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1.
J Hazard Mater ; 416: 125847, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492800

RESUMO

Microplastics (MPs) and antibiotic resistance genes (ARGs) are two classes of emerging and prevalent contaminants in terrestrial environments. To date, effects of MPs on the occurrence of ARGs in terrestrial invertebrates remain uncertain. Here we exposed earthworms to a soil amended with polystyrene MPs at two environmentally relevant concentrations to elucidate the occurrence and mechanisms of ARGs in earthworms impacted by MPs with different sizes. Nano-size and 10 mg/kg of 100 µm MPs slightly affected the occurrence of ARGs in earthworms. Highest abundance of ARGs was found in the presence of 10 mg/kg of 10 µm MPs, whereas 100 mg/kg of 10 µm MPs significantly changed the profile of ARGs. Metagenomics sequencing and toxicity tests indicated that MPs caused toxicity and influenced the abundance of microbial community in earthworms, resulting in the changes of ARGs. Results of proteomics and metabolomics demonstrated that 100 mg/kg of 10 µm MPs changed the microenvironment of earthworm gut, built a new homeostatic process, and thus increased the abundance of key bacterial that carried a variety of ARGs. This study highlights the size-dependent toxic effects of MPs and their impacts on the transfer of ARGs in terrestrial environments.


Assuntos
Microplásticos , Oligoquetos , Animais , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos , Genes Bacterianos , Oligoquetos/genética , Plásticos , Poliestirenos , Solo
2.
J Hazard Mater ; 416: 125865, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492813

RESUMO

Anaerobic biological treatment technologies are one of the major hotspots of antibiotic resistance genes (ARGs). Previous studies have applied the electrochemical process to improve biogas production, however, it was challenged that high voltages might promote membrane permeability and reactive oxygen species overproduction to promote ARGs proliferation. Herein, the biogas production and ARGs proliferation in an anaerobic electrochemical membrane bioreactor (AnEMBR) were investigated at the gradient voltages of 0-0.9 V. Results show the reactor performances (average CH4 production and current generation) were distinctly improved with the increase of applied voltage, and reached the optimum at 0.9 V. However, long-term application (>30 day) of 0.9 V deteriorated the reactor performances. Meanwhile, the relative abundances of most target ARGs in the supernatant and effluent of AnEMBR at 0.9 V increased by 0.68-1.55 and 0.42-1.26 logs compared to those before applying voltage, respectively. After disconnecting the circuit, these ARGs abundances all decreased to the original level. Significant correlations between intlI and ARGs (e.g., tetA, tetQ, sulI, and sulII) were observed, indicating horizontal gene transfer may contribute to the increased ARGs. Moreover, the shift of microbial communities caused by the applied voltage enriched potential ARGs-hosts (e.g., Tolumonas), contributing to the proliferation of ARGs.


Assuntos
Antibacterianos , Biocombustíveis , Anaerobiose , Antibacterianos/farmacologia , Reatores Biológicos , Proliferação de Células , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos
3.
J Hazard Mater ; 416: 125868, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492815

RESUMO

Comprehensive studies on the effects of cold stress on antibiotic resistance genes (ARGs) in the intestines and feces remain scarce. In this study, pigs were selected as the animal model and divided into a normal temperature group and a 48-h short-term cold stress group. The ARG profiles in fecal, cecal content and cecal mucosa samples were analyzed. The results showed that the normalized abundance of ARGs in the cecal mucosa samples in the cold stress group was significantly higher than that in the normal temperature group, while the normalized ARG abundances in the fecal and cecal content samples were significantly lower than those in the normal temperature group (P < 0.05). The bacterial community composition (especially Firmicutes) was the major driver impacting the ARG profile and accounted for 32.2% of the variation in the ARG profile, followed by metabolites (especially creatinine and oxypurinol) and mobile genetic elements (MGEs) (especially plasmids and insertion elements). And it was found that creatinine and oxypurinol can reduce the abundance of ARGs and Firmicutes in the in vitro experiment. The results indicate that short-term cold stress can reduce the abundance of ARGs in the cecum and feces of pigs, providing reference data for environmental safety.


