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Phenotypic, physiological and transcriptomic analysis of graded salt stress responses in Pyrus betulifolia Bunge and functional characterization of the hub gene PbSTY46.

Pyrus betulifolia Bunge is a salt‑tolerant rootstock for pear, but its salt‑tolerance mechanisms remain largely unknown. In this study, P. betulifolia seedlings were subjected to graded NaCl stress at concentrations of 0 (CK), 50 (T1), 100 (T2), and 200 (T3) mM. We integrated phenotypic observation, physiological assessment, transcriptomic profiling, and functional gene validation to systematically elucidate its salt tolerance mechanisms. Salt stress inhibited seedling growth and root traits in a concentration-dependent manner, and T3 caused the most severe damage. Osmotic solutes responded differentially: soluble sugars peaked under T2, while proline peaked under T3. Antioxidant enzymes showed tissue-specific biphasic responses and declined after prolonged T3 stress. Meanwhile, chlorophyll and photosynthesis decreased, whereas anthocyanin increased, indicating a metabolic shift from photosynthesis to photoprotection. Transcriptome analysis revealed distinct responses depending on stress intensity: mild stress induced membrane lipid remodeling, moderate stress activated circadian rhythm and hormone signaling, and severe stress enhanced phenylpropanoid biosynthesis and thiamine metabolism. Gene Set Enrichment Analysis (GSEA) further highlighted progressive enrichment of phenylpropanoid biosynthesis, heme binding, and oxidoreductase activity. Weighted Gene Co‑expression Network Analysis (WGCNA) identified a blue module significantly positively correlated with root traits, from which the hub gene PbSTY46 was identified. Functional validation via overexpression, loss‑of‑function mutants, and pharmacological interventions (MeJA/DIECA) confirmed that PbSTY46 acts through JA signaling to enhance antioxidant enzyme activities and thereby confer salt tolerance. Collectively, P. betulifolia adopts a "survival‑first" strategy that coordinates growth arrest, osmotic homeostasis, and ROS scavenging. These findings establish PbSTY46 as a key regulator that links JA signaling to antioxidant defense. Thus, PbSTY46 represents a promising candidate for marker‑assisted breeding of salt‑tolerant pear cultivars.

Salt Stress

Variations in the viral hepatitis C prevalence and treatment status by material hardship and cumulative risk among people who inject drugs.

People who inject drugs (PWID) are disproportionately impacted by viral hepatitis C (HCV). Among PWID, homelessness, poverty, and material insecurity elevate infectious disease risk. We hypothesized a positive association between material hardship (difficulty accessing basic needs) and lifetime diagnosis of HCV, and a negative association between cumulative risk (material hardship and years since first injection) and HCV treatment. From 2021-22, we conducted a survey among community-recruited PWID that included items on HCV outcomes, material hardship (a sum score of usually (4) to never (1) having difficulty finding food, clothing, shelter, restrooms, and showers in the past 3 months), and years since injection drug use initiation. We developed a latent variable, cumulative risk, by combining individual scores of material hardship indicators and years since first injection drug use. Among our sample of PWID (n = 471), 246 (53%) participants reported lifetime HCV diagnosis and 27% of those who tested positive for HCV reported ever or current treatment (n = 67). In modified-Poisson regression, a one-unit increase in material hardship score was associated with a 3% (OR: 1.03, 95% CI: 1.01%, 1.05%) increase in odds of HCV diagnosis. In latent modeling, among PWID testing positive for HCV, a one-unit increase in cumulative risk score was associated with a 0.28 (OR: -0.28, 95% CI: -0.50, -0.06), decrease in the Z-score odds of receiving HCV treatment. Findings emphasize structural interventions to strengthen material security and co-delivering basic needs with health services to improve HCV-related outcomes among PWID.

HCV

Clinical performance of two lithium disilicate CAD/CAM materials in posterior Class II inlay restorations: A 48-month randomised split-mouth clinical trial.

