Is There a Role of Beetroot Consumption on the Recovery of Oxidative Status and Muscle Damage in Ultra-Endurance Runners?

(1) Background: Ultra-endurance exercise involves a high physical impact, resulting in muscle damage, inflammatory response and production of free radicals that alter the body's oxidative state. Supplementation with antioxidants, such as beetroot, may improve recovery in ultra-endurance runners. The aim of this study was to determine whether there is a correlation between beetroot intake and recovery of serum oxidative status, inflammatory response and muscle damage parameters after an ultra-endurance race. (2) Methods: An observational and longitudinal study was conducted by means of surveys and blood samples collected from 32 runners during the IX Penyagolosa Trails CSP®® race and the two following days. The variables C-reactive protein (CRP), lactate dehydrogenase (LDH), creatine kinase (CK), the activity of the antioxidant enzymes glutathione peroxidase (GPx) and glutathione reductase (GR) as well as the oxidative damage markers malondialdehyde (MDA), carbonyl groups (CG) and loss of muscle strength using the squat jump (SJ) test were analyzed to discriminate whether beetroot consumption can modulate the recovery of ultra-trail runners. (3) Results: Significant differences were observed between runners who ingested beetroot and those who did not, in terms of oxidative status, specifically in serum GPx activity at 24 and 48 h, muscle damage variables CK and LDH and regarding the SJ test results at the finish line. Therefore, the intake of supplements containing beetroot positively influences the recovery of serum oxidative status and muscle damage after ultra-endurance running.

Clinical assessment of the lower tear meniscus height.

PURPOSE: Different values of the lower tear meniscus height (TMH) can be obtained depending on the method and technique of measurement employed. This study aimed to assess (1) differences between the absolute (TMH-A), reflex (TMH-R) and fluorescein (TMH-F) lower tear meniscus heights, (2) differences between the central (TMH-R), nasal (TMH-RN) and temporal (TMH-RT) reflex lower tear meniscus heights and (3) the amount of fluorescein present in the lower tear meniscus, 5 min after fluorescein instillation (TMH-FV). METHODS: Thirty four young healthy subjects were included in the study. The lower tear meniscus height (TMH) was measured using an eye piece graticule inserted into a slit-lamp. RESULTS: Mean +/- S.D. values of TMH-A, TMH-R, TMH-RN, TMH-RT, TMH-F and TMH-FV of 0.25 +/- 0.08, 0.13 +/- 0.05, 0.23 +/- 0.06, 0.21 +/- 0.05, 0.27 +/- 0.11 and 0.004 +/- 0.001 mm, respectively were found. The TMH-R was significantly lower than the TMH-A and the TMH-F (p < 0.0001). The TMH-RN and TMH-RT were significantly higher than the TMH-R (p < 0.0001). The TMH-F was significant higher than the TMH-FV (p < 0.0001). No significant differences were found between the TMH-A and TMH-F (p = 0.2), and between the TMH-RN and TMH-RT (p = 0.36). CONCLUSION: Careful instillation of fluorescein does not affect normal TMH values. Fluorescein is washed out from the lower tear meniscus 5 min after instillation. Higher values of the TMH can be found at nasal and temporal locations compared to the center of the lower eye lid.

Bacterial adhesion to worn silicone hydrogel contact lenses.

PURPOSE: The aim of this study was to, firstly, investigate whether silicone-hydrogel contact lenses (CL) are more or less susceptible to bacterial adhesion than conventional ones and, secondly, assess the influence of lens wear in the extent of bacterial adhesion. Four silicone-hydrogel CL (galyfilcon A, balafilcon A, lotrafilcon A, and lotrafilcon B) and one conventional hydrogel (etafilcon A) CL were tested. METHODS: Bacterial adhesion experiments were performed on unworn and worn CL using the strain Staphylococcus epidermidis 9142. Worn lenses were obtained from a group of 31 subjects fitted with a silicone-hydrogel CL in one eye and a conventional hydrogel CL as contralateral pair. These lenses were used on a daily basis in combination with a multipurpose lens care solution. Adhesion assays were carried out in a parallel plate flow chamber, followed by image analysis. Hydrophobicity, roughness, and topography of the lenses surfaces were assessed through contact angle measurements and atomic force microscopy. RESULTS: Unworn conventional and silicone-hydrogel CL were equally susceptible to bacterial adhesion of S. epidermidis. Conversely, worn conventional hydrogel (etafilcon A) were more prone to bacterial adhesion than worn silicone-hydrogel materials, which exhibited similar adhesion extents among them. The results also showed that the lens surface properties such as hydrophobicity, roughness, and surface topography changed during wear. The alteration of surface hydrophobicity of silicone and conventional hydrogel CL during wear had a great impact on lens bacterial adhesion susceptibility. Accordingly, balafilcon A becomes significantly less hydrophobic and less prone to bacterial adhesion after lens wear, whereas etafilcon A becomes more hydrophobic and also more susceptible to bacterial adhesion (p < 0.05). CONCLUSIONS: Worn silicone-hydrogel galyfilcon A, balafilcon A, lotrafilcon A, and lotrafilcon B are equally prone to microbial adhesion of S. epidermidis and generally less susceptible than the conventional hydrogel.

