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1.
Medicine (Baltimore) ; 98(37): e17157, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31517862

RESUMO

Antimicrobial resistance, a major threat to human health, is mainly driven by the overuse of antimicrobials. The purpose of this study was to further investigate the relationship between antimicrobial use and resistance with a 15-year record in Southwest hospital, one of the largest hospitals in Southwest China and a university affiliated hospital, thus to further predict the antimicrobial resistance in an autoregressive integrated moving average (ARIMA) manner. Kirby-Bauer tests were carried out to figure out the drug sensitivity of Gram-negative bacterial. Antimicrobials (ß-lactamase inhibitor complex, aminoglycosides, quinolones, third and fourth-generation cephalosporins, carbapenems, cephamycins, oxacephems, and sulfonamides) consumption were calculated according to World Health Organization (WHO) anatomical therapeutic chemical classification index and expressed as annual defined daily dose (DDD) or DDD per 1000 out patients. Resistance rates of levofloxacin-resistant Escherichia coli, ceftazidime-resistant Klebsiella pneumoniae, amikacin-resistant Bacterium levans, imipenem-resistant Pseudomonas aeruginosa is positively correlated with the usage of aminoglycosides and quinolones; resistance rates of imipenem-resistant Acinetobacter baumanii is positively correlated with the usage of carbapenemes (P-value between the drug resistance of levofloxacin-resistant E. coli, ceftazidime-resistant K. pneumoniae and the usage of aminoglycosides is under .05, the other P-value are under .01); resistance rates of the drug resistance of levofloxacin-resistant E. coli is positively correlated with the usage of oxacephems (P < .01); resistance rates of imipenem-resistant P. aeruginosa is positively correlated with the usage of oxacephems and sulfonamides (P < .01).The present study presents one of the largest and longest retrospective analyses in China between antimicrobial consumption and antimicrobial resistance. Change of the usage of several antibacterial drugs has great influence on the drug resistance of Gram-negative bacterial. Of particular, ARIMA forecasting revealed that carbapenem related bacterial resistance should be closely watched.


Assuntos
Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana , Uso de Medicamentos , Bactérias Gram-Negativas/efeitos dos fármacos , Aceitação pelo Paciente de Cuidados de Saúde , Monitoramento Epidemiológico , Hospitais Universitários , Humanos , Estudos Retrospectivos
2.
Adv Exp Med Biol ; 1145: 9-13, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31364068

RESUMO

Antibiotic resistance has presented a major health challenge in the world and many isolates of Enterobacteriaceae, Acinetobacter baumannii and Pseudomonas aeruginosa become resistant to almost all current antibiotics. This chapter provides an overview on the mechanisms of antibiotic resistance in these Gram-negative pathogens and outlines the formidable problem of the genetics of bacterial resistance. Prevalent multidrug-resistance in Gram-negative bacteria underscores the need for optimizing the clinical use of the last-line polymyxins.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Polimixinas/farmacologia , Acinetobacter baumannii/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Humanos , Pseudomonas aeruginosa/efeitos dos fármacos
3.
Adv Exp Med Biol ; 1145: 37-54, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31364070

RESUMO

The dry antibiotic development pipeline coupled with the emergence of multi-drug resistant Gram-negative 'superbugs' has driven the revival of the polymyxin lipopeptide antibiotics. Understanding the mode of action of antibiotics is an important precursor for optimizing their use and development. This chapter provides a concise treatise of the current knowledge-based on the primary mode of action of polymyxins as well as recent developments in understanding of bacterial cell responses and secondary modes of action.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Polimixinas/farmacologia
4.
Adv Exp Med Biol ; 1145: 197-218, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31364080

RESUMO

Polymyxin B is another clinically available polymyxin that has re-emerged in clinical practice to treat infections caused by multi-drug (MDR) or extensively-drug-resistant (XDR) Gram-negative bacteria (GNB). Its chemical structure is very similar to the structure of polymyxin E (colistin). However, since the latter is administered as a prodrug, there are major pharmacokinetic differences between both polymyxins that may potentially determine different clinical and microbiological outcomes. Studies addressing clinical or microbiological outcomes in patients treated with polymyxin B for MDR or XDR GNB are reviewed in this chapter.


