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Mechanisms of high-humidity hot air impingement blanching (HHAIB) on microbial counts, functional properties, phenolic profile transformation, and volatile compounds in celery stalks (Apium graveolens L.).

In this study, celery stalks were pretreated with different durations (0-150 s) of high-humidity hot air impingement blanching (HHAIB), followed by far-infrared radiation assisted pulsed vacuum freeze-drying (FIR-PVFD) at 60, 65, and 70 °C. The effects of HHAIB on the physicochemical properties, composition and transformation of phenolic compounds, volatile components, and antioxidant capacity of FIR-PVFD-dried celery stalks were systematically investigated. The results showed that HHAIB not only effectively reduced the counts of total mesophilic aerobic bacteria (TMAB) and total yeast and mold (TYM), but also decreased the relative activities of polyphenol oxidase (PPO) and lipoxygenase (LOX) by more than 91% after 90 s of treatment. HHAIB altered the cellular structure of celery stalks, shortened the drying time by 29.33-41.43%, and improved their hydration properties. HHAIB pretreatment promoted the conversion of bound phenolics to free phenolics in celery stalks, with significant increases in the contents of p-coumaric acid, apigenin, graveobioside A, and other components. The total free phenolic content increased by 56.99%, thus HHAIB enhanced the antioxidant activity. An electronic nose and sensory evaluation revealed that HHAIB-pretreated celery stalks better retained the characteristic herbal and pungent notes. GC-MS results indicated that HHAIB treatment optimized the aroma profile by regulating the contents and composition of terpenes, aldehydes, ketones, alcohols, and aromatic compounds.

Apium

Active Site Assembly by SMG5 as a Mechanism for SMG6 Endonuclease Licencing in Nonsense-mediated mRNA Decay.

Nonsense-mediated mRNA decay (NMD) is a conserved eukaryotic surveillance pathway that eliminates transcripts containing premature termination codons (PTCs). Substantial progress has been made in defining the transcript features that mark aberrant translation termination for NMD activation, yet key mechanistic steps remain incompletely understood - including how recruitment of the central NMD factor UPF1 is coupled to the downstream effector phase in which targeted mRNAs are nucleolytically degraded. In metazoans, NMD employs an endonucleolytic route mediated by SMG6, a PIN-domain nuclease, alongside SMG5 and SMG7, which act downstream of PTC recognition. SMG5 has recently been proposed to licence SMG6 activity, yet the molecular basis of this licencing has remained elusive. Here, we combine AlphaFold structural predictions with biochemical assays to investigate interactions among human SMG5, SMG6, and SMG7. Structural models predict a high-confidence interface between SMG5 and SMG6 PIN domains that forms a composite active site: a conserved SMG5 aspartate (D893) complements the SMG6 acidic triad to reinstate the canonical tetrad required for PIN-domain catalysis. In vitro, SMG6 alone exhibits weak endonucleolytic activity, which is enhanced ∼10-fold by the SMG5 PIN domain. Mutational analyses confirm that conserved residues from both proteins are essential for this composite configuration. Our findings reveal that the SMG5 PIN domain, previously considered catalytically inert, plays a critical role in activating SMG6 by completing its active site. This work provides mechanistic insight into the SMG5-dependent licencing step and uncovers a composite PIN nuclease architecture at the heart of the metazoan NMD effector phase.

Nonsense Mediated mRNA Decay

Distinct molecular responses to acute cold exposure revealed by comparative transcriptomic and metabolomic profiling in the bay scallop Argopecten irradians.

Acute cold stress can elicit distinct molecular responses even when bay scallop populations show similar phenotypic outcomes. We compared a seventh-generation fast-growing bay scallop line (BS) with a commercial control population (CC) during a 72-h acute cold exposure at -1 ± 0.3 °C. RNA-seq was used as the discovery layer, representative BS cold-responsive genes were evaluated by qRT-PCR, and paired LC-MS profiles provided a comparative metabolic layer. At baseline, 138 genes differed between BS and CC; after cold exposure, 134 of these baseline differences disappeared and 61 of 65 cold-state differences newly emerged. BS showed a larger transcriptomic response magnitude than CC, with 1129 cold-responsive genes compared with 28 genes in CC, and this ordering remained robust across multiple sensitivity analyses. Survival after 72 h was identical in BS and CC (83/90, 92.2% in each population). Biochemical responses were time-dependent and marker-specific: CAT, LZM, T-SOD and T-AOC showed population-by-time interactions, whereas GSH-Px and MDA did not, and the 72-h differences were not consistently favourable to BS. Metabolomic cold effects were strongly concordant between populations, and no feature showed a significant population-by-cold interaction. Features putatively assigned to arachidonic acid metabolism were enriched, but this provider-annotated pathway signal remains exploratory because authentic-standard confirmation was not performed. These findings indicate population-specific differences in molecular responsiveness but do not establish superior cold tolerance in BS.

