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Journal of Laboratory Physicians Sep 2023species has become a leading cause of nosocomial infections in recent years. The aim of the study was to establish the usefulness of matrix-assisted laser...
species has become a leading cause of nosocomial infections in recent years. The aim of the study was to establish the usefulness of matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF) mass spectrometry (MS) for the identification of species with respect to conventional biochemical methods and MicroScan WalkAway 96 Plus system and to compare the antibiotic susceptibility test results Kirby-Bauer disk diffusion method with MicroScan WalkAway 96 Plus automated identification and antimicrobial susceptibility testing system. The study sample comprised 100 clinical isolates of species. They were all identified using MALDI-TOF MS and compared with other two identification systems. Comparison of categorical variables by Fisher's exact test or Pearson's chi-square test was done. All statistical tools were two tailed, and a significant level < 0.05 was used. All statistical tests were performed using SPSS v22.0 (Armonk IBM Corp., New York, United States). Cohen's kappa coefficients were also calculated and used as applicable. MALDI-TOF MS revealed 92 , 2 , 3 , and 1 each was identified as , , and . There was moderate agreement between identification by MicroScan WalkAway and MALDI-TOF, and substantial agreement between conventional biochemical tests and MALDI-TOF. We found that there was a 100% categorical agreement with respect to susceptibility of aminoglycosides (amikacin, gentamicin, tobramycin) and cephalosporins (ceftazidime, cefepime, cefotaxime) between disk diffusion method and MicroScan WalkAway 96 Plus system. Total of 16 errors were observed. Although MALDI-TOF MS could be useful to identify but not other species in the genus, it is a rapid, reliable method and can be routinely used in clinical laboratories.
PubMed: 37564221
DOI: 10.1055/s-0042-1760401 -
Communications Biology Oct 2022Incomplete documentary evidence, variable biomolecular preservation, and limited skeletal responses have hindered assessment of acute infections in the past. This study...
Incomplete documentary evidence, variable biomolecular preservation, and limited skeletal responses have hindered assessment of acute infections in the past. This study was initially developed to explore the diagnostic potential of dental calculus to identify infectious diseases, however, the breadth and depth of information gained from a particular individual, St. Louis Individual (St.LI), enabled an individualized assessment and demanded broader disciplinary introspection of ethical research conduct. Here, we document the embodiment of structural violence in a 23-year-old Black and/or African American male, who died of lobar pneumonia in 1930s St. Louis, Missouri. St.LI exhibits evidence of systemic poor health, including chronic oral infections and a probable tuberculosis infection. Metagenomic sequencing of dental calculus recovered three pre-antibiotic era pathogen genomes, which likely contributed to the lobar pneumonia cause of death (CoD): Klebsiella pneumoniae (13.8X); Acinetobacter nosocomialis (28.4X); and Acinetobacter junii (30.1X). Ante- and perimortem evidence of St.LI's lived experiences chronicle the poverty, systemic racism, and race-based structural violence experienced by marginalized communities in St. Louis, which contributed to St.LI's poor health, CoD, anatomization, and inclusion in the Robert J. Terry Anatomical Collection. These same embodied inequalities continue to manifest as health disparities affecting many contemporary communities in the United States.
Topics: Adult; Black or African American; Anti-Bacterial Agents; Bacterial Infections; Dental Calculus; Humans; Male; United States; Violence; Young Adult
PubMed: 36192528
DOI: 10.1038/s42003-022-03890-z -
MSphere Jan 2021nasal carriage provides the bacterial reservoir for opportunistic infection. In comparing the nasal microbiomes of culture-defined persistent carriers versus...
