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1.
Arch Biochem Biophys ; 755: 109955, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38460659

RESUMEN

In this study, eighteen new ligands (B1-B18) containing a thiosemicarbazide core were synthesized and characterized in terms of physicochemical properties, molecular docking and in vitro biological activity. The structures of eleven ligands were investigated using X-Ray diffraction and Hirschfeld Surface analysis. To study the structure-activity relationship, the organic ligands contained pyridin-2-ylmethyl, pyridin-3-ylmethyl or pyridin-4-ylmethyl moieties and various substituents. Their pharmakokinetic profiles and molecular docking results suggest high potential as new drug candidates. The complexing ability of the selected organic ligands was also evaluated, yielding five new Cu(II) complexes (Cu(B1)Cl2, Cu(B4)Cl2, Cu(B10)Cl2, Cu(B17)Cl2, Cu(B18)Cl2). The obtained results suggest the formation of the polymeric structures. All organic ligands and Cu(II) complexes were tested for anticancer activity against prostate and melanoma cancer cells (PC-3, DU-145, LNCaP, A375, G-361, SK-MEL-28) and normal fibroblasts (BJ), as well as antimicrobial activity against six selected bateria strains. Among B1-B18 compounds, B3, B5, B9, B10, B12 and B14 exhibited cytotoxic activity. The studied Cu(II) complexes were in general more active, with Cu(B1)Cl2 exhibiting antincancer activity agains all three prostate cancer cells and Cu(B10)Cl2 reaching the IC50 value equal to 88 µM against G-361 melanoma cells. Several compounds also exhibited antimicrobial activity against gram-positive and gram-negative bacteria. It was found that the type of specific substituents, especially the presence of -chloro and -dichloro substituents had a greated impact on the cytotoxicity than the position of the nitrogen atom in the pyridylacetyl moiety.

2.
Molecules ; 29(9)2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38731510

RESUMEN

The scientific article focuses on the role of azulene and its derivatives in the therapy of dermatological diseases, presenting the latest laboratory and clinical research as well as prospects for further studies. In a synthetic literature review, various databases such as PubMed, Scopus, Web of Science, and the Database of Polish Scientific Journals were queried to select relevant articles concerning azulene. The conclusions drawn from the thematic analysis of the studies emphasize the multifaceted pharmacological actions of azulene and its derivatives including their anti-inflammatory properties, potential anticancer effects, photoprotective abilities, alleviation of itching, management of atopic dermatitis, and treatment of erectile dysfunction. However, there are certain limitations associated with the application of unmodified azulene on the skin, particularly related to photodecomposition and the generation of reactive oxygen species under UV radiation. These effects, in turn, necessitate further research on the safety of azulene and azulene-derived substances, especially regarding their long-term use and potential application in phototherapy. The authors of this work emphasize the necessity of conducting further preclinical and clinical studies to fully understand the mechanisms of action. Incorporating azulene and its derivatives into the therapy of dermatological disorders may represent an innovative approach, thereby opening new treatment avenues for patients.


Asunto(s)
Antineoplásicos , Azulenos , Enfermedades de la Piel , Azulenos/química , Azulenos/uso terapéutico , Humanos , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Antineoplásicos/farmacología , Enfermedades de la Piel/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Animales
3.
Molecules ; 28(16)2023 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-37630401

RESUMEN

Dermatological diseases pose a significant burden on the quality of life of individuals and can be challenging to treat effectively. In this aspect, cannabinoids are gaining increasing importance due to their therapeutic potential in various disease entities including skin diseases. In this synthetic review, we comprehensively analyzed the existing literature in the field of potential dermatological applications of a lesser-known subgroup of cannabinoids, the so-called minor cannabinoids, such as cannabidivarin (CBDV), cannabidiforol (CBDP), cannabichromene (CBC), tetrahydrocannabivarin (THCV), cannabigerolic acid (CBGA), cannabigerol (CBG), cannabielsoin (CBE), cannabimovone (CBM) or cannabinol (CBN), while drawing attention to their unique pharmacological properties. We systematically searched the available databases for relevant studies and analyzed the data to provide an overview of current thematic knowledge. We looked through the full-text, bibliographic and factographic databases, especially Scopus, Web of Science, PubMed, Polish Scientific Journals Database, and selected the most relevant papers. Our review highlights that minor cannabinoids exhibit diverse pharmacological activities, including anti-inflammatory, analgesic, antimicrobial, and anti-itch properties. Several studies have reported their efficacy in mitigating symptoms associated with dermatological diseases such as psoriasis, eczema, acne, and pruritus. Furthermore, minor cannabinoids have shown potential in regulating sebum production, a crucial factor in acne pathogenesis. The findings of this review suggest that minor cannabinoids hold therapeutic promise in the management of dermatological diseases. Further preclinical and clinical investigations are warranted to elucidate their mechanisms of action, determine optimal dosage regimens, and assess long-term safety profiles. Incorporating minor cannabinoids into dermatological therapies could potentially offer novel treatment options of patients and improve their overall well-being.


