RESUMEN
New applications for medical biotextiles have been identified with the development of nanotechnological manufacturing technologies. Combination of nanotechnology and biotextile technology has resulted into a new field called bionanotextiles. Bionanotextiles are used in many areas which include wound dressings, bandages and tissue scaffolds. Silk fibroin (SF) from the cocoon of Bombyx mori, is one of the most favorable wound dressing materials due to its unique properties including biocompatibility, permeability, biodegradability, morphologic flexibility, and proper mechanical properties. The modification of antimicrobial properties of SFs can provide a barrier for bacterial penetration as wound dressing materials. In the present study, antibacterial polyethylenimine (PEI) (10, 20 and 30% (w/w)) was blended with SF and bionanotextiles were successfully fabricated by electrospinning. In addition, silk fibroin nanofibers were also functionalized with sulphate group in order to test whether they exhibit an antibacterial activity or not. Fibroin based bionanotextiles were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The cytotoxicity evaluations were carried out by L929 fibroblasts with MTT assay. The indirect cytotoxicity results demonstrate that all fibroin and PEI/fibroin extracts have no cytotoxicity on L929 cancer cell line. PEI/fibroin bionanotextiles showed strong antibacterial activities against gram positive Staphylococcus aureus and gram negative Pseudomonas aeruginosa.
Asunto(s)
Antibacterianos/administración & dosificación , Vendajes , Fibroínas/administración & dosificación , Nanotecnología , Seda , Antibacterianos/farmacología , Materiales Biocompatibles , Rastreo Diferencial de Calorimetría , Fibroínas/farmacología , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Pseudomonas aeruginosa/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacosRESUMEN
Treatment of rheumatoid arthritis by intraarticular administration of anti-inflammatory drugs encapsulated in drug delivery systems, such as liposomes/niosomes and lipogelosomes/niogelosomes, prolongs the residence time of the drugs in the joint. It was therefore anticipated that liposome/niosome entrapment would enhance the efficacy of drugs in the inflammatory sides. Liposomes are good candidates for the local delivery of therapeutic agents, such as diclofenac sodium (DFNa), for intraarticular delivery. Drugs for parenteral delivery must be sterile, and radiation sterilization is a method recognized by pharmacopoeias to achieve sterility of drugs. However, irradiation might also affect the performance of drug delivery systems. One of the most critical points is irradiation dose, because certain undesirable chemical and physical changes may accompany with the treatment, especially with the traditionally applied dose of 25 kGy. The present study aims to determine the effects of gamma irradiation on DFNa-loaded liposomes/niosomes and lipogelosomes/niogelosomes for the treatment of rheumatoid arthritis.
RESUMEN
The use of gamma rays for the sterilization of pharmaceutical raw materials and dosage forms is an alternative method for sterilization. However, one of the major problems of the radiosterilization is the production of new radiolytic products during the irradiation process. Therefore, the principal problem in radiosterilization is to determine and to characterize these physical and chemical changes originating from high-energy radiation. Parenteral drug delivery systems were prepared and in vitro characterization, biodistribution and treatment studies were done in our previous studies. Drug delivery systems (liposomes, niosomes, lipogelosomes and niogelosomes) encapsulating diclofenac sodium (DFNa) were prepared for the treatment of rheumatoid arthritis (RA). This work complies information about the studies developed in order to find out if gamma radiation could be applied as a sterilization method to DFNa, and the raw materials as dimyristoyl phosphatidylcholine (DMPC), surfactant I [polyglyceryl-3-cethyl ether (SUR I)], dicethyl phosphate (DCP) and cholesterol (CHOL) that are used to prepare those systems. The raw materials were irradiated with different radiation doses (5, 10, 25 and 50 kGy) and physicochemical changes (organoleptic properties pH, UV and melting point), microbiological evaluation [sterility assurance level (SAL), sterility and pyrogen test] and electron spin resonance (ESR) characteristics were studied at normal (25 °C, 60% relative humidity) and accelerated (40 °C, 75% relative humidity) stability test conditions.
