Effects of replica running shoes upon external forces and muscle activity during running

Twelve participants ran (9 km . h(-1)) to test two types of running shoes: replica and original shoes. Ground reaction force, plantar pressure and electromyographic activity were recorded. The shoes were tested randomly and on different days. Comparisons between the two experimental conditions were made by analysis of variance (ANOVA) test (P <= 0.05). The time to first peak, loading rate of the first peak and impulse of the first 75 ms of stance were significantly different between the shoes (P <= 0.05), revealing an increase of impact forces for the replica shoes. The peak plantar pressure values were significantly higher (P <= 0.05) when wearing replica shoes. During running, the contact area was significantly smaller (P <= 0.05) for the replica shoe. The electromyographic activity of the analysed muscles did not show changes between the two shoes in running. These findings suggest that the use of replica running shoes can increase the external load applied to the human body, but may not change the muscle activity pattern during locomotion. This new mechanical situation may increase the risk of injuries in these movements.

Influence of high-heeled shoes on venous function in young women

Background: Walking with high-heeled shoes is a common cause of venous complaints such as pain, fatigue, and heavy-feeling legs. The aim of the study was to clarify the influence of high-heeled shoes on the venous return and test the hypothesis that women wearing different styles of high-heeled shoes present an impaired venous return when compared with their values when they are barefoot. Methods: Thirty asymptomatic women (mean age, 26.4 years) wearing appropriately sized shoes were evaluated by air plethysmography (APG), a test that measures changes in air volume on a cuff placed on the calf, while they performed orthostatic flexion and extension foot movements and altered standing up and lying down. The test was repeated in four situations: barefoot (0 cm), medium heels (3.5 cm), stiletto high heels (7 cm), and platform high heels (7 cm). The APG values of venous filling index (VFI), ejection fraction (EF), and residual volume fraction (RVF) were divided into four groups according to heel height and compared by repeated-measures analysis of variance. Results: RVF was increased in the groups wearing high heels (stiletto and platform) compared with the barefoot group (P < .05). RVF was increased in the medium-heel group (3.5 cm) compared with the barefoot group (P < .05), and despite the lack of statistical significance, the medium-heel group showed lower values of RVF compared with the two high-heel groups. The EF parameter followed the opposite tendency, showing higher values for the barefoot group compared with the other three groups (P < .05). Values for VFI were similar in the three situations evaluated. Conclusions: High heels reduce muscle pump function, as demonstrated by reduced EF and increased RVF values. The continuous use of high heels tends to provoke venous hypertension in the lower limbs and may represent a causal factor of venous disease symptoms. (J Vasc Surg 2012;56:1039-44.)

Potential impacts of polar fronts on sedimentation processes at Abrolhos coral reef (South-West Atlantic Ocean/Brazil)

Several reefs of the world have undergone changes in community due to sedimentation processes. It has been suggested that Abrolhos reefs (Brazil/South-West Atlantic) are subjected to a steady coastal influence, although there is still little information regarding this assumption. In this work, we have analyzed a set of environmental parameters concerning sedimentation characteristics at the Abrolhos reefs, near 18 degrees S-39 degrees W. The analysis included remote sensing, model and in situ data to provide a three-dimensional quantitative description of the processes that influence sediment apportionment to the reefs. Mineralogy and natural radioactivity of sediment trapped at three reef sites in a transect perpendicular to the coastline were used in conjunction with numerical weather prediction model and remote sensing databases. We have observed an increase of around 100% of sediment flux during the summer compared to the winter season. A comparison of regional rainfall regime, sediment plume dynamics and a year-around monitoring of polar fronts trajectories and surface wind showed that the wind-driven resedimentation due to polar front activity is the major contributor to the intensification of sedimentation processes at the offshore area of Abrolhos reefs, despite river runoff from mainland. (C) 2007 Elsevier Ltd. All rights reserved.

