Efficiency and bacterial diversity of an improved anaerobic baffled reactor for the remediation of wastewater from alkaline-surfactant-polymer (ASP) flooding technology.

Alkaline-surfactant-polymer (ASP) flooding technology is used to maximize crude oil recovery. However, the extensive use of alkaline materials makes it difficult to treat the water used. Here, an improved multi-zone anaerobic baffled reactor (ABR) using FeSO4 as electron acceptor was employed to treat the wastewater from ASP flooding technology, and the effects on major pollutants (hydrolyzed polyacrylamide, petroleum substances, surfactants suspended solids) and associated parameters (chemical oxygen demand, viscosity) were evaluated. Gas chromatography-mass spectrometry (GC-MS) was used to follow the degradation and evolution of organic compounds while high-throughput DNA sequencing was used to determine the bacterial diversity in the ABR. The results obtained after 90 d of operation showed decreases in all parameters measured and the highest mean removal rates were obtained for petroleum substances (98.8%) and suspended solids (77.0%). Amounts of petroleum substances in the ABR effluent could meet the requirements of a national standard for oilfield reinjection water. GC-MS analysis showed that a wide range of chemicals (e.g. aromatic hydrocarbons, esters, alcohols, ketones) could be sequentially removed from the influent by each zone of ABR. The high-throughput DNA sequencing showed that the bacteria Micropruina, Saccharibacteria and Synergistaceae were involved in the degradation of pollutants in the anaerobic and anoxic reaction zones, while Rhodobacteraceae and Aliihoeflea were the main functional microorganisms in the aerobic reaction zones. The results demonstrated that the improved ABR reactor had the potential for the treatment of wastewater from ASP flooding technology.

Energetics contribution during no-gi Brazilian jiu jitsu sparring and its association with regional body composition.

We used measurements of metabolic perturbation obtained after sparring to estimate energetics contribution during no-gi Brazilian jiu-jitsu. Ten advanced grapplers performed two six-minute sparring bouts separated by 24 hours. Kinetics of recovery rate of oxygen uptake was modelled and post-combat-sparring blood-lactate concentration measured to estimate oxygen equivalents for phospholytic and glycolytic components of anaerobic energetics, respectively. Linear regression was used to estimate end-combat-sparring rate of oxygen uptake. Regional and whole-body composition were assessed using dual X-ray absorptiometry with associations between these measurements and energy turnover explored using Pearson's correlation coefficient (significance, P < 0.05). Estimated oxygen equivalents for phospholytic and glycolytic contributions to anaerobic metabolism were 16.9 ± 8.4 (~28%) and 44.6 ± 13.5 (~72%) mL∙kg-1, respectively. Estimated end-exercise rate of oxygen uptake was 44.2 ± 7.0 mL∙kg-1∙min-1. Trunk lean mass was positively correlated with both total anaerobic and glycolytic-specific energetics (total, R = 0.645, p = 0.044; glycolytic, R = 0.692, p = 0.027) and negatively correlated with end-exercise rate of oxygen uptake (R = -0.650, p = 0.042). There were no correlations for any measurement of body composition and phospholytic-specific energetics. Six minutes of no-gi Brazilian jiu-jitsu sparring involves high relative contribution from the glycolytic component to total anaerobic energy provision and the link between this energetics profile and trunk lean mass is consistent with the predominance of ground-based combat that is unique for this combat sport. Training programs for Brazilian jiu-jitsu practitioners should be designed with consideration given to these specific energetics characteristics.

Detoxification of Ciprofloxacin in an Anaerobic Bioprocess Supplemented with Magnetic Carbon Nanotubes: Contribution of Adsorption and Biodegradation Mechanisms.

