the TRs of both AlN-SiC interfaces and AlN grain boundaries because vacancy defects induce larger changes in mass than all other defects, and TRs are proportional to changes in mass. In addition, VAl defects are increased by excess ON, resulting in a continuous increase in TR, and then, the calculated thermal boundary resistance (TBR) of the AlN-SiC interface with increased density of VAl by excess ON reaches the experimental TBR. Therefore, it is expected that the large increase in TR by the formation of VAl + ON would be suppressed by controlling the low O density during synthesis.

2.
J Med Life ; 17(3): 318-325, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39044922

RESUMO

This secondary analysis of the CAPTAIN-RTMS trial data focused on the significance of quantitative electroencephalography (qEEG) indices as indicators of recovery in patients with traumatic brain injury (TBI). By focusing on the delta alpha ratio (DAR), delta theta/alpha beta ratio (DTABR), and theta beta ratio (TBR), this study explored the shifts in brainwave activity as a response to an integrative treatment regimen of repetitive transcranial magnetic stimulation (rTMS) combined with the neurotrophic agent Cerebrolysin. Findings revealed significant increases in DAR and DTABR, suggesting changes in neurophysiological dynamics after treatment. However, variations in TBR were inconclusive in providing clear electrophysiological insights. These results indicate that further research is necessary to describe and understand the underlying mechanisms of brain recovery and to develop refined treatment frameworks for patients with TBI.


Assuntos
Lesões Encefálicas Traumáticas , Eletroencefalografia , Estimulação Magnética Transcraniana , Lesões Encefálicas Traumáticas/terapia , Lesões Encefálicas Traumáticas/fisiopatologia , Humanos , Eletroencefalografia/métodos , Estimulação Magnética Transcraniana/métodos , Masculino , Adulto , Feminino , Pessoa de Meia-Idade , Aminoácidos
3.
Interact J Med Res ; 13: e50849, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39083801

RESUMO

BACKGROUND: The impact of missing data on individual continuous glucose monitoring (CGM) data is unknown but can influence clinical decision-making for patients. OBJECTIVE: We aimed to investigate the consequences of data loss on glucose metrics in individual patient recordings from continuous glucose monitors and assess its implications on clinical decision-making. METHODS: The CGM data were collected from patients with type 1 and 2 diabetes using the FreeStyle Libre sensor (Abbott Diabetes Care). We selected 7-28 days of 24 hours of continuous data without any missing values from each individual patient. To mimic real-world data loss, missing data ranging from 5% to 50% were introduced into the data set. From this modified data set, clinical metrics including time below range (TBR), TBR level 2 (TBR2), and other common glucose metrics were calculated in the data sets with and that without data loss. Recordings in which glucose metrics deviated relevantly due to data loss, as determined by clinical experts, were defined as expert panel boundary error (εEPB). These errors were expressed as a percentage of the total number of recordings. The errors for the recordings with glucose management indicator <53 mmol/mol were investigated. RESULTS: A total of 84 patients contributed to 798 recordings over 28 days. With 5%-50% data loss for 7-28 days recordings, the εEPB varied from 0 out of 798 (0.0%) to 147 out of 736 (20.0%) for TBR and 0 out of 612 (0.0%) to 22 out of 408 (5.4%) recordings for TBR2. In the case of 14-day recordings, TBR and TBR2 episodes completely disappeared due to 30% data loss in 2 out of 786 (0.3%) and 32 out of 522 (6.1%) of the cases, respectively. However, the initial values of the disappeared TBR and TBR2 were relatively small (<0.1%). In the recordings with glucose management indicator <53 mmol/mol the εEPB was 9.6% for 14 days with 30% data loss. CONCLUSIONS: With a maximum of 30% data loss in 14-day CGM recordings, there is minimal impact of missing data on the clinical interpretation of various glucose metrics. TRIAL REGISTRATION: ClinicalTrials.gov NCT05584293; https://clinicaltrials.gov/study/NCT05584293.

