O26 Polysaccharides as Key Players in Enteropathogenic E. coli Immune Evasion and Vaccine Development.

Enteropathogenic Escherichia coli (EPEC) produce a capsule of polysaccharides identical to those composing the O-antigen polysaccharide of its LPS (lipopolysaccharide) molecules. In light of this, the impact of O26 polysaccharides on the immune evasion mechanisms of capsulated O26 EPEC compared to non-capsulated enterohemorrhagic Escherichia coli (EHEC) was investigated. Our findings reveal that there was no significant difference between the levels in EPEC and EHEC of rhamnose (2.8:2.5), a molecule considered to be a PAMP (Pathogen Associated Molecular Patterns). However, the levels of glucose (10:1.69), heptose (3.6:0.89) and N-acetylglucosamine (4.5:2.10), were significantly higher in EPEC than EHEC, respectively. It was also observed that the presence of a capsule in EPEC inhibited the deposition of C3b on the bacterial surface and protected the pathogen against lysis by the complement system. In addition, the presence of a capsule also protected EPEC against phagocytosis by macrophages. However, the immune evasion provided by the capsule was overcome in the presence of anti-O26 polysaccharide antibodies, and additionally, these antibodies were able to inhibit O26 EPEC adhesion to human epithelial cells. Finally, the results indicate that O26 polysaccharides can generate an effective humoral immune response, making them promising antigens for the development of a vaccine against capsulated O26 E. coli.

Interaction of Biomechanical, Anthropometric, and Demographic Factors Associated with Patellofemoral Pain in Rearfoot Strike Runners: A Classification and Regression Tree Approach.

BACKGROUND: Patellofemoral pain (PFP) is among the most common injuries in runners. While multiple risk factors for patellofemoral pain have been investigated, the interactions of variables contributing to this condition have not been explored. This study aimed to classify runners with patellofemoral pain using a combination of factors including biomechanical, anthropometric, and demographic factors through a Classification and Regression Tree analysis. RESULTS: Thirty-eight runners with PFP and 38 healthy controls (CON) were selected with mean (standard deviation) age 33 (16) years old and body mass index 22.3 (2.6) kg/m2. Each ran at self-selected speed, but no between-group difference was identified (PFP = 2.54 (0.2) m/s x CON = 2.55 (0.1) m/s, P = .660). Runners with patellofemoral pain had different patterns of interactions involving braking ground reaction force impulse, contact time, vertical average loading rate, and age. The classification and regression tree model classified 84.2% of runners with patellofemoral pain, and 78.9% of healthy controls. The prevalence ratios ranged from 0.06 (95% confidence interval: 0.02-0.23) to 9.86 (95% confidence interval: 1.16-83.34). The strongest model identified runners with patellofemoral pain as having higher braking ground reaction force impulse, lower contact times, higher vertical average loading rate, and older age. The receiver operating characteristic curve demonstrated high accuracy at 0.83 (95% confidence interval: 0.74-0.93; standard error: 0.04; P < .001). CONCLUSIONS: The classification and regression tree model identified an influence of multiple factors associated with patellofemoral pain in runners. Future studies may clarify whether addressing modifiable biomechanical factors may address this form of injury.

Effects of two gait retraining programs on pain, function, and lower limb kinematics in runners with patellofemoral pain: A randomized controlled trial.

BACKGROUND: Patellofemoral Pain (PFP) is one of the main injuries in runners. Consistent evidence support strengthening programs to modulate symptoms, however, few studies investigated the effects of gait retraining programs. OBJECTIVE: To investigate the effects of two different two-week partially supervised gait retraining programs on pain, function, and lower limb kinematics of runners with PFP. METHODS: Randomized controlled trial. Thirty runners were allocated to gait retraining groups focusing on impact (n = 10) or cadence (n = 10), or to a control group (n = 10). Impact group received guidance to reduce tibial acceleration by 50%, while cadence group was asked to increase cadence by 7.5-10%. The control group did not receive any intervention. Usual and running pain, knee function, and lower limb kinematics (contralateral pelvic drop, hip adduction, knee flexion, ankle dorsiflexion, tibia inclination, and foot inclination) were evaluated before (T0), immediately after the intervention (T2), and six months after the protocol (T24). RESULTS: A significant group x time interaction was found for running pain (p = 0.010) and knee function (p = 0.019). Both programs had greater improvements in running pain compared to no intervention at T24 (Impact x Control-mean difference (MD) -3.2, 95% CI -5.1 to -1.3, p = 0.001; Cadence x Control-MD -2.9, 95% CI -4.8 to -1.0, p = 0.002). Participants of the impact group had greater improvements in knee function compared to no intervention at T2 (Impact x Control-MD 10.8, 95% CI 1.0 to 20.6, p = 0.027). No between-group differences in usual pain and lower limb kinematics were found (p>0.05). CONCLUSION: Compared to no intervention, both programs were more effective in improving running pain six months after the protocol. The program focused on impact was more effective in improving knee function immediately after the intervention. Clinical trial registry number: RBR-8yb47v.

