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1.
BMC Microbiol ; 24(1): 60, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38373929

RESUMEN

BACKGROUND: The impact of probiotic strains on host health is widely known. The available studies on the interaction between bacteria and the host are focused on the changes induced by bacteria in the host mainly. The studies determining the changes that occurred in the bacteria cells are in the minority. Within this paper, we determined what happens to the selected Bifidobacterium adolescentis and Bifidobacterium longum ssp. longum in an experimental environment with the intestinal epithelial layer. For this purpose, we tested the bacteria cells' viability, redox activity, membrane potential and enzymatic activity in different environments, including CaCo-2/HT-29 co-culture, cell culture medium, presence of inflammatory inductor (TNF-α) and oxygen. RESULTS: We indicated that the external milieu impacts the viability and vitality of bacteria. Bifidobacterium adolescentis decrease the size of the live population in the cell culture medium with and without TNF-α (p < 0.001 and p < 0.01 respectively). In contrast, Bifidobacterium longum ssp. longum significantly increased survivability in contact with the eukaryotic cells and cell culture medium (p < 0.001). Bifidobacterium adolescentis showed significant changes in membrane potential, which was decreased in the presence of eukaryotic cells (p < 0.01), eukaryotic cells in an inflammatory state (p < 0.01), cell culture medium (p < 0.01) and cell culture medium with TNF-α (p < 0.05). In contrast, Bifidobacterium longum ssp. longum did not modulate membrane potential. Instead, bacteria significantly decreased the redox activity in response to milieus such as eukaryotic cells presence, inflamed eukaryotic cells as well as the culture medium (p < 0.001). The redox activity was significantly different in the cells culture medium vs the presence of eukaryotic cells (p < 0.001). The ability to ß-galactosidase production was different for selected strains: Bifidobacterium longum ssp. longum indicated 91.5% of positive cells, whereas Bifidobacterium adolescentis 4.34% only. Both strains significantly reduced the enzyme production in contact with the eukaryotic milieu but not in the cell culture media. CONCLUSION: The environmental-induced changes may shape the probiotic properties of bacterial strains. It seems that the knowledge of the sensitivity of bacteria to the external environment may help to select the most promising probiotic strains, reduce research costs, and contribute to greater reproducibility of the obtained probiotic effects.


Asunto(s)
Bifidobacterium adolescentis , Bifidobacterium longum , Bifidobacterium , Probióticos , Humanos , Factor de Necrosis Tumoral alfa , Células CACO-2 , Células Eucariotas , Reproducibilidad de los Resultados , Bacterias
2.
Front Zool ; 21(1): 14, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38807222

RESUMEN

The investigation of the effects of artificial 50 Hz electric field (E-field) frequency on Apis mellifera is a relatively new field of research. Since the current literature focuses mainly on short-term effects, it is unknown whether E-fields have permanent effects on bees or whether their effects can be neutralized. In this study we assessed gene expression immediately after exposure to the E-field, as well as 7 days after exposure. The aim of this work was to identify potentially dysregulated gene transcripts in honey bees that correlate with exposure time and duration to E-fields.Newly emerged bees were marked daily with a permanent marker (one color for each group). Then bees were exposed to the 50 Hz E-field with an intensity of 5.0 kV/m or 10.0 kV/m for 1-3 h. After exposure, half of the bees were analyzed for gene expression changes. The other half were transferred to a colony kept in a mini-hive. After 7 days, marked bees were collected from the mini-hive for further analysis. Six regulated transcripts were selected of transcripts involved in oxidative phosphorylation (COX5a) and transcripts involved in endocrine functions (HBG-3, ILP-1), mitochondrial inner membrane transport (TIM10), and aging (mRPL18, mRPS30).Our study showed that in Apis mellifera the expression of selected genes is altered in different ways after exposure to 50 Hz electric fields -. Most of those expression changes in Cox5a, mRPL18, mRPS30, and HGB3, were measurable 7 days after a 1-3 h exposure. These results indicate that some E-field effects may be long-term effects on honey bees due to E-field exposure, and they can be observed 7 days after exposure.

