Induced astigmatism and concomitant high myopia correction with femtosecond laser-assisted intrastromal MyoRing implantation

Purpose. Analysis of the results of astigmatism correction after penetrating keratoplasty and concomitant high myopia using the MyoRing ring implantation, clinical case as an example.Material and methods. Patient G., 51 years old, underwent surgery to correct astigmatism and concomitant high myopia. MyoRing was implanted in the right eye within corneal transplant limits using femtosecond laser-assisted intrastromal MyoRing implantation. Before the surgery uncorrected visual acuity at the operated eye was 0.01; corrected visual acuity 0.06; spherical component of refraction was (-)6.0 D, cylindrical component was (-)8.0 D. Mean keratometry in the right eye was 43.96 D. Corneal hysteresis was 6.5 mm Hg, corneal resistance factor was 5.5 mm Hg, cornea thickness in center was 529 mkm. The patient was followed up for one year.Results. In 12 months after the surgery visual acuity of the right eye without correction was 0.7 and 0.8 with correction. Spherical component was (-)1.0 D, cylindrical component was (-)2.0 D. Mean keratometry in the right eye was 35.10 D. Corneal hysteresis was 7.2 mm Hg, corneal resistance factor was 6.3 mm Hg, cornea thickness in center was 533 mkm. The patient was satisfied with the result of operation.Conclusion. Femtosecond laser-assisted intrastromal MyoRing implantation for correction induced astigmatism after penetrating keratoplasty and concomitant high myopia is efficient, safe and provides strengthening of biomechanical properties of the cornea besides refractive and visual effect

Control of Organic Impurities in Semisynthetic Antibiotics

In 2012, the European Medicines Agency (EMA) adopted a guideline, which divided all antibiotics into groups according to the manufacturing process and established acceptance criteria for organic impurities for each of the groups.The aim of the study was to justify the requirements and methodological approaches to setting the limits for organic impurities in semisynthetic antibiotics.Materials and methods: the authors analysed the requirements established by the leading world pharmacopoeias and the State Pharmacopoeia of the Russian Federation regarding the control of organic impurities in semisynthetic antibiotics, using the example of four semisynthetic antibiotics: doxycyline hyclate, clarithromycin, meropenem, and ceftriaxone. The study used the methods of comparative analysis and content analysis. Results: the study demonstrated that the organic impurity profiles of the analysed active substances and the corresponding finished medicinal products often differ significantly across the leading pharmacopoeias, either qualitatively or quantitatively. The Russian, European, and United States pharmacopoeias provide for the use of impurity reference standards in the test procedures for the determination of impurities in active substances of the semisynthetic antibiotics in question, whereas the Japanese Pharmacopoeia allows the use of non-compendial reference substances in the assessment of the chromatographic system separation power.Conclusions: the ability of a pharmacopoeial text to cover a variety of medicinal products coming to the Russian market from different countries has become a vital issue. This includes covering the impurity determination procedures, reference standards, and limits used, because general-purpose methods and limits do not always allow for correct assessment of impurity profiles in substances produced by different manufacturing processes. The current USP practice is to include various impurity control procedures in monographs on medicinal products, and the limits may also vary. This approach may be applied in the State Pharmacopoeia of the Russian Federation as well

Correction of postkeratoplastic astigmatism by intrastromal corneal segments implantation using a femtosecond laser

Background. After penetrating keratoplasty, mild to high induced corneal astigmatism was observed in each case. The existing choice of correction of postkeratoplastic astigmatism is aimed at fi nding an individual approach in order to compensate for it and not weaken the biomechanical properties of the corneal graft.The aim: to analyze the clinical, functional, and morphological results of postkeratoplastic astigmatism correction by implantation of intrastromal corneal segments using a femtosecond laser.Methods. 22 patients were examined before and 1 year after surgery. The operation was performed under local anesthesia: stage I – an intrastromal tunnel was formed using a femtosecond laser “Femto Visum” 1 MHz (Optosystems, Russia); stage II – the intrastromal corneal segments were implanted. The results were assessed using standard and special research methods using optical coherence tomography Visante OCT (Zeiss, Germany), keratotopography (Tomey-5, Japan), optical corneal analyzer ORA (Reichert, USA), laser tindalemetry FC-2000 (Kowa, Japan) and confocal microscope Confoscan-4 (Nidek, Japan).Results. Before the operation, uncorrected visual acuity averaged 0.09 ± 0.05, after a year – 0.50 ± 0.16; best corrected visual acuity – 0.30 ± 0.12 and 0.60 ± 0.05 respectively; cylindrical component of refraction – –10.29 ± 3.12 and –2.20 ± 0.64 D respectively; mean keratometry value – 43.59 ± 2.14 and 38.56 ± 1.75 D respectively; corneal hysteresis – 7.92 ± 1.22 and 8.95 ± 1.05 mm Hg respectively; corneal resistance factor – 7.01 ± 1.81 and 8.44 ± 1.44 mm Hg respectively; protein fl ux in the moisture of the anterior chamber – 2.97 ± 0.28 and 3.04 ± 0.24 f/ms respectively; endothelial cell density – 1521 ± 327 and 1475 ± 419 cells/mm2 respectively.Conclusion. Intrastromal corneal segments implantation into a corneal graft using a femtosecond laser has efficiency and safety method in correcting postkeratoplastic astigmatism

