Secondary metabolites in Cordyceps javanica with insecticidal potential.

Cordyceps javanica has been registered as a fungal insecticide in several countries. However, little is known about whether metabolic toxins are involved in the insecticidal process. In this research, we assessed the insecticidal activity of the fermentation broth of C. javanica. Myzus persicae mortality differed when exposed to the metabolized C. javanica broths at 3 days post fermentation (DPF) and 5 DPF. Comparison of the metabolic fluid at 3 DPF and 5 DPF revealed a key alkaloid, heteratisine, which was found to have insecticidal activity and acetylcholinesterase (AChE) inhibitory activity. Heteratisine has high insecticidal activity against adult M. persicae, the absolute 50% lethal concentration (LC50) was only 0.2272 mg/L. Heteratisine showed high inhibitory activity on AChE with the 50% maximal inhibitory concentration (IC50) of 76.69 µM. Molecular docking and dynamic simulations showed that heteratisine conjugation occurs at the peripheral anionic site (PAS) of the AChE of M. persicae, leading to suppression of enzyme activity. Heteratisine was rarely found in fungal metabolites, which helps us to understand the complex and elaborate insecticidal mechanism of C. javanica.

Toxicity of crude toxin protein produced by Cordyceps fumosorosea IF-1106 against Myzus persicae (Sulze).

The entomopathogenic fungus Cordyceps fumosorosea IF-1106 is a potential biocontrol agent with high pathogenicity to the aphid Myzus persicae. We extracted the crude toxin protein from a liquid culture broth of an isolated C. fumosorosea strain using the ammonium sulfate precipitation method, and its toxicity to Myzus persicae was measured by injection, oral exposure, and topical exposure. The crude toxin protein of C. fumosorosea had insecticidal activity against M. persicae. Body cavity injection and oral exposure had significantly higher insecticidal activity against adults than contact sprays. The highest cumulative corrected mortality of adults after injection was 81.85 ± 13.45 %, and the highest cumulative corrected mortality of adults after ingestion was 85.45 ± 11.88 %. The proportion of plasmatocytes in adult blood lymphocytes reached the highest at 3 days after injection and feeding, and the proportion of granulocytes was the highest at 2 days after injection and feeding. These data confirmed the toxicity of the crude toxin protein of C. fumosorosea toxin to M. persicae and helped clarify the pathogenic mechanism of the strain. Population management of M. persicae may be possible by using a natural toxic compound produced by C. fumosorosea that is selective to this pest species.

Pathogenicity of Isaria fumosorosea to Bemisia tabaci, with some observations on the fungal infection process and host immune response.

Isaria fumosorosea is an important pathogen of whiteflies, and is used as a mycoinsecticide against this pest in many regions of the world. We quantified the pathogenicity of the Chinese isolate IF-1106 against different life stages of sweetpotato whitefly, Bemisia tabaci, on cucumber plants, and describe the infection process and aspects of the host immunological response in the laboratory. The second instar was the most susceptible life stage to infection, with mortality rates at 10(7)conidia/ml ≈83% after 7d. Scanning electron microscopy was used to monitor morphological aspects of the infection process. The following stages were observed; conidia adhered on the cuticle of B. tabaci and began to germinate within 6h of inoculation, appressoria development after 24h, germ tube penetration within 48h, emergent hyphae within 72h, secondary conidiogenesis within 96h with mass hyphal proliferation occurring on cadavers within 120h. The activities of endogenous enzymes were evaluated from host homogenate at various intervals post infection. Three enzymes associated with antioxidant activity [superoxide dismutase (SOD), perioxidase (POD), and catalase (CAT)], and two with detoxification [glutathione S-transferase (GSTs) and carboxylesterase (CarE)] were apparently upregulated in second instars infected by I. fumosorosea. Enzyme activities reached peak values at 48-60h post infection, then decreased to significantly lower than controls in 84h as mycosis occurred. Our results provide new insights into the pathogenicity and potential physiological response of B. tabaci to this fungal isolate.

Identification, Pathogenicity, and Culture Conditions of a New Isolate of Cordyceps javanica (Hypocreales: Cordycipitaceae) From Soil.

This study decribes a highly effective insecticidal isolate of Cordyceps javanica (Frieder. & Bally) (Hypocreales: Cordycipitaceae) named IJ-tg19, which was isolated from soil. Spray bioassays were performed with IJ-tg19 on Myzus persicae (Sulzer) (Hemiptera: Aphididae) adults, third-instar nymphs of Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae), and third-instar larvae of Plutella xylostella (Linnaeus) (Lepidoptera: Plutellidae) to determine the pathogenicity of the isolate. The corrected mortality rates for all three pests were 100% when the conidia concentration was 1 × 106 conidia/ml, the lowest concentration in this study, and the median survival times (MST) were 4, 4, and 3 d. The MST shortens with increasing conidia concentration. The effects of laboratory culture conditions on the sporulation and growth of the isolate were also studied. This isolate had the greatest conidia production and fastest growth rate on malt extract agar medium at 25°C. The amount of conidia produced had positive correlation to light duration, with the highest production at 24 hr light. The growth of mycelium can adapt to a moderately alkaline environment, but the optimum conidial production occurred at the pH of 7. Our finding and research will be useful in biocontrol programs that are considering using the new isolate of C. javanica against greenhouse pests.

Recanalization in Uncut Roux-en-Y Reconstruction: An Animal Experiment and a Clinical Study.

