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1.
Plant Dis ; 108(2): 278-285, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37743587

RESUMO

The fungal pathogen Botrytis cinerea is a notorious problem on many floriculture greenhouse hosts including petunia, geranium, and poinsettia; these key crops contribute to the $6.43 billion U.S. ornamental industry. While growers use cultural strategies to reduce relative humidity and free moisture to limit Botrytis blight, fungicides remain a primary component of control programs. Isolates (n = 386) of B. cinerea sampled from symptomatic petunia, geranium, and poinsettia in Michigan greenhouses from 2018 to 2021 were screened for resistance to eight fungicides belonging to seven Fungicide Resistance Action Committee (FRAC) groups. Single-spored isolates were subjected to a germination-based assay using previously defined discriminatory doses of each fungicide. Resistance was detected to thiophanate-methyl (FRAC 1; 94%), pyraclostrobin (FRAC 11; 80%), boscalid (FRAC 7; 67%), iprodione (FRAC 2; 65%), fenhexamid (FRAC 17; 38%), cyprodinil (FRAC 9; 38%), fludioxonil (FRAC 12; 21%), and fluopyram (FRAC 7; 13%). Most isolates (63.5%) were resistant to at least four FRAC groups, with 8.7% of all isolates demonstrating resistance to all seven FRAC groups tested. Resistance frequencies for each fungicide were similar among crops, production regions, and growing cycles but varied significantly for each greenhouse. Phenotypic diversity was high, as indicated by the 48 different fungicide resistance profiles observed. High frequencies of resistance to multiple fungicides in B. cinerea populations from floriculture hosts highlight the importance of sustainable and alternative disease management practices for greenhouse growers.


Assuntos
Fragaria , Fungicidas Industriais , Fungicidas Industriais/farmacologia , Botrytis , Farmacorresistência Fúngica , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Fragaria/microbiologia
2.
Sensors (Basel) ; 24(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38475225

RESUMO

In this study, we explore how the strategic positioning of conductive yarns influences the performance of plated knit strain sensors fabricated using commercial knitting machines with both conductive and non-conductive yarns. Our study reveals that sensors with conductive yarns located at the rear, referred to as 'purl plated sensors', exhibit superior performance in comparison to those with conductive yarns at the front, or 'knit plated sensors'. Specifically, purl plated sensors demonstrate a higher sensitivity, evidenced by a gauge factor ranging from 3 to 18, and a minimized strain delay, indicated by a 1% strain in their electromechanical response. To elucidate the mechanisms behind these observations, we developed an equivalent circuit model. This model examines the role of contact resistance within varying yarn configurations on the sensors' sensitivity, highlighting the critical influence of contact resistance in conductive yarns subjected to wale-wise stretching on sensor responsiveness. Furthermore, our findings illustrate that the purl plated sensors benefit from the vertical movement of non-conductive yarns, which promotes enhanced contact between adjacent conductive yarns, thereby improving both the stability and sensitivity of the sensors. The practicality of these sensors is confirmed through bending cycle tests with an in situ monitoring system, showcasing the purl plated sensors' exceptional reproducibility, with a standard deviation of 0.015 across 1000 cycles, and their superior sensitivity, making them ideal for wearable devices designed for real-time joint movement monitoring. This research highlights the critical importance of conductive yarn placement in sensor efficacy, providing valuable guidance for crafting advanced textile-based strain sensors.

3.
Int J Mol Sci ; 25(10)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38791501

RESUMO

Sepsis is a life-threatening syndrome triggered by infection and accompanied by high mortality, with antimicrobial resistances (AMRs) further escalating clinical challenges. The rapid and reliable detection of causative pathogens and AMRs are key factors for fast and appropriate treatment, in order to improve outcomes in septic patients. However, current sepsis diagnostics based on blood culture is limited by low sensitivity and specificity while current molecular approaches fail to enter clinical routine. Therefore, we developed a suppression PCR-based selective enrichment sequencing approach (SUPSETS), providing a molecular method combining multiplex suppression PCR with Nanopore sequencing to identify most common sepsis-causative pathogens and AMRs using plasma cell-free DNA. Applying only 1 mL of plasma, we targeted eight pathogens across three kingdoms and ten AMRs in a proof-of-concept study. SUPSETS was successfully tested in an experimental research study on the first ten clinical samples and revealed comparable results to clinical metagenomics while clearly outperforming blood culture. Several clinically relevant AMRs could be additionally detected. Furthermore, SUPSETS provided first pathogen and AMR-specific sequencing reads within minutes of starting sequencing, thereby potentially decreasing time-to-results to 11-13 h and suggesting diagnostic potential in sepsis.


