Investigation of Magnetic Pulse Deformation of Powder Parts

Current article covers basics of powder compaction by electromagnetic impulse field and research results of sintered Fe powder part deformation process. This work is a joint research carried out by Riga Technical University (Latvia) and the Westsächsische Hochschule Zwickau (Germany)

ВЛИЯНИЕ МЕСТНЫХ ИНЪЕКЦИЙ ПРЕПАРАТОВ АКТИВНОЙ ФОРМЫ ВИТАМИНА D В ПАРАЩИТОВИДНЫЕ ЖЕЛЕЗЫ ПОД КОНТРОЛЕМ УЛЬТРАЗВУКОВОГО ИССЛЕДОВАНИЯ НА ДИНАМИКУ ЛАБОРАТОРНЫХ ПОКАЗАТЕЛЕЙ МИНЕРАЛЬНЫХ И КОСТНЫХ НАРУШЕНИЙ ПРИ ХРОНИЧЕСКОЙ БОЛЕЗНИ ПОЧЕК И НА ВЫЖИВАЕМОСТЬ ПАЦИЕНТОВ С РЕФРАКТЕРНЫМ ВТОРИЧНЫМ ГИПЕРПАРАТИРЕОЗОМ

Aim. To evaluate the effect of local vitamin D injections into parathyroid glands on laboratory markers and survival in refractory hyperparathyroidism. Materials and methods. A comparison of the dynamics of secondary hyperparathyroidism laboratory markers and survival was performed in 37 patients with local vitamin D injections into the parathyroid glands under ultrasound guidance and in 62 patients with PTH higher than 600 pg/ml without reduction in PTH levels by more than 10% during 6 months, who continued to receive available conservative therapy. The mean duration of follow-up for groups was 40.5 and 33.2 months, respectively.Results. In the local injection group (LIG) PTH level reduced by 347 ± 360 pg/ml (38%) during the first month after injection course, and by 214 ± 255 pg/ml (28%) between annual average levels before and after injection course, while in control group (CG) it rose by 84 ± 277 pg/ml (11%). In LIG phosphate level significantly reduced by 0.18 ± 0.24 mmol/l (9%) after injection course and annual average level did not change. In CG annual average phosphate level significantly rose by 0.15 ± 0.37 mmol/l (7%). Cumulative survival by Kaplan–Maier was significantly higher in LIG (p = 0.025). Differences in survival in univariate and multivariate Cox regression models were significantly associated only with the fact of local injections course (p =0.04 inboth models).Conclusion. In current clinical practice the application of ultrasound-guided local vitamin D injections into parathyroid glands in patients with refractory hyperparathyroidism leads to a better control over laboratory markers and to significantly improved survival.Цель. Выяснить влияние местных инъекций витамина D в паращитовидные железы на лабораторные маркеры вторичного гиперпаратиреоза и выживаемость. Материалы и методы. В популяции 834 пациентов, получавших заместительную терапию диализом в 8 диализных центрах Санкт-Петербурга с 2009-го по 2014 год, выполнено сравнение динамики лабораторных показателей и выживаемости 37 пациентов с выполненным местными инъекциями препаратов активной формы витамина D в паращитовидные железы (МИ) и 62 пациентов с устойчивым повышением ПТГ более 600 пг/мл при отсутствии снижения уровня ПТГ более чем на 10%, продолжавших получать доступную медикаментозную терапию. Средняя длительность наблюдения в группах составила 40,5 и 33,2 месяца соответственно. Результаты. В группе МИ отмечалось значимое снижение уровней ПТГ в первый месяц после выполнения курса инъекций на 347 ± 360 пг/мг (38%) и при сравнении среднегодовых значений до и после вмешательства на 214 ± 255 пг/мл (28%), в то время как в группе сравнения (ГС) отмечалось значимое повышение среднегодовых значений ПТГ на 84 ± 277 пг/мл (11%). Также в группе МИ отмечалось значимое снижение фосфатов сыворотки после инъекций в среднем на 0,18 ± 0,24 ммоль/л (9%) при отсутствии динамики среднегодовых значений, а в ГС зафиксировано нарастание среднегодовых значений фосфатов на 0,15 ± 0,37 ммоль/л (7%). В анализе по Каплану–Мейеру выживаемость оказалась значимо выше в группе МИ (p = 0,025). При сравнении выживаемости в регрессионных моделях по Коксу различия значимо (p = 0,04) были связаны только с фактом выполнения местных инъекций как в однофакторной, так и в многофакторной моделях.Выводы. В рамках текущей клинической практики применение местных инъекций препаратов активной формы витамина D в паращитовидные железы под контролем УЗИ при рефрактерном вторичном гиперпаратиреозе приводит к улучшению контроля лабораторных маркеров вторичного гиперпаратиреоза (ПТГ и фосфатов) и значимому улучшению выживаемости.

