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Lantibiotics are promising candidates to address the worldwide problem of antibiotic resistance. They belong to a class of natural compounds exhibiting strong activity against clinically relevant Gram-positive bacterial strains, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE). Lichenicidin is a class II two-peptide lantibiotic. The presence of the two mature peptides, Bliα and Bliβ, is necessary for full activity against target bacteria. This work aims at clarifying the synergistic activity of both peptides in their interaction with the target membranes. The effect of lichenicidin was tested against S. aureus cells and large unilamellar vesicles. Lichenicidin increases the net surface charge of S. aureus, as shown by zeta-potential measurements, without reaching electroneutralization. In addition, lichenicidin causes cell surface perturbations that culminate in the leakage of its internal contents, as observed by atomic force microscopy. Bliα seems to have low affinity for S. aureus, however, it contributes to increase the affinity of Bliβ, because together they present higher affinity than separately. In contrast, Bliα seems to provide an anchoring site for lichenicidin in lipid II-containing membranes. Interestingly, Bliβ alone can induce high levels of membrane leakage, but this effect appears to be faster in the presence of Bliα. Based on this information, we propose a mechanism of action of lichenicidin., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Small-scale fishers in the developing world have been particularly affected by the COVID-19 pandemic given that they belong to one of the most socioeconomically vulnerable groups. In Brazil, one of the countries most affected by the pandemic, it was expected early on that the economy and wellbeing of fishers would be negatively impacted, yet fishers were expected to show some adaptive and coping mechanisms. To assess whether this was the case, 40 fishers, who are also leaders of fishing associations representing over 80 thousand fishers throughout the country, were interviewed. Results revealed that female leaders appraised the economic and health / wellbeing impacts to be harsher on fishers than men did. Moreover, fishers on the coast were found to be better able to adapt than those inland, although both had low levels of adaptive capacity. The nature of coping and adaptive mechanisms was also found to be different between locations. Whereas leaders from coastal associations stated that most of the adaptive responses occurred in the post-harvest sector (e.g., changes to the types of sales and changes to supply chain actors), leaders from inland communities stated that the changes that occurred related specifically to fishing (e.g., decrease in effort and changes in fishing grounds). These findings suggest that: 1) women may be better prepared to respond to COVID-19 because their appraisal may be more realistic than men, 2) the historic vulnerability of fishing communities may limit their adaptative capacity, and 3) coastal fishers have likely found ways to maintain part of their trade, contrary to inland fishers. Thus, to better help small-scale fisheries to cope with this particular pandemic or other large disruptive impacts, it would be recommended to invest in women in leadership roles while also guaranteeing that fishers have the minimal conditions to cope with and adapt to impacts. The latter can be done by assuring emergency cash transfers for the duration of the impact, as with the still ongoing pandemic, and investing in building fisher resilience for future shocks., (© 2021 Elsevier Ltd. All rights reserved.)

The seasonal assessment of anthropogenic activities in the Vaza Barris estuarine river system, located in the Sergipe state, northeastern Brazil, was performed using the aliphatic hydrocarbon distribution. The aliphatic hydrocarbon and isoprenoid (Pristane and Phytane) concentrations ranged between 0.19 μg g(-1) and 8.5 μg g(-1) of dry weight. Data were analyzed using Kruskal-Wallis test, with significance level set at p<0.05, and no seasonality distribution change was observed. The Carbon Preference Index (CPI), associated with n-alkanes/n-C16, Low Molecular Weight/High Molecular Weight ratio (LMW/HMW) and Terrigenous to Aquatic Ratio (TAR) suggested biogenic input of aliphatic hydrocarbons for most samples, with significant contribution of higher plants., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Herein, we used an electrospinning process to develop highly efficacious and hydrophobic coaxial nanofibers based on poly-cyclodextrin (polyCD) associated with poly(methacrylic acid) (PMAA) that combines polymeric and supramolecular features for modulating the release of the hydrophilic drug, propranolol hydrochloride (PROP). For this purpose, polyCD was synthesized and characterized, and its biocompatibility was assessed using fibroblast cytotoxicity tests. Moreover, the interactions between the guest PROP molecule and both polyCD and βCD were found to be spontaneous. Subsequently, PROP was encapsulated in uniaxial and coaxial polyCD/PMAA nanofibers. A lower PROP burst effect (reduction of approximately 50%) and higher modulation were observed from the coaxial than from the uniaxial fibers. Thus, the coaxial nanofibers could potentially be a useful strategy for developing a controlled release system for hydrophilic molecules., (Copyright © 2015 Elsevier B.V. All rights reserved.)

