[Ectopic acromegaly due to bronchial neuroendocrine tumors: the first description in Russia of three clinical cases].

 Acromegaly is a neuroendocrine disorder caused by excessive production of growth hormone (GH). In the majority of cases the cause of acromegaly is a pituitary tumor producing GH. Cases of ectopic acromegaly are much rarer. Ectopic acromegaly occurs in cases of tumors which produce growth hormone-releasing hormone (GHRH) or extrapituitary tumors which produce GH. The main sources of excessive GHRH production are neuroendocrine tumors (NETs) of the lung or pancreas. Treatment of ectopic acromegaly consists of surgical removal of the source of GHRH hyperproduction and in cases where surgery is not an option, somatostatin analogues, pegvisomant, chemotherapy, immunotherapy or radiation therapy are used.In this article three cases of ectopic acromegaly due to GHRH-producing lung NETs are presented, each of them being notable for a number of features. In the first two cases, clinical symptoms were mild, besides in the second case ectopic acromegaly was accompanied by primary hyperparathyroidism. In the third case ectopic acromegaly was accompanied by pituitary macroadenoma, and after surgical removal of the lung NET remission of acromegaly was not achieved. In all three cases, lung NETs were detected incidentally on radiologic chest screening for other conditions.

[Diagnostic value of bilateral inferior petrosal sinus sampling in various modifications and methods of radiation and radionuclide imaging in the diagnosis and differential diagnosis of ACTH-dependent endogenous hypercortisolism].

AIM: To analyze the diagnostic performance of bilateral inferior petrosal sinus sampling (BIPSS) with desmopressin as a stimulation agent and prolactin measurements to control catheter position with or without the ACTH/prolactin normalized ratio calculation in the differential diagnosis of ACTH-dependent endogenous hypercortisolism, and the diagnostics performance of ectopic ACTH-syndrome (EAS) visualization. MATERIALS AND METHODS: A single-center diagnostic study with a retrospective analysis of the data was carried out. The study included patients with ACTH-dependent endogenous hypercorticism with no visualization of pituitary adenoma on MRI or adenoma sizes less than 6 mm. All patients underwent BIPSS with and without calculation of the ACTH/prolactin normalized ratio. Visualization of an EAS included pituitary MRI (to exclude EAS), whole-body CT scan with contrast, and somatostatin receptor scintigraphy with 99mTc-Tectrotide and CT (99mTc-Tectrotide SPECT). The final verification was based on immunohistochemical confirmation of the tumor or stable remission of Cushing's disease (CD) after surgical treatment. Statistical data processing was carried out by using IBM SPSS Statistics 23. Confidence intervals were calculated using the JavaStat online calculator. RESULTS: 230 BIPSS were performed in 228 patients (166 women, 62 men), of which 178 patients were verified as CD and 50 cases were EAS of various localization. The effectiveness of catheterization of petrosal sinuses was 96.9%. The sensitivity of BIPSS without ACTH/prolactin ratio calculation (n=70) was 95.9% (95% CI 86.3-98.9), specificity was 92% (95% CI 75.0-97.8), for the BIPSS with additional determination of ACTH/prolactin-normalized ratio (n=51) - 97.3% (95% CI 86.2-99.5) and 93.8% (95% CI 71.7-98.9), respectively. The use of the MRI method for this sample of patients had a sensitivity of 60.2% (95% CI 52.6-67.5), specificity of 59.2% (95% CI 44.2-73.0), the total body CT with contrast has a sensitivity of 74% (95% CI 59.7-85.4), specificity of 100% (95% CI 97.95-100). The diagnostic accuracy for 99mTc-Tectrotide SPECT in NET visualization has a sensitivity of 73.3% (95% CI 44.9-92.2), specificity of 100% (95% CI 95.3-100). CONCLUSION: BIPSS with desmopressin stimulation and prolactin measurements to control catheter position, as well as the additional calculation of the ACTH/prolactin-normalized ratio, is an optimal method for the differential diagnosis of EAS. Patients who are identified an EAS on BIPSS may be further referred for 99mTc-Tectrotide SPECT and CT for tumor visualization.