O26 Polysaccharides as key players in enteropathogenic E. coli immune evasion and vaccine development

Enteropathogenic Escherichia coli (EPEC) produce a capsule of polysaccharides identical to those composing the O-antigen polysaccharide of its LPS (lipopolysaccharide) molecules. In light of this, the impact of O26 polysaccharides on the immune evasion mechanisms of capsulated O26 EPEC compared to non-capsulated enterohemorrhagic Escherichia coli (EHEC) was investigated. Our findings reveal that there was no significant difference between the levels in EPEC and EHEC of rhamnose (2.8:2.5), a molecule considered to be a PAMP (Pathogen Associated Molecular Patterns). However, the levels of glucose (10:1.69), heptose (3.6:0.89) and N-acetylglucosamine (4.5:2.10), were significantly higher in EPEC than EHEC, respectively. It was also observed that the presence of a capsule in EPEC inhibited the deposition of C3b on the bacterial surface and protected the pathogen against lysis by the complement system. In addition, the presence of a capsule also protected EPEC against phagocytosis by macrophages. However, the immune evasion provided by the capsule was overcome in the presence of anti-O26 polysaccharide antibodies, and additionally, these antibodies were able to inhibit O26 EPEC adhesion to human epithelial cells. Finally, the results indicate that O26 polysaccharides can generate an effective humoral immune response, making them promising antigens for the development of a vaccine against capsulated O26 E. coli.

Posturography measures in specific ballet stance position discriminate ballet dancers with different occurrences of musculoskeletal injuries.

BACKGROUND: This study aimed to identify the postural sway variables that can distinguish between ballet dancers with high and low occurrences of musculoskeletal injuries. METHODS: Fourteen professional ballet dancers were assigned to a high-occurrence group (N = 5, reports >2 injuries in the previous 6-months) or a low-occurrence group (N = 9, reports ≤1 injury). Center-of-pressure (COP) data were acquired using a force platform during the following tasks: single-leg stance with eyes open, single-leg stance with eyes closed, and demi-pointe stance with eyes open. The COP standard deviation (SD) and range (RA) in both the medial-lateral (ML) and anterior-posterior (AP) directions were estimated. Between-group comparisons were made through Welch's t-tests for unequal sample size along the effect size measure (Cohen's d). Spearman's rho was used to estimate the association between the number of injuries and the COP variables. The statistical threshold was set at 1%. RESULTS: A between-group effect was found only for the demi-pointe stance, with large effects for SDML (P = 0.006, d = 1.7), RAAP (P = 0.006, d = 1.7), and RAML (P = 0.005, d = 1.7). An inverse relationship was found between the number of injuries and the demi-pointe's COP range in both directions (Spearman's rho from -0.681 to -0.726, P = 0.007). CONCLUSIONS: COP measures taken in ballet-specific positions can distinguish between dancers with a high and low occurrence of musculoskeletal injuries. Suggestions are made to include ballet-specific tasks in the functional assessments of professional dancers.

Agreement and predictive performance of fall risk assessment methods and factors associated with falls in hospitalized older adults: A longitudinal study.

Falls in hospitalized older adults are of concern and, despite the availability of fall risk assessment methods and knowledge about factors associated with falls, their validity and agreement remain poorly investigated. In a prospective study, we enrolled 102 hospitalized older adults (median [P25-P75]) 67 (64-73) years, 52 [51%] men, length of stay 20 [8-41] days). Fall risk was assessed at hospital admission using the Functional Independence Measure; Morse Fall Scale; St. Thomas's Risk Assessment Tool in Falling Elderly Inpatients; Johns Hopkins Fall Risk Assessment Tool; and polypharmacy. The St. Thomas's Risk Assessment Tool in Falling Elderly Inpatients method showed the highest predictive performance (accuracy 92%) for the identification of fallers during hospitalization. A slightly better-then-chance agreement was estimated between all methods (Light's κ = 0.120). Fall risk assessment methods and factors associated with falls should not be used interchangeably as their overall and pairwise agreement are fair at best.

Poststroke consequences upon optimization properties of postural sway during upright stance: a cross-sectional study.