Assuntos
Antibacterianos , Genes Bacterianos , Animais , Antibacterianos/farmacologia , Ceco , Resposta ao Choque Frio , Resistência Microbiana a Medicamentos/genética , Fezes , Suínos
4.
J Hazard Mater ; 416: 126085, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492900

RESUMO

The usage of triclosan (TCS) may rise rapidly due to the COVID-19 pandemic. TCS usually sinks in the activated sludge. However, the effects of TCS in activated sludge remain largely unknown. The changes in nitrogen cycles and the abundances of antibiotic resistance genes (ARGs) caused by TCS were investigated in this study. The addition of 1000 µg/L TCS significantly inhibited nitrification since the ammonia conversion rate and the abundance of nitrification functional genes decreased by 12.14%. The other nitrogen cycle genes involved in nitrogen fixation and denitrification were also suppressed. The microbial community shifted towards tolerance and degradation of phenols. The addition of 100 µg/L TCS remarkably increased the total abundance of ARGs and mobile genetic elements by 33.1%, and notably, the tetracycline and multidrug resistance genes increased by 54.75% and 103.42%, respectively. The co-occurrence network revealed that Flavobacterium might have played a key role in the spread of ARGs. The abundance of this genus increased 92-fold under the addition of 1000 µg/L TCS, indicating that Flavobacterium is potent in the tolerance and degradation of TCS. This work would help to better understand the effects of TCS in activated sludge and provide comprehensive insight into TCS management during the pandemic era.


Assuntos
COVID-19 , Triclosan , Antibacterianos , Resistência Microbiana a Medicamentos/genética , Humanos , Nitrificação , Pandemias , SARS-CoV-2 , Esgotos
5.
J Hazard Mater ; 416: 126136, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492925

RESUMO

Zero valent iron (ZVI) coupled with bioreactors is arising as a promising technology for antibiotic resistance genes (ARGs) mitigation, whereas the succession and behaviors of microbes caused by ZVI in relieving ARGs propagation remain unclear. Herein, the effects of ZVI on microbial quorum sensing (QS), quorum quenching (QQ) system and community dynamics were examined in anaerobic bioreactor fed with oxytetracycline (tet), to illustrate the roles of evolutive microbial communication and community composition in ARGs attenuation. With the addition of 5 g/L ZVI, the total absolute abundance of tet ARGs was retarded by approximate 95% and 72% in sludge and effluent after 25 days operation. The abundance of mobile genetic elements and the heredity of antibiotic resistant bacteria revealed the declined horizontal and vertical transfer of ARGs, which directly led to the reduced ARGs propagation. Potential mechanisms are that the positive effects of ZVI on QQ activity via the functional bacteria enrichment inhibited QS system and thus ARGs transfer. Partial least--squares path modeling further demonstrated that ARGs abundance was strongly limited by the dynamics of bacterial composition and thereby less frequent microbial communication. These results provide new insights into the mechanisms of antibiotic resistome remission in anaerobic bioreactor modified by ZVI.


Assuntos
Antibacterianos , Percepção de Quorum , Anaerobiose , Antibacterianos/farmacologia , Reatores Biológicos , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Ferro , Percepção de Quorum/genética , Esgotos
6.
JNMA J Nepal Med Assoc ; 59(233): 39-41, 2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-34508456