nasal carriage provides the bacterial reservoir for opportunistic infection. In comparing the nasal microbiomes of culture-defined persistent carriers versus noncarriers, we detected DNA in all noses, including those with an established history of negativity based on culture. Colonization with , including , , , and select spp., was associated with noncarriage. We next developed physiological competition assays for testing anti- activity of isolated nasal species, utilizing medium modeling the nutrient-limited fluid of the nasal mucosa, polarized primary nasal epithelia, and nasal secretions. from the nose of an noncarrier demonstrated >99% inhibition of recovery in all assays, even when was coincubated in 9-fold excess. Secreted inhibitory proteins from and were heat-stable and <30 kDa, fitting the profile of antimicrobial peptides. , , , and inhibited recovery on nasal epithelia in a contact-dependent manner, while several other species either had no effect or promoted growth. Collectively, this project is one of the first to identify resident nasal microbial species that impede survival, and it implies that detectable nasal results from shifts in microbial community composition. Nasal carriage of is a risk factor for infection, but it is not yet understood why some individuals carry nasal persistently, intermittently, or seemingly not at all when tested via culture methods. This study compared the nasal microbiomes of established carriers and noncarriers, identified species associated with noncarriage, and tested them for anti- activity using assays developed to model the nutrient-limited nasal mucosa. We determined that all nostril swabs contain DNA, even swabs from hosts considered to be long-term noncarriers. Select members of the class were more prevalent in noncarrier than carrier nostrils and demonstrated potent activity against multiple strains of The results described here provide a better understanding of how the nasal microbiome controls growth and viability and may be useful in the design of improved decolonization strategies.
Topics: Anti-Bacterial Agents; Antibiosis; Carrier State; Cells, Cultured; Epithelial Cells; Gammaproteobacteria; Humans; Microbiota; Nasal Cavity; Staphylococcus aureus
PubMed: 33408227
DOI: 10.1128/mSphere.01015-20 -
Cureus Nov 2021genus includes multiple species, most notably that constitutes a common cause of nosocomial infections worldwide, particularly in patients with underlying...
genus includes multiple species, most notably that constitutes a common cause of nosocomial infections worldwide, particularly in patients with underlying immunodeficiency and risk factors (e.g., prior broad-spectrum antibiotic therapy, central venous catheter, mechanical ventilation). is a very rare human pathogen that is particularly associated with outbreaks of sepsis in immunocompromised neonates and pediatric oncology patients and rarely in immunocompromised adults. To our knowledge, this is the first case report of cavitary pneumonia with bacteremia secondary to in a patient with systemic lupus erythematosus (SLE).
PubMed: 34976481
DOI: 10.7759/cureus.19711 -
Infection Dec 2014Rods of the Acinetobacter genus are present mainly in the external environment (e.g. water, soil) and in animals, while in humans they may comprise physiological flora....
Rods of the Acinetobacter genus are present mainly in the external environment (e.g. water, soil) and in animals, while in humans they may comprise physiological flora. The main pathogenic species is Acinetobacter baumannii complex, which constitutes a common cause of nosocomial infections, particularly in patients with underlying diseases and risk factors (e.g. prior broad-spectrum antibiotic therapy, malignancy, central venous catheter, mechanical ventilation); however, infections of the eye caused by strains of Acinetobacter spp. are very rare. We report a unique case of community-acquired corneal ulcer caused by Acinetobacter non-baumannii (possibly A. junii), in a patient with no risk factors identified. The case highlights the need for obtaining a sample from the cornea for bacteriological culture in the case of suspected ophthalmic infection as identification of the pathogen, and assessment of its susceptibility profile enables proper antibiotic therapy, improves the outcome and may constitute an eyesight-saving management.
Topics: Acinetobacter; Acinetobacter Infections; Anti-Bacterial Agents; Corneal Ulcer; Female; Humans; Middle Aged
PubMed: 25056128
DOI: 10.1007/s15010-014-0647-8 -
MicrobiologyOpen Mar 2021The intestinal symbiotic bacteria of Aedes albopictus play a potential role in host resistance to insecticides. In this study, we sequenced the full-length of 16S rRNA... (Comparative Study)
Comparative Study
The intestinal symbiotic bacteria of Aedes albopictus play a potential role in host resistance to insecticides. In this study, we sequenced the full-length of 16S rRNA and analyzed the differences in the intestinal microbiota between deltamethrin-resistant and -sensitive Ae. albopictus. Symbiotic bacteria were cultured and analyzed using six types of culture media in aerobic and anaerobic environments. We found significant differences in the diversity and abundance of the intestinal microbiota of the two strains of Ae. albopictus. The symbiotic bacteria cultured in vitro were found to be mainly facultative anaerobes. The cultured bacteria such as Serratia oryzae and Acinetobacter junii may function to promote the development of insecticide resistance. This work indicates that intestinal bacteria may contribute to the enhancement of insecticide resistance of Ae. albopictus It also highlights the analytical advantage of full-length 16S rRNA sequencing to study the intestinal microbiota of mosquitoes.
