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1.
Haematologica ; 105(5): 1443-1453, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31371418

RESUMO

Pharmacokinetic-based prophylaxis of replacement factor VIII (FVIII) products has been encouraged in recent years, but the relationship between exposure (factor VIII activity) and response (bleeding frequency) remains unclear. The aim of this study was to characterize the relationship between FVIII dose, plasma FVIII activity, and bleeding patterns and individual characteristics in severe hemophilia A patients. Pooled pharmacokinetic and bleeding data during prophylactic treatment with BAY 81-8973 (octocog alfa) were obtained from the three LEOPOLD trials. The population pharmacokinetics of FVIII activity and longitudinal bleeding frequency, as well as bleeding severity, were described using non-linear mixed effects modeling in NONMEM. In total, 183 patients [median age 22 years (range, 1-61); weight 60 kg (11-124)] contributed with 1,535 plasma FVIII activity observations, 633 bleeds and 11 patient/study characteristics [median observation period 12 months (3.1-13.1)]. A parametric repeated time-to-categorical bleed model, guided by plasma FVIII activity from a 2-compartment population pharmacokinetic model, described the time to the occurrence of bleeds and their severity. Bleeding probability decreased with time of study, and a bleed was not found to affect the time of the next bleed. Several covariate effects were identified, including the bleeding history in the 12-month pre-study period increasing the bleeding hazard. However, unexplained inter-patient variability in the phenotypic bleeding pattern remained large (111%CV). Further studies to translate the model into a tool for dose individualization that considers the individual bleeding risk are required. Research was based on a post-hoc analysis of the LEOPOLD studies registered at clinicaltrials.gov identifiers: 01029340, 01233258 and 01311648.


Assuntos
Hemofilia A , Adolescente , Adulto , Testes de Coagulação Sanguínea , Peso Corporal , Criança , Pré-Escolar , Fator VIII , Hemofilia A/tratamento farmacológico , Hemorragia/epidemiologia , Hemorragia/etiologia , Humanos , Lactente , Pessoa de Meia-Idade , Adulto Jovem
2.
Somatosens Mot Res ; 37(2): 125-131, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32314675

RESUMO

Objective: The way how individual bars of sensorimotor insoles influence the gait kinematics is not fully understood yet. Therefore, this study aimed to explore the effect of three sensorimotor orthotic conditions (the medial calcaneal and retrocapital lateral bars and their combination) on the gait parameters in healthy adults during the stance phase of gait cycle.Materials and methods: Twenty-six young adults performed 20 gait cycles in each condition using their self-selected cadence and provided standardised shoes with the base-sole and the three types of orthotics. A three-dimensional motion analysis system (8 cameras; 200 Hz) was used and a six-degrees of freedom model was applied. The cadence, the stride length, the first peaks of foot external rotation, eversion and dorsal flexion as well as the first peak of hip adduction were analysed.Results: Significant differences (p < 0.05) were found for all parameters between the orthotic conditions, except the cadence. Significant difference in the first peak of hip adduction (p = 0.008) was found between the dominant and non-dominant leg. There were no significant interactions between the factors of condition and leg dominance (p > 0.05).Conclusions: There seems to be overall tendencies in immediate changes in ankle joint kinematics caused by all three sensorimotor orthotic conditions and besides the mechanical principles, also 'proprioceptive mechanism' seems to play a role. However, maximum observed average angular change was 2° and some variability in reactions to each orthotic condition exists among the individuals. Therefore, clinical relevance of such changes remains unclear and careful analysis of expected outcomes should be the common part of every orthotic intervention.


Assuntos
Marcha , Sapatos , Adulto Jovem , Humanos , , Aparelhos Ortopédicos , Articulação do Tornozelo , Fenômenos Biomecânicos
3.
Br J Clin Pharmacol ; 85(6): 1326-1336, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30767254

