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2.
J Biomech ; 166: 112048, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38493577

RESUMO

Tendon xanthoma and altered mechanical properties have been demonstrated in people with familial hypercholesterolaemia. However, it is unclear whether mild, untreated hypercholesterolaemia alters musculotendinous mechanical properties and muscle architecture. We conducted a case-control study of adults aged 50 years and over, without lower limb injury or history of statin medication. Based on fasting low-density lipoprotein (LDL) cholesterol levels, 6 participants had borderline high LDL (>3.33 mmol/L) and 6 had optimal LDL cholesterol (<2.56 mmol/L). Using shear wave elastography, shear wave velocity (SWV) of the Achilles tendon and gastrocnemius medialis muscle (a proxy for stiffness), along with muscle fascicle length and pennation angle were measured under four passive tensile loads (0, 0.5, 1.0, 1.5 kg) applied via a pulley system. Differences between groups were found for tendon SWV but not muscle SWV, fascicle length or pennation angle. Participants with hypercholesterolaemia showed greater SWV (mean difference, 95 % CI: 2.4 m/s, 0.9 to 4.0, P = 0.024) compared to the control group across all loads. These findings suggest that adults with mild hypercholesterolaemia have increased tendon stiffness under low passive loads, while muscle was not affected. Future research is needed to confirm findings in a larger cohort and explore the impact of hypercholesterolaemia on tendon fatigue injury and tendinopathy.


Assuntos
Tendão do Calcâneo , Hipercolesterolemia , Traumatismos dos Tendões , Adulto , Humanos , Pessoa de Meia-Idade , Idoso , Tendão do Calcâneo/fisiologia , Estudos de Casos e Controles , Ultrassonografia , Músculo Esquelético/fisiologia
3.
Ultrasonography ; 43(3): 169-178, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38544459

RESUMO

Ultrasound shear wave elastography (SWE) is an emerging non-invasive imaging technique for peripheral nerve evaluation. Shear wave velocity (SWV), a surrogate measure of stiffness, holds promise as a biomarker for various peripheral nerve disorders. However, to maximize its clinical and biomechanical value, it is important to fully understand the factors that influence nerve SWV measurements. This systematic review aimed to identify the normal range of SWV for healthy sciatic and tibial nerves and to reveal the factors potentially affecting nerve SWV. An electronic search yielded 17 studies eligible for inclusion, involving 548 healthy individuals (age range, 17 to 72 years). Despite very good reliability metrics, the reported SWV values differed considerably across studies for the sciatic (1.9-9.9 m/s) and tibial (2.3-9.1 m/s) nerves. Factors such as measurement proximity to joint regions, limb postures inducing nerve axial stretching, and transducer alignment with nerve fiber orientation were associated with increased SWV. These findings suggest regional-specific nerve mechanical properties, non-linear elastic behaviour, and marked mechanical anisotropy. The impact of age and sex remains unclear and warrants further investigation. These results emphasize the importance of considering these factors when assessing and interpreting nerve SWE. While increased SWV has been linked to pathological changes affecting nerve tissue mechanics, the significant variability observed in healthy nerves highlights the need for standardized SWE assessment protocols. Developing guidelines for enhanced clinical utility and achieving a comprehensive understanding of the factors that influence nerve SWE assessments are critical in advancing the field.

4.
Phys Med Biol ; 69(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38262052

RESUMO

Objective.Skeletal muscles are organized into distinct layers and exhibit anisotropic characteristics across various scales. Assessing the arrangement of skeletal muscles may provide valuable biomarkers for diagnosing muscle-related pathologies and evaluating the efficacy of clinical interventions.Approach. In this study, we propose a novel ultrafast ultrasound sequence constituted of steered pushing beams was proposed for ultrasound elastography applications in transverse isotropic muscle. Based on the propagation of the shear wave vertical mode, it is possible to fit the experimental results to retrieve in the same imaging plane, the shear modulus parallel to fibers as well as the elastic anisotropy factor (ratio of Young's moduli times the shear modulus perpendicular to fibers).Main results. The technique was demonstratedin vitroin phantoms andex vivoin fusiform beef muscles. At last, the technique was appliedin vivoon fusiform muscles (biceps brachii) and mono-pennate muscles (gastrocnemius medialis) during stretching and contraction.Significance. This novel sequence provides access to new structural and mechanical biomarkers of muscle tissue, including the elastic anisotropy factor, within the same imaging plane. Additionally, it enables the investigation of multiples parameters during muscle active and passive length changes.


