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Dermatology Online Journal Apr 2024
Topics: Humans; Helicobacter Infections; Leukemia-Lymphoma, Adult T-Cell; Helicobacter pylori; Anti-Bacterial Agents; Male; Disease Progression; Middle Aged; Female
PubMed: 38959935
DOI: 10.5070/D330263595 -
Journal of Hazardous Materials Jul 2024Arsenic (As) is a groundwater contaminant of global concern. The degradation of dissolved organic matter (DOM) can provide a reducing environment for As release....
Arsenic (As) is a groundwater contaminant of global concern. The degradation of dissolved organic matter (DOM) can provide a reducing environment for As release. However, the interaction of DOM with local microbial communities and how different sources and types of DOM influence the biotransformation of As in aquifers is uncertain. This study used optical spectroscopy, Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), metagenomics, and structural equation modeling (SEM) to demonstrate the how the biotransformation of As in aquifers is promoted. The results indicated that the DOM in high-As groundwater is dominated by highly unsaturated low-oxygen(O) compounds that are quite humic and stable. Metagenomics analysis indicated Acinetobacter, Pseudoxanthomonas, and Pseudomonas predominate in high-As environments; these genera all contain As detoxification genes and are members of the same phylum (Proteobacteria). SEM analyses indicated the presence of Proteobacteria is positively related to highly unsaturated low-O compounds in the groundwater and conditions that promote arsenite release. The results illustrate how the biogeochemical transformation of As in groundwater systems is affected by DOM from different sources and with different characteristics.
PubMed: 38959833
DOI: 10.1016/j.jhazmat.2024.135047 -
Ecotoxicology and Environmental Safety Jul 2024University students predominantly spend their time indoors, where prolonged exposure raises the risk of contact with microorganisms of concern. However, our knowledge...
University students predominantly spend their time indoors, where prolonged exposure raises the risk of contact with microorganisms of concern. However, our knowledge about the microbial community characteristics on university campus and their underpinnings is limited. To address it, we characterized bacterial communities from the surfaces of various built environments typical of a university campus, including cafeterias, classrooms, dormitories, offices, meeting rooms, and restrooms, in addition to human skin. The classrooms harbored the highest α-diversity, while the cafeterias had the lowest α-diversity. The bacterial community composition varied significantly across different building types. Proteobacteria, Actinobacteria, Firmicutes, Bacteroidetes, and Cyanobacteria were common phyla in university buildings, accounting for more than 90 % of total abundance. Staphylococcus aureus was the most abundant potential pathogen in classrooms, dormitories, offices, restrooms, and on human skin, indicating a potential risk for skin disease infections in these buildings. We further developed a new quantitative pathogenic risk assessment method according to the threat of pathogens to humans and found that classrooms exhibited the highest potential risk. The fast expectation-maximization algorithm identified 59 %-86 % of bacterial sources in buildings, with the human skin as the largest bacterial source for most buildings. As the sources of bacteria were highly traceable, we showed that homogeneous selection, dispersal limitation, and ecological drift were major ecological forces that drove community assembly. Our findings have important implications for predicting the distribution and sources of indoor dust bacterial communities on university campus.
PubMed: 38959791
DOI: 10.1016/j.ecoenv.2024.116632 -
Australian Journal of General Practice Jul 2024There were 82.4 million new gonorrhoea cases worldwide in 2020. Dual treatment with ceftriaxone or cefixime and azithromycin or doxycycline is currently recommended for...
BACKGROUND AND OBJECTIVES
There were 82.4 million new gonorrhoea cases worldwide in 2020. Dual treatment with ceftriaxone or cefixime and azithromycin or doxycycline is currently recommended for gonorrhoea in Indonesia. However, reduced susceptibility and resistance to cephalosporins and azithromycin are increasing. We evaluated the susceptibility pattern of Neisseria gonorrhoeae to cefixime, ceftriaxone, azithromycin and doxycycline.
METHOD
N. gonorrhoeae isolates were obtained from 19 male participants with clinically and laboratory-confirmed gonorrhoea. Antibiotic susceptibility testing was conducted by disc diffusion and interpreted according to Clinical and Laboratory Standards Institute and Centers for Disease Control and Prevention criteria.