We investigated the acute effects of musical auditory stimulation on cardiac autonomic responses to a mental task in 28 healthy men (18-22 years old). In the control protocol (no music), the volunteers remained at seated rest for 10 min and the test was applied for five minutes. After the end of test the subjects remained seated for five more minutes. In the music protocol, the volunteers remained at seated rest for 10 min, then were exposed to music for 10 min; the test was then applied over five minutes, and the subjects remained seated for five more minutes after the test. In the control and music protocols the time domain and frequency domain indices of heart rate variability remained unchanged before, during and after the test. We found that musical auditory stimulation with baroque music did not influence cardiac autonomic responses to the mental task., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The objective of this experiment was to test the effects of the addition of chlorine to broiler drinking water during a 12-h preslaughter feed withdrawal period on reduction of the quantities of microorganisms, such as Escherichia coli and enterococci, in broiler crops and ceca. Reduction of these microorganisms would likely also reduce contamination of broiler meat by pathogenic bacteria during processing. It was also investigated if the chlorine caused some intestinal damage that could disseminate the microorganisms to the carcass. A total of 40 Cobb male broilers were used. Samples of crop and cecal content were collected for microbiological analysis, and duodenum and jejunum were used for morphological analysis from 10 birds in each treatment. The most probable number (MPN) of E. coli and enterococci in the collected samples of crop and ceca and the measure of the free residual chlorine in water were determined. The scanning electron microscopy from duodenum and jejunum was used to illustrate the mucosa integrity. The chlorine added to water was efficient in reducing the quantities of microorganisms in broiler crops and improved the integrity of the mucosa. Therefore, preslaughter feed withdrawal should be coupled with crop disinfection, because preslaughter feed withdrawal increases the MPN of enterococci and E. coli in broiler crops. So, it presents a higher risk for carcass contamination during slaughterhouse processing and, consequently, a higher risk for public health.

This work aimed to assess the effect of the fungus Metarhizium anisopliae on off-host Rhipicephalus (Boophilus) microplus from tick-infested Brachiaria decumbens pasture undergoing cattle grazing. For this purpose a naturally tick-infested Brachiaria decumbens pasture of 60 m × 100 m with twelve grazing Holstein Friesian-Nelore (Bos indicus) cross breed bovines was sprayed 12 times, 21 days apart with an aqueous conidial suspension of the E9 isolate of M. anisopliae fungus. Control pasture was treated with conidial suspension vehicle only. Efficacy of treatment was evaluated by tick larvae counts on the pasture and that of engorged female ticks on grazing cattle. Fungus persistence on grass stems as well as soil pasture was assessed after each spray. Efficacy of fungus against ticks was also measured by an in vitro immersion test. Whereas in vitro test showed a clear pathogenic effect of the fungus on ticks, no pathogenic effect over R. (B.) microplus ticks was detected in the field trial by spraying pasture with fungal suspension. Fungus from the suspension could be recovered from both the grass stem as well as the soil of sprayed pasture, even though the numbers obtained varied distinctly and could only be recovered shortly after spray. Pasture environments with exposure to sun and rain, seem to be very detrimental to the fungus, thus suspensions which provide fungus with protection or more resistant isolates to these should be looked for. In order to achieve high fungal efficacy against tick under field conditions, accurate laboratory assays, optimization of application strategy and knowledge of interactions between fungal strains and environmental factors are warranted., (Copyright © 2011 Elsevier B.V. All rights reserved.)