BACKGROUND: The understanding of human postural control has advanced with the introduction of optimization process modeling. These models, however, only provide control parameters, rather than analytical descriptors of optimization processes. Here, we use a newly developed direct (pattern) search algorithm to investigate changes in postural optimization process in poststroke individuals. OBJECTIVE: This cross-sectional study investigated the optimization properties of postural stability during upright standing in poststroke individuals. METHODS: Twenty-nine poststroke and 15 healthy age-matched individuals underwent posturography with a force platform while standing for 60 s for acquisition of center-of-pressure data. Poststroke individuals were grouped depending on their weight-bearing (WB) pattern and their balance capability assessed through Berg Balance Scale (BBS). The optimization properties of postural stability were computed assuming the minimization of postural sway as cost function. RESULTS: The asymmetric WB poststroke group showed larger convergence rate toward the local minimum of postural sway than the symmetric WB group. Additionally, the low-balance capability group exhibited smaller values for averaged local minima and global minimum of postural sway coordinates compared with high-balance capability group. Significant correlations were found for BBS and the local minima and global minimum (Pearson's r ranged 0.378-0.424, P < 0.05). CONCLUSIONS: In summary, the optimization properties describing postural dynamic stability, steadiness, and global reference are altered in poststroke individuals with asymmetric WB pattern and low-balance capability.

Comparison of the upper extremity physical performance tests between asymptomatic adults with and without scapular dyskinesis

Abstract Introduction Physical performance tests (PPTs) are screening tools widely available, easy to apply, and that can be performed in different environments and contexts. Scapular dyskinesis can be related to changes in glenohumeral angulation, acromioclavicular joint strain, subacromial space dimension, shoulder muscle strength/activation and humeral position/motion. Few studies were developed to understand the influence of aspects such as strength, stability mobility, and scapular dyskinesis on the scores of the upper extremity PPTs. Objective To compare the performance in the Closed Kinetic Chain Upper Extremity Stability Test (CKCUEST), Seated Medicine Ball Throw Test (SMBT) and Upper Quarter Y Balance Test (UQYBT) between asymptomatic adults with and without scapular dyskinesis. Methods Cross-sectional study with 20 asymptomatic individuals: 10 with scapular dyskinesis and 10 without scapular dyskinesis. The average number of touches, number of touches normalized by height, and power score in the CKCUEST, distance covered by the ball in the SMBT, reach in the medial, inferolateral, and superolateral directions, total excursion and composite score of the UQYBT were compared between both groups. Results No significant differences were found for all variables (p > 0.05). Small to moderate effect sizes were found for the scores of the CKCUEST (d = 0.16-0.78), a small effect size was found for the distance in the SBMT (d = 0.12), and small to moderate effect sizes were found for the scores of the UQYBT (d = 0.02-0.43). The scapular dyskinesis group presented better performance in all tests. Conclusion The presence of scapular dyskinesis in asymptomatic individuals is not a factor related to worse scores in upper extremity physical performance tests.

Resumo Introdução Os testes de desempenho físico (PPTs) são instrumentos de triagem amplamente disponíveis, de fácil aplicação e que podem ser realizados em diferentes ambientes e contextos. A discinesia escapular pode estar relacionada a alterações na angulação glenoumeral, tensão na articulação acromioclavicular, dimensão do espaço subacromial, força/ativação muscular do ombro e posição/movimento umeral. Poucos estudos foram desenvolvidos para entender a influência de aspectos como força, estabilidade, mobilidade e discinese escapular nos escores dos PPTs de membros superiores. Objetivo Comparar o desempenho no Teste de Estabilidade de Extremidade Superior de Cadeia Cinética Fechada (CKCUEST), Teste de Arremesso de Medicine Ball Sentada (SMBT) e Teste de Equilíbrio em Y do Quarto Superior (UQYBT) entre adultos assintomáticos com e sem discinesia escapular. Métodos Estudo transversal com amostra de 20 indivíduos assintomáticos: 10 com discinesia escapular e 10 sem discinesia escapular. Comparou-se o número médio de toques, número de toques normalizados pela altura e pontuação de potência no CKCUEST, distância percorrida pela bola no SMBT, alcance nas direções medial, inferolateral e superolateral, excursão total e escore composto do UQYBT entre ambos os grupos. Resultados Não foram encontradas diferenças significativas para todas as variáveis (p > 0,05). Tamanho de efeito pequeno a moderado foi encontrado para os escores do CKCUEST (d = 0,16-0,78), tamanho de efeito pequeno foi encontrado para a distância no SBMT (d = 0,12) e tamanho de efeito pequeno a moderado foi encontrado para as pontuações do UQYBT (d = 0,02-0,43). O grupo com discinesia escapular apresentou melhor desempenho em todos os testes. Conclusão A pre-sença de discinesia escapular em indivíduos assintomáticos não é um fator relacionado a piores escores em testes de desempenho físico de membros superiores.

Body sway and movement strategies for control of postural stability in people with spinocerebellar ataxia type 3: A cross-sectional study.

