Considerations for the Bioanalytical Part of Equivalence Studies of Biosimilar Nadroparin Calcium

According to current regulatory views, a comparative study of the pharmacodynamics (PD) of low molecular weight heparin (LMWH) products and confirmation of their equivalence require comparing three PD markers: the anti-Xa activity, the anti-IIa activity, and the tissue factor pathway inhibitor (TFPI) concentration. The aim of this study was to analyse the features specific to the bioanalytical part of an equivalence study of a nadroparin calcium biosimilar after single subcutaneous administration. Material and methods: the anti-Xa and anti-IIa activity values and TFPI content were determined in human plasma samples obtained after single subcutaneous administration of the test and the reference product in the same dose, using commercially available reagent kits and pre-validated assays. The authors calculated the main PD parameters (surrogate pharmacokinetic markers), namely the maximum activity or concentration (Amax or Cmax), time to maximum activity or concentration (Tmax), area under the activity–time (or concentration–time) curve (AUC ), and half-life period (T1/2), by means of model-independent statistical moment analysis and carried out further statistical testing of the parameters. Results: the anti-Xa activity and TFPI concentration results provided for  the  possibility  of  calculating  and  comparing  the PD parameters (Amax or Cmax, AUC0-24, AUC0-∞, Tmax, T1/2) and estimating the confidence intervals that are necessary to confirm the bioequivalence of the studied products. The anti-IIa activity data had a characteristic pattern of slight fluctuations around one level, which prevented the calculation and comparison of PD parameters. Conclusion: the study identified specific features to consider when planning comparative PD studies of nadroparin calcium products. Firstly, it is feasible to divide samples into two test aliquots (one for anti-Xa and anti-IIa activity determination, the other for TFPI analysis) at the moment of collection in order to perform the analytical step correctly. Secondly, there is no need in full validation for the bioanalytical assays of the anti-Xa and anti-II activity and TFPI content in human plasma validated in the concentration ranges of 0.024–0.182 IU/mL, 0.0069–0.052 IU/mL and 1.56–100 ng/mL, respectively; a confirmation that the active ingredient does not interfere with the analytical procedure is adequate for the purpose. Finally, the data obtained may not allow for calculating PD parameters and comparing confidence intervals for all three markers. The listed considerations may be relevant for other LMWH products as well

Чувствительность барорецепторов и состояние автономной нервной системы у пациентов с хроническими нарушениями сознания