3.
J Nanobiotechnology ; 22(1): 183, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38622691

RESUMEN

BACKGROUND: The use of cells as carriers for the delivery of nanoparticles is a promising approach in anticancer therapy, mainly due to their natural properties, such as biocompatibility and non-immunogenicity. Cellular carriers prevent the rapid degradation of nanoparticles, improve their distribution, reduce cytotoxicity and ensure selective delivery to the tumor microenvironment. Therefore, we propose the use of phagocytic cells as boron carbide nanoparticle carriers for boron delivery to the tumor microenvironment in boron neutron capture therapy. RESULTS: Macrophages originating from cell lines and bone marrow showed a greater ability to interact with boron carbide (B4C) than dendritic cells, especially the preparation containing larger nanoparticles (B4C 2). Consequently, B4C 2 caused greater toxicity and induced the secretion of pro-inflammatory cytokines by these cells. However, migration assays demonstrated that macrophages loaded with B4C 1 migrated more efficiently than with B4C 2. Therefore, smaller nanoparticles (B4C 1) with lower toxicity but similar ability to activate macrophages proved to be more attractive. CONCLUSIONS: Macrophages could be promising cellular carriers for boron carbide nanoparticle delivery, especially B4C 1 to the tumor microenvironment and thus prospective use in boron neutron capture therapy.


Asunto(s)
Terapia por Captura de Neutrón de Boro , Nanopartículas , Boro , Línea Celular Tumoral , Nanopartículas/metabolismo , Macrófagos
4.
Int J Mol Sci ; 24(6)2023 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-36982505

RESUMEN

Amyloid ß peptides (Aß) aggregating in the brain have a potential neurotoxic effect and are believed to be a major cause of Alzheimer's disease (AD) development. Thus, inhibiting amyloid polypeptide aggregation seems to be a promising approach to the therapy and prevention of this neurodegenerative disease. The research presented here is directed at the determination of the inhibitory activity of ovocystatin, the cysteine protease inhibitor isolated from egg white, on Aß42 fibril genesis in vitro. Thioflavin-T (ThT) assays, which determine the degree of aggregation of amyloid peptides based on fluorescence measurement, circular dichroism spectroscopy (CD), and transmission electron microscopy (TEM) have been used to assess the inhibition of amyloid fibril formation by ovocystatin. Amyloid beta 42 oligomer toxicity was measured using the MTT test. The results have shown that ovocystatin possesses Aß42 anti-aggregation activity and inhibits Aß42 oligomer toxicity in PC12 cells. The results of this work may help in the development of potential substances able to prevent or delay the process of beta-amyloid aggregation-one of the main reasons for Alzheimer's disease.


Asunto(s)
Enfermedad de Alzheimer , Enfermedades Neurodegenerativas , Ratas , Animales , Humanos , Péptidos beta-Amiloides/química , Enfermedad de Alzheimer/tratamiento farmacológico , Fragmentos de Péptidos/farmacología , Amiloide/química
5.
Int J Mol Sci ; 23(10)2022 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-35628607

RESUMEN

Bacterial extracellular vesicles (EVs) perform various biological functions, including those that are critical to microbes. Determination of EVs composition allows for a deep understanding of their role in the bacterial community and communication among them. Cutibacterium acnes, formerly Propionibacteriumacnes, are commensal bacteria responsible for various infections, e.g., prosthesis, sarcoidosis, soft-tissue infections, and the most known but still controversial-acnes lesion. In C. acnes, three major phylotypes represented variable disease associations. Herein, for the first time, we present a comparative analysis of EVs obtained from three C. acnes phylotypes (IA1, IB, and II) to demonstrate the existence of differences in their protein and lipid composition. In the following work, the morphological analysis of EVs was performed, and the SDS-PAGE protein profile and the lipid profile were presented using the TLC and MALDI-TOF MS methods. This study allowed us to show major differences between the protein and lipid composition of C. acnes EVs. This is a clear indication that EVs released by different phylotypes of the one species are not identical to each other in terms of composition and should be separately analyzed each time to obtain reliable results.