BACKGROUND: Postural instability with an excessive body sway is a disabling manifestation in spinocerebellar ataxia type 3. Whether the larger body sway reflects distinct movement strategies for postural control remains uncertain. This study compared the control of postural stability of people with spinocerebellar ataxia type 3 with healthy subjects using body sway and movement strategy analyses derived from bi- and three-dimensional posturography. METHODS: Twenty-three patients (7 men, 16 women, 47 ± 11 years) and 102 healthy participants (34 men, 68 women; 44 ± 22 years) underwent posturography while standing with eyes open/closed tasks. Postural stability was assessed using elliptical area and average velocity of body sway. Spatial patterns (single-, double-, or multi-centered) were derived from the number of high-density regions in the three-dimensional statokinesigram. FINDINGS: Repeated measures two-way analysis-of-variance showed a vision-by-group interaction effect for area (F1,122 = 28.831, P < 0.001, η2 = 0.037) and velocity (F1,123 = 59.367, P < 0.001, η2 = 0.073); sway area and velocity were higher in spinocerebellar ataxia type 3 and increased under eyes-closed condition, with a higher increase in the spinocerebellar ataxia type 3. A main effect for group (F1,123 = 11.702, P < 0.001, η2 = 0.061) but not vision (F1,123 = 2.257, P = 0.136, η2 = 0.005) was found for the number of high-density regions. Spatial patterns were different between groups under trials with eyes closed (χ22,125 = 7.46, P = 0.023) but not open (χ22,125 = 2.026, P = 0.363), with a shift from single- to double- or multi-centered spatial patterns. INTERPRETATION: Compared to healthy subjects, a larger body displacement and velocity in spinocerebellar ataxia type 3, mainly under visual constraints, are not related to the predominance of either ankle or hip movement strategies.

Concurrent validity of the inertial sensors for assessment of balance control during quiet standing in patients with chronic low back pain and asymptomatic individuals.

The objective was to investigate the concurrent validity of inertial sensors for measuring balance control in patients with chronic low back pain and asymptomatic individuals. Thirty-nine patients with chronic low back and 39 age- and sex-matched asymptomatic individuals were included. Balance control analysis was performed in quiet standing with two inertial sensors positioned at the lumbar region and the sternum and compared to the results of a force plate. The variables analysed with either device were Root Mean Square (RMS), index of smoothness (JERK), trajectory length (PATH) and area (AREA). Spearman's correlation coefficient investigated the correlation. Patients with chronic low back pain showed moderate correlation with the inertial sensor positioned on the lumbar for RMS (rs = 0.59; p < 0.01), PATH (rs = 0.42, p = 0.01) and AREA (rs = 0.59; p < 0.01) and weak correlation with the inertial sensor positioned on the sternum for PATH (rs = 0.36, p = 0.04). The asymptomatic group showed statistically significant correlations for RMS for the lumbar (rs = 0.38; p = 0.03) and sternum inertial sensor (rs = 0.42; p = 0.02). Inertial sensors showed weak to moderate correlations compared to data obtained from a force plate.

Conhecimento, interesse e preferência por programas de retreinamento de corrida em corredores de rua: estudo transversal / Conocimiento, interés y preferencia por programas de reentrenamiento de corrida en los corredores de calle: un estudio transversal / Knowledge, interest, and preference for gait retraining programs in street runners: a cross-sectional study

RESUMO Com o intuito de prevenir ou reabilitar lesões musculoesqueléticas relacionadas à corrida, algumas modalidades de tratamento têm sido utilizadas, entre elas o retreinamento de corrida. O objetivo deste estudo foi avaliar o conhecimento, o interesse e a preferência acerca de programas de retreinamento de corrida por parte de corredores de rua e verificar se esses aspectos diferem entre corredores sem e com histórico de lesão. Trata-se de estudo transversal feito com 100 corredores. Inicialmente, um texto mostrando do que se tratava o retreinamento de corrida foi apresentado aos participantes, que então responderam com relação ao conhecimento (sim ou não) e ao interesse na realização (sim ou não). Posteriormente, um texto mostrando como seria a realização de um programa supervisionado e outro parcialmente supervisionado foi apresentado aos participantes, que responderam acerca de sua preferência por um deles (supervisionado ou parcialmente supervisionado). Constatou-se que a maioria desconhece os programas de retreinamento de corrida (69,8%), porém houve um alto interesse (87,1%) na realização do programa após a leitura do texto. Os participantes não apresentaram preferência por um protocolo totalmente supervisionado (48,2%) ou parcialmente supervisionado (51,8%). Foi encontrada uma diferença estatística quanto ao conhecimento (p=0,029) a favor dos participantes com histórico de lesão. Apesar das crescentes evidências disponíveis, observou-se que a maioria dos corredores não tem conhecimento prévio sobre esta modalidade. Devido ao alto interesse e à ausência de preferência por diferentes protocolos, sugere-se que os programas descritos sejam apresentados aos pacientes por profissionais da saúde que trabalhem com essa população.