Animals

In situ product monitoring in heterogeneous reaction of gaseous trimethylamine on Fe2O3/Fe(NO3)3: Effect of environmental factor and particle property.

Gas-particle reactions represent an important atmospheric heterogeneous transformation process for organic amines (OAs). Environmental factors and particle properties may impact the gas-particle reaction products. Although the products from gas-particle reactions can be monitored by various in situ techniques, related data remain scarce. Here, the interfacial and gaseous products from the reaction of trimethylamine on Fe2O3/Fe(NO3)3 particles under light irradiation with mixed NO2, O2, SO2 and H2O were monitored using in-situ diffuse reflectance Fourier transform infrared spectroscopy and proton transfer reaction time-of-flight mass spectrometry. Dark reaction of gaseous trimethylamine on Fe2O3/Fe(NO3)3 generated two interfacial products types: N-containing ones (CH3NCH2, CH3NO2, (CH3)2NCHO, and CH3N(OH)CHO) and N-free ones (alcohols, aldehydes and acids), both accumulating with reaction progression. Light irradiation and O2 oxidation enhanced formation of these products, while NO2 promoted the production of CH3NO2 and (CH3)2NCHO. H2O and SO2 occupied the active sites of particles to inhibit the formation of all products. Compared to Fe(NO3)3, Fe2O3 showed absolute dominance in contribution to the formation of products. Considering the smaller particle size of Fe2O3 and excess Fe(NO3)3, the physical mixing of them reduced the generation of interfacial products. Furthermore, gaseous products of CH3OH, HCHO, CH3CHO, HCOOH and CH3COOH detection clarified the N-free interfacial products. The presence of Fe(NO3)3 inhibited the formation of HCOOH and favored the formation of CH3CHO in the gas phase. By combining product information with thermodynamic calculations, the heterogeneous reaction pathways of trimethylamine were tentatively proposed. These findings provide a guiding significance for the migration of OAs in real atmospheric environment.

Methylamines

Simultaneous determination of imiquimod and terbinafine in skin permeation studies: Validation of a liquid chromatography method with fluorescence detection.

Chromoblastomycosis is a chronic, neglected subcutaneous mycosis posing significant therapeutic challenges. A topical strategy combining terbinafine (TBF), an antifungal, with imiquimod (IMQ), a TLR-7/8 agonist immunomodulator, has emerged a promising alternative. However, no validated analytical method is currently available to simultaneously quantify both drugs in skin, which is crucial for novel formulation development. This study reports the development and validation of a simple HPLC method with fluorescence detection (excitation 236 nm, emission 340 nm) for the simultaneous determination of TBF and IMQ extracted from porcine skin. Separation was achieved on a C8 reversed-phase column (125 × 4.0 mm, 5 μm) using a mobile phase of methanol and water (60,40, v/v), both containing 0.1% formic acid at a flow rate of 0.8 mL/min. The method showed excellent linearity (r > 0.999) over 0.01-1.0 μg/mL for IMQ and 0.1-2.0 μg/mL for TBF. Intra- and inter-day precision demonstrated coefficients of variation below 5%, and recovery rates from skin (79-105%) confirmed accuracy. Limits of detection were 0.001 μg/mL for IMQ and 0.004 μg/mL for TBF, with quantification limits of 0.02 μg/mL and 0.16 μg/mL, respectively. This selective, sensitive, and reproducible method represents a valuable analytical tool for supporting the development and quality control of topical formulations for chromoblastomycosis and other fungal skin diseases.

Animals

Illicium verum polysaccharide targets fimbriae and flagella to disrupt biofilm and inhibit multidrug-resistant Escherichia coli proliferation.

