The natural antimicrobial properties of essential oils (EOs) have contributed to the battle against multidrug-resistant microorganisms by providing new ways to develop more effective antibiotic agents. In this study, we investigated the chemical composition of Ocotea diospyrifolia essential oil (OdOE) and its antimicrobial properties combined with amikacin (AMK). Through gas chromatography-mass spectrometry (GCMS) analysis, the primary constituents of OdOE were identified as α-bisabolol (45.8%), β-bisabolene (9.4%), γ-elemene (7.6%), (Z)- β-farnesene (5.2%), spathulenol (3.5%), (Z)-caryophyllene (3.3%), and (E)-caryophyllene (3.1%). In vitro assessments showed that the combined administration of OdOE and AMK exerted a synergistic antibacterial effect on the multidrug-resistant K. pneumoniae strain. This synergistic effect demonstrated bacteriostatic action. OdEO combined with amikacin showed protein extravasation within 2 h of treatment, leading to bacterial death, which was determined by a reduction in viable cell count. The effective concentrations showed hemocompatibility. In vivo assessments using Caenorhabditis elegans as a model showed the survival of 85% of infected nematodes. Therefore, the combination OdEO combined with amikacin exhibited antimicrobial activity against a multidrug-resistant K. pneumoniae strain. Thus, OdOE is a promising agent that may be considered for development of antimicrobial treatment.

6-Cyanodopamine is a novel catecholamine released from rabbit isolated heart. However, it is not known whether this catecholamine presents any biological activity. Here, it was evaluated whether 6-cyanodopamine (6-CYD) is released from rat vas deferens and its effect on this tissue contractility. Basal release of 6-CYD, 6-nitrodopamine (6-ND), 6-bromodopamine, 6-nitrodopa, and 6-nitroadrenaline from vas deferens were quantified by LC-MS/MS. Electric-field stimulation (EFS) and concentration-response curves to noradrenaline, adrenaline, and dopamine of the rat isolated epididymal vas deferens (RIEVD) were performed in the absence and presence of 6-CYD and /or 6-ND. Expression of tyrosine hydroxylase was assessed by immunohistochemistry. The rat isolated vas deferens released significant amounts of both 6-CYD and 6-ND. The voltage-gated sodium channel blocker tetrodotoxin had no effect on the release of 6-CYD, but it virtually abolished 6-ND release. 6-CYD alone exhibited a negligible RIEVD contractile activity; however, at 10 nM, 6-CYD significantly potentiated the noradrenaline- and EFS-induced RIEVD contractions, whereas at 10 and 100 nM, it also significantly potentiated the adrenaline- and dopamine-induced contractions. The potentiation of noradrenaline- and adrenaline-induced contractions by 6-CYD was unaffected by tetrodotoxin. Co-incubation of 6-CYD (100 pM) with 6-ND (10 pM) caused a significant leftward shift and increased the maximal contractile responses to noradrenaline, even in the presence of tetrodotoxin. Immunohistochemistry revealed the presence of tyrosine hydroxylase in both epithelial cell cytoplasm of the mucosae and nerve fibers of RIEVD. The identification of epithelium-derived 6-CYD and its remarkable synergism with catecholamines indicate that epithelial cells may regulate vas deferens smooth muscle contractility.

UNASSIGNED: Despite the availability of chemotherapy drugs such as 5-fluorouracil (5-FU), the treatment of some cancers such as gastric cancer remains challenging due to drug resistance and side effects. This study aimed to investigate the effect of celastrol in combination with the chemotherapy drug 5-FU on proliferation and induction of apoptosis in human gastric cancer cell lines (AGS and EPG85-257).
UNASSIGNED: In this in vitro study, AGS and EPG85-257 cells were treated with different concentrations of celastrol, 5-FU, and their combination. Cell proliferation was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The synergistic effect of 5-FU and celastrol was studied using Compusyn software. The DNA content at different phases of the cell cycle and apoptosis rate was measured using flow cytometry.
UNASSIGNED: Co-treatment with low concentrations (10% inhibitory concentration (IC10)) of celastrol and 5-FU significantly reduced IC50 (p < 0.05) so that 48 h after treatment, IC50 was calculated at 3.77 and 6.9 μM for celastrol, 20.7 and 11.6 μM for 5-FU, and 5.03 and 4.57 μM for their combination for AGS and EPG85-257 cells, respectively. The mean percentage of apoptosis for AGS cells treated with celastrol, 5-FU, and their combination was obtained 23.9, 41.2, and 61.9, and for EPG85-257 cells 5.65, 46.9, and 55.7, respectively. In addition, the 5-FU and celastrol-5-FU combination induced cell cycle arrest in the synthesis phase.
UNASSIGNED: Although celastrol could decrease the concentration of 5-fluorouracil that sufficed to suppress gastric cancer cells, additional studies are required to arrive at conclusive evidence on the anticancer effects of celastrol.