ОПРЕДЕЛЕНИЕ СРОКОВ НАЧАЛА ГЕМОДИАЛИЗА: РАЗРАБОТКА И ПОДТВЕРЖДЕНИЕ ШКАЛЫ START

Aim. The optimal time for initiating of chronic dialysis remains unknown. The scale for mortality risk assessment could help in decision-making concerning dialysis start timing.Methods. We randomly divided 1856 patients started dialysis in 2009–2016 into developmental and validation group (1:1) to create and validate scoring system «START» predicting mortality risk at dialysis initiation in order to fi nd unmodifi able and modifi able factors which could help in the decision-making of dialysis start. In the series of univariate regression models in the developmental set, we evaluated the mortality risk linked with available parameters: age, eGFR, serum phosphate, total calcium, hemoglobin, Charlson comorbidity index, diabetes status, urgency of start (turned to be signifi cant) and gender, serum sodium, potassium, blood pressure (without impact on survival). Similar hazard ratios were converted to score points.Results. The START score was highly predictive of death: C-statistic was 0.82 (95% CI 0.79–0.85) for the developmental dataset and 0.79 (95% CI 0.74–0.84) for validation dataset (both p < 0.001). On applying the cutoff between 7–8 points in the developmental dataset, the risk score was highly sensitive 81.1% and specifi c 67.9%; for validation dataset, the sensitivity was 78.9%, specifi city 67.9%. We confi rmed the similarity in survival prediction in the validation set to developmental set in low, medium and high START score groups. The difference in survival between three levels of START-score in validation set remained similar to that of developmental set: Wilcoxon = 8.78 (p = 0.02) vs 15.31 (p < 0.001) comparing low–medium levels and 25.18 (p < 0.001) vs 39.21 (p < 0.001) comparing medium–high levels.Conclusion. Developed START score system including modifi able factors showed good mortality prediction and could be used in dialysis start decision-making. Цель. Оптимальное время начала лечения гемодиализом (ГД) остается неопределенным. Создание шкалы для оценки рисков для пациента, начинающего диализ, поможет в принятии решения о сроках его начала.Методы. По данным регистра пациентов на заместительной почечной терапии проанализированы результаты лечения 1856 пациентов, начавших диализ в 2009–2016 гг. Случайным образом их разделили в соотношении 1:1 на группу разработки и группу подтверждения для создания прогностической шкалы оценки вероятности летального исхода при лечении программным гемодиализом (шкала START). При этом учитывали модифицируемые и немодифицируемые факторы риска. В серии регрессионных моделей с одной переменной в группе разработки шкалы мы оценивали риски смерти, связанные с доступными для анализа модифицируемыми и немодифицируемыми параметрами. Среди них значимыми оказались возраст, расчетная скорость клубочковой фильтрации (рСКФ), уровни фосфатов, общего кальция, гемоглобина, индекс коморбидности Чарлсон, наличие сахарного диабета, экстренность старта диализа. Пол, уровни натрия, калия, артериального давления не оказали влияния на выживаемость. Близкие по величине риски были преобразованы в баллы шкалы.Результаты. Шкала START продемонстрировала высокую предсказательную ценность в отношении риска смерти: AUC 0,82 (95% ДИ 0,79–0,85) для группы разработки шкалы и 0,79 (95% ДИ 0,74–0,84) для группы подтверждения (для обеих p < 0,001). Для точки отсечения 7–8 баллов чувствительность метода составила 81,1%, специфичность 69,9% для группы разработки и 78,9 и 67,9% соответственно – для группы подтверждения. Мы подтвердили близкие значения выживаемости пациентов в обеих группах для низких, средних и высоких значений шкалы START. Различия в выживаемости для подгрупп с тремя уровнями шкалы были близкими для групп разработки и подтверждения: критерий Wilcoxon = 8,78 (p = 0,02) vs 15,31 (p < 0,001) при сравнении выживаемости подгрупп низких и средних величин шкалы и 25,18 (p < 0,001) vs 39,21 (p < 0,001) при сравнении выживаемости подгрупп средних и высоких величин шкалы.Заключение. Разработанная шкала START, включающая модифицируемые факторы риска, продемонстрировала хорошую предсказательную ценность в отношении 5-летней летальности и может использоваться при принятии решения о времени старта диализа.