Assuntos
Ácidos Nucleicos Livres , Sepse , Humanos , Sepse/diagnóstico , Sepse/microbiologia , Sepse/sangue , Ácidos Nucleicos Livres/sangue , Farmacorresistência Bacteriana/genética , Hemocultura/métodos , DNA Bacteriano/genética , Reação em Cadeia da Polimerase Multiplex/métodos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias/genética , Bactérias/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Sequenciamento por Nanoporos/métodos
4.
Int J Mol Sci ; 24(12)2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37372935

RESUMO

Antimicrobial peptides (AMPs) represent a promising class of therapeutic biomolecules that show antimicrobial activity against a broad range of microorganisms, including life-threatening pathogens. In contrast to classic AMPs with membrane-disrupting activities, new peptides with a specific anti-biofilm effect are gaining in importance since biofilms could be the most important way of life, especially for pathogens, as the interaction with host tissues is crucial for the full development of their virulence in the event of infection. Therefore, in a previous study, two synthetic dimeric derivatives (parallel Dimer 1 and antiparallel Dimer 2) of the AMP Cm-p5 showed specific inhibition of the formation of Candida auris biofilms. Here we show that these derivatives are also dose-dependently effective against de novo biofilms that are formed by the widespread pathogenic yeasts C. albicans and C. parapsilosis. Moreover, the activity of the peptides was demonstrated even against two fluconazole-resistant strains of C. auris.


Assuntos
Candida albicans , Fluconazol , Fluconazol/farmacologia , Candida parapsilosis , Antifúngicos/farmacologia , Candida , Biofilmes , Peptídeos/farmacologia , Testes de Sensibilidade Microbiana
5.
Prep Biochem Biotechnol ; : 1-9, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38010621

RESUMO

Membrane photobioreactors (MPBRs) have gained significant attention due to their ability to support microalgae activities such as cultivation, harvesting, and production of beneficial products. Despite various efforts to mitigate membrane fouling, a fundamental issue in membrane processes, in these systems, a cost-effective and less energy-consuming method is still needed. This study examines the impact of the cross-sectional area of the riser and the baffle material on membrane fouling in an internal loop airlift MPBR. The use of hydrophilic polyester-polypropylene (PES-PP) baffles proves to be more effective than plexiglass baffles. Specifically, in configurations with d = 0.7 cm and d = 1.4 cm, RC/RT decreased by approximately 20% and 13%, respectively, compared to plexiglass baffles. As for the values of RP/RT at a distance of d = 0.7, nearly a 5% increase was observed, and at a distance of d = 1.4, an increase of approximately 11% was observed. This is due to the development of the cake layer on the matrix structure of the PES-PP baffles instead of the membrane itself. The most optimal outcomes were reached while working with PES-PP at a distance of 0.7 cm, as it prolonged the membrane fouling time to 46 h.

6.
Virologie (Montrouge) ; 27(4): 225-337, 2023 08 01.
Artigo em Francês | MEDLINE | ID: mdl-37565678

RESUMO

Resistance to viruses is an important aspect of plant breeding. One way to achieve it is to select genetic resistances based on the susceptibility factors hijacked by the virus to infect the plants. Here, we recount work done on genes encoding translation initiation factors eIF4E, some of the most successful targets for obtaining resistance to potyviruses, starting from their characterization 20 years ago. With examples from different plant species, pepper, tomato, tobacco and arabidopsis, we present the basis of this type of resistances and their characteristics, highlighting the role of gene redundancy among 4E factors, their specificity for the virus and the need for the plant of a trade-off between resistance and development. Finally, we show how the new genome editing techniques could be used in plant breeding to develop eIF4E-based resistances in crops, mimicking the functional alleles that have been selected during evolution in many crops.


