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Journal of Water and Health Jun 2024We characterized concentrations of trihalomethanes (THMs), a measure of disinfection byproducts (DBPs), in tap water samples collected from households with...
We characterized concentrations of trihalomethanes (THMs), a measure of disinfection byproducts (DBPs), in tap water samples collected from households with utility-supplied water in two rural counties in Appalachian Virginia, and assessed associations with pH, free chlorine, and metal ions which can impact THM formation. Free chlorine concentrations in all samples ( = 27 homes) complied with EPA drinking water guidelines, though 7% ( = 2) of first draw samples and 11% ( = 3) of 5-min flushed-tap water samples exceeded the US Safe Drinking Water Act (SDWA) maximum contaminant level (MCL) for THM (80 ppb). Regression analyses showed that free chlorine and pH were positively associated with the formation of THM levels above SDWA MCLs (OR = 1.04, = 0.97 and OR = 1.74, = 0.79, respectively), while temperature was negatively associated (OR = 0.78, = 0.38). Of the eight utilities serving study households, samples from water served by three different utilities exceeded the EPA MCL for THM. Overall, these findings do not indicate substantial exposures to DBPs for rural households with utility-supplied water in this region of southwest Virginia. However, given the observed variability in THM concentrations between and across utilities, and established adverse health impacts associated with chronic and acute DBP exposure, more research on DBPs in rural Central Appalachia is warranted.
Topics: Virginia; Chlorine; Rural Population; Drinking Water; Water Pollutants, Chemical; Water Supply; Trihalomethanes; Water Purification; Disinfection; Humans; Disinfectants; Appalachian Region; Family Characteristics
PubMed: 38935457
DOI: 10.2166/wh.2024.054 -
European Endodontic Journal Jun 2024Evaluate the bacterial reduction effect of disinfection protocols used in lower molars infected by Enterococcus faecalis.
OBJECTIVE
Evaluate the bacterial reduction effect of disinfection protocols used in lower molars infected by Enterococcus faecalis.
METHODS
Eighty extracted lower molars were prepared and inoculated with E. faecalis for 2 months. The teeth were then distributed into 2 control groups (n = 4) and 4 experimental groups (n = 18) in function of the disinfection protocol utilized: G1. WaveOne Gold (WOG), passive ultrasonic irrigation (PUI) and Ultracal; G2. WOG, PUI and calcium hydroxide (CH); G3. WOG, XP-Endo Finisher (XPF) and Ultracal; G4. WOG, XPF and CH. Bacteriological samples were collected previously (S1), after preparation (S2), final agitation (S3) and intracanal dressing (S4). Microbial growth was assessed according to culture turbidity and UV spectrophotometry. Statistical analyses used the Friedman test for paired samples and Kruskal-Wallis test for non-paired data (p<0.05).
RESULTS
No protocol eliminated E. faecalis effectively. The S2, S3 and S4 samples were statistically different from the S1 samples in G1, G2, G3 and G4 (p<0.05). Statistical differences were observed in bacterial reduction between G1 and G2 and G1 and G3 after the intracanal medicament (S4) (p<0.05).
CONCLUSION
The WOG + PUI + CH disinfection protocol showed higher percentages of bacterial reduction.
PubMed: 38935107
DOI: 10.14744/hnhj.2024.47450 -
Indian Journal of Public Health Oct 2023The augmentation of precautionary behaviors through the application of health belief model (HBM) constructs could help in curbing the current pandemic.
BACKGROUND
The augmentation of precautionary behaviors through the application of health belief model (HBM) constructs could help in curbing the current pandemic.
OBJECTIVES
The objectives are to assess adherence to CAB and to evaluate its predictors using the constructs of HBM among COVID-19 vaccinees in Himachal Pradesh.
MATERIALS AND METHODS
A cross-sectional study using a telephone survey, with two-step stratified random sampling, was employed to acquire a sample of 441 respondents from Himachal Pradesh. Formal interviews were conducted using pretested, structured, self-administered questionnaires.
RESULTS
The mean age of respondents was 32.16 years (standard deviation = 12.77; range = 18-78 years). Maximum adherence was seen for wearing masks at 83% (95% confidence interval [CI]: 79.3%-86.3%), followed by maintenance of respiratory hygiene at 72.3% (95% CI 68%-78.4%). Nearly 42.2% (95% CI 37.6%-47.8%) conformed to social distancing norms. We observed minimum adherence for handwashing practices of 12.9% (95% CI 10%-16.3.0%). On bivariate analyses, except for perceived severity, all HBM constructs were significantly associated with CAB. However, after adjusting for gender, age, education, area of residence, and reduced income in multivariate analysis, perceived susceptibility, perceived barriers, and exposure to cues to action remained significant predictors of CAB.
