Effect of Carbon Dots Concentration on Electrical and Optical Properties of Their Composites with a Conducting Polymer.

CQD/PEDOT: PSS composites were prepared via the hydrothermal method from glucose carbon quantum dots (CQDs) and an aqueous solution of PEDOT:PSS conducting polymer and their electrical and optical properties were investigated. The morphology and structure of these samples were investigated by AFM, SEM, EDX, and EBSD. It was found that the CQDs and CQD/PEDOT:PSS composites had a globular structure with globule sizes of ~50-300 nm depending on the concentration of PEDOT:PSS in these composites. The temperature dependence of the resistivity was obtained for the CQD/PEDOT:PSS (3%, 5%, 50%) composites, which had a weak activation character. The charge transport mechanism was discussed. The dependence of the resistivity on the storage time of the CQD/PEDOT:PSS (3%, 5%, 50%) composites and pure PEDOT:PSS was obtained. It was noted that mixing CQDs with PEDOT:PSS allowed us to obtain better electrical and optical properties than pure CQDs. CQD/PEDOT: PSS (3%, 5%, 50%) composites are more conductive composites than pure CQDs, and the absorbance spectra of CQD/PEDOT:PSS composites are a synergistic effect of interaction between CQDs and PEDOT:PSS. We also note the better stability of the CQD/PEDOT:PSS (50%) composite than the pure PEDOT:PSS film. CQD/PEDOT: PSS (50%) composite is promising for use as stable hole transport layers in devices of flexible organic electronics.

Familial Acromegaly and Bilateral Asynchronous Pheochromocytomas in a Female Patient With a MAX Mutation: A Case Report.

Background: There are very few cases of co-occurring pituitary adenoma (PA) and pheochromocytomas (PCC)/paragangliomas caused by MAX mutations. No cases of familial PA in patients with MAX mutations have been described to date. Case Presentation: We describe a 38-year-old female patient, presenting with clinical and biochemical features of acromegaly and PCC of the left adrenal gland. Whole-exome sequencing was performed [NextSeq550 (Illumina, San Diego, CA, USA)] identifying a nonsense mutation in the MAX gene (NM_002382) [c.223C>T (p.R75X)]. The patient had a medical history of PCC of the right adrenal gland diagnosed aged 21 years and prolactinoma diagnosed aged 25 years. Cabergoline treatment was effective in achieving remission of prolactinoma at age 33 years. The patient's father who died at age 56 years of a heart attack had a medical history of PA and prominent acromegalic features, which supports the familial presentation of the disease. Conclusion: This clinical case gives an insight into the clinical presentation of familial PA and PCC probably associated with a MAX mutation.

Investigation of the Morphology and Electrical Properties of Graphene Used in the Development of Biosensors for Detection of Influenza Viruses.

In this study, we discuss the mechanisms behind changes in the conductivity, low-frequency noise, and surface morphology of biosensor chips based on graphene films on SiC substrates during the main stages of the creation of biosensors for detecting influenza viruses. The formation of phenylamine groups and a change in graphene nano-arrangement during functionalization causes an increase in defectiveness and conductivity. Functionalization leads to the formation of large hexagonal honeycomb-like defects up to 500 nm, the concentration of which is affected by the number of bilayer or multilayer inclusions in graphene. The chips fabricated allowed us to detect the influenza viruses in a concentration range of 10-16 g/mL to 10-10 g/mL in PBS (phosphate buffered saline). Atomic force microscopy (AFM) and scanning electron microscopy (SEM) revealed that these defects are responsible for the inhomogeneous aggregation of antibodies and influenza viruses over the functionalized graphene surface. Non-uniform aggregation is responsible for a weak non-linear logarithmic dependence of the biosensor response versus the virus concentration in PBS. This feature of graphene nano-arrangement affects the reliability of detection of extremely low virus concentrations at the early stages of disease.

Minigene splicing assessment of 20 novel synonymous and intronic glucokinase gene variants identified in patients with maturity-onset diabetes of the young.