Assuntos
Antibacterianos/uso terapêutico , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Polimixina B/uso terapêutico , Colistina , Farmacorresistência Bacteriana Múltipla , Bactérias Gram-Negativas/efeitos dos fármacos , Humanos
5.
An Acad Bras Cienc ; 91(3): e20180404, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365649

RESUMO

In this study, the antimicrobial, antioxidant and antitumor activity of ethanol extracts obtained from Phlomis russeliana (Sims.) Lag. ex Benth. (Lamiaceae) were evaluated. Disc diffusion and microdilution methods were used to test the extracts for antimicrobial activity against seven bacteria strains (Bacillus cereus ATCC 7064, Bacillus subtilis ATCC 6633, Staphylococcus aureus ATCC 6538P, Escherichia coli ATCC 10538, Proteus vulgaris ATCC 6899, Salmonella typhimurium CCM 5445 and Pseudomonas aeruginosa ATCC 27853) and four yeast strains (Kluyveromyces fragilis ATCC 8608, Rhodotorula rubra ATCC 70403, Debaryomyces hansenii DSM 70238 and Candida albicans ATCC 10239). Notably, they were more effective against the yeast strains than the bacterial strains. Of the yeast cultures, D. hanseii was among the most susceptible, having an inhibition zone of 16.2 mm with minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) of 64(128)µg/ml, respectively. For cytotoxic determination, Caco-2 cells were cultured as per ATCC protocol, and were treated with log concentrations (5-80 mg/ml) of P. russeliana. The potency of cell growth inhibition for each extract was expressed as an IC50 value. Moreover, oxidant capacity was evaluated via TOC assay. This product induced antiproliferative activity of 31.33% at 40 mg/ml and 20.96% at 80 mg/ml, without toxic effects on cells, although the oxidant capacity was decreased to 27.06 ± 0.7 nm in the 80 mg/ml-applied group compared to 47.9 ± 1.8 nm in the untreated one. Advanced pharmacological studies are needed to further evaluate P. russeliana for distinctive features.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Candida albicans/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Phlomis/química , Extratos Vegetais/farmacologia , Antibacterianos/isolamento & purificação , Antioxidantes/isolamento & purificação , Células CACO-2 , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Bactérias Gram-Negativas/classificação , Bactérias Gram-Positivas/classificação , Humanos , Turquia
6.
Mikrobiyol Bul ; 53(3): 254-261, 2019 Jul.
Artigo em Turco | MEDLINE | ID: mdl-31414627

RESUMO

Infections with multidrug resistant gram-negative bacteria is a growing problem especially in health care settings. Colistin is one of the last resort antibiotics for such infections in which treatment options are limited. Increasing resistance to colistin is a global problem. Clinical and Laboratory Standards Institute (CLSI) and the European Committee on Antimicrobial Susceptibility Testing (EUCAST) study groups have recommended the ISO-standard broth microdilution method (20776-1) as the reference method for the determination of colistin susceptibility. Since the broth microdilution method is not a practical method, it is rarely used in routine clinical microbiology laboratories, yet simple and accurate phenotypic detection methods for the determination of colistin resistance in routine microbiology laboratories are not precisely defined. The aim of this study was to evaluate BD Phoenix100 (Becton Dickinson, USA) system and colistin broth disk elution method for the detection of in vitro activity of colistin against gram-negative bacteria. A total of 419 gram-negative bacteria, including 199 Klebsiella pneumoniae, 163 Acinetobacter baumannii, 34 Escherichia coli, 20 Enterobacter spp., and three Citrobacter spp. isolates which were isolated from various clinical samples in our hospital between 2016-2018 were tested. The broth microdilution method was used as the reference method applying ISO-standard broth microdilution methods (20776-1) and CLSI/EUCAST recommendations. For colistin broth disk elution method, final concentrations of 0 (growth control), 1, 2 and 4 µg/ml were obtained by adding 10 µg colistin disks to four tubes containing 10 ml cation-adjusted Mueller Hinton broth per isolate. After incubation at room temperature for 30 minutes, 50 µl of standardized inoculum suspensions were added to the tubes. Colistin minimum inhibitor concentration (MIC) values were read visually after 16-20 hours of incubation at 35°C in ambient air. Manufacturer's recommendations were followed for BD Phoenix100 system. The categorical agreement between the reference broth microdilution method and the colistin broth disk elution method was 99.3%, very major error and major error rates were 0.2% and 0.5%, respectively. For BD Phoenix100 system, the categorical agreement was 95%, with a very major error rate of 5%. Our results showed that colistin broth disc elution method worked well compared to the reference broth microdilution method. The BD Phoenix100 system, with a high very major error rate, does not reliably distinguish colistin-resistant and colistin-susceptible strains.


