Tetrahydrofolate and 5-methyltetrahydrofolate are folates with high antioxidant activity. Identification of the antioxidant pharmacophore

The presumed protective effect of folic acid on the pathogenesis of cardiovascular, hematological and neurological diseases and cancer has been associated with the antioxidant activity of folic acid. Peroxynitrite (PON) scavenging activity and inhibition of lipid peroxidation (LPO) of the physiological forms of folate and of structurally related compounds were tested. It was found that the fully reduced forms of folate, i.e. tetrahydrofolate (THF) and 5-methyltetrahydrofolate (5-MTHF), had the most prominent antioxidant activity. It appeared that their protection against LPO is less pronounced than their PON scavenging activity. The antioxidant activity of these forms of folic acid resides in the pterin core, the antioxidant pharmacophore is 4-hydroxy-2,5,6-triaminopyrimidine. It is suggested that an electron donating effect of the 5-amino group is of major importance for the antioxidant activity of 4-hydroxy-2,5,6-triaminopyrimidine. A similar electron donating effect is probably important for the antioxidant activity of THF and 5-MTHF.     

Kerogen-bound and free hopanoic acids in the messel oil shale kerogen

The distribution of the free and bound hopanoic acids in both unheated and heated (350 degrees C for 50 h) kerogens, isolated from the Messel oil shale, were analyzed by GC-MS. The bound acids were released by subjecting the kerogen to three different treatments, namely, thermochemolysis in the presence of tetramethylammonium hydroxide (TMAH), as well as basic and acidic hydrolyses. All of these methods gave a series of hopanoic acids ranging from C(30) to C(34), in which the biological 17beta, 21beta(H) configuration is prominent. Both 22R and 22S epimers are present for the C(30) acid, whereas the others are dominated by the sidechain 22R-configuration. Thermochemolysis in the presence of TMAH was the most efficient in releasing kerogen-bound hopanoids. Following pyrolysis, the acids are generated and released into the free fraction with apparent epimerization occurring at C-17, C-21, and C-22. The bound hopanoic acids may be both chemically bonded as well as possibly being physically encapsulated within the macromolecular fraction of sedimentary organic matter. They are therefore either generated by breaking the bonds which bind them to the kerogen or they are released as a result of the macromolecular cage being broken apart.     

Histochemical characterization of the lead intranuclear inclusion bodies

A battery of histological and histochemical techniques was applied on the lead intranuclear bodies that have resuted in the kidneys of adult Wistar male rats receiving lead acetate in their diet to determine their nature. The intranuclear inclusion bodies have stained strongly with xanthene, anthraquinone, and trisulfonated basophilic dyes and weakly with dyes containing both positive and negative radicals, and they have responded negatively to acidophilic cationic dyes. They have also reacted positively to proteins and lead stains, but weakly to lipid stains, and negatively to Feulgen and methyl green pyronin techniques. The intranuclear bodies proved to be lead lipoprotein complexes containing sulfyhydryl groups and are basic in nature with orthochromatic, eosinophilic, argyrophilic, osmophilic, fuchsinophilic, and sudanophilic characteristics.     

Micro-assembly of functionalized particulate monolayer on C18-derivatized SiO2 surfaces

This work describes a simple approach to immobilize functionalized colloidal microstructures onto a C(18)-coated SiO(2) substrate via specific or non-specific bio-mediated interactions. Biotinylated bovine serum albumin pre-adsorbed onto a C(18) surface was used to mediate the surface assembly of streptavidin-coated microbeads (2.8 microm), while a bare C(18) surface was used to immobilize anti-Listeria antibody-coated microbeads (2.8 microm) through hydrophobic interactions. For a C(18) surface pre-adsorbed with bovine serum albumin, hydrophobic polystyrene microbeads (0.8 microm) and positively charged dimethylamino microbeads (0.8 microm) were allowed to self-assemble onto the surface. A monolayer with high surface coverage was observed for both polystyrene and dimethylamino microbeads. The adsorption characteristics of Escherichia coli and Listeria monocytogenes on these microbead-based surfaces were studied using fluorescence microscopy. Both streptavidin microbeads pre-adsorbed with biotinylated anti-Listeria antibody and anti-Listeria antibody-coated microbeads showed specific capture of L. monocytogenes, while polystyrene and dimethylamino microbeads captured both E. coli and L. monocytogenes non-specifically. The preparation of microbead-based surfaces for the construction of microfluidic devices for separation, detection, or analysis of specific biological species is discussed.     

Dual regulation of the cardiac L-type calcium channel in L6 cells by protein kinase C

The role of protein kinase C (PKC) in the regulation of cardiac L-type Ca²⁺ channel activity (LCC) was investigated in L6 rat neonatal myoblasts. Depolarization of fura-2 loaded cells with 140 mM KCl activated a Ba²⁺ influx pathway that was blocked by nifedipine and stimulated by (−) Bay K 8644. At least two splice variants of the α_1C subunit of the cardiac LCC were identified by PCR; the α_1S subunit of the skeletal muscle LCC was not detected. Peptides that specifically inhibit translocation of the novel, Ca²⁺-independent δ and PKC isozymes reduced Ba²⁺ influx by 27% and 19%, respectively, whereas a corresponding peptide directed against translocation of classical PKC α had no effect. Ingenol 3,20-dibenzoate, an agent reported to selectively activate novel PKCs, increased Ba²⁺ uptake by 31% while ethanol, a PKC agonist, enhanced uptake by 38%. In contrast, selective activation of classical PKCs with thymeleatoxin or an agonist peptide reduced Ba²⁺ influx by 23–33%. Ba²⁺ influx was reduced by 30–40% when cells were treated with either a PKC inhibitor (Gö 6983, bisindolylmaleimide) or the PKC activator phorbol-12-myristate-13-acetate. We propose that novel, Ca²⁺-insensitive PKC(s) enhance cardiac Ca²⁺ channel activity in L6 cells under basal conditions while activation of the classical, Ca²⁺-sensitive PKC(s) inhibits channel activity. These findings provide the first evidence that different PKC isozymes exert class-specific opposing effects on cardiac L-type Ca²⁺ channel activity in L6 myoblasts.     