[Plasma miRNA expression in patients with genetically confirmed multiple endocrine neoplasia type 1 syndrome and its phenocopies].

BACKGROUND: MEN-1 is a rare autosomal dominant disease caused by mutations in MEN1 gene encoding the menin protein. This syndrome is characterized by the occurrence of parathyroid tumors, gastroenteropancreatic neuroendocrine tumors, pituitary adenomas, as well as other endocrine and non-endocrine tumors. If a patient with the MEN-1 phenotype carry no mutations in the MEN1 gene, the condition considers a phenocopy of syndrome (phMEN1). The possible cause of this changes could be changes in epigenetic regulation, particularly in microRNA expression that might affect menin signaling pathways. AIM: to identify differently expressed circulating miRNAs in plasma in patients with genetically confirmed MEN-1 syndrome, its phenocopies and healthy controls. MATERIALS AND METHODS: single-center, case-control study was conducted. We assessed plasma microRNA expression in patients with genetically confirmed MEN-1 (gMEN1), phMEN1 and healthy controls. Morning plasma samples were collected from fasting patients and stored at -80°C. Total RNA isolation was performed using miRNeasy Mini Kit with QIAcube. The libraries were prepared by the QIAseq miRNA Library Kit following the manufacturer. Circulating miRNA sequencing was done on Illumina NextSeq 500 (Illumina). Subsequent data processing was performed using the DESeq2 bioinformatics algorithm. RESULTS: we enrolled 21 consecutive patients with gMEN1 and 11 patients with phMEN1, along with 12 gender matched controls. Median age of gMEN1 was 38,0 [34,0; 41,0]; in phMEN1 - 59,0 [51,0; 60,0]; control - 59,5 [51,5; 62,5]. The gMEN1 group differed in age (p<0.01) but not gender (р=0.739) or BMI (р=0.116) compared to phMEN1 and controls group, the last two groups did not differ by these parameters (p>0.05). 25 microRNA were differently expressed in groups gMEN1 and phMEN1 (21 upregulated microRNAs, 4 - downregulated). Comparison of samples from the phMEN-1 group and relatively healthy controls revealed 10 differently expressed microRNAs: 5 - upregulated; 5 - downregulated. In the gMEN-1 and control groups, 26 differently expressed microRNAs were found: 24 - upregulated; 2 - downregulated. The miRNAs most differing in expression among the groups were selected for further validation by RT-qPCR (in the groups of gMEN1 vs phMEN1 - miR-3613-5p, miR-335-5p, miR-32-5p, miR-425-3p, miR-25-5p, miR-576-5p, miR-215-5p, miR-30a-3p, miR-141-3p, miR-760, miR-501-3p; gMEN1 vs control - miR-1976, miR-144-5p miR-532-3p, miR-375; as well as in phMEN1 vs control - miR-944, miR-191-5p, miR-98-5p). CONCLUSION: In a pilot study, we detected microRNAs that may be expressed differently between patients with gMEN-1 and phMEN-1. The results need to be validated using different measurement method with larger sample size.

[Clinical features, diagnostics and treatment of FGF23 secreting tumors: series of 40 clinical cases].