RESUMO

AIMS: This study aims to assess approaches to handle interoccasion variability (IOV) in a model-based therapeutic drug monitoring (TDM) context, using a population pharmacokinetic model of coagulation factor VIII as example. METHODS: We assessed 5 model-based TDM approaches: empirical Bayes estimates (EBEs) from a model including IOV, with individualized doses calculated based on individual parameters either (i) including or (ii) excluding variability related to IOV; and EBEs from a model excluding IOV by (iii) setting IOV to zero, (iv) summing variances of interindividual variability (IIV) and IOV into a single IIV term, or (v) re-estimating the model without IOV. The impact of varying IOV magnitudes (0-50%) and number of occasions/observations was explored. The approaches were compared with conventional weight-based dosing. Predictive performance was assessed with the prediction error percentiles. RESULTS: When IOV was lower than IIV, the accuracy was good for all approaches (50th percentile of the prediction error [P50] <7.4%), but the precision varied substantially between IOV magnitudes (P97.5 61-528%). Approach (ii) was the most precise forecasting method across a wide range of scenarios, particularly in case of sparse sampling or high magnitudes of IOV. Weight-based dosing led to less precise predictions than the model-based TDM approaches in most scenarios. CONCLUSIONS: Based on the studied scenarios and theoretical expectations, the best approach to handle IOV in model-based dose individualization is to include IOV in the generation of the EBEs but exclude the portion of unexplained variability related to IOV in the individual parameters used to calculate the future dose.


Assuntos
Coagulantes/administração & dosagem , Coagulantes/farmacocinética , Cálculos da Dosagem de Medicamento , Monitoramento de Medicamentos , Fator VIII/administração & dosagem , Fator VIII/farmacocinética , Hemofilia A/tratamento farmacológico , Modelos Biológicos , Adolescente , Adulto , Idoso , Criança , Coagulantes/efeitos adversos , Simulação por Computador , Fator VIII/efeitos adversos , Hemofilia A/sangue , Hemofilia A/diagnóstico , Hemostasia/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
4.
J Vasc Interv Radiol ; 29(6): 841-849, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29724521

RESUMO

PURPOSE: To evaluate the efficacy and safety of transarterial chemoembolization with polyethylene glycol (PEG) drug-eluting embolic agents in the treatment of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: A single-center retrospective study of 302 patients (258 men; 85.4%) with HCC treated during a 20-month period was conducted. The mean patient age was 66 years ± 10; 142 (47%) had Barcelona Clinic Liver Cancer stage A disease and 134 had (44.4%) stage B disease; 174 (57.6%) had a single HCC tumor, 65 (21.5%) had 2, and 62 (20.9%) had 3 or more. Mean index tumor size was 36.6 mm ± 24.8. One-month follow-up computed tomography (CT) response per modified Response Evaluation Criteria In Solid Tumors and clinical and biochemical safety were analyzed. Progression-free and overall survival were calculated by Kaplan-Meier method. RESULTS: Median follow-up time was 11.9 months (95% confidence interval, 11.0-13.0 mo). One-month follow-up CT revealed complete response in 179 patients (63.2%), partial response in 63 (22.3%), stable disease in 16 (5.7%), and progressive disease in 25 (8.8%). The most frequent complications were postembolization syndrome in 18 patients (6%), liver abscess in 5 (1.7%), and puncture-site hematoma in 3 (1%). Biochemical toxicities occurred in 57 patients (11.6%). Survival analysis at 12 months showed a progression-free survival rate of 65.9% and overall survival rate of 93.5%. Patients who received transplants showed a 57.7% rate of complete pathologic response. CONCLUSIONS: Chemoembolization with PEG embolic agents for HCC is safe and effective, achieving an objective response rate of 85.5%.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/terapia , Polietilenoglicóis/administração & dosagem , Idoso , Meios de Contraste , Progressão da Doença , Feminino , Humanos , Masculino , Radiografia Intervencionista , Estudos Retrospectivos , Taxa de Sobrevida , Tomografia Computadorizada por Raios X , Resultado do Tratamento
5.
Somatosens Mot Res ; 35(3-4): 170-177, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30299193

