Prevalence of Staphylococcus aureus in wild hedgehogs (Erinaceus europaeus) and first report of mecC-MRSA in Hungary.

In 2011 mecC, a new mecA gene homologue, was described in a bovine isolate in the UK. Since then, mecC-positive methicillin-resistant Staphylococcus aureus (mecC-MRSA) has also been found in wild animals. An especially high prevalence of mecC-MRSA has been reported among hedgehogs in Sweden (64%) and Denmark (61%).

Bicarbonate Evokes Reciprocal Changes in Intracellular Cyclic di-GMP and Cyclic AMP Levels in .

The formation of Pseudomonas aeruginosa biofilms in cystic fibrosis (CF) is one of the most common causes of morbidity and mortality in CF patients. Cyclic di-GMP and cyclic AMP are second messengers regulating the bacterial lifestyle transition in response to environmental signals. We aimed to investigate the effects of extracellular pH and bicarbonate on intracellular c-di-GMP and cAMP levels, and on biofilm formation.

Three-Dimensional Culture of Ameloblast-Originated HAT-7 Cells for Functional Modeling of Defective Tooth Enamel Formation.

Amelogenesis, the formation of dental enamel, is well understood at the histomorphological level but the underlying molecular mechanisms are poorly characterized. Ameloblasts secrete enamel matrix proteins and Ca, and also regulate extracellular pH as the formation of hydroxyapatite crystals generates large quantities of protons. Genetic or environmental impairment of transport and regulatory processes (e.

TRPM7-Mediated Calcium Transport in HAT-7 Ameloblasts.

TRPM7 plays an important role in cellular Ca, Zn and Mg homeostasis. TRPM7 channels are abundantly expressed in ameloblasts and, in the absence of TRPM7, dental enamel is hypomineralized. The potential role of TRPM7 channels in Ca transport during amelogenesis was investigated in the HAT-7 rat ameloblast cell line.

STRO-1 positive cell expansion during osteogenic differentiation: A comparative study of three mesenchymal stem cell types of dental origin.

Objective: Although the osteogenic differentiation potential of mesenchymal stem cells of dental origin is well established, the roles of different marker proteins in this process remain to be clarified. Our aim was to compare the cellular and molecular changes, focusing in particular on mesenchymal stem cell markers, during in vitro osteogenesis in three dental stem cell types: dental follicle stem cells (DFSCs), periodontal ligament stem cells (PDLSCs) and dental pulp stem cells (DPSCs).

Design: Human DFSCs, PDLSCs and DPSCs were isolated, cultured and their osteogenic differentiation was induced for 3 weeks.

Saliva as a Candidate for COVID-19 Diagnostic Testing: A Meta-Analysis.

COVID-19 is a serious and potentially deadly disease. Early diagnosis of infected individuals will play an important role in stopping its further escalation. The present gold standard for sampling is the nasopharyngeal swab method.

Author Correction: Organic osmolytes preserve the function of the developing tight junction in ultraviolet B-irradiated rat epidermal keratinocytes.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Organic osmolytes preserve the function of the developing tight junction in ultraviolet B-irradiated rat epidermal keratinocytes.

Epidermal barrier function is provided by the highly keratinised stratum corneum and also by tight junctions (TJs) in the granular layer of skin. The development of the TJ barrier significantly deteriorates in response to ultraviolet B radiation (UVB). Following exposure to UVB, keratinocytes accumulate organic osmolytes, which are known to preserve cell volume during water stress.

No Change in Bicarbonate Transport but Tight-Junction Formation Is Delayed by Fluoride in a Novel Ameloblast Model.

We have recently developed a novel model using HAT-7 rat ameloblast cells to functionally study epithelial ion transport during amelogenesis. Our present aims were to identify key transporters of bicarbonate in HAT-7 cells and also to examine the effects of fluoride exposure on vectorial bicarbonate transport, cell viability, and the development of transepithelial resistance. To obtain monolayers, the HAT-7 cells were cultured on Transwell permeable filters.

