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Comparison of black carbon measurements using filter-specific reference transmittance to those using lab blanks or an average of unloaded filters.

Filter-based optical techniques compare light transmission intensities between loaded (I) and unloaded (I0) filters as a measure of light-absorbing mass for subsequent estimations of equivalent black carbon (eBC). We analyzed 5,379 15 mm Teflon filters from the Household Air Pollution Intervention Network (HAPIN) trial to assess the influence that different methods of I0 estimations have on eBC measures. We compared eBC measurements using filter-specific I0 values (Method 1) to those using three other methods of I0 estimation: the lab blank scan from a given session (Method 2), the average of all pre-sample filter scans (Method 3), and the average of all lab blank filter scans (Method 4). We assessed the agreement between Method 1 and the alternative methods using Bland-Altman analysis. We also assessed the relationship between Method 1 and the alternative methods across the complete measurement range and after stratifying exposure data into quartiles according to Method 1 eBC exposures. The mean (SD) personal eBC exposure for Method 1 was 7.8 μg/m3 (5.9), and exposures ranged from 1.3 to 46.8 μg/m3. Compared to Method 1, eBC using Methods 2, 3, and 4 were higher by 0.7 μg/m3, 0.1 μg/m3, and 0.7 μg/m3, respectively. The performances of linear regression models between Method 1 and all other methods were moderate to strong (R2 range: 0.42-0.93) in the second, third, and fourth quartiles; however, the models in the first quartile (eBC range: 1.3-2.9 μg/m3) performed poorly (R2 = 0.25-0.26), with error approximately 25% of the mean. Our findings suggest that, in most instances, conventional methods for obtaining I0 values can be used to sufficiently characterize eBC; however, analyzing filters before sampling adds appreciably to the accuracy of eBC estimations in lower concentration settings.Implications: Filter-based optical techniques compare light transmission intensities between loaded (I) and unloaded (I0) filters as a measure of light-absorbing mass for subsequent estimations of equivalent black carbon (eBC). To assess the influence that different methods of I0 estimations have on eBC measures, we analyzed 5,379 15 mm Teflon filters from the Household Air Pollution Intervention Network (HAPIN) trial. Our findings suggest that, in most instances, conventional methods for obtaining I0 values can be used to sufficiently characterize eBC; however, analyzing filters before sampling adds appreciably to the accuracy of eBC estimations in lower concentration settings.

Soot

A novel urease-producing strain effectively induces cadmium biomineralization under low-temperature stress.

Microbially induced carbonate precipitation (MICP) has been widely used to immobilize Cadmium (Cd) in contaminated soils in mining-affected regions. However, its remediation efficacy under low-temperature stress, as well as the nucleation process that regulates Cd biomineralization via carbonate precipitation by psychrophilic bacteria, has yet to be investigated. Here, we isolated Pseudomonas sp. J-6, a novel urease-producing strain from tailings in high-altitude cold regions, exhibiting unparalleled cold adaptability at 5 °C and achieving 95.85 % Cd removal efficiency by MICP at 10 °C. Furthermore, the coprecipitation process of Ca1-xCdxCO3 was clarified through the continuous observation of the precipitates after the low-temperature MICP reaction. The crystal morphology transitioned from loose vaterite in the early stage to a dense square-block morphology in the middle stage. Cd2+ progressively shifted from a surface-bound state to lattice incorporation, ultimately resulting in the formation of stable Cd-substituted calcite crystals. In this process, low temperatures led to the formation of larger, highly ordered Cd-substituted calcite crystals, thereby strengthening Cd sequestration and its long-term stability. In addition, under low-temperature stress, Pseudomonas sp. J-6 induced MICP reaction decreased the bioavailable Cd in alpine slag soil by 44.85 % and enhanced physical properties. In the freeze-thaw cycles, the remediation efficiency remained stable. This study clarified the biomineralization potential in high-altitude cryogenic environments and the nucleation process of Cd biomineralization by psychrophilic bacteria-induced carbonate precipitation, filling a critical research gap in its application under extreme conditions and highlighting its promise for sustainable remediation of heavy metal pollution under low-temperature stress.

Cadmium

A review on the environmental distribution, toxic effects, bioaccumulation characteristics and risk assessment of short-chain chlorinated paraffins.

