Metabolic Activity Research Articles

Chemical composition, cytotoxicity, antimicrobial, antibiofilm, and anti-quorum sensing potential of Mentha Piperita essential oil against the oral pathogen Streptococcus mutans

ABSTRACT Dental caries is a highly prevalent oral disease affecting billions of individuals globally. The disease occurs chemically as a result of breakdown of the tooth surface attributed to metabolic activity in colonizing biofilm. Biofilms, composed of exopolysaccharides and proteins, protect bacteria like Streptococcus mutans, which is notable for its role in tooth decay due to its acid-producing abilities. While various antimicrobial agents may prevent biofilm formation, these drugs often produce side effects including enamel erosion and taste disturbances. This study aimed to examine utilization of the Mentha piperita essential oil as a potential antibiofilm activity agent against S. mutans. M. piperita oil significantly (1) reduced bacterial biofilm, (2) exhibited a synergistic effect when combined with chlorhexidine, and (3) did not induce cell toxicity. Chemical analysis identified the essential oil with 99.99% certainty, revealing menthol and menthone as the primary components, constituting approximately 42% and 26%, respectively. Further, M. piperita oil eradicated preformed biofilms and inhibited biofilm formation at sub-inhibitory concentrations. M. piperita oil also interfered with bacterial quorum sensing communication and did not produce any apparent cell toxicity in immortalized human keratinocytes (HaCaT). M. piperita represented an alternative substance for combating S. mutans and biofilm formation and a potential combination option with chlorhexidine to minimize side effects. An in-situ performance assessment requires further studies.

Assessment of fecal bacterial viability and diversity in fresh and frozen fecal microbiota transplant (FMT) product in horses

BackgroundCurrently, lack of standardization for fecal microbiota transplantation (FMT) in equine practice has resulted in highly variable techniques, and there is no data on the bacterial metabolic activity or viability of the administered product. The objectives of this study were to compare the total and potentially metabolically active bacterial populations in equine FMT, and assess the effect of different frozen storage times, buffers, and temperatures on an equine FMT product. Fresh feces collected from three healthy adult horses was subjected to different storage methods. This included different preservation solutions (saline plus glycerol or saline only), temperature (-20 °C or -80 °C), and time (fresh, 30, 60, or 90 days). Samples underwent DNA extraction to assess total bacterial populations (both live and dead combined) and RNA extraction followed by reverse transcription to cDNA as a proxy to assess viable bacteria, then 16s rRNA gene amplicon sequencing using the V1-V2 region.ResultsThe largest difference in population indices and taxonomic composition at the genus level was seen when evaluating the results of DNA-based (total) and cDNA-based (potentially metabolically active) extraction method. At the community level, alpha diversity (observed species, Shannon diversity) was significantly decreased in frozen samples for DNA-based analysis (P < 0.05), with less difference seen for cDNA-based sequencing. Using DNA-based analysis, length of storage had a significant impact (P < 0.05) on the bacterial community profiles. For potentially metabolically active populations, storage overall had less of an effect on the bacterial community composition, with a significant effect of buffer (P < 0.05). Individual horse had the most significant effect within both DNA and cDNA bacterial communities.ConclusionsFrozen storage of equine FMT material can preserve potentially metabolically active bacteria of the equine fecal microbiome, with saline plus glycerol preservation more effective than saline alone. Larger studies are needed to determine if these findings apply to other individual horses. The ability to freeze FMT material for use in equine patients could allow for easier clinical use of fecal transplant in horses with disturbances in their intestinal microbiome.

Metabolic profiling and enzyme inhibitory activity of the essential oil of citrus aurantium fruit peel

