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1.
Molecules ; 28(9)2023 Apr 28.
Article de Anglais | MEDLINE | ID: mdl-37175210

RÉSUMÉ

Four compounds with lactone moiety were synthesized from chalcone 1 in three- or four-step synthesis. γ-Bromo-δ-lactone 5 was the only product of bromolactonization of acid 4 whereas bromolactonization of ester 3, apart from lactone 5 also afforded its isomer 6 and two diastereoisomeric δ-hydroxy-γ-lactones 7 and 8. Lactone 8 was also obtained in 88% yield as a product of simultaneous dehalogenation and translactonization of γ-bromo-δ-lactone 5 by Penicillum frequentans AM 359. Chalcone-derived lactones 5-8 were subjected to the tests on antimicrobial activity and the results compared with activity of starting chalcone 1. Obtained lactones 5-8 in most cases limited the growth of tested bacterial and fungal strains. The highest activity was found for δ-hydroxy-γ-lactone 8 which completely inhibited the growth of Staphylococcus aureus, Fusarium graminearum, Aspergillus niger, and Alternaria sp. The introduction of lactone moiety into chalcone scaffold significantly improved antimicrobial activity of the compound: γ-bromo-δ-lactone 6 and δ-hydroxy-γ-lactone 8 were significantly stronger growth inhibitors of S. aureus and F. graminearum. In the case of the latter, a clear positive effect of the lactone function on the antifungal activity was also observed for γ-bromo-δ-lactone 5.


Sujet(s)
Antifongiques , Chalcones , Antifongiques/pharmacologie , Chalcones/pharmacologie , Lactones/pharmacologie , Lactones/métabolisme , Staphylococcus aureus/métabolisme , Antibactériens/pharmacologie , Biotransformation
2.
Molecules ; 27(22)2022 Nov 19.
Article de Anglais | MEDLINE | ID: mdl-36432140

RÉSUMÉ

Designing catalyst systems based on transition metal ions and activators using the principles of green chemistry is a fundamental research goal of scientists due to the reduction of poisonous solvents, metal salts and organic ligands released into the environment. Urgent measures to reduce climate change are in line with the goals of sustainable development and the new restrictive laws ordained by the European Union. In this report, we attempted to use known oxovanadium(IV) green complex compounds with O, N and S donor ligands, i.e., [VO(TDA)phen] • 1.5 H2O (TDA = thiodiacetate), (phen = 1,10-phenanthroline), oxovanadium(IV) microclusters with 2-phenylpyridine (oxovanadium(IV) cage), [VOO(dipic)(2-phepyH)] • H2O (dipic = pyridine-2,6-dicarboxylate anion), (2-phepyH = 2-phenylpyridine), [VO(dipic)(dmbipy)] • 2H2O (dmbipy = 4,4'-dimethoxy-2,2'-dipyridyl) and [VO(ODA)(bipy)] • 2 H2O (ODA = oxydiacetate), (bipy = 2,2'-bipyridine), as precatalysts in oligomerization reactions of 3-buten-2-ol, 2-propen-1-ol, 2-chloro-2-propen-1-ol and 2,3-dibromo-2-propen-1-ol. The precatalysts, in most cases, turned out to be highly active because the catalytic activity exceeded 1000 g mmol-1·h-1. In addition, the oligomers were characterized by Fourier-transform infrared spectroscopy (FTIR), matrix-assisted laser desorption/ionization (MALDI-TOF-MS), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques.


Sujet(s)
Alcènes , Phénanthrolines , Ligands , Phénanthrolines/composition chimique
3.
Sci Rep ; 12(1): 18284, 2022 10 31.
Article de Anglais | MEDLINE | ID: mdl-36316430

