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1.
Sci Total Environ ; 949: 175079, 2024 Nov 01.
Article in English | MEDLINE | ID: mdl-39094658

ABSTRACT

Extended-spectrum ß-lactamases (ESBLs)-producing E. coli have been proposed as an indicator bacterium for antimicrobial resistance (AMR) surveillance within a OneHealth framework. However, it is important to understand the effects and potential biases ESBL-selection has on E. coli populations. Utilising whole genome sequencing, this study compared 80 ESBL-selected E. coli isolates with 201 non-selected isolates from Australian wastewater. The findings revealed significant variations between these cohorts in genetic diversity, AMR profiles, and carriage of virulence-associated genes (VAGs), plasmids, and the transmissible Locus of Stress Tolerance (tLST), a genomic island that imparts resistance to extreme heat and chlorination. The study highlights the predominance of certain sequence types (STs), particularly ST131 (75 % clade A), in ESBL-selected isolates (40 % vs 2 %) and overall the ESBL-selected isolates were largely multidrug-resistant (MDR), predominantly carrying genes for resistance to aminoglycosides, extended-spectrum ß-lactams, fluoroquinolone, macrolides, sulphonamides/trimethoprim, and tetracyclines. The ESBLs identified were almost exclusively blaCTX-M genes, most commonly blaCTX-M-15 > blaCTX-M-27 > blaCTX-M-14. These were predominately carried on IncF plasmids or chromosomally (always ISEcp1 associated), in equal numbers. In contrast, 80 % of non-selected isolates carried no acquired ARGs, and none carried blaCTX-M genes. In both cohorts, extraintestinal pathogenic E. coli (ExPEC) was the dominate pathotype (35 % total) with few (4 % total) intestinal pathogenic E. coli pathotypes identified (aEPEC > ETEC > EAEC). Nevertheless, some clinically important genes were only identified in the non-selected group, namely tigecycline-resistance gene tet(X4) and AmpC ESBL blaCMY-2. Additionally, the presence of tLST, associated with higher metal resistance gene carriage (Ag, As, Cu, Hg, Ni), in a substantial portion of non-selected isolates (20 % vs 0 %), underscores environmental pressures shaping bacterial populations in wastewater ecosystems. These insights are important for developing comprehensive, less biased genomic surveillance strategies to understand and manage public health threats posed by pathogenic E. coli and AMR.


Subject(s)
Escherichia coli , Wastewater , beta-Lactamases , Escherichia coli/genetics , Escherichia coli/drug effects , Wastewater/microbiology , Australia , beta-Lactamases/genetics , Virulence/genetics , Anti-Bacterial Agents/pharmacology , Genomics , Drug Resistance, Bacterial/genetics
2.
Georgian Med News ; (349): 68-71, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38963204

ABSTRACT

Hyperuricemia is an objective risk factor of derangement of fasting serum glucose and type 2 diabetes (T2D), yet whether hyperuricemia has a causative influence on insulin resistance is still debatable. In this study, we tested the hypothesis that lowering uric acid in hyperuricemic nondiabetic subjects might improve insulin resistance. Patients with renal stone and hyperuricemia (n=15) were recruited from the private clinic of Ib-Sina Local Teaching Hospital in Mosul city and prospectively placed on allopurinol (300mg/day) for 6 months. Serum uric acid (SUA), fasting serum glucose (FSG), fasting insulin, and C-peptide were measured using commercial kits. Results confirmed that allopurinol has significantly (P<0.05) reduced c-peptide and insulin together with a non-significant (p>0.05) reduction of serum glucose levels. In conclusion, allopurinol has improved insulin level and glycemic control in a healthy individual, these findings could be used as a template for using allopurinol in diabetic patients to improve glycemic control or future studies could be directed toward structural modification of allopurinol which hopefully might lead to innovation of new antidiabetic drugs.


