Phase Equilibria of the In-Pd-Sn System at 500 °C and 800 °C: Experimental Study and CALPHAD Modeling

Phase equilibria in the In-Pd-Sn system were investigated by a combination of key experiments and thermodynamic modeling. Partial isothermal sections at 500 °C and 800 °C of the In-Pd-Sn system for Pd contents above 66 at.% have been plotted experimentally using scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDX) and X-ray diffraction (XRD). The solubility of the third component in binary compounds InPd₃ and Pd₃Sn was determined. The new ternary compound τ₁ was found in Pd contents ranging from 20 to 25 at.% and at Sn contents varying from 5 to approximately 17 at.% Sn. This compound crystallizes in an Al₃Ti-type tetragonal structure. Isostructural InPd₂ and Pd₂Sn phases from the In-Pd and Pd-Sn binary compositions form a continuous phase field in the ternary system at both temperatures. The temperatures of the solidus, liquidus, and phase transitions of the alloys along the Pd-In50Sn50 line were measured using DTA/DSC. Thermodynamic calculation of the In-Pd-Sn ternary system is performed using the CALPHAD method using the Thermo-Calc^® software. The thermodynamic properties of the disordered fcc and liquid phases were described by the Redlich-Kister-Muggianu model. To describe intermetallic phases, namely, InPd₃, Pd₃Sn, τ₁ and Pd₂(In_xSn_1-x), a two-sublattice models was used. Thermodynamic description of the In-Pd-Sn system obtained in this study is in good agreement both with our results and the published experimental data.

[Clinical guidelines «Precocious puberty»]

The precocious puberty is an urgent problem of pediatric endocrinology characterized by clinical and pathogenetic heterogeneity. The appearance of secondary sex characteristics before the age of 8 years in girls and 9 years in boys requires timely diagnosis and the appointment of pathogenetically justified treatment in order to achieve the target indicators of final growth and prevent social deprivation. The developed clinical guidelines are the main working tool of the practitioner. They briefly and structurally present the main information about the epidemiology and modern classification of рrecocious puberty, methods of its diagnosis and treatment based on the principles of evidence-based medicine.

Comparative assessment of energy metabolism, body composition and metabolic features in children with hypothalamic and simple obesity

Background: Hypothalamic obesity often develops after surgical treatment of craniopharyngioma and is characterized by rapid weight gain, high frequency of metabolic disorders, body composition specificity and resistance to standard lifestyle modification approaches and medication therapy of obesity. Recent studies show that one of the mechanisms, explaining weight gain in these children is decrease in resting energy expenditure (REE).

Aims: To compare REE, body composition parameters, and the frequency of metabolic disorders in children with hypothalamic and simple obesity.

Materials and methods: The study included 60 obese children aged 7 to 17 years, divided into two groups. The study group included 20 children with hypothalamic obesity, developed after craniopharyngioma treatment. The control group consisted of 40 children with simple obesity. Body composition, REE, and metabolic disorders were associated in all children.

Results: Children with hypothalamic obesity showed a significant decrease of resting energy expenditure. The average decrease in REE was 13.1%, but in single patients it reached 33.4%. The percentage of fat mass in hypothalamic and simple obesity does not differ significantly (39.7% [36.2; 42.6] vs 38.8 % [35.9; 43.2]; p=0.69). Screening for metabolic disorders revealed a high prevalence of metabolic disorders in hypothalamic obesity: impaired glucose tolerance - in 10%; dyslipidemia - 55%, insulin resistance-50%, non-alcoholic fatty liver disease - 60 %.

Conclusions: Children with hypothalamic obesity showed a significant decrease of resting energy expenditure. When planning a diet in this group of patients it is preferable to use indirect calorimetry. Hypothalamic obesity even at an early age is associated with a high frequency of metabolic disturbance. Hypothalamic obesity in children is not associated with more pronounced hyperinsulinemia and insulin resistance compared to the simple obesity.

[Continuous subcutaneous infusion of somatostatin analogues in the treatment of congenital hyperinsulinism]

BACKGROUND

Congenital hyperinsulinism (CHI) is a severe disease with a high risk of development of neurological complications due to persistent hypoglycemia. The use of an analog of somatostatin (octreotide) in patients with the resistance to the first-line drug allows to avoid surgical intervention. However, the octreotide is currently used in the form of frequent fractional injections due to the short duration of it’s effect. We present in this article our own experience of using octreotide in continuous subcutaneous infusion in pediatric patients in order to improve the quality of life. AIM To evaluate the efficiency and safety of the regime of continuous subcutaneous infusion of octreotide with the use of micro-dispensers (pumps) in children with diazoxide-resistant course of CHI.

