Regulatory thiol oxidation in chloroplast metabolism, oxidative stress response and environmental signaling in plants.

The antagonism between thiol oxidation and reduction enables efficient control of protein function and is used as central mechanism in cellular regulation. The best-studied mechanism is the dithiol-disulfide transition in the Calvin Benson Cycle in photosynthesis, including mixed disulfide formation by glutathionylation. The adjustment of the proper thiol redox state is a fundamental property of all cellular compartments.

On the Chameleonic Behaviour of Cholesterol through a Fractal/Multifractal Model.

An increasing number of studies are beginning to show that both low-density lipoprotein and high-density lipoprotein cholesterol can constitute risk factors for myocardial infarction. Such a behaviour has been called by experts in the field the "chameleonic effect" of cholesterol. In the present paper, a fractal/multifractal model for low-density lipoprotein and high-density lipoprotein cholesterol dynamics is proposed.

3D Chitin Scaffolds from the Marine Demosponge as a Support for Laccase Immobilization and Its Use in the Removal of Pharmaceuticals.

For the first time, 3D chitin scaffolds from the marine demosponge were used for adsorption and immobilization of laccase from . The resulting chitin-enzyme biocatalytic systems were applied in the removal of tetracycline. Effective enzyme immobilization was confirmed by scanning electron microscopy.

New Developments in Medical Applications of Hybrid Hydrogels Containing Natural Polymers.

New trends in biomedical applications of the hybrid polymeric hydrogels, obtained by combining natural polymers with synthetic ones, have been reviewed. Homopolysaccharides, heteropolysaccharides, as well as polypeptides, proteins and nucleic acids, are presented from the point of view of their ability to form hydrogels with synthetic polymers, the preparation procedures for polymeric organic hybrid hydrogels, general physico-chemical properties and main biomedical applications (i.e.

Redox regulation by peroxiredoxins is linked to their thioredoxin-dependent oxidase function.

The chloroplast contains three types of peroxiredoxins (PRXs). Recently, 2-CysPRX was associated with thioredoxin (TRX) oxidation-dependent redox regulation. Here, this analysis was expanded to include PRXQ and PRXIIE.

Secondary metabolites from Penicillium sp. 8PKH isolated from deteriorated rice straws.

In the search for bioactive secondary metabolites from terrestrial fungi, four compounds, namely, 3-methyl-3H-quinazolin-4-one (1), aurantiomide C (2), 3-O-methylviridicatin (3), and dehydrocyclopeptine (4), were isolated from Penicillium sp. 8PKH, fungal strain, isolated from deteriorated rice straws. The structures of the isolated compounds were identified by extensive NMR and mass analyses and comparison with literature data.

Physical Hydrogels of Oxidized Polysaccharides and Poly(Vinyl Alcohol) for Wound Dressing Applications.

Two natural polymers, i.e., cellulose and water soluble pullulan, have been selectively oxidized employing the TEMPO-mediated protocol, to allow the introduction of C-OOH groups.

Chitosan grafted-poly(ethylene glycol) methacrylate nanoparticles as carrier for controlled release of bevacizumab.

The aim of the present study is to obtain, for the first time, polymeric nanocarriers based on the chitosan grafted-poly(ethylene glycol) methacrylate derivative. The strategy involves the use of chitosan grafted-poly(ethylene glycol) methacrylate with high solubility in water, obtained via Michael addition, in order to prepare potentially non-toxic micro/nanoparticles (MNPs). By modifying chitosan, its solubility in aqueous media was improved.

In vitro study of the anticancer activity of various doxorubicin-containing dispersions.

The aim of this research was to study the impact of various doxorubicin (Dox)-containing nanofluids, e.g. singlewalled carbon nanotube (SWCNT)+Dox, graphene oxide (GO)+Dox and DextranPNIPAM (copolymer)+Dox mixtures on HeLa cells (human transformed cervix epithelial cells, as a model for cancer cells) depending on their concentration.

Tether-Directed Regioselective Synthesis of an Equatorial Bisadduct of Azafullerene Using Cyclo-[2]-octylmalonate.

Bisazafullerene (C N) has been functionalized under aerobic conditions with cyclo-[2]-octylmalonate through a Mannich-type reaction, furnishing the corresponding monoadduct. A regioselective tether-directed Bingel cyclopropanation reaction was then carried out on the azafullerene core to yield a single bisadduct. Spectroscopic analysis of the formed bisadduct showed it to have a C symmetrical structure, making it inherently chiral.

Ameliorative effects of Matricaria chamomilla L. hydroalcoholic extract on scopolamine-induced memory impairment in rats: A behavioral and molecular study.

Background: Matricaria chamomilla L. is a medicinal herb traditionally used as the anti-inflammatory, antimicrobial, antiviral, anxiolytic and antidepressant agent. Nevertheless, supporting evidence demonstrated its memory enhancing activity and antioxidant properties.

Clinical Influence of Micromorphological Structure of Dental Implant Bone Drills.

Background: Considerations about heat generation, wear, and corrosion due to some macrostructural bur components (e.g., cutting lips, rake angle, flute, and helix angle) have been widely reported.

The Fundamental Role of Reactive Oxygen Species in Plant Stress Response.

Chemical, physical, and biotic factors continuously vary in the natural environment. Such parameters are considered as stressors if the magnitude of their change exceeds the current acclimation norm of the plant. Activation of genetic programs allows for conditional expansion of the acclimation norm and depends on specific sensing mechanisms, intracellular communication, and regulation.