INTRODUCTION: Tumor-induced osteomalacia is an acquired rare disease manifested by hypophosphatemic osteomalacia due to excessive secretion of fibroblast growth factor 23 (FGF23). FGF 23 is a non-classical hormone secreted by bone tissue (osteocytes) and regulates phosphorus metabolism.The aim of this work is to present clinical experience in the diagnosis, treatment and rehabilitation of patients with tumor-induced osteomalacia. MATERIALS AND METHODS: 40 patients with clinically-confirmed tumor-induced osteomalacia were included in the study, 34 of whom had the tumor localized, 27 underwent surgical treatment and 21 achieved stable remission. RESULTS: The median age was 48 [41; 63] years, 43% were men, the time left from the the onset of the disease was 8 [4; 10] years. Biochemical findings were hypophosphatemia 0.47 [0.4; 0.53] mmol/l, a decrease in the tubular reabsorption phosphate 62 [52; 67]%, and an increase in alkaline phosphatase of 183 [112; 294] units/l. At the time of diagnosis, 100% had multiple pathological fractures, only 10% could move independently, and 77.5% classified the pain as unbearable (8-10 points according to the 10-point pain syndrome scale ). Among the methods used to detect tumors, the most sensitive were scintigraphy with tectrotide with SPECT/CT 71.4% (20/28) and MRI 90% (18/20). In 35% of cases, the tumor was localized in soft tissues and in 65% in bone tissue; The tumor was most often detected in the lower extremities, followed by the head in frequency of localization. 18 patients currently have no remission and they receive conservative treatment (phosphorus and alfacalcidol n=15 and burosumab n=3). In case of achieving remission (n=21), regression of clinical symptoms and restoration of bone and muscle mass was observed. Extensive excision of the tumor without prior biopsy resulted in the best percentage of remission - 87%. CONCLUSION: Tumor-induced osteomalacia is characterized by severe damage to bone and muscle tissue with the development of multiple fractures, muscle weakness and severe pain syndrome. In laboratory diagnostics, attention should be paid to hypophosphatemia, a decrease in the tubular reabsorption phosphate index and increased alkaline phosphatase. The use of functional diagnostic methods with a labeled somatostatin analogue to the subtype 2 receptor and MRI with contrast enhancement are the most accurate methods of topical diagnostics. In case of localization of the tumor, a wide excision without a preliminary biopsy is recommended.

[Rare forms of hereditary endocrine neoplasia: co-existence of pituitary adenoma and pheochromocytoma/paraganglioma].

Functioning pituitary adenomas and pheochromocytomas/paragangliomas are rare in the general population. Pituitary adenomas occur in the familial setting in approximately 5% of cases, whereas pheochromocytomas/paragangliomas can be hereditary in 30-40% of cases. Hereditary syndromes associated with pituitary adenomas include multiple endocrine neoplasia types 1 and 4, familial isolated pituitary adenomas, and Carney complex. Hereditary syndromes associated with pheochromocytomas/paragangliomas and genes, mutations in which predispose to their development, are more numerous. The first clinical descriptions of the co-occurrence of pituitary adenoma and pheochromocytoma/paraganglioma in one patient date back to the mid 20th century, however delineating such a co-occurrence into a particular syndrome («3PAs¼ (pituitary adenoma, pheochromocytoma, paraganglioma)) was suggested only in 2015. To date, approximately 100 cases of such a co-occurrence have been described in the literature. Mutations in genes encoding subunits of succinate dehydrogenase complex II (SDHx) are revealed in the majority of cases, much less common are mutations in MAX, MEN1 and some other genes. This review summarizes the current information on the «3PAs¼ syndrome.

[Thyrotropin-secreting pituitary adenomas: clinical features and results of treatment in 45 patients].

BACKGROUND: Thyrotropin-secreting pituitary adenomas (TSH-PA) are a rare cause of thyrotoxicosis and account for 0.5-2% of all pituitary adenomas. Taking into account the rarity of the disease, it is extremely important to analyze each case of TSH-PA. AIM: To analyze the clinical characteristics and treatment outcomes of patients with TSH-PA, as well as to determine preoperative and early postoperative factors that predict long-term remission. MATERIALS AND METHODS: In a single-center retrospective study we analyzed clinical signs, laboratory and instrumental studies, as well as the treatment outcomes of patients with TSH-PA from 2010 to 2023. Preoperative factors, as well as TSH level measured on day 3 postoperatively, were evaluated for their ability to predict long-term remission when comparing groups of patients with and without remission. RESULTS: The study included 45 patients with TSH-PA (14 men, 31 women), with a median age of 45 years [30; 57]. The most common clinical manifestations of TSH-PA were: cardiac arrhythmia in 37 (82.2%) patients, thyroid pathology in 27 (60%), neurological disorders in 24 (53.35%). Most PAs were macroadenomas (n=35, 77.8%). Preoperatively, 28 (77.8%) patients received somatostatin analogs, and 20 (71.4%) patients were euthyroid at the time of surgery. Surgical treatment was performed in 36 (80%) patients, postoperative remission was achieved in 31 cases (86.1%). Administration of somatostatin analogues to patients with no remission/relapse after surgery lead to the remission in 100% of cases (4/4). A 1 mm increase in PA size raised the odds of recurrence/no remission by 1.15-fold,and PA invasion during surgery - by  5.129 fold. A TSH level on day 3 postoperatively above 0.391 mIU/L (AUC, 0.952; 95% CI 0.873-1.000; standard error 0.04; p<0.001) identifies patients with relapse/absence of remission after surgical treatment (sensitivity = 100%, specificity = 88.9%). CONCLUSION: The TSH-PA in the structure of PAs is extremely rare, and as a result, most of them are misdiagnosed and detected already at the stage of macroadenoma. The most effective method of treatment is transnasal transsphenoidal adenomectomy. Somatostatin analogues can be used as second-line therapy if surgical treatment is ineffective. We have proposed a possible model for postoperative TSH levels (>0.391 mU/l) to predict recurrence of TSH-PA, which requires validation on an expanded number of cases.