OBJECTIVES: To compare the clinical performance of Amber Mill (AM) and IPS e.max CAD (EM) lithium disilicate computer-aided design/computer-aided manufacturing (CAD/CAM) materials in posterior Class II inlay restorations and characterise their baseline properties. METHODS: Thirty-four adults received paired AM and EM posterior Class II inlays (68 restorations) in a triple-blind randomised split-mouth trial followed for 48 months. Restorations were evaluated at baseline and annually using revised World Dental Federation (FDI) criteria, with fracture and retention as the primary endpoint. Baseline characterisation included flexural strength, shear bond strength, translucency parameter, and scanning electron microscopy. McNemar, Wilcoxon signed-rank, Friedman, one-way analysis of variance, Tukey post hoc, and inter-rater agreement analyses were used. RESULTS: At 48 months, 18 paired participants were available for primary analysis. Failures occurred in 2 of 18 AM restorations and in 3 of 18 EM restorations, corresponding to success rates of 88.9% and 83.3%, respectively, with no significant between-material difference (McNemar p = 1.000). No catastrophic bulk ceramic fracture was observed. Secondary FDI scores remained mostly within the clinically acceptable range; marginal staining deteriorated over time in both groups (p < .001) without significant between-material differences. Baseline material testing showed significant material- and translucency-dependent differences in flexural strength, shear bond strength, and translucency. CONCLUSIONS: Within the limitations of the 48-month follow-up and the tested Class II inlay indication, AM showed clinical performance comparable to EM. Observed clinical complications were related to retention or marginal/interface behaviour. CLINICAL SIGNIFICANCE: For posterior Class II lithium disilicate CAD/CAM inlays, medium-term complications were mainly retention/interface-related, suggesting adhesive-interface durability may be as important as baseline ceramic strength.

Humans

Self-healing materials for food packaging: Design principles, activation mechanisms and implications for food safety.

Self-healing materials (SHMs), originally developed to restore mechanical integrity, have recently attracted growing interest in food packaging. By autonomously repairing physical damage, SHMs help preserve packaging integrity, barrier performance, food safety, and shelf-life during storage and transportation. This review summarizes recent advances in the design principles, activation mechanisms, material systems and food packaging applications of SHMs. Key healing strategies, including microencapsulation, dynamic covalent bond exchange, reversible non-covalent interactions and responsiveness to external stimuli such as temperature, pH, and humidity, are discussed. Representative material systems, including biopolymer-based films, hydrogels, nanocomposites, and stimuli-responsive polymers are evaluated with respect to their relevance to packaging animal-derived foods, fruits, and vegetables. Performance evaluation methods, sustainability implications, and food-contact safety concerns are addressed. Despite promising healing efficiency and mechanical resilience, challenges remain regarding production cost, food-grade safety, migration risks, trigger compatibility and stability under fluctuating environmental conditions. Future research should focus on scalable manufacturing, standardized evaluation protocols, repeated damage-healing safety assessment, regulatory compliance, and integration with intelligent packaging technologies.

Food Packaging

Nephropathies Associated with Sickle Cell Trait and How to Study Them.

Sickle cell trait (SCT), which carries a single point mutation in the hemoglobin-&#x3b2; (HBB) gene, has long been considered a benign condition. However, epidemiological evidence challenges this assumption, revealing that individuals with SCT face an elevated risk of renal dysfunction. However, this field of study remains ill-defined as it has focused on sickle cell disease (SCD), where renal complications are severe. As SCT is more prevalent than SCD, consequences of nephropathies in this group translate into a substantial and largely unaddressed public health burden. Clinical data, primarily observational, implicate age and sex in the development of SCT-associated nephropathies. These manifestations span glomerular hyperfiltration, tubular damage, hematuria, renal papillary necrosis, renal medullary carcinoma, and progression to chronic kidney disease, all complications that cluster disproportionately in older male individuals. Despite this, the mechanistic basis of SCT nephropathy, the thresholds at which renal injury becomes clinically significant, and the optimal strategies for early identification and prevention remain inadequately defined. In vitro studies have primarily focused on SCD blood cell biology, with SCT receiving comparatively little attention. Humanized murine models (i.e., Berkeley and Townes) have recapitulated some SCT-associated renal phenotypes but need to be more fully characterized. This review aims to provide an overview of the biology of sickle cell trait nephropathies, the gaps in our knowledge, and the model systems we can use to fill those gaps.

Journal Article

Shielding performance and clinical applicability of lead-free materials in computed tomography.