Chlorinated paraffins (CPs) are synthetic chemicals, widely used as flame retardants and plasticizers. As emerging contaminants, short chain chlorinated paraffins (SCCPs) have attracted tremendous attention due to their persistence, chronic toxicity, long-range transport potential and bioaccumulation potential. This review synthesizes global data on SCCPs' environmental occurrence, toxicological impacts, and bioaccumulation characteristics. SCCPs are ubiquitously detected in various environmental media, including water, sediment, air, soil, and biota. Ecotoxicological studies reveal that SCCPs have lethality, carcinogenicity, growth and developmental toxicities, organs toxicities and endocrine-disrupting effects across species, which pose risks to ecological systems and human health. In addition, the bioaccumulation effects of SCCPs in terrestrial and aquatic ecosystems were analyzed, and proposed the key factors affecting the bioaccumulation of SCCPs. Finally, the risk assessment of SCCPs contamination in the surface water and the soil was carried out, and all soil and most water bodies were found to be low risk. The present study could provide scientific basis and reference for environmental management of CPs products.

Paraffin

Genome-wide characterisation of the myosin light chain gene family in Chinese perch (Siniperca chuatsi) and its expression patterns in muscle fibre types and injury response.

The Class II myosin light chain (myl) genes in Chinese perch (Siniperca chuatsi) have not yet been systematically characterised, and relationships with muscle fibre specification, development, and injury-associated remodelling remain unclear. In this study, fast and slow muscle fibres were initially distinguished using myofibrillar ATPase histochemistry. Subsequently, genome-wide mining identified 16 Class II myl genes, comprising eight essential and eight regulatory light-chain subunits. Their conserved-domain features, chromosomal distribution, phylogenetic relationships and expression profiles were analysed. Transcriptomic profiling showed that summed myl transcript abundance was higher in fast muscle than in slow muscle, accounting for 67.2% of the pooled myl transcript pool across the two muscle types (paired t-test, raw P = 0.036). mylpfa, myl1 and mylz3 were the major fast-muscle-associated genes, whereas myl10, myl2b and myl13 were preferentially expressed in slow muscle at the transcript level. These patterns support these genes as candidate fibre-type-associated expression markers. Developmental profiling identified stage-associated myl expression patterns, including a possible expression shift between mylpfb and mylpfa. In the descriptive injury-repair time course (d0-d7), FPKM profiles indicated that fast-muscle-associated genes (mylpfa, mylz3 and myl1) were lower at d1 and recovered by d3, whereas several slow-muscle-associated genes showed biphasic transcript-level increases. The slow-muscle-associated RLC gene mylpfb showed a delayed expression peak at d7. Notably, the embryonic isoform myl6l showed a modest increase from approximately 2 FPKM at d0 to 4-5 FPKM after injury, suggesting a possible injury-associated expression pattern that requires further validation. Together, these findings provide a genome-wide description of the Chinese perch myl gene family and identify candidate fibre-type-associated genes and descriptive injury-associated isoform expression patterns.

Animals

Diagnostic utility of high-risk HPV polymerase chain reaction-based testing in head and neck FNA specimens with indeterminate cytomorphology.

BACKGROUND: Fine-needle aspiration (FNA) is critical in the initial diagnosis of many high-risk human papillomavirus (HR-HPV)-associated, metastatic oropharyngeal squamous cell carcinomas. Updated guidelines recommend HR-HPV-specific polymerase chain reaction (PCR) analysis over p16 immunohistochemistry on FNA specimens because p16 performs poorly on cytology material. PCR-based assays on liquid cytology material have demonstrated excellent analytic performance; however, the diagnostic utility of a positive HR-HPV PCR result in specimens with indeterminate cytomorphology remains uncharacterized. METHODS: The authors retrospectively identified 279 head and neck FNA specimens that had paired HR-HPV PCR testing on residual liquid cytology material over a 5-year period. The positive predictive value for histopathologically confirmed squamous cell carcinoma on surgical follow-up was calculated within each cytologic interpretive category. RESULTS: The HR-HPV PCR results were positive in 50.2% of specimens, negative in 40.9%, and indeterminate in 9.0%. The HR-HPV positivity rate ranged from 0% in specimens categorized as negative for malignancy to 57.3% in cytologically positive specimens, with 19.0%, 41.2%, and 50.0% positivity in the atypical, suspicious, and nondiagnostic categories, respectively. Among cytologically indeterminate specimens with positive HR-HPV PCR results (n = 14), the positive predictive value was 100% (95% confidence interval, 78.5%-100.0%). Blinded slide review additionally identified 15 cytologically positive specimens in which the definitive malignant interpretation depended substantially on HR-HPV positivity; all 15 were confirmed as squamous cell carcinoma. CONCLUSIONS: A positive HR-HPV PCR result on liquid cytology material carries a positive predictive value of 100% for malignancy in cytologically indeterminate head and neck FNA specimens. These findings support integrating HR-HPV PCR analysis into routine cytologic interpretation with the potential to upgrade some indeterminate specimens to malignant when HR-HPV is detected, expediting definitive treatment and sparing patients additional, invasive sampling.