Asunto(s)
Acné Vulgar , Calidad de Vida , Humanos , Antiinflamatorios no Esteroideos , Cannabinol , Bases de Datos Factuales
4.
Bioorg Chem ; 123: 105765, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35427940

RESUMEN

The methods of fighting cancer are far from ideal, therefore it is necessary to search for innovative and effective drugs. In our work, we present pyrazole derivatives and their modifications with polymer microspheres as potential anticancer agents. Molecular and crystal structures of pyrazole derivatives were determined an X-ray analysis and characterized by theoretical calculations. Modifications of cross-linked polymer microspheres with pyrazole derivatives were made on the basis of divinylbenzene and glycidyl methacrylate. The in vitro antiproliferative activity of the pyrazole derivatives and their modified microspheres was assessed against a normal cell line, namely monkey epithelial renal cells (GMK) and cancer cell lines, such as human hepatocellular carcinoma cell line (HepG2), human breast adenocarcinoma cell line (MCF-7) as well as human lung adenocarcinoma cell line (A549), using the MTT assay. All the tested pyrazole derivatives and the polymer microspheres modified by them showed antiproliferative activity in vitro. Two of the modified substances showed the greatest ability to inhibit divisions of all cancer cells. In order to determine a potential target, molecular docking was performed. In silico studies carried out with the use of the human EphB1 receptor revealed that the analyzed compounds bound to the EphB1 binding site, and the compounds with the highest antiproliferative activity showed a better fit to the active site.


Asunto(s)
Antineoplásicos , Neoplasias , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Microesferas , Simulación del Acoplamiento Molecular , Estructura Molecular , Polímeros/farmacología , Pirazoles/química , Pirazoles/farmacología , Relación Estructura-Actividad
5.
Molecules ; 26(5)2021 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-33799954

RESUMEN

Bacterial strains become resistant to almost all classes of antibiotics, which makes it necessary to look for new substitutes. The non-absorbable ciprofloxacin-biguanide bismuth complex, used locally, may be a good alternative to a conventional therapy. The purpose of this study was to study the structure of the proposed ciprofloxacin (CIP) -bismuth(III)-chlorhexidine (CHX) composite (CIP-Bi-CHX). The spectroscopic techniques such as UV-VIS (ultraviolet-visible) spectroscopy, FTIR (Fourier-transform infrared) spectroscopy and NMR (Nuclear Magnetic Resonance) spectroscopy were used for structure characterization of the hybrid compound. The performed analysis confirmed the presence of the two active components-CIP and CHX and revealed the possible coordination sites of the ligands with bismuth ion in the metallo-organic structure. Spectroscopic study showed that the complexation between Bi(III) and CIP occurs through the carboxylate and ketone groups of the quinolone ring, while CHX combines with the central ion via the biguanide moieties.


Asunto(s)
Antibacterianos/química , Bismuto/química , Clorhexidina/química , Ciprofloxacina/química , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Espectroscopía de Resonancia Magnética/métodos , Estructura Molecular , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
6.
Molecules ; 25(21)2020 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-33153027

RESUMEN

The research was focused on developing a potentially antibacterial wound dressing made of polyurethane foam and loaded with bismuth-ciprofloxacin (Cip-Bi). The Cip-Bi chemical structure was confirmed by Fourier transform infrared spectroscopic (FTIR) analysis. The sought after antibacterial wound dressing was obtained by modification of the raw dressing with an iodine or bromine solution and subsequently with a Cip-Bi hydrogel. The amount of Cip-Bi loaded into the dressing matrix was determined indirectly on the basis of the differences in Cip-Bi concentrations, before and after the modification process, and the determination was performed with the HPLC (high-performance liquid chromatography) method. The modified dressing was found to have a two-step release of Cip-Bi, a feature helpful in the treatment of locally infected wounds and prevention of secondary bacterial infection. The zone of inhibition test against the selected Gram-positive and Gram-negative bacteria confirmed the antibacterial activity of the Cip-Bi-modified dressing. Preliminary tests conducted so far have been indicative of the Cip-Bi dressing's relatively high activity against the tested organisms.