RESULTS
Reduced susceptibility or resistance was observed against doxycycline in 19 isolates (100%), cefixime in six (31.6%), ceftriaxone in three (15.8%) and azithromycin in zero (0%) isolates.
DISCUSSION
A dual treatment regimen with ceftriaxone and azithromycin can still be recommended as first-line therapy for gonorrhoea in Indonesia. Antibiotic susceptibility surveillance of N. gonorrhoeae should be routinely conducted.
Topics: Humans; Indonesia; Neisseria gonorrhoeae; Anti-Bacterial Agents; Gonorrhea; Male; Microbial Sensitivity Tests; Azithromycin; Doxycycline; Ceftriaxone; Adult; Cefixime; Primary Health Care; Drug Resistance, Bacterial; Drug Therapy, Combination
PubMed: 38959520
DOI: 10.31128/AJGP-05-23-6845 -
Science Advances Jul 2024Ice-nucleating proteins (INpro) trigger the freezing of supercooled water droplets relevant to atmospheric, biological, and technological applications. The high ice...
Ice-nucleating proteins (INpro) trigger the freezing of supercooled water droplets relevant to atmospheric, biological, and technological applications. The high ice nucleation activity of INpro isolated from the bacteria could be linked to the aggregation of proteins at the bacterial membrane or at the air-water interface (AWI) of droplets. Here, we imaged freezing onsets, providing direct evidence of these proposed mechanisms. High-speed cryo-microscopy identified the onset location of freezing in droplets between two protein-repellent glass slides. INpro from sterilized (Snomax) statistically favored nucleation at the AWI of the droplets. Removing cellular fragments by filtration or adding surfactants increased the frequency of nucleation events at the AWI. On the other hand, cultivated intact bacteria cells or lipid-free droplets nucleated ice without an affinity to the AWI. Overall, we provide visual evidence that INpro from trigger freezing at hydrophobic interfaces, such as the AWI or the bacterial membrane, with important mechanistic implications for applications of INpro.
Topics: Pseudomonas syringae; Freezing; Hydrophobic and Hydrophilic Interactions; Bacterial Outer Membrane Proteins; Ice; Bacterial Proteins
PubMed: 38959312
DOI: 10.1126/sciadv.adn6606 -
PloS One 2024Evidence supports that people identifying as a sexual or gender minority (SGMs) experience minority-related stress resulting from discrimination or expectations of...
Evidence supports that people identifying as a sexual or gender minority (SGMs) experience minority-related stress resulting from discrimination or expectations of prejudice, and that this is associated with increased mental and physical health problems compared to cisgender heterosexuals. However, the biological mechanisms driving minority-related stress impacts remain unknown, including the role of the gut microbiome. Thus, the aim of this study was to determine the relationship between SGM status and gut microbiome health among young adults attending a 4-year university. To this end, a prospective pilot study was completed in the fall and spring semesters of 2021-22. Self-identified SGMs (N = 22) and cisgender-heterosexuals (CIS-HET, N = 43) completed in-person interviews to provide mental health data and demographic information. Nail and saliva samples were collected at the time of interview to quantify chronic and acute cortisol. Stool samples were collected within 48 hours of interview for microbiome analysis. Assessment of the gut microbiota identified a significant reduction in alpha diversity among the SGM group, even when adjusting for mental health outcome. SGM group showed trends for higher abundance of microbes in phylum Bacteroidetes and lower abundance of microbes in phyla Firmicutes, Actinobacteria, and Proteobacteria compared to the CIS-HET group. These findings support that the gut microbiome could be contributing to negative health effects among the SGM community.
Topics: Humans; Male; Female; Pilot Projects; Sexual and Gender Minorities; Gastrointestinal Microbiome; Young Adult; Adult; Prospective Studies; Feces; Hydrocortisone; Saliva; Adolescent; Stress, Psychological
PubMed: 38959280
DOI: 10.1371/journal.pone.0306638 -
PloS One 2024Mixture toxicity was determined for 32 binary combinations. One chemical was the non-reactive, non-polar narcotic 3-methyl-2-butanone (always chemical A) and the other...