The influence of lens material and lens wear on the removal and viability of Staphylococcus epidermidis.

PURPOSE: The aim of this study was to evaluate the influence of lens material and lens wear on the removal capability of Staphylococcus epidermidis. Assessment of viability of remaining adhered bacteria was another goal of this work. Four silicone hydrogel materials (galyfilcon A, balafilcon A, lotrafilcon A, lotrafilcon B) and one conventional hydrogel material (etafilcon A) were assayed. METHODS: Detachment studies on S. epidermidis were carried out in a parallel plate flow chamber. Contact lenses (CLs) were fitted to the bottom of the flow chamber and a bacterial suspension was perfused into the system, promoting bacterial adhesion. Afterwards, detachment was stimulated using a multipurpose solution (MPS, ReNu Multiplus) and the percentage of removed bacteria estimated through microscopic observation and enumeration. Remaining adhered bacteria were stained with propidium iodide (PI) and enumerated in order to assess their viability. Additionally, the worn lenses were observed by confocal laser scanning microscopy (CLSM) to visualize bacterial distribution along the lens surfaces. RESULTS: Bacterial removal was significant (p<0.05) for both unworn and worn galyfilcon A and etafilcon A. Galyfilcon A exhibited a detachment percentage of 59.1 and 63.5 while etafilcon A of 62.6 and 69.3, both for unworn and worn lenses, respectively. As far as bacterial viability is concerned, it was found that worn lenses exhibit a superior amount of non-viable bacteria than unworn CLs. Images obtained by CLSM revealed an irregular bacterial distribution for all lens materials. CONCLUSIONS: It appears that surface and/or bulk structure of the lens material affects removal of S. epidermidis while CL wear influences their viability.

The effect of octylglucoside and sodium cholate in Staphylococcus epidermidis and Pseudomonas aeruginosa adhesion to soft contact lenses.

PURPOSE: In this study, the effect of the natural surfactants octylglucoside and sodium cholate in inhibiting Staphylococcus epidermidis and Pseudomonas aeruginosa adhesion to conventional and silicone-hydrogel contact lenses (CL) was assessed. Hydrophobicity was also evaluated to conditioned and nonconditioned CL. METHODS: The inhibiting effect of the tested surfactants was determined through "in vitro" adhesion studies to conditioned and nonconditioned CL followed by image acquisition and cell enumeration. Hydrophobicity was evaluated through contact angle measurements using the advancing type technique on air. RESULTS: Sodium cholate exhibits a very low capability to inhibit microbial adhesion. Conversely, octylglucoside effectively inhibited microbial adhesion in both types of lenses. This surfactant exhibited an even greater performance than a multipurpose lens care solution used as control. Octylglucoside was the only tested surfactant able to lower the hydrophobicity of all CL, which can explain its high performance. CONCLUSIONS: The results obtained in this study point out the potential of octylglucoside as a conditioning agent to prevent microbial colonization.

The influence of surface treatment on hydrophobicity, protein adsorption and microbial colonisation of silicone hydrogel contact lenses.

PURPOSE: To evaluate the influence of surface treatment of silicone-hydrogel CL on lens hydrophobicity, protein adsorption and microbial colonisation by studying several silicone hydrogel contact lenses (CL) with and without surface treatment. The lenses used in this study were Balafilcon A, Lotrafilcon A, Lotrafilcon B and Galyfilcon A. A conventional hydrogel CL (Etafilcon A) was also tested. METHODS: Hydrophobicity was determined through contact angle measurement using the advancing type technique on air. The type and quantity of proteins adsorbed were assessed through SDS-PAGE and fluorescence spectroscopy, respectively. Microbial colonisation was studied by removing the microbes from the lenses through sonication, and counting the colony-forming units on agar plates. RESULTS: Regarding hydrophobicity, both surface and non-surface-treated silicone hydrogel CL were found to be hydrophobic, and the conventional hydrogel CL was found to be hydrophilic. Concerning protein adsorption, different protein profiles were observed on the several lenses tested. Nevertheless, the presence of proteins with the same molecular weight as lysozyme and lactoferrin was common to all lenses, which is probably related to their abundance in tears. In terms of total protein adsorption, silicone hydrogel CL did not exhibit any differences between themselves. However, the conventional hydrogel Etafilcon A adsorbed a larger amount of proteins. Regarding microbial colonisation, Balafilcon A exhibited the greatest amount of colonising microbes, which can be due to its superior hydrophobicity and higher electron acceptor capacity. CONCLUSION: This study suggests that silicone hydrogel lenses adsorb a lower amount of proteins than the conventional hydrogel lenses and that this phenomenon is independent of the presence of surface treatment. Concerning microbial colonisation, the surface treated Balafilcon A, exhibited a greater propensity, a fact that may compromise the lens wearer's ocular health.