Spectral dependence of irreversible light-induced fluorescence quenching: Chlorophyll forms with maximal emission at 700-702 and 705-710nm as spectroscopic markers of conformational changes in the core complex.

The spectral dependence of the irreversible non-photochemical fluorescence quenching associated with photoinhibition in vitro has been comparatively investigated in thylakoid membranes, PSII enriched particles and PSII core complexes isolated from spinach. The analysis of the fluorescence emission spectra of dark-adapted and quenched samples as a function of the detection temperature in the 280-80K interval, indicates that Chlorophyll spectral forms having maximal emission in the 700-702nm and 705-710nm ranges gain relative intensity in concomitance with the establishment of irreversible light-induced quenching, acting thereby as spectroscopic markers. The relative enhancement of the 700-702nm and 705-710nm forms emission could be due either to an increase of their stoichiometric abundance or to their intrinsically low fluorescence quantum yields.

Cognitive-enhancing and antioxidant activities of the aqueous extract from Markhamia tomentosa (Benth.) K. Schum. stem bark in a rat model of scopolamine.

Background: Plants of the genus Markhamia have been traditionally used by different tribes in various parts of West African countries, including Cameroun. Markhamia tomentosa (Benth.) K.

New mechanisms of vesicles migration.

In multicellular organisms, both health and disease are defined by means of communication patterns involving the component cells. Despite the intricate networks of soluble mediators, cells are also programed to exchange complex messages pre-assembled as multimolecular cargo of membranous structures known as extracellular vesicles (EVs). Several biogenetic pathways produce EVs with different properties able to orchestrate neighboring cell reactions or to establish an environment ripe for spreading tumor cells.

A new fluorinated urethane dimethacrylate with carboxylic groups for use in dental adhesive compositions.

A urethane macromer containing hexafluoroisopropylidene, poly(ethylene oxide) and carboxylic moieties (UF-DMA) was synthesized and used in proportions varying between 15 and 35 wt.% (F1-F3) in dental adhesive formulations besides BisGMA, triethylene glycol dimethacrylate and 2-hydroxyethyl methacrylate. The FTIR and (1)H ((13)C) NMR spectra confirmed the chemical structure of the UF-DMA.

Synthesis of Enantiopure T-Symmetrical [6:0]-Hexakis Adducts of C60 Equipped with 1,2-Glycol Substituted cyclo-Monomalonate Addends.

The synthesis of T-symmetrical [6:0]-hexakis adducts of C60 bearing enantiopure cyclo-monomalonate addends equipped with 1,2-glycol groups masked as isopropylidene acetals is presented. The deprotection of the acetals afforded functional fullerene building blocks bearing six 1,2-glycol moieties in an octahedral geometry as connection sites with appropriate linear organic spacers targeting 3D chiral extended networks with cubic building units. Evaluation of the experimental results revealed the advantageous synthetic accessibility to hexakis adduct (-)-9 which carries six homochiral C12 cyclo-monomalonate addends.

Neurobiology of rodent self-grooming and its value for translational neuroscience.

Self-grooming is a complex innate behaviour with an evolutionarily conserved sequencing pattern and is one of the most frequently performed behavioural activities in rodents. In this Review, we discuss the neurobiology of rodent self-grooming, and we highlight studies of rodent models of neuropsychiatric disorders--including models of autism spectrum disorder and obsessive compulsive disorder--that have assessed self-grooming phenotypes. We suggest that rodent self-grooming may be a useful measure of repetitive behaviour in such models, and therefore of value to translational psychiatry.

Effects of the Methanolic Extract of Vitellaria paradoxa Stem Bark Against Scopolamine-Induced Cognitive Dysfunction and Oxidative Stress in the Rat Hippocampus.

Vitellaria paradoxa C.F. Gaertn (Sapotaceae) is a perennial three which naturally grows in the northern part of Cameroon.

Formulation and evaluation of cefuroxim loaded submicron particles for ophthalmic delivery.

Chitosan gelatin particles could be the ideal candidate for intraocular drug delivery due to their desirable properties. Double crosslinking in double emulsion has been used as an original and reliable method for particles preparation and their morphology has been optimized considering the main synthesis parameters such as polymers ratio, crosslinker amount, stirring speed, tensioactive amount and ionic crosslinking time, respectively. The particles have been analyzed for their physical-chemical properties (swelling degree, drug loading and release capacity, surface characteristics, etc.

Anxiolytic and antidepressant profile of the methanolic extract of Piper nigrum fruits in beta-amyloid (1-42) rat model of Alzheimer's disease.

Background: Piper nigrum L. (Piperaceae) is employed in traditional medicine of many countries as analgesic, antiinflammatory, anticonvulsant, antioxidant, antidepressant and cognitive-enhancing agent. This study was undertaken in order to evaluate the possible anxiolytic, antidepressant and antioxidant properties of the methanolic extract of Piper nigrum fruits in beta-amyloid (1-42) rat model of Alzheimer's disease.

Characterization of the chaos-hyperchaos transition based on return times.

We discuss the problem of the detection of hyperchaotic oscillations in coupled nonlinear systems when the available information about this complex dynamical regime is very limited. We demonstrate the ability of diagnosing the chaos-hyperchaos transition from return times into a Poincaré section and show that an appropriate selection of the secant plane allows a correct estimation of two positive Lyapunov exponents (LEs) from even a single sequence of return times. We propose a generalized approach for extracting dynamics from point processes that allows avoiding spurious identification of the dynamical regime caused by artifacts.