Assuntos
Anti-Infecciosos , Colistina , Bactérias Gram-Negativas , Testes de Sensibilidade Microbiana , Anti-Infecciosos/farmacologia , Colistina/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Testes de Sensibilidade Microbiana/instrumentação , Testes de Sensibilidade Microbiana/métodos
8.
Rev Soc Bras Med Trop ; 52: e20180502, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31271619

RESUMO

INTRODUCTION: Plant products are sources for drug development against multidrug resistant bacteria. METHODS: The antimicrobial activity of Origanum vulgare L. essential oil (OVeo) against carbapenem-resistant strains was assessed by disk-diffusion, microdilution (REMA-Resazurin Microtiter Assay), and time kill assays. RESULTS: Carbapenemase production was confirmed for all strains. OVeo exhibited a minimum inhibitory concentration of 0.059% v/v for Klebsiella pneumoniae and Serratia marcescens, and of 0.015 % v/v for Acinetobacter baumannii. A decrease in cell count was observed after a 4 h treatment. CONCLUSIONS: OVeo antimicrobial effect was rapid and consistent, making it a candidate for developing alternative therapeutic options against carbapenem-resistant strains.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Klebsiella pneumoniae/efeitos dos fármacos , Óleos Voláteis/farmacologia , Origanum/química , Serratia marcescens/efeitos dos fármacos , Acinetobacter baumannii/crescimento & desenvolvimento , Antibacterianos/classificação , Proteínas de Bactérias , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana Múltipla , Bactérias Gram-Negativas/crescimento & desenvolvimento , Humanos , Klebsiella pneumoniae/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Serratia marcescens/crescimento & desenvolvimento , beta-Lactamases
9.
Medicina (B Aires) ; 79(3): 167-173, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-31284250

RESUMO

Diabetic foot infections are related to severe complications and constitute the main reason for diabetes-related hospitalization and lower limb amputations. A diabetic foot infection requires prompt actions to avoid progression of the infected wound; a soft tissue sample has to be taken for microbiological culture and empiric antibiotic therapy must be started immediately. Empiric antibiotic schemes should be chosen based on the severity of the infection and the local prevalence of microbial causal agents. Therefore, it is important to monitor these indicators. The aim of this study was to determine which microorganisms were more prevalent in cultures of diabetic foot infections during 2018 and what antibiotic combination was better to cover local microbiology, compared with data available from 2015 for a similar cohort. A total of 68 positive cultures were obtained of 72 soft tissue specimens analyzed. The most frequent microorganisms were Gram negative (47.1%), and resulted significantly more frequent than in 2015 (24.6%) p = 0.01. These Gram negative germs also resulted more sensitive to ciprofloxacin than in 2015 (62.5% vs. 25.0%) p = 0.03. Amoxicillin-clavulanate plus ciprofloxacin was the optimal combination therapy in 2018, while in 2015 it was amoxicillin-clavulanate plus trimethoprim sulfamethoxazole. In agreement with these results, we recommend amoxicillin-clavulanate plus ciprofloxacin as the empiric antibiotic regimen of choice for soft tissue infections in diabetic foot. We consider surveillance of local microbiology to be an important tool in the management of diabetic foot infections.


Assuntos
Combinação Amoxicilina e Clavulanato de Potássio/uso terapêutico , Antibacterianos/uso terapêutico , Ciprofloxacino/uso terapêutico , Pé Diabético/tratamento farmacológico , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Pé Diabético/etiologia , Pé Diabético/microbiologia , Quimioterapia Combinada , Bactérias Gram-Negativas/classificação , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/microbiologia
10.
J Photochem Photobiol B ; 197: 111541, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31272033

RESUMO

Here, we report the novel fabrication of ZnO nanoparticles using the Costus igneus leaf extract. Gas chromatography-mass spectrometry (GC-MS) and proton nuclear magnetic resonance (1H NMR) spectroscopy to determine the bioactive components present in the plant extract. The synthesis of Ci-ZnO NPs (C. igneus- coated zinc oxide nanoparticles) was accomplished using a cost-effective and simple technique. Ci-ZnO NPs were specified using UV-visible spectroscopy, FTIR, XRD, and TEM. Ci-ZnO NPs was authenticated by UV-Vis and exhibited a peak at 365 nm. The XRD spectra proved the crystalline character of the Ci-ZnO NPs synthesized as hexagonal wurtzite. The FTIR spectrum illustrated the presence of possible functional groups present in Ci-ZnO NPs. The TEM micrograph showed evidence of the presence of a hexagonal organization with a size of 26.55 nm typical of Ci-ZnO NPs. The α-amylase and α-glucosidase inhibition assays demonstrated antidiabetic activity of Ci-ZnO NPs (74 % and 82 %, respectively), and the DPPH [2,2-diphenyl-1-picrylhydrazyl hydrate] assay demonstrated the antioxidant activity of the nanoparticles (75%) at a concentration of 100 µg/ml. The Ci-ZnO NPs exhibited promising antibacterial and biofilm inhibition activity against the pathogenic bacteria Streptococcus mutans, Lysinibacillus fusiformis, Proteus vulgaris, and Vibrio parahaemolyticus. Additionally, the Ci-ZnO NPs showed biocompatibility with mammalian RBCs with minimum hemolytic activity (0.633 % ±â€¯0.005 %) at a concentration of 200 µg/ml.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/química , Biofilmes/efeitos dos fármacos , Nanopartículas Metálicas/química , Extratos Vegetais/química , Óxido de Zinco/química , Antibacterianos/síntese química , Antibacterianos/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Costus/química , Costus/metabolismo , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/fisiologia , Química Verde , Hemólise/efeitos dos fármacos , Humanos , Insulina/química , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Extratos Vegetais/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo
11.
J Photochem Photobiol B ; 197: 111548, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31288120

