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1.
J Anat ; 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38581181

RESUMEN

This study investigated the pancreas differentiation of two species of gekkotan families-the mourning gecko Lepidodactylus lugubris (Gekkonidae) and the leopard gecko Eublepharis macularius (Eublepharidae)-based on two-dimensional (2D) histological samples and three-dimensional (3D) reconstructions of the position of the pancreatic buds and the surrounding organs. The results showed that at the moment of egg laying, the pancreas of L. lugubris is composed of three distinct primordia: one dorsal and two ventral. The dorsal primordium differentiates earlier than either ventral primordium. The right ventral primordium is more prominent and distinctive, starting to form earlier than the left one. Moreover, at this time, the pancreas of the leopard gecko is composed of the dorsal and right ventral primordium and the duct of the left ventral primordium. It means that the leopard gecko's left primordium is a transitional structure. These results indicate that the early development of the gekkotan pancreas is species specific. The pancreatic buds of the leopard and mourning gecko initially enter the duodenum by separate outlets, similar to the pancreas of other vertebrates. The pancreatic buds (3 of the mourning gecko and 2 of the leopard gecko) fuse quickly and form an embryonic pancreas. After that, the structure of this organ changes. After fusion, the pancreas of both gekkotans comprises four parts: the head of the pancreas (central region) and three lobes: upper, splenic, and lower. This organ develops gradually and is very well distinguished at hatching time. In both gekkotan species, cystic, hepatic, and pancreatic ducts enter the duodenum within the papilla. During gekkotan pancreas differentiation, the connection between the common bile duct and the dorsal pancreatic duct is associated with intestinal rotation, similar to other vertebrates.

2.
Small ; : e2306707, 2024 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-38247201

RESUMEN

In living organisms, carotenoids are incorporated in biomembranes, remarkably modulating their mechanical characteristics, fluidity, and permeability. Significant resonance enhancement of Raman optical activity (ROA) signals of carotenoid chiral aggregates makes resonance ROA (RROA), a highly selective tool to study exclusively carotenoid assemblies in model membranes. Hence, RROA is combined with electronic circular dichroism (ECD), dynamic light scattering (DLS), molecular dynamics, and quantum-chemical calculations to shed new light on the carotenoid aggregation in dipalmitoylphosphatidylcholine (DPPC) liposomes. Using representative members of the carotenoid family: apolar α-carotene and more polar fucoxanthin and zeaxanthin, the authors demonstrate that the stability of carotenoid aggregates is directly linked with their orientation in membranes and the monomer structures inside the assemblies. In particular, polyene chain distortion of α-carotene molecules is an important feature of J-aggregates that show increased orientational freedom and stability inside liposomes compared to H-assemblies of more polar xanthophylls. In light of these results, RROA emerges as a new tool to study active compounds and drugs embedded in membranes.

3.
Int J Mol Sci ; 24(21)2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37958539

RESUMEN

There is some evidence that non-photoactivated psoralens may be active against breast and colon tumor cells. Therefore, we evaluated the antiproliferative, proapoptotic, and anti-migrative effect of 5-methoxypsoralen (5-MOP) isolated from Peucedanum tauricum MB fruits in human colorectal adenocarcinoma (HT-29 and SW620), osteosarcoma (Saos-2 and HOS), and multiple myeloma (RPMI8226 and U266). Dose- and cell-line-dependent effects of 5-MOP on viability and proliferation were observed, with the strongest inhibitory effect against Saos-2 and a moderate effect against the HOS, HT-29, and SW620 cells. Multiple myeloma showed low sensitivity. The high viability of human normal cell cultures (HSF and hFOB) in a wide range of 5-MOP concentrations tested (6.25-100 µM) was confirmed. Moreover, the migration of treated Saos-2, SW620, and HT-29 cell lines was impaired, as indicated via a wound healing assay. Flow cytometry analysis conducted on Saos-2 cells revealed the ability of 5-MOP to block the cell cycle in the G2 phase and trigger apoptosis, which was accompanied by a loss of mitochondrial membrane potential, caspases (-9 and -3) activation, the altered expression of the Bax and Bcl-2 proteins, and decreased AKT phosphorylation. This is the first report evaluating the antiproliferative and antimigratory impact of non-UV-activated bergapten on the abovementioned (except for HT-29) tumor cells, which provides new data on the potential role of 5-MOP in inhibiting the growth of various types of therapeutic-resistant cancers.