In anaerobic bioreactors, the electrons produced during the oxidation of organic matter can potentially be used for the biological reduction of pharmaceuticals in wastewaters. Common electron transfer limitations benefit from the acceleration of reactions through utilization of redox mediators (RM). This work explores the potential of carbon nanomaterials (CNM) as RM on the anaerobic removal of ciprofloxacin (CIP). Pristine and tailored carbon nanotubes (CNT) were first tested for chemical reduction of CIP, and pristine CNT was found as the best material, so it was further utilized in biological anaerobic assays with anaerobic granular sludge (GS). In addition, magnetic CNT were prepared and also tested in biological assays, as they are easier to be recovered and reused. In biological tests with CNM, approximately 99% CIP removal was achieved, and the reaction rates increased ≈1.5-fold relatively to the control without CNM. In these experiments, CIP adsorption onto GS and CNM was above 90%. Despite, after applying three successive cycles of CIP addition, the catalytic properties of magnetic CNT were maintained while adsorption decreased to 29 ± 3.2%, as the result of CNM overload by CIP. The results suggest the combined occurrence of different mechanisms for CIP removal: adsorption on GS and/or CNM, and biological reduction or oxidation, which can be accelerated by the presence of CNM. After biological treatment with CNM, toxicity towards Vibrio fischeri was evaluated, resulting in ≈ 46% detoxification of CIP solution, showing the advantages of combining biological treatment with CNM for CIP removal.

Short-term co-ingestion of creatine and sodium bicarbonate improves anaerobic performance in trained taekwondo athletes.

BACKGROUND: Creatine (CR) and sodium bicarbonate (SB) alone improve anaerobic performance. However, the ergogenic effects of CR and SB co-ingestion on taekwondo anaerobic performance remains unknown. METHODS: Forty trained taekwondo athletes (21 ± 1 y.; 180.5 ± 7.3 cm; 72.7 ± 8.6 kg) were randomized to: (i) CR and SB (CR + SB; 20 g of CR+ 0.5 g·kg- 1·d- 1 of SB), (ii) CR, (iii) SB, (iv) placebo (PLA), or (v) control (CON) for 5 days. Before and after supplementation, participants completed 3 bouts of a Taekwondo Anaerobic Intermittent Kick Test (TAIKT) to determine changes in peak power (PP), mean power (MP), and fatigue index (FI). Blood lactate (BL) was measured before, immediately following, and 3 min post-TAIKT. RESULTS: PP and MP increased over time (P < 0.05) following CR + SB, CR, and SB ingestion, with no changes in the PLA or CON groups. There was a greater increase over time in MP following CR + SB (Absolute Δ: 1.15 ± 0.28 W∙kg67) compared to CR (Absolute Δ: 0.43 ± 0.33 W∙kg67; P < 0.001) and SB (Absolute Δ: 0.73 ± 0.24 W∙kg67; P = 0.03). There were no significant time and condition effect for FI (P > 0.05). BL increased following exercise across all groups; however, CR + SB and SB post-exercise BL was lower compared to CR, PLA, and CON (P < 0.05). CONCLUSION: Short-term CR and SB alone enhance TAIKT performance in trained taekwondo athletes. Co-ingestion of CR and SB augments MP compared to CR and SB alone, with similar PP improvements.

The effect of citrus flavonoid extract supplementation on anaerobic capacity in moderately trained athletes: a randomized controlled trial.

