Search Results (14,293)

Repeated mixed-munition demolition may require explosive ordnance disposal personnel to re-enter a common demolition pit to inspect effects, recover debris and prepare subsequent stacks. Dinitrotoluene (DNT) is a recognised explosive ordnance occupational toxicant absorbed by inhalation, skin and ingestion. Urinary-tract malignancies and other adverse outcomes have been reported in highly exposed nitroaromatic-explosives workers. Recently, bladder-cancer incidence was documented as elevated among former British Army ammunition technicians. While these observations do not establish a causal relationship with DNT, they however provide a strong rationale for further investigation of credible exposure pathways. This study developed a scenario-based source-pathway-receptor model to examine whether residual DNT could constitute an occupational exposure source during these tasks. This model was applied to an explosive ordnance disposal operation involving 20 sequential demolitions and a documented aggregate TNT-equivalent basis of 1000 kg, used as a screening proxy because the operational inventory was predominantly TNT-filled. The model identified plausible primary inhalation from a blast-generated plume and secondary inhalation from resuspended residues, together with dermal and incidental-ingestion pathways. An important caveat is that it does not reconstruct individual dose or establish disease causation. Validation requires time-resolved post-blast and task-based personal air sampling, surface assessment, biomonitoring and detailed exposure reconstruction during representative demolition operations. As such, this study establishes crucial foundational hypotheses for future occupational hazard research into DNT exposure to explosive ordnance disposal personnel. Full article

Airborne fungal contamination poses an occupational health risk in environments where engineering-controls are essential for maintaining indoor air quality. However, evidence integrating assessments of engineering-control readiness and airborne fungal contamination in forensic pathology facilities remains limited, particularly in low- and middle-income countries. This study assessed engineering-control readiness, indoor environmental conditions, and airborne fungal contamination in three public forensic pathology facilities in Gauteng Province, South Africa, and explored factors associated with airborne fungal contamination. A cross-sectional occupational hygiene study was conducted in three public forensic pathology facilities. Engineering-control readiness was assessed using structured walkthroughs and summarised using a study-specific Engineering Control Readiness Index (ECRI). Indoor temperature, relative humidity, carbon dioxide (CO₂), and airborne fungal concentrations were measured concurrently. Duplicate fungal air samples were collected at predefined locations over three consecutive sampling days. For the primary regression analysis, duplicate fungal measurements were averaged within each physical sampling location and sampling day, yielding 54 indoor location-day observations from 18 physical indoor sampling locations. Multivariable log-linear regression included facility, functional work area, area-specific ventilation and environmental-control deficiency, temperature, relative humidity and CO₂, with cluster-robust inference accounting for repeated measurements within physical sampling locations. Overall ECRI scores ranged from 50.1% to 53.9%, with ventilation and environmental control representing the weakest domain. Airborne fungal concentrations differed significantly between facilities, with FPF G recording the highest indoor median concentration (740 CFU/m³). Cladosporium spp. and Penicillium spp. predominated. After adjustment for facility, functional work area and environmental conditions and accounting for repeated sampling, engineering-control deficiency was not independently associated with fungal concentration (adjusted change per 10-percentage-point increase: −16.3%; 95% CI: −70.9% to 140.9%; p = 0.727). Substantial engineering-control deficiencies and airborne fungal contamination were identified; however, the independent contribution of engineering-control deficiency could not be estimated with adequate precision in this three-facility study. Larger longitudinal studies incorporating objective ventilation-performance measurements are required to clarify the contribution of specific engineering controls to occupational bioaerosol exposure. Full article

