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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]

Purpose. K-wire with tension band (KTB) technique has long been the primary surgical method for transverse patella fractures; however, it also has shortcomings. This study is aimed at evaluating the three different techniques to see whether the cannulated screw tension band (CSTB) or ring pin tension band (RPTB) techniques could decrease complications and achieve better knee function compared with KTB. Methods. We conducted a retrospective comparison of the KTB, CSTB, and RPTB fixation techniques. We selected and reviewed 90 patients (30 patients in each fixation group) with follow-up at least 2 years. Duration of operation, intraoperative blood loss, mean healing time, visual analog scale score, range of motion, Böstman score, Iowa knee score, modified Lysholm rating scale, and postoperative complications were compared. Multivariate analyses were performed to identify the independent risk factors for fracture healing time, postoperative complications, and knee function recovery. Results. After adjusting for confounding factors, multivariate regression analysis revealed that CSTB was 0.26 times (95% CI: 0.08-0.86, p = 0.027) less likely to prolong fracture healing time, 0.20 times (95% CI: 0.06-0.64, p = 0.007) lesser risk of postoperative complications, and more than four times (95% CI: 1.41-13.56, p = 0.011) as likely to improve the knee function score compared with KTB. Besides, RPTB were also superior to KTB in reducing the incidence of postoperative complications (OR: 0.21, 95% CI: 0.07-0.64, p = 0.006) and improved knee function score (OR: 3.96, 95% CI: 1.30-12.08, p = 0.016); however, the CSTB group being more superior. In addition, AO/OTA C2 fractures (OR, odds ratio: 10.68, 95% CI: 1.30-87.70, p = 0.027) and high-energy fracture (OR: 8.78, 95% CI: 1.57-49.17, p = 0.013) were also associated with prolonged fracture healing time but not with postoperative complications and knee function. No significant differences in related indicators such as gender, age, BMI, AO/OTA classification, fracture side, injury mechanism, duration of operation, and intraoperative blood loss were detected among the three groups. Conclusion. This study demonstrated that the CSTB technique is superior to KTB and RPTB techniques in reducing the incidence of postoperative complications, and it also has advantages in accelerating fracture healing, achieving better VAS, ROM, and functional recovery. Further long-term large-sized prospective randomized trials are needed to evaluate the efficacy of the KTB in treating transverse patellar fractures. [ABSTRACT FROM AUTHOR]

The current commercial production of natural astaxanthin is mainly carried out using Haematococcus pluvialis vegetative cells in the "two-stage" batch mode. The motile vegetative cells are more sensitive to stress than nonmotile vegetative cells, thereby affecting the overall astaxanthin productivity in H. pluvialis cultures. In this study, we compared the differences between motile cells and nonmotile cells in astaxanthin productivity, morphological changes, the mortality rate, and the diameter of the formed cysts. The experimental design was achieved by two different types H. pluvialis cell under continuous light of 80 μmol photons m−2 s−1 for a 9-day induction period. The highest astaxanthin concentration of 48.42 ± 3.13 mg L−1 was obtained in the nonmotile cell cultures with the highest the productivity of 5.04 ± 0.15 mg L−1 day−1, which was significantly higher than that in the motile cell cultures. The microscopic examination of cell morphological showed a large number of photooxidative damaged cells occurring in the motile cell cultures, resulting in higher cell mortality rate (22.2 ± 3.97%) than nonmotile cell cultures (9.6 ± 0.63%). In addition, the analysis results of cell diameter statistics indicated that nonmotile cells were more conducive to the formation of large astaxanthin-rich cysts than motile cells. In conclusion, the works presented here suggest that the accumulation of astaxanthin was significantly improved by nonmotile cells of H. pluvialis, which provided a possibility of optimizing the existing H. pluvialis cultivation strategy for the industrial production. [ABSTRACT FROM AUTHOR]