Assuntos
Técnicas de Imagem por Elasticidade , Músculo Esquelético , Animais , Bovinos , Anisotropia , Ultrassonografia , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiologia , Módulo de Elasticidade/fisiologia , Técnicas de Imagem por Elasticidade/métodos , Biomarcadores
5.
J Mech Behav Biomed Mater ; 150: 106325, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38150816

RESUMO

Acoustoelasticity theory describes propagation of shear waves in uniaxially stressed medium and allows the retrieval of nonlinear elastic coefficients of tissues. In transverse isotropic medium such as muscles the theory leads to 9 different configurations of propagating shear waves (stress axis vs. fibers axis vs. shear wave polarization axis vs. shear wave propagation axis). In this work we propose to use 4 configurations to quantify these nonlinear parameters ex vivo and in vivo. Ex vivo experiments combining ultrasound shear wave elastography and mechanical testing were conducted on iliopsoas pig muscles to quantify three third-order nonlinear coefficients A, H and K that are possibly linked to the architectural structure of muscles. In vivo experiments were performed with human volunteers on biceps brachii during a stretching exercise on an ergometer. A combination of the third order nonlinear elastic parameters was assessed. The knowledge of this nonlinear elastic parameters paves the way to quantify in vivo the local forces produced by muscle during exercise, contraction or movements.


Assuntos
Técnicas de Imagem por Elasticidade , Humanos , Animais , Suínos , Imagens de Fantasmas , Elasticidade , Ultrassonografia , Músculo Esquelético/diagnóstico por imagem
6.
Int J Phytoremediation ; : 1-11, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38059299

RESUMO

Soil contamination by toxic metals threatens global public health, highlighting the need for cost-effective and ecologically sound site remediation. In this study, we assessed phytoremediation of Hg-contaminated soils by Emilia fosbergii Nicolson (Asteraceae). Pot experiment was conducted using a substrate of sand and vermiculite (1:1 volume ratio), treatments consisted of five Hg concentrations (0, 1, 3, 5, and 7 mg kg-1). Metal transfer rates were calculated, including accumulation (BAF), translocation (TF) and bioconcentration (BCF) factors. E. fosbergii roots exhibited greater Hg accumulation than other tissues, but biomass production and plant health were not significantly affected at the concentrations tested, as indicated by elongation factors and tolerance index. The results revealed BAF values between 2.18 and 7.14, TF values ranged between 0.15 and 0.52, and the BCF index varied between 8.97 and 26.58. Treatments with Hg content of 5 mg kg-1 and 7 mg kg-1 recorded the highest total Hg concentrations of 66 mg kg-1 and 65.53 mg kg-1 (roots), and 9.18 mg kg-1 and 33.88 mg kg-1 (aerial), respectively. E. fosbergii demonstrated promise for Hg phytoremediation due to its high accumulation capacity, indicated by regular TF and high BCF and BAF indexes, thus classifying it as a high Hg accumulator.


Phytoextractor and phytostabilizer plant, high accumulator of Hg.Weed with great capacity for proliferation and adaptability.E. fosbergii showed tolerance to Hg in the substrate.Promising plant for phytoremediation of soils contaminated by Hg.Novel species for recovery of soils degraded by Hg exposure.

7.
Nanomaterials (Basel) ; 13(20)2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37887889

RESUMO

Nanofluids based on vegetal oil with different wt.% of carbon nanotubes (CNT), hexagonal boron nitride (h-BN), and its hybrid (h-BN@CNT) were produced to investigate the effects of these nano-additives on the thermal conductivity and rheological properties of nanofluids. Stable suspensions of these oil/nanostructures were produced without the use of stabilizing agents. The dispersed nanostructures were investigated by SEM, EDS, XRD, and XPS, while the thermal conductivity and rheological characteristics were studied by a transient hot-wire method and steady-state flow tests, respectively. Increases in thermal conductivity of up to 39% were observed for fluids produced with 0.5 wt.% of the hybrid nanomaterials. As for the rheological properties, it was verified that both the base fluid and the h-BN suspensions exhibited Newtonian behavior, while the presence of CNT modified this tendency. This change in behavior is attributed to the hydrophobic character of both CNT and the base oil, while h-BN nanostructures have lip-lip "bonds", giving it a partial ionic character. However, the combination of these nanostructures was fundamental for the synergistic effect on the increase of thermal conductivity with respect to their counterparts.