RESUMO

OBJECTIVE: This study aimed to investigate the foot contact time differences between obese and non-obese subjects during walking when crossing obstacles. METHODS: Ninety-eight postmenopausal women were assigned to four groups, and their plantar pressure temporal data were collected using a two-step protocol during walking when crossing an obstacle set at 30% height of lower limb length of each subject. The initial, final, and duration of contact of 10 foot areas were measured. RESULTS: Leading limb: (1) the heel groups initiated foot contact using the heel, and the non-heel groups initiated contact using the metatarsals; (2) heel obese subjects showed an earlier initial contact and a longer contact duration of metatarsals 2-3; (3) non-heel obese subjects showed an earlier midfoot initial contact. Regarding the trailing limb: (4) heel obese subjects showed an earlier midfoot initial contact and a longer contact duration of metatarsal 5; (5) non-heel obese subjects showed an earlier initial contact and a longer contact duration of metatarsals 4-5. CONCLUSIONS: (1) The non-heel groups' foot rollover pattern may result from an attempt of rapidly restoring stability; (2) the heel obese subjects seem to regulate their plantar foot muscles to overcome their overweight; (3) the overweight of the non-heel obese subjects leads to a quicker backward foot roll-over from the metatarsals to the heel; (4) the overweight of the heel obese subjects can distort their footprints and/or their higher inertia may precipitate an anticipation of the midfoot contact, which can also explain the result observed for 5.


Assuntos
Pé/inervação , Obesidade/fisiopatologia , Pós-Menopausa , Desempenho Psicomotor/fisiologia , Adulto , Idoso , Fenômenos Biomecânicos , Feminino , Humanos , Pessoa de Meia-Idade , Pressão , Fatores de Tempo , Caminhada
6.
J Aging Phys Act ; 26(2): 227-234, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28714798

RESUMO

The aim of this study was to compare the temporal foot rollover data between walking straight ahead and stepping over obstacles for obese and non-obese postmenopausal women. Plantar pressure data were collected from 67 women. The initial, final, and duration of contact of 10 foot areas were measured. Both limbs of both groups showed a longer foot contact duration on the obstacle task. Significant temporal differences were found for both groups between straight ahead and crossing obstacles on the initial, final, and duration of contact for several foot areas. The propulsion phase of the trailing limb during the obstacle task was anticipated. Regarding the leading limb, the first foot contact was not made with the heel areas; however, a backward foot rollover movement from the metatarsal to the heel areas occurred, possibly to provide support to better control the trailing limb swing phase.


Assuntos
, Marcha , Obesidade/fisiopatologia , Caminhada , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa
7.
J Strength Cond Res ; 32(1): 217-222, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29257796

RESUMO

Psurny, M, Svoboda, Z, Janura, M, Kubonova, E, Bizovska, L, Martinez Lemos, RI, and Abrantes, J. The effects of Nordic walking and slope of the ground on lower limb muscle activity. J Strength Cond Res 32(1): 217-222, 2018-Nordic walking (NW) has proven to be a simple and safe mode of exercise that can be used in various types of sport, recreation, and rehabilitation activities. The aim of this study was to assess the effect of Nordic walking and slope of the ground on lower limb muscle activity. The experimental group consisted of 22 healthy men (aged 22.8 ± 1.4 years). The subjects walked on a treadmill at a self-selected speed. Two walking conditions (NW and walking) and 2 ground slopes (level ground and uphill walking at an 8% incline) were used. The surface electromyographic signals of the gastrocnemius lateralis, tibialis anterior, vastus medialis, rectus femoris, biceps femoris and gluteus medius were recorded. Nordic walking resulted in increased activity of some lower limb muscles, particularly during the first half of the stance phase, and decreased muscle activity during the first half of the swing phase. Uphill walking elicited increased muscle activity compared with level walking, particularly during the stance phase and the second half of the swing phase during both walking and NW, and the change was more pronounced during walking. We concluded that NW increased muscle activity in the lower extremities compared with walking, particularly on level ground. Increasing the ground slope enhanced the muscle activity to a much greater extent than NW.


Assuntos
Extremidade Inferior/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Caminhada/fisiologia , Adulto , Fenômenos Biomecânicos , Estudos Transversais , Eletromiografia , Teste de Esforço , Marcha/fisiologia , Humanos , Masculino , Músculo Quadríceps/fisiologia , Adulto Jovem
8.
Eur J Clin Pharmacol ; 72(4): 459-67, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26762381