Subject(s)
Allopurinol , Blood Glucose , Hyperuricemia , Insulin Resistance , Insulin , Kidney Calculi , Uric Acid , Humans , Allopurinol/therapeutic use , Kidney Calculi/drug therapy , Uric Acid/blood , Insulin/blood , Male , Blood Glucose/drug effects , Blood Glucose/metabolism , Middle Aged , Hyperuricemia/drug therapy , Hyperuricemia/blood , Hyperuricemia/complications , Female , Adult , C-Peptide/blood , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/blood
3.
Waste Manag ; 185: 1-9, 2024 Jul 30.
Article in English | MEDLINE | ID: mdl-38815529

ABSTRACT

Quality assurance of a recycled product is currently one of the biggest issues that the plastic recycling industry faces. The purity of the input plastic waste stream has significant influence over the quality of the recycled product. This research evaluated the impact of polylactic acid (PLA) contamination within the input waste stream of high-density polyethylene (HDPE) recycling. The ultimate tensile strength was noted to reduce by 50% when PLA contamination was at 10%. An investigation into the effect that UVA radiation (simulating solar radiation) has on HDPE contaminated with PLA was also performed to determine the long-term effect of the bioplastic contamination. After UVA treatment, the ultimate tensile strength was reported to reduce by 51% when PLA contamination was only at 2.5%. A water contact angle analysis indicated the PLA contamination increased the hydrophilic nature of the HDPE sheets, potentially creating issues if the intended use of the recycled product was to store liquids. Microscopic analysis of the HDPE sheets contaminated with PLA showed deformations, ridges, cracks, and holes appear on the surface due to the immiscibility of the two polymers that was confirmed by FTIR analysis. Colour changes were visibly noted, with UVA exposure increasing the rate of colour change. Based on the findings in this study, PLA contamination of even 1% in a HDPE waste stream would significantly reduce the quality of the recycled product.


Subject(s)
Plastics , Polyesters , Recycling , Recycling/methods , Polyethylene/chemistry , Ultraviolet Rays , Tensile Strength
4.
Science ; 383(6686): 958, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38422149
5.
Water Res ; 251: 121101, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38218072

ABSTRACT

Stormwater can carry pollutants accumulated on impervious surfaces in urban areas into natural water bodies in absence of stormwater quality improvement devices. Pervious concrete (PC) pavement is one of the low-impact development practices introduced for urban flooding prevention and stormwater pollution reduction. PC removes various types of water contaminants. Mechanisms contributing to the water pollution removal capacity of PC can be categorized into three groups: physical, chemical, and biological. Properties of PC such as permeability, porosity, thickness, and adsorption capacity influence removal of all contaminants, although their impact might differ depending on the pollutant properties. Chemical mechanisms include precipitation, co-precipitation, ion and ligand exchange, complexation, diffusion, and sorption. Bulk organics and nutrients are removed primarily by biodegradation. Physical filtration is the primary mechanism to retain suspended solids, although biological activities may have a minor contribution. Release of calcium (Ca2+) and hydroxide (OH-) from hardened cement elevates the effluent pH, which is an environmental concern. However, the pH elevation is also the prime contributor to heavy metals and nutrients removal through precipitation. Specific cementitious materials (e.g., Pozzolans and nanoparticles) and carbonation curing approach are recommended to control effluent pH elevation. Complexation, diffusion, ion solubility, and stability constants are other mechanisms and parameters that influence heavy metal removal. Organic matter availability, electrostatic attraction, temperature, pH, contact time, specific surface area, and roughness of PC pores contribute to the pathogen removal process. Although PC has been found promising in removing various water pollutants, limited salinity removal can be achieved due to the inherent release of Ca2+and OH- from PC.


Subject(s)
Metals, Heavy , Water Pollutants, Chemical , Rain , Metals, Heavy/chemistry , Water Pollution , Calcium , Water Pollutants, Chemical/chemistry , Water
6.
Commun Biol ; 7(1): 66, 2024 01 09.
Article in English | MEDLINE | ID: mdl-38195839

ABSTRACT

Higher birth order is associated with altered risk of many disease states. Changes in placentation and exposures to in utero growth factors with successive pregnancies may impact later life disease risk via persistent DNA methylation alterations. We investigated birth order with Illumina DNA methylation array data in each of 16 birth cohorts (8164 newborns) with European, African, and Latino ancestries from the Pregnancy and Childhood Epigenetics Consortium. Meta-analyzed data demonstrated systematic DNA methylation variation in 341 CpGs (FDR adjusted P < 0.05) and 1107 regions. Forty CpGs were located within known quantitative trait loci for gene expression traits in blood, and trait enrichment analysis suggested a strong association with immune-related, transcriptional control, and blood pressure regulation phenotypes. Decreasing fertility rates worldwide with the concomitant increased proportion of first-born children highlights a potential reflection of birth order-related epigenomic states on changing disease incidence trends.