RESUMO

INTRODUCTION: Urinary tract infection is treated by the antibiotic sensitivity pattern of uropathogens in our population. Present infection cases have been showing an increase in resistance to the current first-line of antibiotics. The objective of this study is to determine the resistance of antibiotics in Escherichia coli in a tertiary care center. METHODS: This is a descriptive cross-sectional study done in Kathmandu Medical College Teaching Hospital from October 2018 to February 2019. The sample size was calculated, and convenient sampling was done. Patients with urine culture positive (i.e., Colony-forming unit >105) were included in the study. All positive samples were tested for antibiotics sensitivity and resistance. The resistance to the antibiotics was recorded using Statistical Package for Social Sciences version 20. Point estimate at 95% confidence interval was calculated along with frequency and proportion for binary data. RESULTS: Out of 100 samples, the highest number of organisms isolated was Escherichia coli, 71 (71%). Escherichia coli showed the highest resistance to drugs like Norfloxacin, 37 (52.11%), AmoxicillinClavulanic acid 37 (52.11%), followed by Co-trimoxazole 32 (45.1%), Ceftriaxone, 24 (33.8%), and Ciprofloxacin 23 (32.3%). CONCLUSIONS: Escherichia coli showed the highest resistance to commonly used antibiotics like Norfloxacin, Amoxicillin-Clavulanic acid, Co-trimoxazole, Ceftriaxone, and Ciprofloxacin.


Assuntos
Antibacterianos , Escherichia coli , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Estudos Transversais , Resistência Microbiana a Medicamentos , Humanos , Testes de Sensibilidade Microbiana , Nepal/epidemiologia , Centros de Atenção Terciária
7.
Int J Mol Sci ; 22(16)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34445592

RESUMO

The Hfq protein is a bacterial RNA chaperone, involved in many molecular interactions, including control of actions of various small RNA regulatory molecules. We found that the presence of Hfq was required for survival of plasmid-containing Escherichia coli cells against high concentrations of chloramphenicol (plasmid p27cmr), tetracycline (pSC101, pBR322) and ampicillin (pBR322), as hfq+ strains were more resistant to these antibiotics than the hfq-null mutant. In striking contrast, production of Hfq resulted in low resistance to high concentrations of kanamycin when the antibiotic-resistance marker was chromosome-borne, with deletion of hfq resulting in increasing bacterial survival. These results were observed both in solid and liquid medium, suggesting that antibiotic resistance is an intrinsic feature of these strains rather than a consequence of adaptation. Despite its major role as RNA chaperone, which also affects mRNA stability, Hfq was not found to significantly affect kan and tet mRNAs turnover. Nevertheless, kan mRNA steady-state levels were higher in the hfq-null mutant compared to the hfq+ strain, suggesting that Hfq can act as a repressor of kan expression.This observation does correlate with the enhanced resistance to high levels of kanamycin observed in the hfq-null mutant. Furthermore, dependency on Hfq for resistance to high doses of tetracycline was found to depend on plasmid copy number, which was only observed when the resistance marker was expressed from a low copy plasmid (pSC101) but not from a medium copy plasmid (pBR322). This suggests that Hfq may influence survival against high doses of antibiotics through mechanisms that remain to be determined. Studies with pBR322Δrom may also suggest an interplay between Hfq and Rom in the regulation of ColE1-like plasmid replication. Results of experiments with a mutant devoid of the part of the hfq gene coding for the C-terminal region of Hfq suggested that this region, as well as the N-terminal region, may be involved in the regulation of expression of antibiotic resistance in E. coli independently.


Assuntos
Antibacterianos/farmacologia , Cromossomos Bacterianos/genética , Resistência Microbiana a Medicamentos/genética , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Fator Proteico 1 do Hospedeiro/genética , Mutação , Plasmídeos/genética , Escherichia coli/efeitos dos fármacos
8.
Environ Pollut ; 286: 117560, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34438490