RESUMO

PURPOSE: Transdermal fentanyl is effective for the treatment of moderate to severe cancer-related pain but is unsuitable for fast titration. In this setting, continuous subcutaneous fentanyl may be used. As data on the pharmacokinetics of continuous subcutaneous fentanyl are lacking, we studied the pharmacokinetics of subcutaneous and transdermal fentanyl. Furthermore, we evaluated rotations from the subcutaneous to the transdermal route. METHODS: Fifty-two patients treated with subcutaneous and/or transdermal fentanyl for moderate to severe cancer-related pain participated. A population pharmacokinetic model was developed and evaluated using non-linear mixed-effects modelling. For rotations from subcutaneous to transdermal fentanyl, a 1:1 dose conversion ratio was used while the subcutaneous infusion was continued for 12 h (with a 50 % tapering after 6 h). A 6-h scheme with 50 % tapering after 3 h was simulated using the final model. RESULTS: A one-compartment model with first-order elimination and separate first-order absorption processes for each route adequately described the data. The estimated apparent clearance of fentanyl was 49.6 L/h; the absorption rate constant for subcutaneous and transdermal fentanyl was 0.0358 and 0.0135 h(-1), respectively. Moderate to large inter-individual and inter-occasion variability was found. Around rotation from subcutaneous to transdermal fentanyl, measured and simulated plasma fentanyl concentrations rose and increasing side effects were observed. CONCLUSIONS: We describe the pharmacokinetics of subcutaneous and transdermal fentanyl in one patient cohort and report several findings that are relevant for clinical practice. Further research is warranted to study the optimal scheme for rotations from the subcutaneous to the transdermal route.


Assuntos
Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/farmacocinética , Dor do Câncer/tratamento farmacológico , Dor do Câncer/etiologia , Fentanila/administração & dosagem , Fentanila/farmacocinética , Neoplasias/complicações , Administração Cutânea , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Infusões Intravenosas/métodos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
ScientificWorldJournal ; 2014: 845460, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25371915

RESUMO

Macropores and water flow in soils and substrates are complex and are related to topics like preferential flow, nonequilibrium flow, and dual-continuum. Hence, the quantification of the number of macropores and the determination of their geometry are expected to provide a better understanding on the effects of pores on the soil's physical and hydraulic properties. This exploratory study aimed at evaluating the potential of using infrared thermography for mapping macroporosity at the soil surface and estimating the number and size of such macropores. The presented technique was applied to a small scale study (laboratory soil flume).


Assuntos
Solo/química , Termografia/métodos , Laboratórios , Porosidade , Projetos de Pesquisa , Propriedades de Superfície , Água/metabolismo
10.
Healthcare (Basel) ; 12(2)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38255074

RESUMO

Falls are a major concern in the elderly and walking is an important daily activity in which falls occur, with tripping and slipping being the most frequent causes. Gait biomechanical parameters have been related to the occurrence of falls in the elderly. Moreover, there is evidence that falls can be prevented through exercise programs, which have been shown to be also effective in improving gait biomechanical parameters. However, a question remains: "What types of exercises must be included in exercise programs to prevent falls?". The purpose of this manuscript was to present guidelines for a fall prevention exercise program for the elderly, which was created with the aim of improving the gait biomechanical parameters related to falls. The critical review performed during the preparation of this manuscript collected important evidence and knowledge in order to create a structural basis for the development of a fall prevention exercise program. This type of program should last 6 or more weeks and be prescribed based on four movement pillars (locomotion, level changes, pulling and pushing, and rotations); however, the locomotion pillar must be the focus of the program. Proprioceptive and functional strength exercises should be included in this program. Based on the theoretical rationale, a proposal for a fall prevention exercise program is presented.

11.
J Bodyw Mov Ther ; 38: 197-204, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38763563

RESUMO

BACKGROUND: Functional Movement Screen (FMS) is an important tool in the assessment of exercise practice. Assuming FMS lacks precise validity for assessing postural deficits, further research is needed to assess whether it is a sufficiently precise tool for analysing joint mobility. Research aims were to evaluate: convergent validity of Deep Squat (DS) - one of FMS tests - regarding joint mobility, using data from a three-dimensional motion analysis as a comparable method; DS's ability to discriminate between subjects with different joint mobility levels. METHODS: Sixty subjects were selected (23.6 ± 3.8 years). DS was performed according to FMS guidelines. Subjects' performance in frontal and sagittal planes was recorded by two video cameras and subsequently scored by two FMS-certified evaluators. Three-dimensional motion analyses of DS were acquired by a Vicon Motion Capture System (200 Hz). Ten trials were acquired for each subject. Ankle, knee, hip, and shoulder angular positions in sagittal plane were determined from the FullBody PlugInGait model. Spearman's coefficient examined the correlation between angular positions and DS score. Kruskal-Wallis test was used to assess the DS ability to discriminate between subjects with different joint mobility levels by comparing different scores. RESULTS: Negligible to moderate correlations were found between DS score and angular positions (-0.5 < r < 0.5). Only shoulder angular positions showed differences between score "1" and "2" (p < 0.05). Shoulder and hip angular positions showed no differences between score "2" and "3" (p < 0.05). CONCLUSIONS: DS yielded low convergent validity regarding joint mobility and did not show the ability to discriminate between subjects with different joint mobility levels.


