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A heterodimeric complex of two nuclear receptors, the ecdysone receptor (ECR) and ultraspiracle (USP), transduces 20-hydroxyecdysone (20E) signaling to modulate insect growth and development. Here, we aimed to determine the relationship between ECR and 20E during larval metamorphosis and also the specific roles of ECR during larval–adult transition in Apis mellifera. We found that ECR gene expression peaked in the 7-day-old larvae, then decreased gradually from the pupae stage. 20E slowly reduced food consumption and then induced starvation, resulting in small-sized adults. In addition, 20E induced ECR expression to regulate larval development time. Double-stranded RNAs (dsRNAs) were prepared using common dsECR as templates. After dsECR injection, larval transition to the pupal stage was delayed, and 80% of the larvae showed prolonged pupation beyond 18 h. Moreover, the mRNA levels of shd, sro, nvd , and spo , and ecdysteroid titers were significantly decreased in ECR RNAi larvae compared with those in GFP RNAi control larvae. ECR RNAi disrupted 20E signaling during larval metamorphosis. We performed rescuing experiments by injecting 20E in ECR RNAi larvae and found that the mRNA levels of ECR, USP, E75, E93 , and Br-c were not restored. 20E induced apoptosis in the fat body during larval pupation, while RNAi knockdown of ECR genes reduced apoptosis. We concluded that 20E induced ECR to modulate 20E signaling to promote honeybee pupation. These results assist our understanding of the complicated molecular mechanisms of insect metamorphosis. [ABSTRACT FROM AUTHOR]

Aims Chronic stress is a well-known risk factor for the development of hypertension. However, the underlying mechanisms remain unclear. Corticotropin-releasing hormone (CRH) neurons in the central nucleus of the amygdala (CeA) are involved in the autonomic responses to chronic stress. Here, we determined the role of CeA-CRH neurons in chronic stress-induced hypertension. Methods and results Borderline hypertensive rats (BHRs) and Wistar-Kyoto (WKY) rats were subjected to chronic unpredictable stress (CUS). Firing activity and M-currents of CeA-CRH neurons were assessed, and a CRH-Cre-directed chemogenetic approach was used to suppress CeA-CRH neurons. CUS induced a sustained elevation of arterial blood pressure (ABP) and heart rate (HR) in BHRs, while in WKY rats, CUS-induced increases in ABP and HR quickly returned to baseline levels after CUS ended. CeA-CRH neurons displayed significantly higher firing activities in CUS-treated BHRs than unstressed BHRs. Selectively suppressing CeA-CRH neurons by chemogenetic approach attenuated CUS-induced hypertension and decreased elevated sympathetic outflow in CUS-treated BHRs. Also, CUS significantly decreased protein and mRNA levels of Kv7.2 and Kv7.3 channels in the CeA of BHRs. M-currents in CeA-CRH neurons were significantly decreased in CUS-treated BHRs compared with unstressed BHRs. Blocking Kv7 channel with its blocker XE-991 increased the excitability of CeA-CRH neurons in unstressed BHRs but not in CUS-treated BHRs. Microinjection of XE-991 into the CeA increased sympathetic outflow and ABP in unstressed BHRs but not in CUS-treated BHRs. Conclusions CeA-CRH neurons are required for chronic stress-induced sustained hypertension. The hyperactivity of CeA-CRH neurons may be due to impaired Kv7 channel activity, which represents a new mechanism involved in chronic stress-induced hypertension. [ABSTRACT FROM AUTHOR]

