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1.
BMC Infect Dis ; 20(1): 673, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938424

RESUMO

BACKGROUND: Urinary tract infection is one of the most common bacterial infections in children. Understanding the characteristics of uropathogens and their antimicrobial susceptibility pattern in a particular setting can provide evidence for the appropriate management of cases. This study aimed to assess the bacterial profile of urinary tract infection, their antimicrobial susceptibility pattern and associated factors among clinically suspected children attending at Felege-Hiwot Comprehensive Specialized Hospital, Northwest Ethiopia. METHODS: A hospital-based cross-sectional study was conducted from February-April, 2019. A systematic sampling technique was employed. A mid-stream urine sample was inoculated on cystine lactose electrolyte deficient media and incubated for 24-48 h. Sub-culturing was done on Mac-Conkey and blood agar. Antimicrobial susceptibility test was done on Muller-Hinton agar. A binary logistic regression model was used to see the association between dependent and independent factors. A p-value< 0.05 at 95% CI was considered as statistically significant. RESULTS: The overall prevalence of urinary tract infection was 16.7% (95% CI 12.4-21.1). Both Gram-negative and Gram-positive bacterial isolates were recovered with a rate of 44/50 (88%) and 6/50 (12%) respectively. Among Gram-negative isolates, E. coli 28/44(63.6%) was predominant while S. saprophyticus 2/6(33.3%) was prevalent among Gram-positive bacterial isolates. Overall, a high level of resistance to ampicillin, augmentin, and tetracycline was shown by Gram-negative bacteria with a rate of 44/44(100%), 39/44(88.6%), and36/44 (81.8%) respectively. About 33/50(66%) of overall multidrug resistance was observed (95% CI 52-78). About six Gram-negative bacterial isolates were extended spectrum beta-lactamase (ESBL) producers. Having a history of urinary tract infection (P-0.003, AOR 1.86-22.15) and male uncircumcision (p-0.00, AOR 5.5-65.35) were the independent variables that associate for urinary tract infections. CONCLUSION: In the present study, the prevalence of urinary tract infection among children was high and considerably a high proportion of multidrug resistance was observed. This result will have a significant impact on the selection of appropriate antimicrobial agents for the treatment of urinary tract infection.


Assuntos
Infecções Urinárias/diagnóstico , Adolescente , Antibacterianos/farmacologia , Criança , Pré-Escolar , Estudos Transversais , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Etiópia/epidemiologia , Feminino , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/isolamento & purificação , Hospitais , Humanos , Lactente , Masculino , Testes de Sensibilidade Microbiana , Razão de Chances , Estudos Prospectivos , Infecções Urinárias/microbiologia , beta-Lactamases/genética , beta-Lactamases/metabolismo
2.
Sci Rep ; 10(1): 13875, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32807805

RESUMO

Respiratory protection is key in infection prevention of airborne diseases, as highlighted by the COVID-19 pandemic for instance. Conventional technologies have several drawbacks (i.e., cross-infection risk, filtration efficiency improvements limited by difficulty in breathing, and no safe reusability), which have yet to be addressed in a single device. Here, we report the development of a filter overcoming the major technical challenges of respiratory protective devices. Large-pore membranes, offering high breathability but low bacteria capture, were functionalized to have a uniform salt layer on the fibers. The salt-functionalized membranes achieved high filtration efficiency as opposed to the bare membrane, with differences of up to 48%, while maintaining high breathability (> 60% increase compared to commercial surgical masks even for the thickest salt filters tested). The salt-functionalized filters quickly killed Gram-positive and Gram-negative bacteria aerosols in vitro, with CFU reductions observed as early as within 5 min, and in vivo by causing structural damage due to salt recrystallization. The salt coatings retained the pathogen inactivation capability at harsh environmental conditions (37 °C and a relative humidity of 70%, 80% and 90%). Combination of these properties in one filter will lead to the production of an effective device, comprehensibly mitigating infection transmission globally.


Assuntos
Filtros de Ar/microbiologia , Antibacterianos/química , Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Máscaras/microbiologia , Membranas Artificiais , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Dispositivos de Proteção Respiratória/microbiologia , Cloreto de Sódio/química , Aerossóis , Antibacterianos/farmacologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Cristalização , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Temperatura Alta , Humanos , Umidade , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Cloreto de Sódio/farmacologia
3.
Food Chem ; 332: 127391, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32603920

