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1.
Food Microbiol ; 85: 103295, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31500701

RESUMO

Fermented red pepper (FRP) sauce has been eaten in worldwide for many years. The salt content and resident microbial community influences the quality of the FRP sauce and may confer health (e.g., probiotics) or harm (e.g., antibiotic resistance genes) to the consumers in some circumstances; however, the salt-mediated alteration of microbial community and antibiotic resistance genes are little known. In this study, a combination of whole genome sequencing and amplicon analysis was used to investigate the changes in microbial community and antimicrobial resistance genes in response to different salt content during red pepper fermentation. While the family Enterobacteriaceae dominated in high-salt (15-25%) samples, Lactobacillaceae quickly became the dominant population in place of Enterobacteriaceae after 24 days in 10% salt samples. Compared to 0.05 antibiotic resistance genes (ARGs) per cell number on average in 10% salt sample, 16.6 ARGs were present in high-salt samples, wherein the bacterial hosts were major assigned to Enterobacteriaceae including genera Enterobacter, Citrobacter, Escherichia, Salmonella and Klebsiella. Multidrug resistance genes were the predominant ARG type. Functional profiling showed that histidine kinase functions were of much higher abundance in high-salt samples and included several osmotic stress-related two-component systems that simultaneously encoded ARGs. These results give first metagenomic insights into the salt-mediated changes in microbial community composition and a broad view of associated antibiotic resistance genes in the process of food fermentation.


Assuntos
Capsicum/química , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/genética , Lactobacillaceae/genética , Metagenoma , Microbiota , Cloreto de Sódio/química , Enterobacteriaceae/crescimento & desenvolvimento , Fermentação , Genes Bacterianos , Lactobacillaceae/crescimento & desenvolvimento , Metagenômica , Pressão Osmótica
2.
Sci Total Environ ; 700: 134446, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31648121

RESUMO

Bacteriophage may play an important role in antimicrobial resistance genes (ARGs) transmission. However, the contribution of bacteriophage to the spread of ARGs in environment, especially in poultry farm environment, is rarely known. In this study, the prevalence of ARGs in bacteriophage DNA was investigated in chicken feces from 30 different poultry farms in China. Then the abundance of the aac(6')-Ib-cr, blaCTX-M, ermB, floR, mcr-1, sul1, tetM and intI1 genes was determined by qPCR in bacteriophage and compared with certain representative plasmid DNA samples. The results showed that 12 ARGs (aac(6')-Ib-cr, aph(3')-IIIa, blaCTX-M, ermB, ermF, floR, mcr-1, qnrS, sul1, sul2, vanA, tetM genes) and class 1 integron gene intI1 were detected in bacteriophage DNA fraction. The sul1, tetM and aac(6')-Ib-cr genes were most prevalent with high detection rates of 77%, 61% and 55%, respectively. To our best knowledge, this study firstly reported the presence of the mcr-1 gene in bacteriophage DNA derived from farms environments. We found that the gene copy (GC) numbers of the aac(6')-Ib-cr, ermB and sul1 genes were as high as 5.47, 5.22 and 5.54 log10 GC/g, respectively. Both the prevalence and abundance of ARGs in broiler fecal wastes were also generally higher than in laying hens. In addition, although the GC numbers of the aac(6')-Ib-cr, floR and tetM genes in plasmid DNA was higher than that in phage DNA fraction by 4.68, 3.59 and 3.9 orders of magnitude, respectively, the absolute abundances of the blaCTX-M and mcr-1 genes in phage DNA were close to or even higher than that in plasmid DNA at farm SIL2, SIL4 and SIB1. As potential vessels for ARGs, bacteriophage could not be ignored due to their unique extracellular persistence in environments. Overall, this is the first comprehensive survey about bacteriophage carried ARGs from farms in different regions in China.


Assuntos
Farmacorresistência Bacteriana/genética , Fezes/virologia , Genes Bacterianos , Animais , Bacteriófagos/genética , Galinhas , China , Fazendas , Integrons , Plasmídeos
3.
J Colloid Interface Sci ; 559: 313-323, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31675662

RESUMO

Antibiotic resistance is a common phenomenon observed during treatment with antibacterials. Use of nanozymes, especially those with synergistic enzyme-like activities, as antibacterials could overcome this problem, but their synthesis is limited by their high cost and/or complex production process. Herein, vanadium oxide nanodots (VOxNDs) were prepared via a one-step bottom-up ethanol-thermal method using vanadium trichloride as the precursor. VOxNDs alone possess bienzyme mimics of peroxidase and oxidase. Accordingly, highly efficient antibacterials against drug-resistant bacteria can be obtained through synergistic catalysis; the oxidase-like activity decomposes O2 to generate superoxide anion radical (O2-) and hydroxyl radicals (OH), and the intrinsic peroxidase-like activity can further induce the production of OH from external H2O2. Consequently, H2O2 concentration could decrease up to four magnitude orders with VOxNDs to achieve an antibacterial efficacy similar to that of H2O2 alone. Wound healing in vivo further confirms the high antibacterial efficiency, good biocompatibility, and application potential of the synergistic antibacterial system due to the "nano" structure of VOxNDs. The method of synthesis of nanodot antibacterials described in this paper is inexpensive, and the results of this study reveal the multi-enzymatic synergism of nanozymes.


