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Journal of Microbiology, Immunology,... Jun 2024For 29 parent strains, recognized by pulsed-field gel electrophoresis, the MICs multiplied significantly in the ciprofloxacin group than levofloxacin group, following...
For 29 parent strains, recognized by pulsed-field gel electrophoresis, the MICs multiplied significantly in the ciprofloxacin group than levofloxacin group, following the first and third induction cycle. Ser83Arg in GyrA was the most common site of mutations. No mutation in ParC nor ParE was identified in the selected mutants.
PubMed: 38871614
DOI: 10.1016/j.jmii.2024.05.011 -
Access Microbiology 2024To isolate specific bacteria from samples constituting the microbiota, it is essential to employ selective media that suppress the growth of resident bacteria other than...
To isolate specific bacteria from samples constituting the microbiota, it is essential to employ selective media that suppress the growth of resident bacteria other than specific target bacteria. Selective media for clinically important (including , which was previously taxonomically classified as part of the genus ) have been limited because they have been designed for a limited range of species within the genus and require ingredients which are difficult to prepare and handle. This study aimed to develop a selective medium [referred to as and Selective Medium (ASSM)] for the isolation of a broad range of and species from samples mixed with resident bacteria. The composition of ASSM includes yeast extract, agar, brain heart infusion (BHI), levofloxacin (LVFX), fosfomycin (FOM), colistin (CL) and metronidazole (MNZ). Evaluation of the medium using 24 swab samples serially collected from the roots of the teeth of a healthy individual for whom metagenome sequencing data of a saliva sample are publicly available revealed that ASSM adjusted to concentrations of LVFX 0.5 mg l, FOM 5 mg l, CL 1 mg l and MNZ 2 mg l and cultured anaerobically at 35 °C for 7 days enabled the isolation of species from 37.5 % of the samples. The inclusion of CL and MNZ in ASSM can also be useful for samples harbouring other bacterial species. The selective isolation medium is expected to contribute to studies investigating the relationship between these bacteria and their pathogenesis or disease.
PubMed: 38868375
DOI: 10.1099/acmi.0.000768.v3 -
Heliyon Jun 2024To detect levofloxacin (LFX) and moxifloxacin (MFX) resistance among rifampicin-resistant tuberculosis (RR-TB) isolates, and predict the resistance level based on...
OBJECTIVE
To detect levofloxacin (LFX) and moxifloxacin (MFX) resistance among rifampicin-resistant tuberculosis (RR-TB) isolates, and predict the resistance level based on specific mutations in and genes.
METHODS
A total of 686 RR-TB isolates were collected from Chinese Drug Resistance Surveillance Program from 2013 to 2020. The minimum inhibitory concentrations (MICs) of 12 anti-TB drugs were acquired using the broth microdilution method, followed by whole genome sequencing (WGS) analysis.
RESULTS
Among the 686 RR isolates, the most prevalent resistance was to isoniazid (80.5 %) and ethambutol (28.4 %), followed by LFX (26.1 %) and MFX (21.9 %). The resistance rate of LFX (26.1%-99.4 %) was higher than that of MFX (21.9%-83.3 %) across various drug resistance patterns. Of the 180 fluoroquinolones (FQs) resistant isolates, 168 (93.3 %) had mutations in quinolone-resistant determining regions (QRDRs) with 21 mutation types, and Asp94Gly (32.7 %, 55/168) was the predominant mutation. Isolates with mutations in Asp94Asn and Asp94Gly were associated with high levels of resistance to LFX and MFX. Using broth microdilution method as gold standard, the sensitivities of WGS for LFX and MFX were 93.3 % and 98.0 %, and the specificities were 98.6 % and 95.0 %, respectively.
CONCLUSION
The resistance rate of LFX was higher than that of MFX among various drug resistance patterns in RR-TB isolates. The Asp94Gly was the predominant mutation type underlying FQs resistance. However, no significant difference was observed between mutation patterns in gene and resistance level of FQs.