The widespread dissemination of multidrug-resistant (MDR) E. coli has led to a decrease in the efficacy of antibiotics, posing severe challenges to clinical anti-infective therapy. Owing to their safety, multitarget activities, and low risk of inducing drug resistance, plant polysaccharides represent a promising alternative strategy. In this study, an acidic polysaccharide (IVP-3) was isolated and purified from the medicinal and edible plant Illicium verum, and it was found to inhibit MDR E. coli colonization by disrupting its biofilm. The Mw of IVP-3 was determined to be 35.566 kDa. Its backbone consists of →4)-α-D-GalpA-6-OMe-(1→, →4)-α-D-GalpA-(1→, →4)-β-D-Galp-(1→, and →3,4)-α-D-GalpA-(1 → residues, whereas the branched chain is composed of α-L-Araf-(1 → 5)-α-L-Araf-(1 → attached to the O-5 position of →2,5)-α-L-Araf-(1→, which is further linked to the O-3 position of the backbone. Mechanistically, IVP-3 disrupts the structure of fimbriae and flagella, inhibits bacterial motility, effectively prevents initial biofilm adhesion, and eradicates preformed mature biofilms. Additionally, IVP-3 damages cell membrane integrity, disrupts the proton motive force, and induces energy metabolism disorder, efflux pump inhibition, and oxidative stress, ultimately leading to bacterial lysis. This study provides a theoretical basis for the development of natural antibacterial agents targeting MDR E. coli biofilms and for the high-value utilization of Illicium verum.

Biofilms

Determination of 13 per- and polyfluoroalkyl substances in human plasma samples using LC-MS/MS: application to capillary microsamples.

Per- and polyfluoroalkyl substances (PFAS) are chemicals widely applied in industrial processes and highly persistent in the environment, whose extensive use has been linked to adverse health effects. Venous plasma is the conventional matrix for PFAS assessment in blood, and LC-MS/MS is the most used quantification technique. Despite the relevance of this topic, biomonitoring data on human exposure to PFAS in Brazil remain limited. This study validated an LC-MS/MS method for determination of 13 PFAS in human plasma. Blood samples were collected from volunteers by phlebotomy, followed by protein precipitation with acetonitrile containing 1% formic acid (v/v) and solid-phase extraction. Chromatographic separation was achieved on an Acquity UPLC HSS T3 column. The assay was linear over a calibration range of 0.2-20 ng/mL. Intra- and inter-assay precision (CV%) were within the ranges of 2.06-12.0% and 0.25-10.7%, respectively. As for accuracy, results were 89.0-112.9%. Matrix effect ranged from -1.31 to 0.05%. Stability after four freeze/thaw cycles and under autosampler conditions were also confirmed for all analytes. The method was applied to 40 paired venous and capillary plasma samples. Both measures exhibited high correlation (r = 0.926). PFOS was the only compound detected at concentrations ≥0.2 ng/mL (LLOQ) in all samples, with capillary plasma concentrations of 0.85-13.50 ng/mL. In summary, the method showed good validation performance and demonstrated the suitability of capillary plasma samples as an alternative matrix for PFAS quantification.

Humans

Efficacy of NAs in combination with Peg-IFN for functional cure in patients with CHB: a meta-analysis of RCTs.

BACKGROUND: The goal of treating chronic hepatitis B (CHB) is to achieve functional cure. We aimed to evaluate the efficacy of the combination of nucleoside (acid) analogues (NAs) and pegylated interferon (Peg-IFN) on the functional cure of CHB patients at the EOT and at the EOF. METHOD: PubMed, Embase, and Web of Science were searched systematically up to March 15, 2025. Sixteen RCTs on CHB patients receiving combination or monotherapy were included. RESULT: Compared with NAs treatment, the NAs combined with Peg-IFN treatment group significantly improved HBsAg clearance rate (RR: 14.05, 95% CI 6.13-32.20) and HBsAg seroconversion rate (RR: 12.82, 95% CI 5.08-32.33) at the EOT. Moreover, compared with NAs treatment, the NAs combined with Peg-IFN treatment group significantly improved HBsAg clearance rate (RR: 7.70, 95% CI 4.24-13.98), HBsAg seroconversion rate (RR: 11.93, 95% CI 5.14-27.67) at the EOF. However, compared with Peg-IFN monotherapy, the combination therapy group did not show any improvement in HBsAg clearance rate, HBsAg seroconversion rate, and the rate of qHBsAg decrease > 1 log10 IU/mL at the EOT and the EOF. Moreover, in terms of safety, the Peg-IFN monotherapy group showed more ALT flares (ALT > 5 × ULN) during the treatment process. CONCLUSION: Compared with NAs therapy, Peg-IFN combined with NAs therapy significantly improves functional cure rate. However, combination therapy shows no additional advantage over Peg-IFN monotherapy in achieving functional cure. The Peg-IFN monotherapy group has a higher incidence of ALT flares than the combination therapy group.