RESUMO

The visible light combined with photosensitizers (PSs) is exploited in both antitumoral and antimicrobial fields inducing a photo-oxidative stress within the target cells. Among the different PSs, porphyrins belong to the family of the most promising compounds to be used in clinical photodynamic applications. Although in the last years many porphyrins have been synthesised and tested, only a few reports concern the in vitro effects of the 5,15-diarylporphyrins. In this work, the activity of four 5,15-diarylporphyrins (compounds 7-10), bearing alkoxy-linked pyridinium appendixes, have been tested on cancer cell lines and against bacterial cultures. Among the synthetized PSs, compounds 7 and 9 are not symmetrically substituted porphyrins showing one cationic charge tethered at the end of one 4C or 8C carbon chains, respectively. On the other hand, compounds 8 and 10 are symmetrically substituted and show two chains of C4 and C8 carbons featuring a cationic charge at the end of both chains. The dicationic 8 and 10 were more hydrophilic than monocationic 7 and 9, outlining that the presence of two pyridinium salts have a higher impact on the solubility in the aqueous phase than the lipophilic effect exerted by the length of the alkyl chains. Furthermore, these four PSs showed a similar rate of photobleaching, irrespective of the length and number of chains and the number of positive charges. Among the eukaryotic cell lines, the SKOV3 cells were particularly sensitive to the photodynamic activity of all the tested diarylporphyrins, while the HCT116 cells were found more sensitive to PSs bearing C4 chain (7 and 8), regardless the number of cationic charges. The photo-induced killing effect of these porphyrins was also tested against two different bacterial cultures. As expected, the Gram positive Bacillus subtilis was more sensitive than the Gram negative Escherichia coli, and the dicationic porphyrin 8, bearing two C4 chains, was the most efficient on both microorganisms. In conclusion, the new compound 8 seems to be an optimal candidate to deepen as versatile anticancer and antibacterial photosensitizer.


Assuntos
Antibacterianos/química , Antineoplásicos/química , Fármacos Fotossensibilizantes/química , Porfirinas/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Cátions/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Luz , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/síntese química , Porfirinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo
12.
J Photochem Photobiol B ; 197: 111556, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31326842

RESUMO

Facile green synthesis of copper nanoparticles from different biological procedures has been indicated, but among all, biosynthesis of copper nanoparticles from medicinal plants is considered as the most suitable method. The use of medicinal plant material increases the therapeutical effects of copper nanoparticles. The aim of this study was green synthesis of copper nanoparticles from aqueous extract of Falcaria vulgaris leaf (CuNPs) and assessment of their cytotoxicity, antioxidant, antifungal, antibacterial, and cutaneous wound healing properties. These nanoparticles were characterized by X-ray diffraction (XRD), fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV), transmission electron microscopy (TEM), and field emission scanning electron microscopy (FE-SEM) analysis. The synthesized CuNPs had great cell viability dose-dependently (Investigating the effect of the CuNPs on human umbilical vein endothelial cell (HUVEC) line) and indicated this method was nontoxic. Also, 2,2-diphenyl-1-picrylhydrazyl (DPPH) test was done to assess the antioxidant activities, which indicated similar antioxidant potentials for CuNPs and butylated hydroxytoluene. In part of cutaneous wound healing property of CuNPs, after creating the cutaneous wound, the rats were randomly divided into six groups: treatment with 0.2% CuNPs ointment, treatment with 0.2% CuSO4 ointment, treatment with 0.2% F. vulgaris ointment, treatment with 3% tetracycline ointment, treatment with Eucerin basal ointment, and untreated control. These groups were treated for 10 days. Treatment with CuNPs ointment remarkably increased (p ≤ .01) the wound contracture, vessel, hexosamine, hydroxyl proline, hexuronic acid, fibrocyte, and fibrocytes/fibroblast rate and substantially reduced (p ≤ .01) the wound area, total cells, neutrophil, and lymphocyte compared to other groups. In antibacterial and antifungal parts of this research, the concentration of CuNPs with minimum dilution and no turbidity was considered minimum inhibitory concentration (MIC). To determine minimum fungicidal concentration (MFC) and minimum bactericidal concentration (MBC), 60 µL MIC and three preceding chambers were cultured on Sabouraud Dextrose Agar and Muller Hinton Agar, respectively. The minimum concentration with no fungal and bacterial growth were considered MFC and MBC, respectively. CuNPs inhibited the growth of all fungi at 2-4 mg/mL concentrations and removed them at 4-8 mg/mL concentrations (p ≤ .01). In case of antibacterial effects of CuNPs, they inhibited the growth of all bacteria at 2-8 mg/mL concentrations and removed them at 4-16 mg/mL concentrations (p ≤ .01). The results of XRD, FT-IR, UV, TEM, and FE-SEM confirm that the aqueous extract of F. vulgaris leaf can be used to yield copper nanoparticles with notable amount of antioxidant, antifungal, antibacterial, and cutaneous wound healing potentials without any cytotoxicity. Further clinical trials are necessary for confirmation these therapeutical effects of CuNPs in human.