BackgroundBitter orange (Citrus aurantium) is a fruiting shrub native to tropical and subtropical countries around the world and cultivated in many regions due to its nutraceutical value. The current study investigated the metabolic profiling and enzyme inhibitory activities of volatile constituents derived from the C. aurantium peel cultivated in Egypt by three different extraction methods.MethodsThe volatile chemical constituents of the peel of C. aurantium were isolated using three methods; steam distillation (SD), hydrodistillation (HD), and microwave-assisted hydrodistillation (MAHD), and then were investigated by GC-MS. The antioxidant potential was evaluated by different assays such as DPPH, ABTS, FRAP, CUPRAC, and phosphomolybdenum and metal chelating potential. Moreover, the effect of enzyme inhibition of the three essential oils was tested using BChE, AChE, tyrosinase, glucosidase, as well as amylase assays.ResultsA total of six compounds were detected by GC/MS analysis. The major constituent obtained by all three extraction methods was limonene (98.86% by SD, 98.68% by HD, and 99.23% by MAHD). Differences in the composition of the compounds of the three oils were observed. The hydrodistillation technique has yielded the highest number of compounds, notably two oxygenated monoterpenes: linalool (0.12%) and α-terpineol acetate (0.1%).ConclusionIn our study differences in the extraction methods of C. aurantium peel oils resulted in differences in the oils’ chemical composition. Citrus essential oils and their components showed potential antioxidant, anticholinesterase, antimelanogenesis, and antidiabetic activities. The presence of linalool and α-terpineol acetate may explain the superior activity observed for the oil isolated by HD in both radical scavenging and AChE inhibition assays, as well as in the enzyme inhibition assays.

Modulating efficacy and cytotoxicity of lipoamino fatty acid nucleic acid carriers using disulfide or hydrophobic spacers.

Double pH-responsive xenopeptides comprising polar ionizable succinoyl tetraethylene pentamine (Stp) motifs and lipophilic ionizable lipoamino fatty acids (LAFs) were recently found to efficiently transfect mRNA and pDNA at low doses. However, potency was often accompanied with cytotoxicity at higher doses. Insertion of bioreducible disulfide building blocks (ssbb) or non-reducible hydrophobic spacers between polar and apolar ionizable domains of LAF-Stp carriers should mitigate toxicity of xenopeptides. Carriers showed stable nucleic acid complexation and endosomal pH-dependent lytic activities, both of which were abolished after reductive cleavage of ssbb-containing carriers. For pDNA, U-shaped carriers with one Stp and two LAF units or bundle carriers with two Stps and four LAFs displayed highest potency. For mRNA, best transfection was achieved with bundle carriers with one Stp and four LAFs. Both the ssbb and hydrophobic spacer containing analogs displayed improved metabolic activity, reduced membrane damage, and improved cell growth. The ssbb carriers were most beneficial regarding living cell count and low apoptosis rates. Mechanistically, inserted spacers decelerated the transfection kinetics and altered the requirement of endosomal protonation. Overall, mRNA and pDNA carriers with improved biocompatibility have been designed, with their high potency illustrated in transfection of various cell lines including low passage number colon carcinoma cells.

Isolation and characterisation of two epithelial-like cell lines from the gills of Chrysophrys auratus (Australasian snapper)and Oncorhynchus tshawytscha (Chinook salmon) and their use in aquatic toxicology.

In vitro gill models are becoming increasingly important in aquatic toxicology, yet the fish gill invitrome is underrepresented, encompassing approximately 0.1% of extant species. Here, we describe the establishment and characterisation of two gill-derived, epithelial-like cell lines isolated from fish species of significant importance to New Zealand: Chrysophrys auratus (Australasian snapper) and Oncorhynchus tshawytscha (Chinook salmon). Designated CAgill1PFR (Chrysophrys auratus, gill 1, Plant & Food Research) and OTgill1PFR (Oncorhynchus tshawytscha, gill 1, Plant & Food Research), these cell lines have each been passaged greater than each 70 times over several years and are considered spontaneously immortalised. Both cell lines required serum for growth and exhibited differential responses to basal media formulations. CAgill1PFR was sensitive to low temperatures (4°C) but replicated at high temperatures (30°C), whereas OTgill1PFR was sensitive to high temperatures but remained viable at low temperatures, mirroring the natural environment of their host species. Immunostaining revealed expression of epithelial cell markers cytokeratin and E-cadherin, alongside positivity for the mesenchymal cell marker, vimentin. CAgill1PFR was more sensitive to the environmental toxin 3,4 dichloroaniline than OTgill1PFR through measurements of metabolic activity, membrane integrity, and lysosomal function. Furthermore, CAgill1PFR produced less CYP1A activity, indicative of ongoing biotransformation processes, in response to beta-naphthoflavone than OTgill1PFR. These cell lines expand the toolbox of resources and emphasise the need for species-specific aquatic toxicology research.