RESUMEN
In this study, as a continuation of our research for new (arylalkyl)imidazole anticonvulsant compounds, the design, synthesis and anticonvulsant/antimicrobial activity evaluation of a series of 2-acetylnaphthalene derivatives have been described. Molecular design of the compounds has been based on the modification of nafimidone [1-(2-naphthyl)-2-(imidazol-1-yl)ethanone], which is a representative of the (arylalkyl)imidazole anticonvulsant compounds as well as its active metabolite, nafimidone alcohol (3, 4). In general, these compounds were variously substituted at the alkyl chain between naphthalene and imidazole rings and subjected to some other modifications to evaluate additional structure-activity relationships. The anticonvulsant activity profile of those compounds was determined by maximal electroshock seizure (MES) and subcutaneous metrazol (scM) seizure tests, whereas their neurotoxicity was examined using rotarod test. All the ester derivatives of nafimidone alcohol (5a-h), which were designed as prodrugs, showed anticonvulsant activity against MES-induced seizure model. Four of the most active compounds were chosen for further anticonvulsant evaluations. Quantification of anticonvulsant protection was calculated via the ip route (ED(50) and TD(50)) for the most active candidate (5d). Observed protection in the MES model was 38.46mgkg(-1) and 123.83mgkg(-1) in mice and 20.44mgkg(-1), 56.36mgkg(-1) in rats, respectively. Most of the compounds with imidazole ring also showed antibacterial and/or antifungal activities to a certain extent in addition to their anticonvulsant activity.
Asunto(s)
Antiinfecciosos/síntesis química , Anticonvulsivantes/síntesis química , Naftalenos/química , Animales , Antiinfecciosos/química , Antiinfecciosos/uso terapéutico , Anticonvulsivantes/química , Anticonvulsivantes/uso terapéutico , Cristalografía por Rayos X , Imidazoles/química , Conformación Molecular , Nafazolina/análogos & derivados , Nafazolina/química , Naftalenos/síntesis química , Naftalenos/uso terapéutico , Ratas , Convulsiones/inducido químicamente , Convulsiones/tratamiento farmacológico , Relación Estructura-ActividadRESUMEN
AIM: The aim of this study was to evaluate the antibacterial effects of different one-step and two-step self-etching primer/adhesives on Streptococcus mutans (S. mutans), Lactobacillus casei (L. casei), and Lactobacillus acidophilus (L. acidophilus). METHODS AND MATERIALS: The antibacterial effects of Clearfil Protect Bond Primer and Bonding agent; AdheSE Primer and Bonding agent; Adper Prompt L-Pop; Futurabond NR; Clearfil Tri S Bond; and Cervitec (positive control, 1% chlorhexidine varnish) were tested against standard strains of S. mutans, L. Casei, and L. acidophilus using the disk diffusion method. Standard filter paper disks (n=5) impregnated with 20 microL of each material were prepared. After incubation at 37 masculineC for 48 hours in a 5-10% CO2 atmosphere, the diameter of inhibition zones were measured in millimeters. Data were analyzed using one way analysis of variance (ANOVA) and multivariate analysis of variance (MANOVA). Duncan's Multiple Range Test was used for pairwise comparison. RESULTS: The size of inhibition zones produced by primer/adhesives varied among the brands. AdheSE Primer: S. mutans (20.6+/-1.51); L. casei (14.8+/-1.78); L. acidophilus (11.4+/-0.54). Adper Prompt L-Pop: S. mutans (19.6+/-1.51); L. casei (13.8+/-1.64); L. acidophilus (13.8+/-1.09). Cervitec: S. mutans (23+/-0.00); L. casei (27+/-0.70); L. acidophilus (22.4+/-0.54). Clearfil Protect Bond Primer: S. mutans (17+/-0.00); L. casei (17.6+/-0.54); L. acidophilus (22.4+/-0.54). Futurabond NR was found effective only against S. mutans (14.6+/-1.67). Of all the materials tested, AdheSE Bonding agent, Clearfil Protect Bond Bonding agent, and Clearfil Tri S Bond exhibited no inhibition zone (-) for all bacteria tested. CONCLUSION: Among the adhesives tested Clearafil Protect Bond Primer based upon monomer methacryloyloxydodecylpyridiniium bromide (MDPB) was found to be the most potent material against L. acidophilus and L. casei. AdheSE Primer and Adper Prompt L-Pop are highly effective against S. mutans. CLINICAL SIGNIFICANCE: Compared with other adhesive systems, Clearfil Protect Bond Primer (containing MDPB) showed a high antibacterial effect against all microorganizms tested. Two-step, self-etching primer/adhesive system Clearfil Protect Bond might be a suitable choice under minimally invasive restorations. The recently developed one-step, self-etching system Clearfil Tri S Bond showed no antibacterial effect against microorgazims tested.
