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1.
J Sport Rehabil ; : 1-8, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38688463

RESUMO

CONTEXT: Sports-related concussions are commonly occurring injuries as a result of sports and recreation that may cause alterations in brain functioning. It is important to be able to evaluate the impact of these injuries on function to manage the injury recovery and ensure recovery. Recent literature suggests the use of objective evaluation strategies in a multifaceted approach to evaluate and manage these injuries. It is important to understand the relationships between the assessments and how best to utilize each assessment. The purpose of this study was to investigate if relationships exist between measures of vestibular function at baseline in assessments that may be used following sports-related concussions. Additionally, a secondary purpose was to determine if self-reported symptoms were related to performance on the assessments. This study aimed to identify if these assessments measured independent functions of the vestibulo-ocular reflex or if some redundancy existed among the assessment strategies. DESIGN: A cross-sectional study design was used in a cohort of collegiate athletes ages 18-24. METHODS: Participants completed demographics questionnaires, the Post-Concussion Symptom Scale, Gaze Stabilization Test, and Concussion Balance Test. Spearman rho correlations were used to examine the relationships between the measures. RESULTS: One hundred and thirty-five collegiate athletes (82 males and 53 females) were included, representative of 3 sports (cheerleading, soccer, and football) with a mean age of 19.77 (1.42) years old. There were weak to moderate, significant relationships between measures of Gaze Stabilization Test and Concussion Balance Test errors (r = .20-.31, P = .001-.03). CONCLUSIONS: The direction of these relationships indicated that greater Concussion Balance Test errors were associated with greater Gaze Stabilization Test performance. These relationships may be attributed to the difficulty created by the foam conditions and the integration of more complex sensory tasks required to maintain balance during the more difficult conditions.

2.
J Sport Rehabil ; : 1-9, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38508176

RESUMO

CONTEXT: Concussion evaluations include a multifaceted approach; however, individual differences can influence test score interpretations and validity. Social determinants of health (SDoH) differentially affect disease risk and outcomes based upon social and environmental characteristics. Efforts to better define, diagnose, manage, and treat concussion have increased, but minimal efforts have focused on examining SDoH that may affect concussion recovery. OBJECTIVE: This review examined previous research that examined the effect of SDoH on concussion recovery of athletes. EVIDENCE ACQUISITION: CINAHL, MEDLINE, PsycInfo, and SPORTDiscus databases were used to search the terms "concussion" AND "recovery," "youth, adolescent, teen and/or adult," and "social determinants of health" and variations of these terms. The evidence level for each study was evaluated using the 2011 Oxford Center for Evidence-Based Medicine Guide. EVIDENCE SYNTHESIS: Seven thousand nine hundred and twenty-one articles were identified and screened for inclusion. Five studies met the inclusion criteria and were included in this systematic review. Using the Downs and Black Quality Index, the studies included in this review were deemed high quality. CONCLUSION: Though limited literature exists, there is preliminary evidence to suggest that SDoH (specifically, economic stability, education access and quality, and social and community context) may have an impact on the clinical recovery from concussion. The dimensions evaluated varied between studies and the results were inconsistent. No single factor consistently affected clinical recovery; however, private insurance and race appear to have an association with the speed of recovery. Unfortunately, the potential intersection of these variables and other preinjury factors limits the ability to make clear recommendations. While most of the studies in this review are retrospective in nature, future efforts should focus on training clinicians to prospectively evaluate the effect of SDoH on concussion recovery and injury outcomes. Funding and registration for this systematic review were not obtained nor required.

3.
An Acad Bras Cienc ; 95(4): e20191259, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37729295

RESUMO

The present study aims to structurally and histochemically characterize the Gymnotus carapo tegument. 30 specimens were captured and slaughtered by spinal section with anesthesia. The observation was carried out with a stereoscopic microscope and the body surface was photographed. Fragments of the dorsal, ventral and lateral region were fixed in Bouin's solution for 12 hours and subsequently preserved in 70% alcohol. They were subsequently observed in the scanning electron microscope (SEM). The preparation for SEM was performed following the standardized protocol. Histological preparations were made, and the cuts were colored with H-E, PAS and Coomassie Blue. The images were obtained in an Olympus BX41-ENUTV-4 microscope. From the observations in SEM a plain tegument with pores of different sizes could be evidenced. The scales of the different regions of the body have different ornaments. Microscopically it was composed of a stratified non-keratinized epithelium consisting of two types of morphologically distinct cells: epidermal cells and mucous cells (PAS-Commassie Blue positive). Under the epithelium there is a layer of dense irregular connective tissue with associated chromatophores and more deeply scales. These analyzes are the basis for future studies that will focus on elucidating the events related to integumentary healing in this species.


