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1.
Int J Biol Macromol ; 150: 746-755, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32035962

RESUMO

New amphiphilic dextran esters were obtained by polysaccharide functionalization with different substituted 1,2,3-triazoles-4-carboxylic acid via in situ activation with N, N'-carbonyldiimidazole. Nitrogen-containing heterocyclic derivatives were achieved by copper(I)-catalyzed cycloaddition reaction between organic azides and ethyl propiolate. Structural characteristics of the compounds were studied by elemental analysis, Fourier transform infrared and nuclear magnetic resonance spectroscopy (1H and 13C-NMR). Thermogravimetric analysis, differential scanning calorimetry and wide-angle X-ray diffraction were used for esters characterization. Properties of polymeric self-associates, formed in aqueous solution, were studied by dynamic light scattering and transmission electron microscopy. The critical aggregation concentration values for dextran esters, determined by fluorescence spectroscopy, were in the range of 4.1-9.5 mg/dL. Antimicrobial activity, investigated for some of the polymers by disc-diffusion method, pointed out that polysaccharide esters were active.

2.
Carbohydr Polym ; 223: 115118, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31426975

RESUMO

New biocompatible amphiphilic block copolymers were prepared using two natural compounds as starting materials, a polysaccharide (dextran) and a bile acid (deoxycholic acid). The copolymers were synthesized by dipolar 1,3-cycloaddition reaction between dextran with azide end groups and deoxycholic acid - oligo(ethylene glycol)s polyester with propargyl end groups. Different copolymer composition were obtained by variation of molecular weights of dextran (Mn 4.5, 8, 15 kDa) and polyester (Mn 2-6 kDa), as well as the length of oligo(ethylene glycol) (2-4 ethylenglycol units) used for polyester synthesis. These copolymers can for micelle like aggregates in aqueous medium with nanometric size (50-600 nm) and spherical form, as assessed by light scattering, atomic force microscopy and transmission electron microscopy. Encapsulation of the hydrophobic drug curcumin in micelles could increase 68,181 times its water solubility, and curcumin release from micelles was slow and with reduced burst effect.


Assuntos
Antineoplásicos/química , Materiais Biocompatíveis/síntese química , Curcumina/química , Ácido Desoxicólico/química , Dextranos/química , Polímeros/síntese química , Tensoativos/síntese química , Materiais Biocompatíveis/química , Cápsulas/química , Liberação Controlada de Fármacos , Interações Hidrofóbicas e Hidrofílicas , Micelas , Conformação Molecular , Tamanho da Partícula , Polímeros/química , Solubilidade , Propriedades de Superfície , Tensoativos/química
3.
Medicina (Kaunas) ; 55(7)2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31269687

RESUMO

Background and objectives: The etiology of anemia associated with heart failure is not fully understood, but there are data suggesting the involvement of multiple mechanisms, including various drug therapies used in patients with heart failure. Our primary objective was to evaluate the impact of beta blockers, angiotensin-converting enzyme inhibitors, and calcium-channel blockers on iron metabolism in patients with heart failure. Materials and Methods: This was a prospective observational study that included patients diagnosed with heart failure and iron deficiency (defined by ferritin <100 µg/L, or 100-300 µg/L with transferrin saturation <20%). Patients with anemia secondary to a known cause were excluded. Results: We found a statistically significant correlation between beta-blocker treatment and ferritin values (p = 0.02). Iron, hemoglobin, and hematocrit levels were significantly lower in the patients using calcium-channel blockers than those who were not. We also found a statistically significant indirect correlation (p = 0.04) between the use of angiotensin-converting enzyme inhibitors and hematocrit levels. Conclusion: The contribution of our study arises from the additional data regarding the drug-induced etiology of iron deficiency. Practitioners should be aware of the potential impact of therapeutic recommendations and this should imply a close monitoring of the biochemical parameters of iron deficiency in this category of patients.