Asunto(s)
Neoplasias Óseas , Mieloma Múltiple , Humanos , 5-Metoxipsoraleno/farmacología , Proliferación Celular , Apoptosis , Neoplasias Óseas/patología , Línea Celular Tumoral
4.
Cancers (Basel) ; 15(16)2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37627198

RESUMEN

PURPOSE: To assess the recurrence and birth rates among patients with non-epithelial ovarian cancer. METHODS: The study included 146 patients with germ cell (GCT, n = 84) and sex cord-stromal tumors (SCST, n = 62), who underwent fertility-sparing surgery. Adjuvant chemotherapy was administered to 86 (58.9%) patients. Most cases (133 out of 146) were staged FIGO I. RESULTS: The 5- and 10-year disease-free survival rates were 91% and 83%, respectively. The recurrence risk was not associated with tumor histology, stage or age. Twenty-four months after the treatment, the rate of recurrence was higher than the rate of childbearing. The childbearing rates kept rising after the treatment and exceeded the rate of recurrence after 2 years. The cumulative incidence rates of birth 36, 60 and 120 months after treatment were 13.24%, 20.75%, and 42.37%, respectively. Chemotherapy was not related to childbearing. The patients' age was related to the chance of childbearing. CONCLUSIONS: The prognoses of GCT and SCST are similar. Close follow-ups along with contraception should be offered to women during the first two years after treatment due to the increased risk of recurrence. After this period, relapses are rare and women can safely become pregnant.

5.
Bioorg Chem ; 138: 106608, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37207596

RESUMEN

Here, we rationally designed a human neutrophil elastase (HNE) inhibitors 4a-4f derived from thalidomide. The HNE inhibition assay showed that synthesized compounds 4a, 4b, 4e and 4f demonstrated strong HNE inhibiton properties with IC50 values of 21.78-42.30 nM. Compounds 4a, 4c, 4d and 4f showed a competitive mode of action. The most potent compound 4f shows almost the same HNE inhibition as sivelestat. The molecular docking analysis revealed that the strongest interactions occur between the azetidine-2,4-dione group and the following three aminoacids: Ser195, Arg217 and His57. A high correlation between the binding energies and the experimentally determined IC50 values was also demonstrated. The study of antiproliferative activity against human T47D (breast carcinoma), RPMI 8226 (multiple myeloma), and A549 (non-small-cell lung carcinoma) revealed that designed compounds were more active compared to thalidomide, pomalidomide and lenalidomide used as the standard drugs. Additionally, the most active compound 4f derived from lenalidomide induces cell cycle arrest at the G2/M phase and apoptosis in T47D cells.


Asunto(s)
Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Estructura Molecular , Relación Estructura-Actividad , Talidomida/farmacología , Simulación del Acoplamiento Molecular , Lenalidomida/farmacología , Proteínas Inhibidoras de Proteinasas Secretoras/química , Proteínas Inhibidoras de Proteinasas Secretoras/farmacología , Antineoplásicos/química , Ensayos de Selección de Medicamentos Antitumorales , Proliferación Celular , Línea Celular Tumoral
6.
Artículo en Inglés | MEDLINE | ID: mdl-37107828