Humans

Application of 13C MRS demonstrates carbohydrate feeding spares muscle but not liver glycogen utilization during high-intensity interval exercise.

We examined liver and muscle glycogen utilization during high-intensity interval cycling, and the impact of carbohydrate (CHO) feeding, using noninvasive 13C magnetic resonance spectroscopy (MRS). Following 24 h of standardized dietary intake, nine male cyclists completed 8 &#xd7; 5-min intervals (1-min recovery), ingesting either placebo (PLA), 60 g maltodextrin (CHO), or 60 g maltodextrin plus caffeine, taurine, l-theanine, l-citrulline, and citicoline (CHO+) in a randomized crossover design. 13C MRS and 1H imaging were performed pre- and postexercise to determine liver and muscle glycogen and liver volume, respectively. Liver glycogen utilization was not significantly different between trials (P = 0.101) despite lower postexercise plasma glucagon concentrations in CHO and CHO+ (P = 0.001). In contrast, muscle glycogen utilization was significantly lower (&#x223c;40%) with CHO feeding compared with PLA (P = 0.006), yet this sparing effect was not evident with CHO+ (P = 0.073) in accordance with a higher mean power output during the late intervals (+2.8%, P = 0.046). Plasma glucose was comparable between trials (P = 0.175), whereas plasma lactate was higher in CHO+ versus CHO (P = 0.003), alongside lower blood bicarbonate (P = 0.005), base excess (P < 0.001), and total CO2 (P = 0.004). These findings demonstrate preferential use of skeletal muscle glycogen during high-intensity interval training (HIIT), which is attenuated under conditions of CHO feeding. This sparing effect is, however, not evident with the coingestion of a caffeine-containing multi-ingredient blend, potentially due to an increased capacity to sustain higher power outputs resulting in greater glycogen utilization.NEW & NOTEWORTHY Using 13C MRS, we provide data demonstrating preferential use of skeletal muscle glycogen during HIIT. Furthermore, data show muscle glycogen utilization is attenuated with CHO feeding, yet sparing is not evident when coingesting a caffeine-containing formulation, potentially reflecting increased capacity to perform more total work rather than a direct metabolic effect of caffeine. In contrast, liver glycogen utilization was not significantly different with CHO feeding despite a modest reduction of &#x223c;5 g versus placebo.

Male

Topical Carboxytherapy as an Adjunct to Skin Recovery Post-CO2 Laser Fractional Resurfacing.

BACKGROUND: Topical carboxytherapy, a transcutaneous carbon dioxide (CO2) delivery system, may support skin repair and regeneration, yet its role as an adjunct to fractional laser treatment remains underexplored. OBJECTIVE: To investigate the effectiveness and safety of topical CO2 mask (CO2Lift&reg; Carboxy Gel, Lumisque Skincare) in supporting skin recovery and improving clinical outcomes following fractional CO2 laser resurfacing. METHOD: This 12-week randomized, placebo-controlled trial evaluated mild-to-moderate photoaging (n=6 females only). Participants received either topical carboxytherapy (n=4) or standard care (n=2). Assessments included VISIA-CR imaging, biophysical measurements, investigator ratings, and paired (baseline and 4-week) skin biopsies. RESULTS: Topical carboxytherapy accelerated recovery and was well-tolerated, with no major adverse events. VISIA-CR imaging showed accelerated erythema resolution, transepidermal water loss normalized more rapidly, and pH remained stable. Skin histology at week 4 revealed epidermal thickening and rete ridge formation with topical carboxytherapy vs placebo. Investigator ratings demonstrated significantly improved healing, global assessment, and global aesthetic improvement scale scores, with trends toward improvement in photodamage, rhytides, and pigmentation. CONCLUSION: Adjunctive topical carboxytherapy after fractional CO2 resurfacing accelerated healing, improved barrier recovery, and overall aesthetic outcomes. Larger studies are needed to confirm these findings.

Humans

Prognostic effect of serum glial fibrillary acidic protein and neurofilament light chain for predicting progression independent of relapse activity in multiple sclerosis: A systematic review.

