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Low-density lipoprotein receptor-related protein 2 (LRP2) is a multifunctional endocytic receptor expressed in epithelial cells. In mammals, it acts as an endocytic receptor that mediates the cellular uptake of cholesterol-containing apolipoproteins to maintain lipid homeostasis. However, little is known about the role of LRP2 in lipid homeostasis in insects. In the present study, we investigated the function of LRP2 in the migratory locust Locusta migratoria (LmLRP2). The mRNA of LmLRP2 is widely distributed in various tissues, including integument, wing pads, foregut, midgut, hindgut, Malpighian tubules and fat body, and the amounts of LmLRP2 transcripts decreased gradually in the early stages and then increased in the late stages before ecdysis during the nymphal developmental stage. Fluorescence immunohistochemistry revealed that the LmLRP2 protein is mainly located in cellular membranes of the midgut and hindgut. Using RNAi to silence LmLRP2 caused molting defects in nymphs (more than 60%), and the neutral lipid was found to accumulate in the midgut and surface of the integument, but not in the fat body, of dsLmLRP2-treated nymphs. The results of a lipidomics analysis showed that the main components of lipids (diglyceride and triglyceride) were significantly increased in the midgut, but decreased in the fat body and hemolymph. Furthermore, the content of total triglyceride was significantly increased in the midgut, but markedly decreased in the fat body and hemolymph in dsLmLRP2-injected nymphs. Our results indicate that LmLRP2 is located in the cellular membranes of midgut cells, and is required for lipid export from the midgut to the hemolymph and fat body in locusts.

Wings are an important flight organ of insects. Wing development is a complex process controlled by a series of genes. The flightless wing pad transforms into a mature wing with the function of migratory flight during the nymph-to-adult metamorphosis. However, the mechanism of wing morphogenesis in locusts is still unclear. This study analyzed the microstructures of the locust wing pads at pre-eclosion and the wings after eclosion and performed the comparative transcriptome analysis. RNA-seq identified 25,334 unigenes and 3,430 differentially expressed genes (DEGs) (1,907 up-regulated and 1,523 down-regulated). The DEGs mainly included cuticle development (LmACPs), chitin metabolism (LmIdgf4), lipid metabolism-related genes, cell adhesion (Integrin), zinc finger transcription factors (LmSalm, LmZF593 and LmZF521), and others. Functional analysis based on RNA interference and hematoxylin and eosin (H&E) staining showed that the three genes encoded zinc finger transcription factors are essential for forming wing cuticle and maintaining morphology in Locusta migratoria. Finally, the study found that the LmSalm regulates the expression of LmACPs in the wing pads at pre-eclosion, and LmZF593 and LmZF521 regulate the expression of LmIntegrin/LmIdgf4/LmHMT420 in the wings after eclosion. This study revealed that the molecular regulatory axis controls wing morphology in nymphal and adult stages of locusts, offering a theoretical basis for the study of wing development mechanisms in hemimetabolous insects.

Abstract This study examined the relationship between family capital (FC) and academic achievement in geography along with the mediating role of creativity. The main objective was to determine if FC is a positive predictor of creativity and geographic achievement, and whether creativity completely or partially mediates the relationship between FC and geographic achievement. 1268 high school students participated in this study using the Family Capital Questionnaire (FCQ), the Innovative Behavior Scale (IBS), and students’ class geography scores. SPSS 26 and Amos software were used to analyze the descriptive statistics and the correlation between the main variables. The mediating role of creativity was tested using PROCESS version 4. The correlation analyses showed that FC positively affected academic achievement in geography (β = 0.382, SE = 0.019). Creativity also demonstrated a positive effect on geography academic achievement (β = 0.376, SE = 0.022). The mediation analysis showed that creativity mediated and buffered the relationship between FC and academic achievement in geography. Thus, FC directly affected students’ academic achievement in geography and indirectly affected their creativity. This clearly demonstrates that student characteristics and the external environment should be emphasized in geography education, while placing a strong focus on cultivating individual creativity.

Abstract Background Although previous studies have found a close relationship between sense of place and creativity, few studies have been conducted considering the micro-environment of the classroom. The mediating role of classmate relationships in the association between students’ sense of place and creativity remains unclear. Methods This study explores classmate relationships as a mediating factor in the relationship between sense of place and creativity. Therefore, we considered a sample of 1555 Chinese high-school students and used a paper-based questionnaire survey. Data analysis was performed using SPSS 24.0, PROCESS 3.2 plugin, and AMOS. Results Sense of place in the micro-environment of the classroom has a significant positive predictive effect on creativity. Sense of place also has a significant positive predictive effect on peer relationships. The mediation analysis reveals that peer relationships play a mediating role in the relationship between the sense of place and creativity. Conclusions This study revealed the associations between sense of place, classmate relationships, and creativity. Creativity is better expressed in students with a strong sense of place in the classroom. Moreover, a student’s sense of place can enhance their creativity by influencing their peer relationships. These findings enrich the research in educational psychology within the classroom, providing new insights for fostering creativity.

RNA interference (RNAi) is a specific post-transcriptional gene-silencing phenomenon, which plays an important role in the regulation of gene expression and the protection from transposable elements in eukaryotic organisms. In Drosophila melanogaster, RNAi can be induced by microRNA (miRNA), endogenous small interfering RNA (siRNA), or exogenous siRNA. However, the biogenesis of miRNA and siRNA in these RNAi pathways is aided by the double-stranded RNA binding proteins (dsRBPs) Loquacious (Loqs)-PB, Loqs-PD or R2D2. In this study, we identified three alternative splicing variants of Loqs, namely Loqs-PA, -PB, and -PC in the orthopteran Locusta migratoria. We performed in vitro and in vivo experiments to study the roles of the three Loqs variants in the miRNA- and siRNA-mediated RNAi pathways. Our results show that Loqs-PB assists the binding of pre-miRNA to Dicer−1 to lead to the cleavage of pre-miRNA to yield matured miRNA in the miRNA-mediated RNAi pathway. In contrast, different Loqs proteins participate in different siRNA-mediated RNAi pathways. In exogenous siRNA-mediated RNAi pathway, binding of Loqs-PA or LmLoqs-PB to exogenous dsRNA facilitates the cleavage of dsRNA by Dicer−2, whereas in endogenous siRNA-mediated RNAi pathway, binding of Loqs-PB or Loqs-PC to endogenous dsRNA facilitates the cleavage of dsRNA by Dicer−2. Our findings provide new insights into the functional importance of different Loqs proteins derived from alternative splicing variants of Loqs in achieving high RNAi efficiency in different RNAi pathways in insects.

In the intricate landscape of the global food system, a nuanced understanding of dynamic evolution patterns and driving mechanisms of food trade network is essential for advancing insights into the African food trade and maintaining the food security of Africa. This paper constructs a framework for analyzing the food trade network from a comparative perspective by comparing and analyzing the evolution of food trade networks in China, the United States, Russia, the European Union, and African countries. The development trend of food trade between China, Russia, the United States, the European Union, and African countries is relatively good. China, the United States, Russia, and the European Union export far more food to African countries than they import, and bilateral food trade plays an important role in alleviating food supply shortages in Africa. The food trade networks between China, the United States, Russia, the European Union, and African countries exhibit a butterfly-shaped structure centered in Africa, and the overall intensity of bilateral trade linkages is gradually increasing. France has the greatest control over the food trade network between China, the United States, Russia, the European Union, and African countries, and the influence of the United States on the food trade network between China, the United States, Russia, the European Union, and African countries is increasing. China’s independence in the food trade network between China, the United States, Russia, the European Union, and African countries is enhanced, but its control ability is limited. The impact of differences in total population, differences in food production, and geographical borders on the trade network between China, the United States, the European Union, and African countries tends to decrease, while the influence of differences in the proportion of agricultural employment, differences in the arable land available for food production, and institutional distance tends to increase.

Potassium sorbate (PS) is a preservative widely used in the food, pharmaceutical, and cosmetics industries. Improper and careless use of PS can lead to various health issues and potential environmental problems. Drosophila is capable of making rapid and sensitive responses to stress or other stimuli. Here we utilized Drosophila as a model organism to evaluate the potential toxicity of PS. Our study revealed that PS ingestion reduced the lifespan and fecundity of Drosophila. In addition, excessive PS ingestion led to cell apoptosis and ROS accumulation in the midgut. Furthermore, PS intake also enhanced the mitophagy of midgut cells. Strikingly, PS affected the cell differentiation progression as well, leading to the production of more enteroendocrine (EE) cells. We further demonstrated that the expression of notch (N), a vital player in intestinal stem cell (ISC) differentiation, was down-regulated in the midgut. This indicates that the differentiation progression was affected potentially by repressing the N expression.