BACKGROUND: Nutritional supplementation is commonly used by athletes to improve their exercise performance. Previous studies demonstrated that citrus flavonoid extract (CFE) supplementation may be an effective strategy to improve exercise performance in male athletes. Yet, no conclusive research has been performed to investigate the effect of chronic CFE supplementation on high-intensity exercise performance under anaerobic conditions. Therefore, the aim of the study was to assess whether CFE supplementation in daily dosages of 400 and 500 mg for a period of 4 and 8 weeks improves anaerobic exercise capacity. METHODS: A randomized, double-blind, placebo controlled, parallel clinical study was conducted in 92 moderately trained healthy men and women. Subjects were randomized to receive 400 mg of CFE (n = 30), 500 mg of CFE (n = 31) or placebo (n = 31) daily, for 8 consecutive weeks. The Wingate anaerobic test was used to assess anaerobic exercise capacity and power output at baseline, after 4 weeks and after 8 weeks. RESULTS: After 4 weeks supplementation, average power output significantly increased in the 400 mg group (Estimated difference [ED] = 38.2 W [18.0, 58.3]; p < 0.001; effect size [ES] = 0.27) and in the 500 mg group (ED = 21.2 W [0.91, 41.4]; p = 0.041; ES = 0.15) compared to placebo. The 5 s peak power output was also increased in the 400 mg group (ED = 53.6 [9.96, 97.2]; p = 0.017; ES = 0.25) after 4 weeks compared to placebo. After 8 weeks of supplementation, average power output was significantly improved in the group receiving 400 mg of CFE (ED = 31.6 [8.33, 54.8]; p = 0.008; ES = 0.22) compared to placebo. CONCLUSION: These results demonstrate that CFE supplementation improved anaerobic capacity and peak power during high intensity exercise in moderately trained individuals. Further research is needed to identify the underlying mechanisms that are affected by CFE supplementation. TRIAL REGISTRATION: ClinicalTrials.gov ( NCT03044444 ). Registered 7 February 2017.

Effects of Beta-Alanine Supplementation on Physical Performance in Aerobic-Anaerobic Transition Zones: A Systematic Review and Meta-Analysis.

Beta-alanine supplementation (BA) has a positive impact on physical performance. However, evidence showing a benefit of this amino acid in aerobic-anaerobic transition zones is scarce and the results controversial. The aim of this systematic review and meta-analysis is to analyze the effects of BA supplementation on physical performance in aerobic-anaerobic transition zones. At the same time, the effect of different dosages and durations of BA supplementation were identified. The search was designed in accordance with the PRISMA® guidelines for systematic reviews and meta-analyses and performed in Web of Science (WOS), Scopus, SPORTDiscus, PubMed, and MEDLINE between 2010 and 2020. The methodological quality and risk of bias were evaluated with the Cochrane Collaboration tool. The main variables were the Time Trial Test (TTT) and Time to Exhaustion (TTE) tests, the latter separated into the Limited Time Test (LTT) and Limited Distance Test (LDT). The analysis was carried out with a pooled standardized mean difference (SMD) through Hedges' g test (95% CI). Nineteen studies were included in the systematic review and meta-analysis, revealing a small effect for time in the TTT (SMD, -0.36; 95% CI, -0.87-0.16; I2 = 59%; p = 0.010), a small effect for LTT (SMD, 0.25; 95% CI, -0.01-0.51; I2 = 0%; p = 0.53), and a large effect for LDT (SMD, 4.27; 95% CI, -0.25-8.79; I2 = 94%; p = 0.00001). BA supplementation showed small effects on physical performance in aerobic-anaerobic transition zones. Evidence on acute supplementation is scarce (one study); therefore, exploration of acute supplementation with different dosages and formats on physical performance in aerobic-anaerobic transition zones is needed.

Flavagline synthetic derivative induces senescence in glioblastoma cancer cells without being toxic to healthy astrocytes.

Glioblastoma (GBM) is one of the most aggressive types of cancer, which begins within the brain. It is the most invasive type of glioma developed from astrocytes. Until today, Temozolomide (TMZ) is the only standard chemotherapy for patients with GBM. Even though chemotherapy extends the survival of patients, there are many undesirable side effects, and most cases show resistance to TMZ. FL3 is a synthetic flavagline which displays potent anticancer activities, and is known to inhibit cell proliferation, by provoking cell cycle arrest, and leads to apoptosis in a lot of cancer cell lines. However, the effect of FL3 in glioblastoma cancer cells has not yet been examined. Hypoxia is a major problem for patients with GBM, resulting in tumor resistance and aggressiveness. In this study, we explore the effect of FL3 in glioblastoma cells under normoxia and hypoxia conditions. Our results clearly indicate that this synthetic flavagline inhibits cell proliferation and induced senescence in glioblastoma cells cultured under both conditions. In addition, FL3 treatment had no effect on human brain astrocytes. These findings support the notion that the FL3 molecule could be used in combination with other chemotherapeutic agents or other therapies in glioblastoma treatments.

