The GRAS protein OsDLA involves in brassinosteroid signalling and positively regulates blast resistance by forming a module with GSK2 and OsWRKY53 in rice.

Brassinosteroids (BRs) play a crucial role in shaping the architecture of rice (Oryza sativa) plants. However, the regulatory mechanism of BR signalling in rice immunity remains largely unexplored. Here we identify a rice mutant dla, which exhibits decreased leaf angles and is insensitive to 24-epiBL (a highly active synthetic BR), resembling the BR-deficient phenotype. The dla mutation caused by a T-DNA insertion in the OsDLA gene leads to downregulation of the causative gene. The OsDLA knockout plants display reduced leaf angles and less sensitivity to 24-epiBL. In addition, both dla mutant and OsDLA knockout plants are more susceptible to rice blast compared to the wild type. OsDLA is a GRAS transcription factor and interacts with the BR signalling core negative regulator, GSK2. GSK2 phosphorylates OsDLA for degradation via the 26S proteasome. The GSK2 RNAi line exhibits enhanced rice blast resistance, while the overexpression lines thereof show susceptibility to rice blast. Furthermore, we show that OsDLA interacts with and stabilizes the WRKY transcription factor OsWRKY53, which has been demonstrated to positively regulate BR signalling and blast resistance. OsWRKY53 directly binds the promoter of PBZ1 and activates its expression, and this activation can be enhanced by OsDLA. Together, our findings unravel a novel mechanism whereby the GSK2-OsDLA-OsWRKY53 module coordinates blast resistance and plant architecture via BR signalling in rice.

Long-Term Temporospatial Complementary Relationship between Degradation and Bone Regeneration of Mg-Al Alloy.

The utilization of guided tissue regeneration membranes is a significant approach for enhancing bone tissue growth in areas with bone defects. Biodegradable magnesium alloys are increasingly being used as guided tissue regeneration membranes due to their outstanding osteogenic properties. However, the degradation rates of magnesium alloy bone implants documented in the literature tend to be rapid. Moreover, many studies focus only on the initial 3-month period post-implantation, limiting their applicability and impeding clinical adoption. Furthermore, scant attention has been given to the interplay between the degradation of magnesium alloy implants and the adjacent tissues. To address these gaps, this study employs a well-studied magnesium-aluminum (Mg-Al) alloy membrane with a slow degradation rate. This membrane is implanted into rat skull bone defects and monitored over an extended period of up to 48 weeks. Observations are conducted at various intervals (2, 4, 8, 12, 24, and 48 weeks) following the implantation. Assessment of degradation behavior and tissue regeneration response is carried out using histological sections, micro-CT scans, and scanning electron microscopy (SEM). The findings reveal that the magnesium alloy membranes demonstrate remarkable biocompatibility and osteogenic capability over the entire observation duration. Specifically, the Mg-Al alloy membranes sustain their structural integrity for 8 weeks. Notably, their osteogenic ability is further enhanced as a corrosion product layer forms during the later stages of implantation. Additionally, our in vitro experiments employing extracts from the magnesium alloy display a significant osteogenic effect, accompanied by a notable increase in the expression of osteogenic-related genes. Collectively, these results strongly indicate the substantial potential of Mg-Al alloy membranes in the context of guided tissue regeneration.

Morphological Changes in Total and Inferior Part of Maxillary Sinus After Le Fort I Osteotomy, as Determined by Cone-Beam Computed Tomography.

To investigate morphological changes of the total and inferior part of the maxillary sinus following Le Fort I osteotomy. 21 skeletal class II and 49 skeletal III patients who underwent orthognathic surgery were enrolled in this retrospective study. Cone-beam computed tomography taken before (T1) and 6 to 24 months after (T2) orthognathic surgery were imported into Mimics 20.0 software to analyze morphological changes of the total and inferior part of the maxillary sinus. Volume of the whole maxillary sinus was significantly reduced after surgery ( P ≤0.008), while the volume of the inferior part of the maxillary sinus was significantly greater than before surgery ( P ≤0.004). Maxillary sinus floor moved occlusally after Le Fort I osteotomy. Movement in the pitch direction of the posterior maxilla affected the state of the maxillary sinus mucosa after orthognathic surgery. Le Fort I osteotomy exerts a significant impact on the morphology of the total and inferior part of the maxillary sinus.

Influences of Extrusion and Silver Content on the Degradation of Mg-Ag Alloys In Vitro and In Vivo.