Glypicans are closely associated with organ development and tumorigenesis in animals. Dally-like (Dlp), a membrane-bound glypican, plays pivotal roles in various biological processes in Drosophila. In this study, we observed that an excess of Dlp led to the malformation of legs, particularly affecting the distal part. Accordingly, the leg disc was shrunken and frequently exhibited aberrant morphology. In addition, elevated Dlp levels induced ectopic cell death with no apparent cell proliferation changes. Furthermore, Dlp overexpression in the posterior compartment significantly altered Wingless (Wg) distribution. We observed a marked expansion of Wg distribution within the posterior compartment, accompanied by a corresponding decrease in the anterior compartment. It appears that excess Dlp guides Wg to diffuse to cells with higher Dlp levels. In addition, the distal-less (dll) gene, which is crucial for leg patterning, was up-regulated significantly. Notably, dachshund (dac) and homothorax (hth) expression, also essential for leg patterning and development, only appeared to be negligibly affected. Based on these findings, we speculate that excess Dlp may contribute to malformations of the distal leg region of Drosophila, possibly through its influence on Wg distribution, dll expression and induced cell death. Our research advances the understanding of Dlp function in Drosophila leg development.

Fushi-tarazu factor 1 (FTZ-F1) is a class of transcription factors belonging to the nuclear receptor superfamily and an important molting regulator in insects; however, its detailed function in the molting process of Locusta migratoria is still unclear. This study identified two FTZ-F1 transcripts (LmFTZ-F1-X1 and LmFTZ-F1-X2) in L. migratoria. The classical domains of FTZ-F1 were present in their protein sequences and distinguished based on their variable N-terminal domains. Reverse-transcription quantitative polymerase chain reaction analysis revealed that LmFTZ-F1-X1 and LmFTZ-F1-X2 were highly expressed in the integument. RNA interference (RNAi) was used to explore the function of LmFTZ-F1s in the molting of the third-instar nymph. Separate LmFTZ-F1-X1 or LmFTZ-F1-X2 silencing did not affect the normal development of third-instar nymphs; however, the simultaneous RNAi of LmFTZ-F1-X1 and LmFTZ-F1-X2 caused the nymphs to be trapped in the third instar stage and finally die. Furthermore, the hematoxylin-eosin and chitin staining of the cuticle showed that the new cuticles were thickened after silencing the LmFTZ-F1s compared to the controls. RNA-seq analysis showed that genes encoding four cuticle proteins, two chitin synthesis enzymes, and cytochrome P450 303a1 were differentially expressed between dsGFP- and dsLmFTZ-F1s-injected groups. Taken together, LmFTZ-F1-X1 and LmFTZ-F1-X2 are involved in the ecdysis of locusts, possibly by regulating the expression of genes involved in cuticle formation, chitin synthesis, and other key molting processes.

Rationale & Objective: Little is known about hospital admissions in nondialysis patients with chronic kidney disease (CKD) before death or starting kidney replacement therapy (KRT). Study Design: Retrospective observational cohort study Setting & Participants: Hospitalizations among 7,201 patients with CKD from 10 public renal clinics in Queensland (QLD), enrolled in the CKD.QLD registry starting in May 2011, were followed for 25,496.34 person-years until they started receiving KRT or died, or until June 30, 2018. Predictors: Demographic and clinical characteristics of patients with CKD. Outcomes: Hospital admissions. Analytical Approach: We evaluated the association of demographic and clinical features with hospitalizations, length of hospital stay, and cost. Results: Approximately 81.5% of the patients were admitted at least once, with 42,283 admissions, costing Australian dollars (AUD) 231 million. The average number of admissions per person-year was 1.7, and the cost was AUD 9,060, 10 times and 2 times their Australian averages, respectively. Single (1-day) admissions constituted 59.2% of all the hospital episodes, led by neoplasms (largely chemotherapy), anemia, CKD-related conditions and eye conditions (largely cataract extractions), but only 14.8% of the total costs. Approximately 41% of admissions were >1-day admissions, constituting 85.2% of the total costs, with cardiovascular conditions, respiratory conditions, CKD-related conditions, and injuries, fractures, or poisoning being the dominant causes. Readmission within 30 days of discharge constituted >42% of the admissions and 46.8% costs. Admissions not directly related to CKD constituted 90% of the admissions and costs. More than 40% of the admissions and costs were through the emergency department. Approximately 19% of the hospitalized patients and 27% of the admissions did not have kidney disease mentioned as either principal or associate causes. Limitations: Variable follow-up times because of different dates of consent. Conclusions: The hospital burden of patients with CKD is mainly driven by complex multiday admissions and readmissions involving comorbid conditions, which may not be directly related to their CKD. Strategies to prevent these complex admissions and readmissions should minimize hospital costs and outcomes. Plain-Language Summary: We analyzed primary causes, types, and costs of hospitalizations among 7,201 patients with chronic kidney disease (CKD) from renal speciality clinics across Queensland, Australia, over an average follow-up of 3.54 years. The average annual cost per person was $9,060, and was the highest in those with more advanced CKD, higher age, and with diabetes. More than 85% of costs were driven by more complex hospitalizations with longer length of stay. Cardiovascular disease was the single largest contributor for hospitalizations, length of hospital stay, and total costs. Readmission within 30 days of discharge, particularly for the same disorder, and multiday admissions should be the main targets for mitigation of hospital costs in this population.

PurposeFamily environment has the major impact on children’s academic development. The aim of this study was to research the relationship between family capital and academic achievement in geography. Further, geospatial thinking, as a form of spatial thinking focusing on the scale of the geographical environment, is closely related to family environment and academic achievement in geography. Thus, the study was more specifically to apply a mediation model to explore the potential mediating role of geospatial thinking.MethodsA total of 1,037 upper-secondary-school students in Western China were surveyed using t the Family Capital Questionnaire and the Geospatial Thinking Test Questionnaire. SPSS (version 26.0) was used for descriptive statistical analysis and correlation analysis. The PROCESS plug-in (version 4.0) was used to test the mediating effect of geospatial thinking.Results(1) The correlation analysis showed that family capital has a positive effect on academic achievement in geography and is related to geospatial thinking. Moreover, geospatial thinking exerts a positive effect on academic achievement in geography. (2) The results of mediation analysis indicated that geospatial thinking plays mediating and buffering roles in the relationship between family capital and academic achievement in geography after controlling for family residence and gender. The direct and indirect effects accounted for 75.32% and 24.68% of the total effect, respectively.ConclusionThe results indicated that family capital not only affected academic achievement in geography directly but also indirectly through geospatial thinking. This finding provides some ideas for the development of geography education, which suggests that geography educators need to pay more attention to the influence of the family environment on students’ geography learning in curriculum design and teaching processes. Also, the mediating role of geospatial thinking further uncovers the mechanisms underlying the academic achievement in geography. Therefore, it is necessary to focus on both students’ family capital and geospatial thinking in the process of geography learning, and carry out more geospatial thinking training to improve academic achievement in geography.

Aim. Anaemia among patients with chronic kidney disease (CKD) leads to poor overall outcomes. This study explores anaemia and its impact on nondialysis CKD (NDD-CKD) patients. Methods. 2,303 adults with CKD from two CKD.QLD Registry sites were characterised at consent and followed until start of kidney replacement therapy (KRT), death, or censor date. Mean follow-up was 3.9 (SD 2.1) years. Analysis explored the impact of anaemia on death, KRT start, cardiovascular events (CVE), admissions, and costs in these NDD-CKD patients. Results. At consent, 45.6% patients were anaemic. Males were more often anaemic (53.6%) than females, and anaemia was significantly more common over the age of 65 years. The prevalence of anaemia was highest among CKD patients with diabetic nephropathy (27.4%) and renovascular disease (29.2%) and lowest in patients with genetic renal disease (3.3%). Patients with admissions for gastrointestinal bleeding had more severe anaemia, but accounted for only the minority of cases overall. Administration of ESAs, iron infusions, and blood transfusions were all correlated with more severe degrees of anaemia. The number of hospital admissions, length of stay, and hospital costs were all strikingly higher with more severe degrees of anaemia. Adjusted hazard ratios (CI 95%) of patients with moderate and severe anaemia vs. no anaemia for subsequent CVE, KRT, and death without KRT were 1.7 (1.4–2.0), 2.0 (1.4–2.9), and 1.8 (1.5–2.3), respectively. Conclusion. Anaemia is associated with higher rates of CVE, progression to KRT and death in NDD- CKD patients, and with greater hospital utilisation and costs. Preventing and treating anaemia should improve clinical and economic outcomes.