RÉSUMÉ

Helicobacter pylori (Hp) Gram-negative bacteria cause gastritis or gastric ulcers. They may be involved in the development of systemic diseases i.e. coronary heart disease (CHD). Both Hp infection and CHD are related to inflammation accompanied by C-reactive protein (CRP), tumor necrosis factor alfa (TNF-α) and homocysteine. Low density lipoprotein (LDL) and triglicerides are a classic risk factors of CHD. Infrared spectroscopy has been introduced for monitoring chronic infections or endogenous disorders using specific absorption bands for biocomponents typed as diagnostic markers. In this study we selected specific motives of infrared radiation (IR) spectra for the sera from CHD patients infected with Hp. In total 141 sera were used: 90 from patients with CHD, all Hp positive, and 51 from healthy donors, 32 Hp negative and 21 Hp positive. Hp status was evaluated by anti-Hp IgG antibodies and/or 13C urea breath testing. IR spectra were measured using FT-IR/FT-NIR Spectrum 400 spectrometer (PerkinElmer) chemometrically analyzed using artificial neural networks and they showed differences in absorption bands corresponding to triglicerides, CRP, homocysteine, LDL and TNF-α, and selected component groups between CHD patients infected with Hp vs healthy uninfected donors (96.15% accuracy). Triglicerides and CRP were the best biomarkers linking Hp infection with CHD.


Sujet(s)
Maladie coronarienne , Gastrite , Infections à Helicobacter , Helicobacter pylori , Humains , Infections à Helicobacter/complications , Infections à Helicobacter/diagnostic , Infections à Helicobacter/microbiologie , Helicobacter pylori/métabolisme , Facteur de nécrose tumorale alpha , Spectroscopie infrarouge à transformée de Fourier , Gastrite/diagnostic , Marqueurs biologiques , Protéine C-réactive/métabolisme , , Homocystéine
4.
Sci Rep ; 11(1): 15212, 2021 Jul 26.
Article de Anglais | MEDLINE | ID: mdl-34312412

RÉSUMÉ

The contemporary search for new catalysts for olefin oligomerization and polymerization is based on the study of coordinating compounds and/or organometallic compounds as post-metallocene catalysts. However known catalysts are suffered by many flaws, among others unsatisfactory activity, requirement of high pressure or instability at high temperatures. In this paper, we present a new catalyst i.e. the crystalline complex compound possesing high catalytic activity in the oligomerization of olefins, such as 2-chloro-2-propen-1-ol and ethylene under very mild conditions (room temperature, 0.12 bar for ethylene oligomerization, atmospheric pressure for 2-chloro-2-propen-1-ol oligomerization). New material-Cat-CrNP ([nitrilotriacetato-1,10-phenanthroline]chromium(III) tetrahydrate) has been obtained as crystalline form of the nitrilotriacetate complex compound of chromium(III) with 1,10-phenanthroline and characterized in terms of its crystal structure by the XRD method and by multi-analytical investigations towards its physicochemical propeties The yield of catalytic oligomerization over Cat-CrNP reached to 213.92 g · mmol-1 · h-1· bar-1 and 3232 g · mmol-1 · h-1 · bar-1 for the 2-chloro-2-propen-1-ol and ethylene, respectively. Furthemore, the synthesis of Cat-CrNP is cheap, easy to perform and solvents used during preparation are environmentally friendly.

5.
J Clin Med ; 9(12)2020 Nov 27.
Article de Anglais | MEDLINE | ID: mdl-33260854

RÉSUMÉ

Helicobacter pylori infections causing gastroduodenal disorders are a common medical problem. The aim of this study was to determine the specific motives of infrared spectroscopy (IR) spectra of sera from H. pylori-infected and uninfected children applied to investigate quantitatively-selected soluble biomarkers correlated with H. pylori infection in children and presumable consequent delayed growth. Sera from 41 children infected with H. pylori (Hp(+)) and 43 uninfected (Hp(-)) under the care of the Polish Mother's Hospital in Lodz, Poland, were analyzed. The H. pylori status was confirmed by gastroscopy, 13C urea breath testing, and anti-H. pylori IgG antibodies. Infrared spectra were measured using an FTIR/FT-NIR Spectrum 400 spectrometer (PerkinElmer). The IR spectrum was measured in the wavenumber range 3000-750 cm-1 and subjected to mathematical calculation of the first derivative. Based on the chi-square test, 10 wavenumbers of spectra correlating with H. pylori infection were selected for use in designing an artificial neural network. Ten parts of the IR spectra correlating with H. pylori infection were identified in the W2 and W3 windows associated mainly with proteins and the W4 window related to nucleic acids and hydrocarbons. Artificial neural networks for H. pylori infection were developed based on chemometric data. By mathematical modeling, children were classified towards H. pylori infection in conjunction with elevated levels of selected biomarkers in serum potentially related to growth retardation. The study concludes that IR spectroscopy and artificial neural networks may help to confirm H. pylori-driven growth disorders in children.