4.
Development ; 151(14)2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38912572

RESUMO

The neurons of the three cerebellar nuclei (CN) are the primary output neurons of the cerebellum. The excitatory neurons (e) of the medial (m) CN (eCNm) were recently divided into molecularly defined subdomains in the adult; however, how they are established during development is not known. We define molecular subdomains of the mouse embryonic eCNm using single-cell RNA-sequencing and spatial expression analysis, showing that they evolve during embryogenesis to prefigure the adult. Furthermore, eCNm are transcriptionally divergent from cells in the other nuclei by embryonic day 14.5. We previously showed that loss of the homeobox genes En1 and En2 leads to loss of approximately half of the embryonic eCNm. We demonstrate that mutation of En1/2 in the embryonic eCNm results in death of specific posterior eCNm molecular subdomains and downregulation of TBR2 (EOMES) in an anterior embryonic subdomain, as well as reduced synaptic gene expression. We further reveal a similar function for EN1/2 in mediating TBR2 expression, neuron differentiation and survival in the other excitatory neurons (granule and unipolar brush cells). Thus, our work defines embryonic eCNm molecular diversity and reveals conserved roles for EN1/2 in the cerebellar excitatory neuron lineage.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio , Neurônios , Animais , Proteínas de Homeodomínio/metabolismo , Proteínas de Homeodomínio/genética , Camundongos , Neurônios/metabolismo , Neurônios/citologia , Sobrevivência Celular/genética , Diferenciação Celular/genética , Cerebelo/embriologia , Cerebelo/metabolismo , Cerebelo/citologia , Proteínas com Domínio T/metabolismo , Proteínas com Domínio T/genética , Núcleos Cerebelares/metabolismo , Núcleos Cerebelares/embriologia , Núcleos Cerebelares/citologia , Análise de Célula Única , Proteínas do Tecido Nervoso
5.
Artigo em Inglês | MEDLINE | ID: mdl-38858282

RESUMO

The frequently reported high theta/beta ratio (TBR) in the electroencephalograms (EEGs) of children with attention-deficit/hyperactivity disorder (ADHD) has been suggested to include at least two distinct neurophysiological subgroups, a subgroup with high TBR and one with slow alpha peak frequency, overlapping the theta range. We combined three large ADHD cohorts recorded under standardized procedures and used a meta-analytical approach to leverage the large sample size (N = 417; age range: 6-18 years), classify these EEG subtypes and investigate their behavioral correlates to clarify their brain-behavior relationships. To control for the fact that slow alpha might contribute to theta power, three distinct EEG subgroups (non-slow-alpha TBR (NSAT) subgroup, slow alpha peak frequency (SAF) subgroup, not applicable (NA) subgroup) were determined, based on a halfway cut-off in age- and sex-normalized theta and alpha, informed by previous literature. For the meta-analysis, Cohen's d was calculated to assess the differences between EEG subgroups for baseline effects, using means and standard deviations of baseline inattention and hyperactivity-impulsivity scores. Non-significant, small Grand Mean effect sizes (-0.212 < d < 0.218) were obtained when comparing baseline behavioral scores between the EEG subgroups. This study could not confirm any association of EEG subtype with behavioral traits. This confirms previous findings suggesting that TBR has no diagnostic value for ADHD. TBR could, however, serve as an aid to stratify patients between neurofeedback protocols based on baseline TBR. A free online tool was made available for clinicians to calculate age- and sex-corrected TBR decile scores (Brainmarker-IV) for stratification of neurofeedback protocols.

6.
Dev Cell ; 59(15): 1913-1923.e6, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38772376

RESUMO

Neural stem cells (NSCs) differentiate into neuron-fated intermediate progenitor cells (IPCs) via cell division. Although differentiation from NSCs to IPCs is a discrete process, recent transcriptome analyses identified a continuous transcriptional trajectory during this process, raising the question of how to reconcile these contradictory observations. In mouse NSCs, Hes1 expression oscillates, regulating the oscillatory expression of the proneural gene Neurog2, while Hes1 expression disappears in IPCs. Thus, the transition from Hes1 oscillation to suppression is involved in the differentiation of NSCs to IPCs. Here, we found that Neurog2 oscillations induce the accumulation of Tbr2, which suppresses Hes1 expression, generating an IPC-like gene expression state in NSCs. In the absence of Tbr2, Hes1 expression is up-regulated, decreasing the formation of IPCs. These results indicate that the Neurog2-Tbr2 axis forms a continuous transcriptional trajectory to an IPC-like neurogenic state in NSCs, which then differentiate into IPCs via cell division.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos , Diferenciação Celular , Proteínas do Tecido Nervoso , Células-Tronco Neurais , Neurogênese , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/citologia , Animais , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/genética , Camundongos , Neurogênese/genética , Regulação da Expressão Gênica no Desenvolvimento , Fatores de Transcrição HES-1/metabolismo , Fatores de Transcrição HES-1/genética , Neurônios/metabolismo , Neurônios/citologia , Proteínas com Domínio T
7.
Neuron ; 112(13): 2157-2176.e12, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38697111

