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BACKGROUND Worldwide, there is a high attrition rate, or dropout rate, from combat in trained soldiers, mainly due to musculoskeletal injuries. This study aimed to determine whether the use of an upper limb stability test, the Upper Quarter Y-Balance Test (UQYBT), and a modified version of the Ranger Test (MRT) that included a lower limb step-up endurance test, could predict attrition from combat service in female infantry soldiers. MATERIAL AND METHODS In 2015, a group of 167 newly recruited female light infantry soldiers were evaluated using the UQYBT and the MRT. Data regarding attrition from combat service were collected in 2017, 18 months after screening. Multiple logistic regression analysis was used to determine the predictive effect of body mass index (BMI), UQYBT, and MRT scores on attrition from combat service. RESULTS Fifty-three female soldiers (31.7%) dropped out of combat service during the 18 months following recruitment. The MRT score was a significant predictor of attrition, with each additional incremental increase in the MRT score reducing the attrition rate by 6.8% (OR=0.934; 95% CI, 0.895-0.975). A cutoff MRT score of 12 increments predicted attrition with 73.7% sensitivity and 50.9% specificity. The UQYBT scores and BMI were not significant predictors. CONCLUSIONS The use of the MRT during military training, was a predictive screening method to predict attrition from combat service in Israeli female infantry soldiers. Further studies are required to evaluate the use of the MRT in other groups of women in the military.

[Purpose] This study examined whether the interval at the target angle during knee joint position sense (JPS) affected reposition accuracy, and evaluated the consequence of this factor on test-retest reliability. [Subjects and Methods] Twenty healthy subjects participated in this study. Reposition ability was measured after the knee was placed at a target angle (ranging from 40° to 60°) for intervals of 3, 6, 9, and 12 seconds, in randomized order. Two trials were performed for each condition. The measurement was repeated after a week. The absolute error (AE) of each trial and average AE under each condition within the two measures were used for data analysis. [Results] No significant difference was found in comparing the AE or the average AE during all trials and between the two measures. Fair-to-good reliability was found for the AE results of all trials under the conditions of 3, 6, and 12 seconds. Poor reliability was found with time interval of 9 seconds. [Conclusion] The length of time needed to memorize the target angle during knee JPS test might affect test reliability. Practitioners can use this information when collecting JPS data.

Antioxidant activity of symbiotic organisms known as lichens is an intriguing field of research because of its strong contribution to their ability to withstand extremes of physical and biological stress (e.g. desiccation, temperature, UV radiation and microbial infection). We present a comparative study on the antioxidant activities of 76 Icelandic and 41 Hawaiian lichen samples assessed employing the DPPH- and FRAP-based antioxidant assays. Utilizing this unprecedented sample size, we show that while highest individual sample activity is present in the Icelandic dataset, the overall antioxidant activity is higher for lichens found in Hawaii. Furthermore, we report that lichens from the genus Peltigera that have been described as strong antioxidant producers in studies on Chinese, Russian and Turkish lichens also show high antioxidant activities in both Icelandic and Hawaiian lichen samples. Finally, we show that opportunistic sampling of lichens in both Iceland and Hawaii will yield high numbers of lichen species that exclusively include green algae as photobiont., (© 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.)

From the organic extracts of two Guam sponges, Rhaphoxya sp. and Suberea sp., determined to have cytotoxic and chemopreventive activities, three new compounds, theonellin isocyanate (1) and psammaplysins I and J (5, 6), and six previously reported compounds (2-4, 7-9) were isolated and characterized spectroscopically ((1)H and (13)C NMR, MS, IR, UV, [α](D)). The two new metabolites (5 and 6) isolated from the Suberea sp. sponge are rare examples of compounds containing a bromotyramine moiety rather than the more usual dibromo analogue. For the compounds isolated from the Rhaphoxya sp., this is the first report of the known compounds 2-4 being found in a single sponge. For previously reported compounds 2-4 complete unambiguous (1)H and (13)C NMR data are provided.