6.
Materials (Basel) ; 13(13)2020 Jul 06.
Article de Anglais | MEDLINE | ID: mdl-32640568

RÉSUMÉ

The paper deals with the design of the stacking sequence of layers in the laminate beams with open-cross sections in order to create the desired behavior in the post-buckling range. Laminate beams with channel and lipped channel cross-sections made of glass fiber reinforced polymer (GFRP) laminate with different layer arrangements (symmetrical and nonsymmetrical) have been considered. In case of the nonsymmetrical stacking sequences, hygro-thermally curvature stable (HTCS) laminates have been taken into account. Pure bending was assumed as the type of load. In the case of beams with open cross-sections, this load type can cause the lateral-distortional buckling mode. A parametric study was performed to analyze the influence of layer arrangement on post-buckling behavior. The finite element method was used to developed numerical models and conduct simulations. Additionally, the experimental tests of the channel section beams were performed in order to validate the developed numerical models.

7.
Int J Mol Sci ; 22(1)2020 Dec 30.
Article de Anglais | MEDLINE | ID: mdl-33396581

RÉSUMÉ

Infections due to Gram-negative bacteria Helicobacter pylori may result in humans having gastritis, gastric or duodenal ulcer, and even gastric cancer. Investigation of quantitative changes of soluble biomarkers, correlating with H. pylori infection, is a promising tool for monitoring the course of infection and inflammatory response. The aim of this study was to determine, using an experimental model of H. pylori infection in guinea pigs, the specific characteristics of infrared spectra (IR) of sera from H. pylori infected (40) vs. uninfected (20) guinea pigs. The H. pylori status was confirmed by histological, molecular, and serological examination. The IR spectra were measured using a Fourier-transform (FT)-IR spectrometer Spectrum 400 (PerkinElmer) within the range of wavenumbers 3000-750 cm-1 and converted to first derivative spectra. Ten wavenumbers correlated with H. pylori infection, based on the chi-square test, were selected for a K-nearest neighbors (k-NN) algorithm. The wavenumbers correlating with infection were identified in the W2 and W3 windows associated mainly with proteins and in the W4 window related to nucleic acids and hydrocarbons. The k-NN for detection of H. pylori infection has been developed based on chemometric data. Using this model, animals were classified as infected with H. pylori with 100% specificity and 97% sensitivity. To summarize, the IR spectroscopy and k-NN algorithm are useful for monitoring experimental H. pylori infection and related inflammatory response in guinea pig model and may be considered for application in humans.


Sujet(s)
Anticorps antibactériens/immunologie , Infections à Helicobacter/immunologie , Helicobacter pylori/immunologie , Inflammation/immunologie , Spectroscopie infrarouge à transformée de Fourier/méthodes , Cellules A549 , Algorithmes , Animaux , Anticorps antibactériens/sang , Protéine C-réactive/métabolisme , Lignée cellulaire tumorale , Modèles animaux de maladie humaine , Infections à Helicobacter/sang , Infections à Helicobacter/microbiologie , Helicobacter pylori/physiologie , Humains , Immunoglobuline G/sang , Immunoglobuline G/immunologie , Immunoglobuline M/sang , Immunoglobuline M/immunologie , Inflammation/sang , Inflammation/microbiologie , Mâle , Facteur de nécrose tumorale alpha/sang
8.
Molecules ; 24(10)2019 May 15.
Article de Anglais | MEDLINE | ID: mdl-31096674

RÉSUMÉ

This paper presents the synthesis of γ -halo- δ -lactones, δ -iodo- γ -lactones and δ -hydroxy- γ -lactones from readily available organic substrates such as trans-crotonaldehyde and aryl bromides. Crystal structure analysis was carried out for lactones that were obtained in crystalline form. All halo- δ -lactones and δ -hydroxy- γ -lactones were highly cytotoxic against gastric cancer AGS cells with I C 50 values in the range of 0.0006-0.0044 mM. Some lactones showed high bactericidal activity against E. coli ATCC 8739 and S. aureus ATCC 65389, which reduced the number of CFU/mL by 70-83% and 87% respectively.


