Potential value of high-throughput single-cell DNA sequencing of Juvenile myelomonocytic leukemia: report of two cases.

Juvenile myelomonocytic leukemia (JMML) is a rare myeloproliferative disease of early childhood that develops due to mutations in the genes of the RAS-signaling pathway. Next-generation high throughput sequencing (NGS) enables identification of various secondary molecular genetic events that can facilitate JMML progression and transformation into secondary acute myeloid leukemia (sAML). The methods of single-cell DNA sequencing (scDNA-seq) enable overcoming limitations of bulk NGS and exploring genetic heterogeneity at the level of individual cells, which can help in a better understanding of the mechanisms leading to JMML progression and provide an opportunity to evaluate the response of leukemia to therapy. In the present work, we applied a two-step droplet microfluidics approach to detect DNA alterations among thousands of single cells and to analyze clonal dynamics in two JMML patients with sAML transformation before and after hematopoietic stem cell transplantation (HSCT). At the time of diagnosis both of our patients harbored only "canonical" mutations in the RAS signaling pathway genes detected by targeted DNA sequencing. Analysis of samples from the time of transformation JMML to sAML revealed additional genetic events that are potential drivers for disease progression in both patients. ScDNA-seq was able to measure of chimerism level and detect a residual tumor clone in the second patient after HSCT (sensitivity of less than 0.1% tumor cells). The data obtained demonstrate the value of scDNA-seq to assess the clonal evolution of JMML to sAML, response to therapy and engraftment monitoring.

[Ultrasound study in the diagnosis of small and large intestinal obstruction]. / Ul'trazvukovoe issledovanie v diagnostike tonko- i tolstokishechnoi neprokhodimosti.

The results of ultrasound study were analyzed in 148 and 26 patients with acute small and intestinal obstruction, respectively, the causes of the latter included different diseases of the intestine and abdominal organs. The commonest ultrasound symptoms based on the diameter of the bowel, on the thickness and structure of the intestinal wall, on the status of mucosal motility folds of intestinal loops and on the pattern of motility were defined. They enable one to differentiate large and small intestinal obstruction and to define its degree with a high degree of validity. Abdominal ultrasonography used in the emergency surgical setting may rapidly solve problem in the diagnosis of abnormal changes, differential mechanical and functional ileus in most cases. Dynamic ultrasound monitoring allows the efficiency of the treatment performed to be evaluated.

[Principles for optimizing and gauging certain processes in vaccine production technology. V. Complex approach to gauging processes involved in assuring aseptic conditions in incubators]. / Printsipy optimizatsii i masshtabirovaniia nekotorykh protsessov v tekhnologii vaktsinnykh proizvodstv. Soobshchenie V. O kompleksnom podkhode k masshtabirovaniiu protsessov, obespechivaiushchikkh dostizhenie asepticheskikh uslovii kul'tivatorakh.

The contamination of the cultivator with the extraneous microflora in the process of growing microorganisms in various apparatus has been shown to have the probabilistic character. The index of aseptic effectiveness is recommended for the comparative evaluation of the effectiveness of the processes which ensure the achievement and maintenance of aseptic conditions in the process of the cultivation of microorganisms in the laboratory and industrial equipment, as well as for changing the scale of the process.

[Evaluation of the existing sterilization regimens for dishware and fluids by the autoclaving method]. / Otsenka sushchestvuiushchikh rezhimov sterilizatsii posudy i zhidkostei metodom avtoklavirovaniia.

Analysis of the present conditions for autoclave sterilization of laboratory glassware and nutrient media showed that they were not well founded and that the assembly diagrams of the autoclaves did not meet the requirements to the apparatus providing aseptic conditions. Checking of the temperature fields revealed "week" points with respect to sterilization. The heating rate of the glassware and nutrient media was determined and the choice of the limiting point for the control of sterilization temperature in autoclaves was substantiated.

[Device for sampling and feeding under aseptic conditions]. / Ustroistvo dlia otbora prob i vvedeniia dobavok v asepticheskikh usloviiakh.

The scheme and operating principle of a device for sampling and feeding under aseptic conditions are discussed. The device provides sterility of the elements used for sampling and feeding and excludes the contact of the liquids with the environment. The results of the study on the device temperature fields substantiated the sterilization regime using the parameter of the aseptic efficient. The sterilization period is 10 minutes which decreases the steam consumption and increases the production efficiency.

[Collector device for apparatus hookup connections in microbiological manufacture]. / Kollektornoe ustroistvo montazhnykh skhem apparatov mikrobiologicheskikh proizvodstv.

A collector device developed on the basis of a holding tank is discussed. The working principle of the device, its characteristics and advantages as applied to microbiological industry are described. The use of the collector devices in the assembly diagrams of the apparatus provides reduction of the number of the piping fittings, the pipe-line length, the number of the sealing elements, heat evolution into the environment, and time of the apparatus servicing.

[Principles of optimization and scaling of certain processes in the vaccine production technology. 3. Method of determination of the optimal method of thermal sterilization of sugar solutions]. / Printsipy optimizatsii i masshtabirovaniia nekotorykh protsessov v tekhnologii vaktsinnykh proizvodstv. Soobshchenie 3. Metodika opredeleniia optimal'nogo rezhima termicheskoi sterilizatsii rastvorov sakharov.

One of the most widespread methods of thermal sugar sterilization is the use of saturated water vapour under pressure in the capacity of heat source. Guaranteed sterility of solutions should be reached under conditions providing the least sugar splitting. However, in practice the integral effect of the thermal field on the solution is as a rule not taken into consideration. A new calculation method permitting to determine the amount of sugar split in the varying thermal field.

[Principles for optimizing and guaging several processes in the technology of vaccine production. II. Modeling processes of thermal inactivation of microorganisms]. / Printsipy optimizatsii i masshtabirovaniia nekotorykh protsessov v tekhnologii vaktsinnykh proizvodstv. Soobshchenie II. Modelirovanie protsessov termicheskoi inaktivatsii mikroorganizmov.

The paper treats of some problems pertinent to modelling of thermal inactivation of the microbes serving as a theoretical foundation for the achievement of guaranteed sterility of the equipment, communications and fluids. The principal attention is devoted to the problems of quantitative assessment of the efficacy of the mentioned processes. The advantages and the drawbacks of some deterministic and probability models which found application in microbiological laboratories are assessed. The expediency of orientation on a model proposing the use of characteristics of thermal resistance of the microorganisms and considering the heterogeneity of the actual populations by the thermoresistance index was demonstrated.

[Principles for optimizing and guaging several processes in the technology of vaccine production. I. Several problems in guaging and optimizing thermal sterilization of fluids]. / Printsipy optimizatsii i masshtabirovaniia nekotorykh protsessov v tekhnologii vaktsinnykh proizvodstv. Soobshchenie I. Nekotorye voprosy masshtabirovaniia i optimizatsii pre termicheskoi sterilizatsii zhidkostei.

Thermal sterilization of fluids--one of the widespread operations in microbiological laboratories and in vaccine production--solves two tasks: provides sterility and maximal preservation of biological value of the sterilized fluid. A possibility and expediency of using some indices for the quantitative assessment of the efficacy of the sterilization regimens, including measurement of the sterilization processes is considered in this work. A possible way of the regimen optimization on the basis of known values of the activation energies of the processes of decomposition of thermolabile components and inactivation of foreign microbial flora is assessed.