BackgroundThe COVID-19 pandemic has led to public health problems, including depression. There has been a significant increase in research on depression during the COVID-19 pandemic. However, little attention has been paid to the overall trend in this field based on bibliometric analyses.MethodsCo-Occurrence (COOC) and VOSviewer bibliometric methods were utilized to analyze depression in COVID-19 literature in the core collection of the Web of Science (WOS). The overall characteristics of depression during COVID-19 were summarized by analyzing the number of published studies, keywords, institutions, and countries.ResultsA total of 9,694 English original research articles and reviews on depression during COVID-19 were included in this study. The United States, China, and the United Kingdom were the countries with the largest number of publications and had close cooperation with each other. Research institutions in each country were dominated by universities, with the University of Toronto being the most productive institution in the world. The most frequently published author was Ligang Zhang. Visualization analysis showed that influencing factors, adverse effects, and coping strategies were hotspots for research.ConclusionThe results shed light on the burgeoning research on depression during COVID-19, particularly the relationship between depression and public health. In addition, future research on depression during COVID-19 should focus more on special groups and those at potential risk of depression in the general population, use more quantitative and qualitative studies combined with more attention to scale updates, and conduct longitudinal follow-ups of the outcomes of interventions. In conclusion, this study contributes to a more comprehensive view of the development of depression during COVID-19 and suggests a theoretical basis for future research on public health.

Few studies have examined how family capital affects the sense of place, and the effect of spatial thinking on the relationship between the two is unclear. This study constructs a mediation model to examine the impact of family capital on sense of place and the mediation effect of geospatial thinking. A total of 1,004 upper-secondary-school students were surveyed using the Family Capital Questionnaire, the Geospatial Thinking Test, and the Sense of Place Scale. The correlation analysis showed that family capital has a positive effect on both sense of place and geospatial thinking. Moreover, there is also a significant positive correlation between geospatial thinking and sense of place. The results of mediation analysis indicated that geospatial thinking plays mediating and buffering roles in the relationship between family capital and sense of place after controlling for gender and residential address. The direct and indirect effects accounted for 73.31 and 26.69% of the total effect, respectively. Specifically, family capital is a significant positive predictor of both sense of place and geospatial thinking, and geospatial thinking partially mediates the relationship between family capital and sense of place. Students from better family backgrounds are more likely to have a better geospatial thinking and sense of place, as well as geospatial thinking promotes the development of a sense of place. Therefore, both family capital and geospatial thinking should be considered when we want to examine and develop individuals’ level of sense of place.

PurposeThis study explored the relationship between sense of place and academic achievement in geography and used a mediation model to verify the mediating role of creativity in this relationship.MethodsA total of 1,037 upper secondary school students were surveyed using the Sense of Place Scale, the Innovative Behavior Scale, and their geography test scores. SPSS (version 26.0) was used for descriptive statistical analysis and correlation analysis. The PROCESS plug-in (version 4.0) was used to test the mediating effect of creativity.Results(1) The correlation analysis showed that sense of place has a positive effect on academic achievement in geography and is related to creativity. Moreover, creativity exerts a positive effect on academic achievement in geography (2). The results of mediation analysis indicated that creativity plays mediating and buffering roles in the relationship between sense of place and academic achievement in geography after controlling for gender and residential address. The direct and indirect effects accounted for 65.708 and 34.292% of the total effect, respectively.ConclusionsThe results indicated that sense of place affected not only academic achievement in geography directly but also creativity indirectly. This conclusion provides certain ideas for the development of geography curriculums. Since academic achievement in geography is related to both sense of place and creativity, it is necessary to pay more attention to integrating sense of place in geography education and to foster creativity in curriculum development and teaching of geography.

Anthracyclines (ANTs) are a class of anticancer drugs widely used in oncology. However, the clinical application of ANTs is limited by their cardiotoxicity. The mechanisms underlying ANTs-induced cardiotoxicity (AIC) are complicated and involve oxidative stress, inflammation, topoisomerase 2β inhibition, pyroptosis, immunometabolism, autophagy, apoptosis, ferroptosis, etc. Ferroptosis is a new form of regulated cell death (RCD) proposed in 2012, characterized by iron-dependent accumulation of reactive oxygen species (ROS) and lipid peroxidation. An increasing number of studies have found that ferroptosis plays a vital role in the development of AIC. Therefore, we aimed to elaborate on ferroptosis in AIC, especially by doxorubicin (DOX). We first summarize the mechanisms of ferroptosis in terms of oxidation and anti-oxidation systems. Then, we discuss the mechanisms related to ferroptosis caused by DOX, particularly from the perspective of iron metabolism of cardiomyocytes. We also present our research on the prevention and treatment of AIC based on ferroptosis. Finally, we enumerate our views on the development of drugs targeting ferroptosis in this emerging field.

Group I chitin deacetylases (CDAs), CDA1 and CDA2, play an essential role in cuticle formation and molting in the process of insect wing development. A recent report showed that trachea are able to take up a secreted CDA1 (serpentine, serp) produced in the fat body to support normal tracheal development in the fruit fly Drosophila melanogaster. However, whether CDAs in wing tissue were produced locally or derived from the fat body remains an open question. To address this question, we applied tissue-specific RNAi against DmCDA1 (serpentine, serp) and DmCDA2 (vermiform, verm) in the fat body or the wing and analyzed the resulting phenotypes. We found that repression of serp and verm in the fat body had no effect on wing morphogenesis. RT-qPCR showed that RNAi against serp or verm in the fat body autonomously reduced their expression levels of serp or verm in the fat body but had no non-autonomous effect on the expression in wings. Furthermore, we showed that inhibition of serp or verm in the developing wing caused wing morphology and permeability deficiency. Taken together, the production of Serp and Verm in the wing was autonomous and independent of the fat body.

The success of the degradation of the extraembryonic serosal cuticle and the second embryonic cuticle (pro-nymphal cuticle) is essential for the development and molting of nymph from egg in Orthoptera Locusta migratoria. Chitinase 5 is an important gene for chitin degradation in nymphs and in the egg stage. In this study, we investigated the important roles of chitinase 5-1 (LmCht5-1) and chitinase 5-2 (LmCht5-2) in the degradation of the serosal and pro-nymphal cuticles during locust embryonic development. The serosal cuticle degrades from 7-day-old embryos (E7) to E13, along with the degradation of the pro-nymphal cuticle, which begins at E12 to E14. The mRNA and protein of LmCht5-1 and LmCht5-2 are expressed during the degradation process of the serosal cuticle and the pro-nymphal cuticle. RNAi experiments at the embryonic stage show that both dsLmCht5-1 and dsLmCht5-2 contribute to the failure of development in early and late embryogenesis. Further, during the serosal cuticle molting process, ultra-structure analysis indicated that dsLmCht5-1 prevented the loss of the coarse chitin layer in the upper part in both early and late embryogenesis. Meanwhile, dsLmCht5-2 blocked the degradation of the lower fine chitin layer at the early stage and blocked the chitin degradation of loose coarse chitin in the late molting process. During the degradation of the pro-nymphal cuticle, dsLmCht5-1 suppresses chitin degradation between layers in the procuticle, while dsLmCht5-2 suppresses chitin degradation into filaments inside of the layer. In summary, our results suggest that both LmCht5-1 and LmCht5-2 contribute to the degradation of the serosal and pro-nymphal cuticles during the locust embryonic stage.

