Methods of the determination of inorganic arsenic species by stripping voltammetry in weakly alkaline media

Two methods are considered for the direct determination of trace amounts of As(III) and As(V) in solutions by stripping voltammetry (SVA) using an ensemble of gold microelectrodes (Au-MEA) previously developed by the authors of this paper. In both methods, analyzing a mixture of As(III) and As(V), analysts first record an SVA signal of As(III) in a supporting Na2SO3 electrolyte. To record an analytical SVA signal of As(V), in the first method one should use the reduction of As(V) to As(III) on the surface of an Au-MEA catalyzed by the system Mn(II)/Mn(0) and followed by the formation of As(0) and its anode dissolution. In the second method, the photoreduction of As(V) to As(III) in a Na2SO3 solution is conducted under UV irradiation followed by the reduction of As(III) to As(0) and its electrooxidation on Au-MEA. The two methods are compared taking into account their performance characteristics and interfering ions. To improve the reliability of the results of analysis at an insignificant increase in its cost, we propose the consecutive use of both methods. The procedures are simple and rapid, do not require the removal of dissolved oxygen or toxic reactants, and can be used for the analysis of aqueous solutions at the place of sampling. The results of analyses of real objects, snow, river water, and process solutions are presented

Fungal endophthalmitis

The article presents a clinical case of fungal endophthalmitis, the causative agent of which was Paecilomyces lilacinum. Patient M., female, 1947 year of birth was operated on for complicated cataract of the right eye. Two weeks later, she complained of decreased vision. A local anti-inflammatory therapy of the exudative reaction in the anterior chamber was carried out, therefore an improvement was achieved. Two weeks later, the patient again complained of visual impairment. Лечение было продолжено со сменой фунгицидных средств, обладающих большим Systemic and local anti-inflammatory and antibacterial therapy of exudative uveitis with the course of fluconazole for 15 days was carried out. Extended clinical and laboratory studies did not reveal any chronic inflammatory and immune diseases in the female patient. In connection with the further progression of the process, vitrectomy was performed with the removal of IOL and washing of the vitreous cavity with a solution of vancomycin. The achieved stabilization lasted short. There were appeared signs indicating a fungal etiology of the inflammatory process. Taking into account the previous long-term antibiotic therapy, yeast contamination was suggested. Despite the active treatment, there was a further deterioration of the eye. No pathogenic and conditionally pathogenic microflora growth was revealed as a result of seeding. Confocal microscopy revealed a filamentous structure of the mycelium in the thickness of the corneal stroma, which indicated infection with mold, not yeast fungi. Treatment was continued with a change of fungicidal agents with a large spectrum of action, as well as a silicone oil tamponade. The obtained culture was aimed at identification of the species and determination of sensitivity to fungicides in the medical scientific and practical center for tuberculosis control, Moscow. Cultural studies identified pathogenic microflora – Paecilomyces lilacinum, sensitive to ketoconazole. In connection with the spread of infection to the periorbital tissues, with the subsequent probability of systemic damage, an emergency enucleation of the eyeball was decided. This example indicates the need for increased alertness for fungal infection in cases of atypical flow of intraocular inflammation, the search for methods for early detection of the pathogen

Application of Dot-Immunoassay for Detection of Plague Agent Antigens in the Field Samples

CFU/ml) and soluble antigens (FI) − ≥ 4.8 ng/ml and high specificity, confirmed by the absence of false-positive reactions with five heterologous microorganisms. The test-systems were used for Y. pestis antigen detection in field material from the territory of the Altai mountain natural plague focus by dot-immunoassay with comparison of the received results in passive hemagglutination reaction. Test-systems possessed a number of advantages as compared to routine serological reactions and could be applied with success by practical public health services both in stationary and field conditions

Mesenchymal stromal cells of bone marrow and azathioprine in Crohn's disease therapy

Crohn's disease (CD) is a chronic, recurring disease of the gastrointestinal tract of unclear etiology. One of the new approaches to CD therapy is the use of the possibilities of stem cells, in particular, mesenchymal stromal cells (MSCs). Currently, the use of MSC in clinical practice for the treatment of chronic inflammatory and autoimmune diseases is being studied in patients who receive concomitant therapy with other immunomodulatory medications. Aim. To evaluate the effectiveness of MSCs therapy in patients with CD receiving azathioprine (AZA). Materials and methods. The study included 34 patients with inflammatory (luminal) form of CD. The 1st group of patients (n=15) received anti-inflammatory therapy using MSCs culture in combination with AZA. The 2nd group (n=19) received MSCs without AZA. The severity of the attack was assessed in points in accordance with the of Crohn's disease activity index (CDAI). Immunoglobulins (IgA, IgG, IgM), interleukins (IL) 1β, 4, 10, tumor necrosis factor-α (TNF-α), interferon-γ (INF-γ), transforming growth factor-1β (TGF-1β), C-reactive protein (CRP), platelets and erythrocyte sedimentation rate (ESR) at 2, 6 and 12 months from the beginning of MSCs therapy. Results. The initial mean CDAI in the 1st group was 337.6±17.1 points, in the 2nd group - 332.7±11.0 points (p=0.3). In both groups of patients there was a significant decrease in CDAI after 2 months. From the beginning of therapy MSCs: in the 1st group to 118.9±12.4 points, in the 2nd - 120.3±14.1 points (p=0.7), after 6 months - 110.3±11.1 and 114.3±11.8 points (p=0.8), respectively. After 12 months CDAI in the 1st group was 99.9±10.8 points, in the 2nd group it was 100.6±12.1 points (p=0.8). The level of IgA, IgG, IgM was significantly lower in the group of patients with a longer history of the disease and long-term ASA. After the introduction of MSC in both groups of patients with BC, there was a tendency for the growth of pro - and anti-inflammatory cytokines, with a significantly lower level of pro-inflammatory cytokines - INF-γ, TNF-α, IL-1β - in the 1st group, indicating potentiation of the immunosuppressive effect of MSCs and AZA, which provides a more pronounced anti-inflammatory effect. Conclusion. Transplantation of MSCs promotes an increase in the serum of patients with CD initially reduced concentration of IG, cytokines and restoring their balance as the onset of clinical remission. The combination with AZA has a more pronounced anti-inflammatory effect

