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Infection and Drug Resistance 2019(), an emerging pathogen, is able to trigger a pronounced pro-inflammatory response that results in lung dysfunction in cystic fibrosis (CF) patients. All previous...
(), an emerging pathogen, is able to trigger a pronounced pro-inflammatory response that results in lung dysfunction in cystic fibrosis (CF) patients. All previous isolates have been obtained from the respiratory samples of CF patients, with no reported cases of bacteremia. For the first time, we report isolates recovered twice from the blood cultures of a patient with liver cancer who had undergone allogeneic liver transplantation. These isolates were successfully identified by combining mass spectrometry and molecular techniques based on 16S rRNA sequencing methods. At the onset of the bacteremia, the patient's peripheral T, B and NK cell counts were 181.68/μL, 59.57/μL and 70.66/μL, respectively. The serum procalcitonin level, C-reactive protein level and peripheral neutrophil granulocyte percentage were 0.56 ng/mL, 61.00 mg/L and 96.8%, respectively. We found these isolates to be susceptible to ciprofloxacin and piperacillin/tazobactam and to be intermediate to amikacin. Previous studies have found isolates to be resistant. All of the data combined showed that compromised immune function from allogeneic liver transplantation plus immunosuppressive therapy contributes to the occurrence of bacteremia. Furthermore, the isolates demonstrated characteristic resistance profiles.
PubMed: 31695454
DOI: 10.2147/IDR.S227643 -
Transplantation Dec 2021Uncontrolled donation after circulatory death (DCD) donors are an extraordinary resource to increase the number of lungs available for transplantation. However, the risk...
BACKGROUND
Uncontrolled donation after circulatory death (DCD) donors are an extraordinary resource to increase the number of lungs available for transplantation. However, the risk of the warm ischemia resulting from cardiac arrest to irreversibly damage the organs is considerable. Moreover, graft preservation issues and organizational problems often worsen the dangerous effects of warm ischemia. Ex vivo lung perfusion (EVLP) enables us to evaluate and recondition lungs whose functionality is doubtful, as well as to overcome the difficulties related to time and logistics.
METHODS
We report the case of uncontrolled DCD lungs successfully treated with an exceptionally prolonged EVLP. Because the donor's blood count and liver biopsy showed signs of possible leukemia, EVLP was protracted up to 17 h while waiting for immunohistochemical analyses to rule out this diagnosis; eventually, the results came back negative, and the lungs were judged suitable for transplantation.
RESULTS
The recipient was a 32-y-old male individual with cystic fibrosis, colonized by Pandoraea pnomenusa. Bilateral transplantation required central extracorporeal membrane oxygenation. The patient was extubated after 36 h and was discharged 21 d after the operation. Despite early recolonization by Pandoraea pnomenusa and airway complications requiring pneumatic dilatation, he is alive and has a satisfactory respiratory function 15 mo after transplantation.
CONCLUSIONS
Uncontrolled DCD represents a challenge due to both logistical issues and the complexity of graft evaluation before procurement. EVLP with cellular perfusate could be a valuable tool to overcome these limits. Nonetheless, caution should be exercised when interpreting the effects of this technique on airway healing.
Topics: Extracorporeal Circulation; Humans; Lung; Lung Transplantation; Male; Organ Preservation; Perfusion; Tissue Donors; Warm Ischemia
PubMed: 33496562
DOI: 10.1097/TP.0000000000003646 -
Journal of Environmental Management Jul 2023P-Chloro-Meta-Xylenol (PCMX) is a widely used disinfectant. In the current pandemic scenario, its consumption has increased largely, and as a result, wastewater is...