Assuntos
Anemia/etiologia , Insuficiência Cardíaca/tratamento farmacológico , Distúrbios do Metabolismo do Ferro/etiologia , Antagonistas Adrenérgicos beta/efeitos adversos , Antagonistas Adrenérgicos beta/uso terapêutico , Idoso , Anemia/sangue , Anemia/complicações , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Bloqueadores dos Canais de Cálcio/efeitos adversos , Bloqueadores dos Canais de Cálcio/uso terapêutico , Feminino , Insuficiência Cardíaca/sangue , Humanos , Ferro/análise , Ferro/sangue , Distúrbios do Metabolismo do Ferro/sangue , Masculino , Pessoa de Meia-Idade
4.
Materials (Basel) ; 12(4)2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30781782

RESUMO

In the past many research studies have focused on the thiazolidine-4-one scaffold, due to the important biological effects associated with its heterocycle. This scaffold is present in the structure of many synthetic compounds, which showed significant biological effects such as antimicrobial, antifungal, antioxidant, anti-inflammatory, analgesic, antidiabetic effects. It was also identified in natural compounds, such as actithiazic acid, isolated from Streptomyces strains. Starting from this scaffold new xanthine derivatives have been synthetized and evaluated for their antibacterial and antifungal effects. The antibacterial action was investigated against Gram positive (Staphyloccoccus aureus ATCC 25923, Sarcina lutea ATCC 9341) and Gram negative (Escherichia coli ATCC 25922) bacterial strains. The antifungal potential was investigated against Candida spp. (Candida albicans ATCC 10231, Candida glabrata ATCC MYA 2950, Candida parapsilosis ATCC 22019). In order to improve the antimicrobial activity, the most active xanthine derivatives with thiazolidine-4-one scaffold (XTDs: 6c, 6e, 6f, 6k) were included in a chitosan based polymeric matrix (CS). The developed polymeric systems (CS-XTDs) were characterized in terms of morphological (aspect, particle size), physic-chemical properties (swelling degree), antibacterial and antifungal activities, toxicity, and biological functions (bioactive compounds loading, entrapment efficiency). The presence of xanthine-thiazolidine-4-one derivatives into the chitosan matrix was confirmed using Fourier transform infrared (FT-IR) analysis. The size of developed polymeric systems, CS-XTDs, ranged between 614 µm and 855 µm, in a dry state. The XTDs were encapsulated into the chitosan matrix with very good loading efficiency, the highest entrapment efficiency being recorded for CS-6k, which ranged between 87.86 ± 1.25% and 93.91 ± 1.41%, depending of the concentration of 6k. The CS-XTDs systems showed an improved antimicrobial effect with respect to the corresponding XTDs. Good results were obtained for CS-6f, for which the effects on Staphylococcus aureus ATCC 25923 (21.2 ± 0.43 mm) and Sarcina lutea ATCC 9341 (25.1 ± 0.28 mm) were comparable with those of ciprofloxacin (25.1 ± 0.08 mm/25.0 ± 0.1 mm), which were used as the control. The CS-6f showed a notable antifungal effect, especially on Candida parapsilosis ATCC 22019 (18.4 ± 0.42 mm), the effect being comparable to those of nystatin (20.1 ± 0.09 mm), used as the control. Based on the obtained results these polymeric systems, consisting of thiazolidine-4-one derivatives loaded with chitosan microparticles, could have important applications in the food field as multifunctional (antimicrobial, antifungal, antioxidant) packaging materials.

5.
Pharm Res ; 34(10): 2185-2196, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28707165

RESUMO

PURPOSE: Aim of this work was preparation of bioadhesive gel formulations based on Hydroxypropyl methylcellulose (HPMC), Poly(acrylic acid) (PAA) or Sodium alginate (SA) loaded with anise/fluconazole ß-cyclodextrin inclusion complexes in 1:2 and 1:3 ratios intended for vaginal applications. METHODS: Freeze-drying method was effectively utilized and superporous morphology was obtained. The superporous morphology of the lyophilized gels, dynamic water vapor sorption measurements, drug release kinetics studies and their antimicrobial activities are presented. RESULTS: HPMC content influences especially the sorption/desorption behaviour of HPMC-based PAA gels and the morphology of the gel formulations with fluconazole/ß-cyclodextrin inclusion complexes, due to the interactions among the gel networks absorbing water molecules. It was found that fluconazole release kinetics correspond to quasi-Fickian, Fickian diffusion and non-Fickian mechanisms for the studied hydrogels. The tested vaginal formulations with ß-cyclodextrin inclusion complexes exhibited selectivity toward S. aureus ATCC 25923 and all tested Candida strains in comparison with the gel formulation without ß-cyclodextrin. CONCLUSIONS: The fluconazole/ß cyclodextrin inclusion complexes ensure a controlled release of fluconazole over a few days, the highest amount of drug release (92%) being observed after 43 h. These bioadhesive gel formulations could be very promising topical alternative for treatment of vaginal fungal infections.