Asunto(s)
Adhesivos/farmacología , Recubrimientos Dentinarios/farmacología , Lactobacillus/efectos de los fármacos , Cementos de Resina/farmacología , Streptococcus mutans/efectos de los fármacos , Grabado Ácido Dental/métodos , Pruebas Antimicrobianas de Difusión por Disco , Pruebas de Sensibilidad MicrobianaRESUMEN
Acetic acid hydrazide containing 5-methyl-2-benzoxazolinone (4) was synthesized by the condensation of 2-(5-methyl-2-benzoxazolinone-3-yl)acetate with hydrazine hydrate. Thiosemicarbazide derivatives (5a-5d) were afforded by the reaction of corresponding compound 4 with substituted isothiocyanates. The cyclization of compounds 5a-5d in the presence of triethylamine resulted in the formation of compounds 6a-6d containing 1,2,4-triazole ring. On the other hand, the treatment of compounds 5a-5d with orthophosphoric acid caused the conversion of side chain of compounds 5a-5d into 1,3,4-thiadiazole ring: thus, compounds 7a-7c were obtained. The treatment of compound 4 with aromatic aldehydes resulted in the formation of arylidene hydrazides as cis-trans conformers (8a-8e). The structures of the compounds were elucidated by spectral and elemental analysis. While most compounds were exhibiting high activity in the analgesic-anti-inflammatory field, most of them were found to be inactive against bacteria and fungi.
Asunto(s)
Antibacterianos/química , Benzoxazoles/química , Hidrazonas/síntesis química , Hidrazonas/farmacología , Semicarbacidas/síntesis química , Tiadiazoles/síntesis química , Triazoles/síntesis química , Analgésicos/síntesis química , Analgésicos/química , Analgésicos/farmacología , Animales , Antibacterianos/síntesis química , Antibacterianos/farmacología , Antiinflamatorios/síntesis química , Antiinflamatorios/química , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Cristalografía por Rayos X , Edema/tratamiento farmacológico , Edema/patología , Miembro Posterior/efectos de los fármacos , Hidrazonas/química , Hidrazonas/uso terapéutico , Metilación , Ratones , Viabilidad Microbiana/efectos de los fármacos , Modelos Moleculares , Estructura Molecular , Semicarbacidas/química , Semicarbacidas/farmacología , Semicarbacidas/uso terapéutico , Relación Estructura-Actividad , Tiadiazoles/química , Tiadiazoles/farmacología , Tiadiazoles/uso terapéutico , Triazoles/química , Triazoles/farmacología , Triazoles/uso terapéuticoRESUMEN
The aim of this study is to determine the effective concentrations of chlorhexidine on the release for prolonged periods of time from a novel hydrogel system. A hydrogel that exhibits a volume phase transition in response to temperature was synthesized by radiation copolymerization of ethylene glycol vinyl ether and butyl vinyl ether in the presence of crosslinking agent, diethylene glycol divinyl ether. Hydrogel samples in the disc form (diameter, 10 mm and height, 1.5 mm) were utilized as a matrix for the release of an antimicrobial agent, chlorhexidine diacetate. Chlorhexidine loading into the hydrogel was performed by water sorption at 4 degrees C, which allows high swelling and thus high loading capacity, i.e., approximately 36 mg drug per gram of dry gel. Chlorhexidine release was examined as short-term (24 h) and long-term (27 days) by UV spectrophotometer. Microbial studies were carried out by micro-dilution method in order to determine the effectiveness of the drug release. Minimum inhibitory concentration values for the pathogens of Streptococcus mutans and Lactobacillus casei were determined. The long-term chlorhexidine release is initially very fast. After that, the drug release reaches a slow but a steady rate. Such a release pattern provides an effective drug release. The prolonged release of chlorhexidine is continued up to the 27th day. MIC values for the two pathogens have been shown that the release rate from disc is effective to inhibit the growth of pathogens. These in vitro drug release results suggested that the thermosensitive hydrogel system developed in this study can be evaluated as a delivery system for the release of chlorhexidine.