MATERIALS AND METHODS

An observational single-centre dynamic research was carried out on the basis of the Federal State Budgetary Institution «Endocrinology Research Centre» of the Ministry of Health of the Russian Federation. The study included pediatric patients with CHI and proven diazoxide-resistant course who were initially treated with octreotide in the form of intermittent subcutaneous injections. The researches compared the indicants of efficiency and safety of therapy on treatment of intermittent injections and after transfer to continuous subcutaneous infusion of the drug. The duration of each method of administration was at least 2 weeks.

RESULTS

16 patients took part in the research. The median for the total duration of octreotide usage in the examined patients was 3 months. According to the results of the work, the use of micro-dispensers for continuous subcutaneous administration of octreotide allowed to reduce the number of patients with episodes of hypoglycemia for more than 4 times (13/16 vs. 3/16); p=0,001). Also, there was a significant decrease in the number of patients with hyperglycemic episodes (4/16 vs. 0/16); p=0.000) and reduced dose of intravenous glucose (6.8 vs 5.2 mg/kg/min; p=0.042) as a result of continuous therapy, which indicates the advantages of smooth continuous administration comparing to single injections. We have not detected any significant side effects of the treatment. Elevated liver enzyme levels, dyspeptic symptoms and gallstone formation in some patients did not require cancellation of therapy. There were no hormonal disorders in the form of hypothyroidism and somatotropic hormone deficiency against the background of continuous octreotide infusion.

CONCLUSIONS

Thus, the use of octreotide in patients with diazoxide-resistant course of СHI in continuous subcutaneous infusion using pumps has a number of advantages over the standard method of intermittent subcutaneous injection. This method of administration allows to achieve better glycemic control and reduce the risks from infusion therapy with highly concentrated glucose solutions, which undoubtedly improves the quality of life of patients.

[Assessment of autoantibodies against 21-hydroxylase in the diagnosis of primary autoimmune adrenal insufficiency]

Primary adrenal insufficiency is manifested by a deficiency of adrenal cortex hormones and can lead to a life-threatening condition. Early diagnosis is key to patient survival. Auto-antibodies to one of the adrenal steroidogenesis enzymes, 21-hydroxylase, are an immunological marker of autoimmune adrenal insufficiency. On the one hand, the study of antibodies to 21-hydroxylase is a method that helps establish the etiology of the disease – the autoimmune genesis of adrenal gland damage. On the other hand, the determination of autoantibodies to 21-hydroxylase is the only prognostic factor of the risk of adrenal insufficiency, which makes it possible to prevent the development of acute adrenal crisis. The article provides a brief literature review on autoantibodies to 21-hydroxylase and the pathogenesis of autoimmune adrenal insufficiency, and a series of clinical cases that illustrates the significant role of autoantibodies to 21-hydroxylase in diagnosis of adrenal insufficiency.

[Laparoscopic adrenalectomy for benign adrenal tumors in pediatric surgical practice]

OBJECTIVE

To estimate the results of minimally invasive adrenalectomy in children and compare our data with worldwide results.

MATERIAL AND METHODS

There were 65 patients aged from 3 months to 17 years with different organic diseases of adrenal glands. Children have undergone surgery for the period since 2003 to 2018.

RESULTS

Incidentalomas accounted 33.8% of all resected tumors. Bilateral lesion was diagnosed in 12% of patients. The largest neoplasm (12 cm) was diagnosed in a 9-year-old child. Intraoperative bleeding occurred in 2 patients. Endoscopic surgery did not require conversion in any case.

CONCLUSION

We accumulated unique experience of laparoscopic resection of benign lesions of adrenal glands. Our results are satisfactory and comparable with data of other national and foreign colleagues. Only close collaboration of pediatric surgeons and endocrinologists could lead to successful and safe treatment of these patients. Patients with suspected malignancies should receive treatment at special hospitals with oncological service.

Disorder of sex development 46,XY associated with mutations in the gene MAP3K1. The report of clinical cases

The disorders of sex development (DSD) 46,XY may be caused by mutations in a number of genes involved in the gonadal differentiation. The XY sex inversion can be also due to disturbances at the level of mitogen-activated protein kinase (MAPK) kinase kinase 1 gene (MAP3K1) and MAPK-signaling pathway. During the last decade, the involvement of the MAPK pathway in the SRY gene up-regulation during the formation of male gonadal sex in mammals has been demonstrated. The role of MAPK-signaling pathway in the human sex determination is not fully understood. Probably, MAP3K1 and the MAPK-signaling pathway are one of the genetic pathways controlling normal development of human testis. So far, several families and sporadic cases of 46,XY DSD due to mutations in MAP3K1 gene have been reported in the literature. Clinical presentation of DSD in these patients varies from female phenotype with normal externalia to male phenotype with hypospadias. We describe rare cases of the DSD 46,XY (a family case of DSD in uterine sisters and a sporadic case) with mutations in the MAP3K1 gene that haven’t been previously described. The article also presents brief literature review on this pathology.