Assuntos
Resinas Acrílicas/química , Alginatos/química , Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/química , Fluconazol/administração & dosagem , Fluconazol/química , Derivados da Hipromelose/química , Administração Intravaginal , Química Farmacêutica/métodos , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Feminino , Liofilização/métodos , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Humanos , Hidrogéis/química , Microscopia Eletrônica de Varredura , Reologia/métodos , Staphylococcus aureus , Absorção Vaginal , beta-Ciclodextrinas/química
6.
Carbohydr Polym ; 161: 181-186, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28189227

RESUMO

Cationic amphiphilic dextran derivatives with a long alkyl group attached to the reductive end of the polysaccharide chain and quaternary ammonium groups attached as pendent groups to the main dextran backbone were synthesized and tested for their antimicrobial properties against several bacteria and fungi strains. Dependence of antimicrobial activity on both polymer chemical composition (dextran molar mass, length of end alkyl group and chemical structure of ammonium groups) and type of microbes was highlighted by disc-diffusion method (diameter of inhibition zone) and broth microdilution method (minimum inhibitory concentrations). Polymers had antimicrobial activity for all strains studied, except for Pseudomonas aeruginosa ATCC 27853. The best activity against Staphylococcus aureus (Minimun Inhibitory Concentration 60µg/mL) was provided by polymers obtained from dextran with lower molecular mass (Mn=4500), C12H25 or C18H37 end groups, and N,N-dimethyl-N-benzylammonium pendent groups.


Assuntos
Bactérias/efeitos dos fármacos , Dextranos/farmacologia , Fungos/efeitos dos fármacos , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Dextranos/química , Testes de Sensibilidade Microbiana
7.
Basic Clin Pharmacol Toxicol ; 120(5): 498-504, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27883283

RESUMO

Acute poisonings represent a common cause of morbidity and mortality worldwide. The prognostic utility of the transthoracic echocardiography (TTE) parameters combined with brain natriuretic peptide (BNP) in acute poisoning with different xenobiotics, upon admission in the hospital, was not evaluated. This prospective observational cohort study included 229 acutely poisoned non-diabetic adults, with a median age of 44 years (range 18-90 years), 50.7% women, with an in-hospital mortality rate of 8.7%. Univariate logistic regression analysis showed that age, the left ventricle kinetic abnormalities, the E-wave deceleration time (EDT) and BNP correlated significantly with mortality in acutely poisoned patients. Multivariate logistic regression showed that only EDT [odds ratio (OR) 3.44, 95% confidence interval (CI) 1.54-7.69, p 0.003], BNP (OR 1.61, 95% CI: 1.02-2.55, p 0.04) and age (OR 2.66, 95% CI: 1.23-5.76, p 0.013) are predictive for mortality. The receiver-operating characteristic (ROC) analysis proved EDT [area under the ROC curve (AUC), 0.85; CI: 0.76-0.94; p 0.001], BNP (AUC, 0.83; CI: 0.75-0.91; p 0.001) and age (AUC, 0.82; CI: 0.74-0.90; p 0.001) as indicators for fatalities. In hospitalized patients acutely intoxicated with undifferentiated poisons, EDT as a parameter of left ventricle diastolic function and BNP are useful to early predict mortality.


Assuntos
Ecocardiografia/métodos , Peptídeo Natriurético Encefálico/metabolismo , Envenenamento/mortalidade , Xenobióticos/envenenamento , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Mortalidade Hospitalar , Hospitalização , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Envenenamento/fisiopatologia , Prognóstico , Estudos Prospectivos , Função Ventricular Esquerda , Adulto Jovem
8.
Rev Med Chir Soc Med Nat Iasi ; 120(2): 464-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27483736

RESUMO

Metformin is a widely used oral antidiabetic biguanide compound. According to the literature, metformin may lower the serum cyanocobalamin levels. We present the case of a 71-old-male treated with metformin for 15 years. When presenting to a periodic checkup, low serum cyanocobalamin levels where found. Laboratory tests showed levels below normal range for hemoglobin (12.7 g/dL) and hematocrit (37.8%). After patient reevaluation, a change in antidiabetic treatment will be considered if metformin will be found the cause of low serum cyanocobalamin levels. Other cases reported in the literature support this hypothesis, justifying the study of the influence of metformin therapy on serum vitamin B12 levels in patients diagnosed with diabetes. The influence of patient age, metformin dosage, duration of treatment and time since diabetes diagnosis on serum levels of vitamin B12 also need to be determined.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/efeitos adversos , Metformina/efeitos adversos , Deficiência de Vitamina B 12/etiologia , Vitamina B 12/sangue , Complexo Vitamínico B/sangue , Administração Oral , Idoso , Humanos , Hipoglicemiantes/administração & dosagem , Masculino , Metformina/administração & dosagem , Fatores de Tempo
9.
Biomed Pharmacother ; 83: 485-495, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27434864

