The duplex kidney assosiated with obstructive uropathy of the upper and lower segments is a condition difficult to manage in pediatric urology. Embryological predisposition determines a number of significant functional and urodynamic disorders that are common in children at the age of 3 years. That decrease the quality of children’s lives, especially under 3 years old. The article presents a clinical case of a 3-month girl. The 20-week antenatal ultrasound scan showed a duplication of the right kidney with megaureter of both segments without critical dilation. The leukocyturia was detected after birth. The child was admitted to the surgical hospital. Nephrostomy tubes were inserted in the duplex kidney due to severe purulent pyelonephritis. The girl was diagnosed with hydronephrosis of the lower segment with a decreased function by 52%, non-refluxing megaureter of the upper segment with absence of upper half kidney function. Pyeloplastic of the lower half of the ureter was performed. Epigeminefroureterectomy of the upper half of the kidney was performed at 6 months. In conclusion, duplex kidney assosiated with obstructive uropathy requires timely diagnosis and patient follow-up.

BM@N (Baryonic Matter at Nuclotron) is the first experiment operating and taking data at the Nuclotron/NICA ion-accelerating complex.The aim of the BM@N experiment is to study interactions of relativistic heavy-ion beams with fixed targets. We present a technical description of the BM@N spectrometer including all its subsystems.

The paper describes the professional activities and merits of the pediatric surgeon Olga G. Mokrushina in celebration of her anniversary.

BACKGROUND: Anorectal abnormalities occur in 1:1,500 to 1:5,000 live births. There is still no agreement on the best surgical procedure for treating some types of anorectal abnormalities in males. Anorectoplasty could be performed using the posterior sagittal approach and using laparoscopic techniques. AIM: To assess the risk of postoperative complications and determine their specificity in males with anorectal malformations, depending on the surgery approach. MATERIALS AND METHODS: A single-center retrospective cohort study was performed. Male patients with anorectal malformations who had surgical correction of anorectal malformation by posterior sagittal (group I) or laparoscopic-assisted anorectoplasty (group II) at the age of up to 1 yr at the N.F. Filatov Childrens City Clinical Hospital from 2008 to 2022. Postoperative and intraoperative problems and the number of surgical interventions that had to be redone to correct issues were noted. RESULTS: Of the 33 patients in group I, 18 (55%) had anorectal malformations with bulbar fistula, 12 (36%) had anorectal malformations without fistula, and three (9%) had a prostatic fistula. Group II included 99 patients, with 53 (54%) having anorectal malformations with prostatic fistula, 30 (30%) having anorectal malformations with bulbar fistula, nine (9%) having anorectal malformations with bladder neck fistula, and seven (7%) having anorectal malformations without a fistula. The incidence of intraoperative and postoperative complications was statistically significantly higher in children after posterior sagittal anorectoplasty than laparoscopic-assisted anorectoplasty: I, 19 (58%) versus II, 33 (33%); p = 0.014. The number of redo surgical interventions to correct complications did not differ significantly between the studied groups: I, 8 (24%) versus II, 26 (26%); p = 0.819. The incidence of urethral damage was identified with posterior sagittal anorectoplasty compared with laparoscopic-assisted anorectoplasty: I, 4 (12%) versus II, 0 (0%); p 0.001. We found no differences in postoperative complications between laparoscopic-assisted and posterior sagittal anorectoplasty. CONCLUSIONS: The results define laparoscopic-assisted anorectoplasty as a viable and promising method that does not have specific postoperative complications if it is technically correctly performed. It is necessary to develop clear criteria for rectum mobilization and the volume of rectourethral fistula dissection during laparoscopic-assisted surgery to reduce the risks of postoperative problems and repeat surgery.

Introduction. The open Ladd surgery is a standard treatment of intestinal malrotation. After implementing laparoscopic techniques into clinical practice, the number of reports on successful treatment of this defect with minimally invasive laparoscopic techniques is growing. However, publications on such correction of the defect in newborns are rather scarce.Purpose. To improve management of newborns with intestinal malrotation.Material and methods. Retrospective and prospective analyses of 77 newborns with intestinal malrotation, treated in 2002–2020, have been made. The studied group included 35 newborns; the control group – 42. StatTech program was used for statistical data processing.Results. Groups were comparable in anthropometric indicators, gender composition, gestational age. The following differences were revealed during the study: laparoscopic surgery lasts longer than the open surgery. The intensive care period was uneventful in the studied group. Passage through the intestine was restored faster, enteral feeding started earlier in the laparoscopic group too. The number of bed days in patients operated with minimally invasive techniques was less , if to compare to the control group with open surgery. After the open surgery, children often required intestinal stimulation in order to restore passage through the gastrointestinal tract. The incidence of complications does not depend on the applied surgical technique. Relapses in both groups are comparable; the leading factor in developing relapses is violations of surgical techniques.