Expanding the Phenotypic and Genotypic Landscape of Autoimmune Polyendocrine Syndrome Type 1

Context

Autoimmune polyendocrine syndrome type 1 (APS-1) is a rare monogenic autoimmune disease caused by mutations in the autoimmune regulator (AIRE) gene and characterized by chronic mucocutaneous candidiasis, hypoparathyroidism, and primary adrenal insufficiency. Comprehensive characterizations of large patient cohorts are rare.

Objective

To perform an extensive clinical, immunological, and genetic characterization of a large nationwide Russian APS-1 cohort.

Subjects and Methods

Clinical components were mapped by systematic investigations, sera were screened for autoantibodies associated with APS-1, and AIRE mutations were characterized by Sanger sequencing.

Results

We identified 112 patients with APS-1, which is, to the best of our knowledge, the largest cohort described to date. Careful phenotyping revealed several additional and uncommon phenotypes such as cerebellar ataxia with pseudotumor, ptosis, and retinitis pigmentosa. Neutralizing autoantibodies to interferon-ω were found in all patients except for one. The major Finnish mutation c.769C>T (p.R257*) was the most frequent and was present in 72% of the alleles. Altogether, 19 different mutations were found, of which 9 were unknown: c.38T>C (p.L13P), c.173C>T (p.A58V), c.280C>T (p.Q94*), c.554C>G (p.S185*), c.661A>T (p.K221*), c.821del (p.Gly274Afs*104), c.1195G>C (p.A399P), c.1302C>A (p.C434*), and c.1497del (p.A500Pfs*21).

Conclusions

The spectrum of phenotypes and AIRE mutation in APS-1 has been expanded. The Finnish major mutation is the most common mutation in Russia and is almost as common as in Finland. Assay of interferon antibodies is a robust screening tool for APS-1.

Response of pure red cell aplasia to cyclophosphamide after failure of mycofenolate mofetil in a patient with polyglandular syndrome type I

A 26-year-old female with the classic major and minor components of autoimmune polyglandular syndrome type 1 was diagnosed as having pure red cell aplasia. Treatment with 1.5 g/d mycofenolate mofetil for 3 months failed to restore erythroid production. Treatment with cyclosporine A produced a good partial response but led to renal toxicity and was therefore substituted with cyclophosphamide, which had a good partial effect and lasted for 18 months. The relapse of anemia was not observed during the 6-month follow-up period after the cessation of treatment.

Autoimmune polyglandular syndrome type 1 in Russian patients: clinical variants and autoimmune regulator mutations

BACKGROUND

Autoimmune polyglandular syndrome type 1 (APS-1) (OMIM 240300) is a rare autosomal recessive disorder associated with three major manifestations: chronic mucocutaneous candidiasis, hypoparathyroidism, and adrenal insufficiency. There are, however, multiple minor components of APS-1 that induce significant phenotype variability. Subsequently, the diagnosis of APS-1 during early stages is often challenging.

AIM

We aimed to provide clinical and mutational data for a large number of APS-1 patients in the Russian population.

METHODS

We analyzed clinical variations and component prevalence in APS-1 patients. DNA screening for autoimmune regulator (AIRE) gene mutations was performed in established APS-1 patients and in patients with the single components of chronic mucocutaneous candidiasis, hypoparathyroidism, adrenal insufficiency, or alopecia.

RESULTS

We identified 46 patients from 42 families with APS-1. Eighteen different components were present in the patients, including very rare conditions - bone dysplasia and retinitis pigmentosa. We identified 10 different mutations, 3 of which were novel (M1T, E298K, c1053_1060del). The common Finnish mutation, R257X, was the most frequent in our population, present in 64/92 (70%) of the alleles.

CONCLUSION

We found that the R257X AIRE mutation is common in Russian APS-1 patients. The majority of children with hypoparathyroidism and chronic mucocutaneous candidiasis were carriers of the AIRE mutations.