Global nephrology workforce: gaps and opportunities toward a sustainable kidney care system

The health workforce is the cornerstone of any health care system. An adequately trained and sufficiently staffed workforce is essential to reach universal health coverage. In particular, a nephrology workforce is critical to meet the growing worldwide burden of kidney disease. Despite some attempts, the global nephrology workforce and training capacity remains widely unknown. This multinational cross-sectional survey was part of the Global Kidney Health Atlas project, a new initiative administered by the International Society of Nephrology (ISN). The objective of this study was to address the existing global nephrology workforce and training capacity. The questionnaire was administered online, and all data were analyzed and presented by ISN regions and World Bank country classification. Overall, 125 United Nations member states responded to the entire survey, with 121 countries responding to survey questions pertaining to the nephrology workforce. The global nephrologist density was 8.83 per million population (PMP); high-income countries reported a nephrologist density of 28.52 PMP compared with 0.31 PMP in low-income countries. Similarly, the global nephrologist trainee density was 1.87 PMP; high-income countries reported a 30 times greater nephrology trainee density than low-income countries (6.03 PMP vs. 0.18 PMP). Countries reported a shortage in all care providers in nephrology. A nephrology training program existed in 79% of countries, ranging from 97% in high-income countries to 41% in low-income countries. In countries with a training program, the majority (86%) of programs were 2 to 4 years, and the most common training structure (56%) was following general internal medicine. We found significant variation in the global density of nephrologists and nephrology trainees and shortages in all care providers in nephrology; the gap was more prominent in low-income countries, particularly in African and South Asian ISN regions. These findings point to significant gaps in the current nephrology workforce and opportunities for countries and regions to develop and maintain a sustainable workforce

Increasing access to integrated ESKD care as part of Universal Health Coverage

The global nephrology community recognizes the need for a cohesive strategy to address the growing problem of end-stage kidney disease (ESKD). In March 2018, the International Society of Nephrology hosted a summit on integrated ESKD care, including 92 individuals from around the globe with diverse expertise and professional backgrounds. The attendees were from 41 countries, including 16 participants from 11 low- and lower-middle–income countries. The purpose was to develop a strategic plan to improve worldwide access to integrated ESKD care, by identifying and prioritizing key activities across 8 themes: (i) estimates of ESKD burden and treatment coverage, (ii) advocacy, (iii) education and training/workforce, (iv) financing/funding models, (v) ethics, (vi) dialysis, (vii) transplantation, and (viii) conservative care. Action plans with prioritized lists of goals, activities, and key deliverables, and an overarching performance framework were developed for each theme. Examples of these key deliverables include improved data availability, integration of core registry measures and analysis to inform development of health care policy; a framework for advocacy; improved and continued stakeholder engagement; improved workforce training; equitable, efficient, and cost-effective funding models; greater understanding and greater application of ethical principles in practice and policy; definition and application of standards for safe and sustainable dialysis treatment and a set of measurable quality parameters; and integration of dialysis, transplantation, and comprehensive conservative care as ESKD treatment options within the context of overall health priorities. Intended users of the action plans include clinicians, patients and their families, scientists, industry partners, government decision makers, and advocacy organizations. Implementation of this integrated and comprehensive plan is intended to improve quality and access to care and thereby reduce serious health-related suffering of adults and children affected by ESKD worldwide

Status of care for end stage kidney disease in countries and regions worldwide:international cross sectional survey

ObjectiveTo determine the global capacity (availability, accessibility, quality, and affordability) to deliver kidney replacement therapy (dialysis and transplantation) and conservative kidney management.DesignInternational cross sectional survey.SettingInternational Society of Nephrology (ISN) survey of 182 countries from July to September 2018.ParticipantsKey stakeholders identified by ISN's national and regional leaders.Main outcome measuresMarkers of national capacity to deliver core components of kidney replacement therapy and conservative kidney management.ResultsResponses were received from 160 (87.9%) of 182 countries, comprising 97.8% (7338.5 million of 7501.3 million) of the world's population. A wide variation was found in capacity and structures for kidney replacement therapy and conservative kidney management-namely, funding mechanisms, health workforce, service delivery, and available technologies. Information on the prevalence of treated end stage kidney disease was available in 91 (42%) of 218 countries worldwide. Estimates varied more than 800-fold from 4 to 3392 per million population. Rwanda was the only low income country to report data on the prevalence of treated disease; 5 (<10%) of 53 African countries reported these data. Of 159 countries, 102 (64%) provided public funding for kidney replacement therapy. Sixty eight (43%) of 159 countries charged no fees at the point of care delivery and 34 (21%) made some charge. Haemodialysis was reported as available in 156 (100%) of 156 countries, peritoneal dialysis in 119 (76%) of 156 countries, and kidney transplantation in 114 (74%) of 155 countries. Dialysis and kidney transplantation were available to more than 50% of patients in only 108 (70%) and 45 (29%) of 154 countries that offered these services, respectively. Conservative kidney management was available in 124 (81%) of 154 countries. Worldwide, the median number of nephrologists was 9.96 per million population, which varied with income level.ConclusionsThese comprehensive data show the capacity of countries (including low income countries) to provide optimal care for patients with end stage kidney disease. They demonstrate substantial variability in the burden of such disease and capacity for kidney replacement therapy and conservative kidney management, which have implications for policy

