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Folia Microbiologica Feb 2024Wild strains of Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis were tested in an experimental hyperbaric chamber to determine the...
Wild strains of Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis were tested in an experimental hyperbaric chamber to determine the possible effect of hyperbaric oxygen on the susceptibility of these strains to the antibiotics ampicillin, ampicillin + sulbactam, cefazolin, cefuroxime, cefoxitin, gentamicin, sulfamethoxazole + trimethoprim, colistin, oxolinic acid, ofloxacin, tetracycline, and aztreonam during their cultivation at 23 °C and 36.5 °C. Ninety-six-well inoculated microplates with tested antibiotics in Mueller-Hinton broth were cultured under standard incubator conditions (normobaric normoxia) for 24 h or in an experimental hyperbaric chamber (HAUX, Germany) for 24 h at 2.8 ATA of 100% oxygen (hyperbaric hyperoxia). The hyperbaric chamber was pressurised with pure oxygen (100%). Both cultures (normoxic and hyperoxic) were carried out at 23 °C and 36.5 °C to study the possible effect of the cultivation temperature. No significant differences were observed between 23 and 36.5 °C cultivation with or without the 2-h lag phase in Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis. Cultivation in a hyperbaric chamber at 23 °C and 36.5 °C with or without a 2-h lag phase did not produce significant changes in the minimum inhibitory concentration (MIC) of Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis. For the tested strains of Pseudomonas aeruginosa, the possible effect of hyperbaric oxygen on their antibiotic sensitivity could not be detected because the growth of these bacteria was completely inhibited by 100% hyperbaric oxygen at 2.8 ATA under all hyperbaric conditions tested at 23 °C and 36.5 °C. Subsequent tests with wild strains of pseudomonads, burkholderias, and stenotrophomonads not only confirmed the fact that these bacteria stop growing under hyperbaric conditions at a pressure of 2.8 ATA of 100% oxygen but also indicated that inhibition of growth of these bacteria under hyperbaric conditions is reversible.
Topics: Humans; Anti-Bacterial Agents; Hyperbaric Oxygenation; Bacteria, Anaerobic; Oxygen; Bacteria; Pseudomonas aeruginosa; Ampicillin; Escherichia coli; Trimethoprim, Sulfamethoxazole Drug Combination; Klebsiella pneumoniae; Pseudomonas Infections; Oxidative Stress; Microbial Sensitivity Tests; Sulbactam
PubMed: 38100018
DOI: 10.1007/s12223-023-01120-5 -
Scientific Reports Dec 2023Environmental pollution is a global phenomenon and troublesome fact that poses a grave risk to all living entities. Via coupling carbonaceous feedstocks with outstanding...
Environmental pollution is a global phenomenon and troublesome fact that poses a grave risk to all living entities. Via coupling carbonaceous feedstocks with outstanding microbial activity, kinetic experiments were established using the consortium of Proteus mirabilis and Raoultella planticola, biochar-derived sunflower seed husk (SHB) and rice straw (RSB), and their composites, which investigated at 30 °C (150 rpm) to eliminate 700 mg L lead (120 h) and phenol (168 h) from synthetic wastewater. The derived biochars physicochemical properties of were studied. According to adsorption capacity (q), consortium-SHB composites and consortium-RSB composites removed lead completely (70 mg g) within 48 h and 66 h, respectively. Besides, phenol was remediated entirely after 42 h and 48 h by both composite systems (69.90 mg g), respectively, comparing with bacterial consortium only or parent SHB and RSB. Moreover, four kinetic models were studied to describe the bioremediation process. Fractional power and Elovich models could be recommended for describing the adsorption kinetics for lead and phenol removal by the studied biomaterials with high correlation coefficient (R ≥ 0.91 for Pb and ≥ 0.93 for phenol) and lower residual root mean square error (RMSE) and chi-square (X). Overall, bacterial consortium-biochar composites exhibited greater remediation of lead and phenol than the sum of each single bacterial consortium and biochar systems; reflecting synergistic interaction of adsorptive capability of biochar and metabolic performance of bacterial consortium, as denoted by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The current study addressed the successful design of employing functional remediating consortium immobilized on waste biomass-derived biochar as a conducive alternative eco-sorbent and economic platform to detoxify organic and inorganic pollutants.
