Interchangeability of class I and II fumarases in an obligate methanotroph Methylotuvimicrobium alcaliphilum 20Z.

The methanotrophic bacterium Methylotuvimicrobium alcaliphilum 20Z is an industrially promising candidate for bioconversion of methane into value-added chemicals. Here, we have study the metabolic consequences of the breaking in the tricarboxylic acid (TCA) cycle by fumarase knockout. Two fumarases belonging to non-homologous class I and II fumarases were obtained from the bacterium by heterologous expression in Escherichia coli. Class I fumarase (FumI) is a homodimeric enzyme catalyzing the reversible hydration of fumarate and mesaconate with activities of ~94 and ~81 U mg-1 protein, respectively. The enzyme exhibited high activity under aerobic conditions, which is a non-typical property for class I fumarases characterized to date. The calculation of kcat/S0.5 showed that the enzyme works effectively with either fumarate or mesaconate, but it is almost four times less specific to malate. Class II fumarase (FumC) has a tetrameric structure and equal activities of both fumarate hydration and malate dehydration (~45 U mg-1 protein). Using mutational analysis, it was shown that both forms of the enzyme are functionally interchangeable. The triple mutant strain 20Z-3E (ΔfumIΔfumCΔmae) deficient in the genes encoding the both fumarases and the malic enzyme accumulated 2.6 and 1.1 mmol g-1 DCW fumarate in the medium when growing on methane and methanol, respectively. Our data suggest the redundancy of the metabolic node in the TCA cycle making methanotroph attractive targets for modification, including generation of strains producing the valuable metabolites.

2-(2-(Dimethylamino)vinyl)-4H-pyran-4-ones as Novel and Convenient Building-Blocks for the Synthesis of Conjugated 4-Pyrone Derivatives.

A straightforward approach for the construction of the new class of conjugated pyrans based on enamination of 2-methyl-4-pyrones with DMF-DMA was developed. 2-(2-(Dimethylamino)vinyl)-4-pyrones are highly reactive substrates that undergo 1,6-conjugate addition/elimination or 1,3-dipolar cycloaddition/elimination followed by substitution of the dimethylamino group without ring opening. This strategy includes selective transformations leading to conjugated and isoxazolyl-substituted 4-pyrone structures. The photophysical properties of the prepared 4-pyrones were determined in view of further design of novel merocyanine fluorophores. A solvatochromism was found for enamino-substituted 4-pyrones accompanied by a strong increase in fluorescence intensity in alcohols. The prepared conjugated structures demonstrated valuable photophysical properties, such as a large Stokes shift (up to 204 nm) and a good quantum yield (up to 28%).

Clinical and laboratory peculiarities of children's state with chronic tonsilitis on type 1 diabetes.

OBJECTIVE: The aim: Improvement of early diagnostics quality and efficiency of chronic pharyngeal diseases (CPD) treatment in children with DM-1 by studying the clinical and laboratory features of the disease course and complex therapy administration. PATIENTS AND METHODS: Materials and methods: A comprehensive examination of 707 children with diabetes mellitus-1, aged 3 to 18, was conducted, which determined clinical and laboratory features of their state in the presence and absence of chronic tonsillitis (CT). RESULTS: Results: Using microbiological and cytological examination of the palatine tonsils (PT) crypts, the leading role of microbial associations in the pathogenesis of HT in the formation of immune inflammation was determined, their influence on the local immunity indices was defined. Significant disturbances of the microcirculatory bed (MCB) in the presence of HT in children with DM-1, direct correlation between CPD and the presence of vascular glomeruli, changes in the retinal capillary structure (r = 0,332; p <0,05) according to biomicroscopy bulbar conjunctiva (BMBC) data were determined. The study of psycho-emotional state in children with CT and DM-1 was conducted, along with applied psycho-corrective program, which significantly reduces the manifestations of aggressiveness, aggression, and frustration reactions in them. CONCLUSION: Сonclusions: A non-invasive complex of the study of PT state on changes of local immunity indices, microbiocenosis and cytological data for correction of CPD course was developed, which allows to obtain faster compensation of CT and contributes to patients' quality of life improvment.