Subject(s)
Birth Order , DNA Methylation , Child , Female , Humans , Infant, Newborn , Pregnancy , Epigenesis, Genetic , Epigenomics
7.
Chemosphere ; 350: 140978, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38135125

ABSTRACT

In this study, the performance of standalone ultraviolet (UV) photolysis and UV-based advanced oxidation processes (AOPs), namely, UV/hydrogen peroxide, UV/chlorine, UV/persulphate, and UV/permonosulphate, were investigated for the degradation of 31 trace organic contaminants (TrOCs). Under the tested conditions, standalone UV photolysis did not achieve effective removal of TrOCs. To improve the degradation efficiency of UV photolysis, four different oxidants were added individually to the test solution. The effect of these oxidants in the absence of UV irradiation was also explored and only chlorine showed promising degradation of some contaminants. During the chlorination of 31 investigated TrOCs, only six demonstrated greater than 50% degradation. The combined UV-based AOPs demonstrated much improved degradation (ranging from 65 to 100%) depending on TrOC-structure and oxidant concentration. The UV/hydrogen peroxide process showed similar degradation of TrOCs, irrespective of the functional groups (i.e., electron withdrawing groups, EWGs and electron donating groups, EDGs) present in their structures. Conversely, the UV/sulphate and UV/chlorine based processes achieved better degradation of the TrOCs with EDGs in their structures. TrOCs degradation improved up to 40% when oxidants concentrations were increased from 0.1 to 1 mM, and further increasing the concentration to 2 mM did not improve degradation. Toxicity evaluation using bioluminescence test (BLT assay) demonstrated that except for UV/hydrogen peroxide, all UV-based AOPs increased the toxicity of the treated effluent, indicating generation of toxic by-products. This study elucidates the performance of four different UV-based AOPs for the removal of commonly detected diverse TrOCs for the first time.


Subject(s)
Water Pollutants, Chemical , Water Purification , Hydrogen Peroxide/chemistry , Chlorine , Water Pollutants, Chemical/analysis , Oxidants , Oxidation-Reduction , Photolysis , Ultraviolet Rays
8.
Curr Rheumatol Rev ; 2023 Nov 07.
Article in English | MEDLINE | ID: mdl-37957845

ABSTRACT

PURPOSE: Osteoarthritis and other joint disorders are the leading cause of disability in the elderly and the treatment of joint lesions is challenging. Autologous chondrocyte implantation (ACI) has been reported with variable effects for the treatment of osteochondral and other joint lesions. In this study, we performed a meta-analysis of the recent literature to determine the clinical applicability of ACI for osteochondral defects. METHODS: A meta-analysis was performed on the recent literature showing the effects of ACI on osteochondral defects. The PUBMED, ScienceDirect and Google Scholar databases were used to identify eligible studies from Jan 2010 to Sep 2022. Both fixed and random models of meta-analysis were applied with all reported scoring systems to quantify the effectiveness of ACI on osteochondral defects. RESULTS: The pool data of 965 patients as a case series after ACI from a fixed model showed a significant improvement in the osteochondral defects (odds ratio = 8.75, 95%CI = 7.127 to 10.743, p = 0.000). These results were further verified by a random model of meta-analysis. The data also showed a substantial heterogeneity among the studies used in the meta-analysis (Q-value = 160.41, I-squared = 87.53, p = 0.000). Furthermore, this meta-analysis also compared different ACI procedures with different scoring systems but the overall outcome remains the same as ACI was found to be useful for the healing of the osteochondral defects. CONCLUSION: This meta-analysis of 965 case series revealed that the ACI markedly improved the damage osteochondral defects scores but the optimal treatment is still controversial, therefore further studies are needed to validate these findings in a clinical setting. REGISTRATION: This meta-analysis has been submitted to the National Institute for Health and Care Research (NIHCR), PROSPERO for registration with an application # ID 365014.