PubMed: 38868072
DOI: 10.1016/j.heliyon.2024.e31959 -
Heliyon Jun 2024Perforation of the tympanic membrane (TM) is a common condition that often requires a scaffold as a support for surgery. However, because of the external environment of...
Perforation of the tympanic membrane (TM) is a common condition that often requires a scaffold as a support for surgery. However, because of the external environment of the auditory canal, the scaffold could become bacterially infected and prevent the TM from healing. As a result, the perfect scaffold should have both antibacterial and biomimetic qualities. In this study, the biodegradable biomaterial poly(1,4-butylene carbonate) (PBC) films containing levofloxacin (LEV) was successfully prepared for the first time. The results showed that the hydrophilicity of the LEV/PBC film was improved after the addition of LEV, and the tensile strength was also complied with the requirements of the standard. The created antibacterial film demonstrated excellent antibacterial properties. In vitro hemolysis experiments revealed no risk of hemolysis for the new material, and the cytotoxicity study further confirmed its non-cytotoxic nature. Overall, LEV was a good component of PBC/LEV film, which is expected to be used for TM repair in the future.
PubMed: 38868060
DOI: 10.1016/j.heliyon.2024.e31789 -
Journal of Global Antimicrobial... Jun 2024Streptococcus agalactiae is a recognized pathogen that primarily affects infants and pregnant women. However, its increasingly important role in causing invasive...
BACKGROUND
Streptococcus agalactiae is a recognized pathogen that primarily affects infants and pregnant women. However, its increasingly important role in causing invasive infections among non-pregnant adults has become a significant health concern due to the severity and variety of its clinical impacts.
METHODS
Nonduplicate S. agalactiae clinical strains associated with clinical infections (n=139) were isolated from non-pregnant adults in Shandong, China. Antibiotic susceptibility testing, whole-genome sequencing, and genomic analyses were conducted to characterize the genome and identify resistance features of these strains.
RESULTS
The strains exhibited universal susceptibility to penicillin, ampicillin, cefotaxime, meropenem, linezolid, and vancomycin. Notably, high resistance rates were observed for erythromycin (91.4%), clindamycin (89.2%), levofloxacin (84.2%), tetracycline (54.0%) and, to a lesser extent, chloramphenicol (12.9%). Serotyping revealed seven serotypes and one non-typeable strain. Serotypes Ia, Ib, III, and V predominated, representing 95.7% of the strains. Nineteen sequence types were categorized into seven clonal complexes, with CC10 being the most prevalent at 48.9%. The resistance genes mreA (100%), ermB (70.5%), and tetM (46.0%) were commonly detected. All the isolates carried at least one pilus backbone determinant and one alpha-like protein gene, with the PI-1+PI-2a and the bca gene being the most frequent at 84.2% and 54.7%, respectively.
CONCLUSIONS
While S. agalactiae strains in non-pregnant adults retain sensitivity to β-lactam antibiotics, the elevated resistance to erythromycin, clindamycin, levofloxacin, and tetracycline is concerning. Given the growing elderly population worldwide, the burden of S. agalactiae infections is significant. Continuous surveillance of serotype distribution and antibiotic resistance patterns is imperative for targeted prevention and therapeutic strategies.
PubMed: 38866137
DOI: 10.1016/j.jgar.2024.06.001 -
Journal of Infection in Developing... May 2024Mycobacterium canariasense is a relatively rare and rapidly growing nontuberculous mycobacterium (NTM) infection.
INTRODUCTION
Mycobacterium canariasense is a relatively rare and rapidly growing nontuberculous mycobacterium (NTM) infection.
CASE REPORT
This case report describes a 36-year-old man with a Canariasense infection in the lung with solitary cavitation nodules located subpleural on CT scan, for which the final diagnosis was made by metagenomic next-generation sequencing (mNGS) of bronchoalveolar lavage fluid (BALF-mNGS). It was successfully treated with levofloxacin and amikacin.
CONCLUSIONS
This experience is instructive because clinical diagnostic and CT imaging characteristics and treatment strategy guidelines for pulmonary infections caused by M. canariasense have not yet been established.