The next-generation sequencing (NGS) has become a routine method for diagnostics of inherited disorders. However, assessment of the discovered variants may be challenging, especially when they are not predicted to change the protein sequence. Here we performed a functional analysis of 20 novel or rare intronic and synonymous glucokinase (GCK) gene variants identified by targeted NGS in 1,130 patients with maturity-onset diabetes of the young. Human Splicing Finder, ver 3.1 and a precomputed index of splicing variants (SPIDEX) were used for in silico prediction. In vitro effects of GCK gene variants on splicing were tested using a minigene expression approach. In vitro effect on splicing was shown for 9 of 20 variants, including two synonymous substitutions. In silico and in vitro results matched in about 50% of cases. The results demonstrate that novel or rare apparently benign GCK gene variants should be regarded as potential splicing mutations.

High frequency of pathogenic and rare sequence variants in diabetes-related genes among Russian patients with diabetes in pregnancy.

AIMS: Diabetes in pregnancy may be associated with monogenic defects of beta-cell function, frequency of which depends on ethnicity, clinical criteria for selection of patients as well as methods used for genetic analysis. The aim was to evaluate the contribution and molecular spectrum of mutations among genes associated with monogenic diabetes in non-obese Russian patients with diabetes in pregnancy using the next-generation sequencing (NGS). METHODS: 188 non-obese pregnant women with diabetes during pregnancy were included in the study; among them 57 subjects (30.3%) met the American Diabetes Association (ADA) criteria of preexisting pregestational diabetes (pre-GDM), whereas 131 women (69.7%) fulfilled criteria of gestational diabetes mellitus (GDM). A custom NGS panel targeting 28 diabetes causative genes was used for sequencing. The sequence variants were rated according to the American College of Medical Genetics and Genomics (ACMG) guidelines. RESULTS: In total, 23 pathogenic, 18 likely pathogenic and 16 variants of uncertain significance were identified in 59/188 patients (31.4%). The majority of variants (38/59) were found in GCK gene. No significant differences in the number of variants among the two study groups (pre-GDM and GDM) were observed. CONCLUSIONS: The study suggests that frequency of monogenic variants of diabetes might be underestimated, which warrants a broader use of genetic testing, especially in pregnancy.

High frequency of mutations in 'dyshormonogenesis genes' in severe congenital hypothyroidism.

OBJECTIVE: Results of the screening of disease causative mutations in congenital hypothyroidism (CH) vary significantly, depending on the sequence strategy, patients' inclusion criteria and bioinformatics. The objective was to study the molecular basis of severe congenital hypothyroidism, using the next generation sequencing (NGS) and the recent guidelines for assessment of sequence variants. DESIGN: 243 patients with CH (TSH levels at neonatal screening or retesting greater than 90 mU/l) and 56 control subjects were included in the study. METHODS: A custom NGS panel targeting 12 CH causative genes was used for sequencing. The sequence variants were rated according to American College of Medical Genetics and Genomics (ACMG) guidelines. RESULTS: In total, 48 pathogenic, 7 likely pathogenic and 57 variants of uncertain significance were identified in 92/243 patients (37.9%), while 4 variants of uncertain significance were found in 4/56 control subjects (7.1%). 13.1% (12/92) of the cases showed variants in 'thyroid dysgenesis' (TD) genes: TSHR, n = 6; NKX2-1, n = 2; NKX2-5, n = 1; PAX8, n = 3. The variants in 'dyshormonogenesis' (DH) genes were found in 84.8% (78/92) of cases: TPO, n = 30; DUOX2, n = 24; TG, n = 8; SLC5A5, n = 3; SLC26A4, n = 6; IYD, n = 1. 8 patients showed oligonenic variants. The majority of variants identified in DH genes were monoallelic. CONCLUSIONS: In contrast to earlier studies demonstrating the predominance of TD in severe CH, the majority of variants identified in our study were in DH genes. A large proportion of monoallelic variants detected among DH genes suggests that non-mendelian mechanisms may play a role in the development of CH.

Primary hyperparathyroidism in young patients in Russia: high frequency of hyperparathyroidism-jaw tumor syndrome.