Marine algae are known to contain a wide variety of bioactive compounds, many of which have commercial applications in pharmaceutical, medical, cosmetic, nutraceutical, food and agricultural industries. Natural antioxidants, found in many algae, are important bioactive compounds that play an important role against various diseases and ageing processes through protection of cells from oxidative damage. In this respect, relatively little is known about the bioactivity of Hawaiian algae that could be a potential natural source of such antioxidants. The total antioxidant activity of organic extracts of 37 algal samples, comprising of 30 species of Hawaiian algae from 27 different genera was determined. The activity was determined by employing the FRAP (Ferric Reducing Antioxidant Power) assays. Of the algae tested, the extract of Turbinaria ornata was found to be the most active. Bioassay-guided fractionation of this extract led to the isolation of a variety of different carotenoids as the active principles. The major bioactive antioxidant compound was identified as the carotenoid fucoxanthin. These results show, for the first time, that numerous Hawaiian algae exhibit significant antioxidant activity, a property that could lead to their application in one of many useful healthcare or related products as well as in chemoprevention of a variety of diseases including cancer.

This paper highlights the importance of recording at least a (1)H nuclear magnetic resonance (NMR) spectrum to verify identity of standards used in analyses of organic materials irrespective of source. We show the importance of this approach with an example of a quantitative high-performance liquid chromatography (HPLC) study undertaken with green tea extracts that required the use of several polyphenols as standards. In the course of the study one of these standards [(-)-epigallocatechin, EGC], although having the physical appearance and appropriate HPLC chromatographic behavior of EGC, proved by (1)H-NMR to be a completely different class of molecule. For us, this raised significant questions concerning validity of many published pieces of research that used quantitative HPLC methods without first performing rigorous validation of the employed standards prior to their use. This paper clearly illustrates the importance of validation of all standards used in analysis of organic materials by recording at least a (1)H-NMR spectrum of them prior to their use.

Photosynthetic oxygen-evolving microorganisms contend with continuous self-production of molecular oxygen and reactive oxygen species. The deleterious effects of reactive oxygen species are exacerbated for cyanobacterial nitrogen-fixers (diazotrophs) due to the innate sensitivity of nitrogenase to oxygen. This renders incompatible the processes of oxygen-evolving photosynthesis and N-fixation. We examined total antioxidative potential of various diazotrophic and non-diazotrophic cyanobacteria. We focused on Trichodesmium spp., a bloom-forming marine diazotroph that contributes significantly to global nitrogen fixation. Among the species tested, Trichodesmium possessed the highest antioxidant activity. Moreover, while proteins constituted the dominant antioxidative component of all other cyanobacteria tested, Trichodesmium was unique in that small-molecule natural products provided the majority of antioxidant activity, while proteins constituted only 13% of total antioxidant activity. Bioassay-guided fractionation followed by high-performance liquid chromatography profiling of antioxidant purified fractions identified the highly potent antioxidant all-trans-β-carotene, and small amounts of 9-cis-β-carotene and retinyl palmitate. Search of the Trichodesmium genome identified protein sequences homologous to key enzymes in the β-carotene to retinyl palmitate biosynthetic pathway, including 33-37% identity to lecithin retinol acyltransferase. The present study demonstrates the importance of carotenoids in Trichodesmium's arsenal of defensive compounds against oxidative damage and protection of nitrogenase from oxygen and its radicals.

Coral reefs are the most biodiverse and biologically productive of all marine ecosystems. Corals harbor diverse and abundant prokaryotic communities. However, little is known about the diversity of coral-associated bacterial communities. Mucus is a characteristic product of all corals, forming a coating over their polyps. The coral mucus is a rich substrate for microorganisms. Mucus was collected with a procedure using sterile cotton swabs that minimized contamination of the coral mucus by surrounding seawater. We used molecular techniques to characterize and compare the bacterial assemblages associated with the mucus of the solitary coral Fungia scutaria and the massive coral Platygyra lamellina from the Gulf of Eilat, northern Red Sea. The bacterial communities of the corals F. scutaria and P. lamellina were found to be diverse, with representatives within the Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Deltaproteobacteria and Epsilonproteobacteria, as well as the Actinobacteria, Cytophaga-Flavobacter/Flexibacter-Bacteroides group, Firmicutes, Planctomyces, and several unclassified bacteria. However, the total bacterial assemblage of these two corals was different. In contrast to the bacterial communities of corals analyzed in previous studies by culture-based and culture-independent approaches, we found that the bacterial clone libraries of the coral species included a substantial proportion of Actinobacteria. The current study further supports the finding that bacterial communities of coral mucus are diverse.