RESUMO

As a common natural phenomenon, corpse decomposition may lead to serious environmental pollution such as nitrogen pollution. However, less is known about antibiotic resistance genes (ARGs), an emerging contaminant, during corpse degradation. Here, ARGs and microbiome in three soil types (black, red and yellow soil) have been investigated between experimental and control groups based on next-generation sequencing and high-throughput quantitative PCR techniques. We found that the absolute abundance of total ARGs and mobile genetic elements (MGEs) in the experimental groups were respectively enriched 536.96 and 240.60 times in different soil types, and the number of ARGs in experimental groups was 7-25 more than that in control groups. For experimental groups, the distribution of ARGs was distinct in different soil types, but sulfonamide resistance genes were always enriched. Corpse decomposition was a primary determinant for ARGs profiles. Microbiome, NH4+ concentrates and pH also significantly affected ARGs profiles. Nevertheless, soil types had few effects on ARGs. For soil microbiome, some genera were elevated in experimental groups such as the Ignatzschineria and Myroides. The alpha diversity is decreased in experimental groups and microbial community structures are different between treatments. Additionally, the Escherichia and Neisseria were potential pathogens elevated in experimental groups. Network analysis indicated that most of ARGs like sulfonamide and multidrug resistance genes presented strong positively correlations with NH4+ concentrates and pH, and some genera like Ignatzschineria and Dysgonomonas were positively correlated with several ARGs such as aminoglycoside and sulfonamide resistance genes. Our study reveals a law of ARGs' enrichment markedly during corpse decomposing in different soil types, and these ARGs contaminant maintaining in environment may pose a potential threat to environmental safety and human health.


Assuntos
Antibacterianos , Solo , Animais , Antibacterianos/farmacologia , Cadáver , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Humanos , Microbiologia do Solo
9.
Sci Total Environ ; 791: 148423, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34412390

RESUMO

Water systems in Southeast Asia accumulate antibiotics and antibiotic resistance genes (ARGs) from multiple origins, notably including human clinics and animal farms. To ascertain the fate of antibiotics and ARGs in natural water environments, we monitored the concentrations of these items in Thailand. Here, we show high concentrations of tetracyclines (72,156.9 ng/L) and lincomycin (23,968.0 ng/L) in pig farms, followed by nalidixic acid in city canals. The city canals and rivers contained diverse distributions of antibiotics and ARGs. Assessments of targeted ARGs, including sul1, sul2, sul3, and tet(M), showed that freshwater (pig farm wastewater, rivers, and canals) consistently contained these ARGs, but these genes were less abundant in seawater. Although sulfonamides were low concentrations (<170 ng/mL), sul1 and sul2 genes were abundant in freshwater (minimum 4.4 × 10-3-maximum 1.0 × 100 copies/16S), suggesting that sul genes have disseminated over a long period, despite cessation of use of this class of antibiotics. Ubiquitous distribution of sul genes in freshwater appeared to be independent of selection pressure. In contrast, water of the coastal sea in the monitored area was not contaminated by these antibiotics or ARGs. The density of Enterobacteriales was lower in seawater than in freshwater, suggesting that the number of ARG-possessing Enterobacteriales falls after entering seawater. From the pig farms, through rivers/canals, to the coastal sea, the occurrence of tetracyclines and tet(M) exhibited some correlation, although not a strong one. However, no correlations were found between concentrations of total antibiotics and ARGs, nor between sulfonamides and sul genes. This is the first comprehensive study showing Thai features of antibiotics and ARGs contaminations. The pig farm is hot spot of antibiotics and ARGs, and sul genes ubiquitously distribute in freshwater environments, which become less abundant in seawater.


Assuntos
Rios , Águas Residuárias , Animais , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos , Suínos , Tailândia
10.
J Environ Sci (China) ; 107: 150-159, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34412778

RESUMO

The black soldier fly larvae (BSFL) have been successfully applied to treat various organic wastes. However, the impacts of heavy metals on antibiotic resistance in the BSFL guts are poorly understood. Here, we investigated the effect of copper (exposure concentrations of 0, 100 and 800 mg/kg) on the antibiotic and metal resistance profiles in BSFL guts. A total of 83 antibiotic resistance genes (ARGs), 18 mobile genetic elements (MGEs) and 6 metal resistance genes (MRGs) were observed in larval gut samples. Exposure to Cu remarkably reduced the diversity of ARGs and MGEs, but significantly enhanced the abundances of gut-associated ARGs and MRGs. The levels of MRGs copA, czcA and pbrT were dramatically strengthened after Cu exposure as compared with CK (increased by 2.8-13.5 times). Genera Enterococcus acted as the most predominant potential host of multiple ARG, MGE and MRG subtypes. Meanwhile, high exposure to Cu aggravated the enrichment of potential pathogens in BSFL guts, especially for Escherichia, Enterococcus and Salmonella species. The mantel test and procrustes analysis revealed that the gut microbial communities could be a key determinant for antibiotic and metal resistance. However, no significant positive links were observed between MGEs and ARGs or MRGs, possibly suggesting that MGEs did not play a crucial role in shaping the ARGs or MRGs in BSFL guts under the stress of Cu. These findings extend our understanding on the impact of heavy metals on the gut-associated antibiotic and metal resistome of BSFL.