The purpose of this study was to evaluate the setting time and the thermal expansion coefficient of 2 endodontic cements, MTA-Angelus and a novel cement called CER. The setting time was determined in accordance to ANSI/ADA specifications no. 57. Three samples of 10 mm diameter and 2 mm thickness were prepared for each cement. The thermal expansion measurements were performed by strain gauge technique. Four samples of each cement were prepared using silicone rings of 5 mm diameter and 2 mm thickness. The data were analyzed statistically using the Student t test. The setting time obtained for the MTA-Angelus and CER cements was 15 (SD 1) min and 7 (SD 1) min, respectively. The linear coefficient of thermal expansion was 8.86 (SD 0.28) microstrain/ degrees C for MTA-Angelus and 11.76 (SD 1.20) microstrain/ degrees C for CER. The statistical analysis showed significant difference (P < .05) in the setting time and linear coefficient of thermal expansion between the 2 cements. The CER cement has a coefficient of expansion similar to dentin, which could contribute to a decrease of microleakage degree.

The relationships among anthropometric variables, dietary nutrients, and plasma steroid, polypeptide, and binding-protein hormone concentrations were investigated in 24 Seventh-day Adventist postmenopausal women, 12 vegetarian (SV) and 12 nonvegetarian (SNV). Fasting blood and 7-d dietary intake information were collected. SVs consumed significantly more crude and dietary fiber and fewer saturated fatty acids than did SNVs. The thigh and sum of three skinfold-thickness measurements were significantly greater for SNVs than for SVs. Plasma concentrations of estradiol-17 beta were significantly lower in SVs than in SNVs. Significant relationships were observed for the combined groups (SV and SNV) between estradiol-17 beta and triceps and suprailiac skinfold thickness and body fat. Plasma concentrations of estradiol-17 beta of the combined groups revealed a significant negative relationship between their crude and dietary fiber intakes. Further study delineating the effects of adiposity and dietary nutrients on basal concentrations of sex hormones is warranted.

The purpose of this study was to investigate nutrient intakes of Seventh-Day Adventist elderly women who were similar in many demographic and life-style factors except for choice of diet. Twenty-three vegetarian and 14 non-vegetarian elderly women (mean +/- standard error ages 72.2 +/- 1.3 and 71.1 +/- 1.4 years, respectively) were recruited on the basis of several selection criteria, including race, religion, education, geographic area, Quetelet index, self-reported absence of major chronic disease and use of medications, and physical activity. Average years +/- SE of adherence to dietary regimens were 47.0 +/- 2.9 and 71.2 +/- 1.4 in the vegetarian and non-vegetarian groups, respectively. Results from analysis of 7-day food records showed that vegetarians consumed significantly less cholesterol, saturated fatty acids, and caffeine but more carbohydrate, dietary fiber, magnesium, vitamins E and A, thiamin, pantothenic acid, copper, and manganese than non-vegetarians (p less than .05). On the basis of group means, 67% of the Recommended Dietary Allowance was met for all nutrients except zinc and vitamin D in both groups, and vitamins B-6, folacin, and vitamin E in the non-vegetarians. Compared with non-vegetarians, vegetarians had significantly lower serum glucose (5.18 +/- 0.11 vs. 4.65 +/- 0.09 mmol/L), low-density-lipoprotein cholesterol (4.08 +/- 0.25 vs. 3.34 +/- 0.19 mmol/L), and total cholesterol levels (6.46 +/- 0.27 vs. 5.62 +/- 0.21 mmol/L) (p less than .05). In summary, when healthy elderly vegetarian women were compared with closely matched non-vegetarian peers, the vegetarian diet was associated with improved nutrient intake and associated reductions in blood glucose and lipid levels.