Evaluation of the age-specific relationship between PTH and vitamin D metabolites.

A commonly used method for determining vitamin D sufficiency is the suppression of excess PTH secretion. Conventionally, the main circulating vitamin D metabolite 25(OH)D is used for this assessment, however, the cut-off data for this parameter vary widely in the literature. The role of other metabolites as markers of vitamin D status is actively debated.

Cyanoacetohydrazide as a Novel Derivatization Agent for the Determination of UHPLC-HRMS Steroids in Urine.

The possibility of cyanoacetohydrazide usage as a novel derivatizing agent is demonstrated in the presented article, and a comparison with hydroxylamine as the most commonly used reagent is provided. Optimal conditions for steroid derivatization with cyanoacetohydrazide are provided. According to the collected data, the maximum yield of derivatives was observed at pH 2.

[Overcoming therapy resistance in prolactinomas: from perspectives to real clinical practice].

The main treatment option of prolactin-secreting pituitary adenomas is dopamine agonist therapy, which demonstrates prolactin level normalizing and reducing the size of an adenoma in the majority of cases. However, significant amount of patients - about 20% - poorly responds even to high doses of dopamine agonists that is explained by the resistance to therapy. The occurrence of pharmacodynamic characteristics is one of the causes responsible for the development of resistance to typical therapy.

Dynamic Evaluation of Vitamin D Metabolism in Post-Bariatric Patients.

Background: findings from the previously conducted studies indicate altered regulatory mechanisms of calcium and vitamin D metabolism in obese patients and a role for bariatric surgery in regulating vitamin D metabolism; however, the available data is controversial and does not provide an adequate understanding of the subject.

Methods: we evaluated serum parameters of vitamin D and mineral metabolism (vitamin D metabolites (25(OH)D, 25(OH)D, 1,25(OH)D, 3-epi-25(OH)D, and 24,25(OH)D), vitamin D-binding protein (DBP), free 25(OH)D, fibroblast growth factor 23 (FGF-23), parathyroid hormone (PTH), total calcium, albumin, phosphorus, creatinine, magnesium) in 30 patients referred for bariatric surgery in comparison with 30 healthy volunteers of similar age, sex and baseline 25(OH)D. Patients were also followed up with repeated laboratory assessments 3 months and 6 months after surgery.

[Features of steroidogenesis and arterial hypertension in men in different types of "physiological" male hyperandrogenism].

Aim: To reveal the peculiarities of steroidogenesis and arterial hypertension in «physiological» hyperandrogenism in men.

Materials And Methods: One-stage simultaneous study. The groups of men with hyperandrogenism caused by increased total testosterone (n=34) and those with hyperandrogenism caused by increased dihydrotestosterone (DHT) (n=66) were compared.

Serum Vitamin D Metabolites by HPLC-MS/MS Combined with Differential Ion Mobility Spectrometry: Aspects of Sample Preparation without Derivatization.

In current clinical practice, a thorough understanding of vitamin D metabolism is in high demand both for patients with various diseases and for healthy individuals. Analytical techniques that provide simultaneous measurement of multiple metabolites are preferred. Herein, the development of an HPLC-DMS-MS/MS method for the quantitation of vitamin D compounds (25(OH)D, 25(OH)D, 1,25(OH)D, 3-epi-25(OH)D, 24,25(OH)D, and D) in serum is described.

[Steroid profiling characteristics in pediatrc adrenal diseases].

Background: Adrenocortical adenomas are often followed with steroid hormones hyperproduction, and therefore determination of their concentration plays an important role in the differential diagnosis of adrenal diseases. Steroid profiling by tandem mass spectrometry is one of the main diagnostic methods in steroidogenesis characterization. Currently plasma and urinary steroid profiling is of particular interest in differential diagnosis and subtyping patients with adrenocortical adenomas.

[The study of blood serum trace elements in comparison with the structural and functional characteristics of goiter and the carriage of antithyroid antibodies in some regions of Russia].

The study of the sufficiency with essential trace elements in the context of thyroid pathology is especially relevant, since the development and progression of thyroid diseases have various pathogenetic mechanisms, which largest proportion is provoked by insufficient intake of key trace elements, primarily iodine. of the research was obtaining primary data on the sufficiency with essential trace elements of the population in the some regions of the Russian Federation, comparing the data obtained with the prevalence of goiter and the carriage of antibodies to thyroid peroxidase (AT-TPO). .

Parameters of Vitamin D Metabolism in Patients with Hypoparathyroidism.

Only a few studies evaluating the metabolism of vitamin D in patients with hypoparathyroidism (HypoPT) have been performed thus far, and, in particular, they mainly investigated the process of vitamin D activation (specifically, 1α-hydroxylation). This study, therefore, aimed to evaluate the extended spectrum of vitamin D metabolites in patients with HypoPT compared to healthy individuals. We examined 38 adult patients with chronic HypoPT in comparison to 38 healthy adults.