Humans

Early hepatic protein responses to dietary restriction-refeeding in Japanese quail: A proteomic investigation.

Feed intake and refeeding after nutrient scarcity induce rapid metabolic adaptations in the poultry liver; however, hepatic proteomic recovery pathways in the early hours post-refeeding remain poorly defined. This study aimed to characterize early liver protein signatures in Japanese quail (Coturnix japonica) recovering from nutritional stress under two refeeding conditions. Eighteen 12-week-old male quails (245.20 ± 0.213 g) were assigned to three groups (n = 6): control fed ad libitum (12.13 MJ/kg), 24 h feed deprivation followed by 6 h refeeding, and 24 h low metabolizable energy (6.30 MJ/kg) diet followed by 6 h refeeding. In total, 854 proteins were identified, of which 515 met the filtering criteria. The low metabolizable energy refeeding showed higher abundance of proteins linked to ATP binding and carbohydrate/carboxylic acid metabolism, alongside detoxification-related proteins, while suppressing translation/RNA-binding machinery and antioxidant pathways. Feed-deprived refeeding enriched in oxidative phosphorylation and mitochondrial complex I assembly with reduced cytoplasmic translation, NMD-related components, and sulfur compound metabolism. A direct comparison indicated divergent recovery strategies: low metabolizable energy refeeding mainly reflected oxidoreductase activity and translation initiation, whereas feed-deprived refeeding potentially enriched mitochondrial ATP production and glutathione-based defenses. Our analysis indicate that 6 h of refeeding initiates an early, incomplete recovery toward hepatic homeostasis, with the severity of prior nutritional restriction dictating distinct liver metabolic priorities. Collectively, these findings might provide a preliminary understanding of the hepatic mechanisms involved in recovery from nutrient deprivation and may help in the development of feeding strategies for managing metabolic recovery in poultry. However, these findings should be considered hypothesis-generating pending further validation.

Animals

Prevention of postpartum methamphetamine use with micronized progesterone trial (PROMPT): A pilot randomized controlled trial.

OBJECTIVES: Methamphetamine use disorder (MUD) contributes to postpartum morbidity and mortality. Postpartum progesterone decline may destabilize γ-aminobutyric acid pathways, increasing craving and return to use. We assessed the feasibility and safety of micronized progesterone, generating efficacy estimates for preventing postpartum methamphetamine use. METHODS: We conducted a double-blind, randomized, placebo-controlled feasibility trial (November 2021-January 2024) at an academic center with a perinatal addiction clinic. Participants ≤ 12 weeks postpartum with ≥ 4 weeks of abstinence were randomized 1:1, stratified by opioid use disorder (OUD), to micronized progesterone 400mg (200mg twice daily) or identical placebo for 12 weeks. The primary outcome was feasibility, defined as achieving ≥ 80% of planned enrollment. Safety outcomes included adverse events (AEs) and serious adverse events (SAEs). Efficacy outcomes were return to methamphetamine use (weekly self-report and every two weeks urine toxicology) and methamphetamine craving. Analyses included intent-to-treat and per-protocol approaches, with loss to follow-up imputed as return to use. Craving trajectories were modeled using adjusted regression with interaction terms for medication for OUD (MOUD). RESULTS: Of 253 screened individuals, 43 were eligible and 34 were enrolled (91.8%; 18 progesterone, 16 placebo). Retention at 12 weeks was 88%. AE frequency was similar between groups (78% vs 81%; p > 0.05), and no maternal SAEs occurred. Four infant SAEs were deemed unrelated to treatment. Return to methamphetamine use did not differ between groups. Craving trajectories differed by MOUD type. CONCLUSIONS: Micronized progesterone was feasible and safe for postpartum individuals with MUD. MOUD-specific craving effects support evaluation in larger, multicenter efficacy trials. GOV REGISTRATION NUMBER: NCT05128071 NCT REGISTRATION: Prevention of postpartum methamphetamine use with micronized progesterone trial https://clinicaltrials.gov/study/NCT05128071.

Humans

Safety and outcomes of dapagliflozin initiation in critically ill patients with acute kidney injury: A post-hoc analysis of the defender trial.

