Differential sensitivity of membrane-associated pyrophosphatases to inhibition by diphosphonates and fluoride delineates two classes of enzyme

Abstract1,1-Diphosphonate analogs of pyrophosphate, containing an amino or a hydroxyl group on the bridge carbon atom, are potent inhibitors of the H+-translocating pyrophosphatases of chromatophores prepared from the bacterium Rhodospirillum rubrum and vacuolar membrane vesicles prepared from the plant Vigna radiata. The inhibition constant for aminomethylenediphosphonate, which binds competitively with respect to substrate, is below 2 μM. Rat liver mitochondrial pyrophosphatase is two orders of magnitude less sensitive to this compound but extremely sensitive to imidodiphosphate. By contrast, fluoride is highly effective only against the mitochondrial pyrophosphatase. It is concluded that the mitochondrial pyrophosphatase and the H+-pyrophosphatases of chromatophores and vacuolar membranes belong to two different classes of enzyme

Неоднозначные результаты баллонной ангиопластики при стенозах центральных вен у пациентов на гемодиализе с нативной артериовенозной фистулой

Objective: to conduct comprehensive comparative analysis of the patency rate of native arteriovenous fistula (AVF) for central vein stenosis (CVS) after endovascular balloon angioplasty and palliative surgery. Materials and methods. The retrospective study included 80 patients with confirmed central vein stenosis: subclavian, brachiocephalic veins, inferior vena cava, or multiple lesions. The experimental group included 39 patients who underwent percutaneous balloon angioplasty. The control group included 41 patients who, for various reasons, did not do balloon angioplasty, but underwent palliative interventions: thrombectomy, proximalization of arteriovenous anastomosis, AVF blood flow-reducing surgical procedures. Results. Primary patency (time interval between the first intervention for CVS and the second intervention) in the experimental group was 61.5% [95% CI 44.5; 74.7] and 15.4% [95% CI 6.2; 28.3] at 6 and 12 months, respectively. In the control group, it was 39% [95% CI 24.3; 53.4] and 0% respectively. Hazard ratio (HR) 0.5337 [95% CI 0.3381; 0.8427], log-rank test p = 0.0011. No differences in functional primary patency (time interval between the start of using AVF and the first intervention for CVS) were found: 89.7% [95% CI 74.9; 96] and 30.8% [95% CI 17.3; 45.4] at 1 year and 3 years, respectively, in the experimental group, and 80.5% [95% CI 64.8; 89.7] and 24.4% [95% CI 12.7; 38.2] in the control group. There were no differences between the groups HR 0.7695 [95% CI 0.4952; 1.196], log-rank p = 0.2259. In the experimental group, strong negative correlation between primary patency and functional primary patency was detected: r = –0.627 [95% CI –0.787; –0.388], p < 0.0001. In the control group, no such correlation was found: r = 0.049 [95% CI –0.262; –0.351], p = 0.7599. Thus, the later CVS developed, the less effective balloon angioplasty was. Balloon angioplasty significantly increased duration of AVF use after first intervention for CVS (secondary patency): 84.6% [95% CI 68.9; 92.8], 66.7% [95% CI 49.6; 79.1] and 17.9% [95% CI 7.9; 31.3] at 6, 12 and 24 months, respectively in the experimental group. In the control group, it was 56.1% [95% CI 39.7; 69.6], 19.5% [95% CI 9.2; 32.7] and 0%. HR 0.4009 [95% CI 0.2481; 0.6477], log-rank p < 0.0001. Functional secondary patency (total duration of AVF use) was: 100%, 74.4% [95% CI 57.6; 85.3] and 12.8% [95% CI 4.7; 25.2] at 1, 3 and 5 years in the experimental group, and 95.1% [95% CI 81.9; 98.8], 36.6% [95% CI 22.3; 51] and 4.9% [95% CI 0.9; 14.5] in the control group. HR 0.5661 [95% CI 0.3598; 0.8906], log-rank p = 0.0067. Conclusions. 1. Central vein stenosis inevitably cuts vascular access from the ipsilateral side. 2. Balloon angioplasty allows to slightly prolong AVF use but it cannot radically change the long-term results of CVS treatment. 