Bicarbonate-rich fluid secretion predicted by a computational model of guinea-pig pancreatic duct epithelium.

Key Points: The ductal system of the pancreas secretes large volumes of alkaline fluid containing HCO concentrations as high as 140 mm during hormonal stimulation. A computational model has been constructed to explore the underlying ion transport mechanisms. Parameters were estimated by fitting the model to experimental data from guinea-pig pancreatic ducts.

Evidence for Active Electrolyte Transport by Two-Dimensional Monolayers of Human Salivary Epithelial Cells.

Functional reconstruction of lost tissue by regenerative therapy of salivary glands would be of immense benefit following radiotherapy or in the treatment of Sjogren's syndrome. The purpose of this study was to develop primary cultures of human salivary gland cells as potential regenerative resources and to characterize their acinar/ductal phenotype using electrophysiological measurements of ion transport. Human salivary gland cultures were prepared either from adherent submandibular gland cells (huSMG) or from mixed adherent and nonadherent cells (PTHSG) and were cultivated in Hepato-STIM or minimum essential medium (MEM).

Pathophysiologic Changes in Extracellular pH Modulate Parathyroid Calcium-Sensing Receptor Activity and Secretion via a Histidine-Independent Mechanism.

The calcium-sensing receptor (CaR) modulates renal calcium reabsorption and parathyroid hormone (PTH) secretion and is involved in the etiology of secondary hyperparathyroidism in CKD. Supraphysiologic changes in extracellular pH (pHo) modulate CaR responsiveness in HEK-293 (CaR-HEK) cells. Therefore, because acidosis and alkalosis are associated with altered PTH secretion in vivo, we examined whether pathophysiologic changes in pHo can significantly alter CaR responsiveness in both heterologous and endogenous expression systems and whether this affects PTH secretion.

Role of organic osmolytes in water homoeostasis in skin.

The ability to conserve water is fundamental to terrestrial life. A number of organs such as the kidney and the bladder have important roles in the regulation of body water balance. The epidermis of skin is also fundamental to this process, and it is in a constant battle to prevent loss of water to the external, dry environment.

Role of anion exchangers in Cl- and HCO3- secretion by the human airway epithelial cell line Calu-3.

Despite the importance of airway surface liquid pH in the lung's defenses against infection, the mechanism of airway HCO3- secretion remains unclear. Our aim was to assess the contribution of apical and basolateral Cl-/HCO3- exchangers to Cl- and HCO3- transport in the Calu-3 cell line, derived from human airway submucosal glands. Changes in intracellular pH (pHi) were measured following substitution of Cl- with gluconate.

Deletion of Slc26a6 alters the stoichiometry of apical Cl-/HCO-3 exchange in mouse pancreatic duct.

To define the stoichiometry and molecular identity of the Cl(-)/HCO(3)(-) exchanger in the apical membrane of pancreatic duct cells, changes in luminal pH and volume were measured simultaneously in interlobular pancreatic ducts isolated from wild-type and Slc26a6-null mice. Transepithelial fluxes of HCO(3)(-) and Cl(-) were measured in the presence of anion gradients favoring rapid exchange of intracellular HCO(3)(-) with luminal Cl(-) in cAMP-stimulated ducts. The flux ratio of Cl(-) absorption/HCO(3)(-) secretion was ∼0.

High glucose inhibits HCO3(-) and fluid secretion in rat pancreatic ducts.

Cellular mechanisms underlying the impairment of pancreatic fluid and electrolyte secretion in diabetes were examined using interlobular ducts isolated from rat pancreas. Fluid secretion was assessed by monitoring changes in luminal volume. HCO3(-) uptake across the basolateral membrane was estimated from the recovery of intracellular pH following an acid load.

Bicarbonate transport by the human pancreatic ductal cell line HPAF.

Objectives: The human pancreatic duct cell line, HPAF, has been shown previously to secrete Cl(-) in response to Ca(2+)-mobilizing stimuli. Our aim was to assess the capacity of HPAF cells to transport and secrete HCO3(-).

Methods: HPAF cells were grown as confluent monolayers on permeable supports.