BACKGROUND: SGLT2 inhibitor use in acute kidney injury (AKI) is controversial due to concerns about hemodynamic instability. We evaluated dapagliflozin initiation in critically ill patients with AKI enrolled in the DEFENDER trial. METHODS: Among 212 patients with AKI at enrollment (100 dapagliflozin, 112 control), we compared 28-day mortality, kidney replacement therapy (KRT), and composite death/KRT. Adjusted risk differences were estimated controlling for age, sepsis, baseline vasopressor use, and creatinine. Physiological trajectories (creatinine, urine output, fluid balance, acid-base parameters) over days 1-5 were analyzed using mixed models. Likelihood ratios quantified compatibility with clinically meaningful harm or benefit. RESULTS: Event rates were similar: 28-day mortality 38% vs 40%, KRT 12% vs 18%, composite 41% vs 42% (dapagliflozin vs control). Adjusted risk differences were - 1.9% (95% CI -14.5 to 10.7) for death, -7.4% (-16.2 to 1.5) for KRT, and - 0.9% (-13.6 to 11.8) for the composite. Physiological trajectories showed no divergence suggestive of hemodynamic or metabolic instability. Likelihood ratios provided limited separation: at 5% absolute effect threshold, LR against harm was 1.47 and against benefit 1.19. CONCLUSIONS: Dapagliflozin initiation in critically ill patients with AKI was not associated with excess mortality, KRT, or physiological derangement. The near-neutral evidential profile indicates neither moderate harm nor benefit can be excluded, supporting feasibility of dedicated trials of SGLT2 inhibitors in AKI.

Humans

Efficacy and Safety of the Dual Glucagon-Like Peptide-1 and Glucagon Receptor Agonist Mazdutide in Predominantly Chinese Adults With Obesity and/or Type 2 Diabetes: A Systematic Review and Meta-Analysis.

AIM: To assess the effects of mazdutide on body weight, HbA1c, metabolic outcomes, and adverse events in adults with overweight/obesity and/or type 2 diabetes (T2D). METHODS: This systematic review and meta-analysis included randomized controlled trials (RCTs) comparing mazdutide with placebo or active comparators in adults with overweight/obesity and/or T2D, identified through PubMed, Scopus, Web of Science, and ClinicalTrials.gov to 20 February 2026. Co-primary outcomes were percent change in body weight and change in HbA1c. Secondary outcomes included other weight-related and metabolic outcomes, as well as safety. Random-effects models were used to generate pooled mean differences (MDs) or risk ratios with 95% confidence intervals, and the certainty of the evidence (COE) was assessed using GRADE. RESULTS: Nine RCTs (N = 2292; most with low risk of bias) were included. In overweight/obesity without diabetes, mazdutide 3, 4, and 6 mg reduced body weight more than placebo (MDs -6.56%, -9.92%, and -11.1%, respectively; very low COE due to substantial heterogeneity and few trials). In T2D, mazdutide 4 and 6 mg reduced body weight and HbA1c versus placebo (moderate COE) and also outperformed dulaglutide for both outcomes. Mazdutide also improved waist circumference, lipids, liver enzymes, and uric acid levels. Gastrointestinal adverse events were more frequent, but serious adverse events and treatment discontinuation rates were comparable with those of the comparators. CONCLUSIONS: Mazdutide was associated with dose-dependent reductions in body weight and HbA1c, with broader metabolic benefits in predominantly Chinese adults with obesity and/or T2D. Longer-term, multi-ethnic studies are needed to confirm durability, generalizability, and cardiovascular safety.

Humans

Genomic and food-safety evaluation of Staphylococcus chromogenes in Chinese dairy milk.