BACKGROUND: Progression independent of relapse activity (PIRA) is increasingly appreciated as one of the important factors contributing to disability accumulation in MS. sGFAP and sNfL could represent markers reflecting two separate biological processes related to relapse-independent progression in MS. OBJECTIVE: To perform a systematic review of the literature on blood GFAP and/or NfL measured in relation to PIRA or other similar relapse-independent progression endpoints in people with MS. METHODS: PubMed, Scopus, and Web of Science databases were searched from inception to 1 June 2026. The eligible studies were original human studies measuring blood GFAP and/or NfL concentrations in serum, plasma, or any other type of blood-derived material and assessing PIRA, PIRMA, CDP/CDW without relapses, relapse-free EDSS progression, non-inflammatory progression, or comparable relapse-independent disability worsening outcomes. Methodological quality was assessed according to the Newcastle-Ottawa scale and the QUIPS instrument for bias detection in the body of evidence on prognostic factors. Due to heterogeneity of outcomes, biomarker measurements and effect estimates, results were synthesized qualitatively rather than quantitatively. RESULTS: After removing duplicates, 1206 records were screened, followed by full-text review of 120 reports. A total of 18 reports were included. Overall, sGFAP was associated more frequently with PIRA or PIRA-like disability progression, particularly in cohorts with suppressed or limited overt inflammatory activity. Evidence for sNfL was more variable and context-dependent: several studies reported associations with PIRA-like or relapse-independent disability worsening when acute inflammatory activity was absent, suppressed, or analytically separated, whereas other studies reported negative or inconclusive findings. Negative or inconclusive results were reported by several articles, particularly when broad outcomes were evaluated or the study population was small. CONCLUSION: Blood GFAP and NfL give complementary but non-interchangeable information concerning PIRA in MS patients. The existing evidence base does not allow us to perform meta-analysis because of heterogeneity in terms of outcomes, standardization of biomarkers, and treatment context. Further prospective investigations with uniform criteria will be necessary for their use as biomarkers of PIRA in clinical settings.

Humans

Oxidative potential of fresh vs. O&#x2083;-aged PM2.5 across urban and rural sources in China.

Fine particulate matter (PM2.5) is a major health risk, yet its impacts are still largely assessed using mass concentration, which does not capture toxicity. Recently, oxidative potential (OP) has emerged as a more relevant metric, reflecting the ability of particles to generate reactive oxygen species. A current challenge, especially in China, is understanding how emission sources and ozone (O3) aging affect PM2.5 toxicity, given that O3 is an increasingly important pollutant there. A work by Ma and co-workers published in J. Environ. Sci. (doi.org/10.1016/j.jes.2024.04.023) addressed this by evaluating the OP of fresh and O3-aged PM2.5 from multiple sources in China using the dithiothreitol (DTT) assay. Biomass burning particles exhibited the highest OP, up to 35 times greater than suburban PM2.5, driven by water-soluble organics and transition metals. While O3 aging generally reduced OP, it also induced complex chemical transformations. These findings highlight that PM2.5 toxicity is dynamic and source-dependent, underscoring the need to move beyond mass-based air quality metrics.

Particulate Matter

From buffalo to human: Klebsiella pneumoniae in high-somatic cell count milk as an overlooked link in the one health chain.

High somatic cell count (SCC) is a critical indicator of udder health and milk quality in buffalo milk production. However, in many low-income regions, SCC monitoring is often underemphasized, allowing a proportion of high-SCC buffalo milk to enter the food chain and potentially compromising food safety and public health. Klebsiella pneumoniae (K. pneumoniae) is a common zoonotic pathogen found in high-SCC milk, yet systematic investigations into the prevalence and characteristics in high-SCC buffalo milk remain limited. In this study, 23 K. pneumoniae strains were screened out from 460 bacterial isolates obtained from high-SCC buffalo milk samples from Guangxi, China, with an isolation rate of 5.0%. These isolates were comprehensively characterized using whole-genome sequencing and comparative genomic analyses. The results revealed that 78.26% (18/23) of the isolates shared high genomic similarity with the human reference strain ATCC 13883, and the ST37 clone exhibited a pronounced potential of cross-species transmission. All isolates harbored core adhesion factors and intrinsic resistance genes. Notably, several strains displayed high-risk features: strain 419 carried the K1 capsular serotype, strain 326 possessed a complete yersiniabactin synthesis gene cluster, and strain 320 exhibited a multidrug-resistant phenotype. Phenotypic assays further demonstrated a positive correlation between biofilm formation capacity and virulence in Galleria mellonella. Metabolic pathway enrichment analyses suggested that K. pneumoniae has undergone substantial adaptation to the nutrient-rich buffalo milk environment. Collectively, these findings confirm that raw high-SCC buffalo milk serves as a significant reservoir for high-risk zoonotic K. pneumoniae. While industrial thermal processing effectively eliminates viable pathogens, the resilient antimicrobial resistance determinants within these isolates pose a persistent risk of horizontal gene dissemination along the food chain, providing critical evidence for enhancing pre-processing milk quality regulations within a One Health framework.