Perspective Texture Synthesis Based on Improved Energy Optimization

Perspective texture synthesis has great significance in many fields like video editing, scene capturing etc., due to its ability to read and control global feature information. In this paper, we present a novel example-based, specifically energy optimization-based algorithm, to synthesize perspective textures. Energy optimization technique is a pixel-based approach, so it’s time-consuming. We improve it from two aspects with the purpose of achieving faster synthesis and high quality. Firstly, we change this pixel-based technique by replacing the pixel computation with a little patch. Secondly, we present a novel technique to accelerate searching nearest neighborhoods in energy optimization. Using k- means clustering technique to build a search tree to accelerate the search. Hence, we make use of principal component analysis (PCA) technique to reduce dimensions of input vectors. The high quality results prove that our approach is feasible. Besides, our proposed algorithm needs shorter time relative to other similar methods.     

Age- and Gender-Based Studies of Trace Metal Levels and Various Enzymes Associated with Myocardial Infarction

The present investigation deals with the determination of various serum enzymes known to be elevated during myocardial infarction (MI) and estimation of selected metals like Cu, Cr, Co, Fe, Pb, and Mg by flame atomic absorption spectrophotometry. The data obtained thereby were processed for the determination of correlation coefficient matrix among the cardiac enzymes and the serum metals. The study evidenced the accumulation of Pb during MI and reduction in the level of Fe. A significant negative correlation was observed between Cu and creatine kinase-MB. The data were also segregated into various groups to study the influence of age and gender on the levels of selected parameters. In both the genders, the age of the patients was found to be correlated significantly with various cardiac enzymes. In case of male patients, the most significant correlation was observed between age and blood sugar at random. The other significant correlations among the male patients included Cr–CPK, Cr–creatine kinase-MB, Fe–age, and others. In female patients, the pairs of studied parameters that exhibited significant correlations included age–lactic dehydrogenase, creatine phosphokinase isoenzyme–aspartate aminotransferase, lactic dehydrogenase–creatine phosphokinase isoenzymes, Pb-Fe, and Cu-Co in addition to others.     

Soil-transmitted helminths in relation to hemoglobin status among school children of the Kashmir Valley

Soil-transmitted helminths (STHs) remain a major threat to the health of children throughout the world, mostly in developing nations. The aim of the present study was to determine any relationship between STHs and hemoglobin status in school children of Kashmir Valley (India). Stool and blood samples were collected from 382 male and female school children in the age group of 5-15 yr from all 6 school districts of the Kashmir Valley. Finger-prick blood samples were used to collect the hemoglobin, which was then measured on-site by Sahli's acid hematin method; stool samples were processed using both simple smear and zinc sulphate concentration methods. Of the 382 children surveyed, 299 (78.27%) were infected with Ascaris lumbricoides, Trichuris trichiura, or both. Children infected by STHs were found to have lower mean values of hemoglobin than uninfected children. The present study reveals that STHs are abundant among school children of Kashmir Valley, creating a negative effect on the hemoglobin values and indicating the necessity of implementing control measures.     

Low nitrogen stress regulates chlorophyll fluorescence in coordination with photosynthesis and Rubisco efficiency of rice

Nitrogen (N) is the basis of plant growth and development and, is considered as one of the priming agents to elevate a range of stresses. Plants use solar radiations through photosynthesis, which amasses the assimilatory components of crop yield to meet the global demand for food. Nitrogen is the main regulator in the allocation of photosynthetic apparatus which changes of the photosynthesis (P_n) and quantum yield (F_v/F_m) of the plant. In the present study, dynamics of the photosynthetic establishment, N-dependent relation with chlorophyll fluorescence attributes and Rubisco efficacy was evaluated in low-N tolerant (cv. CR Dhan 311) and low-N sensitive (cv. Rasi) rice cultivars under low-N and optimum-N conditions. There was a decrease in the stored leaf N under low-N condition, resulting in the decreased P_n and F_v/F_m efficiency of the plants through depletion in the activity and content of Rubisco. The P_n and F_v/F_m followed the parallel trend of leaf N content during low-N condition along with depletion of intercellular CO₂ concentration and overall conductance under low-N condition. Photosynthetic saturation curve cleared abrupt decrease of effective quantum yield in the low-N sensitive rice cultivar than the low-N tolerant rice. Also, the rapid light curve highlighted the unacclimated regulation of photochemical and non-photochemical quenching in the low-N condition. The low-N sensitive rice cultivar triumphed non-photochemical quenching, whereas the low-N tolerant rice cultivar rose gradually during the light curve. Our study suggested that the quantum yield is the key limitation for photosynthesis in low-N condition. Regulation of Rubisco, photochemical and non-photochemical quenching may help plants to grow under low-N level.