Topics: Aedes; Animals; Bacteria; Biodiversity; DNA, Bacterial; Gastrointestinal Microbiome; Insecticide Resistance; Insecticides; Larva; Nitriles; Pyrethrins; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Symbiosis
PubMed: 33970535
DOI: 10.1002/mbo3.1177 -
Scientific Reports Jan 2021In this study, sediments were collected from two different sites in the deep-sea hydrothermal region of the South Atlantic Ocean. Two microbial enrichment cultures (H7S...
In this study, sediments were collected from two different sites in the deep-sea hydrothermal region of the South Atlantic Ocean. Two microbial enrichment cultures (H7S and H11S), which were enriched from the sediments collected at two sample sites, could effectively degrade petroleum hydrocarbons. The bacterial diversity was analyzed by high-throughput sequencing method. The petroleum degradation ability were evaluated by gas chromatography-mass spectrometry and gravimetric analysis. We found that the dominant oil-degrading bacteria of enrichment cultures from the deep-sea hydrothermal area belonged to the genera Pseudomonas, Nitratireductor, Acinetobacter, and Brevundimonas. After a 14-day degradation experiment, the enrichment culture H11S, which was obtained near a hydrothermal vent, exhibited a higher degradation efficiency for alkanes (95%) and polycyclic aromatic hydrocarbons (88%) than the enrichment culture H7S. Interestingly, pristane and phytane as biomarkers were degraded up to 90% and 91% respectively by the enrichment culture H11S, and six culturable oil-degrading bacterial strains were isolated. Acinetobacter junii strain H11S-25, Nitratireductor sp. strain H11S-31 and Pseudomonas sp. strain H11S-28 were used at a density ratio of 95:4:1 to construct high-efficiency oil-degrading consortium H. After a three-day biodegradation experiment, consortium H showed high degradation efficiencies of 74.2% and 65.7% for total alkanes and PAHs, respectively. The degradation efficiency of biomarkers such as pristane and high-molecular-weight polycyclic aromatic hydrocarbons (such as CHR) reached 84.5% and 80.48%, respectively. The findings of this study indicate that the microorganisms in the deep-sea hydrothermal area are potential resources for degrading petroleum hydrocarbons. Consortium H, which was artificially constructed, showed a highly efficient oil-degrading capacity and has significant application prospects in oil pollution bioremediation.
PubMed: 33446871
DOI: 10.1038/s41598-021-80991-5 -
Journal of Applied Microbiology Jun 2015Despite electrophoretic patterns of ITS PCR amplicons often suggesting only a single ITS sequence variant is present in strains of Acinetobacter junii, sequence data...
AIMS
Despite electrophoretic patterns of ITS PCR amplicons often suggesting only a single ITS sequence variant is present in strains of Acinetobacter junii, sequence data shows differences in ITS copies between and among them. This paper set out to explain why these ITS variants arise, and whether their presence compromises the reliability of the ITS targeted methods currently available for typing Ac. junii strains.
METHODS AND RESULTS
ITS sequences from a number of strains of Ac. junii were either downloaded from public databases or generated here by cloning and sequencing ITS PCR amplicons. ITS copies of Ac. junii strain 97338 were all 666 bp long, with identical sequences. In Ac. junii ATCC 17908(T) /BCRC 14854(T) ), ITS copies were also all identical in their lengths but now were 706/7 bp long. Two sequence variants of these 707 bp ITS were detected. One was identical in its sequence to the nine ITS copies downloaded from the whole genome sequence of Ac. junii CIP 64·5, and those in several other Ac. junii strains. The other 707 bp ITS variant occurred elsewhere only in Ac. junii strain DSM 14968 of those examined. The six ITS copies from the genome sequence of Ac. junii NIPH 182 were all 685 bp, and with identical sequences. Ac. junii strain 178 also possessed this same 685 bp ITS variant, one of six variants detected there. At least five ITS sequence variants were seen in Ac. junii strain 97380, four in strain DSM 14968 and two in the whole genome of strain 107470.
CONCLUSIONS
As with those of other Acinetobacter species, such ITS variants arise not from intragenomic recombination events but from the presence of different length indels. These arise from horizontal gene transfers involving ITS fragments of other Acinetobacter species.
SIGNIFICANCE AND IMPACT OF THE STUDY
The presence of these indels compromises the reliability of the ITS targeted methods available for typing Acinetobacter junii. It also precludes the value of using ITS sequences as phylogenetic markers in members of the genus Acinetobacter, since the outcomes in both cases depends on which copy variant is chosen.
