DEGENERATED LEMMA (DEL) regulates lemma development and affects rice grain yield.

In grass, the lemma is a unique floral organ structure that directly determines grain size and yield. Despite a great deal of research on grain enlargement caused by changes in glume cells, the importance of normal development of the glume for normal grain development has been poorly studied. In this study, we investigated a rice spikelet mutant, degenerated lemma (del), which developed florets with a slightly degenerated or rod-like lemma. More importantly, del also showed a significant reduction in grain length and width, seed setting rate, and 1000-grain weight, which led to a reduction in yield. The results indicate that the mutation of the DEL gene further affects rice grain yield. Map-based cloning shows a single-nucleotide substitution from T to A within Os01g0527600/DEL/OsRDR6, causing an amino acid mutation of Leu-34 to His-34 in the del mutant. Compared with the wild type, the expression of DEL in del was significantly reduced, which might be caused by single base substitution. In addition, the expression level of tasiR-ARF in del was lower than that of the wild type. RT-qPCR results show that the expression of some floral organ identity genes was changed, which indicates that the DEL gene regulates lemma development by modulating the expression of these genes. The present results suggest that the normal expression of DEL is necessary for the formation of lemma and the normal development of grain morphology and therefore has an important effect on the yield. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-023-01297-6.

Determination of permissible contact stress of case hardened raceway of roller slewing bearing.

The permissible contact stress for the rolling bearing made of the through hardened bearing steel has been established based on experience, while there is no definite value or calculating formula of the permissible contact stress for the slewing bearings which are hardened only on the raceway surface yet. To determine the permissible contact stress of the case hardened raceway of roller slewing bearing, finite element analysis for the contact elasto-plastic characteristics between the loaded roller and the case hardened raceway was performed, and the contact plastic deformations corresponding to different roller diameter, roller load, and case depth were obtained. The contact stress produced by the roller load was calculated by using Hertz contact theory. Based on the nonlinear regression analysis between the input parameters and the output plastic deformations of the model, the relation equation between the contact plastic deformation and the roller diameter, contact stress, case depth was established. The formula for calculating the permissible contact stress of the case hardened raceway was obtained according to the regression equation further. The permissible contact stresses calculated by using the obtained formula show that the permissible contact stress of the case hardened raceway depends mainly on the case depth. Loaded compression tests between the roller and the case hardened specimens were conducted to verify the validity of the established calculation method for the permissible contact stress of the case hardened raceway. Permissible contact stress decreases slightly with the increase of the roller diameter and increases with the increase of the case depth significantly. As the case depth reaches 6 mm, the maximum permissible contact stress is 3758 MPa. As the case depth reaches 7 mm, the maximum permissible contact stress of the case hardened raceway is 3889 MPa.

Genipin alleviates vascular hyperpermeability following hemorrhagic shock by up-regulation of SIRT3/autophagy.

Genipin (GP) is commonly used to treat cardiovascular diseases; however, the protective action of GP against vascular hyperpermeability (VH) has not been reported. We previously reported that intrinsic apoptotic signaling (IAS) is involved in VH following hemorrhagic shock (HS). GP inhibits apoptosis, but the specific mechanism remains unclear. In the present study, we observed that GP protects against HS-induced VH in vitro and in vivo. We report that this protective effect is related to the inhibition of IAS by up-regulation of autophagy via sirtuin 3 (SIRT3). The endothelial cell hyperpermeability induced by HS was enhanced by GP; this was attenuated by 3-methyladenine (3MA), a specific inhibitor of autophagy, indicating the involvement of autophagy. Consistent with these results, we found that 3MA reversed the effects of GP on up-regulation of autophagy, and also diminished the protective effect of GP against IAS activation following HS. Furthermore, knockout of SIRT3 inhibited GP-induced autophagy, indicating the requirement of SIRT3 in the regulation of autophagy by GP. In rats, GP improved HS-induced VH, which was repressed by 3MA and 3-(1H-1,2,3-triazol-4-yl)pyridine (3-TYP), a SIRT3 inhibitor. In conclusion, these findings suggest that autophagy plays a protective effect in VH following HS; the protective effect of autophagy is reinforced by GP, which protects against IAS and VH by up-regulating SIRT3.

[Evaluation for vertical stability after various orthognathic surgical treatment plans for skeletal class â ¢ malocclusion with anterior open-bite].

OBJECTIVE: To evaluate vertical stability after various orthognathic surgical treatment plans for skeletal class Ⅲ malocclusion with anterior openbite. METHODS: A retrospective multicenter cohort study was conducted to investigate vertical stability after various orthognathic surgical treatment plans for skeletal class Ⅲ malocclusion with anterior openbite. From 2010-2016, 122 patients from two domestic stomatological hospitals were included in our study. Patients were divided into four groups according to their treatment plans, namely, bilateral sagittal split ramus osteotomy (BSSRO), intraoral vertical ramus osteotomy (IVRO), BSSRO+Le Fort Ⅰ, and IVRO+Le Fort Ⅰ. All patients followed a standardized examination procedure at 6 and 24 months post-treatment. The observation indexes include overbite, mandibular plane angle, and intermaxillary angle. RESULTS: 1) The significantly reduced ratio of the overbite in the BSSRO+Le Fort Ⅰ and IVRO+Le Fort Ⅰ groups were less than the BSSRO and IVRO groups at 6 and 24 months post-treatment. 2) The significantly increased ratio of the mandibular plane in BSSRO+Le Fort Ⅰ and IVRO+Le Fort Ⅰ groups were less than BSSRO and IVRO groups at 6 and 24 months post-treatment. 3) The significantly increased ratio of the intermaxillary angles in BSSRO+Le Fort Ⅰ and IVRO+Le Fort Ⅰ groups were less than the BSSRO and IVRO groups at 6 months post-treatment, while there was no statistical difference at 24 months post-treatment. CONCLUSIONS: Bimaxillary surgery (BSSRO+Le Fort Ⅰ and IVRO+Le Fort Ⅰ) is more effective than mandibular surgery to control vertical relapse.

[Efficacy of systemic administration of oxytocin on implant osseointegration in osteoporotic rats].

OBJECTIVE: This study investigated the effects of systemic administration of oxytocin (OT) in osteoporotic rats on implant osseointegration. METHODS: Twenty rats were randomly assigned to the control and experimental groups. Initially, the rats underwent bilateral ovariectomy. After 12 weeks, an osteoporosis model was established. Each rat received an implant at the distal and middle femoral metaphysis. Simultaneously, systemic administration was conducted with one group receiving subcutaneous injection of OT (1 mg·kg⁻¹ per day), whereas the other group received placebo injection. After treatment for 4 weeks, another surgery was conducted to remove the thigh bones from the rats containing the implants for an eight-week observation. With the employment of micro-CT, histological observation and push-out test, osseointegration was evaluated. While the rats received thigh-bone removal surgery, another surgery was conducted to remove the tibia metaphysis from the rats of both groups to perform histological observation and micro-CT inspection. RESULTS: The trabecular bone of tibial samples was intensive and formed woven mesh structure in the experimental group compared with the control group. In the experimental group, the relative bone volume/tissue volume surrounding the implant, the bone contact ratio, and the maximum push-out force of the implant were 0.35%±0.06%, 67.25%±9.06%, and (70.32±10.91) N, respectively, the corresponding values were 0.11%±0.02%, 43.25%±7.01% and (21.65±4.36) N in the control group, and the experimental group increased significantly compared with the control group (P<0.05). CONCLUSIONS: Systemic administration of OT cannot only antagonize the negative effects of osteoporosis but can also promote implant healing and osseointegration of pure titanium implants.