Asunto(s)
Antibacterianos , Vendajes , Bismuto , Ciprofloxacina , Escherichia coli/crecimiento & desarrollo , Staphylococcus aureus/crecimiento & desarrollo , Antibacterianos/química , Antibacterianos/farmacología , Bismuto/química , Bismuto/farmacología , Ciprofloxacina/química , Ciprofloxacina/farmacología , Humanos , Pruebas de Sensibilidad Microbiana
7.
Ann Agric Environ Med ; 31(1): 94-99, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38549482

RESUMEN

INTRODUCTION AND OBJECTIVE: Photodynamic therapy (PDT) is a therapeutic option for low-risk basal cell carcinoma (BCC). The aim of the study was to assess the efficacy of topical PDT in the treatment of superficial BCC (sBCC) using two different photosensitizers: aminolevulinic acid hydrochloride (ALA-HCl) in a gel formulation with a lipid nanoemulsion (ALA-HCl in gel) and ALA methyl ester hydrochloride (MAL-HCl) in a cream formulation (MAL-HCl in cream). MATERIAL AND METHODS: 21 patients were treated twice with a one week interval between treatments. The formulations were applied onto lesions: 10 patients were treated with MAL-HCl in cream, and 11 with ALA-HCl in gel. After three hours of incubation and removing the preparations, fluorescence was assessed. The skin areas were then irradiated with red light 630 ± 5 nm. RESULTS: At the follow-up visit 12 weeks after the second treatment, complete clinical remission was found in 82% after ALA-HCl in gel and in 80% after MAL-HCl in cream. An excellent cosmetic result was found in 96% of patients after MALHCl in cream and in 100% after ALA-HCl in gel. Faster skin healing and less post-inflammatory hyperpigmentation during follow-up visits was observed after treatment with ALA-HCl in gel. CONCLUSIONS: Both formulations - ALA-HCl in gel and MAL-HCl in cream - were highly effective photosensitisers for PDT. The advantage of ALA-HCl in a gel formulation with a lipid nanoemulsion was faster skin healing, resulting in better cosmetic results.


Asunto(s)
Carcinoma Basocelular , Fotoquimioterapia , Neoplasias Cutáneas , Humanos , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/patología , Fotoquimioterapia/métodos , Resultado del Tratamiento , Carcinoma Basocelular/tratamiento farmacológico , Carcinoma Basocelular/etiología , Carcinoma Basocelular/patología , Ácido Aminolevulínico/uso terapéutico , Ácido Aminolevulínico/toxicidad , Respuesta Patológica Completa , Lípidos
8.
Pharmaceuticals (Basel) ; 16(12)2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38139832

RESUMEN

A series of N-Substituted 2-(benzenosulfonyl)-1-carbotioamide derivatives (WZ1-WZ4) were synthesized and characterized using spectral methods. A comprehensive activity study was performed for each compound. All compounds were tested for antibacterial activity. Moreover, in silico studies were carried out to determine the anticancer potential of the designed WZ1-WZ4 ligands. Based on molecular docking, aldehyde dehydrogenase was selected as a molecular target. The obtained data were compared with experimental data in vitro tests. Novel hybrids of the thiosemicarbazide scaffold and sulfonyl groups may have promising anticancer activity via the aldehyde dehydrogenase pathway. The best candidate for further studies appears to be WZ2, due to its superior selectivity in comparison to the other tested compounds.