In feed, propionic acid is the weak organic acid of choice to prevent growth of spoilage fungi. For safe and easy industrial handling this antifungal agent is applied in the presence of neutralizing ammonium, which however has the disadvantage to negatively affect the efficacy of fungus-inhibiting properties of the formulation. In the present study we investigated the impact of medium chain fatty acids (MCFA) on the antifungal efficacy of an ammonium propionate formulation on dormant- and germinating conidia as well as germ tubes and hyphae of Aspergillus chevalieri, a xerophilic fungus predominant on moulded feed. Dormant conidia were not affected by 32 mM of ammonium propionate after a 28 h-treatment in demi water. Similar results were obtained with solely 0.52 mM MCFA. However, the combination of both components nearly eradicated formation of colonies from these conidia and was accompanied by distortion of the cellular structure as was visible with light- and transmission electron microscopy. Germination of conidia, characterised by swelling and germ tube formation, was significantly decreased in the presence of 16 mM ammonium propionate and 0.26 mM MCFA, while the latter component itself did not significantly decrease germination. We conclude that a combination of ammonium propionate and MCFA had a synergistic antifungal effect on dormant and germinating conidia. When the combination of ammonium propionate and MCFA was tested on hyphae for 30 min, we observed that cell death was significantly increased in comparison to components alone. Treatment of the hyphae with 16 mM of ammonium propionate caused aberrant mitochondria, as evidenced by irregularly shaped and enlarged mitochondria that contained electron-dense inclusions as observed by transmission electron microscopy. When the combination of ammonium propionate and MCFA was applied against the hyphae, more severe cell damage was observed, with signs of autophagy. Summarised, our results demonstrate synergistic antifungal effects of ammonium propionate and medium chain fatty acids on fungal survival structures, during their germination and after a short (sudden) treatment of growing cells. This is of potential importance for several areas of feed and food storage and shelf-life.

Due to limited effective therapeutics for uterine leiomyosarcoma (uLMS), the impact of the gamma secretase inhibitor (GSI) MK-0752 with common chemotherapeutics was explored in uLMS. MTT assays were performed on two human uLMS cell lines, SK-UT-1B and SK-LMS-1, using MK-0752, docetaxel, doxorubicin, and gemcitabine, individually and in combination, to determine cell viability after treatment. Synergistic combinations were used in transwell invasion assays, cell cycle flow cytometry, proliferation assays, and RNA sequencing. In SK-UT-1B, MK-0752 was synergistic with doxorubicin and gemcitabine plus docetaxel. In SK-LMS-1, MK-0752 was synergistic with all individual agents and with the combination of gemcitabine plus docetaxel. MK-0752, gemcitabine, and docetaxel decreased invasion in SK-UT-1B 2.1-fold* and in SK-LMS-1 1.7-fold*. In SK-LMS-1, invasion decreased 1.2-fold* after treatment with MK-0752 and docetaxel and 2.2-fold* after treatment with MK-0752 and doxorubicin. Cell cycle analysis demonstrated increases in the apoptotic sub-G1 population with MK-0752 alone in SK-UT-1B (1.4-fold*) and SK-LMS-1 (2.7-fold**), along with increases with all combinations in both cell lines. The combination treatments had limited effects on proliferation, while MK-0752 alone decreased proliferation in SK-LMS-1 (0.63-fold**). Both MK-0752 alone and in combination altered gene expression and KEGG pathways. In conclusion, the combinations of MK-0752 with either doxorubicin, docetaxel, or gemcitabine plus docetaxel are potential novel therapeutic approaches for uLMS. (* p < 0.05, ** p < 0.01).

Pesticides are often detected in freshwater, but their impact on the aquatic environment is commonly studied based on single compounds, underestimating the potential additive effects of these mixtures. Even at low concentrations, pesticides can negatively affect organisms, altering important behaviors that can have repercussions at the population level. This study used a multi-behavioral approach to evaluate the effects of zebrafish larvae exposure to carbendazim (C), fipronil (F), and sulfentrazone (S), individually and mixed. Five behavioral tests, thigmotaxis, touch sensitivity, optomotor response, bouncing ball test, and larval exploratory behavior, were performed to assess potential effects on anxiety, fear, and spatial and social interaction. Significant changes were observed in the performance of larvae exposed to all compounds and their mixtures. Among the single pesticides, exposure to S produced the most behavioral alterations, followed by F and C, respectively. A synergistic effect between the compounds was observed in the C + F group, which showed more behavioral effects than the groups exposed to pesticides individually. The use of behavioral tests to evaluate pesticide mixtures is important to standardize methods and associate behavioral changes with ecologically relevant events, thus creating a more realistic scenario for investigating the potential environmental impacts of these compounds.