Purpose of the study: to examine sensibility of baroreceptors and the autonomic nervous in the passive orthostatic test in patients with chronic impairment of consciousness due to severe brain damage and determine their role in the rehabilitation process.Materials and methods. The study included 30 patients with long-term impairment of consciousness due to severe brain damage (group 1), 10 of them being in the vegetative state (VS) and 20 being in the minimally conscious state (MCS). Craniocerebral trauma was the main cause of severe damage in that group (53% of patients). The comparison group included 24 patients with focal neurological symptoms caused predominantly — 79.2% of cases — by cerebrovascular disorders (group 2). The control group (group 3) consisted of 22 healthy volunteers of a comparable age. All measurements were done with the help of a Task Force Monitor 1030i (CNSystem, Austria) in the course of passive orthostatic test at 0°–30°–60°–0°. Changes in the power of low-frequency (LFS) and highfrequency spectrum (HFS) of heart rate variability and baroreceptors sensibility (BRS) were analyzed. Statistical analysis was carried out using Statistica-10 software. Significance of inter-group differences on unrelated samples was determined by the Mann–Whitney U-test. Differences between groups were considered significant at P 0.05.Results. Maximal background values of BRS were found in the control group. In group 1 and 2 patients, considerable decrease of that index was noted, which was proportional to the brain damage severity. Similar dynamics was observed for the indices of autonomic nervous system sensibility (LFS and HFS). The main trend of orthostatic changes of BRS, LFS, and HFS was characterized by progressive decrease of the indices with increase of the patients’ angle of tilting and their return to the baseline level after the patients were put back into the horizontal position. 4 patients of group 1 (14%) displayed signs of orthostatic disorders upon tilting to 30°: in 3 cases, orthostatic hypotension was observed, and in one case the postural orthostatic tachycardia syndrome (POTS) was diagnosed. Those patients differed by lower BRS and higher sympathetic system activity (LFS) vs. the same indices of other patients in that group.Conclusion. Patients with chronic impairment of consciousness during the post-comatose period after a severe brain damage display a significant decrease of baroreceptors sensibility and autonomic nervous system disorders manifesting in significantly lower activity of the sympathetic and parasympathetic systems. The prominence of such disorders is associated with brain damage severity. Their risk of developing orthostatic hypotension during tilting towards a vertical position is higher in patients who have lower baroreceptors sensibility, and this should be taken into account beginning the process of their verticalization.Цель исследования: изучить чувствительность барорецепторов и автономной нервной системы при пассивной ортостатической пробе у пациентов с хроническими нарушениями сознания вследствие тяжелых повреждений головного мозга и определить их роль в реабилитационном процессе.Материалы и методы. В исследование включили 30 пациентов с длительными нарушениями сознания, вызванными тяжелыми повреждениями головного мозга (группа 1), 10 из которых были в вегетативном состоянии (ВС) и 20 — с синдромом малого сознания (СМС). Основной причиной тяжелых повреждений была черепно-мозговая травма (53% пациентов этой группы). В группу сравнения вошли 24 пациента с очаговой неврологической симптоматикой, основной причиной которой в 79,2% случаев были нарушения мозгового кровообращения (группа 2). Контрольную группу (группа 3) составили 22 здоровых добровольца сопоставимого возраста. Все измерения проводили с помощью монитора Task Force Monitor 1030i (CNSystem, Австрия) в процессе пассивной ортостатической пробы 0°–30°–60°–0°. Провели анализ изменений показателей мощности низкочастотного (НЧС) и высокочастотного спектров (ВЧС) вариабельности сердечного ритма и чувствительности барорецепторов (ЧБР). Статистический анализ провели с помощью пакета статистических программ «Statistica-10». Значимость межгрупповых различий несвязанных выборок определяли расчетом критерия Манна Уитни (Mann–Whitney U-test). Достоверными считали различия при достижении уровня статистической значимости p 0,05.Результаты. Максимальные фоновые значения ЧБР выявили в контрольной группе. У пациентов 1 и 2 групп отмечали значительное снижение этого показателя, пропорциональное тяжести повреждений головного мозга. Аналогичную динамику имели показатели чувствительности автономной нервной системы (НЧС и ВЧС). Основной тренд ортостатических изменений ЧБР, НЧС, ВЧС характеризовался прогрессивным снижением этих показателей при увеличивающемся угле наклона пациентов и с восстановлением их до исходного уровня после возврата пациентов в горизонтальное положение. У 4 пациентов группы 1 (14%) при выполнении наклона на 30° появились признаки ортостатических нарушений: в 3 случаях наблюдали ортостатическую гипотензию и в одном — синдром постуральной ортостатической тахикардии (СПОТ). Отличием этих пациентов были более низкая ЧБР и более высокие показатели активности симпатической системы (НЧС) по сравнению с показателями других пациентов данной группы.Заключение. У пациентов с хроническими нарушениями сознания в посткоматозном периоде после тяжелых повреждений головного мозга наблюдаются значительное снижение чувствительности барорецепторов и нарушения автономной нервной системы, выражающиеся в значительном снижении активности симпатической и парасимпатической систем. Степень этих нарушений ассоциирована с тяжестью повреждений головного мозга. Риск развития ортостатической гипотензии при вертикализации выше у пациентов с более низкой чувствительностью барорецепторов, что необходимо учитывать в начале процесса их вертикализации

Evidence of the Generation of Isosaccharinic Acids and Their Subsequent Degradation by Local Microbial Consortia within Hyper-Alkaline Contaminated Soils, with Relevance to Intermediate Level Radioactive Waste Disposal

