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Introduction. Minimally invasive procedures used in the treatment of children with Hirschsprung’s disease (HD) have reduced the rate of complications and allowed to perform these surgeries at any age. In literature, one can find much information on surgical treatment, complications, long-term results. However, features of postoperative period and mechanisms of colon function restorations after different pull-through procedures are not well described. Material and methods. From 2008 to 2019, 77 patients with different forms of HD were operated in Children’s Clinical Specialized Center of High Medical Technologies in St-Petersburg. Patients were aged from 14 days till 3 years. They were divided into 3 groups according to the applied endorectal technique- Soave, «Soavson», Swenson. The following parameters were analyzed: age, sex, stoma, surgery duration, length of hospitalization, features of postoperative period, complications.Results. An early postoperative period was similar in all groups. Two children after Soave procedure (9%) had wound infection; two children had anastomotic stricture (1 – Soave, 1 - «Soavson») which was treated with regular dilatations. Enterocolitis was diagnosed in 19 patients (25%). 20 patients (26%) had no self-defecation for 14 days – 6 months after the surgery. Most of the patients had HD of the rectosigmoid form. These disorders developed more often in patients after Soave and «Soavson» procedures, less often- after Svenson one.Discussion. An issue of choosing an optimal technique for rectal dissection is still a debatable one. There has been no any significant difference revealed between the three variants of endorectal dissection during an early postoperative period.Conclusion. A transanal endorectal pull-through procedure in children with HD is a preferable option of choice. It gives good functional outcomes. Features of the postoperative period are caused by the adaptation of new intestine to new defecation conditions.

Background. The cystic form of biliary atresia is a rare form of atresia of the biliary tract, which is a relatively favorable variant of the defect and can be diagnosed antenatally. In practice, it is important not only to suspect this diagnosis, but also to differentiate this variant of impaired development of the external bile duct from the cyst of the common bile duct. This is due to the difference in approaches and methods of surgical treatment of choledochal cysts and biliary atresia. Obliteration (atresia) of the bile ducts in the absence of timely surgical intervention quickly leads to the progression of cirrhosis and the development of liver failure. The method of choice in the treatment of AD is Kasai surgery, often palliative in nature, but allowing to delay the time until liver transplantation. The cyst of the common bile duct rarely requires early surgical treatment, and the risk of cirrhosis is significantly lower. Surgical intervention is aimed at removing the cyst and restoring the flow of bile by anastomosing the external bile ducts with the intestines, which is a radical method of treatment and leads to the recovery of the child. External similarity in ultrasound examination of the fetus and newborn baby of the cystic form of biliary atresia of the bile ducts with a cyst of the common bile duct does not always allow differentiation of one defect from another, which can lead to untimely correction of the defect and an unfavorable outcome. Aim. Demonstrate a rare type of biliary atresia. Materials and methods. Between 2001 and 2019, 33 patients with biliary atresia were treated in the Childrens City Multidisciplinary Clinical Specialized Center for High Medical Technologies in St. Petersburg, only two patients had a cystic form. Both children were initially treated as patients with bile duct cyst. Children were operated on at the age of 2 and 3.5 months. The first patient underwent surgery Kasai, the second hepaticoyunoanastomosis. Results. During the observation period (9 years and 4 years), the synthetic function of the liver is normal, and there are currently no indications for transplantation. Conclusion. If a fetus or a newborn with neonatal jaundice is detected during ultrasound examination of a cystic formation in the gates of the liver, it is very important to correctly and quickly make a differential diagnosis between the cystic form of biliary atresia of the biliary tract and the common bile duct cyst.

