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Communication between insects and plants relies on the exchange of bioactive molecules that traverse the species interface. Although proteinic effectors have been extensively studied, our knowledge of other molecules involved in this process remains limited. In this study, we investigate the role of salivary microRNAs (miRNAs) from the rice planthopper Nilaparvata lugens in suppressing plant immunity. A total of three miRNAs were confirmed to be secreted into host plants during insect feeding. Notably, the sequence-conserved miR-7-5P is specifically expressed in the salivary glands of N. lugens and is secreted into saliva, distinguishing it significantly from homologues found in other insects. Silencing miR-7-5P negatively affects N. lugens feeding on rice plants, but not on artificial diets. The impaired feeding performance of miR-7-5P-silenced insects can be rescued by transgenic plants overexpressing miR-7-5P. Through target prediction and experimental testing, we demonstrate that miR-7-5P targets multiple plant genes, including the immune-associated bZIP transcription factor 43 (OsbZIP43). Infestation of rice plants by miR-7-5P-silenced insects leads to the increased expression of OsbZIP43 , while the presence of miR-7-5P counteracts this upregulation effect. Furthermore, overexpressing OsbZIP43 confers plant resistance against insects which can be subverted by miR-7-5P. Our findings suggest a mechanism by which herbivorous insects have evolved salivary miRNAs to suppress plant immunity, expanding our understanding of cross-kingdom RNA interference between interacting organisms., Competing Interests: Competing interests statement:The authors declare no competing interest.

Purpose: To evaluate the clinical aesthetic effect of buccal alveolar ridge preservation (ARP) and connective tissue transplantation (CTG) in patients who received a single implant., Methods: Forty-three patients with tooth loss admitted to the Department of Stomatology of Shunde Hospital of Southern Medical University from May 2014 to May 2016 were included in the study. Tooth extraction, ARP, implant implantation, CTG and permanent repair were performed respectively. The incidence of bleeding, depth of probing, marginal bone resorption, and red-white aesthetic effect of implants were evaluated 1 year and 3 years after surgery. The buccal mucosa thickness of implants before, immediately after CTG, 1 year and 3 years after surgery were measured. The patient satisfaction was evaluated by visual analogue scale (VAS) from masticatory function, overall aesthetics, attachment height, and color, respectively. The implant conditions at the third year after surgery were observed, and complications during follow-up were recorded. SPSS 20.0 software package was used for statistical analysis of the data., Results: The follow-up rate in the first year after surgery was 100%, and that in the third year after surgery was 90.70%. One year and 3 years after operation, the aesthetic effect of the implant was satisfactory. At the 3rd year after operation, the scores of the near middle gingival papillary were significantly higher than that at the 1st year after operation (P<0.05). The buccal mucosal thickness of the implant immediately after CTG and 1 year and 3 years after surgery increased significantly compared with that before CTG (P<0.05). The buccal mucosal thickness of the implant increased 1.02 mm (relative stability: 90.12%) 1 year after operation and 1.01 mm (relative stability: 84.31%) 3 years after operation, respectively. The satisfaction scores of the patients on chewing function, overall aesthetics, attachment height and color of the implant immediately after CTG, one year after surgery and 3 years after surgery were all > 8. The 3-year survival rate of the implants was 100%, and the 3-year success rate of the implants was 97.44%. During the follow-up, two patients developed peri-implant mucositis, which was relieved after tooth cleaning, but no complications such as tissue flap necrosis, limited opening and tongue movement disorder occurred., Conclusions: ARP and CTG have good clinical and aesthetic effects on patients with tooth loss. In three years, the buccal mucosal thickness of the implant can be increased and relatively stable, which is worthy of clinical promotion and application.