RESUMEN

This article aims to identify the impact of the COVID-19 pandemic on the perception of the risk of travel and travel behaviour by Poles. The study was conducted using the survey method and the CAWI technique and was carried out in January 2021. The final research sample consisted of 509 respondents. Tourism has always been exposed to various threats: natural disasters, terrorism, etc. In such cases, tourists choose a different, safe direction. However, in 2020, tourism found itself facing a crisis that brought it to a complete stop worldwide. The spread of the COVID-19 virus and safety concerns, as well as global travel restrictions, led to a change in travel during this time. The results show that the respondents resigned especially from going abroad for security reasons, choosing to rather stay in the country and other places that, from their point of view, were safer places to rest.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Polonia/epidemiología , Pandemias/prevención & control , SARS-CoV-2 , Viaje , Percepción
7.
Polymers (Basel) ; 15(4)2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36850222

RESUMEN

The effectiveness of multifunctional composites that combine a shape-memory polyurethane (PU) matrix with hydroxyapatite (HA) as a bioactive agent and antibiotics molecules results from a specific composite structure. In this study, structure-function correlations of PU-based composites consisting of 3, 5, and 10 (wt%) of HA and (5 wt%) of gentamicin sulfate (GeS) as a model drug were investigated. The performed analysis revealed that increasing HA content up to 5 wt% enhanced hydrogen-bonding interaction within the soft segments of the PU. Differential-scanning-calorimetry (DSC) analysis confirmed the semi-crystalline structure of the composites. Hydroxyapatite enhanced thermal stability was confirmed by thermogravimetric analysis (TGA), and the water contact angle evaluated hydrophilicity. The shape-recovery coefficient (Rr) measured in water, decreased from 94% for the PU to 86% for the PU/GeS sample and to 88-91% for the PU/HA/GeS composites. These values were positively correlated with hydrogen-bond interactions evaluated using the Fourier-transform-infrared (FTIR) spectroscopy. Additionally, it was found that the shape-recovery process initiates drug release. After shape recovery, the drug concentration in water was 17 µg/mL for the PU/GeS sample and 33-47 µg/mL for the PU HA GeS composites. Antibacterial properties of developed composites were confirmed by the agar-diffusion test against Escherichia coli and Staphylococcus epidermidis.

8.
J Invertebr Pathol ; 197: 107884, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36642365

RESUMEN

The cellular immune response of the greater wax moth Galleria mellonella to Pseudomonas aeruginosa exotoxin A was investigated for the first time. The insects were challenged with a sublethal dose of exoA, and then hemocyte parameters were assessed. The analysis showed a statistically significant decrease in the total hemocyte count (THC), which was associated with significant decreases in the number of granulocytes and plasmatocytes. In turn, no statistically significant changes were observed in the number of spherulocytes and oenocytoides. Fluorescent staining indicated that cells collected from the exoA-challenged larvae exhibited features characteristic for apoptotic and autophagic cell death, e.g. cytoplasm vacuolization and chromatin condensation. The flow cytometry analysis revealed a significant increase in the number of phosphatidylserine- and active caspase 3-positive hemocytes challenged with exoA, which proved apoptosis induction. Our results will help in understanding the role of exotoxin A during P. aeruginosa infections not only in insects but also in mammals, including humans.


Asunto(s)
Hemocitos , Mariposas Nocturnas , Humanos , Animales , Factores de Virulencia , Larva , Insectos , Apoptosis , Pseudomonas aeruginosa , Mamíferos , Exotoxina A de Pseudomonas aeruginosa
9.
Materials (Basel) ; 17(1)2023 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-38203944

RESUMEN

Given the mechanical hazards occurring in the workplace, cut resistance is a particularly important protective parameter. 3D printing is an innovative technology that has recently garnered great interest. It enables the creation of functional polymeric materials with metal reinforcement for use in cut-resistant gloves. The present study characterized and tested 3D-printed polymeric materials intended for such applications. The materials were made from commercially available 3D printing polymer filaments. Metallic reinforcement (stainless steel wire with a diameter of 0.04 mm) was added to the two selected materials (thermoplastic polyurethane and FiberFlex30D). Tests have shown that materials containing metallic reinforcement demonstrate higher mechanical resistance. Cut resistance increased by 70%, and the force needed to tear the sample increased by over 20% compared to the pure polymer. The presence of metallic reinforcement strengthens the structure of the material and changes the cracking mechanism. The tearing occurs in the test area, not in the bell area. These findings demonstrate the feasibility of applying functional 3D-printed polymeric materials with metal reinforcement in cut-resistant gloves.