Impaired Vitamin D Metabolism in Hospitalized COVID-19 Patients.

There is increasing data regarding the association between vitamin D and COVID-19. This study aimed to reveal the alterations of vitamin D metabolism in the setting of COVID-19. We examined 119 adult COVID-19 inpatients and 44 apparently healthy adult individuals with similar serum 25OH-D3 levels as a reference group.

[Features of steroidogenesis in men with hypogonadism and type 2 diabetes].

Background: BACKGROUND: Type 2 diabetes mellitus (DM2) in men is associated with a high incidence of hypogonadism. Testosterone is a steroid hormone and one of the final metabolites of steroidogenesis, which causes interest in assessing the content of key steroid hormones, their precursors and metabolites in hypogonadal and eugonadal men with T2DM.

Aims: AIMS: Assessment of the features of steroidogenesis in men with hypogonadism in T2DM using tandem mass spectrometry.

Evaluation of Vitamin D Metabolism in Patients with Type 1 Diabetes Mellitus in the Setting of Cholecalciferol Treatment.

In this prospective controlled study, we examined 25 adults with adequately controlled (HbA1c level < 8.0%) type 1 diabetes mellitus (T1DM) and 49 conditionally healthy adults, intending to reveal the diversity of vitamin D metabolism in the setting of cholecalciferol intake at a therapeutic dose. All patients received a single dose (150,000 IU) of cholecalciferol aqueous solution orally.

Unusual Fusion of α-Fluorinated Benzophenones under McMurry Reaction Conditions.

By exposure of α-fluorinated benzophenones to McMurry reaction conditions, we have observed the remarkable formation of 9,10-diphenylanthracene derivatives. This unexpected transformation necessitates the cleavage of the exceptionally stable aromatic C-F bond under mild McMurry conditions. In this work, the condensation of several related fluorinated benzo- and acetophenones has been investigated, which allow us to propose a domino-like fusion mechanism for this unusual transformation.

Evaporation Study of an Ionic Liquid with a Double-Charged Cation.

The evaporation of a dicationic ionic liquid, 1,3-bis(3-methylimidazolium-1-yl)propane bis(trifluoromethanesulfonyl)amide ([C(MIm)][TfN]), was studied by Knudsen effusion mass spectrometry. Its evaporation is accompanied by a partial thermal decomposition producing monocationic ionic liquids, 1,3-dimethylimidazolium and 1-(2-propenyl)-3-methylimidazolium bis(trifluoromethanesulfonyl)amides, as volatile products. This decomposition does not affect the vaporization characteristics of [C(MIm)][TfN], which were established to be as follows.

Tightly Bound Double-Caged [60]Fullerene Derivatives with Enhanced Solubility: Structural Features and Application in Solar Cells.

A series of novel highly soluble double-caged [60]fullerene derivatives were prepared by means of lithium-salt-assisted [2+3] cycloaddition. The bispheric molecules feature rigid linking of the fullerene spheres through a four-membered cycle and a pyrrolizidine bridge with an ester function CO R (R=n-decyl, n-octadecyl, benzyl, and n-butyl; compounds 1 a-d, respectively), as demonstrated by NMR spectroscopy and X-ray diffraction. Cyclic voltammetry studies revealed three closely overlapping pairs of reversible peaks owing to consecutive one-electron reductions of fullerene cages, as well as an irreversible oxidation peak attributed to abstraction of an electron from the nitrogen lone-electron pair.

[The comparative analysis of the results of detection of testosterone in blood serum applying analyzers Architect and Vitros and tandem mass-spectrometry, a highly efficient fluid chromatography technique.].

The testosterone is a key element of hypothalamus hypophysis gonad system. Its physiological role in males is well known and consists primarily in formation of male phenotype and support of spermatogenesis. The evaluation of androgenic status is necessary in case of such wide specter of clinical symptoms and pathological states as hypogonadism, delayed of premature puberty, polycystic ovary syndrome, particular types of cancer, etc.

Fullerene as Photocatalyst: Visible-Light Induced Reaction of Perfluorinated α,ω-Diiodoalkanes with C.

Solution phase photochemical reaction of fullerene with perfluorinated alkyldiiodides I-R-I can be efficiently initiated by visible range irradiation that targets solely the fullerene component. Photoinduced electron transfer from fullerene onto the diiodide component effects dissociative formation of alkyl radicals RI subsequently consumed by C to give the principal detectable radical intermediate CRI. Experimentally established second-order kinetics with respect to the fullerene concentration evidence that fullerene plays its two roles of photocatalyst and reactant in a decoupled fashion, which suggests its catalytic ability to be of potential use in more complex photochemical systems.