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This study aimed to investigate the impact of varying the formulation of a specific peptide hydrogel (PepGel) on the release kinetics of rhBMP-2 in vitro. Three PepGel formulations were assessed: (1) 50% v/v (peptides volume/total volume) PepGel, where synthetic peptides were mixed with crosslinking reagents and rhBMP-2 solution; (2) 67% v/v PepGel; (3) 80% v/v PepGel. Each sample was loaded with 12 µg of rhBMP-2 and incubated in PBS. Released rhBMP-2 was quantified by ELISA at 1 h, 6 h, and 1, 2, 4, 7, 10, 14, and 21 days. To explore how PepGel formulations influence rhBMP-2 release, the gel porosities, swelling ratios, and mechanical properties of the three PepGel formulations were quantitatively analyzed. The results showed that rhBMP-2 encapsulated with 50% v/v PepGel exhibited a sustained release over the 21-day experiment, while the 67% and 80% v/v PepGels demonstrated significantly lower rhBMP-2 release rates compared to the 50% formulation after day 7. Higher histological porosity of PepGel was significantly correlated with increased rhBMP-2 release rates. Conversely, the swelling ratio and elastic modulus of the 50% v/v PepGel were significantly lower than that of the 67% and 80% v/v formulations. In conclusion, this study indicates that varying the formulation of crosslinked PepGel can control rhBMP-2 release rates in vitro by modulating gel porosity, swelling ratio, and mechanical properties. Encapsulation with 50% v/v PepGel offers a sustained rhBMP-2 release pattern in vitro; if replicated in vivo, this could mitigate the adverse effects associated with burst release of rhBMP-2 in clinical applications. [ABSTRACT FROM AUTHOR]

HBP‐A is the main active component of a traditional Chinese medicine Huaizhen Yanggan Capsule, for the remarkable treatment of knee osteoarthritis (KOA). This study aimed to elucidate the ameliorative effect of HBP‐A on meniscus hypertrophy and mineralisation in KOA and the molecular mechanism of its action. An Hartley guinea pig model of KOA that underwent anterior cruciate ligament transection (ACLT) and a model of rat primary meniscus fibrochondrocytes (PMFs) were used to investigate the ameliorative effect of HBP‐A on meniscal hypertrophy and calcification and its signal transduction mechanism of action. The results show that Guinea pig's meniscus width, as well as the area of meniscus calcification and meniscus and articular cartilage injury score, were significantly reduced in the HBP‐A intervention group compared to the ACLT group. The expression levels of mtrix metalloproteinase 13 (MMP13), runt‐related transcription factor 2 (Runx2), Indian hedgehog (Ihh), alkaline phosphatase (ALP), and ankylosis homologue (ANKH) at the protein and gene level significantly decreased in the HBP‐A intervention group compared to the ACLT group. In vitro study, apoptosis, hypertrophy, and calcification of rat PMFs after 10% stretch force were significantly improved with HBP‐A intervention. Western blot and RT‐qPCR showed that hypertrophy, calcification, and p38 MAPK signalling pathway‐related markers of PMFs were incredibly depressed in the HBP‐A intervention group compared to the 10% stretch force group. In conclusion, HBP‐A can slow down meniscus hypertrophy and mineralisation induced by abnormal mechanical loading, and its mechanism of action may be through the p38‐MAPK signalling pathway. [ABSTRACT FROM AUTHOR]