Topics: Humans; Male; Adult; Mycobacterium Infections, Nontuberculous; Anti-Bacterial Agents; Tomography, X-Ray Computed; Bronchoalveolar Lavage Fluid; Lung; Levofloxacin; Amikacin; Nontuberculous Mycobacteria; High-Throughput Nucleotide Sequencing; Treatment Outcome
PubMed: 38865393
DOI: 10.3855/jidc.18535 -
Frontiers in Pediatrics 2024The impact of the coronavirus disease 2019 (COVID-19) pandemic on neonatal necrotizing enterocolitis (NEC) is not well characterised. This cross-sectional study...
BACKGROUND
The impact of the coronavirus disease 2019 (COVID-19) pandemic on neonatal necrotizing enterocolitis (NEC) is not well characterised. This cross-sectional study evaluated the potential effects of pandemic-related measures on NEC morbidity in premature infants in a neonatal ward during the COVID-19 pandemic.
METHODS
This was a retrospective study conducted in a tertiary neonatal ward in eastern and central China over 6 consecutive years (2017, 2018, 2019, 2020, 2021 and 2022). The medical records of 189 premature infants with stage II or III NEC were reviewed for clinical manifestations and aetiologies. The data were analysed and compared between the prepandemic period (2017, 2018, and 2019) and the pandemic period (2020, 2021 and 2022).
RESULTS
A total of 9,903 infants with gestational age (GA) < 37 weeks were enrolled, including 5,382 in the prepandemic period and 4,521 in the pandemic period. A reduction in stage II or III NEC morbidity was observed in infants with GA < 37 weeks, with an average annual morbidity of 2.29% (123/5,382) (95% CI, 1.89%-2.68%) in the prepandemic period and 1.46% (66/4,521) (95% CI, 1.11%-1.81%) in the pandemic period. NEC morbidity showed resurgent characteristics in 2021. When prepandemic coinfections were excluded, most cases of NEC with bloodstream infections in the prepandemic period were attributable to Gram-negative bacteria (27/32, 84.38%), mainly , while in the pandemic period they were attributable to Gram-positive bacteria (10/18, 55.56%), mainly . Antimicrobial susceptibility testing revealed that was 100% sensitive to meropenem, imipenem, ciprofloxacin and levofloxacin and 100% resistant to ampicillin. was 100% sensitive to vancomycin, linezolid, tetracycline, cotrimoxazole and cefoxitin and 100% resistant to penicillin and benzathine.
CONCLUSIONS
COVID-19 pandemic-related interventions can reduce the morbidity of NEC and change the pathogen spectrum in patients with bloodstream infections. We need to understand the exact factors leading to these changes.
PubMed: 38863524
DOI: 10.3389/fped.2024.1346478 -
PloS One 2024Whole Genome Sequencing (WGS) is a promising tool in the global fight against tuberculosis (TB). The aim of this study was to evaluate the use of WGS in routine...
Whole Genome Sequencing (WGS) is a promising tool in the global fight against tuberculosis (TB). The aim of this study was to evaluate the use of WGS in routine conditions for detection of drug resistance markers and transmission clusters in a multidrug-resistant TB hot-spot area in Peru. For this, 140 drug-resistant Mycobacterium tuberculosis strains from Lima and Callao were prospectively selected and processed through routine (GenoType MTBDRsl and BACTEC MGIT) and WGS workflows, simultaneously. Resistance was determined in accordance with the World Health Organization mutation catalogue. Agreements between WGS and BACTEC results were calculated for rifampicin, isoniazid, pyrazinamide, moxifloxacin, levofloxacin, amikacin and capreomycin. Transmission clusters were determined using different cut-off values of Single Nucleotide Polymorphism differences. 100% (140/140) of strains had valid WGS results for 13 anti-TB drugs. However, the availability of final, definitive phenotypic BACTEC MGIT results varied by drug with 10-17% of invalid results for the seven compared drugs. The median time to obtain results of WGS for the complete set of drugs was 11.5 days, compared to 28.6-52.6 days for the routine workflow. Overall categorical agreement by WGS and BACTEC MGIT for the compared drugs was 96.5%. Kappa index was good (0.65≤k≤1.00), except for moxifloxacin, but the sensitivity and specificity values were high for all cases. 97.9% (137/140) of strains were characterized with only one sublineage (134 belonging to "lineage 4" and 3 to "lineage 2"), and 2.1% (3/140) were mixed strains presenting two different sublineages. Clustering rates of 3.6% (5/140), 17.9% (25/140) and 22.1% (31/140) were obtained for 5, 10 and 12 SNP cut-off values, respectively. In conclusion, routine WGS has a high diagnostic accuracy to detect resistance against key current anti-TB drugs, allowing results to be obtained through a single analysis and helping to cut quickly the chain of transmission of drug-resistant TB in Peru.