Optimizing bioremediation techniques for soil decontamination in a linguistic intuitionistic fuzzy framework

Bioremediation techniques, which harness the metabolic activities of microorganisms, offer sustainable and environmentally friendly approaches to contaminated soil remediation. These methods involve the introduction of specialized microbial consortiums to facilitate the degradation of pollutants, contribute to soil restoration, and mitigate environmental hazards. When selecting the most effective bioremediation technique for soil decontamination, precise and dependable decision-making methods are critical. This research endeavors to tackle the aforementioned concern by utilizing the tool of aggregation operators in the framework of the Linguistic Intuitionistic Fuzzy (LIF) environment. Linguistic Intuitionistic Fuzzy Sets (LIFSs) provide a robust framework for representing and managing uncertainties associated with linguistic expressions and intuitionistic assessments. Aggregation operators enrich the decision-making process by efficiently handling the intrinsic uncertainties, preferences, and priorities of MADM problems; as a consequence, the decisions produced are more reliable and precise. In this research, we utilize this concept to devise innovative aggregation operators, namely the linguistic intuitionistic fuzzy Dombi weighted averaging operator (LIFDWA) and the linguistic intuitionistic fuzzy Dombi weighted geometric operator (LIFDWG). We also demonstrate the critical structural properties of these operators. Additionally, we formulate novel score and accuracy functions for multiple attribute decision-making (MADM) problems within LIF knowledge. Furthermore, we develop an algorithm to confront the complexities associated with ambiguous data in solving decision-making problems in the LIF Dombi aggregation environment. To underscore the efficacy and superiority of our proposed methodologies, we adeptly apply these techniques to address the MADM problem concerning the optimal selection of a bioremediation technique for soil decontamination. Moreover, we present a comparative evaluation to delineate the authenticity and practical applicability of the recently introduced approaches relative to previously formulated techniques.

Interplay of the heart, spleen, and bone marrow in heart failure: the role of splenic extramedullary hematopoiesis.

Improvements in therapies for heart failure with preserved ejection fraction (HFpEF) are crucial for improving patient outcomes and quality of life. Although HFpEF is the predominant heart failure type among older individuals, its prognosis is often poor owing to the lack of effective therapies. The roles of the spleen and bone marrow are often overlooked in the context of HFpEF. Recent studies suggest that the spleen and bone marrow could play key roles in HFpEF, especially in relation to inflammation and immune responses. The bone marrow can increase production of certain immune cells that can migrate to the heart and contribute to disease. The spleen can contribute to immune responses that either protect or exacerbate heart failure. Extramedullary hematopoiesis in the spleen could play a crucial role in HFpEF. Increased metabolic activity in the spleen, immune cell production and mobilization to the heart, and concomitant cytokine production may occur in heart failure. This leads to systemic chronic inflammation, along with an imbalance of immune cells (macrophages) in the heart, resulting in chronic inflammation and progressive fibrosis, potentially leading to decreased cardiac function. The bone marrow and spleen are involved in altered iron metabolism and anemia, which also contribute to HFpEF. This review presents the concept of an interplay between the heart, spleen, and bone marrow in the setting of HFpEF, with a particular focus on extramedullary hematopoiesis in the spleen. The aim of this review is to discern whether the spleen can serve as a new therapeutic target for HFpEF.

Resistance to FOXM1 inhibitors in breast cancer is accompanied by impeding ferroptosis and apoptotic cell death.

