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1.
J Prim Care Community Health ; 15: 21501319241236009, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38554002

RESUMO

INTRODUCTION/OBJECTIVES: In 2022, 1 in 6 households with children experienced food insecurity (FI) in the United States. The negative impact of FI on child health is well documented and pediatric clinicians are encouraged to actively screen and intervene in clinical settings. This study aims to evaluate the feasibility and impact of a FI management protocol implemented in 2017 at a pediatric primary care health network serving patients who are Medicaid-eligible in Washington, DC. METHODS: In 2019, an 18-item electronic survey was sent to a convenience sample of 42 pediatric clinicians within the health network to understand their knowledge, attitudes, and behaviors surrounding implementation. Both quantitative and qualitative responses were collected and analyzed. We report frequencies of the Likert-type responses, including perceived compliance with protocol components and intervention efficacy. We evaluated the relationship between FI knowledge level and rates of clinician documentation compliance by chi square and Cramer's V statistic for effect size. Open-ended responses were reviewed, and common themes were identified and used to provide context for quantitative results. RESULTS AND CONCLUSIONS: Out of 42 clinicians invited to complete the survey, 35 completed responses. All respondents reported universal screening for FI (100%) at routine examinations, 80% reported frequently electronically documenting FI in medical records, and 91% of clinicians reported frequently referring families who screened positive for FI to at least one FI resource, with 24% reporting that resources met families' needs. Open-ended responses revealed increased awareness of FI prevalence and of patient experiences in households experiencing FI, increased satisfaction with clinical management of FI, but also concerns around having limited clinical time to do the protocol and the usefulness and accessibility of referred resources. In conclusion, implementing this pilot FI protocol was feasible, but clinicians perceived limited impact of the protocol on alleviating FI and desired more robust intervention options. Further improvements include shifting the burden of performing the protocol away from the clinician, such as by streamlining the protocol or identifying a resource staff member, and establishing more accessible and effective FI interventions such as "Food as Medicine" offerings in partnership with community organizations.


Assuntos
Características da Família , Abastecimento de Alimentos , Criança , Humanos , Estados Unidos , Estudos de Viabilidade , Insegurança Alimentar , Atenção Primária à Saúde
2.
JBJS Case Connect ; 13(4)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38048409

RESUMO

CASE: A 16-year-old male adolescent presented with 4 weeks of right-sided hip pain and fever in the setting of recent groin trauma. He was diagnosed with septic arthritis of the pubic symphysis (SAPS) and was treated nonoperatively with antibiotics. Symptoms recurred, and he underwent surgical drainage of the pubic symphysis followed by a prolonged course of antibiotics. Follow-up at 12 months indicated complete symptom resolution. CONCLUSION: This is the ninth reported adolescent case of SAPS. Although the presentation and disease course closely resembled those reported in the literature, this is the only case that required surgical intervention after failed nonoperative management.


Assuntos
Artrite Infecciosa , Sínfise Pubiana , Masculino , Humanos , Adolescente , Sínfise Pubiana/diagnóstico por imagem , Antibacterianos/uso terapêutico , Dor/tratamento farmacológico , Artrite Infecciosa/tratamento farmacológico , Artrite Infecciosa/cirurgia
3.
Pediatr Res ; 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38049646

RESUMO

BACKGROUND: To describe pediatric Produce Prescription (PRx) interventions and their study designs, outcomes, and opportunities for future research. METHODS: A scoping review framework was used to describe PRx interventions published between January 2000 and September 2023. Articles from online databases were uploaded into Covidence. Data on study characteristics, outcomes of interest (health, food insecurity (FI), nutritional and culinary efficacy, and fruit and vegetable (F/V) consumption), and feasibility were extracted. The Mixed Methods Appraisal Tool (MMAT) was used for quality assessment. RESULTS: 19 articles met inclusion criteria. Ten studies were quantitative, five were qualitative, and four used mixed-methods. Interventions included food vouchers (n = 14) or food box/pantries (n = 5). Four studies allowed food items in addition to F/Vs. Six studies measured changes in FI and five reported a statistically significant decrease. Seven studies measured changes in F/V consumption and five reported a statistically significant increase. One study reported a statistically significant reduction in child BMI z-score. Most studies reported high feasibility. Few studies used high-quality methods. CONCLUSIONS: Pediatric PRx interventions show promising potential to reduce FI and improve diet quality and health-related outcomes. Future studies should utilize rigorous study designs and validated assessment tools to understand the impact of pediatric PRx on health. IMPACT: This work offers a summary of programmatic outcomes including retention, redemption, incentives, nutrition education, study design and quality limitations to help inform future work. We found positive impacts of pediatric produce prescriptions (PRx) on FI, F/V consumption, and nutritional knowledge and culinary skills. More high-quality, rigorous studies are needed to understand the best delivery and design of PRx and their impact on child behavior and health outcomes. This work provides support for the need for rigorous studies and the potential for PRx to play a role in multi-pronged strategies that address pediatric FI and diet-related disease.