10.
J Chem Phys ; 157(24): 244502, 2022 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-36586985

RESUMEN

The T1 relaxation time measured in nuclear magnetic resonance experiments contains information about electric field gradient (EFG) fluctuations around a nucleus, but computer simulations are typically required to interpret the underlying dynamics. This study uses classical molecular dynamics (MD) simulations and quantum chemical calculations, to investigate EFG fluctuations around a Na+ ion dissolved in the ionic liquid 1-ethyl 3-methylimidazolium tetrafluoroborate, [Im21][BF4], to provide a framework for future interpretation of NMR experiments. Our calculations demonstrate that the Sternheimer approximation holds for Na+ in [Im21][BF4], and the anti-shielding coefficient is comparable to its value in water. EFG correlation functions, CEFG(t), calculated using quantum mechanical methods or from force field charges are roughly equivalent after 200 fs, supporting the use of classical MD for estimating T1 times of monatomic ions in this ionic liquid. The EFG dynamics are strongly bi-modal, with 75%-90% of the de-correlation attributable to inertial solvent motion and the remainder to a highly distributed diffusional processes. Integral relaxation times, ⟨τEFG⟩, were found to deviate from hydrodynamic predictions and were non-linearly coupled to solvent viscosity. Further investigation showed that Na+ is solvated by four tetrahedrally arranged [BF4]- anions and directly coordinated by ∼6 fluorine atoms. Exchange of [BF4]- anions is rare on the 25-50 ns timescale and suggests that motion of solvent-shell [BF4]- is the primary mechanism for the EFG fluctuations. Different couplings of [BF4]- translational and rotational diffusion to viscosity are shown to be the source of the non-hydrodynamic scaling of ⟨τEFG⟩.

11.
Front Chem ; 10: 1028912, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36458156

RESUMEN

The global need to expand the design of energy-storage devices led to the investigation of alkali metal - Ionic Liquid (IL) mixtures as a possible class of electrolytes. In this study, 1D and 2D Nuclear Magnetic Resonance (NMR) and Electrochemical Impedance Spectroscopy (EIS) as well as Molecular Dynamics (MD) simulations were used to study the intermolecular interactions in imidazolium-based IL - water - alkali halide ternary mixtures. The 1H and 23Na 1D and 1H DOSY NMR spectra revealed that the presence of small quantities of NaCl does not influence the aggregation of water molecules in the IL nano-domains. The order of adding ionic compounds to water, as well as the certain water and NaCl molecular ratios, lead to the formation of isolated water clusters. Two ternary solutions representing different orders of compounds mixing (H2O+ IL + NaCl or H2O+ NaCl + IL) showed a strong dependence of the initial solvation shell of Na+ and the self-clustering of water. Furthermore, the behaviour of water was found to be independent from the conditions applied during the solution preparation, such as temperature and/or duration of stirring and aging. These findings could be confirmed by large differences in the amount of ionic species, observed in the ternary solutions and depending on the order of mixing/solute preparation.

12.
JIMD Rep ; 63(5): 508-517, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36101827

RESUMEN

Symptoms of Wilson disease (WD) vary and additional factors such as autoimmunity may play an important role in WD pathogenesis. The presence of antinuclear antibodies (ANA), anti-neutrophil cytoplasmic antibodies, neuronal surface antibodies, and onconeural antibodies in WD was investigated using standardized indirect immunofluorescence assays and Western Blot analysis. The presence of all studied autoantibodies was higher in WD patients in comparison to healthy subjects, but there was no statistically significant difference in autoantibodies frequency according to disease manifestation. D-penicillamine treatment was associated with a higher presence of ANA than zinc sulfate but without an increase in autoimmune diseases rate.

