High-Temperature unfolding of a trp-Cage mini-protein: a molecular dynamics simulation study

Background  

Trp cage is a recently-constructed fast-folding miniprotein. It consists of a short helix, a 3,10 helix and a C-terminal poly-proline that packs against a Trp in the alpha helix. It is known to fold within 4 ns.     

Low-Cost Plasmonic Carbon Spacer for Surface Plasmon-Coupled Emission Enhancements and Ethanol Detection: a Smartphone Approach

Surface plasmon-coupled emission (SPCE) has led to significant advancements in analytical techniques on account of its unique characteristics that include highly polarized photon-sorting ability. In this study, we report the use of a low-cost activated carbon as a plasmonic spacer in the SPCE substrate for achieving 30-fold enhancement in fluorescence emission. We extend the use of this spacer in the presence of Rhodamine B Base, a lactone dye as the sensing material for smartphone-based ethanol detection on the SPCE platform. Ethanol detection from 1 to 6% concentration highlights the potential use of this technique in monitoring fermentation processes.     

An Improved Method for Rapid Fixation and Embedding of Pteridophyte Plant Materials

A rapid method for fixation and embedding of plant materials, especially pterido-phytes, is suggested. Addition of tannic acid following osmication improved the visualization of membranes. Staining en bloc with uranyl acetate between osmication and tannic acid is suggested for tissues infected with fungi and bacteria.     

Trace Element Determination and Cardioprotection of <Emphasis Type="Italic">Terminalia pallida</Emphasis> Fruit Ethanolic Extract in Isoproterenol Induced Myocardial Infarcted Rats by ICP-MS

The trace elements and minerals in Terminalia pallida fruit ethanolic extract (TpFE) were determined by the instrument inductively coupled plasma-mass spectrometry (ICP-MS), and the cardioprotection of TpFE against isoproterenol (ISO)-administered rats was studied. Rats were pretreated with TpFE (100, 300, and 500 mg/kg bw) for 30 days, with concurrent administration of ISO (85 mg/kg bw) for two consecutive days. The levels of trace elements and minerals in TpFE were below the permitted limits of World Health Organization standards. ISO administration significantly increased the heart weight and cardiac marker enzymes in serum, xanthine oxidase, sodium, and calcium in the heart, whereas significantly decreased body weight, reduced glutathione, glutathione-S-transferase, superoxide dismutase, and potassium in the heart. Oral pretreatment of TpFE significantly prevented the ISO-induced alterations. This is the first report that revealed the determination of trace elements and mineral nutrients of TpFE by ICP-MS which plays a principal role in the herbal drug discovery for the treatment of cardiovascular diseases.     

Role of Trace Elements,Oxidative Stress and Immune System: a Triad in Premature Ovarian Failure

Cadmium is an environmental pollutant closely linked with cardiovascular diseases that seems to involve endothelium dysfunction and reduced nitric oxide (NO) bioavailability. Knowing that NO causes dilatation through the activation of potassium channels and Na⁺/K⁺-ATPase, we aimed to determine whether acute cadmium administration (10 μM) alters the participation of K⁺ channels, voltage-activated calcium channel, and Na⁺/K⁺-ATPase activity in vascular function of isolated aortic rings of rats. Cadmium did not modify the acetylcholine-induced relaxation. After L-NAME addition, the relaxation induced by acetylcholine was abolished in presence or absence of cadmium, suggesting that acutely, this metal did not change NO release. However, tetraethylammonium (a nonselective K⁺ channels blocker) reduced acetylcholine-induced relaxation but this effect was lower in the preparations with cadmium, suggesting a decrease of K⁺ channels function in acetylcholine response after cadmium incubation. Apamin (a selective blocker of small Ca²⁺-activated K⁺ channels—SK_Ca), iberiotoxin (a selective blocker of large-conductance Ca²⁺-activated K⁺ channels—BK_Ca), and verapamil (a blocker of calcium channel) reduced the endothelium-dependent relaxation only in the absence of cadmium. Finally, cadmium decreases Na⁺/K⁺-ATPase activity. Our results provide evidence that the cadmium acute incubation unaffected the calcium-activated potassium channels (SK_Ca and BK_Ca) and voltage-calcium channels on the acetylcholine vasodilatation. In addition, acute cadmium incubation seems to reduce the Na⁺/K⁺-ATPase activity.     