Ducts isolated from the pancreas of CFTR-null mice secrete fluid.

The pancreatic pathology in cystic fibrosis (CF) is normally attributed to the failure of ductal fluid secretion resulting from the lack of functional CF transmembrane conductance regulator (CFTR). However, murine models of CF show little or no pancreatic pathology. To resolve this dichotomy we analysed the transport mechanisms involved in fluid and electrolyte secretion by pancreatic ducts isolated from CFTR-null mice.

Molecular and cellular regulation of pancreatic duct cell function.

Purpose Of Review: The pancreatic duct epithelium is remarkable for its capacity to secrete HCO(3)(-) ions at concentrations as high as 140 mmol/l. The properties of the key transporters involved in this process and the central role played by cystic fibrosis transmembrane conductance regulator (CFTR) are the main focus of this review.

Recent Findings: The Cl(-)/HCO(3)(-) exchanger at the apical membrane of pancreatic duct cells is now known to be SLC26A6.

CFTR functions as a bicarbonate channel in pancreatic duct cells.

Pancreatic duct epithelium secretes a HCO(3)(-)-rich fluid by a mechanism dependent on cystic fibrosis transmembrane conductance regulator (CFTR) in the apical membrane. However, the exact role of CFTR remains unclear. One possibility is that the HCO(3)(-) permeability of CFTR provides a pathway for apical HCO(3)(-) efflux during maximal secretion.

The role of CFTR in bicarbonate secretion by pancreatic duct and airway epithelia.

The secretory epithelia of the pancreatic duct and airway share the ability to generate HCO(3)(-)-rich fluids. They both express CFTR (cystic fibrosis transmembrane conductance regulator) at the apical membrane and both are adversely affected by cystic fibrosis. CFTR is predominantly a Cl(-) channel, and it is widely believed that HCO(3)(-) secretion in the pancreatic duct is mediated mainly by a Cl(-)/HCO(3)(-) exchanger at the apical membrane.

Glucose transport in interlobular ducts isolated from rat pancreas.

Pancreatic duct cells express Na(+)-dependent glucose transporter, SGLT1 and Na(+)-independent glucose transporters, GLUT1, GLUT2, and GLUT8. We examined transepithelial glucose transport by pancreatic duct. Interlobular ducts were isolated from rat pancreas.

Extracellular calcium- and magnesium-mediated regulation of passive calcium transport across Caco-2 monolayers.

The calcium-sensing receptor (CaR) is expressed on intestinal epithelial serosal membrane and in Caco-2 cells. In renal epithelium, CaR expressed on the basolateral membrane acts to limit excess tubular Ca2+ reabsorption. Therefore, here we investigated whether extracellular calcium (Ca(o)2+) can regulate active or passive 45Ca2+ transport across differentiated Caco-2 monolayers via CaR-dependent or CaR-independent mechanisms.

Vectorial bicarbonate transport by Capan-1 cells: a model for human pancreatic ductal secretion.

Human pancreatic ducts secrete a bicarbonate-rich fluid but our knowledge of the secretory process is based mainly on studies of animal models. Our aim was to determine whether the HCO(3)(-) transport mechanisms in a human ductal cell line are similar to those previously identified in guinea-pig pancreatic ducts. Intracellular pH was measured by microfluorometry in Capan-1 cell monolayers grown on permeable filters and loaded with BCECF.

Mechanisms of bicarbonate secretion in the pancreatic duct.

In many species the pancreatic duct epithelium secretes HCO3- ions at a concentration of around 140 mM by a mechanism that is only partially understood. We know that HCO3- uptake at the basolateral membrane is achieved by Na+-HCO3- cotransport and also by a H+-ATPase and Na+/H+ exchanger operating together with carbonic anhydrase. At the apical membrane, the secretion of moderate concentrations of HCO3- can be explained by the parallel activity of a Cl-/HCO3- exchanger and a Cl- conductance, either the cystic fibrosis transmembrane conductance regulator (CFTR) or a Ca2+-activated Cl- channel (CaCC).