Crucial roles of specialized chitinases in elytral and hindwing cuticles construction in Leptinotarsa decemlineata.

BACKGROUND: The Colorado potato beetle (CPB), Leptinotarsa decemlineata, is a major potato (Solanum tuberosum) pest, infesting over 16 million km2 and causing substantial economic losses. The insect cuticle forms an apical extracellular matrix (ECM) envelope covering exposed organs to direct morphogenesis and confer structural protection. While select chitinase (Cht) genes have proven essential for larval development, their potential activities directing ECM remodeling underlying adult wing maturation remain undefined. RESULTS: We investigated the expression patterns and performed an oral RNA interference (RNAi) screen targeting 19 LdChts in late-instar L. decemlineata larvae. Subsequently, we assessed their effects on adult eclosion and wing characteristics. Knockdown of LdCht5, LdCht7, LdCht10, LdIDGF2, and LdIDGF4, as well as others from Group IV (LdCht15, LdCht12, LdCht17, and LdCht13) and Groups VII-X (LdCht2, LdCht11, LdCht1, and LdCht3), resulting in shrunken, misshapen elytra with reduced areal density, as well as transverse wrinkling and impaired wing-tip folding in hindwings. Scanning electron micrographs revealed eroded elytral ridges alongside thinned, ruptured hindwing veins, indicative of mechanical fragility post-LdCht suppression. Spectroscopic analysis uncovered biomolecular alterations underlying the elytral anomalies, including decreases in peaks representing chitin, proteins, and lipids. This loss of essential ECM components provides evidence for the fragility, wrinkling, and shrinkage observed in the RNAi groups. CONCLUSION: Our findings elucidate the crucial role of chitinases in the turnover of chitinous cuticles on beetle wings, offering insights into RNAi-based control strategies against this invasive pest. © 2024 Society of Chemical Industry.

Exploration of surface tension measurement methods for pharmaceutical excipients.

Surface tension is a crucial functional indicator for various classes of pharmaceutical excipients, as highlighted in both the Pharmacopoeia of the People's Republic of China (ChP) < 9601 Guidelines for Functionality-related Characteristics of Pharmaceutical Excipients > and the United States Pharmacopoeia (USP) < 1059 Excipient Performance >. However, there are few systematic studies on surface tension measurement of pharmaceutical excipients, resulting in a lack of stable parameter support in practical applications. In this study, we aim to fill this gap by exploring three different methods for measuring surface tension. These methods were carefully developed taking into account the actual measurement process and statistical theory, thus ensuring their applicability and reliability. Through comparative analyses, we have identified the most suitable measurement methods for different classes of pharmaceutical excipients. In addition, this paper describes the surface adsorption behavior of various excipients. Therefore, this study provides valuable guidance for the determination of surface tension and the study of surface adsorption behavior, which lays the foundation for further comprehensive research in the field of surface tension of pharmaceutical excipients and the improvement of general pharmacopoeia specification.

Identification of chitinase genes and roles in the larval-pupal transition of Leptinotarsa decemlineata.

BACKGROUND: Insect chitinases play crucial roles in degrading chitin in the extracellular matrix, affecting insect development and molting. However, our understanding of the specific functions of various chitinases in Leptinotarsa decemlineata is limited, hindering the deployment of novel gene-targeting technologies as pest management strategies. RESULTS: We identified and characterized 19 full-length complementary DNA (cDNA) sequences of chitinase genes (LdChts) in Leptinotarsa decemlineata. Despite having varying domain architectures, all these chitinases contained at least one chitinase catalytic domain. Phylogenetic analysis classified the chitinase proteins into ten distinct clusters (groups I-X). Expression profiles showed the highest expression in chitin-rich tissues or during specific developmental stages from the larva-to-pupa transition. Gene-specific RNA interference (RNAi) experiments provided valuable insight into chitinase gene function. Silencing of group II LdCht10 prevented larval-larval molting, larval-prepupal, and prepupal-pupal processes. Moreover, our study revealed that LdCht5, LdCht2, LdCht11, LdCht1, and LdCht3 from groups I and VII-X were specifically essential for the transition from prepupal to pupal stage, whereas LdIDGF2 from group V was necessary for the larval-prepupal metamorphic process. The chitinase gene LdCht7 from group III and LdIDGF4 from group V were involved in both the larva-to-prepupa and the prepupa-to-pupa shift. Additionally, our findings also shed light on the exclusive expression of nine chitinase genes within group IV in the digestive system, suggesting their potential role in regulating larval body weight and larva-to-pupa transition. CONCLUSION: Our results provide a comprehensive understanding of the functional specialization of chitinase genes during the molting process of various stages and identify potential targets for RNAi-based management of Leptinotarsa decemlineata. © 2023 Society of Chemical Industry.

