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(InxSn1-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.

[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.

[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.

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.