Transcriptome analysis reveals the role of Zelda in the regulation of embryonic and wing development of Tribolium castaneum.

Zinc finger protein (Zelda) of Tribolium castaneum (TcZelda) has been showed to play pivotal roles in embryonic development and metamorphosis. However, the regulatory mechanism of TcZelda associated with these physiology processes is unclear. Herein, the developmental expression profile showed that Zelda of T. castaneum was highly expressed in early eggs. Tissue expression profiling revealed that TcZelda was mainly expressed in the larval head and adult ovary of late adults and late larvae. TcZelda knockdown led to a 95% mortality rate in adults. These results suggested that TcZelda is related to the activation of the zygote genome in early embryonic development. Furthermore, 592 differentially expressed genes were identified from the dsZelda treated group. Compared with the control group, altered disjunction (ALD) and AGAP005368-PA (GAP) in the dsZelda group were significantly down-regulated, while TGF-beta, propeptide (TGF) was significantly up-regulated, suggesting that TcZelda may be involved in insect embryonic development. In addition, the expression of Ubx ultrabithorax (UBX), Cx cephalothorax (CX), En engrailed (EN), and two Endocuticle structural glycoprotein sgabd (ABD) genes were significantly down-regulated, suggesting that they may cooperate with TcZelda to regulate the development of insect wings. Additionally, Elongation (ELO), fatty acid synthase (FAS), and fatty acyl-CoA desaturase (FAD) expression was inhibited in dsZelda insects, which could disturb the lipase signaling pathways, thus, disrupting the insect reproductive system and pheromone synthesis. These results may help reveal the function of TcZelda in insects and the role of certain genes in the gene regulatory network and provide new ideas for the prevention and control of T. castaneum.

Response of xenobiotic biodegradation and metabolic genes in Tribolium castaneum following eugenol exposure.

Eugenol, a plant-derived component possessing small side effects, has an insecticidal activity to Tribolium castaneum; however, the underlying molecular mechanisms of eugenol acting on T. castaneum are currently unclear. Here, a nerve conduction carboxylesterase and a detoxifying glutathione S-transferase were significantly inhibited after eugenol exposure, resulting in the paralysis or death of beetles. Then, RNA-sequencing of eugenol-exposed and control samples identified 362 differentially expressed genes (DEGs), containing 206 up-regulated and 156 down-regulated genes. RNA-seq data were validated further by qRT-PCR. GO analysis revealed that DEGs were associated with 1308 GO terms of which the most enriched GO terms were catalytic activity, and integral component of membrane; KEGG pathway analysis showed that these DEGs were distributed in 151 different pathways, of which some pathways associated with metabolism of xenobiotics or drug were significantly enriched, which indicated that eugenol most likely disturbed the processes of metabolism, and detoxication. Moreover, several DEGs including Hexokinase type 2, Isocitrate dehydrogenase, and Cytochrome b-related protein, might participate in the respiratory metabolism of eugenol-exposed beetles. Some DEGs encoding CYP, UGT, GST, OBP, CSP, and ABC transporter were involved in the xenobiotic or drug metabolism pathway, which suggested that these genes of T. castaneum participated in the response to eugenol exposure. Additionally, TcOBPC11/ TcGSTs7, detected by qRT-PCR and RNA-interference against these genes, significantly increased the mortality of eugenol-treated T. castaneum, providing further evidence for the involvement of OBP/GST in eugenol metabolic detoxification in T. castaneum. These results aid eugenol insecticidal mechanisms and provide the basis of insect control.

Aldehyde oxidases mediate plant toxicant susceptibility and fecundity in the red flour beetle, Tribolium castaneum.

Aldehyde oxidases (AOXs) are a group of metabolic enzymes that play critical roles in the degradation of xenobiotics and chemicals. However, the physiological function of this enzyme in insects remains poorly understood. In this study, three TcAOX genes (TcAOX1, TcAOX2, TcAOX3) were identified and characterized from Tribolium castaneum genome. Spatiotemporal expression profiling showed that TcAOX1 expression was most highly expressed at the early pupal stage and was predominantly expressed in the antennae of adults, indicating that TcAOX1 was involved in the degradation of chemical signals; TcAOX2 expression was most highly expressed at the late pupal stage and was mainly expressed in the fat body, epidermis of larvae and adults, respectively; and TcAOX3 expression was in all stages and was primarily expressed in the head of adults. Moreover, the transcripts of TcAOX2 and TcAOX3 were significantly induced after exposure to plant oil, and RNA interference (RNAi) targeting of each of them enhanced the susceptibility of beetles to this plant toxicant, suggesting that these two genes are associated with plant toxicant detoxification. Intriguingly, knockdown of the TcAOX1 led to reductions in female egg-laying but unchanged the hatchability and the development of genital organs, suggesting that this gene may mediate fecundity by effecting the inactivation of chemical signals in T. castaneum. Overall, these results shed new light on the function of AOX genes in insects, and could facilitate the development of research on pest control management.