4.
J Hand Surg Glob Online ; 5(6): 787-792, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38106953

RESUMO

Purpose: Carpometacarpal (CMC) arthroplasty is an effective surgical treatment to relieve pain and improve function for osteoarthritis of the CMC joint. The association between body mass index (BMI) and postoperative complications has been studied for other orthopedic procedures, including total knee arthroplasty, total hip arthroplasty, and total shoulder arthroplasty. However, BMI has not been studied as a risk factor for postoperative complications following CMC arthroplasty. The purpose of this study was to determine the postoperative complications associated with different categories of BMI following CMC arthroplasty. We hypothesized that increasing BMI is associated with more severe complications. Methods: The American College of Surgeons National Surgical Quality Improvement Program database was queried for all patients who underwent CMC arthroplasty between 2015 and 2020. Patient demographics, comorbidities, surgical characteristics, and 30-day postoperative complication data were collected. Patients were stratified into cohorts based on BMI as follows: underweight (BMI < 18.5 kg/m2), normal/reference (18.5 kg/m2 ≤ BMI < 30.0 kg/m2), obese (30.0 kg/m2 ≤ BMI < 35.0 kg/m2), severely obese (35.0 kg/m2 ≤ BMI < 40.0 kg/m2), and morbidly obese (BMI ≥ 40.0 kg/m2). Multivariate logistic regression was used to identify postoperative complications associated with each cohort. Results: In total, 6,432 patients were included in this study: 3,622 (56.3%) patients were included in the normal/reference cohort, 77 (1.2%) patients were included in the underweight cohort, 1,479 (23.0%) patients were included in the obese cohort, 718 (11.2%) patients were included in the severely obese cohort, and 536 (8.3%) patients were included in the morbidly obese cohort. The obese cohort was independently associated with a higher rate of superficial incisional surgical-site infection (odds ratio [OR], 2.11; 95% confidence interval [CI], 1.00-4.44; P = .050). The morbidly obese cohort was independently associated with readmission (OR, 3.35; 95% CI, 1.15-9.74; P = .026) and reoperation (OR, 3.40; 95% CI, 1.04-1.11; P = .043). Conclusions: Morbid obesity is a clinically significant predictor for readmission and reoperation within 30 days following CMC arthroplasty. Obesity is a clinically significant predictor for superficial incisional surgical-site infection within 30 days following CMC arthroplasty. Clinical relevance: A better understanding of BMI as a risk factor for postoperative complications may allow surgeons to improve preoperative risk stratification and patient counseling. Type of study/level of evidence: Prognostic III.

5.
Resuscitation ; 192: 109955, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37661012

RESUMO

BACKGROUND AND OBJECTIVES: Brain death (BD) occurs in 9-24% of successfully resuscitated out-of-hospital cardiac arrests (OHCA). To predict BD after OHCA, we developed a novel brain death risk (BDR) score. METHODS: We identified independent predictors of BD after OHCA in a retrospective, single academic center cohort between 2011 and 2021. The BDR score ranges from 0 to 7 points and includes: non-shockable rhythm (1 point), drug overdose as etiology of arrest (1 point), evidence of grey-white differentiation loss or sulcal effacement on head computed tomography (CT) radiology report within 24 hours of arrest (2 points), Full-Outline-Of-UnResponsiveness (FOUR) score of 0 (2 points), FOUR score 1-5 (1 point), and age <45 years (1 point). We internally validated the BDR score using k-fold cross validation (k = 8) and externally validated the score at an independent academic center. The main outcome was BD. RESULTS: The development cohort included 362OHCA patients, of whom 18% (N = 58) experienced BD. Internal validation provided an area under the receiving operator characteristic curve (AUC) (95% CI) of 0.931 (0.905-0.957). In the validation cohort, 19.8% (N = 17) experienced BD. The AUC (95% CI) was 0.849 (0.765-0.933). In both cohorts, a BDR score >4 was the optimal cut off (sensitivity 0.903 and 0.882, specificity 0.830 and 0.652, in the development and validation cohorts respectively). DISCUSSION: The BDR score identifies those at highest risk for BD after OHCA. Our data suggest that a BDR score >4 is the optimal cut off.