Animals

The role of adjunctive aqueous suppressants for anti-vascular endothelial growth factor therapy: A systematic review.

Our goal is to determine whether adjunctive aqueous suppressants (topical &#x3b2;-blockers, carbonic anhydrase inhibitors, or oral acetazolamide) enhance outcomes of anti-vascular endothelial growth factor (anti-VEGF) therapy for diabetic macular edema (DME), retinal vein occlusion (RVO), and neovascular age-related macular degeneration (nAMD), focusing on retinal thickness, visual acuity, injection burden, intraocular pressure (IOP), and safety. DME, RVO, and nAMD are leading causes of vision loss treated with repeated intravitreal injections, yet many eyes show persistent fluid. Aqueous suppressants are inexpensive and widely available, with potential to prolong intravitreal drug residence and improve outcomes, but their clinical value remains uncertain. Following a registered protocol, we searched 4 databases (January, 2000 toMay, 2025) for randomized and comparative studies evaluating adjunct aqueous suppressants with anti-VEGF therapy. Primary outcome was change in retinal thickness; secondary outcomes included visual acuity, injection burden, IOP, and adverse events. Risk of bias was assessed and findings synthesized narratively. Twelve studies (7 randomized trials; 495 eyes) met inclusion criteria. In DME, 3 of 4 trials showed greater thickness reduction with adjunctive dorzolamide (&#xb1;timolol), although visual gains were inconsistent. In RVO, 1 trial suggested transient anatomical benefit, whereas oral acetazolamide showed no added effect. In nAMD, adjunctive dorzolamide-timolol reduced residual fluid in refractory cases without visual or treatment-sparing benefit. Topical therapy produced modest IOP reductions without serious adverse events. Adjunct aqueous suppressants may provide limited short-term anatomical benefit, particularly in DME and refractory nAMD, but consistent functional or durability effects are not found in this study. Larger, longer-term randomized studies are needed.

Humans

Acetazolamide to prevent ventilatory drive withdrawal in REM sleep apnoea: a randomised controlled trial.

BACKGROUND: Obstructive sleep apnoea (OSA) pathogenesis during rapid-eye movement (REM) sleep has been linked to dips in ventilatory drive and downstream genioglossus hypotonia. The carbonic anhydrase inhibitor acetazolamide is known to increase ventilatory drive and improve OSA severity. Therefore, we tested the effect of acetazolamide on REM-predominant OSA severity (apnoea hypopnoea index (AHI) and hypoxic burden, co-primary outcomes) and underlying physiological mechanisms (ventilatory drive, ventilation and pharyngeal muscle activity). METHODS: 11 participants with REM-predominant OSA per baseline polysomnography (REM AHI/non-REM AHI&#x2265;2) were allocated to receiving acetazolamide 500&#x2009;mg for three nights (first night at half dose) or placebo according to a randomised, crossover, double-blind design. Detailed physiological polysomnography with recording of diaphragm and genioglossus electromyography was conducted after each intervention, with a 1-week washout in between. RESULTS: As hypothesised, acetazolamide reduced AHI by 35.5% (95% CI 23.1% to 46.3%) and hypoxic burden by 35.9% (95% CI 21.1% to 48.4%) vs placebo (p<0.001), meeting the primary endpoint. Mechanistic analysis in REM revealed that, unexpectedly, acetazolamide did not mitigate dips in ventilatory drive versus placebo (first decile (+0.1 (-1.0 to 1.3) L/min, p=0.8). Rather, acetazolamide reduced collapsibility (increased ventilation at eupneic drive: +1.4 (1.2 to 1.8) L/min) and raised muscle responsiveness (ventilation vs drive slope: +32 (25 to 41) %ventilation/drive, p<0.001; genioglossus versus drive slope: +0.33 (0.13 to 0.54) %max/(L/min), p=0.001). CONCLUSIONS: Acetazolamide modestly improved REM OSA, with meaningful improvements in upper airway physiology, but failed to mitigate the dips in ventilatory drive responsible for REM OSA. TRIAL REGISTRATION NUMBER: NCT05589792.