Introduction. An acquired recto-perineal fistula in childhood is a quite rare pathology. One of its main causes is trauma of the perineal part of the rectum and anal canal. That is why, acquired rectoperineal fistulas most often develop after the correction of Hirschsprung’s disease and anorectal malformations. Material and methods. The publication presents a rare case of a newborn child with recurrent course of an acquired rectoperineal fistula which developed after sacrococcygeal teratoma treatment. The teratoma was removed when the child was 3 days old. The surgery was complicated with suture dehiscence in the rectal wall defect. After suturing, a separate sigmostoma was placed. At the age of 6 months, the sigmostoma was closed, but after a few days, fistulas were found in the area of drainage and postoperative scar, which required sigmostoma restoration. After the prescribed therapy, the fistulas were obliterated; the stoma was closed again. In 2 weeks, child’s general condition deteriorated, and newly appeared fistulas were noted. It was decided to perform demucosation of the disconnected rectum above the level of anal sphincter and to make fistula through drainage via the rectum lumen. Conclusion. Acquired recto-perineal fistulas in childhood is a rare recurrent disease. Though postoperative complications were detected in time, authors could not get independent closure of the fistula, despite numerous interventions. In fact, only the rectum extirpation allowed to separate the fistulous tract from the intestinal lumen. This type of intervention is considered a quite rare one; usually, such complication can be eliminated in a less radical way.

Background . Ureterocele is a cystic dilatation of the distal ureter. Orthotopic ureterocele is relatively rare form of this disease, and it is commonly diagnosed in female children. The clinical picture of orthotopic ureterocele is usually not significant, and the management variants are unclear. Clinical case description. Ultrasound has revealed dilatation in the distal part of the left ureter (up to 6.5 mm) and cyst formation (diameter of 8 mm, thick walls) in the bladder in 8-months-old boy. The retrograde voiding cystourethrogram has shown no signs of vesicoureteral reflux. The evaluation of the voiding rhythm was performed: the volume of residual urine was > 30%, it indicates the infravesical obstruction. The child underwent diagnostic cystourethroscopy, transurethral resection of the ureterocele, intubation ureteral catheter in the left ureter (all procedures was performed under general anesthesia). There were no enlargements of calices-pelvis system and ureters 12 months after surgery according to urinary system ultrasound. Clinical urine test with no inflammatory changes. Voiding rhythm was without pathology. Conclusion . The widespread implementation of high-tech and minimally invasive methods of diagnosis and management allow us to achieve timely detection and provide effective treatment for children with ureterocele.

First physics results of the BM@N experiment at the Nuclotron/NICA complex are presented on π+ and K+ meson production in interactions of an argon beam with fixed targets of C, Al, Cu, Sn and Pb at 3.2 A GeV. Transverse momentum distributions, rapidity spectra and multiplicities of π+ and K+ mesons are measured. The results are compared with predictions of theoretical models and with other measurements at lower energies.

BACKGROUND: Congenital stenosis of the ureterоpelvic junction is the most common cause of hydronephrosis in children. AIM: This systematic review aimed to search and analyze modern literature from 1998 to 2021 on the treatment and postoperative follow-up of children with severe hydronephrosis in the first year of life and study the long-term results. MATERIALS AND METHODS: Literary sources were searched in PubMed, Web of Science, Scopus, Google Scholar, and eLibrary databases. The following keywords were used to search for English sources: congenital hydronephrosis, severe hydronephrosis, operative treatment, uretero-pelvic junction obstruction infant, children, neonatal, and infancy. Five full-text articles that meet the criteria were included for analysis. RESULTS: A total of 355 patients were included in the publications. Antenatal screening was described only in two studies. The average age of children at the time of surgery was five months (one to six months). All the authors noted that due to pyeloplasty in the first year of life, the renal parenchyma exhibited a significant increase in thickness; the indicators in dynamics increased by an average of 1.5 times during the year. The size of the renal pelvis decreased by 50%67%. The data of radioisotope scintigraphy were variable; however, in the long-term period, improvement in renal function was noted in all publications. CONCLUSIONS: This systematic review shows the long-term results of early pyeloplasty in congenital hydronephrosis in young children. A significant decrease in the pelvis and an increase in the thickness of the parenchyma were observed, both of which are an advantage for the restoration of renal function. However, no single algorithm can predict the recovery of renal parenchyma. An accurate assessment of renal parenchymal function should be confirmed by a prospective, randomized, long-term, follow-up study with a large number of cases.