Assuntos
Dípteros , Metais Pesados , Animais , Cobre/toxicidade , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Incidência , Larva , Metais Pesados/toxicidade
11.
Huan Jing Ke Xue ; 42(9): 4358-4365, 2021 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-34414734

RESUMO

Wastewater from antibiotic production usually contains a huge amount of antibiotic resistance genes (ARG). Therefore, it is essential to study the dissemination and control of antibiotic resistance during the treatment of antibiotic production wastewater. The mutual influence between microbial community evolution, wastewater characteristics, and ARG was investigated using high-throughput sequencing and a variety of statistical analysis methods. Results showed that the influent characteristics had only a marginal influence on the microbial community of each treatment section. Methanogenic bacteria and sulfate-reducing bacteria were the dominant microbes in the anaerobic and anoxic tank. Chemical oxygen demand (COD), NO2--N, and PO43--P exhibited an intimate relationship with the microbial community, whereas biomass, NH4+-N, and COD showed a strong correlation with ARG and mobile genetic elements (MGE). In the sludge, more genera (including pathogenic bacteria) were significantly correlated with ARG and MGE than that in the wastewater, indicating that bacteria in the sludge had a greater chance of acquiring pathogenicity and resistance. Therefore, more attnetion should be given to waste sludge from the treatment plants of antibiotic production wastewater. This research could provide further understanding of antibiotic resistance dissemination and control during wastewater treatment, especially for antibiotic production wastewater.


Assuntos
Microbiota , Espiramicina , Purificação da Água , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos/genética , Águas Residuárias
12.
ACS Infect Dis ; 7(9): 2604-2611, 2021 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-34355905

RESUMO

The rifamycins are broad-spectrum antibiotics that are primarily utilized to treat infections caused by mycobacteria, including tuberculosis. Interestingly, various species of bacteria are known to contain an enzyme called Arr that catalyzes ADP-ribosylation of rifamycin antibiotics as a mechanism of resistance. Here, we study Arr modulation in relevant Gram-positive and -negative species. We show that a C-terminal truncation of Arr (ArrC), encoded in the genome of Mycobacterium smegmatis, activates Arr-mediated rifamycin modification. Through structural comparisons of mycobacterial Arr and human poly(ADP-ribose) polymerases (PARPs), we identify a known small molecule PARP inhibitor that can act as an adjuvant to sensitize M. smegmatis to the rifamycin antibiotic rifampin via inhibition of Arr, even in the presence of ArrC. Finally, we demonstrate that this rifampin/adjuvant combination treatment is effective at inhibiting growth of the multidrug-resistant (MDR) nontuberculosis pathogen Mycobacterium abscessus, which has become a growing cause of human infections in the clinic.


Assuntos
Mycobacterium , Rifamicinas , ADP Ribose Transferases , Resistência Microbiana a Medicamentos , Humanos , Testes de Sensibilidade Microbiana , Mycobacterium/genética , Rifamicinas/farmacologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-34444052