Humans

Increasing gut short-chain fatty acids protects intestinal barrier function but does not spare muscle glycogen or impact aerobic performance.

Animal studies suggest gut microbiota-derived short-chain fatty acids (SCFA) provide an intestinal barrier-protecting, glycogen-sparing energy source that increases aerobic endurance performance, but confirmation in humans is needed. This study aimed to determine whether increasing colonic SCFA availability impacts intestinal barrier function, substrate metabolism, muscle glycogen and aerobic performance in healthy adults. Using a randomized, double-blind, crossover design 12 active men (age 18-30&#xa0;years;40.0&#xa0;&#xb1;&#xa0;7.1&#xa0;mL/kg/min) performed prescribed exercise and consumed a provided diet supplemented with acetylated and butyrylated high-amylose maize starch engineered to deliver SCFA to the colon (HAMS-A/B) or low-amylose maize starch (LAMS) for 7 days, separated by a 2 week washout. Indirect calorimetry, stable isotopes and blood, muscle and urine biomarkers were measured on intervention day 8 while participants completed 90&#xa0;min of steady-state cycle ergometry (ExSS; 60 &#xb1; 5%) followed by a 5&#xa0;km treadmill time trial. HAMS-A/B, relative to LAMS, increased faecal and serum SCFA. Multiple markers of intestinal barrier damage and permeability were lower, and the respiratory exchange ratio during ExSS was higher (0.02 [95% confidence interval (CI): 0.01, 0.03], Ptreatment&#xa0;<&#xa0;0.001) following HAMS-A/B versus LAMS. However no between-treatment difference in glucose turnover, muscle glycogen depletion (14&#xa0;&#xb5;mol/kg/g dry wt. [95% CI: -116, 143], Pinteractio n&#xa0;=&#xa0;0.613) or TT performance (5&#xa0;s [95%CI: -44, 54], Ptreatment&#xa0;=&#xa0;0.816) was observed. Increasing colonic and circulating SCFA modestly altered substrate oxidation and preserved intestinal barrier function during endurance exercise. However effects were not sufficient to spare muscle glycogen or increase aerobic endurance performance, leaving the practical relevance unclear and underscoring challenges inherent in translating promising preclinical findings to humans. KEY POINTS: Animal studies suggest gut microbiota-derived short-chain fatty acids (SCFA) provide an intestinal barrier-protecting, glycogen-sparing energy source that increases aerobic endurance performance, but confirmation in humans is lacking. A gut microbiota-targeted dietary supplementation strategy was used to deliver SCFA to the colon and successfully increased colonic and systemic SCFA concentrations in healthy, physically active adults before and during an endurance exercise bout and aerobic performance test. Increasing colonic and systemic SCFA availability preserved intestinal barrier function but did not impact glucose turnover, alter protein expression in muscle or spare muscle glycogen during endurance exercise. Increasing colonic and systemic SCFA availability did not impact aerobic endurance performance.

Humans

Associations of clinical and laboratory parameters with pediatric urolithiasis composition: A retrospective, single-center study.

OBJECTIVE: To investigate demographic, clinical, and laboratory factors associated with distinct stone compositions in children. METHODS: This retrospective study included 237 children aged <14 years who underwent stone composition analysis between July 2008 and November 2023. Demographic, clinical, and laboratory data were collected, and propensity score matching (PSM) was used to control for confounding factors. RESULTS: The urate component (uric acid anhydrous, ammonium acid urate, and sodium urate) was most prevalent in infants, males, and non-Han children, whereas the calcium oxalate component predominated in older children. Analysis of coexisting components revealed urate is the most common partner to calcium oxalate (67.6%), and vice versa (82.8%). Struvite most frequently coexisted with carbonate apatite (60%), while carbonate apatite most often coexisted with calcium oxalate (54%). After PSM, the urate component was independently associated with host metabolic dysregulation, including lower high-density lipoprotein (&#x3b2; = -0.175, 95% CI: -0.279 to -0.071, p = 0.001) and with coagulation dysfunction, as evidenced by a prolonged prothrombin time (&#x3b2; = 0.595, 95% CI: 0.125 to 1.064, p = 0.014). Additionally, preoperative urinary tract infection (UTI) and congenital urinary tract anomalies were independently associated with both carbonate apatite and struvite components, with directionally consistent but quantitatively unstable signals in the struvite cohort, whereas the calcium oxalate component exhibited an inverse association with UTI (OR = 0.156, 95% CI: 0.030 to 0.819, p = 0.028). Furthermore, the carbonate apatite component was also independently associated with an elevated systemic immune-inflammation index (&#x3b2; = 416.53, 95% CI: 60.05 to 773.01, p = 0.024) and systemic inflammation response index (&#x3b2; = 1.286, 95% CI: 0.086 to 2.487, p = 0.038). CONCLUSION: Urate component was prevalent in infants, males, and non-Han children, whereas calcium oxalate predominated in older children. After adjusting for confounders, urate composition was associated with metabolic abnormalities, the carbonate apatite component was linked to infection and anatomical malformations, and a similar directional pattern was observed in the struvite cohort.

