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In an atmosphere of pathogen danger and mistrust during a pandemic, misinformation can induce the urge to penalize the pathogen's origin-destination. This study exams the effect of COVID-19 origin belief (that is, the belief that the virus is human-engineered) on hospitality and tourism outcomes using multi-wave data (U.S. sample: N = 351). The findings suggest that the diverse impact of COVID-19 origin belief (COVID-19 misinformation) on tourists and residents' approach-avoid behaviors can best be modeled in dual explanatory mechanisms. Specifically, COVID-19 origin belief relates to tourism animosity positively but has a negative association with destination image and resident hospitality. The positive indirect effect of COVID-19 origin belief on tourists' willingness to visit is transmitted by tourism animosity. In contrast, the negative indirect effect of COVID-19 origin belief on tourists' willingness to visit and resident hospitality is transmitted by destination image. Tourists and residents' level of education moderates the positive and negative direct and indirect effects. • Belief in COVID-19 misinformation (OB) relates positively to tourism animosity. • But OB relates negatively to destination image and resident hospitality. • Destination image transmits OB's negative effect to willingness to visit and resident hospitality. • Tourism animosity transmits OB's positive effect to willingness to visit. • Level of education serves as a key boundary condition for these effects. [ABSTRACT FROM AUTHOR]

Aim: To estimate potential savings for Australia's health care system through the implementation of an innovative Beacon model of care for patients with complex diabetes.Methods: A prospective controlled trial was conducted comparing a multidisciplinary, community-based, integrated primary-secondary care diabetes service with usual care at a hospital diabetes outpatient clinic. We extracted patient hospitalisation data from the Queensland Hospital Admitted Patient Data Collection and used Australian Refined Diagnosis Related Groups to assign costs to potentially preventable hospitalisations for diabetes.Results: 327 patients with complex diabetes referred by their general practitioner for specialist outpatient care were included in the analysis. The integrated model of care had potential for national cost savings of $132.5 million per year.Conclusions: The differences in hospitalisations attributable to better integrated primary/secondary care can yield large cost savings. Models such as the Beacon are highly relevant to current national health care reform initiatives to improve the continuity and efficiency of care for those with complex chronic disease in primary care. [ABSTRACT FROM AUTHOR]

Abstract: Chitin synthase (CHS) represents an attractive target site for combating insect pests as insect growth and development are strictly dependent on precisely tuned chitin biosynthesis and this pathway is absent in humans and other vertebrates. Current knowledge on CHS in insects, especially their structures, functions, and regulations is still very limited. We report the identification and characterization of two chitin synthase genes, AgCHS1 and AgCHS2, in African malaria mosquito, Anopheles gambiae. AgCHS1 and AgCHS2 were predicted to encode proteins of 1,578 and 1,586 amino acid residues, respectively. Their deduced amino acid sequences show high similarities to other insect chitin synthases. Transcriptional analysis indicated that AgCHS1 was expressed in egg, larval, pupal and adult stages whereas AgCHS2 appeared to be expressed at relatively low levels, particularly during the larval stages as examined by reverse transcription (RT)-PCR and real-time quantitative PCR. Relatively high expression was detected in the carcass followed by the foregut and hindgut for AgCHS1, and the foregut (cardia included) followed by the midgut for AgCHS2. Fluorescence in situ hybridization (FISH) and immunohistochemical analysis revealed new information including the localization of the two enzymes in the ommatidia of the compound eyes, and AgCHS2 in the thoracic and abdominal inter-segmental regions of pupal integument. [Copyright &y& Elsevier]

Abstract: Cytochrome P450 monooxygenases (cytochrome P450s), found in virtually all living organisms, play an important role in the metabolism of xenobiotics such as drugs, pesticides, and plant toxins. We have previously evaluated the responses of the oriental migratory locust (Locusta migratoria) to the pyrethroid insecticide deltamethrin and revealed that increased cytochrome P450 enzyme activity was due to increased transcription of multiple cytochrome P450 genes. In this study, we identified for the first time two new cytochrome P450 genes, which belong to two novel cytochrome P450 gene families. CYP409A1 belongs to CYP409 family whereas CYP408B1 belongs to CYP408 family. Our molecular analysis indicated that CYP409A1 was mainly expressed in fatbodies, midgut, gastric caecum, foregut and Malpighian tubules of the third- and fourth-instar nymphs, whereas CYP408B1 was mainly expressed in foregut, hindgut and muscle of the insects at all developmental stages examined. The expression of these two cytochrome P450 genes were differentially affected by three representative insecticides, including carbaryl (carbamate), malathion (organophosphate) and deltamethrin (pyrethroid). The exposure of the locust to carbaryl, malathion and deltamethrin resulted in reduced, moderately increased and significantly increased transcript levels, respectively, of the two cytochrome P450 genes. Our further analysis of their detoxification roles by using RNA interference followed by deltamethrin bioassay showed increased nymph mortalities by 21.1% and 16.7%, respectively, after CYP409A1 and CYP408B1 were silenced. These results strongly support our notion that these two new cytochrome P450 genes play an important role in deltamethrin detoxification in the locust. [Copyright &y& Elsevier]

Abstract: Insect chitinase 5 (Cht5), a well-characterized enzyme found in the molting fluid and/or integument, is classified as a group I chitinase and is usually encoded by a single gene. In this study, a Cht5 gene cluster consisting of five different chitinase-like genes (AgCht5-1, AgCht5-2, AgCht5-3, AgCht5-4 and AgCht5-5) was identified by a bioinformatics search of the genome of Anopheles gambiae. The gene models were confirmed by cloning and sequencing of the corresponding cDNAs and gene expression profiles during insect development were determined. All of these genes are found in a single cluster on chromosome 2R. Their open reading frames (ORF) range from 1227 to 1713 bp capable of encoding putative proteins ranging in size from 409 to 571 amino acids. The identities of their cDNA sequences range from 52 to 66%, and the identities of their deduced amino acid sequences range from 38 to 53%. There are four introns for AgCht5-1, two for AgCht5-2 and AgCht5-3, only one for AgCht5-4, but none for AgCht5-5 in the genome. All five chitinase-like proteins possess a catalytic domain with all of the conserved sequence motifs, but only AgCht5-1 has a chitin-binding domain. Phylogenetic analysis of these deduced proteins along with those from other insect species suggests that AgCht5-1 is orthologous to the Cht5 proteins identified in other insect species. The differences in expression patterns of these genes at different developmental stages further support that these genes may have distinct functions. Additional searching of the genomes of two other mosquito species led to the discovery of four Cht5-like genes in Aedes aegypti and three in Culex quinquefasciatus. Thus, the presence of a Cht5 gene cluster appears to be unique to mosquito species and these genes may have resulted from gene tandem duplications. [Copyright &y& Elsevier]

Abstract: Chitin synthases are crucial enzymes responsible for chitin biosynthesis in fungi, nematodes and arthropods. We characterized two alternative splicing-derived variants of chitin synthase 1 gene (LmCHS1) from the oriental migratory locust, Locusta migratoria manilensis (Meyen). Each cDNA of the two variants (LmCHS1A and LmCHS1B) consists of 5116 nucleotides that include a 4728-nucleotide open reading frame (ORF) encoding 1576 amino acid residues, and 67- and 321-bp non-coding regions at the 5′- and 3′-ends of the cDNA, respectively. The two variants differ only in one exon consisting of 177 nucleotides that encode 59 amino acid residues. The amino acid sequences within this alternative splicing region are 75% identical between the two variants. Both variants were expressed in all the developmental stages. However, LmCHS1A was predominately expressed in the integument whereas LmCHS1B was mainly expressed in the trachea. Our RNAi-based gene silencing study resulted in a dramatic reduction in the levels of the corresponding mRNA in the locust nymphs injected with dsRNA of LmCHS1, or either of its two variants, LmCHS1A and LmCHS1B. Consequentially, 95, 88 and 51% of mortalities were observed in the locusts injected with the LmCHS1, LmCHS1A and LmCHS1B dsRNA, respectively. The phenotypes resulted from the injection of LmCHS1A dsRNA were similar to those from the injection of LmCHS1 dsRNA, whereas the locusts injected with LmCHS1B dsRNA exhibited crimpled cuticle phenotype. Our results suggest that both variants of chitin synthase 1 are essential for insect growth and development. [ABSTRACT FROM AUTHOR]

