Antimicrobial potential of Eucalyptus globulus against biofilms of Staphylococcus aureus isolated from bovine mastitis

Staphylococcus aureus are among the most common species isolated from bovine mastitis. The pathogenesis of this bacterium is facilitated by a number of virulence factors, including the ability to adhere to abiotic surfaces and/or host tissues often leading to biofilms formation. From the clinical perspective, the most important feature of Staphylococcus species biofilms is their high tolerance to the conventional antimicrobial therapy. So, the increasing number of bovine mastitis and the higher levels of Staphylococcus species resistance to traditional antimicrobial agents are considered an important alert for the necessity to focus the future research on identification and development of new strategies to combat S. aureus mastitis. Recently, the interest in natural alternatives based on plant extracts has been rising. In addition to their health benefits, their antimicrobial potential has been increasingly reported. Taking this into consideration, the evaluation of hydromethanolic extracts of E. globulus against S. aureus biofilms was tested and compared with penicillin, one of the antibiotics most often used in the treatment of cattle infections. All mastitis isolates tested were good-biofilm producers. As expected penicillin has demonstrated poor activity against S. aureus biofilms (<1 log reduction). However, E. globulus Labill was bactericidal, promoting a biofilm cell reduction of 2-3 log. Therefore, the present work showed the potential antimicrobial activity of E. globulus against S. aureus from bovine mastitis, namely in biofilm mode of growth and drew attention to its promising use as an alternative to penicillin

European Portuguese Adaptation of Glasgow Content of Thoughts Inventory (GCTI): Psychometric Characterization in Higher Education Students

Persistent cognitive activity is an important factor in disturbing sleep-onset both during bedtime and when attempting to get back to sleep after nocturnal awakenings. One of the most specific self-report measures designed to assess this feature is the Glasgow Content of Thoughts Inventory (GCTI). In this study, we investigated the preliminary psychometric properties of GCTI in a large sample of higher education European Portuguese students (N = 2995). Our results suggest that there is evidence of good internal consistency (α = 0.93) and validity indicators. Moreover, we found an interpretable factorial structure comprising 5 correlated factors that needs to be confirmed in future studies. The European Portuguese version of the GCTI appears to be a reliable and valid instrument for measurement of sleep-onset disturbing cognitions

Bioactivity and phenolic characterization of different medicinal and aromatic plants

Introduction: Plants are widely used to treat various diseases and have been widely recognized as a rich source of phytochemicals with antimicrobial potential. In fact, plants have received considerable attention by researchers being their biological properties widely explored. Hypothesis and aims: Medicinal and aromatic plants are known to have a wide range of uses and health benefits, and should be exploited concerning their bioactivity. Therefore, the antimicrobial activity of Satureja montana L., Origanum majorana L., Allium schoenoprasum L. and Anethum graveolens L. were evaluated and its phytochemical composition was profiled. Methodology: The antimicrobial susceptibility of Gram-positive and Gram-negative bacteria to four decoction and hydroethanolic (80:20, v/v) extracts, obtained from medicinal and aromatic plants (S. montana , O. majorana , A. schoenoprasum and A. graveolens ), was assessed aiming to identify the active extracts and the most effective were then tested against biofilms. Furthermore, the decoctions were characterized in terms of phenolic compounds by HPLC-DAD-ESI/MSn. Results: Overall, S. montana and O. majorana extracts were the most effective against Gram-positive (Staphylococcus aureus , Enterococcus faecalis and Streptococcus dysgalactiae ) and Gram-negative (Klebsiella pneumonia and Pseudomonas aeruginosa ) bacteria, with decoction presenting the most pronounced effects. O. majorana and S. montana decoction, at minimum inhibitory concentrations, were significantly effective against planktonic cells of S. aureus ATCC 25923. Concerning biofilm cells, S. montana promoted a slight antimicrobial activity against S. aureus ATCC 25923. A total of twentyfour phenolic compounds (9 phenolic acids and 15 flavonoids glycosides) were identified in S. montana and O. majorana decoctions, being rosmarinic acid the main molecule in the extracts. Conclusion: This study confirmed the bioactive potential of the medicinal and aromatic herbs, being S. montana and O. majorana decoction extracts those that showed the most promising applicability for the development of novel formulations with antimicrobial properties.info:eu-repo/semantics/publishedVersio

Designing silk fibroin-based matrices with ionic liquids for tissue engineering strategies using human adipose stem cells

