Ag-modified enhance the performances of ZnO@CFs based omnidirectional photoelectrochemical ultraviolet detectors.

There are several prospective applications for omnidirectional ultraviolet (UV) detectors and underwater detection detectors in optical systems and optical fields. In this work, ZnO nanorods arrays were grown on carbon fibers (CFs). An appropriate amount of Ag nanoparticles (NPs) was deposited on the surface of ZnO nanorods by photochemical deposition. This improved the performance of photoelectrochemical (PEC) based UV detectors. Under 365 nm and 10 mW cm-2 UV irradiation, the photocurrent density of the 30s-Ag/ZnO@CFs based PEC UV detector can reach 1.28 mA cm-2, which is about 7 times that of the ZnO@CFs based PEC UV detector, and the rising time is shortened from 0.17 s to 0.10 s. The reason is that increased absorption of ultraviolet light induced by the localized surface plasmon resonance. In addition, the detector exhibits a good flexibility and remains flexible after hundreds of bends and twists. Moreover, the detector is responsive in the range of rotation angle from 0 to 360°. It provides an insight to improve the photoelectric performance and underwater omnidirectional detection ability of the PEC UV detector.

Bio-nanoparticles loaded with synovial-derived exosomes ameliorate osteoarthritis progression by modifying the oxidative microenvironment.

BACKGROUND AND AIMS: Osteoarthritis (OA) is a prevalent degenerative joint disorder, marked by the progressive degeneration of joint cartilage, synovial inflammation, and subchondral bone hyperplasia. The synovial tissue plays a pivotal role in cartilage regulation. Exosomes (EXOs), small membrane-bound vesicles released by cells into the extracellular space, are crucial in mediating intercellular communication and facilitating the exchange of information between tissues. Our study aimed to devise a hydrogel microsphere infused with SOD3-enriched exosomes (S-EXOs) to protect cartilage and introduce a novel, effective approach for OA treatment. MATERIALS AND METHODS: We analyzed single-cell sequencing data from 4247 cells obtained from the GEO database. Techniques such as PCR, Western Blot, immunofluorescence (IF), and assays to measure oxidative stress levels were employed to validate the cartilage-protective properties of the identified key protein, SOD3. In vivo, OA mice received intra-articular injections of S-EXOs bearing hydrogel microspheres, and the effectiveness was assessed using safranine O (S.O) staining and IF. RESULTS: Single-cell sequencing data analysis suggested that the synovium influences cartilage via the exocrine release of SOD3. Our findings revealed that purified S-EXOs enhanced antioxidant capacity of chondrocytes, and maintained extracellular matrix metabolism stability. The S-EXO group showed a significant reduction in mitoROS and ROS levels by 164.2% (P < 0.0001) and 142.7% (P < 0.0001), respectively, compared to the IL-1ß group. Furthermore, the S-EXO group exhibited increased COL II and ACAN levels, with increments of 2.1-fold (P < 0.0001) and 3.1-fold (P < 0.0001), respectively, over the IL-1ß group. Additionally, the S-EXO group showed a decrease in MMP13 and ADAMTS5 protein expression by 42.3% (P < 0.0001) and 44.4% (P < 0.0001), respectively. It was found that S-EXO-containing hydrogel microspheres could effectively deliver SOD3 to cartilage and significantly mitigate OA progression. The OARSI score in the S-EXO microsphere group markedly decreased (P < 0.0001) compared to the OA group. CONCLUSION: The study demonstrated that the S-EXOs secreted by synovial fibroblasts exert a protective effect on chondrocytes, and microspheres laden with S-EXOs offer a promising therapeutic alternative for OA treatment.

p-Toluenesulfonic Acid Modified Two-Dimensional ZrSe2 as a Hole Transport Layer for High-Performance Organic Solar Cells.