Asunto(s)
Acné Vulgar , Vesículas Extracelulares , Infecciones por Bacterias Grampositivas , Acné Vulgar/microbiología , Infecciones por Bacterias Grampositivas/microbiología , Humanos , Lípidos , Propionibacterium acnes
6.
Int J Mol Sci ; 23(10)2022 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-35628352

RESUMEN

Despite many attempts, trials, and treatment procedures, pancreatic ductal adenocarcinoma (PDAC) still ranks among the most deadly and treatment-resistant types of cancer. Hence, there is still an urgent need to develop new molecules, drugs, and therapeutic methods against PDAC. Naturally derived compounds, such as pentacyclic terpenoids, have gained attention because of their high cytotoxic activity toward pancreatic cancer cells. Ursolic acid (UA), as an example, possesses a wide anticancer activity spectrum and can potentially be a good candidate for anti-PDAC therapy. However, due to its minimal water solubility, it is necessary to prepare an optimal nano-sized vehicle to overcome the low bioavailability issue. Poly(lactic-co-glycolic acid) (PLGA) polymeric nanocarriers seem to be an essential tool for ursolic acid delivery and can overcome the lack of biological activity observed after being incorporated within liposomes. PLGA modification, with the addition of PEGylated phospholipids forming the lipid shell around the polymeric core, can provide additional beneficial properties to the designed nanocarrier. We prepared UA-loaded hybrid PLGA/lipid nanoparticles using a nanoprecipitation method and subsequently performed an MTT cytotoxicity assay for AsPC-1 and BxPC-3 cells and determined the hemolytic effect on human erythrocytes with transmission electron microscopic (TEM) visualization of the nanoparticles and their cellular uptake. Hybrid UA-loaded lipid nanoparticles were also examined in terms of their stability, coating dynamics, and ursolic acid loading. We established innovative and repeatable preparation procedures for novel hybrid nanoparticles and obtained biologically active nanocarriers for ursolic acid with an IC50 below 20 µM, with an appropriate size for intravenous dosage (around 150 nm), high homogeneity of the sample (below 0.2), satisfactory encapsulation efficiency (up to 70%) and excellent stability. The new type of hybrid UA-PLGA nanoparticles represents a further step in the development of potentially effective PDAC therapies based on novel, biologically active, and promising triterpenoids.


Asunto(s)
Adenocarcinoma , Nanopartículas , Neoplasias Pancreáticas , Triterpenos , Humanos , Ácido Láctico , Liposomas , Neoplasias Pancreáticas/tratamiento farmacológico , Tamaño de la Partícula , Ácido Poliglicólico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Triterpenos/farmacología , Ácido Ursólico
7.
Int J Mol Sci ; 23(21)2022 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-36362310

RESUMEN

Staphylococcal biofilms are major causative factors of non-healing wound infections. Their treatment algorithms recommend the use of locally applied antiseptic agents to counteract the spread of infection. The efficacy of antiseptics against biofilm is assessed in vitro by a set of standard quantitative and semi-quantitative methods. The development of software for image processing additionally allowed for the obtainment of quantitative data from microscopic images of biofilm dyed with propidium iodine and SYTO-9 reagents, differentiating dead cells from live ones. In this work, the method of assessment of the impact of antiseptic agents on staphylococcal biofilm in vitro, based on biofilms' processed images, was proposed and scrutinized with regard to clinically relevant antiseptics, polyhexanide, povidone-iodine and hypochlorite. The standard quantitative culturing method was applied to validate the obtained data from processed images. The results indicated significantly higher activity of polyhexanide and povidone-iodine than hypochlorite against staphylococcal biofilm. Taking into account the fact that in vitro results of the efficacy of antiseptic agents against staphylococcal biofilm are frequently applied to back up their use in hospitals and ambulatory units, our work should be considered an important tool; providing reliable, quantitative data in this regard.