8.
PLoS One ; 18(7): e0289422, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37506126

RESUMO

BACKGROUND: It is widely acknowledged that eccentric muscle contractions may cause skeletal muscle damage. However, there is little knowledge about the impact of eccentric contractions on non-muscular structures. Animal and human studies revealed that eccentric contractions can also induce immediate and short-term nerve dysfunction. The purpose of this review is to examine whether eccentric muscle contractions induce immediate and short-term effects on structural, morphological, mechanical, functional and physiological properties of peripheral nerves, from both animal and human studies. METHODS AND ANALYSIS: A systematic review of randomised (RCTs) and non-randomised controlled trials will be conducted. Four electronic databases (i.e., Medline/Pubmed, Science Direct, PEDro and Cochrane) will be searched using predefined search terms to identify relevant studies. Eligible studies have to comprise any type of eccentric contraction of upper or lower limb muscles. Primary outcomes will include measures related to structure, morphology, mechanical, functional and physiological properties of peripheral nerves. Two independent reviewers will assess eligibility, evaluate risk of bias, and extract relevant data. In human studies, the risk of bias will be assessed by the Cochrane Collaboration risk of bias tool (RoB 2.0 tool) for RCTs and by risk of bias in non-randomised studies of interventions (ROBINS-I) for non-randomised controlled trials; while for animal studies, the risk of bias will be assessed using the SYRCLE's RoB tool. A narrative synthesis will be conducted for all included studies. Also, if appropriate, a meta-analysis will be performed, where the effect size of each outcome will be determined by the standardized mean difference as well as the 95% confidence intervals. I2 statistics will be used to assess heterogeneity. ETHICS AND DISSEMINATION: For this study, no ethical approval is required. Findings will be disseminated widely through peer-reviewed publication and conference presentations. SYSTEMATIC REVIEW REGISTRATION: The protocol has been registered at the International Prospective Register of Systematic Reviews (PROSPERO). Registration number: CRD42021285767.


Assuntos
Nervos Periféricos , Projetos de Pesquisa , Humanos , Viés , Metanálise como Assunto , Revisões Sistemáticas como Assunto
9.
Diabetologia ; 66(9): 1719-1734, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37301795

RESUMO

AIMS/HYPOTHESIS: Non-invasive in vivo corneal confocal microscopy is gaining ground as an alternative to skin punch biopsy to evaluate small-diameter nerve fibre characteristics. This study aimed to further explore corneal nerve fibre pathology in diabetic neuropathy. METHODS: This cross-sectional study quantified and compared corneal nerve morphology and microneuromas in participants without diabetes (n=27), participants with diabetes but without distal symmetrical polyneuropathy (DSPN; n=33), participants with non-painful DSPN (n=25) and participants with painful DSPN (n=18). Clinical and electrodiagnostic criteria were used to diagnose DSPN. ANCOVA was used to compare nerve fibre morphology in the central cornea and inferior whorl, and the number of corneal sub-epithelial microneuromas between groups. Fisher's exact tests were used to compare the type and presence of corneal sub-epithelial microneuromas and axonal swelling between groups. RESULTS: Various corneal nerve morphology metrics, such as corneal nerve fibre length and density, showed a progressive decline across the groups (p<0.001). In addition, axonal swelling was present more frequently (p=0.018) and in higher numbers (p=0.03) in participants with painful compared with non-painful DSPN. The frequency of axonal distension, a type of microneuroma, was increased in participants with painful and non-painful DSPN compared to participants with diabetes but without DSPN and participants without diabetes (all p≤0.042). The combined presence of all microneuromas and axonal swelling was increased in participants with painful DSPN compared with all other groups (p≤0.026). CONCLUSIONS/INTERPRETATION: Microneuromas and axonal swelling in the cornea increase in prevalence from participants with diabetes to participants with non-painful DSPN and participants with painful DSPN.


Assuntos
Diabetes Mellitus Tipo 2 , Neuropatias Diabéticas , Humanos , Estudos Transversais , Córnea/patologia , Dor , Pele/inervação , Microscopia Confocal , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/patologia
10.
Int J Biometeorol ; 67(7): 1273-1277, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37191730

RESUMO

Heat stress negatively affects livestock, with undesirable effects on animals' production and reproduction. Temperature and humidity index (THI) is a climatic variable used worldwide to study the effect of heat stress on farm animals. Temperature and humidity data can be obtained in Brazil through the National Institute of Meteorology (INMET), but complete data may not be available due to temporary failures on weather stations. An alternative to obtaining meteorological data is the National Aeronautics and Space Administration Prediction of Worldwide Energy Resources (NASA POWER) satellite-based weather system. We aimed to compare THI estimates obtained from INMET weather stations and NASA POWER meteorological information sources using Pearson correlation and linear regression. After quality check, data from 489 INMET weather stations were used. The hourly, average daily and maximum daily THI were evaluated. We found greater correlations and better regression evaluation metrics when average daily THI values were considered, followed by maximum daily THI, and hourly THI. NASA POWER satellite-based weather system is a suitable tool for obtaining the average and maximum THI values using information collected from Brazil, showing high correlations with THI estimates from INMET and good regression evaluation metrics, and can assist studies that aim to analyze the impact of heat stress on livestock production in Brazil, providing additional data to complement the existing information available in the INMET database.