9.
Pharmaceutics ; 14(2)2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35214078

RESUMEN

Photodynamic therapy (PDT) is safe and effective in the treatment of patients with actinic keratosis (AK). The aim of the study was to assess the efficacy, tolerability and cosmetic outcome of topical PDT in the treatment of AKs with three forms of photosensitizers: 5-Aminolevulinic acid hydrochloride (ALA-HCl), 5-Aminolevulinate methyl ester hydrochloride (MAL-HCl) and 5-Aminolevulinate phosphate (ALA-P). The formulations were applied onto selected scalp/face areas. Fluorescence was assessed with a FotoFinder Dermoscope 800 attachment. Skin areas were irradiated with Red Beam Pro+, Model APRO (MedLight GmbH, Herford, Germany). Applied treatments were assessed during the PDT as well as 7 days and 12 weeks after its completion. Ninety-four percent of patients rated obtained cosmetic effect excellent. The efficacy of applied PSs did not differ significantly. However, pain intensity during the PDT procedure was significantly lower in the area treated with ALA-P (5.8 on average) in comparison to the areas treated with ALA-HCl or MAL-HCl (7.0 on average on 0-10 scale). Obtained results show that ALA-P may undergo more selective accumulation than ALA-HCl and MAL-HCl. Our promising results suggest that PDT with the use of ALA-P in AK treatment may be an advantageous alternative to the already used ALA-HCl and MAL-HCl.

10.
J AOAC Int ; 93(3): 820-4, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20629382

RESUMEN

Two simple, accurate, and precise HPTLC methods have been established for the determination of mexiletine hydrochloride, an antiarrhythmic agent, in Mexicord capsules. Analyses were performed in horizontal chambers on RP C18F254s and normal-phase amino (NH2) HPTLC precoated plates with the mobile phases tetrahydrofuran-citrate buffer, pH 4.45 (3 + 7, v/v) and chloroform-tetrahydrofuran-hexane-ethylamine (3 + 2 + 5 + 0.1, v/v/v/v), respectively. The plates were developed for a distance of 40 mm in both cases. Densitometric measurements were achieved in the UV mode at 217 nm based on peak areas with semilinear calibration curves (R2 > or = 0.97) in the concentration range 0.5-8.0 microg/spot for the NH2 and C18 HPTLC methods. The elaborated chromatographic methods were validated in accordance with International Conference on Harmonization guidelines in terms of linearity, accuracy (99.64% for NH2 and 99.53% for C18), precision (intraday RSD 1.16 and 2.71%, respectively), sensitivity (LOD 0.1 microg/spot for both systems), and specificity.


Asunto(s)
Antiarrítmicos/análisis , Cromatografía en Capa Delgada/métodos , Mexiletine/análisis , Cápsulas , Densitometría
11.
Materials (Basel) ; 12(18)2019 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-31540255

RESUMEN

BACKGROUND: The purpose of the study was to demonstrate the usefulness of the Fourier transform infrared spectroscopy (FTIR) method for the evaluation of the modification process of biomaterials with the participation of active substances. METHODS: Modified catheter samples were prepared by activating the matrix with an acid, iodine, or bromine, and then immobilizing the active molecules. To carry out the modification process, the Fourier transform infrared-attenuated total reflectance (FTIR-ATR) method was used. RESULTS: FTIR analysis indicated the presence of the immobilized substances in the catheter matrix and site-specific reactions. CONCLUSION: We surmise that the infrared spectroscopic technique is an ideal tool for the assessment of the drug immobilization and the changes occurring in the course of the modification process.

12.
Int J Pharm ; 339(1-2): 39-46, 2007 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-17376617

RESUMEN

Strong covalent immobilization of amikacin on Uni-Graft((R)) DV straight vascular prostheses made of gelatine-sealed poly(ethylene terephthalate) fibres was performed according to procedure described in the Polish Patent No. P-358934. The concentrations of amikacin in sample solutions were estimated either by HPLC or by UV spectroscopy method previously optimized for amikacin measurements. A high correlation was found between these two methods. It was found that the antibiotic was bound in mixed-type way via three types of interactions: strong covalent bonds (dominating amount: 81.84%) and weak interactions: physical adsorption and ionic bonds (18.19%). Even when total amount of physically and ionically attached drug has been released, the remaining covalently bound amount still locally protected the prostheses in vitro against bacteria. The release test was conducted in PBS at pH 7.4 at 37 degrees C and showed that about 15% of total drug amount was eluted from the matrix during the first 7 days of shaking, then no more antibiotic was released. It suggested that about 85% of amikacin attached to prosthesis modified in mixed-type mode was bound via covalent interactions. A bacterial inhibition test on Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923 and Pseudomonas aeruginosa ATCC 27853 showed inhibition of growth for all strains at low inoculum concentrations up to 30 days as well as high inoculum concentration for E. coli. At high concentrations of S. aureus and P. aeruginosa, the modified prostheses showed slight bacteriostatic effect since 10th day of experiment. Amikacin-modified vascular prostheses might therefore be protected against bacterial infection locally, without long-lasting drug release to human system.