9.
Cureus ; 15(9): e45447, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37859891

ABSTRACT

Objectives The objectives of this study were to measure the prevalence of social anxiety disorder and its association with quality of life (QoL) in patients with epilepsy (PWE) in King Khalid University Hospital, Riyadh City, Saudi Arabia. Methodology A self-administrated, online, questionnaire-based, cross-sectional study was conducted at King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia on PWE 18 years of age and above from February 2021 to January 2022. Social anxiety and the five domains of QoL were measured using the validated Arabic versions of the Liebowitz social anxiety scale and European quality-of-life 5-dimensions 3-levels (EQ-5D-3L), respectively. Information was collected on sociodemographic characteristics, social support, and adverse life events. Results This study included 246 patients, of which approximately 25% and 15% had mild/moderate and severe/very severe levels of social anxiety, respectively. Severe social anxiety was significantly associated with poor QoL domains, namely, restricted mobility (2.65 [1.00, 6.99]), inability to perform usual activities (3.88 [1.61, 9.36]), pain or discomfort (3.21 [1.38, 7.48]), and anxiety and depression (5.77 [2.45, 13.61]). Similarly, the lack of social support was also significantly associated with poor QoL, such as restricted mobility (2.42 [1.12, 5.22]), restricted self-care (3.64 [1.18, 11.17]), inability to perform usual activities (2.86 [1.42, 5.75]), pain/discomfort (2.53 [1.38, 4.66]), and anxiety and depression (1.93 [1.04, 3.57]). Females showed higher odds for restricted mobility (2.79 [1.29, 6.03]) and low education with limited self-care (7.38 [1.49, 36.71]). Conclusion Patients with epilepsy reported high levels of social anxiety that have a negative effect on their QoL. Healthcare providers should be able to provide counseling to the patient and their family members. In addition, social support is important to improve their mobility and socialization with friends and neighbors.

10.
Clin Epigenetics ; 15(1): 131, 2023 08 31.
Article in English | MEDLINE | ID: mdl-37649101

ABSTRACT

BACKGROUND: Experimental studies suggest that exposures may impact respiratory health across generations via epigenetic changes transmitted specifically through male germ cells. Studies in humans are, however, limited. We aim to identify epigenetic marks in offspring associated with father's preconception smoking. METHODS: We conducted epigenome-wide association studies (EWAS) in the RHINESSA cohort (7-50 years) on father's any preconception smoking (n = 875 offspring) and father's pubertal onset smoking < 15 years (n = 304), using Infinium MethylationEPIC Beadchip arrays, adjusting for offspring age, own smoking and maternal smoking. EWAS of maternal and offspring personal smoking were performed for comparison. Father's smoking-associated dmCpGs were checked in subpopulations of offspring who reported no personal smoking and no maternal smoking exposure. RESULTS: Father's smoking commencing preconception was associated with methylation of blood DNA in offspring at two cytosine-phosphate-guanine sites (CpGs) (false discovery rate (FDR) < 0.05) in PRR5 and CENPP. Father's pubertal onset smoking was associated with 19 CpGs (FDR < 0.05) mapped to 14 genes (TLR9, DNTT, FAM53B, NCAPG2, PSTPIP2, MBIP, C2orf39, NTRK2, DNAJC14, CDO1, PRAP1, TPCN1, IRS1 and CSF1R). These differentially methylated sites were hypermethylated and associated with promoter regions capable of gene silencing. Some of these sites were associated with offspring outcomes in this cohort including ever-asthma (NTRK2), ever-wheezing (DNAJC14, TPCN1), weight (FAM53B, NTRK2) and BMI (FAM53B, NTRK2) (p < 0.05). Pathway analysis showed enrichment for gene ontology pathways including regulation of gene expression, inflammation and innate immune responses. Father's smoking-associated sites did not overlap with dmCpGs identified in EWAS of personal and maternal smoking (FDR < 0.05), and all sites remained significant (p < 0.05) in analyses of offspring with no personal smoking and no maternal smoking exposure. CONCLUSION: Father's preconception smoking, particularly in puberty, is associated with offspring DNA methylation, providing evidence that epigenetic mechanisms may underlie epidemiological observations that pubertal paternal smoking increases risk of offspring asthma, low lung function and obesity.