Humans

Enhancing Hemoglobin Bart's hydrops fetalis syndrome prevention: a single-tube multiplex real-time PCR assay for the comprehensive detection of four significant &#x3b1;0-thalassemia deletions (--SEA, --THAI, --CR, and --SA) found in Thailand.

BACKGROUND: Hemoglobin (Hb) Bart's hydrops fetalis is a major public health concern in Southeast Asia, particularly in Thailand. Current screening strategies target the two most common &#x3b1;0 -thalassemia deletions (--SEA and --THAI). METHOD: In this study, we developed a single-tube multiplex real-time PCR assay for the simultaneous detection of four clinically relevant &#x3b1;0-thalassemia deletions (--SEA, --THAI, --CR, and --SA). The assay was validated using 538 clinical samples with diverse thalassemia genotypes and compared against conventional gap-PCR as the reference method. Analytical performance, including sensitivity, specificity, and limit of detection (LOD), was evaluated. In addition, clinical utility was assessed in 22 prenatal diagnosis cases at risk of Hb Bart's hydrops fetalis. RESULTS: The study cohort demonstrated substantial genetic heterogeneity, comprising 43 distinct genotypes. The developed assay achieved 100% sensitivity and specificity for all targeted deletions, with complete concordance with gap-PCR results. No cross-reactivity was observed with &#x3b1;+-thalassemia. The assay demonstrated a high analytical sensitivity with a LOD of 9.76&#x2009;&#xd7;&#x2009;10-3&#x2009;ng per reaction. Whereas in prenatal diagnosis, all 22 fetal genotypes were accurately identified, including five cases of homozygous --SEA and one rare compound heterozygous --SEA/--CR fetus. CONCLUSIONS: This study presents a rapid, accurate, and cost-effective multiplex real-time PCR assay capable of detecting both common and rare &#x3b1;0-thalassemia deletions in a single reaction. The assay demonstrates strong potential for implementation in routine clinical laboratories and large-scale population screening, contributing to improved prevention and control of severe thalassemia syndromes in high-prevalence regions.

Humans

Effect of flavored on!&#xae; nicotine pouch products on smoking behaviors: A sequential, multiple assignment, randomized controlled trial.

PURPOSE: To evaluate whether flavored versus unflavored nicotine pouch (NP) access affects cigarette reduction and smoke exposure among adults who smoke daily, and whether delayed flavor introduction affects these outcomes. METHODS: Adults who smoked &#x2265;&#x2009;5 cigarettes/day (CPD) with interest in replacing cigarettes with NPs were enrolled in a remote, six-week, sequential multiple assignment randomized trial (n&#x2009;=&#x2009;402 randomized; n&#x2009;=&#x2009;400 analyzed). Participants were randomized to immediate access to seven NP flavors (Flavor), unflavored-only access for six weeks (Original), or unflavored-only for three weeks followed by flavor access (Delayed Flavor). Primary outcomes were &#x2265;&#x2009;50% reduction in weekly mean expired-air carbon monoxide (CO) from baseline and mean CO at Week 6. Secondary outcomes included &#x2265;&#x2009;50% CPD reduction, mean CPD, CO-verified 7-day abstinence, and incident smoke-free days. RESULTS: At Week 6, Flavor and Original did not differ in &#x2265;&#x2009;50% CO reduction (14.3% vs 14.2%; IRR=1.0, 95% CI=0.6-1.8) or mean CO (18.3 vs 16.5&#x2009;ppm; &#x3b2;=1.9, 95% CI=-1.3-5.0). CPD decreased across groups by Week 6, with no differences between Flavor and Original in &#x2265;&#x2009;50% CPD reduction (50.3% vs 51.6%; IRR=1.0, 95% CI=0.8-1.2) or CO-verified abstinence (9.3% vs 8.9%; IRR=1.0, 95% CI=0.5-2.2). Flavor increased smoke-free days early, with attenuation over time. Among Week 3 non-responders, delayed flavor access increased &#x2265;&#x2009;50% CPD reduction at Week 6 (33.3% vs 18.6%; IRR=1.8, 95% CI=1.0-3.2). CONCLUSIONS: NP access supported cigarette reduction regardless of flavor availability, but flavors may accelerate smoke-free days and improve response among individuals who do not reduce cigarette consumption with unflavored products alone.