Asunto(s)
Amicacina/administración & dosificación , Antibacterianos/administración & dosificación , Infecciones Bacterianas/prevención & control , Prótesis Vascular , Portadores de Fármacos , Complicaciones Posoperatorias/prevención & control , Amicacina/química , Cromatografía Líquida de Alta Presión , Humanos , Pruebas de Sensibilidad Microbiana
13.
J AOAC Int ; 90(4): 977-86, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17760335

RESUMEN

A method using capillary zone electrophoresis was developed for the simultaneous separation of 14 antiarrhythmic drugs belonging to various classes. The drugs are separated on a fused-silica capillary, 90 cm x 75 microm (72 cm effective length), with phosphate and acetate buffers as background electrolytes and UV detection at 217 nm. The effects of buffer pH, temperature, and applied voltage on the migration of the drugs were studied. The pH was found to be the most significant factor determining effective separation. The antiarrhythmic compounds are completely separated within a relatively short time (< 7 min) by using 70 mM phosphate buffer at pH 7.91, an applied voltage of 28 kV, and a temperature of 32 degrees C. Mexiletine (MEX) and flecainide (FLE) were quantified under conditions of the optimum separation. The calibration graphs were constructed over the concentration range of 4.0-14.0 microg/mL for both drugs with good correlation (r > or = 0.9999). Detection and quantitation limits were found to be 0.5 and 1.5 microg/mL for FLE and 0.7 and 2.1 microg/mL for MEX, respectively. The proposed method was used for the determination of both drugs in their commercial forms with satisfactory precision (relative standard deviations of 0.36-1.21% for FLE and 0.78-1.66% for MEX) and accuracy (relative standard errors of 0.13-1.17% for FLE and 0.35-1.18% for MEX).


Asunto(s)
Antiarrítmicos/farmacología , Química Farmacéutica/métodos , Electroforesis Capilar/métodos , Flecainida/análisis , Mexiletine/análisis , Calibración , Diseño de Fármacos , Electrólitos , Flecainida/aislamiento & purificación , Concentración de Iones de Hidrógeno , Mexiletine/aislamiento & purificación , Fosfatos/química , Análisis de Regresión , Reproducibilidad de los Resultados , Espectrofotometría Ultravioleta , Temperatura
14.
Biomed Pharmacother ; 93: 1269-1276, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28747001

RESUMEN

A series of thiosemicarbazides with 4-nitrophenyl group was obtained in the reaction of carboxylic acid hydrazides with isothiocyanates. All compounds were checked for their antibacterial and antiproliferative activity. Our results have shown that derivatives 6-8 possessed antibacterial activity against S. aureus, S. epidermidis, S. mutans and S. sanguinis, moderate cytotoxicity and good therapeutic safety in vitro. Additionally, compounds 1 and 4 significantly inhibited A549, HepG2 and MCF-7 cell division. Moreover, PASS software indicated that newly obtained compounds are potential α-glucosidase inhibitors. This was confirmed by in vitro studies. To investigate the mode of interaction with the molecular target compounds were docked to glucose binding site of the enzyme and exhibited a similar binding mode as glucose.


Asunto(s)
Antibacterianos/farmacología , Proliferación Celular/efectos de los fármacos , Inhibidores de Glicósido Hidrolasas/farmacología , Nitrofenoles/farmacología , Semicarbacidas/farmacología , Células A549 , Bacterias/efectos de los fármacos , Sitios de Unión , Línea Celular , Células Hep G2 , Humanos , Células MCF-7 , Simulación del Acoplamiento Molecular , Relación Estructura-Actividad
15.
J AOAC Int ; 89(1): 71-7, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16512231