RESUMO

The objectives of the present work were to investigate the influence of Gum Arabic (GA) on the physicochemical properties and ultra-high temperature (UHT) processability of ß-lactoglobulin(ß-lg)-stabilized d-limonene emulsions. Moreover, we also wanted to evaluate the antimicrobial efficiency and mechanism of ß-lg-GA bilayer d-limonene emulsions. Physicochemically stable bilayer emulsions could be formed with an optimal concentration of GA (1.00 wt%), which showed a higher tolerance to both flocculation and coalescence, as well as better protective effects on d-limonene against UHT-treatment that up to 94.32% of d-limonene was retained in emulsions. Likewise, it is also noteworthy that no obvious difference in the minimal inhibitory concentration could be found between bilayer emulsions with or without UHT processing. Moreover, the antimicrobial effects of the bilayer emulsions with UHT treatment were shown to be dose-dependent, which was evidenced from the results of scanning electron microscopy and the determination of released cell constituents. Keywords: ß-lactoglobulin; gum arabic; d-limonene emulsion; physicochemical stability; UHT processability, antimicrobial efficiency.


Assuntos
Antibacterianos/química , Emulsões/química , Manipulação de Alimentos/métodos , Limoneno/química , Bicamadas Lipídicas/química , Antibacterianos/farmacologia , Elasticidade , Emulsões/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Goma Arábica/química , Temperatura Alta , Lactoglobulinas/química , Testes de Sensibilidade Microbiana , Viscosidade
4.
DNA Cell Biol ; 39(9): 1473-1477, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32721230

RESUMO

Global antibiotic resistance, driven by intensive antibiotic exposure/abuse, constitutes a serious challenge to all health care, particularly in an era when new antimicrobial development has slowed to a trickle. Recently, we published work demonstrating the discovery and partial mechanism of action of a novel bactericidal agent that is effective against both gram-positive and gram-negative multidrug-resistant bacteria. This drug, called AB569, consists of acidified nitrite (A-NO2-) and EDTA, of which there is no mechanism of resistance. Using both chemistry-, genetic-, and bioinformatics-based techniques, we first discovered that AB569 was able to generate bactericidal levels of nitric oxide (NO), while the EDTA component stabilized S-nitrosyl thiols, thereby furthering NO and downstream reactive nitrogen species production. This elegant chemistry triggered a paralytic downregulation of vital genes using RNA-seq involved in the synthesis of DNA, RNA, ATP, and protein in the representative ESKAPE pathogen, Pseudomonas aeruginosa.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Antibacterianos/química , Farmacorresistência Bacteriana , Ácido Edético/química , Bactérias Gram-Negativas/genética , Bactérias Gram-Positivas/genética , Nitritos/química
5.
Rev Col Bras Cir ; 47: e20202471, 2020.
Artigo em Português, Inglês | MEDLINE | ID: mdl-32667581

RESUMO

PURPOSE: the purpose of this research was to identify the sociodemographic and microbiological characteristics and antibiotic resistance rates of patients with diabetic foot infections, hospitalized in an emergency reference center. METHODS: it was an observational and transversal study. The sociodemographic data were collected by direct interview with the patients. During the surgical procedures, specimens of tissue of the infected foot lesions were biopsied to be cultured, and for bacterial resistance analysis. RESULTS: the sample consisted of 105 patients. The majority of patierns were men, over 50 years of age, married and with low educational level. There was bacterial growth in 95 of the 105 tissue cultures. In each positive culture only one germ was isolated. There was a high prevalence of germs of the Enterobacteriaceae family (51,5%). Gram-negative germs were isolated in 60% of cultures and the most individually isolated germs were the Gram-positive cocci, Staphylococcus aureus (20%) and Enterococcus faecalis (17,9%). Regarding antibiotic resistance rates, a high frequency of Staphylococcus aureus resistant to methicillin (63,0%) and to ciprofloxacin (55,5%) was found; additionally, 43,5% of the Gram-negative isolated germs were resistant to ciprofloxacin. CONCLUSIONS: the majority of patients were men, over 50 years of age, married and with low educational level. The most prevalent isolated germs from the infected foot lesions were Gram-negative bacteria, resistant to ciprofloxacin, and the individually most isolated germ was the methicillin resistant Staphylococcus aureus.