Two-dimensional (2D) materials have attracted attention due to their excellent optoelectronic properties, but their applications are limited by their defects and vacancies. Surface modification is an effective method to restore their performance. Here, ZrSe2 is modified with conductive polymer p-toluenesulfonic acid (PTSA). It is found that PTSA can obtain electrons of ZrSe2 through the combination of -SO3H and ZrSe2, thus forming interfacial dipoles, which improve the work function of ZrSe2. In addition, -OH in PTSA can effectively fill the Se vacancy in ZrSe2 to form P-type doping, thereby improving its conductivity. ZrSe2 modified by the PTSA material is first used as a hole transport layer (HTL) in organic solar cells (OSCs). The efficiency of OSCs based on the PBDB-T:ITIC and PM6:L8-BO binary active layer with ZrSe2:PTSA as the novel HTL reaches 10.66 and 18.14%, which are obviously higher than the efficiency of OSCs with pure ZrSe2 as the HTL (8.48 and 15.64%). More interestingly, the stability of the device with ZrSe2:PTSA as HTL is significantly better than that of PEDOT:PSS. This study shows that the modification of the organic material can effectively improve the photoelectric performance of ZrSe2 and explores the physical mechanism of the interaction between the organic modifier and 2D materials.

Continuous selenite biotransformation and biofuel production by marine diatom in the presence of fulvic acid.

In this study, the biochemical response of Phaeodactylum tricornutum to varying concentrations of inorganic selenium (Se) was investigated. It was observed that, when combined with fulvic acid, P. tricornutum exhibited enhanced uptake and biotransformation of inorganic Se, as well as increased microalgal lipid biosynthesis. Notably, when subjected to moderate (5 and 10 mg/L) and high (20 and 40 mg/L) concentrations of selenite under fulvic acid treatment, there was a discernible redirection of carbon flux towards lipogenesis and protein biosynthesis from carbohydrates. In addition, the key parameters of microalgae-based biofuels aligned with the necessary criteria outlined in biofuel regulations. Furthermore, the Se removal capabilities of P. tricornutum, assisted by fulvic acid, were coupled with the accumulation of substantial amounts of organic Se, specifically SeCys. These findings present a viable and successful approach to establish a microalgae-based system for Se uptake and biotransformation.

Zinc-energized dynamic hydrogel accelerates bone regeneration via potentiating the coupling of angiogenesis and osteogenesis.

Insufficient initial vascularization plays a pivotal role in the ineffectiveness of bone biomaterials for treating bone defects. Consequently, enhancing the angiogenic properties of bone repair biomaterials holds immense importance in augmenting the efficacy of bone regeneration. In this context, we have successfully engineered a composite hydrogel capable of promoting vascularization in the process of bone regeneration. To achieve this, the researchers first prepared an aminated bioactive glass containing zinc ions (AZnBg), and hyaluronic acid contains aldehyde groups (HA-CHO). The composite hydrogel was formed by combining AZnBg with gelatin methacryloyl (GelMA) and HA-CHO through Schiff base bonding. This composite hydrogel has good biocompatibility. In addition, the composite hydrogel exhibited significant osteoinductive activity, promoting the activity of ALP, the formation of calcium nodules, and the expression of osteogenic genes. Notably, the hydrogel also promoted umbilical vein endothelial cell migration as well as tube formation by releasing zinc ions. The results of in vivo study demonstrated that implantation of the composite hydrogel in the bone defect of the distal femur of rats could effectively stimulate bone generation and the development of new blood vessels, thus accelerating the bone healing process. In conclusion, the combining zinc-containing bioactive glass with hydrogels can effectively promote bone growth and angiogenesis, making it a viable option for the repair of critical-sized bone defects.

Knowledge, attitudes, and practices among Chinese reproductive-age women toward uterine adenomyosis.

