Construction of stably maintained non-mobilizable derivatives of RSF1010 lacking all known elements essential for mobilization

<p>Abstract</p> <p>Background</p> <p>RSF1010 is a well-studied broad-host-range plasmid able to be mobilized to different bacteria and plants. RSF1010-derived plasmid vectors are widely used in both basic research and industrial applications. In the latter case, exploiting of mobilizable plasmids or even the plasmids possessing negligible mobilization frequency, but containing DNA fragments that could promote conjugal transfer, is undesirable because of biosafety considerations. Previously, several mutations significantly decreasing efficiency of RSF1010 mobilization have been selected. Nevertheless, construction of the RSF1010 derivative lacking all known loci involved in the conjugal transfer has not been reported yet.</p> <p>Results</p> <p>Novel non-mobilizable derivatives of RSF1010 lacking all known DNA sequences involved in the mobilization process have been obtained due to the exploiting of λRed-driven recombination between the plasmid and a constructed <it>in vitro </it>linear DNA fragment. To provide auto-regulated transcription of the essential replication gene, <it>repB</it>, the plasmid loci <it>oriT</it>, <it>mobC </it>and <it>mobA </it>were substituted by the DNA fragment containing P_{<it>lac</it>UV5}→<it>lacI</it>. Mobilization of the obtained RSFmob plasmid was not detected in standard tests. The derivative of RSFmob with increased copy number has been obtained after <it>lacI </it>elimination. High stability of both constructed plasmids has been demonstrated in <it>Escherichia coli </it>and <it>Pantoea ananatis</it>. Design of RSFmob allows easy substitution of P_{<it>lac</it>UV5}by any desirable promoter for construction of novel derivatives with changed copy number or host range.</p> <p>Conclusion</p> <p>Novel non-mobilizable derivatives of RSF1010 lacking all known DNA sequences involved in the mobilization process and stably maintained at least in <it>E. coli </it>and <it>P. ananatis </it>have been constructed. The obtained plasmids became the progenitors of new cloning vectors answering all biosafety requirements of genetically modified organisms used in scale-up production.</p

Biochemical changes of synovial fluid in patients with osteoporosis of knee joint of various etiology

The aim of this study was to perform comparative analysis of biochemical composition of synovial fluid in patients with osteoarthrosis of various etiology. Studies were conducted on samples of synovial fluid of patients which were divided into two groups. Thefirstgroup consisted of 16 patients with patellofemoral arthrosis of the 2nd stage, the second group included 54 patients with bilateral gonarthrosis. The samples of synovial fluid of 11 cadavers of suddenly dead people of both sexes (4 men and 7 women) of 23-79 years who didn't have articular pathology registered by an expert were considered as a norm. Conducted study testifies significant imbalance of prooxidant and antioxidant processes in the synovial fluid and development of oxidative stress the intensity of which depends on the severity of the pathological process but is regardless to its etiology

Alumosilicate ceramic proppants based on natural refractory raw materials

The sintering-strengthening effect of the additions of the highly ferrous bauxite (with Fe[2]O[3] content of 20-25 % in the calcined state) in the compositions with refractory clays was established. It was found that in the temperature range 1350-1500°C the additions of bauxite in amounts of 10-40% have a fluxing effect due to the iron oxide introduced with bauxite in compositions with clay. An increasing the bauxite additive in the amount of 50-70% ensures its strengthening effect by increasing the total content of the mullite of the prismatic habit in the firing products of composites with clay. Preliminary clay and bauxite calcination at 900 °С and an increase in the content of bauxite additive up to 50-70% in compositions with clay allow to produce aluminosilicate proppants with a bulk density of 1.62-1.65 g/сm{3} and compressive strength up to 52 MPa