The contamination of surface environments with hydroxide rich wastes leads to the formation of high pH (>11.0) soil profiles. One such site is a legacy lime works at Harpur Hill, Derbyshire where soil profile indicated in-situ pH values up to pH 12. Soil and porewater profiles around the site indicated clear evidence of the presence of the α and β stereoisomers of isosaccharinic acid (ISA) resulting from the anoxic, alkaline degradation of cellulosic material. ISAs are of particular interest with regards to the disposal of cellulosic materials contained within the intermediate level waste (ILW) inventory of the United Kingdom, where they may influence radionuclide mobility via complexation events occurring within a geological disposal facility (GDF) concept. The mixing of uncontaminated soils with the alkaline leachate of the site resulted in ISA generation, where the rate of generation in-situ is likely to be dependent upon the prevailing temperature of the soil. Microbial consortia present in the uncontaminated soil were capable of surviving conditions imposed by the alkaline leachate and demonstrated the ability to utilise ISAs as a carbon source. Leachate-contaminated soil was sub-cultured in a cellulose degradation product driven microcosm operating at pH 11, the consortia present were capable of the degradation of ISAs and the generation of methane from the resultant H2/CO2 produced from fermentation processes. Following microbial community analysis, fermentation processes appear to be predominated by Clostridia from the genus Alkaliphilus sp, with methanogenesis being attributed to Methanobacterium and Methanomassiliicoccus sp. The study is the first to identify the generation of ISA within an anthropogenic environment and advocates the notion that microbial activity within an ILW-GDF is likely to influence the impact of ISAs upon radionuclide migration

Comparative genomics and evolution of bacterial regulatory systems

Abstract: Recent advances in genome sequencing and development of comparative genomics techniques allow one to study evolution of regulation in prokaryotes at several different levels: microevolution of orthologous regulatory sites, changes in regulon content, evolution of interacting regulatory systems, and co-evolution of transcription factors and their binding signals. Regulatory interactions appear to be very dynamic in some cases and surprisingly stable in others. The review presents several examples where comparative analysis uncovered plausible scenarios of evolution of regulatory systems

Особенности проведения биоаналитической части исследования эквивалентности биоаналогичного препарата надропарина кальция