RESUMEN Con el propósito de prevenir o rehabilitar las lesiones musculoesqueléticas relacionadas con la carrera, el reentrenamiento de carrera es una de las modalidades de tratamiento. El objetivo de este estudio fue evaluar el conocimiento, el interés y la preferencia por los programas de reentrenamiento de carrera por parte de corredores de calle, así como verificar si estos aspectos difieren entre los corredores sin antecedentes de lesiones o con. Se trata de un estudio transversal, realizado con 100 corredores. Inicialmente, los participantes recibieron un texto sobre el reentrenamiento de corrida y, luego, respondieron acerca del conocimiento (sí o no) y el interés por hacerlo (sí o no). Enseguida, los participantes recibieron un texto sobre cómo aplicar un programa supervisado y otro sobre el programa parcialmente supervisado, y respondieron su preferencia por uno de ellos (supervisado o parcialmente supervisado). Se constató que la mayoría de los respondientes desconoce los programas de reentrenamiento de corrida (69,8%), pero hubo un gran interés (87,1%) por aplicar el programa después de la lectura del texto. Los participantes no mostraron preferir un protocolo totalmente supervisado (48,2%) o parcialmente supervisado (51,8%). Se encontró una diferencia estadística en cuanto al conocimiento (p=0,029) sobre los participantes con antecedentes de lesión. A pesar de la creciente y disponible evidencia, se observó que la mayoría de los corredores no tienen conocimiento previo de esta modalidad. Debido al gran interés y la falta de preferencia por uno de los protocolos, los programas descritos deberían de ser presentados a los pacientes por los profesionales de la salud que trabajan con esta población.

ABSTRACT Some treatment modalities have been used to prevent or treat running-related musculoskeletal injuries, among them, gait retraining. This study aimed to evaluate street runners' knowledge, interest, and preference for gait retraining programs and assess if these aspects differ between runners with and without history of injury. This is a cross-sectional study with 100 runners. Initially, a text showing what gait retraining was about was presented to participants. Then, they answered questions about their knowledge (yes x no) and interest (yes x no) on the programs. Subsequently, a text showing how fully and partially supervised programs would be conducted was offered to participants. Then, they reported their preference for one of them (fully x partially supervised). We found that most athletes were unaware of gait retraining programs (69.8%), though they showed great interest in performing them after explanation (87.1%). We observed no preference for a fully (48.2%) or partially supervised (51.8%) protocol. We also found a statistical difference in knowledge (p=0.029) in favor of participants with history of injury. Despite the growing evidence available, we observed that most runners lack any prior knowledge of this modality. Due to the great interest and lack of preference for different protocols shown, we suggest that healthcare providers who treat this population offer the programs described to patients.

Postural control in football players with vision impairment: Effect of sports adaptation or visual input restriction?

Abstract Aim: To assess the postural control performance of football 5-a-side (FFS) players, comparing them with sighted players. Methods: Eight FFS players and 7 sighted futsal players were included. Postural control tests included feet together stance (FTS) and single-leg stance (SLS) tasks, performed on rigid and foam surfaces. Sighted players performed the tests with open (EO) and closed (EC) eyes. Area of displacement (Area) and average velocity (Vavg) were calculated from the center of pressure time-series coordinates. Results: On both surfaces conditions, a significant difference between visually impaired football 5-a-side players and sighted EO players was observed during FTS (higher Vavg for visually impaired football 5-a-side players; p < 0.04) and SLS (higher Area and Vavg for visually impaired football 5-a-side players; p < 0.01). No differences between visually impaired football 5-a-side players and sighted EC players were found. Differences between sighted EO vs. sighted EC were observed during FTS on the foam surface, and in SLS on both surface conditions (p < 0.03). Conclusion: FFS players' postural control performance is similar to sighted players with EC but worse than sighted players with EO, suggesting their postural control performance can be simply explained in terms of visual restriction.

Reliability and validity of the One Arm Hop Test and Seated Medicine Ball Throw Test in young adults: A cross-sectional study.