Owing to the high radiation exposure associated with computed tomography (CT) examinations and the image quality degradation caused by conventional radiation shielding materials, this study evaluated the dose reduction performance and image quality maintenance potential of a newly developed lead-free composite shielding material. This material was composed of bismuth, tungsten, tungsten carbide, aluminium, and polyurethane. Phantom-based dose measurements demonstrated that the shielding material achieved dose reduction rates ranging from 17.6% to 37.6%, depending on tube voltage. Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and changes in tube current-time product (mAs) under a scout-based automatic exposure control (AEC) protocol were analysed according to the presence or absence of the shielding material across regions. For the clinical evaluation, CT scans were performed on four patients. Furthermore, the images were reviewed to evaluate whether this material affected image quality. The shielding material exhibited radiation reduction levels comparable to those reported in previous studies. SNR and CNR analyses showed minor statistical variations in certain regions; however, most differences were not statistically significant, and even significant differences remained within a range that did not compromise diagnostic image quality. Under the scout-based AEC protocol, the use of the shielding material resulted in less than 1% variation in mAs values. No visually perceptible artefacts or clinically significant image quality degradation were observed. The proposed composite shielding material demonstrated the potential to mitigate some limitations of conventional shielding materials and showed preliminary clinical feasibility as an adjunctive strategy for radiation dose reduction in CT examinations.

Radiation Protection

Choice of Anesthesia in Microelectrode Recording-guided Deep Brain Stimulation Surgery for Parkinson's Disease (CHAMPION): A Noninferiority Randomized Controlled Trial.

BACKGROUND: Deep brain stimulation for Parkinson's disease is often performed under conscious sedation or general anesthesia. However, anesthetic agents may influence intraoperative microelectrode recording, and the optimal anesthesia method for microelectrode recording remains unclear. This study compared general anesthesia and conscious sedation in preserving microelectrode recording signal intensity during deep brain stimulation. METHODS: In this prospective, noninferiority randomized controlled trial, patients with Parkinson's disease (United Kingdom Brain Bank criteria) undergoing elective bilateral surgery were randomized 1:1 to the conscious sedation or the general anesthesia group. During surgery, a desflurane anesthetic titrated against the quality of the electrophysiologic signal was applied in the general anesthesia group, whereas patients in the conscious sedation group received dexmedetomidine anesthesia. The primary outcome was the proportion of patients with high-quality microelectrode recording (normalized root mean square greater than 2.0), assessed postoperatively off-line. Secondary outcomes included operation and recording duration, 6-month clinical efficacy, and complication rates. RESULTS: Of 188 randomized patients (94 general anesthesia, 93 conscious sedation), desflurane anesthesia was noninferior for high normalized root mean square proportion (89.4% vs . 90.3%; difference, -0.96%; 95% CI, -9.62 to 7.70). The general anesthesia group had shorter operative time (difference, -9.07&#x2009;min; 95% CI, -13.99 to -4.14; P < 0.001). At 6 months, changes in Unified Parkinson's Disease Rating Scale score (difference, -2.50; 95% CI, -7.20 to 2.20; P = 0.297), levodopa equivalent daily dose (difference, -58.4&#x2009;mg; 95% CI, -133.56 to 16.75; P = 0.128), and complication rates (general anesthesia: 10.9% vs . conscious sedation: 8.9%; P = 0.655) were comparable between the groups. CONCLUSIONS: General anesthesia is noninferior to conscious sedation for microelectrode-guided subthalamic nucleus deep brain stimulation, providing equivalent signal intensity and clinical outcomes while improving procedural efficiency, supporting its use as a valid clinical option.

Humans

Challenges and future directions in AI-driven biomaterials for microbiome-associated oral infectious diseases: A systematic review.

