Nicotinic Signaling Stimulates Glucagon Secretion in Mouse and Human Pancreatic α-Cells.

Smoking is widely regarded as a risk factor for type 2 diabetes because nicotine contributes to insulin resistance by desensitizing the insulin receptors in muscle, liver, or fat. Little is known, however, about the immediate regulation of islet hormonal output by nicotine, an agonist of ionotropic cholinergic receptors. We investigated this by imaging cytosolic Ca2+ dynamics in mouse and human islets using confocal microscopy and measuring glucagon secretion in response to the alkaloid from isolated mouse islets.

Molecular and Clinical Features of Pancreatic Acinar Cell Carcinoma: A Single-Institution Case Series.

Acinar cell carcinoma (ACC) accounts for about 1% of pancreatic cancers. The molecular and clinical features of ACC are less characterized than those of pancreatic ductal adenocarcinoma. : We retrospectively evaluated the clinical and molecular features of ACC patients who underwent germline and/or somatic molecular testing at The University of Texas MD Anderson Cancer Center from 2008 to 2022 and two cases from 2023-2024 who underwent RNA and TME analysis by Boston Gene.

Loss of electrical β-cell to δ-cell coupling underlies impaired hypoglycaemia-induced glucagon secretion in type-1 diabetes.

Diabetes mellitus involves both insufficient insulin secretion and dysregulation of glucagon secretion. In healthy people, a fall in plasma glucose stimulates glucagon release and thereby increases counter-regulatory hepatic glucose production. This response is absent in many patients with type-1 diabetes (T1D), which predisposes to severe hypoglycaemia that may be fatal and accounts for up to 10% of the mortality in patients with T1D.

Cafeteria diet compromises natural adaptations of islet cell transdifferentiation and turnover in pregnancy.

Background: Pancreatic islet β-cell mass expands during pregnancy, but underlying mechanisms are not fully understood. This study examines the impact of pregnancy and cafeteria diet on islet morphology, associated cellular proliferation/apoptosis rates as well as β-cell lineage.

Methods: Non-pregnant and pregnant Ins1;Rosa26-eYFP transgenic mice were maintained on either normal or high-fat cafeteria diet, with pancreatic tissue obtained at 18 days gestation.

Influence of the Structure of Hydrothermal-Synthesized TiO Nanowires Formed by Annealing on the Photocatalytic Reduction of CO in HO Vapor.

The present study investigates the photocatalytic properties of hydrothermally synthesized TiO nanowires (NWs) for CO reduction in HO vapor. It has been demonstrated that TiO NWs, thermally treated at 500-700 °C, demonstrate an almost tenfold higher yield of products compared to the known commercial powder TiO P25. It has been found that the best material is a combination of anatase, TiO-B and rutile.

[P]PP, a stable, long-acting pancreatic polypeptide analogue, evokes weight lowering and pancreatic beta-cell-protective effects in obesity-associated diabetes.

Aim: To thoroughly investigate the impact of sustained neuropeptide Y4 receptor (NPY4R) activation in obesity-associated diabetes.

Methods: Initially, the prolonged pharmacodynamic profile of the enzymatically stable pancreatic polypeptide (PP) analogue, [P]PP, was confirmed in normal mice up to 24 h after injection. Subsequent to this, [P]PP was administered twice daily (25 nmol/kg) for 28 days to high-fat-fed mice with streptozotocin-induced insulin deficiency, known as HFF/STZ mice.

Precursors consumption preferences and thiol release capacity of the wine yeasts Saccharomyces cerevisiae, Torulaspora delbrueckii, and Lachancea thermotolerans.

The aromatic profile of wine determines its overall final quality, and among the volatile molecules that define it, varietal thiols are responsible for shaping the distinctive character of certain wine varieties. In grape must, these thiols are conjugated to amino acids or small peptides in a non-volatile form. During wine fermentation, yeasts play a principal role in expressing these aromatic compounds as they internalise and cleavage these precursors, releasing the corresponding free and aroma-impacting fraction.

The impact of GLP-1 signalling on the energy metabolism of pancreatic islet β-cells and extrapancreatic tissues.