Asunto(s)
Antiinfecciosos Locales , Infecciones Estafilocócicas , Humanos , Staphylococcus aureus , Povidona Yodada/farmacología , Ácido Hipocloroso , Antiinfecciosos Locales/farmacología , Biopelículas , Infecciones Estafilocócicas/tratamiento farmacológico , Antibacterianos/uso terapéutico
8.
Int J Mol Sci ; 22(5)2021 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-33800082

RESUMEN

Helicobacter pylori, a gastric pathogen associated with a broad range of stomach diseases, has a high tendency to become resistant to antibiotics. One of the most important factors related to therapeutic failures is its ability to change from a spiral to a coccoid form. Therefore, the main aim of our original article was to determine the influence of myricetin, a natural compound with an antivirulence action, on the morphological transformation of H. pylori and check the potential of myricetin to increase the activity of antibiotics against this pathogen. We observed that sub-minimal inhibitory concentrations (sub-MICs) of this compound have the ability to slow down the process of transformation into coccoid forms and reduce biofilm formation of this bacterium. Using checkerboard assays, we noticed that the exposure of H. pylori to sub-MICs of myricetin enabled a 4-16-fold reduction in MICs of all classically used antibiotics (amoxicillin, clarithromycin, tetracycline, metronidazole, and levofloxacin). Additionally, RT-qPCR studies of genes related to the H. pylori morphogenesis showed a decrease in their expression during exposure to myricetin. This inhibitory effect was more strongly seen for genes involved in the muropeptide monomers shortening (csd3, csd6, csd4, and amiA), suggesting their significant participation in the spiral-to-coccoid transition. To our knowledge, this is the first research showing the ability of any compound to synergistically interact with all five antibiotics against H. pylori and the first one showing the capacity of a natural substance to interfere with the morphological transition of H. pylori from spiral to coccoid forms.


Asunto(s)
Antibacterianos/farmacología , Flavonoides/farmacología , Helicobacter pylori/efectos de los fármacos , Biopelículas/efectos de los fármacos , Sinergismo Farmacológico , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Helicobacter pylori/patogenicidad , Helicobacter pylori/fisiología , Pruebas de Sensibilidad Microbiana
9.
Int J Mol Sci ; 22(11)2021 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-34072418

RESUMEN

Staphylococcus aureus is one of the most prevalent pathogens associated with several types of biofilm-based infections, including infections of chronic wounds. Mature staphylococcal biofilm is extremely hard to eradicate from a wound and displays a high tendency to induce recurring infections. Therefore, in the present study, we aimed to investigate in vitro the interaction between S. aureus biofilm and fibroblast cells searching for metabolites that could be considered as potential biomarkers of critical colonization and infection. Utilizing advanced microscopy and microbiological methods to examine biofilm formation and the staphylococcal infection process, we were able to distinguish 4 phases of biofilm development. The analysis of staphylococcal biofilm influence on the viability of fibroblasts allowed us to pinpoint the moment of critical colonization-12 h post contamination. Based on the obtained model we performed a metabolomics analysis by 1H NMR spectroscopy to provide new insights into the pathophysiology of infection. We identified a set of metabolites related to the switch to anaerobic metabolism that was characteristic for staphylococcal biofilm co-cultured with fibroblast cells. The data presented in this study may be thus considered a noteworthy but preliminary step in the direction of developing a new, NMR-based tool for rapid diagnosing of infection in a chronic wound.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Técnicas de Cocultivo , Fibroblastos/metabolismo , Fibroblastos/microbiología , Staphylococcus aureus/crecimiento & desarrollo , Staphylococcus aureus/metabolismo , Supervivencia Celular , Fibroblastos/ultraestructura , Técnica del Anticuerpo Fluorescente , Interacciones Huésped-Patógeno , Cinética , Espectroscopía de Resonancia Magnética , Metaboloma , Metabolómica/métodos , Staphylococcus aureus/ultraestructura
10.
Int J Mol Sci ; 22(22)2021 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-34830278

RESUMEN

Methicillin-resistant strains of Staphylococcus aureus (MRSA) have developed resistance to most ß-lactam antibiotics and have become a global health issue. In this work, we analyzed the impact of a rotating magnetic field (RMF) of well-defined and strictly controlled characteristics coupled with ß-lactam antibiotics against a total of 28 methicillin-resistant and sensitive S. aureus strains. The results indicate that the application of RMF combined with ß-lactam antibiotics correlated with favorable changes in growth inhibition zones or in minimal inhibitory concentrations of the antibiotics compared to controls unexposed to RMF. Fluorescence microscopy indicated a drop in the relative number of cells with intact cell walls after exposure to RMF. These findings were additionally supported by the use of SEM and TEM microscopy, which revealed morphological alterations of RMF-exposed cells manifested by change of shape, drop in cell wall density and cytoplasm condensation. The obtained results indicate that the originally limited impact of ß-lactam antibiotics in MRSA is boosted by the disturbances caused by RMF in the bacterial cell walls. Taking into account the high clinical need for new therapeutic options, effective against MRSA, the data presented in this study have high developmental potential and could serve as a basis for new treatment options for MRSA infections.