Leishmanicidal and cholinesterase inhibiting activities of phenolic compounds of Dimorphandra gardneriana and Platymiscium floribundum, native plants from Caatinga biome

Nos últimos anos, o Ministério da Saúde do Brasil e a Organização Mundial da Saúde tem apoiado a investigação de novas tecnologias que possam contribuir para a vigilância, novos tratamentos e controle da leishmaniose visceral no país. Assim, o objetivo deste trabalho foi isolar compostos de plantas do bioma Caatinga, e investigar a toxicidade destes compostos contra as formas promastigotas e amastigotas de Leishmania infantum chagasi, principal parasita responsável pela leishmaniose visceral na América do Sul, e avaliar a sua capacidade para inibir a enzima acetil-colinesterase (AChE). Após a exposição aos compostos em estudo, foram realizados testes utilizando a forma promastigota que expressa luciferase e ELISA in situ para medir a viabilidade das formas promastigotas e amastigota, respectivamente. O ensaio colorimétrico MTT foi realizado para determinar a toxicidade destas substâncias utilizando células monocíticas murina RAW 264.7. Todos os compostos foram testados in vitro para as sua propriedade anti-colinesterásica. Um cumarina, escoparona, foi isolada a partir de hastes de Platymiscium floribundum, e os flavonóides, rutina e quercetina, foram isolados a partir de grãos de Dimorphandra gardneriana. Estes compostos foram purificados, utilizando cromatografia em coluna gel eluída com solventes orgânicos em misturas de polaridade crescente, e identificados por análise espectral. Nos ensaios leishmanicidas, os compostos fenólicos mostraram eficácia contra as formas extracelulares promastigotas, com EC50 para escoporona de 21.4µg/mL e para quercetina e rutina 26 e 30.3µg/mL, respectivamente. Os flavonóides apresentaram resultados comparáveis à droga controle, a anfotericina B, contra as formas amastigotas com EC50 para quercetina e rutina de 10.6 e 43.3µg/mL, respectivamente. Os compostos inibiram a enzima AChE com halos de inibição variando de 0,8 a 0,6cm, indicando um possível mecanismo de ação para a atividade leishmanicida.

Safety and efficacy of gemcitabine plus cisplatin combination in pretreated metastatic breast cancer patients

Metastatic breast cancers (MBC) previously treated with anthracyclines (A) and taxanes (T) have a complicated management. Gemcitabine (G)-cisplatin (C) combinations have been used as synergistic salvage therapy in MBC and are considered as another option for patients with important symptoms and aggressive visceral disease. We analyzed the safety and efficacy of GC in AT-pretreated MBC, as well as overall survival (OS) and time to progression (TTP). Forty-nine subjects received IV G 750 mg/m(2) and C 30 mg/m(2), both d1 and d8 every 3 weeks. Response evaluation was performed every second cycle and in the end of treatment. GC protocol was the first-line palliative chemotherapy in half of the cases, and median number of cycles/patient were 4(2-12). Lung (75.5%) was the most frequent site of metastasis. Most of the patients related clinical improvement with chemotherapy with minimal/mild tolerable collateral effects in 85.7% of cases. Following 34 months, mean OS/TTP was 13.12/6.6 months. Objective-responded patients (40.3%) were statistically associated with the improvement in symptoms after CT (P < 0.01), and OS was directly correlated with chemotherapy response (P < 0.01). HER-2 overexpression was a prognostic factor with reduced OS (P = 0.01). GC protocol was effective and tolerable in objective-responded patients.

Metabolic assessment of elderly men with urolithiasis

OBJECTIVE: To assess the presence of metabolic disorders in elderly men with urolithiasis. METHODS: We performed a case-control study. The inclusion criteria were as follows: (1) men older than 60 years of age and either (2) antecedent renal colic or an incidental diagnosis of urinary lithiasis after age 60 (case arm) or (3) no antecedent renal colic or incidental diagnosis of urolithiasis (control arm). Each individual underwent an interview, and those who were selected underwent all clinical protocol examinations: serum levels of total and ionized calcium, uric acid, phosphorus, glucose, urea, creatinine and parathyroid hormone, urine culture, and analysis of 24-hour urine samples (levels of calcium, citrate, creatinine, uric acid and sodium, pH and urine volume). Each case arm patient underwent two complete metabolic urinary investigations, whereas each control arm individual underwent one examination. ClinicalTrials.gov: NCT01246531. RESULTS: A total of 51 subjects completed the clinical investigation: 25 in the case arm and 26 in the control arm. In total, 56% of the case arm patients had hypocitraturia (vs. 15.4% in the control arm; p = 0.002). Hypernatriuria was detected in 64% of the case arm patients and in 30.8% of the controls (p = 0.017). CONCLUSION: Hypocitraturia and hypernatriuria are the main metabolic disorders in elderly men with urolithiasis.