RESUMEN

Nifedipine (Nif) is widely used in treating cardiovascular disorders (especially hypertension) and for inhibiting preterm labor. A fully validated selective high-performance liquid chromatographic method with diode array detection, using solid-phase extraction, was developed for the determination of Nif in human serum. To assess specificity, Nif and its degradation products were separated on a Purospher RP-18 (5 microm, 125 x 4 mm) column plus a LiChrospher 100 RP-18 (5 microm, 4 x 4 mm) precolumn with a mobile phase of methanol-10 mM aqueous trifluoroacetic acid, pH 7.3 (57 + 43, v/v); chromatographic separation was followed by UV detection at 238 nm. For toxicological analysis, Nif in the presence of other calcium-channel antagonist drugs was identified under optimum chromatographic conditions. The calibration graph was constructed over the concentration range of 12.5-400 ng/mL in serum with good correlation (r = 0.9956). This method was not subject to interference by other plasma components and was successfully applied to the assay of Nif in spiked human serum and in serum of women in preterm labor after sublingual administration of 30 mg Nif per day divided into 3 equal doses. The mean recovery based on the ratio of the slopes of serum and mobile phase standard curves was 96.5%. The detection and quantification limits of the drug in spiked human serum were found to be 6 and 17.5 ng/mL, respectively. Validation of the method demonstrated good intraday and interday precision, which ranged from 2.18 to 6.67% and from 6.52 to 11.93%, respectively.


Asunto(s)
Técnicas de Química Analítica/métodos , Cromatografía Líquida de Alta Presión/métodos , Nifedipino/sangre , Calcio/química , Bloqueadores de los Canales de Calcio/química , Canales de Calcio/química , Calibración , Química Farmacéutica/métodos , Cromatografía , Femenino , Humanos , Concentración de Iones de Hidrógeno , Luz , Metanol/química , Modelos Estadísticos , Nicardipino/farmacología , Nifedipino/farmacología , Nimodipina/farmacología , Nitrendipino/farmacología , Trabajo de Parto Prematuro , Embarazo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Factores de Tiempo , Ácido Trifluoroacético/análisis , Rayos Ultravioleta
16.
Int J Pharm ; 288(1): 131-40, 2005 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-15607265

RESUMEN

Our aim was to develop a new method of chemical binding of gentamicin to vascular prostheses made of poly(ethylene terephthalate) (PET) fibres and covered with pig gelatine. We estimated (with the HPLC method) the immobilization yield, which equalled 76 or 8% depending on the concentration of the antibiotic used and the amount of gentamicin bound to the prosthesis (1.08-20.6 mg/g of prosthesis). The antibiotic was coupled in two modes: stable covalent binding or weak adhesion. The results confirmed that only a small quantity of the antibiotic (1.03-3.09%) was bound by adsorption. The modification of the prosthesis surface with immobilized gentamicin was visualized with a scanning microscope (SEM). Bacteriostatic properties of bound gentamicin were verified against different concentrations (cfu) of Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus strains. We have found lack of growth of these pathogen strains in Luria-Bertani (LB) medium containing pieces of gentamicin-coupled prosthesis during at least 28 days of the experiment. Contrary to that, a control medium containing pieces of prosthesis only soaked with gentamicin allowed a constant growth of bacteria.


Asunto(s)
Prótesis Vascular , Gelatina/química , Gentamicinas/química , Tereftalatos Polietilenos/química , Gelatina/farmacología , Gentamicinas/farmacología , Pruebas de Sensibilidad Microbiana , Tereftalatos Polietilenos/farmacología
17.
J AOAC Int ; 88(5): 1525-9, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16386004

RESUMEN

A high-performance thin-layer chromatography (TLC) method coupled with densitometric analysis has been developed for simultaneous measurement of trandolapril (TRA) and verapamil (VER) in 2-component mixtures and in their combination capsules. The active substances were extracted from capsules with methanol (mean recovery: 103.4% for TRA, 97.13% for VER) and chromatographed on TLC plates coated with silica gel 60 F254 in horizontal chambers with ethyl acetatc-ethanol-acetic acid (8 + 2 + 0.5, v/v) mobile phase. Chromatographic separation of these components was followed by ultraviolet densitometric quantification at 215 nm. The calibration graphs were constructed over the concentration range from 0.5 to 1.5 microg/microL (corresponding to 5.0-15.0 microg/spot) for both drugs with good correlation (r > or = 0.990). Detection and quantitation limits were found to be 1.25 and 3.75 microg/spot for TRA and 0.15 and 0.45 microg/spot for VER, respectively. The proposed method was used for determination of both drugs in TRA-VER capsules with satisfactory precision [0.97% < relative standard deviation (RSD) < 4.50% for TRA, 0.49% < RSD < 3.10% for VER] and accuracy [2.16% < relative error (RE) < 4.90% for TRA, 1.73% < RE < 5.68% for VER].