RESUMO

Mutations in human nonsense-mediated mRNA decay (NMD) factors are enriched in neurodevelopmental disorders. We show that deletion of key NMD factor Upf2 in mouse embryonic neural progenitor cells causes perinatal microcephaly but deletion in immature neurons does not, indicating NMD's critical roles in progenitors. Upf2 knockout (KO) prolongs the cell cycle of radial glia progenitor cells, promotes their transition into intermediate progenitors, and leads to reduced upper-layer neurons. CRISPRi screening identified Trp53 knockdown rescuing Upf2KO progenitors without globally reversing NMD inhibition, implying marginal contributions of most NMD targets to the cell cycle defect. Integrated functional genomics shows that NMD degrades selective TRP53 downstream targets, including Cdkn1a, which, without NMD suppression, slow the cell cycle. Trp53KO restores the progenitor cell pool and rescues the microcephaly of Upf2KO mice. Therefore, one physiological role of NMD in the developing brain is to degrade selective TRP53 targets to control progenitor cell cycle and brain size.


Assuntos
Encéfalo , Camundongos Knockout , Células-Tronco Neurais , Degradação do RNAm Mediada por Códon sem Sentido , Proteína Supressora de Tumor p53 , Animais , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Camundongos , Encéfalo/metabolismo , Células-Tronco Neurais/metabolismo , Degradação do RNAm Mediada por Códon sem Sentido/genética , Epistasia Genética , Microcefalia/genética , Ciclo Celular/fisiologia , Ciclo Celular/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética
8.
BMC Psychol ; 12(1): 245, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689352

RESUMO

Decision-making under uncertainty, a cornerstone of human cognition, is encapsulated by the "secretary problem" in optimal stopping theory. Our study examines this decision-making challenge, where participants are required to sequentially evaluate and make irreversible choices under conditions that simulate cognitive overload. We probed neurophysiological responses by engaging 27 students in a secretary problem simulation while undergoing EEG monitoring, focusing on Event-Related Potentials (ERPs) P200 and P400, and Theta to Beta Ratio (TBR) dynamics.Results revealed a nuanced pattern: the P200 component's amplitude declined from the initial to the middle offers, suggesting a diminishing attention span as participants grew accustomed to the task. This attenuation reversed at the final offer, indicating a heightened cognitive processing as the task concluded. In contrast, the P400 component's amplitude peaked at the middle offer, hinting at increased cognitive evaluation, and tapered off at the final decision. Additionally, TBR dynamics illustrated a fluctuation in attentional control and emotional regulation throughout the decision-making sequence, enhancing our understanding of the cognitive strategies employed.The research elucidates the dynamic interplay of cognitive processes in high-stakes environments, with neurophysiological markers fluctuating significantly as participants navigated sequential choices. By correlating these fluctuations with decision-making behavior, we provide insights into the evolving strategies from heightened alertness to strategic evaluation. Our findings offer insights that could inform the use of neurophysiological data in the development of decision-making frameworks, potentially contributing to the practical application of cognitive research in real-life contexts.


Assuntos
Atenção , Tomada de Decisões , Eletroencefalografia , Potenciais Evocados , Humanos , Tomada de Decisões/fisiologia , Potenciais Evocados/fisiologia , Masculino , Feminino , Adulto Jovem , Atenção/fisiologia , Adulto , Cognição/fisiologia , Encéfalo/fisiologia , Incerteza , Ritmo Teta/fisiologia , Ritmo beta/fisiologia
9.
FASEB J ; 38(6): e23568, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38522021