Assuntos
Apiaceae/química , Cobre/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/farmacologia , Antioxidantes/química , Apiaceae/metabolismo , Candida/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Folhas de Planta/química , Folhas de Planta/metabolismo , Ratos , Pele/efeitos dos fármacos , Pele/patologia , Cicatrização/efeitos dos fármacos
13.
J Photochem Photobiol B ; 197: 111554, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31326843

RESUMO

Bovine mastitis is an endemic disease of dairy cattle that is considered to be one of the most frequent and costly diseases in veterinary medicine. An increase in the incidence of disease results in the increased use of antibiotics, which in turn increases the potential of bacterial resistance. This study aimed to investigate the effectiveness of antimicrobial photodynamic therapy (aPDT) in the treatment of bovine mastitis, as an alternative to systemic antibiotics. To identify the key factors affecting photoinactivation efficacy, realistic experiments in view of the end-use were conducted in milk samples using two different photosensitizers: methylene blue (MB) and silicon (IV) phthalocyanine derivative (SiPc). We explored the effects of divalent ions and fat content on the aPDT outcome and determined influence of different proteins on aPDT efficacy. Levels of bacterial sensitivity to PSs varied depending on the type of bacteria (Gram-positive vs. Gram-negative) and light exposure time. Critical interrelated factors affecting aPDT in milk were identified and an efficient combination of treatment conditions that can lead to a full photodynamic inactivation of bacteria was determined.


Assuntos
Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Leite/microbiologia , Fármacos Fotossensibilizantes/farmacologia , Animais , Bovinos , Feminino , Indóis/química , Indóis/farmacologia , Indóis/uso terapêutico , Luz , Mastite Bovina/tratamento farmacológico , Mastite Bovina/microbiologia , Mastite Bovina/patologia , Azul de Metileno/farmacologia , Azul de Metileno/uso terapêutico , Proteínas do Leite/química , Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Oxigênio Singlete/metabolismo
14.
Chem Pharm Bull (Tokyo) ; 67(7): 620-631, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31257316

RESUMO

Natural products are still rich sources of clinically used medicines and lead compounds for them. This review summarizes chemical studies carried out by the author on natural products of microorganism origin, many of which were discovered at the Institute of Microbial Chemistry (BIKAKEN). Caprazamycin B is a liponucleoside antibiotic from which CPZEN-45, an antituberculosis agent with a unique mode of action, was developed. Intervenolin and leucinostatin A exert antiproliferative activity toward tumor cells in the presence of the corresponding stromal cells, which implies that the primary molecular targets of these molecules should be related to growth signals from normal (stromal) cells. Details of the endeavors to establish efficient synthetic routes to these compounds which accelerated structure-activity relationship studies and further evaluation of biological activity are described.