Asunto(s)
Antibacterianos/farmacología , Campos Magnéticos , Resistencia a la Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , beta-Lactamas/farmacología , Pared Celular/efectos de los fármacos , Terapia Combinada/métodos , Pruebas de Sensibilidad Microbiana
11.
Int J Mol Sci ; 22(19)2021 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-34639147

RESUMEN

In this work, we verified the possibility of valorizing a major waste product of the potato starch industry, potato tuber juice (PJ). We obtained a cost-effective, ecological-friendly microbiological medium that yielded bacterial cellulose (BC) with properties equivalent to those from conventional commercial Hestrin-Schramm medium. The BC yield from the PJ medium (>4 g/L) was comparable, despite the lack of any pre-treatment. Likewise, the macro- and microstructure, physicochemical parameters, and chemical composition showed no significant differences between PJ and control BC. Importantly, the BC obtained from PJ was not cytotoxic against fibroblast cell line L929 in vitro and did not contain any hard-to-remove impurities. The PJ-BC soaked with antiseptic exerted a similar antimicrobial effect against Staphylococcus aureus and Pseudomonas aeruginosa as to BC obtained in the conventional medium and supplemented with antiseptic. These are very important aspects from an application standpoint, particularly in biomedicine. Therefore, we conclude that using PJ for BC biosynthesis is a path toward significant valorization of an environmentally problematic waste product of the starch industry, but also toward a significant drop in BC production costs, enabling wider application of this biopolymer in biomedicine.


Asunto(s)
Bacterias/metabolismo , Celulosa/biosíntesis , Análisis Costo-Beneficio , Fibroblastos/metabolismo , Residuos Industriales/economía , Solanum tuberosum/química , Animales , Celulosa/economía , Medios de Cultivo , Jugos de Frutas y Vegetales/análisis , Ratones , Almidón/química
12.
BMC Cancer ; 20(1): 481, 2020 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-32460717

RESUMEN

BACKGROUND: High-intensity ultrasound (HIUS) has been increasingly investigated as a possible tool in the treatment of multiple tumor entities. However, there is only little knowledge on the effect of HIUS on the peritoneum. This preliminary study aims to investigate HIUS' potential for altering the peritoneal surface and potentially improving current treatments for peritoneal metastases. For this purpose, HIUS' qualitative and quantitative structural effects on the peritoneal tissue were analyzed by means of light, fluorescence and electron microscopy. METHODS: Proportional sections were cut from the fresh postmortem swine peritoneum. Peritoneal surfaces were covered with a 6 mm thick liquid film of 0.9% NaCl. HIUS was applied in all tissue samples for 0 (control), 30, 60, 120 and 300 s. Peritoneal tissues were analyzed using light-, fluorescence and electron microscopy to detect possible structural changes within the tissues. RESULTS: Following HIUS, a superficial disruption of peritoneal tissue was visible in light microscopy, which amplified with increased time of HIUS' application. Fluorescence microscopy showed both peritoneal and subperitoneal disruption with tissue gaps. Electron microscopy revealed structural filamentation of the peritoneal surface. CONCLUSION: Our data indicate that HIUS causes a wide range of effects on the peritoneal tissue, including the formation of small ruptures in both peritoneal and subperitoneal tissues. However, according to our findings, these disruptions are limited to a microscopical level. Further studies are required to evaluate whether HIUS application can benefit current therapeutic regimens on peritoneal metastases and possibly enhance the efficacy of intraperitoneal chemotherapy.