Assuntos
Antibacterianos/química , Nanopartículas Metálicas/química , Óxidos/química , Compostos de Vanádio/química , Cicatrização/efeitos dos fármacos , Animais , Materiais Biocompatíveis/química , Materiais Biomiméticos/química , Catálise , Sobrevivência Celular/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Células HeLa , Células Endoteliais da Veia Umbilical Humana , Humanos , Peróxido de Hidrogênio/química , Radical Hidroxila/química , Peroxidases/metabolismo , Ratos Sprague-Dawley , Staphylococcus aureus/efeitos dos fármacos
4.
Huan Jing Ke Xue ; 41(1): 313-320, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854932

RESUMO

Wastewater treatment plants hold a vast pool of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs). The aim of this study is to analyze the ARB and ARGs in a pharmaceutical and chemical wastewater treatment plant using a metagenomic technique. The results of taxonomic annotation revealed that bacteria were the predominant domain. The most abundant phyla and genus was Proteobacteria and Hyphomicrobium, respectively. A total of 74 categories of ARGs were predicted using CARD with the most dominant types being sav 1866, dfrE, and mfd. Furthermore, a network analysis was conducted to investigate the co-occurrence patterns between ARGs and microbial taxa. ARGs were found to be highly connected to microbial taxa at the genus level. With respect to the antibiotic resistance mechanisms, antibiotic-specific efflux pumps appeared to be the most common mechanisms. Among these, resistance-nodulation-cell division (RND) was the major type. The most important functional pathway of this microbial community was metabolic correlation. Interestingly, there were many genes related to human diseases, among which bacterial infectious diseases were the main ones. On the one hand, these data further confirmed that pharmaceutical and chemical wastewater treatment plants are rich in ARB and ARGs. The accumulation of ARGs increases the potential environmental risks, and hence it is necessary to strengthen the active monitoring of ARB and ARGs in pharmaceutical and chemical wastewater treatment plants. On the other hand, research on ARB and ARGs offers important information for the selection of deep processing technology to effectively remove ARB and ARGs.


Assuntos
Bactérias/classificação , Farmacorresistência Bacteriana , Genes Bacterianos , Águas Residuárias , Purificação da Água , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Humanos , Metagenoma , Preparações Farmacêuticas
5.
Ann Otol Rhinol Laryngol ; 129(1): 5-11, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31390881

RESUMO

OBJECTIVES: Intranasal septal splints are often used in nasal septal surgeries. Routine use of postoperative antibiotics is an accepted practice, although data regarding its efficacy in preventing postsurgical complications are limited. This study aimed to examine bacterial colonization on septal splints following prophylactic antibiotic therapy and the association with postoperative infections. METHODS: Fifty-five patients underwent septoplasty by a single surgeon between March 2015 and April 2016. All had intranasal septal splints and were given antibiotic prophylaxis for 7 days until removal of splints. Nasal cultures were taken before surgery, and septal splints were examined for bacterial colonization following their removal. RESULTS: Thirty-six patients (65%) had positive nasal culture prior to surgery. The most common isolates were Staphylococcus aureus (30%) and Enterobacteriaceae species (66%). All these patients had postoperative bacterial colonization on septal splints. In 15 patients with negative preoperative cultures, bacteria were isolated postoperatively. An increased resistance profile was documented postoperatively in 9 patients (16%), including two with multidrug resistance. In two of these patients preoperative wild-type strains acquired antibiotic resistance postoperatively. No adverse drug reactions to antibiotics were reported. CONCLUSIONS: Increased bacterial growth and emergence of resistant strains were observed on intranasal septal splints despite prophylactic antibiotic treatment. Nonetheless, this did not translate into clinical infection. Thus, considering antibiotics overuse and increasing bacterial resistance, further research is needed to determine the role of antibiotic prophylaxis in the setting of intranasal splints.