Black soldier fly larvae (BSFL; Hermetia illucens) oil and flaxseed oil provide contrasting fatty acid profiles and may serve as alternative lipid feed materials in ruminant nutrition. This study assessed low-α-linolenic/high-linoleic flaxseed oil, BSFL oil, and their blends using an in vitro rumen fermentation screening with pooled bovine rumen inoculum and a randomized prepartum feeding trial in 32 twin- or triplet-bearing Olkuska ewes. In vitro, the single oils and a 1:1 blend were evaluated at two inclusion levels; total VFA concentration was unchanged, whereas propionate proportion, the acetate-to-propionate ratio, methane, ammonia, and incubation-fluid fatty acid profiles showed treatment-dependent responses. In vivo, an unsupplemented control was compared with flaxseed oil, BSFL oil, and a 2:1 blend supplied at 30 g/day for 21 days before expected parturition. Colostrum fat concentration differed among treatments (p = 0.036); the 2:1 blend group had a higher value than the control group (11.29% vs. 8.26%; Dunnett-adjusted p < 0.05), while major fatty acid classes did not differ. Supplementation was also associated with differences in selected minor colostrum fatty acids and several serum metabolic variables. Colostrum yield was not measured; therefore, this finding reflects fat concentration rather than total colostrum fat output. Serum total antioxidant status (TAS) was unaffected, while a treatment-by-time interaction was observed for γ-glutamyl transferase. The tested plant- and insect-derived oils therefore modified ruminal lipid transformations and selected maternal and colostrum traits without a detectable change in TAS. Full article

Background: Toxoplasma gondii infection during pregnancy may lead to congenital toxoplasmosis and serious pregnancy complications. In Kenya, however, toxoplasmosis is not screened during routine antenatal care, and there is limited local data on maternal seroprevalence and associated risk factors. This study determined the seroprevalence of T. gondii infections. It examined its association with socio-demographic, obstetric characteristics, awareness levels, and exposure behaviours among pregnant women visiting the antenatal clinic at Pumwani Maternity Hospital in Nairobi, Kenya. Methods: A cross-sectional study was conducted among 298 pregnant women consecutively recruited at Pumwani Maternity Hospital in Nairobi County between July and October 2025. Data on socio-demographics, obstetric characteristics, knowledge, and exposure practices were collected using a structured questionnaire. Blood specimens were obtained from consenting prenatal patients, and anti-T. gondii IgG antibodies were detected by indirect enzyme-linked immunosorbent assay (ELISA). Associations between seropositivity and risk factors were assessed using univariable logistic regression, followed by two separate multivariable models. Variables with p < 0.25 were considered for multivariable analysis, followed by backward likelihood-ratio elimination. Model calibration was assessed using the Hosmer–Lemeshow test. Results: The overall seroprevalence of anti-T. gondii IgG was 24.5% (73 of 298). In the sociodemographic model, women who were self-employed (adjusted odds ratio [AOR] = 0.26, 95% CI: 0.13–0.53) and formally employed (AOR = 0.25, 95% CI: 0.11–0.59) had lower odds of seropositivity than unemployed women. Women aged 25–33 years had higher odds than those aged 18–24 years (AOR = 2.45, 95% CI: 1.06–5.62). Having two children was associated with lower odds than a first birth (AOR = 0.40, 95% CI: 0.18–0.90), while parity of four or more showed a borderline increase in odds (AOR = 3.11, 95% CI: 0.99–9.76). In the knowledge/exposure model, good awareness of population risk groups was linked to higher odds of seropositivity (AOR = 3.34, 95% CI: 1.21–9.24), but exposure-practice variables were not independently associated. Stratified analyses showed significant demographic differences in exposure practices, such as eating undercooked meat in the third trimester of pregnancy (p = 0.021) and unwashed vegetable consumption by pregnant women from Kamkunji Sub-County (p = 0.005). Parity of three increased infection risk (p = 0.007). Conclusions: About 25% of participants showed evidence of prior T. gondii exposure. Seropositivity correlated with specific sociodemographic and obstetric factors as well as awareness of groups at risk. These results endorse targeted antenatal education that emphasises practical food safety and environmental hygiene, aligned with a One Health approach. Further longitudinal and multicenter research, including IgM and IgG avidity testing, is needed to differentiate recent from past infections and to better understand risks associated with congenital toxoplasmosis. Full article