Oral biofilm-induced antimicrobial resistance is the core pathogenic mechanism of microbiome-associated oral infectious diseases (dental caries, periodontitis, peri-implantitis, and endodontic infection). Traditional therapies and biomaterials are limited by poor biofilm penetration, drug resistance induction, single functionality, and inadequate adaptation to dynamic oral microenvironmental changes (e.g., pH fluctuations, salivary rinsing, masticatory stimulation). Artificial intelligence (AI) has transformed the field by integrating materials science, microbiology, and stomatology data. Via machine learning, deep learning, and multi-physics simulation, AI optimizes biomaterial physicochemical properties, decodes microenvironmental signals, constructs precise sensing-response loops, and supports the full chain of material design, performance prediction, and action simulation, advancing treatment from empirical intervention to precision regulation. This systematic review retrieved literature from PubMed, Embase, and Web of Science (January 2016-January 2026) using keywords across three dimensions: AI, biomaterials, and oral microbiome. Following inclusion/exclusion criteria, 99 articles were included. It elaborates on five core mechanisms of AI-driven oral biomaterials (precise oral microbiome analysis, targeted material design/optimization, performance prediction/simulation, targeted delivery/intervention, effect evaluation/dynamic regulation), analyzes their applications in microbiome-targeted biomaterial research and development (R&D) and clinical practice for the four major oral infectious diseases, addresses technical bottlenecks (insufficient targeting specificity and precision of biomaterials, poor stability and durability in complex oral microenvironments, inadequate biofilm disruption capacity, and clinical translation obstacles), and proposes future directions (multimodal design to enhance targeting specificity, structural and component optimization to improve stability/durability, development of multi-mechanism synergistic biofilm disruption strategies, strengthening translational research for clinical application, and deep integration of AI in the full chain of biomaterial R&D). This work provides comprehensive theoretical and practical support for the R&D, optimization, and clinical translation of AI-driven microbiome-targeted oral biomaterials.

Humans

Recent advances in electrode materials for electrochemical detection of zearalenone.

Zearalenone (ZEN) is an estrogenic mycotoxin commonly found in cereals, animal feed, and processed foods, making it an important concern for food safety and public health. Conventional chromatographic and immunological methods can detect ZEN; however, they often require expensive instruments, lengthy sample preparation, and skilled personnel, which restrict their use for rapid and on-site testing. Electrochemical sensors have attracted enormous interest of the scientific community because of their high sensitivity, rapid response, low cost, miniaturization potential, and compatibility with portable systems. The analytical performance of the electrochemical sensors is strongly influenced by electrode materials, morphology, conductivity, porosity, surface functionality, and the efficiency of bioreceptor immobilization. Despite several reviews on mycotoxin detection, a systematic assessment connecting electrode-material design, modification strategies, sensing mechanisms, and electroanalytical performance specifically for ZEN sensing remain limited. This review critically evaluates recent advances in metal oxides, carbon-based materials, metal-organic- and covalent organic frameworks, MXenes, polymers, and hybrid composites for electrochemical ZEN detection. Particular attention has been given to their roles in electron transfer, analyte enrichment, selectivity, and real-sample analysis. The review also compares the major limitations of current sensing systems, including complex fabrication, matrix interference, insufficient long-term stability, poor inter-electrode reproducibility, and limited scalability. Finally, future directions for developing robust, cost-effective, portable, and commercially viable ZEN sensors are discussed.

Journal Article

Ageing effects on chemical, physical, mechanical, and morphological properties of clear aligners - a systematic review.

BACKGROUND: Clear aligner (CA) therapy has experienced rapid use over the past two decades to treat orthodontic malocclusions. However, evidence on CA material degradation in the oral environment remains limited and often focuses on single brands or isolated material properties. OBJECTIVES: To investigate CA ageing characteristics across different materials and brands and evaluate the chemical, physical, mechanical, and morphological changes following simulated or intraoral ageing. SEARCH METHODS: Five databases (PubMed, Web of Science, MEDLINE [Ovid], ProQuest, and Scopus) were searched to 18 March 2026, with no restrictions. ELIGIBILITY CRITERIA: Studies assessing CA properties after intraoral use or simulated ageing (thermocycling, cyclic loading, or liquid immersion) were included. DATA COLLECTION AND ANALYSIS: Study selection followed PRISMA 2020. RoB was assessed using QUIN for purely in vitro studies, JBI for cohort in vivo studies, and Cochrane RoB 2 for RCTs. Results were synthesised narratively and organised by property domain, as substantial methodological heterogeneity precluded formal meta-analysis. Where protocols were comparable, a simple pooled weighted mean was calculated and presented graphically. RESULTS: Ninety-five studies were included. RoB was low in eight studies, moderate in sixty-two, and high in twenty-five. Chemical composition remained largely stable during ageing, though some brands showed trace elemental release. Physical, mechanical, and morphological properties showed material-dependent deterioration. Pooled discolouration was greatest with coffee (weighted mean &#x394;E&#x2009;=&#x2009;70.9), versus tea (&#x394;E&#x2009;=&#x2009;18.4) and red wine (&#x394;E&#x2009;=&#x2009;11.5), with Invisalign&#xae; consistently exceeding the clinically perceptible threshold. Force decay of 40-90% typically occurred within 48&#xa0;h. Thermoplastic polyurethane (TPU)-based and directly printed aligners (DPAs) generally showed greater susceptibility than polyethylene terephthalate glycol-modified (PETG)-based aligners, though findings on hardness, roughness, and stiffness were inconsistent. CONCLUSIONS: CA materials undergo clinically relevant degradation during use, particularly in TPU-based and DPAs aligners. Clinicians may need to prioritise material-specific protocols, reinforce dietary and cleaning instructions, and consider force decay when determining aligner replacement intervals. PROSPERO number: CRD420251110248.