According to current regulatory views, a comparative study of the pharmacodynamics (PD) of low molecular weight heparin (LMWH) products and confirmation of their equivalence require comparing three PD markers: the anti-Xa activity, the anti-IIa activity, and the tissue factor pathway inhibitor (TFPI) concentration.The aim of this study was to analyse the features specific to the bioanalytical part of an equivalence study of a nadroparin calcium biosimilar after single subcutaneous administration.Material and methods: the anti-Xa and anti-IIa activity values and TFPI content were determined in human plasma samples obtained after single subcutaneous administration of the test and the reference product in the same dose, using commercially available reagent kits and pre-validated assays. The authors calculated the main PD parameters (surrogate pharmacokinetic markers), namely the maximum activity or concentration (Amax or Cmax), time to maximum activity or concentration (Tmax), area under the activity–time (or concentration–time) curve (AUC), and half-life period (T1/2), by means of the model-independent statistical moment analysis and carried out further statistical testing of the parameters.Results: the anti-Xa activity and TFPI concentration results provided for the possibility of calculating and comparing the PD parameters (Amax or Cmax, AUC0-24, AUC0-∞, Tmax, T1/2) and estimating the confidence intervals that are necessary to confirm the bioequivalence of the studied products. The anti-IIa activity data had a characteristic pattern of slight fluctuations around one level, which prevented the calculation and comparison of PD parameters.Conclusion: the study identified specific features to consider when planning comparative PD studies of nadroparin calcium products. Firstly, it is feasible to divide samples into two test aliquots (one for anti-Xa and anti-IIa activity determination, the other for TFPI analysis) at the moment of collection in order to perform the analytical step correctly. Secondly, there is no need in full validation for the bioanalytical assays of the anti-Xa and anti-II activity and TFPI content in human plasma validated in the concentration ranges of 0.024–0.182 IU/mL, 0.0069–0.052 IU/mL and 1.56–100 ng/mL, respectively; a confirmation that the active ingredient does not interfere with the analytical procedure is adequate for the purpose. Finally, the data obtained may not allow for calculating PD parameters and comparing confidence intervals for all three markers. The listed considerations may be relevant for other LMWH products as well.Для сравнительного изучения фармакодинамики и подтверждения эквивалентности препаратов низкомолекулярных гепаринов (НМГ) согласно современным регуляторным требованиям необходимо сопоставить три фармакодинамических показателя: анти-Ха и анти-IIа активности и концентрацию ингибитора пути тканевого фактора (TFPI).Цель работы — анализ особенностей проведения биоаналитической части исследования эквивалентности биоаналогичного препарата надропарина кальция при подкожном введении.Материалы и методы: определение анти-Ха и анти-IIа активности НМГ и содержания TFPI в образцах плазмы крови человека, полученных после однократного подкожного введения тестируемого и референтного препаратов в одной дозе, выполнено с применением коммерчески доступных наборов реагентов и предварительно валидированных методик. Основные фармакодинамические параметры (суррогатные фармакокинетические маркеры): максимальная активность или концентрация (Amax или Сmax), время достижения максимальной активности или концентрации (Тmax), площадь под кривой «активность (концентрация) — время» (AUC), период полувыведения (T1/2) рассчитаны внемодельным методом статистических моментов и выполнена их дальнейшая статистическая обработка.Результаты: полученные результаты оценки анти-Ха активности и TFPI позволили рассчитать и сопоставить фармакодинамические параметры (Аmax или Cmax, AUC0-24, AUC0-∞, Тmax, T1/2), а также оценить доверительные интервалы, необходимые для подтверждения эквивалентности исследованных препаратов. Данные по значениям анти-IIа активности имели характер колебаний в пределах одного уровня, что не позволило рассчитать и сопоставить фармакодинамические параметры.Выводы: выявлены особенности, которые необходимо учитывать при планировании исследований фармакодинамики препаратов надропарина кальция: целесообразность разделения каждого образца при отборе с получением двух испытуемых аликвот (одна для определения анти-Ха и анти-IIа активностей, вторая — для анализа TFPI) для корректного выполнения аналитического этапа; достаточность подтверждения отсутствия мешающего влияния действующего вещества на аналитическую процедуру при валидации биоаналитических методик оценки анти-Ха активности, анти-IIа активности и содержания TFPI в плазме крови человека, валидированных в диапазоне концентраций 0,024–0,182 МЕ/мл, 0,0069–0,052 МЕ/мл и 1,56–100 нг/мл соответственно; возможность получения данных, не позволяющих рассчитать фармакодинамические параметры и сопоставить доверительные интервалы для всех трех фармакодинамических показателей. Указанные особенности могут быть характерны для других препаратов НМГ

Pathway-Based Evaluation in Early Onset Colorectal Cancer Suggests Focal Adhesion and Immunosuppression along with Epithelial-Mesenchymal Transition

Colorectal cancer (CRC) has one of the highest incidences among all cancers. The majority of CRCs are sporadic cancers that occur in individuals without family histories of CRC or inherited mutations. Unfortunately, whole-genome expression studies of sporadic CRCs are limited. A recent study used microarray techniques to identify a predictor gene set indicative of susceptibility to early-onset CRC. However, the molecular mechanisms of the predictor gene set were not fully investigated in the previous study. To understand the functional roles of the predictor gene set, in the present study we applied a subpathway-based statistical model to the microarray data from the previous study and identified mechanisms that are reasonably associated with the predictor gene set. Interestingly, significant subpathways belonging to 2 KEGG pathways (focal adhesion; natural killer cell-mediated cytotoxicity) were found to be involved in the early-onset CRC patients. We also showed that the 2 pathways were functionally involved in the predictor gene set using a text-mining technique. Entry of a single member of the predictor gene set triggered a focal adhesion pathway, which confers anti-apoptosis in the early-onset CRC patients. Furthermore, intensive inspection of the predictor gene set in terms of the 2 pathways suggested that some entries of the predictor gene set were implicated in immunosuppression along with epithelial-mesenchymal transition (EMT) in the early-onset CRC patients. In addition, we compared our subpathway-based statistical model with a gene set-based statistical model, MIT Gene Set Enrichment Analysis (GSEA). Our method showed better performance than GSEA in the sense that our method was more consistent with a well-known cancer-related pathway set. Thus, the biological suggestion generated by our subpathway-based approach seems quite reasonable and warrants a further experimental study on early-onset CRC in terms of dedifferentiation or differentiation, which is underscored in EMT and immunosuppression