RESUMO

Various formulations of anise-based bioadhesive gels are prepared. Freeze-drying method was successfully employed and superporous scaffolds were obtained. The resulting porous microarchitectures are strongly influenced by the composition of hydrogel formulations and temperature of freezing. Anise-based hydrogels frozen in liquid nitrogen and lyophilized generate regular assembly of polyhedral pores. For Carbopol 934-based hydrogels it was determined G'>G'' for whole tested strain amplitude range indicating solid-like behaviour due to their dense network and entanglement and interaction through hydrogen bonds and van-der Waals forces. For sodium alginate-based hydrogels it was determined G''>G' for whole tested strain amplitude range accompanied by the extended linear viscoelastic region indicating liquid-like behaviour due to the formation of a stable "pseudo-gel" structure. Biocompatibility features of tested hydrogels were evaluated by contact angle measurements and determination of surface tension parameters. It was found that all anise-based hydrogel formulations manifest modest activity against S. aureus and S. lutea and no activity against tested Gram negative bacteria. Carbopol 934-based hydrogels containing anise exhibit antifungal activity against C. albicans, C. glabrata and C. Parapsilosis.


Assuntos
Adesivos/farmacologia , Materiais Biocompatíveis/farmacologia , Hidrogéis/farmacologia , Pimpinella/química , Cremes, Espumas e Géis Vaginais/farmacologia , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Química Farmacêutica , Liofilização , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Reologia/efeitos dos fármacos , Tensão Superficial/efeitos dos fármacos , Termodinâmica , Fatores de Tempo
10.
Chem Cent J ; 10: 6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26855668

RESUMO

BACKGROUND: l-Arginine is a semi-essential aminoacid with important role in regulation of physiological processes in humans. It serves as precursor for the synthesis of proteins and is also substrate for different enzymes such as nitric oxide synthase. This amino-acid act as free radical scavenger, inhibits the activity of pro-oxidant enzymes and thus acts as an antioxidant and has also bactericidal effect against a broad spectrum of bacteria. RESULTS: New thiazolidine-4-one derivatives of nitro-l-arginine methyl ester (NO2-Arg-OMe) have been synthesized and biologically evaluated in terms of antioxidant and antibacterial/antifungal activity. The structures of the synthesized compounds were confirmed by (1)H, (13)C NMR, Mass and IR spectral data. The antioxidant potential was investigated using in vitro methods based on ferric/phosphomolybdenum reducing antioxidant power and DPPH/ABTS radical scavenging assay. The antibacterial effect was investigated against Gram positive (Staphylococcus aureus ATCC 25923, Sarcina lutea ATCC 9341) and Gram negative (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853) bacterial strains. The antifungal activity was also investigated against Candida spp. (Candida albicans ATCC 10231, Candida glabrata ATCC MYA 2950, Candida parapsilosis ATCC 22019). CONCLUSIONS: Synthesized compounds showed a good antioxidant activity in comparison with the NO2-Arg-OMe. The antimicrobial results support the selectivity of tested compounds especially on P. aeruginosa as bacterial strain and C. parapsilosis as fungal strain. The most proper compounds were 6g (R = 3-OCH3) and 6h (R = 2-OCH3) which showed a high free radical (DPPH, ABTS) scavenging ability and 6j (R = 2-NO2) that was the most active on both bacterial and fungal strains and also it showed the highest ABTS radical scavenging ability.Graphical abstract1: ethyl 3-aminopropionate hydrochloride, 2a-j: aromatic aldehydes, 3: thioglycolic acid, 4a-j: thiazolidine-propionic acid derivatives , 5: Nω-nitro-L-arginine methyl ester hydrochloride, 6a-j: thiazolidine-propionyl-nitro-L-arginine methyl ester derivatives.