РОМБЭНЦЕФАЛОСИНАПСИС: МР-СЕМИОТИКА И ДИФФЕРЕНЦИАЛЬНЫЙ ДИАГНОЗ

Rombencephalosynapsys (RES) is a rare variant of anomalies of the posterior cranial fossa structures characterized by dysplastic fusion of cerebellar hemispheres and absence or hypoplasia of cerebellar vermis. Purpose: to demonstrate the possibilities of modern neuroimaging in the RES diagnosis and to identify the main markers of the differential diagnosis in posterior fossa structures (PFS) anomalies. In the department of Radiology of Russian Children’s Clinical Hospital, we observed 3 patients with RES (1 girl and 2 boys). Patients age varied from 3 months to 9 years. The studies were performed on high-field MR system GE Discovery 750 W 3 T. Results: оn MRI in patients with RES we identified the spectrum of dysplastic anomalies of the vermis, from complete absence to partial aplasia with preservation of its anterior part. Also, there were 2 case with cerebellar dysplastic features, resemling RES. The transcerebellar sulci were estimated as the a clue diagnostic marker of RES. Conclusion: High-field MRI is the preferred diagnostic tool in the definition and differentiation of the developmental anomalies of the PFC in the children, especially in patients with RES.Диспластический профиль изменений структур задней черепной ямки достаточно обширен, однако особое место в ряду церебеллярных дисплазий, бесспорно, занимает ромбэнцефалосинапсис (РЭС) Это чрезвычайно редкая аномалия развития мозжечка, основное проявление которой — отсутствие долженствующего разобщения между церебеллярными гемисферами с частичной или полной агенезией червя. Цель работы: продемонстрировать возможности современной нейровизуализации в  идентификации ромбэнцефалосинапсиса и  обозначить основные маркеры дифференциального диагноза. В отделении лучевой диагностики ФГБУ РДКБ МЗ РФ мы наблюдали трех больных с  РЭС  — одну девочку и  двух мальчиков. Возраст пациентов составлял от  3 месяцев до  9 лет. Исследования выполнялись на магнитно-резонансном томографе Discovery 750 W компании GE с индукцией магнитного поля 3 Т. В результате исследования идентифицировали спектр диспластических изменений червя мозжечка, от его полного отсутствия до частичной аплазии с сохранением передней части. Кроме того, наблюдали 2 случая дисплазии мозжечка, мимикрирующей под РЭС. Благодаря высокому разрешению и отсутствию лучевой нагрузки высокопольная МРТ является предпочтительным диагностическим инструментом в определении и дифференциации редких аномалий структур ЗЧА у детей, в частности, такой спорадической патологии, как РЭС

A case of severe hyperparathyroidism in clinical practice. Case report

Disorders of the mineral balance often determine the symptoms, the severity of the course and the prognosis of many diseases. Primary hyperparathyroidism (PHPT) is a common endocrine disease caused by increased secretion of parathyroid hormone as a result of primary damage to the parathyroid glands. Diagnosis of PHPT is often difficult. Clinical signs of PHPT appear months or years after the onset of the disease, however, the presence of hypercalcemia serves as an early indication of the disease of the thyroid gland. Often, patients are observed for a long time by related specialists (rheumatologists, traumatologists-orthopedists, oncologists), which gives rise to a lot of problems consisting in the lack of adequate treatment and its result, the progression of the disease, disability, and a decrease in the quality of life. Often, patients are observed for a long time by related specialists (rheumatologists, orthopedic traumatologists, oncologists) under the “masks” of various pathologies (osteoporosis, recurrent urolithiasis, etc.), which gives rise to a lot of problems, consisting in an erroneous diagnosis, lack of adequate treatment and its result, progression of the disease, disability, and a decrease in the quality of life. Late diagnosis of PHPT leads to the development of severe complications (osteoporetic fractures, renal failure) and an increased risk of premature death. A clinical case of late diagnosis of PHPT at the stage of pronounced bone complications of the disease, which proceeded under the guise of osteoarthritis, is considered. According to the results of laboratory and instrumental studies, the following were revealed: hypercalcemia, a significant increase in the concentration of PTH, adenoma of the left lower parathyroid gland, hyperparathyroid osteodystrophy, and a decrease in bone mineral density. Surgical treatment was performed – selective parathyroidectomy with the development of hypocalcemia in the early postoperative period, which was stopped by taking calcium supplements and active vitamin D metabolites and is designed to help practitioners of various specialties to understand the issues of diagnosis of PHPT and effective care for patients