RESUMO

The development of musculoskeletal tissues such as tendon, enthesis, and bone relies on proliferation and differentiation of mesenchymal progenitor cells. Gli1+ cells have been described as putative stem cells in several tissues and are presumed to play critical roles in tissue formation and maintenance. For example, the enthesis, a fibrocartilage tissue that connects tendon to bone, is mineralized postnatally by a pool of Gli1+ progenitor cells. These cells are regulated by hedgehog signaling, but it is unclear if TGFß signaling, necessary for tenogenesis, also plays a role in their behavior. To examine the role of TGFß signaling in Gli1+ cell function, the receptor for TGFß, TbR2, was deleted in Gli1-lineage cells in mice at P5. Decreased TGFß signaling in these cells led to defects in tendon enthesis formation by P56, including defective bone morphometry underlying the enthesis and decreased mechanical properties. Immunohistochemical staining of these Gli1+ cells showed that loss of TGFß signaling reduced proliferation and increased apoptosis. In vitro experiments using Gli1+ cells isolated from mouse tail tendons demonstrated that TGFß controls cell proliferation and differentiation through canonical and non-canonical pathways and that TGFß directly controls the tendon transcription factor scleraxis by binding to its distant enhancer. These results have implications in the development of treatments for tendon and enthesis pathologies.


Assuntos
Proteínas Hedgehog , Fator de Crescimento Transformador beta , Animais , Camundongos , Proteínas Hedgehog/genética , Proteína GLI1 em Dedos de Zinco/genética , Tendões , Transdução de Sinais
10.
Reprod Biomed Online ; 48(2): 103619, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38147814

RESUMO

RESEARCH QUESTION: Do embryos that undergo a thaw, biopsy and re-vitrification (TBR) for pre-implantation genetic testing for aneuploidy (PGT-A) have different ploidy and transfer outcomes compared with fresh biopsied embryos? DESIGN: Retrospective cohort study of all embryos that underwent the following procedures: fresh biopsy for PGT-A (fresh biopsy); embryos that were warmed, biopsied for PGT-A and re-vitrified (single biopsy TBR); embryos with a no signal result after initial biopsy that were subsequently warmed, biopsied and re-vitrified (double biopsy TBR). The patients who underwent transfers of those embryos at a single academic institution between March 2013 and December 2021 were also studied. RESULTS: About 30% of embryos planned for TBR underwent attrition. Euploidy rates were similar after biopsy: fresh biopsy (42.7%); single biopsy TBR (47.5%) (adjusted RR: 0.99, 0.88 to 1.12); and double biopsy TBR 50.3% (adjusted RR: 0.99, 0.80 to 1.21). Ongoing pregnancy over 8 weeks was not statistically significant (double biopsy TBR: 6/19 [31.6%] versus fresh biopsy: 650/1062 [61.2%]) (adjusted RR 0.52, 95% CI 0.26 to 1.03). The miscarriage rate increased (double biopsy TBR: 4/19 [21.1%] versus fresh biopsy: 66/1062 [6.2%])(RR 3.39, 95% CI 1.38 to 8.31). Live birth rate was also lower per transfer for the double biopsy TBR group (double biopsy TBR [18.75%] versus fresh biopsy [53.75%]) (RR 0.35, 95% CI 0.12 to 0.98), though not after adjustment (adjusted RR 0.37, 95% CI 0.13 to 1.09). These differences were not seen when single biopsy TBR embryos were transferred. CONCLUSIONS: Embryos that undergo TBR have an equivalent euploidy rate to fresh biopsied embryos. Despite that, double biopsy TBR embryos may have impaired transfer outcomes.


Assuntos
Criopreservação , Diagnóstico Pré-Implantação , Gravidez , Feminino , Humanos , Estudos Retrospectivos , Blastocisto/patologia , Implantação do Embrião , Taxa de Gravidez
11.
Int J Mol Sci ; 24(19)2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37834410