Abstract: Chitin synthase (EC 2.4.1.16) is a crucial enzyme responsible for chitin biosynthesis in all chitin-containing organisms. This paper reports a complete cDNA encoding chitin synthase 1 (AqCHS1), change of AqCHS1 mRNA level in response to diflubenzuron exposure, and concentration-dependent effect of diflubenzuron on chitin synthesis in the common malaria mosquito (Anopheles quadrimaculatus). The cDNA consists of 5723 nucleotides, including an open reading frame (ORF) of 4734 nucleotides that encode 1578 amino acid residues and a non-translated region of 989 nucleotides. The deduced amino acid sequence contains all the chitin synthase signature motifs (EDR, QRRRW and SWGTR) and shows 97% identity to that of An. gambiae (AgCHS1, XM_321337). Northern blot and real-time quantitative PCR analyses revealed a significant increase of AqCHS1 mRNA level in the larvae exposed to diflubenzuron at 100 and 500μg/L. As confirmed by real-time quantitative PCR, AqCHS1 mRNA level was enhanced by 2-fold in the larvae exposed to diflubenzuron at 500μg/L for 24h. In contrast, exposures of the larvae to diflubenzuron at 4.0, 20, 100 and 500μg/L for 48h resulted in decreases of chitin content by 9.0%, 43%, 58% and 76%, respectively. Significantly increased AqCHS1 mRNA level associated with decreased chitin synthesis may imply possible inhibition of chitin synthase, or abnormal chitin synthase translocation or chitin microfibril assembly conferred by diflubenzuron. Increased AqCHS1 expression due to increased transcription and/or increased mRNA stability may serve as a feedback mechanism to compensate such an effect in the mosquitoes. Further studies are necessary to elucidate the relationship between reduced chitin synthesis and increased expression of AqCHS1 in order to shed new light on trafficking and regulation of chitin biosynthesis in the mosquito affected by diflubenzuron. [Copyright &y& Elsevier]

• We review molecular basis of chitin biosynthesis of insect peritrophic matrix (PM) • We review the process of chitin modifications and degradation of insect PM. • We identify crucial knowledge gaps in chitin biosynthesis and metabolism of PM. The peritrophic matrix (PM) is an extracellular, semi-permeable biocomposite that lines the midgut of most insects. The PM serves as the first defense in the midgut to resist microorganisms such as viruses, bacteria and other pathogens, and to protect epithelial cells from mechanical damage. The PM also separates the midgut lumen into different compartments, which play important roles in nutrient ingestion and digestion. The PM is a highly dynamic structure that consists mainly of chitin fibers cross-linked by proteins, glycoproteins, and proteoglycans. The PM is continuously biosynthesized, assembled, and degraded in response to feeding and development. Chitin chains are synthesized by several enzymes and organized in several hierarchical levels, in which various PM-associated proteins appear to be essential for maintaining the structural integrity and physiological function of the PM. This review summarizes research advances on molecular components of the PM and their functions, as well as related proteins and enzymes that contribute to PM formation and modification. Crucial gaps in our current understanding of the PM are also addressed. [ABSTRACT FROM AUTHOR]

As an important link in the global network of value chains and supply chains, the evolution of the function of modern ports depends on changes in the distribution of freight volume and shipping routes among ports, along with changes in terms of interdependence and spatial differentiation between various port and shipping service enterprises (PSSEs), such as shipping companies, multimodal transport providers, freight forwarders, and shipping financial institutions. On the basis of defining the connotation of PSSEs, this study takes the Yangtze River Delta as a research case and uses the three-axis rotation method, standard deviational ellipse, and spatial interpolation simulation to analyse the distribution pattern and evolution characteristics of PSSEs from 2002 to 2019. The discrete regression model was used to explore the main factors affecting the location choice of various PSSEs. The characteristics of the spatial and temporal evolution of PSSEs in the Yangtze River Delta are as follows: (1) The structure of the PSSEs in the Yangtze River Delta is in the process of continuous upgrading. It presents a 'medium-high-low' pattern in which medium-end enterprises are dominant, and high-end enterprises are increasing rapidly. (2) The spatial distribution of low- and high-end enterprises is concentrated, and medium-end enterprises are more dispersed. The distribution centre of medium- and low-end enterprises moves westward, while the distribution centre of high-end enterprises turns eastward. (3) The growth rates of medium- and high-end enterprises are much higher than those of low-end enterprises. The analysis of location factors based on the conditional logit model demonstrates that the factors affecting PSSEs are becoming increasingly complex. Besides the influence of traditional location factors such as the economy and transportation of the hinterland, they are also affected by emerging factors such as informatization and the level of financial development. Moreover, the impact of external factors, such as globalization, marketisation, and servitisation, is also rising significantly. [ABSTRACT FROM AUTHOR]

Abstract: Eleven cDNAs encoding glutathione S-transferases (GSTs) were sequenced and characterized in Chironomus tentans, an ecologically important aquatic midge. Phylogenetic analysis revealed seven GSTs in three different cytosolic classes including 4 in sigma (CtGSTs1, CtGSTs2, CtGSTs3, CtGSTs4), 2 in delta (CtGSTd1, CtGSTd2), and 1 in omega (CtGSTo1). The remaining four GSTs (CtGSTu1, CtGSTu2, CtGSTu3, CtGSTu4) were unclassified due to their low relatedness to currently known classes of insect GSTs. Reverse-transcription (RT)-PCR analysis of the 11 GST genes showed that CtGSTd1, CtGSTu2, CtGSTu4, CtGSTs1, CtGSTs2, CtGSTs3, CtGSTs4 and CtGSTo1 were expressed in all tissues examined, including salivary glands, hemolymph, midgut, Malpighian tubules, fatbodies and carcass, whereas CtGSTd2 and CtGSTu1 were expressed in a limited number of tissues. CtGSTs1 and CtGSTs4 appeared to be the only two genes, of which expressions can be detected in eggs, whereas all the 11 GST genes showed various expression patterns in the four larval instars. However, expressions of CtGSTd2, CtGSTu1 and CtGSTu2 were not detectable in pupal and adult stages. Real-time quantitative PCR confirmed that the herbicide alachlor increased CtGSTd1, CtGSTs2 and CtGSTs3 gene expression by 2.1-, 2.8- and 4.3-fold, respectively, when fourth-instar midges were exposed to alachlor at 1000 μg/L for 72 h. Such increased gene expressions were associated with 2.2- and 1.8-fold decreases of total GST activities in vivo when CDNB and DCNB were used as substrates, respectively. Further studies showed that 65.5 and 73.5% of GST activities were inhibited in vitro by alachlor at 100 and 1000 μg/L, respectively. Because alachlor has been known as an electrophilic substrate that can be conjugated by glutathione (GSH), rapid in vitro inhibition of GST activities by alachlor suggested that decreased GST activities were likely caused by the depletion of GSH. However, alachlor may regulate different GST genes, as found in other organisms, leading to significantly increased transcriptional levels of CtGSTd1, CtGSTs2 and CtGSTs3 in out of 11 GST genes examined in this study. [Copyright &y& Elsevier]