Introduction. Cysts of the common bile duct or choledoch cysts (CC) are congenital cystic dilatation of the extrahepatic and / or intrahepatic bile ducts. The etiology is not fully clear, but it has been proven that abnormal pancreatobiliary anastomosis plays a major role in CC formation. Clinical manifestations range from prolonged jaundice in newborns to non-specific abdominal pains in older patients. Purpose. To study clinical manifestations of common bile duct cysts in children of different age, to define diagnostic criteria as well as to analyze outcomes after surgical treatment. Material and methods. In 2001-2019, 27 patients with chronic obstructive CC, aged from several days to 12 y.o., were treated in the Children’s City Multidisciplinary Clinical Specialized Center for High Medical Technologies of St. Petersburg. Most of them (16-59.2%) had CC of type IA by the Todani classification. Ultrasound examination and MRI cholangiography were used for diagnostics. Children with CC of type V (Caroli disease) required a specific approach to their treatment because of the combined malformations in kidneys (polycystic kidney disease); in 19 patients with CC of types I and IV the cystically altered choledoch was resected and hepaticojejunostomy was put on the loop by the P technique. Results. 19 patients were operated on. Good outcomes were in 15 cases. Underlying disease complications in the preoperative period were noted in 8 patients: pancreatitis in 5 patients, perforation of cysts with biliary peritonitis in 3 patients. In the postoperative period, 4 patients had complications: stenosis of the anastomosis in 1; portal hypertension in 1; 3 children developed cholangitis, 1 of them required surgical correction. Out of 5 patients with Caroli disease, 2 children died in the neonatal period, one because his parents refused of treatment. Two children aged 12 and 17 had liver and kidney transplantation. Conclusion. CC clinical manifestations are diverse; asymptomatic course can develop up to some age. Ultrasound and MRI cholangiography are main diagnostic tools. Resection of the cyst with hepaticojejunostomy on the loop by the P technique is a radical approach to the treatment and has good outcomes. Patients with Caroli disease require an individual approach.

Hirschsprungs disease usually manifests from the first days of life and is diagnosed in the newborn period. In some patients Hirschsprungs disease cant be diagnosed in the newborn period because of different forms of disease and clinical features. From 2008 to 2019 75 patients with Hirschsprungs disease were operated in the City Childrens Hospital No. 1. 21 patients had delayed diagnosis. 11 newborns didnt have very clear clinical symptoms, intestinal obstruction disappeared after decompression. 2 patients with associated chromosomal disorders were diagnosed with Hirschsprungs disease later because of. In some of older patients disease manifested with severe constipations. Also, we presented some clinical cases of major diagnostic errors in patients with Hirschsprungs disease. Conclusion. Diagnostic errors in patients with Hirschsprungs disease are associated with the lack of alertness of neonatologists and inadequate interpretation of clinical manifestations and X-ray study. For many years these children can be treated by different specialists before having surgical consult.

BACKGROUND Patients requiring intensive upper airway reconstruction are anatomically restricted in terms of the respiratory support they can receive. While intraoperative extracorporeal membrane oxygenation (ECMO) has been effectively utilized, little has been shown regarding the utility of ECMO for long-term support in these patients. METHODS We demonstrate how a patient with tongue and hypopharyngeal squamous cell carcinoma that necessitated upper airway reconstruction was supported with veno-venous (VV) ECMO due to postoperative respiratory failure and an inability to maintain a stable airway. RESULTS By initiating VV ECMO, we were able to decrease positive pressure ventilation and FiO2 , thereby minimizing ventilator-associated trauma and irritation to facilitate wound healing. Over time, ventilatory support was increased in parallel with decreasing ECMO support, allowing discharge to rehabilitation after 74 days of ECMO. CONCLUSION ECMO can effectively support patients with ongoing respiratory requirements following upper airway reconstruction when standard ventilatory techniques are inadequate or not feasible.

Purpose Myocardial recovery after left ventricular device (LVAD) implantation is important to identify; however, identifying predictors of successful LVAD decommissioning, and recurrence of heart failure remains a challenge. Methods We performed a retrospective analysis on individuals who underwent a protocolized echocardiographic and invasive hemodynamic turn-down study. Patients were selected based on normalized hemodynamics, clinical stability and LVEDD Results A total of 12 patients underwent the LVAD weaning protocol. Of those patients, 42% (5/12) underwent LVAD decommissioning with sustained recovery (SR) (median 13 months) while 58% (7/12) failed recovery (FR) by requiring LVAD re-implantation after decommissioning or failed turn-down study precluding LVAD decommission. In FR versus SR patients LV-end systolic (LVESD) and -end diastolic (LVEDD) diameter were higher at the start (LVESD 4.8 ± 0.4 FR vs 3.5 ± 0.3 SR, p Conclusion In our cohort of LVAD turn-down studies, we were able to identify echo parameters, invasive hemodynamics, and LVAD pump parameters that differed between patients with failed and sustained recovery.