Asunto(s)
Antiinfecciosos Locales/administración & dosificación , Clorhexidina/administración & dosificación , Hidrogeles/química , Compuestos de Vinilo/química , Preparaciones de Acción Retardada/química , Éteres/química , Calor , Humanos , Lacticaseibacillus casei/efectos de los fármacos , Streptococcus mutans/efectos de los fármacosRESUMEN
In this study, oxime and oxime ether derivatives of [1-(2-naphthyl)-2-(1,2,4-triazol-1-yl)ethanone] were prepared as potential anticonvulsant and antimicrobial compounds. The oxime was synthesized by the reaction of ketone and hydroxylamine hydrochloride. O-Alkylation of the oxime by various alkyl halides gave the oxime ether derivatives. Anticonvulsant activity of the compounds was determined by maximal electroshock and subcutaneous metrazole tests in mice and rats according to procedures of the Anticonvulsant Screening Program of National Institutes of Health. Neurotoxicity was determined by the rotorod test in mice and the positional sense test, gait and stance test in rats. In addition to anticonvulsant tests, all compounds were also evaluated against the following microorganisms: S. aureus, E. coli, P. aeruginosa, E. faecalis, C. albicans, C. parapsilosis, and C. krusei using microdilution broth method for possible antibacterial and antifungal activities. Although most of the O-alkyl substituted oxime ethers exhibited both anticonvulsant and antimicrobial activities, the O-arylalkyl substituted compounds were found to be inactive in both screening paradigms.
Asunto(s)
Antibacterianos/farmacología , Anticonvulsivantes/farmacología , Antifúngicos/farmacología , Naftalenos/farmacología , Oximas/farmacología , Triazoles/farmacología , Animales , Antibacterianos/síntesis química , Anticonvulsivantes/síntesis química , Antifúngicos/síntesis química , Candida albicans/efectos de los fármacos , Candida albicans/crecimiento & desarrollo , Cristalografía por Rayos X , Evaluación Preclínica de Medicamentos/métodos , Inyecciones Intraperitoneales , Ratones , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Naftalenos/síntesis química , Oximas/síntesis química , Ratas , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Triazoles/síntesis químicaRESUMEN
In this study, the synthesis of a novel series of Mannich bases of 5-mercapto-3-aryl-1,2,4-triazoles is described. The structures attributed to compounds la-5e were elucidated using IR and 1H-NMR spectroscopic techniques besides elemental analysis. The formation of 1-aminomethyl-3-substituted-1,2,4-triazole-5-thiones - not the isomeric 3-substituted-4-aminomethyl-1,2,4-triazole-5-thiones was unambiguously confirmed by X-ray crystallographic analysis of 1c. The compounds were examined for their in vivo anti-inflammatory and analgesic activity in two different bioassays, namely carrageenan-induced hind paw edema and p-benzoquinone-induced abdominal constriction tests in mice, respectively. In addition, the ulcerogenic effects of the compounds were determined. Among the tested derivatives most promising results were obtained for the compounds bearing a nonsubstituted phenyl group at C-3 position of the triazole ring (1a-e). The compounds were also evaluated for their in vitro antimicrobial activity against a series of gram positive bacteria [Staphylococcus aureus (ATCC 29213), Enterococcus faecalis (ATCC 29212)], gram negative bacteria [Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853)] and yeast-like microorganisms [Candida albicans (ATCC 90028), C. krusei (ATCC 6258), C. parapsilosis (ATCC 22019)]. One series of the examined compounds (3a-e) exhibited better antibacterial activity especially against gram positive bacteria than against gram negative bacteria. Compounds 2c, 3b, and 3e were found to be more effective against C. parapsilosis compared with the other derivatives (MIC: 16 microg/mL).