Chronic kidney disease (CKD) is one of the most common chronic diseases in the western world. In Australia, around 1.7 million Australians aged 18 years and over (about one in ten) have indicators of CKD, and 1.8 million hospitalisations were associated with CKD in 2017–18. There is currently very little understanding of the impact of CKD on health service utilisation and costs. Understanding the disease pathways of CKD and its effects on service utilisation and patient outcomes is essential to predicting the course of the disease in the future, its effects on health services utilisation and capacity to better manage the burden of premature deaths or the need for dialysis that results from CKD. We describe the establishment of a data linkage framework to study hospital admissions of CKD patients in the public renal services in the Australian state of Queensland, and its potential to advance understanding of their course and outcomes. Seven years of retrospective data (2011–2018) on hospital-based health services utilisation were provided by Queensland Health for all 7,341 patients who enrolled in the CKD.QLD Registry up to Jan 2019. The data were supplied from three datasets: the Queensland Hospital Admitted Patient Data Collection, the Queensland Registrar General deaths, and the Activity Based Funding Model Output data. In addition, data were supplied from two cohorts of de-identified patients admitted to hospital in the same interval (22,023 patients each), who were not in the CKD.QLD Registry, the first with CKD and the second without CKD as indicated by International Classification of Diseases and Related Health Problems, Tenth Revision, Australian Modification. The comprehensive and multifaceted data via the data linkage will enable us to identify opportunities for efficiencies in management of patients with CKD and for interventions that improve their outcomes.

Objective To explore factors behind inpatient admissions by high-cost users (HCUs) in pre-end-stage chronic kidney disease (CKD).Design Retrospective analysis of CKD.QLD Registry and hospital admissions of the Queensland Government Department of Health recorded between 1 July 2011 and 30 June 2016.Setting Queensland public and private hospitals.Participants 5096 individuals with CKD who consented to the CKD.QLD Registry via 1 of 11 participating sites.Main outcomes Associations of HCU status with patient characteristics, pathways and diagnoses behind hospital admissions at 12 months.Results Age, advanced CKD, primary renal diagnosis, cardiovascular disease and hypertension were predictors of the high-cost outcome. HCUs were more likely than non-HCUs to be admitted by means of episode change (relative risk: 5.21; 95% CI 5.02 to 5.39), 30-day readmission (2.19; 2.13 to 2.25), scheduled readmission (1.29; 1.11 to 1.46) and emergency (1.07; 1.02 to 1.13), for diagnoses of the nervous (1.94; 1.74 to 2.15), circulatory (1.24; 1.14 to 1.34) and respiratory (1.2; 1.03 to 1.37) systems and other factors influencing health status (1.92; 1.74 to 2.09).Conclusions The high relevance of episode change and other factors influencing health status revealed that a substantial part of excess demand for inpatient care was associated with discordant conditions often linked to frailty, decline in psychological health and social vulnerability. This suggests that multidisciplinary models of care that aim to manage discordant comorbidities and address psychosocial determinants of health, such as renal supportive care, may play an important role in reducing inpatient admissions in this population.

Abstract Background High blood pressure is the most significant risk factor for the development and progression of chronic kidney disease (CKD). Lowering blood pressure is a goal to prevent CKD progression. This study of adults with CKD who have hypertension aimed to determine blood pressure control rates and the treatment patterns of hypertension and to explore factors associated with control of hypertension. Methods This cross-sectional study included all non-dialysis people with CKD stages 3A to 5 under nephrology care in three public renal clinics in Queensland, who joined the CKD.QLD registry from May 2011 to Dec 2015 and had a history of hypertension. Demographic information, other health conditions, laboratory markers and anti-hypertensive medications in use at consent were extracted from the registry. Results Among 1814 CKD people in these three sites in the registry who were age ≥ 18 years and had CKD stage 3A to 5, 1750 or 96% had a history of hypertension. Of these, the proportion with BP control to 140/90 mmHg) were older age, diabetes, CVD, obesity and severe albuminuria/proteinuria (p

Abstract Background A survival advantage associated with obesity has often been described in dialysis patients. The association of higher body mass index (BMI) with mortality and renal replacement therapy (RRT) in preterminal chronic kidney disease (CKD) patients has not been established. Methods Subjects were patients with pre-terminal CKD who were recruited to the CKD.QLD registry. BMI at time of consent was grouped as normal (BMI 18.5–24.9 kg/m2), overweight (BMI 25–29.9 kg/m2), mild obesity (BMI 30–34.9 kg/m2) and moderate obesity+ (BMI ≥ 35 kg/m2) as defined by WHO criteria. The associations of BMI categories with mortality and starting RRT were analysed. Results The cohort consisted of 3344 CKD patients, of whom 1777 were males (53.1%). The percentages who had normal BMI, or were overweight, mildly obese and moderately obese+ were 18.9, 29.9, 25.1 and 26.1%, respectively. Using people with normal BMI as the reference group, and after adjusting for age, socio-economic status, CKD stage, primary renal diagnoses, comorbidities including cancer, diabetes, peripheral vascular disease (PVD), chronic lung disease, coronary artery disease (CAD), and all other cardiovascular disease (CVD), the hazard ratios (HRs, 95% CI) of males for death without RRT were 0.65 (0.45–0.92, p = 0.016), 0.60 (0.40–0.90, p = 0.013), and 0.77 (0.50–1.19, p = 0.239) for the overweight, mildly obese and moderately obese+. With the same adjustments the hazard ratios for death without RRT in females were 0.96 (0.62–1.50, p = 0.864), 0.94 (0.59–1.49, p = 0.792) and 0.96 (0.60–1.53, p = 0.865) respectively. In males, with normal BMI as the reference group, the adjusted HRs of starting RRT were 1.15 (0.71–1.86, p = 0.579), 0.99 (0.59–1.66, p = 0.970), and 0.95 (0.56–1.61, p = 0.858) for the overweight, mildly obese and moderately obese+ groups, respectively, and in females they were 0.88 (0.44–1.76, p = 0.727), 0.94 (0.47–1.88, p = 0.862) and 0.65 (0.33–1.29, p = 0.219) respectively. Conclusions More than 80% of these CKD patients were overweight or obese. Higher BMI seemed to be a significant “protective” factor against death without RRT in males but there was not a significant relationship in females. Higher BMI was not a risk factor for predicting RRT in either male or female patients with CKD.

Background: Acute kidney injury (AKI) contributes to and complicates chronic kidney disease (CKD). We describe AKI documented in hospital encounters in patients with CKD from the CKD Queensland registry. Study Design: A retrospective cohort study during 2011 to 2016. Setting & Participants: Participants had been admitted to a hospital in Queensland. Predictors: AKI was identified from International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, Australian Modification codes. Outcomes: All-cause mortality with or without kidney replacement therapy (KRT), start-up KRT and maintenance KRT, costs of care. Analytical Approach: Time to outcomes for those with versus without AKI was evaluated using Cox regression models. Mann-Whitney test was used to compare number of admissions, hospitalized days and costs by AKI status. Results: Among 6,365 patients followed up for up to 5.4 years, 2,199 (35%) had 4,711 hospital encounters with an AKI diagnosis. Those with AKI were older (68 vs 64 years old), were more often men (36.7% vs 32.2%; P < 0.001), had more advanced CKD stages (stage 3b, 34%; stage 4, 35%; and stage 5, 10%), had more admissions (12 vs 5; P < 0.001), and stayed in the hospital longer (56 vs 14 days; P < 0.001) than those without AKI. Almost 90% of AKI admissions were through the emergency department. Of those with AKI, 554 (25%) subsequently died without any form of KRT and 285 (13%) started KRT, compared with 282 (6.8%) who died and 315 (7.6%) who started KRT among those without AKI; P < 0.001 for each. Adjusted for other significant factors, hazard ratios for all deaths or death without KRT were 2.95 (95% CI, 2.56-3.39; P < 0.001) and 3.02 (95% CI, 2.60-3.51; P < 0.001), respectively, in patients with AKI relative to those without AKI. The hazard ratio for all KRT was 1.40 (95% CI, 1.18-1.66; P < 0.001), and for maintenance KRT was 1.21 (95% CI, 0.98-1.48; P = 0.07). Mean total hospital cost in patients with AKI was more than triple that of patients with no AKI (A $93,042 vs A $30,778; P < 0.001). Limitations: These findings may not be generalizable to CKD populations from the general community or in other health care environments. Conclusions: AKI is associated with strikingly increased deaths, increased rates of KRT, and higher hospital costs. Index Words: Acute kidney injury, chronic kidney disease, all-cause mortality, kidney replacement therapy, dialysis

RNA interference (RNAi) is a sequence-specific gene silencing mechanism that holds great promise for effective management of agricultural pests. Previous studies have shown that the efficacy of RNAi varies among different insect species, which limits its wide spread application in the field of crop protection. In this study, we identified and characterized six core RNAi pathway genes including OfDicer1, OfDicer2, OfR2D2, OfAgo1, OfAgo2, and OfAgo3 from the transcriptomic database of the Asian corn borer (Ostrinia furnacalis). Domain analysis showed that the six deduced proteins contained the necessary functional domains. Insect developmental stage- and tissue-specific expression analysis showed that five genes were expressed in all the stages and tissues examined except OfAgo3, which showed low expression in larvae, and high expression in pupae and adults and in the midgut. RT-qPCR was performed to examine the response of these six genes to exogenous double-stranded RNA (dsRNA). Interestingly, the transcript levels of OfDicer2 and OfAgo2 were significantly enhanced after the injection of dsEGFP at different time points and tissues investigated. Consequently, the RNAi efficiency in targeting the insect endogenous genes can be greatly enhanced in the hemolymph or midgut. Taken together, our investigations suggest that RNAi efficiency can be enhanced by pre-injection of dsRNA to induce the RNAi core machinery genes, which could be a useful strategy to improving RNAi efficiency for studying gene functions under laboratory conditions.