P-Chloro-Meta-Xylenol (PCMX) is a widely used disinfectant. In the current pandemic scenario, its consumption has increased largely, and as a result, wastewater is loaded heavily with PCMX as a contaminant. Remediation of this ecologically toxic phenolic compound is therefore a burning issue. This study proposes an eco-friendly biosorption-based remediation technique to remove PCMX. A novel isolated phenol-resistant gram-negative bacterium, Pandoraea sp. strain BT102, is first encapsulated in biopolymeric calcium alginate beads. These beads are packed in a long adsorption tube and the contaminated water was passed through this packed tube resembling a plug flow reactor. This unique plug-flow set-up is capable of reducing PCMX concentration from 100 mg L to 2.85 μg L within 4 h using only 30 g of adsorbent, resulting in 99.99% removal efficiency. Adsorption isotherms and kinetics are studied using batch experimental data. A PCMX loading capacity of the encapsulated calcium alginate beads is found to be 961.7 mg g, and the Freundlich isotherm results suggested the phenomenon of cooperative adsorption. A good agreement of the pseudo-second-order kinetic model along with the intra-particle diffusion model suggests a multilayer diffusion-controlled adsorption process. Biosorption of PCMX by the bacterium-modified beads was confirmed by Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX), and Fourier-Transform Infrared spectroscopy (FT-IR) analyses. The application of multivariate model-based Response Surface Methodology (RSM) reveals flow rate to be the most important factor controlling the rate of bioremediation.
Topics: Alginates; Spectroscopy, Fourier Transform Infrared; Phenols; Bacteria; Adsorption; Kinetics; Hydrogen-Ion Concentration; Water Pollutants, Chemical
PubMed: 36989918
DOI: 10.1016/j.jenvman.2023.117764 -
Journal of Global Antimicrobial... Mar 2024Gram-negative pathogens causing respiratory infection in people with cystic fibrosis and bronchiectasis are becoming progressively more resistant to conventional...
OBJECTIVES
Gram-negative pathogens causing respiratory infection in people with cystic fibrosis and bronchiectasis are becoming progressively more resistant to conventional antibiotics. Although cefiderocol is licenced for the treatment of infections due to Gram-negative organisms, there are limited data on the activity of cefiderocol against pathogens associated with chronic respiratory diseases. The aim of this study was to determine the susceptibility of Gram-negative pathogens from cystic fibrosis and bronchiectasis to cefiderocol and comparator antibiotics.
METHODS
Minimal inhibitory concentrations (MICs) of cefiderocol and 15 comparator antibiotics were determined by broth microdilution against 300 respiratory isolates: Burkholderia spp., Stenotrophomonas spp., Achromobacter spp., Ralstonia spp. and Pandoraea spp., and used to calculate the MIC of each antibiotic required to inhibit 50% (MIC) and 90% (MIC) of isolates.
RESULTS
The MIC and MIC of cefiderocol for all 300 isolates tested was 0.25 and 32 mg/L, with 232 (77.3%) isolates having an MIC value ≤2 mg/L. In addition, cefiderocol demonstrated excellent activity against Stenotrophomonas spp. and Achromobacter spp. isolates, with 86.7% and 87.2%, respectively, exhibiting an MIC of 2 mg/L. Tigecycline also demonstrated good activity against all isolates with an MIC of <0.5 mg/L.
CONCLUSIONS
These in vitro data demonstrated that cefiderocol had greater activity than most comparator antibiotics and could be an alternative treatment option for respiratory infection caused by these pathogens that has not responded to first-line therapy.
Topics: Humans; Cefiderocol; Cephalosporins; Cystic Fibrosis; Gram-Negative Bacteria; Drug Resistance, Multiple, Bacterial; Anti-Bacterial Agents; Bronchiectasis; Respiratory Tract Infections
PubMed: 38336228
DOI: 10.1016/j.jgar.2024.01.023 -
Antonie Van Leeuwenhoek Dec 2021A polyphasic taxonomic approach was used to characterize a Gram-stain-negative bacterium, designated strain CC-CFT501, harboring xenobiotic- and...
Zeimonas arvi gen. nov., sp. nov., of the family Burkholderiaceae, harboring biphenyl- and phenolic acid-metabolizing genes, isolated from a long-term ecological research field.