Assuntos
Transtornos de Estresse por Calor , Meteorologia , Animais , Estados Unidos , Feminino , Umidade , Temperatura , Brasil , United States National Aeronautics and Space Administration , Tempo (Meteorologia) , Transtornos de Estresse por Calor/veterinária , Temperatura Alta , Lactação , Leite
11.
Environ Monit Assess ; 195(4): 477, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36928432

RESUMO

The spatial distribution and dispersion of mercury (Hg) is associated with the structural conditions of the environment, primarily land use and vegetation cover. Man-made emissions of the metal from activities such as artisanal and small-scale gold mining (ASGM) can influence this distribution. Forest ecosystems are of particular importance as they constitute one of the most active environments in the biogeochemical cycle of Hg, and understanding these dynamics is essential to better understand its global cycle. In this study, we determined the content of Hg present in different forest strata (soil, leaf litter, herbaceous, underwood/bush, and arboreal), as well as the relationship between the presence of Hg and the landscape heterogeneity, percentage of gold mines, and ground slope. This study was carried out in tropical forest areas of the southern Brazilian Amazon. Accumulation and transport of Hg between forest strata was assessed in order to understand the influence of these forest environments on Hg accumulation in areas where ASGM occurs. We verified that there is a difference in Hg content between forest strata, indicating that atmospheric Hg is accumulated onto the arboreal stratum and transported vertically to strata below the canopy, i.e., underwood/bush and herbaceous, and subsequently accumulated in the leaf litter and transferred to the soil. Leaf litter was the stratum with the highest Hg content, characterized as a receptor for most of the Hg load from the upper strata in the forest. Therefore, it was confirmed that Hg accumulation dynamics are at play between the areas analyzed due to the proximity of ASGMs in the region. This indicates that the conservation of forest areas plays an important role in the process of atmospheric Hg deposition and accumulation, acting as a mercury sink in areas close to man-made emissions.


Assuntos
Mercúrio , Humanos , Mercúrio/análise , Brasil , Ecossistema , Ouro/análise , Monitoramento Ambiental , Florestas , Árvores , Plantas , Mineração , Solo/química
12.
Sensors (Basel) ; 24(1)2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38203110

RESUMO

Lower limb exoskeletons and orthoses have been increasingly used to assist the user during gait rehabilitation through torque transmission and motor stability. However, the physical human-robot interface (HRi) has not been properly addressed. Current orthoses lead to spurious forces at the HRi that cause adverse effects and high abandonment rates. This study aims to assess and compare, in a holistic approach, human-robot joint misalignment and gait kinematics in three fixation designs of ankle-foot orthoses (AFOs). These are AFOs with a frontal shin guard (F-AFO), lateral shin guard (L-AFO), and the ankle modulus of the H2 exoskeleton (H2-AFO). An experimental protocol was implemented to assess misalignment, fixation displacement, pressure interactions, user-perceived comfort, and gait kinematics during walking with the three AFOs. The F-AFO showed reduced vertical misalignment (peak of 1.37 ± 0.90 cm, p-value < 0.05), interactions (median pressures of 0.39-3.12 kPa), and higher user-perceived comfort (p-value < 0.05) when compared to H2-AFO (peak misalignment of 2.95 ± 0.64 and pressures ranging from 3.19 to 19.78 kPa). F-AFO also improves the L-AFO in pressure (median pressures ranging from 8.64 to 10.83 kPa) and comfort (p-value < 0.05). All AFOs significantly modified hip joint angle regarding control gait (p-value < 0.01), while the H2-AFO also affected knee joint angle (p-value < 0.01) and gait spatiotemporal parameters (p-value < 0.05). Overall, findings indicate that an AFO with a frontal shin guard and a sports shoe is effective at reducing misalignment and pressure at the HRI, increasing comfort with slight changes in gait kinematics.