Binary magnesium-silver (Mg-Ag) alloys were designed as antibacterial materials for biomedical implant applications. In the present study, we focused on the effects of extrusion (extrusion ratio (ER): 1, 7.1, and 72.2) and Ag content (Ag = 0, 3, and 6 wt.%) on the degradation of Mg-Ag alloys in vitro and in vivo via microstructure characterization and corrosion/degradation measurements. The results showed that the Ag promoted a galvanic reaction with the Mg matrix to accelerate degradation or formed a protective oxide mesh texture to inhibit degradation, especially in vivo. Ag might also be beneficial for product crystallization, biomineralization, and organic matter deposition. For pure Mg, extrusion produced a more refined grain and decreased the degradation rate. For the Mg-Ag alloys, a low extrusion ratio (7.1) accelerated the degradation caused by the increase in the proportion of the precipitate. This promoted the release of Mg2+ and Ag+, which led to more deposition of organic matter and calcium phosphate, but also more H2 bubbles, which led to disturbance of product deposition in some local positions or even inflammatory reactions. Extrusion at a higher ratio (72.2) dissolved the precipitates. This resulted in moderate degradation rates and less gas production, which promoted osteogenesis without an obvious inflammation reaction.

The Rice Malectin Regulates Plant Cell Death and Disease Resistance by Participating in Glycoprotein Quality Control.

In animals, malectin is well known to play an essential role in endoplasmic reticulum quality control (ERQC) by interacting with ribophorin I, one unit of the oligosaccharyltransferase (OST) complex. However, the functions of malectin in plants remain largely unknown. Here, we demonstrate the rice OsMLD1 is an ER- and Golgi-associated malectin protein and physically interacts with rice homolog of ribophorin I (OsRpn1), and its disruption leads to spontaneous lesion mimic lesions, enhanced disease resistance, and prolonged ER stress. In addition, there are many more N-glycosites and N-glycoproteins identified from the mld1 mutant than wildtype. Furthermore, OsSERK1 and OsSERK2, which have more N-glycosites in mld1, were demonstrated to interact with OsMLD1. OsMLD1 can suppress OsSERK1- or OsSERK2-induced cell death. Thus, OsMLD1 may play a similar role to its mammalian homologs in glycoprotein quality control, thereby regulating cell death and immunity of rice, which uncovers the function of malectin in plants.

Three-Dimensional Dynamic Analysis of the Reproducibility of Verbal and Nonverbal Facial Expressions.

OBJECTIVE: The aim of this study is to compare the short- and long-term reproducibility of verbal and nonverbal facial expressions of normal people using dynamic 3-dimensional (3-D) imaging. DESIGN: Prospective, cross-sectional, controlled study. SETTING: Peking University School and Hospital of Stomatology, Beijing, China. PATIENTS AND PARTICIPANTS: Twenty-seven participants, 12 males and 15 females, were recruited for this study. METHODS: A 3-D dynamic system was applied to capture the process of 4 nonverbal facial expressions (smile lips closed, smile lips open, lip purse, cheek puff) and 2 verbal facial expressions (/i:/, /u:/) at an initial time point, 15 minutes later, and 1 week later. Key frames were selected from each expression recording sequence. MAIN OUTCOME MEASURES: The root mean square (RMS) between each key frame and its corresponding frame at rest was calculated. ΔRMS reflected the difference of the same key frames between the different sessions of the same expression of the same participant. The reproducibility of different facial expressions at different time intervals were analyzed. RESULTS: There was no significant difference in verbal and nonverbal expression repeatability during a 15-minute interval, except for cheek puff motion. Following a 1-week interval, verbal expression repeatability was superior to that of nonverbal expressions (P < .01). Compared with nonverbal expressions, the repeatability of verbal expressions did not obviously decrease with the increase in recording interval. CONCLUSIONS: Dynamic 3-D imaging is a useful technique for facial expression analysis. Verbal expressions showed greater reproducibility than nonverbal expressions.

OsNBL3, a mitochondrion-localized pentatricopeptide repeat protein, is involved in splicing nad5 intron 4 and its disruption causes lesion mimic phenotype with enhanced resistance to biotic and abiotic stresses.