11.
Carbohydr Polym ; 141: 28-40, 2016 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-26876993

RESUMO

Chitosan is a non-toxic, biocompatible, biodegradable natural cationic polymer known for its low imunogenicity, antimicrobial, antioxidant effects and wound-healing activity. To improve its therapeutic potential, new chitosan-sulfonamide derivatives have been designed to develop new wound dressing biomaterials. The structural, morphological and physico-chemical properties of synthesized chitosan derivatives were analyzed by FT-IR, (1)H NMR spectroscopy, scanning electron microscopy, swelling ability and porosity. Antimicrobial, in vivo testing and biodegradation behavior have been also performed. The chitosan derivative membranes showed improved swelling and biodegradation rate, which are important characteristics required for the wound healing process. The antimicrobial assay evidenced that chitosan-based sulfadiazine, sulfadimethoxine and sulfamethoxazole derivatives were the most active. The MTT assay showed that some of chitosan derivatives are nontoxic. Furthermore, the in vivo study on burn wound model induced in Wistar rats demonstrated an improved healing effect and enhanced epithelialization of chitosan-sulfonamide derivatives compared to neat chitosan. The obtained results strongly recommend the use of some of the newly developed chitosan derivatives as antimicrobial wound dressing biomaterials.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Bandagens , Quitosana/análogos & derivados , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/química , Antifúngicos/química , Porosidade , Ratos , Ratos Wistar , Molhabilidade
12.
Roum Arch Microbiol Immunol ; 75(1-2): 37-43, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29616532

RESUMO

With the emergence and spread of new methicilin resistant Staphylococcus aureus (MRSA) strains, control of dissemination, both in hospitals and in the community, requires the molecular characterization of the circulating strains in order to establish their dynamics and identify the sources of infection. During this study we analyzed the MRSA isolates by means of PCR-based methods in order to improve epidemiological surveillance and early application of prevention measures. The presence of mecA, nuc, lukF-PV and lukS-PV genes, as well as SCCmec types was assessed in relation to clinical characteristics and multidrug resistance (MDR) for 86 MRSA isolates and showed that 51% of MDR strains were carriers of mobile genetic elements SCCmec IV and the majority of non-MDR SCCmec type IV strains were PVL-positive (81.8%). Comparison of diagnostic methods showed that PBP2 detection represents an extremely useful alternative to PCR for the rapid screening of MRSA isolates, in laboratories that lack facilities necessary for molecular diagnosis, such as PFGE (Pulse Field Gel Electrophoresis), spa-typing and/or MLST (Multilocus Sequence Typing).


Assuntos
Staphylococcus aureus Resistente à Meticilina/classificação , Reação em Cadeia da Polimerase Multiplex/métodos , Fatores R/genética , Proteínas de Bactérias/genética , Transferência Genética Horizontal , Genes Bacterianos , Humanos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Proteínas de Ligação às Penicilinas/genética , Fenótipo , Romênia/epidemiologia , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia
13.
Rev Med Chir Soc Med Nat Iasi ; 120(4): 886-91, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-30141863

RESUMO

Methicillin-resistant Staphylococcus aureus can become resistant to many different classes of antibiotics. Objective: To characterize aminoglycoside and macrolide resistance mechanisms in MRSA strains in relation to antibiotic susceptibility patterns. Materials and methods: We tested 86 MRSA strains using multiplex PCR for detection of genes mecA, aac(6')-Ie/aph(2″), ant(4')-Ia, aph(3')-IIIa, ermA, ermC and msrA. Results: There was a prevalence of msrA (32.5%), ermC (30.2%) and aph(3')-IIIa (61.6%) genes, which are less frequently reported in MRSA. Most msrA genes was detected in PVL positive strains (92.8%) and was associated only with non-MDR strains, while ermC genes were associated with MDR strains. PVL producing strains were characterized by the presence of aph(3')-IIIa (93.1%) and msrA genes (93.1%), being phenotypically susceptible to clindamycin. Conclusions: Detection of aminoglycoside and macrolide resistance genes allowed us to establish the concordance between genotypic and phenotypic methods and to correlate the presence of certain resistance genes with the type of circulating strain and the production of virulence factors.


Assuntos
Aminoglicosídeos/farmacologia , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Genes Bacterianos , Macrolídeos/farmacologia , Staphylococcus aureus Resistente à Meticilina/genética , Infecções Estafilocócicas , Genótipo , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos , Fenótipo , Prevalência , Romênia/epidemiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia
14.
Int J Mol Sci ; 16(12): 29843-55, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26694354

RESUMO

The objective of this study was to develop new films based on chitosan functionalized with sulfonamide drugs (sulfametoxydiazine, sulfadiazine, sulfadimetho-xine, sulfamethoxazol, sulfamerazine, sulfizoxazol) in order to enhance the biological effects of chitosan. The morphology and physical properties of functionalized chitosan films as well the antioxidant effects of sulfonamide-chitosan derivatives were investigated. The chitosan-derivative films showed a rough surface and hydrophilic properties, which are very important features for their use as a wound dressing. The film based on chitosan-sulfisoxazol (CS-S6) showed the highest swelling ratio (197%) and the highest biodegradation rate (63.04%) in comparison to chitosan film for which the swelling ratio was 190% and biodegradation rate was only 10%. Referring to the antioxidant effects the most active was chitosan-sulfamerazine (CS-S5) which was 8.3 times more active than chitosan related to DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging ability. This compound showed also a good ferric reducing power and improved total antioxidant capacity.