Apolipophorins are carrier proteins that bind lipids and mediate their transport from tissue to tissue in animals. Apolipophorin I and II (apoLp-II/I) are the major apolipophorins in insects. The implication of apoLp-II/I in cuticle lipid-barrier formation in insects has not been addressed to date. In the present study, we investigated the function of apoLp-II/I in the migratory locust Locusta migratoria (LmapoLp-II/I). During the development of fifth instar nymphs, LmapoLp-II/I transcript levels increased until mid-instar, and then decreased gradually until molting to the adult stage. We found that LmapoLp-II/I was predominately expressed in the fat body and the integument including oenocytes and epidermal cells. Immunodetection experiments revealed that LmapoLp-I mainly localized in the cytoplasm of oenocytes and epidermal cells. Silencing of LmapoLp-II/I caused molting defects in nymphs. Importantly, RNA interference against LmapoLp-II/I resulted in a significant decrease in the content of cuticle surface lipids including alkanes and methyl alkanes. Cuticular permeability was significantly enhanced in these nymphs in Eosin Y penetration assays. By consequence, desiccation resistance and insecticide tolerance of dsLmapoLp-II/I-treated locusts were reduced. Taken together, our results indicate that LmapoLp-II/I is involved in the transport and deposition of surface-cuticular lipids that are crucial for maintaining normal cuticle barrier function in L. migratoria.

Tudor family proteins exist in all eukaryotic organisms and play a role in many cellular processes by recognizing and binding to proteins with methylated arginine or lysine residues. TDRD5, a member of Tudor domain-containing proteins (TDRDs), has been implicated in the P-element-induced wimpy testis-interacting RNA (piRNA) pathway and germ cell development in some model species, but little is known about its function in other species. Therefore, we identified and characterized LmTDRD5, the TDRD5 ortholog in Locusta migratoria, a hemimetabolous pest. The LmTdrd5 gene has 19 exons that encode a protein possessing a single copy of the Tudor domain and three LOTUS domains at its N-terminus. qRT-PCR analysis revealed a high LmTdrd5 expression level in genital glands. Using RNA interference, LmTdrd5 knockdown in males led to a lag in meiosis phase transition, decreased spermatid elongation and sperm production, and downregulated the expression of the two germ cell-specific transcription factors, LmCREM and LmACT, as well as the sperm tail marker gene LmQrich2.LmTdrd5 knockdown in females reduced the expression levels of vitellogenin (Vg) and Vg receptor (VgR) and impaired ovarian development and oocyte maturation, thus decreasing the hatchability rate. These results demonstrate that LmTdrd5 is essential for germ cell development and fertility in locusts, indicating a conserved function for TDRD5.

The American cockroach (Periplaneta americana) is an hemimetabolous insect with rapid growth, high fecundity, and remarkable tissue-regeneration capability. Here Li et al sequence its 3.38-Gb genome and perform the functional studies, yielding insights into its environmental adaptation and developmental plasticity.

Small interfering RNAs (siRNAs) are non-coding RNAs with a length of 21~23 nucleotides (nt) and present in almost all eukaryotes. The formation of siRNA is a highly conserved post-transcriptional gene-silencing mechanism mediated by key proteins, including Dicer2, Argonaute2 (Ago2) and R2D2. R2D2 has been identified as a double-stranded RNA (dsRNA)-binding protein and reported as an integral component of the siRNA pathway in Drosophila. However, the involvement of R2D2 in the siRNA pathway of Locusta migratoria is still unknown. In the present study, we identified an LmR2D2 gene from the transcriptome of L. migratoria. It consists of a 954-bp open reading frame that encodes a protein of 318 amino acid residues. Further sequence analysis revealed that LmR2D2 possesses two tandem dsRNA-binding domains (dsRBD) at the N-terminus. Analysis of the developmental expression profile of LmR2D2 indicated that its transcript level was stable in third-instar nymphs of L. migratoria, whereas the tissue-dependent expression profile exhibited high levels of expression of LmR2D2 in the testis and ovary. When LmR2D2 was silenced by RNAi, the RNAi efficiency against Lmβ-tubulin as a marker gene was significantly diminished, as indicated by the 37.7% increased Lmβ-tubulin transcript level. Additionally, the prokaryotic expression system was used to obtain the LmR2D2 supernatant protein. By incubating the LmR2D2 protein with biotin-dsRNA, we found that LmR2D2 can bind to dsRNA in vitro, which supports our conclusion that LmR2D2 plays an essential role in the siRNA pathway of L. migratoria.

Unreasonable human activities may cause the accumulation of heavy metals (HMs) in the agricultural soil, which will ultimately threaten the quality of soil environment, the safety of agricultural products, and human health. Therefore, the accumulation characteristics, potential sources, and health risks of HMs in agricultural soils in China’s subtropical regions were investigated. The mean Hg, Cu, Zn, Pb, and Cd concentrations of agricultural soil in Jinhua City have exceeded the corresponding background values of Zhejiang Province, while the mean concentrations of determined 8 HMs were less than their corresponding risk-screening values for soil contamination of agricultural land in China. The spatial distribution of As, Cr, Ni, Cu, and Pb were generally distributed in large patches, and Hg, Zn, and Cd were generally sporadically distributed. A positive definite matrix factor analysis (PMF) model had better performance than an absolute principal component–multiple linear regression (APCS-MLR) model in the identification of major sources of soil HMs, as it revealed higher R2 value (0.81–0.99) and lower prediction error (−0.93–0.25%). The noncarcinogenic risks (HI) of the 8 HMs to adults and children were within the acceptable range, while the carcinogenic risk (RI) of children has exceeded the safety threshold, which needs to be addressed by relevant departments. The PMF based human health risk assessment model indicated that industrial sources contributed the highest risk to HI (32.92% and 30.47%) and RI (60.74% and 61.5%) for adults and children, followed by agricultural sources (21.34%, 29.31% and 32.94% 33.19%). Therefore, integrated environmental management should be implemented to control and reduce the accumulation of soil HMs from agricultural and industrial sources.

The impact of human interference on the ecological environment has attracted a significant amount of attention. In this study, hemeroby index (HI) was constructed to quantify the degree of human disturbance, and the relationship between HI and landscape pattern index was explored in a newly metropolitan area. The main objectives of this study were to analyze the temporal and spatial characteristics of landscape pattern and human disturbance in the process of urbanization of county-level cities in China, and to explore the relationship between the landscape pattern index and human disturbance under different disturbance intensity. The conclusions showed that: (1) the degree of human interference in the new area is on the rise, with a slow increase from 1980 to 2010, but since 2010, human interference has increased significantly. The diffusion of human disturbance intensity has obvious spatial directivity, spreading from east to west. (2) The impact of human activities on landscape pattern is shown as increasing fragmentation and increasing number of landscape types. With the enhancement of human activities, the heterogeneity and fragmentation of landscape types in the region reach their highest points. With the continuous increase of human activities, on a certain scale, the landscape types will gradually tend to be the same, and the same type of landscape patches will become one piece and tend to be integrated. This phenomenon is particularly obvious at the patch type level. (3) There is an inflection point value between human disturbance and landscape pattern index in landscape or patch type. On both sides of the inflection point value, the landscape pattern parameters and human disturbance have obvious opposite trends. (4) In the low interference range (1 ≤ HI < 4), with the increase of human interference, more heterogeneous structures (shown in the increase of SHDI) are brought to the landscape, there is more landscape fragmentation (shown in the decrease of LPI, CONTRACT, and AI), and the patch shape and landscape structure tend to be complex (shown in the increase of LSI, SQP, ED, and other indexes); in the high interference range (4 ≤ HI ≤ 7), due to human intervention, the increase of LPI, contract, and AI indicates that intense human activities turn the landscape into a broken and scattered structure and tend to be consistent and homogeneous. LSI, SQP, and ED were negatively correlated with HI at this stage, indicating that with the enhancement of human activities, the complexity of landscape shape decreased.