Mixture toxicity was determined for 32 binary combinations. One chemical was the non-reactive, non-polar narcotic 3-methyl-2-butanone (always chemical A) and the other was a potentially reactive electrophile (chemical B). Bioluminescence inhibition in Allovibrio fischeri was measured at 15-, 30-, and 45-minutes of exposure for A, B, and the mixture (MX). Concentration-response curves (CRCs) were developed for each chemical and used to develop predicted CRCs for the concentration addition (CA) and independent action (IA) mixture toxicity models. Also, MX CRCs were generated and compared with model predictions using the 45-minute data. Classification of observed mixture toxicity used three specific criteria: 1) predicted IA EC50 vs. CA EC50 values at 45-minutes, 2) consistency of 45-minute MX CRC fit to IA, CA, or otherwise at three effect levels (EC25, EC50 and EC75), and 3) the known/suspected mechanism of toxicity for chemical B. Mixture toxicity was then classified into one of seven groupings. As a result of the predicted IA EC50 being more toxic than the predicted CA EC50, IA represented the greater toxic hazard. For this reason, non-sham MXs having toxicity consistent with CA were classified as being "coincident" with CA rather than mechanistically-consistent with CA. Multiple linear regression analyses were performed to develop equations that can be used to estimate the toxicity of other 3M2B-containing binary mixtures. These equations were developed from the data for both IA and CA, at each exposure duration and effect level. Each equation had a coefficient of determination (r2) above 0.950 and a variance inflation factor <1.2. This approach can potentially reduce the need for mixture testing and is amenable to other model systems and to assays that evaluate toxicity at low effect levels.
Topics: Aliivibrio fischeri; Butanones; Dose-Response Relationship, Drug; Toxicity Tests
PubMed: 38959231
DOI: 10.1371/journal.pone.0306382 -
PloS One 2024Salmonella infections pose a significant global public health concern due to the substantial expenses associated with monitoring, preventing, and treating the infection....
Salmonella infections pose a significant global public health concern due to the substantial expenses associated with monitoring, preventing, and treating the infection. In this study, we explored the core proteome of Salmonella to design a multi-epitope vaccine through Subtractive Proteomics and immunoinformatics approaches. A total of 2395 core proteins were curated from 30 different isolates of Salmonella (strain NZ CP014051 was taken as reference). Utilizing the subtractive proteomics approach on the Salmonella core proteome, Curlin major subunit A (CsgA) was selected as the vaccine candidate. csgA is a conserved gene that is related to biofilm formation. Immunodominant B and T cell epitopes from CsgA were predicted using numerous immunoinformatics tools. T lymphocyte epitopes had adequate population coverage and their corresponding MHC alleles showed significant binding scores after peptide-protein based molecular docking. Afterward, a multi-epitope vaccine was constructed with peptide linkers and Human Beta Defensin-2 (as an adjuvant). The vaccine could be highly antigenic, non-toxic, non-allergic, and have suitable physicochemical properties. Additionally, Molecular Dynamics Simulation and Immune Simulation demonstrated that the vaccine can bind with Toll Like Receptor 4 and elicit a robust immune response. Using in vitro, in vivo, and clinical trials, our findings could yield a Pan-Salmonella vaccine that might provide protection against various Salmonella species.
Topics: Proteomics; Epitopes, T-Lymphocyte; Salmonella; Computational Biology; Humans; Genomics; Molecular Docking Simulation; Salmonella Vaccines; Animals; Bacterial Proteins; Molecular Dynamics Simulation; Salmonella Infections; Epitopes, B-Lymphocyte; Immunoinformatics
PubMed: 38959229
DOI: 10.1371/journal.pone.0292413 -
PloS One 2024Children with under-five year age disproportionally affected with foodborne illness. Campylobacteriosis is the most common foodborne disease next to Norovirus infection....
Campylobacter jejuni and Campylobacter coli infection, determinants and antimicrobial resistance patterns among under-five children with diarrhea in Amhara National Regional State, Northwest Ethiopia.
BACKGROUND
Children with under-five year age disproportionally affected with foodborne illness. Campylobacteriosis is the most common foodborne disease next to Norovirus infection. Macrolides are commonly prescribed as the first line of treatment for Campylobacter gastroenteritis, with fluoroquinolone and tetracycline as secondary options. However, resistance to these alternatives has been reported in various regions worldwide.