Assuntos
Órtoses do Pé , Robótica , Humanos , Fenômenos Biomecânicos , Tornozelo , Marcha
13.
Arq. ciências saúde UNIPAR ; 27(9): 5423-5436, 2023.
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1510776

RESUMO

OBJETIVO: analisar o perfil sociodemográfico e a tendência da mortalidade por infarto agudo miocárdio no Nordeste do Brasil entre os anos de 2011 a 2021. MÉTODOS: estudo ecológico que utilizou dados do Sistema de Informação sobre Mortalidade. Foram calculadas as taxas de mortalidade para o sexo dos indivíduos e estados da região nordestina. Para análise temporal foi utilizado o software Joinpoint. RESULTADOS: a maioria dos óbitos ocorreu entre homens (57,02%), pardos (60,81%) e idosos (76,22%). As médias da taxa de mortalidade foram elevadas nos homens acima dos 80 anos de idade (234,74 óbitos por 100 mil habitantes). Observou-se maiores tendências de aumento significativos de 3,8% e 3,2% ao ano da mortalidade por infarto em Alagoas e Bahia, respectivamente. CONCLUSÃO: entre os anos de 2011 a 2021 o infarto do miocárdio acometeu homens, idosos, da cor parda. Houve maior tendência de aumento nos estados de Alagoas e Bahia durante todo o período estudado. O estudo contribui para o direcionamento de políticas que identifique fatores de risco e elabore intervenções preventivas efetivas, investindo em diagnóstico precoce, programas de prevenção e promoção de saúde.


OBJECTIVE: to analyze the sociodemographic profile and temporal trend of acute myocardial infarction mortality in Northeast Brazil from 2011 to 2021. METHODS: this ecological study utilized data from the Mortality Information System. Mortality rates were calculated based on gender and states within the Northeast region. The Joinpoint software was used for temporal analysis. RESULTS: the majority of deaths occurred among males (57.02%), individuals of mixed race (60.81%), and elderly individuals (76.22%). The average mortality rate was highest among men above 80 years of age (234.74 deaths per 100,000 inhabitants). Significant increasing trends of 3.8% and 3.2% per year were observed for myocardial infarction mortality in Alagoas and Bahia, respectively. CONCLUSION: between 2011 and 2021, myocardial infarction predominantly affected elderly, male individuals of mixed race. Alagoas and Bahia showed the highest increasing trends in mortality throughout the study period. The study contributes to guiding policies that identify risk factors and develop effective preventive interventions, emphasizing early diagnosis, prevention programs, and health promotion. KEYWORDS: Myocardial Infarction; Mortality; Epidemiology; Time Series Studies.


OBJETIVO: Analizar el perfil sociodemográfico y la tendencia temporal de la mortalidad por infarto agudo de miocardio en el Noreste de Brasil entre los años 2011 y 2021. MÉTODOS: Este estudio ecológico utilizó datos del Sistema de Información sobre Mortalidad. Se calcularon tasas de mortalidad según el sexo de los individuos y los estados dentro de la región nordestina. Para el análisis temporal, se utilizó el software Joinpoint. RESULTADOS: La mayoría de los fallecimientos ocurrieron entre hombres (57,02%), individuos de raza mestiza (60,81%) y personas de edad avanzada (76,22%). La tasa media de mortalidad fue más alta en hombres mayores de 80 años (234,74 muertes por 100 mil habitantes). Se observaron tendencias significativamente crecientes del 3,8% y el 3,2% por año en la mortalidad por infarto en Alagoas y Bahía, respectivamente. CONCLUSIÓN: Entre 2011 y 2021, el infarto de miocardio afectó principalmente a hombres de edad avanzada, de raza mestiza. Alagoas y Bahía mostraron las tendencias crecientes más altas en mortalidad durante todo el período de estudio. El estudio contribuye a orientar políticas que identifiquen factores de riesgo y desarrollen intervenciones preventivas efectivas, haciendo hincapié en el diagnóstico temprano, programas de prevención y promoción de la salud.

14.
Med. clín. soc ; 6(2)ago. 2022.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1448603

RESUMO

Introducción: El acúfeno es un problema que afecta a una parte importante de la población, cuyas causas no están del todo claras. Actualmente no existe una cura ni consenso sobre el tratamiento de los acúfenos los cuales resultan ineficaces en muchos casos, se acompañan de efectos secundarios importantes o no proporcionan un alivio sintomatico a los pacientes. Se ha reportado que la inyección intratimpática de corticoesteroides mejora los síntomas. Objetivo: determinar el resultado de la infiltración transtimpánica de corticoides para el tratamiento de los acúfenos subjetivos. Metodología: El diseño es del estudio es observacional, descriptivo y correlacional, de muestreo fue no probabilístico de casos consecutivos. Se incluyó pacientes mayores de edad con acúfenos uni o bilateral de más de un mes de evolución como síntoma principal. Resultados: Se incluyó a 25 pacientes en la investigación, la mayor parte era del sexo masculino con una media de edades de aproximadamente 45 años. El principal tipo de pérdida auditiva asociado a estos pacientes fue la de tipo neurosensorial. No se encontraron diferencias audiométricas entre el pre y post infiltración. Conclusión: Un gran porcentaje de los pacientes presentaba alto grado de discapacidad por acúfenos y síntomas moderados a graves previo al tratamiento, posterior al mismo, este disminuyo, pero no de manera significativa.