Topics: Adsorption; Biodegradation, Environmental; Charcoal; Helianthus; Kinetics; Lead; Oryza; Phenol; Phenols; Seeds; Water Pollutants, Chemical; Water Purification
PubMed: 38081934
DOI: 10.1038/s41598-023-49036-x -
Frontiers in Public Health 2023Carbapenem- and extended-spectrum cephalosporin-resistant (CR-E and ESCR-E, respectively) are increasingly isolated worldwide. Information about these bacteria is...
BACKGROUND
Carbapenem- and extended-spectrum cephalosporin-resistant (CR-E and ESCR-E, respectively) are increasingly isolated worldwide. Information about these bacteria is sporadic in Lebanon and generally relies on conventional diagnostic methods, which is detrimental for a country that is struggling with an unprecedented economic crisis and a collapsing public health system. Here, CR-E isolates from different Lebanese hospitals were characterized.
MATERIALS AND METHODS
Non-duplicate clinical ESCR-E or CR-E isolates ( = 188) were collected from three hospitals from June 2019 to December 2020. Isolates were identified by MALDI-TOF, and their antibiotic susceptibility by Kirby-Bauer disk diffusion assay. CR-E isolates ( = 33/188) were further analyzed using Illumina-based WGS to identify resistome, MLST, and plasmid types. Additionally, the genetic relatedness of the CR-E isolates was evaluated using an Infrared Biotyper system and compared to WGS.
RESULTS
Using the Kirby-Bauer disk diffusion assay, only 90 isolates out of the 188 isolates that were collected based on their initial routine susceptibility profile by the three participating hospitals could be confirmed as ESCR-E or CR-E isolates and were included in this study. This collection comprised ( = 70; 77.8%), ( = 13; 14.4%), spp. ( = 6; 6.7%), and ( = 1; 1.1%). While 57 were only ESBL producers the remaining 33 isolates (i.e., 26 , five , one , and one ) were resistant to at least one carbapenem, of which 20 were also ESBL-producers. Among the 33 CR-E, five different carbapenemase determinants were identified: (14/33), (10/33), (5/33), (3/33), and (1/33) genes. Notably, 20 CR-E isolates were also ESBL-producers. The analysis of the genetic relatedness revealed a substantial genetic diversity among CR-E isolates, suggesting evolution and transmission from various sources.
CONCLUSION
This study highlighted the emergence and broad dissemination of and genes in Lebanese clinical settings. The weak AMR awareness in the Lebanese community and the ongoing economic and healthcare challenges have spurred self-medication practices. Our findings highlight an urgent need for transformative approaches to combat antimicrobial resistance in both community and hospital settings.
Topics: Escherichia coli; Lebanon; Multilocus Sequence Typing; Anti-Bacterial Agents; Hospitals; Klebsiella pneumoniae; Carbapenems
PubMed: 38074718
DOI: 10.3389/fpubh.2023.1290912 -
Journal of Clinical Medicine Nov 2023Antimicrobial resistance (AMR) remains a significant public health concern, closely linked to antibiotic overuse. During the COVID-19 pandemic, broad-spectrum...
BACKGROUND
Antimicrobial resistance (AMR) remains a significant public health concern, closely linked to antibiotic overuse. During the COVID-19 pandemic, broad-spectrum antibiotics were frequently administered, potentially exacerbating AMR. This study aimed to assess AMR patterns in our urology department before and after the pandemic.
METHODS
The study encompassed patients admitted to our urology department from January 2016 to December 2022, with confirmed urinary tract infection, bloodstream infection, or wound infection based on positive culture results. Descriptive statistics, including mean, frequency, and percentage, summarized the data. Trends were analyzed using the Joinpoint Regression program.
RESULTS
A total of 506 patients were included. and displayed resistance rates of 65% and 62% to ciprofloxacin, respectively. showed resistance rates of 41% to piperacillin tazobactam and 3rd generation cephalosporins (3GC). Carbapenem resistance was observed in 38% of isolates. Additionally, 26% of , 26% of , and 59% of isolates were ESBL-positive. Among gram+, 72% of isolates were , and 23% of isolates were . Trends in antimicrobial susceptibility patterns over the 7-year study period revealed a statistically significant decrease in resistance to amoxicillin-clavulanic acid (APC: -5.85; C.I. 95% < 0.05) and a statistically significant increase in resistance to 3GC (APC: 9.93; CI (-19.9-14.4 95% < 0.05). There were no statistically significant differences in AMR incidence pre- and post-COVID-19.