Sericin nano-gel agglomerates mimicking the pericellular matrix induce the condensation of mesenchymal stem cells and trigger cartilage micro-tissue formation without exogenous stimulation of growth factors in vitro.

Mesenchymal stem cells (MSCs) are excellent seed cells for cartilage tissue engineering and regenerative medicine. Though the condensation of MSCs is the first step of their differentiation into chondrocytes in skeletal development, the process is a challenge in cartilage repairing by MSCs. The pericellular matrix (PCM), a distinct region surrounding the chondrocytes, acts as an extracellular linker among cells and forms the microenvironment of chondrocytes. Inspired by this, sericin nano-gel soft-agglomerates were prepared and used as linkers to induce MSCs to assemble into micro-spheres and differentiate into cartilage-like micro-tissues without exogenous stimulation of growth factors. These sericin nano-gel soft-agglomerates are composed of sericin nano-gels prepared by the chelation of metal ions and sericin protein. The MSCs cultured on 2D culture plates self-assembled into cell-microspheres centered by sericin nano-gel agglomerates. The self-assembly progress of MSCs is superior to the traditional centrifugation to achieve MSC condensation due to its facility, friendliness to MSCs and avoidance of the side-effects of growth factors. The analysis of transcriptomic results suggested that sericin nano-gel agglomerates offered a soft mechanical stimulation to MSCs similar to that of the PCM to chondrocytes and triggered some signaling pathways as associated with MSC chondrogenesis. The strategy of utilizing biomaterials to mimic the PCM as a linker and as a mechanical micro-environment and to induce cell aggregation and trigger the differentiation of MSCs can be employed to drive 3D cellular organization and micro-tissue fabrication in vitro. These cartilage micro-masses reported in this study can be potential candidates for cartilage repairing, cellular building blocks for 3D bio-printing and a model for cartilage development and drug screening.

Advances in Preparation and Properties of Regenerated Silk Fibroin.

Over the years, silk fibroin (SF) has gained significant attention in various fields, such as biomedicine, tissue engineering, food processing, photochemistry, and biosensing, owing to its remarkable biocompatibility, machinability, and chemical modifiability. The process of obtaining regenerated silk fibroin (RSF) involves degumming, dissolving, dialysis, and centrifugation. RSF can be further fabricated into films, sponges, microspheres, gels, nanofibers, and other forms. It is now understood that the dissolution method selected greatly impacts the molecular weight distribution and structure of RSF, consequently influencing its subsequent processing and application. This study comprehensively explores and summarizes different dissolution methods of SF while examining their effects on the structure and performance of RSF. The findings presented herein aim to provide valuable insights and references for researchers and practitioners interested in utilizing RSF in diverse fields.

[Evolution of auditory brainstem response in 0-6 years old normal hearing children and characteristics of children with abnormal acoustic conduction].

Objective:To explore the normal reference range of Click-ABR latency and interwave period in 0-6 years old children, and to analyze the clinical characteristics of Click-ABR in children with sound transmission function is abnormal. Methods:A total of 1791（3582 ears） normal hearing children aged 0-6 years and 176（258 ears） conductive hearing loss children were selected for Click-ABR. The differences of Click-ABR parameters in children of different months were analyzed, and the correlation between the degree of conductive hearing loss and Click-ABR parameters was explored. Results:The incubation period of wave Ⅰ was not correlated with the age of month, while the incubation period of wave Ⅲ, wave Ⅴ, waveⅠ-Ⅲ and wave Ⅰ-Ⅴ were highly correlated with the age of month. There was a positive correlation between the latency of wave Ⅰ and hearing threshold in the children with sound transmission function is abnormal under 80 dB nHL stimulation, and there was no difference between the standard values of wave Ⅰ-Ⅲ and Ⅰ-Ⅴ in the children with sound transmission function is abnormal and normal children. Conclusion:The latency of ABR wave Ⅲ and Ⅴ, and the interval between wave Ⅰ-Ⅲ and Ⅰ-Ⅴ shorten with the increase of age in children aged 0-6 years. The normal ABR values of children of different ages should be established in each hearing clinic for children as a reference. Combined with Click-ABR threshold and 80 dB nHL acoustic subwave Ⅰlatency, the abnormal conduction function can be preliminatively screened out, which should be further supplemented with other combinations of hearing diagnosis.