Subject(s)
Asthma , DNA Methylation , Male , Humans , Smoking/adverse effects , Smoking/genetics , Tobacco Smoking , Epigenesis, Genetic , Cytosine , Guanine , Chromosomal Proteins, Non-Histone
11.
Allergy ; 78(10): 2623-2643, 2023 10.
Article in English | MEDLINE | ID: mdl-37584170

ABSTRACT

The field of medicine is witnessing an exponential growth of interest in artificial intelligence (AI), which enables new research questions and the analysis of larger and new types of data. Nevertheless, applications that go beyond proof of concepts and deliver clinical value remain rare, especially in the field of allergy. This narrative review provides a fundamental understanding of the core concepts of AI and critically discusses its limitations and open challenges, such as data availability and bias, along with potential directions to surmount them. We provide a conceptual framework to structure AI applications within this field and discuss forefront case examples. Most of these applications of AI and machine learning in allergy concern supervised learning and unsupervised clustering, with a strong emphasis on diagnosis and subtyping. A perspective is shared on guidelines for good AI practice to guide readers in applying it effectively and safely, along with prospects of field advancement and initiatives to increase clinical impact. We anticipate that AI can further deepen our knowledge of disease mechanisms and contribute to precision medicine in allergy.


Subject(s)
Artificial Intelligence , Hypersensitivity , Humans , Machine Learning , Precision Medicine , Hypersensitivity/diagnosis , Hypersensitivity/therapy
12.
Sci Total Environ ; 903: 166082, 2023 Dec 10.
Article in English | MEDLINE | ID: mdl-37544438

ABSTRACT

Microbial electrochemical technologies are promising for simultaneous energy recovery and wastewater treatment. Although the inhibitory effects of emerging pollutants, particularly micro/nanoplastics (MPs/NPs), on conventional wastewater systems have been extensively studied, the current understanding of their impact on microbial electrochemical systems is still quite limited. Microplastics are plastic particles ranging from 1 µm to 5 mm. However, nanoplastics are smaller plastic particles ranging from 1 to 100 nm. Due to their smaller size and greater surface area, they can penetrate deeper into biofilm structures and cell membranes, potentially disrupting their integrity and leading to changes in biofilm composition and function. This study first reports the impact of polystyrene nanoplastics (PsNPs) on syntrophic anode microbial communities in a microbial electrolysis cell. Low concentrations of PsNPs (50 and 250 µg/L) had a minimal impact on current density and hydrogen production. However, 500 µg/L of PsNPs decreased the maximum current density and specific hydrogen production rate by ∼43 % and ∼48 %, respectively. Exposure to PsNPs increased extracellular polymeric substance (EPS) levels, with a higher ratio of carbohydrates to proteins, suggesting a potential defense mechanism through EPS secretion. The downregulation of genes associated with extracellular electron transfer was observed at 500 µg/L of PsNPs. Furthermore, the detrimental impact of 500 µg/L PsNPs on the microbiome was evident from the decrease in 16S rRNA gene copies, microbial diversity, richness, and relative abundances of key electroactive and fermentative bacteria. For the first time, this study presents the inhibitory threshold of any NPs on syntrophic electroactive biofilms within a microbial electrochemical system.

13.
Sci Total Environ ; 902: 166090, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-37553052

ABSTRACT

This study casts light on the potential of microplastic generation during plastic recycling - an unintended consequence of the process. To date, microplastics have been detected in the wastewater and sludge from plastic recycling facilities; however, generation pathways, factors and minimisation strategies are understudied. The purpose of this study is to identify the factors affecting microplastic generation, namely, plastic type and weathering conditions. The size reduction phase, which involved the mechanical shredding of the plastic waste material, was identified to be the predominate source of microplastic generation. Material type was found to significantly affect microplastic generation rates. Focussing on the microplastic particles in the size range of 0.212-1.18 mm, polycarbonate (PC), polyethylene terephthalate (PET), polypropylene (PP), and high-density polyethylene (HDPE) generated 28,600 ± 3961, 21,093 ± 2211, 18,987 ± 752 and 6807 ± 393 particles/kg of plastic material shredded, respectively. The significant variations between different plastic types were correlated (R2 = 0.88) to the hardness of the plastic. Environmental weathering was observed to significantly affect microplastic generation rates. Generation rates increased for PC, PET, PP, and HDPE by 185.05 %, 159.80 %, 123.70 % and 121.74 %, respectively, over a six-month environmental exposure period. The results in this study confirm production of large amounts of microplastics from the plastic recycling industry through its operational processes, which may be a significant source for microplastic pollution if measures to reduce their production and removal from wastewater and sludge are not considered.