A polyphasic taxonomic approach was used to characterize a Gram-stain-negative bacterium, designated strain CC-CFT501, harboring xenobiotic- and allelochemical-metabolizing genes, isolated from a long-term ecological research field in Taiwan. Cells of strain CC-CFT501 were catalase- and oxidase-positive, non-motile and short rods. Optimal growth occurred at 30 °C, pH 8 and 1% NaCl. Strain CC-CFT501 was found to share high 16S rRNA gene sequence similarity with the members of genera Quisquiliibacterium (94.3%, n = 1), Pandoraea (93.4-94.0%, n = 23) and Paraburkholderia (93.3-94.0%, n = 9), affiliated to the family Burkholderiaceae. Strain CC-CFT501 shared 76.4% orthologous average nucleotide identity (OrthoANI) and 20.9% digital DNA-DNA hybridization (dDDH) values with Quisquiliibacterium transsilvanicum DSM 29781. Draft genome sequence (3.83 Mb) of strain CC-CFT501 revealed several genes encoding the proteins involved in biphenyl and phenolic acid metabolism. Fatty acid profile contained C, C, C 3-OH, C ω7c/C ω6c and C ω7c/C ω6c in predominant amounts. The polar lipid profile consisted of phosphatidylethanolamine, thirteen unidentified amino lipids, two unidentified phospholipids and two unidentified glycolipids. The major polyamine was spermidine and ubiquinone Q-8 was the sole respiratory quinone. The DNA G + C content was 70.0 mol%. Based on its distinct phylogenetic, phenotypic and chemotaxonomic traits together with results of comparative 16S rRNA gene sequence, ANI and dDDH analyses, strain CC-CFT501 is considered to represent a novel genus and species of the family Burkholderiaceae, for which the name Zeimonas arvi gen. nov., sp. nov. is proposed. The type strain of the type species is CC-CFT501 (= BCRC 81218 = JCM 33506).
Topics: Bacterial Typing Techniques; Biphenyl Compounds; Burkholderiaceae; DNA, Bacterial; Fatty Acids; Hydroxybenzoates; Phospholipids; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA
PubMed: 34599477
DOI: 10.1007/s10482-021-01664-x -
Antimicrobial Agents and Chemotherapy Mar 2020
Topics: Cystic Fibrosis; Glucose; Gram-Negative Bacteria; Humans; Microbial Sensitivity Tests; beta-Lactamase Inhibitors
PubMed: 32209566
DOI: 10.1128/AAC.00011-20 -
Microbiology Resource Announcements Jan 2020strain TF-18 was isolated from the roots of rice seedlings on selective medium containing four classes of antibiotics for isolation of Using Pacific Biosciences...
strain TF-18 was isolated from the roots of rice seedlings on selective medium containing four classes of antibiotics for isolation of Using Pacific Biosciences (PacBio) single-molecule real-time (SMRT) sequencing technology, we report here a complete genome of 5,499,432 bases, a GC content of 64.8%, and 4,849 coding sequences.
PubMed: 31896624
DOI: 10.1128/MRA.01008-19 -
The Journal of General and Applied... Jan 2020Siderophores are considered to have a good potential as decontamination agents owing to their metal-chelating abilities. In order to confirm whether siderophores can be...
Siderophores are considered to have a good potential as decontamination agents owing to their metal-chelating abilities. In order to confirm whether siderophores can be used in the recovery of metal ions, a siderophore (or metallophore) exhibiting Co-chelating activity was screened to demonstrate its ability to recover Co from an aqueous solution. A siderophore-producing bacterium, Pandoraea sp. HCo-4B, was identified from a screen of Co-resistant bacteria grown in an aerobic enrichment culture with a Co-supplemented medium. After incubation of the crude extracted siderophore in a Co-containing solution, the Co-siderophore complex was adsorbed on to a C column. The bound Co was eluted from the column by the addition of 10 mM HSO. The recovered amount of Co was proportional to the amount of the added siderophore. We observed that the siderophore identified in this study binds to Co at a 1:1 ratio.
Topics: Burkholderiaceae; Cobalt; Culture Media; Siderophores
PubMed: 31019144
DOI: 10.2323/jgam.2018.12.001