Assuntos
Anestesia , Gimnotiformes , Animais , Peixes , Pele , Etanol
4.
Res Sports Med ; 31(4): 473-481, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34711090

RESUMO

The purpose of this study was to compare visuomotor reaction time (VMRT) in collegiate athletes based on ankle sprain history. Participants included athletes with ankle sprain history (n = 18) and athletes with no ankle sprain history (n = 33). Participants completed an upper-extremity VMRT task which was comprised of eight wireless light-emitting diode sensors. The difference between reaction time (sec) and the number of "Hits" and "Misses" were compared between groups. The ankle sprain history group had significantly slower VMRT compared to the no ankle sprain history group with moderate effect sizes. However, there was no difference in the number of "Hits" or "Misses" between groups, despite observing moderate effect sizes. This result suggests that VMRT may be a potential target for prevention and rehabilitation strategies in individuals with ankle sprains. However, further research is needed to better understand the role of VMRT on the risk of ankle sprains.


Assuntos
Traumatismos do Tornozelo , Traumatismos em Atletas , Entorses e Distensões , Humanos , Tempo de Reação , Atletas
5.
J Sci Med Sport ; 25(1): 64-69, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34446366

RESUMO

OBJECTIVES: Poorer neurocognitive performance may increase lower extremity injury risk due to alterations in biomechanics. However, it is unclear if poorer neurocognitive function may be associated with altered dynamic postural stability. Therefore, the purpose of this study was to investigate the relationship between neurocognitive performance and dynamic postural stability in healthy collegiate athletes. DESIGN: Cross-sectional cohort. METHODS: Forty-five Division-I collegiate athletes (21 males, 24 females; age: 19.69 ±â€¯1.50) completed neurocognitive assessments from the NIH Toolbox® (NIHTB). Three groups were established from the NIHTB composite score: high performers (HP), moderate performers (MP), and low performers (LP). Additionally, participants completed a dynamic hop-to-stabilization task. Accelerometer and gyroscopic data were recorded during landing through an inertial measurement unit (IMU) on the participant's low back. The root mean squared (RMS) of the accelerometer and gyroscope was calculated for the orthogonal planes and the resultant vector. Group differences for demographic variables, NIHTB composite scores, and IMU based measures were analyzed with one-way ANOVAs with Bonferroni post hoc analyses were performed. Cohen's d effect sizes were also calculated. RESULTS: Post hoc tests determined the LP group had higher vertical acceleration RMS values (p = 0.013, d = -0.85) and lower anteroposterior acceleration RMS values (p = 0.005, d = 0.95) compared to the HP group. CONCLUSIONS: Neurocognitive performance may influence dynamic postural stability strategies in athletes. Higher neurocognitive performers may use different approaches to perform difficult postural tasks by adopting strategies associated with lower vertical and higher anteroposterior acceleration compared to lower neurocognitive performers.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Adolescente , Adulto , Atletas , Fenômenos Biomecânicos , Estudos Transversais , Feminino , Humanos , Masculino , Equilíbrio Postural , Adulto Jovem
6.
Sports Med ; 51(4): 737-757, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33400218

RESUMO

BACKGROUND: Recent literature has identified that the vestibular system is often involved following a sport-related concussion. Furthermore, the consequences of vestibular and ocular/oculomotor involvement have been explored and identified as potential predictors for prolonged recovery. Although vestibular and ocular/oculomotor involvement is common following head injury, the clinical assessment strategies for vestibular function are less commonly practiced in the sports medicine setting and have limited research. Therefore, despite the suspected link between vestibular consequences of concussion and prolonged recovery time, there is limited understanding on how these consequences affect outcomes following concussion and how to properly assess these functions. OBJECTIVES: The objectives of this scoping review were to: (1) outline the current clinical assessment strategies for vestibular and ocular/oculomotor function in sports medicine to identify the best strategies for assessment, and (2) investigate the evidence regarding the influence of vestibular and ocular/oculomotor function on outcomes for patients with a sport-related concussion. METHODS: Two separate and independent reviews of the current literature were conducted to provide evidence for each specified objective. Studies for potential inclusion were identified through electronic database searches. Inclusion criteria for each objective were used to identify the most effective studies and inquiries to address the outlined objectives. RESULTS: The identified and included studies provided evidence-based information regarding the current assessment strategies as well as outcomes following concussion. CONCLUSION: Despite agreement among studies, there was limited evidence to support each aim, identifying a need for further exploration into these objectives.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Medicina Esportiva , Esportes , Traumatismos em Atletas/diagnóstico , Concussão Encefálica/diagnóstico , Humanos
7.
J Sport Rehabil ; 30(5): 828-831, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33027762