Asunto(s)
Analgésicos/síntesis química , Analgésicos/farmacología , Antiinfecciosos/síntesis química , Antiinfecciosos/farmacología , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/farmacología , Tionas/síntesis química , Tionas/farmacología , Triazoles/síntesis química , Triazoles/farmacología , Animales , Antifúngicos/síntesis química , Antifúngicos/farmacología , Bioensayo , Carragenina , Edema/inducido químicamente , Edema/prevención & control , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Masculino , Ratones , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Espectrofotometría Infrarroja , Úlcera Gástrica/inducido químicamente , Úlcera Gástrica/prevención & controlRESUMEN
OBJECTIVES: The aim of this in vitro study was to investigate the antibacterial activities of different generation dentin-bonding systems. METHOD AND MATERIALS: The antibacterial activities of dentin-bonding systems Optibond FL Primer, Single Bond, Clearfil SE Bond Primer, and Prompt-L-Pop were evaluated against Streptococcus mutans, Streptococcus salivarius, Lactobacillus casei, and Lactobacillus acidophilus. Cervitec (1% chlorhexidine varnish) was also examined as a positive control material. Disk diffusion tests with filter paper disks (n = 10) containing a drop of each material (20 microL) were used. After incubation at 37 degrees C for 48 hours, the growth inhibition zones were measured in millimeters. RESULTS: Of all the materials tested, Optibond FL Primer, Clearfil SE Bond Primer, and Prompt-LPop showed larger growth inhibition zones than the control material for all bacterial strains. No antibacterial effect was noted for Single Bond. The results indicated that Optibond FL Primer had the strongest effect against the S mutans and L casei, and Clearfil SE Bond Primer produced the largest inhibition zone for S salivarius and L acidophilus among the test materials. CONCLUSION: The antibacterial effects observed for the tested different generation dentin-bonding systems may be related to the acidic nature of the materials.
Asunto(s)
Antiinfecciosos Locales/farmacología , Recubrimientos Dentinarios/farmacología , Lacticaseibacillus casei/efectos de los fármacos , Lactobacillus acidophilus/efectos de los fármacos , Streptococcus mutans/efectos de los fármacos , Análisis de Varianza , Bisfenol A Glicidil Metacrilato/farmacología , Clorhexidina/farmacología , Combinación de Medicamentos , Cementos de Resina/farmacología , Estadísticas no Paramétricas , Streptococcus/efectos de los fármacos , Timol/farmacologíaRESUMEN
In this study, thirteen 3-hydroxy-6-methyl-2-substituted 4H-pyran-4-one derivatives were synthesized for the evaluation of their potential anticonvulsant activity. Mannich bases were prepared by the reaction of substituted piperazine derivatives with allomaltol and formaline. The structures of the synthesized compounds were confirmed by IR, (1)H-NMR and elemental analysis. Their anticonvulsant activities were determined in vivo by maximal electroshock (MES), sub-cutaneous Metrazol (scMet), and rotorod toxicity tests for neurological deficits. The antimicrobial activities of the synthesized compounds were investigated in vitro against some bacteria and fungi using the microdilution broth method. Ac-cording to the activity studies, 3-hydroxy-6-methyl-2-[4-(2-trifluoromethyl-phenyl)-piperazin-1-ylmethyl]-4H-pyran-4-one (3i) was the compound determined to be most active in the scMet test for all doses at four hours and for the 300 mg/kg dose at half an hour. 2-[4-(4-Chloro-phenyl)-piperazin-1-ylmethyl]-3-hydroxy-6-methyl-4H-pyran-4-one (3f) was found to be protective against MES whereas 2-chlorophenyl derivative (3e) was not. Looking at the antifungal activity results, compounds 3b, 3h, and 3i were determined to have activity against all fungi.