ВЛИЯНИЕ СИСТЕМ УДОБРЕНИЯ НА ПРОДУКТИВНОСТЬ СЕВООБОРОТА И АГРОХИМИЧЕСКИЕ ПОКАЗАТЕЛИ ДЕРНОВО-ПОДЗОЛИСТОЙ СУПЕСЧАНОЙ ПОЧВЫ

The influence of by products ploughing and mineral fertilizer doses on the crop rotation productivity and agrochemi-cal indicators of sod-podzolic sandy loam soil is studied. It’s established that autumn application of a compensatory dose of nitrogen to the straw didn’t ensure the increased productivity of crop rotation. It’s shown that application of correct doses of phosphorus and potassium fertilizers taking into account the phosphorus and potassium from a straw predecessor didn’t bring about the reduction of the productivity of crop rotation in comparison with the application of full doses of fertilizers and allowed saving P60 and K360.Изучено влияние запашки побочной продукции и доз минеральных удобрений на продуктивность севооборота и агрохимические показатели дерново-подзолистой супесчаной почвы. Установлено, что осеннее внесение компенсирующей дозы азота по соломе не обеспечило существенного увеличения продуктивности севооборота. Показано, что внесение скорректированных доз фосфорных и калийных удобрений с учетом фосфора и калия, высвобождающихся из соломы предшественника, не привело к снижению продуктивности севооборота по сравнению с применением полных доз удобрений и позволило сохранить Р60 и K360

Russian clinical practice guidelines «congenital adrenal hyperplasia»

Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive diseases characterized by a defect in one of the enzymes or transport proteins involved in the cortisol synthesis in the adrenal cortex. The most common form of CAH, which occurs in more than 90% of cases, is a 21-hydroxylase enzyme deficiency. The latter is subdivided into nonclassical and classic (salt-losing and virilizing) forms. The prevalence of classic forms of 21-hydroxylase deficiency ranges from 1: 14,000 to 1:18,000 live births worldwide. According to the data of neonatal screening in the Russian Federation, the prevalence of the disease in some regions ranges from 1: 5000 to 1: 12000, in the country as a whole - 1: 9638 live newborns. The non-classical form of CAH occurs more often - from 1: 500 to 1: 1000 among the general population. In second place is the hypertensive form of CAH - a deficiency of 11β-hydroxylase, which, according to the literature, occurs in about 1 per 100,000 newborns. These clinical guidelines were compiled by a professional community of narrow specialists, approved by the expert council of the Ministry of Health of the Russian Federation, and updated the previous version published in 2016. The clinical guidelines are based on systematic reviews, meta-analyses and original articles, and scientific work on this issue in the Russian Federation and other countries. The purpose of this document is to provide clinicians with the most up-to-date, evidence-based guidelines for the CAH diagnosis and treatmen

Исследование антиаритмической активности линейных алкоксифенилазаалканов на модели реперфузионных аритмий у крыс

The antiarrhythmic activity of bis-alkoxyphenyltriazaalkanes 1 and bis-alkoxyphenyldiazaalkanes 2 was analyzed in a model of reperfusion arrhythmia in rats. It was found that the key requirements for the compounds activity in this model are the use of 2,3,4 trimethoxyphenyl aromatic pharmacophores and the presence of a central nitrogen atom in the linker. The most active compounds were ALM-802 (trihydrochloride N1–(2,3,4-trimethoxybenzyl)-N2– {2-[(2,3,4-trimethoxybenzyl)amino]ethyl}-1,2-ethanediamine) and ALM-811 (N1-(2,3,4-trimethoxybenzyl)-N3-{3-[(2,3,4-trimethoxybenzyl)amino]ethyl}-1,3-propanediamine trihydrochloride), which significantly prevented the development of ventricular tachycardias and/or ventricular fibrillation.Проведён анализ взаимосвязи структуры и антиаритмической активности бис-алкоксифенилтриазаалканов 1 и бис-алкоксифенилдиаза-алканов 2 на модели реперфузионной аритмии у крыс. Установлено, что ключевыми требованиями к активности соединений на данной модели является использование 2,3,4-триметоксифенильных ароматических фармакофоров и наличие центрального атома азота в линкере. Наиболее активными соединениями оказались тригидрохлорид N1–(2,3,4-триметоксибензил)-N2–{2-[(2,3,4-триметоксибензил)амино]этил}-1,2-этандиамина и тригидрохлорид N1–(2,3,4-триметоксибензил)-N3–{3-[(2,3,4-триметоксибензил)амино]этил}-1,3-пропандиамина (шифры АЛМ-802 и АЛМ-811), значимо (p &lt; 0,001) препятствовавшие развитию желудочковых тахикардий и/или фибрилляций желудочков