CONCLUSIONS
The study highlights the empirical evidence of the application of HBM constructs to enhance behavioral adherence to COVID-19 precautionary measures.
Topics: Humans; COVID-19; India; Adult; Cross-Sectional Studies; Male; Female; Middle Aged; Health Belief Model; Adolescent; Young Adult; Aged; SARS-CoV-2; Health Behavior; Health Knowledge, Attitudes, Practice; Socioeconomic Factors; Hand Disinfection
PubMed: 38934832
DOI: 10.4103/ijph.ijph_1525_22 -
ACS Catalysis May 2024Electrochemical ozone production (EOP), a six-electron water oxidation reaction, offers promising avenues for creating value-added oxidants and disinfectants. However,...
Electrochemical ozone production (EOP), a six-electron water oxidation reaction, offers promising avenues for creating value-added oxidants and disinfectants. However, progress in this field is slowed by a dearth of understanding of fundamental reaction mechanisms. In this work, we combine experimental electrochemistry, spectroscopic detection of reactive oxygen species (ROS), oxygen-anion chemical ionization mass spectrometry, and computational quantum chemistry calculations to determine a plausible reaction mechanism on nickel- and antimony-doped tin oxide (Ni/Sb-SnO, NATO), one of the most selective EOP catalysts. Antimony doping is shown to increase the conductivity of the catalyst, leading to improved electrochemical performance. Spectroscopic analysis and electrochemical experiments combined with quantum chemistry predictions reveal that hydrogen peroxide (HO) is a critical reaction intermediate. We propose that leached Ni cations catalyze hydrogen peroxide into solution phase hydroperoxyl radicals (OOH); these radicals are subsequently oxidized to ozone. Isotopic product analysis shows that ozone is generated catalytically from water and corrosively from the catalyst oxide lattice without regeneration of lattice oxygens. Further quantum chemistry calculations and thermodynamic analysis suggest that the electrochemical corrosion of tin oxide itself might generate hydrogen peroxide, which is then catalyzed to ozone. The proposed pathways explain both the roles of dopants in NATO and its lack of stability. Our study interrogates the possibility that instability and electrochemical activity are intrinsically linked through the formation of ROS. In doing so, we provide the first mechanism for EOP that is consistent with computational and experimental results and highlight the central challenge of instability as a target for future research efforts.
PubMed: 38933735
DOI: 10.1021/acscatal.4c01317 -
Fundamental Research May 2024Land public transport is an important link within and between cities, and how to control the transmission of COVID-19 in land public transport is a critical issue in our... (Review)
Review
Land public transport is an important link within and between cities, and how to control the transmission of COVID-19 in land public transport is a critical issue in our daily lives. However, there are still many inconsistent opinions and views about the spread of SARS-CoV-2 in land public transport, which limits our ability to implement effective interventions. The purpose of this review is to overview the literature on transmission characteristics and routes of the epidemic in land public transport, as well as to investigate factors affecting its spread and provide feasible measures to mitigate the infection risk of passengers. We obtained 898 papers by searching the Web of Science, Pubmed, and WHO global COVID database by keywords, and finally selected 45 papers that can address the purpose of this review. Land public transport is a high outbreak area for COVID-19 due to characteristics like crowding, inadequate ventilation, long exposure time, and environmental closure. Different from surface touch transmission and drop spray transmission, aerosol inhalation transmission can occur not only in short distances but also in long distances. Insufficient ventilation is the most important factor influencing long-distance aerosol transmission. Other transmission factors (e.g., interpersonal distance, relative orientation, and ambient conditions) should be noticed as well, which have been summarized in this paper. To address various influencing factors, it is essential to suggest practical and efficient preventive measures. Among these, increased ventilation, particularly the fresh air (i.e., natural ventilation), has proven to effectively reduce indoor infection risk. Many preventive measures are also effective, such as enlarging social distance, avoiding face-to-face orientation, setting up physical partitions, disinfection, avoiding talking, and so on. As research on the epidemic has intensified, people have broken down many perceived barriers, but more comprehensive studies on monitoring systems and prevention measures in land public transport are still needed.