Assuntos
Reanimação Cardiopulmonar , Parada Cardíaca Extra-Hospitalar , Humanos , Pessoa de Meia-Idade , Parada Cardíaca Extra-Hospitalar/etiologia , Parada Cardíaca Extra-Hospitalar/terapia , Morte Encefálica , Estudos Retrospectivos , Fatores de Risco
6.
Resuscitation ; 188: 109832, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37178901

RESUMO

AIM: Early, accurate outcome prediction after out-of-hospital cardiac arrest (OHCA) is critical for clinical decision-making and resource allocation. We sought to validate the revised post-Cardiac Arrest Syndrome for Therapeutic hypothermia (rCAST) score in a United States cohort and compare its prognostic performance to the Pittsburgh Cardiac Arrest Category (PCAC) and Full Outline of UnResponsiveness (FOUR) scores. METHODS: This is a single-center, retrospective study of OHCA patients admitted between January 2014-August 2022. Area under the receiver operating curve (AUC) was computed for each score for predicting poor neurologic outcome at discharge and in-hospital mortality. We compared the scores' predictive abilities via Delong's test. RESULTS: Of 505 OHCA patients with all scores available, the medians [IQR] for rCAST, PCAC, and FOUR scores were 9.5 [6.0, 11.5], 4 [3, 4], and 2 [0, 5], respectively. The AUC [95% confidence interval] of the rCAST, PCAC, and FOUR scores for predicting poor neurologic outcome were 0.815 [0.763-0.867], 0.753 [0.697-0.809], and 0.841 [0.796-0.886], respectively. The AUC [95% confidence interval] of the rCAST, PCAC, and FOUR scores for predicting mortality were 0.799 [0.751-0.847], 0.723 [0.673-0.773], and 0.813 [0.770-0.855], respectively. The rCAST score was superior to the PCAC score for predicting mortality (p = 0.017). The FOUR score was superior to the PCAC score for predicting poor neurological outcome (p < 0.001) and mortality (p < 0.001). CONCLUSION: The rCAST score can reliably predict poor outcome in a United States cohort of OHCA patients regardless of TTM status and outperforms the PCAC score.


Assuntos
Reanimação Cardiopulmonar , Hipotermia Induzida , Parada Cardíaca Extra-Hospitalar , Humanos , Parada Cardíaca Extra-Hospitalar/terapia , Estudos Retrospectivos , Prognóstico
7.
J Physiol ; 601(22): 5011-5031, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35318675

RESUMO

Extended periods of bed rest and limb immobilization are required for healing post-injury or disease, yet disuse can result in significant muscle atrophy and decreased quality of life in older adults. Physical rehabilitation is commonly prescribed to recover these deficits, yet accumulation of reactive oxygen species and sustained rates of protein degradation persist during the rehabilitation period that can significantly delay or prevent recovery. Pericytes, considered the primary mesenchymal and vascular stromal cell in skeletal muscle, secrete beneficial factors that maintain baseline muscle mass, yet minimal information exists regarding the pericyte response to disuse and recovery. In the current study, single-cell RNA sequencing and functional assays were performed to demonstrate that pericytes in mouse skeletal muscle lose the capacity to synthesize antioxidants during disuse and recovery. This information was used to guide the design of a strategy in which healthy donor pericytes were stimulated with hydrogen peroxide (H2 O2 ) to produce small extracellular vesicles (sEVs) that effectively restored myofibre size in adult and aged muscle after disuse. Proteomic assessment detected 11 differentially regulated proteins in primed sEVs that may account for recovery of muscle, including proteins associated with extracellular matrix composition and anti-inflammatory and antioxidant processes. This study demonstrates that healthy H2 O2 -primed pericyte-derived sEVs effectively improve skeletal muscle recovery after immobilization, presenting a novel acellular approach to rebuild muscle mass in older adults after a period of disuse. KEY POINTS: Previous studies suggest that prolonged oxidative stress is a barrier to skeletal muscle recovery after a period of immobilization. In this study we demonstrate that muscle-resident perivascular stromal cells (pericytes) become dysfunctional and lack the capacity to mount an antioxidant defence after disuse in mice. Hydrogen peroxide treatment of healthy pericytes in vitro simulates the release of small extracellular vesicles (sEVs) that effectively recover skeletal muscle fibre size and extracellular matrix remodelling in young adult and aged mice after disuse. Pericyte-derived sEVs present a novel acellular strategy to recover skeletal muscle after disuse.