Abstract Background Robust and defensible clinical assessments attempt to minimise differences in student grades which are due to differences in examiner severity (stringency and leniency). Unfortunately there is little evidence to date that examiner training and feedback interventions are effective; “physician raters” have indeed been deemed “impervious to feedback”. Our aim was to investigate the effectiveness of a general practitioner examiner feedback intervention, and explore examiner attitudes to this. Methods Sixteen examiners were provided with a written summary of all examiner ratings in medical student clinical case examinations over the preceding 18 months, enabling them to identify their own rating data and compare it with other examiners. Examiner ratings and examiner severity self-estimates were analysed pre and post intervention, using non-parametric bootstrapping, multivariable linear regression, intra-class correlation and Spearman’s correlation analyses. Examiners completed a survey exploring their perceptions of the usefulness and acceptability of the intervention, including what (if anything) examiners planned to do differently as a result of the feedback. Results Examiner severity self-estimates were relatively poorly correlated with measured severity on the two clinical case examination types pre-intervention (0.29 and 0.67) and were less accurate post-intervention. No significant effect of the intervention was identified, when differences in case difficulty were controlled for, although there were fewer outlier examiners post-intervention. Drift in examiner severity over time prior to the intervention was observed. Participants rated the intervention as interesting and useful, and survey comments indicated that fairness, reassurance, and understanding examiner colleagues are important to examiners. Conclusions Despite our participants being receptive to our feedback and wanting to be “on the same page”, we did not demonstrate effective use of the feedback to change their rating behaviours. Calibration of severity appears to be difficult for examiners, and further research into better ways of providing more effective feedback is indicated.

Changes of body color have important effects for animals in adapting to variable environments. The migratory locust exhibits body color polyphenism between solitary and gregarious individuals, with the former displaying a uniform green coloration and the latter having a prominent pattern of black dorsal and brown ventral surface. However, the molecular mechanism underlying the density-dependent body color changes of conspecific locusts remain largely unknown. Here, we found that upregulation of β-carotene-binding protein promotes the accumulation of red pigment, which added to the green color palette present in solitary locusts changes it from green to black, and that downregulation of this protein led to the reverse, changing the color of gregarious locusts from black to green. Our results provide insight that color changes of locusts are dependent on variation in the red β-carotene pigment binding to βCBP. This finding of animal coloration corresponds with trichromatic theory of color vision.

Heavy metal (HM) accumulation in farmland soil can be transferred to the human body through the food chain, posing a serious threat to human health. Exploring the environmental risk and safe utilization zoning of soil HMs in farmland can provide the basis for the formulation of effective control strategies. Soil samples from typical subtropical farmland were collected in Jinhua City and analyzed for HMs (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn). The objective of this study was to explore the spatial distribution and environmental risk of soil HMs, and then divide the safe utilization area of soil HMs of farmland in Jinhua City. The results showed that the mean concentrations of soil HMs were, in descending order: Zn (76.05 mg kg−1) > Cr (36.73 mg kg−1) > Pb (32.48 mg kg−1) > Cu (18.60 mg kg−1) > Ni (11.95 mg kg−1) > As (6.37 mg kg−1) > Cd (0.18 mg kg−1) > Hg (0.11 mg kg−1), and all determined soil HMs did not exceed the risk screening values for soil contamination of agricultural land of China. The fitted semi-variogram showed that the spatial autocorrelation of Cd, Hg, Pb, and Zn was weak, with island-shaped distribution, while As, Cr, Cu, and Ni had medium spatial autocorrelation, with strip-shaped and island-shaped distribution. The hot spot analysis and environmental risk probability showed that the environmental risks of As, Cd, Cu, Pb, Zn, and Cu were relatively high, whereas those of Cr, Hg, and Ni were relatively low. Safe utilization zones and basic safe utilization zones accounted for 89.35% and 8.58% of the total farmland area in Jinhua, respectively, and only a small part of the farmland soil was at risk of use.

In recent years, atmospheric PM2.5 pollution in China has become increasingly severe and exploring the relationships among its influencing factors is important in the prevention and control of air pollution. Although previous studies have identified complexity in variations in PM2.5 concentrations and recognized the interaction of multiple factors, little quantitative information is available on the evolution of the relationships among these factors, their spatial heterogeneity, and the multiscale interactions between them. In this study, geographical detector and multiscale geographically weighted regression models have been used to explore the multiscale interactions among natural and socioeconomic factors and PM2.5 concentration in China over the period 2000–2015. The results indicate that the relationship between natural factors and PM2.5 concentration is stronger than that for socioeconomic factors. The type of interaction between each factor is dominated by bivariate and nonlinear enhancement, exhibiting strong interactions between natural factors and anthropogenic factors. Although the effect of each factor on PM2.5 is complex, the relative influence of both human activities and social factors is shown to have gradually increased over time and population, agriculture, urbanization, and socioeconomic activities in general make important contributions to PM2.5. In addition, the scale of effects related to natural factors is smaller and more stable compared to the influence of human activities during the period 2000-2015. There are significant differences in the way natural factors and socioeconomic factors affect PM2.5, and there is strong non-stationarity of spatial relationships. Factors associated with topography, vegetation (NDVI), climate (temperature), natural sources, and agricultural activity are shown to be important determinants of PM2.5 across China and warrant significant attention in terms of managing atmospheric pollution. The study demonstrates that spatial differences in the direction, intensity, and scale of each factor should be accounted for to improve prevention and control measures and alleviate regional PM2.5 pollution.

DEAD-box protein 6 (DDX6) is a member of the DDX RNA helicase family that exists in all eukaryotes. It has been extensively studied in yeast and mammals and has been shown to be involved in messenger ribonucleoprotein assembly, mRNA storage, and decay, as well as in miRNA-mediated gene silencing. DDX6 participates in many developmental processes but the biological function of DDX6 in insects has not yet been adequately addressed. Herein, we characterized the LmDDX6 gene that encodes the LmDDX6 protein in Locusta migratoria, a global, destructive pest. LmDDX6 possesses five motifs unique to the DDX6 subfamily. In the phylogenetic tree, LmDDX6 was closely related to its orthologs in Apis dorsata and Zootermopsis nevadensis. RT-qPCR data revealed high expression of LmDDX6 in the ovary, muscle, and fat body, with a declining trend in the ovary after adult ecdysis. LmDDX6 knockdown downregulated the expression levels of the juvenile hormone receptor Met, and genes encoding Met downstream targeted Grp78-1 and Grp78-2, reduced LmVg expression, and impaired ovary development and oocyte maturation. These results demonstrate that LmDDX6 plays an essential role in locust female reproduction and, thus, could be a novel target for locust biological control.

Variable RNA interference (RNAi) efficiencies limit RNAi-based pest management strategies for many pests. Previous efforts to understand mechanisms contributing to low RNAi efficiency indicate that double-stranded RNA (dsRNA) is degraded in the European corn borer (ECB), Ostrinia nubilalis, due to nuclease activity. To investigate the contribution of dsRNA-degrading endonucleases (dsRNases) and lepidopteran-specific RNAi efficiency-related nucleases (REases) to dsRNA instability and low RNAi efficiency in ECB, five complementary DNAs putatively encoding four dsRNases (OndsRNase1, 2, 3, and 4) and one REase (OnREase) were sequenced. Characterization of these transcripts revealed that substrate specificity might vary among the four dsRNases due to different amino acid combinations in the substrate-binding sites. Gene expression analysis indicated that OndsRNase2 and OnREase were highly expressed in the larval gut, and OndsRNase1 showed the highest expression in hemolymph, especially in older developmental stages. Transcript level analysis after dsRNA exposure revealed that expression of OnREase rapidly increased upon dsRNA ingestion or injection, whereas OndsRNase4 expression only increased after long-term ingestion of dsRNA. While the biological function of these nucleases remains to be verified, our results suggest that OnREase and OndsRNase2, and OndsRNase1 and OndsRNase4 may be responsible for degradation of dsRNAs in the ECB gut and hemolymph, respectively, thereby contributing to low RNAi efficiency.