Purpose The intravascular ventricular assist system (iVAS) is a durable, ambulatory counterpulsation device that is currently under investigation for advanced heart failure patients. Baseline cardiac power efficiency (CPE) has previously been reported to predict hemodynamic success after iVAS. We investigated the role of change in CPE after inotropic challenge, a marker of cardiac reserve, as a prognostic tool prior to iVAS support. Methods Hemodynamic data at the time of right heart catheterization was collected on patients just prior to iVAS implantation. A subset of patients underwent milrinone loading followed by repeat hemodynamic assessment 10 min after a 50 mcg/kg milrinone infusion. Cardiac power index (CPI) was calculated as [CPI = cardiac index (CI) x mean arterial pressure (MAP)/451)] and CPE was calculated as [CPE = CPI/Pulmonary capillary wedge pressure (PCWP)]. CPE at baseline and after inotropic challenge was calculated and a percent augmentation of 25% or greater in CPE was used as a cutoff indicative of cardiac reserve. The combined endpoint of independently adjudicated heart failure events, dependency on inotropes 7 days after implant, need for escalation to ECMO or death was evaluated. Results 40 patients from a single institution underwent iVAS implantation. 39 patients underwent RHC prior to iVAS (11.7 +/- 14.0 days before surgery). 11 patients underwent milrinone loading followed by repeat hemodynamic assessment. Baseline hemodynamics revealed an average CPE of 0.0227 +/- 0.0148 watts*mmHg/m2 for the entire cohort. In the subset of patients who underwent milrinone loading, CPE increased on average 41% from 0.0141 +/- 0.0055 watts*mmHg/m2 to 0.0236 +/- 0.0114 watts*mmHg/m2 (p = 0.003). There was a trend towards freedom from death, ECMO, HF events, or inotrope dependency in those who were able to augment CPE by more than 25% (N = 8), compared to those with less (N = 3) cardiac reserve OR = 0.071 (95% CI 0.003 - 1.73, p = 0.105). Conclusion Cardiac reserve as defined as a greater than 25% augmentation in CPE after milrinone challenge may predict future success with counterpulsation with iVAS. This hypothesis generating question warrants further investigation.

Purpose Tolvaptan, a selective vasopressin type-2 antagonist, has been shown to increase serum sodium (Na) and urine output in hyponatremic left ventricular assist device (LVAD) patients in retrospective studies. We aimed to assess the efficacy of tolvaptan in this population in a prospective, randomized study. Methods We conducted a prospective, randomized, non-blinded study of LVAD recipients with post-operative hyponatremia (Na Results A total of 33 patients were consented, 30 of whom developed post-operative hyponatremia. Two were excluded due to new onset renal failure requiring hemodialysis prior to development of hyponatremia. Of 28 eligible patients (21% women, 54% Black, 32% ischemic cardiomyopathy) 15 were randomized to tolvaptan (TLV), and 13 were randomized to standard care alone (No-TLV). Patients in TLV had a significant increase in Na from randomization to discharge, 133 (IQR 132-134) to 135 mEq/L (IQR 134-137), p=0.018, while those in No-TLV did not have a significant change in Na, 133 (IQR 132-134) to 134 mEq/L (IQR 132-136), p=0.15 (1A). There were no significant differences in renal function in either arm of the study: eGFR 76 (IQR 51-99) to 80 mL/min/1.73m2 (IQR 66-90), p=0.97 in TLV versus eGFR 78 (IQR 56-115) to 115 mL/min/1.73m2 (IQR 56-120), p=0.13 in No-TLV (1B). Patients in TLV had significantly more urine output than those in No-TLV during their first 24 hours of hyponatremia (3294 vs 2155 mL, p=0.043) and during last 24 hours of hyponatremia prior to sodium correction (4177 vs 2739 mL, p Conclusion Tolvaptan improves Na in hyponatremic post-operative LVAD patients when compared to those not receiving tolvaptan without adversely impacting renal function.

