Development of a bioadhesive nanoformulation with Glycyrrhiza glabra L. extract against Candida albicans

Abstract

Glycyrrhiza glabra L. is considered an important source of bioactive compounds. This study aimed at the development of an efficient solution for the treatment of oral candidiasis. Several extracts of Glycyrrhiza glabra L. were prepared using different solvents and their potential in vitro antifungal activity was assessed. Ethanolic extracts showed the most promising results against C. albicans. This extract was incorporated into mucoadhesive nanoparticles (PLA, PLGA and alginate), which were further included in an oral gel, an oral film and a toothpaste, respectively. The results showed that nanoparticles were successfully produced, presenting a mean size among 100–900?nm with high encapsulation efficiency. In vitro studies showed that the most bioadhesive formulation was the oral film with extract-loaded PLGA nanoparticles, followed by the toothpaste with extract-loaded alginate nanoparticles and the oral gel with extract-loaded PLA nanoparticles.     

New Insights into the Circadian Rhythm of Acute Myocardial Infarction in Subgroups

The aim of this study was to determine the existence of the circadian rhythm (CR) in the onset of acute myocardial infarction (AMI) in different patient subgroups. Information was collected about 41,244 infarctions from the database of the ARIAM (Analysis of Delay in AMI) Spanish multicenter study. CR in AMI were explored in subgroups of cases categorized by age, gender, previous ischemic heart disease (PIHD), outcome in coronary care unit, infarction electrocardiograph (ECG) characteristics (Q wave or non‐Q wave), and location of AMI. Cases were classified according to these variables in the different subgroups. To verify the presence of CR, a simple test of equality of time series based on the multiple‐sinusoid (24, 12, and 8 h periods) cosinor analysis was developed. For the groups as a whole, the time of pain onset as an indicator of the AMI occurrence showed a CR (p<0.0001), with a morning peak at 10:10 h. All the analyzed subgroups also showed CR. Comparison between subgroups showed significant differences in the PIHD (p<0.01) and infarction ECG characteristics (p<0.01) groups. The CR of the subgroup with Q‐wave infarction differed from that of non‐Q wave subgroup (p<0.01) when the patients had PIHD (23% in Q wave infarction vs. 39.2% in non‐Q wave). AMI onset followed a CR pattern, which is also observed in all analyzed subgroups. Differences in the CR according to the Q/non‐Q wave infarction characteristics could be determined by PIHD. The cosinor model fit with three components (24, 12, and 8 h periods) showed a higher sensitivity than the single 24 h period analysis.     

Health applications of bioactive compounds from marine microalgae

Marine microalgae and cyanobacteria are very rich in several chemical compounds and, therefore, they may be used in several biological applications related with health benefits, among others. This review brings the research up-to-date on the bioactive compounds produced by marine unicellular algae, directly or indirectly related to human health. It covers and goes through the most studied applications of substances such as PUFA, sterols, proteins and enzymes, vitamins and pigments, in areas so diverse as human and animal nutrition, therapeutics, and aquaculture. The great potential of marine microalgae and the biocoumpounds they produce are discussed in this review.     

Anthropogenic subsidies mitigate environmental variability for insular rodents

The exogenous input of nutrients and energy into island systems fuels a large array of consumers and drives bottom-up trophic cascades in island communities. The input of anthropogenic resources has increased on islands and particularly supplemented non-native consumers with extra resources. We test the hypothesis that the anthropogenic establishments of super-abundant gulls and invasive iceplants Carpobrotus spp. have both altered the dynamics of an introduced black rat Rattus rattus population. On Bagaud Island, two habitats have been substantially modified by the anthropogenic subsidies of gulls and iceplants, in contrast to the native Mediterranean scrubland with no anthropogenic inputs. Rats were trapped in all three habitats over two contrasting years of rainfall patterns to investigate: (1) the effect of anthropogenic subsidies on rat density, age-ratio and growth rates, and (2) the role of rainfall variability in modulating the effects of subsidies between years. We found that the growth rates of rats dwelling in the non-subsidized habitat varied with environmental fluctuation, whereas rats dwelling in the gull colony maintained high growth rates during both dry and rainy years. The presence of anthropogenic subsidies apparently mitigated environmental stress. Age ratio and rat density varied significantly and predictably among years, seasons, and habitats. While rat densities always peaked higher in the gull colony, especially after rat breeding in spring, higher captures of immature rats were recorded during the second year in all habitats, associated with higher rainfall. The potential for non-native rats to benefit from anthropogenic resources has important implications for the management of similar species on islands.     