Assuntos
Antibacterianos/uso terapêutico , Pé Diabético/microbiologia , Bactérias Gram-Negativas/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/microbiologia , Bactérias Gram-Positivas/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/microbiologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Dermatopatias Bacterianas/microbiologia , Idoso , Antibacterianos/farmacologia , Complicações do Diabetes , Diabetes Mellitus , Pé Diabético/tratamento farmacológico , Resistência Microbiana a Medicamentos , Feminino , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Infecções , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Dermatopatias Bacterianas/tratamento farmacológico , Infecções Cutâneas Estafilocócicas/tratamento farmacológico , Infecções Cutâneas Estafilocócicas/epidemiologia , Infecções Cutâneas Estafilocócicas/microbiologia
6.
Ann Parasitol ; 62(2): 157-163, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32531148

RESUMO

Leishmaniosis is one of the most serious public health concern with a worldwide distribution. Since the current treatments of leishmaniosis are toxic and expensive, frequent studies have been conducted to investigate the benefits of new resources such as medicinal plants for treatment of this infectious disease. Recent studies revealed the antiparasitic potential of Rhus coriaria. Here we investigated the potential antileishmanial and antibacterial activities of the hydroalcoholic extract of R. coriaria fruits. The fruits were extracted using 80% methanol by maceration method. The concentrations of 312, 156, 78, and 37 µg/ml of the extract were added separately to the wells containing Leishmania major (L. major) promastigotes and amastigotes. Amphotericin B was considered as positive control. Finally, the death rate was determined for the extract-treated parasites as compared to the non-treated parasite. The antibacterial activity was evaluated by measurement of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extract against a set of Gram-positive and Gram-negative bacteria. The extract significantly inhibited the growth of both promastigotes (60,7%) and amastigotes (59%) at the concentration of 312 µg/ml with the IC50 values of 147 µg/ml and 233 µg/ml, respectively. The extract showed bactericidal effects against Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, and Acinetobacter baumannii. Totally, Grampositive bacteria were more susceptible to the extract. Our findings show that the hydroalcoholic extract of R. coriaria fruits are rich in tannins and can be considered for further in vivo studies on the antileishmanial and antibacterial activities especially on dermal lesions caused by L. major.


Assuntos
Antibacterianos/farmacologia , Antiprotozoários/farmacologia , Extratos Vegetais/farmacologia , Rhus/química , Frutas/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Leishmania major/efeitos dos fármacos
7.
Rev Soc Bras Med Trop ; 53: e20190106, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32578698

RESUMO

INTRODUCTION: The present study aimed to determine the incidence of health care-associated infections (HCAIs) and identify the main resistant microorganisms in intensive care unit (ICU) patients in a Brazilian university hospital. METHODS: A retrospective cohort study was conducted in a Brazilian teaching hospital between 2012 and 2014. RESULTS: Overall, 81.2% of the infections were acquired in the ICU. The most common resistant pathogenic phenotypes in all-site and bloodstream infections were oxacillin-resistant coagulase-negative staphylococci and carbapenem-resistant Acinetobacter spp. (89.9% and 87.4%; 80.6% and 70.0%), respectively. CONCLUSIONS: There is an urgent need to focus on HCAIs in ICUs in Brazil.


Assuntos
Antibacterianos/farmacologia , Bacteriemia/microbiologia , Farmacorresistência Bacteriana , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Adulto , Bacteriemia/mortalidade , Feminino , Bactérias Gram-Negativas/classificação , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/classificação , Bactérias Gram-Positivas/isolamento & purificação , Mortalidade Hospitalar , Humanos , Incidência , Unidades de Terapia Intensiva , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo
8.
PLoS One ; 15(5): e0233485, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32470050

RESUMO

Antimicrobial resistance is a growing global health and economic concern. Current antimicrobial agents are becoming less effective against common bacterial infections. We previously identified pyrrolocins A and C, which showed activity against a variety of Gram-positive bacteria. Structurally similar compounds, known as pyrrolidinediones (e.g., TA-289, equisetin), also display antibacterial activity. However, the mechanism of action of these compounds against bacteria was undetermined. Here, we show that pyrrolocin C and equisetin inhibit bacterial acetyl-CoA carboxylase (ACC), the first step in fatty acid synthesis. We used transcriptomic data, metabolomic analysis, fatty acid rescue and acetate incorporation experiments to show that a major mechanism of action of the pyrrolidinediones is inhibition of fatty acid biosynthesis, identifying ACC as the probable molecular target. This hypothesis was further supported using purified proteins, demonstrating that biotin carboxylase is the inhibited component of ACC. There are few known antibiotics that target this pathway and, therefore, we believe that these compounds may provide the basis for alternatives to current antimicrobial therapy.