Humans

Strategy for enhanced production of A40926B0 in Nonomuraea gerenzanensis using an efficient CRISPR/AsCas12f1 system.

The global emergence of vancomycin-resistant Gram-positive pathogens underscores the urgent need for efficient production of novel lipoglycopeptide antibiotics. Dalbavancin, a last-resort therapeutic agent, relies on its key biosynthetic precursor A40926B0, whose industrial manufacture is severely limited by the low yield of wild-type Nonomuraea gerenzanensis and inefficient genetic tools for this rare actinomycete. Here, we developed a high-efficiency CRISPR/AsCas12f1 genome editing system and applied systematic metabolic engineering to boost A40926B0 biosynthesis. First, conjugation conditions were optimized to elevate the transfer efficiency in N. gerenzanensis D11. The hypercompact AsCas12f1 nuclease showed markedly lower cytotoxicity than SpCas9 and enabled 100% gene deletion efficiency with preferred PAMs (TTTG, CTTG, GTTG). Second, we strengthened the shikimate pathway via multiple genetic strategies: overexpressing feedback-resistant DAHP synthase (aroG fbr ) and chorismate mutase/prephenate dehydrogenase (tyrA fbr ), as well as knocking out pheA. This manipulation blocks the phenylalanine synthetic branch and redirects metabolic flux toward the l-tyrosine branch. Third, we engineered the branched-chain fatty acid (BCFA) pathway via promoter replacement of bkdA2B2C2, LipAB, fabF and deletion of acdH to enhance isododecanoyl side-chain supply. The combinatorial engineering yielded strain B-13, which produced 1740&#x202f;mg/L A40926B0 in shake flasks. Finally, 50-L fed-batch fermentation with continuous maltodextrin feeding further increased the titer to 1817&#x202f;mg/L, the highest reported titer to date. This work establishes a robust CRISPR editing tool for N. gerenzanensis and provides valuable engineering references for precursor-oriented strain improvement targeting lipoglycopeptide antibiotics, offering insights for the industrial scale production of A40926B0.

A40926B0

The knee-ankle link: impact of knee varus severity on distal joint malalignment and concomitant pathologies.

BACKGROUND: Knee varus deformity is traditionally managed as an isolated joint pathology; however, persistent distal symptoms following proximal realignment suggest a more extensive kinetic chain dysfunction. The degree to which knee varus severity dictates distal malalignment and secondary pathologies remains poorly quantified in the current literature. METHODS: This systematic review and meta-analysis were conducted in accordance with PRISMA 2020 guidelines (PROSPERO: CRD420261363327). A comprehensive search of PubMed, Embase, Web of Science, and the Cochrane Library was performed from inception to April 2026. Studies examining the relationship between knee varus (HKA angle) and radiographic distal alignment or pathologies were included. Data synthesis utilized random-effects models, with prevalence analyzed via generalized linear mixed models (GLMM). RESULTS: Fourteen studies were included in the final synthesis. While pooling of continuous radiographic parameters was limited by high statistical heterogeneity in Talar Tilt (I2&#xa0;=&#xa0;96.5%), individual large-cohort data (Huang et al.) indicated that severe knee varus (HKA&#xa0;>&#xa0;10&#xb0;) was associated with increased odds of concomitant ankle osteoarthritis (OR 2.29; 95% CI 1.28-4.11) and a specific cohort prevalence of 37.1%. Furthermore, single-arm prevalence data revealed divergent trends across different study populations, with compensatory hindfoot valgus reaching 69.9% in some cohorts and rigid varus up to 63.9% in others. CONCLUSIONS: Severe genu varum is associated with distal kinetic chain alterations and concomitant ankle pathologies. However, due to the extreme heterogeneity and divergent distal adaptations observed across different cohorts, standardized knee-centric protocols may be insufficient. Further longitudinal and interventional studies are required to establish phenotype-specific rehabilitation guidelines.

Humans