Purpose: The use of laparoscopic surgery for colorectal cancer in elderly patients with high comorbidity is a controversial subject. This retrospective analysis aims to compare two different age groups with respect to short and long term clinical and oncological outcomes.
Methods: All laparoscopic colorectal resections for cancer performed between February 2011 and October 2017 with curative or palliative intention were evaluated.
Front Endocrinol (Lausanne)
May 2021
Objective: Congenital hyperinsulinism (CHI) is a rare disease characterized by persistent hypoglycemia as a result of inappropriate insulin secretion, which can lead to irreversible neurological defects in infants. Poor efficacy and strong adverse effects of the current medications impede successful treatment. The aim of the study was to investigate new approaches to silence β-cells and thus attenuate insulin secretion.
View Article and Find Full Text PDFThe aim for this study was to elucidate how the hypothalamic hunger-inducing hormone acyl-ghrelin (AG), which is also produced in the pancreas, affects β-cell function, with particular attention to the role of ATP-sensitive K (K) channels and the exact site of action of the hormone. AG hyperpolarized the membrane potential and decreased cytoplasmic calcium concentration [Ca] and glucose-stimulated insulin secretion (GSIS). These effects were abolished in β-cells from SUR1-knockout (KO) mice.
View Article and Find Full Text PDFNovel agonists of the nuclear liver-X-receptor (LXR) are designed to treat metabolic disorders or cancer. The rationale to develop these new drugs is based on promising results with established LXR agonist like T0901317 and GW3965. LXRα and LXRβ are expressed in β-cells, and expression is increased by T0901317.
View Article and Find Full Text PDFBile acids such as chenodeoxycholic acid (CDC) acutely enhance insulin secretion via the farnesoid X receptor (FXR). Statins, which are frequently prescribed for patients with type 2 diabetes who suffer from dyslipidemia, are known for their diabetogenic risk and are reported to interact with the FXR. Our study investigates whether this interaction is relevant for beta cell signaling and plays a role for negative effects of statins on glycemic control.
View Article and Find Full Text PDFNon-invasive imaging of β-cells represents a desirable preclinical and clinical tool to monitor the change of β-cell mass and the loss of function during pre-diabetic stages. Although it is widely accepted that manganese (Mn) ions are actively gated by voltage-dependent calcium channels (VDCC) in response to glucose metabolism, little is known on its specificity for quantification of islet β-cell function using Mn and magnetic resonance imaging (MRI). On the other hand, glucagon-like-peptide-1 receptor (GLP-1R) represents a validated target for the estimation of β-cell mass using radiolabeled exendin-4 (Ex4) and positron emission tomography (PET).
View Article and Find Full Text PDFGlucose-stimulated insulin secretion (GSIS) is the gold standard for β-cell function. Both experimental and clinical diabetology, i. e.
View Article and Find Full Text PDFBiosensors have emerged as a valuable tool with high specificity and sensitivity for fast and reliable detection of hazardous substances in drinking water. Numerous substances have been addressed using synthetic biology approaches. However, many proposed biosensors are based on living, genetically modified organisms and are therefore limited in shelf life, usability and biosafety.
View Article and Find Full Text PDFNeuroendocrine-type ATP-sensitive K (K) channels are metabolite sensors coupling membrane potential with metabolism, thereby linking insulin secretion to plasma glucose levels. They are octameric complexes, (SUR1/Kir6.2), comprising sulfonylurea receptor 1 (SUR1 or ABCC8) and a K-selective inward rectifier (Kir6.
View Article and Find Full Text PDFThe Takeda-G-protein-receptor-5 (TGR5) mediates physiological actions of bile acids. Since it was shown that TGR5 is expressed in pancreatic tissue, a direct TGR5 activation in β-cells is currently postulated and discussed. The current study reveals that oleanolic acid (OLA) affects murine β-cell function by TGR5 activation.
View Article and Find Full Text PDFDevelopment of the cereal endosperm involves cell differentiation processes that enable nutrient uptake from the maternal plant, accumulation of storage products, and their utilization during germination. However, little is known about the regulatory mechanisms that link cell differentiation processes with those controlling storage product synthesis and deposition, including the activation of zein genes by the maize () bZIP transcription factor Opaque-2 (O2). Here, we mapped in vivo binding sites of O2 in B73 endosperm and compared the results with genes differentially expressed in B73 and B73 We identified 186 putative direct O2 targets and 1677 indirect targets, encoding a broad set of gene functionalities.
View Article and Find Full Text PDFPurpose: The role of ATP, which is secreted by pancreatic β-cells, is still a matter of debate. It has been postulated that extracellular ATP acts as a positive auto- or paracrine signal in β-cells amplifying insulin secretion. However, there is rising evidence that extracellular ATP may also mediate a negative signal.
View Article and Find Full Text PDFEarly endosperm development presents a unique system in which to uncover epigenetic regulatory mechanisms because the contributing maternal and paternal genomes possess differential epigenetic modifications. In Arabidopsis (), the initiation of endosperm coenocytic growth upon fertilization and the transition to endosperm cellularization are regulated by the FERTILIZATION-INDEPENDENT SEED (FIS)-Polycomb Repressive Complex 2 (PRC2), a putative H3K27 methyltransferase. Here, we address the possible role of the FIS-PRC2 complex in regulating the type I MADS-box gene family, which has been shown previously to regulate early endosperm development.