Cancer treatments often become ineffective because of acquired drug resistance. To characterize changes in breast cancer cells accompanying development of resistance to inhibitors of the oncogenic transcription factor, FOXM1, we investigated the suppression of cell death pathways, especially ferroptosis, in FOXM1 inhibitor-resistant cells. We also explored whether ferroptosis activators can synergize with FOXM1 inhibitors and can overcome FOXM1 inhibitor resistance. In estrogen receptor-positive and triple-negative breast cancer cells treated with FOXM1 inhibitor NB73 and ferroptosis activators dihydroartemisinin and JKE1674, alone and in combination, we measured suppression of cell viability, motility, and colony formation, and monitored changes in gene and protein pathway expressions and mitochondrial integrity. Growth suppression of breast cancer cells by FOXM1 inhibitors is accompanied by increased cell death and alterations in mitochondrial morphology and metabolic activity. Low doses of FOXM1 inhibitor strongly synergize with ferroptosis inducers to reduce cell viability, migration, colony formation, and expression of proliferation-related genes, and increase intracellular Fe+2 and lipid peroxidation, markers of ferroptosis. Acquired resistance to FOXM1 inhibition is associated with increased expression of cancer stem-cell markers and proteins that repress ferroptosis, enabling cell survival and drug resistance. Notably, resistant cells are still sensitive to growth suppression by low doses of ferroptosis activators, effectively overcoming the acquired resistance. Delineating changes in viability and cell death pathways that can overcome drug resistance should be helpful in determining approaches that might best prevent or reverse resistance to therapeutic targeting of FOXM1 and ultimately improve patient clinical outcomes.

Tree age affects carbon sequestration potential via altering soil bacterial community composition and function

Among various factors related to the forest carbon pool, the tree stand age, which interacts with soil organic matter, decomposition rates, and microbial activity, is essential and cannot be disregarded. However, knowledge about how tree phases influence soil carbon sinks is not adequate. This study sampled Larix kaempferi (Japanese larch) plantations with different tree stand ages to investigate the temporal dynamics of soil carbon sink in the forest. Physiochemical analyses and high-throughput sequencing results further revealed the interactions of tree stands and their related rhizosphere microbiome. It was found that microbial composition and metabolic activity were significantly affected by different tree ages, whose structures gradually diversified and became more stable from young to mature forests. Many keystone taxa from the phyla Chloroflexi, Proteobacteria, Acidobacteriota, and Nitrospirota were found to be associated with carbon transformation processes. Interestingly, the carbon resource utilization strategies of microbial groups related to tree ages also differed, with near-mature forest soils showing better labile carbon degradation capacity, and mature forests possessing higher degradation potential of recalcitrant carbon. Age-altered tree growth and physiology were found to interact with its rhizosphere microbiome, which is the driving factor in the formation and stability of forest soil carbon. This study highlighted that the tree age-associated soil microbiomes, which provided insights into their effects on soil carbon transformation, were significant in enhancing the knowledge of carbon sequestration in L. kaempferi plantations.

Development of 3D Printable Gelatin Methacryloyl/Chondroitin Sulfate/Hyaluronic Acid Hydrogels as Implantable Scaffolds

The development of biomaterials tailored for various tissue engineering applications has been increasingly researched in recent years; however, stimulating cells to synthesise the extracellular matrix (ECM) is still a significant challenge. In this study, we investigate the use of ECM-like hydrogel materials composed of Gelatin methacryloyl (GelMA) and glycosaminoglycans (GAG), such as hyaluronic acid (HA) and chondroitin sulphate (CS), to provide a biomimetic environment for tissue repair. These hydrogels are fully characterised in terms of physico-chemical properties, including compression, swelling behaviour, rheological behaviour and via 3D printing trials. Furthermore, porous scaffolds were developed through freeze drying, producing a scaffold morphology that better promotes cell proliferation, as shown by in vitro analysis with fibroblast cells. We show that after cell seeding, freeze-dried hydrogels resulted in significantly greater amounts of DNA by day 7 compared to the GelMA hydrogel. Furthermore, freeze-dried constructs containing HA or HA/CS were found to have a significantly higher metabolic activity than GelMA alone.