Assuntos
Amplitude de Movimento Articular , Humanos , Masculino , Feminino , Adulto , Amplitude de Movimento Articular/fisiologia , Adulto Jovem , Reprodutibilidade dos Testes , Teste de Esforço/métodos , Teste de Esforço/normas , Articulação do Tornozelo/fisiologia , Articulação do Joelho/fisiologia , Fenômenos Biomecânicos/fisiologia , Articulação do Quadril/fisiologia , Movimento/fisiologia , Articulação do Ombro/fisiologia , Articulação do Ombro/fisiopatologia
12.
Curr Aging Sci ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38779738

RESUMO

INTRODUCTION AND OBJECTIVE: There is limited research on the changes that can occur in the gait biomechanical parameters of older adults over long-distance walking. Thus, this study aimed to evaluate the gait characteristics of older women of a specific Portuguese community over the six-minute walk test (6MWT) along with gait spatial and temporal parameters and angular kinematics of the lower limb joints. MATERIALS AND METHODS: Twenty-six older women voluntarily participated. Each woman performed the 6MWT, and during this, their spatial and temporal parameters were collected through plantar pressure data (100Hz) and angular kinematics through an inertial sensor system (100Hz). The 6MWT was divided into four intervals, and the Friedman test was used to compare them. The median age of the women was calculated, and the Mann-Whitney test was used to compare women above and below the median age value. RESULTS: An increase in gait speed, stance phase, and double stance phase along the intervals was observed, as well as larger angular displacements of the hip, knee, and ankle (p<0.05). Women below or above the median age value also yielded these behaviours. Gait speed, cadence, stride length, and step length were higher in women below the median age value, while stride and step duration were lower (p<0.05). CONCLUSION: Older women yielded changes in gait spatial and temporal parameters along the 6MWT, as well as larger angular displacements of the lower limb joints. Older women (compared to younger ones) yielded lower gait speed, cadence, stride length, and step length, higher stance and double stance phases, and shorter angular displacements of the lower limb joints.

13.
J Sports Sci ; 31(14): 1559-67, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23672576

RESUMO

We investigated the mechanical properties of the triceps surae between professional, junior, and non-football players. Fifty-nine men participated in this study. The mechanical properties of the right legs' triceps surae were measured in vivo using a free oscillation technique; no significant differences existed between the groups. The mean results for musculo-articular stiffness, damping coefficient, and damping ratio were as follows: professional football players (21523 N· m⁻¹, 330.8 N · s · m⁻¹, and 0.201); junior football players (21063 N · m⁻¹, 274.4 N · s · m⁻¹, and 0.173); and non-players (19457 N · m⁻¹, 281.5 N · s · m⁻¹, and 0.184). When analysed according to position, the results were as follows: defender (21447 N · m⁻¹, 308.6 N · s · m⁻¹, and 0.189); midfielder (20762 N · m⁻¹, 250.7 N · s · m⁻¹, and 0.157); winger (21322 N · m⁻¹, 335.1 N · s · m⁻¹, and 0.212); forward (22085 N · m⁻¹, 416.2 N · s · m⁻¹, and 0.254); and non-players (19457 N · m⁻¹, 281.5 N · s · m⁻¹, and 0.184). Thus, football training, football games, and the position played had no effect on triceps surae mechanical properties. These results may be attributed to opposing adaptations between different types of training that are usually implemented in football. Alternatively, the minimum strain amplitude and/or frequency threshold of the triceps surae required to trigger adaptations of mechanical properties might not be achieved by football players with football training and matches.