Auditory and verbal skills development post-cochlear implantation in Mandarin children with auditory neuropathy: a follow-up study.

BACKGROUND: Cochlear implant (CI) is commonly used as one of the interventions in auditory neuropathy (AN) children. However, there are limited studies regarding the efficiency of CI in AN children. OBJECTIVE: This study aimed to compare the auditory and verbal skills development between the AN and typically developing (TD) children with CI. METHODS: The follow-up study compared the post-CI scores of questionnaires of AN and TD children about auditory and verbal skills development at 0, 1, 2, 3, 6, 9, 12, and 18 months of CI use. RESULTS: The results of auditory perception in AN and TD groups showed a significant improvement after first 3 months. Furthermore, the score was significantly lower in AN group after 18 months of CI use. The results of verbal skills in AN group showed a progressive trend after 9 months of CI use. Besides, the scores were significantly lower in AN group after 12 months of CI use. CONCLUSION AND SIGNIFICANCE: The auditory perception development in AN children with CI was rapidly improved during first 3 months, and verbal skills showed a trend of improvement after 9 months of CI use. However, the differences in auditory and verbal skills between AN and TD groups increased over time.

Control of the pore size of honeycomb polymer film from micrometers to nanometers via substrate-temperature regulation and its application to photovoltaic and heat-resistant polymer films.

Honeycomb porous polystyrene (PS) films with an aspect ratio of pore depth to pore diameter at approximately 1.0 were fabricated using the breath figure (BF) method. Two modes of water droplet coalescence in the pore growth were observed in real-time by optical microscopy. Pore size significantly increases with the increase in humidity and the decrease in substrate temperature. The porous pattern could emerge even at room temperature under high humidity of 80%. Boiling point and solvent density significantly influence the pore distribution and pore depth. Chloroform and tetrahydrofuran achieve more uniform hexagonal patterns than benzene and dichloromethane. Subsequently, to obtain nanometer porous PS film, the fast-evaporation BF process was designed by regulating the gradient substrate temperature and evaporation time, and porous mesoscopic PS film was obtained. The minimum pore diameter and corresponding pore depth are about 120 nm and 27 nm, respectively. Finally, the fast-evaporation BF process was applied to the honeycomb film formation of photovoltaic polymer poly(3-hexylthiophene) (P3HT), and the heat-resistant polymers polysulfone (PSF) and polyimide (PI).

Novaluron ingestion causes larval lethality and inhibits chitin content in Leptinotarsa decemlineata fourth-instar larvae.

To accomplish consistent, long-term, integrated management (IPM) of the Colorado potato beetle, Leptinotarsa decemlineata (Say), research assessing the potential of novel, IPM-compatible insecticides is essential. Novaluron is a potent benzoylurea insecticide. In the present paper, we found that novaluron ingestion by the fourth-instar larvae inhibited foliage consumption, reduced larval fresh weight, and delayed development period, in a dose dependent manner. Most of the resulting larvae fail to pupate, and died at prepupae stage, with larvicidal activity comparable with those of cyhalothrin and spinosad but lower than those of fipronil and abamectin. Moreover, many surviving pupae that fed novaluron failed to emerge as adults, in a dose dependent pattern. Furthermore, feeding of novaluron significantly decreased chitin contents in body carcass (without midgut) and integument specimen, whereas the chitin concentration in the midgut peritrophic matrix was not affected. Furthermore, uridine diphosphate-N-acetylglucosamine-pyrophosphorylase gene (LdUAP1) and chitin synthase Aa (LdChSAa), which were mainly responsible for chitin biosynthesis in ectodermally-derived tissues, were surpressed and activated respectively after novaluron ingestion. Therefore, novaluron is an effective benzoylurea insecticide to L. decemlineata fourth-instar larvae. It inhibited chitin biosynthesis in ectodermally-derived tissues, disrupted ecdysis, impaired pupation and adult emergence, and led to death in juvenile life stages.

Hydrothermal formation of N/Ti3+ codoped multiphasic (brookite-anatase-rutile) TiO2 heterojunctions with enhanced visible light driven photocatalytic performance.