Asunto(s)
Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Peritoneo , Animales , Microscopía , Microscopía Electrónica , Microscopía Fluorescente , Peritoneo/lesiones , Cloruro de Sodio , Sonicación/métodos , Sus scrofa , Factores de Tiempo
13.
Int J Mol Sci ; 21(24)2020 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-33327555

RESUMEN

Helicobacter pylori is a bacterium known mainly of its ability to cause persistent inflammations of the human stomach, resulting in peptic ulcer diseases and gastric cancers. Continuous exposure of this bacterium to antibiotics has resulted in high detection of multidrug-resistant strains and difficulties in obtaining a therapeutic effect. The purpose of the present study was to determine the usability of bacterial cellulose (BC) chemisorbed with 3-bromopyruvate (3-BP) or sertraline (SER) to act against lawn H. pylori biofilms. The characterization of BC carriers was made using a N2 adsorption/desorption analysis, tensile strength test, and scanning electron microscopy (SEM) observations. Determination of an antimicrobial activity was performed using a modified disk-diffusion method and a self-designed method of testing antibacterial activity against biofilm microbial forms. In addition, bacterial morphology was checked by SEM. It was found that BC disks were characterized by a high cross-linking and shear/stretch resistance. Growth inhibition zones for BC disks chemisorbed with 2 mg of SER or 3-BP were equal to 26.5-27.5 mm and 27-30 mm, respectively. The viability of lawn biofilm H. pylori cells after a 4-h incubation with 2 mg SER or 3-BP chemisorbed on BC disks was ≥4 log lower, suggesting their antibacterial effect. SEM observations showed a number of morphostructural changes in H. pylori cells exposed to these substances. Concluding, SER and 3-BP chemisorbed on BC carriers presented a promising antibacterial activity against biofilm H. pylori cells in in vitro conditions.


Asunto(s)
Celulosa/metabolismo , Piruvatos/metabolismo , Sertralina/metabolismo , Biopelículas/crecimiento & desarrollo , Helicobacter pylori/crecimiento & desarrollo , Helicobacter pylori/metabolismo , Helicobacter pylori/ultraestructura , Pruebas de Sensibilidad Microbiana
14.
PLoS One ; 18(5): e0285522, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37172069

RESUMEN

There are many artificial sources of radiofrequency electromagnetic field (RF-EMF) in the environment, with a value between 100 MHz and 6 GHz. The most frequently used signal is with a frequency of around 900 MHz. The direction of these changes positively impacts the quality of life, enabling easy communication from almost anywhere in the world. All living organisms in the world feel the effects of the electromagnetic field on them. The observations regarding the influence of a RF-EMF on honey bees, describing the general impact of RF-EMF on the colony and/or behavior of individual bees, such as reduction in the number of individuals in colonies, extended homing flight duration, decrease in breeding efficiency, changes in flight direction (movement of bees toward the areas affected by RF-EMF), increase in the intensity and frequency of sounds characteristic for those announcing the impending danger. In this work, we describe the changes in the levels of some of the stress-related markers in honey bees exposed to varying intensities and duration of RF-EMF. One-day-old honeybee worker bees were used for the study. The bees were randomly assigned to 9 experimental groups which were exposed to the following 900 MHz EMF intensities: 12 V/m, 28 V/m, and 61 V/m for 15 min, 1 h and 3 h. The control group was not exposed to the RF-EMF. Each experimental group consisted of 10 cages in which were 100 bees. Then, hemolymph was collected from the bees, in which the activity was assessed AST, ALT, ALP, GGTP, and level of nonenzymatic antioxidants albumin, creatinine, uric acid, and urea. Bees were also collected for the analysis of rps5, ppo, hsp10, hsp70, hsp90, and vitellogenin gene expression. Our study shows that exposure to a 900 MHz electromagnetic field induces a response in the honey bees that can be detected in the level of enzyme activity and the expression of stress-related genes. The response is similar to the one previously described as a result of exposition to UVB irradiation and most likely cannot be attributed to increased temperature.