Assuntos
Antibacterianos/uso terapêutico , Antibioticoprofilaxia , Cavidade Nasal/microbiologia , Septo Nasal/cirurgia , Procedimentos Cirúrgicos Nasais/métodos , Contenções/microbiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Adolescente , Adulto , Idoso , Combinação Amoxicilina e Clavulanato de Potássio/uso terapêutico , Cefalexina/uso terapêutico , Técnicas de Cultura , Farmacorresistência Bacteriana , Farmacorresistência Bacteriana Múltipla , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/isolamento & purificação , Infecção da Ferida Cirúrgica/epidemiologia , Adulto Jovem
6.
APMIS ; 128(1): 20-24, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31630449

RESUMO

A case of bacteremia with the fastidious bacteria Actinomyces urogenitalis following lengthy urinary retention is reported in a sixty-year-old man. In 2013, the first case of bacteremia due to A. urogenitalis was presented, secondary to a tubo-ovarian abscess following transvaginal oocyte retrieval. To the best of our knowledge, this is the first male bacteremic episode involving A. urogenitalis related to a urinary tract focus. The patient had no prior urogenital medical history. Extensive susceptibility testing was done on isolates from urinary and blood cultures. The organism exhibited fluoroquinolone resistance but was susceptible to most other antibiotics used in the treatment of urinary infections. Due to its unusual growth requirements infections with A. urogenitalis are most likely an underdiagnosed entity.


Assuntos
Actinomicose/diagnóstico , Bacteriemia/microbiologia , Retenção Urinária/complicações , Infecções Urinárias/microbiologia , Actinomyces , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Farmacorresistência Bacteriana , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Resultado do Tratamento
7.
APMIS ; 128(1): 41-47, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31692136

RESUMO

Campylobacteriosis is one of the most frequently reported zoonoses worldwide. The well-documented increase in the ciprofloxacin resistance has increased the importance of rapid detection of the resistance. The incidence of ciprofloxacin resistance was investigated using real-time PCR. Identification of one hundred and fifty-eight strains was performed by PCR. Minimum inhibitory concentration (MIC) of ciprofloxacin was determined by Epsilometer test. Following the confirmation of the efficiencies of singleplex real-time PCR methods using two different probes, a cytosine to thymine point mutation at codon 86 was detected by allelic discrimination. Of the 158 strains, 114 (72.2%) were determined to be resistant to ciprofloxacin. The MIC50 and the MIC90 of ciprofloxacin were found to be 8 and ≥32 mg/L, respectively. By real-time PCR, the presence of the mutation was confirmed in all, but one, resistant strains and the absence of the mutation was demonstrated in all, but one, susceptible strains. The rate of resistance is high among C. jejuni strains and ciprofloxacin should not be used in the treatment of such infections in Turkey. A cytosine to thymine mutation is the most frequently detected mechanism for the resistance. Real-time PCR can be used for the quick screening of the resistance.


Assuntos
Antibacterianos/farmacologia , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/genética , Ciprofloxacino/farmacologia , Farmacorresistência Bacteriana/genética , Mutação Puntual , Alelos , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Eletroforese em Gel de Campo Pulsado , Humanos , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Fenótipo , Prevalência , Turquia
8.
APMIS ; 128(1): 48-60, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31693234

RESUMO

Klebsiella pneumoniae is an important opportunistic pathogen with significant potential for virulence and multidrug resistance. Treatment failure often occurs because the pathogen may couple virulence and drug resistance with the stringent response. This study assessed the role of the spoT gene in environmental and nutritional stress tolerance, exopolysaccharide capsule production and biofilm formation. spoT mutants were constructed using the lambda red recombinase technique, and mutant and wild-type (WT) strains were exposed to limiting concentrations of carbon (glucose), phosphate and aminoacid, and environmental stresses of ethanol, salt and heat. Cell viability, capsule production and cell length were assessed as well as the ability to grow biofilm under antibiotic pressure using gentamicin and ceftazidime. spoT mutants were more susceptible to stresses versus WT; the reverse was true for survival during biofilm susceptibility assay (p < 0.05), especially when carbon and phosphate were present. spoT mutants were elongated and lacked a capsule versus WT and non-starved strains. The inability to produce capsule in mutants before and after starvation was likely a general effect of spoT mutation. These data suggest that the spoT-mediated stringent response is important for K. pneumoniae in conditions of nutrient limitation, environmental stress and antimicrobial pressure.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Biofilmes/crescimento & desenvolvimento , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/fisiologia , Estresse Fisiológico , Aminoácidos/química , Farmacorresistência Bacteriana , Etanol/farmacologia , Regulação Bacteriana da Expressão Gênica , Glucose/química , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Fosfatos/química , Cloreto de Sódio/farmacologia , Virulência/genética , Fatores de Virulência
9.
Expert Rev Pharmacoecon Outcomes Res ; 19(6): 685-692, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31847613

