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Effectiveness of Platelet Rich Plasma in Reducing Oronasal Fistula and Scar Width in Primary Cleft Lip and Palate Repair-A Systematic Review and Meta-Analysis.

This review aimed to investigate platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) efficiency in reducing oronasal fistula during primary cleft lip and palate repair. An extensive search of PubMed, Google Scholar, Global Index Medics (WHO), PubMed Scopus, Cochrane Central, Proquest was performed up to march 2025. Eligible studies included prospective RCTs and non-randomized controlled trials in human subjects. Patients aged 6-24 months undergoing primary cleft lip and palate repair were involved. Interventions involved intraoperative use of PRP/PRF compared with controls without PRP/PRF. The primary outcome was occurrence of oronasal fistula; secondary outcomes were scar width, wound infection and postoperative bleeding with wound dehiscence. Study selection followed PRISMA guidelines, and the risk of bias was determined with the ROB-2 and ROBINS-I method of assessment. Seven studies met the required criterion and were qualitatively synthesized. Evidence suggested that PRP/PRF application was associated with a lower incidence of oronasal fistula and reduced scar width compared with controls. Additional benefits included accelerated wound healing and faster recovery. The use of autologous PRP was also reported to decrease the need for further surgical interventions. However, the certainty of evidence was limited due to small sample sizes and methodological heterogeneity. PRP and PRF show promising benefits in cleft lip and palate repair, particularly decreased fistula formation and reduced scar width. Nevertheless, current evidence is of low to very low certainty. Larger, well-designed randomized trials are required to validate the results obtained. Trial Registration: PROSPERO registration no. CRD420251032421.

Humans

Fractional laser therapy versus microneedling for non-acne scars and scar-like dermal fibrotic lesions.

BACKGROUND: Scarring caused by trauma, burns, surgery, and other dermal fibrotic conditions can lead to functional limitation and cosmetic distress. The comparative effectiveness of fractional laser therapy and microneedling for non-acne scars remains uncertain. METHODS: We conducted a systematic review and meta-analysis of randomized controlled trials comparing fractional laser therapy with microneedling for non-acne scars and scar-like dermal fibrotic lesions. Following a PROSPERO-registered protocol and PRISMA guidelines, we searched PubMed, EMBASE, Web of Science, Cochrane Library, and CNKI from inception to May 2026 without language restrictions. Parallel-group and split-body randomized trials were eligible. Random-effects models were used to calculate standardized mean differences (SMDs) for continuous outcomes and odds ratios (ORs) for dichotomous outcomes. RESULTS: Nine randomized controlled trials were included. Fractional laser therapy showed a statistically significant advantage over microneedling in scar scores (SMD = -0.99, 95% CI [-1.83, -0.15], P = 0.02) and collagen fiber regeneration (SMD = -2.14, 95% CI [-3.57, -0.72], P = 0.03). No statistically significant differences were found between the two interventions for elastic fiber improvement, epidermal thickness, or adverse events. Subgroup analyses did not show clear or consistent significant differences according to laser type, including comparisons between traditional and non-traditional fractional lasers and between CO₂ and non-CO₂ fractional laser systems. Substantial heterogeneity was observed across several outcomes, indicating considerable between-study variability. CONCLUSION: Based on currently available randomized evidence, fractional laser therapy may provide superior improvement in overall scar severity and collagen fiber regeneration compared with microneedling for non-acne scars and scar-like dermal fibrotic lesions. However, no clear differences were observed for elastic fiber improvement, epidermal thickness, or adverse-event incidence. Given the substantial heterogeneity, limited sample sizes, and possible reporting bias, these findings should be interpreted cautiously. Further large, standardized trials with longer follow-up are needed.

Humans

Comparison of a 755-nm picosecond laser and a 1565-nm nonablative fractional laser for the treatment of atrophic acne scars: a 20-week prospective, randomized, split-face clinical study.