Non-aureus staphylococci and mammaliicocci (NASM) cause mastitis and may contaminate milk and dairy products. Milk samples (n&#xa0;=&#xa0;1916) from cows with subclinical or clinical mastitis (SCM and CM, respectively) were collected from 28 large-scale (> 500 lactating cows) Chinese dairy farms. Overall, 999 NASM isolates representing 19 species were identified by MALDI-TOF MS and cpn60 sequencing, with Staphylococcuschromogenes, Mammaliicoccus sciuri and Staphylococcus haemolyticus being most prevalent. Antimicrobial resistance (AMR) was determined with disc diffusion; non-susceptible to penicillin was most common (SCM, 30% and CM, 29%) whereas cefoxitin non-susceptible NASM accounted for 8-10% of isolates; among these, 12.5% carried mecA but none carried mecC. Galleria mellonella was used to assess virulence of 78 strains of S. chromogenes, a dominant species; subsequently, 32 strains, representing higher- and lower-virulence in the Galleria model, were selected for whole-genome sequencing and comparative genomics. S. chromogenes isolates from CM had higher virulence (p&#xa0;<&#xa0;0.05) than those from SCM. The 32 genomes comprised 20 sequence types, indicating high genetic diversity. No robust genomic marker of Galleria virulence phenotype was identified in this selected WGS subset. Acquired resistance genes (n&#xa0;=&#xa0;5) were detected, including a first report of fusC in S. chromogenes; the fusC-positive isolate had an elevated fusidic acid MIC (8&#xa0;mg/L). Although S. chromogenes persisted in milk at 4&#xa0;&#xb0;C, pasteurization (64&#xa0;&#xb0;C for 30&#xa0;min) reduced viable counts to below detection. This study provided new insights into the prevalence, AMR, genomic diversity, and dairy-chain relevance of milk-derived NASM, particularly S. chromogenes. However, the genomic findings were based on an intentionally selected WGS subset and should be interpreted as hypothesis-generating rather than population-representative.

Animals

Nutrikinetics and bioavailability of Promunel&#xae;, a standardized poplar-type propolis phenolic extract: a double-blinded, placebo-controlled, cross-over, randomized trial.

Brown poplar-type propolis has been recognized and used for centuries to help prevent upper respiratory tract infections (URTIs). However, the scarce, incomplete information in humans on the nutrikinetics and bioavailability of its phenolic constituents, combined with a lack of standardization in its phenolic content and profile pose major challenges to develop bioactive ingredients. Thus, the aim of this study was to establish the nutrikinetics and total bioavailability (NKBA) parameters of brown poplar-type propolis phenolics in humans using the Standardized Propolis Extract (SPE) Promunel&#xae;. To achieve this, a 48 h NBKA study was conducted following a double blinded, randomized, placebo-controlled, cross-over design in healthy humans (n = 10) with two doses of SPE (1X = 400 mg or 4X = 1600 mg). Phenolic compounds were detected, identified and quantified in the extract, plasma and urine through different LC-MS/UV technologies. The SPE used is a rich (304.44 &#xb1; 15.61 &#xb5;mol mg-1) and diverse source of phenolic compounds (5 sub-families). A total of 63 and 85 phenolic metabolites were identified and quantified in plasma and urine, mostly in the form of glucuronides and sulfates. In plasma, phenolic metabolites reached Cmax (1.22 &#xb1; 0.20 for 1X and 4.80 &#xb1; 0.48 &#xb5;M for 4X) after 1 h of SPE intake, while urinary excretion occurred mostly during the first 3 h after. The total net bioavailability of SPE phenolic compounds at 48 h was 57.16 &#xb1; 5.71% for 1X and 43.82 &#xb1; 6.77% for 4X. Generally, the data between SPE 1X and 4X were proportional, indicating that a higher dose does not substantially modulate total net bioavailability. Overall, our data shows that brown poplar-type SPE phenolic compounds are highly bioavailable in the form of cinnamic acid and flavonoid conjugates, and that these compounds are rapidly absorbed and eliminated through the urine. Our results suggest that, for a sustained presence in circulation, brown poplar-type propolis supplements should be consumed more than once a day.

Humans

Addressing lignin composition and content via Arabidopsis arogenate dehydratase knockout and over-expression genotypes.