RESUMO

Introduction: Governments need to do far more to help curb the emergence and transmission of antibiotic resistance and help protect the efficacy of any new antibiotics that come to the market. Industry is an important stakeholder that must be brought on-board such efforts given its influence on the direction and scale of antibiotic sales. Financial incentives supporting industry R&D of novel antibiotics should structurally remove the drivers of superfluous sales and encourage access to newer antibiotics where infections are otherwise resistant to treatment. Indeed, the use of public money provides an important opportunity to prioritize these public health goals within market structures such that we both adequately reward industry for their efforts and prolong antibiotic efficacy for as long as possible.Areas covered: This work discusses possible financial 'pull' incentives that fully delink the reward paid to the developer from unit sales, examining their primary advantages and limitations.Expert opinion: Pharmaceutical companies need to be rewarded generously for their efforts to develop new, badly needed antibiotics. But the current marketplace does not provide a sustained financial lure and its reliance on unit-sales for profitability jeopardizes the efficacy of antibiotics both new and old. Fully delinked models can make antibiotic R&D more financially appealing and create a market environment that is far less threatening to public health.


Assuntos
Antibacterianos/farmacologia , Indústria Farmacêutica/economia , Farmacorresistência Bacteriana , Antibacterianos/economia , Comércio/economia , Desenvolvimento de Medicamentos/economia , Humanos , Saúde Pública/economia , Apoio à Pesquisa como Assunto/economia
10.
Bratisl Lek Listy ; 120(12): 935-940, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31855054

RESUMO

OBJECTIVES: We focused on detecting the most frequent resistance mechanisms in selected multidrug-resistant (MDR) strains and determining their antimicrobial resistance. BACKGROUND: MDR pathogens pose urgent public health threat due to limited treatment options, rigorous control measures and significant mortality. METHODS: We confirmed extended-spectrum ß-lactamase (ESBL) and carbapenemase producing Enterobacteriaceae through guidelines, as well following ß-lactamases: AmpC by cloxacillin, class A carbapenemase with phenylboronic acid, class B metallo-ß-lactamase with ethylenediaminetetraacetic acid. Multilocus sequence typing was used to investigate 20 Escherichia coli strains. RESULTS: Overall 205 mostly ESBL Escherichia coli demonstrated resistance against amikacin (4.7 %), tigecycline (1.2 %), and no resistance to ceftazidime/avibactam, meropenem, nitrofurantoin and fosfomycin. Out of 41 Klebsiella species (spp.), 37 (90.2 %) showed carbapenemase activity, 13 (35.1 %) of class A and 24 (64.9 %) of class B. Resistance was following: meropenem 66.7 %, tigecyclin 10.2 % and colistin 0 %. From Enterobacter spp. 21 strains, 14 (66.7 %) were ESBL, 5 produced ESBL and/or AmpC and 2 were MDR. We ascertained 14 (70 %) E. coli sequence type - ST131. CONCLUSIONS: The study revealed various resistance mechanisms in concert with different agents and association of specific ST131 within E. coli. These characteristics considerably contribute to emergence of antimicrobial resistance (Tab. 4, Ref. 30).


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriaceae/enzimologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Klebsiella pneumoniae/efeitos dos fármacos , beta-Lactamases/metabolismo , Adulto , Idoso , Proteínas de Bactérias/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/enzimologia , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Farmacorresistência Bacteriana , Enterobacteriaceae/classificação , Infecções por Enterobacteriaceae/microbiologia , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Humanos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , beta-Lactamases/genética
11.
Wiad Lek ; 72(11 cz 1): 2069-2075, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31860848

RESUMO

OBJECTIVE: Introduction: Bloodstream infections (BSIs) are associated with high morbidity and mortality worldwide. However data of BSI from Ukraine are scarce. The aim: To obtain the first national estimates of the current incidence of BSI and antimicrobial resistance of responsible pathogens, and associated mortality in Ukraine. PATIENTS AND METHODS: Materials and methods: A retrospective multicenter cohort study was conducted at the 14 hospitals of Ukraine between January 2013 to December 2015. Definitions of BSIs were adapted from the CDC. The identification and antimicrobial susceptibility of cultures were determined, using automated microbiology analyzer. Some antimicrobial susceptibility test used Kirby - Bauer antibiotic testing. RESULTS: Results: Among 20,544 patients, 3816 (18.6%) BSIs were observed. The rate of health care associated BSI was 92.4%. Death was reported in 68.4% BSI cases. The predominant pathogens were: Klebsiella pneumoniae (25.1%), Escherichia coli (17.5%), Staphylococcus aureus (9.9%), Pseudomonas aeruginosa (8.9%), and Acinetobacter spp.(8.5%). The overall proportion of extended spectrum beta-lactamase (ESBL) production among Enterobacteriaceae was 24.8% and of methicillin-resistance in S. aureus (MRSA) 38.2%. Vancomycin resistance was observwd in 9.2% of isolated enterococci (VRE). Carbapenem resistance was identified in 33.1% of P.aeruginosa isolates and 63.2% of A. baumannii isolates. Resistance to third-generation cephalosporins was observed in 14.2% K. pneumoniae and E.coli 55% isolates. CONCLUSION: Conclusions: Healthcare-associated BSIs and antimicrobial resistance of responsible pathogens together with their associated impact on mortality, presents a significant burden to the Ukraine hospital system. Surveillance of BSIs may help to delineate the requirements for infection prevention and control.