OBJECTIVE
To determine the prevalence, associated risk-factors and antimicrobial resistance of Campylobacter jejuni and C. coli among under-five children with diarrhea.
METHODS
Institution-based cross-sectional study was conducted from November, 2022 to April 2023. The study sites were selected using a random sampling technique, while the study subjects were included using a convenient sampling technique. The data were collected using a structured questionnaire. Stool samples were inoculated onto modified charcoal cefoperazone deoxycholate agar and incubated for 48 hours. The suspected colonies were analyzed using matrix-assisted laser desorption ionization-time of flight mass spectrometry to confirm the species. Antimicrobial susceptibility testing was performed using a disc diffusion technique. All potential covariates (independent variables) were analyzed one by one using bivariate logistic regression model to identify candidate variables with P value < 0.25. Multivariable logistic analysis was used to identify potential associated factors using the candidate variables. A p value ≤ 0.05 at a 95% confidence interval was statistically significant.
RESULT
Among the 428 samples, 7.0% (CI: 4.5-9.3) were confirmed Campylobacter species. The prevalence of C. jejuni and C. coli among under-five children was 5.1% (CI: 3.0-7.0) and 1.9% (CI: 0.7-3.3), respectively. C. jejuni (73.3%) was dominant over C. coli (26.7%). The resident, contact with domestic animals, and parents/guardians education level were significantly associated with campylobacteriosis among under-five children. One-third of the Campylobacter isolates (33.3%, 10/30) were resistant to ciprofloxacin and tetracycline whereas 10.0% (3/30) were resistant to erythromycin. Furthermore, 3.3% (1/30) of the Campylobacter were found to be multidrug-resistant.
CONCLUSION
The prevalence of Campylobacter species was 7.0%. The resistance rate of Campylobacter species of ciprofloxacin and tetracycline-resistance strains was 33.3%. Peri-urban residence, contact with domestic animals, and low parental educational statuses were significantly associated factors with increased risk of Campylobacter infection. Continuous surveillance on antimicrobial resistance and health education of personal and environmental hygiene should be implemented in the community.
Topics: Humans; Campylobacter jejuni; Campylobacter coli; Campylobacter Infections; Child, Preschool; Infant; Female; Male; Diarrhea; Ethiopia; Cross-Sectional Studies; Anti-Bacterial Agents; Drug Resistance, Bacterial; Prevalence; Microbial Sensitivity Tests; Infant, Newborn; Risk Factors
PubMed: 38959220
DOI: 10.1371/journal.pone.0304409 -
ELife Jul 2024Bacterial exonuclease III (ExoIII), widely acknowledged for specifically targeting double-stranded DNA (dsDNA), has been documented as a DNA repair-associated nuclease...
Bacterial exonuclease III (ExoIII), widely acknowledged for specifically targeting double-stranded DNA (dsDNA), has been documented as a DNA repair-associated nuclease with apurinic/apyrimidinic (AP)-endonuclease and 3'→5' exonuclease activities. Due to these enzymatic properties, ExoIII has been broadly applied in molecular biosensors. Here, we demonstrate that ExoIII () possesses highly active enzymatic activities on ssDNA. By using a range of ssDNA fluorescence-quenching reporters and fluorophore-labeled probes coupled with mass spectrometry analysis, we found ExoIII cleaved the ssDNA at 5'-bond of phosphodiester from 3' to 5' end by both exonuclease and endonuclease activities. Additional point mutation analysis identified the critical residues for the ssDNase action of ExoIII and suggested the activity shared the same active center with the dsDNA-targeted activities of ExoIII. Notably, ExoIII could also digest the dsDNA structures containing 3'-end ssDNA. Considering most ExoIII-assisted molecular biosensors require the involvement of single-stranded DNA (ssDNA) or nucleic acid aptamer containing ssDNA, the activity will lead to low efficiency or false positive outcome. Our study revealed the multi-enzymatic activity and the underlying molecular mechanism of ExoIII on ssDNA, illuminating novel insights for understanding its biological roles in DNA repair and the rational design of ExoIII-ssDNA involved diagnostics.
Topics: Exodeoxyribonucleases; DNA, Single-Stranded; Escherichia coli; Escherichia coli Proteins
PubMed: 38959062
DOI: 10.7554/eLife.95648