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81.
Kseniya N. MarkvichevaDmitry S. Bilan Natalia M. MishinaAndrey Yu. Gorokhovatsky Leonid M. VinokurovSergey Lukyanov Vsevolod V. Belousov 《Bioorganic & medicinal chemistry》2011,19(3):1079-1084
Hydrogen peroxide is an important second messenger controlling intracellular signaling cascades by selective oxidation of redox active thiolates in proteins. Changes in intracellular [H2O2] can be tracked in real time using HyPer, a ratiometric genetically encoded fluorescent probe. Although HyPer is sensitive and selective for H2O2 due to the properties of its sensing domain derived from the Escherichia coli OxyR protein, many applications may benefit from an improvement of the indicator’s dynamic range. We here report HyPer-2, a probe that fills this demand. Upon saturating [H2O2] exposure, HyPer-2 undergoes an up to sixfold increase of the ratio F500/F420 versus a threefold change in HyPer. HyPer-2 was generated by a single point mutation A406V from HyPer corresponding to A233V in wtOxyR. This mutation was previously shown to destabilize interface between monomers in OxyR dimers. However, in HyPer-2, the A233V mutation stabilizes the dimer and expands the dynamic range of the probe. 相似文献
82.
Introduction
Hand osteoarthritis (OA) is associated with pain, reduced grip strength, loss of range of motion and joint stiffness leading to impaired hand function and difficulty with daily activities. The effectiveness of different rehabilitation interventions on specific treatment goals has not yet been fully explored. The objective of this systematic review is to provide evidence based knowledge on the treatment effects of different rehabilitation interventions for specific treatment goals for hand OA.Methods
A computerized literature search of Medline, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), ISI Web of Science, the Physiotherapy Evidence Database (PEDro) and SCOPUS was performed. Studies that had an evidence level of 2b or higher and that compared a rehabilitation intervention with a control group and assessed at least one of the following outcome measures - pain, physical hand function or other measures of hand impairment - were included. The eligibility and methodological quality of trials were systematically assessed by two independent reviewers using the PEDro scale. Treatment effects were calculated using standardized mean difference and 95% confidence intervals.Results
Ten studies, of which six were of higher quality (PEDro score >6), were included. The rehabilitation techniques reviewed included three studies on exercise, two studies each on laser and heat, and one study each on splints, massage and acupuncture. One higher quality trial showed a large positive effect of 12-month use of a night splint on hand pain, function, strength and range of motion. Exercise had no effect on hand pain or function although it may be able to improve hand strength. Low level laser therapy may be useful for improving range of motion. No rehabilitation interventions were found to improve stiffness.Conclusions
There is emerging high quality evidence to support that rehabilitation interventions can offer significant benefits to individuals with hand OA. A summary of the higher quality evidence is provided to assist with clinical decision making based on current evidence. Further high-quality research is needed concerning the effects of rehabilitation interventions on specific treatment goals for hand OA. 相似文献83.
Saevarsdottir S Ding B Steinsson K Grondal G Valdimarsson H Alfredsson L Klareskog L Padyukov L 《Arthritis research & therapy》2011,13(2):R65
Introduction
Previous studies have provided inconsistent results on whether variants in the MBL2 gene, coding for the complement-activating mannan-binding lectin (MBL) protein, associate with rheumatoid arthritis (RA). We re-evaluated this in context of the main environmental and genetic risk factors (smoking, HLA-DRB1 'shared epitope' (SE), PTPN22*620W), which predispose to rheumatoid factor (RF) and/or anti-citrullinated-protein antibody (ACPA)-positive RA. 相似文献84.
Leonid Fedorenko Sergey Mamykin Oksana Lytvyn Yulia Burlachenko Boris Snopok 《Plasmonics (Norwell, Mass.)》2011,6(2):363-371
The physical mechanisms of metallic nanoparticles formation by laser technology were studied. The system air/Au film/glass
was irradiated by laser at the conditions of surface plasmon resonance. A surface electromagnetic wave was excited in Kretchmann
configuration by the fundamental and second harmonics of the Q-switched YAG/Nd+3 laser with pulse power density close to the threshold of melting. Nanostructuring of Au film was observed only for the second
harmonic (λ = 0.532 μm) irradiation at the surface plasmon polariton resonance (SPR) conditions. Estimations were done using the interference
model of the differently directed plasmon polariton waves excited by a surface electromagnetic wave on the metal surface.
It was shown that a regular pattern of locally heated spots can be formed in a metallic film by pulsed laser irradiation.
The spatial distribution of this pattern is close to the period of interference. The observed effect of laser nanofragmentation
is explained by the self-organization of plasmon polariton subsystem in the process of Au nanoparticles formation at high
laser intensity levels. These methods open new possibilities for nanostructured surfaces formation utilizing simple self-organization
processes. 相似文献
85.