Assuntos
Bacteriemia , Infecção Hospitalar , Antibacterianos , Estudos de Coortes , Farmacorresistência Bacteriana , Humanos , Estudos Retrospectivos , Staphylococcus aureus , Ucrânia
12.
Pol J Microbiol ; 68(4): 403-415, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31880885

RESUMO

Urinary tract infections (UTIs) belong to the most common community-acquired and nosocomial infections. A main etiological factor of UTIs is uropathogenic Escherichia coli (UPEC). This review describes the current state of knowledge on the resistance of UPEC to antibiotics recommended for the treatment of UTIs based on the available literature data. Nitrofurantoin and fosfomycin are recommended as first-line therapy in the treatment of uncomplicated cystitis, and the resistance to these antimicrobial agents remains low between UPEC. Recently, in many countries, the increasing resistance is observed to trimethoprim-sulfamethoxazole, which is widely used as the first-line antimicrobial in the treatment of uncomplicated UTIs. In European countries, the resistance of UPEC to this antimicrobial agent ranges from 14.6% to 60%. The widespread use of fluoroquinolones (FQs), especially ciprofloxacin, in the outpatients is the cause of a continuous increase in resistance to these drugs. The resistance of UPEC to FQs is significantly higher in developing countries (55.5-85.5%) than in developed countries (5.1-32.0%). Amoxicillin-clavulanic acid is recommended as first line-therapy for pyelonephritis or complicated UTI. Resistance rates of UPEC to amoxicillin-clavulanic acid are regionally variable. In European countries the level of resistance to this antimicrobial ranges from 5.3% (Germany) to 37.6% (France). Increasing rates of UPEC resistance to antimicrobials indicate that careful monitoring of their use for UTI treatment is necessary.Urinary tract infections (UTIs) belong to the most common community-acquired and nosocomial infections. A main etiological factor of UTIs is uropathogenic Escherichia coli (UPEC). This review describes the current state of knowledge on the resistance of UPEC to antibiotics recommended for the treatment of UTIs based on the available literature data. Nitrofurantoin and fosfomycin are recommended as first-line therapy in the treatment of uncomplicated cystitis, and the resistance to these antimicrobial agents remains low between UPEC. Recently, in many countries, the increasing resistance is observed to trimethoprim-sulfamethoxazole, which is widely used as the first-line antimicrobial in the treatment of uncomplicated UTIs. In European countries, the resistance of UPEC to this antimicrobial agent ranges from 14.6% to 60%. The widespread use of fluoroquinolones (FQs), especially ciprofloxacin, in the outpatients is the cause of a continuous increase in resistance to these drugs. The resistance of UPEC to FQs is significantly higher in developing countries (55.5­85.5%) than in developed countries (5.1­32.0%). Amoxicillin-clavulanic acid is recommended as first line-therapy for pyelonephritis or complicated UTI. Resistance rates of UPEC to amoxicillin-clavulanic acid are regionally variable. In European countries the level of resistance to this antimicrobial ranges from 5.3% (Germany) to 37.6% (France). Increasing rates of UPEC resistance to antimicrobials indicate that careful monitoring of their use for UTI treatment is necessary.


Assuntos
Farmacorresistência Bacteriana , Infecções por Escherichia coli/microbiologia , Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Humanos , Escherichia coli Uropatogênica/genética , Escherichia coli Uropatogênica/isolamento & purificação , Escherichia coli Uropatogênica/metabolismo
13.
Pol J Microbiol ; 68(4): 417-427, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31880886