3. The outcome of balloon angioplasty greatly depends on the length of the period from the time the use of AVF started to the time CVS developed. 4. Multiple repeated balloon angioplasties are apparently justified in patients for whom creating a new vascular access might not be possible. 4. AVF volumetric blood flow velocity is an important factor determining the severity of CVS clinical manifestations and whether repeated surgical interventions are needed.Цель: провести комплексный сравнительный анализ показателей проходимости нативной артериовенозной фистулы (АВФ) при стенозе центральных вен (СЦВ) после эндоваскулярной баллонной ангиопластики и паллиативных оперативных вмешательств. Материалы и методы. В ретроспективное исследование включены 80 пациентов с подтвержденным стенозом центральных вен: подключичных, брахиоцефальных вен, нижней полой вены или множественным поражением. К основной группе были отнесены 39 пациентов, у которых выполнена чрескожная баллонная ангиопластика. К группе сравнения были отнесены 41 пациент, у которых по различным причинам баллонная ангиопластика не выполнялась, а проводились паллиативные вмешательства: тромбэктомия, проксимализация артериовенозного анастомоза, редукция кровотока по АВФ. Результаты. Первичная проходимость (интервал времени между первым вмешательством по поводу СЦВ и повторным вмешательством) составила 61,5% [95%ДИ 44,5; 74,7] и 15,4% [95%ДИ 6,2; 28,3] через 6 и 12 месяцев соответственно в основной группе, 39% [95%ДИ 24,3; 53,4] и 0% – в группе сравнения, HR 0,5337 [95%ДИ 0,3381; 0,8427], log-rank p = 0,0011. Мы не отметили различий в функциональной первичной проходимости (интервал времени между началом использования АВФ и первым вмешательством по поводу СЦВ): 89,7% [95%ДИ 74,9; 96] и 30,8% [95%ДИ 17,3; 45,4] через год и три года соответственно в основной группе, 80,5% [95%ДИ 64,8; 89,7] и 24,4% [95%ДИ 12,7; 38,2] – в группе сравнения. Различий между группами не было, HR 0,7695 [95%ДИ 0,4952; 1,196], log-rank p = 0,2259. В основной группе между первичной проходимостью и функциональной первичной проходимостью выявлена сильная отрицательная связь: r = –0,627 [95%ДИ –0,787; –0,388], p < 0,0001. В группе сравнения такой зависимости не выявлено: r = 0,049 [95%ДИ –0,262; –0,351], p = 0,7599. Таким образом, чем позднее развился СЦВ, тем меньше была эффективность баллонной ангиопластики. Баллонная ангиопластика позволила значительно увеличить продолжительность использования АВФ после первой операции по поводу СЦВ (вторичная проходимость): 84,6% [95%ДИ 68,9; 92,8], 66,7% [95%ДИ 49,6; 79,1] и 17,9% [95%ДИ 7,9; 31,3] через 6 и 12 и 24 месяца соответственно в основной группе, 56,1% [95%ДИ 39,7; 69,6], 19,5% [95%ДИ 9,2; 32,7] и 0% – в группе сравнения, HR 0,4009 [95%ДИ 0,2481; 0,6477], log-rank p < 0,0001. Функциональная вторичная проходимость составила (общая продолжительность использования АВФ): 100%, 74,4% [95%ДИ 57,6; 85,3] и 12,8% [95%ДИ 4,7; 25,2] через один, три и пять лет в основной группе, 95,1% [95%ДИ 81,9; 98,8], 36,6% [95%ДИ 22,3; 51] и 4,9% [95%ДИ 0,9; 14,5] – в группе сравнения, HR 0,5661 [95%ДИ 0,3598; 0,8906], log-rank p = 0,0067. Выводы. 1. Стеноз центральных вен неизбежно приводит к утрате сосудистого доступа с ипсилатеральной стороны. 2. Баллонная ангиопластика позволяет несколько продлить период использования АВФ, не способна радикально изменить долгосрочные результаты течения СЦВ. 3. На результаты баллонной ангиопластики значительное влияние оказывает продолжительность периода от момента начала использования АВФ до развития СЦВ. 4. Многократные повторные баллонные ангиопластики, по-видимому, оправданы у пациентов, возможность создания нового устойчивого сосудистого доступа у которых сомнительна. 4. Объемная скорость кровотока по АВФ является важным фактором, определяющим выраженность клинических проявлений СЦВ и потребность в повторных оперативных вмешательствах