RESUMO

Antibiotic resistance (AR) in the environment is of great global concern and a threat to public health. Soil bacteria, including Bacillus spp., could act as recipients and reservoirs of AR genes of clinical, livestock, or agricultural origin. These genes can be shared between bacteria, some of which could be potentially human pathogens. This process can be favored in conditions of abiotic stress, such as heavy metal contamination. The Almadén mining district (Ciudad Real, Spain) is one of the environments with the highest mercury (Hg) contamination worldwide. The link between heavy metal contamination and increased AR in environmental bacteria seems clear, due to co-resistance and co-selection phenomena. In the present study, 53 strains were isolated from rhizospheric and bulk soil samples in Almadén. AR was tested using Vitek® 2 and minimum inhibitory concentration (MIC) values were obtained and interpreted based on the criteria of the Clinical and Laboratory Standards Institute (CLSI) guidelines. Based on the resistance profiles, five different antibiotypes were established. The Hg minimum bactericidal concentration (MBC) of each strain was obtained using the plating method with increasing concentrations of HgCl2. A total of 72% of Bacillus spp. showed resistance to two or more commonly used antibiotics. A total of 38 isolates expressed AR to cephalosporins. Finally, the environmental co-selection of AR to cephalosporins and tetracyclines by selective pressure of Hg has been statistically demonstrated.


Assuntos
Bacillus , Mercúrio , Bacillus/genética , Resistência Microbiana a Medicamentos , Humanos , Mercúrio/análise , Mineração , Solo
14.
Molecules ; 26(16)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34443481

RESUMO

This study explores the capability of Sulfate Radical-based Advanced Oxidation Processes (SR-AOPs) for the simultaneous disinfection and decontamination of urban wastewater. Sulfate and hydroxyl radicals in solution were generated activating peroxymonosulfate (PMS) under UV-C irradiation at pilot plant scale. The efficiency of the process was assessed toward the removal of three CECs (Trimethoprim (TMP), Sulfamethoxazole (SMX), and Diclofenac (DCF)) and three bacteria (Escherichia coli, Enterococcus spp., and Pseudomonas spp.) in actual urban wastewater (UWW), obtaining the optimal value of PMS at 0.5 mmol/L. Under such experimental conditions, bacterial concentration ≤ 10 CFU/100 mL was reached after 15 min of UV-C treatment (0.03 kJ/L of accumulative UV-C radiation) for natural occurring bacteria, no bacterial regrowth was observed after 24 and 48 h, and 80% removal of total CECs was achieved after 12 min (0.03 kJ/L), with a release of sulfate ions far from the limit established in wastewater discharge. Moreover, the inactivation of Ampicillin (AMP), Ciprofloxacin (CPX), and Trimethoprim (TMP) antibiotic-resistant bacteria (ARB) and reduction of target genes (ARGs) were successfully achieved. Finally, a harmful effect toward the receiving aquatic environment was not observed according to Aliivibrio fischeri toxicity tests, while a slightly toxic effect toward plant growth (phytotoxicity tests) was detected. As a conclusion, a cost analysis demonstrated that the process could be feasible and a promising alternative to successfully address wastewater reuse challenges.


Assuntos
Peróxidos/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Purificação da Água/métodos , Aliivibrio fischeri/efeitos dos fármacos , Antibacterianos/química , Bactérias/efeitos dos fármacos , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Resistência Microbiana a Medicamentos/genética , Oxirredução , Plantas/efeitos dos fármacos , Sulfatos/química , Raios Ultravioleta , Águas Residuárias/análise , Águas Residuárias/microbiologia , Águas Residuárias/toxicidade , Poluentes Químicos da Água/efeitos da radiação
15.
Front Cell Infect Microbiol ; 11: 683464, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34422678