The type VI secretion system (T6SS) is a contact-dependent bacterial weapon to inject hazardous proteins into competitors and can be pivotal for bacterial fitness. Throughout the lifecycle of Vibrio cholerae, beneficial and detrimental activities of the T6SS have been described, but its role in biofilm-associated interactions remains poorly understood. Here, we show that biofilm formation is accompanied by significant repression of T6SS genes. Expression analyses across multiple V. cholerae isolates revealed consistent downregulation of the major T6SS gene cluster in biofilm-derived cells relative to planktonic cultures. Consistent with this biofilm-dependent repression, a loss of the T6SS did not affect V. cholerae biofilm formation. Notably, biofilm-derived V. cholerae wild-type isolates and their isogenic T6SS-deletion mutants displayed comparable resistance to attacks by T6SS-reactive Pseudomonas aeruginosa. These findings suggest that T6SS repression during biofilm growth provides a fitness advantage for V. cholerae by limiting susceptibility to T6SS-mediated counterattacks from neighboring heterologous T6SS⁺ predatory species. Our results, therefore, identify conditional T6SS silencing as a potential adaptive strategy that promotes survival within multispecies microbial communities, particularly in environments containing bacteria with highly active or more potent T6SS machineries. Full article

Oral lichen planus (OLP) is a chronic, immune-mediated inflammatory disorder of the oral mucosa recognized as an oral potentially malignant disorder, with a pooled malignant transformation rate of approximately 1–1.4% that is highest in atrophic-erosive and tongue lesions. Its most feared outcome, oral squamous cell carcinoma (OSCC), remains associated with a 5-year survival below 50% and a substantial clinical, functional, and economic burden. Because conventional management, like topical corticosteroids for OLP and surgery with or without radiotherapy for OSCC, entails cumulative toxicity and limited long-term efficacy, non-pharmacological strategies are attracting growing interest. This narrative review critically appraises the available evidence across the OLP-to-OSCC continuum, examining high-power ablative lasers, low-level laser therapy/photobiomodulation, photodynamic therapy, nutraceutical and phytotherapeutic agents (including melatonin, curcumin, aloe vera, coconut, zinc, and vitamin D), cryotherapy, ozone therapy, probiotics, and psychological interventions, alongside supportive measures in OSCC such as oral hygiene management, photobiomodulation for treatment-related toxicity, and post-treatment rehabilitation. Evidence is strongest and most consistent for photobiomodulation in OLP, whereas most other modalities remain promising but limited by small samples, heterogeneous protocols, and scarce placebo-controlled data. A multidisciplinary, evidence-graded approach is essential to optimize early detection, disease control, and quality of life. Full article

Objectives: The term “never treated” refers to individuals who self-report having never ingested tablets during any round of Mass Drug Administration (MDA) against Lymphatic Filariasis (LF). This study estimated the pooled prevalence of never-treated individuals with MDA for LF and identified factors associated with persistent non-treatment. Methods: This systematic review and meta-analysis was registered in PROSPERO [CRD420251270067] and conducted in accordance with the PRISMA 2020 guidelines. Relevant literature was identified by searching databases, i.e., PubMed, Scopus, Cochrane Central, Embase, Web of Science, and Epistemonikos from January 2000 to December 2025, and only studies published in English were included. The AXIS tool was used to assess the study quality. A random-effects model with 95% CI was applied to estimate the pooled prevalence. Subgroup, leave-one-out sensitivity, and meta-regression analyses were conducted to explore the heterogeneity. Results: Eighteen studies including 24,940 individuals showed the pooled prevalence of never treatment during all MDA rounds at 26% (95% CI: 16% to 37%, I² = 99.7%, 95% prediction interval: 0% to 75%). Exploratory subgroup analysis indicated wide regional and MDA round-specific variations. Meta-regression indicated that publication year did not explain the variability. Common reasons for persistent non-treatment included fear of side effects, limited knowledge, difficulty swallowing the pills, and absence during drug distribution. Conclusions: Persistently never-treated populations may represent an important programmatic barrier to LF elimination. Given the very low certainty of evidence, extreme heterogeneity, and potential publication bias, these estimates should be interpreted cautiously. Future research should ensure broader geographical representation, including both urban and rural areas, and explore structural, behavioural, and socio-cultural determinants to better target high-risk groups. Full article

