CHANGES IN THE LEVELS OF ANGIOTENSIN II, ALDOSTERONE, AND FIBROBLAST GROWTH FACTOR IN PATIENTS WITH RHEUMATOID ARTHRITIS IN RELATION TO CLINICAL FEATURES

Angiotensin II, aldosterone, and fibroblast growth factor (FGF) stimulate neoangiogenesis, fibroblast proliferation, and elaboration of proinflammatory cytokines, which in turn contributes to increased pannus mass and the development of joint tissue destruction in rheumatoid arthritis (RA).Objective: to establish the specific features of changes in the blood levels of angiotensin II, aldosterone, and FGF in patients with RA in relation to the duration and severity of the disease.Subjects and methods. Examinations were made in 194 patients diagnosed with RA without comorbidity; the patients’ mean age was 47.7±10.2 years; the disease duration was 3.82±3.43 years. DAS28 scores for RA were calculated based on C-reactive protein levels. An enzyme immunoassay was used to determine the serum levels of anti-cyclic citrullinated peptide antibodies (ACCPA), angiotensin II, aldosterone, and FGF.Results and discussion. All the examinees were ascertained to have increases in the concentration of angiotensin II and aldosterone in blood by twice and in that of FGF by 2.5 times compared to the controls (p < 0.05). In patients with a RA duration of < 2 years, the blood level of angiotensin II was 25% higher than in those with a RA duration of > 5 years and the concentrations of aldosterone and FGF in patients with long-term RA were twice as high as in those with early RA. In patients with high RA activity, the blood level of angiotensin II was 1.5-fold higher than in those with low and moderate disease activity (p < 0.05). In patients with a high blood ACCPA level, the concentrations of angiotensin II, aldosterone, and FGF were 20, 30, and 25%, respectively, higher than in those with low ACCPA levels. The correlation of DAS28 with blood angiotensin II levels increased with enhanced RA activity. The high aldosterone and FGF values in RA patients are associated with the progression of joint radiographic changes

Third and fourth degree collisional moments for inelastic Maxwell models

The third and fourth degree collisional moments for $d$-dimensional inelastic Maxwell models are exactly evaluated in terms of the velocity moments, with explicit expressions for the associated eigenvalues and cross coefficients as functions of the coefficient of normal restitution. The results are applied to the analysis of the time evolution of the moments (scaled with the thermal speed) in the free cooling problem. It is observed that the characteristic relaxation time toward the homogeneous cooling state decreases as the anisotropy of the corresponding moment increases. In particular, in contrast to what happens in the one-dimensional case, all the anisotropic moments of degree equal to or less than four vanish in the homogeneous cooling state for $d\geq 2$.Comment: 15 pages, 3 figures; v2: addition of two new reference

Mathematical model of diesel engine characteristics for determining the performance of traction dynamics of wheel-type tractor

Wheel-type tractors carry out a range of processing operations, with the exception of early spring work, when caterpillar tractors are used to reduce the compaction effect on the soil. Therefore, to plan the costs and reserves associated with fuel consumption, it is necessary to have an estimate of the fuel economy of the tractor in basic agricultural operations. An objective assessment of fuel consumption requires a mathematical model that describes the fuel characteristics of the engine, taking into account the speed and load torque in a wide range of variation. Verification of the model is possible only with experimental data. Since the efficiency and fuel economy of a tractor depends not only on engine performance, but also on the perfection of the transmission, the running system and the rational choice of speed, it is necessary to take into account the time-varying nature of the tractor’s traction load. The complex of agricultural operations can be divided into characteristic cycles of load change over time. This principle is the basis of PowerMix test cycles, which are conducted on a concrete track to ensure repeatability of the experiment. The use of the variable load on the tractor in the PowerMix tests is positive, but in actual field tests the results may differ due to the instability of the soil properties. On the other hand, PowerMix field cycles can be taken as standard test loads in the simulation of tractor traction tests on the ground

Ингибитор ангиотензинпревращающего фермента в комплексном лечении ревматоидного а ртрита