Introduction: Tinnitus is a problem that affects an important part of the population, whose causes are not entirely clear. Currently there is no cure or consensus on the treatment of tinnitus, which is ineffective in many cases, is accompanied by significant side effects or does not provide symptomatic relief to patients. Intratympanic injection of corticosteroids has been reported to improve symptoms. Objective: to determine the result of transtympanic infiltration of corticosteroids for the treatment of subjective tinnitus. Methods: The design of the study is observational, descriptive and correlational, sampling was non-probabilistic of consecutive cases. Adult patients with unilateral or bilateral tinnitus of more than one month of evolution as the main symptom were included. Results: 25 patients were included in the research, most of them were male with a mean age of approximately 45 years. The main type of hearing loss associated with these patients was sensorineural. No audiometric differences were found between pre and post infiltration. Conclusion: A large percentage of patients had a high degree of disability due to tinnitus and moderate to severe symptoms prior to treatment, after which this decreased, but not significantly.

15.
Diabetes ; 71(8): 1785-1794, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35622081

RESUMO

In this cross-sectional study we aimed to quantify the somatosensory dysfunction in the hand in people with diabetes with distal symmetrical polyneuropathy (DSPN) in hands and explore early signs of nerve dysfunction in people with diabetes without DSPN in hands. The clinical diagnosis of DSPN was confirmed with electrodiagnosis and corneal confocal microscopy. Thermal and mechanical nerve function in the hand was assessed with quantitative sensory tests. Measurements were compared between healthy participants (n = 31), individuals with diabetes without DSPN (n = 35), individuals with DSPN in feet but not hands (DSPNFEET ONLY) (n = 31), and individuals with DSPN in hands and feet (DSPNHANDS & FEET) (n = 28) with one-way between-group ANOVA. The somatosensory profile of the hand in people with DSPNHANDS & FEET showed widespread loss of thermal and mechanical detection. This profile in hands is comparable with the profile in the feet of people with DSPN in feet. Remarkably, individuals with DSPNFEET ONLY already showed a similar profile of widespread loss of nerve function in their hands. People with diabetes without DSPN in feet already had some nerve dysfunction in their hands. These findings suggest that nerve function assessment in hands should become more routine in people with diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Neuropatias Diabéticas , Polineuropatias , Córnea , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Neuropatias Diabéticas/diagnóstico , Neuropatias Diabéticas/epidemiologia , Humanos , Microscopia Confocal
16.
Parasitol Int ; 89: 102584, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35413437

RESUMO

This study aimed to determine whether live vaccines alone or associated with phytogenic compounds supplied via feed could improve performance, intestinal health, serum biochemistry, and coccidiostatic action in broilers up to 42 days of age, challenged with Eimeria spp., compared with a traditional anticoccidial program. We used 800 birds divided into five treatments of eight repetitions each (n = 20): NC - Negative control (absence of additives in the feed and without coccidian challenge); PC - Positive control (absence of additives and with coccidian challenge at 21 days); AAP - Anticoccidial additives program, including salinomycin and nicarbazine, with coccidian challenge at 21 days of life; VAC - Vaccination on day 1 of life (Hipracox HIPRA®) against coccidiosis and subsequent coccidian challenge at 21 days; VAC + BPC - Vaccination (day 1 of life), the addition of 200 ppm of blend phytogenic compound (BPC) based on carvacrol and cinnamaldehyde to the diet, with coccidian challenge at 21 days of life. The birds in the AAP group more significant weight gain and greater body weight at 21 days than the NC and 42 days of age than the NC and VAC + BPC groups. The excretion of Eimeria oocysts in the excreta of birds was higher in PC than in NC, and in the litter, PC had higher counts than NC, AAP, and VAC + BPC. A higher mean score of intestinal lesions for Eimeria acervulina was observed in VAC and VAC + BPC birds, while for Eimeria maxima, the highest score was found in PC. Higher serum levels of total protein due to the increase in globulins were observed in birds of AAP and VAC than NC. Our findings suggest that vaccination for coccidiosis shortly after the birth of chicks allows performance similar to the conventional coccidiosis control program via diet.


