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Sphingomyelin, glycosphingolipids, and ceramide signalling in cells exposed to p-fimbriated Escherichia coli

Uropathogenic Escherichia coli attach to epithelial cells through P fimbriae that bind Galα1‐4Galβ‐oligosaccharide sequences in cell surface glycosphingolipids. The binding of P‐fimbriated E. coli to uroepithelial cells causes the release of ceramide, activation of the ceramide signalling pathway and a cytokine response in the epithelial cells. The present study examined the molecular source of ce

Effects of ursodeoxycholate and other bile salts on the levels of rat intestinal alkaline sphingomyelinase: A potential implication in tumorigenesis

Previous studies showed that bile salts had apromoting effect on colon cancer development and thiseffect was inhibited by ursodeoxycholate (UDC). Werecently found that both human colorectal adenomas and carcinomas were associated with a specificdecrease in alkaline sphingomyelinase activity. In thiswork, we compared the effects of ursodeoxycholate andother bile salts on the levels of rat intestina

Ursodeoxycholic acid increases the activities of alkaline sphingomyelinase and caspase-3 in the rat colon.

BACKGROUND:Ursodeoxycholic acid (UDCA) has been found to inhibit the development of colon carcinoma induced by chemical carcinogens with unidentified mechanisms. Sphingomyelin metabolism has emerged as a novel signal transduction pathway closely related to cell proliferation and apoptosis. We recently found that alkaline sphingomyelinase (SMase) activity was decreased in human colon cancer. The pr

Sphingolipid hydrolysis enzymes in the gastrointestinal tract

In the intestinal tract, there are enzymes that hydrolyze both endogenous and exogenous sphingolipids. The alkaline sphingomyelinases (SMase) of the gut and human bile have been most studied, and a major part of this chapter discusses these enzymes. It also discusses studies of ceramidase, glycosylceramidase, and the digestion of dietary sphingolipids. In the intestinal tract, a distinct enzyme th

A high-beef diet alter protein kinase C isozyme expression in rat colonic mucosa.

We recently reported that a red meat (beef) diet relative to a casein-based diet increases protein kinase C (PKC) activity in rat colonic mucosa. The purpose of this study was to further elucidate the effects of a high-beef diet on colonic intracellular signal transduction by analyzing steady-state protein levels of different PKC isozymes as well as activities of the three types of sphingomyelinas

A mutual inhibitory effect on absorption of sphingomyelin and cholesterol

Several studies have shown that there is a strong physical interaction between cholesterol and sphingomyelin (SM). The critical factor is thought to be the high degree of saturation in the very long acyl chains of SM. In this study we examined the effects of SM on cholesterol absorption in the rat and compared them with those of phosphatidylcholine (PC). Cholesterol absorption was studied by use o

Effects of phospholipids on sphingomyelin hydrolysis induced by intestinal alkaline sphingomyelinase: an in vitro study

Digestion of dietary sphingomyelin (SM) is catalyzed by intestinal alkaline sphingomyelinase (SMase) and may have important implications in colonic tumorigenesis. Previous studies demonstrated that the digestion and absorption of dietary SM was slow and incomplete and that the colon was exposed to SM and its hydrolytic products including ceramide. In the present work, we studied the influences of

Evidence for specific ceramidase present in the intestinal contents of rats and humans.

A neutral ceramidase activity stimulated by bile salt was previously identified in the intestinal content. Recently, bile salt stimulated lipase (BSSL) was found to have ceramidase activity. It is unknown whether the ceramidase activity previously found is attributable to BSSL. To address this question, we compared the behaviors of high quaternary aminoethyl (HQ) anion exchange chromatography, the

Distribution and properties of neutral ceramidase activity in rat intestinal tract

Ceramide plays an important role in regulating cell proliferation and apoptosis. Recent studies indicate that generation of ceramide in the intestine from sphingomyelin hydrolysis may be implicated in colon cancer development. The enzymes that catalyze the further hydrolysis of ceramide in the intestine have, however, not been well investigated. Our data reveal the existence of a ceramidase (EC 3.

Integrating national Red Lists for prioritising conservation actions for European butterflies

Red Lists are very valuable tools in nature conservation at global, continental and (sub-) national scales. In an attempt to prioritise conservation actions for European butterflies, we compiled a database with species lists and Red Lists of all European countries, including the Macaronesian archipelagos (Azores, Madeira and Canary Islands). In total, we compiled national species lists for 42 coun

Geofysiker, drönare och geologer ger tillsammans en bättre bild av berget

Teknisk geologi vid Lunds tekniska högskola har i ett nyligen slutfört projekt, finansierat av Stiftelsen Bergteknisk Forskning (BeFo), undersökt om geofysiska mätningar med DCIP (kombinerade resistivitets- och IP-mätningar) kan ge bättre information om bergmassan i samband med planeringen av tunnlar och andra bergarbeten samt berguttag i bergtäkter. Resultaten bekräftar att DCIP i den undersökta

Bildliga betydelser i SAOB : Om beskrivningen av betydelseutvecklingsmekanismer analyserad ur ett kognitivt semantiskt perspektiv

Man talar ibland om bildligt språkbruk och bildliga betydelser, men vad är det för något egentligen, mer exakt? I Svenska Akademiens ordbok (SAOB) är många betydelser försedda med etiketten "bildl.". Faktum är att denna etikett förekommer mer än 40 000 gånger på ordbokens spalter. Trots det är de redaktionella anvisningarna vaga om hur den semantiska analysen av sådant språk ska genomföras. I den

MRI Perfusion Measurements using Magnetic Susceptibility Effects: : Calibration Approaches and Contrast Agent Quantification

Perfusion eller genomblödning är termer som används för att beskriva blodflödet i kroppens allra minsta kärl. Information om perfusion kan vara av stor betydelse för att ställa diagnos vid vissa sjukdomar, eftersom blodet transporterar det syre och den näring som behövs för att upprättahålla vävnadens funktion i kroppen. Ett viktigt exempel där information om perfusion kan vara till nytta för att Exchange of oxygen and nutrients between blood and tissue occurs at the capillary level of the blood system. The blood volume flow rate in the capillaries is often referred to as perfusion, and knowledge about perfusion provides important information about the function and viability of the tissue, for example, in patients with ischaemic stroke, cancer, and neurodegenerative diseases.Dynamic suscep

Embodying circularity through usable relocatable modular buildings

Purpose: Global megatrends such as urbanization and ageing of the population result in fast-paced demographic changes, which pose different types of challenges for different regions. While many rural municipalities bear the burden of under-used buildings, cities are in a hurry to develop new ones to meet new space demands. The purpose of this paper is to assess the potential of relocatable modular

Managing business networks for value creation in facilities and their external environments : A study on co-location

Purpose: The purpose of this paper is to increase understanding of the logic of business network formation among the co-located and external actors of a facility. Design/methodology/approach: The research adopts a theory-building approach through developing propositions inductively from the empirical case study on four purposefully sampled modern service station facilities. The focus is on analyzi