Juvenile Hormone Involved in the Defensive Behaviors of Soldiers in Termite Reticulitermes aculabialis.

Eusocial insects have evolved specific defensive strategies to protect their colonies. In termite colonies, soldiers perform a colony-level defense by displaying mechanical biting, head-banging and mandible opening-closing behaviors. However, few studies have been reported on the factors modulating defensive behaviors in termites. Owing to JH (juvenile hormone) being involved in soldier differentiation, JH was speculated to affect defensive behaviors in termite soldiers. To determine the effect of JH on the defensive behaviors of termite soldiers, we performed a JHA-feeding and RaSsp1-silencing experiment and then tested the changes in defense-related behaviors, alarm pheromones and key JH signaling genes. The observed result was that after feeding workers with JHA, soldiers displayed the following: (1) decreased biting events and increased head-banging events; (2) a reduced expression of RaSsp1 and increased expression of Met (methoprene-tolerant, the nuclear receptor of JH) and Kr-h1 (the JH-inducible transcription factor Krüppel homolog 1); and (3) a decreased concentration of alarm pheromones, including α-pinene, ß-pinene and limonene (+, -). Further study showed that soldiers silenced for RaSsp1 also exhibited (1) decreased biting events and increased head-banging events and (2) increased expression of Met and Kr-h1. In addition, soldiers stimulated by the alarm pheromone limonene displayed an increase in the frequency of mandible opening-closing and biting behavior. All of these results show that JHA influenced the defensive behaviors of termite soldiers, possibly via downregulating RaSsp1 expression, up-regulating Met and Kr-h1 and stimulating the secretion of alarm pheromones, suggesting that the JH pathway plays important roles in modulating social behaviors in termite colonies.

Soldier Caste-Specific Protein 1 Is Involved in Soldier Differentiation in Termite Reticulitermes aculabialis.

Termite soldiers are a unique caste among social insects, and their differentiation can be induced by Juvenile hormone (JH) from workers through two molts (worker-presoldier-soldier). However, the molecular mechanism underlying the worker-to-soldier transformation in termites is poorly understood. To explore the mechanism of soldier differentiation induced by JH, the gene soldier caste-specific protein 1 (RaSsp1, NCBI accession no: MT861054.1) in R. aculabialis was cloned, and its function was studied. This gene was highly expressed in the soldier caste, and the protein RsSsp1 was similar to the JHBP (JH-binding protein) domain-containing protein by Predict Protein online. In addition, JHIII could be anchored in the hydrophobic cage of RaSsp1 as the epoxide of the JHBP-bound JH according to the protein ligand molecular docking online tool AutoDock. The functional studies indicated that knocking down of the RaSsp1 shorted the presoldier's head capsule, reduced mandible size, delayed molting time and decreased molting rate (from worker to presoldier) at the beginning of worker gut-purging. Furthermore, knocking down of the RaSsp1 had a more pronounced effect on soldier differentiation (from presoldier to soldier), and manifested in significantly shorter mandibles, rounder head capsules, and lower molting rate (from worker to presoldier) at the beginning of presoldier gut-purging. Correspondingly, the expressions of JH receptor Methoprene-tolerant (Met), the JH-inducible transcription factor Krüppel homolog1 (Kr-h1) and ecdysone signal genes Broad-complex (Br-C) were downregulated when knocking down the RaSsp1 at the above two stages. All these results that RaSsp1 may be involved in soldier differentiation from workers by binding and transporting JH.

Preparation and In Vitro Evaluation of a Nano Ultrasound Contrast Agent Targeting Pancreatic Cancer.

To prepare a nano-sized ultrasound contrast agent that specifically targets pancreatic cancer cells and to evaluate its targeting effect In Vitro. PLGA-PEG-NHS was synthesized using PLGA, NHS, and PEG and detected using 1H-NMR. PLGA-PEG-NHS and PFOB were used to prepare PLGA nano contrast agent coated with PFOB by emulsification and volatilization, and then a hedgehog antibody was conjugated. The morphology of the nano contrast agent was observed using a transmission electron microscope, and its particle size and potential were measured using the dynamic light scattering method. The entrapment and drug loading efficiency of the nano contrast agent was measured using gas chromatography-mass spectrometry. The In Vitro release characteristics of the nano contrast agent was measured using the dialysis method. Human pancreatic cancer cell lines SW1990 and CFPAC1 were cultured in medium containing the nano contrast agent. The targeting ability of the nano contrast agent was qualitatively and quantitatively verified using fluorescence microscopy and flow cytometry. The average particle size of the targeted ultrasound contrast agent was 198.9 nm, zeta potential was -31.8 mv, entrapment rate was 63.7±3.9%, drug loading efficiency was 14.3±0.9%, and drug release was 85.3% in 48 h. In Vitro cell experiments showed that the targeted ultrasound contrast agent strongly bound to SW1990 cells with high expression of hedgehog antigen, but no specific binding was detected in CFPAC-1 cells which lack the hedgehog antigen. The nano ultrasound contrast agent prepared by emulsification and volatilization method can be potentially used for the diagnosis of pancreatic cancer.

[A case report of multiple dentigerous cyst of mandible and review of literature].

Dentigerous cyst belongs to one kind of odontogenic cysts, and is also known as follicular cyst. After the formation of the crown or root of the tooth, liquid exudates between the residual enamel epithelium and the crown surface to form odontogenic cysts. Multiple odontogenic cysts are rare in the oral and maxillofacial regions, especially in different areas of the jaw. In this paper, we reported case with multiple odontogenic cysts and discussed its etiology,pathological classification,differential diagnosis and treatment.