Glucagon-like peptide-1 signalling impacts glucose homeostasis and appetite thereby indirectly affecting substrate availability at the whole-body level. The incretin canonically produces an insulinotropic effect, thereby lowering blood glucose levels by promoting the uptake and inhibiting the production of the sugar by peripheral tissues. Likewise, GLP-1 signalling within the central nervous system reduces the appetite and food intake, whereas its gastric effect delays the absorption of nutrients, thus improving glycaemic control and reducing the risk of postprandial hyperglycaemia.

Dopamine signalling in pancreatic islet cells and role in adaptations to metabolic stress.

Objectives: Dopamine and related receptors are evidenced in pancreatic endocrine tissue, but the impact on islet β-cell stimulus-secretion as well as (patho)physiological role are unclear.

Methods: The present study has evaluated islet cell signalling pathways and biological effects of dopamine, as well as alterations of islet dopamine in rodent models of diabetes of different aetiology.

Key Findings: The dopamine precursor l-DOPA partially impaired glucose tolerance in mice and attenuated glucose-, exendin-4, and alanine-induced insulin secretion.

The endoplasmic reticulum plays a key role in α-cell intracellular Ca dynamics and glucose-regulated glucagon secretion in mouse islets.

Glucagon is secreted by pancreatic α-cells to counteract hypoglycaemia. How glucose regulates glucagon secretion remains unclear. Here, using mouse islets, we studied the role of transmembrane and endoplasmic reticulum (ER) Ca on intrinsic α-cell glucagon secretion.

Estimation of phase distortions of the photoplethysmographic signal in digital IIR filtering.

Pre-processing of the photoplethysmography (PPG) signal plays an important role in the analysis of the pulse wave signal. The task of pre-processing is to remove noise from the PPG signal, as well as to transmit the signal without any distortions for further analysis. The integrity of the pulse waveform is essential since many cardiovascular parameters are calculated from it using morphological analysis.

Molecular determinants and intracellular targets of taurine signalling in pancreatic islet β-cells.

Aim: Despite its abundance in pancreatic islets of Langerhans and proven antihyperglycemic effects, the impact of the essential amino acid, taurine, on islet β-cell biology has not yet received due consideration, which prompted the current studies exploring the molecular selectivity of taurine import into β-cells and its acute and chronic intracellular interactions.

Methods: The molecular aspects of taurine transport were probed by exposing the clonal pancreatic BRIN BD11 β-cells and primary mouse and human islets to a range of the homologs of the amino acid (assayed at 2-20 mM), using the hormone release and imaging of intracellular signals as surrogate read-outs. Known secretagogues were employed to profile the interaction of taurine with acute and chronic intracellular signals.

Optical and scintillation properties of hybrid manganese(II) bromides with formamidinium and acetamidinium cations.

In recent years, hybrid manganese(II) halides (HMHs) have attracted wide attention due to their impressive optical properties, low toxicity, and facile synthetic processibility. Being effective reabsorption-free phosphors, these compounds demonstrate the potential to be used as low-cost solution-processable scintillators. However, most of the HMHs studied to date contain bulk organic cations and, as a result, are characterized by low density and low X-ray stopping power.

Taxonomic diversity and abundance of enchytraeids (Annelida, Clitellata, Enchytraeida) in the Northern Palaearctic. 1. Asian part.

Background: Enchytraeids, or potworms, are tiny oligochaetes that are distributed worldwide in many terrestrial, freshwater and marine ecosystems. Despite their key role in the functioning of ecosystems, the diversity and abundance of Enchytraeidae are rarely studied due to the laborious process of species identification. The present study addresses this gap and sheds some light on the distribution and abundance of enchytraeids in the lands of the Northern Palearctic.

GLP-1 metabolite GLP-1(9-36) is a systemic inhibitor of mouse and human pancreatic islet glucagon secretion.

Aims/hypothesis: Diabetes mellitus is associated with impaired insulin secretion, often aggravated by oversecretion of glucagon. Therapeutic interventions should ideally correct both defects. Glucagon-like peptide 1 (GLP-1) has this capability but exactly how it exerts its glucagonostatic effect remains obscure.

Insight into the electronic structure of the centrosymmetric skyrmion magnet GdRuSi.

The discovery of a square magnetic-skyrmion lattice in GdRuSi, with the smallest so far found skyrmion size and without a geometrically frustrated lattice, has attracted significant attention. In this work, we present a comprehensive study of surface and bulk electronic structures of GdRuSi by utilizing momentum-resolved photoemission (ARPES) measurements and first-principles calculations. We show how the electronic structure evolves during the antiferromagnetic transition when a peculiar helical order of 4f magnetic moments within the Gd layers sets in.