View Article and Find Full Text PDFWe have shown previously that genetic or pharmacological deletion of K channels protect against beta cell dysfunction induced by reactive oxygen species (ROS). Since it is assumed that glucolipotoxicity (GLTx) causes ROS production, we aimed to evaluate whether suppression of K channel activity can also prevent beta cell damage evoked by GLTx. We used an in vitro model of GLTx and measured distinct parameters of stimulus-secretion coupling.
View Article and Find Full Text PDFAtrial natriuretic peptide (ANP) influences glucose homeostasis and possibly acts as a link between the cardiovascular system and metabolism, especially in metabolic disorders like diabetes. The current study evaluated effects of ANP on β-cell function by the use of a β-cell-specific knockout of the ANP receptor with guanylate cyclase activity (βGC-A-KO). ANP augmented insulin secretion at the threshold glucose concentration of 6 mmol/L and decreased K single-channel activity in β-cells of control mice but not of βGC-A-KO mice.
View Article and Find Full Text PDFThe role of liver X receptor (LXR) in pancreatic β-cell physiology and pathophysiology is still unclear. It has been postulated that chronic LXR activation in β-cells induces lipotoxicity, a key step in the development of β-cell dysfunction, which accompanies type 2 diabetes mellitus. In most of these studies, the LXR ligand T0901317 has been administered chronically in the micromolar range to study the significance of LXR activation.
View Article and Find Full Text PDFThe EGG CELL1 (EC1) gene family of Arabidopsis (Arabidopsis thaliana) comprises five members that are specifically expressed in the egg cell and redundantly control gamete fusion during double fertilization. We investigated the activity of all five EC1 promoters in promoter-deletion studies and identified SUF4 (SUPPRESSOR OF FRIGIDA4), a CH transcription factor, as a direct regulator of the EC1 gene expression. In particular, we demonstrated that SUF4 binds to all five Arabidopsis EC1 promoters, thus regulating their expression.
View Article and Find Full Text PDFZentralbl Chir
October 2016
The gastrooesophageal reflux disease (GERD) is a possible cause of chronic cough. The laparoscopic fundoplication is well established in the treatment of GERD. In a retrospective study, the effectivity of this operation on the GERD associated cough was examined and possible preoperative predictive factors concerning the post-surgical therapy effect were characterized.
View Article and Find Full Text PDFThe angiotensin-converting enzyme 2/angiotensin (Ang)-(1-7)/Mas axis of the renin-angiotensin system often opposes the detrimental effects of the angiotensin-converting enzyme/Ang II/Ang II type 1 receptor axis and has been associated with beneficial effects on glucose homeostasis, whereas underlying mechanisms are mostly unknown. Here we investigate the effects of Ang-(1-7) and its receptor Mas on β-cell function. Isolated islets from Mas-deficient and wild-type mice were stimulated with Ang-(1-7) or its antagonists and effects on insulin secretion determined.
View Article and Find Full Text PDFPancreatic beta-cells respond to an unchanging stimulatory glucose concentration with oscillations in membrane potential (Vm), cytosolic Ca(2+) concentration ([Ca(2+)]c), and insulin secretion. The underlying mechanisms are largely ascertained. Some particular details, however, are still in debate.
View Article and Find Full Text PDFAims/hypothesis: Generation of reduction equivalents is a prerequisite for nutrient-stimulated insulin secretion. Mitochondrial succinate dehydrogenase (SDH) fulfils a dual function with respect to mitochondrial energy supply: (1) the enzyme is part of mitochondrial respiratory chains; and (2) it catalyses oxidation of succinate to fumarate in the Krebs cycle. The aim of our study was to elucidate the significance of SDH for beta cell stimulus-secretion coupling (SSC).
View Article and Find Full Text PDFExp Clin Endocrinol Diabetes
May 2015
This study demonstrates for the first time that the microelectrode array (MEA) technique allows analysis of electrical activity of islets isolated from human biopsies. We have shown before that this method, i.e.
View Article and Find Full Text PDFEndosperm is an absorptive structure that supports embryo development or seedling germination in angiosperms. The endosperm of cereals is a main source of food, feed, and industrial raw materials worldwide. However, the genetic networks that regulate endosperm cell differentiation remain largely unclear.
View Article and Find Full Text PDFWe have recently shown that the bile acid (BA) taurochenodeoxycholate (TCDC) acutely stimulates insulin secretion via activation of the farnesoid X receptor (FXR). Aims of the current investigation were to discriminate between nongenomic (≤1 h) and genomic effects (24-48 h) of BAs on β-cells and to evaluate whether FXR can modulate the adverse effects of a high-fat diet (HFD). TCDC (500 nM) as well as glycine-conjugated and unconjugated CDC (chenodeoxycholate) increased insulin secretion in acute incubations but did not evoke additional effects after 1-2 days of preincubation.
View Article and Find Full Text PDFEndosperm is a filial structure resulting from a second fertilization event in angiosperms. As an absorptive storage organ, endosperm plays an essential role in support of embryo development and seedling germination. The accumulation of carbohydrate and protein storage products in cereal endosperm provides humanity with a major portion of its food, feed, and renewable resources.
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