RESUMO

CONTEXT: Fast visuomotor reaction time (VMRT), the time required to recognize and respond to sequentially appearing visual stimuli, allows an athlete to successfully respond to stimuli during sports participation, while slower VMRT has been associated with increased injury risk. Light-based systems are capable of measuring both upper- and lower-extremity VMRT; however, the reliability of these assessments are not known. OBJECTIVE: To determine the reliability of an upper- and lower-extremity VMRT task using a light-based trainer system. DESIGN: Reliability study. SETTING: Laboratory. Patients (or Other Participants): Twenty participants with no history of injury in the last 12 months. METHODS: Participants reported to the laboratory on 2 separate testing sessions separated by 1 week. For both tasks, participants were instructed to extinguish a random sequence of illuminated light-emitting diode disks, which appeared one at a time as quickly as possible. Participants were provided a series of practice trials before completing the test trials. VMRT was calculated as the time in seconds between target hits, where higher VMRT represented slower reaction time. MAIN OUTCOME MEASURES: Separate intraclass correlation coefficients (ICCs) with corresponding 95% confidence intervals (CIs) were calculated to determine test-retest reliability for each task. The SEM and minimal detectable change values were determined to examine clinical applicability. RESULTS: The right limb lower-extremity reliability was excellent (ICC2,1 = .92; 95% CI, .81-.97). Both the left limb (ICC2,1 = .80; 95% CI, .56-.92) and upper-extremity task (ICC2,1 = .86; 95% CI, .65-.95) had good reliability. CONCLUSIONS: Both VMRT tasks had clinically acceptable reliability in a healthy, active population. Future research should explore further applications of these tests as an outcome measure following rehabilitation for health conditions with known VMRT deficits.


Assuntos
Terapia por Exercício/métodos , Terapia por Exercício/normas , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Terapia por Exercício/instrumentação , Humanos , Extremidade Inferior , Reprodutibilidade dos Testes , Extremidade Superior
8.
J Sport Rehabil ; 30(2): 327-332, 2020 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-32791494

RESUMO

Clinical Scenario: Neurocognitive performance may put individuals at a greater risk for lower-extremity musculoskeletal injuries. Research has observed the relationship between lower-extremity musculoskeletal injury and baseline neurocognitive performance; however, the understanding of this relationship is lacking. Exploring this relationship may give further insight into musculoskeletal injury and provide innovative directions for musculoskeletal injury prevention. Clinical Question: Is there a relationship between neurocognitive performance and lower-extremity biomechanics during a jumping or cutting task in healthy adult athletes? Summary of Key Findings: The literature was searched for articles that examined the relationship of a baseline neurocognitive test and a biomechanical analysis following a sports-related task. A total of 3 cross-sectional articles were included. All 3 studies concluded that poorer neurocognitive performance was associated with biomechanical faults that are linked to increased risk or rate of lower-extremity musculoskeletal injury. Clinical Bottom Line: Based on the evidence included, there is a moderate-level evidence to support the relationship between neurocognition and lower-extremity biomechanics in healthy adult athletes. Strength of Recommendation: In accordance with the van Tulder approach, there is a moderate level of evidence due to consistent findings from a combination of high- and limited-quality articles.


Assuntos
Traumatismos em Atletas , Esportes , Adulto , Atletas , Fenômenos Biomecânicos , Estudos Transversais , Humanos , Extremidade Inferior/lesões
9.
Physiol Meas ; 41(4): 045002, 2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32176875