Protease detection in the biosensor era: A review.

Proteases have been proposed as potential biomarkers for several pathological conditions including cancers, multiple sclerosis and cardiovascular diseases, due to their ability to break down the components of extracellular matrix and basement membrane. The development of protease biosensors opened up the possibility to investigate the proteolytic activity of dysregulated proteases with higher efficiency over the traditional detection assays due to their quick detection capability, high sensitivity and selectivity, simple instrumentation and cost-effective fabrication processes. In contrast to the recently published review papers that primarily focused on one specific class of proteases or one specific detection method, this review article presents different optical and electrochemical detection methods that can be used to design biosensors for all major protease families.

Pancreatic islet cell plasticity: Pathogenic or therapeutically exploitable?

The development of pancreatic islet endocrine cells is a tightly regulated process leading to the generation of distinct cell types harbouring different hormones in response to small changes in environmental stimuli. Cell differentiation is driven by transcription factors that are also critical for the maintenance of the mature islet cell phenotype. Alteration of the insulin-secreting β-cell transcription factor set by prolonged metabolic stress, associated with the pathogenesis of diabetes, obesity or pregnancy, results in the loss of β-cell identity through de- or transdifferentiation.

Topological phase transition in the antiferromagnetic topological insulator MnBi[Formula: see text]Te[Formula: see text] from the point of view of axion-like state realization.

This work aims to study the conditions of topological phase transition (TPT) between the topological and trivial states in the antiferromagnetic topological insulator (AFM TI) MnBi[Formula: see text]Te[Formula: see text] and propose some theory about the relationship of this TPT with the possibility of axion-like state realization in this material. Using the density functional approach we have analyzed the changes in the electronic and spin structure of topological surface states (TSSs) and the nearest conduction and valence bands (CB and VB) including the changes in the bulk band gap as well as the Dirac point (DP) gap in TSSs under variation of the spin-orbit coupling strength in the region of the TPT for infinite crystal and slab with a surface both. We have shown that in both cases the TPT occurs with inversion of the contributions of the Bi-[Formula: see text] and Te-[Formula: see text] states of different parity at the gap edges related to change in the gap sign.

Evolution of MnGeBiTe Electronic Structure under Variation of Ge Content.

One of the approaches to manipulate MnBi2Te4 properties is the magnetic dilution, which inevitably affects the interplay of magnetism and band topology in the system. In this work, we carried out angle-resolved photoemission spectroscopy (ARPES) measurements and density functional theory (DFT) calculations for analysing changes in the electronic structure of Mn1-xGexBi2Te4 that occur under parameter x variation. We consider two ways of Mn/Ge substitution: (i) bulk doping of the whole system; (ii) surface doping of the first septuple layer.

The Composite TiO-CuO Layers Formed by Electrophoretic Method for CO Gas Photoreduction.

This study demonstrates the ability to control the properties of TiO-CuO composite layers for photocatalytic applications by using a simple electrophoretic deposition method from isopropanol-based suspension. To obtain uniform layers with a controlled composition, the surfactant sodium lauryl sulfate was used, which influenced the electrophoretic mobility of the particles and the morphology of the deposited layers. The TiO-CuO composite layers with different CuO contents (1.

Anxiety, Stress Perception, and Coping Strategies among Students with COVID-19 Exposure.

: Studying anxiety, stress, and coping strategies during the COVID-19 pandemic is crucial to mitigate the negative effects associated with infection risk and disease consequences. : This study aimed to investigate anxiety levels, stress perception, and coping strategies in relation to the presence of illness. : A cross-sectional online survey was conducted anonymously among 3950 university students from Poland (1822), Lithuania (232), and the Russian exclave of Kaliningrad (1896).

Highly sensitive voltammetric determination of Allura Red (E129) food colourant on a planar carbon fiber sensor modified with shungite.

This article presents an original planar carbon fiber electrode (PCFE), in which shungite (SHU) is used as a modifier for the first time. Shungite is a unique natural nanostructured composite consisting of carbon in the form of aggregated graphene stacks, oxides of silicon, titanium, aluminum, iron, magnesium, potassium, etc. Macro- and micro-elements, biologically active components that are present in shungite provide it with attractive antioxidant properties, make it a biocompatible and environmentally friendly material that meets the principles of green chemistry.