Following the down-selection of 14 Arabidopsis thaliana arogenate dehydratase (ADT) knockout and over-expression (OE) genotypes, the most highly contrasting quadruple knockout adt3/4/5/6 and ADT OE genotypes were subjected to proteomics, metabolomics, and scanning electron microscopy (SEM) analyses as needed, with results compared to Columbia wild-type (WT). The basal adt3/4/5/6 stem cross-sections, &#x223c;70% lignin content reduced, exhibited buckled vessel cell walls and partially detached xylary fibers, in contrast to WT and ADT4m/5&#x202f;m OE genotypes that did not. Anatomical defects primarily resulted from guaiacyl lignin level reductions in vessels with concomitant increased stem syringyl:guaiacyl (S/G) ratios. Phenylpropanoid and various upstream shikimate-chorismate pathway enzyme abundances, as well as specific monolignol oxidases (laccases/peroxidases), generally increased in adt3/4/5/6&#x202f;at different stem and rosette leaf growth/development stages, relative to WT. Opposite effects were largely observed with the ADT5m OE genotype. By contrast, flavonoid and glucosinolate pathway enzyme amounts varied. Such enzyme abundance increases were overall unproductive as adt3/4/5/6 was unable to restore WT, ADT4 OE, ADT5 OE, ADT5m OE, and ADT4m/5&#x202f;m OE secondary metabolite (lignin, phenylpropanoid, lignan, flavonoid, phenolic acid, and glucosinolate) levels. Conversely, ADT OE genotypes did not significantly increase programmed lignin levels or alter S/G compositions. In sum, proteomics analyses of adt3/4/5/6 and adt5 'perceived' that lignin and low molecular weight secondary metabolite amounts were not at 'programmed' levels as for WT and ADT OE genotypes but observed increases in relevant pathway protein abundances were futile. Notably though, proteomics analyses did not lead to predicting that lignin and associated biochemical pathways would have reduced metabolite levels, relative to WT and ADT OE genotypes. Genotype adt3/4/5/6, possibly the highest lignin level reduced genotype reported, did not utilize other phenolics to compensate. By contrast, the differential temporal and spatial deposition of cell wall oxidases again indicate the exquisite control over lignin deposition, and our lack of knowledge of precise lignin structure and assembly in subcellular regions of the lignified cell walls.

Lignin

Epilepsy Is Part of the CNS Phenotype in Classic Infantile Pompe Disease.

BACKGROUND AND OBJECTIVES: Enzyme replacement therapy has not only significantly improved motor outcome and survival in patients with classic infantile Pompe disease, but also revealed previously unrecognized central nervous system (CNS) involvement. In this international study, involving patients from the Netherlands, Italy, Argentina, Germany, the United Kingdom, and Taiwan, we investigated whether epilepsy should be considered part of the CNS phenotype. METHODS: We included patients with classic infantile Pompe disease, defined by the presence of hypertrophic cardiomyopathy, symptom onset < 6 months of age, complete acid &#x3b1;-glucosidase (GAA) deficiency, and/or 2 severe variants in the GAA gene, who developed epilepsy. Data on epilepsy characteristics, electroencephalogram (EEG), cognitive testing, serum neurofilament light chain (NfL), and brain magnetic resonance imaging (MRI) were retrospectively collected. RESULTS: Seventeen patients from 10 centers were identified. The median follow-up duration was 13.7 years (range 3.3-19). Seven patients had deceased at the time of analysis. The median age at first seizure was 11.5 years (range 2.5-17.5). Seizure semiology was variable: six patients experienced generalized tonic-clonic seizures and 3 focal seizures with impaired consciousness only; 6 had multiple seizure types, and 7 experienced seizures during fever or infection. Seizure frequency varied considerably (in 9 occasionally, 5 monthly, 2 weekly, 1 daily). The most common EEG findings were a slowed background activity and focal epileptiform discharges, not substantially activated by sleep. Levetiracetam was most frequently used as antiseizure medication. Overall, 70% of patients became seizure-free. Serum NfL was elevated in all 6 patients in whom it was measured, and 8 of 10 patients had an intelligence quotient &#x2264;66 at onset of epilepsy. Although brain MRI was not always performed at the age of first seizure, 14 of 15 patients showed white matter abnormalities, which were extensive in 11 of 14 (score &#x2265;7/12). Brain atrophy was present in 9 cases and calcifications in 4. DISCUSSION: Our findings suggest a potential increased frequency of seizures in classic infantile Pompe disease in comparison with unaffected children, occurring predominantly after the age of 7, and that epilepsy is part of the CNS phenotype. The risk of seizures should be evaluated during follow-up in long-term survivors with classic infantile Pompe disease.

Journal Article

Probiotic-derived extracellular vesicles as food-based nanocarriers: Mechanisms, functional applications, and future perspectives in food systems.