Assuntos
Bandagens , Quitosana/farmacologia , Sulfonamidas/farmacologia , Cicatrização/efeitos dos fármacos , Antioxidantes/farmacologia , Compostos de Bifenilo/química , Depuradores de Radicais Livres/química , Processamento de Imagem Assistida por Computador , Testes de Sensibilidade Microbiana , Microscopia de Força Atômica , Oxirredução , Picratos/química , Propriedades de Superfície , Água/química
15.
PLoS One ; 10(11): e0143214, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26599338

RESUMO

This study presents the first characterization of carbapenem-non-susceptible Klebsiella pneumoniae isolates by means of a structured six-month survey performed in Romania as part of an Europe-wide investigation. Klebsiella pneumoniae clinical isolates from different anatomical sites were tested for antibiotic susceptibility by phenotypic methods and confirmed by PCR for the presence of four carbapenemase genes. Genome macrorestriction fingerprinting with XbaI was used to analyze the relatedness of carbapenemase-producing Klebsiella pneumoniae isolates collected from eight hospitals. Among 75 non-susceptible isolates, 65 were carbapenemase producers. The most frequently identified genotype was OXA-48 (n = 51 isolates), eight isolates were positive for blaNDM-1 gene, four had the blaKPC-2 gene, whereas two were positive for blaVIM-1. The analysis of PFGE profiles of OXA-48 and NDM-1 producing K. pneumoniae suggests inter-hospitals and regional transmission of epidemic clones. This study presents the first description of K. pneumoniae strains harbouring blaKPC-2 and blaVIM-1 genes in Romania. The results of this study highlight the urgent need for the strengthening of hospital infection control measures in Romania in order to curb the further spread of the antibiotic resistance.


Assuntos
Proteínas de Bactérias/biossíntese , Klebsiella pneumoniae/enzimologia , Inquéritos e Questionários , beta-Lactamases/biossíntese , Eletroforese em Gel de Campo Pulsado , Hospitais , Humanos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade Microbiana , Fenótipo , Romênia
16.
Rev Med Chir Soc Med Nat Iasi ; 119(2): 536-43, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26204664

RESUMO

AIM: The retro-prospective analysis of antibiotic sensitivity of non-fermenting gram negative bacilli strains circulating in the Orthopedics-Traumatology Clinic from "Sf. Spiridon" Emergency Clinical Hospital in view of determining the trend of the resistance phenomenon and indicating the most useful treatment for the infections caused by these strains. MATERIAL AND METHODS: The retrospective component was conducted from 01.01.2003 to 31.12.2012, and the result of the diffusimetric antibiograms was taken from the hospital's informatics system; the prospective component of the study involved the collection of pathological products from the patients admitted during January-December 2013, who showed clinical suspicion of infection, in compliance with the general collection norms for the products destined for the bacteriological exam. RESULTS: From the total 167 strains of Pseudomonas aeruginosa isolated and identified from the patients, 48 (28.74%) were sensitive to at least one antibiotic from each tested class, 29 (17.39%) were resistant to a single antibiotic and the rest of 90 (53.89%) showed multiple resistance. We noticed a statistically significant difference between the number of strains sensitive to at least one antibiotic from each tested class and those with multiple resistance (p < 0.05). For the strains of Acinetobacter baumanii combined resistance was identified for 121 (87.04%), out of which 55 (39.56%) were resistant to two classes of antibiotics and the other (47.48%) to all three classes. The most frequently met was the association of resistance to quinolones and aminoglycosides, namely for a number of 49 strains (35.25%); only 3.59% of them were simultaneously sensitive to the three classes of antibiotics. CONCLUSION: The already high percentages and the rising trends of antibiotic resistance of non-fermenting gram-negative bacteria described in this study confirm the continuous decrease of the efficiency of antimicrobial agents and underline the necessity of a global strategy which aims at all health sectors regarding the rational use of antibiotics, on the one hand, and the continuation of studies concerning the surveillance of the antimicrobial resistance phenomenon, on the other hand.