Assuntos
Anti-Infecciosos/química , Antineoplásicos/química , Produtos Biológicos/química , Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Azepinas/química , Azepinas/farmacologia , Produtos Biológicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Peptídeos/química , Peptídeos/farmacologia , Relação Estrutura-Atividade
15.
Zhonghua Er Ke Za Zhi ; 57(7): 553-558, 2019 Jul 02.
Artigo em Chinês | MEDLINE | ID: mdl-31269557

RESUMO

Objective: Analyze the changes of indicator of antimicrobial usage and detection rate of multidrug-resistant gram-negative bacteria (MDR-GNB), in order to evaluate the impact of antimicrobial stewardship program (ASP). Methods: The antimicrobial stewardship program was implemented since December 2011 at the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University. Intensified effort was made from 2014 to 2017. We divided the program into four stages, one before ASP (2010-2011) and three after ASP (2012-2013 as the first, 2014-2015 as the second and 2016-2017 as the third post-ASP stages). The usage rates in outpatient,emergency department and inpatient, along with the antibiotic use density (AUD, defined as daily doses/per 100 patient-days), the AUD of the third-generation cephalosporins and carbapenems in inpatient were reviewed retrospectively. The detection rates of extended-spectrum ß-lactamases (ESBLs)-producing Escherichia coli, ESBLs-producing Klebsiella pneumonia, carbapenem-resistant E. coli, carbapenem-resistant Klebsiella pneumonia, carbapenem-resistant Acinetobacter baumannii and carbapenem-resistant Pseudomonas aeruginosa were also analyzed at the same time. The correlation analysis between the detection rate of MDR-GNB and the indicator of antimicrobial usage was made. Result: Among four stages, the usage rates were 55.2% (560 578/1 015 540) , 38.1% (493 554/1 296 336) , 26.8% (378 602/1 411 595) and 23.1% (347 817/1 502 817) in outpatient, 75.6% (429 582/568 230) , 61.4% (382 558/623 138) , 43.6% (265 102/608 071) and 35.1% (218 484/622 397) in emergency department, and 76.0% (30 568/40 221) , 53.7% (30 437/56 636) , 49.9% (37 395/74 895) and 50.3% (35 493/70 544) in inpatient, respectively. All indicators decreased significantly (χ(2)=297 811.798, 3 155 704.783, 5 592.037, P<0.01). The AUD in inpatient was 38.4,31.8,21.7 and 19.41,and the AUD of the third-generation cephalosporins were 13.83, 11.21, 6.20 and 6.84, respectively, which decreased significantly after ASP (r=-0.878, -0.781, P<0.05). The AUD of carbapenems were 1.94,1.77,1.87 and 1.93, respectively (r=0.123, P>0.05). A total of 11 289 strains of bacteria were collected, including 5 589 strains of E. coli, 2 823 strains of K.pneumoniae, 1 637 strains of A. baumandii, and 1 240 strains of P. aeruginosa.The detection rates of ESBLs-producing E.coli and ESBLs -producing K. pneumoniae in four stages were 75.4% (1 034/1 371) , 66.6% (893/1 341) , 57.8% (834/1 443) , 46.7% (670/1 434) and 78.7% (547/695) , 67.5% (455/674) , 49.3% (421/854) , 32.5% (195/600) , respectively,both decreased significantly (χ(2)=266.204; 328.805, P<0.01). The detection rates of Carbapenem-resistant A. baumannii were 28.2% (115/408) , 26.7% (126/472) , 24.3% (125/515) and 12.0% (29/242) respectively,and showed significant decreasing trend after ASP (χ(2)=18.112, P<0.01). The detection rates of carbapenem-resistant P. aeruginosa were 11.3% (40/355) , 18.5% (58/313) , 13.4% (46/343) and 7.0% (16/229) , respectively,with the most obvious decrease in the third stage after ASP. The detection rates of carbapenem-resistant E. coli and carbapenem-resistant K. pneumonia were continuously lower (<5%). There were positive correlations between the detection rates of ESBLs-producing E. coli and K. pneumoniae and all usage indicators (r(1)=0.930, 0.974, 0.746, 0.958, 0.842; r(2)=0.910, 0.960, 0.765, 0.963, 0.898, P<0.05). Conclusion: The antimicrobial stewardship program can effectively reduce both the usage of antimicrobial and the production of MDR-GNB, which has great value to promote rational clinical use of antimicrobials and reduce bacterial resistance.


Assuntos
Antibacterianos/farmacologia , Gestão de Antimicrobianos , Bactérias Gram-Negativas/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Criança , Farmacorresistência Bacteriana , Escherichia coli , Bactérias Gram-Negativas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Avaliação de Programas e Projetos de Saúde , Estudos Retrospectivos
16.
J Nanobiotechnology ; 17(1): 84, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31291944