BACKGROUND: Functional performance tests are inexpensive, accessible, and easy to apply tools that can be used to help practitioners in daily decision making process. The purpose of this study was to evaluate the reliability and validity of the One Arm Hop Test (OAHT) and Seated Medicine Ball Throw Test (SBMT) in young adults. METHODS: Cross-sectional study with a sample consisted of 59 young adults. The subjects performed the OAHT and SMBT in two moments separated by seven days and by two examiners. The Closed Kinetic Chain Upper Extremity Stability Test (CKCUEST) was performed at the second moment. The time in OAHT, distance in SMBT, mean number of touches, normalized score, and power of the CKCUEST were measured. Reliability was determined using Intraclass Correlation Coeficient (ICC) and Bland-Altman Plots. Validity was assessed via Pearson's Correlation Coefficient (r) between these tests and CKCUEST. RESULTS: We found good reliability of the OAHT between different raters (dominant limb - ICC = 0.83; non-dominant limb - ICC = 0.80) and moderate reliability between the same rater (dominant limb - ICC = 0.63; non-dominant limb - ICC = 0.62). In the SMBT we found good reliability inter-examiner (ICC = 0.84) and intra-examiner (ICC = 0.77). Low to moderate correlations with the CKCUEST were found (r < 0.70; p < 0.05). CONCLUSIONS: The OAHT and the SMBT show moderate/good reliability intra and inter-examiner, however these tests are poorly correlated with CKCUEST. The SMBT presented higher values of ICC than OAHT. A combination of the SMBT and CKCUEST is recommended in clinical practice.

Concurrent validation of the centre of pressure displacement analyzed by baropodometry in patients with chronic non-specific low back pain during functional tasks.

INTRODUCTION: Low back pain is highly prevalent worldwide and in Brazil. Postural control is a functional limitation in patients with low back pain. Postural control can be investigated through the centre of pressure (CoP) displacement, using a baropodometry. However, there is a lack of validation data about posturography variables obtained from the baropodometer. This study aimed to investigate the concurrent validity of the displacement of CoP measured through baropodometer T-Plate® in patients with chronic non-specific low back pain during three tasks. METHOD: A validation study was conducted in 37 participants with chronic non-specific low back pain during three different tasks, including bipedal support, bipedal support holding bags, and bipedal squatting holding bags. The tasks were performed on a baropodometer (index method) placed on a force plate (criterion measure). Measurements included velocity, amplitude of displacement, and sway area. RESULTS: Weak to strong correlations were found in the three tasks between the baropodometer and the force plate for most variables. The Bland-Altman analyses revealed no substantive differences between the two methods for the standard deviation of amplitude mediolateral and sway area for the three tasks. There was a systematic bias for the mean velocity and the standard deviation of amplitude anteroposterior displacement in the three tasks. CONCLUSION: The baropodometer could be used to measure the displacement of the CoP in patients with chronic non-specific low back pain. Sway area showed an appropriate validity to measure postural stability of the participants using the baropodometer.

Influência do estímulo visual e posição dos membros superiores no controle postural ortostático de crianças e adolescentes / Influence of visual stimulus and upper limbs' position in the orthostatic postural control of children and adolescents

O objetivo do estudo foi verificar a influência do estímulo visual e posicionamento dos membros superiores no controle postural ortostático e avaliar o efeito do sexo e idade nas respostas posturais de crianças e adolescentes. Estudo transversal, com amostra de 84 participantes com idade entre 11 e 14 anos, ambos os sexos (55 meninas), de escola pública de Goiânia (GO). Além do exame físico, o controle postural foi avaliado na posição ortostática pela baropodometria computadorizada em três condições: olhos abertos, olhos fechados e olhos abertos com ombros a 90° de abdução. A ausência do estímulo visual gerou maior instabilidade postural em comparação à condição de olhos abertos. Em relação as diferenças existentes entre os sexos, foi observado que as meninas tiveram menores valores de deslocamento anteroposterior e área da elipse que os meninos. Comparando-se os olhos abertos e fechados, as meninas apresentaram maiores valores na área da elipse e os meninos nos deslocamentos anteroposterior e látero-lateral. Ao analisar o efeito da idade foi observado que o grupo com 13 e 14 anos apresentou maiores valores em todas as variáveis analisadas. A ausência do estímulo visual aumentou os valores da área da elipse no grupo com 11 e 12 e dos deslocamentos no grupo com 13 e 14 anos. Não foi verificado efeito interativo entre sexo e idade. Na condição de abdução dos membros superiores não houve diferença no controle postural. Conclui-se que a ausência do estímulo visual foi mais impactante na manutenção do controle postural ortostático em crianças e adolescentes em relação as outras condições avaliadas, existindo diferença entre os sexos e a idade, em que os meninos e o grupo com 13 e 14 anos realizaram mais ajustes para manter o controle postural. (AU)