СЪДЪРЖАНИЕ НА PB И CD В ПРАНА И НЕПРАНА ВЪЛНА ОТ ОВЦЕ ОТГЛЕЖДАНИ В РАЙОН С ПОВИШЕН ТЕХНОГЕНЕН КЛАРК

An ICP-ETAAS analyze of unwashed and washed sheep- wool for establishing of Pb and Cd have been conducted. A signifi cant difference in the contents of Pb (15.3- unwashed versus 8.15 mg/kg DM– washed wool) were established. The Cd – content were mean 0.69 (unwashed) versus 0.53 mg/kg DM– washed wool. No statistical differences were established. The authors conclude, that the environment infl uence signifi cant on the Pb- content of sheep- wool.Проведен е ICP-ETAAS анализ на прана и непрана овча вълна за установяване на Pb и Cd. Установени са достоверни разлики в съдържанията на Pb (15.3- непрана срещу 8.15 mg/kg АСВ- прана вълна). Средното съдържание на Cd е 0.69 (непрана) срещу 0.53 mg/kg АСВ (прана вълна). Разликите са статистически достоверни. Авторите заключват, че околното среда влияе достоверно върху съдържанието на Pb в овчата вълна

The effect of differences in the third domain of the glycoprotein E of tick-borne encephalitis virus of the Far Eastern, Siberian and European subtypes on the binding of recombinant D3 proteins with a chimeric antibody

Currently, a therapeutic drug based on recombinant antibodies for the prevention and treatment of tick-borne encephalitis virus (TBEV) is developed in ICBFM SB RAS, and the chimeric antibody ch14D5 is considered as one of the key components of this drug. It was previously shown that this antibody is directed to the domain D3 of the glycoprotein E of TBEV. It was previously shown that this antibody is able to protect mice from the European subtype of TBEV, strain “Absettarov”, and the presence of virus-neutralizing activity against the Far Eastern subtype of TBEV, strain 205 was also shown for this antibody. However, it remains unclear whether this antibody exhibits selectivity for different subtypes of TBEV. The aim of this study was to investigate the effect of amino acid sequence differences of recombinant D3 domains derived from the glycoprotein E of TBEV of the Far Eastern, Siberian and European subtypes on the binding of the protective antibody ch14D5 to these proteins. Using Western blot analysis and surface plasmon resonance, it was shown that ch14D5 antibody has the highest affinity (KD= 1.7±0.5 nM) for the D3 domain of the TBEV of the “Sofjin-Ru” strain belonging to the Far Eastern subtype of the virus. At the same time, the affinity of ch14D5 antibody for similar D3 proteins derived from “Zausaev”, “1528-99” and “Absettarov” strains of the Siberian and European subtypes of TBEV was noticeably lower (KD= 25±4, 300±50, 250±50 nM, respectively). In addition, information about the spatial arrangement of amino acid residues that are different for the studied recombinant proteins indicates that the epitope recognized by the ch14D5 antibody is in close proximity to the lateral ridge of D3 domain of E glycoprotein

Evidence and ideology as a rationale for light-therapy in Russia: from the Soviet Union to the present day.