RESUMO

OBJECTIVE: To investigate the influence of cognitive dual-tasks on dynamic postural sway variability, measured with a single inertial measurement unit, in healthy collegiate athletes during dual-task gait. APPROACH: Thirty-four athletes ambulated down and back a 10-meter course. Root mean square values of postural sway acceleration were calculated for four sway-planes. Single and dual-task trial times were calculated from gait initiation to termination. Single and dual-task root mean square values were compared using Wilcoxon signed rank tests for each sway plane to determine significance. The relative difference between each sway measures and trial times for single and dual-task gait (i.e. dual-task cost was calculated). Spearman's correlation was used to analyze the association between dual-task cost of sway and trial time data. MAIN RESULTS: During dual-task conditions, participants ambulated slower and demonstrated a significant reduction in root mean square sway in all planes of motion. The greatest decreases were in the medial-lateral (Z = -4.83, p < 0.001, ES = -0.83) and superior-inferior planes (Z = -4.93, p < 0.001, ES = -0.85). Increased trial time cost was associated with a decrease in dual-task cost of postural sway (p < 0.05). SIGNIFICANCE: Performing a cognitive task while ambulating decreased postural sway variability in task-relevant planes of motion compared to single-task conditions. Reduced dual-task cost of sway variability during gait was associated with maintained trial times between single and dual-tasks. These data support the use of instrumented dual-task gait assessment to evaluate postural sway variability.


Assuntos
Cognição , Marcha/fisiologia , Monitorização Fisiológica/métodos , Equilíbrio Postural/fisiologia , Adolescente , Atletas/psicologia , Feminino , Humanos , Masculino
10.
Fish Physiol Biochem ; 45(3): 1051-1065, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31089991

RESUMO

The aim of this study was to assess the leaf aqueous extract composition of Serjania marginata and the effects of its inclusion on the diet of Nile tilapia (Oreochromis niloticus), with respect to the activity of digestive enzymes and enzymes associated with the metabolism of the liver and intestine and liver histopathology. Fish (initial mean weight, 54.36 ± 17.04 g) were divided into groups: fasting (without feeding), control (commercial feed), and treatment (commercial feed with leaf aqueous extract of Serjania marginata), and in each aquarium, there were five individuals and the fish fed ad libitum for 15 days. Treatment fish had ingested on average 224.3 mg of extract/kg of fish/day. In the extract analysis by mass spectrometry, quercitrin, isoquercitrin, A-type proanthocyanidin trimer, and quinic acid were identified. In the enzymatic activity, fish from the treatment group showed higher level of alkaline phosphatase, while the hepatotoxic markers (AST and ALT) and levels of lipase, amylase, and nonspecific protease did not differ (p > 0.05). In liver histopathological analysis, it was observed that fish from the treatment showed normal structure, while abnormalities were associated with control (fibrosis, loss of cordonal architecture, vacuolated hepatocytes with nucleus displaced to the periphery) and fasting (reduction in hepatocyte size and sinusoidal space). The intestine histopathology evidenced that the extract favored the development of goblet cells and intestinal fold height. The results indicated that the leaf aqueous extract of S. marginata assists in the structural maintenance of the liver and intestine and stimulates intestinal alkaline phosphatase production in Nile tilapia, suggesting that the identified compounds act on the liver and intestine, showing hepatoprotective effects and stimulating intestinal digestion.


Assuntos
Ciclídeos/metabolismo , Fígado/efeitos dos fármacos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Substâncias Protetoras/farmacologia , Sapindaceae/química , Estômago/efeitos dos fármacos , Animais , Suplementos Nutricionais , Fígado/enzimologia , Extratos Vegetais/química , Substâncias Protetoras/química
11.
J Sport Rehabil ; 28(4): 368-372, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30987519

RESUMO

Context: During thoroughbred races, jockeys are placed in potentially injurious situations, often with inadequate safety equipment. Jockeys frequently sustain head injuries; therefore, it is important that they wear appropriately certified helmets. Objective: The goals of this study are (1) to perform impact attenuation testing according to ASTM F1163-15 on a sample of equestrian helmets commonly used by jockeys in the United States and (2) to quantify headform acceleration and residual crush after repeat impacts at the same location. Participants and Design: Seven helmet models underwent impact attenuation testing according to ASTM F1163-15. A second sample of each helmet model underwent repeat impacts at the crown location for a total of 4 impacts. Setting: Laboratory. Intervention: Each helmet was impacted against a flat and equestrian hazard anvil. Main Outcome Measures: Headform acceleration was recorded during all impact and computed tomography scans were performed preimpact and after impacts 1 and 4 on the crown to quantify liner thickness. Results: Four helmets had 1 impact that exceeded the limit of 300g. During the repeated crown impacts, acceleration remained below 300g for the first and second impacts for all helmets, while only one helmet remained below 300g for all impacts. Foam liner thickness was reduced between 5% and 39% after the first crown impact and between 33% and 70% after the fourth crown impact. Conclusions: All riders should wear a certified helmet and replace it after sustaining a head impact. Following an impact, expanded polystyrene liners compress, and their ability to attenuate head acceleration during subsequent impacts to the same location is reduced. Replacing an impacted helmet may reduce a rider's head injury risk.


