Study of the Risk of Ankle Injury During Impact on the Ground and Definition of Support Orthoses

This work studies the effect of different orthoses on preventing injuries in the ankle-foot joint. It was carried out using OpenSim and the available ankle-foot musculoskeletal model and AFO orthoses models. The motion situation assessed is related to placing the foot on the ground. It is also analyzed how a passive ankle-foot orthosis, muscles reflexes and muscle coactivation influence the risk of injury, namely during ankle inversion. Results indicate that muscle coactivation and the use of an AFO can reduce injury risk. Thus, an average stiffness AFO is best suited for preventing ankle injuries.info:eu-repo/semantics/publishedVersio

Preliminary study on the effect of fermented cheese whey on Listeria monocytogenes, Escherichia coli O157:H7 and Salmonella Goldcoast populations inoculated onto fresh organic lettuce

Cheese whey fermented by an industrial starter consortium of lactic acid bacteria was evaluated for its antibacterial capacity to control a selection of pathogenic bacteria. For their relevance on outbreak reports related to vegetable consumption, this selection included Listeria monocytogenes, serotype 4b, Escherichia coli O157:H7, and Salmonella Goldcoast. Organically grown lettuce was inoculated with an inoculum level of *107 colonyforming unit (CFU)/mL and was left for about 1 h in a safety cabinet before washing with a perceptual solution of 75:25 (v/v) fermented whey in water, for 1 and 10 min. Cells of pathogens recovered were then counted and their number compared with that obtained for a similar treatment, but using a chlorine solution at 110 ppm. Results show that both treatments, either with chlorine or fermented whey, were able to significantly reduce ( p < 0.05) the number of bacteria, in a range of 1.15–2.00 and 1.59–2.34 CFU/g, respectively, regarding the bacteria tested. Results suggest that the use of fermented whey may be as effective as the solution of chlorine used in industrial processes in reducing the pathogens under study (best efficacy shown for Salmonella), with the advantage of avoiding health risks arising from the formation of carcinogenic toxic chlorine derinfo:eu-repo/semantics/publishedVersio

Validação de metodologia analítica para determinação de oxalato na urina

A validação metodológica permite evidenciar se os resultados obtidos por um método são confiáveis, tornando-se um elemento essencial na qualidade. Neste estudo, cujo objectivo é validar a metodologia enzimática para determinação de oxalato na urina, incluíram-se 30 amostras de urina de 24horas, pré-tratadas e estudadas em dois auto-analisadores. Os valores dos limites de detecção e quantificação foram 0,98 e 0,79 mg/L, respectivamente. Para a exactidão obteve-se p=0,713. Na precisão intermédia entre corridas não existem diferenças estatisticamente significativas, em oposição às repetições. Para a linearidade obteve-se r=1 e a sensibilidade foi 0,6%. Conclui-se que o método se mostrou exacto e linear.Method validation gives evidence if the results obtained by a method are reliable, making it an essential element in quality. In this study, whose aim is to validate the enzymatic method for determination of oxalate in urine, were included 30 urine samples of 24 hours, pre-treated and studied in two auto-analyzers. The values of limit of detection and limit of quantification were 0.98 and 0.79 mg / L, respectively. For the trueness was obtained p=0,713. In the intermediate precision, it appears that between runs there aren´t differences statistically significant, as opposed to repetitions. For the linearity was obtained r=1 and a sensitivity of 0.6%. We concluded that the method was exact and linear