RESUMO

BACKGROUND: Nanoceria has recently received much attention, because of its widespread biomedical applications, including antibacterial, antioxidant and anticancer activity, drug/gene delivery systems, anti-diabetic property, and tissue engineering. MAIN BODY: Nanoceria exhibits excellent antibacterial activity against both Gram-positive and Gram-negative bacteria via the generation of reactive oxygen species (ROS). In healthy cells, it acts as an antioxidant by scavenging ROS (at physiological pH). Thus, it protects them, while in cancer cells (under low pH environment) it acts as pro-oxidant by generating ROS and kills them. Nanoceria has also been effectively used as a carrier for targeted drug and gene delivery in vitro and in vivo models. Besides, nanoceria can also act as an antidiabetic agent and confer protection towards diabetes-associated organ pathophysiology via decreasing the ROS level in diabetic subjects. Nanoceria also possesses excellent potential in the field of tissue engineering. In this review, firstly, we have discussed the different methods used for the synthesis of nanoceria as these are very important to control the size, shape and Ce3+/Ce4+ ratio of the particles upon which the physical, chemical, and biological properties depend. Secondly, we have extensively reviewed the different biomedical applications of nanoceria with probable mechanisms based on the literature reports. CONCLUSION: The outcome of this review will improve the understanding about the different synthetic procedures and biomedical applications of nanoceria, which should, in turn, lead to the design of novel clinical interventions associated with various health disorders.


Assuntos
Cério/química , Nanopartículas/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Cério/farmacologia , Sistemas de Liberação de Medicamentos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Engenharia Tecidual/métodos
17.
Chem Biodivers ; 16(8): e1900183, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31361076

RESUMO

This work describes the study of the chemical composition and bioactivity of the essential oils (EOs) of the different organs (leaves, flowers, stems and roots) from Eruca vesicaria. According to the GC and GC/MS analysis, all the EOs were dominated by erucin (4-methylthiobutyl isothiocyanate) with a percentage ranging from 17.9 % (leaves) to 98.5 % (roots). The isolated EOs were evaluated for their antioxidant (DPPH, ABTS and ß-carotene/linoleic acid), antibacterial and inhibitory property against α-amylase and α-glucosidase. Most EOs exhibited an interesting α-glucosidase and α-amylase inhibitory potential. The roots essential oil was found to be the most active with IC50 values of 0.80±0.06 and 0.11±0.01 µg mL-1 , respectively. The essential oil of roots exhibited the highest antioxidant activity (DPPH, PI=92.76±0.01 %; ABTS, PI=78.87±0.19; and ß-carotene, PI=56.1±0.01 %). The isolated oils were also tested for their antibacterial activity against two Gram-positive and three Gram-negative bacteria. Moderate results have been noted by comparison with Gentamicin used as positive control.


Assuntos
Antioxidantes/química , Brassicaceae/metabolismo , Óleos Voláteis/química , Antibacterianos/química , Antibacterianos/farmacologia , Brassicaceae/química , Flores/química , Flores/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hipoglicemiantes/química , Óleos Voláteis/metabolismo , Óleos Voláteis/farmacologia , Folhas de Planta/química , Folhas de Planta/metabolismo , Raízes de Plantas/química , Raízes de Plantas/metabolismo , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo
18.
BMC Infect Dis ; 19(1): 585, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31277588

RESUMO

BACKGROUND: Antibiotic resistance is a worldwide problem that crosses international boundaries and spread between continents easily. Hence, information on the existence of the causative microorganisms and their susceptibility to commonly used antibiotics are essential to enhance therapeutic outcome. METHOD: A cross-sectional study was conducted retrospectively at Hawassa University Comprehensive Specialized Hospital. The culture and antibiotic sensitivity data of the isolates were collected from the record books of the microbiology unit for the study period after official permission obtained from the institutional review board. The data entered and analyzed using statistical package for social science software version 20. RESULT: A total of 693 bacteria were retrieved, of these 435(62.77%) were gram-negative and the rest 258(37.23%) were gram-positive. Most of the isolates were from a urine sample. Among gram positives isolates, S. aureus and from gram negatives Klebsiella spp are the most recurrent isolate. Almost a remarkable resistance was observed to most of the antibiotics mainly, penicillin G (81.8%) and cotrimoxazole (81.1%), for gram-positive bacteria. The gram-negative bacteria also show resistance to ampicillin (92.5%), tetracycline (85%) and cotrimoxazole (93.1%). CONCLUSIONS: Nearly all isolate show substantial rates of resistance to most of the antibiotic that is frequently used in the study area. As already known we want to emphases on the importance of performing continuous monitoring of drug susceptibility to help the empirical treatment of bacterial agents to a health professional in the region. In addition, this data might help policymakers to control of antibiotics resistance.