Lesion mimic mutants are used to elucidate mechanisms controlling plant responses to pathogen attacks and environmental stresses. Although dozens of genes had been functionally demonstrated to be involved in lesion mimic phenotype in several plant species, the molecular mechanisms underlying the hypersensitive response are largely unknown. Here, a rice (Oryza sativa) lesion mimic mutant natural blight leaf 3 (nbl3) was identified from T-DNA insertion lines. The causative gene, OsNBL3, encodes a mitochondrion-localized pentatricopeptide repeat (PPR) protein. The nbl3 mutant exhibited spontaneous cell death response and H2 O2 accumulation, and displayed enhanced resistance to the fungal and bacterial pathogens Magnaporthe oryzae and Xanthomonas oryzae pv. oryzae. This resistance was consistent with the up-regulation of several defence-related genes; thus, defence responses were induced in nbl3. RNA interference lines of OsNBL3 exhibited enhanced disease resistance similar to that of nbl3, while the disease resistance in overexpression lines did not differ from that of the wild type. In addition, nbl3 displayed improved tolerance to salt, accompanied by up-regulation of several salt-associated marker genes. OsNBL3 was found to mainly participate in the splicing of mitochondrial gene nad5 intron 4. Disruption of OsNBL3 leads to the reduction in complex I activity, the elevation of alternative respiratory pathways and the destruction of mitochondrial morphology. Overall, the results demonstrated that the PPR protein-coding gene OsNBL3 is essential for mitochondrial development and functions, and its disruption causes the lesion mimic phenotype and enhances disease resistance and tolerance to salt in rice.

OsNBL1, a Multi-Organelle Localized Protein, Plays Essential Roles in Rice Senescence, Disease Resistance, and Salt Tolerance.

BACKGROUND: Plant senescence is a complicated process involving multiple regulations, such as temperature, light, reactive oxygen species (ROS), endogenous hormone levels, and diseases. Although many such genes have been characterized to understand the process of leaf senescence, there still remain many unknowns, and many more genes need to be characterized. RESULTS: We identified a rice mutant nbl1 with a premature leaf senescence phenotype. The causative gene, OsNBL1, encodes a small protein with 94 amino acids, which is conserved in monocot, as well as dicot plants. Disruption of OsNBL1 resulted in accelerated dark-induced leaf senescence, accompanied by a reduction in chlorophyll content and up-regulation of several senescence-associated genes. Notably, the nbl1 mutant was more susceptible to rice blast and bacterial blight but more tolerant to sodium chloride. Several salt-induced genes, including HAK1, HAK5, and three SNAC genes, were also up-regulated in the nbl1 mutant. Additionally, the nbl1 mutant was more sensitive to salicylic acid. Plants overexpressing OsNBL1 showed delayed dark-induced senescence, consistent with a higher chlorophyll content compared to wild-type plants. However, the overexpression plants were indistinguishable from the wild-types for resistance to the rice blast disease. OsNBL1 is a multi-organelle localized protein and interacts with OsClpP6, which is associated with senescence. CONCLUSIONS: We described a novel leaf senescence mutant nbl1 in rice. It is showed that OsNBL1, a multi-organelle localized protein which interacts with a plastidic caseinolytic protease OsClpP6, is essential for controlling leaf senescence, disease resistance, and salt tolerance.

A novel glycine-rich domain protein, GRDP1, functions as a critical feedback regulator for controlling cell death and disease resistance in rice.

Lesion mimic mutants constitute a valuable genetic resource for unraveling the signaling pathways and molecular mechanisms governing the programmed cell death and defense responses of plants. Here, we identified a lesion mimic mutant, spl-D, from T-DNA insertion rice lines. The mutant exhibited higher accumulation of H2O2, spontaneous cell death, decreased chlorophyll content, up-regulation of defense-related genes, and enhanced disease resistance. The causative gene, OsGRDP1, encodes a cytosol- and membrane-associated glycine-rich domain protein. OsGRDP1 was expressed constitutively in all of the organs of the wild-type plant, but was up-regulated throughout plant development in the spl-D mutant. Both the overexpression and knockdown (RNAi) of OsGRDP1 resulted in the lesion mimic phenotype. Moreover, the intact-protein level of OsGRDP1 was reduced in the spotted leaves from both overexpression and RNAi plants, suggesting that the disruption of intact OsGRDP1 is responsible for lesion formation. OsGRDP1 interacted with an aspartic proteinase, OsAP25. In the spl-D and overexpression plants, proteinase activity was elevated, and lesion formation was partially suppressed by an aspartic proteinase inhibitor. Taken together, our results reveal that OsGRDP1 is a critical feedback regulator, thus contributing to the elucidation of the mechanism underlying cell death and disease resistance.

Three-Dimensional Dynamic Analysis of the Facial Movement Symmetry of Skeletal Class III Patients With Facial Asymmetry.