Light therapy is still used to treat a number of common diseases in Russia. The practice is firmly anchored in history: Soviet clinical practice was divorced from the emerging field of evidence-based medicine. Medical researchers were cut off from international medical research and scientific literature, with much Soviet scientific activity based on a particular socialist ideology. In this study, the use of light therapy serves as a case study to explore tensions between international evidence-based medicine and practices developed in isolation under the Soviet Union, the legacy of which is to the detriment of many patients today. We used four different search methods to uncover scientific and grey literature, both historical and contemporary. We assessed the changing frequency of publications over time and contrasted the volume of literature on light therapy with more orthodox treatments such as statins and painkillers. Our search found an increasing number and comparatively large body of scientific publications on light therapy in the Russian language, and many publications emanating from prestigious Russian institutions. Combined with our analysis of the historical literature and our appraisal of 22 full text articles, this leads us to suggest that light therapy entered mainstream Soviet medical practice before the Stalinist period and still occupies an important position in contemporary Russian clinical practice. We propose that this outdated treatment survives in Russia in part due to the political, economic and social forces that helped to popularize it during Soviet times, and by the seeming justification offered by poorly executed studies

Inhibition of gastric H,K-ATPase activity and gastric epithelial cell IL-8 secretion by the pyrrolizine derivative ML 3000

BACKGROUND: ML 3000 ([2,2-dimethyl-6-(4-chlorophenyl)-7-phenyl-2,3-dihydro-1H-pyrrolizine-5-yl]-acetic acid) is an inhibitor of both cyclooxygenase and 5-lipoxygenase in vitro, and shows promise as a novel non-steroidal anti-inflammatory drug (NSAID). Unlike conventional NSAIDs which are associated with gastric ulcerogenic effects, ML 3000 causes little or no damage to the gastric mucosa, even though it significantly depresses gastric prostaglandin synthesis. METHODS: As part of an effort to clarify mechanisms underlying the gastric sparing properties of ML 3000, we studied the effects of ML 3000 on H,K-ATPase activity in vitro, on acid accumulation in isolated gastric parietal cells, and on IL-8 secretion by gastric epithelial cells in culture. RESULTS: SCH28080-sensitive H,K-ATPase activity in highly-purified pig gastric microsomes was dose-dependently inhibited by ML 3000 (IC(50) = 16.4 μM). Inhibition was reversible, and insensitive to ML 3000 acidification in the pH range 2.0–8.0. In rabbit gastric parietal cells, ML 3000 dose-dependently inhibited histamine-stimulated acid accumulation (IC(50) = 40 μM) and forskolin-stimulated acid accumulation (IC(50) = 45 μM). Lastly, in human gastric adenocarcinoma (AGS) cells, ML 3000 dose-dependently inhibited both baseline and IL-1β-stimulated (20 ng/ml) IL-8 secretion with IC(50)s of 0.46 μM and 1.1 μM respectively. CONCLUSION: The data indicate that ML 3000 affects acid-secretory mechanisms downstream of cAMP mobilization induced by histamine H(2) receptor activation, that it directly inhibits H,K-ATPase specific activity, and that baseline gastric epithelial cell IL-8 secretory inhibition may be mediated by ML 3000 inhibition of 5-lipoxygenase activity. We conclude that these gastric function inhibitory data may underlie the gastric sparing properties of ML 3000

Применение ингибитора JAK1 и JAK2 руксолитиниба в качестве пред- и посттрансплантационной терапии па% циентов с миелофиброзом