Mixed phased TiO2 catalysts codoped with N and Ti3+ have been successfully synthesized using a low-temperature, one step hydrothermal method using TiN as the precursor. The as prepared samples were studied for their crystalline structure, morphology, composition, and optical properties using various analytical techniques such as X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS), and X-ray photoelectron spectroscopy (XPS). It was observed that N and Ti3+ codoped TiO2 samples having mixed phases of brookite, anatase and rutile could be obtained at a wide range of hydrothermal time durations ranging from 24 h to 72 h. The as-prepared samples exhibit a distinct red shift, suggesting that N and Ti3+ codoping significantly enhances the optical absorption characteristics of TiO2. The photocatalytic activity of the prepared samples was studied using methylene blue and colorless resorcinol dyes. The prepared samples demonstrated good photocatalytic activity because of their excellent mixed phase crystalline structures and an increase in the threshold wavelength response. The mechanism of the photocatalytic degradation reaction was also studied. This work provides a novel strategy to fabricate and extend the visible light response of TiO2, which facilitates their application in the environment remediation and energy conversion.

RNA interference of chitin synthase genes inhibits chitin biosynthesis and affects larval performance in Leptinotarsa decemlineata (Say).

Dietary introduction of bacterially expressed double-stranded RNA (dsRNA) has great potential for management of Leptinotarsa decemlineata. Identification of the most attractive candidate genes for RNA interference (RNAi) is the first step. In the present paper, three complete chitin synthase cDNA sequences (LdChSAa, LdChSAb and LdChSB) were cloned. LdChSAa and LdChSAb, two splicing variants of LdChSA gene, were highly expressed in ectodermally-derived epidermal cells forming epidermis, trachea, foregut and hindgut, whereas LdChSB was mainly transcribed in midgut cells. Feeding bacterially expressed dsChSA (derived from a common fragment of LdChSAa and LdChSAb), dsChSAa, dsChSAb and dsChSB in the second- and fourth-instar larvae specifically knocked down their target mRNAs. RNAi of LdChSAa+LdChSAb and LdChSAa lowered chitin contents in whole body and integument samples, and thinned tracheal taenidia. The resulting larvae failed to ecdyse, pupate, or emerge as adults. Comparably, knockdown of LdChSAb mainly affected pupal-adult molting. The LdChSAb RNAi pupae did not completely shed the old larval exuviae, which caused failure of adult emergence. In contrast, silencing of LdChSB significantly reduced foliage consumption, decreased chitin content in midgut sample, damaged midgut peritrophic matrix, and retarded larval growth. As a result, the development of the LdChSB RNAi hypomorphs was arrested. Our data reveal that these LdChSs are among the effective candidate genes for an RNAi-based control strategy against L. decemlineata.

Physiological roles of trehalose in Leptinotarsa larvae revealed by RNA interference of trehalose-6-phosphate synthase and trehalase genes.

Trehalose is proposed to serve multiple physiological roles in insects. However, its importance remains largely unconfirmed. In the present paper, we knocked down either a trehalose biosynthesis gene (trehalose-6-phosphate synthase, LdTPS) or each of three degradation genes (soluble trehalases LdTRE1a, LdTRE1b or membrane-bound LdTRE2) in Leptinotarsa decemlineata by RNA interference (RNAi). Knockdown of LdTPS decreased trehalose content and caused larval and pupal lethality. The LdTPS RNAi survivors consumed a greater amount of foliage, obtained a heavier body mass, accumulated more glycogen, lipid and proline, and had a smaller amount of chitin compared with the controls. Ingestion of trehalose but not glucose rescued the food consumption increase and larval mass rise, increased survivorship, and recovered glycogen, lipid and chitin to the normal levels. In contrast, silencing of LdTRE1a increased trehalose content and resulted in larval and pupal lethality. The surviving LdTRE1a RNAi hypomorphs fed a smaller quantity of food, had a lighter body weight, depleted lipid and several glucogenic amino acids, and contained a smaller amount of chitin. Neither trehalose nor glucose ingestion rescued these LdTRE1a RNAi defects. Silencing of LdTRE1b caused little effects. Knockdown of LdTRE2 caused larval death, increased trehalose contents in several tissues and diminished glycogen in the brain-corpora cardiaca-corpora allata complex (BCC). Feeding glucose but not trehalose partially rescued the high mortality rate and recovered glycogen content in the BCC. It seems that trehalose is involved in feeding regulation, sugar absorption, brain energy supply and chitin biosynthesis in L. decemlineata larvae.