Odorant binding protein C12 is involved in the defense against eugenol in Tribolium castaneum.

Tribolium castaneum (T. castaneum) is a worldwide pest of stored grain that mainly harms flour, and not only causes serious loss of flour quality but also leads to deterioration of flour quality. Chemical detection plays a key role in insect behavior, and the role of odorant-binding proteins (OBPs) in insect chemical detection has been widely studied. However, the mechanism of OBPs in insect defense against exogenous toxic substances is still unclear. In this study, biochemical analysis showed that eugenol, the active component of A. vulgaris essential oil, significantly induced the expression of the OBP gene OBPC12 from T. castaneum (TcOBPC12). The mortality of late larvae treated with eugenol was higher than that of the control group after RNA interference (RNAi) against TcOBPC12, which indicates that the OBP gene is involved in the eugenol defense mechanism and leads to a decrease in sensitivity to eugenol. Tissue expression profiling showed that the expression of TcOBPC12 in the epidermis, hemolymph, and intestine was higher than in other larval tissues, and TcOBPC12 was expressed mainly in the epidermis, head, and fat body of adults. The developmental expression profile showed that the expression of TcOBPC12 in late eggs, early and late larval stages, and late adult stages was higher than in other developmental stages. These data suggest that TcOBPC12 may be involved in the absorption of exogenous toxic substances by the larvae from T. castaneum. Our results provide a theoretical basis for the metabolism and degradation mechanism of exogenous toxic substances and help explore more potential target genes of insect pests.

[Preliminary study on the expression of cystatin C in primary liver cancer].

OBJECTIVE: To preliminarily investigate the expression of cysteine proteinase inhibitors C (cystatin C) in primary hepatic carcinoma. METHODS: Hepatic tissue samples and peripheral blood samples were collected from 41 cases of primary hepatic carcinoma, 24 cases of cirrhosis and 40 cases of normal control. To primary hepatic carcinoma, three kinds of hepatic tissue samples were harvested, including carcinoma tissue, adjacent non-tumor tissue, and distant normal tissue. The expression levels of cystatin C in hepatic samples and blood samples were measured by immunohistochemistry method and latex enhanced immune turbidimetric method respectively, and the differences of cystatin C expressions were compared in primary hepatic cancer, cirrhosis, and normal control. Furthermore, the relationships of cystatin C expression with tumor size, intrahepatic metastasis, serum AFP level were studied with correlation analysis. RESULTS: The expression of cystatin C was positive, in primary hepatic carcinoma. Part of adjacent non-tumor tissue, and distant normal tissue and cirrhosis tissues had some degree of cyctatin C expression. Wilcoxon test showed that the differences of cyctatin C expression in different hepatic tissues were statistics significance (P < 0.01). The proportion of positive cell, staining intensity, and the product of these two was: carcinoma tissues > adjacent non-tumor tissues> cirrhosis tissues > distant normal tissue. Compared with normal control, primary hepatic carcinoma and cirrhosis both had higher serum cystatin C level (P < 0.001), but there was no difference between hepatic carcinoma and cirrhosis (P = 0.769). The correlation analysis showed that the level of serum cystatin C was not related to serum AFP, tumor size, or intrahepatic metastasis. CONCLUSION: The expression of cystatin C in primary hepatic carcinoma is higher than that of adjacent non-tumor tissue, distant normal tissue, and cirrohsis tissue. The serum cystatin C level of primary hepatic carcinoma is higher than that of normal control.

[Application of glomerular filtration rate prediction formulae in diabetic patients].

OBJECTIVE: To compare the predictive performances of glomerular filtration rate (GFR) prediction formulae based on serum crea level in diabetic patients and to determine their clinical application values. METHODS: Fasting serum crea of 125 diabetic patients in Chengdu were detected. 99mTc-DTPA clearance rate was used as the reference test (rGFR). The eGFR was obtained using different formulae (aMDRD and CKD-EPI formula in this study). The bias, precision, accuracy and diagnostic sensitivity of the two formulae were compared. ROC curve analyses were performed with different diagnostic boundary points [rGFR < S90 or < 60 mL/(min x 1.73(2))]. RESULTS: Significant differences between eGFR and rGFR were found with both formulae (P < 0.05). There were no significant differences in the predict performance between the two formulae in terms of bias, precision and accuracy within 30% and 50%. Two cases with higher than 90 mL/(min x 1.732) rGFR were identified as outliers using aMDRD formula according to the eGFR-rGFR scatterplot analysis. The ROC curve analysis showed that the AUC were in the range between 0.8 and 0.9. The AUC approached 0.9 when proteinuria was taken into consideration for both formulae, and this involved a significant improvement (P < 0.05). CONCLUSION: Both aMDRD and CKD-EPI formulae predict eGFR accurately in diabetic patients. However, the CKD-EPI formula may have better stability in predicting eGFR in patients at an early stage of renal injury. Combined use of proteinuria may improve the diagnostic performance of eGFR prediction formulae. [Key words] Diabetes Glomerular filtration rate aMDRD CKD-EPI