CONCLUSION
The COVID-19 pandemic did not appear to influence the AMR incidence in our urology department. However, the overall prevalence of AMR and MDROs in our department remains high compared to European AMR.
PubMed: 38068329
DOI: 10.3390/jcm12237278 -
PloS One 2023The present study aims to investigate the antigenic cross reactivity between the receptor from Proteus mirabilis and spermatozoa against a common sperm immobilization...
An experimental study to decipher the implications of antigenic sharing between Proteus mirabilis and mouse spermatozoa in eliciting an antisperm immune response: A potential culprit in immune infertility.
The present study aims to investigate the antigenic cross reactivity between the receptor from Proteus mirabilis and spermatozoa against a common sperm immobilization factor, SIF, by calorimetric and competitive inhibition studies, and the immunogenicity of this receptor to evoke the formation of antisperm antibodies and their subsequent role in fertility outcome. The sperm binding receptor from Proteus mirabilis (PM-SBR) was extracted from ultrasonicated cell debris by treating it for 12 h at 37°C with 1 M NaCl. After being purified by gel permeation chromatography, its molecular weight as determined by SDS-PAGE was observed to be ≈ 47 kDa. The detrimental impacts of Sperm immobilizing factor (SIF) on spermatozoa viz. motility, viability, and morphology were mitigated when SIF was preincubated with various concentrations of PM-SBR. Using isothermal titration calorimetry, the entropy of the SIF-PM-SBR interaction was found to be -18.31 kJ/mol, whereas the free energy was 28.4 J/mol K. FTIR analysis was used to evaluate the binding interactions between PM-SBR and SIF. In addition, mice that were administered antibodies against PM-SBR were unable to conceive, in contrast to mice that were administered Phosphate buffer saline (PBS) or pre-immunization serum as controls. In light of this, we may conclude that anti-PM-SBR antibodies act as anti-sperm antibodies. Our work found that molecular mimicry between Proteus mirabilis and spermatozoa may cause antisperm immune reactivity. As a result of an immunological response to PM-SBR, infected individuals may produce antibodies against an epitope similar to one found on spermatozoa which helps in developing new strategies for managing autoimmune responses and infertility.
Topics: Male; Animals; Mice; Proteus mirabilis; Semen; Spermatozoa; Infertility; Sperm Motility; Antibodies
PubMed: 38060499
DOI: 10.1371/journal.pone.0289989 -
Poultry Science Feb 2024Chickens in commercial production are hatched in hatcheries without any contact with their parents and colonization of their skin and respiratory tract is therefore...
Chickens in commercial production are hatched in hatcheries without any contact with their parents and colonization of their skin and respiratory tract is therefore dependent on environmental sources only. However, since chickens evolved to be hatched in nests, in this study we evaluated the importance of contact between hens and chicks for the development of chicken skin and tracheal microbiota. Sequencing of PCR amplified V3/V4 variable regions of the 16S rRNA gene showed that contact with adult hens decreased the abundance of E. coli, Proteus mirabilis and Clostridium perfringens both in skin and the trachea, and Acinetobacter johnsonii and Cutibacterium acnes in skin microbiota only. These species were replaced by Lactobacillus gallinarum, Lactobacillus aviarius, Limosilactobacillus reuteri, and Streptococcus pasterianus in the skin and tracheal microbiota of contact chicks. Lactobacilli can be therefore investigated for their probiotic effect in respiratory tract in the future. Skin and respiratory microbiota of contact chickens was also enriched for Phascolarctobacterium, Succinatimonas, Flavonifractor, Blautia, and [Ruminococcus] torque though, since these are strict anaerobes from the intestinal tract, it is likely that only DNA from nonviable cells was detected for these taxa.
Topics: Animals; Female; Chickens; RNA, Ribosomal, 16S; Escherichia coli; Microbiota; Respiratory System
PubMed: 38052128
DOI: 10.1016/j.psj.2023.103302 -
BMC Microbiology Nov 2023The fecal carriage of extended-spectrum β-lactamase-producing Enterobacterales (ESBL-PE) is a major driver of the global spread of these antibiotic resistance...