Silk (SF) is an attractive biomaterial to be used in tissue engineering applications because of its excellent mechanical properties and biocompatibility [1, 2]. In this work, the cellular response of silk hydrogels produced through dissolution of this protein in ionic liquids (ILs) was investigated. For that, degummed fibers obtained from the cocoons of mulberry silkworm (Bombyx mori) were dissolved in an IL and the solution was gelified in ethanol, followed by IL removal from gels using soxhlet extraction. The fabricated hydrogels were characterized biochemically and biophysically by detecting amino acid composition, FTIR, SEM and mechanical testing (DMA). For in vitro assessment, human adipose stem cells (hASCs) were seeded in the hydrogels and cultured for different time periods. The resulting hydrogels have a rubbery consistency, homogeneous surface and viscoelastic behavior. Additionally, no differences on amino acid composition were found, indicating that the silk composition was kept. Confocal images confirmed cell attachment and alignment of actin filaments within the hydrogel matrix with well-develop nuclei. The MTS assay demonstrated the metabolic activity of hASCs in contact with hydrogels up to 28 days. Furthermore, the results of DNA quantification showed that hASCs are able to proliferate during studied period. These results indicated that (i) the efficiency of IL removal resulted in hydrogels with minimal cytotoxicity; and (ii) positive cellular response of the materials surface for the adhesion and proliferation of hASCs. SEM observations corroborated with the results obtained from MTS and DNA suggested that cells are able to migrate at different levels within the structure. These findings indicated that silk hydrogels produced using ILs may be potential candidates for tissue engineering strategies, namely cartilage regeneration

An activating mutation in the CRHR1 gene is rarely associated with pituitary-dependent hyperadrenocorticism in poodles

OBJECTIVES: Pituitary-dependent hyperadrenocorticism is the most common cause of naturally occurring hypercortisolism in dogs. CRHR1 expression in human and dog corticotrophinomas suggested that this gene affects pituitary tumorigenesis. The present study aimed to investigate mutations in the CRHR1 coding region in poodles with pituitary-dependent hyperadrenocorticism. METHODS: Fifty poodles with pituitary-dependent hyperadrenocorticism and 50 healthy poodles were studied. Genomic DNA was amplified by PCR and analyzed by Sanger sequencing. RESULTS: The novel CRHR1 p.V97M mutation was identified in one dog. This valine residue, located in the amino-terminal extracellular domain, exhibits high affinity for its corticotropin-releasing hormone (CRH) ligand. Bioinformatic analysis revealed structural rearrangements in the mutant protein, with a 17% increase in the surface binding affinity between CRHR1 and CRH. In vitro functional studies showed that mutant CRHR1 induced higher ACTH secretion than the wild type after stimulation with human CRH. CONCLUSION: These results suggest that germline activating mutations in CRHR1 may be a rare cause of pituitary hyperadrenocorticism in poodles

Plant phenolic extracts as an effective strategy to control Staphylococcus aureus, the dairy industry pathogen

Staphylococcus aureus is one of the most common contagious mastitis pathogens. Bovine mastitis is considered an important reservoir for dairy industry contamination, and therefore to ensure S. aureus control has gained a pivotal importance. Natural matrices present multiple biological effects, being its antimicrobial potential increasingly reported. Thus, the present study aims to assess the antibacterial activity of several methanol:water extracts, obtained from plants, against Staphylococcus aureus. Moreover, the most effective extract was characterized in terms of phenolic compounds, by using high performance liquid chromatography coupled to diode array and mass spectrometer detectors. Among the tested extracts, Eucalyptus globulus was the most effective against all tested S. aureus strains, followed by Juglans regia and Foeniculum vulgare. Inhibition halos of the plant extracts varied between 8.0-16.0 mm, excepting for F. vulgare in which two evident halos were observed: one with growth inhibition (5.0-7.0 mm) and a second one with visible cell density reduction (13.0-14.0 mm). Susceptibility assays evidenced that E. globulus extract exerted the highest antibacterial activity (MICs=0.195-0.39 mg/mL), being effective against all the tested strains. Among the phenolic compounds identified in this extract, gallotannins, ellagic acid glycoside, and quercetin derivatives, were the most abundant; and therefore, may exert a positive and contributive effect to the observed antibacterial effect. Overall, the use of plant extracts to control bovine mastitis caused by S. aureus is a promising solution that could contribute to the reduction of the occurrence of dairy food industry contaminations, providing considerable benefits to agro-industries on the formulation of high-quality and safety dairy products.This study was supported by the Portuguese Foundation for Science and Technology (FCT) (grant number SFRH/BPD/84488/2012) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by European Regional Development Fund under the scope of Norte2020 − Programa Operacional Regional do Norte, as also Pest-OE/AGR/UI0690/2013 to CIMO. The authors are also grateful to the Interreg España-Portugal for financial support through the project 0377_Iberphenol_6_E and to Ana Maria Carvalho for the collection and identification of the wild samples, chemically characterized in previous studies.info:eu-repo/semantics/publishedVersio