RESUMO

Colistin is a member of cationic polypeptide antibiotics known as polymyxins. It is widely used in animal husbandry, plant cultivation, animal and human medicine and is increasingly used as one of the last available treatment options for patients with severe infections with carbapenem-resistant Gram-negative bacilli. Due to the increased use of colistin in treating infections caused by multidrug-resistant (MDR) bacteria, the resistance to this antibiotic ought to be monitored. Bacterial resistance to colistin may be encoded on transposable genetic elements (e.g. plasmids with the mcr genes). Thus far, nine variants of the mcr gene, mcr-1 - mcr-9, have been identified. Chromosomal resistance to colistin is associated with the modification of lipopolysaccharide (LPS). Various methods, from classical microbiology to molecular biology methods, are used to detect the colistin-resistant bacterial strains and to identify resistance mechanisms. The broth dilution method is recommended for susceptibility testing of bacteria to colistin.Colistin is a member of cationic polypeptide antibiotics known as polymyxins. It is widely used in animal husbandry, plant cultivation, animal and human medicine and is increasingly used as one of the last available treatment options for patients with severe infections with carbapenem-resistant Gram-negative bacilli. Due to the increased use of colistin in treating infections caused by multidrug-resistant (MDR) bacteria, the resistance to this antibiotic ought to be monitored. Bacterial resistance to colistin may be encoded on transposable genetic elements (e.g. plasmids with the mcr genes). Thus far, nine variants of the mcr gene, mcr-1 ­ mcr-9, have been identified. Chromosomal resistance to colistin is associated with the modification of lipopolysaccharide (LPS). Various methods, from classical microbiology to molecular biology methods, are used to detect the colistin-resistant bacterial strains and to identify resistance mechanisms. The broth dilution method is recommended for susceptibility testing of bacteria to colistin.


Assuntos
Antibacterianos/farmacologia , Infecções Bacterianas/microbiologia , Colistina/farmacologia , Farmacorresistência Bacteriana , Gammaproteobacteria/efeitos dos fármacos , Animais , Infecções Bacterianas/tratamento farmacológico , Gammaproteobacteria/genética , Gammaproteobacteria/metabolismo , Humanos
14.
Pol J Microbiol ; 68(4): 477-491, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31880892

RESUMO

This study explored a potential treatment against methicillin-resistant Staphylococcus aureus (MRSA) infections that combines thioridazine (TZ), an efflux pump inhibitor, and miconazole (MCZ), an autolysis inducer, with the anti-microbial drug cloxacillin (CXN). In vitro, the combination treatment of TZ and MCZ significantly reduced 4096-fold (Σ (FIC) = 0.1 - 1.25) the MIC value of CXN against S. aureus. In vivo, the combination therapy significantly relieved breast redness and swelling in mice infected with either clinical or standard strains of S. aureus. Meanwhile, the number of bacteria isolated from the MRSA135-infected mice decreased significantly (p = 0.0427 < 0.05) after the combination therapy when compared to monotherapy. Moreover, the number of bacteria isolated from the mice infected with a reference S. aureus strain also decreased significantly (p = 0.0191 < 0.05) after the combination therapy when compared to monotherapy. The pathological changes were more significant in the CXN-treated group when compared to mice treated with a combination of three drugs. In addition, we found that combination therapy reduced the release of the bacteria-stimulated cytokines such as IL-6, IFN-γ, and TNF-α. Cytokine assays in serum revealed that CXN alone induced IL-6, IFN-γ, and TNF-α in the mouse groups infected with ATCC 29213 or MRSA135, and the combination of these three drugs significantly reduced IL-6, IFN-γ, and TNF-α concentrations. Also, the levels of TNF-α and IFN-γ in mice treated with a combination of three drugs were significantly lower than in the CXN-treated group. Given the synergistic antibacterial activity of CXN, we concluded that the combination of CXN with TZ, and MCZ could be developed as a novel therapeutic strategy against S. aureus.This study explored a potential treatment against methicillin-resistant Staphylococcus aureus (MRSA) infections that combines thioridazine (TZ), an efflux pump inhibitor, and miconazole (MCZ), an autolysis inducer, with the anti-microbial drug cloxacillin (CXN). In vitro, the combination treatment of TZ and MCZ significantly reduced 4096-fold (Σ (FIC) = 0.1 ­ 1.25) the MIC value of CXN against S. aureus. In vivo, the combination therapy significantly relieved breast redness and swelling in mice infected with either clinical or standard strains of S. aureus. Meanwhile, the number of bacteria isolated from the MRSA135-infected mice decreased significantly (p = 0.0427 < 0.05) after the combination therapy when compared to monotherapy. Moreover, the number of bacteria isolated from the mice infected with a reference S. aureus strain also decreased significantly (p = 0.0191 < 0.05) after the combination therapy when compared to monotherapy. The pathological changes were more significant in the CXN-treated group when compared to mice treated with a combination of three drugs. In addition, we found that combination therapy reduced the release of the bacteria-stimulated cytokines such as IL-6, IFN-γ, and TNF-α. Cytokine assays in serum revealed that CXN alone induced IL-6, IFN-γ, and TNF-α in the mouse groups infected with ATCC 29213 or MRSA135, and the combination of these three drugs significantly reduced IL-6, IFN-γ, and TNF-α concentrations. Also, the levels of TNF-α and IFN-γ in mice treated with a combination of three drugs were significantly lower than in the CXN-treated group. Given the synergistic antibacterial activity of CXN, we concluded that the combination of CXN with TZ, and MCZ could be developed as a novel therapeutic strategy against S. aureus.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Farmacorresistência Bacteriana , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , beta-Lactamas/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Bacteriólise/efeitos dos fármacos , Cloxacilina/farmacologia , Quimioterapia Combinada , Humanos , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Miconazol/farmacologia , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/citologia , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo , Tioridazina/farmacologia
15.
Pol J Microbiol ; 68(4): 541-548, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31880897