Assuntos
Dispositivos de Proteção da Cabeça/normas , Teste de Materiais , Equipamentos Esportivos/normas , Aceleração , Traumatismos Craniocerebrais/prevenção & controle , Humanos
12.
J Emerg Trauma Shock ; 11(3): 225-227, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30429633

RESUMO

A 16-year-old male developed palpitations immediately following chest impact with a soccer ball. The patient was noted to have ventricular flutter in a delayed presentation that was successfully treated. While ventricular fibrillation is the predominant arrhythmia following commotio cordis, ventricular flutter may occur as well. Ventricular flutter may be better tolerated in a young athletic individual with structurally normal heart and may lead to a delayed presentation.

13.
Brain Inj ; 32(12): 1566-1575, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30047794

RESUMO

OBJECTIVE: The impact that visual perturbation has on upright postural stability in an athlete with a concussion has not been established. The present study aimed to characterize the influence that visual perturbation stimuli have on upright balance among athletes with acute concussions. DESIGN: A 2X2X2 repeated measure designed was used. METHOD: The present study examined the influence visual perturbation has on individuals suffering from an acute concussion. Fourteen participants (7 with a concussion and 7 matched controls) underwent various balance assessments with and without visual perturbation. RESULTS: Overall, athletes with acute concussions demonstrated impairments in balance 24-48 hours following a concussion. However, when assessed using a visual perturbation task, athletes with acute concussions demonstrated improved balance, while control subjects did not show any significant changes during the same visual perturbation task. CONCLUSION: An athlete's ability to disregard visual perturbation stimuli is imperative for successful participation in sports. Due to the observed alterations in balance when given a visual perturbation task, it is suggested that athletes with acute concussions place more attention on the balance task and may disregard other less meaningful tasks.


Assuntos
Traumatismos em Atletas/fisiopatologia , Concussão Encefálica/fisiopatologia , Testes Neuropsicológicos , Equilíbrio Postural/fisiologia , Medicina Esportiva , Percepção Visual/fisiologia , Adaptação Fisiológica , Adolescente , Atletas , Traumatismos em Atletas/reabilitação , Fenômenos Biomecânicos , Concussão Encefálica/reabilitação , Feminino , Humanos , Masculino , Propriocepção/fisiologia , Adulto Jovem
14.
J Sport Rehabil ; 27(5): 1-4, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29809102

RESUMO

CONTEXT: Reaction time (RT) is crucial to athletic performance. Therefore, when returning athletes to play following injury, it is important to evaluate RT characteristics ensuring a safe return. The Dynavision D2® system may be utilized as an assessment and rehabilitation aid in the determination of RT under various levels of cognitive load. Previous research has demonstrated good reliability of simple protocols when assessed following a 24- to 48-hour test-retest window. Expanding reliable test-retest intervals may further refine novel RT protocols for use as a diagnostic and rehabilitation tool. OBJECTIVE: To investigate the test-retest reliability of a battery of 5 novel RT protocols at different time intervals. DESIGN: Repeated measures/reliability. SETTING: Interdisciplinary sports medicine research laboratory. PARTICIPANTS: Thirty healthy individuals. METHODS: Participants completed a battery of protocols increasing in difficulty in terms of reaction speed requirement and cognitive load. Prior to testing, participants were provided 3 familiarization trials. All protocols required participants to hit as many lights as quickly as possible in 60 seconds. After completing the initial testing session (session 1), participants waited 1 hour before completing the second session (session 2). Approximately 2 weeks later (average 14 [4] d), the participants completed the same battery of tasks for the third session (session 3). MAIN OUTCOME MEASURES: The intraclass correlation coefficient, standard error of measurement, minimal detectable change, and repeated-measures analysis of variance were calculated for RT. RESULTS: The intraclass correlation coefficient values for each of the 5 protocols illustrated good to excellent reliability between sessions 1, 2, and 3 (.75-.90). There were no significant differences across time points (F < 0.105, P > .05). CONCLUSIONS: The 1-hour and 14-day test-retest intervals are reliable for clinical assessment, expanding the time frames previously reported in the literature of when assessments can be completed reliably. This study provides novel protocols that challenge cognition in unique ways.