Национальная система образования в России: проблемы и перспективы в контексте реформирования и глобализации

Like many others countries Russia try to change her own national education system in accordance with some global trends. The article analyses some reality and international assessments of this process and shows: those international investigations and education assessments are realized in Russia without necessary logic, so they became harmful for real educational process and national interests.Статья написана по материалам круглого стола “Российское образование: ключевые тенденции и задачи”, проходившего на социологическом факультете МГУ. Реформирование российского образования под воздействием фактора глобализации - одна из ключевых тем развернувшейся дискуссии

Potentiometric determination of nickel (II) with sodium diethyldithiocarbamate (NaDEDC)

The article presents the results of potentiometric titration of the solution containing Ni (II) by the solution of sodium diethylditheocarbamate (NaDEDC). The possibilities of carbon composite electrode (CCE) and certain ion-selective and metal electrodes as the sensors for potentiometric determination of ions were investigated. The conditions for potentiometric titration of nickel (reagent, pH, composition of supporting solution, efficient electrode, effect of interfering ions) using sensors have been studied and optimized. The titration curves were processed by the linearization method which provide determination of equivalence point with high accuracy

A community-maintained standard library of population genetic models

The explosion in population genomic data demands ever more complex modes of analysis, and increasingly, these analyses depend on sophisticated simulations. Recent advances in population genetic simulation have made it possible to simulate large and complex models, but specifying such models for a particular simulation engine remains a difficult and error-prone task. Computational genetics researchers currently re-implement simulation models independently, leading to inconsistency and duplication of effort. This situation presents a major barrier to empirical researchers seeking to use simulations for power analyses of upcoming studies or sanity checks on existing genomic data. Population genetics, as a field, also lacks standard benchmarks by which new tools for inference might be measured. Here, we describe a new resource, stdpopsim, that attempts to rectify this situation. Stdpopsim is a community-driven open source project, which provides easy access to a growing catalog of published simulation models from a range of organisms and supports multiple simulation engine backends. This resource is available as a well-documented python library with a simple command-line interface. We share some examples demonstrating how stdpopsim can be used to systematically compare demographic inference methods, and we encourage a broader community of developers to contribute to this growing resource.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Conditioned Pain Modulation Is Associated with Common Polymorphisms in the Serotonin Transporter Gene

BACKGROUND: Variation in the serotonin transporter (5-HTT) gene (SLC6A4) has been shown to influence a wide range of affective processes. Low 5-HTT gene-expression has also been suggested to increase the risk of chronic pain. Conditioned pain modulation (CPM)--i.e. 'pain inhibits pain'--is impaired in chronic pain states and, reciprocally, aberrations of CPM may predict the development of chronic pain. Therefore we hypothesized that a common variation in the SLC6A4 is associated with inter-individual variation in CPM. Forty-five healthy subjects recruited on the basis of tri-allelic 5-HTTLPR genotype, with inferred high or low 5-HTT-expression, were included in a double-blind study. A submaximal-effort tourniquet test was used to provide a standardized degree of conditioning ischemic pain. Individualized noxious heat and pressure pain thresholds (PPTs) were used as subjective test-modalities and the nociceptive flexion reflex (NFR) was used to provide an objective neurophysiological window into spinal processing. RESULTS: The low, as compared to the high, 5-HTT-expressing group exhibited significantly reduced CPM-mediated pain inhibition for PPTs (p = 0.02) and heat-pain (p = 0.02). The CPM-mediated inhibition of the NFR, gauged by increases in NFR-threshold, did not differ significantly between groups (p = 0.75). Inhibition of PPTs and heat-pain were correlated (Spearman's rho = 0.35, p = 0.02), whereas the NFR-threshold increase was not significantly correlated with degree of inhibition of these subjectively reported modalities. CONCLUSIONS: Our results demonstrate the involvement of the tri-allelic 5-HTTLPR genotype in explaining clinically relevant inter-individual differences in pain perception and regulation. Our results also illustrate that shifts in NFR-thresholds do not necessarily correlate to the modulation of experienced pain. We discuss various possible mechanisms underlying these findings and suggest a role of regulation of 5-HT receptors along the neuraxis as a function of differential 5-HTT-expression

Using C. elegans to discover therapeutic compounds for ageing-associated neurodegenerative diseases

Age-associated neurodegenerative disorders such as Alzheimer’s disease are a major public health challenge, due to the demographic increase in the proportion of older individuals in society. However, the relatively few currently approved drugs for these conditions provide only symptomatic relief. A major goal of neurodegeneration research is therefore to identify potential new therapeutic compounds that can slow or even reverse disease progression, either by impacting directly on the neurodegenerative process or by activating endogenous physiological neuroprotective mechanisms that decline with ageing. This requires model systems that can recapitulate key features of human neurodegenerative diseases that are also amenable to compound screening approaches. Mammalian models are very powerful, but are prohibitively expensive for high-throughput drug screens. Given the highly conserved neurological pathways between mammals and invertebrates, Caenorhabditis elegans has emerged as a powerful tool for neuroprotective compound screening. Here we describe how C. elegans has been used to model various human ageing-associated neurodegenerative diseases and provide an extensive list of compounds that have therapeutic activity in these worm models and so may have translational potential