Assuntos
Antibacterianos/farmacologia , Infecção Hospitalar , Farmacorresistência Bacteriana Múltipla , Serviço Hospitalar de Emergência , Infecções por Bactérias Gram-Negativas , Ortopedia , Traumatologia , Infecções por Acinetobacter/tratamento farmacológico , Acinetobacter baumannii/efeitos dos fármacos , Aminoglicosídeos/farmacologia , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/epidemiologia , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/epidemiologia , Hospitais de Ensino , Humanos , Testes de Sensibilidade Microbiana/métodos , Estudos Prospectivos , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/efeitos dos fármacos , Quinolonas/farmacologia , Estudos Retrospectivos , Romênia/epidemiologia
17.
Rev Med Chir Soc Med Nat Iasi ; 119(1): 267-72, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25970977

RESUMO

AIM: This study aims to assess the microbial load of some medicinal plants (Matricaria chamomilla, Achillea millefolium, Ocimum basilicum, Calendula officinalis, Tilia cordata, Hypericum perforatum) commonly used as medicinal teas. MATERIAL AND METHODS: A total of 24 samples collected from the local market, as well as from the spontaneous flora of Galati County, were analyzed in terms of the total number of germs, the content of coliform bacteria, yeasts and molds, and the presence of specific pathogenic bacteria (Escherichia coli, Bacillus cereus, Coagulase-positive Staphylococcus, Salmonella spp.). RESULTS: The values obtained for total number of germs, yeasts and molds were in accordance with the limits set by the European Pharmacopoeia for plant products to which hot water is added before use. In the case of specific pathogenic bacteria, the presence of E. coli was confirmed in 41.66% of the samples, the presence of Coagulase-positive Staphylococcus in 16.66% of the samples, and the presence of Bacillus cereus in 33.33% of the samples. Salmonella spp. was absent in all samples. CONCLUSIONS: The study highlights a certain microbial load of medicinal plants analyzed, emphasizing the importance of quality control in all stages of production.


Assuntos
Fitoterapia , Plantas Medicinais/microbiologia , Bacillus cereus/isolamento & purificação , Contagem de Colônia Microbiana , Escherichia coli/isolamento & purificação , Humanos , Romênia , Salmonella/isolamento & purificação , Staphylococcus/isolamento & purificação
18.
Microb Drug Resist ; 21(6): 651-62, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25734920

RESUMO

Use of antibiotics in food animals may contribute to development and spread of resistant organisms, particularly so in some countries. The aim of this study was two-fold; first, to establish the prevalence of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli in chicken production in a region within Romania. Second, to study the relatedness of ESBL-producing E. coli isolates recovered from broilers, abattoir workers where the chickens were slaughtered and from the human clinical specimens from two regional hospitals. The results indicated a very high (69%) rate of carriage of ESBL and AmpC-producing E. coli in chickens with 36% CTX-M producers. Sequencing showed that chickens in Romania have the highest worldwide prevalence (53%) of blaCTX-M-15 reported in poultry E. coli isolates. The majority (53%) of the extended-spectrum cephalosporin-resistant E. coli carried plasmid-mediated blaampC genes, mostly blaCMY-2 type, one of the highest prevalences reported in Europe. The predominant CTX-M type found in the human clinical E. coli isolates was blaCTX-M-15 and most isolates coharbored blaOXA-1, blaTEM, and aac(6')-ib-cr. The majority (60%) of the human clinical isolates belonged to the pandemic virulent clone B2-ST131. The clonal relationship between broiler and the human CTX-M-producing E. coli isolates was assessed by macrorestriction pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST), which indicated strain diversity with no common STs found between human and poultry isolates. Moreover, IncI1 was the most prevalent replicon found in broiler ESBL-producing E. coli isolates and also in transconjugants, indicating that plasmids and not clonal spread may play a role in the transfer of blaCTX-M genes. This study identifies a high prevalence of ESBL-producing E. coli from broiler chickens in Romania with a high occurrence incidence of blaCTX-M-15, which reflects the main ESBL type found in human E. coli infections in this country.


