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Biosynthetic gold nanoparticles (bAuNPs) present a promising avenue for enhancing bio-compatibility and offering an economically and environmentally responsible alternative to traditional production methods, achieved through a reduction in the use of hazardous chemicals. While the potential of bAuNPs as anticancer agents has been explored, there is a limited body of research focusing on the crucial physicochemical conditions influencing bAuNP production. In this study, we aim to identify the optimal growth phase of Pseudomonas aeruginosa cultures that maximizes the redox potential and coordinates the formation of bAuNPs with increased efficiency. The investigation employs 2,6-dichlorophenolindophenol (DCIP) as a redox indicator. Simultaneously, we explore the impact of temperature, pH, and incubation duration on the biosynthesis of bAuNPs, with a specific emphasis on their potential application as antitumor agents. Characterization of the resulting bAuNPs is conducted using ATR-FT-IR, TEM, and UV-Vis spectroscopy. To gain insights into the anticancer potential of bAuNPs, an experimental model is employed, utilizing both non-neoplastic (HPEpiC) and neoplastic (PC3) epithelial cell lines. Notably, P. aeruginosa cultures at 9 h/OD600 = 1, combined with biosynthesis at pH 9.0 for 24 h at 58 °C, produce bAuNPs that exhibit smaller, more spherical, and less aggregated characteristics. Crucially, these nanoparticles demonstrate negligible effects on HPEpiC cells while significantly impacting PC3 cells, resulting in reduced viability, migration, and lower IL-6 levels. This research lays the groundwork for the development of more specialized, economical, and ecologically friendly treatment modalities. [ABSTRACT FROM AUTHOR]

Cutibacterium acnes (C. acnes) is a Gram-positive anaerobic facultative bacterium that is part of the human skin commensal microbiome. It colonizes various regions of the body, including the face, back, and chest. While typically a harmless commensal, under certain conditions, C. acnes can become pathogenic, leading to or promoting conditions such as acne vulgaris (AV), post-surgical infections, prostate cancer, and sarcoidosis. Current treatments for C. acnes infections often involve antibiotics, but the rise of antibiotic resistance has raised concerns. This review presents the virulence factors, clinical relevance, and current treatments of C. acnes, highlighting its association with AV, post-surgical infections, and other diseases. It also explores alternative innovative therapies such as phage therapy in development/research that are gaining prominence, with a growing focus on personalized medical approaches. To enhance C. acnes treatment while minimizing side effects and antibiotic prescription concerns, numerous clinical studies have been undertaken. These investigations span various pathological profiles and employ diverse strategies, such as utilizing bacterial extracts and compounds to restore healthy skin flora. The limitations and challenges of current and innovative treatments are also addressed, emphasizing the need for multidisciplinary strategies to combat C. acnes infections effectively. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa (PAO1) is an opportunistic pathogen, lethal in immunocompromised individuals. The clinical management of PAO1 infections still depends deeply on antibiotic therapy. However, this therapy has been alarmingly overpowered by growing bacterial resistance mechanisms over the years. One of these bacterial mechanisms is quorum sensing (QS). QS is involved in the production of biofilm, rhamnolipids and pyocyanin, among other factors. The present study aimed to study the effect of the mutations in the genes of rubredoxin (Rub A1 and Rub A2) and glutaredoxin (GLRx) in the production of virulence traits and susceptibility of PAO1 to the antibiotic ciprofloxacin (CIP) and to infection by a phage cocktail. Rub A1, Rub A2, and GLRx showed a decrease in the expression of genes lasI, lasR, mvfR, and rpsL when compared to the wild type, PAO1. Rub A1 and Rub A2 also showed a decrease in the expression of the gene pqsA, while the mutant GLRx showed an increase of over 200% in expression compared to PAO1. The biofilm produced by the mutants Rub A1, Rub A2, and GLRx increased more than 1.5 times in comparison to PAO1, with statistical significance (p < 0.0001). In the viability assay, the mutant strain Rub A2 was the most susceptible to ciprofloxacin in both concentrations tested (p < 0.0001). The production of proteases increased in the mutant strains when compared to PAO1 (p < 0.05). However, there was a decrease in the production of rhamnolipids and pyocyanins in the mutant strains. In the phage assay, we could perceive a reduction in the growth of the mutant strains when compared to PAO1. Additionally, after the addition of the phages, all the strains showed susceptibility to the phage assay (p < 0.0001), observed in the decrease in the absorbance values. These results may highlight the relevance of the genes Rub A1, Rub A2, and GLRX in the proliferation and treatment of infections with PAO1. Overall, this study gives preliminary insights into how gene expression may be helpful in strategies to overcome antibiotic resistance. [ABSTRACT FROM AUTHOR]