[A rare case of a functioning gonadotroph tumor accompanied by erythrocytosis in an elderly man].

Functioning gonadotroph adenomas are rare pituitary tumors secreting one or two gonadotropins (follicle-stimulating hormone (FSH) and/or luteinizing hormone (LH)), which are hormonally active. In the majority of cases, gonadotroph tumors are endocrinologically "silent" and make up more than a half of non-functioning pituitary adenomas. In this article we describe a rare clinical case of LH/FSH-secreting pituitary macroadenoma with bitemporal hemianopsia in a 62-year-old man. The patient underwent transnasal transsphenoidal adenomectomy, leading to remission. The distinctive feature of this case is the presence of secondary erythrocytosis due to endogenous hyperandrogenism, which required several blood exfusions to normaliza the level of hematocrit before surgery. It is noteworthy that clinical signs of erythrocytosis were present long before visual impairment. This clinical case demonstrates difficulties in the early diagnosis of functioning gonadotroph adenomas.

[Morphological characteristics of pituitary adenomas in the phenocopy of multiple endocrine neoplasia type 1].

BACKGROUND: Multiple endocrine neoplasia type 1 (MEN 1) is a rare autosomal dominant disorder caused by mutations in the MEN1 gene, which encodes the menin protein. If a patient has the MEN 1 phenotype in the absence of mutations in the MEN1 gene, the condition is classified as a phenocopy of this syndrome. Although significant progress has been made in understanding the function of menin, its role in the oncogenesis of the endocrine glands is still being elucidated. Due to its key role in physiological and pathological processes, the assessment of the menin expression can provide valuable information. AIM: to determine whether there are any differences in the expression of menin in the pituitary adenomas (PA) in patients with phenocopy of MEN 1 (phMEN 1) and genetically confirmed MEN 1 (gMEN 1) compared with their sporadic forms. MATERIALS AND METHODS: immunohistochemical assessment of the menin expression was carried out in PA of patients with gMEN 1, phMEN 1 and sporadic acromegaly (SA), surgically treated in 2008-2020. IHC was performed using antibodies to menin, PRL, GH, ACTH, FSH, TSH, Pit-1, T-box, ERA on previously prepared histological section. RESULTS: The study included 35 samples of PA: gMEN 1 - 9 samples, phMEN 1 - 12 (somatotropinomas + PHPT); CA - 14  samples. The patients were comparable by gender, adenoma size, and drug intake. The gMEN  1 group differed from phMEN 1 and SA by age (p = 0.0005). In patients with gMEN 1, the expression of menin varied from no staining (5/9) to intense cytoplasm staining. Cytoplasmic expression of menin was mainly present (11/12) in the phMEN 1. In the SA group, there was no staining in 1 case; nuclear expression was detected in 6/14 cases. The phMEN  1 group showed significantly higher cytoplasmic expression of menin than the gMEN  1 group (p = 0.006). The gMEN 1 group also differed from the SA group (p = 0.012). There were no statistically significant differences between the phMEN 1 and SA groups (p = 0.049). CONCLUSION: It was revealed that the menin expression, in general, is retained in phMEN 1 and SA groups, although with different localization in the cell structure (nucleus and / or cytoplasm). At the same time, the expression of menin varies greatly in patients with gMEN 1. According to the data obtained, it can be assumed that the pathogenesis of PA in phMEN 1 and SA may have similarities; however, there could be factors contributing to the appearance of several tumors of the endocrine glands in one person with phMEN 1. To understand this process, it is necessary to further study the genes associated with MEN 1, epigenetic factors, signaling pathways in which menin is involved.