Ge, H.; Chen, D.; Li, S.; Zheng, A.; Zhu, Z., and Zheng, X., 2019. Determination of Fe, Ti in seawater using a flow-injection pretreatment system with ICP-MS. In: Guido-Aldana, P.A. and Mulahasan, S. (eds.), Advances in Water Resources and Exploration. Journal of Coastal Research, Special Issue No. 93, pp. 77–82. Coconut Creek (Florida), ISSN 0749-0208. In order to solve the interference caused by low metal concentration and salts matrix of seawater samples, this paper present a handy flow- injection system with solid-phase extraction to automate pretreatment procedures for offline Fe and Ti analysis in seawater by ICP-MS. By combining 8-position, 3-way and 6-way valves in the pipeline, the flow-injection system enhance the sample treatment efficiency by simultaneously loading two reagents online for: sample loading, buffering, and preconcentration. Each sample treatment spends about 16 min and consumes 12 mL of seawater sample and 8 mL of buffer solution. The chelation of Toyopearl-AF-Chelate-650M for Fe and Ti occurs in pH5.5 at an injection rate of 1.0 mL·min-1. The eluent (0.8 mol·L-1 HNO3) is able to elute Fe and Ti in 90 s at an elution rate of 1.0 mL·min-1. Seawater sample needs 90 min of 120 W UV-oxidation to dissociate metal-organic complexes. The precision and availability of this method are tested by measuring Jiulongjiang Estuary seawater samples. [ABSTRACT FROM AUTHOR]

Liu, C.; Chen, D.; Zheng, X., and Zheng, A., 2019. The content and distribution of nitrogen in nature colloids from Jiulongjiang River. In: Guido-Aldana, P.A. and Mulahasan, S. (eds.), Advances in Water Resources and Exploration. Journal of Coastal Research, Special Issue No. 93, pp. 70–76. Coconut Creek (Florida), ISSN 0749-0208. The content, distribution and seasonal variations of nitrogen in nature colloids were examined in surface waters of south Xiamen Bay, Jiulongjiang River estuary and Jiulongjiang River of China. Water samples were fractionated into total dissolved (< 0.2 µm), colloidal (10 kDa-0.2 µm) and truly dissolved (< 10 kDa) phases with the cross-flow ultrafiltration system. Results showed that average concentrations of different nitrogen species in truly dissolved phase were evidently higher than those in colloidal phase, and concentrations of NO2-, NO3-, NH4+, TN, TIN, and ON were 52, 238, 18, 9, 39 and 3 times higher respectively. In addition, NO3- was the most abundant inorganic species and was 11-28 times as high as NH4+ and NO2- in truly dissolved phase, but 2-15 times as high as NH4+ and NO2- in colloidal phase. NO2-, NO3-, NH4+, TN, and TIN in truly dissolved phase make up 77.2%-100.0% of that in total dissolver phase while those of colloidal phase make up only 0-19.0%; ON contents in truly dissolved phase made up 42.2%-69.3% of that in total dissolved phase while those of the colloidal phase made up 30.7%-57.9% of them. This indicated that IN species were distributed mainly in truly dissolved phase (< 10 kDa) in natural aquatic environments, and ON was distributed mainly in colloidal phase (10 kDa-0.22 µm). It was also found that the seasonal variations of all N species in truly dissolved phase was similar to that of total dissolved phase in all waters from different sources. There was slight variation of NO2- and NH4+ with season. The NO3- was highest in April and March and lowest in August and November. The seasonal variation of ON was related to the water sources. The contents of all N species in both dissolved phase and truly dissolved phase decreased from river to sea. [ABSTRACT FROM AUTHOR]

A determination method for metalaxyl(MEL) residues in watermelon and banana had been established by automated solid-phase extraction(SPE) coupled with high performance liquid hromatography(HPLC). Samples were extracted by acetonitrile, homogenized, filtrated, extracted by automated solid-phase extraction(SPE), and finally purified by C18 column. The experiment was carried on SunFireTM C18 column with the mobile phase of acetonitrile-water-methanol(25:40:35, by vol) at the flow rate of 1.0 mL/min. The detection wavelength and injection volume were set at 220 nm and 10 uL, respectively. The recoveries of three different concentrations(0.02, 0.20, 1.00 mg/kg) for watermelon and banana were 94.3%-101.0% and 81.5%-99.6%, respectively. RSD(n = 5)were 1.30%-5.29% and 2.66%-6.67%, respectively. The lower detection limit for metalaxyl was 0.006 mg/kg. This method met with the requirements of pesticide residue detection. [ABSTRACT FROM AUTHOR]

