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ABSTRACT Raman spectra of human hair cuticle measured in two experimental configurations with linearly polarized radiation focused on the lateral surface of the hair and on its cross section are compared. The bands at ~150, 220–230, 900, 935, 1321, 1338, and 1652 cm−1 are found to be polarization‐sensitive and assigned to the skeletal vibrations of α‐helices of hair keratins. However, different Raman spectra depending on the relative direction of signal collection can be obtained under identical polarization conditions for excitation. Several markers of the secondary structure of keratins (in particular, ~150, 935, and 1338 cm−1) may also be sensitive to the changes in the tertiary structure. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa is a ubiquitous Gram-negative bacterium able to survive in diverse environments such as soil, plants, freshwater, and seawater. P. aeruginosa can be an opportunistic pathogen to humans when their immune system is deficient. Its pathogenicity may be linked to the production of virulence factors. We isolated P. aeruginosa strain RBS from the saltern of Sfax in Tunisia. In this study, we characterized the halotolerance, antibiotic susceptibility, and some virulence factors of strain RBS. High NaCl concentrations inhibited growth and motility. However, biofilm formation was enhanced to protect bacteria against salt stress. Among the 18 antibiotics tested, quinolones and tetracycline showed a significant inhibitory effect on growth, motility, and biofilm formation of strain RBS. β-Lactams, however, did not have any inhibitory effect on neither bacterial growth nor motility. In some cases, resistance was due, in part, to biofilm formation. We also showed that RBS produces two proteases, LasB and AprA, which have been shown to be implicated in host infection. LasB was further characterized to study the role of metal ions in enzyme stability. It possesses two distinct metal ion-binding sites coordinating a calcium and a zinc ion. The effect of metal ion chelation was evaluated as well as substitutions of residues involved in metal ion binding. Impairing metal ion binding of LasB led to a loss of activity and a sharp decrease of stability. Our findings suggest that the binding of both metal ions is interdependent as the two metal ions' binding sites are linked via a hydrogen bond network. [ABSTRACT FROM AUTHOR]

Abstract: Confocal Raman microspectroscopy is used to substantially supplement existing experimental data on historical blue‐green beads with respect to the presence and distribution of potassium antimony silicate (KSS) crystals. Problem of degradation of blue‐green beads on historical artifacts accounts for topicality of the work. The reasons for possible short‐term (several years) degradation of beads and the presence of neighboring damaged and undamaged beads on a single item remain unknown in spite of multiple experimental works on various glasses. Presence of KSS microcrystals may serve as a reason for degradation of beads. Raman measurements at several depths are used to determine the distribution and estimate sizes of KSS microcrystals. Such distributions are different for undamaged and strongly degraded beads. For degraded beads, Raman data show the depth dependence of the concentration of (non)bridged oxygens in the near‐surface layer with a thickness of 3–4 μm (i.e., inhomogeneity of glass matrix). The results prove the growth of KSS microcrystals in historical blue‐green beads, which may cause internal stress and, hence, degradation. The results can be used for optimization of storage conditions and restoration procedures for historical items. [ABSTRACT FROM AUTHOR]

During the oestrus cycle, varying spine synapse density correlates positively with varying local synthesis of oestradiol in the hippocampus. In this context, the roles of the oestrogen receptor ( ER) subtypes ERα and β are not fully understood. In the present study, we used neonatal hippocampal slice cultures from female rats because these cultures synthesise oestradiol and express both receptor subtypes, and inhibition of oestradiol synthesis in these cultures results in spine synapse loss. Using electron microscopy, we tested the effects on spine synapse density in response to agonists of both ERα and ERβ. Application of agonists to the cultures had no effect. After inhibition of oestradiol synthesis, however, agonists of ERα induced spine synapse formation, whereas ERβ agonists led to a reduction in spine synapse density in the CA1 region of these cultures. Consistently, up-regulation of ERβ in the hippocampus of adult female aromatase-deficient mice is paralleled by hippocampus-specific spine synapse loss in this mutant. Finally, we found an increase in spine synapses in the adult female ERβ knockout mouse, but no effect in the adult female ERα knockout mouse. Our data suggest antagonistic roles of ERβ and ERα in spine synapse formation in the female hippocampus, which may contribute to oestrus cyclicity of spine synapse density in the hippocampus. [ABSTRACT FROM AUTHOR]