RESUMO

Lipopolysaccharide (LPS) is a natural agonist of toll-like receptor 4 that serves a role in innate immunity. The current study evaluated the LPS-mediated regulation of neurogenesis in the subventricular zone (SVZ) progenitors, that is, the basal radial glia and intermediate progenitors (IPs), in ferrets. Ferret pups were subcutaneously injected with LPS (500 µg/g of body weight) on postnatal days (PDs) 6 and 7. Furthermore, 5-ethynyl-2'-deoxyuridine (EdU) and 5-bromo-2'-deoxyuridine (BrdU) were administered on PDs 5 and 7, respectively, to label the post-proliferative and proliferating cells in the inner SVZ (iSVZ) and outer SVZ (oSVZ). A significantly higher density of BrdU single-labeled proliferating cells was observed in the iSVZ of LPS-exposed ferrets than in controls but not in post-proliferative EdU single-labeled and EdU/BrdU double-labeled self-renewing cells. BrdU single-labeled cells exhibited a lower proportion of Tbr2 immunostaining in LPS-exposed ferrets (22.2%) than in controls (42.6%) and a higher proportion of Ctip2 immunostaining in LPS-exposed ferrets (22.2%) than in controls (8.6%). The present findings revealed that LPS modified the neurogenesis of SVZ progenitors. Neonatal LPS exposure facilitates the proliferation of SVZ progenitors, followed by the differentiation of Tbr2-expressing IPs into Ctip2-expressing immature neurons.


Assuntos
Neocórtex , Animais , Ventrículos Laterais , Furões , Lipopolissacarídeos , Bromodesoxiuridina , Neurogênese/fisiologia , Proliferação de Células
12.
Psychiatry Res Neuroimaging ; 335: 111723, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37862958

RESUMO

Attention Deficit/Hyperactivity Disorder (ADHD) is a common neurodevelopmental disorder of childhood and its effects mostly continue to adulthood. Neurofeedback training has shown promising results in the treatment of ADHD. However, there is no yet consensus as to the efficacy of neurofeedback in comparison to stimulant medication. Despite a large number of meta-analyses and comparative reviews on the effects of neurofeedback in the treatment of ADHD, there is a lack of comparative reviews on the efficacy of neurofeedback protocols. This review aims at examining the effect of different training protocols on the efficacy of neurofeedback in the treatment of ADHD across specific research studies published between 2017 and 2022. Altogether, a total of 916 records were identified and 18 articles met the inclusion criteria. Findings show that the efficacy of different neurofeedback protocols has been comparable to the efficacy of stimulant medications. Nevertheless, there is still room for more clinical trials on neurofeedback protocols for ADHD since some studies suggest not using neurofeedback as a stand-alone treatment for ADHD. To my knowledge, this systematic review is the first to review neurofeedback protocols for ADHD. This study provides significant implications and directions for researchers to conduct research, on alternatives to stimulant medications for ADHD, in the future.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Protocolos Clínicos , Neurorretroalimentação , Humanos , Transtorno do Deficit de Atenção com Hiperatividade/terapia , Neurorretroalimentação/métodos , Resultado do Tratamento
13.
Trop Anim Health Prod ; 55(4): 279, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37505344

RESUMO

Trypanosoma brucei evansi (T. b. evansi) is an enzootic organism found in Egyptian camels, which genetically classified into types A and B. To detect the parasite genotype circulating in Egyptian camels, we collected 94 blood samples from three distant districts and subjected them to different PCR assays; T. brucei repeat (TBR), internal transcribed spacer-1 (ITS-1), and variable surface glycoproteins (VSG) (RoTat 1. 2, JN 2118Hu) and EVAB PCRs. The highest prevalence was obtained with TBR (80/91; 87.9%), followed by ITS-1 (52/91; 57.1%), VSG JN 2118Hu (42/91; 46.2%), and VSG RoTat 1. 2 (34/91; 37.4%). We reported a different non-RoTat 1. 2 T. b. evansi for the first time in Egyptian camels. Results showed that 47 (58.7%) out of 80 samples were classified as T. b. evansi. Of these, 14 (29.8%) were RoTat 1. 2 type, 13 (27.6%) were non-RoTat 1. 2 type, and 20 (42.6%) samples were from mixed infection with both types. All samples were tested negative with EVAB PCR. RoTat 1. 2 T. b. evansi was the most prevalent in Giza and El Nubariyah, whereas, in Aswan, the only type detected was non-RoTat 1. 2 T. b. evansi. The nucleotide sequences of the VSG RoTat 1.2 and JN 2118Hu PCR products were submitted to DNA Data Bank of Japan (DDBJ) and GenBank under the accession numbers LC738852, and (OP800400-OP800403). Further research is required to increase the sample size and verify the new sequences to corroborate the prevalence of a new variant of non-RoTat 1.2 T. b. evansi in Egypt.