Yury V. Rubin Leonid F. Belous Аnatolij А. Yakuba 《Journal of molecular modeling》2011,17(5):997-1006
To study M-DNA molecular structure (such DNA with transition metal ions placed between the nucleic bases is able to conduct
the electric current) and its conductivity mechanisms, we carried out ab initio quantum-mechanical calculations of electronic and spatial structures, thermodynamic characteristics of adenine-thymine (АТ)
and guanine-cytosine (GC) base pair complexes with Zn2+ and Ni2+. To take into account the influence of the alkaline environment, calculations for these complexes were also carried out with
hydroxyl and two water molecules. Computations were performed at MP2 level of theory using 6–31+G* basis set. Analogous calculations
were carried out for (AC)(TG) stacking dimer of nucleic acid base pairs with two Zn2+. The calculation of the interaction energy in complexes has shown the preference of locating the metal ion (instead of the
imino proton) between bases in M-DNA. The electronic transition energy calculation has revealed the reduction of the first
singlet transition energy in АТ and GC complexes with Ni2+ from 4.5 eV to 0.4 - 0.6 eV. Ni2+ orbitals take part in the formation of HOMO and LUMO on the complexes investigated. It was shown that charges of metal ions
incorporated into complexes with nucleic bases and in dimer decrease significantly. 相似文献
86.
Furlan A Monzani V Reznikov LL Leoni F Fossati G Modena D Mascagni P Dinarello CA 《Molecular medicine (Cambridge, Mass.)》2011,17(5-6):353-362
ITF2357 (givinostat) is a histone deacetylase inhibitor with antiinflammatory properties at low nanomolar concentrations. We report here a phase I safety and pharmacokinetics trial in healthy males administered 50, 100, 200, 400 or 600 mg orally. After 50 mg, mean maximal plasma concentrations reached 104 nmol/L 2 h after dosing, with a half-life of 6.9 h. After 100 mg, maximal concentration reached 199 nmol/L at 2.1 h with a half-life of 6.0 h. Repeat doses for 7 consecutive days of 50, 100 or 200 mg resulted in nearly the same kinetics. There were no serious adverse effects (AEs) and no organ toxicities. However, there was a dose-dependent but transient fall in platelets. After 7 daily doses of 50 or 100 mg, the mean decrease in platelets of 17 and 25% was not statistically significant and returned to baseline within 14 d. Blood removed from the subjects after oral dosing was cultured ex vivo with endotoxin, and the release of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, IL-1Ra, interferon (IFN)-γ and IL-10 was determined. Maximal reduction in IL-1β, TNFα, IL-6 and IFNγ was observed 4 h after dosing but returned to baseline at 12 h. There was no significant reduction in IL-1Ra or IL-10. With daily dosing, the fall in cytokine production in blood cultures observed on day 7 was nearly the same as that of the first day. We conclude that dosing of 50 or 100 mg ITF2357 is safe in healthy humans and transiently but repeatedly reduces the production of proinflammatory cytokines without affecting production of antiinflammatory cytokines. 相似文献
87.
Ardanov Pavlo Ovcharenko Leonid Zaets Iryna Kozyrovska Natalia Pirttilä Anna Maria 《Biological Control》2011,56(1):43-49
Priming plants by non-pathogenic bacteria allows the host to save energy and to reduce time needed for development of defense reaction during a pathogen attack. However, information on the role of endophytes in plant defense is limited. Here, the ability of endophytic bacteria to promote growth and resistance of potato plants towards infection by the necrotroph Pectobacterium atrosepticum was studied. A Pseudomonas sp. strain was selected due to antagonism towards bacterial pathogens and a Methylobacterium sp. strain because of efficient plant colonization. The aim of this study was to find if there is any correlation between plant growth promotion and induction of resistance by endophytes of potato, as well as to study the putative mechanisms of endophytes interacting with the plant during resistance induction. Both tested strains promoted growth of potato shoots but only the Pseudomonas sp. increased potato resistance towards the soft rot disease. Induction of disease resistance by the Methylobacterium sp. was inversely proportional to the size of bacterial population used for inoculation. The plant antioxidant system was moderately activated during the induction of resistance by the biocontrol strains. qPCR data on expression of marker genes of induced systemic resistance and acquired systemic resistance in endophyte-infected Arabidopsis plants showed activation of both salicylic acid and jasmonate/ethylene-dependent pathways after challenge inoculation with the pathogen. We suggest that some endophytes have the potential to activate both basal and inducible plant defense systems, whereas the growth promotion by biocontrol strains may not correlate with induction of disease resistance. 相似文献
88.
89.
A rapid series of synchronous cell divisions initiates embryogenesis in many animal species, including the frog Xenopus laevis. After many of these cleavage cycles, the nuclear to cytoplasmic ratio increases sufficiently to somehow cause cell cycles to elongate and become asynchronous at the mid-blastula transition (MBT). We have discovered that an unanticipated remodeling of core metabolic pathways occurs during the cleavage cycles and the MBT in X. laevis, as evidenced by widespread changes in metabolite abundance. While many of the changes in metabolite abundance were consistently observed, it was also evident that different female frogs laid eggs with different levels of at least some metabolites. Metabolite tracing with heavy isotopes demonstrated that alanine is consumed to generate energy for the early embryo. dATP pools were found to decline during the MBT and we have confirmed that maternal pools of dNTPs are functionally exhausted at the onset of the MBT. Our results support an alternative hypothesis that the cell cycle lengthening at the MBT is triggered not by a limiting maternal protein, as is usually proposed, but by a decline in dNTP pools brought about by the exponentially increasing demands of DNA synthesis. 相似文献
90.