In this study, we obtained four alternative splicing transcripts of intracellular copper/zinc superoxide dismutase 1 (icCuZnSOD1) in Oxya chinensis. OcicCuZnSOD1a has all common characteristics of CuZnSOD family and is a canonical CuZnSOD. OcicCuZnSOD1b is missing a Zn binding site. OcicCuZnSOD1c lacks Zn ion and is a Cu-only SOD. OcicCuZnSOD1d is missing a CuZnSOD conserved sequence and lacks the E-loop, a conserved disulfide bond, and an active site arginine. OcicCuZnSOD1a was the most heat-resistant and OcicCuZnSOD1c was the most unstable at high temperatures above 55 °C. They were stable at a wide pH range, especially in alkaline conditions. The four variants expressed at the throughout developmental stages and had various tissue expression patterns. OcicCuZnSOD1a and OcicCuZnSOD1d were significantly induced by 8.79 mM CuCl 2 and OcicCuZnSOD1b was significantly up-regulated by 14.67 mM CuCl 2. OcicCuZnSOD1a was significantly inhibited by 19.13 mM ZnSO 4 while OcicCuZnSOD1d were significantly induced by 22.61 mM ZnSO 4. Disc diffusion assay showed that the four isoforms of OcicCuZnSOD1 made the killing zones smaller surrounding the CdCl 2 -soaked filter discs. However, the reduction ratios of OcicCuZnSOD1a were the highest. These results implied that the four transcripts played roles in defense against CdCl 2 -induced oxidative stress while OcicCuZnSOD1a had stronger antioxidant capacity. • Four alternative splicing transcripts of icCuZnSOD1 were obtained in Oxya chinensis. • OcicCuZnSOD1c is missing Zn ion and is a Cu-only SOD. • The responses of the four transcripts to CuCl 2 and ZnSO 4 stresses were various. • The four isoforms were stable at 25–55 °C and at alkaline conditions. • The four isoforms took a part in removing ROS induced by CdCl 2 stress. [ABSTRACT FROM AUTHOR]

The Drosophila hindgut is a classical model to study organogenesis. The adult hindgut originates from the precursor cells in the larval hindgut. However, the territory of these cells has still not been well determined. A ring of wingless (wg)-expressing cells lies at the anterior zone of both the larval and adult hindgut. The larval Wg ring was thought as a portion of precursor of the adult hindgut. By applying a cell lineage tracing tool (G-TRACE), we demonstrate that larval wg -expressing cells have no cell lineage contribution to the adult hindgut. Additionally, adult Wg ring cells do not divide and move posteriorly to replenish the hindgut tissue. Instead, we determine that the precursors of the adult pylorus and ileum are situated in the cubitus interruptus (ci)-expressing cells in the anterior zone, and deduce that the precursor stem cells of the adult rectum locate in the trunk region of the larval pylorus including hedgehog (hh)-expressing cells. Together, this research advances our understanding of cell lineage origins and the development of the Drosophila hindgut. [Display omitted] • Adult Wg ring cells do not divide and move posteriorly to replenish the hindgut tissue. • Larval Wg ring in the anterior zone of hindgut was not the precursors of adult hindgut. • The progenitors of the adult pylorus and ileum were situated in the ci expressing cells in the larval anterior zone. • The progenitors of the adult rectum were located in the trunk region of pylorus including hh expressing cells. [ABSTRACT FROM AUTHOR]

• We identified a BTB domain-containing protein 6 gene, LmBTBD6 , from Locusta migratoria transcriptome database. • LmBTBD6 was highly expressed in the wing pads and regulated by the LmEcR-LmHR39-mediated 20E signaling pathway. • Depletion of LmBTBD6 transcripts caused wing defects in the transition from nymph to adult. • LmBTBD6 regulated the expression of wing development-related genes and wing-specific cuticle protein genes. The development of insect wings is a complex process controlled by a series of genes, whereas the mechanism of wing development of orthoptera insects is less frequently reported. In the present study, a BTB domain-containing protein 6 (LmBTBD6) gene was identified from Locusta migratoria. Its encoded protein belongs to the BTB-BACK-PHR subfamily, and is highly conserved among insect species. LmBTBD6 was mainly expressed in the wing pads and showed high expression on day 7 of fifth-instar nymphs. LmBTBD6 responded to induction by 20-Hydroxyecdysone (20E) in vivo , and its expression was significantly suppressed after knocking down the ecdysone receptor gene LmEcR and nuclear receptor gene LmHR39. Deficiency of LmBTBD6 did not show visible phenotype in the wing pads transition from nymph to nymph of L. migratoria , but caused wing defects in the transition from nymph to adult. After silencing of LmBTBD6 , the transcription of wing development-related genes (LmSal411 , LmSal468 , and LmHth) and the wing-specific cuticle protein genes (LmACP7 and LmACP8) of L. migratoria were significantly suppressed. Thus, LmBTBD6 that regulated by the LmEcR-LmHR39-mediated 20E signaling pathway is involved in wing development during the nymph to adult transition by regulating the expression of wing development-related genes and wing-specific cuticle protein genes. [ABSTRACT FROM AUTHOR]

Cytochrome P450 monooxygenases (P450s) constitute a large superfamily of heme-thiolate proteins that are involved in the biosynthesis or degradation of endogenous compounds and detoxification of exogenous chemicals. It has been reported that P450s could serve as odorant-degrading enzymes (ODEs) to inactivate odorants to avoid saturating the antennae. However, there is little information about P450s in the antennae of Locusta migratoria. In the current work, we conducted an antenna transcriptome analysis and identified 92 P450s, including 68 full-length and 24 partial sequences. Phylogenetic analysis showed that 68 full-length P450s were grouped into four clans: CYP2, CYP3, CYP4, and mitochondria clans. Tissue, stage, and sex-dependent expressions of these 68 P450s were investigated. The results showed that 4 P450s were antenna-specific, whereas others were antenna-rich but also expressed in other tissues, implying their various potential roles in the antennae. In addition, the responses of seven selected P450s to five gramineous plant volatiles and four locust volatiles were determined. CYP6MU1 could be induced by almost all compounds tested, suggesting its important roles in odorant processing. Different P450s exhibited diverse responses to odorants, indicating that specific regulation of P450 expression by odorants might modulate the sensitivity of the olfactory responses to various chemicals. • The antenna transcriptome of Locusta migratoria was successfully constructed. • Ninety two P450s were identified, including 68 full-length and 24 partial sequences. • Four P450s were antenna-specific and 8 P450s were antenna-rich. • The responses of seven P450s to nine plant and locust volatiles were investigated. • CYP6MU1 was significantly up-regulated by almost all chemicals tested. [ABSTRACT FROM AUTHOR]

The chitin modifying deacetylases (CDA) CDA1 and CDA2 have been reported to play partially redundant roles during insect cuticle formation and molting and tracheal morphogenesis in various insect species. In order to distinguish possible functional differences between these two enzymes, we analyzed their function during wing development in the fruit fly Drosophila melanogaster. In tissue-specific RNA interference experiments, we demonstrate that DmCDA1 (Serpentine, Serp) and DmCDA2 (Vermiform, Verm) have distinct functions during Drosophila adult wing cuticle differentiation. Chitosan staining revealed that Serp is the major enzyme responsible for chitin deacetylation during wing cuticle formation, while Verm does not seem to be needed for this process. Indeed, it is questionable whether Verm is a chitin deacetylase at all. Atomic force microscopy suggested that Serp and Verm have distinct roles in establishing the shape of nanoscale bumps at the wing surface. Moreover, our data indicate that Verm but not Serp is required for the laminar arrangement of chitin. Both enzymes participate in the establishment of the cuticular inward barrier against penetration of xenobiotics. Taken together, correct differentiation of the wing cuticle involves both Serp and Verm in parallel in largely non-overlapping functions. Image 1 • The chitin deacetylases Serp and Verm are needed for wing cuticle formation in Drosophila. • Serp but not Verm is able to convert chitin to chitosan. • Lamellar organisation of the procuticle requires Verm but not Serp activity. • Wing cuticle impermeability depends on both Serp and Verm. • Serp and Verm have opposing effects on wing surface topography. [ABSTRACT FROM AUTHOR]