Assuntos
Peróxido de Hidrogênio , Qualidade de Vida , Camundongos , Animais , Peróxido de Hidrogênio/metabolismo , Antioxidantes/metabolismo , Proteômica , Músculo Esquelético/fisiologia , Atrofia Muscular/metabolismo
8.
Elife ; 112022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36255054

RESUMO

Mammalian carotid body arterial chemoreceptors function as an early warning system for hypoxia, triggering acute life-saving arousal and cardiorespiratory reflexes. To serve this role, carotid body glomus cells are highly sensitive to decreases in oxygen availability. While the mitochondria and plasma membrane signaling proteins have been implicated in oxygen sensing by glomus cells, the mechanism underlying their mitochondrial sensitivity to hypoxia compared to other cells is unknown. Here, we identify HIGD1C, a novel hypoxia-inducible gene domain factor isoform, as an electron transport chain complex IV-interacting protein that is almost exclusively expressed in the carotid body and is therefore not generally necessary for mitochondrial function. Importantly, HIGD1C is required for carotid body oxygen sensing and enhances complex IV sensitivity to hypoxia. Thus, we propose that HIGD1C promotes exquisite oxygen sensing by the carotid body, illustrating how specialized mitochondria can be used as sentinels of metabolic stress to elicit essential adaptive behaviors.


Assuntos
Corpo Carotídeo , Animais , Oxigênio/metabolismo , Células Quimiorreceptoras/metabolismo , Mitocôndrias/metabolismo , Hipóxia/metabolismo , Mamíferos/metabolismo
9.
Resuscitation ; 176: 150-158, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35562094

RESUMO

BACKGROUND: Assessment of brain injury severity is critically important after survival from cardiac arrest (CA). Recent advances in low-field MRI technology have permitted the acquisition of clinically useful bedside brain imaging. Our objective was to deploy a novel approach for evaluating brain injury after CA in critically ill patients at high risk for adverse neurological outcome. METHODS: This retrospective, single center study involved review of all consecutive portable MRIs performed as part of clinical care for CA patients between September 2020 and January 2022. Portable MR images were retrospectively reviewed by a blinded board-certified neuroradiologist (S.P.). Fluid-inversion recovery (FLAIR) signal intensities were measured in select regions of interest. RESULTS: We performed 22 low-field MRI examinations in 19 patients resuscitated from CA (68.4% male, mean [standard deviation] age, 51.8 [13.1] years). Twelve patients (63.2%) had findings consistent with HIBI on conventional neuroimaging radiology report. Low-field MRI detected findings consistent with HIBI in all of these patients. Low-field MRI was acquired at a median (interquartile range) of 78 (40-136) hours post-arrest. Quantitatively, we measured FLAIR signal intensity in three regions of interest, which were higher amongst patients with confirmed HIBI. Low-field MRI was completed in all patients without disruption of intensive care unit equipment monitoring and no safety events occurred. CONCLUSION: In a critically ill CA population in whom MR imaging is often not feasible, low-field MRI can be deployed at the bedside to identify HIBI. Low-field MRI provides an opportunity to evaluate the time-dependent nature of MRI findings in CA survivors.


Assuntos
Lesões Encefálicas , Parada Cardíaca , Hipóxia-Isquemia Encefálica , Encéfalo/patologia , Estado Terminal , Feminino , Parada Cardíaca/complicações , Parada Cardíaca/terapia , Humanos , Hipóxia-Isquemia Encefálica/diagnóstico por imagem , Hipóxia-Isquemia Encefálica/etiologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
10.
Biosens Bioelectron ; 210: 114333, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35525171