Objective: This study aimed to assess the knowledge, attitudes and practices (KAP) among Chinese reproductive-age women toward uterine adenomyosis. Methods: This web-based cross-sectional study was conducted between April 2023 and September 2023 at the Second Hospital of Hebei Medical University. A self-designed questionnaire was developed to collect demographic information of reproductive-age women, and assess their KAP toward uterine adenomyosis. Results: A total of 520 valid questionnaires were collected. Among the participants, 127 (24.42%) were diagnosed with uterine adenomyosis, and 120 (23.08%) were accompanied by uterine fibroids. The mean knowledge, attitudes and practices scores were 3.54 ± 3.72 (possible range:0-10), 20.96 ± 3.19 (possible range:5-25) and 24.01 ± 4.95 (possible range:7-35), respectively. The structural equation model demonstrated that knowledge had direct effects on attitudes and practices, as indicated by a path coefficient of 0.714 (p < 0.001) and 1.510 (p < 0.001), respectively. Moreover, attitudes had direct effects on practices, with a path coefficient of 0.226 (p = 0.001). Conclusion: The findings revealed that reproductive-age women have insufficient knowledge, negative attitudes, and poor practices toward the uterine adenomyosis. Comprehensive training programs are needed to improve reproductive-age women practices in this area.

Exposure to microplastics renders immunity of the thick-shell mussel more vulnerable to diarrhetic shellfish toxin-producing harmful algae.

Despite both microplastics (MPs) and harmful algae blooms (HABs) may pose a severe threat to the immunity of marine bivalves, the toxification mechanism underlying is far from being fully understood. In addition, owing to the prevalence and sudden occurrence characteristics of MPs and HABs, respectively, bivalves with MP-exposure experience may face acute challenge of harmful algae under realistic scenarios. However, little is known about the impacts and underlying mechanisms of MP-exposure experience on the susceptibility of immunity to HABs in bivalve mollusks. Taking polystyrene MPs and diarrhetic shellfish toxin-producing Prorocentrum lima as representatives, the impacts of MP-exposure on immunity vulnerability to HABs were investigated in the thick-shell mussel, Mytilus coruscus. Our results revealed evident immunotoxicity of MPs and P. lima to the mussel, as evidenced by significantly impaired total count, phagocytic activity, and cell viability of haemocytes, which may result from the induction of oxidative stress, aggravation of haemocyte apoptosis, and shortage in cellular energy supply. Moreover, marked disruptions of immunity, antioxidant system, apoptosis regulation, and metabolism upon MPs and P. lima exposure were illustrated by gene expression and comparative metabolomic analyses. Furthermore, the mussels that experienced MP-exposure were shown to be more vulnerable to P. lima, indicated by greater degree of deleterious effects on abovementioned parameters detected. In general, our findings emphasize the threat of MPs and HABs to bivalve species, which deserves close attention and more investigation.

Photochemical transformation and immobilization of thallium in the presence of iron and arsenic: Mechanistic insights from the coupled formation of arsenate complexes.

Despite the occurrence of thallium (Tl) in the acidic mining-affected areas being highly positively correlated with iron (Fe) and arsenic (As), the effects of the two accompanying elements on Tl redox transformation and immobilization remain largely unknown. Here, we investigated the photochemical redox kinetics and immobilization efficiency of Tl for a wide range of As/Fe and As/Tl ratios under acidic conditions. We provided the first experimental confirmation of the complexation of Tl(III) with As(V) by the spectrophotometric method and revealed the role of Tl(III)-As(V) complexes in decreasing the photoreduction rate of Tl(III) under sunlight. Additionally, the negative impact of colloidal Fe(III)-As(V) and Fe(III)-As(III) complexes formation on decreasing photoactive Fe(III) speciation and thus the apparent quantum yield of •OH was highlighted, which consequently hindered the oxidative conversion of Tl(I) to Tl(III). We rationalize the kinetics results by developing the model which quantitatively describes the photochemistry of Tl. Furthermore, we demonstrated the colloid-facilitated immobilization of Tl(III) through the formation of Tl(III)-As(V) clusters and surface adsorption onto the complexes. This study broadens the mechanistic understanding of redox transformation and immobilization potential of Tl and aids in assessing Tl speciation as well as its coupled transformation with Fe and As species in the sunlit water environment.

Enantioselective sulfonylation to construct 3-sulfonylated oxindoles.