14.
Bioengineered ; 14(1): 2244754, 2023 12.
Article in English | MEDLINE | ID: mdl-37553794

ABSTRACT

Over the years, it has become evident that microplastics are one of the most important contaminants of concern requiring significant attention. The large abundance of microplastics that are currently in the environment poses potential toxicity risks to all organisms that are exposed to them. Microplastics have been found to affect the physiological and biological processes in marine and terrestrial organisms. As well as being a contaminant of concern in itself, microplastics also have the ability to act as vectors for other contaminants. The potential for microplastics to carry pollutants and transfer them to other organisms has been documented in the literature. Microplastics have also been linked to hosting antibiotic resistant bacteria and antibiotic resistance genes which poses a significant risk to the current health system. There has been a significant increase in research published surrounding the topic of microplastics over the last 5 years. As such, it is difficult to determine and find up to date and relevant information. This overview paper aims to provide a snapshot of the current and emerging sources of microplastics, how microplastics can act as a contaminant and have toxic effects on a range of organisms and also be a vector for a large variety of other contaminants of concern. The aim of this paper is to act as a tool for future research to reference relevant and recent literature in this field.


Subject(s)
Microplastics , Microplastics/chemistry , Humans , Environmental Pollutants/chemistry , Bibliometrics , Environmental Monitoring
15.
Ann Med Surg (Lond) ; 85(7): 3446-3460, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37427236

ABSTRACT

Computer-aided drug design by molecular docking, statistical analysis like multiple linear regression (MLR), principal component analysis (PCA), and molecular dynamics studies can emerge as an efficient approach to designing promising core scaffolds for coronavirus medication. The main protease [3-chymotrypsin-like protease (3CLpro)] of severe acute respiratory syndrome coronavirus (SARS-CoV)-1 and SARS-CoV-2 is one of the critical targets for designing and developing broad-spectrum antiviral therapeutic drugs. The main objective of this study was to investigate potential phytochemicals against SARS-CoV-1 and SARS-CoV-2 to ensure effective natural product-induced therapy. In this evaluation, we have selected 40 reported phytochemicals to design efficient core scaffolds that can act as potent inhibitors against the main proteases of SARS-CoV-2 and SARS-CoV-1. We categorized the selected phytochemicals into a more bioavailable and less bioavailable set, considering phytochemical drug likeliness properties. All the selected phytochemicals vigorously interacted with the catalytic dyads His41 and Cys145. Statistical analysis by MLR confirmed their contribution to structural features on binding affinities and PCA analysis for structural activity relationships for their structural pattern recognition to determine the core scaffold inhibitors. We confirmed that 4'-Hydroxyisolonchocarpin and BrussochalconeA were safe and exhibited excellent pharmacological properties. Because 4'-Hydroxyisolonchocarpin and BrussochalconeA are flavonoid derivatives, they exhibit the chalcone's ring. The presence of the reactive α,ß-unsaturated system in the chalcone's rings showed different potential pharmacokinetics with an insignificant toxicological profile. Our comprehensive computational and statistical analysis reveals that these selected phytochemicals (4'-Hydroxyisolonchocarpin, BrussochalconeA) can be used to design potential broad antiviral inhibitors against SARS-CoV-2 and SARS-CoV-1.