IDENTIFICATION AND HORMONE INDUCTION OF PUTATIVE CHITIN SYNTHASE GENES AND SPLICE VARIANTS IN Leptinotarsa decemlineata (SAY).

Chitin synthase (ChS) plays a critical role in chitin synthesis and excretion. In this study, two ChS genes (LdChSA and LdChSB) were identified in Leptinotarsa decemlineata. LdChSA contains two splicing variants, LdChSAa and LdChSAb. Within the first, second, and third larval instars, the mRNA levels of LdChSAa, LdChSAb, and LdChSB coincide with the peaks of circulating 20-hydroxyecdysone (20E) and juvenile hormone (JH). In vitro culture of midguts and an in vivo bioassay revealed that 20E and an ecdysteroid agonist halofenozide stimulated the expression of the three LdChSs. Conversely, a reduction of 20E by RNA interference (RNAi) of an ecdysteroidogenesis gene LdSHD repressed the expression of these LdChSs, and ingestion of halofenozide by LdSHD RNAi larvae rescued the repression. Moreover, disruption of 20E signaling by RNAi of LdEcR, LdE75, LdHR3, and LdFTZ-F1 reduced the expression levels of these genes. Similarly, in vitro culture and an in vivo bioassay showed that exogenous JH and a JH analog methoprene activated the expression of the three LdChSs, whereas a decrease in JH by RNAi of a JH biosynthesis gene LdJHAMT downregulated these LdChSs. It seems that JH upregulates LdChSs at the early stage of each instar, whereas a 20E pulse triggers the transcription of LdChSs during molting in L. decemlineata.

Two Leptinotarsa uridine diphosphate N-acetylglucosamine pyrophosphorylases are specialized for chitin synthesis in larval epidermal cuticle and midgut peritrophic matrix.

Uridine diphosphate-N-acetylglucosamine-pyrophosphorylase (UAP) is involved in the biosynthesis of chitin, an essential component of the epidermal cuticle and midgut peritrophic matrix (PM) in insects. In the present paper, two putative LdUAP genes were cloned in Leptinotarsa decemlineata. In vivo bioassay revealed that 20-hydroxyecdysone (20E) and an ecdysteroid agonist halofenozide activated the expression of the two LdUAPs, whereas a decrease in 20E by RNA interference (RNAi) of an ecdysteroidogenesis gene LdSHD and a 20E signaling gene LdFTZ-F1 repressed the expression. Juvenile hormone (JH), a JH analog pyriproxyfen and an increase in JH by RNAi of an allatostatin gene LdAS-C downregulated LdUAP1 but upregulated LdUAP2, whereas a decrease in JH by silencing of a JH biosynthesis gene LdJHAMT had converse effects. Thus, expression of LdUAPs responded to both 20E and JH. Moreover, knockdown of LdUAP1 reduced chitin contents in whole larvae and integument samples, thinned tracheal taenidia, impaired larval-larval molt, larval-pupal ecdysis and adult emergence. In contrast, silencing of LdUAP2 significantly reduced foliage consumption, decreased chitin content in midgut samples, damaged PM, and retarded larval growth. The resulting larvae had lighter fresh weights, smaller body sizes and depleted fat body. As a result, the development was arrested. Combined knockdown of LdUAP1 and LdUAP2 caused an additive negative effect. Our data suggest that LdUAP1 and LdUAP2 have specialized functions in biosynthesizing chitin in the epidermal cuticle and PM respectively in L. decemlineata.

A Combination of Targeted Sunitinib Liposomes and Targeted Vinorelbine Liposomes for Treating Invasive Breast Cancer.