Assuntos
Resistência à Doença , Fator de Iniciação 4E em Eucariotos , Doenças das Plantas , Plantas , Potyvirus , Alelos , Fator de Iniciação 4E em Eucariotos/genética , Melhoramento Vegetal , Potyvirus/genética , Plantas/virologia , Doenças das Plantas/virologia
7.
Potato Res ; 66(1): 231-244, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35996391

RESUMO

Virus infection is the key constraint to potato cultivation worldwide. Especially, coinfection by multiple viruses could exacerbate the yield loss. Transgenic plants expressing artificial microRNAs (amiRNAs) have been shown to confer specific resistance to viruses. In this study, three amiRNAs containing Arabidopsis miR159 as a backbone, expressing genes targeting P25, HC-Pro and Brp1 of potato virus X (PVX), potato virus Y (PVY) and potato spindle tuber viroid (PSTVd), were constructed. amiR-159P25, amiR-159HCPro and amiR-159Brp1 were cloned into the plant expression vector pCAMBIA1301 with a CaMV35S promoter, producing the p1301-pre-amiRP25-HCPro-Brp1 vector. Twenty-three transgenic plants (Solanum tuberosum cv. 'Youjin') were obtained by Agrobacterium tumefaciens-mediated transformation, and ten PCR-positive transplants were chosen for further analysis. Quantitative real-time PCR results indicated that 10 transgenic plants could express amiRNAs successfully. Southern blotting hybridization proved that amiR-159P25-HCPro-Brp1 had integrated into potato genome in transgenic lines. Viral (viroid) challenge assays revealed that these transgenic plants demonstrated resistance against PVX, PVY and PSTVd coinfection simultaneously, whereas the untransformed controls developed severe symptoms. This study demonstrates a novel amiRNA-based mechanism that may have the potential to develop multiple viral resistance strategies in potato.

8.
Antimicrob Agents Chemother ; 66(9): e0089222, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-35969073

RESUMO

In this study, we characterize a new collection that comprises multidrug-resistant (MDR), extensively drug-resistant (XDR), pandrug-resistant (PDR), and carbapenem-resistant modern clinical isolates of Acinetobacter baumannii collected from hospitals through national microbiological surveillance in Belgium. Bacterial isolates (n = 43) were subjected to whole-genome sequencing (WGS), combining Illumina (MiSeq) and Nanopore (MinION) technologies, from which high-quality genomes (chromosome and plasmids) were de novo assembled. Antimicrobial susceptibility testing was performed along with genome analyses, which identified intrinsic and acquired resistance determinants along with their genetic environments and vehicles. Furthermore, the bacterial isolates were compared to the most prevalent A. baumannii sequence type 2 (ST2) (Pasteur scheme) genomes available from the BIGSdb database. Of the 43 strains, 40 carried determinants of resistance to carbapenems; blaOXA-23 (n = 29) was the most abundant acquired antimicrobial resistance gene, with 39 isolates encoding at least two different types of OXA enzymes. According to the Pasteur scheme, the majority of the isolates were globally disseminated clones of ST2 (n = 25), while less frequent sequence types included ST636 (n = 6), ST1 (n = 4), ST85 and ST78 (n = 2 each), and ST604, ST215, ST158, and ST10 (n = 1 each). Using the Oxford typing scheme, we identified 22 STs, including two novel types (ST2454 and ST2455). While the majority (26/29) of blaOXA-23 genes were chromosomally carried, all blaOXA-72 genes were plasmid borne. Our results show the presence of high-risk clones of A. baumannii within Belgian health care facilities with frequent occurrences of genes encoding carbapenemases, highlighting the crucial need for constant surveillance.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Infecções por Acinetobacter/microbiologia , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Genômica , Humanos , Proteína 1 Semelhante a Receptor de Interleucina-1/genética , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , beta-Lactamases/genética
9.
Small ; 18(48): e2204926, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36260824