Multiple bilateral hip fractures in a patient with dyskeratosis congenita caused by a novel mutation in the PARN gene.

We report a case of a young male patient with clinical signs of dyskeratosis congenita who presented with multiple bilateral low-traumatic hip fractures. Whole exome sequencing (WES) showed a previously unreported mutation in the poly(A)-specific ribonuclease (PARN) gene. Zoledronic acid 5 mg over 3 years was effective at preventing further fractures. A male patient was referred to our clinic at age 24 due to multiple bilateral hip fractures. At the time of admission, the patient's height was 160 cm and weight 40 kg; bone mineral density (BMD) at the lumbar spine was normal (L1-L4 0.0 Z-score). The patient was found to have abnormal skin pigmentation, hyperkeratosis of palms and soles, nail dystrophy, and signs of bone marrow failure (BMF). Bone fragility first presented at 5 years old with a wrist fracture, followed by multiple bilateral low-traumatic hip fractures without falls from 14 to 24 years. WES showed a previously unreported mutation (NM_002582.3: c.1652delA; p.His551fs) in the poly(A)-specific ribonuclease (PARN) gene. Flow fish telomere measurement result was 5.9 (reference range 8.0-12.6), which is consistent with the DC diagnosis. Permanent fixation with internal metal rods and zoledronic acid 5 mg over 3 years was effective at preventing further fractures over 4 years of follow-up. Additionally, BMF did not progress over 4 years of observation. DC associated with PARN gene mutations might predispose to low-traumatic multiple hip fractures in adolescents and young adults. Treatment with zoledronic acid in this case was effective and safe at preventing further fractures.

[Hereditary Cushing's syndrome caused by primary bilateral macronodular adrenal hyperplasia due to ARMC5 mutation with concomitant primary hyperparathyroidism: the first known case in Russia].

Primary bilateral macronodular adrenal hyperplasia (PBMAH), a genetically heterogeneous disease, is a rare cause of Cushing's syndrome. Until recently, few cases were attributed to mutations in known genes. However, in 2013, ARMC5, a newly discovered tumor suppressor gene, was identified. Further studies have shown that mutations in the ARMC5 gene are found in 25-55% of all PBMAH cases. This article describes a clinical case of hereditary Cushing's syndrome caused by PBMAH in a 37-year old patient. The patient's family history is remarkable for the presence of Cushing's syndrome and PBMAH in the patient's mother. Bilateral adrenalectomy was performed as the treatment of choice. Genetic analysis using whole-exome sequencing confirmed the hereditary cause of the disease, revealing a germline heterozygous mutation in the ARMC5 gene. The patient also had concomitant mild primary hyperparathyroidism, which had not been observed before in genetic carriers with the ARMC5 mutation.

[CDC73 mutations in young patients with primary hyperparathyroidism: A description of two clinical cases]. / Mutatsii v gene CDC73 u molodykh patsientok s pervichnym giperparatireozom (opisanie dvukh klinicheskikh sluchaev).

The article describes two clinical cases of severe primary hyperparathyroidism (PHPT) caused by parathyroid carcinoma in young female patients who underwent molecular genetic testing to rule out the hereditary forms of PHPT. In both patients, heterozygous germline nonsense mutations of tumor suppressor gene CDC73 encoding parafibromin (p.R91X and p.Q166X) were identified using next-generation sequencing with Ion Torrent Personal Genome Machine (Thermo Fisher Scientific - Life Technologies, USA). It is the first description of CDC73 mutations in Russia, one of the mutations is described for the first time in the world. Identification of germline mutations in the CDC73 gene in patients with PHPT necessitates regular lifelong screening for other manifestations of hyperparathyroidism-jaw tumor syndrome (HPT-JT), PHPT recurrence due to parathyroid carcinoma as well, and identification of mutation carriers among first-degree relatives.

[Multiple endocrine neoplasia type 1 syndrome with three classical components and chiasm glioma: specific features of target organ lesions and a clinical observation].