Asunto(s)
Campos Electromagnéticos , Calidad de Vida , Abejas/genética , Animales , Campos Electromagnéticos/efectos adversos , Antioxidantes , Ondas de Radio/efectos adversos , Ácido Úrico
15.
J Med Chem ; 66(21): 14948-14962, 2023 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-37903296

RESUMEN

Healthcare systems heavily rely on antibiotics to treat bacterial infections, but the widespread presence of multidrug-resistant bacteria puts this strategy in danger. Novel drugs capable of overcoming current resistances are needed if our ability to treat bacterial infections is to be maintained. Boron clusters offer a valuable possibility to create a new class of antibiotics and expand the chemical space of antibiotics beyond conventional carbon-based molecules. In this work, we identified two promising structural patterns providing cobalta bis(dicarbollide)(COSAN)-based compounds with potent and selective activity toward Staphylococcus aureus (including clinical strains): introduction of the α-amino acid amide and addition of iodine directly to the metallacarborane cage. Furthermore, we found that proper hydrophilic-lipophilic balance is crucial for the selective activity of the tested compounds toward S. aureus over mammalian cells. The patterns proposed in this paper can be useful in the development of metallacarborane-based antibiotics with potent antibacterial properties and low cytotoxicity.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Animales , Antibacterianos/química , Staphylococcus aureus , Infecciones Estafilocócicas/tratamiento farmacológico , Pruebas de Sensibilidad Microbiana , Mamíferos
16.
Animals (Basel) ; 12(2)2022 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-35049800

RESUMEN

So far, larval rearing in vitro has been an important method in the assessment of bee toxicology, particularly in pesticide risk assessment. However, natural products are increasingly used to control honey bee pathogens or to enhance bee immunity, but their effects on honey bee larvae are mostly unknown. In this study, laboratory studies were conducted to determine the effects of including selected aqueous plant infusions in the diet of honey bee (Apis mellifera L.) larvae in vitro. The toxicity of infusions from three different plant species considered to be medicinal plants was evaluated: tansy (Tanacetum vulgare L.), greater celandine (Chelidonium majus L.), and coriander (Coriandrum sativum L.). The impact of each on the survival of the larvae of honey bees was also evaluated. One-day-old larvae were fed a basal diet consisting of distilled water, sugars (glucose and fructose), yeast extract, and freeze-dried royal jelly or test diets in which distilled water was replaced by plant infusions. The proportion of the diet components was adjusted to the age of the larvae. The larvae were fed twice a day. The experiment lasted seven days. Significant statistical differences in survival rates were found between groups of larvae (exposed or not to the infusions of tansy, greater celandine, and coriander). A significant decrease (p < 0.05) in the survival rate was observed in the group with the addition of a coriander herb infusion compared to the control. These results indicate that plant extracts intended to be used in beekeeping should be tested on all development stages of honey bees.

17.
Front Cell Infect Microbiol ; 12: 868905, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35402304

RESUMEN

It is widely accepted that production of biofilm is a protective mechanism against various type of stressors, including exposure to antibiotics. However, the impact of this structure on the spread of antibiotic resistance in Helicobacter pylori is still poorly understood. Therefore, the aim of the current research was to determine the relationship between biofilm formation and antibiotic resistance of H. pylori. The study was carried out on 24 clinical strains with different resistance profiles (antibiotic-sensitive, mono-resistant, double-resistant and multidrug-resistant) against clarithromycin (CLR), metronidazole (MTZ) and levofloxacin (LEV). Using static conditions and a crystal violet staining method, a strong correlation was observed between biofilm formation and resistance to CLR but not MTZ or LEV. Based on the obtained results, three the strongest and three the weakest biofilm producers were selected and directed for a set of microfluidic experiments performed in the Bioflux system combined with fluorescence microscopy. Under continuous flow conditions, it was observed that strong biofilm producers formed twice as much of biofilm and created significantly more eDNA and in particular proteins within the biofilm matrix when compared to weak biofilm producers. Additionally, it was noticed that strong biofilm producers had higher tendency for autoaggregation and presented morphostructural differences (a greater cellular packing, shorter cells and a higher amount of both OMVs and flagella) in relation to weak biofilm counterparts. In conclusion, resistance to CLR in clinical H. pylori strains was associated with a broad array of phenotypical features translating to the ability of strong biofilm formation.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Biopelículas , Claritromicina/farmacología , Farmacorresistencia Bacteriana , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori/genética , Humanos , Levofloxacino/farmacología , Metronidazol/farmacología , Pruebas de Sensibilidad Microbiana , Microfluídica
18.
Animals (Basel) ; 12(7)2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35405844