Coral reefs are the most biodiverse of all marine ecosystems. Bacteria are known to be abundant and active in seawater around corals, inside coral tissues, and within their surface microlayer. Very little is known, however, about the structure, composition and maintenance of these bacterial communities. In the current study we characterize the culturable bacterial community within the mucus of healthy specimens of the Red Sea solitary coral Fungia scutaria. This was achieved using culture-based methods and molecular techniques for the identification of the bacterial isolates. More than 30% of the isolated bacteria were novel species and a new genus. The culturable heterotrophic bacterial community of the mucus of this coral is composed mainly of the bacterial groups Gammaproteobacteria, Alphaproteobacteria and of Actinobacteria. This study provides the first evidence of actinomycetes isolated from corals.

Evidence is presented that the radical observed upon reaction of myoglobin with hydrogen peroxide is a peroxyl radical. Simulation of this spectrum gives principal values for the g tensor of gx = 2.0357, gy = 2.0082, and gz = 2.0016, which are consistent with those of a peroxyl radical. Use of molecular oxygen isotopically labeled with 17O confirmed that the radical observed was a peroxyl radical. Removal of oxygen from the incubation by use of glucose and glucose oxidase revealed two radicals, one at giso = 2.0028 and the other at giso = 2.0073. Addition of various amounts of the spin trap 5,5-dimethyl-1-pyrroline N-oxide revealed that the spin trap and oxygen compete for the same radical site. Four model substrates, glutathione, styrene, arachidonic acid and linoleic acid, were individually added to both the aerobic and anoxic systems. Glutathione reacted with the peroxyl radical, reducing its intensity by 98%, and entirely eliminated the giso = 2.0028 line from the spectrum of the anoxic incubation. Styrene, arachidonic acid and linoleic acid reacted with the peroxyl radical, reducing its amplitude by 84, 57, and 35%, respectively, but did not decrease the amplitude of either radical species in the anoxic incubation. The giso = 2.0028 species detected in the anoxic incubation appears to be the original radical site to which molecular oxygen binds to form the peroxyl radical. This myoglobin-derived peroxyl radical species is responsible for the advent of lipid peroxidation as proposed in ischemia/reperfusion injury, as well as other reactions, as exemplified by the O2-dependent epoxidation of styrene.

The characterization of the radical formed from rat hemoglobin (Hb) by methemoglobin-generating agents and trapped by 5,5-dimethyl-1-pyrroline N-oxide (DMPO) has shown it to be a thiyl radical. The two-electron oxidation of hemoglobin forms a ferryl species with one or more free radicals located on the globin moiety. While the radical species has not been observed by use of uv-visible spectrophotometry, the species can be detected by use of electron paramagnetic resonance spectroscopy (EPR). In previous studies, in vitro experiments have shown that the EPR signal from the rat Hb radical adduct formed by t-butyl hydroperoxide decreased following pretreatment of the oxyHb with thiol-blocking agents except for iodoacetamide. In this study the power saturation profile of the DMPO radical adduct obtained from the reaction of rat oxyHb with phenylhydrazine exhibited a pattern similar to that obtained from human oxyHb, in which the beta-93 cysteine was labeled with 2,2,6,6-tetramethyl-1-piperidinyloxy-4-maleimide (4-maleimide-TEMPO). EPR spectra were taken at 77 K and computer simulations were performed. The calculated value for a(iso)N obtained by simulation indicates that the radical adduct is in a hydrophobic region. The value for a(iso)H has little structural significance, as the steric effect of the protein makes comparison with radical adducts in solution problematical. The value of gx from the rat Hb radical adduct was significantly higher than that obtained from bovine Hb, whose radical is not thiol-derived, as demonstrated by negative thiol-blocking agent experiments. A higher gx value is consistent with the radical adduct containing a heavy atom such as sulfur. Rat Hb was analyzed for thiol content by use of iodoacetamide, 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB) and uv-visible spectrophotometry. It was found that 1.15 +/- 0.34 thiols/tetramer of Hb were reactive with DTNB, but not iodoacetamide.

It was reported that the electron paramagnetic resonance (EPR) spectrum of 5,5-dimethyl-1-pyrroline N-oxide (DMPO)/lipid alkoxyl radical exhibited a quartet with 1:2:2:1 relative intensity that is identical to that of DMPO/hydroxyl radical (K. M. Schaich and D. C. Borg, 1990, Free Radicals Res. Commun. 9, 267-278). We repeated these EPR experiments using HPLC separation of radical adducts and isotope substitution. We found that the HPLC/EPR chromatogram of the radical adduct with a 1:2:2:1 quartet obtained by the reduction of methyl linoleate hydroperoxide (MLOOH) with Fe2+ exhibited identical retention time to that of the DMPO/OH radical adduct obtained from the Fenton reaction in two different solvent systems. Upon performing the same reaction in 17O-enriched water, the 17O-hyperfine coupling constants due to DMPO/17OH were identified. Ultimately, approximately 80-90% of the total DMPO/OH is derived from water by an iron-dependent nucleophilic addition reaction. Initially, a water-independent mechanism also significantly contributes to DMPO/OH formation. Regardless of its mechanism of formation, the 1:2:2:1 quartet radical adduct of DMPO formed during the reduction of MLOOH by Fe2+ is in fact DMPO/OH.