To compare the efficacy and safety of a 755-nm picosecond laser with a diffractive lens array (P-DLA) and a 1565-nm nonablative fractional laser (NAFL) for the treatment of atrophic acne scars. Twenty-seven patients with atrophic acne scars underwent three sessions of randomized split-face treatment with P-DLA and NAFL at 4-week intervals. Patients were followed up at 1, 2, and 3 months after the final treatment. Efficacy was assessed using the &#xc9;chelle d'&#xc9;valuation Clinique des Cicatrices d'Acn&#xe9; (ECCA) grading scale, the Investigator's Global Assessment (IGA) score, patients' self-rated improvement, and overall satisfaction. Treatment-related adverse reactions were recorded daily by patients until resolution. Both modalities demonstrated significant improvements in scar appearance based on ECCA score, IGA score, and patients' self-rated improvement (P&#x2009;<&#x2009;0.001). No statistically significant differences in efficacy were observed between the two treatments. However, the P-DLA group showed higher patient satisfaction (P&#x2009;=&#x2009;0.035) and a more favorable safety profile, including shorter durations of erythema and edema and the absence of crusting. Both P-DLA and NAFL were effective and safe for the treatment of atrophic acne scars, with similar efficacy. P-DLA offered better tolerability.

Humans

Non-genetic Risk Factors for Allopurinol-Induced Severe Cutaneous Adverse Reaction (SCAR): A Systematic Review.

BACKGROUND: Allopurinol-induced severe cutaneous adverse reactions (SCARs) are rare but potentially life threatening, particularly in Asian populations. While the genetic marker HLA-B*58:01 is a well-established risk factor, non-genetic factors may also contribute. This systematic review synthesizes evidence on associations between non-genetic risk factors and allopurinol-induced SCAR. METHODS: We searched MEDLINE, Scopus, Cochrane Library and Web of Science from inception to 29 June 2026 for observational studies examining non-genetic risk factors for SCAR, defined as Stevens-Johnson Syndrome, Toxic Epidermal Necrolysis, Acute Generalised Exanthematous Pustulosis, or Hypersensitivity Syndrome/Drug Reaction with Eosinophilia and Systemic Symptoms. Adults aged &#x2265;&#xa0;18 years were included. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using a random-effects model; heterogeneity was assessed with I2. Mean differences were calculated for continuous variables. NIH Study Quality Assessment Tool was used for quality assessment of the studies. RESULTS: Twenty-six studies were included. Female sex (20 studies; 3340 SCAR cases, 562,647 controls) was associated with an increased risk of allopurinol-induced SCAR (OR 2.06; 95% confidence interval (CI) 1.25-3.38). Chronic kidney disease (16 studies; 1625 SCAR cases, 553,804 controls) was also significantly associated with SCAR (OR 3.78; 95% CI 1.99-7.17). Five studies (177 SCAR cases, 1368 controls) reported higher allopurinol doses among SCAR cases than tolerant controls (mean difference 19.61 mg; 95% CI 2.97-36.24). No significant associations were observed for age or concomitant diuretic use in the primary meta-analyses. Substantial heterogeneity was observed across studies. Sensitivity analyses demonstrated consistent findings for most factors, although concomitant diuretic use became significantly associated with SCAR after exclusion of non-Asian and zero-event studies. CONCLUSION: CKD, female sex, and higher allopurinol dose were identified as significant non-genetic risk factors for allopurinol-induced SCAR. These findings support consideration of non-genetic factors alongside pharmacogenomic screening in future risk-stratification strategies. However, substantial heterogeneity and potential publication bias limit the certainty of the available evidence. Well-designed studies evaluating non-genetic predictors as primary outcomes are needed to develop robust integrated risk prediction models for clinical decision making.

Journal Article

Efficacy of an Adhesive Hydrocolloid Bandage on Wound Healing: Findings of a 28-Day, Single-Centre, Randomised, Controlled Study.