PubMed: 38933205
DOI: 10.1016/j.fmre.2023.10.013 -
Frontiers in Microbiology 2024The global rise in antimicrobial resistance (AMR) poses a significant public health threat, especially in healthcare settings, where controlling the spread of... (Review)
Review
The global rise in antimicrobial resistance (AMR) poses a significant public health threat, especially in healthcare settings, where controlling the spread of antimicrobial genes is crucial. While person-to-person transmission remains the primary route for healthcare-associated infections (HAIs), hospital surfaces serve as key reservoirs for antimicrobial-resistant microorganisms. Regular cleaning and disinfection of these surfaces are essential. Microbial-based products for sanitizing hospital surfaces have emerged as promising tools to combat HAIs and AMR. However, a review of 32 publications found inconsistencies and potential risks. A total of 15 publications included hospital-based trials, while the rest were either or assays, reviews, book chapters, or commentaries. In most of the hospital-based studies, specific strains of applied microorganisms were not identified, and the term "probiotic" was inaccurately used. These products mainly featured spores from and genera, which was mainly hypothesized to work through competitive exclusion. Most hospital-based studies have shown that the application of microbial-based products resulted in a significant reduction in pathogens on surfaces, thereby contributing to a decrease in the incidence of healthcare-associated infections (HAIs). Further research is however needed to understand the effectiveness, mechanisms of action, and safety of microbial-based sanitizing agents. Strain-level identification is crucial for safety assessments, yet many reviewed products lacked this information. Consequently, there is a need for rigorous safety evaluations within existing regulatory frameworks to ensure the efficacy and safety of microbial-based cleaning products in healthcare settings.
PubMed: 38933019
DOI: 10.3389/fmicb.2024.1412269 -
Polymers Jun 2024Regenerative endodontics is a developing field involving the restoration of tooth structure and re-vitality of necrotic pulp. One of the most critical clinical...
Regenerative endodontics is a developing field involving the restoration of tooth structure and re-vitality of necrotic pulp. One of the most critical clinical considerations for regenerative endodontic procedures is the disinfection of the root canal system, since infection interferes with regeneration, repair, and stem cell activity. In this study, we aimed to provide the synthesis of injectable biopolymeric tissue scaffolds that can be used in routine clinical and regenerative endodontic treatment procedures using Gelatin methacryloyl (GelMA), and to test the antimicrobial efficacy of Gelatin methacryloyl/Silver nanoparticles (GelMA/AgNP), Gelatin methacryloyl/Hyaluronic acid (GelMA/HYA), and Gelatin methacryloyl/hydroxyapatite (GelMA/HA) composite hydrogels against microorganisms that are often encountered in stubborn infections in endodontic microbiology. Injectable biocomposite hydrogels exhibiting effective antimicrobial activity and non-cytotoxic behavior were successfully synthesized. This is also promising for clinical applications of regenerative endodontic procedures with hydrogels, which are proposed based on the collected data. The GelMA hydrogel loaded with hyaluronic acid showed the highest efficacy against , one of the stubborn bacteria in the root canal. The GelMA hydrogel loaded with hydroxyapatite also showed a significant effect against , which is another bacteria responsible for stubborn infections in the root canal.
PubMed: 38932026
DOI: 10.3390/polym16121675 -
Nutrients Jun 2024The use of natural products as alternatives to traditional pharmacological treatments in orthodontics is gaining interest due to their anti-inflammatory, antibacterial,... (Review)
Review
The use of natural products as alternatives to traditional pharmacological treatments in orthodontics is gaining interest due to their anti-inflammatory, antibacterial, and antioxidant properties. This systematic review synthesizes evidence from clinical trials to evaluate the efficacy of natural products in reducing inflammation and bacterial presence in orthodontic and orthognathic treatment settings. The database search was conducted across PubMed, Scopus, and Embase up to January 2024. The review focused on randomized controlled trials only. The selected studies centered on the anti-inflammatory, antibacterial, and antioxidant effects of natural products, adhering to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines for data extraction. Nine studies, totaling 358 participants, were included. Significant findings demonstrated a reduction in gingival inflammation by over 40% with the use of Aloe vera compared to chlorhexidine. Another study noted a decrease in bleeding on probing by 13.6 points in the treatment group over placebo. Additionally, honey showed a rapid modulation of plaque pH and significantly reduced bacterial counts of . Furthermore, the use of resveratrol emulgel was linked to substantial improvements in gingival health, with a reduction in the gingival index and probing pocket depth. The results indicate that natural products can significantly enhance orthodontic treatment outcomes by reducing inflammation and bacterial levels. These products offer effective alternatives to traditional treatments and show potential for integration into routine orthodontic care protocols. Further research is encouraged to standardize application methods and dosages to maximize clinical benefits and patient satisfaction.