Effect of essential oils on the planktonic of S. aureus and E. coli cells

The essential oils of aromatic plants and their components have a wide range of applications in ethno-medicine, preservation, food flavoring and fragrances and in the perfume industries. Some essential oils derived from plants have revealed promising antimicrobial activity against a wide range of bacteria, including antibiotic resistant species. The aim of this study was to examine the antimicrobial effect of essential oils of Cinnamomum zeylanicum and Cymbopogon martini against planktonic Staphylococcus aureus and Escherichia coli growth. The antimicrobial activity of the essential oils was checked by bacterial growth, at 37 ºC and 120 rpm, in the presence of increasing concentrations of each essential oil for 24 h. Essential oils were dissolved in DMSO (2.0 %) and saline water (0.85 %) with tween 80 (0.5 %) in order to obtain final concentrations of 0.06 %, 0.09 % and 0.12%, for E. coli, and 0.09 %, 0, 12 %, 0.36 % and 0.48 %, for S. aureus. Bacterial planktonic growth over time was followed by the quantification of the number of viable through cultivation of aliquots in TSA. Data showed that E. coli was more sensitive to the action of both essential oils, since complete planktonic growth inhibition was attained with a concentration of 0.09 % of the essential oil of C. zeylanicum oil and 0.06 % of the essential oil of C. Martini. Conversely, S. aureus was less sensitive to the antimicrobial action of the essential oils. C. zeylanicum essential oil inhibited S. aureus growth only at concentrations of 0.36 % and 0.48 %, after 4 and 2 hours of growth. However, unexpectedly after 24 hours those S. aureus cells recovered gradually their planktonic growth. The data pointed out that it is crucial to check the bacterial behavior in the presence of antimicrobial products in different concentrations and over time due to the possible development of bacterial tolerance towards the mechanisms of action of those products. In fact, antimicrobials may have a positive effect in the early hours of application, as demonstrated by some results of this experiment. However, for longer times, the inhibitory effect of antimicrobials can be reverted by bacteria making ineffective their use as disinfectants in food industries. Addiotionally, the continuous exposure of bacteria to antimicrobials can influence the process of microbial resistance de development and increase. These preliminary results demonstrated the possibility of using essential oils of C. zeylanicum and C. martini against two bacteria that are responsible for foodborne illnesses at low concentrations but only for slightly prolonged periods of exposure

Microbial diversity of anaerobic syngas-converting enrichments from a multi-orifice baffled bioreactor (MOBB)

Syngas fermentation can be used to produce fuels and chemicals from lignocellulosic biomass or other poorly biodegradable wastes. The aim of this study was to identify and characterize carboxydotrophic microorganisms in enrichments and evaluate their potential for syngas bioconversion. Anaerobic sludge that efficiently converted syngas (60% CO, 30% H2, 10% CO2) to methane, in a multi-orifice baffled bioreactor (MOBB), was used as inoculum to start enrichments with CO as carbon and energy source. Enrichments were started under a headspace containing 40% CO. Bottles amended with vancomycin and/or erythromycin were also inoculated to test the potential for enriching CO-converting methanogens. Methane and acetate were produced in the enrichment, but no growth or methane production was detected in incubation with antibiotics. In the enrichment, organisms related to Acetobacterium and Sporomusa species were the predominant bacterial species and Methanobacterium and Methanospirillum were the dominant archaea. The enrichment was subcultured and pasteurized to select for spore-forming bacteria and to inactivate methanogens. A stable enrichment culture was obtained that converted up to 100% CO. This enrichment produced hydrogen and acetate. The pasteurized culture showed a low microbial diversity; more than 90% of the community was related to Sporomusa ovata (97% identity). The results suggest that methane production from CO in the MOBB is a combined activity of carboxydotrophic acetogenic bacteria and hydrogenotrophic methanogens. Interestingly, growth of S. ovata with high concentrations of CO was never shown before.info:eu-repo/semantics/publishedVersio

Enrichment of syngas-converting communities from a multi-orifice baffled bioreactor

The substitution of natural gas by renewable biomethane is an interesting option to reduce global carbon footprint. Syngas fermentation has potential in this context, as a diverse range of low-biodegradable materials that can be used. In this study, anaerobic sludge acclimatized to syngas in a multi-orifice baffled bioreactor (MOBB) was used to start enrichments with CO. The main goals were to identify the key players in CO conversion and evaluate potential interspecies metabolic interactions conferring robustness to the process. Anaerobic sludge incubated with 0.7 × 105 Pa CO produced methane and acetate. When the antibiotics vancomycin and/or erythromycin were added, no methane was produced, indicating that direct methanogenesis from CO did not occur. Acetobacterium and Sporomusa were the predominant bacterial species in CO-converting enrichments, together with methanogens from the genera Methanobacterium and Methanospirillum. Subsequently, a highly enriched culture mainly composed of a Sporomusa sp. was obtained that could convert up to 1.7 × 105 Pa CO to hydrogen and acetate. These results attest the role of Sporomusa species in the enrichment as primary CO utilizers and show their importance for methane production as conveyers of hydrogen to methanogens present in the culture.Nederlandse Organisatie voor Wetenschappelijk Onderzoek (024.002.002); FP7 Ideas: European Research Council (323009); Norte 2020 - Sistema de Apoio a Investigação Científica e Tecnol ogica (NORTE-01-0145-FEDER-000004); Fundação para a Ciência e a Tecnologia (PD/BD/128030/2016, SFRH/BPD/104837/ 2014).info:eu-repo/semantics/publishedVersio