Effect of a rocker non-heeled shoe on EMG and ground reaction forces during gait without previous training

Unstable shoes have been designed to promote "natural instability" and during walking they should simulate barefoot gait, enhancing muscle activity and, thus, attributing an advantage over regular tennis shoes. Recent studies showed that, after special training on the appropriate walking pattern, the use of the Masai Barefoot Technology (MBT) shoe increases muscle activation during walking. Our study presents a comparison of muscle activity as well as horizontal and vertical forces during gait with the MBT, a standard tennis shoe and barefoot walking of healthy individuals without previous training. These variables were compared in 25 female subjects and gait conditions were compared using ANOVA repeated measures (effect size:0.25). Walking with the MBT shoe in this non-instructed condition produced higher vertical forces (first vertical peak and weight acceptance rate) than walking with a standard shoe or walking barefoot, which suggests an increase in the loads received by the musculoskeletal system, especially at heel strike. Walking with the MBT shoe did not increase muscle activity when compared to walking with the standard shoe. The barefoot condition was more effective than the MBT shoe at enhancing muscle activation. Therefore, in healthy individuals, no advantage was found in using the MBT over a standard tennis shoe without a special training period. Further studies using the MBT without any instruction over a longer period are needed to evaluate if the higher loads observed in the present study would return to their baseline values after a period of adaptation, and if the muscle activity would increase over time. (C) 2012 Elsevier B.V. All rights reserved.

Interactions between 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid and gamma-Al2O3 (100) surface calculated by density functional theory

The main aim of this work is to investigate the 1-butyl-3-methylimidazolium tetrafluoroborate ([C4C1Im]+[BF4]-) ionic liquid (IL) adsorption on the gamma-Al2O3 (100) by density functional theory calculations to try to rationalize the adsorption as an electrostatic phenomenon. Optimized geometries and interaction energies of IL one-monolayer on the gamma-Al2O3 were obtained on high surface coverage (one cationanion pair per 94.96 nm2). A study of dispersion force was made to estimate its contribution to the adsorption. Overall, the process is ruled by electrostatic interaction between ions and surface. Adsorption of the anion [BF4]- and cation [C4C1Im]+ was also studied by Bader charge analysis and charge density difference for supported and unsupported situations. It is suggested that the IL ions have their charges maintained with significant anion cloud polarization inward to the acid aluminum sites. (c) 2012 Wiley Periodicals, Inc.

Evaluation of the flexural strength and elastic modulus of resins used for temporary restorations reinforced with particulate glass fibre

Objective: The flexural strength and the elastic modulus of acrylic resins, Dencor, Duralay and Trim Plus II, were evaluated with and without the addition of silanised glass fibre. Materials and methods: To evaluate the flexural strength and elastic modulus, 60 test specimens were fabricated with the addition of 10% ground silanised glass fibres for the experimental group, and 60 without the incorporation of fibres, for the control group, with 20 test specimens being made of each commercial brand of resin (Dencor, Duralay and Trim Plus II) for the control group and experimental group. After the test specimens had been completed, the flexural strength and elastic modulus tests were performed in a universal testing device, using the three-point bending test. For the specimens without fibres the One-Way Analysis of Variance and the complementary Tukey test were used, and for those with fibres it was not normal, so that the non-parametric Mann-Whitney test was applied. Results: For the flexural strength test, there was no statistical difference (p > 0.05) between each commercial brand of resin without fibres [Duralay 84.32(+/- 8.54), Trim plus 85.39(+/- 6.74), Dencor 96.70(+/- 6.52)] and with fibres (Duralay 87.18, Trim plus 88.33, Dencor 98.10). However, for the elastic modulus, there was statistical difference (p > 0.01) between each commercial brand of resin without fibres [Duralay 2380.64 (+/- 168.60), Trim plus 2740.37(+/- 311.74), Dencor 2595.42(+/- 261.22)] and with fibres (Duralay 3750.42, Trim plus 3188.80, Dencor 3400.75). Conclusion: The result showed that the incorporation of fibre did not interfere in the flexural strength values, but it increased the values for the elastic modulus.