The reductive cleavage of hydrogen peroxide by metmyoglobin produces a protein-derived, motionally restricted free radical detectable by the spin-trapping EPR technique. In order to determine if the detected radical was a peroxyl radical, 17O2 and anoxic conditions were employed. The EPR spectra of the metmyoglobin-derived radical adduct detected under nitrogen incubations were identical to those of the oxygenated systems in both intensity and form. No additional hyperfine couplings were detected in the EPR spectrum when 17O2 was used. Both of these results indicate that a peroxyl radical derived from molecular oxygen was not found. Additionally, spectra of spin trapped metmyoglobin from four different mammalian species were examined. No significant difference was seen among any of the species, even though one of the species, sperm whale, has one more tyrosine residue than the others.

DNA damage was induced by irradiating calf-thymus DNA with a GE Maxitron-250 as an X-ray source. The use of nitrous oxide as a scavenger of solvated electrons in the irradiation process, resulted in essentially a monoreactant system of the biologically important hydroxyl radical. A novel approach combining the enzymatic digestion of the irradiated DNA to nucleoside 5' monophosphates and fluorescence postlabeling was applied to detect a specific modified nucleotide induced by ionizing radiation, namely the 5,6-dihydroxy-5,6-dihydrothymine lesion. This modification, often referred to as the glycol lesion, is polar and is generated mainly as the cis stereoisomers. In order to demonstrate the detection of this lesion in DNA by fluorescence labeling, the lesion was first produced chemically in a DNA model compound d(CGTA). The modified oligomers were isolated intact by HPLC and characterized by NMR as cis stereoisomers of glycol derivatives of d(CGTA). The major isomer of the modified d(CGTA) was enzymatically digested to yield 5' monophosphates. The digest was chromatographed by HPLC to enrich the modified nucleotide. The fraction containing the modified nucleotide was labeled with dansyl chloride. The fluorescent labeled nucleotide was chromatographed by HPLC. The same overall procedure was applied to DNA X-irradiated in aqueous solution. With a conventional fluorescence detector, HPLC analysis of the fluorescence labeled nucleotides detected 1 modified nucleotide/10(6) normal nucleotides from 100 micrograms DNA. The two cis glycol lesions were detected in the irradiated DNA by co-chromatography with fluorescent labeled markers. The initial assay of the modified oligomer demonstrated that the same stereoisomer of cis glycol was induced as a major modified nucleotide by both chemical oxidation and ionizing radiation.

A facile method was developed to covalently attach a fluorophore to the 5'-phosphate of a nucleic acid. The procedure, illustrated by coupling 5'-dNmp (N = A,C,G,T) with 5-dimethylaminonaphthalene 1-sulfonyl chloride, commonly known as Dansyl chloride, involves 5'-phosphoramidation with ethylenediamine (EDA) followed by conjugation of the free aliphatic amino group of the phosphoramidate with Dansyl chloride. This method is also applicable to multi-incorporation of fluorescent labels in the nucleic acids. The reaction of 5'-Amp with a polyamine such as poly L-lysine (PLL, mol. wt., 4000) resulted in a phosphoramidate with multiple amino groups, which after isolation and conjugation with fluorescamine gave dAmp with multilabeled fluorophores. A condition was devised to separate the four dansylated mononucleotides of DNA, conjugated via ethylenediamine linker, by reverse phase HPLC. The elution profile could be monitored with a variable wavelength detector at 254 nm and 340 nm corresponding to the absorption of the nucleotides and the dansyl moiety, respectively. The detection limit was 2 nmol at 254 nm. The use of a fluorescence detector enhanced the detection sensitivity to a sub-picomole level (200 fmol). Samples of a DNA model, d(pCpGpTpA) and calf-thymus DNA were digested enzymatically to 5'-mononucleotides and labeled with Dansyl chloride. HPLC analysis of the dansylated digests from these samples, both before and after irradiation, suggests that the combination of enzymatic digestion and fluorescence postlabeling could be a novel approach to assay DNA damage.