Endothelial cells-derived exosomes-based hydrogel improved tendinous repair via anti-inflammatory and tissue regeneration-promoting properties

Tendon injuries are common orthopedic ailments with a challenging healing trajectory, especially in cases like the Achilles tendon afflictions. The healing trajectory of tendon injuries is often suboptimal, leading to scar formation and functional impairment due to the inherent low metabolic activity and vascularization of tendon tissue. As pressing is needed for effective interventions, efforts are made to explore biomaterials to augment tendon healing. However, tissue engineering approaches face hurdles in optimizing tissue scaffolds and nanomedical strategies. To navigate these challenges, an injectable hydrogel amalgamated with human umbilical vein endothelial cells-derived exosomes (HUVECs-Exos) was prepared and named H-Exos-gel in this study, aiming to enhance tendon repair. In our research involving a model of Achilles tendon injuries in 60 rats, we investigated the efficacy of H-Exos-gel through histological assessments performed at 2 and 4 weeks and behavioral assessments conducted at the 4-week mark revealed its ability to enhance the Achilles tendon’s mechanical strength, regulate inflammation and facilitate tendon regeneration and functional recovery. Mechanically, the H-Exos-gel modulated the cellular behaviors of macrophages and tendon-derived stem cells (TDSCs) by inhibiting inflammation-related pathways and promoting proliferation-related pathways. Our findings delineate that the H-Exos-gel epitomizes a viable bioactive medium for tendon healing, heralding a promising avenue for the clinical amelioration of tendon injuries.

Structurally diverse zinc(II) complexes containing tripodal tetradentate phenoxido-amines with promising antiproliferative effects.

Structurally diverse zinc(II) complexes with tripodal tetradentate phenolic-amines of variable substituents in the phenol and amine moieties were synthesized and thoroughly characterized. The two dinuclear [Zn2(L1)2](ClO4)2·MeOH (1), [Zn2(L2)2](ClO4)2 (2), and four mononuclear [Zn(L3)(H2O)]·MeOH (3), [Zn(L4)] (4), [Zn(L5)] (5) and [Zn(L6)] (6) complexes revealed distorted octahedral, trigonal-bipyramidal or tetrahedral geometries. The free HL1 and H2L3-6 ligands, and complexes 1-6 were evaluated for in vitro cytotoxicity against human cancer cell lines (A2780, A2780R, PC-3 and 22Rv1) and normal healthy MRC-5 cells. Overall results revealed high-to-moderate cytotoxicity (with the best IC50 values for complex 6 ranging from 2.4 to 4.5 μM), which is however, significantly higher than that of the reference drug cisplatin. The moderately active complexes 1-4 showed considerable selectivity on A2780 cells (IC50 ≈ 16.3-19.5 μM) over MRC-5 ones (with IC50 >50 μM for 1, 2 and 4, and with IC50 >25 μM for 3). The complexes 1, 2, and 6 and the ligand H2L6 were chosen for subsequent deeper biological evaluations. Their time-resolved cellular uptake and other cellular effects in A2780 cells were studied, such as cell cycle profile, intracellular ROS production, induction of apoptosis and activation of caspases 3/7. Complexes 1 and 2 caused significant G0/G1 cell cycle arrest in A2780 cells and antioxidant effects at normal conditions. They showed only limited effects on cellular processes connected with cytotoxicity, i.e. induction of apoptosis, depletion of mitochondrial membrane potential, and autophagy. These findings can be at least partly attributed to the low ability of the complexes to enter the A2780 cells and the depression of metabolic activity of the target cancer cells.

Effects of Bacillus altitudinis inoculants on cigar tobacco leaf fermentation

IntroductionMicrobial succession and metabolic adjustment during cigar tobacco leaf (CTL) fermentation are key factors to improve the quality and flavor of CTLs. However, the interactions in the above processes remain to be further elucidated.MethodsBacillus altitudinis inoculants were added to the CTLs, and metagenomics and metabolomics were used to analyze the effects of the inoculants on regulating microbial succession, metabolic shift, and aroma production during fermentation.Results and discussionThe addition of the inoculants reinforced the CTL macromolecule transformation and facilitated the aroma production efficiently, and the total aroma production was increased by 43% compared with natural fermentation. The omics analysis showed that Staphylococcus was a main contributor to fatty acid degradation, inositol phosphate metabolism, energy supply (oxidative phosphorylation), nutrient transport (ABC transporter and phosphotransferase system [PTS]), and aroma production (terpenoid backbone biosynthesis, phenylalanine metabolism, and degradation of aromatic compounds). Furthermore, Staphylococcus was positively correlated with TCA cycle intermediates (citric acid, fumaric acid, and aconitic acid), cell wall components, peptidoglycan intermediates (GlcNAc-1-P and UDP-GlcNAc), and phytic acid degradation products (inositol). The characteristics collectively showed Staphylococcus to be the most dominant in the microbial community at the genus level during microflora succession. The addition of the inoculants supplemented the nutritional components of the CTLs, enhanced the metabolic activity and diversity of bacteria such as Corynebacterium, improved their competitive advantages in the microflora succession, and facilitated the richness of microbial communities. Additionally, a metabolic shift in nicotine degradation and NAD + anabolism from Staphylococcus to Corynebacterium in fermentation with inoculants was first observed. Meanwhile, the significantly correlative differential metabolites with Staphylococcus and Corynebacterium were a metabolic complement, thus forming a completely dynamic fermentation ecosystem. The results provided evidence for CTL fermentation optimization.