Humans

From pathobiology to prescribing in obesity-driven HFpEF: A systematic review and practical therapeutic framework.

Heart failure with preserved ejection fraction (HFpEF) is increasingly driven by obesity and cardiometabolic dysfunction. In this phenotype, the dominant biology extends beyond congestion alone and includes visceral and epicardial adiposity, systemic inflammation, impaired myocardial energetics, endothelial dysfunction, and exertional elevation in filling pressures. We performed a PRISMA-compliant systematic review with structured narrative evidence synthesis to evaluate pharmacological therapy in obesity-driven HFpEF, searching PubMed/MEDLINE, Scopus, Web of Science Core Collection, ClinicalTrials.gov, and WHO ICTRP through December 2025. Eighteen reports were included in the final qualitative synthesis. The available evidence supports sodium-glucose cotransporter 2 inhibitors as the pharmacological foundation because they provide the most mature outcome data across the preserved ejection fraction spectrum. Semaglutide improves symptoms, physical limitations, exercise capacity, and body weight in dedicated obesity-related HFpEF trials, whereas tirzepatide extends this signal by improving clinical status and reducing worsening heart failure events. Finerenone broadens the therapeutic platform in HF with mildly reduced or preserved ejection fraction, although obesity-specific data remain indirect. Conventional neurohormonal therapies retain a selective role, but they are not the principal biological match for this phenotype. Obesity-driven HFpEF should therefore be managed as a cardiometabolic syndrome with heart failure expression, using a phenotype-based sequence that links diagnosis, decongestion, SGLT2 inhibition, obesity-directed therapy, and selective adjunctive intensification.

Humans

Longitudinal Relations among Perceived Economic Stress, Teacher-Student Relationships, and Cybervictimization: Exploring Within-Person Links.

Family economic hardship has been identified as a risk factor for adolescents' cybervictimization. Nevertheless, existing studies have primarily focused on objective economic conditions, and little is known about the within-person association between perceived economic stress and adolescents' cybervictimization and the mediating mechanisms underlying this association. To fill these gaps, the random intercept cross-lagged model was employed to examine the dynamic relations among perceived economic stress, teacher-student relationships, and cybervictimization. The data were obtained from a sample of 2407 Chinese adolescents (Mage = 12.75, SD = 0.58, 50.23% girls at baseline) recruited from seven schools and assessed at three time points over one year. At the between-person level, there were no significant associations among perceived economic stress, teacher-student relationships, and cybervictimization. At the within-person level, perceived economic stress positively predicted later cybervictimization over time, and this effect was unidirectional. The bidirectional relations between perceived economic stress and teacher-student relationships remained stable over time. Cybervictimization significantly and negatively predicted subsequent teacher-student relationships across time, indicating a unidirectional predictive effect. Additionally, perceived economic stress indirectly predicted cybervictimization through teacher-student relationships. The findings highlight the importance of distinguishing within-person from between-person processes and shed light on the longitudinal role of teacher-student relationships in the association between perceived economic stress and cybervictimization.

Humans

Access Block and Ambulance Ramping: The Canaries of the Healthcare System.