The objective of this work is to evaluate the influence of pomegranate peel extract (PPE) in the behavior of breast cell lines (epithelial and tumor type) and related oxidative metabolism. Fruit-based functional foods have been the target of increasing scientific research for their physiological and pathophysiological properties. Pomegranate (Punica granatum) is a suitable example with both prophylactic and medicinal effects. MCF-7 cell line from tumor breast carcinoma, and MCF-10A cell line from normal epithelial mammary gland were used and subjected to different concentrations of PPE, ranging from 1 to 5 mM of gallic acid equivalents (GAE). Viability, proliferation, mobility, and cytotoxicity assays were performed along with the quantification of antioxidant enzymes, namely, catalase, superoxide dismutase (SOD) and reduced (GSH) and oxidized (GSSG) glutathione. We observed a decrease in viability and proliferation of MCF-7 cells, at higher concentrations of PPE, with no influence in epithelial cells. Interestingly, in a concentration-dependent manner, PPE triggered a significant decrease in migration on both cell lines, with a more pronounced effect in breast cancer cell line. Regarding antioxidant enzyme activity, on tumor cells higher concentrations of PPE decreased catalase activity and significantly increased SOD activity. Regarding GSH and GSSG, we observed different expression levels between MCF-7 and MCF-10A, with MCF-7 presenting lower levels compared to MCF-10A. GSH/GSSG ratio was notably higher in MCF-7 at 5 mM GAE. PPE exhibits anti-tumor effects without significantly affecting normal epithelial cells. Our work strengthens the potential antitumoral effect of PPE by reducing MCF-7 cell viability and proliferation through the imbalance of antioxidant enzymes. [ABSTRACT FROM AUTHOR]

Simple Summary: This study characterises microplastics ingested by small cetaceans on the coast of Portugal. The intestine contents of 38 stranded cetaceans were processed in the laboratory to remove as much organic matter as possible from the samples and facilitate the detection of microplastics under a stereomicroscope. This study evaluated the possible influence of several biological and health variables (e.g., species, sex, body condition) on the amount of microplastics found in three small cetacean species, particularly on common dolphins, due to the larger number of available samples. Most of the analysed individuals had microplastics, with harbour porpoises revealing a significantly higher median number of microplastics than common dolphins, probably due to their different diets, use of habitat and feeding strategies. However, none of the other tested variables significantly influenced the number of microplastics in either all of the analysed species or in the common dolphin group. The relatively low numbers of microplastics found in the present study should not be enough to cause physical and chemical sublethal effects, although the potential effects of plastic-derived pollutants are not yet completely understood. Future monitoring of biota should rely on improved and standardised protocols for microplastic analyses. This study characterises microplastics in small cetaceans on the coast of Portugal and assesses the relationship between several biological variables and the amount of detected microplastics. The intestines of 38 stranded dead cetaceans were processed in the laboratory, with digestion methods adapted to the amount of organic matter in each sample. The influence of several biological and health variables (e.g., species, sex, body condition) on the amount of microplastics was tested in all analysed species and particularly in common dolphins, due to the larger number of available samples. Most of the analysed individuals had microplastics in the intestine (92.11%), with harbour porpoises revealing a significantly higher median number of microplastics than common dolphins, probably due to their different diets, use of habitat and feeding strategies. None of the other tested variables significantly influenced the number of microplastics. Moreover, the microplastics found should not be enough to cause physical or chemical sublethal effects, although the correlation between microplastic ingestion and plastic additive bioaccumulation in cetacean tissues requires further investigation. Future monitoring in biota should rely on improved and standardised protocols for microplastic analyses in complex samples to allow for accurate analyses of larger samples and spatio-temporal comparisons. [ABSTRACT FROM AUTHOR]