Background: The longevity of composite restorations in primary teeth depends on the preservation of both mechanical performance and surface integrity under daily oral hygiene procedures. While powered toothbrushes have been widely investigated for plaque control, their potential effects on restorative materials in the primary dentition remain insufficiently characterized. This preliminary in vitro study evaluated the influence of manual, oscillating-rotating electric, and sonic toothbrushing on the surface microhardness, surface roughness, and shear resistance of resin composite restorations in primary teeth. Methods: Thirty extracted non-carious primary teeth were standardized, cavity-prepared, and restored using a self-etch adhesive system and a resin composite material. Specimens were randomly assigned to three groups (n = 10) according to brushing modality: manual, electric, or sonic. After a standardized 60 min brushing simulation under controlled conditions, surface microhardness was measured using a Vickers microhardness tester, surface roughness was assessed with contact profilometry, and restoration retention was evaluated as maximum load at failure under shear-type mechanical loading. Surface morphology was further analyzed by scanning electron microscopy. Results: No statistically significant differences were observed among groups in surface microhardness (p = 0.606) or maximum dislodgement load (p = 0.806). In contrast, surface roughness differed significantly according to toothbrush type (p < 0.001), with the highest Ra values recorded in the sonic group. Scanning electron microscopy corroborated these findings, showing progressively greater surface irregularities, porosities, and microdefects from manual to sonic brushing. Under the present in vitro conditions, the sonic toothbrush group showed the highest final surface roughness values, whereas no significant differences were observed in microhardness or restoration retention. Conclusions: Under the present short-term in vitro conditions, the sonic toothbrush group showed higher final surface roughness values than the manual and electric groups, while no significant differences were observed in microhardness or restoration retention. These results are limited to the specific toothbrush systems tested and these findings should be interpreted as preliminary in vitro results from an exploratory sample with limited statistical power. Full article

Antimicrobial resistance (AMR) presents a global health challenge that is projected to cause nearly 2 million deaths annually by 2050. With a growing ageing population and the rise of antibiotic-resistant strains globally, developing effective alternatives to combat infections while reducing AMR risks is critical. Over recent decades, antibiotic-free strategies have emerged as promising approaches, offering advantages over traditional antibiotics and reducing the likelihood of resistance. This review highlights antibiotic-free antimicrobial strategies for applications in chronic wound care, hard tissue repair, personal protective equipment, as well as hospital hygiene and infection control. We begin by outlining the broader AMR problem and then examine natural strategies—including the use of agents such as manuka honey—followed by synthetic approaches involving nanomaterials and metal–organic frameworks (MOFs), as well as biological and bioinspired antimicrobial strategies, involving antimicrobial peptides, antibodies, bacteriophages, extracellular vesicles, and macrocycles. Finally, we discuss innovations in artificial intelligence (AI)-assisted antimicrobial development and stimulus-responsive materials, before introducing a conceptual design framework for antibiotic-free antimicrobial materials. This review provides a comprehensive assessment of emerging antibiotic-free strategies to guide the development of next-generation antimicrobial solutions that reduce reliance on antibiotics and mitigate AMR in clinical and healthcare settings. Full article