OBJECTIVE: To identify evidence-based factors leading to the global challenge of hospital access block and inform strategies to improve emergency access performance. METHODS: A mixed methods approach was followed comprising an umbrella review of published systematic reviews, qualitative analysis of the perspectives of patients and healthcare workers, and quantitative analysis of contextual factors and 6&#x2009;years of ambulance, emergency inpatient and ward movement records for the 25 largest public hospitals in Queensland, Australia. RESULTS: A key set of findings and recommendations were identified to improve emergency access that are practical and actionable. These comprise the introduction of inpatient discharge metrics and monitoring to shift focus from the front door of hospitals to the 'back door'; increasing support for primary care, community care, aged care, NDIS and vulnerable groups; maintaining demand-side strategies such as increasing inpatient-equivalent care alternatives (e.g., hospital in the home, acute care within nursing home services); investment in prehospital flow; improving hospital processes such as extended-hour discharge lounges; improving workforce; and revising funding policies. CONCLUSIONS: The study findings fill a gap in the evidence regarding challenges and recommendations for improving patient flow within hospital emergency departments and across the broader health system. Focussing efforts at the 'back end' of the inpatient journey is a critical step to improve emergency care outcomes.

Humans

Long-term efficacy of cognitive behavioural therapy for insomnia (CBT-I) on depressive symptoms: A systematic review and meta-analysis of randomised controlled trials.

Depressive symptoms are common in individuals with persistent insomnia. Previous meta-analyses of randomised controlled trials (RCTs) showed that cognitive behavioural therapy for insomnia (CBT-I) can reduce depressive symptoms at post-treatment. However, the long-term maintenance of these improvements has never been systematically examined. To fill-in this gap, we conducted a systematic review and meta-analysis of the long-term (&#x2265;3 months) effects of CBT-I on depressive symptoms. The review was registered in PROSPERO (CRD420251146061). Only RCTs in adults with insomnia were considered. Pubmed, Scopus, Psycinfo, CINAHL, and Medline were searched up to 12 September 2025 with no predefined time constraints. From 5359 records initially retrieved, we included 53 articles reporting on 13,608 individuals. After outliers removal, random effects meta-analysis showed that CBT-I was superior to control conditions in reducing depressive symptoms at 3 [k&#x202f;=&#x202f;29, d&#x202f;=&#x202f;-.35, [95% CI: -.49 to -.21], p&#x202f;<&#x202f;.001], 6 [k&#x202f;=&#x202f;29, d&#x202f;=&#x202f;-.32, [95% CI: -.59 to -.05], p&#x202f;=&#x202f;.018], and 12 [k&#x202f;=&#x202f;10, d&#x202f;=&#x202f;-.25, [95% CI: -.39 to -.12], p&#x202f;<&#x202f;.001] months follow-ups. Results demonstrate that the effects of CBT-I on depressive symptoms are sustained throughout the year following treatment, although effects may decline over time.

Humans

Fused Deposition Modeling (FDM) of polyether-ether-ketone (PEEK) dental implants: A systematic review of the effect of printing parameters on mechanical behaviour and surface quality.

PURPOSE: This systematic review evaluated how FDM printing parameters influence mechanical behaviour and surface characteristics of 3D-printed PEEK and identified parameter combinations linked to the most favourable mechanical performance and surface quality. MATERIALS AND METHODS: An electronic search was conducted in: MEDLINE (Ovid), PubMed, Embase, Web of Science, Scopus, and Compendex (last update: January 2025). Studies that evaluated the effect of FDM printing parameters on mechanical and surface properties of PEEK were included. Outcomes comprised compressive, tensile, and flexural strengths, elastic modulus, fracture toughness, surface hardness, roughness, and wettability. RESULTS: Of 4005 reports screened, 54 manuscripts were included. 92.6% (n&#x202f;=&#x202f;50) of articles showed low risk-of-bias, while 7.4% (n&#x202f;=&#x202f;4) showed medium risk-of-bias. Tensile strength was the most investigated mechanical parameter (78%), followed by elastic modulus (41%), flexural strength (30%), compressive strength (20%), and fracture toughness (6%). Surface roughness was the most evaluated surface property (30%), followed by hardness (17%) and wettability (6%). Across studies, higher printing temperatures, lower printing speed, thinner layer thickness, and maximum infill ratio in a horizontal printing orientation were associated with higher strengths, less warpage, increased accuracy, and improved surface quality. CONCLUSION: Specific combinations of FDM printing parameters can significantly improve the mechanical and surface properties of PEEK. However, it is difficult to meet all the optimal conditions simultaneously. Thus, balancing between different parameters must be considered in practical production.