Medical technology in rehabilitational counseling from the “Electronic Healthcare” perspective

Aim. To evaluate the readiness of acute coronary syndrome patients to distant physical rehabilitation (DPR) during the office rehabilitational counseling (ORC).Material and methods. Open retrospective study included data of 148 patients (117 males, 31 female), who had participated in ORC with the aim to include to DPR. Main part of ORC was conducted in the format of physician work with a computerized algorithm. Completeness of data to form the programs of physical rehabilitation (PR) was assessed manually with reviewing of the discharge summaries. Clinical status was assessed, and if necessary, the 6 minute walking test was conducted. Motivational component was assessed by the results of questionnaire “Program of calculation of motivational readiness of patients to adhere clinician recommendations”. Cognition was assessed with MMSE.Results. The part of “electronic” discharge summaries was 88,5%. Analysis of availability of epicrise data for algorithm modules showed that only 134 patients (97,3%) had complete data in clinical diagnosis. Also, an insufficiency was shown for number of stress tests with ECG registration: 22 (14,9%), but 96 (64,9%) with 6-minute test. In 30 patients (20,2%) the data on exercise tests was lacking. Data on PR regimen and related assessment of individual exercise tolerance was found in 34 (23% of ORC); and all who passed in-hospital stage. To the program of DPR about 1/3 (31,1%) of ORC participants were included. Under the framework of ORC, PR programs were created for all patients. By the results of investigation, a generalized clinical and instrumental characteristics of DPR patients were formulated, with added motivational and psychological specificities.Conclusion. It is found that in every 5th myocardial infarction patient discharged from hospital, there is lack of data on individual PR parameters that significantly reduces the ability of primary care physician in prescription and implementation of PR events. Usage of eHealth instruments at outpatient stage of cardiorehabilitation make it to solve these issues of ORC, which has as its tasks the PR programs formulation and evaluation of patient readiness for ORC participation

Physical rehabilitation after percutaneous coronary intervention: new perspectives of rehabilitation programme integration into ambulatory healthcare system

Aim. To study the effectiveness of ambulatory rehabilitation and prevention programmes in patients after percutaneous coronary intervention (PCI), with the use of computerized medical decision support system (MDSS) facilitating the choice of controlled physical training (CPT) regimen and the delivery of adequate recommendations on physical activity (PA) levels. Material and methods. This 12-month study included 194 patients (124 men and 70 women; mean age 53,5±3,6 years) with stable coronary heart disease (CHD), who underwent PCI (coronary angioplasty or coronary stenting). The CPT regimen was chosen, using the computerized MDSS. To perform the analysis of standard medical decisions, 25 doctors participated in a questionnaire survey. Results. The patients from the CPT group, demonstrated a significant increase in exercise capacity (EC) and mean exercise duration, an improvement in quality of life (QoL), and good pharmaceutical therapy compliance throughout the rehabilitation period. As shown by the questionnaire survey data, standard medical decisions were based, on average, on three clinical parameters; methodological errors were the most prevalent ones. Conclusion. The use of rehabilitation programmes, based on computerized MDSS, in ambulatory post-PCI patients ensures not only high effectiveness of rehabilitation and prevention measures, but also safety of physical training

PHYSICAL TRAINING IN THE REHABILITATION AND PREVENTION IN PATIENTS WITH ISCHEMIC HEART DISEASE AFTER PERCUTANEOUS CORONARY INTERVENTIONS: THE BORDERS OF EFFICIENCY AND SAFETY

Currently, it is proved that physical training (FT) should be a compulsory component of programmes for complex rehabilitation of patients with coronary heart disease after PCI. However, given the heterogeneity of clinical status of patients after conducting PCI medical rehabilitation should be personalized as for the choice of intensity and exposure of FT and with obligatory monitoring of their effectiveness and safety. This greatly extends the possibilities of wide use of FT at the stage of rehabilitation in the real clinical practice