This single-centre, randomised, controlled study assessed the wound healing efficacy of adhesive bandages in eligible healthy adults (N&#x2009;=&#x2009;36) aged 25-55 with Fitzpatrick skin types II and III using a model of laser-induced wounds. Here, we report data for wounds that were randomised to treatment with either a hydrocolloid bandage for multi-day use (BAND-AID Adhesive Bandage Hydroseal), standard of care (SoC) (BAND-AID Adhesive Bandage Tru-Stay Sheer) or an uncovered control. Primary endpoints included the time to complete healing and a composite wound healing score. Hydrocolloid bandage-treated wounds healed twice as fast as the uncovered control or SoC-treated wounds. Median time (days) to complete healing was significantly faster for the hydrocolloid bandage-treated wounds (6.9) versus SoC (11.9) and uncovered control (11.8). Hydrocolloid bandage-treated wounds had significantly better composite wound healing scores versus SoC and versus uncovered control over 2&#x2009;weeks. At Day 28, cosmesis was better with hydrocolloid bandage treatment (0.3) versus SoC (0.6) and uncovered control (2.1) (change from baseline in a composite scar score; higher score&#x2009;=&#x2009;worse outcome). Multi-day wound occlusion with a hydrocolloid bandage promoted faster healing and improved cosmesis compared with daily SoC dressings or uncovered control.

Humans

A standardised risk-stratified approach to the urological management of children with spina bifida.

BACKGROUND: The establishment of a multidisciplinary spina bifida (SB) clinic in 2006 resulted in a review of the literature and an audit of renal outcomes based on then management practices. The audit showed 17% new onset renal scarring over a mean 5.8-year follow-up period. This prompted the development of a local protocol based on risk stratification combining serial ultrasound and non-invasive bladder function assessments, with invasive urodynamic studies reserved for high-risk patients. OBJECTIVE: This study sought to assess the impact of a risk stratified protocol on renal scarring and continence outcomes in children with SB. METHODS: A single centre, retrospective case review of SB patients treated after the introduction of the protocol was conducted. Electronic medical records were used to access patient demographics, continence status and the results of investigations and adherence to the local management protocol. Management that deviated from the protocol was deemed non-adherence. Renal scarring was determined by the presence of scarring on DMSA renogram. Continence was defined as having no urinary incontinence or no more than a single episode of incontinence in a month in patients above the age of 5. For statistical analysis, descriptive statistics in percentages were used, for comparisons of dichotomous variables the Students t-test was performed and to calculate statistical significance a Fisher exact test was done. RESULTS: 167 SB patients were identified with a mean follow up of 56 months. 141 patients were considered adherent to the protocol, 26 were non-adherent. In the protocol adherent group 5 patients (3.5%) developed renal scarring compared with 6 patients (23%) managed out of protocol (p = 0.002). Overall, 49/108 patients were continent either self-voiding 8/108 (7%), with urethral CIC 19/108 (20%) and 22/108 (45%) of them required bladder augmentation. Urinary continence improved with age with 26% continence at age 10, 64% continence by age 15 and 90% continent above 15 years of age. CONCLUSION: A management approach based on risk stratification resulted in incidence of renal scarring that is better than historical controls and comparable to published outcomes. Social continence was achieved in 90% of SB patients by 15 years of age. Hostile bladder changes can be readily identified using non-invasive assessment methods. An expectant treatment approach based on risk stratification is associated with good long term renal outcome and utilises invasive urodynamic resources for SB patients at high risk of renal injury or to address urinary continence in the older child.

Humans

Hydrodissection-assisted laparoscopic orchiopexy utilizing needle grasper for palpable undescended testes: Clinical efficacy analysis.