Asunto(s)
Anticonvulsivantes/síntesis química , Antifúngicos/química , Piranos/síntesis química , Animales , Anticonvulsivantes/química , Anticonvulsivantes/farmacología , Antifúngicos/síntesis química , Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Electrochoque , Masculino , Bases de Mannich/química , Ratones , Pruebas de Sensibilidad Microbiana , Pentilenotetrazol , Piranos/química , Piranos/farmacología , Convulsiones/inducido químicamente , Convulsiones/tratamiento farmacológicoRESUMEN
Streptococcus pneumoniae isolates resistant to penicillin and other antibiotics have been increasing in many parts of the world. The aim of this study was to evaluate the antimicrobial susceptibilities to penicillin and other commonly used agents in 98 isolates recovered between 1997 and 1998 from clinical specimens from children, and to determine the serotypes/serogroups related to resistance. Susceptibility to penicillin was determined by E-test and disk diffusion tests were used for the other antimicrobials. Serotyping was performed on all the isolates by the quelling reaction. The rates of intermediate- and high-level resistance to penicillin were 29.6% and 2%, respectively. Overall resistance to trimethoprim-sulfamethoxazole was high (46%), of which 21% coexisted with penicillin resistance. Resistance rates to erythromycin and chloramphenicol were 5% and 1%, respectively. Five isolates were multi-drug resistant. The most frequent serotypes associated with penicillin resistance were serotypes 19, 23, 6, 9 and 15.
Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Streptococcus pneumoniae/efectos de los fármacos , Niño , Hospitales Pediátricos , Hospitales Universitarios , Humanos , Resistencia a las Penicilinas , Serotipificación , Streptococcus pneumoniae/clasificación , TurquíaRESUMEN
The effect of widely used antiseptics and disinfectants on some hospital isolates of gram-negative bacteria was assessed by the quantitative suspension test Chlorhexidine gluconate (4%), savlon (1:100), and 5.25% sodium hypochlorite were tested. Savlon and chlorhexidine gluconate were effective at in-use concentrations and sodium hypochlorite was effective at 1:50 dilution.
Asunto(s)
Antiinfecciosos Locales/farmacología , Compuestos de Cetrimonio/farmacología , Clorhexidina/análogos & derivados , Clorhexidina/farmacología , Desinfectantes/farmacología , Bacterias Gramnegativas/patogenicidad , Hipoclorito de Sodio/farmacología , Infección Hospitalaria/prevención & control , Combinación de Medicamentos , Bacterias Gramnegativas/aislamiento & purificación , Desinfección de las Manos , Humanos , Pruebas de Sensibilidad MicrobianaRESUMEN
In this study, 16 new 6-difluorobenzoyl-3-piperazinomethyl-2-benzoxazolinones were synthesized by Mannich reaction. Their chemical structures were proven by IR, 1H-NMR and elemental analysis. The compounds were screened for their analgesic and anti-inflammatory activities. A modified Koster test, using acetylsalicylic acid (ASA, CAS 50-78-2) as the reference drug, was used to assess analgesic activity. The anti-inflammatory activity was evaluated by the carrageenan induced hind-paw oedema test. The analgesic activities of all compounds were higher than their anti-inflammatory activities and therefore the prominent analgesic actions of the compounds are thought to be due to a central effect. The microbiological effects of the compounds were evaluated in vitro against various pathogenic fungi and bacteria using the microdilution method. Most of the compounds were found to be inactive against bacteria and fungi. One of the compounds (31) possessed considerable analgesic activity as well as moderate antibacterial activity against S. aureus. Another compound (3m) showed analgesic and antifungal activities comparable to those of ASA and fluconazole (CAS 86386-73-4), respectively.