Sujet(s)
Antinéoplasiques/composition chimique , Antinéoplasiques/pharmacologie , Lactones/composition chimique , Lactones/pharmacologie , Animaux , Antibactériens/composition chimique , Antibactériens/pharmacologie , Lignée cellulaire , Relation dose-effet des médicaments , Humains , Hydrolyse , Souris , Modèles moléculaires , Conformation moléculaire , Structure moléculaire , Relation structure-activité
9.
J Spec Oper Med ; 18(4): 148, 2018.
Article de Anglais | MEDLINE | ID: mdl-30566741
10.
ChemistryOpen ; 7(7): 543-550, 2018 Jul.
Article de Anglais | MEDLINE | ID: mdl-30038879

RÉSUMÉ

A new four-step pathway for the synthesis of γ-halo-δ-lactones is described from simple, commercially available substrates: aryl bromides and 3-methyl crotonaldehyde. The halogenolactonization reaction of ß,δ-substituted, γ,δ-unsaturated carboxylic acid 4 a-c is regio- and stereoselective and gives only the trans-isomers of lactones 5 a-c, 6 a-c, and 7 a-c. The structures of all synthesized compounds were confirmed by using spectroscopic methods. For bromolactone, containing a naphthyl moiety in the structure, crystallographic analysis was also performed. The lactones were tested for their cytotoxic activity against L929 cell lines (mouse fibroblasts) and antibacterial activity against Escherichia coli strains ATCC 8739 and Staphylococcus aureus ATCC 65389. Compounds 5 a, 5 c, 7 a, and 7 b statistically significantly inhibited the metabolic activity of mouse fibroblasts L929. Compounds 5 b and 6 a were not cytotoxic towards L929 cells, but showed moderate bactericidal properties.

11.
J Spec Oper Med ; 18(1): 145, 2018.
Article de Anglais | MEDLINE | ID: mdl-29533451
14.
Mol Biol Rep ; 43(12): 1321-1326, 2016 Dec.
Article de Anglais | MEDLINE | ID: mdl-27640014

RÉSUMÉ

Rheumatoid arthritis is an autoimmune inflammatory disease leading to joint cartilage, bone degradation and limitation of mobility. Diagnosis of RA is difficult and complex. There are also no effective methods for clear discrimination between RA patients and non-RA individuals. In this work we use IR spectroscopy to differentiate RA patients and blood donors' sera. We found differences between investigated sera (RA and non-RA) in range of 3000-2800 and 1800-800 cm-1 (W1-W5 regions). Based on mathematical analysis we developed a K-NN model characterized by 85 % of sensitivity and 100 % of specificity. Also we found that, wavenumber 1424 cm-1, comprising in W3 region, was the most effective in human sera distinguishing. We conclude that IR spectroscopy may serve as a fast and easy method useful in RA serology.


Sujet(s)
Polyarthrite rhumatoïde/diagnostic , Adulte , Sujet âgé , Polyarthrite rhumatoïde/sang , Analyse chimique du sang , Humains , Adulte d'âge moyen , Projets pilotes , Spectroscopie infrarouge à transformée de Fourier , Jeune adulte
15.
Innate Immun ; 22(5): 325-35, 2016 07.
Article de Anglais | MEDLINE | ID: mdl-27189426

RÉSUMÉ

Proteus spp. strains are some of the most important pathogens associated with complicated urinary tract infections and bacteremia affecting patients with immunodeficiency and long-term urinary catheterization. For epidemiological purposes, various molecular typing methods have been developed for this pathogen. However, these methods are labor intensive and time consuming. We evaluated a new method of differentiation between strains. A collection of Proteus spp. strains was analyzed by attenuated total reflectance Fourier transform infrared (ATR FT-IR) spectroscopy in the mid-infrared region. ATR FT-IR spectroscopy used in conjunction with a diamond ATR accessory directly produced the biochemical profile of the surface chemistry of bacteria. We conclude that a combination of ATR FT-IR spectroscopy and mathematical modeling provides a fast and reliable alternative for discrimination between Proteus isolates, contributing to epidemiological research.