OBJECTIVE: Laparoscopic orchiopexy has emerged as a viable alternative for the treatment of palpable undescended testis (UDT). This study aims to evaluate the feasibility and efficacy of needle-grasper hydrodissection-assisted laparoscopic orchiopexy (NHLO) in comparison to conventional laparoscopic orchiopexy (CLO) for palpable UDT. METHODS: A cohort of 96 patients diagnosed with palpable UDT, admitted between January 2020 and April 2024, was included in this study. Among these, 54 patients underwent NHLO, while 42 patients were treated with CLO. In the NHLO procedure, normal saline was injected into the retroperitoneal space to create a hydrodissection barrier, facilitating the separation and protection of the vas deferens and spermatic cord. The vas deferens and spermatic cord were meticulously dissected following the principles of integrity and minimal tissue trauma. Outcome measures included final testicular position, testicular volume growth, testicular atrophy, success rate, and postoperative complications. RESULTS: No significant differences were observed between the NHLO and CLO groups in terms of age, laterality, operative time (NHLO: 38-46 min; CLO: 39-48 min), or complication rates (NHLO: 1.9 %; CLO: 0.0 %). At follow-up, all patients in both groups exhibited palpable testes in satisfactory scrotal positions. Notably, no visible abdominal scarring was observed in the NHLO group, whereas there were two noticeable scars on the abdomen in CLO. CONCLUSION: Needle-grasper hydrodissection-assisted laparoscopic orchiopexy is a safe, effective, and minimally invasive technique that provides optimal protection of the vas deferens and spermatic cord while achieving excellent cosmetic outcomes.

Humans

Endoscopic submucosal dissection for locally recurrent gastric neoplasia following endoscopic resection: a systematic review and meta-analysis.

BACKGROUND AND AIMS: Endoscopic submucosal dissection (ESD) for locally recurrent gastric neoplasia following endoscopic resection (ER) is technically challenging because of scar-related submucosal fibrosis. We performed a systematic review and meta-analysis to evaluate the efficacy and safety of salvage ESD in this setting. METHODS: Multiple databases were searched through December 2025 for studies reporting ESD outcomes for locally recurrent gastric lesions at or contiguous with a prior ER scar. Primary outcome was curative resection and need for surgery. Secondary outcomes were en bloc and R0 resection, local recurrence, delayed bleeding, and perforation. Meta-analyses were performed using a random effects model. Heterogeneity was assessed using I2. RESULTS: Seven studies (259 patients; 265 ESDs) were included. Across 5 studies and 243 ESDs, pooled curative resection rate was 69.7% (95% CI, 60.6-78.1; I2 = 38%), while 8.2% (95% CI, 3.3-14.6; I2 = 38.4%) required surgery. En bloc resection rate was 92.3% (95% CI, 79.1-99.7; I2 = 83.7%) across 6 studies, and pooled R0 resection rate was 87.5% (95% CI, 82.1-92.2; I2 = 0%) across 4 studies. Over a mean follow-up of 42 months, pooled local recurrence was 2.0% (95% CI, 0.0-9.7; I2 = 54.1%) across 6 studies. Delayed bleeding was 4.1% (95% CI, 0.8-9.0; I2 = 40.8%) and perforation was 4.1% (95% CI, 1.6-7.3; I2 = 0%). CONCLUSIONS: ESD for locally recurrent gastric neoplasia after ER achieves acceptable curative resection, high en bloc/R0 resection, and low local recurrence and morbidity. It is a viable organ-preserving option for appropriately selected patients, ideally performed at expert centers with close surveillance.

Humans

Artificial intelligence-derived myocardial fibrosis on cardiac magnetic resonance for prognosis in cardiomyopathy: A systematic review of a sparse evidence base.

BACKGROUND: Myocardial fibrosis on cardiovascular magnetic resonance (CMR), assessed by late gadolinium enhancement (LGE) and parametric mapping, is an established predictor of adverse events in cardiomyopathy. We assessed whether artificial intelligence (AI) quantification of fibrosis adds independent prognostic value. METHODS: We searched six databases, a clinical-trials register, and a preprint server from inception to 13 June 2026. Eligible studies used AI to generate a fibrosis marker in adults with ischemic or nonischemic cardiomyopathy, with covariate-adjusted outcomes over &#x2265;12 months. Risk of bias was assessed using PROBAST, PROBAST+AI, and QUIPS. Fewer than three comparable studies precluded meta-analysis; certainty was rated using GRADE. RESULTS: Of 448 records (381 after de-duplication), 18 full texts were reviewed and two included, one peer-reviewed and one preprint. In an ischemic-cardiomyopathy registry (Ghanbari et al.; n = 216 analytic, 26 events), AI-derived dense LGE scar predicted arrhythmic events (univariable hazard ratio [HR] 2.35, 95% CI 1.33-4.15), and AI-derived but not manual scar improved discrimination beyond guideline criteria (area under the curve 0.63 to 0.68; p = 0.02). In a nonischemic dilated-cardiomyopathy preprint (Kim et al.; n = 347, 119 events), automated extracellular volume &#x2265;30% predicted cardiovascular death or heart-failure hospitalization (adjusted HR 2.00, 95% CI 1.32-3.03). Both were at high risk of bias, with data-derived thresholds and no external validation. CONCLUSIONS: Across only two studies, AI-derived fibrosis was independently associated with adverse cardiovascular events, but its added value over manual quantification remains unproven. Certainty was very low. The evidence base is sparse and not yet ready for clinical use.