Assuntos
Galinhas/microbiologia , Infecções por Escherichia coli/veterinária , Escherichia coli/efeitos dos fármacos , Plasmídeos/metabolismo , Doenças das Aves Domésticas/tratamento farmacológico , beta-Lactamases/genética , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cefalosporinas/farmacologia , Células Clonais , Eletroforese em Gel de Campo Pulsado , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Expressão Gênica , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Plasmídeos/química , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/microbiologia , Prevalência , Replicon/genética , Romênia/epidemiologia , beta-Lactamases/metabolismo
19.
Rev Med Chir Soc Med Nat Iasi ; 119(4): 1180-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26793867

RESUMO

AIM: To obtain some chalcones and their dibrominated analogues and to evaluate their antimicrobial potential. MATERIAL AND METHODS: Eight chalcones were synthesized using the Claisen-Schmidt condensation of acetophenone/4-bromo-acetophenone and different benzaldehyde derivatives. These chalcones were further brominated using two different bromination agents: molecular bromine and pyridinium tribromide. The antimicrobial activity was tested using the disk diffusion method. RESULTS AND DISCUSSIONS: The classical bromination technique was compared to the eco-friendly one using pyridinium tribromide. Pyridinium tribromide bromination did not improve the reaction yields (except for one compound), but it had the advantage of being a stable, non-corrosive and non-toxic salt. The results of the antimicrobial assessment indicated that the bromination of the double bond slightly increased the antimicrobial potential in some cases, but the results obtained during the antimicrobial evaluation were modest, some of the derivatives being active especially on Sarcina lutea ATCC 9341 and Bacillus cereus ATCC 14579. CONCLUSIONS: In this study, eight chalcones and their dibrominated analogues were synthesized, four of the α,ß-dibromochalcones being reported for the first time. Pyridinium tribromide was used as an alternative for liquid bromine, the main advantage of this method being related to the reduced toxicity of the reagents. The synthesized compounds did not exhibit a very good antimicrobial potential.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Bacillus cereus/efeitos dos fármacos , Chalconas/síntese química , Chalconas/farmacologia , Sarcina/efeitos dos fármacos , Acetofenonas/síntese química , Acetofenonas/química , Antibacterianos/química , Benzaldeídos/síntese química , Benzaldeídos/química , Chalconas/química , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Halogenação , Humanos , Piridinas
20.
Rev Med Chir Soc Med Nat Iasi ; 118(3): 780-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25341301

RESUMO

AIM: The retrospective analysis of antibiotic sensibility of S. aureus strains isolated from infected patients from the Orthopedics-Traumatology Clinic of "Sf. Spiridon" Clinical Emergency Hospital, Iasi during January 2003-December 2013, in view of determining the evolution trend of the resistance phenomenon and of pinpointing the most useful treatment for these strains. MATERIAL AND METHOD: The antibiotic sensitivity test was carried out using two methods: diffusimetric-Kirby-Bauer and the MIC determination by E-test (for the strains isolated in 2013); the interpretation of the sensitivity was made in a standardized manner, in compliance with the CLSI (Clinical and Laboratory Standards Institute) standard for antibiotics testing in force. RESULTS: The sensitivity testing for beta-lactams proved that during the 11 years of the study, the average value of the frequency of resistant strains was of 41.59% +/- 8.68. The highest frequency of MRSA (Methicillin Restant S. aureus) strains was noticed in 2012 (58.6%), followed by 2004 (50.7%). Even if in 2013 it dropped to 38.9%, the trend calculated for 2003-2013 is slightly rising (y = 0.0073x + 0.372). Out of the total of 495 S. aureus strains that were isolated, 164 (33.13%) were completely sensitive to the tested antibiotics and 26 (5.25%) were resistant only to beta-lactams. The other MRSA strains associated multiple resistance and MIC for vancomycin varied between 0.5-2 mg/ml. Two strains whose MIC was of 0.5 mg/ml were sensitive to most classes of tested antibiotics, including beta-lactams, except for macrolides (erythromycin), and the strain whose MIC was of 2 mg/ml, was resistant to all classes of tested antibiotics, except for glycopeptides and oxazolidiones. The other tested strains had a MIC for vancomycin equal to 1 mg/ml. CONCLUSIONS: Due to the fact that there are infections with SAMR strains in a rather worrying percentage (53.9%) that are resistant to the other classes of antibiotics, the only therapeutic solution being the vancomycin treatment, its use should be limited solely to those cases when it is really necessary. Fortunately, no vancomycin resistant MRSA strains have been identified in our country, but this phenomenon should be kept under close surveillance.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Serviço Hospitalar de Emergência , Testes de Sensibilidade Microbiana , Ortopedia , Staphylococcus aureus , Traumatologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana Múltipla , Hospitais Universitários , Humanos , Resistência a Meticilina , Testes de Sensibilidade Microbiana/métodos , Romênia/epidemiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/efeitos dos fármacos , Resistência a Vancomicina , Resistência beta-Lactâmica
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