Snap-8 mercury corrosion and materials research, volume iii topical report, jun. 1960 - dec. 1962

SNAP-8 materials research - mercury corrosion capsule tests of ferritic alloys for mass transfer, stress corrosion, mode of attack, and mechanical propertie

Role of morphine preconditioning and nitric oxide following brain ischemia reperfusion injury in mice

Objective(s): Morphine dependence (MD) potently protects heart against ischemia reperfusion (IR) injury through specific signaling mechanisms, which are different from the pathways involved in acute morphine treatment or classical preconditioning. Since opioid receptor density changes post cerebral ischemia strongly correlated with brain histological damage, in the present study, we tried to elucidate the possible role of opioid receptors in IR injury among morphine-dependent mice. Materials and Methods: Accordingly, incremental doses (10 mg/kg/day to 30 mg/kg/day) of morphine sulphate were subcutaneously administered for 5 days before global brain ischemia induction through bilateral common carotid artery occlusion. Animals were received naloxone (5 mg/kg) or L-NAME (20 mg/kg) 30 min after the last morphine dose. Twenty four hr after the ischemia induction, Retention trial of passive avoidance test and western blot analysis were done. histological analysis (TUNEL and NISSL staining) performed 72 hr after ischemia. Results: MD improved post ischemia memory performance (P<0.01) and neuronal survival (P<0.001) and decreased apoptosis (P<0.05) in region I of hippocampus (CA1 region) in mouse. Treatment with naloxone or L-NAME abolished all MD aforementioned effects. Conclusion: Results of the present study suggested that opioid receptors activation in the early hr post ischemia is crucial for MD-induced hippocampus tolerance against IR injury. Opioid receptor-dependent balance of NO production was another key factor in MD-induced protection. Further studies are required to determine the effect of MD on opioid receptor changes after ischemia and its correlation with MD-induced protection. © 2015, Mashhad University of Medical Sciences. All rights reserved

Insights into role of microRNAs in cardiac development, cardiac diseases, and developing novel therapies

MicroRNAs (miRNAs) are a subfamily of small noncoding RNAs that play a variety of roles in regulating gene expression in nearly all organisms. They affect different biological pathways by posttranscriptionally regulating mRNAs. Aside from miRNAs' role in maintaining cellular homeostasis, their perturbation is related to several pathologic states and diseases. Cardiovascular disorders are considered some of the most mortal multifactorial diseases that are caused by the deregulation of network of genes and effects of environmental factors. In this review, we discuss the role of miRNAs in cardiac homeostasis and malfunctions. We reviewed published research on association and role of miRNAs in cardiac development and diseases and investigated the possible links between regulatory miRNAs and different cardiac disorders. Research shows that manipulating miRNAs expression affects the integrity and functionality of the cardiovascular system. Moreover, deregulation of miRNAs, is observed in many cardiac diseases. These findings intensify the pivotal role of miRNAs in the development and specific pathological disorders of the cardiovascular system. In this review, we summarized the latest findings on the involvement of miRNAs in cardiac development, and continued by their role in congenital heart diseases and rheumatic heart disease, which are some of the leading causes of infant death and cardiovascular morbidity and mortality. Considering the significance of miRNAs in cardiac homeostasis and malfunctions, they are considered as promising therapeutic targets in cardiovascular diseases. © 2020 Mashhad University of Medical Sciences. All rights reserved

Prey preference of Eupeodes corollae (Dip.: Syrphidae) on different nymphal instars of Brevicoryne brassicae (Hem.: Aphididae)

The prey stage preferences of the second and third instar larvae of syrphid fly species Eupeodes corollae (Fabricius) on different nymphal instars of Brevicoryne brassicae (L.) were studied in no-choice and choice conditions (25 ± 2°C, 65 ± 5% R.H. and 16L: 8D photoperiod). In no-choice test, the second and third instar larvae of E. corollae were separately supplied with a total of 40 nymphal instars of B. brassicae. In choice test, 10 nymphs from all nymphal stages of B. brassicae were simultaneously offered to the second and third instar larvae of E. corollae. In no-choice test, the highest larval feeding of the second (25.00 ± 2.61) and third (38.2 ± 0.58) instar larvae of E. corollae were observed on the first and second nymphal instars of B. brassicae, respectively. However, there were not significant differences in their feeding behavior on the first to third nymphal instars of B. brassicae. In choice test, the highest feeding rate of second instar larvae was 5.00 ±0.84 aphids on third instar nymphs of B. brassicae. No significant differences were observed in feeding rates of the predatorâs third instar larvae. Switching behavior was not observed for the third instar larvae of E. corollae, while different second: third instar ratio found to be 10:50, 20:40, 30:30, 40:20 and 50:10

Sentiment-Apt investors and UK sector returns

This paper examines the relationship between sentiment-apt investors and UK stock returns at industry level over the period January 1988 to December 2017. Using two new sentiment proxies (laggards to leaders and growth opportunity index) for 10 discrete sector groupings, we provide novel evidence on how returns in the UK stock market react to the activities of sentiment-disposed investors. First, using threshold nonlinear regression, we document a significant relationship between the laggards to leaders sentiment proxy and sectoral returns. Our findings reveal that aggregate returns in the sector are affected by activities of investors who embark on profit-taking when there is an increase in the proportion of lagging to leading stocks beyond the threshold value. Secondly, when using the growth opportunity sentiment proxy, we report that the increase in growth above the growth threshold value has a significant impact on sector returns. This study further confirms significant impact of non-threshold variables on sector groupings. Our findings are robust, having been subjected to a range of robustness checks

Small Molecules with Big Impacts on Cardiovascular Diseases

Cardiovascular diseases (CVDs) are the leading cause of morbidity and mortality worldwide. Although in recent years there has been a significant progress in the diagnosis, treatment, and prognosis of CVD, but due to their complex pathobiology, developing novel biomarkers and therapeutic interventions are still in need. MicroRNAs (miRNAs) are a fraction of non-coding RNAs that act as micro-regulators of gene expression. Mounting evidences over the last decade confirmed that microRNAs were deregulated in several CVDs and manipulating their expression could affect homeostasis, differentiation, and function of cardiovascular system. Here, we review the current knowledge concerning the roles of miRNAs in cardiovascular diseases with more details on cardiac remodeling, arrhythmias, and atherosclerosis. In addition, we discuss the latest findings on the potential therapeutic applications of miRNAs in cardiovascular diseases. © 2020, Springer Science+Business Media, LLC, part of Springer Nature