Gold nanoparticles (AuNPs) have garnered attention as a potential alternative to conventional antibiotics due to their innovative antibacterial properties. This study demonstrates the successful production of biosynthetic gold nanoparticles (bAuNPs) using Pseudomonas aeruginosa (P. aeruginosa) as spherical nanostructures at 58 °C for 24 h, under alkaline pH (9.0). The successful synthesis of bAuNPs was confirmed through UV-Vis spectroscopy, exhibiting a characteristic peak within the 500–600 nm wavelength range, and the evaluation of the main functional groups and morphology were stressed by Fourier Transform Infrared Spectroscopy (FT-IR) and Transmission Electron Microscopy (TEM), respectively. Subsequently, the synthesized bAuNPs were combined with low concentrations of ampicillin and evaluated against Methicillin-Susceptible Staphylococcus aureus (MSSA) and Methicillin-Resistant Staphylococcus aureus (MRSA) through the classical serial dilution method. This innovative approach holds the potential to address the escalating issue of antibiotic resistance, providing a viable and sustainable solution. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has disrupted daily life, impacting relationships, work, and education. This has led to increased stress, anxiety, and depression, along with altered sleep patterns and eating behaviors. Quarantine and isolation have worsened mental health, especially in children and the elderly, due to the loss of activities and physical contact. Sleep disorders and negative dreams perpetuate poor sleep quality, increasing the risk of health issues. Sedentary lifestyles and emotional effects contribute to unhealthy eating patterns and obesity, exacerbated by disrupted routines and limited outdoor activities. Addressing these challenges requires prioritizing mental health, promoting healthy sleep habits, and addressing obesity factors. The pandemic has profoundly affected human well-being, but resilience, mental health, sleep, and nutrition can enhance overall well-being and adaptability in the post-COVID era. This comprehensive opinion aims to raise awareness of the wide-ranging impacts of this pandemic on various aspects of human well-being and to emphasize the importance of implementing strategies that prioritize mental health, improve sleep habits, address eating behaviors, and foster resilience to navigate and thrive in the face of future challenges. [ABSTRACT FROM AUTHOR]

Simple Summary: The Iberian harbour porpoise is currently threatened by accidental captures in fisheries (bycatch). Because monitoring cetacean bycatch is particularly challenging, marine mammal stranding networks may provide important information. Between 2000 and 2020, 756 porpoises washed ashore (stranded) on Portuguese and Galician coastlines. The post-mortem analyses of stranded porpoises revealed that the most representative cause of stranding (46.98% of the analysed porpoises) was fishery interaction and another 10.99% was identified as probable fishery interaction. Combining this information with porpoise annual abundance estimates in Portugal available for the period between 2011 and 2015, an estimated average of 207 porpoises died each year due to bycatch in Portuguese waters alone. This estimate greatly surpassed the maximum annual number of porpoise strandings due to human interactions (22 porpoises) that were predicted to occur without negatively affecting the population in Portuguese waters. To prevent porpoise bycatch in Portugal and Spain, fishing effort management is needed and new activities at sea must be carefully considered. Moreover, appropriate measures directed at the conservation of the Iberian harbour porpoise are crucial to ensure the restoration and survival of the population. The Iberian harbour porpoise population is small and fisheries bycatch has been described as one of its most important threats. Data on harbour porpoise strandings collected by the Portuguese and Galician stranding networks between 2000 and 2020 are indicative of a recent mortality increase in the western Iberian coast (particularly in northern Portugal). Overall, in Portugal and Galicia, individuals stranded due to confirmed fishery interaction represented 46.98% of all analysed porpoises, and individuals stranded due to probable fishery interaction represented another 10.99% of all analysed porpoises. Considering the Portuguese annual abundance estimates available between 2011 and 2015, it was possible to calculate that an annual average of 207 individuals was removed from the population in Portuguese waters alone, which largely surpasses the potential biological removal (PBR) estimates (22 porpoises, CI: 12–43) for the same period. These results are conservative and bycatch values from strandings are likely underestimated. A structured action plan accounting for new activities at sea is needed to limit the Iberian porpoise population decline. Meanwhile, there is an urgent need for a fishing effort reorganization to directly decrease porpoise mortality. [ABSTRACT FROM AUTHOR]