Humans

Alternative End Joining Dependency Imposed by miR-21-5p Defines Radiation Resistance and a Targetable Vulnerability in Oral Squamous Cell Carcinoma.

PURPOSE: Clinical control of oral squamous cell carcinoma (OSCC) is constrained by heterogeneous radiosensitivity driven by divergent DNA damage response programs. The architecture and functional contribution of alternative end joining (Alt-EJ), an error-prone DNA double-strand break (DSB) repair pathway frequently upregulated in cancer, to radiation resistance remains poorly defined. METHODS AND MATERIALS: We profiled microRNAs in radioresistant OSCC clones and performed multiomic integration across an institutional OSCC cohort, an external OSCC cohort from the Gene Expression Omnibus, The Cancer Genome Atlas pan-cancer tumors, and cell lines characterized by Sanger Genomics of Drug Sensitivity in Cancer to infer DNA damage response characteristics, genomic scar features, drug sensitivity, and radiation therapy outcomes. DSB repair capacity and pathway usage were validated using functional assays, including Alt-EJ reporters and droplet digital PCR quantification of microhomology-mediated repair events. Core Alt-EJ effectors such as PARP1 and POLQ were perturbed genetically and pharmacologically. Therapeutic efficacy of PARP or POLQ inhibition with or without irradiation was tested in a syngeneic OSCC model, followed by bulk tumor transcriptomics to assess pathway engagement. RESULTS: Upregulation of miR-21-5p was not only selectively detected in radioresistant OSCC, but also modulated radiosensitivity in vitro and in vivo, and was associated with inferior postradiation therapy survival. A calibrated miR-21-5p target-gene signature tracked Alt-EJ activity across patient and mouse tumors and cancer cell lines, correlated with microhomology-mediated indels and broader genomic scarring, and predicted sensitivity to clinically available PARP inhibitors. Functionally, enforced miR-21-5p expression increased Alt-EJ usage and accelerated DSB repair, whereas inhibition or depletion of key Alt-EJ effectors reduced repair efficiency and restored radiosensitivity. In vivo, Alt-EJ targeting with PARP or POLQ inhibitor abrogated miR-21-5p-driven radiation resistance; transcriptomic profiling supported suppression of Alt-EJ programs as the operative mechanism. CONCLUSIONS: These findings establish a mechanistic link between miR-21-5p activity and Alt-EJ dependence, provide a clinically deployable signature to identify Alt-EJ-dependent OSCC, and support rational combinations of Alt-EJ targeting agents with radiation therapy to overcome treatment failure and advance precision radiation oncology.

MicroRNAs

Non-smoked cannabis consumption formats and Cannabis Use Disorder severity in an illicit setting: Evidence from Chile, 2020-2024.