Assuntos
Trypanosoma brucei brucei , Trypanosoma , Tripanossomíase , Animais , Tripanossomíase/epidemiologia , Tripanossomíase/veterinária , Camelus/parasitologia , Egito/epidemiologia , Genótipo , Trypanosoma/genética
14.
Proc Natl Acad Sci U S A ; 120(28): e2220918120, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37406098

RESUMO

Understanding the claustrum's functions has recently progressed thanks to new anatomical and behavioral studies in rodents, which suggest that it plays an important role in attention, salience detection, slow-wave generation, and neocortical network synchronization. Nevertheless, knowledge about the origin and development of the claustrum, especially in primates, is still limited. Here, we show that neurons of rhesus macaque claustrum primordium are generated between embryonic day E48 and E55 and express some neocortical molecular markers, such as NR4A2, SATB2, and SOX5. However, in the early stages, it lacks TBR1 expression, which separates it from other surrounding telencephalic structures. We also found that two waves of neurogenesis (E48 and E55) in the claustrum, corresponding to the birthdates of layers 6 and 5 of the insular cortex, establish a "core" and "shell" cytoarchitecture, which is potentially a basis for differential circuit formation and could influence information processing underlying higher cognitive functions of the claustrum. In addition, parvalbumin-positive interneurons are the dominant interneuron type in the claustrum in fetal macaque, and their maturation is independent of that in the overlaying neocortex. Finally, our study reveals that the claustrum is likely not a continuance of subplate neurons of the insular cortex, but an independent pallial region, suggesting its potentially unique role in cognitive control.


Assuntos
Claustrum , Neocórtex , Animais , Macaca mulatta , Neurônios/metabolismo , Interneurônios
15.
Cogn Emot ; 37(6): 1116-1122, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37287280

RESUMO

Previous research has shown that the proactive deprioritization of emotional distractors through the provision of information about the distractors or passive habituation of emotional distractors may attenuate emotion-induced blindness (EIB) in the rapid serial visual presentation stream. However, whether prior memory encoding of emotional distractors could bias the EIB effect remains unknown. To address this question, this study employed a three-phase paradigm integrating an item-method direct forgetting (DF) procedure with a classic EIB procedure. Participants completed a memory coding phase to either remember or forget negative pictures, then performed an intermediate phase of the EIB test, and finally finished a recognition test. Critically, the same to-be-forgotten (TBF) and to-be-remembered (TBR) negative pictures in the memory learning phase were used as emotional distractors in the intermediate EIB test. The results replicated the typical DF effect by showing higher recognition accuracies for TBR pictures compared to those for TBF pictures. More importantly, the TBF negative distractors attenuated the EIB effect compared to the TBR negative distractors, but showed a comparable EIB effect as the novel negative distractors. These findings indicate that prior memory encoding manipulations of negative distractors could bias subsequent EIB effects, providing an important approach to modulate the EIB effect.


Assuntos
Eletroencefalografia , Potenciais Evocados , Humanos , Eletroencefalografia/métodos , Emoções , Reconhecimento Psicológico , Rememoração Mental , Viés , Sinais (Psicologia)
16.
Elife ; 122023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37219072

RESUMO

Expressions of voltage-gated sodium channels Nav1.1 and Nav1.2, encoded by SCN1A and SCN2A genes, respectively, have been reported to be mutually exclusive in most brain regions. In juvenile and adult neocortex, Nav1.1 is predominantly expressed in inhibitory neurons while Nav1.2 is in excitatory neurons. Although a distinct subpopulation of layer V (L5) neocortical excitatory neurons were also reported to express Nav1.1, their nature has been uncharacterized. In hippocampus, Nav1.1 has been proposed to be expressed only in inhibitory neurons. By using newly generated transgenic mouse lines expressing Scn1a promoter-driven green fluorescent protein (GFP), here we confirm the mutually exclusive expressions of Nav1.1 and Nav1.2 and the absence of Nav1.1 in hippocampal excitatory neurons. We also show that Nav1.1 is expressed in inhibitory and a subpopulation of excitatory neurons not only in L5 but all layers of neocortex. By using neocortical excitatory projection neuron markers including FEZF2 for L5 pyramidal tract (PT) and TBR1 for layer VI (L6) cortico-thalamic (CT) projection neurons, we further show that most L5 PT neurons and a minor subpopulation of layer II/III (L2/3) cortico-cortical (CC) neurons express Nav1.1 while the majority of L6 CT, L5/6 cortico-striatal (CS), and L2/3 CC neurons express Nav1.2. These observations now contribute to the elucidation of pathological neural circuits for diseases such as epilepsies and neurodevelopmental disorders caused by SCN1A and SCN2A mutations.