Mycotoxins are secondary fungal metabolites that have continuously attracted research interest, both for their potential negative effects on animal and human health and for the economic losses they entail. Studies assessing exposure to mycotoxins have become increasingly widespread. The aim of this study was to provide a comprehensive description of mycotoxins and to evaluate the evolution of research on monitoring mycotoxin exposure using human urine samples, concerning analytical techniques and occurrence. Studies published in English over the last 25 years from four databases (Web of Science, PubMed, Science Direct, Scopus) were analyzed. Evaluating 73 original articles, a constant interest in the analysis of ochratoxin A in human urine samples could be observed (maximum level 148 ng/mL), a fact also justified by its demonstrated toxicity. The most commonly used analytical technique to evaluate mycotoxin presence in human urine was liquid chromatography coupled with high-performance detectors. The limitations of the review include the large period covered and the lack of mycotoxin concentrations expressed in ng biomarker/mL urine in some articles. Finally, an overview of how mycotoxin levels in human urine can be applied to mycotoxin exposure risk assessment was included. Full article

Background/Objectives: Poor oral health, which is often overlooked in nursing homes (NHs), is associated with aspiration pneumonia. This analysis assesses the cost effectiveness of an oral hygiene intervention, “Mouth Care Without a Battle©” (MCWB), which trains NH staff to provide daily mouth care. The first year of a pragmatic cluster randomized effectiveness trial conducted in 14 NHs demonstrated a significant reduction in pneumonia incidence in intervention NHs. Methods: Because the two-year primary outcome was not statistically significant, the first-year analysis is post hoc. The incremental cost-effectiveness ratio (ICER) of costs (staff training, time spent providing mouth care, and pneumonia-related hospitalizations) to effects (reductions in pneumonia cases) over one year was estimated using bootstrapping. Results: Analyses for 1605 residents with clustering by NH show that the likelihood that MCWB is cost-saving ranges from 6.5% to 61.1% depending on whether staff are paid benefits and various levels of estimated hospital costs. Similarly, the likelihood that MCWB results in reduced pneumonia cases but with higher costs ranges from 32.0% to 86.6%. Whether MCWB is cost-effective depends on society’s willingness to pay for reduced pneumonia cases and related unmeasured benefits. These estimates may represent a lower bound of potential cost savings because analyses did not include costs of treating pneumonia if not hospitalized, ambulance transport, or the emotional costs of illness. However, other excluded costs (e.g., dental restorations) and resources required to improve fidelity could reduce the likelihood of cost savings. Conclusions: MCWB and similar interventions that improve oral health care in NHs may yield cost savings or produce benefits from the reduction in pneumonia that justify net increases in costs incurred. It is also important to consider who bears the costs (e.g., the NH) versus who reaps the benefits (e.g., healthier residents and reduced Medicare payments). Full article

Eusocial insects maintain their colonies through diverse cooperative tasks, yet patterns among these behaviors remain poorly understood in hornets. To examine temporal polyethism, we observed a Vespa velutina nigrithorax colony under controlled laboratory conditions (26 °C, 60% RH). Workers were categorized into 5-day cohorts and monitored across five tasks: nest hygiene, prey foraging and first pellet handling, second pellet handling, brood feeding, and foraging for nest materials. Adult emergence occurred in three synchronized cohorts. Workers began to transition to tasks outside of the nest after 6.3 ± 0.9 days. Younger workers performed hygiene and second pellet processing, mid-aged hornets specialized in prey foraging and first pellet formation, while older workers increasingly foraged for nest materials. Brood feeding was observed by hornets of all ages. Cooperative second pellet processing reduced handling duration by workers compared with first pellets. Of the five potential nest materials deliberately provided, adults most frequently collected hornet nest envelopes and tree bark. Multiple correspondence analysis and clustering confirmed distinct but overlapping task profiles, indicating flexibility instead of a fixed sequence. These findings quantitatively demonstrate age-related division of labor in V. velutina similar to that of other social wasps, highlighting behavioral flexibility and cooperative strategies that likely enhance colony efficiency. Full article