RESUMO

Noninvasive, wearable brain-computer interfaces (BCI) find limited use due to their obtrusive nature and low information. Currently available portable BCI systems are limited by device rigidity, bulky form factors, and gel-based skin-contact electrodes - and therefore more prone to noise and motion artifacts. Here, we introduce virtual reality (VR)-enabled split-eye asynchronous stimulus (SEAS) allowing a target to present different stimuli to either eye. This results in unique asynchronous stimulus patterns measurable with as few as four EEG electrodes, as demonstrated with improved wireless soft electronics for portable BCI. This VR-embedded SEAS paradigm demonstrates potential for improved throughput with a greater number of unique stimuli. A wearable soft platform featuring dry needle electrodes and shielded stretchable interconnects enables high throughput decoding of steady-state visually evoked potentials (SSVEP) for a text spelling interface. A combination of skin-conformal electrodes and soft materials offers high-quality recordings of SSVEP with minimal motion artifacts, validated by comparing the performance with a conventional wearable system. A deep-learning algorithm provides real-time classification, with an accuracy of 78.93% for 0.8 s and 91.73% for 2 s with 33 classes from nine human subjects, allowing for a successful demonstration of VR text spelling and navigation of a real-world environment. With as few as only four data recording channels, the system demonstrates a highly competitive information transfer rate (243.6 bit/min). Collectively, the VR-enabled soft system offers unique advantages in wireless, real-time monitoring of brain signals for portable BCI, neurological rehabilitation, and disease diagnosis.


Assuntos
Técnicas Biossensoriais , Interfaces Cérebro-Computador , Realidade Virtual , Eletrodos , Eletroencefalografia/métodos , Humanos
11.
J Neurosci ; 42(18): 3716-3732, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35361703

RESUMO

The limited ability for axonal repair after spinal cord injury underlies long-term functional impairment. Dual leucine-zipper kinase [DLK; MAP kinase kinase kinase 12; MAP3K12] is an evolutionarily conserved MAP3K implicated in neuronal injury signaling from Caenorhabditis elegans to mammals. However, whether DLK or its close homolog leucine zipper kinase (LZK; MAP3K13) regulates axonal repair in the mammalian spinal cord remains unknown. Here, we assess the role of endogenous DLK and LZK in the regeneration and compensatory sprouting of corticospinal tract (CST) axons in mice of both sexes with genetic analyses in a regeneration competent background provided by PTEN deletion. We found that inducible neuronal deletion of both DLK and LZK, but not either kinase alone, abolishes PTEN deletion-induced regeneration and sprouting of CST axons, and reduces naturally-occurring axon sprouting after injury. Thus, DLK/LZK-mediated injury signaling operates not only in injured neurons to regulate regeneration, but also unexpectedly in uninjured neurons to regulate sprouting. Deleting DLK and LZK does not interfere with PTEN/mTOR signaling, indicating that injury signaling and regenerative competence are independently controlled. Together with our previous study implicating LZK in astrocytic reactivity and scar formation, these data illustrate the multicellular function of this pair of MAP3Ks in both neurons and glia in the injury response of the mammalian spinal cord.SIGNIFICANCE STATEMENT Functional recovery after spinal cord injury is limited because of a lack of axonal repair in the mammalian CNS. Dual leucine-zipper kinase (DLK) and leucine zipper kinase (LZK) are two closely related protein kinases that have emerged as regulators of neuronal responses to injury. However, their role in axonal repair in the mammalian spinal cord has not been described. Here, we show that DLK and LZK together play critical roles in axonal repair in the mammalian spinal cord, validating them as potential targets to promote repair and recovery after spinal cord injury. In addition to regulating axonal regeneration from injured neurons, both kinases also regulate compensatory axonal growth from uninjured neurons, indicating a more pervasive role in CNS repair than originally anticipated.


Assuntos
Zíper de Leucina , MAP Quinase Quinase Quinases/metabolismo , Traumatismos da Medula Espinal , Animais , Axônios/fisiologia , Feminino , Leucina/metabolismo , MAP Quinase Quinase Quinases/genética , Masculino , Mamíferos , Camundongos , Regeneração Nervosa/fisiologia , Tratos Piramidais/fisiologia
12.
J Emerg Med ; 60(2): 220-222, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33588993