Assuntos
Articulação do Tornozelo , Perna (Membro) , Músculo Esquelético , Educação Física e Treinamento , Amplitude de Movimento Articular , Corrida , Futebol , Adolescente , Adulto , Atletas , Fenômenos Biomecânicos , Futebol Americano , Humanos , Masculino , Adulto Jovem
14.
Anal Bioanal Chem ; 403(1): 93-129, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22318697

RESUMO

Fluoroquinolones are one of the most promising and intensively studied drugs of contemporary anti-infective chemotherapy. New fluoroquinolone antibacterials with improved pharmacokinetic properties and a broad spectrum of activity have been developed, opening new windows of opportunity for clinical use. To our knowledge, no comprehensive and critical review of the analytical methods for the determination of these agents, which correspond to the third- and fourth-generation quinolones, has yet been published. This work summarizes for the first time most of the liquid chromatographic methods reported in the literature for the separation and quantification of the new fluoroquinolones in biological matrices and pharmaceutical formulations. A systematic and detailed survey of physicochemical properties, sample preparation procedures, and chromatographic and detection conditions is presented herein. In the course of this review several liquid chromatographic methods are discussed: reversed-phase high-performance liquid chromatography (RP-HPLC), ion-exchange high-performance liquid chromatography (IEX-HPLC), hydrophilic interaction liquid chromatography (HILIC), high-performance thin-layer chromatography (HPTLC) and other chiral chromatographic methods. Their advantages, applicability and limitations are also examined.


Assuntos
Cromatografia Líquida/métodos , Fluoroquinolonas/análise , Preparações Farmacêuticas/análise , Fluoroquinolonas/farmacocinética , Fluoroquinolonas/farmacologia
15.
Artigo em Inglês | MEDLINE | ID: mdl-35409757

RESUMO

In athletics sprint events, the block start performance can be fundamental to the outcome of a race. This Systematic Review aims to identify biomechanical factors of critical importance to the block start and subsequent first two steps performance. A systematic search of relevant English-language articles was performed on three scientific databases (PubMed, SPORTDiscus, and Web of Science) to identify peer-reviewed articles published until June 2021. The keywords "Block Start", "Track and Field", "Sprint Running", and "Kinetics and Kinematics" were paired with all possible combinations. Studies reporting biomechanical analysis of the block start and/or first two steps, with track and field sprinters and reporting PB100m were sought for inclusion and analysis. Thirty-six full-text articles were reviewed. Several biomechanical determinants of sprinters have been identified. In the "Set" position, an anthropometry-driven block setting facilitating the hip extension and a rear leg contribution should be encouraged. At the push-off, a rapid extension of both hips and greater force production seems to be important. After block exiting, shorter flight times and greater propulsive forces are the main features of best sprinters. This systematic review emphasizes important findings and recommendations that may be relevant for researchers and coaches. Future research should focus on upper limbs behavior and on the analysis of the training drills used to improve starting performance.


Assuntos
Desempenho Atlético , Corrida , Atletismo , Aceleração , Fenômenos Biomecânicos
16.
Materials (Basel) ; 15(17)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36079381

RESUMO

Cement paste powder (CPP) is a by-product of the recycling process of concrete with an elevated carbonation capability and potential to be recycled as a binding material in new concrete batches. The application of a carbonation treatment to CPP improves this potential even more, besides the evident gains in terms of CO2 net balance. However, the long duration usually adopted in this treatment, from 3 to 28 days, hampers the industrial viability of the process. We studied the feasibility of a short-duration carbonation process, with a duration of two hours, carrying out a comprehensive characterization of the material throughout the process. The test was performed on CPP with an average initial water content of 16.9%, exposed to a CO2 concentration of 80%. The results demonstrate two main carbonation rates: a rapid growth rate in the first 18 minutes of the process, involving all the calcium-bearing compounds in CPP, and a slow growth rate afterwards, where only C-S-H contributes to the carbonation reaction. During the 2 h carbonation process, the main CPP compounds, calcium silicate hydrate (C-S-H) and calcium hydroxide (CH), reached different carbonation degrees, 31% and 94%, with, however, close CO2 uptake values, 8% and 11%, respectively. Nevertheless, the total CO2 uptake for this process (≈19%) attained values not distant from the values usually obtained in a carbonation of 12 days or more (19-25%). Hence, these findings highlight the blocking role of C-S-H in the carbonation process, indicating that longer carbonation periods are only going to be useful if an effective carbonation of this compound is accomplished. In the present scenario, where CH is the main contributor to the reaction, the reduction in the process duration is feasible.