Asunto(s)
Analgésicos no Narcóticos/síntesis química , Analgésicos no Narcóticos/farmacología , Antiinfecciosos/síntesis química , Antiinfecciosos/farmacología , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/farmacología , Benzoxazoles/síntesis química , Piperazinas/síntesis química , Animales , Antibacterianos , Bacterias/efectos de los fármacos , Benzoxazoles/farmacología , Carragenina , Edema/inducido químicamente , Edema/prevención & control , Femenino , Hongos/efectos de los fármacos , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Ratones , Pruebas de Sensibilidad Microbiana , Dimensión del Dolor/efectos de los fármacos , Piperazinas/farmacología , Espectrofotometría InfrarrojaRESUMEN
PURPOSE: The aim of this work was to develop and characterize a highly loaded nanoparticulate system based on amphiphilic beta-cyclodextrins (CDs) to facilitate the parenteral administration of poorly soluble antifungal model drugs bifonazole and clotrimazole. METHODS: Inclusion complexes were characterized with spectroscopic techniques. Particle size distribution of nanospheres were determined by photon correlation spectroscopy (PCS). Nanospheres were assessed for hemolytic activity. Entrapped and released drug quantities were determined and minimum inhibitory concentration (MIC) values of drugs, amphiphilic beta-CDs, and drug loaded nanospheres were evaluated. RESULTS: 1:1 inclusion complexes of model drugs with amphiphilic beta-CDs gave nanospheres <300 nm (polydispersity index < 0.15) by nanoprecipitation technique without using surfactants. By direct preparation from preformed inclusion complexes, loading was increased 2- to 8-fold depending on CD type and loading technique. Conventionally loaded CD nanospheres displayed immediate release whereas preloaded and highly loaded nanospheres liberated model drugs over a period of 1 h reducing the initial burst effect. MIC values of bifonazole and clotrimazole were lowered significantly when associated to amphiphilic beta-CD nanospheres. CONCLUSION: Amphiphilic beta-CDs form nonsurfactant, highly loaded nanospheres with lower hemolytic activity than that of natural CDs directly from inclusion complexes. They enhanced solubility and subsequently therapeutic efficacy of the model drugs.
Asunto(s)
Ciclodextrinas/química , Nanotecnología/métodos , Tensoactivos/química , beta-Ciclodextrinas , Antifúngicos/química , Antifúngicos/farmacocinética , Química Farmacéutica , Ciclodextrinas/farmacocinética , Humanos , Pruebas de Sensibilidad Microbiana/estadística & datos numéricos , Microesferas , Estadísticas no Paramétricas , Tensoactivos/farmacocinéticaRESUMEN
In this study, some new Schiff bases were synthesized as antimicrobial agents using benzaldehyde derivatives and 1- or 2-aminoadamantane. The structures of the synthesized compounds were confirmed by IR, 1H-NMR and elementary analysis. Antimicrobial activities of the synthesized compounds were tested against some bacteria and yeast-like fungi. The antimicrobial activity of the compounds was investigated by broth microdilution method using two Gram positive (Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 29212) and two Gram negative (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853) bacteria and yeast-like fungi (Candida albicans ATCC 90028, Candida krusei ATCC 6258, Candida parapsilosis ATCC 22019). The antifungal activity of 1-((2-chloro-3,4-dimethoxybenzylidene) amino(adamantane (compound 3) against C. krusei and C. parapsilosis (minimal inhibitory concentration 32 micrograms/ml) was higher than that of the other tested compounds.