Chitin synthase and chitinase play crucial roles in chitin biosynthesis and degradation during insect molting. Silencing of Dicer-1 results in reduced levels of mature miRNAs and severely blocks molting in the migratory locust. However, the regulatory mechanism of miRNAs in the molting process of locusts has remained elusive. In this study, we found that in chitin metabolism, two crucial enzymes, chitin synthase (CHS) and chitinase (CHT) were regulated by miR-71 and miR-263 during nymph molting. The coding sequence of CHS1 and the 3'-untranslated region of CHT10 contain functional binding sites for miR-71 and miR-263, respectively. miR-71/miR-263 displayed cellular co-localization with their target genes in epidermal cells and directly interacted with CHS1 and CHT10 in the locust integument, respectively. Injections of miR-71 and miR-263 agomirs suppressed the expression of CHS1 and CHT10, which consequently altered chitin production of new and old cuticles and resulted in a molting-defective phenotype in locusts. Unexpectedly, reduced expression of miR-71 and miR-263 increased CHS1 and CHT10 mRNA expression and led to molting defects similar to those induced by miRNA delivery. This study reveals a novel function and balancing modulation pattern of two miRNAs in chitin biosynthesis and degradation, and it provides insight into the underlying molecular mechanisms of the molting process in locusts.

Heat shock proteins (Hsps) are highly conserved molecular chaperones that are synthesized in response to stress. In this study, we cloned the full-length sequences of the Grp78 (glucose-regulated protein 78), Hsp70, Hsp90, and Hsp40 genes from the Chinese rice grasshopper Oxya chinensis. The full-length cDNA sequences of OcGrp78, OcHsp70, OcHsp90, and OcHsp40 contain open reading frames of 1947, 1920, 2172, and 1042 bp that encode proteins of 649, 640, 724, and 347 amino acids, respectively. Fluorescent real-time quantitative PCR (RT-qPCR) was performed to quantify the relative transcript levels of these Hsp genes in different tissues and developmental stages. The mRNAs encoding these four Hsp genes were present at all developmental stages and in all tissues examined but were expressed at varying levels. Additionally, we investigated the mRNA expression profiles of these four Hsps in O. chinensis subjected to Cadmium (Cd) stress. OcGrp78, OcHsp70, OcHsp90, and OcHsp40 mRNA expression was induced under acute Cd stress; the levels reached a maximum within a short time (6 h), were reduced significantly at 12 h, and were lowered to or below control levels by 48 h. Regarding induction efficiency, OcHsp70 was the most sensitive gene to acute Cd stress. Chronic Cd exposure showed that dietary Cd treatment induced increased OcGrp78, OcHsp90, and OcHsp40 expression. However, dietary Cd induced a significant reduction of OcHsp70 expression. In the period tested, no significant difference in the mortality of the grasshoppers was observed. Our results suggest that these four Hsps genes, especially OcHsp70, are sensitive to acute Cd stress and could be used as molecular markers for toxicology studies. However, our results also indicate that OcHsp70 is not suitable for use as a molecular marker of chronic Cd contamination.

Antioxidant enzymes play a major role in defending against oxidative damage by copper. However, few studies have been performed to determine which antioxidant enzymes respond to and are necessary for copper detoxification. In this study, we examined both the activities and mRNA levels of SOD, CAT, and GPX under excessive copper stress in Caenorhabditis elegans, which is a powerful model for toxicity studies. Then, taking advantage of the genetics of this model, we assessed the lethal concentration (LC50) values of copper for related mutant strains. The results showed that the SOD, CAT, and GPX activities were significantly greater in treated groups than in controls. The mRNA levels of sod-3, sod-5, ctl-1, ctl-2, and almost all gpx genes were also significantly greater in treated groups than in controls. Among tested mutants, the sod-5, ctl-1, gpx-3, gpx-4, and gpx-6 variants exhibited hypersensitivity to copper. The strains with SOD or CAT over expression were reduced sensitive to copper. Mutations in daf-2 and age-1, which are involved in the insulin/insulin-like growth factor-1 signaling pathway, result in reduced sensitivity to stress. Here, we showed that LC50 values for copper in daf-2 and age-1 mutants were significantly greater than in N2 worms. However, the LC50 values in daf-16;daf-2 and daf-16;age-1 mutants were significantly reduced than in daf-2 and age-1 mutants, implying that reduced copper sensitivity is influenced by DAF-16-related functioning. SOD, CAT, and GPX activities and the mRNA levels of the associated copper responsive genes were significantly increased in daf-2 and age-1 mutants compared to N2. Additionally, the activities of SOD, CAT, and GPX were greater in these mutants than in N2 when treated with copper. Our results not only support the theory that antioxidant enzymes play an important role in copper detoxification but also identify the response and the genes involved in these processes.

Metallothioneins (MTs) are small, cysteine-rich, heavy metal-binding proteins involved in metal homeostasis and detoxification in living organisms. In the present study, we cloned two MT genes (OcMT1 and OcMT2) from Oxya chinensis, analyzed the expression patterns of the OcMT transcripts in different tissues and at varying developmental stages using real-time quantitative PCR (RT-qPCR), evaluated the functions of these two MTs using RNAi and recombinant proteins in an E. coli expression system. The full-length cDNAs of OcMT1 and OcMT2 encoded 40 and 64 amino acid residues, respectively. We found Cys-Cys, Cys-X-Cys and Cys-X-Y-Z-Cys motifs in OcMT1 and OcMT2. These motifs might serve as primary chelating sites, as in other organisms. These characteristics suggest that OcMT1 and OcMT2 may be involved in heavy metal detoxification by capturing the metals. Two OcMT were expressed at all developmental stages, and the highest levels were found in the eggs. Both transcripts were expressed in all eleven tissues examined, with the highest levels observed in the brain and optic lobes, followed by the fat body. The expression of OcMT2 was also relatively high in the ovaries. The functions of OcMT1 and OcMT2 were explored using RNA interference (RNAi) and different concentrations and treatment times for the three heavy metals. Our results indicated that mortality increased significantly from 8.5% to 16.7%, and this increase was both time- and dose-dependent. To evaluate the abilities of these two MT proteins to confer heavy metal tolerance to E. coli, the bacterial cells were transformed with pET-28a plasmids containing the OcMT genes. The optical densities of both the MT-expressing and control cells decreased with increasing concentrations of CdCl2. Nevertheless, the survival rates of the MT-overexpressing cells were higher than those of the controls. Our results suggest that these two genes play important roles in heavy metal detoxification in O. chinensis.

Carboxylesterases (CarEs) belong to a superfamily of metabolic enzymes encoded by a number of genes and are widely distributed in microbes, plants and animals including insects. These enzymes play important roles in detoxification of insecticides and other xenobiotics, degradation of pheromones, regulation of neurodevelopment, and control of animal development. In this study, we characterized a total of 39 full-length cDNAs putatively encoding different CarEs from the migratory locust, Locusta migratoria, one of the most severe insect pests in many regions of the world, and evaluated the role of four CarE genes in insecticide detoxification. Our phylogenetic analysis grouped the 39 CarEs into five different clades including 20 CarEs in clade A, 3 in D, 13 in E, 1 in F and 2 in I. Four CarE genes (LmCesA3, LmCesA20, LmCesD1, LmCesE1), representing three different clades (A, D and E), were selected for further analyses. The transcripts of the four genes were detectable in all the developmental stages and tissues examined. LmCesA3 and LmCesE1 were mainly expressed in the fat bodies and Malpighian tubules, whereas LmCesA20 and LmCesD1 were predominately expressed in the muscles and hemolymph, respectively. The injection of double-stranded RNA (dsRNA) synthesized from each of the four CarE genes followed by the bioassay with each of four insecticides (chlorpyrifos, malathion, carbaryl and deltamethrin) increased the nymphal mortalities by 37.2 and 28.4% in response to malathion after LmCesA20 and LmCesE1 were silenced, respectively. Thus, we proposed that both LmCesA20 and LmCesE1 played an important role in detoxification of malathion in the locust. These results are expected to help researchers reveal the characteristics of diverse CarEs and assess the risk of insecticide resistance conferred by CarEs in the locust and other insect species.