RESUMEN

Earth's magnetic field (MF) plays an important role for many species, including the honeybee, in navigation. Nowadays, much larger alternating fields are emitted by miscellaneous electric infrastructure components, such as transformers and power lines, and the environment is therefore polluted by an anthropogenic electromagnetic field, though little is known regarding its impact on living organisms. The behavior of animals is the first and easiest way to establish the impact of stress. It shows if the animal can detect the exposure and react to it. To investigate this, one-day-old bees were exposed to a 50 Hz magnetic field of induction at 1 mT and 1.7 mT for 10 min, 1 h, and 3 h under laboratory conditions. All groups exposed to the magnetic field showed differences in behavioral patterns. What is more, they presented a behavior absent in the control: loss of balance. There were differences, both in the ratio of behaviors and in the number of bouts-exposed bees more often changed behavior. Occurrence of differences is an indication of the reaction of the honeybee organism to the magnetic field. Loss of balance is a disturbing symptom, and behavior changes indicate a disturbance of the honeybee by the electromagnetic field.

19.
Toxics ; 10(10)2022 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-36287870

RESUMEN

The honey bee is an important pollinator. In the environment, it can be exposed to many harmful factors, such as pesticides. Nowadays, attention is paid to evaluating the potentially harmful effects of these substances. This study aimed to evaluate the effect of worst-case environmental concentrations of pesticide mixtures on honey bee survival and selected physiological markers (the activity of ALT, AST, ALP, and GGTP, and the concentration of albumin, creatinine, urea, and uric acid). Pesticides of three different groups (insecticide-acetamiprid, herbicide-glyphosate, and fungicide-tebuconazole) and their mixtures were resolved in 50% (w/v) sucrose solution and given to bees ad libitum. After 24 h, hemolymph was collected. All mixtures caused higher mortality than single pesticides. Pesticides in mixtures caused disturbances in biochemical markers, and in some cases the interaction between pesticides was synergistic. The mixtures had individual effects on physiology, and the results were sensitive to changes in proportions.

20.
BMC Pharmacol Toxicol ; 23(1): 38, 2022 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-35698168

RESUMEN

BACKGROUND: Recently, taurolidine has been intensively studied on a variety of in-vitro cancer cell-lines and first data exhibit encouraging antitumoral effects. While the clinical use of taurolidine is considered, some studies with in-vivo experiments contradict this beneficial effect and even indicate advanced cancer growth. The aim of this study is to further investigate this paradox in-vivo effect by taurolidine and closely analyze the interaction of cancer cells with the surrounding environment following taurolidine exposure. METHODS: HT-29 (ATCC® HTB-38™) cells were treated with taurolidine at different concentrations and oxaliplatin using an in-vitro model. Morphological changes with respect to increasing taurolidine dosage were visualized and monitored using electron microscopy. Cytotoxicity of the agents as well as extent of cellular detachment by mechanical stress was measured for each substance using a colorimetric MTS assay. RESULTS: Both taurolidine and oxaliplatin exhibit cell toxicity on colon cancer cells. Taurolidine reshapes colon cancer cells from round into spheric cells and further induces cluster formation. When exposed to mechanical stress, taurolidine significantly enhances detachment of adherent colon carcinoma cells compared to the control (p < 0.05) and the oxaliplatin group (p < 0.05). This effect is dose dependent. CONCLUSIONS: Beside its cytotoxic effects, taurolidine could also change mechanical interactions of cancer cells with their environment. Local cancer cell conglomerates could be mechanically mobilized and may cause metastatic growth further downstream. The significance of changes in cellular morphology caused by taurolidine as well as its interaction with the microenvironment must be further addressed in clinical cancer therapies. Further clinical studies are needed to evaluate both the safety and efficacy of taurolidine for the treatment of peritoneal surface malignancies.


Asunto(s)
Antineoplásicos , Neoplasias del Colon , Tiadiazinas , Antineoplásicos/uso terapéutico , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Humanos , Oxaliplatino , Taurina/análogos & derivados , Taurina/farmacología , Tiadiazinas/farmacología , Microambiente Tumoral
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