This study presents health statistics for a specialized trauma department in a large pediatric hospital in St. Petersburg. Data relating to patients treated in the trauma department for any injuries and with injuries of the musculoskeletal system were analyzed separately. Injuries of the musculoskeletal system, accounted for 67.3% of all children hospitalized in the trauma department. We also identified patients with injuries of the musculoskeletal system who were treated in non-specialized departments of the hospital (accounting for 4.1% of patients in these departments). Detailed characteristics of the pediatric trauma departments, the characteristics of children hospitalized with injuries of the musculoskeletal system, methods for diagnosis, treatment, and rehabilitation are described. The challenges of rehabilitation for children with injuries and the need to increase the hospital capacity are also described.

Background The novel SARS-CoV-2 virus causing COVID-19 has been associated with diverse cardiovascular pathology. We present a case of cardiomyopathy due to possible COVID-19 resulting in cardiogenic shock. Case A 54 year-old male presented to the hospital with 4 weeks of progressive dyspnea, leg swelling, and weight gain. His symptoms began 4 weeks after experiencing influenza-like symptoms after a trip to China during the height of their COVID-19 outbreak. He was admitted to the COVID unit in cardiogenic shock and was later intubated for acute hypoxic respiratory failure. Laboratory data demonstrated acute kidney injury, elevated transaminases, lactic acidosis, elevated pro-BNP N-Terminal to 3932pg/mL, and high sensitivity troponin to 72ng/L. Transthoracic echocardiogram showed severe biventricular failure with a LVEF of 10% and a LVIDd 5.2cm. SARS-CoV-2 RNA was negative twice, but SARS-CoV-2 IgG AB and SARS-CoV-2 IgA AB were positive. Urgent right and left heart catheterization was performed demonstrating non-obstructive coronary artery disease and hemodynamics consistent with cardiogenic shock. While supported with an intra-aortic balloon pump (IABP) and norepinephrine, he had a fick cardiac output 3.1 L/min, fick cardiac index 1.6 L/min/m2, pulmonary capillary wedge pressure 37mmHg, right atrial pressure 25mmHg, and pulmonary arterial pressures 65/40mmHg. Given persistent cardiogenic shock on IABP and inotropes, he was later transitioned to Veno-Arterial Extracorporeal Membrane Oxygenation (VA ECMO) and an Impella CP for left ventricular unloading. He continued to have persistent INTERMACS I shock and underwent successful implantation of a HeartMate 3 LVAD with percutaneous temporary right ventricular assist device (RVAD). Pathology of the left ventricular apical core demonstrates polyclonal endocardial infiltration of B-Cells, CD4 and CD8 positive T-Cells, eosinophils, macrophages, and plump reactive endothelial cells (Figure 1). He is currently recovering in the ICU off of vasoactive support with subsequent removal of percutaneous RVAD. Conclusion This is a suspected case of COVID-19 associated cardiomyopathy presenting as new on-set heart failure with reduced ejection fraction complicated by cardiogenic shock. There is still much to learn about the cardiac manifestations of COVID-19 and further studies are needed to determine appropriate diagnostics and management of such cases.

Purpose Driveline infections in patients with left ventricular assist devices (LVAD) have long been an adverse event that has been difficult to eliminate. Driveline infections lead to an increased morbidity and mortality and a decrease in quality of life for patients. This review served to determine if using antibiotics as prophylactic therapy can affect infection rates and increase survival in patients who have had trauma or manipulation of the driveline. Trauma or manipulation can consist of a controller drop, driveline tug. Methods A retrospective chart review was done at a large academic medical center. We reviewed all patients implanted with an LVAD within the past 5 years. Patients were divided by infection vs non-infection; patients were then evaluated by who was treated with prophylactic antibiotic therapy and who developed an infection post antibiotic therapy compared to patients that developed an infection with no prophylactic therapy. We then reviewed survival rates within that cohort of patients. Results A total of 258 patients were evaluated for driveline infection. Of those, 73 (28%) patients had developed a driveline infection. Of those 73, 62 (84%) were not treated with prophylactic antibiotic therapy and 11 (15%) received prophylactic antibiotics. Mortality within the group of patients with no prophylaxis therapy was 25 (40%) vs 1 (9%) p=0.03 in the patients that were treated with prophylaxis antibiotic therapy. Conclusion Prophylactic antibiotic therapy can be useful to prevent driveline infections and increase survival in patients with a known controller drop or driveline tug. Further studies should be done to evaluate further prophylactic antibiotic therapy in other cohorts of patients.