Anaerobic microbial communities and their potential for bioenergy production in heavily biodegraded petroleum reservoirs.

Most of the oil in low temperature, non-uplifted reservoirs is biodegraded due to millions of years of microbial activity, including via methanogenesis from crude oil. To evaluate stimulating additional methanogenesis in already heavily biodegraded oil reservoirs, oil sands samples were amended with nutrients and electron acceptors, but oil sands bitumen was the only organic substrate. Methane production was monitored for over 3000 days. Methanogenesis was observed in duplicate microcosms that were unamended, amended with sulfate or that were initially oxic, however methanogenesis was not observed in nitrate-amended controls. The highest rate of methane production was 0.15 µmol CH4 g-1 oil d-1 , orders of magnitude lower than other reports of methanogenesis from lighter crude oils. Methanogenic Archaea and several potential syntrophic bacterial partners were detected following the incubations. GC-MS and FTICR-MS revealed no significant bitumen alteration for any specific compound or compound class, suggesting that the very slow methanogenesis observed was coupled to bitumen biodegradation in an unspecific manner. After 3000 days, methanogenic communities were amended with benzoate resulting in methanogenesis rates that were 110-fold greater. This suggests that oil-to-methane conversion is limited by the recalcitrant nature of oil sands bitumen, not the microbial communities resident in heavy oil reservoirs.

Selecting for lactic acid producing and utilising bacteria in anaerobic enrichment cultures.

Lactic acid-producing bacteria are important in many fermentations, such as the production of biobased plastics. Insight in the competitive advantage of lactic acid bacteria over other fermentative bacteria in a mixed culture enables ecology-based process design and can aid the development of sustainable and energy-efficient bioprocesses. Here we demonstrate the enrichment of lactic acid bacteria in a controlled sequencing batch bioreactor environment using a glucose-based medium supplemented with peptides and B vitamins. A mineral medium enrichment operated in parallel was dominated by Ethanoligenens species and fermented glucose to acetate, butyrate and hydrogen. The complex medium enrichment was populated by Lactococcus, Lactobacillus and Megasphaera species and showed a product spectrum of acetate, ethanol, propionate, butyrate and valerate. An intermediate peak of lactate was observed, showing the simultaneous production and consumption of lactate, which is of concern for lactic acid production purposes. This study underlines that the competitive advantage for lactic acid-producing bacteria primarily lies in their ability to attain a high biomass specific uptake rate of glucose, which was two times higher for the complex medium enrichment when compared to the mineral medium enrichment. The competitive advantage of lactic acid production in rich media can be explained using a resource allocation theory for microbial growth processes.

Theaflavic acid from black tea protects PC12 cells against ROS-mediated mitochondrial apoptosis induced by OGD/R via activating Nrf2/ARE signaling pathway.