RESUMO

BACKGROUND: Emergency physicians frequently evaluate patients with vision changes. The differential for this chief symptom is broad. We present a unique cause of a fixed scotoma that started while the patient was running sprints. CASE REPORT: The patient described a bright central scotoma that later became a dark oblique line across her central vision. This painless defect moved predictably with eye movements. Ocular ultrasonography was performed and revealed a well-demarcated hyperechoic lesion in the posterior segment of the right eye. There was no similar lesion found in her left eye. In consultation with ophthalmology, the patient's history and examination were consistent with valsalva retinopathy. To our knowledge, this is only the second published case of valsalva retinopathy/premacular hemorrhage identified on ocular ultrasonography in emergency medicine literature. In this article, we further expand on management and provide correlating fundoscopic images. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Emergency physicians frequently evaluate patients with visual changes. Valsalva retinopathy is a rare cause of a visual scotoma that can be diagnosed through history and ultrasound. It often resolves over weeks to months without intervention. However, it does require urgent ophthalmologic evaluation to rule out peripheral retinal tears, which may require laser retinopexy or surgical management.


Assuntos
Hemorragia Retiniana , Manobra de Valsalva , Olho , Feminino , Humanos , Hemorragia Retiniana/diagnóstico , Hemorragia Retiniana/etiologia , Ultrassonografia
13.
Sci Rep ; 10(1): 19319, 2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-33168868

RESUMO

Regular exercise is crucial for maintaining cognitive health throughout life. Recent evidence suggests muscle contractions during exercise release factors into the blood which cross into the brain and stimulate adult hippocampal neurogenesis. However, no study has tested whether muscle contractions alone are sufficient to increase adult hippocampal neurogenesis and improve behavioral performance. Adult male, C57BL/6J mice were anesthetized and exposed to bilateral hind limb muscle contractions (both concentric and eccentric) via electrical stimulation (e-stim) of the sciatic nerve twice a week for 8 weeks. Each session lasted approximately 20 min and consisted of a total of 40 muscle contractions. The control group was treated similarly except without e-stim (sham). Acute neuronal activation of the dentate gyrus (DG) using cFos immunohistochemistry was measured as a negative control to confirm that the muscle contractions did not activate the hippocampus, and in agreement, no DG activation was observed. Relative to sham, e-stim training increased DG volume by approximately 10% and astrogliogenesis by 75%, but no difference in neurogenesis was detected and no improvement in behavioral performance was observed. E-stim also increased astrogliogenesis in CA1/CA2 hippocampal subfields but not in the cortex. Results demonstrate that muscle contractions alone, in absence of DG activation, are sufficient to increase adult hippocampal astrogliogenesis, but not neurogenesis or behavioral performance in mice.


Assuntos
Astrócitos/fisiologia , Comportamento Animal , Estimulação Elétrica , Membro Posterior/fisiologia , Hipocampo/metabolismo , Contração Muscular , Neurogênese , Animais , Giro Denteado/fisiologia , Medo , Imuno-Histoquímica , Masculino , Aprendizagem em Labirinto , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/fisiologia , Condicionamento Físico Animal
14.
Prog Neurobiol ; 195: 101844, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32497564

RESUMO

In the attention schema theory (AST), the brain constructs a schematic, simplified model of attention. The model is associated with three cognitive processes: a model of one's own attention contributes to the endogenous control of attention, a model of the attention of others contributes to theory of mind, and the contents of these models leads to the common human claim that we contain a non-physical consciousness or awareness inside us. Because AST is a control-engineering style theory, it can make specific predictions in complex situations. Here, over six experiments, we examined interactions between attention and awareness to test predictions of AST. Participants performed a visual task in which a cue stimulus affected their attention, as measured by their reactions to a subsequent target stimulus. The task measured both exogenous attention drawn to the cue and endogenous attention directed to a target location predicted by the cue. When participants were not aware that the cue predicted the target, both exogenous and endogenous attention effects remained. In contrast, when participants were not visually aware of the cue itself, the exogenous attention effect remained and the endogenous effect was impaired. In an additional two experiments, when participants learned an implicit shift of attention, the learning generalized from trained spatial locations to adjacent, untrained locations. Each of these findings matched predictions of AST. The results support the interpretation that attention control relies partly on an internal model that is responsible for claims of awareness.