Assuntos
Acetil-CoA Carboxilase/antagonistas & inibidores , Proteínas de Bactérias/antagonistas & inibidores , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/metabolismo , Pirrolidinonas/farmacologia , Tetra-Hidronaftalenos/farmacologia , Acetil-CoA Carboxilase/química , Antibacterianos/farmacologia , Proteínas de Bactérias/química , Domínio Catalítico/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Ácidos Graxos/biossíntese , Perfilação da Expressão Gênica , Bactérias Gram-Positivas/crescimento & desenvolvimento , Humanos , Metabolômica , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus aureus/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-32236389

RESUMO

The aim of this study was to determine the spontaneous decolonization period and characteristics in a prospective cohort of newborns colonized by multidrug-resistant organisms, after their discharge from the neonatal intensive care unit. Multidrug resistance is defined as bacterial non-susceptibility to ≥ 1 agent of ≥ 3 antimicrobial categories. In total, 618 newborns were included in the study, of which 173 (28.0%) presented a positive culture for multidrug-resistant microorganisms, and of these, 52 (30.1%) were followed up in this study. The most frequent intrinsic factors were be born by cesarean section (86.5%), prematurity (84.6%), and very low birth weight (76.9%). The extrinsic factors were having remained hospitalized for an average of 27 days, during which 67.3% were submitted to invasive procedures and 88.5% received antimicrobials. The intrinsic and extrinsic factors of newborns were not associated to a decolonization period longer or shorter than 3 months, which was the average period of decolonization found in the present study. From the totality of colonization cultures sampled at hospital discharge, the Gram-negative Extended Spectrum ß-lactamase producing bacteria were the most common, with 28.9% of babies colonized by Klebsiella spp. The median period of decolonization by multidrug-resistant microorganisms in the newborns population after hospital discharge was 3 months, but was highly dependent on the microbial species, and this period was not associated to any intrinsic and extrinsic factors of the newborn.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Estudos de Coortes , Feminino , Bactérias Gram-Negativas/classificação , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/classificação , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Masculino , Testes de Sensibilidade Microbiana , Alta do Paciente , Estudos Prospectivos , Fatores de Risco
10.
J Microbiol Biotechnol ; 30(3): 382-390, 2020 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-32238758

RESUMO

Periplanetasin-4 is an antimicrobial peptide with 13 amino acids identified in cockroaches. It has been reported to induce fungal cell death by apoptosis and membrane-targeted action. Analogs were designed by substituting arginine residues to modify the electrostatic and hydrophobic interactions accordingly and explore the effect of periplanetasin-4 through the increase of net charge and the decrease of hydrophobicity. The analogs showed lower activity than periplanetasin-4 against gram-positive and gram-negative bacteria. Similar to periplanetasin-4, the analogs exhibited slight hemolytic activity against human erythrocytes. Membrane studies, including determination of changes in membrane potential and permeability, and fluidity assays, revealed that the analogs disrupt less membrane integrity compared to periplanetasin-4. Likewise, when the analogs were treated to the artificial membrane model, the passage of molecules bigger than FD4 was difficult. In conclusion, arginine substitution could not maintain the membrane disruption ability of periplanetasin-4. The results indicated that the attenuation of hydrophobic interactions with the plasma membrane caused a reduction in the accumulation of the analogs on the membrane before the formation of electrostatic interactions. Our findings will assist in the further development of antimicrobial peptides for clinical use.


Assuntos
Membrana Celular/efeitos dos fármacos , Antibacterianos/farmacologia , Eritrócitos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas
11.
Microbes Environ ; 35(2)2020.
Artigo em Inglês | MEDLINE | ID: mdl-32269200

RESUMO

Atrazine is a triazine herbicide that is widely used to control broadleaf weeds. Its widespread use over the last 50 years has led to the potential contamination of soils, groundwater, rivers, and lakes. Its main route of complete degradation is via biological means, which is carried out by soil microbiota using a 6-step pathway. The aim of the present study was to investigate whether application of atrazine to soil changes the soil bacterial community. We used 16S rRNA gene sequencing and qPCR to elucidate the microbial community structure and assess the abundance of the atrazine degradation genes atzA, atzD, and trzN in a Brazilian soil. The results obtained showed that the relative abundance of atzA and trzN, encoding triazine-initiating metabolism in Gram-negative and -positive bacteria, respectively, increased in soil during the first weeks following the application of atrazine. In contrast, the abundance of atzD, encoding cyanuric acid amidohydrolase-the fourth step in the pathway-was not related to the atrazine treatment. Moreover, the overall soil bacterial community showed no significant changes after the application of atrazine. Despite this, we observed increases in the relative abundance of bacterial families in the 4th and 8th weeks following the atrazine treatment, which may have been related to higher copy numbers of atzA and trzN, in part due to the release of nitrogen from the herbicide. The present results revealed that while the application of atrazine may temporarily increase the quantities of the atzA and trzN genes in a Brazilian Red Latosol soil, it does not lead to significant and long-term changes in the bacterial community structure.