Asunto(s)
Cromatografía en Capa Delgada/métodos , Densitometría/métodos , Indoles/análisis , Verapamilo/análisis , Sesgo , Calibración , Cápsulas , Combinación de Medicamentos , Estándares de Referencia , Análisis de Regresión , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
18.
Mater Sci Eng C Mater Biol Appl ; 49: 274-280, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25686950

RESUMEN

The purpose of this study was to evaluate in vitro safety of the novel tosufloxacin (TOS)-treated catheters with the prolonged antimicrobial activity. The test samples of silicone latex catheter were prepared by the immobilization of TOS on chitosan (CHIT)-coated catheter by means of covalent bonds and non-covalent interactions. Each step of the modification process of catheter surface was observed using ATR-Fourier transform infrared spectroscopy. In vitro cytotoxicity of the modified and unmodified catheters was assessed by direct and indirect tests in accordance with ISO standards using green monkey kidney (GMK) cell line. The MTT, lactate dehydrogenase activity (LDH), WST-8, Sulforhodamine B (SRB) test results and microscopic observation clearly indicated that unmodified silicone latex catheters decrease cell metabolic activity, act as a cytotoxic agent causing cell lysis and induce cell death through necrotic or apoptotic process. We suggest that chitosan coat with TOS immobilized limits leaching of harmful agents from silicone latex material, which significantly enhances survivability of GMK cells and therefore is quite a good protection against the cytotoxic effect of this material.


Asunto(s)
Antiinfecciosos/química , Fluoroquinolonas/efectos adversos , Fluoroquinolonas/química , Naftiridinas/efectos adversos , Naftiridinas/química , Catéteres Urinarios/efectos adversos , Animales , Antiinfecciosos/efectos adversos , Apoptosis/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Línea Celular , Quitosano/química , Chlorocebus aethiops , Látex/química , Siliconas/química
19.
J AOAC Int ; 86(2): 229-35, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12723910

RESUMEN

Derivative UV-spectrophotometric and liquid chromatographic (LC) methods for fleroxacin determination were validated. In the spectrophotometric assay, first-, second-, third-, and fourth-order measurements were applied with the use of peak-zero and peak-peak techniques. The linear correlation between amplitude of the peak and concentration of the examined drug ranged from 2.0 to 12.0 micro/mL. An isocratic LC analysis was performed on a Purospher ODS column with an acidic mobile phase containing tetrabutylammonium hydroxide. Measurements were made at a wavelength of 285 nm with 4-aminobenzoic acid (PABA) as internal standard. The calibration curve was linear (r = 0.9999) in the studied range of concentration (1.0-10.0 microg/mL). The accuracy (mean recovery, about 100%), precision (relative standard deviation < 1%), selectivity, and sensitivity of the elaborated methods were satisfactory.


Asunto(s)
Antiinfecciosos/análisis , Fleroxacino/análisis , Ácido 4-Aminobenzoico , Cromatografía Liquida , Contaminación de Medicamentos , Indicadores y Reactivos , Metales , Estándares de Referencia , Reproducibilidad de los Resultados , Soluciones , Espectrofotometría Ultravioleta , Comprimidos
20.
J AOAC Int ; 87(4): 847-51, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15295878

RESUMEN

A new second-order-derivative spectrophotometric method using zero-crossing technique measures quinapril (QUI) and hydrochlorothiazide (HYD) in 2-component mixtures. The procedure does not require prior separation of components from the sample. QUI was determined at a wavelength of 211.6 nm (zero-crossing wavelength point of HYD). Similarly, HYD was measured at 270.8 nm (zero-crossing wavelength point of QUI ). Calibration graphs were constructed over the concentration range of 4.0 to 24.0 microg/mL for QUI and 2.5 to 15.0 microg/mL for HYD. Detection and quantitation limits were 0.85 and 2.5 microg/mL for QUI and 0.12 and 0.4 microg/mL for HYD, respectively. The accuracy (recovery 100.5-102%), precision (relative standard deviation less than 3.5% for QUI and 1.5% for HYD), selectivity, and sensitivity of the elaborated methods were satisfactory. The proposed method was applied successfully for the determination of both drugs in QUI-HYD tablets.


Asunto(s)
Antihipertensivos/análisis , Hidroclorotiazida/análisis , Tetrahidroisoquinolinas/análisis , Calibración , Combinación de Medicamentos , Estabilidad de Medicamentos , Metanol , Quinapril , Estándares de Referencia , Análisis de Regresión , Reproducibilidad de los Resultados , Solventes , Espectrofotometría Ultravioleta , Comprimidos
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