RESUMO

Background: Clostridioides difficile (C. difficile) is one of the primary pathogens responsible for infectious diarrhea. Antibiotic treatment failure, occurring in about 30% of patients, and elevated rates of antibiotic resistance pose a major challenge for therapy. Reinfection often occurs by isolates that produce biofilm, a protective barrier impermeable to antibiotics. We explored the association between antibiotic resistance (in planktonic form) and biofilm-production in 123 C. difficile clinical isolates. Results: Overall, 66 (53.6%) out of 123 isolates produced a biofilm, with most of them being either a strong (44%) or moderate (34.8%) biofilm producers. When compared to susceptible isolates, a statistically higher percentage of isolates with reduced susceptibility to metronidazole or vancomycin were biofilm producers (p < 0.0001, for both antibiotics). Biofilm production intensity was higher among tolerant isolates; 53.1% of the metronidazole-susceptible isolates were not able to produce biofilms, and only 12.5% were strong biofilm-producers. In contrast, 63% of the isolates with reduced susceptibility had a strong biofilm-production capability, while 22.2% were non-producers. Among the vancomycin-susceptible isolates, 51% were unable to produce biofilms, while all the isolates with reduced vancomycin susceptibility were biofilm-producers. Additionally, strong biofilm production capacity was more common among the isolates with reduced vancomycin susceptibility, compared to susceptible isolates (72.7% vs. 18.8%, respectively). The distribution of biofilm capacity groups was statistically different between different Sequence-types (ST) strains (p =0.001). For example, while most of ST2 (66.7%), ST13 (60%), ST42 (80%) isolates were non-producers, most (75%) ST6 isolates were moderate producers and most of ST104 (57.1%) were strong producers. Conclusions: Our results suggest an association between reduced antibiotic susceptibility and biofilm production capacity. This finding reinforces the importance of antibiotic susceptibility testing, mainly in recurrence infections that may be induced by a strain that is both antibiotic tolerant and biofilm producer. Better adjustment of treatment in such cases may reduce recurrences rates and complications. The link of biofilm production and ST should be further validated; if ST can indicate on isolate virulence, then in the future, when strain typing methods will be more available to laboratories, ST determination may aid in indecision between supportive vs. aggressive treatment.


Assuntos
Clostridioides difficile , Clostridioides , Biofilmes , Resistência Microbiana a Medicamentos , Humanos , Testes de Sensibilidade Microbiana
16.
Sci Transl Med ; 13(606)2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34380772

RESUMO

Vaccines against bacterial pathogens can protect recipients from becoming infected with potentially antibiotic-resistant pathogens. However, by altering the selective balance between antibiotic-sensitive and antibiotic-resistant bacterial strains, vaccines may also suppress-or spread-antibiotic resistance among unvaccinated individuals. Predicting the outcome of vaccination requires knowing what drives selection for drug-resistant bacterial pathogens and what maintains the circulation of both antibiotic-sensitive and antibiotic-resistant strains of bacteria. To address this question, we used mathematical modeling and data from 2007 on penicillin consumption and penicillin nonsusceptibility in Streptococcus pneumoniae (pneumococcus) invasive isolates from 27 European countries. We show that the frequency of penicillin resistance in S. pneumoniae can be explained by between-host diversity in antibiotic use, heritable diversity in pneumococcal carriage duration, or frequency-dependent selection brought about by within-host competition between antibiotic-resistant and antibiotic-sensitive S. pneumoniae strains. We used our calibrated models to predict the impact of non-serotype-specific pneumococcal vaccination upon the prevalence of S. pneumoniae carriage, incidence of disease, and frequency of S. pneumoniae antibiotic resistance. We found that the relative strength and directionality of competition between drug-resistant and drug-sensitive pneumococcal strains was the most important determinant of whether vaccination would promote, inhibit, or have little effect upon the evolution of antibiotic resistance. Last, we show that country-specific differences in pathogen transmission substantially altered the predicted impact of vaccination, highlighting that policies for managing antibiotic resistance with vaccines must be tailored to a specific pathogen and setting.


Assuntos
Infecções Pneumocócicas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana , Resistência Microbiana a Medicamentos , Humanos , Testes de Sensibilidade Microbiana , Nasofaringe , Infecções Pneumocócicas/tratamento farmacológico , Infecções Pneumocócicas/prevenção & controle , Streptococcus pneumoniae , Vacinação
17.
Medicine (Baltimore) ; 100(32): e26913, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34397929