An abscess of the round ligament of the liver in children, as a result of an inflammatory process, often leading to necrosis, is an extremely rare occurrence. Formations in the round ligament of the liver must be differentiated from liver tumors, which can be diagnosed using instrumental research methods. In the available literature on the abscess of the round ligament of the liver, the authors speak about the preference for complete excision of the ligament. However, analyzing the experience (5 clinical examples are given) of the surgical clinic of the N. F. Filatov Children’s City Clinical Hospital (Moscow, Russia), the most preferable and safe are puncture and drainage of the abscess cavity from the anterior abdominal wall under visual control of manipulation using a laparoscope.

The NUCLEON space observatory was developed to measure the spectra of cosmic ray nuclei with individual charge resolution in the energy range of several TeV to 1 PeV per particle. The NUCLEON was launched into a heliosynchronous orbit as an additional load on the Resurs-2P production satellite on December 28, 2014, and it is still in operation (2019). This work is a brief review of the results from the NUCLEON observatory over three years of operation in orbit. The spectra of the main primary abundant nuclei and product nuclei of cosmic rays (CRs) are presented. Some new interesting features of the CR spectra found in the NUCLEON data are discussed.

The results of the prototype development of a data concentrator application-specific integrated circuit (ASIC) for the time-projection chamber of the MPD experiment (NICA, Dubna) are presented. ASIC is designed to serialize data coming from two SAMPA detector chips and transmit them via AWG 36 type electrical cables of up to 1 m length at 2.56 Gbit/s transmission rate to the data acquisition controller board. The article describes the structure, main characteristics and layout of the ASIC, as well as the protocol of data exchange with the external controller. A description is given of the design methods used to ensure the radiation tolerance of ASIC to the effects of high-energy particles. The prototypes are manufactured using 65 nm CMOS process from TSMC and embedded in CPGA120 package. The total power consumption of the ASIC does not exceed 500 mW.

The results of the concentration method development for the data coming from the detector integrated circuits, intended for the experimental facilities MPD and BM@N, are presented. Charged particle detectors at these installations are characterized by a high granularity and accuracy of the detecting equipment. That results in a large data volume and the need to transfer processed data at a gigabit rate. Therefore, ASIC of the data concentrator requires both a high integration and use of specific structure as well as circuit and layout to provide an increased radiation tolerance. A specific feature of the ASIC is its ability to operate in the actual radiation background of the experiments estimated by up to 100 kRad in terms of immunity to heavy charged particles. In order to approbate the method and solutions on improvement of the radiation tolerance, the design results of a prototype 65 nm CMOS ASIC for read-out the signals from two SAMPA front-end chips cards are described. ASIC is intended for data receipt, concentration and subsequent transmission at a rate of 2.56 Gbit/s over micro-coaxial cables of 1 m length.

The results of designing a readout ASIC for GEM detectors are presented. The chip has a built-in digital signal processing system intended to calculate the maximum signal amplitude (input charge) and based on the principle of interpolation. Using interpolation allowed to calculate the maximum charge amplitude with an accuracy of 1.5 LSB at using a built-in 10-bit ADC having a maximum conversion frequency of 25 MHz and a shaping amplifier with a peaking time of 320 ns. The readout ASIC was designed in UMC MMRF 180 nm CMOS process.

The design results of a charge-sensitive amplifier (CSA) with a pseudo-differential output are presented. The CSA is intended for operation with signals of both polarities at the dynamic range up to 100 fC and parasitic detector capacitances up to 100 pF. In order to form a pseudo-differential signal, a first-order low-pass filter having a cutoff frequency of several hertz was used. CSA is designed in 180 nm CMOS process.