Topics: Mycobacterium tuberculosis; Peru; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing; Humans; Antitubercular Agents; Polymorphism, Single Nucleotide; Drug Resistance, Multiple, Bacterial; Microbial Sensitivity Tests; Genome, Bacterial; Male; Female
PubMed: 38861531
DOI: 10.1371/journal.pone.0304130 -
Clinical Case Reports Jun 2024The most frequently reported adverse reaction to zoledronic acid is an acute phase reaction resembling influenza. While rarer adverse events such as osteonecrosis of the...
The most frequently reported adverse reaction to zoledronic acid is an acute phase reaction resembling influenza. While rarer adverse events such as osteonecrosis of the jaw and atypical femoral fractures have gained significant recognition, the ocular adverse effects, particularly scleritis, are not yet fully comprehended. Here, we present the case of a 75-year-old female patient with osteoporosis who developed bilateral redness and intense eye pain 48 h after receiving a 5 mg intravenous dose of zoledronic acid. Clinical presentation suggested bilateral conjunctivitis, but treatment with levofloxacin eye drops and acyclovir ophthalmic gel exacerbated the symptoms over 2 days, predominantly affecting the left eye. Ocular ultrasonography revealed thickening of the left eyeball wall with a "T" sign, while an orbital CT scan showed increased thickness of the left sclera. Treatment with methylprednisolone 80 mg intravenous infusion twice daily led to gradual symptom improvement and eventual resolution of inflammation. This report, based on a review of relevant literature, investigates the treatment and outcomes of zoledronic acid-induced scleritis, emphasizing the importance for clinicians to promptly identify and manage this rare and serious ocular adverse reaction.
PubMed: 38855089
DOI: 10.1002/ccr3.9068 -
Iranian Journal of Microbiology Apr 2024is an opportunistic pathogen causing nosocomial infections. Diclofenac is an anti-inflammatory drug that is considered a non-antibiotic drug. This study assessed the...
BACKGROUND AND OBJECTIVES
is an opportunistic pathogen causing nosocomial infections. Diclofenac is an anti-inflammatory drug that is considered a non-antibiotic drug. This study assessed the antibacterial and antibiofilm effects of diclofenac and levofloxacin/diclofenac combination against levofloxacin resistant isolates.
MATERIALS AND METHODS
Minimum inhibitory concentration was determined using broth microdilution method for levofloxacin, diclofenac, and levofloxacin/diclofenac combination. Biofilm forming capacity and biofilm inhibition assay were determined. Relative gene expression was measured for efflux pump genes; , and genes and biofilm related genes , and without and with diclofenac and the combination.
RESULTS
Diclofenac demonstrated MIC of 1 mg/ml. The combination-with ½ MIC diclofenac-showed synergism where levofloxacin MIC undergone 16-32 fold decrease. All the isolates that overexpressed and showed a significant decrease in gene expression in presence of diclofenac or the combination. The mean percentage inhibition of biofilm formation with diclofenac and the combination was 40.59% and 46.49%, respectively. This agreed with biofilm related genes expression investigations.
CONCLUSION
Diclofenac showed an antibacterial effect against The combination showed synergism, significant reduction in biofilm formation and in the relative level of gene expression. Furthermore, it can potentiate the levofloxacin activity or revert its resistance.
PubMed: 38854979
DOI: 10.18502/ijm.v16i2.15349