Distinct Responses of Thitarodes xiaojinensis ß-1,3-Glucan Recognition Protein-1 and Immulectin-8 to Ophiocordyceps sinensis and Cordyceps militaris Infection.

Melanization and encapsulation are prominent defense responses against microbes detected by pattern recognition receptors of their host insects. In the ghost moth Thitarodes xiaojinensis, an activated immune system can melanize and encapsulate the fungus Cordyceps militaris However, these responses were hardly detected in the host hemolymph postinfection of another fungus Ophiocordyceps sinensis The immune interaction between O. sinensis and the host remains largely unknown, which hinders the artificial cultivation of Chinese cordyceps. We found that T. xiaojinensis ß-1,3-glucan recognition protein-1 (ßGRP1) was needed for prophenoloxidase activation induced by C. militaris Failure of ßGRP1 to recognize O. sinensis is a primary reason for the lack of melanization in the infected host. Lyticase or snailase treatment combined with binding and immunofluorescence detection showed the existence of a protective layer preventing the fungus from ßGRP1 recognition. Coimmunoprecipitation and mass spectrometry analysis indicated that ßGRP1 interacted with immulectin-8 (IML8) via binding to C. militaris IML8 promotes encapsulation. This study suggests the roles of T. xiaojinensis ßGRP1 and IML8 in modulating immune responses against C. militaris Most importantly, the data indicate that O. sinensis may evade melanization by preventing ßGRP1 recognition.

Shifting species interaction in soil microbial community and its influence on ecosystem functions modulating.

The supportive and negative evidence for the stress gradient hypothesis (SGH) led to an ongoing debate among ecologists and called for new empirical and theoretical work. In this study, we took various biological soil crust (BSCs) samples along a spatial gradient with four environmental stress levels to examine the fitness of SGH in microbial interactions and evaluate its influence on biodiversity-function relationships in BSCs. A new assessment method of species interactions within hard-cultured invisible soil community was employed, directly based on denaturing gradient gel electrophoresis fingerprint images. The results showed that biotic interactions in soil phototroph community dramatically shifted from facilitation to dominant competition with the improvement of microhabitats. It offered new evidence, which presented a different perspective on the hypothesis that the relative importance of facilitation and competition varies inversely along the gradient of abiotic stress. The path analysis indicated that influence of biotic interactions (r = 0.19, p < 0.05) on ecosystem functions is lower than other community properties (r = 0.62, p < 0.001), including soil moisture, crust coverage, and biodiversity. Furthermore, the correlation between species interactions and community properties was non-significant with low negative influence (r = -0.27, p > 0.05). We demonstrate that the inversion of biotic interaction as a response to the gradient of abiotic stresses existed not only in the visible plant community but also in the soil microbial community.

Development and validation of a risk prediction model for breast cancer-related lymphedema in postoperative patients with breast cancer.

OBJECTIVE: Breast cancer-related lymphedema (BCRL) is a common post-operative complication in patients with breast cancer. Here, we sought to develop and validate a predictive model of BCRL in Chinese patients with breast cancer. METHODS: Clinical and demographic data on patients with breast cancer were collected between 2016 and 2021 at a Cancer Hospital in China. A nomogram for predicting the risk of lymphedema in postoperative patients with breast cancer was constructed and verified using R 3.5.2 software. Model performance was evaluated using area under the ROC curve (AUC) and goodness-of-fit statistics, and the model was internally validated. RESULTS: A total of 1732 postoperative patients with breast cancer, comprising 1212 and 520 patients in the development and validation groups, respectively, were included. Of these 438 (25.39%) developed lymphedema. Significant predictors identified in the predictive model were time since breast cancer surgery, level of lymph node dissection, number of lymph nodes dissected, radiotherapy, and postoperative body mass index. At the 31.9% optimal cut-off the model had AUC values of 0.728 and 0.710 in the development and validation groups, respectively. Calibration plots showed a good match between predicted and observed rates. In decision curve analysis, the net benefit of the model was better between threshold probabilities of 10%-80%. CONCLUSION: The model has good discrimination and accuracy for lymphedema risk assessment, which can provide a reference for individualized clinical prediction of the risk of BCRL. Multicenter prospective trials are required to verify the predictive value of the model.

[Effect of acteoside on learning and memory impairment induced by scopolamine in mice].

OBJECTIVE: To study on the effect of acteoside on learning and memory of dementia mice. METHOD: Mice were orally administered with acteoside for 10 days. Scopolamine was used to establish the acquired learning disability in mice. Their learning and memory were detected with a behavioral experiment (step-down test). After the behavior test, corticocerebral and hippocampus tissues of mice were detected with biochemical indexes, including GSH-Px, T-SOD, MDA, TChE and contents of protein in brain tissues. RESULT: Mice were administered with acteoside for 10 d in advance to alleviate the acquired learning disability induced by scopolamine. Compared with the model group, acteoside increased the latency period in the step-down test and reduced error times. Besides, acteoside increased the activity of GSH-Px, T-SOD, TChE and protein content in their brain tissues, but decreased MDA content. CONCLUSION: Acteoside can significantly alleviate the acquired learning disability in mice induced by scopolamine. Its mechanism may be related with its effect of inhibiting the generation of free radicals in mice and improving the function of the central cholinergic system.

[Pharmacokinetic study on acetoside in rats].