Purpose It is well-documented that tobacco smoking has significant cardiovascular ramifications. However, the effects of tobacco smoking upon Ventricular Assist Device (VAD) implant outcomes are understudied. We aimed to ascertain the effort that institutions devote to smoking cessation programs for VAD patients and the success of these programs. Methods Using Survey Monkey®, a 13-question survey was created and distributed to 26 VAD institutions. Examples of multiple-choice questions included: 1) the volume of VAD patients at the respondent's center, 2) the patient population with active or past use of tobacco, 3) the presence and breadth of smoking cessation programs, and 4) the respondents’ views on program success. Results Respondents (n=15, 58%) stated that more male patients (n=12,75%) were smokers at the time of implantation. The most prevalent ages of tobacco smoking among patients were nearly evenly distributed between the ages of 35-70, but one institution reported the most common age as below 35 years. While pre-implant smoking cessation was not required at most programs (n=13, 87%), nearly all (n=14, 93%) offered cessation therapy after implant, with half of the respondents viewing the programs as effective. There was no apparent correlation between feelings of effectiveness and the category of tobacco smoking cessation therapy (Figure 1). Several respondents indicated that tobacco smoking cessation programs are not effective in Destination Therapy patients, while Bridge-to-Candidacy offers an incentive for compliance. Conclusion Although tobacco smoking is not a contraindication for device implantation, our data suggests programs are dedicated to utilizing smoking cessation strategies for patients. However, no definitive strategy was identified in successful tobacco smoking cessation programs in our study, pointing to the need for research. Additionally, studies of standards, protocols, and team involvement are areas that could provide data to improve the outcomes of tobacco smoking cessation among VAD patients.

Purpose International shared care can provide access to advanced options for patients in various parts of the world with end stage heart failure who are deemed high risk surgical candidates. We sought to describe the process utilized to provide successful, co-managed, culturally sensitive international shared care. Methods A retrospective analysis was performed to evaluate outcomes and hemocompatability related adverse event (HRAE) rates of a successful international shared care model between a large, academic medical center in the United States (US) and two shared care hospitals located in two countries in the Middle East. Results After training at the implant site is completed by the shared care team, a partnership can continue remotely. Ongoing communication with the International office ensures a streamlined process for referrals, successful transition for a patient to return home, co-management of adverse events, and continued education for patients, families, and shared care providers. This partnership resulted in 109 patient referrals since 2016. 7 patients were discharged from the hospital on centrifugal flow ventricular assist devices (HM3 n=3 or HVAD n=4) with 100% survival at 6 months and 85% of patients returned home (n=6). Since discharge, there has been 100% freedom from stroke or thrombosis related adverse events compared to IMACs 69.1% at 6 months for patients on isolated centrifugal flow device. Additional adverse events include 1 driveline infection (14%) and 1 outpatient GI bleed (14%). Conclusion International shared care provides access to advanced heart failure therapies in other countries and co-management facilitates improved patient outcomes with lower HRAE rates. Quality VAD care can be shared, regardless of language or location. Further application of this model in other countries should be further employed and evaluated.

Purpose Left Ventricular Assist Devices (LVAD) is a growing form of therapy for patients with advanced heart failure. While LVAD patient volumes grow, the need for additional education both for the patients and hospitals has grown. The implementation of dedicated LVAD educators into LVAD programs can be beneficial for program quality indicators as well as patient outcomes. Methods Retrospective chart review at a large academic University, comparing median length of stay, driveline infection rates, unplanned readmission's, and one year survival from between 2017 and 2018 when a dedicated LVAD educator was implemented into the program. Results The implementation of a dedicated LVAD educator occurred January of 2018. Outcome results were evaluated for 2017 prior to the educator and 2018 after implantation of the educator. The volumes for 2017 and 2018 were similar at 47 and 63 respectively. Outcomes evaluated included median length of stay from implant of LVAD to discharge from hospital which decreased from 20.5 days to 18.9 days. Driveline infections rates decreased from 23.81% to 17.71%. Unplanned readmission's decreased from 3.53% to 2.91% and one year survival between the two groups remained comparable at 93.74% and 92.81%. Acuity of the patients was comparable in both groups and programmatic staffing remained unchanged otherwise. Conclusion Incorporating a dedicated LVAD educator into LVAD programs proves to be beneficial by decreasing length of stay, decrease driveline infection rates, decrease unplanned readmission while maintaining overall one year survival.