Abstract Insect cytochrome P450 monooxygenase (CYP) plays a key role in the detoxification of insecticides. In this study, four cDNA sequences of CYP6 genes were identified and characterized. Transcription levels of LmCYP6HC1 and LmCYP6HCL1 were high in first- and fourth-instar nymph stages, respectively. LmCYP6HN1 was primarily expressed in the egg to third-instar nymph stages, while LmCYP6HQ1 was predominantly expressed in the stages from fourth-instar nymph to the adult. The four CYP6 genes were predominantly distributed in the antenna, brain, fat body, integument, and hemolymph. Piperonyl butoxide exposure inhibited total CYP activity and synergized the toxicity of carbamates and pyrethroids. Knockdown of LmCYP6HL1 , LmCYP6HN1 , and LmCYP6HQ1 increased nymph mortality following exposure to carbaryl, and silencing of LmCYP6HC1 , LmCYP6HL1 , LmCYP6HN1 , and LmCYP6HQ1 comprehensively raised nymph mortality following exposure to fluvalinate. Knockdown of LmCYP6HL1 or LmCYP6HN1 significantly increased nymph mortality following exposure to cypermethrin or fenvalerate, respectively. These results suggest that the CYP6 family plays a key role in determining the susceptibility of Locusta migratoria to both carbamates and pyrethroids. Highlights • The cDNA sequences of four CYP6 family genes from Locusta migratoria were analyzed and characterized. •Piperonyl butoxide synergizes the toxicity of carbamates and pyrethroids. •The CYP6 family plays a key role in determining susceptibility to both carbamates and pyrethroids in Locusta migratoria. [ABSTRACT FROM AUTHOR]

Abstract Insect cuticle is a composite made of chitin filaments embedded in a proteinaceous matrix, consisting mainly of structural cuticular proteins. In the present study, an endocuticle structural glycoprotein gene, LmAbd-9 , was characterized based on the Locusta migratoria transcriptome. LmAbd-9 encodes a glycoprotein with a chitin binding domain 4, belonging to RR-1 subclass of the CPR family, which has two potential O-linked glycosylation sites (S115 and T137) at which glycosylation modification may occur. LmAbd-9 was highly expressed in the integument and showed periodic expression during molting. The expression levels of LmAbd-9 were significantly down-regulated after injection with 20-hydroxyecdysone (20E) for 6, 12, and 24 h, whereas it was upregulated after double-stranded RNA-mediated RNA interference of the 20E receptor gene LmEcR and LmFTZ-F1beta at day 2 of fifth instar nymphs for 48 h. After injection of ds LmAbd-9 on day 2 of fifth instar nymphs, the insects could normally molt to adults and showed no macroscopic phenotype; however, the cuticle of the adults was thinner, and there were significantly fewer endocuticular lamellae than in the control. Thus, LmAbd-9 that negatively regulated by the 20E signaling pathway was involved in the formation of the endocuticle in L. migratoria. Highlights • We characterized an endocuticle structural glycoprotein gene, LmAbd-9 , from Locusta migratoria transcriptome database. • LmAbd-9 was highly expressed in the integument and showed periodic expression during molting. • The expression of LmAbd-9 can be repressed by 20E signaling pathway. • LmAbd-9 was involved in the formation of the endocuticle during locust molting. [ABSTRACT FROM AUTHOR]

• 3D computational fluid dynamics (CFD) model was used to MBRs structural design. • Mixed liquor suspended solids (MLSS) concentration increases shear stress uniformity. • Optimization of bubble diameter to 5 mm improves shear stress distribution. • Side baffle length extension improves shear stress uniformity on membrane surface. • Novel in-situ aeration method enhances membrane antifouling potential. The optimization of membrane bioreactors (MBRs) involves a critical challenge in structural design for mitigation of membrane fouling. To address this issue, a three-dimensional computational fluid dynamics (CFD) model was utilized in this study to simulate the hydrodynamic characteristics of a flat sheet (FS) MBR. The optimization of the membrane module configuration and operating conditions was performed by investigating key parameters that altered the shear stress and liquid velocity. The mixed liquor suspended solids (MLSS) concentration was found to increase the shear stress, leading to a more uniform distribution of shear stress. By optimizing the appropriate bubble diameter to 5 mm, the shear stress on the membrane surface was optimized with relatively uniform distribution. Additionally, extending the side baffle length dramatically improved the uniformity of the shear stress distribution on each membrane. A novel in-situ aeration method was also discovered to promote turbulent kinetic energy by 200 times compared with traditional aeration modes, leading to a more uniform bubble streamline. As a result, the novel in-situ aeration method demonstrated superior membrane antifouling potential in the MBR. This work provides a new approach for the structural design and optimization of MBRs. The innovative combination of the CFD model, optimization techniques, and novel in-situ aeration method has provided a substantial contribution to the advancement of membrane separation technology in wastewater treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

Cytochrome P450 monooxygenases (P450s) are important enzymes for biotransformations of various endogenous and xenobiotic substances in various organisms. In this study, we examined microsomal P450 protein content and enzymatic activity in four major detoxification tissues dissected from fifth-instar nymphs of the migratory locust ( Locusta migratoria ). The highest microsomal P450 protein content was found in the gastric caeca (a part of the midgut), followed by the midgut, Malpighian tubules and fat bodies. Microsomal P450s showed the highest aromatic hydroxylation, O -dealkylation and O -dearylation activities towards six of the seven model substrates examined in the fat bodies. Although the gastric caeca showed the highest P450 protein content, the enzymatic activities towards six of the seven model substrates were the lowest in this tissue. Further, the midgut, gastric caeca and fat bodies showed significant metabolic activities towards two pyrethroid insecticides (deltamethrin and fluvalinate), but no significant activities towards the other four insecticides (malathion, chlorpyrifos, carbaryl and methoprene). These results support our conclusions: 1) total P450 protein content alone cannot be reliably used to predict its enzymatic activity, and 2) insect P450 enzymatic activity is both tissue and substrate dependent. [ABSTRACT FROM AUTHOR]

Abstract Chitinases, key enzymes involved in degradation of chitin, have been repeatedly shown to play an indispensable role during insect post-embryonic molting processes at stage transitions. However, how chitinases affect insect embryonic development remains to be analyzed. In this study, we investigated the role of chitinase 5–1 (LmCht5-1) during embryonic development of the hemimetabolous insect Locusta migratoria. LmCht5-1 transcript levels were high in pro-nymphs during late embryogenesis. The respective protein localized to both the pro-nymphal and, to a much lesser extent, the newly formed nymphal cuticle. After injection of double stranded RNA against LmCht5-1 into 8 days old embryos, LmCht5-1 transcripts were strongly reduced. Most of ds LmCht5-1- injected pro-nymphs failed to develop to first-instar nymphs and died at or before hatching. Histological analyzes showed that degradation of the pro-nymph cuticle was blocked in these animals. At the ultra-structural level, we found that LmCht5-1 was needed for the degradation of the lamellar procuticle, while the separation of the procuticle from the epicuticle and epidermis (apolysis) was independent of LmCht 5 -1 function. Taken together, our results indicate that LmCht5-1 and other yet unknown degrading enzymes act in parallel at distinct positions of the cuticle during molting of the pro-nymph to the first-instar nymph during locust embryogenesis. Graphical abstract Image 1 Highlights • LmCht5-1 was highly transcripted in pro-nymphs and localized to both the pro-nymphal and the newly formed nymphal cuticle. • ds LmCht5-1 injected pro-nymphs failed to develop to first-instar nymphs and died at or before hatching. • LmCht5-1 was needed for the degradation of the procuticle but not involved in separation of the procuticle from the epicuticle and epidermis. [ABSTRACT FROM AUTHOR]