Assuntos
Cognição , Desempenho Psicomotor , Tempo de Reação , Reprodutibilidade dos Testes , Adulto , Desempenho Atlético , Feminino , Humanos , Masculino , Adulto Jovem
15.
Artigo em Inglês | MEDLINE | ID: mdl-28906480

RESUMO

This study aimed to further our understanding of a characteristic of Community Resilience known as Disaster Governance. Three attributes of Disaster Governance-redundancy, diversity, and overlap-were studied in four coastal towns in southern Chile that are at risk of tsunamis. Overall, we explored how different spatial structures of human settlements influence Disaster Governance. Using the Projective Mapping Technique, the distribution of emergency institutions (N = 32) and uses given to specific sites (e.g., for refuge, sanitary purposes and medical attention) were mapped. Content and GIS analyses (Directional Distribution and Kernel Density Index) were used to explore the dispersion and concentration of institutions and uses in each town. Disaster Governance was found to be highly influenced by decisions taken during regional, urban, and emergency planning. Governance is better in towns of higher order in the communal hierarchical structure. Most of the emergency institutions were found to be located in central and urban areas, which, in turn, assures more redundancy, overlap, and diversity in governance in the event of a tsunami. Lack of flexibility of emergency plans also limits governance in rural and indigenous areas. While the spatial relationships found in this study indicate that urban sectors have better Disaster Governance than rural and indigenous sectors, the influence of resource availability after tsunamis, the role and responsibility of different levels of governments, and the politics of disaster also play an important role in Disaster Governance for determining Community Resilience. These findings shed light on emergency planning and aspects of the Disaster Management cycle.


Assuntos
Planejamento em Desastres/métodos , Desastres , Tsunamis , Chile , Planejamento de Cidades , Participação da Comunidade , Governo Federal , Humanos , Política , Fatores Socioeconômicos
16.
JCI Insight ; 2(11)2017 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-28570269

RESUMO

Mechanical ventilation is necessary to support patients with acute lung injury, but also exacerbates injury through mechanical stress-activated signaling pathways. We show that stretch applied to cultured human cells, and to mouse lungs in vivo, induces robust expression of metallothionein, a potent antioxidant and cytoprotective molecule critical for cellular zinc homeostasis. Furthermore, genetic deficiency of murine metallothionein genes exacerbated lung injury caused by high tidal volume mechanical ventilation, identifying an adaptive role for these genes in limiting lung injury. Stretch induction of metallothionein required zinc and the zinc-binding transcription factor MTF1. We further show that mouse dietary zinc deficiency potentiates ventilator-induced lung injury, and that plasma zinc levels are significantly reduced in human patients who go on to develop acute respiratory distress syndrome (ARDS) compared with healthy and non-ARDS intensive care unit (ICU) controls, as well as with other ICU patients without ARDS. Taken together, our findings identify a potentially novel adaptive response of the lung to stretch and a critical role for zinc in defining the lung's tolerance for mechanical ventilation. These results demonstrate that failure of stretch-adaptive responses play an important role in exacerbating mechanical ventilator-induced lung injury, and identify zinc and metallothionein as targets for lung-protective interventions in patients requiring mechanical ventilation.

17.
Crit Care Med ; 45(1): 58-68, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27632672

RESUMO

OBJECTIVE: To identify and measure recently described chemical mediators, termed specialized pro-resolving mediators that actively regulate the resolution of acute-inflammation, and correlate measurements with clinical outcomes. DESIGN: Herein, deidentified plasma was collected from sepsis patients (n = 22 subjects) within 48 hours of admission to the ICU and on days 3 and 7 thereafter and subjected to lipid mediator profiling. SETTING: Brigham and Women's Hospital Medical Intensive Care Unit. SUBJECTS: Patients in the medical ICU with sepsis. MEASUREMENTS AND MAIN RESULTS: In all patients, we identified more than 30 bioactive mediators and pathway markers in peripheral blood using established criteria for arachidonic acid, eicosapentaenoic acid, and docosahexaenoic acid metabolomes. These included inflammation initiating mediators leukotriene B4 and prostaglandin E2 and pro-resolving mediators resolvin D1, resolvin D2, and protectin D1. In sepsis nonsurvivors, we found significantly higher inflammation-initiating mediators including prostaglandin F2α and leukotriene B4 and pro-resolving mediators, including resolvin E1, resolvin D5, and 17R-protectin D1 than was observed in surviving sepsis subjects. This signature was present at ICU admission and persisted for 7 days. Further analysis revealed increased respiratory failure in nonsurvivors. Higher inflammation-initiating mediators (including prostaglandin F2α) and select proresolving pathways were associated with the development of acute respiratory distress syndrome, whereas other traditional clinical indices were not predictive of acute respiratory distress syndrome development. CONCLUSIONS: These results provide peripheral blood lipid mediator profiles in sepsis that correlate with survival and acute respiratory distress syndrome development, thus suggesting plausible novel biomarkers and biologic targets for critical illness.