Angiotensin-converting enzyme (ACE) inhibitors have anti-inflammatory and antiproliferative properties and can affect the processes of angiogenesis, by reducing the effects of angiotensin II (ATII). The use of ACE inhibitors in the combination therapy of rheumatoid arthritis (RA) can be also effective for monitoring disease activity and for reducing a cardiovascular risk.Objective: to evaluate the efficacy of an ACE inhibitor in the combination therapy of RA.Patients and methods. Eighty-four patients with RA and endothelial dysfunction were examined; the mean age was 40.12±10.2 years; the mean disease duration was 4.22±3.43 years. All the patients had a blood level of ATII of >9 pg/ml. Enzyme immunoassay was used to measure the levels of tumor necrosis factor-α (TNF-α) (Vector-Best, Russia), intercellular adhesion molecules 1 (ICAM-1) (Diaclone, France), vascular endothelial growth factor (VEGF) and ATII (Diagnostic, Canada). Wrist ultrasonography using the Doppler ultrasound apparatus ESAOTE MyLAB40 was carried out to assess synovial vascularization. The patients were divided into two groups. Group 1 included 43 patients who were assigned to receive standard therapy for RA according to the rheumatic disease treatment protocols; Group 2 comprised 41 patients who received the standard therapy plus ACE inhibitors 2.5–5 mg/day.Results. The use of ACE inhibitors in the 12-month combination therapy of RA patients led to an improvement in the endothelial regulation of vascular tone, to a decrease in the blood concentration of ICAM-1, to a reduction in the intensity of synovial angiogenesis and in the blood level of VEGF by 39%, and a more significant drop in the levels of CRP and TNF-? and in DAS28 by 1.2 scores as compared to those in the standard therapy.Ингибиторы ангиотензинпревращающего фермента (иАПФ) обладают противовоспалительными, антипролиферативными свойствами и могут влиять на процессы ангиогенеза через снижение эффектов ангиотензина II (АТІІ). Применение иАПФ в комплексной терапии ревматоидного артрита (РА) может быть эффективно и для контроля активности заболевания, и для снижения риска сердечно-сосудистых заболеваний.Цель исследования – оценка эффективности иАПФ в комплексной терапии РА.Пациенты и методы. Обследовано 84 больных РА с наличием эндотелиальной дисфункции, средний возраст – 40,12±10,2 года, средняя длительность РА – 4,22±3,43 года. У всех пациентов содержание АТІІ в крови составляло 9 пг/мл. С помощью иммуноферментного анализа определяли уровень фактора некроза опухоли α (ФНОα; «Вектор-Бест», Россия), молекул межклеточной адгезии (ICAM-1; Diaclone, Франция), сосудистого эндотелиального фактора роста (VEGF) и АТII (Diagnostic, Канада). Для оценки васкуляризации синовиальной оболочки (СО) выполняли УЗИ суставов кисти с допплером на аппарате ESAOTE MyLAB 40. Пациенты были разделены на две группы. В 1-ю группу вошли 43 пациента, которым была назначена стандартная терапия РА, согласно протоколам лечения ревматических заболеваний, во 2-ю группу – 41 пациент, получавший стандартную терапию с добавлением иАПФ 2,5–5 мг/сут.Результаты. Применение иАПФ в комплексной терапии больных РА в течение 12 мес приводило к улучшению показателей эндотелиальной регуляции сосудистого тонуса, снижению концентрации ICAM-1 в крови, уменьшению интенсивности ангиогенеза в СО и уровня VEGF в крови на 39%, более существенному снижению уровня СРБ, ФНОα и индекса активности DAS28 на 1,2 балла по сравнению с таковыми на фоне стандартной терапии

Performance of novel CaO-based sorbents in high temperature CO2 capture under RF heating

The problem of CO₂ mitigation on a small and medium scale can be resolved by developing a combined system of CO₂ capture and its consecutive conversion into valuable products. The first stage of CO₂ looping, however, should be reliable, effective and easy to control and radiofrequency heating, as a new advanced technology, can be used to improve the process. CO₂ absorption and desorption RF units can be installed within power plants and powered during the periods of low energy demand thus stabilizing the electrical grid. In this work, a CaO sorbent produced by template synthesis was studied as a sorbent for a CO₂ looping system under RF heating which offers short start-up times, highly controlled operation, high degree of robustness and low price. The sorbent reached its stable CO₂ capacity of 15.4 wt.% already after 10 temperature cycles (650/850 °C) under RF heating. Higher CO₂ desorption rate and lower degree of the sorbent sintering was observed under RF heating as compared to conventional heating

Жесткость сосудистой стенки у пациентов с анкилозирующим спондилитом, принимающих нестероидные противовоспалительные препараты