RESUMO

ABSTRACT: To investigate the factors affecting the duration of vancomycin-resistant enterococci (VRE) colonization in stroke patients.A total of 52 stroke patients with VRE colonization were enrolled. We divided the groups into several factors and confirmed whether each factor affected VRE colonization. Independent t test, bivariate correlation analysis, and Cox proportional hazards model were used to confirm statistical significance.Among 52 patients, 28 were ischemic stroke and 24 were hemorrhagic stroke. The mean duration of the VRE colonization was 39.08 ±â€Š44.22 days. The mean duration of VRE colonization of the ischemic stroke patients was 25.57 ±â€Š30.23 days and the hemorrhagic stroke patients was 54.83 ±â€Š52.75 days. The mean intensive care unit (ICU) care period was 15.23 ±â€Š21.98 days. Independent sample t test showed the hemorrhagic stroke (P < .05), use of antibiotics (P < .01), oral feeding (P < .01) were associated with duration of VRE colonization. Bivariate correlation analysis showed duration of ICU care (P < .001) was associated with duration of VRE colonization. Cox proportional hazard model showed oral feeding (P = .001), use of antibiotics (P = .003), and duration of ICU care (P = .001) as independent factors of duration of VRE colonization.Careful attention should be given to oral feeding, duration of ICU care, and use of antibiotics in stroke patients, especially hemorrhagic stroke patients, for intensive rehabilitation at the appropriate time.


Assuntos
Antibacterianos/uso terapêutico , Resistência Microbiana a Medicamentos , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Unidades de Terapia Intensiva , Acidente Vascular Cerebral/complicações , Enterococos Resistentes à Vancomicina/isolamento & purificação , Idoso , Feminino , Seguimentos , Infecções por Bactérias Gram-Positivas/complicações , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Masculino , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
18.
Bioresour Technol ; 340: 125668, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34339999

RESUMO

This study evaluated the effects of biocontrol Bacillus and fermenting bacteria addition on the microbial community, metabolic functions and antibiotic resistance genes (ARGs) of new prickly ash seed oil meal (PSOM)-biochar composting. The results showed that the addition of Bacillus subtilis and fermentation bacteria significantly increased the NH4+-N, bacterial abundance and fungal diversity of compost while decreasing the relative abundances (RAs) of carbon metabolism genes in mature compost. NH4+-N was significantly correlated with microbial abundance and diversity, and its increase was closely related to microbial amino acid metabolism. The addition of biocontrol and fermenting bacteria changed the RAs of ARGs, which was caused by changes in the potential hosts Proteobacteria, Bacteroidota and Firmicutes in the compost. Consequently, adding Bacillus and fermenting bacteria into PSOM to make composting was suggested as an effective method to promote nutrient transformation, regulate microbial activity and decrease RAs of tetracycline and vancomycin ARGs.


Assuntos
Bacillus , Compostagem , Microbiota , Antibacterianos/farmacologia , Bacillus/genética , Bacillus subtilis , Carvão Vegetal , Resistência Microbiana a Medicamentos , Fermentação , Genes Bacterianos , Esterco , Óleos Vegetais
19.
Bull World Health Organ ; 99(8): 548-549, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34354309
20.
Water Res ; 203: 117507, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34392041

RESUMO

In recent years, karst water has been polluted by emerging pollutants such as antibiotics. In this study, the bacterial communities and antibiotic resistance genes (ARGs) in antibiotics contaminated karst river was studied in summer and winter. The concentration of antibiotics in winter karst river is higher than that in summer, and there are significant differences in structure of bacterial community and ARGs between karst river water samples. Aminoglycoside, beta-lactamase and multidrug are the main types of ARGs, and transposons play an important role in the spread of ARGs. The horizontal gene transfer (HGT) of ARGs between bacteria mediated by mobile genetic elements (MGEs) would cause the spread of ARGs and bring potential ecological risks. In addition, we found that the risk of antibiotic resistant pathogenic bacteria (ARPB) in winter was possibly higher than that in summer. It was suggested that the discharge of antibiotics, water amount and seasonal occurrence time of human intestinal diseases affect the risks caused by antibiotics contaminants. This study helps us to understand the transmission mechanism of ARGs and their potential seasonal ecological risks in complex karst water systems.


Assuntos
Antibacterianos , Rios , Antibacterianos/farmacologia , Bactérias/genética , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Humanos
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