Cytokine and immunoglobulin spectra of tissue extracts from tonsils of children with hypertrophy and chronic tonsillitis.

OBJECTIVE: The aim: To compare the content of α and γ-interferons, interleukins 1ß ,4, 10, IgA, IgG, as well as the level of the general forms of immune complexes in tissue extracts from tonsils of children with hypertrophy and chronic tonsillitis. RESULTS: Results: In tissue extracts from tonsils with CT, there is a predominance of inflammation factors, potential sensitization, and the development of immunopathological reactions. The presence of inflammation is indicated by elevated levels of interleukin-1ß, immunoglobulin G. High levels of interleukin-4 may indicate that both HPT and CT have a tendency to increase sensitization to microbial and other antigens. CONCLUSION: Conclusion: The results indicate a significant difference in the qualitative and quantitative state of inflammation factors and allergy in case of HPT and CT. In tonsils with CT, there predominate both simple and allergic inflammations, as well as immunopathological reactions.

Integral scoring scale as a basis for an objective assessment of the state of patients with chronic tonsillitis and the effectiveness of their treatment.

OBJECTIVE: Introduction: Currently, the methods of integrated assessment of patient's condition based on scoring of separate multidirectional changes in subjective clinical and objective laboratory parameters are used in medical science more and more often. The aim: Based on the identified differences in clinical manifestations and immunological indicators of patients of different age with chronic tonsillitis and patients with no signs of ENT pathology, to develop an integral scoring scale as a basis for an objective assessment of the state of patients with CT and the effectiveness of their treatment. PATIENTS AND METHODS: Materials and methods: The clinical signs and immunological factors were evaluated. Patient's general information, such as age, the presence of allergies, was also taken into account. Based on the analysis of the data array, a scoring system for assessing the clinical and immunological state of patients was proposed. RESULTS: Results: The abnormalities in clinical and immunological assessment in adult population with no signs of ENT pathology (control group) are 2.75 times higher than in healthy children, while in case of chronic tonsillitis the differences between children and adults in terms of integral abnormalities are 1.66 (p<0.05). CONCLUSION: Conclusions: Integral scoring assessment of clinical and immunological tests makes it possible to provide more objective evaluation of the state of lymphoid tissue of tonsils and the immunity in patients with chronic tonsillitis, which may become an objective basis for choosing patient management strategy, as well as for estimating treatment efficacy.

Effectiveness of betahistine (48 mg/day) in patients with vestibular vertigo during routine practice: The VIRTUOSO study.

BACKGROUND: Vestibular vertigo is associated with substantially reduced quality of life. Betahistine is effective in improving vertigo-associated symptoms, with longer treatment periods leading to greater improvements; however, it is not known whether these effects persist after treatment cessation. METHODS: VIRTUOSO was a prospective, multinational, non-comparative, post-marketing observational programme investigating the effectiveness of betahistine (48 mg/day) and the course of vertigo after the discontinuation of treatment. Patients with vestibular vertigo who were prescribed 48 mg/day betahistine were enrolled in Russia and Ukraine. Treatment duration was up to 2 months, and patients were followed up for 2 months after discontinuation of betahistine. Efficacy endpoints included clinical response (assessed by change in vertigo severity), monthly attack frequency, and physician and patient grading of overall clinical response and improvement of vertigo-associated symptoms. RESULTS: Overall, 309 patients were enrolled and 305 completed the study. Clinical response was rated as good, very good or excellent in 74.1% of patients at end of treatment, with vertigo severity significantly decreased from baseline (p < 0.001). Monthly vertigo attack frequency decreased significantly during the 2 months of treatment (p < 0.001 from baseline) and further decreased during the 2-month follow-up (p < 0.001 from end of treatment). Overall, clinical response was graded as good or excellent by 94.4% of physicians and 95.4% of patients. Clinical improvement was considered either good or excellent by 82.6-90.5% of physicians and patients for nausea, vomiting and faintness. Only one adverse event was reported, with no serious adverse events. CONCLUSION: Our findings suggest that betahistine (48 mg/day) therapy is effective in treating vertigo in routine clinical settings. The observed effects persisted for 2 months after treatment cessation, suggesting that betahistine may facilitate lasting vestibular compensation.