The aim of this study was to verify the influence of visual stimulus and positioning of the upper limbs in the orthostatic postural control, and to assess the effects of gender and age in the postural responses of children and adolescents. This was a transversal study involving 84 participants (of which 55 were girls) from public schools in Goiania (GO - Brazil) with age between 11 and 14 years. Besides physical examination, the participants' postural control was assessed in the orthostatic position by computerized baropodometry in three different conditions: eyes-open, eyes-closed, and eyes-open with shoulders at 90º abduction. The absence of visual stimulus generated more postural instability in relation to the eyes-open condition. Regarding gender differences, the girls had lower anteroposterior and ellipse area displacement than boys. Comparing the eyes-open and eyes-closed conditions, the girls presented higher values in the ellipse area and the boys presented higher values in the anteroposterior and laterolateral displacements. Analyzing the effect of age, the participants between 13 and 14 years old presented higher values in all variables. The absence of visual stimulus increased the values of the ellipse area in the participants between 11 and 12 years of age and the values of displacements in the participants between 13 and 14 years of age. Interactive effect between genders and age has not been verified. There were no postural control differences in the upper limbs abduction condition. Conclusion: The absence of visual stimulus was more impacting in the support of orthostatic postural control in children and adolescents than the other conditions assessed; the boys and the participants between 13 and 14 years of age made more adjustments in order to maintain postural control. (AU)

Effects of gait retraining with focus on impact versus gait retraining with focus on cadence on pain, function and lower limb kinematics in runners with patellofemoral pain: Protocol of a randomized, blinded, parallel group trial with 6-month follow-up.

Patellofemoral pain (PFP) is one of the most prevalent injuries in runners. Unfortunately, a substantial part of injured athletes do not recover fully from PFP in the long-term. Although previous studies have shown positive effects of gait retraining in this condition, retraining protocols often lack clinical applicability because they are time-consuming, costly for patients and require a treadmill. The primary objective of this study will be to compare the effects of two different two-week partially supervised gait retraining programs, with a control intervention; on pain, function and lower limb kinematics of runners with PFP. It will be a single-blind randomized clinical trial with six-month follow-up. The study will be composed of three groups: a group focusing on impact (group A), a group focusing on cadence (group B), and a control group that will not perform any intervention (group C). The primary outcome measure will be pain assessed using the Visual Analog Pain scale during running. Secondary outcomes will include pain during daily activities (usual), symptoms assessed using the Patellofemoral Disorders Scale and lower limb running kinematics in the frontal (contralateral pelvic drop; hip adduction) and sagittal planes (foot inclination; tibia inclination; ankle dorsiflexion; knee flexion) assessed using the MyoResearch 3.14-MyoVideo (Noraxon U.S.A. Inc.). The study outcomes will be evaluated before (t0), immediately after (t2), and six months (t24) after starting the protocol. Our hypothesis is that both partially supervised gait retraining programs will be more effective in reducing pain, improving symptoms, and modifying lower limb kinematics during running compared with the control group, and that the positive effects from these programs will persist for six months. Also, we believe that one gait retraining group will not be superior to the other. Results from this study will help improve care in runners with PFP, while maximizing clinical applicability as well as time and cost-effectiveness.

Immediate effects of myofascial release maneuver applied in different lower limb muscle chains on postural sway.

BACKGROUND: There is little evidence about the myofascial release maneuver (MLM) targeting the fascial tissue and its effect on postural balance. This study investigated the immediate effects of the MLM in different lower limb muscle chains on the postural sway of healthy men. METHODS: Sixty-three healthy men (27.2 ± 4.7 years) were randomly assigned to 7 groups (n = 9 each) to receive MLM applied to the lower limb muscle chains (anterior, posterior, medial, lateral, anterior/posterior, and medial/lateral) or placebo intervention. Skin pressure during the 3-min MLM was determined by the visual analog scale between 5 and 7 as previously assessed on participants. Posturography analysis of the elliptical area (Area) and average velocity (Vavg) of the center-of-pressure displacement was performed before and immediately after the MLM in single-leg support and with eyes closed. RESULTS: A two-way repeated measures analysis of variance showed no interaction effect of factors group and time (Area: p = 0.210, ω2 = 0.004; Vavg: p = 0.358, ω2 < 0.001). Within-factor main effect of time was observed for both Area (p < 0.001, ω2 = 0.038) and Vavg (p < 0.001, ω2 = 0.028), with decreased Area and Vavg after all interventions. No between-factor main effect of group was observed for Area or Vavg (MLM or placebo, p = 0.188 or higher). CONCLUSION: MLM applied to the lower limb muscle chains showed no immediate specific effects on postural sway in healthy men. Pre-post effects of MLM were not different from those elicited by a superficial massage. MLM in lower limb muscle chains is not advocated for an immediate improvement of postural balance in this population.

Lysophosphatidic acid (LPA) as a modulator of plasma membrane Ca2+-ATPase from basolateral membranes of kidney proximal tubules.