A process-based model of methane consumption by upland soils

This study combines a literature survey and field observation data in an ad initio attempt to construct a process-based model of methane sink in upland soils including both the biological and physical aspects of the process. Comparison is drawn between the predicted sink rates and chamber measurements in several forest and grassland sites in the southern part of West Siberia. CH4 flux, total respiration, air and soil temperature, soil moisture, pH, organic content, bulk density and solid phase density were measured during a field campaign in summer 2014. Two datasets from literature were also used for model validation. The modeled sink rates were found to be in relatively good correspondence with the values obtained in the field. Introduction of the rhizospheric methanotrophy significantly improves the match between the model and the observations. The Q10 values of methane sink observed in the field were 1.2-1.4, which is in good agreement with the experimental results from the other studies. Based on modeling results, we also conclude that soil oxygen concentration is not a limiting factor for methane sink in upland forest and grassland ecosystems.Peer reviewe

Контроль органических примесей в полусинтетических антибиотиках

In 2012, the European Medicines Agency (EMA) adopted a guideline, which divided all antibiotics into groups according to the manufacturing process and established acceptance criteria for organic impurities for each of the groups.The aim of the study was to justify the requirements and methodological approaches to setting the limits for organic impurities in semisynthetic antibiotics.Materials and methods: the authors analysed the requirements established by the leading world pharmacopoeias and the State Pharmacopoeia of the Russian Federation regarding the control of organic impurities in semisynthetic antibiotics, using the example of four semisynthetic antibiotics: doxycyline hyclate, clarithromycin, meropenem, and ceftriaxone. The study used the methods of comparative analysis and content analysis. Results: the study demonstrated that the organic impurity profiles of the analysed active substances and the corresponding finished medicinal products often differ significantly across the leading pharmacopoeias, either qualitatively or quantitatively. The Russian, European, and United States pharmacopoeias provide for the use of impurity reference standards in the test procedures for the determination of impurities in active substances of the semisynthetic antibiotics in question, whereas the Japanese Pharmacopoeia allows the use of non-compendial reference substances in the assessment of the chromatographic system separation power.Conclusions: the ability of a pharmacopoeial text to cover a variety of medicinal products coming to the Russian market from different countries has become a vital issue. This includes covering the impurity determination procedures, reference standards, and limits used, because general-purpose methods and limits do not always allow for correct assessment of impurity profiles in substances produced by different manufacturing processes. The current USP practice is to include various impurity control procedures in monographs on medicinal products, and the limits may also vary. This approach may be applied in the State Pharmacopoeia of the Russian Federation as well.В 2012 г. Европейским агентством по лекарственным средствам (European Medicines Agency, ЕМА) утверждено руководство, согласно которому все антибиотики разделены на группы в соответствии с технологией их получения. Для каждой группы установлены критерии приемлемости содержания органических примесей.Цель работы: обосновать требования и методические подходы к контролю органических примесей в лекарственных средствах полусинтетических антибиотиков.Материалы и методы: проведен анализ требований отечественной и ведущих зарубежных фармакопей к допустимому содержанию органических примесей в полусинтетических антибиотиках на примере четырех из них: доксициклина хиклат, кларитромицин, меропенем и цефтриаксон. В работе использовали методы сравнительного информационно-аналитического исследования и контент-анализа.Результаты: показано, что профиль органических примесей в монографиях ведущих зарубежных фармакопей на одноименную фармацевтическую субстанцию, а также лекарственный препарат, для каждого из исследуемых лекарственных средств, как правило, различается либо качественно, либо количественно. В методиках определения примесей для фармацевтических субстанций рассматриваемых полусинтетических антибиотиков согласно Государственной фармакопее Российской Федерации (ГФ РФ), Европейской фармакопее и Фармакопее США предусмотрено применение стандартных образцов примесей, тогда как Японская фармакопея для оценки разделительной способности хроматографической системы допускает использование веществ, которые не являются фармакопейными стандартными образцами.Выводы: актуальным вопросом становится способность фармакопейного стандарта учитывать многообразие лекарственных средств, поступающих на российский рынок из разных стран. Это касается используемых методик определения примесей, применения стандартных образцов, норм, поскольку единая методика и нормы не всегда позволяют корректно оценивать профиль примесей в субстанциях, полученных различным способом. Фармакопея США в настоящее время практикует включение в монографии на лекарственные средства различных методик для контроля примесей, при этом могут различаться также и нормы. Такой подход может быть применен и в ГФ РФ