Joint loading decreased by inexpensive and minimalist footwear in elderly women with knee osteoarthritis during stair descent

Objective Previous studies indicate that flexible footwear, which mimics the biomechanics of walking barefoot, results in decreased knee loads in patients with knee osteoarthritis (OA) during walking. However, the effect of flexible footwear on other activities of daily living, such as descending stairs, remains unclear. Our objective was to evaluate the influence of inexpensive and minimalist footwear (Moleca) on knee adduction moment (KAM) during stair descent of elderly women with and without knee OA. Methods. Thirty-four elderly women were equally divided into an OA group and a control group (CG). Stair descent was evaluated in barefoot condition, while wearing the Moleca, and while wearing heeled shoes. Kinematics and ground reaction forces were measured to calculate KAM by using inverse dynamics. Results. The OA group experienced a higher KAM during midstance under the barefoot condition (233.3%; P = 0.028), the Moleca (379.2%; P = 0.004), and heeled shoes (217.6%; P = 0.007). The OA group had a similar knee load during early, mid, and late stance with the Moleca compared with the barefoot condition. Heeled shoes increased the knee loads during the early-stance (versus barefoot [16.7%; P < 0.001] and versus the Moleca [15.5%; P < 0.001]), midstance (versus barefoot [8.6%; P = 0.014] and versus the Moleca [9.5%; P = 0.010]), and late-stance phase (versus barefoot [10.6%; P = 0.003] and versus the Moleca [9.2%; P < 0.001]). In the CG, the Moleca produced a knee load similar to the barefoot condition only during the early-stance phase. Conclusion. Besides the general foot protection, the inexpensive and minimalist footwear contributes to decreasing knee loads in elderly women with OA during stair descent. The loads are similar to the barefoot condition and effectively decreased when compared with heeled shoes.

Physical-chemical and microbiological changes in Cerrado Soil under differing sugarcane harvest management systems

Background: Sugarcane cultivation plays an important role in Brazilian economy, and it is expanding fast, mainly due to the increasing demand for ethanol production. In order to understand the impact of sugarcane cultivation and management, we studied sugarcane under different management regimes (pre-harvest burn and mechanical, unburnt harvest, or green cane), next to a control treatment with native vegetation. The soil bacterial community structure (including an evaluation of the diversity of the ammonia oxidizing (amoA) and denitrifying (nirK) genes), greenhouse gas flow and several soil physicochemical properties were evaluated. Results: Our results indicate that sugarcane cultivation in this region resulted in changes in several soil properties. Moreover, such changes are reflected in the soil microbiota. No significant influence of soil management on greenhouse gas fluxes was found. However, we did find a relationship between the biological changes and the dynamics of soil nutrients. In particular, the burnt cane and green cane treatments had distinct modifications. There were significant differences in the structure of the total bacterial, the ammonia oxidizing and the denitrifying bacterial communities, being that these groups responded differently to the changes in the soil. A combination of physical and chemical factors was correlated to the changes in the structures of the total bacterial communities of the soil. The changes in the structures of the functional groups follow a different pattern than the physicochemical variables. The latter might indicate a strong influence of interactions among different bacterial groups in the N cycle, emphasizing the importance of biological factors in the structuring of these communities. Conclusion: Sugarcane land use significantly impacted the structure of total selected soil bacterial communities and ammonia oxidizing and denitrifier gene diversities in a Cerrado field site in Central Brazil. A high impact of land use was observed in soil under the common burnt cane management. The green cane soil also presented different profiles compared to the control soil, but to at a lesser degree.