13.
Int J Mol Sci ; 23(14)2022 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-35886913

RESUMEN

A series of 3,3-diethylazetidine-2,4-dione based thiazoles 3a-3j were designed and synthesized as new human neutrophil elastase (HNE) inhibitors in nanomolar range. The representative compounds 3c, 3e, and 3h exhibit high HNE inhibitory activity with IC50 values of 35.02-44.59 nM, with mixed mechanism of action. Additionally, the most active compounds 3c and 3e demonstrate high stability under physiological conditions. The molecular docking study showed good correlation of the binding energies with the IC50 values, suggesting that the inhibition properties are largely dependent on the stage of ligand alignment in the binding cavity. The inhibition properties are correlated with the energy level of substrates of the reaction of ligand with Ser195. Moreover, most compounds showed high and broad-spectrum antiproliferative activity against human leukemia (MV4-11), human lung carcinoma (A549), human breast adenocarcinoma (MDA-MB-231), and urinary bladder carcinoma (UMUC-3), with IC50 values of 4.59-9.86 µM. Additionally, compounds 3c and 3e can induce cell cycle arrest at the G2/M phase and apoptosis via caspase-3 activation, leading to inhibition of A549 cell proliferation. These findings suggest that these new types of drugs could be used to treat cancer and other diseases in which immunoreactive HNE is produced.


Asunto(s)
Antineoplásicos , Carcinoma , Proteínas Inhibidoras de Proteinasas Secretoras , Tiazoles , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Ligandos , Simulación del Acoplamiento Molecular , Estructura Molecular , Relación Estructura-Actividad , Tiazoles/química , Tiazoles/farmacología
14.
Int J Mol Sci ; 23(12)2022 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-35743158

RESUMEN

Many organophosphorus compounds (OPs), especially various α-aminophosphonates, exhibit anti-cancer activities. They act, among others, as inhibitors of the proteases implicated in cancerogenesis. Thesetypes of inhibitors weredescribed, e.g., for neutral endopeptidase (NEP) expressed in different cancer cells, including osteosarcoma (OS). The aim of the present study isto evaluate new borane-protected derivatives of phosphonous acid (compounds 1-7) in terms of their drug-likeness properties, anti-osteosarcoma activities in vitro (against HOS and Saos-2 cells), and use as potential NEP inhibitors. The results revealed that all tested compounds exhibited the physicochemical and ADME properties typical for small-molecule drugs. However, compound 4 did not show capability of blood-brain barrier penetration (Lipinski and Veber rules;SwissAdme tool). Moreover, the α-aminophosphonite-boranes (compounds 4-7) exhibited stronger anti-proliferative activity against OS cells than the other phosphonous acid-borane derivatives (compounds 1-3),especially regarding HOS cells (MTT assay). The most promising compounds 4 and 6 induced apoptosis through the activation of caspase 3 and/or cell cycle arrest at the G2 phase (flow cytometry). Compound 4 inhibited the migration and invasiveness of highly aggressive HOS cells (wound/transwell and BME-coated transwell assays, respectively). Additionally, compound 4 and, to a lesser extent, compound 6 inhibited NEP activity (fluorometric assay). This activity of compound 4 was involved in its anti-proliferative potential (BrdU assay). The present study shows that compound 4 can be considered a potential anti-osteosarcoma agent and a scaffold for the development of new NEP inhibitors.


Asunto(s)
Antineoplásicos , Neoplasias Óseas , Boranos , Osteosarcoma , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/metabolismo , Boranos/farmacología , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Humanos , Neprilisina/farmacología , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/metabolismo
15.
Chemphyschem ; 23(10): e202200283, 2022 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-35583322

RESUMEN

The front cover artwork is provided by Patryk Palenque Marcinkowski. The image shows a glycerol-choline network accommodating water molecules over time. The glycerol molecules are represented as pandas adapting to the change. Read the full text of the Research Article at 10.1002/cphc.202100806.