Abstract Cytochrome P450 monooxygenases (CYPs) belong to a large superfamily of heme-containing enzymes catalyzing at least 60 different types of chemically distinct reactions. Insect CYPs play key roles in biotransformation of insecticides and plant chemicals, and are implicated in insecticide resistance and insect adaptation to their host plants. Insect CYPs are well studied in model insects, but little is known about the CYP superfamily in paurometabolous insects. We employed Illumina sequencing technology to identify 71 partial and 78 full-length open reading frames (ORFs) of LmCYP genes from the migratory locust (Locusta migratoria), one of the most destructive paurometabolous insect pests in the world. Seventy-eight LmCYPs with complete ORFs were formally named and classified into 19 families and 43 subfamilies. The majority of LmCYPs were mainly expressed in nymphal and adult stages, but LmCYP expression varied widely among thirteen different tissues examined. Regulatory elements were predicted in the promoter regions of LmCYP genes, and subsequent exposure of locusts to 12 different exogenous chemicals showed that 2-tridecanone and xanthotoxin were the most effective at increasing LmCYP expression. Our results represent the first transcriptome-wide analysis of the LmCYP superfamily from migratory locust, and provide a foundation for understanding the physiological functions, functional diversity, evolution, and regulatory mechanisms controlling the expression of the CYP gene superfamily in the locust. Graphical abstract Image 1 Highlights • We revealed 71 partial and 78 full-length open reading frames of CYP genes from L. migratoria by Illumina sequencing. • The 78 CYP s with complete open reading frames were named and classified into 19 families and 43 subfamilies. • LmCYP gene expression patterns varied significantly among 13 tissues and seven developmental stages. • Xanthotoxin and 2-tridecanone were the most effective among 12 different exogenous chemicals at increasing LmCYP expression. • These results can help better understand functional diversity and regulatory mechanisms of CYP genes in insects. [ABSTRACT FROM AUTHOR]

During growth and development of insects, the steroid hormone 20-Hydroxyecdysone (20E) regulates the molting process through activation of a series of genes including E74 , E75 and HR3 by the 20E receptor EcR. Here, we analyzed the function of LmHR3 in the migratory locust Locusta migratoria . By sequence comparison, we first identified and characterized the putative nuclear receptor protein (LmHR3) based on L. migratoria transcriptome data. The full length cDNA is 2272 bp long encoding a protein of 455 amino acids that contains a DNA binding domain (zinc finger) and a ligand binding domain. Phylogenetic analyses showed that LmHR3 has a high homology with the ortholog from Blattaria . RT-qPCR results revealed that LmHR3 has a low level expression in the early days of 5th instar nymphs, and then increases and peaks at day 6, followed by a decrease to low levels before ecdysis. The LmHR3 , hence, coincides with the profile of circulating 20E levels. Indeed, we show that transcription of LmHR3 is induced by 20E in vivo , and significantly suppressed by successfully knocking down expression of LmEcR . After injection of dsRNA for LmHR3 (ds LmHR3 ) at day 2 of earlier instar nymphs (3rd and 4th instar) and final instar nymphs (5th instar), none of the nymphs were able to molt normally, and eventually died. Chitin staining and ultra-structural analysis showed that both the synthesis of the new cuticle and the degradation of the old cuticle were blocked in the ds LmHR3 treated nymphs. Especially, chitin synthesis genes ( LmUAP1 and LmCHS1 ) and chitinase genes ( LmCHT5 and LmCHT10 ) were significantly down-regulated in the ds LmHR3 treatment group. Together, our results suggest that LmHR3 is involved in the control of chitin synthesis and degradation during L. migratoria molting. [ABSTRACT FROM AUTHOR]

Background NADPH-cytochrome P450 reductase (CPR) plays important roles in cytochrome P450-mediated metabolism of endogenous and exogenous compounds, and participates in cytochrome P450-related detoxification of insecticides. However, the CPR from Locusta migratoria has not been well characterized and its function is still undescribed. Results The full-length of CPR gene from Locusta migratoria ( LmCPR ) was cloned by RT-PCR based on transcriptome information. The membrane anchor region, and 3 conserved domains (FMN binding domain, connecting domain, FAD/NADPH binding domain) were analyzed by bioinformatics analysis. Phylogenetic analysis showed that LmCPR was grouped in the Orthoptera branch and was more closely related to the CPRs from hemimetabolous insects. The LmCPR gene was ubiquitously expressed at all developmental stages and was the most abundant in the fourth-instar nymphs and the lowest in the egg stage. Tissue-specific expression analysis showed that LmCPR was higher expressed in ovary, hindgut, and integument. The CPR activity was relatively higher in Malpighian tubules and integument. Silencing of LmCPR obviously reduced the enzymatic activity of LmCPR, and enhanced the susceptibility of Locusta migratoria to carbaryl. Conclusion These results suggest that LmCPR contributes to the susceptibility of L. migratoria to carbaryl and could be considered as a novel target for pest control. [ABSTRACT FROM AUTHOR]

The insect cuticle is an extracellular matrix that consists of the polysaccharide chitin, proteins, lipids and organic molecules that are arranged in distinct horizontal layers. In Drosophila melanogaster , these layers are not formed sequentially, but, at least partially, at the same time. Timing of the underlying molecular mechanisms is conceivably crucial for cuticle formation. To study this issue, we determined the time period during which the function of Knickkopf (Knk), a key factor of chitin organization, is required for wing cuticle differentiation in D. melanogaster . Although knk is expressed throughout metamorphosis, we demonstrate that its expression 30 h prior and 48 h after pupariation is essential for correct wing cuticle formation. In other words, expression beyond this period is futile. Importantly, manipulation of Knk expression during this time causes wing bending suggesting an effect of Knk amounts on the physical properties of the wing cuticle. Manipulation of Knk expression also interferes with the structure and function of the cuticle surface. First, we show that the shape of surface nano-structures depends on the expression levels of knk . Second, we find that cuticle impermeability is compromised in wings with reduced knk expression. In summary, despite the extended supply of Knk during metamorphosis, controlled amounts of Knk are important for correct wing cuticle differentiation and function in a concise period of time. [ABSTRACT FROM AUTHOR]

Superoxide dismutase (SOD) is the first line of defense against oxidative damage. Malathion is an organophosphate insecticide and can induce the production of reactive oxygen species (ROS) and cause the intracellular oxidative stress. The present study was undertaken to examine the effects of malathion on SODs activity and their transcriptional levels in Oxya chinensis (Thunberg) (Orthoptera: Acrididae). The results showed that total SOD and MnSOD activities increased as a dose-dependent manner while CuZnSOD activity has no significant changes after malathion treatments. Total SOD and MnSOD activities were the highest at the concentration of 0.8 μg μL −1 malathion treatment and increased significantly about 1.81- and 2.48-fold compared with the control, respectively. Increased mRNA expression of MnSOD , ecCuZnSOD1 , and ecCuZnSOD2 were observed after malathion treatments. Moreover, the alteration of MnSOD transcript was similar to the profiles of MnSOD activity. These results suggested that the up-regulation expression of MnSOD transcript led to the increase of MnSOD activity in order to eliminate the excessive ROS caused by malathion. In addition, we evaluated the role of individual SOD gene in malathion stress by using RNAi and recombinant SOD proteins. The results showed that ROS contents increased significantly after the silencing of MnSOD and ecCuZnSOD1 genes. The OD values of the E. coli cells transformed with pET-28a-OcMnSOD plasmid were 1.13–1.31-fold and 1.08–1.33-fold higher than those of cells with pET-28a plasmids under 0.4 and 0.8 μg μL −1 malathion treatments, respectively. These findings indicated that MnSOD exerted an important role in defense oxidative stress caused by malathion. [ABSTRACT FROM AUTHOR]