Assuntos
Farmacorresistência Bacteriana/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Adolescente , Adulto , Idoso , Antibacterianos/farmacologia , Criança , Pré-Escolar , Estudos Transversais , Etiópia , Feminino , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Hospitais Especializados , Hospitais Universitários , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Retrospectivos , Centros de Atenção Terciária
19.
Pan Afr Med J ; 32: 166, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31303935

RESUMO

Introduction: Superbugs are pathogenic micro-organism and especially a bacterium that has developed resistance to the medications normally used against it. As the superbug family increases, the need for appropriate diagnostic, treatment, prevention and control strategies cannot be over emphasized. Therefore, this work determined the distribution of superbug bacteria among patients on prolonged hospital admissions in three tertiary hospitals of Kano state, Nigeria. Methods: A descriptive cross sectional study was undertaken among 401 patients from medical, surgery, orthopedic and burn centre wards in a three tertiary hospitals in Kano state. A sample collected comprises wound/pus, urine, urine catheter and nasal intubation and were analysed using standard microbiological methods for Acinetobacter spp and other related nosocomial bacterial pathogens. Antibiotic susceptibility testing was done using Kirby-Bauer disc diffusion method. Results: One hundred and thirty eight (138) isolates were recovered, from the studied participants. More than 80% of the nosocomial infections (NIs) were caused by Gram-negative bacteria, predominantly Escherichia coli, Klebseilla spp, Proteus spp, Pseudomona spp and Acinetobacter spp. In-vitro antibiotic susceptibility test revealed that acinetobacter were 100% resistant to amoxicillin, co-trimoxazole, perfloxacin and imipenem. Conclusion: Superbugs (Acinetobacter species) significantly contributed to delayed hospital admissions through observed 100% resistance to used antibiotics. The healthcare managers of these hospitals and the ministry of health need to take measures against this resistant bacteria (Acinetobacter spp) especially on prescribing antibiotics that showed 100% resistant from these studied hospitals.


Assuntos
Antibacterianos/farmacologia , Infecções Bacterianas/epidemiologia , Infecções por Bactérias Gram-Negativas/epidemiologia , Hospitalização/estatística & dados numéricos , Adolescente , Adulto , Idoso , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Estudos Transversais , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência Bacteriana Múltipla , Feminino , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Nigéria/epidemiologia , Centros de Atenção Terciária , Fatores de Tempo , Adulto Jovem
20.
BMC Complement Altern Med ; 19(1): 141, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31221162

RESUMO

BACKGROUND: Antimicrobial resistance (AMR) remains an important global health issue but the gap between AMR and development of new antimicrobials is increasing. Plant extracts may have good activity per se or may be sources of effective antimicrobial compounds which can act against planktonic and/or biofilms of pathogens. We determined the antimicrobial efficacy and cytotoxicity of some under-investigated plants from the Myrtaceae family endemic to South Africa. The ability of the plant extracts to inhibit or destroy pre-formed bacterial biofilms was also determined. METHODS: Based on previous preliminary in vitro screening and on chemotaxonomy, nine species from the Myrtaceae family were selected. The antimicrobial activity of the crude acetone leaf extracts was determined against six common nosocomial pathogens, namely: Gram-positive bacteria (Bacillus cereus, Enterococcus faecalis, Staphylococcus aureus), Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Salmonella Typhimurium) using a two-fold serial microdilution assay with p-iodonitrotetrazolium violet as growth indicator. The number of antimicrobial compounds present in extracts was determined by bioautography. Cytotoxicity of extracts was determined against Vero kidney cells using a colorimetric tetrazolium-based assay. The total antibacterial activity (TAA) in ml/g and selectivity index (LC50/MIC) of the plant extracts were calculated. A modified crystal violet assay was used to determine the antibiofilm activity of the extracts. RESULTS: Syzygium legatii, Syzygium masukuense, and Syzygium species A had the best activities against Gram-negative and Gram-positive bacteria (MIC) values ranging from 0.04-0.08 mg/ml. Eugenia erythrophylla had the best MIC (0.02 mg/ml) against Bacillus cereus. Many extracts had relatively low cytotoxicity (LC50 > 20 µg/ml) leading to reasonable selectivity indices. Three leaf extracts (Syzygium masukuense, Syzygium species A, and Eugenia natalitia) were moderately cytotoxic (20 µg/ml < LC50 < 100 µg/ml). The plant extracts had a good capacity to reduce biofilm formation and good to poor potential to destroy pre-formed biofilms. CONCLUSIONS: The plant species examined in this study had varying degrees of antibacterial activity against bacterial planktonic and biofilm forms with some having good activity against both forms. Several of these selected species may be potential candidates for further investigation to isolate antimicrobial compounds and to determine the mechanism of activity.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Extratos Vegetais/farmacologia , Syzygium/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/fisiologia , Dose Letal Mediana , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , África do Sul
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