Regular chemotherapy cannot eradicate invasive breast cancer cells and the residual cancer cells will form vasculogenic mimicry (VM) channels under hypoxic conditions to provide nutrients for cancer masses prior to angiogenesis. This phenomenon is a major reason for the recurrence of invasive breast cancer after treatment. In this study, a novel type of targeted liposomes was developed by modifying a mitochondria-tropic material, D-a-tocopheryl polyethylene glycol 1000 succinate- triphenylphosphine conjugate (TPGS1000-TPP), to encapsulate sunitinib and vinorelbine separately and a combination of the two targeted drug liposomes was used to treat invasive breast cancer as well as VM channels. Evaluations were performed in breast cancer MCF-7 cells and highly invasive breast cancer MDA-MB-435S cells in vitro and in mice. The results determined that the functional material (TPGS1000-TPP) and suitable size of the liposomes (90-100 nm) resulted in prolonged blood circulation, an enhanced permeability retention (EPR) effect in cancer tissue, and a mitochondrial targeting effect. Targeted drug liposomes were internalized via cellular uptake and accumulated in the mitochondria of invasive breast cancer cells or VM channel-forming cancer cells to induce acute cytotoxic injury and apoptosis. Activated apoptotic enzymes caspase 9 and caspase 3 as well as down-regulated VM channel-forming indicators (MMP-9, EphA2, VE-Cadherin, FAK and HIF-1α) contributed to significantly enhanced efficacy. Therefore, a combination of targeted sunitinib liposomes and targeted vinorelbine liposomes may provide an effective strategy for treating invasive breast cancer and prevent relapse arising from VM channels.

Targeting Epirubicin Plus Quinacrine Liposomes Modified with DSPE-PEG2000-C(RGDfK) Conjugate for Eliminating Invasive Breast Cancer.

Recurrence of invasive breast cancer could arise from the residual cancer cells after comprehensive treatment. It is possible that residual invasive cancer cells are capable of forming highly patterned vasculogenic mimicry (VM) channels, leading to relapse and metastasis. In the present study, a new type of targeting epirubicin plus quinacrine liposomes was developed by modifying functional DSPE-PEG2000 with C(RGDfK), a cyclic peptide containing Arg-Gly-Asp. These liposomes could potentially eliminate invasive breast cancer and destroy VM channels. Evaluations were made in human invasive breast cancer cells and their xenografts in nude mice. The results showed that the targeting epirubicin plus quinacrine liposomes could enhance the accumulation and uptake of the drugs in cancer tissues, kill cancer cells directly, activate apoptotic enzymes, destroy the VM channels and downregulate the VM channel-forming marker molecules (EphA2, FAK, PI3K, MMP 9, MMP 14, VE-Cad and HIF-α), thereby exhibiting a strong overall anticancer efficacy. The targeting epirubicin plus quinacrine liposomes provided a promising strategy to treat invasive breast cancer and to prevent the relapse arising from VM channels after chemotherapy.

Functions of nuclear receptor HR3 during larval-pupal molting in Leptinotarsa decemlineata (Say) revealed by in vivo RNA interference.

Our previous results revealed that RNA interference-aided knockdown of Leptinotarsa decemlineata FTZ-F1 (LdFTZ-F1) reduced 20E titer, and impaired pupation. In this study, we characterized a putative LdHR3 gene, an early-late 20E-response gene upstream of LdFTZ-F1. Within the first, second and third larval instars, three expression peaks of LdHR3 occurred just before the molt. In the fourth (final) larval instar 80 h after ecdysis and prepupal stage 3 days after burying into soil, two LdHR3 peaks occurred. The LdHR3 expression peaks coincide with the peaks of circulating 20E level. In vitro midgut culture and in vivo bioassay revealed that 20E and an ecdysteroid agonist halofenozide (Hal) enhanced LdHR3 expression in the final larval instars. Conversely, a decrease in 20E by feeding a double-stranded RNA (dsRNA) against an ecdysteroidogenesis gene Ldshd repressed the expression. Moreover, Hal rescued the transcript levels in the Ldshd-silenced larvae. Thus, 20E peaks activate the expression of LdHR3. Furthermore, ingesting dsRNA against LdHR3 successfully knocked down the target gene, and impaired pupation. Finally, knockdown of LdHR3 upregulated the transcription of three ecdysteroidogenesis genes (Ldphm, Lddib and Ldshd), increased 20E titer, and activated the expression of two 20E-response genes (LdEcR and LdFTZ-F1). Thus, LdHR3 functions in regulation of pupation in the Colorado potato beetle.

Arginine-stabilized mPEG-PDLLA (50/50) polymeric micelles of docetaxel by electrostatic mechanism for tumor-targeted delivery.