Risk factors for development of lung fat embolism in casualties with severe mechanical trauma

One of the common and difficult to predict complications of injuries is fat embolism. Lethality rate is up to 67% even with intensive modern therapy. The variety of manifestations of fat embolism, the lack of a unified theory of its occurrence and development, the multiplicity and ambiguity of risk factors for fat embolism make it necessary to study in detail the risk factors for the development of fat embolism for its effective prevention and timely therapy. The results of forensic studies of corpses have been studied. The risk of fat embolism is correlated with the functional state of the organism at the time of injury, the peculiarities of injury, the presence and duration of medical care. Statistical processing of the obtained data using the program MedCalc Statistical for biomedical research, software manual (2014) has been performed. Direct negative regression of the ratio of soft tissue and internal organ damage to the degree of fat embolism has been reliably revealed. A slight direct positive regression between the extent of skeletal bone damage and the degree of fat embolism has been found. The development of fat embolism is associated with the presence of infectious and inflammatory processes in the lungs in 30-40% of cases. The fact of polytrauma does not significantly affect the degree of fat embolism. It was reliably determined that a high degree of fat embolism in a smaller part of cases was diagnosed with a combination of soft tissue damage and internal organs. Currently, the existing schemes of medical care for victims do not have a significant impact on the development of fat embolism. A detailed analysis of the provisions of biochemical and colloidal-chemical theories of fat embolism development is necessary for the development and implementation of recommendations for the prevention of embolism in certain categories of traumatological patients.Одним из часто встречающихся и сложно предсказуемых осложнений травм является жировая эмболия. Летальность, несмотря на интенсивную современную терапию, составляет до 67%. В настоящее время многообразие проявлений жировой эмболии, отсутствие единой теории ее возникновения и развития, а также множественность и неоднозначность факторов риска развития жировой эмболии определяют необходимость глубокого изучения факторов риска жировой эмболии для ее эффективной профилактики и своевременной терапии. Были изучены результаты судебно-медицинских исследований трупов. Для определения риска жировой эмболии учитывались функциональное состояние организма на момент травмы, особенности повреждения тканей и органов, наличие и длительность оказания медицинской помощи. Статистическая обработка полученных данных выполнена с помощью программы MedCalc Statistic for biomedical research, software manual 2014. достоверно выявлена прямая отрицательная регрессия соотношения объема повреждений мягких тканей и внутренних органов со степенью жировой эмболии; между объемом повреждения костей скелета и степенью жировой эмболии выявлена незначительная прямая положительная регрессия. развитие жировой эмболии сопряжено с наличием инфекционно-воспалительных процессов в легких в 30-40% случаев. Сделаны выводы о том, что факт политравмы достоверно практически не влияет на степень жировой эмболии, но достоверно выявлено, что высокая степень жировой эмболии в меньшей части случаев диагностирована при сочетании повреждения мягких тканей и внутренних органов. В настоящее время существующие схемы оказания медицинской помощи пострадавшим не оказывают существенного влияния на развитие жировой эмболии. В связи с вышесказанным необходим детальный анализ положений биохимической и коллоидно-химической теорий развития жировой эмболии для разработки и внедрения рекомендаций по профилактике эмболии у определенных категорий травматологических больных