Simple Summary: The ghost moth, Thitarodes sp., is an obligate host of the most precious fungus Ophiocordyceps sinensis on Tibetan plateau. Artificial rearing of the ghost moth at low-altitude laboratory by mimicking the environment of the wild habitat for the cultivation of the Chinese cordyceps has been realized. However, the high mortality of ghost moth larvae by pathogens, low and slow infection, and mummification rate by O. sinensis still constrain the efficient cultivation of the Chinese cordyceps. Both larval gut microbiota and their exploitation in the Thitarodes artificial rearing system have attracted a renewed interest. In the present study, the gut bacterial and fungal communities of the wild and laboratory-reared populations were characterized using both culture-dependent and -independent approaches. The discovery of apparent microbial community shifts between the wild and laboratory-reared ghost moth larvae, many opportunistic pathogenic bacteria and fungi in the gut of the laboratory-reared ghost moth larvae, and the dominant bacteria enriched in the wild ghost moth provide interesting cues for selecting beneficial probiotic bacteria to improve the effectiveness of Thitarodes rearing system and the cultivation of the Chinese cordyceps. By employing a culture-dependent and -independent 16S rRNA and ITS gene high-throughput sequencing analyses, comprehensive information was obtained on the gut bacterial and fungal communities in the ghost moth larvae of three different geographic locations from high-altitude on Tibet plateau and from low-altitude laboratory. Twenty-six culturable bacterial species belonging to 21 genera and 14 fungal species belonging to 12 genera were identified from six populations by culture-dependent method. Carnobacterium maltaromaticum was the most abundant bacterial species from both the wild and laboratory-reared larvae. The most abundant OTUs in the wild ghost moth populations were Carnobacteriaceae, Enterobacteriaceae for bacteria, and Ascomycota and Basidiomycota for fungi. Larval microbial communities of the wild ghost moth from different geographic locations were not significantly different from each other but significant difference in larval microbial community was detected between the wild and laboratory-reared ghost moth. The larval gut of the wild ghost moth was dominated by the culturable Carnobacterium. However, that of the laboratory-reared ghost moth exhibited significantly abundant Wolbachia, Rhizobium, Serratia, Pseudomonas, and Flavobacterium. Furthermore, the larval gut of the wild ghost moth had a significantly higher abundance of Ophiocordyceps but lower abundance of Candida and Aspergillus than that of the laboratory-reared ghost moth. [ABSTRACT FROM AUTHOR]

Astaxanthin from H. pluvialis is an antioxidant and presents a promising application in medicine for human health. The two-stage strategy has been widely adopted to produce astaxanthin by the Haematococcus industry and research community. However, cell death and low astaxanthin productivity have seriously affected the stability of astaxanthin production. This study aims to test the effect of cell transformation strategies on the production of astaxanthin from H. pluvialis and determine the optimal initial biomass density (IBD) in the red stage. The experimental design is divided into two parts, one is the vegetative growth experiment and the other is the stress experiment. The results indicated that: (1) the cell transformation strategy of H. pluvialis can effectively reduce cell death occurred in the red stage and significantly increase the biomass and astaxanthin production. (2) Compared with the control group, the cell mortality rate of the red stage in the treatment group was reduced by up to 81.6%, and the biomass and astaxanthin production was increased by 1.63 times and 2.1 times, respectively. (3) The optimal IBD was determined to be 0.5, and the highest astaxanthin content can reach 38.02 ± 2.40 mg·g−1. Thus, this work sought to give useful information that will lead to an improved understanding of the cost-effective method of cultivation of H. pluvialis for natural astaxanthin. This will be profitable for algal and medicine industry players. [ABSTRACT FROM AUTHOR]

Haematococcus pluvialis, as the best natural resource of astaxanthin, is widely used in nutraceuticals, aquaculture, and cosmetic industries. The purpose of this work was to compare the differences in astaxanthin accumulation between motile and nonmotile cells of H. pluvialis and to determine the relationship between the two cells and astaxanthin production. The experiment design was achieved by two different types of H. pluvialis cell and three different light intensities for an eight day induction period. The astaxanthin concentrations in nonmotile cell cultures were significantly increased compared to motile cell cultures. The increase of astaxanthin was closely associated with the enlargement of cell size, and the nonmotile cells were more conducive to the formation of large astaxanthin-rich cysts than motile cells. The cyst enlargement and astaxanthin accumulation of H. pluvialis were both affected by light intensity, and a general trend was that the higher the light intensity, the larger the cysts formed, and the larger the quantity of astaxanthin accumulated. In addition, the relatively low cell mortality rate in the nonmotile cell cultures indicated that the nonmotile cells have a stronger tolerance to photooxidative stress. We suggest that applying nonmotile cells as the major cell type of H. pluvialis to the induction period may help to enhance the content of astaxanthin and the stability of astaxanthin production. [ABSTRACT FROM AUTHOR]