BACKGROUND: Cannabis Use Disorder (CUD) has become an increasing public health burden, particularly in Chile. Non-smoked cannabis formats and products have been independently associated with CUD but remain understudied in the region. This study compares CUD severity among individuals aged 12 to 65 in Chile who consume cannabis via edibles, vaporization or both versus those who exclusively smoke it. METHODS: We obtained secondary data from three waves of the Chilean National Survey on Drugs in the General Population (ENPG), a three-stage stratified probabilistic sampling design study conducted in 2020, 2022, and 2024. Our pooled cross-sectional sample included individuals (n = 3543) who reported cannabis use in vaped, edible, both vaped and edible or exclusively smoked format in the past 12 months. We used a partial proportional odds model to estimate the association between CUD severity and consumption formats. RESULTS: Cannabis vaping group showed higher odds of presenting at least mild CUD (OR = 6.21 [95% CI: 3.75-10.3]), as did the edible group (OR = 1.73 [95% CI: 1.08-2.78]) and both group (OR = 5.92 [95% CI: 2.72-12.87]), compared to exclusive smokers. However, only the vaped group demonstrated higher odds for all severity levels. CONCLUSION: Compared with exclusive smokers, users of vaporizers and/or edibles showed a stronger association with CUD. This association may be explained by consumption patterns and total THC exposure. Further research is needed to characterize the average THC exposure by consumption format, acknowledging contextual confounders such as the legal framework.

Humans

Adherence and effectiveness of multicomponent exercise fall prevention programmes across delivery formats in community-dwelling older adults: a systematic review and multilevel meta-analysis.

BACKGROUND: Multicomponent exercise is widely implemented for fall prevention in older adults, but the role of exercise adherence and delivery format in determining intervention effectiveness remains inadequately understood, particularly in analyses that account for within-study outcome dependence. METHODS: We searched five databases to 23 November 2025 for RCTs of multicomponent exercise in adults aged &#x2265;60 years. Fall outcomes were synthesised using three-level random-effects meta-analysis and meta-regression, with adherence evaluated as continuous/categorical factors and as moderator alongside delivery format, accounting for within-study effect-size dependence. RESULTS: Forty-one publications were included, comprising 36 distinct cohorts and involving 20,202 participants. Multicomponent exercise programmes significantly reduced fall incidence (IRR = 0.776, 95% CI 0.641-0.939), risk of experiencing at least one fall (RR = 0.914, 95% CI 0.858-0.974), and fall-related injury incidence (IRR = 0.754, 95% CI 0.663-0.858). Programmes achieving adherence &#x2265;75% were independently associated with greater reductions in fall incidence (IRR = 0.501, 95% CI 0.336-0.747) and fall risk (RR = 0.821, 95% CI 0.697-0.967). Mean adherence was highest in combined individual and group delivery, lower in single-format programmes, though including a group component may enhance adherence. CONCLUSIONS: Multicomponent exercise fall prevention programmes are effective for fall prevention in community-dwelling older adults, whereas evidence for their protective effects on fall-related injury outcomes remains limited. Adherence is an important factor influencing programme implementation and intervention effectiveness.

Aged

Enhancement of secondary organic aerosol formation from isoprene photooxidation by ammonia.

Ammonia (NH3) can participate in atmospheric secondary organic aerosol (SOA) formation by reacting with organic acids and carbonyl compounds in particle phase, but its influence on the gas phase chemistry remains unclear. This study performed a series of smog chamber experiments to investigate the influence of NH3 on the formation of SOA from isoprene photooxidation by OH radicals. Both gas and particle phase products were measured with a series of state-of- art instruments including a nitrate ion chemical ionization mass spectrometer (nitrate-CIMS) and high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS). Our results showed that in the presence of NH3 SOA in the chamber significantly increased, along with an enhanced oxidation of isoprene. CIMS analysis further showed that NH3 in the chamber homogeneously reacts not only with gas-phase organic acids but also with gaseous low volatility oxygenated organic molecules (OOMs) to generate extremely low volatility and ultralow volatility NH3-OOMs clusters. Quantum chemical calculation showed that NH3 can spontaneously interact with OOMs to form NH3-OOMs clusters by forming hydrogen bonds with RCOOH, R-OOH, and R-OH. These clusters can promote new particles formation and particle growth through nucleation and condensation, directly enhancing the isoprene SOA production with a contribution of 78% to the enhanced SOA. Moreover, the formation of NH3-OOMs clusters also results in more isoprene consumed by OH radicals, indirectly increasing the SOA production with a contribution of 22 % to the enhanced SOA. Our work for the first time clarified a synergetic effect of NH3 on isoprene SOA formation, which should be accounted for by models.