BACKGROUND
The fecal carriage of extended-spectrum β-lactamase-producing Enterobacterales (ESBL-PE) is a major driver of the global spread of these antibiotic resistance determinants. Here we determined the rate of fecal ESBL-PE carriage in pediatric hospitals and community-serving healthcare centers serving adults and children in the Gaza Strip, Palestine.
METHODS
A total of 373 fecal and rectal samples were collected from different hospitals and clinics in Gaza. The antibiotic susceptibility was determined using the disk diffusion method and interpreted according to CLSI guidelines. The bacterial isolates were tested for ESBL production using phenotypic methods (double disk synergy test and growth on selective chromogenic media). Bla, bla, and bla genes were sought by PCR.
RESULTS
Out of the 373 isolates tested, 138 (37%) were considered ESBL positive as revealed by phenotypic tests. The prevalence of ESBLs among hospitalized patients was 39.1% (hospital setting) whereas, among outpatients attending community healthcare centers, it was 35.1% (community setting). ESBL production among Escherichia coli, Klebsiella pneumoniae, Citrobacter freundii, Proteus mirabilis, and Klebsiella aerogenes isolates was 52.8%, 39.1%, 26.7%, 2.8%, and 2.1% respectively. Meropenem and amikacin were the most effective antibiotics against ESBL producers (68.9% and 73.6% susceptibility, respectively), while only 15.2%, 22.5%, and 24.6% remained susceptible to ceftazidime, cefotaxime, and ceftriaxone, respectively. Out of 138 phenotypically ESBL-positive isolates, 98 randomly chosen were screened for bla, bla, and bla genes. The prevalence rate of bla was 45.9%, while bla and bla genes were detected in 16.8% and 5.2% of CTX-M-negative isolates (corresponding mostly for K. pneumoniae isolates in the case of SHV-PCR), respectively.
CONCLUSIONS
The study revealed an alarmingly high prevalence of fecal carriage of ESBL-producing Enterobacterales among hospitalized children but also in the community of the Gaza Strip. In addition, 30% of ESBL-producers were already resistant to carbapenems, the treatment of choice of infections with ESBL-producers.
Topics: Child; Adult; Humans; beta-Lactamases; Escherichia coli; Hospitals; Klebsiella pneumoniae; Anti-Bacterial Agents; Middle East; Microbial Sensitivity Tests
PubMed: 38036965
DOI: 10.1186/s12866-023-03102-6 -
Germs Mar 2023Infections caused by multidrug-resistant (MDR) bacteria, extended spectrum β-lactamase (ESBL), metallo-β-lactamase (MBL) and AmpC-β-lactamase (AmpC-βL)-producers are...
Enterobacteriaceae isolates from clinical and household tap water samples: antibiotic resistance, screening for extended-spectrum, metallo- and ampC-beta-lactamases, and detection of and in Uyo, Nigeria.
INTRODUCTION
Infections caused by multidrug-resistant (MDR) bacteria, extended spectrum β-lactamase (ESBL), metallo-β-lactamase (MBL) and AmpC-β-lactamase (AmpC-βL)-producers are increasing globally. This study identified bacteria in clinical and tap water samples and determined the prevalence of MDR, and β-lactamase enzymes and genes.
METHODS
Isolates were identified by the Vitek 2 (bioMérieux, France) automated system. Antibiotic resistance and screening for β-lactamase enzymes and genes was done using disc diffusion method and Vitek 2 automated system, CHROMagar-ESBL, combined double disc, inhibition-based method and multiplex polymerase chain reaction, respectively.
RESULTS
The Enterobacteriaceae isolates obtained were , , spp., , , , , , , and . Of the 674 isolates from clinical samples, 36.5%, 28.5%, and 19.9% were ESBL, MBL, and AmpC-βL producers, respectively. A low prevalence of AmpC-βL and MBL producers were obtained, with no significant difference (p<0.05) between the prevalence of ESBL and non-ESBL producers. Isolates exhibited varied levels of resistance to gentamicin, amoxicillin-clavulanic acid, ciprofloxacin, and tetracycline. The results showed that 54.6% of ESBL producers, 57.9% of MBL producers, and 62.8% of AmpC-βL producers were MDR strains. Of the 141 representative isolates tested, 36.9%, 15.6%, and 20.6% had only , , and , respectively; 5.7% possessed both and ; 7.1% possessed both and and 4.3% had both and .