With the increasing burden of carbapenem-resistant Klebsiella pneumoniae (CR-Kp), including high rates of healthcare-associated infections, treatment failure, and mortality, a good therapeutic strategy for attacking this multi-resistant pathogen is one of the main goals in current medical practice and necessitates the use of novel antibiotics or new drug combinations.
OBJECTIVE: We reviewed the clinical and microbiological outcomes of seven patients treated at the \"Agrippa Ionescu\" Clinical Emergency Hospital between October 2023 and January 2024, aiming to demonstrate the synergistic activity of the ceftazidime-avibactam (C/A) plus aztreonam (ATM) combination against the co-producers of blaNDM + blaOXA-48-like CR-Kp.
METHODS: Seven CR-Kp with blaNDM and blaOXA-48 as resistance mechanisms were tested. Seven patients treated with C/A + ATM were included. The synergistic activity of C/A + ATM was proven through double-disk diffusion in all seven isolates. Resistance mechanisms like KPC, VIM, OXA-48, NDM, IMP, and CTX-M were assessed through immunochromatography.
RESULTS: With a mean of nine days of treatment with the synergistic combination C/A + ATM, all patients achieved clinical recovery, and five achieved microbiological recovery.
CONCLUSIONS: With the emerging co-occurrence of blaOXA-48 and blaNDM among Kp in Romania, the combination of C/A and ATM could be a promising therapeutic option.

Infections caused by KPC-producing K. pneumoniae continue to pose a significant clinical challenge due to their emerging resistance to new antimicrobials. We investigated the association between two drugs whose roles have been repurposed against multidrug-resistant bacteria: fosfomycin and temocillin. Temocillin exhibits unusual stability against KPC enzymes, while fosfomycin acts as a potent \"synergizer\". We conducted in vitro antimicrobial activity studies on 100 clinical isolates of KPC-producing K. pneumoniae using a combination of fosfomycin and temocillin. The results demonstrated synergistic activity in 91% of the isolates. Subsequently, we assessed the effect on Galleria mellonella larvae using five genetically different KPC-Kp isolates. The addition of fosfomycin to temocillin increased larvae survival from 73 to 97% (+Δ 32%; isolate 1), from 93 to 100% (+Δ 7%; isolate 2), from 63 to 86% (+Δ 36%; isolate 3), from 63 to 90% (+Δ 42%; isolate 4), and from 93 to 97% (+Δ 4%; isolate 10). Among the temocillin-resistant KPC-producing K. pneumoniae isolates (24 isolates), the addition of fosfomycin reduced temocillin MIC values below the resistance breakpoint in all isolates except one. Temocillin combined with fosfomycin emerges as a promising combination against KPC-producing K. pneumoniae, warranting further clinical evaluation.

Understanding the interactions among anthropogenic stressors is critical for effective conservation and management of ecosystems. Freshwater scientists have invested considerable resources in conducting factorial experiments to disentangle stressor interactions by testing their individual and combined effects. However, the diversity of stressors and systems studied has hindered previous syntheses of this body of research. To overcome this challenge, we used a novel machine learning framework to identify relevant studies from over 235,000 publications. Our synthesis resulted in a new dataset of 2396 multiple-stressor experiments in freshwater systems. By summarizing the methods used in these studies, quantifying trends in the popularity of the investigated stressors, and performing co-occurrence analysis, we produce the most comprehensive overview of this diverse field of research to date. We provide both a taxonomy grouping the 909 investigated stressors into 31 classes and an open-source and interactive version of the dataset (https://jamesaorr.shinyapps.io/freshwater-multiple-stressors/). Inspired by our results, we provide a framework to help clarify whether statistical interactions detected by factorial experiments align with stressor interactions of interest, and we outline general guidelines for the design of multiple-stressor experiments relevant to any system. We conclude by highlighting the research directions required to better understand freshwater ecosystems facing multiple stressors.

Cytotoxins (CTs) are three-finger membrane-active toxins present mainly in cobra venom. Our analysis of the available CT amino acid sequences, literature data on their membrane activity, and conformational equilibria in aqueous solution and detergent micelles allowed us to identify specific amino acid residues which interfere with CT incorporation into membranes. They include Pro9, Ser28, and Asn/Asp45 within the N-terminal, central, and C-terminal loops, respectively. There is a hierarchy in the effect of these residues on membrane activity: Pro9 > Ser28 > Asn/Asp45. Taking into account all the possible combinations of special residues, we propose to divide CTs into eight groups. Group 1 includes toxins containing all of the above residues. Their representatives demonstrated the lowest membrane activity. Group 8 combines CTs that lack these residues. For the toxins from this group, the greatest membrane activity was observed. We predict that when solely membrane activity determines the cytotoxic effects, the activity of CTs from a group with a higher number should exceed that of CTs from a group with a lower number. This classification is supported by the available data on the cytotoxicity and membranotropic properties of CTs. We hypothesize that the special amino acid residues within the loops of the CT molecule may indicate their involvement in the interaction with non-lipid targets.