Skeletal muscle-derived cells have strong secretory function, while skeletal muscle-derived stem cells, which are included in muscle-derived cells, can differentiate into Schwann cell-like cells and other cell types. However, the effect of muscle-derived cells on peripheral nerve defects has not been reported. In this study, 5-mm-long nerve defects were created in the right sciatic nerves of mice to construct a peripheral nerve defect model. Adult female C57BL/6 mice were randomly divided into four groups. For the muscle-derived cell group, muscle-derived cells were injected into the catheter after the cut nerve ends were bridged with a polyurethane catheter. For external oblique muscle-fabricated nerve conduit and polyurethane groups, an external oblique muscle-fabricated nerve conduit or polyurethane catheter was used to bridge the cut nerve ends, respectively. For the sham group, the sciatic nerves on the right side were separated but not excised. At 8 and 12 weeks post-surgery, distributions of axons and myelin sheaths were observed, and the nerve diameter was calculated using immunofluorescence staining. The number, diameter, and thickness of myelinated nerve fibers were detected by toluidine blue staining and transmission electron microscopy. Muscle fiber area ratios were calculated by Masson's trichrome staining of gastrocnemius muscle sections. Sciatic functional index was recorded using walking footprint analysis at 4, 8, and 12 weeks after operation. The results showed that, at 8 and 12 weeks after surgery, myelin sheaths and axons of regenerating nerves were evenly distributed in the muscle-derived cell group. The number, diameter, and myelin sheath thickness of myelinated nerve fibers, as well as gastrocnemius muscle wet weight and muscle area ratio, were significantly higher in the muscle-derived cell group compared with the polyurethane group. At 4, 8, and 12 weeks post-surgery, sciatic functional index was notably increased in the muscle-derived cell group compared with the polyurethane group. These criteria of the muscle-derived cell group were not significantly different from the external oblique muscle-fabricated nerve conduit group. Collectively, these data suggest that muscle-derived cells effectively accelerated peripheral nerve regeneration. This study was approved by the Animal Ethics Committee of Plastic Surgery Hospital, Chinese Academy of Medical Sciences (approval No. 040) on September 28, 2016., Competing Interests: None

Objective: To study the effects of ultraviolet (UV) light-treatment on the physicochemical properties and bioactivity of micro-arc oxidation (MAO) titanium surfaces in vitro., Methods: The pure titanium were prepared using MAO. MAO titanium samples were treated with 15 W bactericidal lamp UVC [λ = (250 ± 20) nm] or 15 W mercury lamp [λ = (360 ± 20) nm] for 24 h under ambient conditions. Three sample groups were prepared: MAO, UVA treated after MAO (MAO + UVA), UVC treated after MAO (MAO + UVC). The surface physicochemical properties were evaluated using scanning electron microscopy (SEM), contact angle measuring device, energy dispersive X-ray spectrometer (EDX), and X-ray diffraction (XRD). Bicinchoninic acid (BCA) based colorimetric detection was used to quantify the percentage of albumin adsorption after 2 h, 6 h, and 24 h incubation on the titanium surfaces. The rates of MG-63 cells attached to each group titanium surfaces were calculated by nucleus immunofluorescence using Hoechst 33342 after 1 h, 2 h, and 4 h incubation. SEM was used to observe cell morphology on titanium surfaces in each group., Results: No obvious differences in surface topography, TiO(2) crystal and elemental composition were detected on titanium surfaces with or without UV treatment. Statistically significant difference in contact angles among MAO + UVC group (65.34 ± 1.16)°, MAO + UVA group (44.64 ± 1.28)°, and MAO group (3.41 ± 0.48)° were found (P < 0.001). The percentage of albumin adsorption reached the plateau after 2 h incubation on MAO + UVC titanium surfaces (48.16 ± 1.24)%, which was higher than those in MAO [(8.22 ± 2.99)%] and MAO + UVA groups [(5.29 ± 2.27)%, P < 0.001]. The rates of cells attached to the surfaces of MAO + UVC titanium was greater than that on MAO surfaces and MAO + UVA surfaces after 1 h [(40.71 ± 4.08)%], 2 h [(53.72 ± 2.38)%], 4 h [(70.32 ± 2.85)%] incubation (P < 0.05). The MAO + UVC surfaces remarkably enhanced the spread of MG-63 cells, however, there was no significant difference between the group of MAO and MAO + UVA., Conclusions: Pretreatment of micro-arc oxidation titanium with UVC light considerably improved the surface bioactivity to MG-63 cells, which showed an increase in cellular attachment and spread.