Lysophosphatidic acid (LPA) acts through the activation of G protein-coupled receptors, in a Ca2+-dependent manner. We show the effects of LPA on the plasma membrane Ca2+-ATPase (PMCA) from kidney proximal tubule cells. The Ca2+-ATPase activity was inhibited by nanomolar concentrations of LPA, with maximal inhibition (~50%) obtained with 20 nM LPA. This inhibitory action on PMCA activity was blocked by Ki16425, an antagonist for LPA receptors, indicating that this lipid acts via LPA1 and/or LPA3 receptor. This effect is PKC-dependent, since it is abolished by calphostin C and U73122, PKC, and PLC inhibitors, respectively. Furthermore, the addition of 10-8 M PMA, a well-known PKC activator, mimicked PMCA modulation by LPA. We also demonstrated that the PKC activation leads to an increase in PMCA phosphorylation. These results indicate that LPA triggers LPA1 and/or LPA3 receptors at the BLM, inducing PKC-dependent phosphorylation with further inhibition of PMCA. Thus, LPA is part of the regulatory lipid network present at the BLM and plays an important role in the regulation of intracellular Ca2+ concentration that may result in significant physiological alterations in other Ca2+-dependent events ascribed to the renal tissue.

Effect of visual condition and physical activity on the plantar pressure distribution in adult and older women / Efeito do sistema visual e atividade física na distribuição da pressão plantar em mulheres adultas e idosas

Abstract The aging process causes changes in the physical and functional conditions, as well as in the foot structure and function. This study aimed to analyze the plantar pressure variation with respect to visual information and physical activity in adult and older women. This was a cross-sectional study that included 142 women (mean age of 67.8 years). Participants responded the anamnesis questionnaire, Mini Mental State Examination, and International Physical Activity Questionnaire. Plantar pressure was assessed using computerized baropodometry. Weight distribution was observed in semitandem positions for the right foot forward and then the left foot forward . Data analysis showed that foot type had no correlation with age (p = 0.37 right foot; p = 0.93 left foot) or level of physical activity (p = 0.28 right foot; p = 0.96 left foot). Moreover, plantar pressure variation showed no significant relationship with age (R2 = 0.2; p = 0.6). In conclusion, plantar pressure variation is not associated with the morphological foot type in women analyzed, as the visual condition did not generate plantar pressure variations when compared to its effect on the classification of plantar arches. Furthermore, level of physical activity was not associated with plantar pressure variation .

Resumo O processo de envelhecimento acarreta alterações nas condições físico-funcionais e na estrutura e função do pé. O objetivo do estudo foi analisar a variação da pressão plantar quanto a informação visual e atividade física em mulheres adultas e idosas. Estudo transversal, com uma amostra de 142 mulheres (média de idade de 67,8 anos). As mulheres responderam ao questionário de anamnese, Mini Exame do Estado Mental (MEEM) e o Questionário Internacional de Atividade Física (IPAQ). O exame da pressão plantar foi realizado pela baropodometria computadorizada. A distribuição da pressão plantar foi observada na posição semitandem com o pé direito na frente e com o pé esquerdo à frente. O tipo de pé não teve relação com a variação da pressão plantar, idade (p = 0,37 pé direito e p = 0,93 pé esquerdo) ou atividade física (p = 0,28 pé direito e p = 0,96 pé esquerdo). A variação da pressão plantar também não mostrou relação significativa com idade (R2 = 0,2 e p = 0,6). Conclui-se que a variação da pressão plantar não está associada com o tipo morfológico do pé das mulheres analisadas, pois a condição visual não gerou variação da pressão plantar quando comparada ao seu efeito na classificação dos arcos plantares. O nível de atividade física não apresentou relação na variação da pressão plantar.

Effects of Kinesio Taping on peak torque and muscle activity in women with low back pain presenting fears and beliefs related to physical activity.

BACKGROUND: KT is an elastic taping that has been widely used as an adjunct to conventional physiotherapy. The purpose of this study was to evaluate the effects of Kinesio Taping on peak torque, muscle fatigue index and muscle activity of erector spinae in women with low back pain presenting fears and beliefs related to physical activity. METHODS: This is a pilot controlled clinical trial. The subjects were divided into two groups according to the Fear Beliefs Avoidance Questionnaire (FABQ): Group A (Patients with no fears and/or beliefs related to physical activity) and Group B (Patients with fears and/or beliefs related to physical activity). The Kinesio Taping was applied in "I" in order to facilitate erector spinae. An isokinetic dynamometer and a surface electromyography were used to evaluate the outcomes. The evaluations were performed without and with the KT. RESULTS: Sample of 16 women equally divided into two groups with similar characteristics regarding age, weight, height, body mass index, functional capacity and pain levels in the evaluations without and with Kinesio Taping. There were within-groups and between-groups differences in the peak torque (p ≤ .05), with better results in the Group B. No differences were found on muscle fatigue index and muscle activity in both groups (p > .05). CONCLUSION: It was concluded that Kinesio Taping had immediate effects in the peak torque of the erector spinae of women with nonspecific chronic low back pain presenting fears and beliefs related to physical activity. It is suggested that such results occurred by placebo effect. NCT: RBR-5xh3ch.