Assuntos
Coccidiose , Eimeria , Doenças das Aves Domésticas , Ração Animal/análise , Animais , Galinhas , Coccidiose/prevenção & controle , Coccidiose/veterinária , Dieta/veterinária , Suplementos Nutricionais , Doenças das Aves Domésticas/prevenção & controle , Vacinas Atenuadas
17.
J Biomech ; 136: 111075, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35390647

RESUMO

Ultrasound shear wave elastography has become a promising method in peripheral neuropathy evaluation. Shear wave velocity, a surrogate measure of stiffness, tends to increase in peripheral neuropathies regardless of etiology. However, little is known about the spatial variation in shear wave velocity of healthy peripheral nerves and how tensile loading is distributed along their course. Sixty healthy young adults were scanned using ultrasound shear wave elastography. Five regions of the sciatic (SciaticPROXIMAL, SciaticDISTAL) and tibial nerve (TibialPROXIMAL, TibialINTERMEDIATE, and TibialDISTAL) were assessed in two hip positions that alter nerve tension: 1) neutral in supine position; and 2) flexed at 90°. Knee and ankle remained in full-extension and neutral position. We observed spatial variations in shear wave velocity along the sciatic and tibial nerve (P < 0.0001). Shear wave velocities were significantly different between all nerve locations with the exception of SciaticDISTAL vs. TibialINTERMEDIATE (P = 0.999) and TibialPROXIMAL vs. TibialINTERMEDIATE (P = 0.708), and tended to increase in the proximal-distal direction at both upper and lower leg segments. Shear wave velocity increased with hip flexion (+54.3%; P < 0.0001), but the increase was not different among nerve locations (P = 0.233). This suggests that the increase in tensile loading with hip flexion is uniformally distributed along the nerve tract. These results highlight the importance of considering both limb position and transducer location for biomechanical and clinical assessments of peripheral nerve stiffness. These findings provide evidence about how tension is distributed along the course of sciatic and tibial nerves.


Assuntos
Técnicas de Imagem por Elasticidade , Doenças do Sistema Nervoso Periférico , Articulação do Tornozelo , Técnicas de Imagem por Elasticidade/métodos , Humanos , Nervo Tibial/diagnóstico por imagem , Ultrassonografia , Adulto Jovem
18.
Front Genet ; 13: 815476, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35281848

RESUMO

Motivation: The increasing availability of metabolomic data and their analysis are improving the understanding of cellular mechanisms and how biological systems respond to different perturbations. Currently, there is a need for novel computational methods that facilitate the analysis and integration of increasing volume of available data. Results: In this paper, we present Totoro a new constraint-based approach that integrates quantitative non-targeted metabolomic data of two different metabolic states into genome-wide metabolic models and predicts reactions that were most likely active during the transient state. We applied Totoro to real data of three different growth experiments (pulses of glucose, pyruvate, succinate) from Escherichia coli and we were able to predict known active pathways and gather new insights on the different metabolisms related to each substrate. We used both the E. coli core and the iJO1366 models to demonstrate that our approach is applicable to both smaller and larger networks. Availability: Totoro is an open source method (available at https://gitlab.inria.fr/erable/totoro) suitable for any organism with an available metabolic model. It is implemented in C++ and depends on IBM CPLEX which is freely available for academic purposes.

19.
J Man Manip Ther ; 30(1): 3-12, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34781843

RESUMO

Tensioning techniqueswere the first neurodynamic techniques used therapeutically in the management of people with neuropathies. This article aims to provide a balanced evidence-informed view on the effects of optimal tensile loading on peripheral nerves and the use of tensioning techniques. Whilst the early use of neurodynamics was centered within a mechanical paradigm, research into the working mechanisms of tensioning techniques revealed neuroimmune, neurophysiological, and neurochemical effects. In-vitro and ex-vivo research confirms that tensile loading is required for mechanical adaptation of healthy and healing neurons and nerves. Moreover, elimination of tensile load can have detrimental effects on the nervous system. Beneficial effects of tensile loading and tensioning techniques, contributing to restored homeostasis at the entrapment site, dorsal root ganglia and spinal cord, include neuronal cell differentiation, neurite outgrowth and orientation, increased endogenous opioid receptors, reduced fibrosis and intraneural scar formation, improved nerve regeneration and remyelination, increased muscle power and locomotion, less mechanical and thermal hyperalgesia and allodynia, and improved conditioned pain modulation. However, animal and cellular models also show that 'excessive' tensile forces have negative effects on the nervous system. Although robust and designed to withstand mechanical load, the nervous system is equally a delicate system. Mechanical loads that can be easily handled by a healthy nervous system, may be sufficient to aggravate clinical symptoms in patients. This paper aims to contribute to a more balanced view regarding the use of neurodynamics and more specifically tensioning techniques.