Arginine-stabilized, docetaxel-loaded polymeric micelles (AR-DTX-PM) were prepared to enhance the physical stability of micelles and control the degradation of docetaxel (DTX). Amphiphilic diblock copolymers, methoxy-(Polyethylene Glycol)-block-Poly (D, L-lactide) (mPEG-PDLLA) were synthesized and used for the formulation of lyophilized DTX-PM powders. The micelles were found to have diameters of 20-30 nm with narrow polydispersity, and the entrapment efficiency was 90-100%. The accumulative release of AR-DTX-PM was higher than that of glucose-dispersed DTX-PM (Glu-DTX-PM). The results of both physical and chemical stability studies showed that the concentration of arginine required for optimum stability was 2.0 mg/ml. Preliminary investigation of the mechanisms of stabilization by arginine suggested that it is due to the electrostatic interaction as well as hydrogen bonds between DTX and arginine. The acute toxicity studies demonstrated that AR-DTX-PM was better tolerated in beagle dogs than DTX injection. However, the pharmacokinetic studies revealed no significant difference in Cmax and AUC of AR-DTX-PM compared to DTX injection. When AR-DTX-PM was administrated at a dose of 30 mg/kg, the antitumor effect was stronger than that of commercial DTX injection at 10 mg/kg, and the increase of administration dose did not cause higher toxicity. The in vivo imaging test showed that the residence time of AR-DTX-PM at tumor sites was longer than its commercial formulation. In a word, it is expected that AR-DTX-PM can reduce systemic toxicity while retaining antitumor efficacy in cancer patients.

Multifunctional targeting daunorubicin plus quinacrine liposomes, modified by wheat germ agglutinin and tamoxifen, for treating brain glioma and glioma stem cells.

Most anticancer drugs are not able to cross the blood-brain barrier (BBB) effectively while surgery and radiation therapy cannot eradicate brain glioma cells and glioma stem cells (GSCs), hence resulting in poor prognosis with high recurrence rates. In the present study, a kind of multifunctional targeting daunorubicin plus quinacrine liposomes was developed for treating brain glioma and GSCs. Evaluations were performed on in-vitro BBB model, murine glioma cells, GSCs, and GSCs bearing mice. Results showed that the multifunctional targeting daunorubicin plus quinacrine liposomes exhibited evident capabilities in crossing the BBB, in killing glioma cells and GSCs and in diminishing brain glioma in mice. Action mechanism studies indicated that the enhanced efficacy of the multifunctional targeting drugs-loaded liposomes could be due to the following aspects: evading the rapid elimination from blood circulation; crossing the BBB effectively; improving drug uptake by glioma cells and GSCs; down-regulating the overexpressed ABC transporters; inducing apoptosis of GSCs via up-regulating apoptotic receptor/ligand (Fas/Fasl), activating apoptotic enzymes (caspases 8, 9 and 3), activating pro-apoptotic proteins (Bax and Bok), activating tumor suppressor protein (P53) and suppressing anti-apoptotic proteins (Bcl-2 and Mcl-1). In conclusion, the multifunctional targeting daunorubicin plus quinacrine liposomes could be used as a potential therapy for treating brain glioma and GSCs.

Liposomes, modified with PTD(HIV-1) peptide, containing epirubicin and celecoxib, to target vasculogenic mimicry channels in invasive breast cancer.

Refractoriness of invasive breast cancer is closely related with the vasculogenic mimicry (VM) channels, which exhibit highly drug resistance to conventional chemotherapies. In the present study, the nanostructured targeting epirubicin plus celecoxib liposomes were developed by modifying a human immunodeficiency virus peptide lipid-derivative conjugate (DSPE-PEG2000-PTDHIV-1) for elimination of invasive breast cancer cells along with their VM channels. The studies were undertaken on invasive human breast cancer MDA-MB-435S cells and MDA-MB-435S xenografts in nude mice. The constructed targeting epirubicin plus celecoxib liposomes were approximately 100 nm in size. In vitro results showed that the targeting liposomes exhibited strong transport ability across cell and nuclei membranes of invasive breast cancer, were able to penetrate and destruct the invasive breast cancer spheroids, initiated apoptosis via activating apoptotic enzymes (caspase 8, 3), and destroyed the VM channels via down-regulating the protein indicators (MMP-9, VE-Cad, FAK, EphA2 and HIF-1α) in invasive breast cancer cells. In vivo results demonstrated that the targeting liposomes displayed a prolonged circulation time in blood system, accumulated more in tumor location, were able to eliminate the VM channels and angiogenesis in tumor tissues, and resulted in a robust overall anticancer efficacy in invasive breast cancer MDA-MB-435S xenografts in nude mice. In conclusion, the nanostructured targeting epirubicin plus celecoxib liposomes could eliminate invasive breast cancer along with the VM channels, hence providing a promising strategy for treatment of invasive breast cancer.