ATP-binding cassette (ABC) transporters constitute a large superfamily of proteins that mediate transport of a diverse number of substrates including nutrients, lipids and xenobiotics across membranes serving a variety of developmental and physiological functions. Here, we report on the molecular properties and biological roles of the ABC transporter LmABCH-9C in the migratory locust Locusta migratoria . LmABCH-9C was expressed continuously during nymphal development in all tissues including the integument. Expression was highest just after molting. Suppression of LmABCH-9C transcript levels by RNA interference (RNAi) in nymphs provoked death during or soon after molting to the next stage. These nymphs lost weight within minutes after molting. Moreover, high humidity rescued the lethality of molted ds LmABCH-9C -injected nymphs. In histological experiments, we find that the amounts of inner-cuticular lipids are reduced in nymphs with suppressed LmABCH-9C expression. These data together indicate that LmABCH-9C is needed for lipid-dependent desiccation resistance, paralleling the function of ABCH-9C in Tribolium castaneum . Hence, the function of this ABC transporter seems to be conserved across insect species ranging from hemimetabolous ( L. migratoria ) to holometabolous ( T. castaneum ) species. In addition, we find that cuticle inward impermeability is compromised in nymphs with reduced LmABCH-9C function. In summary, consistent with the model that cuticular lipids are necessary to prevent desiccation and penetration of xenobiotics in insects, we hypothesize that LmABCH-9C is involved in the construction of a lipid-based barrier at the surface of the cuticle especially after molting to protect the animal against uncontrolled water loss and entry. Susceptibility of this ABC transporter to RNAi-mediated knockdown designates it as an excellent target for RNAi-based insect pest control. [ABSTRACT FROM AUTHOR]

20-hydroxyecdysone (20E) has been implicated in regulating the immune response in insects. Conflicting conclusions on 20E regulating immunity have been reported in model holometabolous species. However, in hemimetabolous insects, the role of 20E as an immune-suppressor or activator and the mechanism remains unclear. The migratory locust Locusta migratoria is a representative member of hemimetabolous insects. Here, digital gene expression (DGE) profiles of Locusta migratoria treated with 20E were analyzed. Pattern recognition receptors [peptidoglycan recognition protein ( PGRP-SA) , PGRP-LE , and gram-negative binding protein ( GNBP3 )] and antimicrobial peptides ( defensin , diptericin , and i-type lysozyme ) were significantly induced by 20E in fat body. These immune-related genes significantly increased their mRNA levels during the high-20E stage. Antibacterial activities in plasma were enhanced after 20E injection and during the high-20E developmental stage. Conversely, when 20E signal was suppressed by RNAi of EcR (ecdysone receptor), the expression levels of these genes and antibacterial activities failed to be increased by 20E injection and during the high-20E developmental stage, and the mortality increased after being infected by entomogenous fungus. The knockdown of PGRP-SA inhibited the expression level of defensin , diptericin and i-type lysozyme in fat body and reduced antibacterial activities in plasma. 20E injection could not significantly induce the expression of antimicrobial peptides after RNAi of PGRP-SA . These results demonstrated that 20E enhanced the immune response by activating PGRP-SA in L. migratoria . [ABSTRACT FROM AUTHOR]

Application of RNA interference (RNAi) for insect pest management is limited by variable efficiency of RNAi in different insect species. In Locusta migratoria , RNAi is highly efficient through injection of dsRNA, but oral delivery of dsRNA is much less effective. Efforts to understand this phenomenon have shown that dsRNA is more rapidly degraded in midgut fluid than in hemolymph due to nuclease enzyme activity. In the present study, we identified and characterized two full-length cDNAs of double-stranded RNA degrading enzymes (dsRNase) from midgut of L. migratoria , which were named LmdsRNase2 and LmdsRNase3 . Gene expression analysis revealed that LmdsRNase2 and LmdsRNase3 were predominantly expressed in the midgut, relatively lower expression in gastric caeca, and trace expression in other tested tissues. Incubation of dsRNA in midgut fluid from LmdsRNase3- suppressed larvae or control larvae injected with ds GFP resulted in high levels of degradation; however, dsRNA incubated in midgut fluid from LmdsRNase2- suppressed larvae was more stable, indicating LmdsRNase2 is responsible for dsRNA degradation in the midgut. To verify the biological function of LmdsRNase2 in vivo , nymphs were injected with ds GFP , ds LmdsRNase2 or ds LmdsRNase3 and chitinase 10 ( LmCht10 ) or chitin synthase 1 ( LmCHS1 ) dsRNA were orally delivered. Mortality associated with reporter gene knockdown was observed only in locusts injected with ds LmdsRNase2 (48% and 22%, for ds LmCht10 and ds LmCHS1 , respectively), implicating LmdsRNase2 in reducing RNAi efficiency. Furthermore, recombinantly expressed LmdsRNase2 fusion proteins degraded dsRNA rapidly, whereas LmdsRNase3 did not. These results suggest that rapid degradation of dsRNA by dsRNase2 in the midgut is an important factor causing low RNAi efficiency when dsRNA is orally delivered in the locust. [ABSTRACT FROM AUTHOR]

Lipophorin is the most abundant lipoprotein particle in insect hemolymph. Lipophorin receptor (LPR) is a glycoprotein that binds to the lipophorin and mediates cellular uptake and metabolism of lipids by endocytosis. However, the roles of LPR in uptake of lipids in the integument and ovary remain unknown in the migratory locust (Locusta migratoria). In present study, we characterized the molecular properties and biological roles of LmLPR in L. migratoria. The LmLPR transcript level was high in the first 2 days of the adults after eclosion, then gradually declined. LmLPR was predominately expressed in fat body, ovary and integument. Using immuno-detection methods, we revealed that LmLPR was mainly localized in the membrane of oenocytes, epidermal cells, fat body cells and follicular cells. RNAi-mediated silencing of LmLPR led to a slight decrease of the cuticle hydrocarbon contents but with little effect on the cuticular permeability. However, the neutral lipid content was significantly decreased in the ovary after RNAi against LmLPR , which led to a retarded ovarian development. Taken together, our results indicated that LmLPR is involved in the uptake and accumulation of lipids in the ovary and plays a crucial role in ovarian development in L. migratoria. Therefore, LmLPR could be a promising RNAi target for insect pest management by disrupting insect ovarian development. • LmLPR silencing provoked a dramatic decrease in the content of lipids in ovary, consequently retarded the development of ovary. [ABSTRACT FROM AUTHOR]