The article briefly reviews the specific features of target-organ lesions in multiple endocrine neoplasia type 1 (MEN1) syndrome and a clinical case of genetically confirmed MEN1 syndrome in a young female patient. Despite the relative rarity of this disease, timely diagnosis, treatment and screening for its main components are very important for the overall prognosis of patients with MEN1 and their first-degree relatives who are MEN1 gene mutation carriers. The described case is noteworthy for a number of specific features. The authors could find no account of optic chiasm glioma within the framework of MEN1 in the literature. Moreover, therapy-resistant somatoprolactinoma engages attention, which points to its aggressive nature with pituitary adenoma that is not been clearly visualized on magnetic resonance imaging. Of interest is the order of detection of neoplasms, in particular the manifestation of hypoglycemic episodes as a sign of organic hyperinsulinism. which have been initially regarded as epileptic seizures, after the use of sustained-release somatostatin analogues for the treatment of acromegaly.

[TYPE 1 MULTIPLE ENDOCRINE NEOPLASIA SYNDROME AND FAMILIAL ISOLATED HYPERPARATHYROIDISM].

Type 1 multiple endocrine neoplasia syndrome (MEN-1) is a rare autosomal dominant disorder caused by mutation in the MEN-1 gene and manifest as a combination of tumours of parathyroid glands, endocrine pancreas, and adenohypophysis. Familial isolated hyperparathyroidism (FIHP) is another rare autosomal dominant disorder characterized by the development ofparathyroid tumours as the sole endocrinopathy within a single family. The notion of FIHP encompasses different hereditary forms of primary hyperparathyroidism, such as a variant of MEN-1 syndrome. This paper is a brief literature review of the problems related to primary hyperparathyroidism, MEN-1, and FIHP. Also, It describes a family presenting with genetically confirmed MEN-1 syndrome, manifest as primary hyperparathyroidism.

[Multiple endocrine neoplasia type 1 variants and phenocopies].

Multiple endocrine neoplasia type 1 (MEN1) is a rare autosomal dominant hereditary disease due to a mutation in the MENI tumor suppressor gene. The risk of the disease in first-degree relatives of MEN1 mutation carriers is 50%. MENI gene mutations are not identified in 10-30% of familiar MEN1 patients and in 60-80% of sporadic MEN1 cases, which can be explained by mutations in the noncoding regions of the MEN1 gene, large gene deletions or mutations in other yet unknown genes. Molecular genetic testing can exclude the diagnosis of MEN1 in patients who do not harbor the MEN1 mutation, thus revealing a MEN1 phenocopy. This obviates the need for annual screening for the early detection of other remaining components of the disease and its risk in progeny.

[Toll-like receptor-mediated functional activity of mononuclear cells in children with neutropenia].

AIM: To study the Toll-like receptor (TLR)-mediated functional activity of peripheral blood mononuclear cells (PBMC) from children with different forms of neutropenia. MATERIALS AND METHODS: TLR-mediated functional activity of PBMC was evaluated by production of proinflammatory cytokines--TNF alpha and IFN alpha. Ligands for TLR1/2, TLR 2/6, TLR4, TLR5, and TLR9 were used to stimulate TNF alpha production by PBMC from healthy children and children with neutropenia. Ligands for TLR3, TLR4, TLR7, TLR7/8, TLR8, and TLR9 were used to induce production of IFN alpha. Levels of TNF alpha and IFN alpha were measured in PBMC supernatants by ELISA. The group of patients with neutropenia included 9 children with immune neutropenia and 3 children with congenital neutropenia. Control group consisted of 12 healthy children of the same age range. RESULTS: It was revealed that TLR2, TLR4, and TLR5 ligands have enhanced stimulating effect on TNF alpha production by PBMC of children with congenital neutropenia and had no effect on PBMC of children with immune neutropenia. Children with immune neutropenia are characterized by significantly increased IFN alpha production induced by ligands of TLR3, TLR8, and TLR9. CONCLUSION: Revealed changes of TLR-mediated functional activity of PBMC from children with various forms of neutropenia may play significant role in development and course of infections in these patients.