Assuntos
Gânglios Espinais , Doenças do Sistema Nervoso Periférico , Animais , Humanos , Hiperalgesia/terapia , Neurônios , Medula Espinal
20.
Coluna/Columna ; 20(3): 181-184, July-Sept. 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1339752

RESUMO

ABSTRACT Objective To estimate the amount of radiation received and accumulated in the bodies of two surgeons, one being the responsible surgeon and the other the assistant, performing spine surgery procedures over a period of 25 years. Methods Seventy-two spinal surgeries were performed during a seven-month period and the radiation loads were measured in both surgeons. The measurement of radiation was captured in fluoroscopy in anteroposterior and lateral incidences. The surgeon and the assistant used two dosimeters, one in the cervical region protecting the thyroid and the other on the lead apron in the genital region. The radioactive loads were measured in millisieverts and the accumulated charges were recorded monthly in both regions of the body in the two surgeons for seven months and the means for the work periods (1, 5, 10, 15, 20 and 25 years) were estimated. Results It was observed that in the surgeon the average accumulated radiation loads were 131.9% and 176.92% higher than those of the assistant in the cervical and genital regions, respectively. Conclusion While the use of X-rays is indispensable in routine orthopedic surgery, we have to consider the development of techniques of protection, rigor and discipline in the use of safety materials for surgeons. Preventive exposure reduction measures such as using thyroid protection equipment and turning the head away from the patient during fluoroscopy, among others, should be mandatory to promote less radiation exposure. Level of evidence II; Comparative prospective study.


RESUMO Objetivo Estimar a quantidade de radiação recebida e acumulada no corpo de dois cirurgiões, durante período de 25 anos de trabalho, sendo um o cirurgião responsável e outro, assistente, nos procedimentos de cirurgia da coluna vertebral. Métodos Foram realizadas 72 cirurgias de coluna vertebral em um período de sete meses, e as cargas de radiação foram medidas nos dois cirurgiões. A medição da radiação foi captada em fluoroscópio nas incidências anteroposterior e de perfil. O cirurgião e o auxiliar utilizaram dois dosímetros, sendo um na região cervical protegendo a tireoide e outro sobre o avental de chumbo, na região genital. As cargas radioativas foram medidas em milisievert e as cargas acumuladas foram registradas mensalmente em ambas as regiões do corpo nos dois cirurgiões, durante sete meses, foram estimadas as médias no período (1, 5, 10, 15, 20 e 25 anos) de trabalho. Resultados Observou-se que no cirurgião as médias das cargas de radiação acumulada foram 131,9% e 176,92% superiores às do assistente nas regiões cervical e genital, respectivamente. Conclusão Enquanto o uso dos raios X for indispensável na rotina da cirurgia ortopédica, há de se considerar o desenvolvimento de técnicas de proteção, rigor e disciplina no uso materiais de segurança para os cirurgiões. Medidas preventivas de redução da exposição, como uso de equipamento para proteção da tireoide e girar a cabeça para se afastar do paciente durante a fluoroscopia, entre outras, devem ser obrigatórias para promover menor exposição à radiação. Nível de evidência II; Estudo prospectivo comparativo.


RESUMEN Objetivo Estimar la cantidad de radiación recibida y acumulada en el cuerpo de dos cirujanos, durante 25 años de trabajo, siendo uno el cirujano responsable y el otro, asistente, en los procedimientos de cirugía de columna vertebral. Métodos Se realizaron 72 cirugías de columna vertebral en un período de siete meses, y las cargas de radiación fueron medidas en los dos cirujanos. La medición de la radiación fue captada en fluoroscopio en las incidencias anteroposterior y de perfil. El cirujano y el auxiliar usaron dos dosímetros, siendo uno en la región cervical protegiendo la tiroides y otro sobre el delantal de plomo, en la región genital. Las cargas radiactivas se midieron en milisievert, y las cargas acumuladas se registraron mensualmente en ambas regiones del cuerpo, en los dos cirujanos, durante siete meses, y se estimaron los promedios durante el período (1, 5, 10, 15, 20 y 25 años) de trabajo. Resultados Se observó que en el cirujano los promedios de las cargas de radiación acumulada fueron de 131,9% y 176,92% superiores a las del asistente en las regiones cervical y genital, respectivamente. Conclusión Mientras el uso de rayos X sea indispensable en la rutina de la cirugía ortopédica, hay que considerar el desarrollo de técnicas de protección, rigor y disciplina en el uso de materiales de seguridad para los cirujanos. Las medidas preventivas de reducción de la exposición, como uso de equipamiento para protección de la tiroides y girar la cabeza para alejarse del paciente durante la fluoroscopia, entre otras, deben ser obligatorias para promover menor exposición a la radiación. Nivel de evidencia II; Estudio prospectivo comparativo.


Assuntos
Humanos , Coluna Vertebral/cirurgia , Exposição à Radiação/estatística & dados numéricos , Equipamento de Proteção Individual , Cirurgiões Ortopédicos/estatística & dados numéricos , Fatores de Tempo
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