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Hemocytes are pivotal in the immune response of insects against invasive pathogens. However, our knowledge of hemocyte types and their specific function in Tribolium castaneum, an increasingly important Coleoptera model insect in various research fields, remains limited. Presently, a combination of morphological criteria and dye‐staining properties were used to characterize hemocyte types from T. castaneum larvae, and 4 distinct types were identified: granulocytes, oenocytoids, plasmatocytes and prohemocytes. Following different immune challenges, the total hemocyte counts declined rapidly in the initial phase (at 2 h), then increased over time (at 4 and 6 h) and eventually returned to the naive state by 24 h post‐injection. Notably, the morphology of granulocytes underwent dramatic changes, characterized by an expansion of the surface area and an increased production of pseudopods, and with the number of granulocytes rising significantly through mitotic division. Granulocytes and plasmatocytes, the main hemocyte types in T. castaneum larvae, can phagocytose bacteria or latex beads injected into the larval hemolymph in vivo. Furthermore, these hemocytes participate in the encapsulation and melanization processes in vitro, forming capsules to encapsulate and melanize nickel–nitrilotriacetic acid (Ni–NTA) beads. This study provides the first comprehensive characterization of circulating hemocytes in T. castaneum larvae, offering valuable insights into cell‐mediated immunity in response to bacterial infection and the injection of latex beads. These results deepen our understanding of the cellular response mechanisms in T. castaneum larvae and lay a solid foundation for subsequent investigations of the involvement of T. castaneum hemocytes in combating pathogens. [ABSTRACT FROM AUTHOR]

Evidence is accumulating that pattern recognition receptor (PRR) C‐type lectins (CTL) play essential roles in recognition of pathogens. TcCTL14 (accession no. TC00871) contains the most domains among all CTL of Tribolium castaneum. Yet the biological function of TcCTL14 remains unclear. In this study, TcCTL14 exhibiting typical motif and domain of CTL was cloned from T. castaneum. The expression pattern analysis showed that TcCTL14 was highly expressed in late pupae and central nervous system, and was upregulated after treatment with Escherichia coli and Staphylococcus aureus, respectively. Analysis of binding affinity revealed that recombinant TcCTL14 not only could bind to lipopolysaccharide and peptidoglycan in a dose‐dependent fashion, but possibly could bind to and agglutinate different bacteria in a Ca2+‐dependent fashion. Knockdown of TcCTL14 before injection with bacteria led to the downregulation of nuclear factor‐κB transcription factors of Toll/IMD and 4 antimicrobial peptides. Knockdown of TcCTL14 also caused suppressed metamorphosis, reduced fecundity, and delayed embryogenesis of T. castaneum. Further observation discovered that knockdown of TcCTL14 inhibited the development of ovaries and embryos. The detection of signaling pathways revealed that TcCTL14 may be involved in metamorphosis and fecundity by impacting 20‐hydroxyecdysone and vitellogenin, respectively. Overall, these results indicate that TcCTL14 may contribute to immune response by agglutination or regulating the expression of antimicrobial peptides by the Toll/IMD pathway, and is required for T. castaneum development including metamorphosis, fecundity, and embryogenesis. These findings will improve the functional cognition of PRR CTL in insects and provide the new strategy for pest control. [ABSTRACT FROM AUTHOR]

Numerous physiological processes in insects are tightly regulated by neuropeptides and their receptors. Although they form an ancient signaling system, there is still a great deal of variety in neuropeptides and their receptors among different species within the same order. Neuropeptides and their receptors have been documented in many hemipteran insects, but the differences among them have been poorly characterized. Commercial grapevines worldwide are plagued by the bug Daktulosphaira vitifoliae (Hemiptera: Sternorrhyncha). Here, 33 neuropeptide precursors and 48 putative neuropeptide G protein‐coupled receptor (GPCR) genes were identified in D. vitifoliae. Their expression profiles at the probe and feeding stages reflected potential regulatory roles in probe behavior. By comparison, we found that the Releasing Hormone‐Related Peptides (GnRHs) system of Sternorrhyncha was differentiated from those of the other 2 suborders in Hemiptera. Independent secondary losses of the adipokinetic hormone/corazonin‐related peptide receptor (ACP) and corazonin (CRZ) occurred during the evolution of Sternorrhyncha. Additionally, we discovered that the neuropeptide signaling systems of Sternorrhyncha were very different from those of Heteroptera and Auchenorrhyncha, which was consistent with Sternorrhyncha's phylogenetic position at the base of the order. This research provides more knowledge on neuropeptide systems and sets the groundwork for the creation of novel D. vitifoliae management strategies that specifically target these signaling pathways. [ABSTRACT FROM AUTHOR]

The glass transition temperature ( T g ) is a crucial characteristic of polyimides (PIs). Developing a T g predictive model using machine learning methodologies can facilitate the design of PI structures and expedite the development process. In this investigation, a data set comprising 1257 PIs was assembled, with T g values determined using differential scanning calorimetry. 210 molecular descriptors were computed using RDKit, and subsequently, six distinct feature selection methodologies were employed to refine the descriptor set. Quantitative structure-property relationship models targeting T g ( T g -QSPR) were then constructed using five ensemble learning algorithms and one deep learning algorithm. These models exhibited high predictive accuracy and robustness, with the CATBoost model demonstrating the highest accuracy, achieving a coefficient of determination of 0.823 for the test set, a mean absolute error of 20.1 °C, and a root-mean-square error of 29.0 °C. The study identified the NumRotatableBonds descriptor as particularly influential on T g , showing a negative correlation with the property. Additionally, the model's accuracy was validated using ten new PI films not included in the original data set, resulting in absolute errors ranging from 2.5 to 26.9 °C and absolute percentage error rates of 1.0-12.8%. These findings underscore the importance of utilizing extensive and diverse data sets for predictive modeling to enhance accuracy and stability. Furthermore, exploring the interpretability of the model and experimentally validating newly synthesized PIs have augmented the practical utility of the model. Under the guidance of the T g -QSPR models, it will be possible to accelerate the performance prediction and structural design of PIs in the future.

Background: The treatment of diabetes with plant ingredients such as in Traditional Chinese Medicine (TCM) is an alternative to classical chemotherapy., Objective: This study aims to explore the hypoglycemic effect of Trichosanthes pericarpium powder (TP) and intestinal bacteria transplantation in type 2 diabetic mice. The relationship between intestinal bacteria transplantation and improvement in insulin resistance was also investigated., Methods: The polyphenols and terpenoids in the TP were identified by LC-MS/MS. Streptozotocin was used to induce a mouse model of type 2 diabetes. Diabetic mice were treated with different doses of TP and the intestinal bacteria obtained from the high-dose TP group for four weeks., Results: As a result, FBG levels were found to be significantly reduced in diabetic mice, weight gain and organ enlargement were alleviated, and insulin resistance was significantly improved. TP administration also improved the disorder in intestinal bacteria in diabetic mice. Besides, TP can increase the liver AMPK, SIRT1, GLUT1, and GLUT4 gene expression, while down-regulated PEPCK and G6Pase gene expression suggest a potential mechanism for hypoglycemia in diabetic mice., Conclusion: Oral administration of Trichosanthes pericarpium powder in the treatment of diabetes may be achieved by restoring hepatic function, improving insulin resistance, and the dynamic balance of intestinal bacteria., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)