Glutathione S-transferases (GSTs) are multifunctional enzymes that are involved in the metabolism of endogenous and exogenous compounds and are related to insecticide resistance. The purpose of this study was to provide new information on the molecular characteristics and the positive selection of locust GSTs. Based on the transcriptome database, we sequenced 28 cytosolic GSTs and 4 microsomal GSTs from the migratory locust (Locusta migratoria). We assigned the 28 cytosolic GSTs into 6 classes--sigma, epsilon, delta, theta, omega and zeta, and the 4 microsomal GSTs into 2 subclasses--insect and MGST3. The tissue- and stage-expression patterns of the GSTs differed at the mRNA level. Further, the substrate specificities and kinetic constants of the cytosolic GSTs differed markedly at the protein level. The results of likelihood ratio tests provided strong evidence for positive selection in the delta class. The result of Bayes Empirical Bayes analysis identified 4 amino acid sites in the delta class as positive selection sites. These sites were located on the protein surface. Our findings will facilitate the elucidation of the molecular characteristics and evolutionary aspects of insect GST superfamily.

UDP-N-acetylglucosamine pyrophosphorylases (UAP) function in the formation of extracellular matrix by producing N-acetylglucosamine (GlcNAc) residues needed for chitin biosynthesis and protein glycosylation. Herein, we report two UAP cDNA's derived from two different genes (LmUAP1 and LmUAP2) in the migratory locust Locusta migratoria. Both the cDNA and their deduced amino acid sequences showed about 70% identities between the two genes. Phylogenetic analysis suggests that LmUAP1 and LmUAP2 derive from a relatively recent gene duplication event. Both LmUAP1 and LmUAP2 were widely expressed in all the major tissues besides chitin-containing tissues. However, the two genes exhibited different developmental expression patterns. High expression of LmUAP1 was detected during early embryogenesis, then decreased greatly, and slowly increased before egg hatch. During nymphal development, the highest expression of LmUAP1 appeared just after molting but declined in each inter-molting period and then increased before molting to the next stage, whereas LmUAP2 was more consistently expressed throughout all these stages. When the early second- and fifth-instar nymphs (1-day-old) were injected with LmUAP1 double-stranded RNA (dsRNA), 100% mortality was observed 2 days after the injection. When the middle second- and fifth-instar nymphs (3- to 4-day-old) were injected with LmUAP1 dsRNA, 100% mortality was observed during their next molting process. In contrast, when the insects at the same stages were injected with LmUAP2 dsRNA, these insects were able to develop normally and molt to the next stage successfully. It is presumed that the lethality caused by RNAi of LmUAP1 is due to reduced chitin biosynthesis of the integument and midgut, whereas LmUAP2 is not essential for locust development at least in nymph stage. This study is expected to help better understand different functions of UAP1 and UAP2 in the locust and other insect species.

Glutathione S-transferases (GSTs) play an important role in detoxification of xenobiotics in both prokaryotic and eukaryotic cells. In this study, four GSTs (LmGSTd1, LmGSTs5, LmGSTt1, and LmGSTu1) representing different classes were identified from the migratory locust, Locusta migratoria. These four proteins were heterologously expressed in Escherichia coli as soluble fusion proteins, purified by Ni(2+)-nitrilotriacetic acid agarose column and biochemically characterized. LmGSTd1, LmGSTs5, and LmGSTu1 showed high activities with 1-chloro-2, 4-dinitrobenzene (CDNB), detectable activity with p-nitro-benzyl chloride (p-NBC) and 1, 2-dichloro-4-nitrobenzene (DCNB), whereas LmGSTt1 showed high activity with p-NBC and detectable activity with CDNB. The optimal pH of the locust GSTs ranged between 7.0 to 9.0. Ethacrynic acid and reactive blue effectively inhibited all four GSTs. LmGSTs5 was most sensitive to heavy metals (Cu(2+) and Cd(2+)). The maximum expression of the four GSTs was observed in Malpighian tubules and fat bodies as evaluated by western blot. The nymph mortalities after carbaryl treatment increased by 28 and 12% after LmGSTs5 and LmGSTu1 were silenced, respectively. The nymph mortalities after malathion and chlorpyrifos treatments increased by 26 and 18% after LmGSTs5 and LmGSTu1 were silenced, respectively. These results suggest that sigma GSTs in L. migratoria play a significant role in carbaryl detoxification, whereas some of other GSTs may also involve in the detoxification of carbaryl and chlorpyrifos.

The chemical similarity of cellulose and chitin supports the idea that their corresponding hydrolytic enzymes would bind β-1,4-linked glucose residues in a similar manner. A structural and mutational analysis was performed for the plant cellulolytic enzyme BGlu1 from Oryza sativa and the insect chitinolytic enzyme OfHex1 from Ostrinia furnacalis. Although BGlu1 shows little amino-acid sequence or topological similarity with OfHex1, three residues (Trp(490), Glu(328), Val(327) in OfHex1, and Trp(358), Tyr(131) and Ile(179) in BGlu1) were identified as being conserved in the +1 sugar binding site. OfHex1 Glu(328) together with Trp(490) was confirmed to be necessary for substrate binding. The mutant E328A exhibited a 8-fold increment in K(m) for (GlcNAc)(2) and a 42-fold increment in K(i) for TMG-chitotriomycin. A crystal structure of E328A in complex with TMG-chitotriomycin was resolved at 2.5 Å, revealing the obvious conformational changes of the catalytic residues (Glu(368) and Asp(367)) and the absence of the hydrogen bond between E328A and the C3-OH of the +1 sugar. V327G exhibited the same activity as the wild-type, but acquired the ability to efficiently hydrolyse β-1,2-linked GlcNAc in contrast to the wild-type. Thus, Glu(328) and Val(327) were identified as important for substrate-binding and as glycosidic-bond determinants. A structure-based sequence alignment confirmed the spatial conservation of these three residues in most plant cellulolytic, insect and bacterial chitinolytic enzymes.

Chitinase is an important enzyme responsible for chitin metabolism in a wide range of organisms including bacteria, yeasts and other fungi, nematodes and arthropods. However, current knowledge on chitinolytic enzymes, especially their structures, functions and regulation is very limited. In this study we have identified 20 chitinase and chitinase-like genes in the African malaria mosquito, Anopheles gambiae, through genome-wide searching and transcript profiling. We assigned these genes into eight different chitinase groupings (groups I-VIII). Domain analysis of their predicted proteins showed that all contained at least one catalytic domain. However, only seven (AgCht4, AgCht5-1, AgCht6, AgCht7, AgCht8, AgCht10 and AgCht23) displayed one or more chitin-binding domains. Analyses of stage- and tissue-specific gene expression revealed that most of these genes were expressed in larval stages. However, AgCht8 was mainly expressed in the pupal and adult stages. AgCht2 and AgCht12 were specifically expressed in the foregut, whereas AgCht13 was only expressed in the midgut. The high diversity and complexity of An. gambiae chitinase and chitinase-like genes suggest their diverse functions during different developmental stages and in different tissues of the insect. A comparative genomic analysis of these genes along with those present in Drosophila melanogaster, Tribolium castaneum and several other insect species led to a uniform classification and nomenclature of these genes. Our investigation also provided important information for conducting future studies on the functions of chitinase and chitinase-like genes in this important malaria vector and other species of arthropods.

Chronic kidney disease (CKD) is one of the most common chronic diseases in the western world. In Australia, around 1.7 million Australians aged 18 years and over (about one in ten) have indicators of CKD, and 1.8 million hospitalisations were associated with CKD in 2017–18. There is currently very little understanding of the impact of CKD on health service utilisation and costs. Understanding the disease pathways of CKD and its effects on service utilisation and patient outcomes is essential to predicting the course of the disease in the future, its effects on health services utilisation and capacity to better manage the burden of premature deaths or the need for dialysis that results from CKD. We describe the establishment of a data linkage framework to study hospital admissions of CKD patients in the public renal services in the Australian state of Queensland, and its potential to advance understanding of their course and outcomes. Seven years of retrospective data (2011–2018) on hospital-based health services utilisation were provided by Queensland Health for all 7,341 patients who enrolled in the CKD.QLD Registry up to Jan 2019. The data were supplied from three datasets: the Queensland Hospital Admitted Patient Data Collection, the Queensland Registrar General deaths, and the Activity Based Funding Model Output data. In addition, data were supplied from two cohorts of de-identified patients admitted to hospital in the same interval (22,023 patients each), who were not in the CKD.QLD Registry, the first with CKD and the second without CKD as indicated by International Classification of Diseases and Related Health Problems, Tenth Revision, Australian Modification. The comprehensive and multifaceted data via the data linkage will enable us to identify opportunities for efficiencies in management of patients with CKD and for interventions that improve their outcomes.