RESUMO

Chemo-phototherapy has emerged as a promising approach to complement traditional cancer treatment and enhance therapeutic effects. However, it still faces the challenges of drug efflux transporter-mediated chemoresistance and heat shock proteins (HSPs)-mediated phototherapy tolerance, which both depend on an excessive supply of adenosine triphosphate. Therefore, manipulating energy metabolism to impair the expression or function of P-glycoprotein (P-gp) and HSPs may be a prospective strategy to reverse cancer therapeutic resistance. Herein, a chondroitin sulfate (CS)-functionalized zeolitic imidazolate framework-8 (ZIF-8) chemo-phototherapy nanoplatform (CS/ZIF-8@A780/DOX NPs) is rationally designed that is capable of manipulating energy metabolism against cancer therapeutic resistance by integrating the photosensitizer IR780 iodide (IR780)-conjugated atovaquone (ATO) (A780) and the chemotherapeutic agent doxorubicin (DOX). Mechanistically, ATO and zinc ions that are released in the acidic tumor microenvironment can lead to systematic energy exhaustion through disturbing mitochondrial electron transport and the glycolysis process, thus suppressing the activity of P-gp and HSP70, respectively. In addition, CS is used on the surface of ZIF-8@A780/DOX NPs to improve the targeting capability to tumor tissues. These data provide an efficient strategy for manipulating energy metabolism for cancer treatment, especially for overcoming cancer chemo-phototherapy resistance.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Zeolitas , Humanos , Fototerapia , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Metabolismo Energético , Nanopartículas/uso terapêutico , Microambiente Tumoral
10.
Small ; 18(9): e2105896, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34913586

RESUMO

The poor chemical miscibility between metal and organic materials usually leads to both structural and energetic mismatches at gold/organic interfaces, and thereby, high contact resistance of organic electronic devices. This study shows that the contact resistance of organic field-effect transistors is significantly reduced by one order of magnitude, by reforming the contact interface between gold electrodes and conjugated polymers upon a polymer insulator-assisted thermal annealing. Upon an optimized solution process, the conjugated polymer is homogenously distributed within the amorphous polymer insulator matrix with relatively low glass transition temperature, and thus, even a moderate annealing temperature can induce sufficient motion of conjugated polymer chains to simultaneously adjust the polymer orientation and improve the packing of gold atoms. Consequently, gold/conjugated polymer contact is reorganized after annealing, which improves both charge transport from bulk gold to interface and charge injection from gold into conjugated polymers. This method, with appropriate insulator matrix, is effective for improving the injection of both holes and electrons, and widely applicable for many unipolar and ambipolar conjugated polymers to optimize the device performance and simultaneously increase the optical transparency (over 80%). A frequency doubler and a phase modulator are demonstrated, respectively, using the ambipolar transistors with optimized charge injection properties.

11.
Plasmid ; 122: 102638, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35691511

RESUMO

Plasmids are widely involved in the dissemination of characteristics within bacterial communities. Their genomic content can be assessed by high-throughput sequencing of the whole plasmid fraction of an environment, the plasmidome. In this study, we analyzed the plasmidome of a biofilm formed in the effluents of the teaching hospital of Clermont-Ferrand (France). Our analysis discovered >350 new complete plasmids, with a length ranging from 1219 to 40,193 bp. Forty-two plasmid incompatibility (Inc) groups were found among all the plasmid contigs. Ten large plasmids, described here in detail, were reconstructed from plasmid contigs, seven of which carried antibiotic resistance genes. Four plasmids potentially confer resistance to numerous families of antibiotics, including carbapenems, aminoglycosides, colistin, and chloramphenicol. Most of these plasmids were affiliated to Proteobacteria, a phylum of Gram-negative bacteria. This study therefore illustrates the composition of an environmental mixed biofilm in terms of plasmids and antibiotic resistance genes.