Assuntos
Atenção/fisiologia , Conscientização/fisiologia , Estado de Consciência/fisiologia , Função Executiva/fisiologia , Desempenho Psicomotor/fisiologia , Percepção Visual/fisiologia , Adolescente , Adulto , Sinais (Psicologia) , Feminino , Humanos , Masculino , Teoria Psicológica , Adulto Jovem
15.
J R Soc Interface ; 16(150): 20180456, 2019 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-30958155

RESUMO

Autorotation of botanical samaras, with a consequent reduction in their rate of descent, increases dispersal range in the presence of horizontal winds. Samaras in initial free fall from rest pass through a brief transitional phase prior to reaching their minimum rate of descent and stable autorotation. By contrast, intense wind gusts and elastic recoil of tree branches can produce impulsive samara detachment and accelerate them rapidly through the air. Here, we investigate the autorotation of maple samaras when launched with a high initial impulse. Norway maple seeds catapulted either vertically or horizontally at approximately 9 m s-1 exhibited remarkably high and rapid decelerations (10-15 g) and reached a near-zero translational speed in less than 150 ms. The initial rotational frequency of catapulted seeds was up to four times greater than that ultimately reached during steady-state autorotation. These helicopter seeds thus transiently produce very high lift forces (at Reynolds numbers near approximately 104) that act to enhance aerial transport. These findings are relevant to the modelling of long-distance seed dispersal in unsteady flows, as well as to the design of deceleration mechanisms based on lift generation, rather than drag-based devices such as parachutes.


Assuntos
Acer , Modelos Biológicos , Dispersão de Sementes/fisiologia , Sementes , Vento , Acer/anatomia & histologia , Acer/fisiologia , Sementes/anatomia & histologia , Sementes/fisiologia
17.
Exp Neurol ; 309: 32-43, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30055160

RESUMO

Recovery from injury to the central nervous system (CNS) is limited in the mammalian adult. Nonetheless, some degree of spontaneous recovery occurs after partial CNS injury. Compensatory axonal growth from uninjured neurons, termed sprouting, contributes to this naturally occurring recovery process and can be modulated by molecular intervention. Extensive studies have depicted a long-held hypothesis that oligodendrocyte-derived Nogo restricts axonal sprouting and functional recovery after CNS injury. However, cell type-specific function of Nogo in compensatory sprouting, spinal axon repair or functional recovery after CNS injury has not been reported. Here we present data showing that inducible, cell type-specific deletion of Nogo from oligodendrocytes led to a ~50% increase in the compensatory sprouting of corticospinal tract (CST) axons in the cervical spinal cord after unilateral pyramidotomy in mice. In contrast to a previously proposed growth-promoting role of neuronal Nogo in the optic nerve, deleting neuronal Nogo did not significantly affect CST axon sprouting in the spinal cord. Sprouting axons were associated with the expression of synaptic marker VGLUT1 in both the oligodendrocytic Nogo deletion and control mice. However, we did not detect any functional improvement in fine motor control associated with the increased sprouting in oligodendrocytic Nogo deletion mice. These data show for the first time with genetic evidence that Nogo specifically expressed by oligodendrocytes restricts compensatory sprouting after CNS injury, supporting a longstanding but heretofore untested hypothesis. While implicating a focus on sprouting as a repair mechanism in the translational potential of targeting the myelin inhibitory pathway, our study illustrates the challenge to harness enhanced structural plasticity for functional improvement.


Assuntos
Doenças do Sistema Nervoso Central/patologia , Neurônios/metabolismo , Proteínas Nogo/metabolismo , Oligodendroglia/metabolismo , Tratos Piramidais/patologia , Fatores Etários , Animais , Axônios , Biotina/análogos & derivados , Biotina/metabolismo , Dextranos/metabolismo , Modelos Animais de Doenças , Privação de Alimentos , Lateralidade Funcional , Substância Cinzenta/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurogênese , Neurônios/patologia , Proteínas Nogo/genética , Recuperação de Função Fisiológica , Transdução Genética , Proteína Vesicular 1 de Transporte de Glutamato/metabolismo
18.
Korean J Neurotrauma ; 13(1): 29-33, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28512615

RESUMO

The clinical manifestations of vertebral artery (VA) injury (VAI) after cervical trauma range from asymptomatic to fatal cerebral infarction. Thrombotic occlusion and embolization to the distal arteries can cause cerebellar and brain stem infarction within days after trauma. We report a 64-year-old man who underwent arthrodesis surgery for C1 and C2 fractures. He had left VAI at the C2 transverse foramen site but was asymptomatic. The patient experiences brainstem and cerebellar infarction 3 months after injury to the VA, and we are here to discuss the treatment of VAI after cervical trauma.

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