Metabolic Control of Sugarcane Internode Elongation and Sucrose Accumulation

The relationship between metabolic changes occurring in the developing internodes of sugarcane and the final yield and sugar characteristics is poorly understood due to the lack of integration between phenotypic and metabolic data. To address this issue, a study was conducted where sugarcane metabolism was modeled based on the measurement of cellular components in the top internodes, at two stages of crop development. The study also looked at the effects of Trinexapac-ethyl (Moddus®) on growth inhibition. The metabolome was measured using GC-analysis, while LC-MS/MS was used to measure proteome changes in the developing internodes. These data were then integrated with the metabolic rates. Regardless of the growth rate, internode elongation was restricted to the top five internodes. In contrast, sucrose and lignin accumulation was sensitive to the growth rate. Crossover plots showed that sucrose accumulation only occurred once the cell wall synthesis had slowed down. These data suggest that sucrose accumulation controlled a reduction in sucrose breakdown for metabolic activity and a reduction in demand for carbon for cell wall polysaccharide synthesis. This study also found that nucleotide sugar metabolism appears to be a key regulator in regulating carbon flow during internode development.

Pheromone cCF10 inhibits the antibiotic persistence of Enterococcus faecalis by modulating energy metabolism

IntroductionBacterial resistance presents a major challenge to both the ecological environment and human well-being, with persistence playing a key role. Multiple studies were recently undertaken to examine the factors influencing the formation of persisters and the underlying process, with a primary focus on Gram-negative bacteria and Staphylococcus aureus (Gram-positive bacteria). Enterococcus faecalis (E. faecalis) is capable of causing a variety of infectious diseases, but there have been few studies of E. faecalis persisters. Previous studies have shown that the sex pheromone cCF10 secreted by E. faecalis induces conjugative plasmid transfer. However, whether the pheromone cCF10 regulates the persistence of E. faecalis has not been investigated.MethodsAs a result, we investigated the effect and potential molecular mechanism of pheromone cCF10 in regulating the formation of persisters in E. faecalis OG1RF using a persistent bacteria model.Results and discussionThe metabolically active E. faecalis OG1RF reached a persistence state and temporarily tolerated lethal antibiotic concentrations after 8 h of levofloxacin hydrochloride (20 mg/mL) exposure, exhibiting a persistence rate of 0.109 %. During the growth of E. faecalis OG1RF, biofilm formation was a critical factor contributing to antibiotic persistence, whereas 10 ng/mL cCF10 blocked persister cell formation. Notably, cCF10 mediated the antibiotic persistence of E. faecalis OG1RF via regulating metabolic activity rather than suppressing biofilm formation. The addition of cCF10 stimulated the Opp system and entered bacterial cells, inhibiting (p)ppGpp accumulation, thus maintaining the metabolically active state of bacteria and reducing persister cell generation. These findings offer valuable insights into the formation, as well as the control mechanism of E. faecalis persisters.