Benzophenones

Transforming Curcuma longa leaf waste into cellulose scaffolds.

The constant dearth of transplantable tissues and organs in India required the development of substitute biomaterials for tissue engineering. Plant-based decellularized scaffolds have become attractive options because of their abundance, ethical acceptability, architectural diversity, and lower risks of zoonotic transmission. Curcuma longa leaves were investigated in this study as a possible source of cellulose-based scaffolding for use in biomedical applications. After cuticle removal, an immersion decellularization technique utilizing sodium dodecyl sulphate (SDS) and triton-X-100 was developed to successfully remove cellular and nuclear material while maintaining leaf parenchyma architecture. Histology, DAPI staining, scanning electron microscopy, and a notable decrease in leftover DNA content all demonstrated efficient decellularization. When contrasted with native leaves, the resultant decellularized C. longa leaf scaffolds showed significant increase in porosity, water vapor transmission rate and swelling percent, and significantly lower contact angle with an optimum surface roughness promoting cell adhesion. Mechanical test manifest higher tensile strength with decreased stiffness. Fourier transform infrared spectra of leaf scaffold reveals persistence of different components except cuticle but the intensity of different peaks was decreased. The leaf scaffolds showed superior hemocompatibility and excellent compatibility with Madin-Darby canine kidney cells (MDCK) which is demonstrated by cell attachment and proliferation. MTT assay of seeded scaffold showed significantly higher metabolically active cell. In vivo subcutaneous implantation of decellularized scaffolds showed host tissue incorporation, accumulation of collagen, and neovascularization. C. longa leaf scaffolds can be utilized as cost effective and sustainable biomaterials for soft tissue engineering and regenerative medicine.

Curcuma

Evolution of maize recombination landscape during domestication.

Despite the plethora of knowledge about the benefits of meiotic recombination and numerous theoretical studies examining how recombination rates evolve, there is a general lack of empirical support and consensus across species. To fill this knowledge gap, we characterized the evolution of recombination landscape in maize during its domestication from teosinte and related the observed changes to established theoretical frameworks. Through examining recombination in experimental populations of maize and teosinte and the population genomics approach of identifying historical recombination events using ancestral recombination graph inference to generate saturated maize and teosinte recombination maps, we found that during domestication, maize experienced a 12% increase in its genome-wide recombination rate. Furthermore, maize evolved higher recombination rates on the long arms of chromosomes in regions closer to centromeres, where recombination is generally very low. The repatterning of crossover events came from changes in global crossover positioning rather than alterations in cis-acting chromatin factors. Consequently, we found evidence of selection acting on trans-acting recombination modifiers affecting crossover interference and controlling the interference-dependent class I crossover pathway. We show that CO repatterning was likely beneficial for maize fitness, as significant recombination rate increases were predominantly in gene-rich regions, which harbor domestication-related variation. This work suggests genomic and mechanistic processes leading to the evolution of meiotic recombination landscape in response to directional selection pressure and provides evidence for the evolutionary advantage of recombination.

Zea mays

Preparation and study of non-thrombotic and biostable sulfobetaine-modified small-diameter polyurethane vascular grafts.

A novel sulfobetaine-modified polysiloxane-polycarbonate polyurethane (ZSiPCU) was synthesized. In vitro characterizations revealed that polysiloxane surface enrichment endowed the material with excellent biostability. Importantly, sulfobetaine zwitterions formed a robust hydration layer, effectively suppressing protein adsorption and platelet adhesion to ensure outstanding hemocompatibility. Furthermore, the material supported the adhesion and proliferation of vascular endothelial cells, confirming its cytocompatibility, while its elastomeric matrix provided rapid mechanical self-sealing capabilities. Electrospun ZSiPCU grafts were evaluated in a 3-month rat abdominal aorta model, maintaining high patency rates and facilitating in situ luminal endothelialization and smooth muscle cell remodeling. Additionally, superior puncture resistance of the grafts was demonstrated by puncture tests, with complete hemostasis achieved within 2&#x202f;mins through mechanical self-sealing.

Polyurethanes