Cerebral ischemic stroke is a severe disease afflicting people worldwide. Phytochemicals play a pivotal role in the discovery of novel therapeutic approaches for the prevention of ischemic stroke. In our continual search for bioactive natural products for the treatment of ischemic stroke, we have evaluated the protective effects of theaflavic acid (TFA) from black tea using PC12 cells injured by oxygen and glucose deprivation/restoration (OGD/R), and investigated the possible mechanisms. The results showed that TFA can protect PC12 cells against OGD/R through increasing cell viability and decreasing intracellular lactate dehydrogenase (LDH) release. Further investigations found that TFA could inhibit the overproduction of intracellular reactive oxygen species (ROS), reduce malondialdehyde content, and elevate superoxide dismutase activity, which implied that TFA suppresses oxidative stress in PC12 cells induced by OGD/R. In addition, overload of intracellular calcium and collapse of the mitochondrial membrane potential were improved in the presence of TFA, and the activity of caspase-3 was significantly reduced by TFA. Western blot analysis showed that the expression of Bcl-2 was up-regulated while Bax was down-regulated. Therefore, it can be concluded that TFA can inhibit mitochondria-dependent apoptosis of PC12 cells induced by OGD/R. In addition, activation of the nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response elements (ARE) signaling pathway was explored to elucidate the mechanism by which TFA inhibits ROS-mediated apoptosis in PC12 cells. The results revealed that TFA promoted the translocation of Nrf2 into nuclei, enhanced the transcriptional activity of ARE, and up-regulated expression of downstream HO-1, which indicates that the Nrf2/ARE signaling pathway is involved in the protection by TFA of PC12 cells injured by OGD/R.

Operation mode of a step-feed anoxic/oxic process with distribution of carbon source from anaerobic zone on nutrient removal and microbial properties.

This study investigated the operation mode of a step-feed anoxic/oxic (A/O) process with distribution of the carbon source from the anaerobic zone in terms of the treatment effects on sewage with low carbon and high nitrogen and phosphorus. After seven phases of operation, an optimal flow distribution ratio of 75%:25% was obtained from the anaerobic zone, and the concentrations of chemical oxygen demand, ammonia nitrogen, total nitrogen, and total phosphorous in the effluent were 20.8, 0.64, 14.2, and 0.89 mg/L, respectively. The presence of an internal reflux system in the deaeration zone improved the treatment. 16S rRNA high-throughput sequencing revealed that the microbial communities in aerobic zone I(O1) of the first-step A/O sludge were different from those in aerobic zone I (O2) of the second-step A/O sludge, whereas microbial communities of the seed sludge were similar to those in O2 of the second-step A/O sludge. The richness and diversity of microbial communities in O1 of the first-step A/O sludge samples were higher than those in O2 of the second-step A/O and seed sludge. At the optimal flow distribution ratio, the microbial abundance and treatment removal efficiency were the highest.

Novel red fluorescence protein based microplate assay for drug screening against dormant Mycobacterium tuberculosis by using paraffin.

The hypoxia model of dormancy is widely used in drug screening programs to identify novel inhibitors against latent Mycobacterium tuberculosis disease. In earlier reported microplate assays, hypoxia was maintained by either sealing the microplate or shifting in an anaerobic chamber to develop dormant phenotype. In these assays, inhibitors were added during inoculation, which mainly represents the active stage inhibitors instead of the dormant ones. Herein, the culture was covered with paraffin to develop hypoxia condition and consequently providing the advantage of adding compounds at any stage during incubation of 96-well plate. The stable expression of the red fluorescent protein in the bacilli under both actively growing as well as dormant conditions also facilitate the reliable estimation of growth and inhibition kinetics of bacilli in medium. Furthermore, S/N ratio and Z' factor of this assay were found to be > 27 and 0.91-0.94 respectively, which confirm the robustness of the protocol. This newly developed drug-screening assay offers an easy, inexpensive, safe and high throughput-screening tool to search novel antitubercular inhibitors against both active and dormant bacilli. The red fluorescent H37Ra strain is a suitable surrogate for the more virulent H37Rv strain, and thus this effort will help in combating latent tuberculosis.

Strong antimicrobial activity of xanthohumol and other derivatives from hops (Humulus lupulus L.) on gut anaerobic bacteria.