Dicers belong to a class of large RNase III multidomain ribonucleases and are central components of the RNA interference (RNAi) pathways. In insects, Dicer-2 has been known to cleave long double-stranded RNA (dsRNA) in small interfering RNA (siRNA)-mediated-RNAi pathway. However, Dicer-1 is responsible for cleaving precursor microRNAs (pre28 miRNAs) in miRNA-mediated RNAi pathway. In this study, we identified one LmDicer-1 and two LmDicer-2 (LmDicer-2a and LmDicer-2b) genes in Locusta migratoria. The RNAi of RNAi assay showed that knockdown of each of the Dicer genes reduced RNAi efficiency against a target gene (Lmβ-Tubulin), suggesting that all these genes participated in the siRNA-mediated RNAi pathway. Sequence analyses of the siRNAs generated from ds Lmβ-Tubulin after silencing each LmDicer gene showed no significant difference in the pattern of siRNAs mapped to ds Lmβ-Tubulin. This result indicated that all the three LmDicers are capable of generating siRNAs from the dsRNA. We then generated recombinant proteins consisting of different domains using Escherichia coli expression system and incubated each recombinant protein with ds Lmβ-Tubulin. We found that the recombinant Dicer proteins successfully cleaved ds Lmβ-Tubulin. However, LmDicer-2a-R lacking dsRBD domain lost activity, suggesting that dsRBD domain is critical for Dicer function. Furthermore, overexpression of these proteins in Drosophila S2 cells improved RNAi efficiency. Our siRNA affinity chromatography and LC-MS/MS analysis identified LmDicer-2a, LmDicer-2b, LmR2D2, LmAgo2a, LmAgo1, LmStaufen and LmTARBP2 as constituents of RNA-induced silencing complex. Taken together, these data show that both LmDicer-1 and two LmDicer-2s all participate in siRNA-mediated RNAi pathway and likely contribute to high RNAi efficiency in L. migratoria. [Display omitted] • Biological roles of three Dicer genes in RNAi were characterized in the locust. • All Dicers are capable of generating functional siRNA from dsRNA in vivo for RNAi. • LmDicer-2a lacks dsRNA-binding domain but retains dsRNA cleavage activity in vivo. • A dsRNA-binding protein may help LmDicer-2a bind to dsRNA for dicing activity. • All three Dicers contribute to high RNAi efficiency of siRNA-mediated RNAi pathway. [ABSTRACT FROM AUTHOR]

Objective Drunk driving (blood alcohol concentration (BAC) 80 mg/100 ml) was upgraded to become a criminal offence under China's Criminal Law in May 2011. While this had a major road safety benefit, there was still a high level of alcohol related crashes and fatalities. This paper develops recommendations based on a programme of research undertaken in 2012 that examined the perceptions of general motor vehicle drivers, convicted drunk driving offenders and traffic police about drinking and driving and law enforcement in the cities of Guangzhou and Yinchuan. Alcohol misuse problems were also explored using the Alcohol Use Disorders Identification Test (AUDIT). This paper integrates the findings to examine existing problems in alcohol management, law enforcement, education and rehabilitation and provides recommendations for addressing alcohol-related driving in China. Methods A multi-study cross-sectional research programme was conducted in two Chinese cities involving general drivers, drunk driving offenders and traffic police. In total, 16 traffic police officers were interviewed and 105 traffic police officers were surveyed. In addition, 207 drunk driving offenders in detention facilities and 802 general motor vehicle drivers were surveyed. Results Traffic police resources including human resources and facilities such as breathalysers were reported as insufficient in both cities. There were problems reported in the process of law enforcement, and shortcomings in police knowledge of factors involved in drink/drunk driving and in the practice of conducting breath alcohol testing (BAT). Knowledge about legal BAC levels and how to keep under the legal limit was very low among general motor vehicle drivers and drunk driving offenders. Proportions with alcohol misuse problems in the two driver groups were high, especially among offenders. Conclusions Recommendations to manage alcohol-related driving are proposed for the three groups of traffic police, general motor vehicle drivers and drunk driving offenders. In particular, traffic police resources need to be improved and further education provided to police on the general deterrence potential of BAT. There should be enhanced community education and publicity to improve knowledge of drink driving regulations and how to avoid breaking the law. Alcohol misuse problems should be addressed, particularly for drunk driving offenders. [ABSTRACT FROM AUTHOR]

Objective This study was conducted after a legislative amendment criminalising drunk driving (BAC > 80 mg/100 ml) had been in force for a year and investigated whether drunk driving offenders in Yinchuan, China were aware of the law, and whether their knowledge of and exposure to enforcement and the existence of alcohol use disorders were related to their alcohol-involved driving behaviour. The results were compared with results from an earlier study in Guangzhou, China. Method A survey was conducted from July to October 2012 in Yinchuan to collect information on drunk driving offenders’ knowledge and practice in relation to alcohol-involved driving. The Alcohol Use Disorders Identification Test (AUDIT) was used to assess hazardous drinking levels. In total, 106 drunk driving offenders were recruited while in detention. The findings were compared with those of the Guangzhou study, where the same procedure was used to recruit 101 drunk driving offenders. Results The mean age of the sample was 31.7 years (SD = 8.1; range 17–59 years). Males constituted 96% of the sample. The mean age at which offenders reported starting to drink alcohol was 18.7 years (SD = 3.2; range 10–26 years). Driver’s licenses had been held for an average of 8.5 years. The status of knowledge in relation to alcohol-involved driving in Yinchuan was slightly lower in proportion than in Guangzhou. The rate of alcohol-involved driving reported in the previous 12 months in Yinchuan (43%) was slightly higher than in Guangzhou (39%). The proportion of recidivists in Guangzhou (21.8%) was higher than Yinchuan’s (10.4%). On average, offenders had experienced 1.6 police alcohol breath tests in the previous year (SD = 1.3; range 1–10). AUDIT scores indicated that a substantial proportion of the offenders had high levels of alcohol use disorders. Discussion Limited awareness of legal alcohol limits might contribute to drunk driving offences. The high level of alcohol consumption by many offenders suggests that hazardous drinking levels may be a contributor. Recidivist drivers also had higher AUDIT scores, which suggest there may be benefit in using the AUDIT to identify potential drink drivers and recidivists, subject to further research. [ABSTRACT FROM AUTHOR]

In this study, mechanisms of membrane fouling caused by polysaccharides with different molecular structures in polyaluminum chloride (PACl) coagulation-ultrafiltration (C-UF) process were explored. Carrageenan and xanthan gum were chosen for model foulants of straight chain and branched chain polysaccharides, respectively. Filtration experiments showed that, with PACl dosage of 0–5 mM, specific filtration resistance (SFR) of carrageenan and xanthan solution showed a unimodal pattern and a continuous decrease pattern, respectively. A series of experimental characterizations indicated that the different SFR pattern was closely related to structure of foulants layer. Density functional theory (DFT) calculation suggested that Al3+ preferentially coordinating with the terminal sulfonyl groups of carrageenan chains to promote gel layer formation at low PACl concentration (0.15 mM). There existed a chemical potential gap between bound water in gel layer and free water in the permeate, so that, filtration through gel layer corresponded to rather high SFR for overcoming this gap. In contrast, Al3+ coordinating with the non-terminal sulfonyl groups of carrageenan at high PACl concentration caused transition from gel layer to cake layer, leading to SFR decrease. However, xanthan gum itself can form a dense gel layer with a complex polymer network by virtue of the interlacing of main chains and branches. Al3+ coordinating with the carboxyl groups on branched chains of xanthan gum resulted in clusters of polymer chains and flocculation, corresponding to the reduced SFR. This proposed molecular-level mechanism well explained membrane fouling behaviors of polysaccharides with different molecular structure, and also facilitated to optimize C-UF process for water treatment. [Display omitted] • Specific filtration resistance (SFR) of straight chain carrageenan showed a unimodal pattern with PACl addition. • SFR of branched chain xanthan gum showed a continuous decrease pattern with PACl addition. • The different SFR pattern was closely related to structure of foulants layer. • Coordination order, gel morphology change and chemical potential explained the SFR patterns. • This work proposed a molecular-level mechanism for PACl coagulation-ultrafiltration process. [ABSTRACT FROM AUTHOR]