Topics: Humans; Aloe; Anti-Bacterial Agents; Anti-Inflammatory Agents; Antioxidants; Biological Products; Chlorhexidine; Dentofacial Deformities; Gingivitis; Honey; Orthodontics; Plant Preparations; Randomized Controlled Trials as Topic; Resveratrol; Streptococcus mutans; Treatment Outcome
PubMed: 38931295
DOI: 10.3390/nu16121941 -
Plants (Basel, Switzerland) Jun 2024is a Gram-positive bacteria with the greatest impact in the clinical area, due to the high rate of infections and deaths reaching every year. A previous scenario is...
is a Gram-positive bacteria with the greatest impact in the clinical area, due to the high rate of infections and deaths reaching every year. A previous scenario is associated with the bacteria's ability to develop resistance against conventional antibiotic therapies as well as biofilm formation. The above situation exhibits the necessity to reach new effective strategies against this pathogen. is a medicinal plant commonly used for bacterial infections treatments and has demonstrated antimicrobial effect, although its effect against and bacterial biofilms has not been investigated. The purpose of this work was to analyze the antimicrobial and antibiofilm potential of against . The antimicrobial effect was determined using an ethanolic extract of . The surface charge of the bacterial membrane, the K leakage and the effect on motility were determined. The ability to prevent and remove bacterial biofilms was analyzed in terms of bacterial biomass, metabolic activity and viability. The results showed that presents inhibitory (MIC: 250 µg/mL) and bactericidal (MBC: 500 µg/mL) activity against . The MIC extract increased the bacterial surface charge by 1.4 times and the K concentration in the extracellular medium by 60%. The MIC extract inhibited the motility process by 100%, 61% and 40% after 24, 48 and 72 h, respectively. The MIC extract prevented the formation of biofilms by more than 80% in terms of biomass production and metabolic activity. An extract at 10 × MIC reduced the metabolic activity by 82% and the viability by ≈50% in preformed biofilms. The results suggest that affects membrane and the process of biofilm formation and removal. This effect could set a precedent to use this plant as alternative for antimicrobial and disinfectant therapies to control infections caused by this pathogen. In addition, this shrub could be considered for carrying out a purification process in order to identify the compounds responsible for the antimicrobial and antibiofilm effect.
PubMed: 38931103
DOI: 10.3390/plants13121671 -
Microorganisms Jun 2024Edible fungi are a valuable resource in the search for sustainable solutions to environmental pollution. Their ability to degrade organic pollutants, extract heavy...
Edible fungi are a valuable resource in the search for sustainable solutions to environmental pollution. Their ability to degrade organic pollutants, extract heavy metals, and restore ecological balance has a huge potential for bioremediation. They are also sustainable food resources. Edible fungi (basidiomycetes or fungi from other divisions) represent an underutilized resource in the field of bioremediation. By maximizing their unique capabilities, it is possible to develop innovative approaches for addressing environmental contamination. The aim of the present study was to find selective chemical agents suppressing the growth of microfungi and bacteria, but not suppressing white-rot fungi, in order to perform large-scale cultivation of white-rot fungi in natural unsterile substrates and use it for different purposes. One application could be the preparation of a matrix composed of wooden sleeper (contaminated with PAHs) and soil for further hazardous waste bioremediation using white-rot fungi. In vitro microbiological methods were applied, such as, firstly, compatibility tests between bacteria and white-rot fungi or microfungi, allowing us to evaluate the interaction between different organisms, and secondly, the addition of chemicals on the surface of a Petri dish with a test strain of microorganisms of white-rot fungi, allowing us to determine the impact of chemicals on the growth of organisms. This study shows that white-rot fungi are not compatible to grow with several rhizobacteria or bacteria isolated from soil and bioremediated waste. Therefore, the impact of several inorganic materials, such as lime (hydrated form), charcoal, dolomite powder, ash, gypsum, phosphogypsum, hydrogen peroxide, potassium permanganate, and sodium hydroxide, was evaluated on the growth of microfungi (sixteen strains), white-rot fungi (three strains), and bacteria (nine strains) . Charcoal, dolomite powder, gypsum, and phosphogypsum did not suppress the growth either of microfungi or of bacteria in the tested substrate, and even acted as promoters of their growth. The effects of the other agents tested were strain dependent. Potassium permanganate could be used for bacteria and spp. growth suppression, but not for other microfungi. Lime showed promising results by suppressing the growth of microfungi and bacteria, but it also suppressed the growth of white-rot fungi. Hydrogen peroxide showed strong suppression of microfungi, and even had a bactericidal effect on some bacteria, but did not have an impact on white-rot fungi. The study highlights the practical utility of using hydrogen peroxide up to 3% as an effective biota-suppressing chemical agent prior to inoculating white-rot fungi in the large-scale bioremediation of polluted substrates, or in the large-scale cultivation for mushroom production as a foodstuff.
PubMed: 38930624
DOI: 10.3390/microorganisms12061242