Purpose Left ventricular assist device (LVAD) implantation for patients refusing blood transfusion presents a distinct challenge. This study summarizes our center's experience in clinical outcomes of LVAD implantation for patients who refuse blood transfusion. Methods The cohort included 21 Jehovah's Witness (JW) patients who underwent an LVAD implantation between 2008-2019. Non-JW patients (N=427) served as a control. We previously established the perioperative optimization protocol for JW patients. The protocol includes preoperative optimization of hemoglobin (Hb) level with a goal of >12 g/dl using iron, vitamin B12, and erythropoietin. There are also protocolized intraoperative techniques and postoperative management to minimize blood loss. Results Hb levels in eight patients (38.1%) were successfully optimized (as defined by Hb>12g/dl) before surgery in the JW group. In-hospital mortality was 14.3% (3/21) in the JW group, and 11.7% (50/427) in the non- JW group (p=0.35). One-year survival was similar between in the JW group and the non- JW group (79.3±9.3% vs. 68.1±2.4%, p=0.43). Causes of mortality during the follow-up period in the JW group included stroke (N=4), right-sided heart failure (N=2), device thrombosis, sepsis, gastrointestinal bleeding (GIB), and unknown (N=1), respectively. Freedom from GIB at 1 year was 83.9± 8.5% in the JW group and 74.9±2.4% in the non-JW group (Log-Rank p=0.95). Overall, 5 patients suffered from GIB during follow up in the JW group. Three of them required esophagogastroduodenoscopy or endovascular catheterization to obtain hemostasis with medical therapy including intravenous iron, erythropoietin, and octreotide. Conclusion The clinical outcomes of LVAD implantation for patients refusing blood transfusion were comparable to those who accepted blood transfusions. LVAD therapy for such a patient population is feasible in select patients and is facilitated with the use of perioperative optimization protocols.

An analysis of treatment results was made in 216 patients with intussusception of bowels at the period from 2000 to 2015. The authors showed that it would be reasonable to carry out a conservative therapy in the cases of recurrent intussusception in absence of peritonitis symptoms.

An analysis of treatment results was made in 216 patients with intussusception of bowels at the period from 2000 to 2015. The authors showed that it would be reasonable to carry out a conservative therapy in the cases of recurrent intussusception in absence of peritonitis symptoms.

Purpose Durable Left Ventricular Assist Devices (LVAD) are typically implanted with an inflow cannula in the LV apex and an outflow graft anastomosed to the aorta. We describe 4 pts who experienced clinically significant outflow graft stenosis requiring intervention, an underreported but likely increasingly common complication in pts on long term support with a VAD. Methods A retrospective review of our VAD database was performed on pts implanted with a durable VAD at our institution from 2011-2018. Results Four pts were found to have stenosis of the outflow graft confirmed by CT angiogram (Figure). Each of the pts presented with symptoms of acute on chronic LV failure with a decrease in VAD flows, prompting the diagnostic evaluation. The pre-VAD etiology of heart failure was nonischemic cardiomyopathy for 3 pts and transposition of the great arteries with VAD implanted into the systemic ventricle in the 4thpatient. Mean time from implant to diagnosing the stenosis was 722 days. In all pts the cause of the stenosis was external compression from accumulation of fluid or hematoma between the gore-tex applied at the time of implant and the outflow graft. The stenosis was focal in three and diffuse in one pt. Two of the pts were successfully treated with stenting of the outflow graft and one pt was taken for surgical release of the gore-tex. In the 4thpt, the stenosis was an incidental finding as we diagnosed acute thrombus ingestion into the inflow cannula which resolved with thrombolytics. All pts experienced an immediate increase in >2L of VAD flow following each, respective, intervention. Conclusion Outflow graft stenosis in VADs is a serious complication that can lead to decompensated heart failure, the cause of which may be external compression related to gore-tex around the graft. This complication should be included in the differential diagnosis of a drop in VAD flows, and while treatable, should prompt a reassessment of how gore-tex is applied (if at all) at the time of implant.