RESUMO

Analysis of the epidemiology of Staphylococcus aureus (SA) ocular infections and virulence factors of the isolates with a special emphasis on their drug resistance, and the ability of biofilm formation. In a period from 2009 to 2013, 83 isolates of SA were prospectively collected and preserved in a multicenter laboratory-based study carried out in southern Poland. Epidemiological, phenotypic, and genotypic analyses were performed. The resistance and virulence genes were analyzed. Screening for the biofilm formation was provided. Among the materials derived from ocular infections from 456 patients, SA was found in 18.2% (n = 83) of cases (one SA isolate per one patient). Most infections were identified in the age group of over 65 years (OR 8.4 95%CI; 1.03-68.49). The majority of patients (73.4%) were hospitalized. Among the virulence and resistance genes, the most frequently detected were the lukE (72.2%, n = 60) and ermA (15.6%, n = 13) genes. A positive result of the CRA test (the ability of biofilm formation) was found in 66.2% (n = 55) of isolates. Among the strains under study, 6.0% (n = 5) had the methicillin-resistant Staphylococcus aureus phenotype, and 26.5% (n = 22) had the macrolide-lincosamide-streptogramin B phenotype. In 48 (57.8%) isolates the neomycin resistance was revealed. All isolates under study were sensitive to vancomycin. The population most susceptible to ocular SA infections consists of hospitalized patients aged 65 and more. The SA strains under study showed the increased ability to biofilm formation. In the strains tested, high susceptibility to chloramphenicol and fluoroquinolones was demonstrated. However, the high level of drug resistance to neomycin detected in this study among SA isolates and the blood-ocular barrier makes it difficult to treat ocular infections.Analysis of the epidemiology of Staphylococcus aureus (SA) ocular infections and virulence factors of the isolates with a special emphasis on their drug resistance, and the ability of biofilm formation. In a period from 2009 to 2013, 83 isolates of SA were prospectively collected and preserved in a multicenter laboratory-based study carried out in southern Poland. Epidemiological, phenotypic, and genotypic analyses were performed. The resistance and virulence genes were analyzed. Screening for the biofilm formation was provided. Among the materials derived from ocular infections from 456 patients, SA was found in 18.2% (n = 83) of cases (one SA isolate per one patient). Most infections were identified in the age group of over 65 years (OR 8.4 95%CI; 1.03-68.49). The majority of patients (73.4%) were hospitalized. Among the virulence and resistance genes, the most frequently detected were the lukE (72.2%, n = 60) and ermA (15.6%, n = 13) genes. A positive result of the CRA test (the ability of biofilm formation) was found in 66.2% (n = 55) of isolates. Among the strains under study, 6.0% (n = 5) had the methicillin-resistant Staphylococcus aureus phenotype, and 26.5% (n = 22) had the macrolide-lincosamide-streptogramin B phenotype. In 48 (57.8%) isolates the neomycin resistance was revealed. All isolates under study were sensitive to vancomycin. The population most susceptible to ocular SA infections consists of hospitalized patients aged 65 and more. The SA strains under study showed the increased ability to biofilm formation. In the strains tested, high susceptibility to chloramphenicol and fluoroquinolones was demonstrated. However, the high level of drug resistance to neomycin detected in this study among SA isolates and the blood-ocular barrier makes it difficult to treat ocular infections.