Asymmetric synthesis of 3-sulfonylated 3-substituted oxindoles through the addition of sodium sulfinate salts to 3-bromo-3-substituted oxindoles has been achieved using chiral nickel complexes of N,N'-dioxides. This method facilitates the creation of diverse chiral sulfonyl oxindoles, several of which display promising anticancer properties. Notably, the catalyst demonstrates remarkable tolerance to water, crucial for maintaining enantioselectivity. Furthermore, the utilization of topographic steric maps of the catalysts offers valuable insights into the mechanism underlying enantioselection reversal.

Cascaded controlled delivering growth factors to build vascularized and osteogenic microenvironment for bone regeneration.

The process of bone regeneration is intricately regulated by various cytokines at distinct stages. The establishment of early and efficient vascularization, along with the maintenance of a sustained osteoinductive microenvironment, plays a crucial role in the successful utilization of bone repair materials. This study aimed to develop a composite hydrogel that would facilitate the creation of an osteogenic microenvironment for bone repair. This was achieved by incorporating an early rapid release of VEGF and a sustained slow release of BMP-2. Herein, the Schiff base was formed between VEGF and the composite hydrogel, and VEGF could be rapidly released to promote vascularization in response to the early acidic bone injury microenvironment. Furthermore, the encapsulation of BMP-2 within mesoporous silica nanoparticles enabled a controlled and sustained release, thereby facilitating the process of bone repair. Our developed composite hydrogel released more than 80% of VEGF and BMP-2 in the acidic medium, which was significantly higher than that in the neutral medium (about 60%). Moreover, the composite hydrogel demonstrated a significant improvement in the migratory capacity and tube formation ability of human umbilical vein endothelial cells (HUVECs). Furthermore, the composite hydrogel exhibited an augmented ability for osteogenesis, as confirmed by the utilization of ALP staining, alizarin red staining, and the upregulation of osteogenesis-related genes. Notably, the composite hydrogel displayed substantial osteoinductive properties, compared with other groups, the skull defect in the composite hydrogels combined with BMP-2 and VEGF was full of new bone, basically completely repaired, and the BV/TV value was greater than 80%. The outcomes of animal experiments demonstrated that the composite hydrogel effectively promoted bone regeneration in cranial defects of rats by leveraging the synergistic effect of an early rapid release of VEGF and a sustained slow release of BMP-2, thereby facilitating vascularized bone regeneration. In conclusion, our composite hydrogel has demonstrated promising potential for vascularized bone repair through the enhancement of angiogenesis and osteogenic microenvironment.

Activation of NRF2 by celastrol increases antioxidant functions and prevents the progression of osteoarthritis in mice.

Excessive oxidative stress impairs cartilage matrix metabolism balance, significantly contributing to osteoarthritis (OA) development. Celastrol (CSL), a drug derived from Tripterygium wilfordii, has recognized applications in the treatment of cancer and immune system disorders, yet its antioxidative stress mechanisms in OA remain underexplored. This study aimed to substantiate CSL's chondroprotective effects and unravel its underlying mechanisms. We investigated CSL's impact on chondrocytes under both normal and inflammatory conditions. In vitro, CSL mitigated interleukin (IL)-1ß-induced activation of proteinases and promoted cartilage extracellular matrix (ECM) synthesis. In vivo, intra-articular injection of CSL ameliorated cartilage degeneration and mitigated subchondral bone lesions in OA mice. Mechanistically, it was found that inhibiting nuclear factor erythroid 2-related factor 2 (NRF2) abrogated CSL-mediated antioxidative functions and exacerbated the progression of OA. This study is the first to elucidate the role of CSL in the treatment of OA through the activation of NRF2, offering a novel therapeutic avenue for arthritis therapy.

The Relationship between Childhood Abuse and Suicidal Ideation among Chinese College Students: The Mediating Role of Core Self-Evaluation and Negative Emotions.