Physical, Chemical and Microbiological Changes in Mango Varieties When Cryopreserved Using Solar Energy

Fruits and vegetables are highly perishable living tissues that maintain their metabolic activity even after harvest. This study aimed to monitor the changes of physicochemical and microbiological parameters of two varieties of mango (Valencia and Camerounaise) during conservation in a photovoltaic cold room. The mangoes were stored at 10-12°C with a relative humidity of 80-90% for 3 weeks (Valencia) and 7 weeks (Camerounaise). Mango samples were taken every week for analyses. The physicochemical and microbiological parameters of mangoes were determined using standard methods. Results showed an increase in the reduced sugar content of mangoes (3.12±0.01-4.79±0.02 % for the Valencia variety and 3.01±0.08-6.22±0.02 % for the Camerounaise variety). The water content of the mango remained practically constant (85.42 % to 85.40 %) for the Valencia variety. However, an increase was observed for the Camerounaise variety (86.26±0.00-87.29±0.03 %). The titratable acidity of mangoes decreased (1.07±0.03-0.67±0.01 %) and their Brix level increased (9.8±0.01-16.20±0.01 % for the Valencia variety and 8.00±0.00-13.50±0.14 % for the Camerounaise variety). The maximum relative mass loss observed was 8.25 % for the Camerounaise variety. Regarding the microbiological analyses, the results showed a reduction in total flora and yeast and mold loads during storage. Storage in a solar cold room of fresh mangoes picked at physiological maturity and pretreated in accordance with good hygiene practices, delays the ripening process, inhibits the proliferation of surface microorganisms, preserves the physicochemical characteristics and extends the shelf life of the mangoes. Preserved mangoes are of good quality.

Type-specific inflammatory responses of vascular cells activated by interaction with virgin and aged microplastics

Microplastics (MPs) are recognized as a major environmental problem due to their ubiquitous presence in ecosystems and bioaccumulation in food chains. Not only humans are continuously exposed to these pollutants through ingestion and inhalation, but recent findings suggest they may trigger vascular inflammation and potentially worsen the clinical conditions of cardiovascular patients. Here we combine headspace analysis by needle trap microextraction-gas chromatography-mass spectrometry (HS-NTME-GC-MS) and biological assays to evaluate the effects of polystyrene, high- and low-density polyethylene MPs on phenotype, metabolic activity, and pro-inflammatory status of Vascular Smooth Muscle Cells (VSMCs) the most prominent cells in vascular walls. Virgin and artificially aged MPs (4 weeks at 40 °C and 750 W/m2 simulated solar irradiation) were comparatively tested at 1 mg/mL to simulate a realistic exposure scenario. Our results clearly show the activation of oxidative stress and inflammatory processes when VSMCs were cultured with aged polymers, with significant overexpression of IL-6 and TNF-α. In addition, volatile organic compounds (VOCs), including pentane, acrolein, propanal, and hexanal as the main components, were released by VSMCs into the headspace. Type-specific VOC response profiles were induced on vascular cells from different MPs.

Enhancing effects and mechanisms by reductive iron on constructed wetland with perfluorooctanoic acid exposure: Comparison between zero-valent and ferrous iron

Reductive iron caused efficient enhancement of constructed wetlands (CWs) under toxic stress like perfluorooctanoic acid (PFOA), while effects and mechanisms brought by different iron have not been illustrated. In this study, impacts of zero-valent (Fe(0)) and ferrous iron (Fe(II)) on CW systems with PFOA exposure were compared. Higher ammonium removal above 98 % was discovered with Fe(0) addition than Fe(II), according with more expression of hydroxylamine dehydrogenase [EC:1.7.2.6]. On the contrary, Fe(II) was more prone to stimulate activities of ammonia monooxygenase and nitrite oxidoreductase, consisting with higher abundance of Nitrosomonas and Nitrospira than Fe(0). Fe(II) had more potential to improve denitrification, with total nitrogen removal 2.64–6.83 % higher compared to Fe(0) group. It was aligned with boost of dominant denitrifying bacteria like Zoogloea (53.48 %), which probably resulted from promotion of metabolism pathways related to nitrite reduction. Phosphorus removal with Fe(II) addition was 4.59–19.04 % higher than Fe(0). Higher TP removal in Fe(II) group could result from more enhancement of physicochemical processes, compared with Fe(0). Moreover, decrease of reactive oxygen species production by citrate and activation of mitochondrial metabolism was explanation for alleviation of PFOA stress with reductive iron introduction, particularly Fe(II). As for plants, Fe(0) led to higher chlorophyll contents and lower activity of antioxidant enzymes like catalase and malondialdehyde. Current work offered new information about comparative effects of reductive iron on CWs under PFOA exposure.