BACKGROUND: Primary hyperparathyroidism (PHPT) is a relatively rare disorder among children, adolescents and young adults. Its development at an early age is suspicious for hereditary causes, though the need for routine genetic testing remains controversial. OBJECTIVE: To identify and describe hereditary forms of PHPT in patients with manifestation of the disease under 40 years of age. DESIGN: We enrolled 65 patients with PHPT diagnosed before 40 years of age. Ten of them had MEN1 mutation, and PHPT in them was the first manifestation of multiple endocrine neoplasia type 1 syndrome. METHODS: The other fifty-five patients underwent next-generation sequencing (NGS) of a custom-designed panel of genes, associated with PHPT (MEN1, CASR, CDC73, CDKN1A, CDKN1B, CDKN1C, CDKN2A, CDKN2C, CDKN2D). In cases suspicious for gross CDC73 deletions multiplex ligation-dependent probe amplification was performed. RESULTS: NGS revealed six pathogenic or likely pathogenic germline sequence variants: four in CDC73 c.271C>T (p.Arg91*), c.496C>T (p.Gln166*), c.685A>T (p.Arg229*) and c.787C>T (p.Arg263Cys); one in CASR c.3145G>T (p.Glu1049*) and one in MEN1 c.784-9G>A. In two patients, MLPA confirmed gross CDC73 deletions. In total, 44 sporadic and 21 hereditary PHPT cases were identified. Parathyroid carcinomas and atypical parathyroid adenomas were present in 8/65 of young patients, in whom CDC73 mutations were found in 5/8. CONCLUSIONS: Hereditary forms of PHPT can be identified in up to 1/3 of young patients with manifestation of the disease at <40 years of age. Parathyroid carcinomas or atypical parathyroid adenomas in young patients are frequently associated with CDC73 mutations.

Progressive Generalized Lipodystrophy as a Manifestation of Autoimmune Polyglandular Syndrome Type 1.

We describe APS1 in a boy with generalized lipodystrophy, oral candidiasis, autoimmune hepatitis and adrenal insufficiency. It is the first time when generalized lipodystrophy is associated with APS1.

Partial deficiency of 17α-hydroxylase/17,20-lyase caused by a novel missense mutation in the canonical cytochrome heme-interacting motif.

BACKGROUND: Deficiency of 17α-hydroxylase/17,20-lyase is a rare cause of 46,XY disordered sex development. OBJECTIVE: We characterize in vitro and in vivo effects of two novel CYP17A1 gene mutations identified in a patient with a mild phenotype of CYP17A1 deficiency. SUBJECTS AND METHODS: A 46,XY patient presented with ambiguous genitalia. CYP17A1 deficiency was suspected at 2 months on the basis of steroid analysis performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Mutational analysis of the CYP17A1 gene was performed by PCR and Sanger sequencing. To characterize the effect of CYP17A1 mutation on 17α-hydroxylase and 17,20-lyase activities in vitro, HEK293 cells were transiently transfected with CYP17A1 expression plasmids, incubated with progesterone or 17-OH-pregnenolone and concentrations of 17-OH-progesterone or DHEA were then measured in the cell culture medium by LC-MS/MS. RESULTS: Clinical and hormonal findings in the patient were consistent with partial combined deficiency of 17α-hydroxylase/17,20-lyase. The sequencing of the CYP17A1 gene in the patient revealed compound heterozygosity for two novel mutations: c.107delT p.R36fsX107 and p.W121R. After 6-h in vitro culture of transfected HEK293 cells in the presence of 1 µM progesterone, 17α-hydroxylase activity of p.W121R mutant was 60.5±16.3%, while 17,20-lyase activity of mutant measured from the amount of DHEA produced in the presence of 1 µM of 17-OH-pregnenolone was 15.8±2.6% compared with the WT. CONCLUSIONS: p.W121R substitution, affecting the first residue in the conserved heme-interacting WXXXR motif of CYP17A1, is associated with partial combined deficiency of 17α-hydroxylase/17,20-lyase.