Microglial Sirtuin 2 shapes long-term potentiation in hippocampal slices

Copyright © 2020 Sa de Almeida, Vargas, Fonseca-Gomes, Tanqueiro, Belo, Miranda-Lourenço, Sebastião, Diógenes and Pais. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.Microglial cells have emerged as crucial players in synaptic plasticity during development and adulthood, and also in neurodegenerative and neuroinflammatory conditions. Here we found that decreased levels of Sirtuin 2 (Sirt2) deacetylase in microglia affects hippocampal synaptic plasticity under inflammatory conditions. The results show that long-term potentiation (LTP) magnitude recorded from hippocampal slices of wild type mice does not differ between those exposed to lipopolysaccharide (LPS), a pro-inflammatory stimulus, or BSA. However, LTP recorded from hippocampal slices of microglial-specific Sirt2 deficient (Sirt2-) mice was significantly impaired by LPS. Importantly, LTP values were restored by memantine, an antagonist of N-methyl-D-aspartate (NMDA) receptors. These results indicate that microglial Sirt2 prevents NMDA-mediated excitotoxicity in hippocampal slices in response to an inflammatory signal such as LPS. Overall, our data suggest a key-protective role for microglial Sirt2 in mnesic deficits associated with neuroinflammation.This study was supported by Santa Casa da Misericórdia de Lisboa (MB37-2017), GAPIC Research Program of the University of Lisbon Medical School (n° 2014002 and n° 2015028) and the following doctoral grants: PD/BD/128091/2016, SFRH/BD/118238/2016, PD/BD/114337/2016, and PD/BD/1144- 41/2016.info:eu-repo/semantics/publishedVersio

Silk hydrogels from non-mulberry and mulberry silkworm cocoons processed with ionic liquids

Matrices based on silk fibroin from the non-mulberry silkworm Antheraea mylitta and the mulberry silkworm Bombyx mori have demonstrated good applicability in regenerative medicine. However, the cocoons of A. mylitta are underutilized in part due to their lack of solubility in traditional organic solvents. Therefore, the present work investigates the solubilization and processing of degummed fibers obtained from the cocoons of both silkworm species into hydrogels using ionic liquids (ILs). The developed hydrogels exhibited a rubbery consistency, viscoelastic behavior and rapid degradation in the presence of protease XIV. Scanning electron and confocal microscopy images suggest that human adipose stem cells (hASCs) are able to adhere to and migrate at different levels within the hydrogel structures. Moreover, the MTS assay demonstrated the maintenance of cell metabolic activity for up to 28days, while DNA quantification showed that hASCs were able to proliferate on the seeded hydrogels. The findings indicate that complete IL removal from the fabricated hydrogels results in a positive hASCs cellular response. Thus the present approach provides a unique opportunity to broaden the processability and application of silk fibroin obtained from A. mylitta cocoons for regenerative medicine, namely cartilage regeneration.The authors acknowledge financial support from the Portuguese Foundation for Science and Technology (Grants SFRH/BPD/45307/2008 and SFRH/BD/64070/2009), the Fundo Social Europeu, and the Programa Diferencial de Potencial Humano. This work was partially supported by the FEDER through POCTEP 0330_IBERO-MARE_1_P and also by the Department of Biotechnology, Government of India. S.C.K. is grateful to R.L.R. and S.S.S. for their excellent hospitality during his stay at the 3B's laboratory, Guimaraes, Portugal. R.L.R. also offers his sincere thanks to S.C.K. for providing hospitality during his short visits to his laboratory in the Indian Institute of Technology, Kharagpur

Inheritance of DNA Transferred from American Trypanosomes to Human Hosts

Interspecies DNA transfer is a major biological process leading to the accumulation of mutations inherited by sexual reproduction among eukaryotes. Lateral DNA transfer events and their inheritance has been challenging to document. In this study we modified a thermal asymmetric interlaced PCR by using additional targeted primers, along with Southern blots, fluorescence techniques, and bioinformatics, to identify lateral DNA transfer events from parasite to host. Instances of naturally occurring human infections by Trypanosoma cruzi are documented, where mitochondrial minicircles integrated mainly into retrotransposable LINE-1 of various chromosomes. The founders of five families show minicircle integrations that were transferred vertically to their progeny. Microhomology end-joining of 6 to 22 AC-rich nucleotide repeats in the minicircles and host DNA mediates foreign DNA integration. Heterogeneous minicircle sequences were distributed randomly among families, with diversity increasing due to subsequent rearrangement of inserted fragments. Mosaic recombination and hitchhiking on retrotransposition events to different loci were more prevalent in germ line as compared to somatic cells. Potential new genes, pseudogenes, and knockouts were identified. A pathway of minicircle integration and maintenance in the host genome is suggested. Thus, infection by T. cruzi has the unexpected consequence of increasing human genetic diversity, and Chagas disease may be a fortuitous share of negative selection. This demonstration of contemporary transfer of eukaryotic DNA to the human genome and its subsequent inheritance by descendants introduces a significant change in the scientific concept of evolutionary biology and medicine