Changes in vessel wall stiffness are a sign of endothelial dysfunction and vascular remodeling at reversible, preclinical stages and may be a marker for cardiovascular disease, including in the use of nonsteroidal anti-inflammatory drugs (NSAIDs).Objective: to study changes in vessel wall stiffness indicators in patients with active ankylosing spondylitis (AS) without cardiovascular diseases during short- and long-term therapy with NSAIDS.Patients and methods. The investigation enrolled 164 AS patients aged older than 18 years. Of them 60 patients took amtolmetin guacil (AMG) daily for 3 months within the framework of the CORONA trial, the other 104 patients received nimesulide at least thrice weekly for 60 months (the index of NSAID use was 56%) within the framework of the PROGRESS study. Vessel wall stiffness indicators (augmentation indices and aortic pulse wave velocity (PWVao)) were studied in all the patients at baseline and after 3 (for those who took AMG) and 60 (for those who received nimesulde) months.Results. At baseline, AS activity and cardiovascular risk factors were comparable in the short- and long-term follow-up groups. The mean values of aortic augmentation index (AixAo) in the patients taking AMG were 13.5% [6.08; 22.08] at baseline and 14.25% [9.4; 24.25] after 3 months of therapy (p=0.18); PWVao was 7.7 [6.72; 9.41] and 8.46 [7.28; 9.96] m/sec, respectively (p=0.007). At the same time, PWVao was >10 m/sec only in 6 (10%) patients at baseline and in 12 (20%) following 3 months. In the group of patients taking NSAIDs long, AixAo was 21.5% [11.08; 34.25] at baseline and 18.25% [09.33; 26.28] at week 12 (p=0.3); PWVao was as high as 7.6 [6.56; 7.91] at baseline and 7.8 [7.22; 8.1] m/sec at week 12 (p=0.12). The PWVao of >10 m/sec was found in 20 (19.2%) patients at baseline and in 22 (21.15%) after 60 months of follow-up and treatment. The number of patients with unidirectional changes in vessel wall stiffness indicators did not differ in the 3- and 60-month use of NSAIDs. Conclusion. During 3-month NSAID therapy, the patients with AS showed a slight increase in PWVao in the absence of changes in the other indicators of vessel wall stiffness. At the same time, the mean values of PWVao remained within the normal range and its increase >10 m/sec was detected only in 20% of the patients. Long-term NSAID therapy in AS patients without cardiovascular diseases was unaccompanied by a change in the values of vessel wall stiffness and PWVao.Изменение жесткости сосудистой стенки является признаком дисфункции эндотелия и сосудистого ремоделирования на обратимых, доклинических этапах и может быть маркером поражения сердечно-сосудистой системы, в том числе при приеме нестероидных противовоспалительных препаратов (НПВП).Цель исследования – изучение изменений показателей жесткости сосудистой стенки у пациентов с активным анкилозирующим спондилитом (АС) без сердечно-сосудистых заболеваний на фоне краткосрочной и долгосрочной терапии НПВП.Пациенты и методы. В исследование включено 164 больных АС старше 18 лет. Из них 60 пациентов в рамках исследования КОРОНА в течение 3 мес ежедневно принимали амтолметин гуацил (АМГ), остальные 104 пациента в рамках исследования ПРОГРЕСС получали нимесулид в течение 60 мес не менее 3 раз в неделю (индекс приема НПВП составил 56%). У всех больных изучали показатели жесткости сосудистой стенки (индексы аугментации и скорость пульсовой волны в аорте – PWVAo) исходно, через 3 мес (для получавших АМГ) и через 60 мес (для получавших нимесулид).Результаты. Исходно активность АС, факторы сердечно-сосудистого риска в группах краткосрочного и долгосрочного наблюдения были сопоставимы. Исходно средние значения индекса аугментации в аорте (AixAo) у пациентов, принимавших АМГ, составляли 13,5% [6,08; 22,08], через 3 мес терапии – 14,25% [9,4; 24,25] (p=0,18); PWVAo – 7,7 м/с [6,72; 9,41] и 8,46 м/с [7,28; 9,96] соответственно (p=0,007). При этом только у 6 (10%) пациентов исходно и у 12 (20%) через 3 мес PWVAo была >10 м/с. В группе больных, длительно принимавших НПВП, AixAo исходно составлял 21,5% [11,08; 34,25], на 12-й неделе – 18,25% [09,33; 26,28] (p=0,3); PWVAo исходно достигала 7,6 м/с [6,56; 7,91], на 12-й неделе –7,8 м/с [7,22; 8,1] (p=0,12). При этом исходно PWVAo >10 м/с выявлена у 20 (19,2%) пациентов, а через 60 мес наблюдения и лечения – у 22 (21,15%). Количество пациентов с однонаправленными изменениями показателей жесткости сосудистой стенки при 3- и 60-месячном приеме НПВП не различалось.Выводы. На фоне 3-месячной терапии НПВП у больных АС отмечено незначительное повышение PWVAo при отсутствии изменения других показателей жесткости сосудистой стенки. При этом среднее значение PWVAo оставалось в пределах нормы, а повышение ее >10 м/с выявлено только у 20% пациентов. При длительной терапии у больных АС, не имеющих сердечно-сосудистых заболеваний, прием НПВП не сопровождался изменением показателей жесткости сосудистой стенки и PWVAo

ИЗМЕНЕНИЕ ФУНКЦИИ ПЕЧЕНИ У БОЛЬНЫХ СПОНДИЛОАРТРИТАМИ, ДЛИТЕЛЬНО ПРИНИМАВШИХ НЕСТЕРОИДНЫЕ ПРОТИВОВОСПАЛИТЕЛЬНЫЕ ПРЕПАРАТЫ: РЕЗУЛЬТАТЫ 10-ЛЕТНЕГО ПРОСПЕКТИВНОГО ИССЛЕДОВАНИЯ ПРОГРЕСС