In vitro and in silico analyses of Vicia faba L. on Peroxisome proliferator–activated receptor gamma

The agonists of peroxisome proliferator–activated receptor gamma (PPARγ) from natural victual products were used as antidiabetic agents. Faba bean (Vicia faba L.) is a consequential legume that was known to possess potential antidiabetic activity, whose mechanism of action was unknown. The current study was focused to ascertain gene expression of the nuclear receptor PPARγ by Faba bean pod extract in rat cell lines (RINm5F).The real‐time polymerase chain reaction analysis demonstrated that Faba bean pod extract in concentrations of 160 µg/mL have shown 4.97‐fold stimulation compared with control. The cells treated with 320 µg/mL has shown 5.89‐fold upregulation, respectively. Furthermore, in silico docking analysis was carried out against PPARγ, using the bioactive compounds identified from Faba bean pod extracts, which were known reported compounds from the literature. The results suggest that gene expression of PPARγ was inhibited by the constituents in Faba bean. In silico analysis prognosticates, butein has a high binding energy (?8.6 kcal/mol) with an atomic contact energy of ?214.10, followed by Apigenin and Quercetin against PPARγ. Similarly, the percentage of interaction was high for butein, followed by Apigenin and Quercetin than other compounds comparatively. Hence, the results conclude inhibition of PPARγ by the bioactive compounds from Faba bean, which may provide insights into developing future therapeutic molecules for diabetes mellitus.     

Plant-mediated competition facilitates a phoretic association between a gall mite and a psyllid vector

Phoretic associations between mites and insects commonly occur in patchy and ephemeral habitats. As plants provide stable habitats for herbivores, herbivorous mites are rarely dependent on other animals for phoretic dispersal. However, a phoretic gall mite, Aceria pallida, which is found on plants, seasonally attaches to a herbivorous insect, Bactericera gobica, for overwintering survival. After detachment, the gall mite shares a habitat with its vector and is likely to compete with this vector for plant resources. However, excessive competition works against the sustainability of the seasonal phoretic association. How the gall mite, as an obligate phoretic mite, balances this relationship with its vector during the growing season to achieve phoresy is unknown. Here, the plant-mediated interspecific interaction between the gall mite and the psyllid after detachment was studied in the laboratory and field. The laboratory results showed that infestation by the gall mite had detrimental effects on the survival and development of psyllid nymphs. Meanwhile, the mite population and the gall size were also adversely affected. The results from the field showed that the mean densities of the mite galls and psyllids were lower in the mixed-species infestation treatment than in the single-species infestation treatment across the investigation period. However, the interspecific interaction between the gall mite and the psyllid decreased rather than accelerated leaf abscission caused by the psyllid, which promoted the persistence of the psyllid population and then indirectly contributed to phoretic association. Our results suggest that the plant-mediated competition between the phoretic gall mite and its vector after detachment facilitates the maintenance of the phoretic association.     

Influence of temperature and size on the respiration of a tropical intertidal gastropod,Morula granulata (Duclos), in air and water

Summary The effect of temperature on the size related metabolism of a tropical intertidal gastropod,Morula granulata (Duclos), was studied both in air and water. An increase was observed in the aerial and aquatic respiration with increasing size at all temperatures studied. Significant differences (P<0.05) were found between the regression values (b) and also the intercept values (a) of aerial and aquatic respiration at different temperatures. The aerial regression values at any given temperature were significantly higher (P<0.05) than the aquatic values. Aerial and aquatic respiration ofM. granulata at different temperatures are compared and discussed in relation to the habitat of the animal.