Assuntos
Atrazina/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Herbicidas/farmacologia , Microbiota/efeitos dos fármacos , Microbiologia do Solo , Biodegradação Ambiental , Brasil , Genes Bacterianos , Bactérias Gram-Negativas/classificação , Bactérias Gram-Positivas/classificação , RNA Ribossômico 16S/genética , Solo/química , Poluentes do Solo/farmacologia , Clima Tropical
12.
Biofouling ; 36(2): 222-233, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32316774

RESUMO

The antimicrobial activity of gold and silver nanoparticles (AuNPs, AgNPs), chitosan (CS) and their combinations was established by determining the minimum inhibitory concentration for planktonic (MICPC80) and biofilm growth (MICBC80), for biofilm formation (MICBF80), metabolic activity (MICBM80) and reduction (MICBR80), and for the metabolic activity of preformed biofilm (MICMPB80). Biofilms were quantified in microtitre plates by crystal violet staining and metabolic activity was evaluated by the MTT assay. Chitosan effectively suppressed biofilm formation (0.31-5 mg ml-1) in all the tested strains, except Salmonella enterica Infantis (0.16-2.5 mg ml-1) where CS and its combination with AgNPs induced biofilm formation. Nanoparticles inhibited biofilm growth only when the highest concentrations were used. Even though AuNPs, AgNPs and CS were not able to remove biofilm mass, they reduced its metabolic activity by at least 80%. The combinations of nanoparticles with CS did not show any significant positive synergistic effect on the tested target properties.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Quitosana/farmacologia , Ouro/farmacologia , Nanopartículas Metálicas/química , Prata/farmacologia , Antibacterianos/química , Biofilmes/crescimento & desenvolvimento , Quitosana/química , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Microbiologia de Alimentos , Ouro/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Prata/química
13.
BMC Infect Dis ; 20(1): 289, 2020 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-32306946

RESUMO

BACKGROUND: Gram-positive spectrum antibiotics such as vancomycin, teicoplanin, daptomycin, and linezolid are frequently used in empirical treatment combinations in critically ill patients. Such inappropriate and unnecessary widespread use, leads to sub-optimal utilisation. However they are covered by the antibiotics restriction programme. This prospective observational study, evaluates gram-positive anti-bacterial utilisations in intensive care units (ICUs) with various evaluation criteria, to determine the frequency of inappropriate usage and the intervention targets required to ensure optimum use. METHODS: This clinical study was conducted prospectively between 01.10.2018 and 01.10.2019 in the medical and surgical ICUs of Gazi University Faculty of Medicine Hospital, Turkey. The total bed capacity was 55. Patients older than 18 years and who were prescribed gram-positive spectrum antibiotics (vancomycin, teicoplanin, linezolid, and daptomycin) were included. Patients under this age or immunosuppressed patients (neutropenic,- HIV-infected patients with hematologic or solid organ malignancies) were not included in the study. During the study period, 200 treatments were evaluated in 169 patients. The demographic and clinical features of the patients were recorded. Besides observations by the clinical staff, the treatments were recorded and evaluated by two infectious diseases specialists and two clinical pharmacists at 24-h intervals from the first day to the last day of treatment. SPSS software for Windows, (version 17, IBM, Armonk, NY) was used to analyse the data. Categorical variables were presented as number and percentage, and non-categorical variables were presented as mean ± standard deviation. RESULTS: It was found that inappropriate gram-positive antibiotic use in ICUs was as high as 83% in terms of non-compliance with the selected quality parameters. Multivariate analysis was performed to evaluate the factors associated with inappropriate antibiotic use, increased creatinine levels were found to increase the risk of such use. CONCLUSIONS: In spite of the restricted antibiotics programme, inappropriate antibiotic use in ICUs is quite common. Thus, it is necessary to establish local guidelines in collaboration with different disciplines for the determination and follow-up of de-escalation of such use and optimal treatment doses.


Assuntos
Antibacterianos/uso terapêutico , Gestão de Antimicrobianos/normas , Bactérias Gram-Positivas/efeitos dos fármacos , Unidades de Terapia Intensiva/normas , Uso Excessivo de Medicamentos Prescritos/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Gestão de Antimicrobianos/estatística & dados numéricos , Revisão de Uso de Medicamentos , Feminino , Fidelidade a Diretrizes/estatística & dados numéricos , Humanos , Unidades de Terapia Intensiva/legislação & jurisprudência , Unidades de Terapia Intensiva/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Uso Excessivo de Medicamentos Prescritos/prevenção & controle , Estudos Prospectivos , Turquia
14.
Chemistry ; 26(34): 7657-7671, 2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32297355