Background: Because of the challenge of jejunal closure recanalization, uncut Roux-en-Y reconstruction remains controversial. This study aimed to investigate the incidence of recanalization after uncut Roux-en-Y reconstruction in pigs and a small number of patients. Methods: Twenty miniature pigs were subjected to distal gastrectomy and uncut Roux-en-Y reconstruction using various rows of linear staplers to block the intestine. The pigs were sacrificed, and the incidence of recanalization was investigated 1 month after the operation. From December 2018 to June 2019, 10 patients with gastric cancer who had undergone elective laparoscopy-assisted distal gastrectomy and uncut Roux-en-Y reconstruction were included in this study. The primary study outcome was recanalization of the afferent limb, demonstrated by gastrointestinal radiography 1, 3, and 6 months after surgery. Various numbers of staple lines across the afferent jejunal limb were applied for closure: 2 staple lines in 2 pigs, 4 staple lines in 6 pigs, 6 staple lines in 8 pigs, and 8 staple lines in 4 pigs. Results: Complete recanalization was detected in all 20 pigs 1 month postoperatively. Recanalization was detected in five cases (50%) by gastrointestinal radiography. Among them, 1 case of recanalization was found in the 1st month after the operation, 2 cases were found in the 3rd month, and another 2 cases were found in the 6th month. Bile reflux was detected by endoscopy in 2 patients with recanalization. Conclusions: The occurrence of afferent limb recanalization after uncut Roux-en-Y reconstruction is high, and using additional staplers alone cannot decrease the incidence of recanalization. Based on our study, uncut Roux-en-Y reconstruction is not recommended.

The Effect of Photoperiods and Light Intensity on Mating Behavior and Reproduction of Grapholita molesta (Lepidoptera: Tortricidae).

Oriental fruit moth, Grapholita molesta (Busck), is a worldwide pest and is the dominant pest of rosaceous plants in northern China. Little is known, however, about the influence of abiotic factors on the daily life history events of this economically important pest, so here we evaluated the effect of different photoperiods (L:D) (0:24; 2:22; 4:20; 6:18; 8:16; 10:14; 12:12; 14:10; 15:9 [control]; 16:8; 18:6; 20:4; 22:2; and 24:0 h) and light intensities (50, 100, 200, 300, 400, and 500 lux) on the mating behavior and reproduction of oriental fruit moth. We found that oriental fruit moth adults with an 8, 9, or 10 h scotophase showed considerably more courtship behavior than those in other photoperiod treatments. Meanwhile, male fanning and male 'crawling in a circle' behaviors significantly decreased with increasing light intensity. Neither female or male oriental fruit moth longevity nor the egg hatch rate were influenced by photoperiod (P = 0.146; 0.271; 0.107) or light intensity (P = 0.268; 0.08; 0.123). In both photoperiod and light intensity treatments (P < 0.05), the number of eggs laid daily by females was significantly influenced by female age, decreasing with greater age. Female oriental fruit moth lifetime fecundity was influenced by photoperiod, with the 9, 10, 16, 18, and 22 h scotophase periods having higher fecundity than other treatments. Meanwhile, fecundity decreased with increasing light intensity.

Comprehensive analysis of differentially expressed circRNAs revealed a ceRNA network in pancreatic ductaladenocarcinoma.

INTRODUCTION: Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest malignancies. However, the molecular mechanisms underlying PDAC are still not completely understood. Circular RNAs (circRNAs) are a unique class of RNA formed by special loop splicing. More and more researchers have paid attention to circRNAs. MATERIAL AND METHODS: In this study, we constructed a circRNA-mediated competing endogenous RNA (ceRNA) network in PDAC. Gene ontology (GO) analysis was performed to explore circRNAs' potential roles in PDAC progression. We also constructed an up-stream transcriptional network of circRNAs' parental genes and found that many transcription factors (TFs), such as tumor protein p53 (TP53) and MYC, could regulate their expression. RESULTS: This study, which aimed to identify differentially expressed circRNAs in PDAC, suggested that circRNAs may also act as biomarkers for PDAC. We analyzed two public datasets (GSE69362 and GSE79634) to identify differentially expressed circRNAs in PDAC. Finally, we found that DExH-Box Helicase 9 (DHX9) may be a potential regulator of circRNA formation in PDAC. Genomic loci of four down-regulated circRNAs - hsa_circ_000691, hsa_circ_0049392, hsa_circ_0005203, and hsa_circ_0001626 - contained DHX9 binding sites, suggesting that they may be directly regulated by DHX9. CONCLUSIONS: Our study identified differentially expressed circRNAs in PDAC, suggesting that circRNAs may also act as biomarkers for PDAC. Additional investigations of function and up-stream regulation of differentially expressed circRNA in PDAC are still needed.

miR-23a acts as an oncogene in pancreatic carcinoma by targeting FOXP2.

MicroRNAs have been reported to play an important role in tumor development and progression by targeting oncogenes and tumor suppressors. miR-23a has been described as significantly upregulated in multiple cancers and involved in tumorigenesis. The aim of this study was to evaluate the potential roles of miR-23a in pancreatic ductal adenocarcinoma (PDAC). We found that miR-23a level was significantly increased in tissues of PDAC compared with that in the control by real-time PCR. FOXP2 expression was downregulated and inversely correlated with miR-23a. miR-23a directly targeted the 3'-untranslated region of FOXP2 mRNA and repressed its expression. Mechanistically, enhancement of miR-23a by transfection with mimics in Aspc-1 cells significantly promoted cell proliferation and invasion, while miR-23a inhibitors transfection in SW1990 cells induced an inhibitory effect. Moreover, restoration of FOXP2 impaired the pro-proliferation and proinvasion effects of miR-23a, indicating FOXP2 is a direct mediator of miR-23a functions. In conclusion, our findings suggest a novel miR-23a/FOXP2 link contributing to PDAC development and invasion. It may be a potential diagnostic and therapeutic target for PDAC.