Mitogen-activated Protein Kinase Signaling Mediates Phosphorylation of Polycomb Ortholog Cbx7

Cbx7 is one of five mammalian orthologs of the Drosophila Polycomb. Cbx7 recognizes methylated lysine residues on the histone H3 tail and contributes to gene silencing in the context of the Polycomb repressive complex 1 (PRC1). However, our knowledge of Cbx7 post-translational modifications remains limited. Through combined biochemical and mass spectrometry approaches, we report a novel phosphorylation site on mouse Cbx7 at residue Thr-118 (Cbx7T118ph), near the highly conserved Polycomb box. The generation of a site-specific antibody to Cbx7T118ph demonstrates that Cbx7 is phosphorylated via MAPK signaling. Furthermore, we find Cbx7T118 phosphorylation in murine mammary carcinoma cells, which can be blocked by MEK inhibitors. Upon EGF stimulation, Cbx7 interacts robustly with other members of PRC1. To test the role of Cbx7T118 phosphorylation in gene silencing, we employed a RAS-induced senescence model system. We demonstrate that Cbx7T118 phosphorylation moderately enhances repression of its target gene p16. In summary, we have identified and characterized a novel MAPK-mediated phosphorylation site on Cbx7 and propose that mitogen signaling to the chromatin template regulates PRC1 function.     

Nontuberculous mycobacteria in respiratory samples from patients with pulmonary tuberculosis in the state of Rond?nia, Brazil

The main cause of pulmonary tuberculosis (TB) is infection with Mycobacterium tuberculosis (MTB). We aimed to evaluate the contribution of nontuberculous mycobacteria (NTM) to pulmonary disease in patients from the state of Rondônia using respiratory samples and epidemiological data from TB cases. Mycobacterium isolates were identified using a combination of conventional tests, polymerase chain reaction-based restriction enzyme analysis of hsp65 gene and hsp65 gene sequencing. Among the 1,812 cases suspected of having pulmonary TB, 444 yielded bacterial cultures, including 369 cases positive for MTB and 75 cases positive for NTM. Within the latter group, 14 species were identified as Mycobacterium abscessus, Mycobacterium avium, Mycobacterium fortuitum, Mycobacterium intracellulare, Mycobacterium gilvum, Mycobacterium gordonae, Mycobacterium asiaticum, Mycobacterium tusciae, Mycobacterium porcinum, Mycobacterium novocastrense, Mycobacterium simiae, Mycobacterium szulgai, Mycobacterium phlei and Mycobacterium holsaticum and 13 isolates could not be identified at the species level. The majority of NTM cases were observed in Porto Velho and the relative frequency of NTM compared with MTB was highest in Ji-Paraná. In approximately half of the TB subjects with NTM, a second sample containing NTM was obtained, confirming this as the disease-causing agent. The most frequently observed NTM species were M. abscessus and M. avium and because the former species is resistant to many antibiotics and displays unsatisfactory cure rates, the implementation of rapid identification of mycobacterium species is of considerable importance.     

High-efficiency Agrobacterium-mediated transformation in Quercus robur: selection by use of a temporary immersion system and assessment by quantitative PCR

An efficient protocol for genetic transformation of somatic embryos of Quercus robur by selection in a temporary immersion system is reported. The transformation frequency was 5 times higher than achieved by conventional culture on semi-solid medium, ranging between 6 and 26 % for the four genotypes evaluated. Clumps of globular or torpedo somatic embryos were precultured for 7–10 days, inoculated with Agrobacterium tumefaciens strain EHA105:p35SGUSINT and cocultivated for 4 days before being cultured for 4 weeks on semi-solid selection medium supplemented with 25 mg L^?1 kanamycin. Explants were transferred to RITA^® bioreactors and subjected to a two-step selection protocol involving immersion in liquid medium supplemented with 25 mg L^?1 kanamycin, for 18 weeks, and then with 75 mg L^?1 kanamycin. Putatively transformed explants appeared after serial transfer to selection medium over 12–16 weeks. The presence of neomycin phosphotransferase II and β-glucuronidase genes in the plant genome was confirmed by histochemical and molecular analysis, and the copy number was determined by Southern blotting and real-time quantitative polymerase chain reaction. Transformed somatic embryos were germinated and transferred to soil for acclimatization, approximately 8 months after inoculation of the original tissue with bacteria. As the limiting factor for recovery of plants from oak embryogenic lines is the low embryo conversion rate, axillary shoot lines were established from transformed germinated embryos. Transformed embryos and shoots were cultured in medium with or without kanamycin and the responses to several morphogenetic processes (recovery after cryopreservation, germination, shoot proliferation, and rooting) were evaluated.     