Assuntos
Antibacterianos , Biofilmes , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos , Hospitais , Plasmídeos/genética
12.
Graefes Arch Clin Exp Ophthalmol ; 260(12): 3909-3917, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35687174

RESUMO

PURPOSE: Aim of this study was to evaluate the frequencies, trends, and antibiotic resistance of bacteria collected from ocular surface or contact lens material in a German tertiary referral center from 2009 to 2019. METHODS: Microbiological data from 2009 to 2019 was analyzed. Culture-dependent microbial identification and analysis of antibiotic sensitivity was completed by the Institute of Microbiology. Statistical analysis of age- and sex-specific differences as well as changes in the microbial spectrum and resistance over the study period was performed with GraphPad Prism 9.0 applying nonparametric tests (level of significance: p ≦ 0.05). RESULTS: A total of 6361 specimens were analyzed. Positivity rate was 18.6%. Sixty-three percent (n = 680) of the bacterial isolates were derived from ocular surface and 37% (n = 399) from contact lens material. The ratio of gram-negative bacteria was significantly higher in contact lens material. Multiresistant bacteria showed a significant increase with patient age (p < 0.0001). An overall increase in resistance to levofloxacin (p = 0.0239) was detected. Only 2.4% and 3.1% isolates were resistant to a combination of moxifloxacin and gentamicin, respectively, levofloxacin and gentamicin. CONCLUSIONS: The reported bacterial spectrum is similar to comparable centers. Our data show that it should not be assumed that the newest classes of antibiotics have the best efficacy or lowest resistance levels. In suspected bacterial conjunctivitis, we propose using gentamicin as first-line therapy. In therapy refractive cases and in involvement of the cornea, we recommend a combination of gentamicin and ofloxacin or moxifloxacin. Overall, the evaluated organisms showed good sensitivity to the regularly used antibiotics.


Assuntos
Infecções Oculares Bacterianas , Levofloxacino , Masculino , Feminino , Humanos , Moxifloxacina , Testes de Sensibilidade Microbiana , Infecções Oculares Bacterianas/tratamento farmacológico , Infecções Oculares Bacterianas/epidemiologia , Infecções Oculares Bacterianas/microbiologia , Centros de Atenção Terciária , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias , Gentamicinas , Estudos Retrospectivos , Farmacorresistência Bacteriana
13.
J Dairy Res ; : 1-8, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36177856

RESUMO

This study was designed to show the changes in glycolmacropeptides (GMPs) of whey protein solution (WPS) due to different pretreatments before and after ultrafiltration (UF). The combined form of two variants (A&B) of GMPs is a helpful compound for nutritional management of phenylketonuria and ulcerative-colitis diseases and has low content of phenylalanine (Phe). WPS with 10% concentration was prepared, acidified (adjusted to pH = 3.0), and passed through a PES (polyethersulfone) membrane in the 1st-stage of ultrafiltration (UF-1). Then the resulting permeate was neutralized and went through the 2nd-stage of ultrafiltration (UF-2) under similar conditions. Four experiments of TRT-CON, CON-TRT, TRT-TRT, and CON-CON were used with different pretreatments, where TRT was a mixing-treatment of 30 min at 150 RPM applied either after acidification of WPS or after neutralization of first permeate and before UF-2 process. While the concentration and purity of the combined GMPs in UF-2 retentate in TRT-TRT respectively were >95.6 and 99.5%, its Phe became <10 ppm among the experiments. Highly glycolyzed polymers of GMPs (MW = 45-50 kDa) were formed in the TRT-TRT experiment and went through the pore sizes of PES membrane of UF-1 easily because of their flexible structure. However, they remained in the UF-2 retentate, due to to the formation of bulky polymers. The TRT-TRT experiment had the highest reversible and irreversible resistances for passing through the UF-1 and remaining on the UF-2 membranes, and its fouling index was significantly less than other experiments.

14.
Mol Pharm ; 18(9): 3532-3543, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34323492

RESUMO

Conjugation of antibiotics with polymers is an emerging strategy to improve the performance of these important drugs. Here, the antibiotic ciprofloxacin (CIP) was conjugated with amphiphilic poly(2-oxazoline) (POx) block copolymers to investigate whether the activity of the antibiotic was enhanced due to additionally induced membrane activity. The resulting polymer-antibiotic conjugates (PACs) are an order of magnitude more active against the bacterial strain Staphylococcus aureus than CIP and show high activities against numerous pathogenic bacterial strains. Their high activity depends on an optimal hydrophobic/hydrophilic balance (HHB) of the POx tail. Mechanistic studies revealed that the derivatization of CIP required for the polymer conjugation lowers the affinity of the antibiotic to its target topoisomerase IV. However, the amphiphilic PACs are most likely concentrated within the bacterial cytoplasm, which overcompensates the loss of affinity and results in high antibacterial activity. In addition, the development of resistance in S. aureus and Escherichia coli is slowed down. More importantly, the amphiphilic PACs are active against CIP-resistant S. aureus and E. coli. The PACs with the highest activity are not cytotoxic toward human stem cells and do not lyse blood cells in saturated solution.