Probiotic-derived extracellular vesicles (PDEVs) are a promising type of postbiotic nanoparticle derived by fermentation of probiotics, and have gained growing interest as a potential application in food science and nutrition. These are lipid bilayer vesicles of nanoscale, which are naturally released by probiotic cells and contain a wide variety of bioactive molecules, such as proteins, nucleic acids, and metabolites. Moreover, PDEVs are highly stable, biocompatible, and can be easily engineered to have surfaces with high functionality, which makes them good candidates in functional engineering. In contrast to traditional live probiotics, PDEVs overcome the difficulties of preserving microbial viability during processing and storage, thus providing superior safety, stability, and predictable biological performance. This is a systematic review of the various functions of PDEVs in food systems. We conclude on the processes through which PDEVs control intestinal barrier integrity, alter gut microbiota composition, and alter host immune responses, and their potential to enhance gut health when added to functional foods. In addition to their health-promoting effects, PDEVs have shown significant potential as natural antimicrobial agents to preserve food and as effective nanocarriers of hydrophobic bioactive compounds, including fucoxanthin, to improve their stability, bioavailability, and targeted delivery. Moreover, PDEVs can be used as new regulators of microbial fermentation. However, it should be noted that a lot of the evidence that is available is still preliminary and the effectiveness of these applications in real food-processing and storage conditions has not been fully proven. Although they have potential, there are a number of challenges that still hinder the widespread use of PDEVs in the food industry. These involve the creation of scalable and cost-effective production processes, batch-to-batch consistency, vesicle stability in a variety of food matrices, and regulatory and safety considerations. Other emerging engineering approaches, such as surface functionalization and cargo loading, are also discussed in this review and could further increase the specificity, functionality, and application versatility of PDEVs in food systems. Moving forward, the incorporation of PDEVs into the next generation functional foods, novel food preservation methods, and customized nutrition plans should be prioritized in future studies. Further developments in these fields can make PDEVs useful platforms at the interface of food microbiology, nanotechnology, and human health.

Probiotics

A dual-dimensional CRISPR toolkit enables one-step high-efficiency multiplex genome editing in Komagataella phaffii.

Against the backdrop of green biomanufacturing, engineering methanol-utilizing Komagataella phaffii (K. phaffii) represents an effective strategy to expand the one carbon (C1) product profile and speed up the industrialization of C1-based bioeconomy. To address the technical challenges of low efficiency and cumbersome experimental procedures for multiplex gene editing and precise large-fragment integration during the reconstruction of complex metabolic pathways in K. phaffii, this study established a CRISPR toolkit - Efficient Multi-Gene Editing System 3.0 (EMGES 3.0) - which enabled one-step large-fragment integration coupled with multiplex gene knockout. EMGES 3.0 was constructed through the synergistic optimization of a repair-engineered chassis and an episomal CRISPR vector. For chassis engineering, five DNA repair modules: &#x394;lig4 (DNA Ligase IV, non-homologous end joining end ligation), ppMRE11(The endogenous MRE11 gene from Pichia pastoris) overexpression (The Meiotic Recombination 11, DNA double-strand break end resection), &#x394;rad9 (Radiation-Sensitive 9, DNA damage checkpoint regulation), &#x394;mph1 (Mutator Phenotype Helicase 1, improvement of homologous recombinant strand extension), and PapRecT-PaSSB co-expression (stabilization of recombination intermediates) were integrated to generate the highly recombinogenic strain Y09. For vector engineering, cenARS was replaced by panARS and the endogenous promoter PGAP was employed to drive the double hammerhead ribozyme-single guide RNA-hepatitis delta virus ribozyme (double HH-sgRNA-HDV: dHgH)-mediated sgRNA expression, yielding the optimized vector Nov_pGAP_panARS_pLAT1_Cas9. These two features on K. phaffii together enhanced the EMGES 3.0 to a higher standard of transformation rate and editing efficiency. According to our results, EMGES 3.0 achieved dual-functional gene knockout efficiencies between 76.6% and 100%. For insertion of medium-long fragments (>4.5&#x202f;kb), the efficiency achieved 93.3%. In addition, the one-step integration of ultra-long fragments (>16&#x202f;kb) achieved 14.8%, which was reported for the first time. Furthermore, the efficiency of simultaneous long-fragment integration at three neutral loci reached 38.4% (>15&#x202f;kb). We applied the system for one-step production of free fatty acids (FFAs, yield: 5.82 &#x223c; 7.30&#x202f;mg/L/OD600) and resveratrol (yield: 1.14 &#x223c; 1.28&#x202f;mg/L) using methanol as the sole carbon source. EMGES 3.0 provides a robust technical foundation for complex compounds biosynthesis and high-yield industrial strains, while also advancing K. phaffii as an industrial synthetic biology chassis for efficient C1 utilization.

CRISPR-Cas Systems