Opportunistic feeding responses of the Yellow-legged Gull Larus michahellis to accessibility of refuse dumps

Capsule The gulls adjust their diet composition and diversity according to refuse dump accessibility.

Aims To examine the influence of the accessibility of open-air refuse dumps on the pre-laying diet of the adult Yellow-legged Gull.

Methods We studied six colonies settled on six rocky islands off the southeastern coast of France. A comparative study of the diet of breeding adults from the six colonies was made through pellet analysis (a total of 848 pellets). We determined the main foraging habitat used (refuse dumps, terrestrial habitats, marine habitat) and the number of foraging habitats used simultaneously (one, two or three), from which we deduced the mean diet diversity.

Results Refuse dumps were consistently the main foraging habitat (evidence in 53–74% of pellets) for the six colonies, even when refuse dump accessibility was low. The majority of pellets contained materials from two simultaneous foraging habitats (evidence in 50–64% of pellets). We demonstrated the influence of a gradient of refuse dump accessibility in terms of adjustment of the pre-laying adult's diet. Indeed, high refuse dump accessibility leads to a poorly diversified diet dominated by refuse. In contrast, when refuse dump accessibility is low, Yellow-legged Gulls broaden their trophic niche, with an increased exploitation of alternative foraging habitats, such as terrestrial habitats.

Conclusion These results show the species' opportunistic feeding and high adaptability, two parameters which need to be known to foresee the consequences on population dynamics, feeding and predatory behaviour of a sudden and severe food shortage, for example due to closure of open-air refuse dumps.     

Bacterial community composition of anthropogenic biochar and Amazonian anthrosols assessed by 16S rRNA gene 454 pyrosequencing

Biochar (BC) is a common minor constituent of soils and is usually derived from the burning of wood materials. In the case of Amazonian dark earth (ADE) soils, the increased amount of this material is believed to be due to anthropogenic action by ancient indigenous populations. In this study, we use 16S rRNA gene pyrosequencing to assess the bacterial diversity observed in the BC found in ADEs as well as in the dark earth itself and the adjacent Acrisol. Samples were taken from two sites, one cultivated with manioc and one with secondary forest cover. Analyses revealed that the community structure found in each sample had unique features. At a coarse phylogenetic resolution, the most abundant phyla in all sequence libraries were Actinobacteria, Acidobacteria, Verrucomicrobia and Proteobacteria that were present in similar relative abundance across all samples. However, the class composition varied between them highlighting the difference between the Acrisol and the remaining samples. This result was also corroborated by the comparison of the OTU composition (at 97 % identity). Also, soil coverage has shown an effect over the community structure observed in all samples. This pattern was found to be significant through unweighted UniFrac as well as P tests. These results indicate that, although the ADEs are found in patches within the Acrisols, the contrasting characteristics found between them led to the development of significantly different communities.     

QTL mapping of egg albumen quality in egg layers

Background

A fresh, good quality egg has a firm and gelatinous albumen that anchors the yolk and restricts growth of microbiological pathogens. As the egg ages, the gel-like structure collapses, resulting in thin and runny albumen. Occasionally thin albumen is found in a fresh egg, giving the impression of a low quality product. A mapping population consisting of 1599 F₂ hens from a cross between White Rock and Rhode Island Red lines was set up, to identify loci controlling albumen quality. The phenotype for albumen quality was evaluated by albumen height and in Haugh units (HU) measured on three consecutive eggs from each F₂ hen at the age of 40 weeks. For the fine-mapping analysis, albumen height and HU were used simultaneously to eliminate contribution of the egg size to the phenotype.

Results

Linkage analysis in a small population of seven half-sib families (668 F₂) with 162 microsatellite markers spread across 27 chromosomes revealed two genome-wide significant regions with additive effects for HU on chromosomes 7 and Z. In addition, two putative genome-wide quantitative trait loci (QTL) regions were identified on chromosomes 4 and 26. The QTL effects ranged from 2 to 4% of the phenotypic variance. The genome-wide significant QTL regions on chromosomes 7 and Z were selected for fine-mapping in the full set composed of 16 half-sib families. In addition, their existence was confirmed by an association analysis in an independent commercial Hy-Line pure line.

Conclusions

We identified four chicken genomic regions that affect albumen quality. Our results also suggest that genes that affect albumen quality act both directly and indirectly through several different mechanisms. For instance, the QTL regions on both fine-mapped chromosomes 7 and Z overlapped with a previously reported QTL for eggshell quality, indicating that eggshell membranes may play a role in albumen quality.