RESUMO

A series of homoleptic and heteroleptic bismuth(III) flavonolate complexes derived from six flavonols of varying substitution have been synthesised and structurally characterised. The complexes were evaluated for antibacterial activity towards several problematic Gram-positive (Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant Enterococcus (VRE)) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria. The cell viability of COS-7 (monkey kidney) cells treated with the bismuth flavonolates was also studied to determine the effect of the complexes on mammalian cells. The heteroleptic complexes [BiPh(L)2 ] (in which L=flavonolate) showed good antibacterial activity towards all of the bacteria but reduced COS-7 cell viability in a concentration-dependent manner. The homoleptic complexes [Bi(L)3 ] exhibited activity towards the Gram-positive bacteria and showed low toxicity towards the mammalian cell line. Bismuth uptake studies in VRE and COS-7 cells treated with the bismuth flavonolate complexes indicated that Bi accumulation is influenced by both the substitution of the flavonolate ligands and the degree of substitution at the bismuth centre.


Assuntos
Antibacterianos/farmacologia , Bismuto/química , Complexos de Coordenação/química , Escherichia coli/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Animais , Antibacterianos/química , Escherichia coli/química , Bactérias Gram-Positivas/química , Humanos , Staphylococcus aureus Resistente à Meticilina/química , Pseudomonas aeruginosa/química , Staphylococcus aureus/química
15.
Int J Nanomedicine ; 15: 2353-2362, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32308387

RESUMO

Purpose: Simple methodology for preparation of metal nanoparticles such as AgNPs uses an methanolic aqueous medium at room temperature or a solvent-free procedure under microwave irradiation. The prepared AgNPs showed a significant antimicrobial effect against Gram-positive bacteria, Gram-negative bacteria, and fungi. Methods: The modified methoxypolyethylene glycol bishydrazino-s-triazine (mPEGTH2) showed remarkable activity for reducing Ag+ to Ag0 in an aqueous methanolic solution and using a solvent-free method (solid phase) under microwave irradiation. In the solid phase synthesis, the size and shape of the AgNPs can be controlled by varying the weight ratio of mPEGTH2 to AgNO3 used. In addition, the antimicrobial activity depends on the ratio of mPEGTH2 to AgNO3. The mPEGTH2-AgNPs (2:1) demonstrated higher antimicrobial activity compared to mPEGTH2-AgNPs (1:1) against Gram-positive bacteria, Gram-negative bacteria, and C.albicans. Results: This work presents simple methods for the synthesis of AgNPs using modified methoxypolyethylene glycol with bishydrazino-s-triazine (mPEGTH2); a solution method, using methanol-water medium at room temperature, and a solvent-free (solid phase) method, employing microwave irradiation or direct heating which could be used for the preparation of AgNPs on large scale. In the solid phase, ratios of mPEGTH2 to AgNO3 (1:1 or 2:1, respectively) are very important to control the size and shape of AgNPs. While in solution phase is not necessary where the molar ratio used is 10:1. Most of the experimental methods resulted in AgNPs ranging in size from 7 to 10 nm as observed from XRD and TEM characterization. The antimicrobial activity of the AgNPs was also dependent on the weight ratio of mPEGTH2 to AgNO3, with a large effect as observed when using the solvent-free method. The mPEGTH2-AgNPs (2:1) demonstrated higher antimicrobial activities compared to mPEGTH2-AgNPs (1:1) against S. aureus, S. epidermidis, E. faecalis, E. coli, P. aeruginosa, S. typhimurium, and C. albicans. In all cases, the MICs and MBCs of mPEGTH2-AgNPs (1:1) were lower than those of mPEGTH2-AgNPs (2:1). Conclusion: In summary, mPEGTH2-AgNPs (2:1) is a promising candidate to kill pathogenic microbes. In particular, the method used for the preparation of AgNPs by using polyethylene glycol polymer modified with bishydrazino-s-triazine has the most potential and would be the most cost-effective method. This method of the synthesis of nanoparticles may be suitable for the preparation of other metal nanoparticles, which would allow for numerous applications in medicinal and industrial.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Polietilenoglicóis/química , Prata/química , Antibacterianos/química , Candida albicans/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Micro-Ondas , Pseudomonas aeruginosa/efeitos dos fármacos , Técnicas de Síntese em Fase Sólida/métodos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos
16.
J Infect Public Health ; 13(4): 472-479, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32139293