This study evaluated the transcriptional responses of two metallothionein (MT) genes ( OcMT1 and OcMT2 ) in various tissues (brain, optic lobe, Malpighian tubules, fat bodies, foregut, gastric caeca, midgut and hindgut) of Oxya chinensis (Thunberg) (Orthoptera: Acridoidea) after exposed to the trace metals cadmium (Cd), copper (Cu) and zinc (Zn) for 48 h. The study revealed that the exposure of O. chinensis to each of the three metals at the median lethal concentration (LC 50 ) or lower concentration(s) up-regulated the transcriptions of both OcMT1 and OCMT2 in the eight tissues except for OcMT1 and OcMT2 with Cd in brain and gastric caeca, respectively, and OcMT2 with Cu in gastric caeca. These results suggested that the exposure of O. chinensis to the metals may enhance MT biosynthesis that protects tissues by binding these metals in various tissues. To examine possible histopathological effect of the metals, we examined the histological changes in the fat bodies after O. chinensis was exposed to each of these metals at LC 50 . The exposure of Cd significantly reduced the size and number of adipocytes as compared with the control. However, such an effect was not observed in O. chinensis exposed to either Cu or Zn. These results suggested that fat bodies might be either significantly affected by Cd or play a crucial role in detoxification of excessive trace metals. [ABSTRACT FROM AUTHOR]

Carboxylesterases (CarEs) play a crucial role in detoxification of xenobiotics and resistance to insecticides in insects. In this study, two cDNAs of CarE genes ( LmCesA4 and LmCesA5 ) were sequenced from the migratory locust, Locusta migratoria . The cDNAs of LmCesA4 and LmCesA5 putatively encoded 538 and 470 amino acid residues, respectively. The deduced amino acid sequences of the two CarE genes showed 45.0% identities, possessed highly conserved catalytic triads (Ser-Glu-His), and clustered in phylogenetic analysis. These results suggest that they are homologous genes. Both CarE genes were expressed throughout the developmental stages. However, LmCesA4 was predominately expressed in the midgut (including the gastric caeca) and fat bodies, whereas LmCesA5 was mainly expressed in the gastric caeca. The in situ hybridization results showed that the transcripts of the two genes were localized in apical and basal regions of the columnar cells in the gastric caeca. Gene silencing followed by insecticide bioassay increased the mortalities of deltamethrin-, malathion-, and carbaryl-treated locusts by 29.5%, 31.0% and 20.4%, respectively, after the locusts were injected with LmCesA4 double-stranded RNA (dsRNA). In contrast, the injection of LmCesA5 dsRNA did not significantly increase the susceptibility of the locusts to any of these insecticides. These results suggest that these genes not only show different tissue expression patterns but also play different roles in insecticide detoxification. [ABSTRACT FROM AUTHOR]

The duplication of chitinase 5 ( Cht5 ) into two to five different genes has been reported only in mosquito species to date. Here, we report the duplication of Cht5 genes ( LmCht5-1 and LmCht5-2 ) in the migratory locust ( Locusta migratoria ). Both LmCht5-1 (505 aa) and LmCht5-2 (492 aa) possess a signal peptide and a catalytic domain with four conserved motifs, but only LmCht5-1 contains a chitin-binding domain. Structural and phylogenetic analyses suggest that LmCht5-1 is orthologous to other insect Cht5 genes, whereas LmCht5-2 might be newly duplicated. Both LmCht5 genes were expressed in all tested tissues with LmCht5-1 highly expressed in hindgut and LmCht5-2 highly expressed in integument, foregut, hindgut and fat bodies. From the fourth-instar nymphs to the adults, LmCht5-1 and LmCht5-2 showed similar developmental expression patterns with transcript peaks prior to each nymphal molting, suggesting that their expression levels are similarly regulated. Treatment with 20-hydroxyecdysone (20E; the most active molting hormone) and reducing expression of EcR (ecdysone receptor gene) by RNAi increased and decreased expression of both LmCht5 genes, respectively, indicating that both genes are responsive to 20E. Although transcript level of LmCht5-2 is generally 10-fold higher than that of LmCht5-1 , RNAi-mediated suppression of LmCht5-1 transcript led to severe molting defects and lethality, but such effects were not seen with RNAi of LmCht5-2 , suggesting that the newly duplicated LmCht5-2 is not essential for development and survivorship of the locust. [ABSTRACT FROM AUTHOR]

Patients with ischemic heart disease receiving reperfusion therapy still need to face left ventricular remodeling and heart failure after myocardial infarction. Reperfusion itself paradoxically leads to further cardiomyocyte death and systolic dysfunction. Ischemia/reperfusion (I/R) injury can eliminate the benefits of reperfusion therapy in patients and causes secondary myocardial injury. Mitochondrial dysfunction and structural disorder are the basic driving force of I/R injury. We summarized the basic relationship and potential mechanisms of mitochondrial injury in the development of I/R injury. Subsequently, this review summarized the natural products (NPs) that have been proven to targeting mitochondrial therapeutic effects during I/R injury in recent years and related cellular signal transduction pathways. We found that these NPs mainly protected the structural integrity of mitochondria and improve dysfunction, such as reducing mitochondrial division and fusion abnormalities, improving mitochondrial Ca2+ overload and inhibiting reactive oxygen species overproduction, thereby playing a role in protecting cardiomyocytes during I/R injury. This data would deepen the understanding of I/R-induced mitochondrial pathological process and suggested that NPs are expected to be transformed into potential therapies targeting mitochondria. [Display omitted] • Mitochondrial reactive oxygen species have emerged as an important mechanism of myocardial ischemia/reperfusion injury. • In ischemia/reperfusion-induced cardiac injury, natural products can target mitochondria to exert cardioprotection. • Natural products are potential therapies to protect mitochondria against ischemia/reperfusion injury. [ABSTRACT FROM AUTHOR]

Nuclear receptors (NRs) function as key factors in diverse signaling and metabolic pathways. Previous studies have focused on the roles of a nuclear receptor, hormone receptor 4 (HR4), mainly in holometabolous insects, while current knowledge of its function in hemimetabolous insects is still limited. In this study, we identified a HR4 gene in the orthopteran species Locusta migratoria. The full-length open reading frame of LmHR4 comprises 2694-nucleotides encoding a polypeptide of 897 amino acids, which contained a DNA-binding and a ligand-binding domain. Analyzing LmHR4 expression by quantitative reverse-transcription PCR (RT-qPCR) revealed that LmHR4 was highly expressed in integument, hindgut and fat body. During development from 3rd and 5th nymphal instars, the expression of LmHR4 reached maximal levels before ecdysis. We further demonstrated that LmHR4 expression is induced by 20-hydroxyecdysone (20E) and suppressed by silencing LmEcR, suggesting that LmHR4 expression is controlled by 20E signaling. The ds LmHR4 -injected nymphs failed to molt and remained in the nymphal stage until death. Hematoxylin and eosin staining of the integument indicated that apolysis in the ds LmHR4 -injected insects was delayed compared to that in control insects. Chitin staining and ultra-structural analysis showed that both the synthesis of the new cuticle and the degradation of the old cuticle were blocked in ds LmHR4 -injected insects. Silencing LmHR4 decreased 20E titer and down-regulated the transcript levels of genes involved in chitin synthesis and degradation. Taken together, these results suggest that LmHR4 is essential for the formation of epidermal cuticle by mediating the 20E signaling to regulate the expression of chitin synthesis and degradation genes. [Display omitted] •The expression of LmHR4 is induced by 20E through LmEcR. •Nymphs injected with ds LmHR4 failed to molt. •LmHR4 silencing blocks the synthesis of new cuticle and degradation of old cuticle. •Knockdown of LmHR4 results in decreased 20E titer. • LmHR4 regulates genes involved in chitin synthesis and degradation. [ABSTRACT FROM AUTHOR]