Aerosols

Variability and ozone formation potential of ambient non-methane hydrocarbons in a tropical semi-arid atmosphere of northwest India.

We present first-time measurements of twenty-six ambient non-methane hydrocarbons (NMHCs; C2-C8), including isoprene (C5H8), at a semi-arid site in northwest India (Ajmer; 26.45&#xb0;N, 74.64&#xb0;E), during January 2022-December 2023. Ambient samples were analyzed using a thermal desorption gas chromatography system equipped with dual flame ionization detectors. Daily total NMHC levels ranged from 6 ppbV to >100 ppbV. Most NMHCs, except isoprene, toluene, ethylbenzene, m-xylene and o-xylene, exhibited the highest levels in winter and the lowest in the monsoon. In contrast, others were highest in the pre-monsoon and toluene was highest during monsoon. These variations reflect the combined influence of emissions, chemistry and meteorology. Toluene and o-xylene were the dominant NMHCs (25 %-67 %). Correlation analyses indicated major contributions from liquefied petroleum gas (LPG) and vehicular emissions, with additional influence from urban and oil and natural gas activities. Compared with other Indian sites, NMHCs levels at Ajmer were 2-5 times lower than Ahmedabad and Udaipur and 10 times lower than Delhi. The total ozone formation potential was highest in the monsoon (about 175 ppbV) and lowest in the post-monsoon (about 55 ppbV), with dominance of o-xylene (24 %-33 %) and toluene (8 %-37 %). Propylene-equivalent concentrations were highest in the pre-monsoon (30.23 ppb C) and lowest in the post-monsoon (7.28 ppb C). Similarly, OH reactivity was highest in the pre-monsoon (19.58 s&#x207b;&#xb9;) and lowest in the post-monsoon (4.71 s&#x207b;&#xb9;), dominated by benzene and toluene. These findings emphasize the importance of NMHC chemistry in a climatically sensitive region and highlight the need for their continuous monitoring.

India

Formation of environmental persistent free radicals in soil of ammunition demolition site: Roles of 2,4,6-trinitrotoluene and heavy metals.

Environmental Persistent Free Radicals (EPFRs) are a particular type of contaminant present in soil. This study investigated the formation process, environmental behavior, and main influencing variables of EPFRs in soils contaminated with heavy metals and 2,4,6-trinitrotoluene (TNT) from an ammunition demolition site. The results showed that the concentration of total organic carbon (TOC) in the soil was negatively correlated with EPFRs (r = -0.29). In contrast, the content of TNT and copper was significantly positively correlated with EPFRs (r = 0.90 and 0.78, respectively), indicating that TNT acts as a precursor macromolecule in the formation of EPFRs in this type of contaminated soil. Transition metal Cu may be an essential carrier in EPFR production. In order to explore the possible formation mechanism of EPFRs, a simulation experiment was carried out under different temperature and light conditions. The results showed that the photolysis process of TNT was impacted by external energy sources such as heat and light. TNT was firstly adsorbed onto the surface of a transition metal (Cu), and then EPFRs were formed through further electron transfer. This is the first study to detect significant levels of EPFRs in the soil at ammunition demolition sites.

Trinitrotoluene

Advanced mitigation strategies for acrylamide formation in foods: Mechanistic insights, emerging innovations, and future perspectives.