[Retrospective evaluation of blood immunologic parameters in the course of remission of acute lymphoblastic leukemia in children]. / Retrospektivnaia otsenka immunologicheskikh pokazatelei krovi u detei v raznye sroki remissii ostrogo limfoblastnogo leikoza.

The authors investigated cellular and humoral immunity in 53 children over 3 years of age suffering from acute lymphoblastic leukemia. The children had remission lasting from 6 to 120 months and were followed up for 7-14 years after the diagnosis was made. The treatment was performed according to programs of polychemotherapy practiced in 1981-1988. In November of 1995 42 children were alive, 15 had the disease for 10 years. Lymphocytopenia (absolute number of T-cells and B-cells fell 3-5 and 2-3-fold, respectively) was reported in all the examinees both in early remission and later (6-12, 24-60, 60 and more months since the disease onset). In early remission there was a significant reduction in the serum IgG, IgA and IgM. In children with ALL lethal outcome serum IgM and absolute number of E-RFCa dropped in early remission more significantly indicating deep drug-induced depression of lymphocytopoiesis. After 5 years of treatment the pool of peripheral T-lymphocytes and T/B lymphocyte proportion changed for the best, though their absolute number was subnormal. Serum IgG, IgA and circulating immune complexes were 1.3-1.5 times higher than normal which may be explained by gastrointestinal pathology and food allergy in the majority of children treated.

[Changes in the activity of endonucleolysis of nuclear DNA in children with acute leukemia]. / Izmenenie aktivnosti éndonukleoza DNK-kletochnykh iader pri ostrom leikoze u detei.

The previously established fact of low activity of Ca, Mg-dependent endonucleolysis of cell nucleus DNA in lymphoproliferative diseases (CME-activity) brought the authors to study intranuclear characteristics of lymphoid cells in childhood acute lymphoblastic leukemia (ALL). The intensity of DNA-endonucleolysis was measured in 0.7% agarose gel using electrophoresis. Peripheral blood and bone marrow samples from 13 untreated ALL patients and 23 children in remission were examined. The age of the patients ranged from 4 to 14 years. CME-activity before treatment appeared to be 2-10 times less than normal in 8 out of 13 patients. In bone marrow cell nuclei CME-activity was universally reduced 3-20-fold. In ALL remission endonuclease activity in blood and bone marrow cells returned to normal.

[Evaluation of hematopoietic and stromal cells-precursors in children with neutropenia]. / Otsenka krovetvornykh i stromal'nykh kletok-predshestvennikov pri neitropeniiakh u detei.

The content of hemopoietic and stromal precursor-cells was studied in the bone marrow of 46 children with congenital neutropenia and of 2 children with chronic benign neutropenia. It was found that the number of GM-CFC and F-CFC in the bone marrow of patients with chronic benign neutropenia did not differ from that in the control group of normal children, and the lowering of the neutrophil number in the blood was, probably, associated with their redistribution mechanism or increased destruction in the body. Multiple defects of hemopoietic and stromal tissue were detected in children with a hereditary form of congenital neutropenia when anomalous proliferation of F-CFC and disorders in GM-CFC differentiation led to hypoplasia of granulocytic growth stem and neutropenia.

[Precursor cells of the granulomonocytopoiesis in children with immune neutropenia]. / Kletki-predshestvenniki granulomonotsitopoéza u detei s immunnoi neitropeniei.

The study of precursor cells of granulocytes and macrophages has shown that in children with immune neutropenia the higher division of granulopoiesis-committed precursor cells is not affected, while the defect is localized in the periphery of hemopoiesis, and it is induced by increased destruction of neutrophils.

[Two-dimensional size-charge distribution of bone marrow cells in children with chronic immune neutropenia]. / Dvukhmernoe raspredelenie razmer-zariad kletok kostnogo mozga u detei s kronicheskoi immunnoi neitropeniei.

Physical characteristics of bone marrow cells of normal donors were comparatively studied with those of children with immune neutropenia. As a result of the bone marrow cell separation in the density gradient according to their sedimentation rate, fractions enriched with cells of one histogenetic series (lymphoid, erythroid and granulocytic) were obtained. Electrophoretic mobility of immature granulocytes in normal donors differed from that in children with immune neutropenia.