Asunto(s)
Adamantano/síntesis química , Antiinfecciosos/síntesis química , Bacterias/efectos de los fármacos , Hongos/efectos de los fármacos , Adamantano/farmacología , Antibacterianos , Antiinfecciosos/farmacología , Candida/efectos de los fármacos , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Espectrofotometría Infrarroja , Espectroscopía Infrarroja por Transformada de Fourier , Relación Estructura-ActividadRESUMEN
A number of 3-(4-substituted benzoylmethyl)-2-benzoxazolinones have been synthesized by reacting with 2-benzoxazolinone and 4-substituted phenacyl bromide in ethanol. Their chemical structures were confirmed by IR, 1H NMR and elemental analysis. For screening antimicrobial activity, minimum inhibitory concentration (MIC) values were determined against two Gram positive, one Gram negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus) and three yeast-like the fungi (Candida albicans, Candida krusei, Candida parapsilosis).
Asunto(s)
Antiinfecciosos/química , Benzoxazoles/química , Candida/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Antibacterianos , Antiinfecciosos/farmacología , Benzoxazoles/farmacología , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Estructura MolecularRESUMEN
Six new 5-(1-/2-naphthyloxymethyl)-1,3,4-oxadiazole-2(3H)-thione, 2-amino-5-(1-/2-naphthyloxymethyl)-1,3,4-oxadiazole, 5-(1-/2-naphthyloxymethyl)-1,3,4-oxadiazole-2(3H)-one derivatives have been synthesized from 1-and/or 2-naphthol. The structures of the compounds were confirmed by IR and 1H NMR spectral data and microanalysis. The antimicrobial properties of the compounds were investigated against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa, Candida albicans, C. krusei and C. parapsilosis using microbroth dilution method. 2-Amino-5-(2-naphthyloxymethyl)-1,3,4-oxadiazole and 5-(2-naphthyloxymethyl)-1,3,4-oxadiazole-2(3H)-one show significantly (32 microg/ml), compounds 5-(1-/2-naphthyloxymethyl)-1,3,4-oxadiazole-2(3H)-thione, 2-amino-5-(1-naphthyloxymethyl)-1,3,4-oxadiazole and 5-(1-naphthyloxymethyl)-1,3,4-oxadiazole-2(3H)-one moderately (64 microg/ml) active against C. krusei. All the compounds were active against S. aureus, E. coli, P. aeruginosa, C. albicans, and C. parapsilosis at 64-256 microg/ml concentration.
Asunto(s)
Antiinfecciosos/química , Candida/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Oxadiazoles/química , Pseudomonas aeruginosa/efectos de los fármacos , Antibacterianos , Antiinfecciosos/farmacología , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Oxadiazoles/farmacologíaRESUMEN
The in vitro activities of several antimicrobial agents against clinical isolates of Streptococcus pneumoniae (283), Haemophilus influenzae (272), Moraxella catarrhalis (179) and Streptococcus pyogenes (256) were determined in a multicentre study with the participation of five hospitals from four cities in Turkey. Penicillin resistance in S. pneumoniae was evaluated using the E-test and the remaining agents by disk diffusion. For S. pneumoniae overall 25.8% of the isolates were intermediately and 3.9% were highly resistant to penicillin and resistance to chloramphenicol, azithromycin and trimethoprim/sulphamethoxazole (TMP/SMX) was 3.8, 2.1 and 55.4%, respectively. Seven percent of H. influenzae produced beta-lactamase and all were susceptible to cefotaxime and azithromycin; the highest rate of resistance, 23.5%, was for TMP/SMX. Eighty-one percent of M. catarrhalis isolates produced beta-lactamase, 18.4% were resistant to TMP/SMX and all were susceptible to sulbactam/ampicillin combination. Resistance to chloramphenicol and azithromycin of S. pyogenes was 2.2 and 1.9%, respectively.