16.
Front Microbiol ; 14: 1191968, 2023.
Article in English | MEDLINE | ID: mdl-37415820

ABSTRACT

Introduction: Antibiotic persistence (subpopulation tolerance) occurs when a subpopulation of antibiotic sensitive cells survives prolonged exposure to a bactericidal concentration of an antibiotic, and is capable of regrowth once the antibiotic is removed. This phenomenon has been shown to contribute to prolonged treatment duration, infection recurrence, and accelerated development of genetic resistance. Currently, there are no biomarkers which would allow for segregation of these antibiotic-tolerant cells from the bulk population prior to antibiotic exposure, limiting research on this phenomenon to retrograde analyses. However, it has been previously shown that persisters often have a dysregulated intracellular redox homeostasis, warranting its investigation as a potential marker for antibiotic tolerance. Furthermore, it is currently unknown whether another antibiotic tolerant subpopulation - viable but non-culturable cells (VBNCs), are simply persisters with extreme lag phase, or are formed through separate pathways. VBNCs similarly to persisters remain viable following antibiotic exposure, however, are not capable of regrowth in standard conditions. Methods: In this article we employed an NADH:NAD+ biosensor (Peredox) to investigate NADH homeostasis of ciprofloxacin-tolerant E. coli cells on a single-cell level. [NADH:NAD+] was used as a proxy for measuring intracellular redox homeostasis and respiration rate. Results and Discussion: First, we demonstrated that ciprofloxacin exposure results in a high number of VBNCs, several orders of magnitude higher than persisters. However, we found no correlation in the frequencies of persister and VBNC subpopulations. Ciprofloxacin-tolerant cells (persisters & VBNCs) were actively undergoing respiration, although at a significantly lower rate on average when compared to the bulk population. We also noted significant heterogeneity on a single-cell level within the subpopulations, however were unable to segregate persisters from VBNCs based on these observations alone. Finally, we showed that in the highly-persistent strain of E. coli, E. coli HipQ, ciprofloxacin-tolerant cells have a significantly lower [NADH:NAD+] ratio than tolerant cells of its parental strain, providing further link between disturbed NADH homeostasis and antibiotic tolerance.

17.
Environ Pollut ; 334: 122226, 2023 Oct 01.
Article in English | MEDLINE | ID: mdl-37479173

ABSTRACT

To move towards a circular society, the recyclability potential of littered plastics should be explored to provide potential value for a product that is typically destined for landfill or incineration. This study aims to understand the changes in physical, mechanical, and chemical properties of four types of plastics (polyethylene terephthalate (PET), polypropylene (PP), polycarbonate (PC) and polylactic acid (PLA) after simulated environmental degradation. Plastic samples were subjected to different water matrices (in an attempt to simulate terrestrial, ocean, and river environments) to understand the role the environment plays on plastic degradation. Significant physical, mechanical, and chemical changes were observed for the PET, PP and PLA samples. Flakes and cracks were noted during the scanning electron microscopy (SEM) analysis of PET, PP and PLA illustrating the surface degradation that had occurred. Colour scanning of the samples provided complementary information about their suitability for upcycling or downcycling. Both PET and PP had visual colour changes, making them unsuitable for upcycling purposes. PLA had a significant decrease in its tensile strength in all environmental conditions, alongside significant chemical and surface change as revealed by Fourier-transform infrared (FTIR) and SEM analysis, respectively. PC had little to no changes in its chemical, mechanical, and physical properties due to high resistance to solar (UVA) degradation in presence of salt and natural organic matter in the form of humic acid. Therefore, out of the four types of plastics tested, PC was the only plastic determined to have good upcycling potential if collected from the environment. However, PET and PP could still be recycled into lower value products (i.e., construction materials).


Subject(s)
Plastics , Polypropylenes , Plastics/chemistry , Polyethylene Terephthalates , Waste Disposal Facilities , Recycling
18.
Water Res ; 233: 119790, 2023 Apr 15.
Article in English | MEDLINE | ID: mdl-36870107