17.
Animals (Basel) ; 11(6)2021 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-34067449

RESUMO

Injuries to the locomotor system are a common problem in athletic horses. Veterinarians address these injuries using appropriate medical, surgical, and pharmacological treatments. During or after recovery from the initial injury, horses may be treated for functional locomotor deficits using specific rehabilitation techniques aimed at restoring full athletic performance. This study reviews the literature to identify which rehabilitative techniques have been used most frequently in horses over the past 20 years, the protocols that were used, and the outcomes of the treatments in naturally occurring injuries and diseases. Publications were identified using keyword selection (Equine Athlete OR Equine OR Horse) AND (Rehabilitation OR Physiotherapy OR Physical Therapy). After removing duplicates and screening papers for suitability, 49 manuscripts were included in the study. The majority of publications that met the inclusion criteria were narrative reviews (49%) in which the authors cited the relatively small number of published evidence-based studies supplemented by personal experience. Observational/descriptive studies were also popular (35%). Randomized control trials accounted for only 10%. The most frequently reported rehabilitation techniques were exercise, electrotherapy, and hydrotherapy. The findings highlight the need for further information regarding type of intervention, parameterization, and outcomes of equine rehabilitation in clinical practice.

18.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 4808-4811, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34892285

RESUMO

This study presents and applies fractal Brownian motion assessment of the center of pressure (COP) excursion during feet ground contact on standard vertical jump impulse phase with long and short countermovement (CM) in relation with lower limb muscle stretch-shortening cycle (SSC) comparing it with no CM and SSC. Fifty-four tests were performed by a group of six healthy male students of sports and physical education degree without previous injury, specific training, or fitness ability. Three repetitions were performed by each subject of a squat jump (SJ) without CM and SSC, countermovement jump (CMJ) with long CM and SSC, as well as drop jump (DJ) with short CM and SSC after depth jump from a 40 cm step. During trial tests ground reaction force and force moments were acquired with force platform and impulse phases were segmented for COP coordinates computation. Fractal Brownian motion analysis of COP excursion during impulse phases conduced to detection of differences between critical time and displacement as well as short and long-term diffusion coefficient (Ds, Dl) and Hurst index scale exponent (Hs, Hl), with Ds, Dl presenting statistical significative correlations -0.491, -0.559 and Hs, Hl non statistical significative correlations 0.266 and -0.424 with MVJ height (ht) at 5% significance for explaining underlying mechanisms on CM and SSC at MVJ.Clinical Relevance- This work contributes with new method for the study expansion of the center of pressure excursion and stability during feet ground contact from orthostatic standing position to the impulse phase during standard maximum vertical jump as the most adequate method for assessment of lower limb muscle stretch-shortening cycle.


Assuntos
Fractais , Esportes , Exercício Físico , , Humanos , Masculino
20.
BMJ Case Rep ; 12(6)2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31229971

RESUMO

A 34-year-old multipara presented 72 hours postpartum with acute right-sided abdominal pain. The investigation revealed mild leucocytosis with positive D-dimer and elevated C reactive protein. Abdominal ultrasound and abdominopelvic CT demonstrated an enlarged right ovarian vein with endoluminal thrombus, representing postpartum ovarian vein thrombosis. The patient became asymptomatic 48 hours after starting broad-spectrum antibiotic treatment and anticoagulant therapy. She completed the treatment in ambulatory regimen and control abdominopelvic CT imaging was performed and revealed a duplicated right ovarian vein and a small residual subacute thrombus in the lumen of the distal right ovarian vein. The patient remained asymptomatic in the clinical follow-up.


Assuntos
Dor Abdominal/diagnóstico por imagem , Ovário/irrigação sanguínea , Período Pós-Parto , Transtornos Puerperais/diagnóstico por imagem , Trombose Venosa/diagnóstico por imagem , Dor Abdominal/tratamento farmacológico , Dor Abdominal/fisiopatologia , Adulto , Antibacterianos/uso terapêutico , Anticoagulantes/uso terapêutico , Feminino , Humanos , Ovário/diagnóstico por imagem , Transtornos Puerperais/tratamento farmacológico , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Trombose Venosa/tratamento farmacológico , Trombose Venosa/fisiopatologia
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