Cardiovascular effects of partial sleep deprivation in healthy volunteers

Dettoni JL, Consolim-Colombo FM, Drager LF, Rubira MC, de Souza SB, Irigoyen MC, Mostarda C, Borile S, Krieger EM, Moreno H Jr, Lorenzi-Filho G. Cardiovascular effects of partial sleep deprivation in healthy volunteers. J Appl Physiol 113: 232-236, 2012. First published April 26, 2012; doi: 10.1152/japplphysiol.01604.2011.-Sleep deprivation is common in Western societies and is associated with increased cardiovascular morbidity and mortality in epidemiological studies. However, the effects of partial sleep deprivation on the cardiovascular system are poorly understood. In the present study, we evaluated 13 healthy male volunteers (age: 31 +/- 2 yr) monitoring sleep diary and wrist actigraphy during their daily routine for 12 nights. The subjects were randomized and crossover to 5 nights of control sleep (>7 h) or 5 nights of partial sleep deprivation (<5 h), interposed by 2 nights of unrestricted sleep. At the end of control and partial sleep deprivation periods, heart rate variability (HRV), blood pressure variability (BPV), serum norepinephrine, and venous endothelial function (dorsal hand vein technique) were measured at rest in a supine position. The subjects slept 8.0 +/- 0.5 and 4.5 +/- 0.3 h during control and partial sleep deprivation periods, respectively (P < 0.01). Compared with control, sleep deprivation caused significant increase in sympathetic activity as evidenced by increase in percent low-frequency (50 +/- 15 vs. 59 +/- 8) and a decrease in percent high-frequency (50 +/- 10 vs. 41 +/- 8) components of HRV, increase in low-frequency band of BPV, and increase in serum norepinephrine (119 +/- 46 vs. 162 +/- 58 ng/ml), as well as a reduction in maximum endothelial dependent venodilatation (100 +/- 22 vs. 41 +/- 20%; P < 0.05 for all comparisons). In conclusion, 5 nights of partial sleep deprivation is sufficient to cause significant increase in sympathetic activity and venous endothelial dysfunction. These results may help to explain the association between short sleep and increased cardiovascular risk in epidemiological studies.

In vitro action of antiparasitic drugs, especially artesunate, against Toxoplasma gondii

Introduction: Toxoplasmosis is usually a benign infection, except in the event of ocular, central nervous system (CNS), or congenital disease and particularly when the patient is immunocompromised. Treatment consists of drugs that frequently cause adverse effects; thus, newer, more effective drugs are needed. In this study, the possible activity of artesunate, a drug successfully being used for the treatment of malaria, on Toxoplasma gondii growth in cell culture is evaluated and compared with the action of drugs that are already being used against this parasite. Methods: LLC-MK2 cells were cultivated in RPMI medium, kept in disposable plastic bottles, and incubated at 36 degrees C with 5% CO2. Tachyzoites of the RH strain were used. The following drugs were tested: artesunate, cotrimoxazole, pentamidine, pyrimethamine, quinine, and trimethoprim. The effects of these drugs on tachyzoites and LLC-MK2 cells were analyzed using nonlinear regression analysis with Prism 3.0 software. Results: Artesunate showed a mean tachyzoite inhibitory concentration (IC50) of 0.075 mu M and an LLC MK2 toxicity of 2.003 mu M. Pyrimethamine was effective at an IC50 of 0.482 mu M and a toxicity of 11.178 mu M. Trimethoprim alone was effective against the in vitro parasite. Cotrimoxazole also was effective against the parasite but at higher concentrations than those observed for artesunate and pyrimethamine. Pentamidine and quinine had no inhibitory effect over tachyzoites. Conclusions: Artesunate is proven in vitro to be a useful alternative for the treatment of toxoplasmosis, implying a subsequent in vivo effect and suggesting the mechanism of this drug against the parasite.

String Quartet n degrees 02 by Villa-Lobos: a dialogue with the cyclic form of Franck, Debussy and Ravel

This article investigates Villa-Lobos's String Quartet n degrees 02, an early work by this composer, written according cyclic sonata principles, as developed by Cesar Franck and systematized by Vincent d'Indy. Another important source are the string quartets composed by Franck (1889), Debussy (1893) and Ravel (1903), which possibly served as compositional models to Villa-Lobos. In this light, the themes of the Exposition in the first movement were analyzed and this procedure reveals some harmonic and rhythmic aspects throughout all the other movements.

Solar-Terrestrial Signal Record in Tree Ring Width Time Series from Brazil

This work investigates the behavior of the sunspot number and Southern Oscillation Index (SOI) signal recorded in the tree ring time series for three different locations in Brazil: Humaita in Amaznia State, Porto Ferreira in So Paulo State, and Passo Fundo in Rio Grande do Sul State, using wavelet and cross-wavelet analysis techniques. The wavelet spectra of tree ring time series showed signs of 11 and 22 years, possibly related to the solar activity, and periods of 2-8 years, possibly related to El Nio events. The cross-wavelet spectra for all tree ring time series from Brazil present a significant response to the 11-year solar cycle in the time interval between 1921 to after 1981. These tree ring time series still have a response to the second harmonic of the solar cycle (5.5 years), but in different time intervals. The cross-wavelet maps also showed that the relationship between the SOI x tree ring time series is more intense, for oscillation in the range of 4-8 years.