Anaerobic bacteria, such as Bacteroides fragilis or Clostridium perfringens, are part of indigenous human flora. However, Clostridium difficile represents also an important causative agent of nosocomial infectious antibiotic-associated diarrhoea. Treatment of C. difficile infection is problematic, making it imperative to search for new compounds with antimicrobial properties. Hops (Humulus lupulus L.) contain substances with antibacterial properties. We tested antimicrobial activity of purified hop constituents humulone, lupulone and xanthohumol against anaerobic bacteria. The antimicrobial activity was established against B. fragilis, C. perfringens and C. difficile strains according to standard testing protocols (CLSI, EUCAST), and the minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBC) were calculated. All C. difficile strains were toxigenic and clinically relevant, as they were isolated from patients with diarrhoea. Strongest antimicrobial effects were observed with xanthohumol showing MIC and MBC values of 15-107 µg/mL, which are close to those of conventional antibiotics in the strains of bacteria with increased resistance. Slightly higher MIC and MBC values were obtained with lupulone followed by higher values of humulone. Our study, thus, shows a potential of purified hop compounds, especially xanthohumol, as alternatives for treatment of infections caused by select anaerobic bacteria, namely nosocomial diarrhoea caused by resistant strains.

[Production of Methane in Anaerobic Digestion of Organic Waste of Vegetable Processing Facilities].

The article concerns converting waste from vegetable processing facilities into methane in anaerobic reactors with a small amount of inoculum (8.4%). Anaerobic digestion of vegetable waste with a high content of organic acids and carbohydrates makes it possible to achieve a methanogenesis productivity of 273­436 L CH4/kg of volatile solidis, which is comparable to or higher than the productivity of such reactors in the world (according to the literature). The contents of ammonia nitrogen and soluble phosphorus in the form of on undiluted substrate basis in the digested vegetable wastes ranged from 3.39 to 5.06 and from 0.78 to 1.03 g/L respectively. Thus, mineralized vegetable waste can be used as an organic fertilizer with a high nutrient content. The results show the feasibility of the technology of conversion of organic waste from vegetable processing facilities into methane and organic fertilizer in anaerobic fermenters (digesters).

Cinnamon (Cinnamomum sp.) inclusion in diets for Nile tilapia submitted to acute hypoxic stress.

The aim of this study was to evaluate the possible effects of diets supplemented with probiotics and different cinnamon levels (powder and essential oil) on immunological parameters of Nile tilapia after being subjected to acute stress by hypoxia. Three hundred and thirty juvenile male tilapia fish (66.08 ± 2.79 g) were distributed in 30 tanks of 100 L capacity (11/cage) with a water recirculation system. The animals were fed for 71 days with diets containing extruded cinnamon powder at different levels (0.5, 1, 1.5, 2%), cinnamon essential oil (0.05, 0.1, 0.15; 0.2%) and probiotics (0.4%), all in triplicate. At the end of the experiment, the fish (200.36 ± 19.88 g) of the different groups were subjected to stress by hypoxia. Hypoxia was achieved by capturing the animals with a net, keeping them out of the water for three minutes, and then sampling the blood 30 min after the procedure to determine the levels of cortisol, glucose, haematocrit, lysozyme, bactericidal index, total protein, and its fractions. The animals kept blood homeostasis after hypoxic stress. Diet supplementation with 0.5% cinnamon powder improved the fish immune response, since it resulted in an increase of 0.5% in γ-globulin level. Administration of 0.15% cinnamon essential oil resulted in an increase of α1 and α2-globulins, which may be reflected in increased lipid content of the carcass and the hepatosomatic index. More studies are necessary to better understand the effects of these additives for fish immunity.

Fed-batch cultivation of Arthrospira and Chlorella in ammonia-rich wastewater: Optimization of nutrient removal and biomass production.