[Clinical polymorphism of congenital X-linked adrenal hypoplasia]

Congenital adrenal hypoplasia is a rare clinical variant of primary adrenal insufficiency. Two forms of this disease are known, one of which is inherited in an autosomal recessive manner (including IMAGe syndrome - a combination of adrenal hypoplasia with intrauterine growth retardation, metaphysical dysplasia and abnormal genital structure, OMIM 300290), and the other has X-linked nature of inheritance (DAX-1 gene defect). X-linked adrenal hypoplasia is relatively more common and studied in more detail.Congenital X-linked adrenal hypoplasia is manifested by a combination of primary adrenal insufficiency and hypogonadotropic hypogonadism and is caused by defects in the DAX-1 gene (measurement-sensitive sex reversal, adrenal hypoplasia congenital, critical region on the X chromosome, gene-1).

[The nonclassical form of congenital adrenal cortical dysfunction in adolescent girls]

The study was undertaken to define the frequency of nonclasslcal 21-hydroxylase deficiency confirmed by CYP21 gene mutations in girls with pubertal hyperandrogenlsm, to estimate the value of clinical and hormonal markers of nonclasslcal 21-hydroxylase deficiency. Eighty-five girls aged 5-17 years who had hyperandrogenlsm (pubertas precox, hirsutism, acne vulgaris). All the examinees underwent adrenocorticotropic hormone (ACTH) (Synacthen-depot) test. After detecting the hormonal markers oj"nonclassical21-hy-droxylase deficiency (the baseline level of 17- О HP being was above 9 nmol/l and/or above 45 nmol/l after A CTH stimulation), the authors analyzed the most common CYP21 gene mutations. The frequency of nonclassical 21-hydroxylase deficiency supported by CYP21 mutations In the girls with hyperadrogenlsm was 8.3%. There were no clinical differences between the nonclassical form of 21-hydroxylase deficiency and other forms of hyperandrogenlsm. The high baseline 17-OHP ( > 20 nmol/l) is the most specific hormonal marker of nonclasslcal 21-hydroxylase deficiency. Glucocorticoid therapy is indicated for patients with substantially accelerated growth and bone maturation and in those with menstrual irregularities as oligomenorrhea or amenorrhea.

[Lipoid adrenal hyperplasia caused by earlier unknown 21STAR gene mutations]

Lipoid adrenal hyperplasia (LAH) is a most severe type of congenital adrenal cortical dysfunction (CACD). In this type of CACD, there is defect in the conversion of cholesterol to pregnenolone, as a consequence the production of all steroid hormones was impaired in both the adrenals and gonads. Defects of the STAR gene encoding for a steroidogenic acute regulatory (StAR) protein underlie the disease in most cases. Until the present time, there have been no reports on cases of LAH in the Russian literature. The diagnosis of LAH was established by the authors in three genetic girls aged 2.3 years, 6 and 7 months who had a normal structure of the external genitalia and in whom the disease was marked by manifestations of primary hypoadrenocorticism at the age of 21, 2, and 10 days, respectively. A hormonal study failed to show elevated levels of Cortisol and 17-hydroxyprogesterone in response to adrenocorticotropic hormone stimulation. A molecular genetic study revealed the following STAR gene defects: P129AC/W250X, IVS5-1G, and W147X, respectively. Р129ЛС, IVSS, and W147X mutations have not been earlier described. The data of the observation emphasizes the need of including LAH into the algorithm of differential diagnosis of CACD in children with the normal female structure of the external genitalia. The molecular genetic analysis should be prominent in diagnosing LAH, by taking into account the lack of hormonal markers of the disease.

[Effects of carnitine and cobamamide on the dynamics of mental work capacity in patients with anorexia nervosa]

The authors relate the results of studying intellectual work fitness in patients with anorexia nervosa (in the stage of cachexia) receiving the vitamin-like drugs carnitine and cobamamide. It has been shown that the long-term food deprivation leads to a reduction of intellectual work fitness, lability of productivity, fluctuations in the work quality, appearance of latent fatigue. In spite of the fact that standard nonspecific treatment ameliorates intellectual work fitness, it does not lead to its normalization. The use of carnitine and cobamamide in the course of nonspecific treatment results in the reduction of the time spent on task implementation, a rise of the work rate as compared to the control group. However, this does not fully remove latent fatigue and does not bring about complete recovery to normal of intellectual work fitness. The combined use of carnitine and cobamamide eliminates fluctuations in the work rate and normalizes the scope and productivity of intellectual work.

[Role of the age factor in forming the clinical picture of anorexia nervosa]

The results of long-term clinical and experimental-psychological studies of patients with nervous anorexia were analyzed from the point of view of age psychology. Such approaches permitted to distinguish a peculiarity in the formation mechanism of this form of pathology. Dynamical studies of the moving forces in the personality development in morbid conditions allowed one to distinguish certain disorders in the process of periodization of the mental development. This in its turn exerts influence on the development of nervous anorexia.