RESUMO

BACKGROUND: The present work is an extension of ongoing efforts toward the development and identification of new molecules as monotherapy displaying anti-inflammatory and anti-infective activities and a wide-range of gastrointestinal selectivity. A series of novel set of trisubstituted thiazole compounds (AR-17a to AR-27a) have synthesized and evaluated for their in-vitro and in-vivo anti-inflammatory activities. Synthesized trisubstituted thiazole compounds were also evaluated for their potential antibacterial activity against clinical pathogens causing infectious disease. MATERIAL AND METHOD: The structures of synthesized compounds were characterized by FTIR, 1H NMR, Mass spectroscopic techniques and evaluated for their in-vitro and in-vivo anti-inflammatory effects using the human red blood cell (HRBC) membrane stabilization method and a carrageenan-induced rat paw oedema model, respectively, Diclofenac sodium and Ibuprofen were used as standard drugs. The synthesized compounds AR-17atoAR-27a screened for their in-vitro antibacterial activity against the gram-positive bacteria Staphylococcus aureus (ATCC25923) and Enterococcus faecalis (ATCC29212) and the gram-negative bacteria Escherichia coli (ATCC8739) and Pseudomonas aeruginosa (ATCC9027) using ciprofloxacin and cefdinir as standard drugs. RESULT: Compounds AR-17a and AR-27a elicited maximum anti-inflammatory activity, providing 59% and 61% protection at 20mg/kg, respectively, in the inflamed paw model. Among the tested compounds, AR-17a (6.25), (54) and AR-27a (1.56), (52) had the least minimum inhibitory concentration values and the highest zone of inhibition, indicating their marked antibacterial activities. The lowest conc. were observed at 1.56, 6.25µg/mL for inhibition of bacteria by most of the compounds. CONCLUSION: Novel set of trisubstituted thiazole compounds (AR-17a to AR-27a) have synthesized and characterized successfully. The preliminary screening revealed that these compounds possess promising anti-inflammatory and antibacterial activities. In addition, the objective of the study was achieved with few of the promising structures like AR-17a to AR-27a, which are prove to be potential monotherapy candidates for the treatment of chronic inflammatory diseases and bacterial infections.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Tiazóis/farmacologia , Animais , Antibacterianos/síntese química , Anti-Inflamatórios/síntese química , Edema/tratamento farmacológico , Feminino , Fluoroquinolonas/síntese química , Fluoroquinolonas/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Masculino , Testes de Sensibilidade Microbiana , Ratos , Relação Estrutura-Atividade , Tiazóis/síntese química
17.
J Med Microbiol ; 69(4): 605-616, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32125268

RESUMO

Introduction. Against the backdrop of increasing resistance to conventional antibiotics, bacteriocins represent an attractive alternative, given their potent activity, novel modes of action and perceived lack of issues with resistance.Aim. In this study, the nature of the antibacterial activity of a clinical isolate of Streptococcus gallolyticus was investigated.Methods. Optimization of the production of an inhibitor from strain AB39 was performed using different broth media and supplements. Purification was carried out using size exclusion, ion exchange and HPLC. Gel diffusion agar overlay, MS/MS, de novo peptide sequencing and genome mining were used in a proteogenomics approach to facilitate identification of the genetic basis for production of the inhibitor.Results. Strain AB39 was identified as representing Streptococcus gallolyticus subsp. pasteurianus and the successful production and purification of the AB39 peptide, named nisin P, with a mass of 3133.78 Da, was achieved using BHI broth with 10 % serum. Nisin P showed antibacterial activity towards clinical isolates of drug-resistant bacteria, including methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus and penicillin-resistant Streptococcus pneumoniae. In addition, the peptide exhibited significant stability towards high temperature, wide pH and certain proteolytic enzymes and displayed very low toxicity towards sheep red blood cells and Vero cells.Conclusion. To the best of our knowledge, this study represents the first production, purification and characterization of nisin P. Further study of nisin P may reveal its potential for treating or preventing infections caused by antibiotic-resistant Gram-positive bacteria, or those evading vaccination regimens.


Assuntos
Nisina/isolamento & purificação , Nisina/farmacologia , Streptococcus gallolyticus/metabolismo , Sequência de Aminoácidos , Animais , Cromatografia , Cromatografia Líquida de Alta Pressão , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Estrutura Molecular , Nisina/química , Nisina/metabolismo , Ovinos , Streptococcus gallolyticus/química , Streptococcus gallolyticus/classificação , Streptococcus gallolyticus/genética , Espectrometria de Massas em Tandem
18.
Georgian Med News ; (298): 132-137, 2020 Jan.
Artigo em Russo | MEDLINE | ID: mdl-32141866

RESUMO

This article presents the results of sensitivity/resistance of microbial strains isolated from three biotopes, in premature infants: mucous membranes of the respiratory tract, urinary system and colon after 72 hours after birth, as well as on the 14th and 30th day of life. During the study, total 677 strains of various microorganism species were isolated of which gram-positive flora - 386 microbial strains, almost 1.5 times predominated over gram-negative (291 strains) flora. Determination of sensitivity/resistance to antibiotics was carried out by two methods - a disc diffusion and a dilution methods on a solid nutrient medium. In the process of study of specificities of neonatal period, the influence of duration of antibiotic therapy, which newborns received during hospitalization period, was assessed. As a result, the number of schemes varied from 4 to 17, and the duration of treatment was 22-19 days. The most frequently used drugs were: Carbapenems, Glycopeptide, as well as third generation Cephalosporin and Aminoglicosides.