Odorant-binding proteins (OBPs) play an important role in odour perception and transport in insects. However, little is known about whether OBPs perform other functions in insects, particularly in Apis cerana cerana. Within this study, an OBP gene (AccOBP10) was isolated and identified from A. c. cerana. Both homology and phylogenetic relationship analyses indicated that the amino acid sequence of AccOBP10 had a high degree of sequence identity with other members of the gene family. Analysis of quantitative real-time PCR (qRT-PCR) showed that AccOBP10 mRNA was expressed at higher levels in the venom gland than in other tissues. The mRNA transcript expression of AccOBP10 was upregulated by low temperature (4°C), hydrogen peroxide (H2O2), pyridaben, methomyl and imidacloprid but downregulated by heat (42°C), ultraviolet light, vitamin C, mercuric chloride, cadmium chloride, paraquat and phoxim. Expression of AccOBP10 under abiotic stress was analysed by western blotting, and the results were consistent with those of qRT-PCR. And as a further study of AccOBP10 function, we demonstrated that knockdown of AccOBP10 by RNA interference could slightly increase the expression levels of some stress-related genes. Collectively, these results suggest that AccOBP10 is mainly involved in the response to stress conditions. [ABSTRACT FROM AUTHOR]

Selenium (Se), as an essential micronutrient, has been demonstrated to play an important role in life activities. In this study, we studied the effects of sucrose solutions containing sodium selenite on Apis mellifera (L.). We obtained the appropriate level of sodium selenite for A. mellifera by determining the life span by lab rearing, and then, we studied the effects of sodium selenite on antioxidant activity, phenol oxidase activity, development of the hypopharyngeal gland, Se content of body tissues and royal jelly (RJ), and related gene transcription levels for a bee colony. The results of lab rearing showed that a concentration of 0.57 mg/liter sodium selenium could extend life. After feeding the colony sodium selenium at concentrations of 0.3 mg/liter and 0.6 mg/liter, the results showed that 0.6 mg/liter sodium selenite could enhance the antioxidant and immune activity of 6-d-old larvae and 1-d-old and 9-d-old worker bees (P < 0.05), increase the Se content of body tissues (P < 0.05) and RJ (P < 0.05), and improve the expression of related genes (P < 0.05). [ABSTRACT FROM AUTHOR]

Objective. Recent studies have identified chronic kidney disease (CKD) as an important risk factor for vasculopathies. While the link between CKD and cardiovascular events is well established, the link with cerebrovascular lesions (CVL) has been less well described.Methods. We studied the prevalence and prognostic importance of CKD in 1014 incident Chinese patients admitted with verified computerized tomography (CT) or magnetic resonance imaging (MRI) CVL (within the last 7 days). Laboratory data included the urinary microalbumin-to-creatinine ratio, routine urinalysis, fasting plasma glucose, serum creatinine, uric acid and other measures. Estimated glomerular filtration rate was calculated (using the modification of diet in renal disease formula) and CKD stages were classified according to kidney disease outcome quality initiative (K/DOQI) guidelines. Patients were followed for 30 days and any neurological sequelae were recorded.Results. A total of 1014 patients were enrolled (455 females, aged 68.56 ±12.17 years). Among these, 708 had ischemic stroke, 197 hemorrhagic stroke and 109 had transient cerebral ischemic attack. Microalbuminuria was detected in 11.2% of patients, while 24.8% had proteinuria. Of all patients, 6.90% had Stage 1, 14.69% Stage 2, 21.60% Stage 3, 2.56% Stage 4 and 1.97% had Stage 5, giving a total prevalence of CKD at 47.7%. In logistic regression, proteinuria (odds ratio = 1.69), hyperglycemia (odds ratio = 1.67) and anemia (odds ratio = 1.37) were independent predictors for risk of sequelae at 30 days for both ischemic and non-ischemic CVL.Conclusion. We report a high prevalence of CKD among Chinese patients with incident CVL. Proteinuria, hyperglycemia and anemia were prognostic factors in these patients. [ABSTRACT FROM AUTHOR]

Stereotaxis Niobe™ remote magnetic navigation system (MNS) (St Louise, USA), is a new technology that has applications in the field of catheter based ablation treatment of cardiac arrhythmias. Most if not all data on the feasibility, safety, and efficacy of the Stereotaxis Niobe™ MNS comes from select centres where highly skilled personnel have acquired considerable experience using this technology. Herein, we report a case where the Stereotaxis Niobe™ MNS was successfully used to perform remotely-controlled high density three-dimensional electroanatomical mapping and radiofrequency ablation of a focal atrial tachycardia originating from the anteroseptal region of the left atrium. [ABSTRACT FROM PUBLISHER]