ABSTRACT

Microplastics as vectors for contaminants in the environment is becoming a topic of public interest. Microplastics have been found to actively adsorb heavy metals, per-fluorinated alkyl substances (PFAS), polychlorinated biphenyls (PCBs), polyaromatic hydrocarbons (PAHs), pharmaceuticals and personal care products (PPCPs) and polybrominated diethers (PBDs) onto their surface. Particular interest in microplastics capacity to adsorb antibiotics needs further attention due to the potential role this interaction plays on antibiotic resistance. Antibiotic sorption experiments have been documented in the literature, but the data has not yet been critically reviewed. This review aims to comprehensively assess the factors that affect antibiotic sorption onto microplastics. It is recognised that the physico- chemical properties of the polymers, the antibiotic chemical properties, and the properties of the solution all play a crucial role in the antibiotic sorption capacity of microplastics. Weathering of microplastics was found to increase the antibiotic sorption capacity by up to 171%. An increase in solution salinity was found to decrease the sorption of antibiotics onto microplastics, in some instances by 100%. pH also has a substantial effect on sorption capacity, illustrating the significance of electrostatic interactions on the sorption of antibiotics onto microplastics. The need for a uniform experimental design when testing antibiotic sorption is highlighted to remove inconsistencies in the data currently presented. Current literature examines the link between antibiotic sorption and antibiotic resistance, however, further studies are still required to fully understand this emerging global crisis.


Subject(s)
Microplastics , Water Pollutants, Chemical , Plastics/chemistry , Anti-Bacterial Agents , Water , Adsorption , Water Pollutants, Chemical/chemistry
19.
J Pers Med ; 12(10)2022 Oct 02.
Article in English | MEDLINE | ID: mdl-36294774

ABSTRACT

The measurement of exhaled volatile organic compounds (VOCs) in exhaled breath (breathomics) represents an exciting biomarker matrix for airways disease, with early research indicating a sensitivity to airway inflammation. One of the key aspects to analytical validity for any clinical biomarker is an understanding of the short-term repeatability of measures. We collected exhaled breath samples on 5 consecutive days in 14 subjects with severe asthma who had undergone extensive clinical characterisation. Principal component analysis on VOC abundance across all breath samples revealed no variance due to the day of sampling. Samples from the same patients clustered together and there was some separation according to T2 inflammatory markers. The intra-subject and between-subject variability of each VOC was calculated across the 70 samples and identified 30.35% of VOCs to be erratic: variable between subjects but also variable in the same subject. Exclusion of these erratic VOCs from machine learning approaches revealed no apparent loss of structure to the underlying data or loss of relationship with salient clinical characteristics. Moreover, cluster evaluation by the silhouette coefficient indicates more distinct clustering. We are able to describe the short-term repeatability of breath samples in a severe asthma population and corroborate its sensitivity to airway inflammation. We also describe a novel variance-based feature selection tool that, when applied to larger clinical studies, could improve machine learning model predictions.

20.
Mutat Res Rev Mutat Res ; 789: 108415, 2022.
Article in English | MEDLINE | ID: mdl-35690418

ABSTRACT

BACKGROUND: Among children, sex-specific differences in disease prevalence, age of onset, and susceptibility have been observed in health conditions including asthma, immune response, metabolic health, some pediatric and adult cancers, and psychiatric disorders. Epigenetic modifications such as DNA methylation may play a role in the sexual differences observed in diseases and other physiological traits. METHODS: We performed a meta-analysis of the association of sex and cord blood DNA methylation at over 450,000 CpG sites in 8438 newborns from 17 cohorts participating in the Pregnancy And Childhood Epigenetics (PACE) Consortium. We also examined associations of child sex with DNA methylation in older children ages 5.5-10 years from 8 cohorts (n = 4268). RESULTS: In newborn blood, sex was associated at Bonferroni level significance with differences in DNA methylation at 46,979 autosomal CpG sites (p < 1.3 × 10-7) after adjusting for white blood cell proportions and batch. Most of those sites had lower methylation levels in males than in females. Of the differentially methylated CpG sites identified in newborn blood, 68% (31,727) met look-up level significance (p < 1.1 × 10-6) in older children and had methylation differences in the same direction. CONCLUSIONS: This is a large-scale meta-analysis examining sex differences in DNA methylation in newborns and older children. Expanding upon previous studies, we replicated previous findings and identified additional autosomal sites with sex-specific differences in DNA methylation. Differentially methylated sites were enriched in genes involved in cancer, psychiatric disorders, and cardiovascular phenotypes.


Subject(s)
DNA Methylation , Epigenome , Adolescent , Child , DNA Methylation/genetics , Epigenesis, Genetic , Epigenomics , Female , Humans , Infant, Newborn , Male , Pregnancy , Sex Characteristics
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