CONCLUSIONS
This study found a high prevalence of β-lactamase producers, indicating the need for further research on the molecular epidemiology of β-lactamase producers and their impacts in the region.
PubMed: 38023952
DOI: 10.18683/germs.2023.1366 -
Cureus Oct 2023The tribe comprises , , and species. TheseGram-negative rods are of concern in that they are involved in diverse human infections, particularly in hospital settings....
BACKGROUND
The tribe comprises , , and species. TheseGram-negative rods are of concern in that they are involved in diverse human infections, particularly in hospital settings. In the last two decades, there has been a sharp increase in infections by multidrug-resistant (MDR) . Therefore, the objectives of this study were to: (i) assess the prevalence of infections caused by tribe , (ii)determine the antimicrobial susceptibility profile of the test isolates, and (iii) identify the underlying risk factors for acquisition of infection by MDR strains.
METHODS
During the period from January 2019 to December 2020, we conducted a retrospective review of the electronic medical and laboratory records of adult patients who received care at our institution. In addition, we analyzed the risk factors associated with acquisition of infections by members of the tribe using univariate and multivariate regression models.
RESULTS
Overall 403 adult patients (average age 59.69 ± 20.33 years) were enrolled into this study (196 males; 48.6%, and 207 females; 51.4%). was the leading pathogen (70.7%; n=285), followed by (20.1%; n=81), and species (9.2%; n=37). Most of the isolates were recovered from urine (59.3%; n=239), followed by wound swabs (23.1%; n=93), with the least from blood samples (1.7%; n=7). Out of 403 isolates, 27.3% (n=110) were found to be extended-spectrum β-lactamase (ESBL)-producers, whereas 18.4% (n=74) were MDR. Patient's age, concomitant diabetes mellitus (DM), and long hospital stays were independently associated with infection by MDR strains.
CONCLUSION
Infections by MDR are leading causes for morbidity in our tertiary-care facility. Strict adherence to infection control precautions, as well as effective implementation of antimicrobial stewardship programs, are crucial to overcome these superbugs.
PubMed: 38021780
DOI: 10.7759/cureus.47494 -
Germs Dec 2022This study aimed to determine the prevalence of multidrug-resistant Gram-negative bacteria (GNB) from blood cultures in a tertiary-care hospital and the multiplex PCR...
INTRODUCTION
This study aimed to determine the prevalence of multidrug-resistant Gram-negative bacteria (GNB) from blood cultures in a tertiary-care hospital and the multiplex PCR assay's ability to detect resistance genes.
METHODS
A total of 388 GNB isolates obtained from hospitalized patients between November 2019 and November 2021 were included in the study. Antimicrobial susceptibility testing was done by VITEK 2 system and broth microdilution method. Beta-lactamase-encoding genes were detected by multiplex PCR assays, BioFire-Blood Culture Identification 2 (BCID2) panel (bioMérieux, France). Extended-spectrum beta-lactamases (ESBLs) were detected phenotypically with VITEK AST-GN71 card (bioMérieux, France). The isolates of GNB were classified into multidrug-resistant, extensively-drug-resistant, and pandrug-resistant categories, and their prevalence and distribution in different wards, including coronavirus diseases 2019 (COVID-19) intensive care units (ICU), were calculated.
RESULTS
Results revealed that all isolates of and were multidrug-resistant as well as 91.6% of , 80.6% of , and 76.1% of , respectively. In fermentative bacteria, (58.1%), (16.1%), (9.7%) and (6.5%) genes were detected. More than half of (58.3%) and (53.7%) produced ESBLs. Among non-fermenters, the gene was carried by 55% of and 19.5% of . In the COVID-19 ICU, was the most common isolate (86.1%).
CONCLUSIONS
This study revealed high proportions of multidrug-resistant blood isolates and various underlying resistance genes in Gram-negative strains. The BCID2 panel seems to be helpful for the detection of the most prevalent resistance genes of fermentative bacteria.
PubMed: 38021186
DOI: 10.18683/germs.2022.1349