Assuntos
Antibacterianos/farmacologia , Ciprofloxacina/farmacologia , Escherichia coli/efeitos dos fármacos , Oxazóis/química , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Células Cultivadas , Ciprofloxacina/química , Composição de Medicamentos/métodos , Farmacorresistência Bacteriana , Excipientes/química , Humanos , Células-Tronco Mesenquimais , Testes de Sensibilidade Microbiana
15.
Arch Microbiol ; 203(1): 183-191, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32803345

RESUMO

In this study, the presence of plasmids responsible for carbohydrate fermentation and antibiotic resistance and the stability of these plasmids in artificial gastric juice were investigated in 20 Lactobacillus plantarum strains with probiotic properties. Plasmid curing was performed with novobiocin, acriflavine and elevated incubation temperature to identify plasmids encoded with carbohydrate fermentation and antibiotic resistance genes and to compare them with artificial gastric juice. Plasmid profiling of the strains revealed that 100% of the strains were harbouring plasmids in varying sizes and numbers. The plasmid number of the potential probiotic strains ranged between 1 and 4, and the plasmid size ranged between 5.779 and 16.138 kb. The potential probiotic strains could not survive in the artificial gastric juice at pH 2.0. Although the strains maintained their viability in an artificial gastric juice at pH 2.5 and 3.0, and their derivatives lost their plasmids at a high rate (100%). Similarly, high levels of cured derivatives were obtained with 8 µg/mL novobiocin and 100 µg/mL acriflavine applications, and 24 h incubation at 43 °C. All the experiments were also performed to compare with two L. plantarum-type strains containing plasmids responsible for tetracycline and tetracycline + erythromycin resistances. Artificial gastric juice and other plasmid curing treatments caused a high-frequency loss in the antibiotic resistances of type strains. Determining plasmid stability in artificial gastric juice is a novel approach. Plasmid stability in the gastrointestinal tract is important for maintaining the plasmid-encoded probiotic properties.


Assuntos
Acriflavina/farmacologia , Farmacorresistência Bacteriana/genética , Suco Gástrico/microbiologia , Lactobacillus plantarum/efeitos dos fármacos , Novobiocina/farmacologia , Antibacterianos/farmacologia , Fermentação , Suco Gástrico/efeitos dos fármacos , Temperatura Alta , Lactobacillus plantarum/genética , Plasmídeos/genética , Probióticos , Resistência a Tetraciclina/genética
16.
Ann Clin Microbiol Antimicrob ; 20(1): 60, 2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34481499

RESUMO

BACKGROUND: Blood stream infections (BSI) caused by Extended Spectrum Beta-Lactamases (ESBLs) producing Enterobacteriaceae is a clinical challenge leading to high mortality, especially in developing countries. In this study, we sought to describe the epidemiology of ESBL-producing Escherichia coli strains isolated from Vietnamese individuals with BSI, to investigate the concordance of genotypic-phenotypic resistance, and clinical outcome of ESBL E. coli BSI. METHODS: A total of 459 hospitalized patients with BSI were screened between October 2014 and May 2016. 115 E. coli strains from 115 BSI patients were isolated and tested for antibiotic resistance using the VITEK®2 system. The ESBL phenotype was determined by double disk diffusion method following the guideline of Clinical and Laboratory Standards Institute. Screening for beta-lactamase (ESBL and carbapenemase) genes was performed using a multiplex-PCR assay. RESULTS: 58% (67/115) of the E. coli strains were ESBL-producers and all were susceptible to both imipenem and meropenem. Resistance to third-generation cephalosporin was common, 70% (81/115) were cefotaxime-resistant and 45% (52/115) were ceftazidime-resistant. blaCTX-M was the most common ESBL gene detected (70%; 80/115) The sensitivity and specificity of blaCTX-M-detection to predict the ESBL phenotype was 87% (76-93% 95% CI) and 54% (39-48% 95% CI), respectively. 28%% (22/80) of blaCTX-M were classified as non-ESBL producers by phenotypic testing for ESBL production. The detection of blaCTX-M in ESBL-negative E. coli BSI was associated with fatal clinical outcome (27%; 6/22 versus 8%; 2/26, p = 0.07). CONCLUSION: A high prevalence of ESBL-producing E. coli isolates harbouring blaCTX-M was observed in BSI patients in Vietnam. The genotypic detection of blaCTX-M may have added benefit in optimizing and guiding empirical antibiotic therapy of E. coli BSI to improve clinical outcome.