Asunto(s)
Disolventes Eutécticos Profundos , Glicerol , Colina/química , Glicerol/química , Enlace de Hidrógeno , Solventes/química
16.
Pol Przegl Chir ; 95(1): 1-5, 2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-36806167

RESUMEN

Pancreatic cancer, despite significant progress in diagnosis and treatment still has poor prognosis. Surgical treatment remains the only cure option. Unfortunately, the percentage of patients in whom radical tumor removal is possible is less than 20%. Resection procedures are burdened with a high degree of difficulty, as well as a high complication rate. One of the important factors contributing to the high morbidity of the perioperative period is malnutrition, and rapidly progressing malnutrition which occurs in about 85% of pancreatic cancer patients. Abnormal nutritional status is closely related to a change in the composition in the body.The aim of the study was to determine the changes in the body composition of patients with pancreatic cancer and their consequences based on the results of the current research.The available reports have shown that the body composition of a patient with pancreatic cancer undoubtedly changes and is dependent on the stage, location and type of cancer. Furthermore, the fact if antitumor treatment is applied or not, also plays a significant role.It appears that in patients with pancreatic cancer, weight loss with a decline in parameters such as body fat and skeletal muscle mass appears early and worsens as the tumor grows and the disease progresses. The above data suggest that knowing the patient's body composition and observing its changes may be a prognostic factor for survival and the occurrence of complications. Additionally, there are reports that dosing chemotherapy based on body composition rather than conventional measures can help reduce the toxicity of the treatment. Therefore, knowing the patient's body composition seems to be an important aspect.


Asunto(s)
Desnutrición , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/cirugía , Composición Corporal , Desnutrición/etiología , Estado Nutricional , Neoplasias Pancreáticas
17.
Artículo en Inglés | MEDLINE | ID: mdl-36612470

RESUMEN

A key property in the manufacture of toecaps for protective footwear is resistance to impacts, deformations, and cracking, as the resulting defects may lead to serious workplace accidents involving the lower extremities. The present paper proposes a new approach to qualitative verification of toecap design based on numerical simulations of impact tests. Computational experiments were conducted for toecaps made from different materials (AISI 10450, S235, S355 and A36 steels, as well as Lexan polycarbonate) and characterized by different geometries, which were recreated by 3D scanning. The impact resistance of the toecaps was analyzed using a numerical model simulating an experimental impact test. The results were used to determine the location of critical stresses and to plot equivalent stress maps for the studied toecaps. The finite element analysis of the impact tests was carried out with an explicit elastoplastic finite element code: ANSYS (Ansys, Inc., Canonsburg, PA, USA) with the Explicit Dynamics module of the Workbench solver. The presented analysis of the impact resistance of toecaps by the finite element method for impact simulation may be used to optimize the spatial geometry of toecaps and to verify the construction of toecaps and the material deformations that may occur. In addition, it could eliminate unsuitable materials that are likely to undergo dangerous deformations, and draw attention to the deformation caused by the impact of the toecaps used in footwear in the working environment.


Asunto(s)
Extremidad Inferior , Análisis de Elementos Finitos , Simulación por Computador
18.
Molecules ; 28(1)2022 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-36615293