Dynamic Adhesive Behavior and Biofilm Formation of Staphylococcus aureus on Polylactic Acid Surfaces in Diabetic Environments

Interest in biodegradable implants has focused attention on the resorbable polymer polylactic acid. However, the risk of these materials promoting infection, especially in patients with existing pathologies, needs to be monitored. The enrichment of a bacterial adhesion medium with compounds that are associated with human pathologies can help in understanding how these components affect the development of infectious processes. Specifically, this work evaluates the influence of glucose and ketone bodies (in a diabetic context) on the adhesion dynamics of S. aureus to the biomaterial polylactic acid, employing different approaches and discussing the results based on the physical properties of the bacterial surface and its metabolic activity. The combination of ketoacidosis and hyperglycemia (GK2) appears to be the worst scenario: this system promotes a state of continuous bacterial colonization over time, suppressing the stationary phase of adhesion and strengthening the attachment of bacteria to the surface. In addition, these supplements cause a significant increase in the metabolic activity of the bacteria. Compared to non-enriched media, biofilm formation doubles under ketoacidosis conditions, while in the planktonic state, it is glucose that triggers metabolic activity, which is practically suppressed when only ketone components are present. Both information must be complementary to understand what can happen in a real system, where planktonic bacteria are the ones that initially colonize a surface, and, subsequently, these attached bacteria end up forming a biofilm. This information highlights the need for good monitoring of diabetic patients, especially if they use an implanted device made of PLA.

Biocompatibility, bioactivity and immunomodulatory properties of three calcium silicate-based sealers: an in vitro study on hPDLSCs

ObjectivesTo assess the biocompatibility, bioactivity, and immunomodulatory properties of three new calcium silicate cement-based sealers: Ceraseal (CS), Totalfill BC Sealer (TFbc) and WellRoot ST (WR-ST) on human periodontal ligament stem cells (hPDLSCs).Materials and methodsHPDLSCs were isolated from extracted third molars from healthy patients. Eluates (1:1, 1:2, and 1:4 ratio) and sample discs of CS, TFbc and WR-ST after setting were prepared. A series of assays were performed: cell characterization, cell metabolic activity (MTT assay) cell attachment and morphology (SEM assay), cell migration (wound-healing assay), cytoskeleton organization (phaloidin-based assay); IL-6 and IL-8 release (ELISA); differentiation marker expression (RT-qPCR assay), and cell mineralization (Alizarin Red S staining). HPDLSCs cultured in unconditioned (negative control) or osteogenic (positive control) culture media were used as a comparison. Statistical significance was established at p < 0.05.ResultsAll the tested sealers exhibited similar results in the cytocompatibility assays (cell metabolic activity, migration, attachment, morphology, and cytoskeleton organization) compared with a negative control group. CS and TFbc exhibited an upregulation of at least one osteo/cementogenic marker compared to the negative and positive control groups. CS and TFbc also showed a significantly higher calcified nodule formation than the negative and positive control groups. Both the marker expression and calcified nodule formation were significantly higher in CS-treated cells than TFbc treated cells. WR-ST exhibited similar results to the control group. CS and TFbc-treated cells exhibited a significant downregulation of IL-6 after 72 h of culture compared to the negative control group (p < 0.05).ConclusionAll the tested sealers exhibited an adequate cytocompatibility. CS significantly enhances cell differentiation by upregulating the expression of key genes associated with bone and cementum formation. Additionally, CS was observed to facilitate the mineralization of the extracellular matrix effectively. In contrast, the effects of TFbc and WR-ST on these processes were less pronounced compared to CS. Furthermore, both CS and TFbc exhibited an anti-inflammatory potential, contributing to their potential therapeutic benefits in regenerative endodontics.Clinical relevanceThis is the first study to compare the biological properties and immunomodulatory potential of Ceraseal, Totalfill BC Sealer, and WellRoot ST. The results act as supporting evidence for their use in root canal treatment.