Assuntos
Ácidos Docosa-Hexaenoicos/sangue , Eicosanoides/sangue , Insuficiência Respiratória/mortalidade , Sepse/sangue , Sepse/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Bicarbonatos/sangue , Bilirrubina/sangue , Gasometria , Citocinas/sangue , Análise Discriminante , Feminino , Escala de Coma de Glasgow , Humanos , Unidades de Terapia Intensiva , Masculino , Massachusetts/epidemiologia , Pessoa de Meia-Idade , Tempo de Tromboplastina Parcial , Respiração Artificial/estatística & dados numéricos , Síndrome do Desconforto Respiratório/sangue , Síndrome do Desconforto Respiratório/etiologia , Vasoconstritores/uso terapêutico
18.
Braz. J. Vet. Res. Anim. Sci. (Online) ; 54(2): 101-108, 2017. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-875071

RESUMO

Jatropha has been highlighted as an oleaginous potential for the production of biofuel. The cake, produced by oil extraction, could be used in animal feed. However, some varieties of jatropha are toxic by limiting their incorporation into animal diets. The objective of this study was to evaluate the hepatotoxicity of diets added with jatropha cake ­ JC (Jatropha curcas) in rats. Thirty-five (35) male Wistar adults rats (Rattus norvegicus) with initial weight of 352.1 ± 26.8 g were used. The animals were fed for 21 days with the diets: control, 10, 25, 40 and 50% JC. In the feeding with 50% JC the animals presented themselves prostrate and with piloerection. Development and survival decreased, since the inclusion of JC in diets increased. In rats submitted to 10 and 25% JC there was an increase of 17.52% in the hepatosomatic index in relation to the control group. Increase of JC in the rat diet promoted an increase in the activity of ALT and AST enzymes. Anatomic-histopathological evaluation demonstrated that, regardless of the levels tested, JC in rat diet causes hypertrophy of the hepatocytes, with a reduction in energy reserves. This study demonstrated that the use of JC resulted in decreased food intake, associated with weight loss due to the clinical pattern of toxicity, demonstrated by biochemical and histopathological changes in the liver. It was concluded that the inclusion of jatropha cake in rat feeding presents high hepatotoxic potential leading to lesions in the liver parenchyma.(AU)


O pinhão-manso tem se destacado como oleaginosa potencial para a produção de biocombustível. A torta, coproduto da extração do óleo, poderia ser utilizada na alimentação animal. No entanto, algumas variedades de pinhão-manso são tóxicas, limitando sua incorporação em dietas animais. Objetivou-se neste estudo avaliar a hepatotoxicidade de dietas acrescidas de torta de pinhão-manso (Jatropha curcas) em ratos. Foram utilizados trinta e cinco (35) ratos Wistar (Rattus norvergicus) machos adultos com peso inicial de 352,1 ± 26,8 g. Os animais foram alimentados por 21 dias com as dietas: controle, 10, 25, 40 e 50% TPM. Na alimentação com 50% TPM os animais apresentaram-se prostrados e com piloereção. O desenvolvimento e a sobrevivência apresentaram diminuição conforme o aumento da inclusão de TPM nas dietas. Em ratos submetidos a 10 e 25% TPM houve aumento de 17,52% no índice hepatossomático em relação ao grupo controle. O aumento de TPM na dieta de ratos promoveu aumento da atividade das enzimas ALT e AST. A avaliação anatomo-histopatológica revelou que, independentemente dos níveis testados, a TPM na alimentação de ratos provoca hipertrofia dos hepatócitos, com redução das reservas energéticas. Este estudo demonstrou que a utilização de TPM resultou em diminuição do consumo de alimento associado à perda de peso devido ao quadro clínico de toxicidade demonstrado pelas alterações bioquímica e histopatológica no fígado. Conclui-se que a inclusão de torta de pinhão-manso na alimentação de ratos apresenta alto potencial hepatotóxico levando a lesões no parênquima hepático.(AU)


