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Simple Summary: Entomopathogenic nematodes and their symbiotic bacteria are widely utilized for biological control. However, whether nematode-derived signals influence the immune response of insects remains unexplored. In this study, we provide comprehensive insight into the interactions among symbiotic bacteria, nematode pheromone ascarosides, and the G. mellonella insect host. Our findings reveal that under the induction of Photorhabdus bacteria, ascarosides enhance the host's immunity response. Specifically, they suppress the intensity of body color change and increase the expression of related-immunity gene expression. Additionally, ascarosides reduce the Photorhabdus cell load and delay G. mellonella larval mortality. These results imply that G. mellonella larvae may employ nematode pheromones to enhance insect immunity in the presence of symbiotic bacteria, thereby enhancing the resistance to invasive bacteria. Insects protect themselves through their immune systems. Entomopathogenic nematodes and their bacterial symbionts are widely used for the biocontrol of economically important pests. Ascarosides are pheromones that regulate nematode behaviors, such as aggregation, avoidance, mating, dispersal, and dauer recovery and formation. However, whether ascarosides influence the immune response of insects remains unexplored. In this study, we co-injected ascarosides and symbiotic Photorhabdus luminescens subsp. kayaii H06 bacteria derived from Heterorhabditis bacteriophora H06 into the last instar larvae of Galleria mellonella. We recorded larval mortality and analyzed the expressions of AMPs, ROS/RNS, and LPSs. Our results revealed a process in which ascarosides, acting as enhancers of the symbiotic bacteria, co-induced G. mellonella immunity by significantly increasing oxidative stress responses and secreting AMPs (gallerimycin, gloverin, and cecropin). This led to a reduction in color intensity and the symbiotic bacteria load, ultimately resulting in delayed host mortality compared to either ascarosides or symbiotic bacteria. These findings demonstrate the cross-kingdom regulation of insects and symbiotic bacteria by nematode pheromones. Furthermore, our results suggest that G. mellonella larvae may employ nematode pheromones secreted by IJs to modulate insect immunity during early infection, particularly in the presence of symbiotic bacteria, for enhancing resistance to invasive bacteria in the hemolymph. [ABSTRACT FROM AUTHOR]

Polarized growth plays a key role in all domains of their biology, including morphogenesis and pathogenicity of filamentous fungi. However, little information is available about the determinants of polarized growth. The fungal Mep2, Pes1, and Cph1 proteins were identified to be involved in the dimorphic transition between yeast and hyphal forms in Candida albicans. In this study, evidence that the dimorphic fungal entomopathogen Ophiocordyceps sinensis Mep2, Pes1, and Cph1 proteins are involved in polarized growth is presented. OsMep2 was significantly upregulated at aerial hyphae and conidia germination stages. OsCph1 was significantly upregulated at aerial hyphae, conidia initiation, and conidia germination stages, and OsPes1 was significantly upregulated at the conidia germination stage. Deletions of OsMep2 , OsCph1 , and OsPes1 provoked defects in the polarized growth. The abilities of hyphal formation and the yields of blastospores and conidia for the ∆  OsMep2 , ∆ OsCph1 , and ∆  OsPes1 mutants were significantly reduced. The conidia yields of the Δ OsMep2 , Δ OsCph1 , and Δ OsPes1 mutants were decreased by 69.17%, 60.90%, and 75.82%, respectively. Moreover, the pathogenicity of the ∆  OsMep2 , ∆ OsCph1 , and ∆  OsPes1 mutants against Thitarodes xiaojinensis was significantly reduced. The mummification rate caused by wide type and Δ OsMep2 , Δ OsCph1 , and Δ OsPes1 mutants were 36.98% ± 8.52%, 0.31% ± 0.63%, 1.15% ± 1.57%, and 19.69% ± 5.6%, respectively. These results indicated that OsMep2 , OsCph1 , and OsPes1 are involved in the regulation of hyphal formation, sporulation, and pathogenicity of O. sinensis. This study provided a basis for the understanding of the fungal dimorphic development and improving the efficiency of artificial cultivation of O. sinensis. [ABSTRACT FROM AUTHOR]

The study aimed to explore an extra-articular screw placement strategy in Stoppa approach. Radiographic data of patients who underwent pelvic computed tomography from January 2016 to June 2017 were imported into Materiaise's interactive medical image control system software for three-dimensional reconstruction. Superior and lower margins of acetabulum and ipsilateral pelvic brim could be observed simultaneously through inlet-obturator view. A horizontal line from superior acetabular margin intersected pelvic brim at point "A" and another vertical line from lower margin intersected pelvic brim at point "B" were drawn, respectively. Lengths form sacroiliac joint to "A" (a), "A" to "B" (b), and "B" to pubic symphysis (c) were measured. Patients were divided into four groups depending on gender and side difference of measured hemi-pelvis: male left, male right, female left, and female right. Lengths of adjacent holes (d) and spanning different holes (e) of different plates were also measured. Mean lengths of a, b, c in four groups were 40.94 ± 1.85 mm, 40.09 ± 1.93 mm, 41.78 ± 3.62 mm, and 39.77 ± 2.23 mm (P = 0.078); 40.65 ± 1.58 mm, 41.48 ± 1.64 mm, 40.40 ± 1.96 mm, and 40.66 ± 1.70 mm (P = 0.265); 57.03 ± 3.41 mm, 57.51 ± 3.71 mm, 57.84 ± 4.40 mm, and 59.84 ± 4.35 mm (P = 0.165), respectively. Mean d length of different plates was 12.23 mm. Average lengths spanning 1, 2, 3 and 4 holes were 19.33 mm, 31.58 mm, 43.80 mm, and 55.93 mm. Our data showed that zones a and c could be safely inserted three and four screws. Penetration into hip joint could be avoided when vacant 3-hole drilling was conducted in zone b. Fracture line in zone b could serve as a landmark for screw placement. [ABSTRACT FROM AUTHOR]