Assuntos
Neocórtex , Camundongos , Animais , Camundongos Transgênicos , Neocórtex/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Tratos Piramidais , Canal de Sódio Disparado por Voltagem NAV1.1/genética , Neurônios/fisiologia , Células Piramidais/metabolismo
17.
BMC Neurol ; 23(1): 200, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37210479

RESUMO

BACKGROUND: Continuous glucose monitoring (CGM)-derived time in range (TIR) is closely associated with micro- and macrovascular complications in type 2 diabetes mellitus (T2DM). This study was performed to investigate the relationship between key CGM-derived metrics and specific cognitive domains in patients with T2DM. METHODS: Outpatients with T2DM who were otherwise healthy were recruited for this study. A battery of neuropsychological tests was performed to evaluate cognitive function, including memory, executive functioning, visuospatial ability, attention, and language. Participants wore a blinded flash continuous glucose monitoring (FGM) system for 72 h. The key FGM-derived metrics were calculated, including TIR, time below range (TBR), time above range (TAR), glucose coefficient of variation (CV), and mean amplitude of glycemic excursions (MAGE). Furthermore, the glycemia risk index (GRI) was also calculated by the GRI formula. Binary logistic regression was used to assess risk factors for TBR, and we further analysed the associations between neuropsychological test results and key FGM-derived metrics with multiple linear regressions. RESULTS: A total of 96 outpatients with T2DM were recruited for this study, with 45.8% experiencing hypoglycemia (TBR< 3.9 mmol/L). Spearman analysis results revealed that a higher TBR< 3.9 mmol/L was correlated with worse performance on the Trail Making Test A (TMTA), Clock Drawing Test (CDT), and cued recall scores (P < 0.05). Logistic regression analysis results indicated that the TMTA (OR = 1.010, P = 0.036) and CDT (OR = 0.429, P = 0.016) scores were significant factors influencing the occurrence of TBR< 3.9 mmol/L. Multiple linear regressions further demonstrated that TBR< 3.9 mmol/L (ß = -0.214, P = 0.033), TAR> 13.9 mmol/L (ß = -0.216, P = 0.030) and TAR10.1-13.9 mmol/L (ß = 0.206, P = 0.042) were significantly correlated with cued recall scores after adjusting for confounding factors. However, TIR, GRI, CV and MAGE showed no significant correlation with the results of neuropsychological tests (P > 0.05). CONCLUSIONS: A higher TBR< 3.9 mmol/L and TAR> 13.9 mmol/L were associated with worse cognitive functions (memory, visuospatial ability, and executive functioning). Conversely, a higher TAR of 10.1-13.9 mmol/L was associated with better memory performance in memory tasks.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/complicações , Automonitorização da Glicemia , Glicemia , Pacientes Ambulatoriais , Cognição , Glucose
18.
Dev Cogn Neurosci ; 61: 101248, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37120994

RESUMO

In human and nonhuman primates, the amygdala paralaminar nucleus (PL) contains immature neurons. To explore the PL's potential for cellular growth during development, we compared PL neurons in (1) infant and adolescent macaques (control, maternally-reared), and in (2) infant macaques that experienced separation from their mother in the first month of life compared to control maternally-reared infants. In maternally-reared animals, the adolescent PL had fewer immature neurons, more mature neurons, and larger immature soma volumes compared to infant PL. There were also fewer total neurons (immature plus mature) in adolescent versus infant PL, suggesting that some neurons move out of the PL by adolescence. Maternal separation did not change mean immature or mature neuron counts in infant PL. However, across all infant animals, immature neuron soma volume was strongly correlated with mature neuron counts. TBR1 mRNA, a transcript required for glutamatergic neuron maturation, is significantly reduced in the maternally-separated infant PL (DeCampo et al., 2017), and was also positively correlated with mature neuron counts in infant PL. We conclude that immature neurons gradually mature by adolescence, and that the stress of maternal separation may shift this trajectory, as revealed by correlations between TBR1 mRNA and mature neuron numbers across animals.