Childhood abuse is a significant risk factor for suicidal ideation. However, the underlying mediation mechanism necessitates further exploration. This study investigated the mediating role of core self-evaluation and negative emotions in the relationship between childhood abuse and suicide ideation in young adults. A sample of 3103 college students from 11 universities across 8 provinces in China was analyzed. Childhood abuse, core self-evaluation, negative emotions, and suicidal ideation were assessed using the Childhood Trauma Questionnaire (CTQ-CF), Core Self-Evaluation Scale, Affect Scale, and Beck Suicidal Ideation Scale (BSI-CV), respectively. Data analysis was conducted using SPSS 19.0 and SPSS Macro Process. We found that high scores for childhood abuse were associated with elevated levels of suicidal ideation, whereas low scores for core self-evaluation were closely linked to heightened levels of negative emotions and suicidal ideation. Furthermore, core self-evaluation and negative emotions mediated the relationship between childhood abuse and suicidal ideation through three significant paths. The results demonstrate that childhood abuse can directly impact suicidal ideation in young adulthood and indirectly influence suicidal ideation by affecting core self-evaluation and negative emotions. They suggest that addressing core self-evaluation and negative emotions in individuals who have experienced childhood abuse may help prevent or treat suicidal ideation.

Toroidal micelles formed in viscoelastic aqueous solutions of a double-tailed surfactant with two quaternary ammonium head groups.

Innovation in surfactant structures is an effective way to prepare new soft materials with novel applications. In this study, we synthesized a double-tailed surfactant containing two quaternary ammonium head groups (Di-C12-N2). The Di-C12-N2 solution behavior was investigated by surface tension, fluorescence, rheology, and cryo-TEM methods. Although Di-C12-N2 contained a large double-tailed hydrophobic group, the solubility of Di-C12-N2 was ∼90 mmol L-1 at 25 °C with a Krafft temperature of ∼1 °C. The increase in Di-C12-N2 concentration in the solutions led to the formation of various aggregates, including spherical micelles, worm-like micelles, multi-layered vesicles, and a rare type of small toroidal micelles. The two quaternary ammonium head groups in Di-C12-N2 led to strong electrostatic interactions between molecules, which was critical for the formation of toroidal micelles. Moreover, with an added NaCl concentration of 40 mmol L-1, the viscosity of the 5 mmol L-1Di-C12-N2 solution increased by ∼1000 times compared to the pure 5 mmol L-1Di-C12-N2 solution, revealing the high sensitivity of the unique head groups to ionic strength. This study enriches the research on the self-assembly principles of surfactants and brings new potential applications for new soft materials.

Wormlike micellar solutions formed by an anionic surfactant and a cationic surfactant with two head groups.

Innovation in the molecular structure of surfactants is important for the preparation of soft materials with novel properties. In this study, we synthesized a cationic surfactant, N1,N1,N1,N1,N3,N3,N3-pentamethyl-N3-(3-stearamidopropyl)propane-1,3-diammonium bromide, hereafter referred to as C18-DQA. Unlike conventional cationic surfactants, C18-DQA contains two quaternary ammonium head groups and a long-saturated alkyl chain equal to a chain length of 21 carbon atoms. C18-DQA exhibits a low Krafft point of ∼0 °C and a water solubility >1000 mM at 25 °C. The critical micelle concentration (cmc) of C18-DQA was determined to be 0.59 mM using the Nile red method. C18-DQA was mixed with sodium laurate (SL) at different molar ratios to produce transparent solutions with excellent viscoelasticity over a wide concentration range. The 1 : 1.5 molar ratio C18-DQA/SL mixed solutions exhibited gel-like behavior for a total surfactant concentration of 2.88 wt% (75 mM). The solution with a total surfactant concentration of 300 mM (120 mM C18-DQA and 180 mM SL) achieved a maximum zero-shear viscosity (η0) of 4224 Pa s. Cryogenic transmission electron microscopy analysis revealed the formation of extremely long wormlike micelles, with a cross-sectional diameter of 5 nm and contour length >3 µm, in the mixed solutions. C18-DQA and SL molecules were drawn close by electrostatic attractions, leading to a suitable molecular geometry for the extensive growth of wormlike micelles. This work will act as an important reference for the future preparation of highly viscoelastic solutions by mixing cationic and anionic surfactants. The proposed system is also expected to have potential applications in cosmetic formulations, home care products, and oilfield fracturing fluids.