Topics: Acinetobacter; Base Sequence; DNA, Intergenic; Gene Transfer, Horizontal; Genetic Variation; Molecular Sequence Data; Phylogeny; Polymerase Chain Reaction; Reproducibility of Results
PubMed: 25801684
DOI: 10.1111/jam.12800 -
International Health Sep 2020The present study was carried out to investigate the tap water quality of public toilets in Amritsar, Punjab, India.
BACKGROUND
The present study was carried out to investigate the tap water quality of public toilets in Amritsar, Punjab, India.
METHODS
Water samples from the taps of the public toilets were collected in sterile containers and physicochemical and bacteriological analysis was performed using standard methods. Also, genotypic and phenotypic characterization of the bacterial isolates was performed using different biochemical tests and 16S ribosomal RNA analysis. An antibiotic susceptibility test was performed using antibiotics based on their mode of action. A biofilm assay was performed to assess the adhesion potential of the isolates.
RESULTS
A total of 25 bacterial isolates were identified from the water samples, including Acinetobacter junii, Acinetobacter pittii, Acinetobacter haemolyticus, Bacillus pumilus, Bacillus megaterium, Bacillus marisflavi, Bacillus flexus, Bacillus oceanisediminis, Pseudomonas otitidis, Pseudomonas sp. RR013, Pseudomonas sp. RR021, Pseudomonas sp. RR022, Escherichia coli and Enterobacter cloacae. The results of the antimicrobial susceptibility test revealed that the antibiotics cefodroxil, aztreonam, nitrofurantoin, cefepime, ceftazidime and amoxyclav were found to be mostly ineffective against various isolates. The biofilm assay revealed the weak, moderate and strong biofilm producers among them.
CONCLUSIONS
The tap water in the public toilets was microbially contaminated and needs to be monitored carefully. The antibiotic susceptibility profile showed that of 25 bacterial isolates, 5 were multidrug resistant. Bacterial isolates exhibited strong to weak adhesion potential in the biofilm assay.
Topics: Acinetobacter; Anti-Bacterial Agents; Bacillus; Bacterial Infections; Bathroom Equipment; Biofilms; Genotype; Humans; India; Microbial Sensitivity Tests; Phenotype; Pseudomonas; Water; Water Microbiology
PubMed: 31693132
DOI: 10.1093/inthealth/ihz074 -
Applied and Environmental Microbiology May 2020Resistance to the "last-resort" antibiotics, such as carbapenems, has led to very few antibiotics being left to treat infections by multidrug-resistant bacteria. Spread...
Resistance to the "last-resort" antibiotics, such as carbapenems, has led to very few antibiotics being left to treat infections by multidrug-resistant bacteria. Spread of carbapenem resistance (CR) has been well characterized for the clinical environment. However, there is a lack of information about its environmental distribution. Our study reveals that CR is present in a wide range of Gram-negative bacteria in the coastal seawater environment, including four phyla, eight classes, and 30 genera. These bacteria were likely introduced into seawater via stormwater flows. Some CR isolates found here, such as , , , , , , and , are further relevant to human health. We also describe a novel metallo-β-lactamase (MBL) for marine isolates with CR, which has likely been horizontally transferred to or In contrast, another MBL of the New Delhi type was likely acquired by environmental isolates from , , or utilizing a plasmid. Our findings add to the growing body of evidence that the aquatic environment is both a reservoir and a vector for novel CR genes. Resistance against the "last-resort" antibiotics of the carbapenem family is often based on the production of carbapenemases, and this has been frequently observed in clinical samples. However, the dissemination of carbapenem resistance (CR) in the environment has been less well explored. Our study shows that CR is commonly found in a range of bacterial taxa in the coastal aquatic environment and can involve the exchange of novel metallo-β-lactamases from typical environmental bacteria to potential human pathogens or vice versa. The outcomes of this study contribute to a better understanding of how aquatic and marine bacteria can act as reservoirs and vectors for CR outside the clinical setting.
Topics: Anti-Bacterial Agents; Aquatic Organisms; Carbapenems; Drug Resistance, Multiple, Bacterial; Fresh Water; Gram-Negative Bacteria; New South Wales
PubMed: 32198174
DOI: 10.1128/AEM.02939-19