Betahistine plus piracetam dual therapy versus betahistine monotherapy for peripheral vestibular vertigo: a confounder-corrected subanalysis of the OSVaLD study.

INTRODUCTION: This subanalysis compared the efficacy of betahistine plus piracetam dual therapy versus betahistine monotherapy using data from OSVaLD, a 3 month, open-label, observational study conducted in 2272 patients with peripheral vestibular vertigo. Of the 1898 patients included in the original efficacy population, 1076 were from countries where betahistine plus piracetam dual therapy was prescribed to >1 patient; 114 of these 1076 patients (11%) received the dual therapy and 567 (53%) were treated with betahistine monotherapy; these patients were selected for analysis. METHODS: Efficacy was assessed using the Dizziness Handicap Inventory (DHI) total and subscale scores. Propensity-score matching was used to correct potential differences in patient baseline characteristics between treatment groups. In addition, a subgroup analysis evaluated 103 patients treated with betahistine because of insufficient efficacy with their existing treatment. RESULTS: In the propensity-score matched, total-population evaluation, improvements in the DHI total and subscale scores were numerically greater in the betahistine plus piracetam group (n = 88) versus the betahistine group (n = 89) (DHI total, -42.9 vs. -37.6, respectively; DHI physical, -12.1 vs. -10.4; DHI emotional, -13.5 vs. -13.2) and statistically significant for the DHI functional score (-17.3 vs. -14.0, respectively, p = 0.01). The percentage of patients with no impairment at final visit was 27% with betahistine and 47% with betahistine plus piracetam; odds ratio: 2.3, 95% confidence interval: 1.3-2.4 (p = 0.007). Similar results were obtained in the subgroup analyses for patients whose current vertigo treatment was insufficient. The overall incidence of adverse events was low and similar in both groups, and there were no discontinuations due to drug-related adverse events. CONCLUSIONS: By using propensity-score matching, which controls for potential heterogeneity in patient baseline characteristics and small patient numbers, the results of this analysis suggest that combined betahistine and piracetam may be more effective than betahistine alone in patients with peripheral vestibular vertigo.

Effects and safety profile of betahistine in patients in the Russian contingent of OSVaLD, an open-label observational study in vestibular vertigo.

BACKGROUND: We report here data from the >200 patients recruited in Russia to take part in OSVaLD, a 12-week, open-label, post-marketing surveillance study of the response to betahistine 48 mg/day in vertigo of peripheral vestibular origin carried out in a total of 13 countries. METHODS: The primary efficacy endpoint was change in the Dizziness Handicap Inventory (DHI; 100-point scale). Changes in Hospital Anxiety and Depression Scale (HADS) and Medical Outcomes Study Short-Form 36, version 2 (SF-36v2(®)) scores were a priori secondary Outcomes. RESULTS: Total DHI score improved by 43 points during betahistine treatment. This aggregate improvement was equally distributed across the three domains of the DHI (physical, emotional, and functional; P<0.0001 for main and subscore changes from baseline). Statistically significant improvements versus baseline were also observed in mean HADS scores for anxiety and depression (both P<0.0001), and in the Physical Component Summary and Mental Component Summary scores of the SF-36v2 (both P<0.0001 versus baseline). Only one suspected adverse drug reaction was recorded in the Russian safety population (n=204), indicating that betahistine was well tolerated in those patients. CONCLUSION: Betahistine 48 mg/day was associated with clear improvements in well-configured and widely validated measures of health-related quality of life and an encouraging tolerability profile in patients in Russia who took part in OSVaLD.