In the present work the cyanobacterium Arthrospira platensis and the microalga Chlorella vulgaris were fed-batch cultivated in ammonia-rich wastewater derived from the anaerobic digestion of poultry litter. Aim of the study was to maximize the biomass production along with the nutrient removal aiming to wastewater treatment. Ammonia and phosphorus removals were very high (>95%) for all cultures investigated. Both microorganisms were able to remove volatile fatty acids to an extent of >90%, indicating that they were capable of mixotrophic growth. Chemical oxygen demand and proteins were also removed in various degrees. In contrast, in all cultures carbohydrate concentration was increased. The biochemical composition of the microorganisms varied greatly and was influenced by the indicate that the nutrient availability. A. platensis accumulated carbohydrates (≈ 40%), while C. vulgaris accumulated lipids (≈ 50%), rendering them interesting for biofuel production.

Biogas production within the bioethanol production chain: Use of co-substrates for anaerobic digestion of sugar beet vinasse.

Bioethanol production generates large amounts of vinasse, which is suitable for biogas production. In this study, the anaerobic digestion of sugar beet vinasse was optimised using continuous stirred-tank reactors (CSTR) supplemented either with lime fertiliser or with 3% cow manure. In both reactors, the C/N ratio was adjusted by adding straw. The biochemical methane potential (BMP) of vinasse was 267.4±4.5LCH4kgVS(-1). Due to the low content of macro- and micronutrients and low C/N ratio of vinasse, biogas production failed when vinasse alone was fed to the reactor. When co-substrate was added, biogas production achieved very close to the BMP of vinasse, being 235.7±32.2LCH4kgVS(-1) from the fertiliser supplied reactor and 265.2±26.8LCH4kgVS(-1) in manure supplied reactor at steady state. Anaerobic digestion was the most stable when cow manure was supplied to digestion of vinasse.

Effects of creatine supplementation in taekwondo practitioners.

INTRODUCTION: Taekwondo (TKD) is a combat sport, which has also been proposed as a fitness program, with a strong anaerobic component. Creatine (Cr) supplementation is used to improve both anaerobic exercise performance and body composition. Therefore, Cr supplementation could be beneficial in TKD. AIMS: To determine the effect of Cr supplementation (50 mg/kg body wt) on body composition, anaerobic power and blood chemistry in young male TKD practitioners. METHODS: Ten male TKD practitioners (age [20 ± 2 yr], height [1.69 ± 0.06 m], and mass [67 ± 9.8 kg]) participated in a placebo-controlled, double blind, crossover study. Body composition (DEXA), anaerobic power (Wingate Test), blood lactate and blood chemistry were measured before and after supplementation. Differences between data before and after supplementation were calculated for each treatment (Cr and Placebo) and were compared using the Wilcoxon signed-rank test. RESULTS: Fat mass (kg) decreased after placebo (Mdn [IqR] = -0.75 [-1.44 to 0.03]) and increased following Cr intake (0.17 [-0.77 to 1.13] kg) (Z = 2.191, p < 0.028, r = 0.49). Serum triglyceride concentration (mg/mL) increased after Cr (45.00 [-7.50 to 75.00]) and decrease with placebo (-7.00 [-10.75 to 12.00]) (Z = 2.090, p < 0.037, r = 0.47). No changes were found in others parameters. CONCLUSION: Cr supplementation may increase fat mass and serum triglycerides concentration in young male TKD practitioners without improvement in anaerobic power. Cr supplementation appears to be safe, but athletes should be careful when they want to loss fat.