EFFECT OF ULTRASOUND-GUIDED DIRECT VITAMIN D INJECTIONS INTO PARATHYROID GLANDS ON LABORATORY MARKERS AND SURVIVAL OF PATIENTS WITH REFRACTORY SECONDARY HYPERPARATHYROIDISM

Aim. To evaluate the effect of local vitamin D injections into parathyroid glands on laboratory markers and survival in refractory hyperparathyroidism. Materials and methods. A comparison of the dynamics of secondary hyperparathyroidism laboratory markers and survival was performed in 37 patients with local vitamin D injections into the parathyroid glands under ultrasound guidance and in 62 patients with PTH higher than 600 pg/ml without reduction in PTH levels by more than 10% during 6 months, who continued to receive available conservative therapy. The mean duration of follow-up for groups was 40.5 and 33.2 months, respectively.Results. In the local injection group (LIG) PTH level reduced by 347 ± 360 pg/ml (38%) during the first month after injection course, and by 214 ± 255 pg/ml (28%) between annual average levels before and after injection course, while in control group (CG) it rose by 84 ± 277 pg/ml (11%). In LIG phosphate level significantly reduced by 0.18 ± 0.24 mmol/l (9%) after injection course and annual average level did not change. In CG annual average phosphate level significantly rose by 0.15 ± 0.37 mmol/l (7%). Cumulative survival by Kaplan–Maier was significantly higher in LIG (p = 0.025). Differences in survival in univariate and multivariate Cox regression models were significantly associated only with the fact of local injections course (p =0.04 inboth models).Conclusion. In current clinical practice the application of ultrasound-guided local vitamin D injections into parathyroid glands in patients with refractory hyperparathyroidism leads to a better control over laboratory markers and to significantly improved survival

THE ACHIEVABILITY OF TARGET CONVECTION VOLUMES IN ON-LINE HEMODIAFILTRATION

Aim. To evaluate the achievability of recommended convection volumes in hemodiafiltration (HDF) and impeding factors. Materials and methods. In short interventional one-center study among 67 stable prevalent dialysis patients we succeeded in achieving convection volume of more than 24 l/session in 60 patients (90%). Results. Substitution volume rose in the whole group from 21.1 ± 1.6 to 23.8 ± 1.2 l/session (p < 0.01). 12 patients, who didn`t achieve target volume had similar age, duration of renal replacement therapy and ultrafiltration rate as those who did. They differed from 55 patients who achieved target volume by substitution volume at first session in evaluation period (22.2 ± 1.7 vs. 23.6 ± 1.5 liters, р = 0.004), by transmembrane pressure (170 ± 40 vs. 146 ± 24 mmHg, р = 0.009) and by session duration (248 ± 15 vs. 262 ± 17 min, р = 0.0017). Blood flow rate also differed at the start of the study between the achievers and non-achievers: 353 ± 21 vs. 339 ± 19 ml/min, р = 0.035. The pressure in venous segment was lower in the achievers (154 ± 25 vs. 176 ± 36, р = 0.02) as well as transmembrane pressure (144 ± 24 vs. 164 ± 36, р = 0.014) which has been rising session by session in nonachievers. In non-achievers the membrane surface area was lower: 1.75 ± 0.2 vs. 1.91 ± 0.2 m2 (p = 0.02). In the multiple binary logistic regression model the session duration and membrane surface area were positive factors while the transmembrane pressure was negative one. Session prolonged by 15 min was associated with increase in relative chance to achieve target volume by 39% (95% CI 5–82%; р = 0.02). The membrane surface area enlarged by 0.1 m2 was linked with increase of chance by 4.2% (95% CI 0.2–8.4%; р = 0.04). The transmembrane pressure increased by 10 mmHg was associated with decreased chance to achieve target volume by 17% (95% CI 0–70%; р = 0.05). Conclusion. To achieve convection volume of 24 l/session one needs to afford effective blood flow rate, to increase the session duration and membrane surface area, avoiding high transmembrane pressure; severe comorbidity can hamper achieving target volume. Accumulating data of different studies are rather divergent in conclusions with regard to required target volume and ways to ensure its achievability, so study continuation is mandatory