Assuntos
Tonsila do Cerebelo , Privação Materna , Humanos , Lactente , Animais , Feminino , Adolescente , Tonsila do Cerebelo/fisiologia , Primatas , Neurônios/fisiologia , Macaca
19.
Endocr J ; 70(7): 677-685, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37019657

RESUMO

Prevention of hypoglycemia is an important strategy for glycemic management in patients with type 1 diabetes mellitus (T1D). Hypoglycemia is difficult to recognize at night while sleeping, particularly when using multiple daily injection (MDI) insulin therapy rather than sensor-augmented insulin-pump therapy. Therefore, it is possible that patients with T1D are at higher risk of nocturnal hypoglycemia when insulin is administered using an MDI regimen. We investigated nocturnal hypoglycemia in 50 pediatric patients with T1D on MDI insulin therapy using data from an intermittently scanned continuous glucose monitoring (isCGM) system. Hypoglycemia was observed on 446 of the 1,270 nights studied. Most of the hypoglycemic episodes were severe (blood glucose <54 mg/dL). On nights when hypoglycemia occurred, the blood glucose concentrations measured using finger-stick blood glucose monitoring (FSGM) before sleep and the next morning were lower than nights when hypoglycemia did not occur. However, few values were below the normal blood glucose range, suggesting that FSGM alone may be insufficient to detect nocturnal hypoglycemia. Approximately 7% of time was spent below the normal glucose range during the 10 hours from 21:00 to 7:00 the next morning. This result suggests that the patients on MDI insulin therapy could end up spending more time in hypoglycemia than is recommended by the American Diabetes Association (time below range <4.0% of time per day). Monitoring glucose levels overnight using an isCGM sensor may improve glycemic management via automatic detection of blood glucose peaks and troughs.


Assuntos
Diabetes Mellitus Tipo 1 , Hipoglicemia , Humanos , Criança , Glicemia , Automonitorização da Glicemia , Hipoglicemiantes/efeitos adversos , População do Leste Asiático , Hipoglicemia/induzido quimicamente , Hipoglicemia/prevenção & controle , Insulina/efeitos adversos , Sistemas de Infusão de Insulina/efeitos adversos
20.
Diabet Med ; 40(6): e15093, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36951684

RESUMO

AIMS: Current continuous glucose monitoring (CGM) devices provide features that alert individuals with diabetes about their current and impending adverse glycaemic events. The use of these features has been associated with glycaemic improvements. However, how these features are utilised under real-world conditions has not been well studied. We queried a large database to quantify utilisation of the Dexcom G6 system features and how utilisation impacted glycaemic outcomes within a cohort of European users. METHODS: This 6-month retrospective, observational, large database analysis utilised anonymised data from a sample of 47,784 Europe-based G6 users. Primary outcome measures were associations between utilisation and customisation of High/Low threshold alerts, 'urgent low soon' (ULS) alert, and established CGM metrics. RESULTS: Users in the Germany, Austria, Switzerland region (n = 20,257), the Nordic countries (n = 10,314), United Kingdom (n = 9006), Italy (n = 4747), France (n = 2130) and Spain (1330) were included. All alert features were utilised by >75% of the cohort across all regions/countries and age groups. Enabling the Low alert and ULS alert was associated with lower percentage of time below range compared to disabling the Low alert (p < 0.001). Enabling the High alert was associated with higher percentage of time in range (%TIR) and lower percentage of time above range (%TAR) %TAR compared to disabling the High alert (p < 0.001). Paediatric patients and older adults tended to set a higher threshold for High/Low alerts, while younger adults tended to use lower threshold values for High/Low alerts. CONCLUSIONS: Individuals who utilised the Dexcom G6 features showed better glycaemic control, particularly among those who utilised more sensitive High alert and Low alert settings, than users who did not utilise the system features.


Assuntos
Glicemia , Diabetes Mellitus Tipo 1 , Humanos , Criança , Idoso , Glicemia/análise , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/epidemiologia , Automonitorização da Glicemia , Estudos Retrospectivos , Europa (Continente)/epidemiologia
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