The influence of seed priming on germination, seedling vigor, ion homeostasis, and starch metabolism in coarse rice was studied. Priming treatments included pregermination (a traditional soaking method being used for rice nursery preparation), hydropriming for 48 h, osmohardening with KCl or CaCl2 (ψs –1.25 MPa solution) for 24 h, ascorbate priming (10 mg·L–1) for 48 h, and hardening for 24 h. Compared with controls, all priming treatments (except pregermination) reduced the time to start germination, improved the rate of germination and synchronization, and the length of shoot and root, seedling fresh and dry mass, number of secondary roots, the concentration of reducing sugars, and α-amylase activity, although the extent of these changes was different in seeds subjected to different treatments. These seed treatments resulted in higher germination that might be due to overcoming dormancy. Osmohardening with KCl was more effective than CaCl2 for these parameters. Nitrogen concentration remained unaffected in seedlings; however, Ca2+ concentrations in both seeds and seedlings were greater in seeds osmohardenerd with CaCl2 than with all other treatments, including the control. Seed priming enhanced K+ concentration in both seeds and seedlings, leading to improved α-amylase activity. There were positive correlations between seed K+ concentration and amylase activity, and the concentration of reducing sugars with amylase activity, seedling dry mass, or number of secondary roots. Osmohardening with KCl performed better than all other treatments including control. Priming improved the K+ balance that activates α-amylase, a basis for seed invigoration.

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Gallic acid (GA), a plant-derived ubiquitous secondary polyphenol metabolite, can be a useful dietary supplement. This in vitro study’s primary purpose was to assess the anti-aging properties of GA using rat embryonic fibroblast (REF) cells, antidiabetic effects via pancreatic islet cells, and finally, elucidating the molecular mechanisms of this natural compound. REF and islet cells were isolated from fetuses and pancreas of rats, respectively. Then, several senescence-associated molecular and biochemical parameters, along with antidiabetic markers, were investigated. GA caused a significant decrease in the β-galactosidase activity and reduced inflammatory cytokines and oxidative stress markers in REF cells. GA reduced the G0/G1 phase in senescent REF cells that led cells to G2/M. Besides, GA improved the function of the β cells. Flow cytometry and spectrophotometric analysis showed that it reduces apoptosis via inhibiting caspase-9 activity. Taken together, based on the present findings, this polyphenol metabolite at low doses regulates different pathways of senescence and diabetes through its antioxidative stress potential and modulation of mitochondrial complexes activities.

Neutral endopeptidase (NEP), which degrades substance P (SP), may regulate neutrophil activation during Mg-deficiency (MgD). Male Sprague-Dawley rats (180g) were fed MgD (~50 mg Mg/kg) or Mg-sufficient (MgS, 608 mg Mg/kg) diets for 7 days ± NEP inhibitor phosphoramidon (PR, 5 mg/kg/day, s. c.). MgD alone induced a 9-fold (vs. MgS, p <0.01) elevation in plasma SP; MgD+PR enhanced it further to 18-fold (p <0.001). Neutrophils from MgD+PR rats displayed a 3.9-fold higher (p <0.01) basal ·O2- generation, but those from MgD or PR alone were not activated. Plasma PGE2-metabolite levels rose 2.67- (p <0.01) and 1.56- (p <0.05) fold, respectively, in MgD+PR and MgD groups; the corresponding red blood cell glutathione levels were decreased 21 % (p <0.025) and 7 % (NS). MgD+PR significantly reduced neutrophil NEP activity by 48 % (p <0.02); PR or MgD alone only reduced this activity 26 % and 15 %, respectively. We conclude that NEP inhibition potentiates SP-mediated neutrophil ·O2- production and may promote other inflammatory activities during MgD.

Two-dimensional assemblies of Au–Pt bimetallic nanoparticles are generated in situ on polyethyleneimmine (PEI) silane functionalized silicon and indium tin oxide (ITO) coated glass surfaces. Atomic force microscopy (AFM), UV–Visible spectroscopy, and electrochemical measurements reveal the formation of core–shell structure with Au as core and Pt as shell. The core–shell structure is further supported by comparing with the corresponding data of Au nanoparticle assemblies. Static contact angle measurements with water show an increase in hydrophilic character due to bimetallic nanoparticle generation on different surfaces. It is further observed that these Au–Pt core–shell bimetallic nanoparticle assemblies are catalytically active towards methanol electro-oxidation, which is the key reaction for direct methanol fuel cells (DMFCs).

Extensive research has focused on the neurotransmitter dopamine because of its importance in the mechanism of action of drugs of abuse (e.g. cocaine and amphetamine), the role it plays in psychiatric illnesses (e.g. schizophrenia and Attention Deficit Hyperactivity Disorder), and its involvement in degenerative disorders like Parkinson's and Huntington's disease. Under normal physiological conditions, dopamine is known to regulate locomotor activity, cognition, learning, emotional affect, and neuroendocrine hormone secretion. One of the largest densities of dopamine neurons is within the striatum, which can be divided in two distinct neuroanatomical regions known as the nucleus accumbens and the caudate-putamen. The objective is to illustrate a general protocol for slice fast-scan cyclic voltammetry (FSCV) within the mouse striatum. FSCV is a well-defined electrochemical technique providing the opportunity to measure dopamine release and uptake in real time in discrete brain regions. Carbon fiber microelectrodes (diameter of~7 μm) are used in FSCV to detect dopamine oxidation. The analytical advantage of using FSCV to detect dopamine is its enhanced temporal resolution of 100 milliseconds and spatial resolution of less than ten microns, providing complementary information to in vivo microdialysis. Video LinkThe • There are numerous carbon fiber microelectrodes fabrication methods since most are made in-house. Typically what dictates the electrode fabrication details is the electrochemical technique that is applied to the electrode (e.g. amperometry vs. FSCV). For FSCV, microelectrodes can be made in-house using the following three-step procedure. For a more complete description of carbon fiber electrode fabrication, see a recent JOVE article 1 . However, note that the electrodes described below are cylindrical carbon fiber microelectrodes, which require fewer steps to fabricate versus the amperometric carbon fiber microelectrodes from the above-mentioned protocol. This simplified protocol does not require boiling the carbon fiber in acetone, fire-polishing the glass capillaries, or using epoxy to seal the glass-fiber junction.• Using vacuum suction aspirate a carbon fiber (diameter 7 μm; Goodfellow Oakdale, PA) into a borosilicate glass capillary with microfilament (length 10 cm, o.d. 1.2 mm, i.d. 0.68 mm; A-M systems, Carlsborg, WA).• Place the threaded capillary into the electrode puller (Narishige, Tokyo, Japan) where the capillary is pulled in half. Output settings for the electrode puller do vary from lab to lab. For reference, our output settings for the puller are 90.7 main magnet, 23.2 sub-magnet, and 53.4 for the heater. The output settings should be empirically refined to generate a glass taper that is approximately 4.4 mm in length, with a tight seal around the carbon fiber.• Under a microscope (Olympus, Tokyo, Japan), trim the carbon fiber (using a scalpel blade) extending from the glass tip allowing approximately 50-200 μm of the carbon fiber to protrude from the tightly sealed interface.• S...