Assuntos
Animais , Ratos , Ração Animal/análise , Ração Animal/toxicidade , Jatropha/toxicidade , Fígado/fisiopatologia , Ratos Wistar , Hepatócitos , Intoxicação por Plantas/veterinária
19.
Immunity ; 39(5): 885-98, 2013 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-24238341

RESUMO

The magnitude and duration of acute inflammation are controlled by active resolution programs involving specialized proresolving mediators (SPMs; resolvins and maresins) and microRNAs (miRNAs). Here, we report that miR-466l was temporally regulated in murine exudate-infiltrating leukocytes. Neutrophil miR-466l overexpression in vivo promoted initiation of inflammation that anteceded macrophage expression of this miRNA, which accelerated resolution when overexpressed. In macrophages, miR-466l overexpression increased prostanoids and SPMs (e.g., resolvin D1 [RvD1] and RvD5), which enhanced resolution. RvD1, RvD2, maresin 1 (MaR1), and apoptotic neutrophils reduced miR-466l expression within human macrophages, a feedback regulation that most likely prepares for homeostasis. miR-466l was upregulated in peripheral blood of sepsis patients, and its increase correlated with nonsurvival from sepsis. SPMs and miR-466l regulated transcription factors activator protein 1 and nuclear factor κB1 in miRNA biogenesis. These results demonstrate pivotal roles for SPMs and miR-466l in dynamic leukocyte plasticity during resolution of acute inflammatory responses.


Assuntos
Mediadores da Inflamação/metabolismo , Macrófagos/metabolismo , MicroRNAs/fisiologia , Neutrófilos/metabolismo , Peritonite/metabolismo , Sepse/sangue , Doença Aguda , Animais , Apoptose , Quimiotaxia/fisiologia , Ácidos Docosa-Hexaenoicos/metabolismo , Regulação da Expressão Gênica , Humanos , Masculino , Camundongos , MicroRNAs/biossíntese , MicroRNAs/genética , NF-kappa B/metabolismo , Peritonite/induzido quimicamente , Peritonite/imunologia , Peritonite/patologia , Fagocitose/fisiologia , Sepse/mortalidade , Fator de Transcrição AP-1/metabolismo , Transcrição Gênica , Zimosan/toxicidade
20.
PLoS Med ; 10(12): e1001577; discussion e1001577, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24391478

RESUMO

BACKGROUND: Mitochondrial DNA (mtDNA) is a critical activator of inflammation and the innate immune system. However, mtDNA level has not been tested for its role as a biomarker in the intensive care unit (ICU). We hypothesized that circulating cell-free mtDNA levels would be associated with mortality and improve risk prediction in ICU patients. METHODS AND FINDINGS: Analyses of mtDNA levels were performed on blood samples obtained from two prospective observational cohort studies of ICU patients (the Brigham and Women's Hospital Registry of Critical Illness [BWH RoCI, n = 200] and Molecular Epidemiology of Acute Respiratory Distress Syndrome [ME ARDS, n = 243]). mtDNA levels in plasma were assessed by measuring the copy number of the NADH dehydrogenase 1 gene using quantitative real-time PCR. Medical ICU patients with an elevated mtDNA level (≥3,200 copies/µl plasma) had increased odds of dying within 28 d of ICU admission in both the BWH RoCI (odds ratio [OR] 7.5, 95% CI 3.6-15.8, p = 1×10(-7)) and ME ARDS (OR 8.4, 95% CI 2.9-24.2, p = 9×10(-5)) cohorts, while no evidence for association was noted in non-medical ICU patients. The addition of an elevated mtDNA level improved the net reclassification index (NRI) of 28-d mortality among medical ICU patients when added to clinical models in both the BWH RoCI (NRI 79%, standard error 14%, p<1×10(-4)) and ME ARDS (NRI 55%, standard error 20%, p = 0.007) cohorts. In the BWH RoCI cohort, those with an elevated mtDNA level had an increased risk of death, even in analyses limited to patients with sepsis or acute respiratory distress syndrome. Study limitations include the lack of data elucidating the concise pathological roles of mtDNA in the patients, and the limited numbers of measurements for some of biomarkers. CONCLUSIONS: Increased mtDNA levels are associated with ICU mortality, and inclusion of mtDNA level improves risk prediction in medical ICU patients. Our data suggest that mtDNA could serve as a viable plasma biomarker in medical ICU patients.


Assuntos
Biomarcadores/sangue , DNA Mitocondrial/sangue , Mortalidade Hospitalar , Unidades de Terapia Intensiva/estatística & dados numéricos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
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