Assuntos
Proteínas de Bactérias/genética , Farmacorresistência Bacteriana , Infecções Oculares/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Fatores de Virulência/genética , Adolescente , Adulto , Idoso , Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Criança , Infecções Oculares/epidemiologia , Feminino , Humanos , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Polônia/epidemiologia , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/classificação , Staphylococcus aureus/metabolismo , Fatores de Virulência/metabolismo , Adulto Jovem
16.
Yi Chuan ; 41(12): 1138-1147, 2019 Dec 20.
Artigo em Chinês | MEDLINE | ID: mdl-31857285

RESUMO

Pathogenic Escherichia coli (E. coli) is the most common pathogen causing urinary tract infection in animals. We investigated the antibiotic resistance and virulence genes of pathogenic E. coli CCHTP derived from urine with occult blood of the giant panda by whole genome sequencing. The flanking sequencing of resistance and virulence genes in genomic islands were also analyzed. Our results demonstrate that E. coli CCHTP contains different families of antibiotic resistance genes, most of which are efflux pump related genes, including multiple drug resistance efflux pump genes mdfA, emrE, and mdtN. A total of 166 virulence factors and 563 virulence genes were identified, and the most virulence factors and related genes are involved in host cell attachment and invasion processes. Furthermore, sequence analysis of 19 genomic islands revealed that antibiotic and virulence genes are associated with mobile genetic elements (transposon and insertion sequence) in GIs011 and GIs017. These structures can mediate horizontal transfer of antibiotic and virulence genes. Our work described the distribution of antibiotic resistance genes and virulence genes in E. coli CCHTP, which may provide an important guidance for treatment and rational drug use of E. coli CCHTP infection in the giant panda.


Assuntos
Farmacorresistência Bacteriana , Proteínas de Escherichia coli , Escherichia coli , Urina , Ursidae , Animais , Farmacorresistência Bacteriana/genética , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Genoma Bacteriano , Urina/microbiologia , Ursidae/microbiologia , Virulência/genética , Fatores de Virulência/genética , Sequenciamento Completo do Genoma
20.
Zhonghua Shao Shang Za Zhi ; 35(11): 798-803, 2019 Nov 20.
Artigo em Chinês | MEDLINE | ID: mdl-31775468

RESUMO

Objective: To explore the resistance mechanism and gene type of carbapenems-resistant Klebsiella pneumoniae (CRKP) in burn care unit. Methods: A total of 27 CRKP strains were primarily isolated from 22 patients [20 males, 2 females, aged (42±16) years] admitted to burn care unit of Institute of Burn Research of the First Affiliated Hospital of Army Medical University (the Third Military Medical University, hereinafter referred to as our department) from January to December 2017. After identification of bacteria, the months of detection and distribution of sample source were analyzed. Drug resistance tests of 15 antibiotics were conducted. Polymerase chain reaction was used to detect the drug resistant genes. Pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST) were used to analyze the gene type of strains. Results: (1) During the whole year of 2017, CRKP strains were mostly detected in August (8 strains), September (6 strains), and October (5 strains), with no CRKP in January, March, June, November, and December. Five strains from bed units were detected in August (2 strains), September (1 strain), and October (2 strains). (2) Twenty-seven CRKP strains were derived from blood samples (40.7%, 11/27), wound exudate samples (18.5%, 5/27), deep vein catheter samples (11.1%, 3/27), sputum samples (7.4%, 2/27), urine samples (3.7%, 1/27), and bed unit samples (18.5%, 5/27). (3) The 27 CRKP strains were detected with drug-resistance rates of 100.0% to 7 antibiotics including cefoperazone/sulbactam, piperacillin/tazobactam, cefazolin, ceftriaxone, cefepime, ertapenem, and compound sulfamethoxazole, no drug-resistance to tigecycline, with drug-resistance rates higher than 81.0% to the rest 7 antibiotics. (4) Detection rates for resistance gene bla(CTX-M-10), bla(SHV), bla(TEM), bla(CTX-M-14), bla(ACT), and bla(KPC) were all above 92.5%. (5) According to PFGE, the 27 CRKP strains had 6 types (A, A(1), A(2), B, C, and D). Strains of type A were mainly detected in February, May, and September, with detection rate of 37.0% (10/27). Strains of type C were mainly detected in July, August, and October, with detection rate of 48.1% (13/27). Strains of types A(1), A(2), B, and D were scatteredly detected, with detection rate of 3.7% (1/27) respectively. According to MLST, the 27 CRKP strains had 6 STs. ST11 was the most frequent type, accounting for 74.1% (20/27), which was detected in August to October. The detection rate of ST395, ST2230, ST215, ST260, and STnew ranged from 3.7%(1/27) to 7.4%(2/27), and the strains were scatteredly detected. Conclusions: The main source of CRKP from burn care unit of our department was bloodstream. All the CRKP strains showed high drug-resistance rate and complicated resistance mechanism. There were small scale outbreaks caused by CRKP of type A, type C, and ST11, which should be paid more attention to in clinical treatment and infection control.


Assuntos
Queimaduras/microbiologia , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/efeitos dos fármacos , Adulto , Antibacterianos/farmacologia , Unidades de Queimados , Feminino , Humanos , Klebsiella pneumoniae/classificação , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , beta-Lactamases/genética
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