The aim of the study was to reveal specificity of the anemnesis and of the immune system condition in children with primary peritinitis who had undergone a cavitory operation that failed to reveal the cause of the inflammation and to improve their health. There was some increase of the relative content of activated monocytes with the classic phenotype CD14 bright CD16 - HLA-DR + versus the total number of monocytes with a phenotype CD14 bright.

The effect of initial orientation of samples on the magnetic properties and texture of ultrathin grain-oriented steel strips produced of them has been studied. In a number of cases, the samples with a larger initial deviation from the ideal (110)[001] orientation demonstrate a higher level of magnetic properties (if considering the total set of characteristics) in comparison with the samples with a small initial deviation. For the samples with a larger initial deviation, the final magnitudes of the magnetic induction obtained after the treatment exceed its initial magnitudes. Therefore, for producing an ultrathin grain-oriented electrical steel with high properties, a material with a scattered orientation of grains relative to the ideal (110)[001] orientation can be used.

It is shown that upon cold rolling the deformation of an Fe-3% Si-0.5% Cu single crystal with a (110)[001] orientation occurs, along with slip, by twinning in the (112) $$[\bar 1\bar 11]$$ and (11 $$\bar 2$$ ) $$[\bar 1\bar 1\bar 1]$$ . systems. Upon a reorientation of the crystal lattice due to the operation of the slip system (112) $$[\bar 1\bar 11]$$ , the twins of the (112) $$[\bar 1\bar 11]$$ type occupy a regular position in the octahedral matrix (111) $$[\bar 1\bar 12]$$ , retaining a special misorientation Σ3 with the matrix in the entire process of deformation. The twinning system (11 $$\bar 2$$ ) $$[\bar 1\bar 1\bar 1]$$ occupies an irregular position in the (111) $$[\bar 1\bar 12]$$ , matrix, but also proves to be in a special misorientation Σ3 with it. A dislocation mechanism is suggested, which makes it possible to explain the retention of the special misorientation and the inclination of the habit plane of twins of both systems of twins.

The article investigates the twinning evolution of two active systems during cold rolling of a (110)[001]-oriented Fe3 pct Si single crystal. An intriguing fact is revealed that for both twinning systems the Σ3 misorientation is retained, regardless of the fundamental difference in their transformation in the course of the matrix crystal lattice reorientation. One of the twinning systems retains the regular habit plane position, while the other acquires an irregular one. A model is proposed that describes the mechanism of such transformations.

A model of the formation of shear bands upon cold deformation of {111}〈112〉 crystals of a commercial Fe-3%Si alloy is proposed. The model suggests a two-stage mechanism for the formation of a shear band and its fine structure. At the first stage, there occurs an anomalous twinning in the {114}〈221〉 system; at the second stage, an almost complete secondary twinning of the band in two standard {112}〈111〉 systems occurs. As a result of these transformations, the shear band consists of regions with an almost cube-on-edge orientation {11 11 1}〈1 1 22〉 and an “octahedral” {111}〈112〉 orientation, which is symmetrical with respect to the initial {111}〈112〉 orientation. A crystallographic mechanism responsible for an anomalous twinning in the {114}〈221〉 system by the slip of (8a/18)〈221〉 partial dislocations is proposed. It is supposed that the shear bands observed consist of groups of different numbers of shear microbands.

Cold rolling is an important means of obtaining industrially useful metals and alloys with a bcc lattice (lowcarbon steel sheet, transformer steel, molybde� num alloys, β alloys of titanium, etc.) and largely determines the dimensions and properties of the prod� ucts. Considerable experimental and theoretical infor� mation is now available regarding the reorientation of the crystal lattice in different materials, under differ� ent loading conditions (1-10). Lattice reorientation under the action of several slip systems may be described as follows, according to (5, 8)

An immunological research of the patients and control group with primary peritonitis was made. The main indices of immune response were in the range of age rates. However, the immune signs of foci of chronic inflammation were revealed in patients after operation. The consequences of disease (an abdominal cavity effusion) were eliminated during surgical interventions, but not the cause of the inflammation. Children with the primary peritonitis should be examined for detection of infection foci.