Assuntos
Bacteriemia/tratamento farmacológico , Resistência às Cefalosporinas/genética , Proteínas de Escherichia coli/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , beta-Lactamases/genética , Bacteriemia/microbiologia , Escherichia coli/isolamento & purificação , Humanos , Fenótipo , Sepse , Vietnã/epidemiologia , Sequenciamento Completo do Genoma
17.
Int Microbiol ; 23(2): 171-177, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31218538

RESUMO

Presence of extended-spectrum ß-lactamase (ESBL-E), AmpC-producing and carbapenemase-producing (CPE) Enterobacteriaceae has been observed not only in the clinical environment, but also in the out-of-hospital environment. The objective of this study was to isolate and characterize strains of ESBL, AmpC, and CPE present in feces of healthy carriers in Navarra (n = 125). Despite the fact that no CPE strains were isolated, 16% and 11.2% of the studied population were ESBL-E and AmpC carriers, respectively. No significant differences were found by gender or age; young people (5-18 years old) showed the highest ESBL-E prevalence (31.8%). The isolates corresponded to E. coli (57.1%), Enterobacter spp. (28.6%), and Citrobacter freundii (14.3%), and all strains showed multidrug-resistant profiles. High resistance against cephalosporins, penicillins, and monobactams, and sensitivity to carbapenems, quinolones, and aminoglycosides were observed. With respect to ESBL producers, 52.4% were CTX-M-type (19.0% CTX-M-14, 9.5% CTX-M-1, and 28.6% CTX-M-15) and 47.6% were TEM-type (38.1% TEM-171). These results confirm the extensive dissemination of these resistances among a healthy population and pose the need to implement control measures and strategies according to the One Health approach in order to prevent the increase of severe and untreatable infections in a not far future.


Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Enterobacteriaceae , Fezes/microbiologia , beta-Lactamases/genética , Adolescente , Adulto , Idoso , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Cefalosporinas/farmacologia , Criança , Pré-Escolar , Citrobacter freundii/efeitos dos fármacos , Citrobacter freundii/isolamento & purificação , Citrobacter freundii/metabolismo , Enterobacter/efeitos dos fármacos , Enterobacter/isolamento & purificação , Enterobacter/metabolismo , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Enterobacteriaceae/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Escherichia coli/metabolismo , Feminino , Voluntários Saudáveis , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Monobactamas/farmacologia , Tipagem de Sequências Multilocus , Penicilinas/farmacologia , Prevalência , Adulto Jovem
18.
Artigo em Alemão | MEDLINE | ID: mdl-32410054

RESUMO

Currently, it is becoming alarmingly clear that pharmaceutical companies are continuously withdrawing from antibiotics research and that there is now a market failure. The future decline in the gross domestic product alone is now estimated in the trillions of US dollars. The predicted number of people who could die in 30 years from resistant germs is an urgent call for action. This paper aims to examine the situation on the basis of possible forms of organization and with the help of individual ideas of the principal-agent approach, a theory from economics that can be used to analyze problems between the principal and agent. The result demonstrates the urgent need for action by the state. The longer the alarming proportions of this development is not fully taken into account in the political decision-making process, the more drastic state measures and fewer available options for action there will be at a later point in time.