Introducción: El Taekwondo (TKD) es un arte marcial, que ha sido propuesto también en programas de actividad física, con un fuerte componente anaeróbico. La suplementación con creatina (Cr), utilizada para mejorar el rendimiento deportivo y la composición corporal, puede ser beneficiosa en TKD. Objetivos: Determinar el efecto de la suplementación de Cr sobre la composición corporal, potencia anaeróbica y bioquímica sanguínea en practicantes jóvenes de TKD. Métodos: Diez practicantes varones de TKD (edad [20 ± 2 AÑOs], estatura [1,69 ± 0,06 m], peso [67,0 ± 9,8 kg]) participaron en un ensayo aleatorizado cruzado (grupo control + placebo). Se evaluaron (pre-post suplementación) la composición corporal (DEXA), la potencia anaeróbica (Test de Wingate), el lactato y la bioquímica sanguínea. Se calculó la diferencia entre los valores pre y post ingestión para ambos tratamientos (Cr y placebo) y se compararon las diferencias usando la prueba de signos y rangos de Wilcoxon. Resultados: La masa grasa (kg) disminuyó después del placebo (Mdn [IqR] = -0,75 [-1,44 a 0,03]) mientras que con Cr se elevó significativamente (0,17 [-0,77 a 1,13] kg) (Z = 2,191, p < 0,028, r = 0,49). La concentración sanguínea de triglicéridos (mg/mL) aumentó con Cr (45,00 [- 7,50 a 75,00]) y disminuyó con Placebo (-7,00 [-10,75 a 12,00]) (Z = 2,090, p < 0,037, r = 0,47). No hubo cambios significativos en otros parámetros. Conclusiones: La suplementación con creatina puede incrementar la masa grasa y la concentración sanguínea de triglicéridos en jóvenes practicantes de TKD, sin mejorar la potencia anaerobia. La suplementación parece ser segura, pero es necesario ser cuidadosos cuando se busca disminuir el peso corporal.

Systems analysis of transcription factor activities in environments with stable and dynamic oxygen concentrations.

Understanding gene regulation requires knowledge of changes in transcription factor (TF) activities. Simultaneous direct measurement of numerous TF activities is currently impossible. Nevertheless, statistical approaches to infer TF activities have yielded non-trivial and verifiable predictions for individual TFs. Here, global statistical modelling identifies changes in TF activities from transcript profiles of Escherichia coli growing in stable (fixed oxygen availabilities) and dynamic (changing oxygen availability) environments. A core oxygen-responsive TF network, supplemented by additional TFs acting under specific conditions, was identified. The activities of the cytoplasmic oxygen-responsive TF, FNR, and the membrane-bound terminal oxidases implied that, even on the scale of the bacterial cell, spatial effects significantly influence oxygen-sensing. Several transcripts exhibited asymmetrical patterns of abundance in aerobic to anaerobic and anaerobic to aerobic transitions. One of these transcripts, ndh, encodes a major component of the aerobic respiratory chain and is regulated by oxygen-responsive TFs ArcA and FNR. Kinetic modelling indicated that ArcA and FNR behaviour could not explain the ndh transcript profile, leading to the identification of another TF, PdhR, as the source of the asymmetry. Thus, this approach illustrates how systematic examination of regulatory responses in stable and dynamic environments yields new mechanistic insights into adaptive processes.

Influence of exercise on nutritional requirements.

There is no consensus on the best diet for exercise, as many variables influence it. We propose an approach that is based on the total energy expenditure of exercise and the specific macro- and micronutrients used. di Prampero quantified the impact of intensity and duration on the energy cost of exercise. This can be used to determine the total energy needs and the balance of fats and carbohydrates (CHO). There are metabolic differences between sedentary and trained persons, thus the total energy intake to prevent overfeeding of sedentary persons and underfeeding athletes is important. During submaximal sustained exercise, fat oxidation (FO) plays an important role. This role is diminished and CHO's role increases as exercise intensity increases. At super-maximal exercise intensities, anaerobic glycolysis dominates. In the case of protein and micronutrients, specific recommendations are required. We propose that for submaximal exercise, the balance of CHO and fat favors fat for longer exercise and CHO for shorter exercise, while always maintaining the minimal requirements of each (CHO: 40% and fat: 30%). A case for higher protein (above 15%) as well as creatine supplementation for resistance exercise has been proposed. One may also consider increasing bicarbonate intake for exercise that relies on anaerobic glycolysis, whereas there appears to be little support for antioxidant supplementation. Insuring minimal levels of substrate will prevent exercise intolerance, while increasing some components may increase exercise tolerance.