Sustainable Development Goal 6 (SDG 6) seeks to ensure the availability and sustainable management of clean water and sanitation for all by 2030. Despite notable policy and institutional reforms, many developing countries, including South Africa, continue to face complex and interconnected challenges related to water quality, governance, infrastructure, financing, and institutional capacity that impede progress towards achieving SDG 6. A systematic literature review methodology was applied using predefined eligibility criteria and data sources to identify evidence related to drinking water quality and SDG 6 implementation. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) approach, 241 records were initially identified. After screening and eligibility assessment, 115 records were retained for detailed analysis, while studies not focused on South Africa, not directly related to drinking water quality, or lacking sufficient empirical evidence were excluded. The review reveals that drinking water quality in South Africa is increasingly threatened by various challenges that may hinder the achievement of SDG 6. The findings highlight the importance of integrated interventions that combine infrastructure renewal, technological innovation, strengthened regulatory compliance, improved wastewater management, ecosystem protection, institutional reform, and stakeholder participation. To address these interconnected challenges, the study proposes the Governance, Technology, Finance, Capacity and Institutions (GTFCI) Framework as an integrated implementation pathway for SDG 6. The framework positions governance, institutional capacity, technology, and financing as foundational enablers of water service delivery, while integrated water resources management (IWRM) serves as the coordinating mechanism linking water services, ecosystem sustainability, and long-term water security. International cooperation and community participation function as cross-cutting support mechanisms that reinforce implementation across all SDG 6 targets. The proposed GTFCI Framework provides a practical and strategic model for strengthening drinking water quality, enhancing water security, and accelerating progress towards the sustainable achievement of SDG 6 by 2030. Full article

Background/Objectives: Evidence from repeated-measures studies examining denture use, subjective chewing difficulty, and depressive symptoms remains limited. This study examined the population-averaged associations of denture use and subjective chewing difficulty with depressive symptoms across nine waves of the Korean Longitudinal Study of Aging (KLoSA). Methods: Data from 10,137 participants contributing 68,937 person-wave observations across nine KLoSA waves (2006–2022) were analyzed. Depressive symptoms were assessed using the 10-item Center for Epidemiologic Studies Depression Scale (CESD-10). Generalized estimating equations (GEEs) were used to account for repeated observations within participants. Sex-stratified analyses and formal interaction tests were additionally performed. Results: In adjusted sex-stratified analyses, denture use was associated with a higher expected mean CESD-10 score among women [exp(B) = 1.068, 95% CI: 1.044–1.092] but not among men. Greater subjective chewing difficulty was consistently associated with higher expected mean CESD-10 scores among both men and women and among both denture users and non-denture users. The sex × denture use interaction was significant [exp(B) = 1.064, 95% CI: 1.043–1.085, p < 0.001], and sex × subjective chewing difficulty interactions were also significant among both denture users and non-denture users (all p ≤ 0.001). Conclusions: Greater subjective chewing difficulty was consistently associated with higher depressive symptom levels across repeated observations among both denture users and non-denture users. Sex modified the associations of denture use and subjective chewing difficulty with depressive symptoms. Perceived chewing function may provide additional information beyond denture status when assessing oral health-related vulnerability associated with depressive symptoms; however, temporal direction and causality cannot be inferred from these analyses. Full article

Objectives: The SARS-CoV-2 pandemic caused major morbidity, mortality, and economic disruption, highlighting the need to better understand zoonotic spillover risks posed by coronaviruses. We investigated whether archived human sera from forested Guinea contained evidence of prior exposure to coronaviruses antigenically related to known pathogenic human coronaviruses. Methods: Archived sera collected in 2017–2018 from wildlife hunter communities in Guinea were analysed using serological assays against spike glycoproteins from SARS-CoV, SARS-CoV-2, MERS-CoV, and seasonal human coronaviruses. Binding responses to receptor binding domains were also assessed, together with spatial and subgroup analyses. Results: Pre-pandemic sera showed IgG cross-reactivity to SARS-CoV, SARS-CoV-2, and MERS-CoV spike antigens. A distinct subgroup demonstrated strong binding to both SARS-CoV and MERS-CoV receptor binding domains. Conclusions: These findings highlight the utility of sero-epidemiology in identifying potential zoonotic spillover. However, further investigation is needed to identify these viruses and determine their homology to known pathogenic coronaviruses. Full article