Aim: Glucose ingestion may improve exercise endurance, but it apparently also influences the transcription rate of several metabolic genes and it alters muscle metabolism during an acute exercise bout. Therefore, we investigated how chronic training responses are affected by glucose ingestion. Methods: In previously untrained males performance and various muscular adaptations were evaluated before and after 8 weeks of supervised endurance training conducted either with ( n = 8; CHO group) or without ( n = 7; placebo) glucose supplementation. Results: The two groups achieved similar improvements in maximal oxygen uptake and peak power output during incremental cycling (both parameters elevated by 17% on average) and both groups lost ∼3 kg of fat mass during the 8 weeks of training. An equal reduction in respiratory exchange ratio (0.02 units) during submaximal exercise was observed in both groups. Beta-hydroxyacyl-CoA-dehydrogenase activity was increased in both groups, however, to a larger extent in the placebo group (45 ± 11%) than CHO (23 ± 9%, P < 0.05). GLUT-4 protein expression increased by 74 ± 14% in the placebo group and 45 ± 14% in CHO (both P < 0.05), while resting muscle glycogen increased ( P < 0.05) to a larger extent in the placebo group (96 ± 4%) than CHO (33 ± 2%). Conclusion: These results show that carbohydrate supplementation consumed during exercise training influences various muscular training adaptations, but improvements in cardiorespiratory fitness and reductions in fat mass are not affected. [ABSTRACT FROM AUTHOR]

Sex-dependent differences in learning and memory formation in humans have been frequently shown. The mechanisms underlying the formation and retention of memories are assumed to involve synaptic plasticity in the hippocampus. Estradiol was shown to effect synaptic plasticity in the hippocampus of rodents. The effects after exogenous application of estradiol to animals frequently produce inconsistent results, in particular, if sex is not considered in the studies. Recently we provided evidence that locally synthesized estradiol plays an essential role on synaptic connectivity in the hippocampus of females but not of male mice. In females, inhibition of local estradiol synthesis leads to synapse loss, which results from impairment of long-term potentiation and dephosphorylation of cofilin, and thereby the destabilization of postsynaptic dendritic spines. This sex-dependency was also seen in the classical aromatase knock-out mouse. Intriguingly, no differences between sexes have been found in a conditional forebrain-specific aromatase knock-out mouse. Altogether, the findings underscore the necessity of including 'Sex as a Biological Variable' in studies of sex steroid-induced synaptic plasticity., (© 2019 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)

Aim: To investigate whether the mineralocorticoid receptor antagonist eplerenone has beneficial effects on liver fat and metabolism in patients with type 2 diabetes (T2D), the mineralocorticoid receptor antagonist in type 2 diabetes (MIRAD) trial., Material and Methods: In this 26-week, double-blind, randomized, placebo-controlled trial, we enrolled 140 patients with T2D and high risk of cardiovascular disease. Patients were randomized 1:1 to either eplerenone with a target dose of 200 mg/day for patients with estimated glomerular filtration rate (eGFR) of 60 mL/min per 1.73 m 2 or more and 100 mg/day for patients with eGFR between 41 and 59 mL/min per 1.73 m 2 or placebo. The primary outcome measure was change in liver fat by proton magnetic resonance spectroscopy at week 26 from baseline; secondary outcomes were changes in metabolism, and safety by incident hyperkalaemia., Results: No changes in liver fat in the eplerenone group 0.91% (95% CI -0.57 to 2.39) or the placebo group -1.01% (-2.23 to 0.21) were found. The estimated absolute treatment difference was 1.92% (-3.81 to 0.01; P = 0.049). There was no beneficial impact on supporting secondary outcome variables of metabolism as fat mass distribution, lipid metabolism or insulin resistance. Despite a high dosage of eplerenone 164 versus 175 mg in patients treated with placebo (P = 0.228), the number of patients with incident hyperkalaemia (≥5.5 mmol/L) was low, with six in the eplerenone versus two in the placebo group (P = 0.276)., Conclusion: The addition of high doses of eplerenone to background antidiabetic and antihypertensive therapy does not show beneficial effects on liver fat and metabolism in patients with T2D., (© 2019 John Wiley & Sons Ltd.)

Cystic fibrosis is the most common, severe, inherited disease in the Caucasian population. As a consequence, the demand for genetic counselling of patients with cystic fibrosis and their families is large. In Denmark the incidence of cystic fibrosis is 1:4700, which is quite low compared to other European countries. We have investigated 268 Danish cystic fibrosis patients with respect to DNA markers (haplotypes) and the most common mutation delta F508. The delta F508 mutation is found on 88% of all cystic fibrosis chromosomes, the highest frequency reported so far. This had had an important impact on genetic counselling, prenatal diagnosis and eventually population screening. In the Danish population 78% of all couples at risk will be informative for delta F508 and will be identifiable by simple screening methods.