Primary myelofibrosis (PMF) is а chronic BCRABL–negative myeloproliferative disorder with progressive clinical course. Allogeneic stem cell transplantation is the only treatment optionin patients with PMF with curative potential. Most of PMF patients have active disease phase at the moment of alloHSCT. The Januskinase inhibitor ruxolitinib is effective in decreasingof tumor mass before alloHSCT. Here we report our experience in administration of ruxolitinib as pre and posttransplant therapy of patients with PMF as well as patients with polycythemia vera and essential thrombocythaemia with transformation into myelofibrosis.Первичный миелофиброз (ПМФ) – хроническое Ph-негативное миелопролиферативное заболевание, характеризующееся, как правило, непрерывно прогрессирующим течением. АллоТГСК в настоящий момент является единственным методом терапии, позволяющим излечить больных ПМФ. Однако большая часть пациентов на момент алло-ТГСК находится в активной фазе заболевания. Использование ингибиторов JAK позволяет уменьшить объем опухолевой массы перед аллоТГСК. Проанализирован опыт применения руксолитиниба в качестве пред и посттрансплантационной терапии пациентов с ПМФ, а также больных с истинной полицитемией и эссенциальной тромбоцитемией с трансформацией в миелофиброз

Identification of a tyrosine residue responsible for N-acetylimidazole-induced increase of activity of ecto-nucleoside triphosphate diphosphohydrolase 3

Chemical modification in combination with site-directed mutagenesis was used to identify a tyrosine residue responsible for the increase in ecto-nucleoside triphosphate diphosphohydrolase 3 (NTPDase3) nucleotidase activity after acetylation with a tyrosine-selective reagent, N-acetylimidazole. The NTPDase3 ATPase activity is increased more than the ADPase activity by this reagent. Several fairly well conserved tyrosine residues (252, 255, and 262) that are located in or very near apyrase conserved region 4a (ACR4a) were mutated. These mutants were all active, but mutation of tyrosine 252 to either alanine or phenylalanine eliminated the activity increase observed after N-acetylimidazole treatment of the wild-type enzyme. This suggests that the acetylation of tyrosine 252 is responsible for the increased activity. Stabilization of quaternary structure has resulted in increased enzyme activities for the NTPDases. However, mutation of these three tyrosine residues did not result in global changes of tertiary or quaternary structure, as measured by Cibacron blue binding, chemical cross linking, and native gel electrophoretic analysis. Nevertheless, disruption of the oligomeric structure with the detergent Triton X-100 abolished the increase in activity induced by this reagent. In addition, mutations that abolished the N-acetylimidazole effect also attenuated the increases of enzyme activity observed after lectin and chemical cross-linking treatments, which were previously attributed to stabilization of the quaternary structure. Thus, we speculate that the acetylation of tyrosine 252 might induce a subtle conformational change in NTPDase3, resulting in the observed increase in activity

Study of dynamics of the process e+e−→π+π−π0e^+e^-\to \pi^+\pi^-\pi^0 in the energy range 1.15--2.00 GeV

The dynamics of the process $e^+e^- \to \pi^+\pi^-\pi^0$ is studied in the energy region from 1.15 to 2.00 GeV using data accumulated with the SND detector at the VEPP-2000 $e^+e^-$ collider. The Dalitz plot distribution and $\pi^+\pi^-$ mass spectrum are analyzed in a model including the intermediate states $\rho(770)\pi$, $\rho(1450)\pi$, and $\omega\pi^0$. As a result, the energy dependences of the $\rho(770)\pi$ and $\rho(1450)\pi$ cross sections and the relative phases between the $\rho(770)\pi$ amplitude and the $\rho(1450)\pi$ and $\omega\pi^0$ amplitudes are obtained. The $\rho(1450)\pi$ cross section has a peak in the energy region of the $\omega(1650)$ resonance (1.55-1.75 GeV). In this energy range the contributions of the $\rho(770)\pi$ and $\rho(1450)\pi$ states are of the same order of magnitude. No resonance structure near 1.65 GeV is observed in the $\rho(770)\pi$ cross section. We conclude that the intermediate state $\rho(1450)\pi$ gives a significant contribution to the decay of $\omega (1650)\to\pi^+\pi^-\pi^0$, whereas the $\rho(770)\pi$ mechanism dominates in the decay $\omega(1420)\to\pi^+\pi^-\pi^0$.Comment: 9 pages, 7 figures, 3 table