RESUMEN

Since natural substances are widely explored as epigenetic modulators of gene expression and epigenetic abnormalities are important causes of cancerogenesis, factors with pro-tumor activities subjected to epigenetic control, e.g., neutral endopeptidase (NEP, neprilysin), are promising anticancer targets for potential therapies acting via epigenetic regulation of gene expression. Alpha-ketoglutarate (AKG) is a naturally occurring co-substrate for enzymes involved in histone and DNA demethylation with suggested anti-cancer activity. Hence, we investigated a potential effect of AKG on the NEP expression in cells derived from various cancers (cervical, colon, osteosarcoma) and normal epithelial cells and osteoblasts. Moreover, the overall methylation status of histone H3 was explored to establish the molecular target of AKG activity. Additionally, it was investigated whether AKG in combination with thiorphan (NEP specific inhibitor) exhibited enhanced anticancer activity. The results revealed that AKG downregulated the expression of NEP at the protein level only in highly aggressive osteosarcoma HOS cells (flow cytometry and fluorometric assays), and this protease was found to be involved in AKG-induced growth inhibition in osteosarcoma cells (siRNA NEP silencing, BrdU assay, flow cytometry). Unexpectedly, AKG-induced hypermethylation of H3K27 in HOS cells, which was partially dependent on EZH2 activity. However, this effect was not implicated in the AKG-induced NEP downregulation (flow cytometry). Finally, the combined treatment with AKG and thiorphan was shown to significantly enhance the growth inhibitory potential of each one towards HOS cells (BrdU assay). These preliminary studies have shown for the first time that the downregulation of NEP expression is a promising target in therapies of NEP-implicating HOS cells. Moreover, this therapeutic goal can be achieved via AKG-induced downregulation of NEP and synergistic activity of AKG with thiorphan, i.e., a NEP specific inhibitor. Furthermore, this study has reported for the first time that exogenous AKG can influence the activity of histone methyltransferase, EZH2. However, this issue needs further investigation to elucidate the mechanisms of this phenomenon.


Asunto(s)
Osteosarcoma , Tiorfan , Humanos , Tiorfan/metabolismo , Neprilisina , Ácidos Cetoglutáricos/farmacología , Epigénesis Genética , Bromodesoxiuridina , Histonas/metabolismo , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/genética
19.
Materials (Basel) ; 14(22)2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34832278

RESUMEN

The objective of the present work was to evaluate the effects of different types of particles added to a polymer paste applied onto a textile carrier on the cut resistance of the resulting material. Knitted aramid textile samples were coated in laboratory conditions using a polymer paste that was functionalized with 12 types of reinforcing particles of different chemical compositions and size fractions. Cut resistance was tested in accordance with the standard EN ISO 13997:1999 and the results were subjected to statistical analysis. The effects of additive particles on the microstructure of the polymeric layer were assessed by means of scanning electron microscopy. The type and size of the particles affected the cut resistance of the functionalized knitted fabric. They were also found to change the morphology of the porous structure. Composite coatings containing the smallest additive particles exhibited the best cut resistance properties.

20.
Viruses ; 13(7)2021 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-34372538

RESUMEN

Bacterial surface structures of a proteinic nature and glycoconjugates contribute to biofilm formation and provide shields to host defense mechanisms (e.g., the complement system and phagocytosis). A loss or alteration of these molecules, leading to phage resistance, could result in fewer virulent bacteria. In this study, we evaluate the biology and phenotype changes in Pseudomonas aeruginosa PAO1 phage-resistant clones, which emerge in phage-treated biofilms. We characterize these clones for phage-typing patterns, antibiotic resistance, biofilm formation, pathogenicity, and interactions with the innate immune system. Another important question that we address is whether phage-resistant mutants are also generated incidentally, despite the phage treatment-selective pressure, as the natural adaptation of the living biofilm population. It is found that the application of different phages targeting a particular receptor selects similar phage resistance patterns. Nevertheless, this results in a dramatic increase in the population heterogeneity, giving over a dozen phage-typing patterns, compared to one of the untreated PAO1 sessile forms. We also confirm the hypothesis that "phage-resistant bacteria are more susceptible to antibiotics and host-clearance mechanisms by the immune system". These findings support phage application in therapy, although the overall statement that phage treatment selects the less virulent bacterial population should be further verified using a bigger collection of clinical strains.


Asunto(s)
Farmacorresistencia Microbiana/genética , Fagos Pseudomonas/genética , Pseudomonas aeruginosa/virología , Antibacterianos/farmacología , Bacteriófagos/genética , Biopelículas/crecimiento & desarrollo , Farmacorresistencia Microbiana/fisiología , Humanos , Terapia de Fagos/métodos , Fagocitosis/genética , Fenotipo , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Virulencia
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