Sujet(s)
Bactériémie/diagnostic , Infections à Proteus/diagnostic , Proteus mirabilis/métabolisme , Spectroscopie infrarouge à transformée de Fourier/méthodes , Infections urinaires/diagnostic , Animaux , Études de faisabilité , Humains , Lipopolysaccharides/immunologie , Modèles théoriques , Pologne/épidémiologie , Infections à Proteus/épidémiologie , Proteus mirabilis/classification , Spécificité d'espèce
16.
J Basic Microbiol ; 56(8): 922-8, 2016 Aug.
Article de Anglais | MEDLINE | ID: mdl-26972384

RÉSUMÉ

The pathogenicity of entomopathogenic nematodes (EPNs) depends directly on the presence of bacteria in the nematode digestive tracts. Based on 16S rRNA and MALDI-TOF analyses 20 isolated bacteria were assigned to 10 species with 10 isolates classified as Pseudomonas ssp. Six strains (30%) show ureolytic activity on Christensen medium. Spectroscopic analysis of the strains showed that the ureolytic activity is strongly correlated with the following wavenumbers: 935 cm(-1) in window W4, which carries information about the bacterial cell wall construction and 1158 cm(-1) in window W3 which corresponds to proteins in bacterial cell. A logistic regression model designed on the basis of the selected wavenumbers differentiates ureolytic from non-ureolytic bacterial strains with an accuracy of 100%. Spectroscopic studies and mathematical analyses made it possible to differentiate EPN-associated Pseudomonas sp. strains from clinical Pseudomonas aeruginosa PAO1. These results suggest, that infrared spectra of EPN-associated Pseudomonas sp. strains may reflect its adaptation to the host.


Sujet(s)
Insectes/parasitologie , Nematoda/microbiologie , Pseudomonas/métabolisme , Urée/métabolisme , Animaux , Pseudomonas/génétique , Pseudomonas/isolement et purification
17.
J Incl Phenom Macrocycl Chem ; 81(3-4): 357-365, 2015.
Article de Anglais | MEDLINE | ID: mdl-25750585

RÉSUMÉ

Synthesis of new podands from resorcinarene and diethylene glycols are reported. The binding properties of these podands with alkali metal cations was studied by means of ESI-MS. The experimental results for podands with long diethylene glycol arms show the stable inclusion complexes with one or two metal cations and high affinity for sodium and potassium ions. This podands under appropriate conditions can thus form a sufficiently long cavity to accommodate more than one metal ion inside without disturbance of the axial symmetry like an ion channel. Podand with shorter arms, obtained from ethylene glycol form complexes with 1:1 stoichiometry and also readily dimers or trimers. In the presence of alkali metal cations this podand selectively binds cesium ions. The significant affinity of synthesized podands for the biologically important alkali metal ions may affect living organisms. Antibacterial activities were tested with series of Gram-positive and Gram-negative bacteria.

18.
Acta Biochim Pol ; 60(4): 713-8, 2013.
Article de Anglais | MEDLINE | ID: mdl-24432322

RÉSUMÉ

BACKGROUND & AIMS: Infrared spectroscopy is an increasingly common method for bacterial strains' testing. For the analysis of bacterial IR spectra, advanced mathematical methods such as artificial neural networks must be used. The combination of these two methods has been used previously to analyze taxonomic affiliation of bacteria. The aim of this study was the classification of Escherichia coli strains in terms of susceptibility/resistance to cephalothin on the basis of their infrared spectra. The infrared spectra of 109 uropathogenic E. coli strains were measured. These data are used for classification of E. coli strains by using designed artificial neural networks. RESULTS: The most efficient artificial neural networks classify the E. coli sensitive/resistant strains with an error of 5%. CONCLUSIONS: Bacteria can be classified in terms of their antibiotic susceptibility by using infrared spectroscopy and artificial neural networks.


Sujet(s)
Céfalotine/pharmacologie , Infections à Escherichia coli/traitement médicamenteux , Infections urinaires/traitement médicamenteux , Escherichia coli uropathogène/effets des médicaments et des substances chimiques , Résistance aux substances/génétique , Humains , , Spectrophotométrie IR , Infections urinaires/microbiologie , Escherichia coli uropathogène/classification , Escherichia coli uropathogène/isolement et purification
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