OBJECTIVE: To establish a HPLC method for determining acetoside in rat plasma and to investigate the pharmacokinetic characteristics of acetoside in rats. METHOD: Six rats were orally administered with 150 mg x kg(-1) acetoside and their blood samples were collected at different time points. The plasma concentration of acetoside was determined by reserved HPLC, and the pharmacokinetic parameters were calculated by DAS 2.0 software. RESULT: The regression equation of acetoside in rats plasma was Y = 3.509 8X-0.096 8 (r = 0.996 8), which showed a good linear relation at 0.125-2.5 mg x L(-1). The method showed a recovery of more than 85%, and both inter-day and intra-day RSDs were less than 15%. After the oral administration of 150 mg x kg(-1) acetoside, the concentration-time curves of acetoside were expressed in a open two-compartment model. The main pharmacokinetics parameters of T(max), C(max), t(1/2alpha), t(1/2beta), AUC(0-t), AUC(0-infinity), CL/F, V/F and K(a) were respectively 0.36 h, 1.126 mg x L(-1), 0.759, 4.842 h, 3.134, 3.766 mg x h x L(-), 87.089 L x h(t) x kg(-1), 207.704 L x kg(-1) and 6.345 h(-1) respectively. CONCLUSION: It is first time to establish such a HPLC method to determine the concentration of acetoside in plasma. The method is so highly specified and sensitive that it can ble used in quantitative analysis in vivo on acetoside.

Immulectin-2 from the ghost moth, Thitarodes xiaojinensis (Lepidoptera: Hepialidae), modulates cellular and humoral responses against fungal infection.

C type-lectins constitute a large family of pattern recognition receptors, playing important roles in insect immune defenses. Thitarodes xiaojinensis larvae showed distinct immune features after Ophiocordyceps sinensis, Cordyceps militaris, or Beauveria bassiana infection. Based on transcriptome and immunoblot analysis, we found that immulectin-2 (IML2) was induced after T. xiaojinensis larvae were infected by C. militaris or B. bassiana but maintained at a low level after larvae injected with O. sinensis or Ringer's buffer. Recombinant IML2 (rIML2) could promote melanization, encapsulation, phagocytosis, and hemocyte aggregation in vitro. RNA interference with IML2 induced a significant reduction in the transcript levels of various antimicrobial peptides. Importantly, we found that the abundance of O. sinensis blastospores coated with rIML2 dramatically decreased in the host hemolymph. Overall, this study demonstrated that T. xiaojinensis IML2 modulates cellular and humoral responses to entomopathogenic fungi, broadening our view of the immune interaction between O. sinensis and its host.

Necroptosis Mediates Cigarette Smoke-Induced Inflammatory Responses in Macrophages.

Introduction: Cigarette smoke (CS)-induced inflammation in macrophages is involved in the pathological process of chronic obstructive pulmonary disease (COPD). Necroptosis, which is a form of programmed necrosis, has a close relationship with robust inflammation, while its roles in COPD are unclear. Materials and Methods: Necroptosis markers were measured in mouse alveolar macrophages and cultured bone marrow-derived macrophages (BMDMs). Necroptosis inhibitors were used to block necroptosis in BMDMs, and inflammatory cytokines were detected. We further explored the related signaling pathways. Results: In this study, we demonstrated the way in which necroptosis, in addition to its upstream and downstream signals, regulates CS-induced inflammatory responses in macrophages. We observed that CS exposure caused a significant increase in the levels of necroptosis markers (receptor interacting kinases [RIPK] 1 and 3) in mouse alveolar macrophages and BMDMs. Pharmacological inhibition of RIPK1 or 3 caused a significant suppression in CS extract (CSE)-induced inflammatory cytokines, chemokine ligands (CXCL) 1 and 2, and interleukin (IL)-6 in BMDMs. CSE-induced necroptosis was regulated by mitochondrial reactive oxygen species (mitoROS), which also promoted inflammation in BMDMs. Furthermore, necroptosis regulated CSE-induced inflammatory responses in BMDMs, most likely through activation of the nuclear factor-κB pathway. Conclusion: Taken together, our results demonstrate that mitoROS-dependent necroptosis is essential for CS-induced inflammation in BMDMs and suggest that inhibition of necroptosis in macrophages may represent effective therapeutic approaches for COPD patients.

[Role of amino acid residues at positions 322 and 329 of hemagglutinin in virulence of H5N1 avian influenza virus].

Two H5N1 avian influenza viruses (AIV), A/mallard/Huadong/S/2005 (S, IVPI = 2.65, in mallard) and A/mallard/Huadong/Y/2003 (Y, IVPI = 0, in mallard), were capable of distinct in pathogenicity to non-immunized mallards (Anas platyrhynchos). There were two amino acid residues difference in the HA cleavage site between two viruses, 322 (S, Leu; Y, Gln) and 329 (S, deletion; Y, Lys). Based on the variation, a series of recombinant viruses carrying HA gene either from S or Y virus with mutation at 322 and/or 329 were constructed via reverse genetics system to explore the influence of the two amino acid residues on viral pathogenicity in mallards. Recombinant viruses with S virus backbone were completely attenuated in terms of their virulence to ducks when position 322 (L322Q) and/or position 329 (-329K) of HA gene had been mutated. The critical role that L322 and -329 of HA protein from S virus play in the high virulence to ducks were influenced by the entire background of that protein because the recombinant virus with HA gene from Y and other seven genes from S were completely attenuated even if Q322L and K329- mutations of HA gene had been achieved. Recombinant viruses with Y virus backbone significantly increased their virulence to ducks when position 322 (Q322L) and/or position 329 (K329-) of HA gene had been mutated. All recombinant viruses carrying HA gene from Y with Q322L and/or K329-mutations and other seven genes from S were completely attenuated in terms of virulence to ducks whereas all recombinant viruses carrying HA gene from Y with same mutations and other seven genes from Y gained significant virulence. It seems that the compatibility among eight genes might be an important factor for HA to exert its functions. Results indicated that the mutation at amino acid position 322 and deletion at 329 in HA cleavage site significantly influence the pathogenicity of S and Y viruses in mallard, the compatibility among eight genes also contribute to the pathogenicity of both viruses in mallard.