Objective: to assess liver function changes in patients with spondyloarthritis (SpA) taking NSAIDs regularly over a long period.Patients and methods. The data obtained during a 10-year PROGRESS prospective single-center cohort study of functional status, activity, and comorbidity (including gastrointestinal tract diseases) in patients with SpA were analyzed. The data of 363 SpA patients receiving NSAIDs regularly over a long period and followed up for 10 years were also explored. The changes that had occurred over a decade in the liver enzyme levels, the number of discontinued NSAID treatments because of a persistent increase in liver enzyme levels, and the number of prescriptions of hepatoprotective agents were analyzed.Results. For 10 years, 18 patients with SpA discontinued their NSAID intake due to elevated liver enzyme levels (≥3 times greater than the reference value); during that time, the same increase in enzyme levels was observed in 2 healthy individuals (χ2 =1.39; p=0.2). In the patients with SpA as compared to the healthy individuals, the relative risk of abnormal liver function was 1.19 (95% CI, 1.009–1.405); odds ratio was 2.9 (95% CI, 0.65–12.95). There was no increased risk for discontinuation of some NSAIDs, including nimesulide (χ2 =0.03, p=0.85), the frequency of using hepatoprotective drugs was proved to be highest for diclofenac sodium, ibuprofen, nimesulide, and ketoprofen.Conclusion. The regular long-term (as long as 10 years) use of NSAIDs to treat SpA is associated with treatment discontinuation because of elevated enzyme levels in every 10 patients. The maximum rate of discontinuation of NSAIDs due to a persistent increase in liver enzyme levels is observed 6–8 years after their regular use, so long-term NSAID therapy requires continuous monitoring of hepatic safety. The longterm intake of nimesulide, as compared with other NSAIDs, is shown to be unassociated with the higher rate of its discontinuation because of worse liver function. Hepatoprotectors are less frequently prescribed to patients taking nimesulide than to those receiving diclofenac sodium or ibuprofen and more frequently to patients using meloxicam. In most cases, prescribing hepatoprotective agents to patients receiving NSAIDs does not require discontinuation of anti-inflammatory therapy. Длительное назначение нестероидных противовоспалительных препаратов (НПВП) требует повышенного внимания к безопасности лечения, в том числе в отношении функции печени.Цель исследования – оценка изменения функции печени у больных спондилоартритами (СпА), регулярно длительно применявших НПВП.Пациенты и методы. Проведен анализ данных, полученных в ходе 10-летнего проспективного когортного одноцентрового исследования, посвященного изучению функционального статуса, активности и сопутствующей патологии (включая заболевания желудочно-кишечного тракта) у пациентов со СпА (ПРОГРЕСС). Проанализированы данные 363 больных СпА, наблюдавшихся в течение 10 лет, регулярно длительно принимавших НПВП. Анализировали произошедшие за 10 лет изменения уровня печеночных ферментов, число отмен лечения НПВП по причине стойкого повышения уровня печеночных ферментов и число назначений гепатопротекторов.Результаты. За 10 лет у 18 больных СпА из-за повышения уровня печеночных ферментов (≥3 норм) был прерван прием НПВП, за это время такое же повышение уровня ферментов отмечено у 2 здоровых лиц (χ2 =1,39, p=0,2). Относительный риск нарушения функции печени у пациентов со СпА по сравнению со здоровыми составил 1,19 (95% ДИ 1,009–1,405), отношение шансов – 2,9 (95% ДИ 0,65–12,95). Не отмечено повышения риска отмены НПВП для отдельных препаратов, включая нимесулиды (χ2 =0,03, p=0,85), частота назначения гепатопротекторов оказалась максимальной для диклофенака натрия, ибупрофена, нимесулида и кетопрофена.Выводы. Регулярный длительный (до 10 лет) прием НПВП при СпА ассоциируется с отменой лечения из-за повышения уровня печеночных ферментов у 1 из 10 больных. Максимальная частота отмен НПВП вследствие стойкого повышения уровня печеночных ферментов отмечается через 6–8 лет их регулярного приема, поэтому длительная терапия НПВП требует постоянного мониторинга печеночной безопасности. Прием препаратов нимесулида в долгосрочной перспективе не ассоциируется с большей частотой их отмен из-за ухудшения функции печени по сравнению с другими НПВП. Пациентам, принимающим нимесулид, гепатопротекторы назначаются реже, чем пациентам, получающим диклофенак натрия или ибупрофен, и чаще, чем пациентам, принимающим мелоксикам. В большинстве случаев назначение гепатопротекторов на фоне приема НПВП не требует отмены противовоспалительной терапии.