SUMMARY: Drought stress impairs plant growth and poses a serious threat to maize (Zea mays) production and yield. Nevertheless, the elucidation of the molecular basis of drought resistance in maize is still uncertain. In this study, we identified ZmSCE1a, a SUMO E2‐conjugating enzyme, as a positive regulator of drought tolerance in maize. Molecular and biochemical assays indicated that E3 SUMO ligase ZmMMS21 acts together with ZmSCE1a to SUMOylate histone acetyltransferase complexes (ZmGCN5‐ZmADA2b). SUMOylation of ZmGCN5 enhances its stability through the 26S proteasome pathway. Furthermore, ZmGCN5‐overexpressing plants showed drought tolerance performance. It alleviated O2− accumulation, malondialdehyde content, and ion permeability. What's more, the transcripts of stress‐responsive genes and abscisic acid (ABA)‐dependent genes were also significantly upregulated in ZmGCN5‐overexpressing plants under drought stress. Overexpression of ZmGCN5 enhanced drought‐induced ABA production in seedlings. Taken together, our results indicate that ZmSCE1a enhances the stability of ZmGCN5, thereby alleviating drought‐induced oxidative damage and enhancing drought stress response in maize. Significance Statement: In this study, we revealed the regulatory mechanism of ZmSCE1a‐mediated SUMOylation of ZmGCN5 in response to drought stress. These findings expand the understanding of maize's response to drought stress and further increase crop yields under drought stress. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Previous studies have demonstrated linear polymers embedded with B←N units display efficient photocatalytic hydrogen evolution performance, but their limited structural tunability restricts photogenerated carrier dynamics modulation. Current researches mainly focus on linear polymers, while the study of B←N units in the field of two‐dimension conjugated polymers (2DCPs) photocatalytic hydrogen evolution remains an uncultivated ground. Herein, three 2DCPs containing B←N units were synthesized and their photocatalytic hydrogen production performance was investigated. Among them, the BN‐Tz exhibited the best property with a hydrogen production rate of 89.5 μmol·h–1, while BN‐Ph and BN‐TPB were only 26.4 and 8.5 μmol·h–1, respectively. Comprehensive analyses showed that the remarkable photocatalytic ability of BN‐Tz catalyst was mainly attributed to its superior transport and separation of photogenerated carriers, as well as the ability to construct a stronger built‐in electric field and better planarity. Meanwhile, it was found that the manipulation of the electronic properties of the structures connected to the B←N unit could effectively regulate the molecular polarity, thus achieving the control of the electronic structure of the materials. This work extends the application of materials containing B←N units in photocatalysis and lays a good foundation for the subsequent design of photocatalysts containing B←N units. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Previous studies have demonstrated linear polymers embedded with B←N units display efficient photocatalytic hydrogen evolution performance, but their limited structural tunability restricts photogenerated carrier dynamics modulation. Current researches mainly focus on linear polymers, while the study of B←N units in the field of two‐dimension conjugated polymers (2DCPs) photocatalytic hydrogen evolution remains an uncultivated ground. Herein, three 2DCPs containing B←N units were synthesized and their photocatalytic hydrogen production performance was investigated. Among them, the BN‐Tz exhibited the best property with a hydrogen production rate of 89.5 μmol·h–1, while BN‐Ph and BN‐TPB were only 26.4 and 8.5 μmol·h–1, respectively. Comprehensive analyses showed that the remarkable photocatalytic ability of BN‐Tz catalyst was mainly attributed to its superior transport and separation of photogenerated carriers, as well as the ability to construct a stronger built‐in electric field and better planarity. Meanwhile, it was found that the manipulation of the electronic properties of the structures connected to the B←N unit could effectively regulate the molecular polarity, thus achieving the control of the electronic structure of the materials. This work extends the application of materials containing B←N units in photocatalysis and lays a good foundation for the subsequent design of photocatalysts containing B←N units. [ABSTRACT FROM AUTHOR]

We examined the degree to which content of states' writing standards and assessments (using measures of content range, frequency, balance, and cognitive complexity) and their alignment were related to student writing achievement on the 2007 National Assessment of Educational Progress (NAEP), while controlling for student, school, and state characteristics. We found student demographic characteristics had the largest effect on between-state differences in writing performance, followed by state policy-related variables, then state and school covariates. States with writing tests that exhibited greater alignment with the NAEP writing assessment demonstrated significantly higher writing scores. We discuss plausible implications of these findings.

Plant growth exhibits rhythmic characteristics, and gibberellins (GAs) are involved in regulating cell growth, but it is still unclear how GAs crosstalk with circadian rhythm to regulate cell elongation. The study analyzed growth characteristics of wild-type (WT), zmga3ox and zmga3ox with GA3 seedlings. We integrated metabolomes and transcriptomes to study the interaction between GAs and circadian rhythm in mediating leaf elongation. The rates of leaf growth were higher in WT than zmga3ox, and zmga3ox cell length was shorter when proliferated in darkness than light, and GA3 restored zmga3ox leaf growth. The differentially expressed genes (DEGs) between WT and zmga3ox were mainly enriched in hormone signaling and cell wall synthesis, while DEGs in zmga3ox were restored to WT by GA3. Moreover, the number of circadian DEGs that reached the peak expression in darkness was more than light, and the upregulated circadian DEGs were mainly enriched in cell wall synthesis. The differentially accumulated metabolites (DAMs) were mainly attributed to flavonoids and phenolic acid. Twenty-two DAMs showed rhythmic accumulation, especially enriched in lignin synthesis. The circadian DEGs ZmMYBr41/87 and ZmHB34/70 were identified as regulators of ZmHCT8 and ZmBM1, which were enzymes in lignin synthesis. Furthermore, GAs regulated ZmMYBr41/87 and ZmHB34/70 to modulate lignin biosynthesis for mediating leaf rhythmic growth. [ABSTRACT FROM AUTHOR]