Acrylamide is a heat-induced contaminant formed predominantly in carbohydrate-rich foods during high-temperature processing, posing significant concerns due to its potential carcinogenic, neurotoxic, and genotoxic effects. This review critically examines the mechanisms of acrylamide formation, emphasizing the role of the Maillard reaction and key precursors such as asparagine and reducing sugars, along with the influence of processing conditions including temperature, time, pH, and moisture. Various mitigation strategies are comprehensively discussed, ranging from raw material selection and genetic approaches to enzymatic treatments such as asparaginase and the application of natural and chemical inhibitors. Advances in processing technologies, including optimization of conventional thermal methods and emerging non-thermal techniques such as cold plasma and ultrasound, are evaluated for their effectiveness. The review also highlights the role of food additives, functional ingredients, and fermentation in reducing acrylamide formation. Furthermore, recent developments in analytical techniques, including chromatographic methods, biosensors, and artificial intelligence-based predictive models, are explored for improved detection and control. Risk assessment, toxicological implications, and global regulatory frameworks are also examined. Finally, future perspectives focusing on genetic engineering, personalized nutrition, and digital technologies such as AI and blockchain are discussed to support sustainable and industry-applicable mitigation strategies.

Acrylamide

Acetic acid-induced translational repression involves eIF2B body formation and Ded1 sequestration into stress granules in yeast.

Elucidating the physiological impact of acetic acid stress and the corresponding yeast responses is essential for advancing fundamental biology and improving industrial alcoholic fermentation. Despite numerous genome-wide studies, information on the effects of acetic acid stress on yeast translational regulation remains limited. We found that a sublethal concentration of acetic acid (35 mM, 0.2% v/v) causes translational repression, accompanied by the formation of eIF2B bodies and the phosphorylation of eIF2&#x3b1;, both of which are involved in the regulation of translation initiation. Acetic acid also caused the sequestration of Ded1, a DEAD-box RNA helicase crucial for translation initiation, into stress granules. Removal of acetic acid restored translational activity and the proper localization of eIF2B and Ded1, indicating the reversibility of acetic acid-induced translational repression. Furthermore, when yeast cells were pretreated with 0.05% acetic acid, translational repression under subsequent 0.2% acetic acid stress was attenuated in wild-type cells but not in hrk1&#x394; cells. This indicates that Hrk1, a Pma1 activator, is required to sufficiently enhance tolerance to acetic acid-induced translational repression. These findings provide novel insights into the physiological effects of acetic acid stress on translational activity and translation-related factors in yeast cells.

Saccharomyces cerevisiae

Proteomic characterization of the acquired enamel pellicle under acidic challenges at early and mature formation stages.

OBJECTIVES: This study aimed to characterize acquired enamel pellicle (AEP) proteomic changes after exposure to citric acid (CA) and hydrochloric acid (HCl) under different pellicle formation times (3 and 120&#x202f;min) in the same volunteers. DESIGN: Nine healthy volunteers participated in this randomized crossover in vivo study. The AEP was allowed to form for 3 or 120&#x202f;min and subsequently exposed for 10&#x202f;s to deionized water (control), 1% CA (pH 2.5), or 0.01&#x202f;M HCl (pH 2.0). Pellicle samples were collected, followed by protein extraction, tryptic digestion, and analysis by nanoliquid chromatography (nanoLC) coupled to mass spectrometry (MS) with MSE (data-independent acquisition; nanoLC-MS&#x1d31;). Label-free quantitative proteomics were performed for relative quantification using t-test (p&#x202f;<&#x202f;0.05). RESULTS: At 120&#x202f;min, CA exposure markedly reduced several typical AEP proteins, especially acidic proline-rich proteins (PRPs). Conversely, basic PRPs were upregulated, suggesting acid-resistance protein signature. At 3&#x202f;min, basal-layer proteins (PRPs, cystatins, histatins and mucins) were more abundant. Hemoglobins increased 6-8-fold (up to 150-fold in 3&#x202f;min control), suggesting association with early pellicle formation and an acid-resistant protein signature. CA exposures for 120&#x202f;min also upregulated typical AEP proteins (PRPs, mucins, cystatins, immunoglobulins), while HCl exposure depleted albumins and lactotransferrin. CONCLUSION: Intrinsic and extrinsic acids induce distinct proteomic signatures in the AEP. Hemoglobin and PRPs appear consistently enriched in the early pellicle layer, reflecting an initial acid-resistant protein signature. These findings provide new insights into the molecular remodeling of the AEP following intrinsic and extrinsic acid exposure, highlighting proteins potentially involved in early-stage pellicle formation.

Humans