Identification and prediction of molecular subtypes of atherosclerosis based on m6A immune cell infiltration.

BACKGROUND: Atherosclerosis is a complex disease with multiple molecular subtypes that are not yet fully understood. Recent studies have suggested that N6-methyladenosine (m6A) alterations may play a role in the pathogenesis of atherosclerosis. However, the relationship between m6A regulators and atherosclerosis remains unclear. METHODS: In this study, we analyzed the expression levels of 25 m6A regulators in a cohort of atherosclerosis (AS) and non-AS patients using the R "limma" package. We also used machine learning models, including random forest (RF), support vector machine (SVM), generalized linear model (GLM), and extreme gradient boosting (XGB), to predict the molecular subtypes of atherosclerosis based on m6A immune cell infiltration. RESULTS: We found that METTL3, YTHDF2, IGFBP1, and IGF2BP1 were overexpressed in AS patients compared to non-AS patients, while the other significant m6A regulators showed no significant difference. Our machine learning models achieved high accuracy in predicting the molecular subtypes of atherosclerosis based on m6A immune cell infiltration. CONCLUSION: Our study suggests that m6A alterations may play a role in the pathogenesis of atherosclerosis, and that machine learning models can be used to predict molecular subtypes of atherosclerosis based on m6A immune cell infiltration. These findings may have important implications for the detection and management of atherosclerosis.

Knockout of the sugar transporter OsSTP15 enhances grain yield by improving tiller number due to increased sugar content in the shoot base of rice (Oryza sativa L.).

Sugar transporter proteins (STPs) play critical roles in regulating plant stress tolerance, growth, and development. However, the role of STPs in regulating crop yield is poorly understood. This study elucidates the mechanism by which knockout of the sugar transporter OsSTP15 enhances grain yield via increasing the tiller number in rice. We found that OsSTP15 is specifically expressed in the shoot base and vascular bundle sheath of seedlings and encodes a plasma membrane-localized high-affinity glucose efflux transporter. OsSTP15 knockout enhanced sucrose and trehalose-6-phosphate (Tre6P) synthesis in leaves and improved sucrose transport to the shoot base by inducing the expression of sucrose transporters. Higher glucose, sucrose, and Tre6P contents were observed at the shoot base of stp15 plants. Transcriptome and metabolome analyses of the shoot base demonstrated that OsSTP15 knockout upregulated the expression of cytokinin (CK) synthesis- and signaling pathway-related genes and increased CK levels. These findings suggest that OsSTP15 knockout represses glucose export from the cytoplasm and simultaneously enhances sugar transport from source leaves to the shoot base by promoting the synthesis of sucrose and Tre6P in leaves. Subsequent accumulation of glucose, sucrose, and Tre6P in the shoot base promotes tillering by stimulating the CK signaling pathway.

Mechanistic insights into the effects of diuron exposure on Alexandrium pacificum.

Diuron (N-(3,4-dichlorophenyl)-N,N­dimethylurea, DCMU), a ureic herbicide, is extensively used in agriculture to boost crop productivity; however, its extensive application culminates in notable environmental pollution, especially in aquatic habitats. Therefore, the present study investigated the effect of diuron on the dinoflagellate Alexandrium pacificum, which is known to induce harmful algal blooms (HAB), and its potential to biodegrade DCMU. Following a four-day DCMU exposure, our results revealed that A. pacificum proficiently assimilated DCMU at concentrations of 0.05 mg/L and 0.1 mg/L in seawater, attaining a complete reduction (100 % efficiency) after 96 h for both concentrations. Moreover, evaluations of paralytic shellfish toxins content indicated that cells subjected to higher DCMU concentrations (0.1 mg/L) exhibited reductions of 73.4 %, 86.7 %, and 75 % in GTX1, GTX4, and NEO, respectively. Exposure to DCMU led to a notable decrease in A. pacificum's photosynthetic efficacy, accompanied by increased levels of reactive oxygen species (ROS) and suppressed cell growth, with a growth inhibition rate of 41.1 % at 72 h. Proteomic investigations pinpointed the diminished expression levels of specific proteins like SxtV and SxtW, linked to paralytic shellfish toxins (PSTs) synthesis, as well as key proteins associated with Photosystem II, namely PsbA, PsbD, PsbO, and PsbU. Conversely, proteins central to the cysteine biosynthesis pathways exhibited enhanced expression. In summary, our results preliminarily resolved the molecular mechanisms underlying the response of A. pacificum to DCMU and revealed that DCMU affected the synthesis of PSTs. Meanwhile, our data suggested that A. pacificum has great potential in scavenging DCMU.