PURPOSE: Dynamic asymmetry has not been as rigorously evaluated as static asymmetry for patients with skeletal deformity but could well be even more important. The aim of the present study was to evaluate the dynamic facial movement of Class III patients with facial asymmetry using a 3-dimensional (3D) motion capture system. MATERIALS AND METHODS: The present cross-sectional study recruited patients with skeletal Class III malocclusion with and without facial asymmetry. A 3D facial motion capture system was used to record the expression process of a maximal smile. Eleven orofacial landmarks were selected to analyze and calculate the cumulative distance and average speed of each landmark during smiling. The predictor variable was mandibular symmetry. The outcome variables consisted of the measurements of each soft tissue landmark and the absolute differences for the paired landmarks between 2 sides. Other variables consisted of descriptive data, including the age and gender of each patient. The data were analyzed using independent t tests and paired t tests. Bonferroni's adjustment was used to control for multiple comparisons. RESULTS: A total of 63 patients were divided into 2 groups, an asymmetric group (n = 46) and a control group (n = 17), according to the degree of skeletal deviation. The difference in the cumulative distance of the bilateral cheilions was statistically significant between the 2 groups (P = .002). The difference for the asymmetric and control groups was 2.06 ± 1.78 mm and 1.00 ± 0.79 mm, respectively. In the asymmetric group, a comparison of the deviated side with the nondeviated side revealed statistically significant differences in the magnitude of motion for the cheilion (P < .01) and midlateral lower lip (P < .01). CONCLUSIONS: The patients with skeletal asymmetry also showed asymmetry in soft tissue functions while smiling. The magnitude of movement in the nondeviated side was greater than that in the deviated side.

Bay- and Ortho-Octasubstituted Perylenes.

A key intermediate compound, 2,5,8,11-tetrabromo-1,6,7,12-tetrabutoxyperylene (Per-4Br), was synthesized from 3,6-dibromo-2,7-dioxylnaphthalene via simple regioselective oxidative radical-radical coupling, followed by reduction and nucleophilic substitution. Various bay- and ortho-octasubstituted perylenes containing cyano, methoxy and aryl groups were then obtained by nucleophilic substitution or Pd-catalyzed coupling reactions. X-ray crystallographic analyses reveal that these new perylene molecules process a twisted structure due to steric congestion at the bay-regions and there is no obvious intermolecular π-π interaction. As a result, they exhibit moderate fluorescence quantum yields even in solid state. Therefore, Per-4Br can serve as a versatile building block for various functional perylene dyes with tunable optoelectronic property.

A facile approach toward 1,2-diazabenzo[ghi]perylene derivatives: structures and electronic properties.

A new class of pyridazine fused aromatics, 1,2-diazabenzo[ghi]perylenes, is conveniently synthesized from 2,7-dihydroxynaphthalene via intermolecular oxidative coupling followed by a condensation reaction. These new compounds are fully characterized via X-ray crystallographic analysis, optical spectroscopy and electrochemistry, in addition to DFT calculations. They show a twisted structure and unique P-/P- and M-/M-enantiomer pairs are observed in their single crystals. They exhibit intramolecular charge transfer character and emit at a longer wavelength with a larger Stokes shift compared with their all-carbon analog.

Towards perylenequinonoid: Effective application to reversible fluorescent probe for monitoring hydrogen persulfide in solvents and living cells.

Hydrogen persulfide (H2S2), as a direct redox form of H2S, may have its own physiological processes in maintaining intracellular redox homeostasis. The research on hydrogen persulfide was rapidly growing. As it is the actual signalling molecules derived from hydrogen sulfide, reversible detection of hydrogen persulfide changes in cells is of great significance. To address this critical need, we present a reversible fluorescent switch-on H2S2 probe, the tautomeric of 6, 7-dihydroxyperylene-1, 12-quinone (DHPQ), capable of tracking H2S2 in solvents and living cells. The probe can be applied to quantified H2S2 expressions ranging linearly from 2.0×10-6 to 2.0×10-5 M. The limit of detection was found to be 1.82×10-8M. In addition, the fluorescent alterations are remarkably specific for H2S2 in the presence of other reactive sulfur species. These features are favorable for imaging application. Taking advantage of favorable cycle stability and admirable selectivity, the DHPQ dye can be used as a reversible fluorescent platform to construct novel H2S2 probes. Since such reversible H2S2 probes are rare, this work provide a potential approach for reversible probing fluctuation of hydrogen persulfide in biological systems.