Boosting Photocatalytic Water Oxidation on Photocatalysts with Ferroelectric Single Domains.

Ferroelectric materials are considered as promising photocatalysts due to their efficient charge separation via a polarization-induced built-in electric field. However, the polydomain structures hinder spatial charge separation and transfer due to the cancellation of polarization vectors in the domains. In this work, taking BiFeO3 (BFO) as a prototype, single-domain BFO nanosheets with visible-light absorption are prepared, as evident by piezoresponse force microscopy (PFM), spatially resolved surface photovoltage spectroscopy (SRSPS), and photodeposition experiments. The single-domain BFO nanosheets show nine times activity in photocatalytic water oxidation reaction under visible-light irradiation, compared with that of the polydomain BFO particles. With the asymmetric driving force for charge separation in a single domain, selective deposition of cocatalysts further enhances the photocatalytic activity of single-domain ferroelectric BFO nanosheets. These results demonstrate the role of the single-domain structure in constructing the driving force of charge separation in ferroelectric photocatalysts. The fabrication of single-domain structures in ferroelectric photocatalysts to achieve enhanced photocatalytic activity offers a path to efficiently utilize the photogenerated charges in solar energy conversion.

[Estimating glomerular filtration rate based on serum cystatin C].

OBJECTIVE: To develop an estimating formula for glomerular filtration Rate (GFR) based on serum cystatin C in patients with chronic kidney disease (CKD). METHODS: Clinical characteristics of 242 CKD patients were collected. The patients were randomly divided into modeling group and model validation group. The rGFR obtained from 99mTc-DTPA clearance rate was used as a reference value of GFR. s-cystatin C was detected by latex enhanced immunoturbidimetric method. Preliminary linear regression analysis followed by multiple linear regression were performed to investigate the association between s-cystatin C and rGFR. The validity of the estimation formula was tested in the model validation group in comparison with Hoek formula and Orebro formula. RESULTS: With standardised countdown conversion, s-cystatin showed linear correlation with rGFR, with a correlation coefficient of 0.773. The multiple correlation coefficient, determination coefficient, adjusted R square and std. error of the estimation model were 0.863, 0.745, 0.742, and 0.207, respectively. The residuals P-P probability plot analysis showed that the model residuals fitted into normal distribution with homogeneity of variance. Theeformula was: eGFR = 67/s-cystatin C +3. No significant difference was found between the distribution of eGFR and rGFR. Our formula had an accuracy of 30% and 50%, which were no less than those obtained from Hoek formula and Orebro formula. The new formula also had acceptable bias and high precision. The Bland-Altman analysis and ROC curve analysis showed good applicability of the new formula. CONCLUSION: The GFR prediction formula we established has a good prediction performance as comparised with other formulae, which could be used in measuring GFR in CKD patients.

[Source of variations of serum urea levels and consideration of reference interval in urban Chengdu].

OBJECTIVE: To determine the serum Urea levels in healthy adults living in urban Chengdu and to identify factors that influence the serum urea levels for the purpose of establishing reference interval. METHODS: Serum urea levels were determined in 17 787 healthy adults in urban Chengdu who underwent physical examinations. The characteristics of distribution of serum urea levels in the population and its relationships with liver function, renal function, serum glucose, and serum lipid were analyzed. RESULTS: Increased Crea, Uric, Glu, and HDL-C levels and decreased Glb level were associated with increased serum urea levels, which was independent of the impact of sex and age. The association between serum urea and Crea, Glu, and HDL-C existed in normal healthy adults. Men had higher urea levels than women. Regardless of gender, serum urea increased with age (with a cut off point at 30, 50, 60 and 70 years). CONCLUSION: Serum urea levels in healthy adults living in urban Chengdu vary in different gender and age groups. Serum urea levels are associated with serum Crea, Glu, the HDL-C levels. It is necessary to establish gender and age-specific reference intervals for serum urea.