Transcriptional insights of citrus defense response against Diaporthe citri.

Citrus melanose, caused by Diaporthe citri, is one of the most important and widespread fungal diseases of citrus. Previous studies demonstrated that the citrus host was able to trigger the defense response to restrict the spread of D. citri. However, the molecular mechanism underlying this defense response has yet to be elucidated. Here, we used RNA-Seq to explore the gene expression pattern at the early (3 days post infection, dpi) and late (14 dpi) infection stages of citrus leaves in response to D. citri infection, and outlined the differences in transcriptional regulation associated with defense responses. The functional enrichment analysis indicated that the plant cell wall biogenesis was significantly induced at the early infection stage, while the callose deposition response was more active at the late infection stage. CYP83B1 genes of the cytochrome P450 family were extensively induced in the callus deposition-mediated defense response. Remarkably, the gene encoding pectin methylesterase showed the highest upregulation and was only found to be differentially expressed at the late infection stage. Genes involved in the synthesis and regulation of phytoalexin coumarin were effectively activated. F6'H1 and S8H, encoding key enzymes in the biosynthesis of coumarins and their derivatives, were more strongly expressed at the late infection stage than at the early infection stage. Collectively, our study profiled the response pattern of citrus leaves against D. citri infection and provided the transcriptional evidence to support the defense mechanism.

Trehalose-6-Phosphate Synthase Contributes to Rapid Cold Hardening in the Invasive Insect Lissorhoptrus oryzophilus (Coleoptera: Curculionidae) by Regulating Trehalose Metabolism.

Rapid cold hardening (RCH) is known to rapidly enhance the cold tolerance of insects. Trehalose has been demonstrated to be a cryoprotectant in Lissorhoptrus oryzophilus, an important invasive pest of rice in China. Trehalose synthesis mainly occurs through the Trehalose-6-phosphate synthase (TPS)/trehalose-6-phosphate phosphatase (TPP) pathway in insects. In this study, the TPS gene from L. oryzophilus (LoTPS) was cloned and characterized for the first time. Its expression and trehalose content changes elicited by RCH were investigated. Our results revealed that RCH not only increased the survival rate of adults but also upregulated the expression level of LoTPS and increased the trehalose content under low temperature. We hypothesized that upregulated LoTPS promoted trehalose synthesis and accumulation to protect adults from low-temperature damage. To further verify the function of the LoTPS gene, we employed RNA interference (RNAi) technology. Our findings showed that RCH efficiency disappeared and the survival rate did not increase when the adults were fed dsRNA of LoTPS. Additionally, inhibiting LoTPS expression resulted in no significant difference in trehalose content between the RCH and non-RCH treatments. Furthermore, the expression patterns of trehalose transporter (TRET) and trehalase (TRE) were also affected. Collectively, these results indicate the critical role of LoTPS in L. oryzophilus cold resistance after RCH induction. LoTPS can enhance survival ability by regulating trehalose metabolism. These findings contribute to further understanding the role of TPS in insect cold resistance and the invasiveness of L. oryzophilus. Moreover, RNAi of LoTPS opens up possibilities for novel control strategies against L. oryzophilus in the future.