Assuntos
Antibacterianos/uso terapêutico , Carbapenêmicos/uso terapêutico , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/isolamento & purificação , Recém-Nascido Prematuro , Sistema Respiratório/microbiologia , Antibacterianos/farmacologia , Cefalosporinas/farmacologia , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Lactente , Recém-Nascido , Doenças do Prematuro , Testes de Sensibilidade Microbiana , Sistema Respiratório/efeitos dos fármacos
19.
BMC Complement Med Ther ; 20(1): 89, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32183792

RESUMO

BACKGROUND: Hydrolates, complex mixtures containing traces of essential oils (EOs), are inexpensive, easy to make and less toxic than their corresponding EOs. The antibacterial and antifungal activity of the hydrolate of Coridothymus capitatus (L.) Reichenb. fil. (Lamiaceae) alone and in combination with antimicrobial drugs, such as tetracycline and itraconazole, were evaluated. METHODS: The chemical composition was analysed by gas-chromatography-mass spectrometry (GC-MS). Standard methods were performed to evaluate the susceptibility of some Gram-positive and Gram-negative bacteria, and Candida spp. to the hydrolate, in comparison with its EO. The hydrolate mechanism of action was assayed by propidium iodide and MitoTracker staining. Checkerboard tests were carried out for combinations studies. RESULTS: GC-MS identified 0.14% (v/v) of total EO content into hydrolate and carvacrol as a dominant component. The hydrolate showed a good antimicrobial activity against bacteria and yeasts. It exhibited a synergistic effect with itraconazole against Candida krusei, and an additive effect with tetracycline against methicillin-resistant Staphylococcus aureus strains. Hydrolate changed the membranes permeability of bacteria and yeasts and altered mitochondrial function of yeasts. CONCLUSIONS: Our study extends the knowledge by exploiting non-conventional antimicrobial agents to fight the emergence of antibiotic resistance.


Assuntos
Anti-Infecciosos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Lamiaceae/química , Óleos Voláteis/farmacologia , Leveduras/efeitos dos fármacos , Antibacterianos/uso terapêutico , Anti-Infecciosos/química , Antifúngicos/uso terapêutico , Cromatografia Gasosa , Quimioterapia Combinada , Itraconazol/uso terapêutico , Espectrometria de Massas , Óleos Voláteis/química , Tetraciclina/uso terapêutico
20.
BMC Complement Med Ther ; 20(1): 86, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32183818

RESUMO

BACKGROUND: Myrtus communis is a typical plant of Mediterranean area. The different parts of this plant such as berries, branches, and leaves have been used worldwide as a traditional/folk medicine for the treatment of various ailments and diseases. METHODS: Ethanolic leaf extract of the plant was prepared by Soxhlet extraction method. Zone of inhibition, minimum inhibitory concentration and minimal bactericidal concentration were determined by well diffusion method and microplate alamar blue assay. GC-MS analysis was carried out to identify the compounds present in the extract. Microscopy and ImageJ software were used respectively for morphology and cell-length measurements. GraphPad Prism was used for statistical analysis. RESULTS: The ethanolic extract showed strong inhibitory effect against Gram-positive and acid-fast bacteria with significant inhibition-zone size (9-25 mm), MIC (4.87-78 µg/ml), as well as MBC (0.3-20 mg/ml). However, no effect was observed on the growth of Gram-negative bacteria. The growth inhibition was found to be associated with the damage of cell wall as the extract-treated cells were sensitive to cell wall-targeting antibiotics and displayed the cell wall damage-depicting morphological defects. GC-MS analysis confirmed the presence of novel compounds in addition to the most representative compounds of the essential oils/extracts of M. communis of other country origins. CONCLUSION: These results demonstrate that M. communis leaf extract could be the source of compounds to be used for the treatment of Gram-positive bacterial infections. This is the first report, which provides insights into the mechanism of action of the extract in inhibiting the growth of Gram-positive bacteria.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Positivas/efeitos dos fármacos , Myrtus/química , Extratos Vegetais/farmacologia , Antibacterianos/química , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Folhas de Planta/química , Arábia Saudita
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