Simple Summary: The Iberian porpoise inhabits the Atlantic coast of Portugal and Spain. The population is relatively small and there is a high number of individuals accidentally captured in fisheries. Using airplane surveys, we estimated that there were only 2254 porpoises overall between 2011 and 2015 in the coast of Portugal. The highest annual number of porpoises was recorded in 2013 (3207 individuals). However, in the following year, our study revealed that the population had been reduced approximately by half (when an increase in stranded individuals was also registered). The northern area of Portugal presented the most suitable habitat for the Iberian harbour porpoise, where coastal fisheries represent a particularly important socio-economic activity. Measures to decrease fishing effort are urgently needed as well as detailed information on seasonal Iberian harbour porpoises' use of space. The Iberian porpoise population is small and under potentially unsustainable removal by fisheries bycatch. Recently, a marine Site of Community Importance (SCI) was legally approved in Portugal, but no measures ensued to promote porpoise conservation. Information about porpoise abundance and distribution is fundamental to guide any future conservation measures. Annual aerial surveys conducted between 2011 and 2015 show a low overall porpoise abundance and density (2254 individuals; 0.090 ind/km2, CV = 21.99%) in the Portuguese coast. The highest annual porpoise estimates were registered in 2013 (3207 individuals, 0.128 ind/km2), followed by a sharp decrease in 2014 (1653 individuals, 0.066 ind/km2). The porpoise density and abundance estimated in 2015 remained lower than the 2013 estimates. A potential distribution analysis of the Iberian porpoise population was performed using ensembles of small models (ESMs) with MaxEnt and showed that the overall habitat suitability is particularly high in the Portuguese northern area. The analysis also suggested a different pattern in porpoise potential distribution across the study period. These results emphasize the importance of further porpoise population assessments to fully understand the spatial and temporal porpoise habitat use in the Iberian Peninsula as well as the urgent need for on-site threat mitigation measures. [ABSTRACT FROM AUTHOR]

The Pseudomonas aeruginosa is one of the bacteria that cause serious infections due to resistance to many antibiotics can be fatal in severe cases. Antimicrobial resistance is a global public health concern. To solve this problem, interest in phage therapy has revived; some studies are being developed to try to prove the effectiveness of this therapy. Thus, in this opinion article, several historical aspects are addressed as well some applications of phage therapy against P. aeruginosa. [ABSTRACT FROM AUTHOR]

Simple Summary: CTX-M β-lactamases are a growing group among extended-spectrum β-lactamases (ESBLs), not only in number, diversity, and functional kinetics. Until now, it has been well-accepted five main clusters within CTX-M β-lactamases. These canonical clusters are CTX-M-1, CTX-M-2, CTX-M-8, CTX-M-9, and CTX-M-25. In the present study, we propose a new sixth cluster, CTX-M-151. The production of extended-spectrum β-lactamases (ESBLs) is the main defense mechanism found in Gram negative bacteria. Among all the ESBLs, the CTX-M enzymes appear as the most efficient in terms of dissemination in different epidemiological contexts. CTX-M enzymes exhibit a striking plasticity, with a large number of allelic variants distributed in several sublineages, which can be associated with functional heterogeneity of clinical relevance. This observational analytical study provides an update of this family, currently with more than 200 variants described, from a phylogenetic, molecular, and structural point of view through homology in amino acid sequences. Our data, combined with described literature, provide phylogenetic and structural evidence of a new group. Thus, herein, we propose six groups among CTX-M enzymes: the already stablished CTX-M-1, CTX-M-2, CTX-M-8, CTX-M-9, and CTX-M-25 clusters, as well as CTX-M-151 as the new cluster. [ABSTRACT FROM AUTHOR]