Assuntos
Antibacterianos , Descoberta de Drogas , Marketing , Motivação , Indústria Farmacêutica , Previsões , Alemanha , Fatores de Tempo
19.
Catheter Cardiovasc Interv ; 94(5): 677-683, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30838771

RESUMO

AIMS: Several invasive techniques are available in clinical practice to assess coronary flow. Nevertheless, the test-retest repeatability of these techniques in a controlled setting has not been reported. Therefore, we sought to evaluate fractional flow reserve (FFR), coronary flow reserve (CFR), index of microvascular resistance (IMR), and absolute coronary blood flow (ABF) with absolute microvascular resistance (AMR) test-retest repeatability using a coronary flow simulator. METHODS AND RESULTS: Using a coronary flow simulator (FFR WetLab version 2.0; Abbott Vascular, Santa Clara, CA), we created stenoses ranging from 0% to 70%, with 10% increments. Three different flows were established with their hyperemic phases, and two consecutive measurements were obtained, evaluating the following indices: FFR, CFR, IMR, ABF, and AMR, using a pressure/temperature wire and an infusion catheter. One hundred and thirty-eight pairs of measurements were performed. Test-retest reliability was compared in 48 FFR, 18 CFR, 24 IMR, 24 ABF, and 24 AMR. Test-retest repeatability showed excellent reproducibility for FFR, ABF, and AMR; respectively 0.98 (0.97-0.99), 0.92 (0.81-0.97) and 0.91 (0.79-0.96) (P < 0.0001 for all). However, test-retest repeatability was weaker for IMR and poor for CFR; respectively 0.53 (0.16-0.77) (P = 0.006) and 0.27 (-0.26-0.67) (P = 0.30). CONCLUSIONS: Using a coronary flow simulator, FFR and ABF with AMR had excellent test-retest reliability. IMR and CFR demonstrated weaker test-retest reliability.


Assuntos
Cateterismo Cardíaco , Estenose Coronária/diagnóstico , Reserva Fracionada de Fluxo Miocárdico , Hemodinâmica , Velocidade do Fluxo Sanguíneo , Estenose Coronária/fisiopatologia , Humanos , Microcirculação , Modelos Cardiovasculares , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Resistência Vascular
20.
Helicobacter ; 24(3): e12584, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30990575

RESUMO

BACKGROUND: Susceptibility-guided treatment has been proposed as a way to improve Helicobacter pylori eradication rates. Evidence on its efficacy for rescue therapy is very scarce. The aim of this study was to indirectly assess the applicability and effectiveness of susceptibility-guided treatment by evaluating (a) the rate of acceptance of endoscopy, (b) its success in detecting resistances, and (c) infection cure rates in patients harboring strains found to be susceptible to the antibiotics administered in clinical trials in which the efficacy of second-line treatments was reported. METHODS: A systematic review of studies evaluating second-line H pylori treatment was carried out in multiple databases. Studies reporting antibiotic susceptibility evaluation and/or cure rates in patients harboring sensitive and resistant strains were selected. Data were extracted in duplicate. RESULTS: The systematic review identified 36 eligible studies. Acceptance was evaluated in only one study of 60 patients, of whom only 38 agreed to endoscopy. Among the 2890 patients who received endoscopy and culture, resistances were finally determined in 86.5%. Cure rate was 72.5% in the 113 patients harboring a clarithromycin-susceptible strain after previous clarithromycin treatment, 93.5% in the 765 patients harboring a metronidazole-susceptible strain, and 83.8% in the 192 patients harboring a levofloxacin-susceptible strain. No studies with repeated administration of levofloxacin or metronidazole were found. CONCLUSION: Even if the culture shows a clarithromycin-sensitive strain, repeating clarithromycin after a first failure should be discouraged. Susceptibility-guided treatment alone did not achieve adequate cure rates for rescue therapies. Additional measures are needed to design rescue treatments that consistently achieve excellent cure rates.


Assuntos
Antibacterianos/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Amoxicilina/uso terapêutico , Claritromicina/uso terapêutico , Endoscopia , Infecções por Helicobacter/microbiologia , Humanos , Levofloxacino/uso terapêutico , Metronidazol/uso terapêutico , Resultado do Tratamento
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