Lithogenicity of human bile is dependent not only on cholesterol saturation, but also on the presence of nucleating and antinucleating factors. Most of the research in this field is directed toward ...biliary proteins, particularly glycoproteins. In the present study we have shown that spermine, spermidine, cadaverine and putrescine have a nucleating effect in model bile as well as in native human bile. These findings are based on 183 mixing experiments using biles from 10 patients and model biles. The effect seems to be dose dependent at concentrations up to 10 mmol/l. It is not accompanied by a shift in cholesterol distribution between its vesicular and micellar carriers. It is at present uncertain whether these effects are pharmacologic or physiologic. These findings emphasize, however, the potential importance of non-protein compounds in the cholesterol nucleation process in bile.
Prostaglandin E2 in pyloric stenosis Goldman, G; Tiomny, E; Kahn, P J ...
Archives of surgery (Chicago. 1960),
06/1989, Letnik:
124, Številka:
6
Journal Article
Prostaglandins are presumed to have many cytoprotective properties that play a role in the pathogenesis of duodenal ulcer and its complications where decreased levels of prostaglandin E2 (PGE2) ...impair gastric motility, oppose ionic membrane influx, and enhance obstructive changes. These are just some of the mechanisms that may cause pyloric obstruction and may result from decreased PGE2 levels. To evaluate this hypothesis, 17 patients with duodenal ulcer complicated by pyloric stenosis were examined. Biopsy specimens were obtained from the duodenal bulb, ulcer margins, gastric antrum, fundus, and gastric secretions. Prostaglandin E2 levels were measured and compared with those taken from the same areas during a second endoscopy in a later quiescent or exacerbated phase. During the active phase of pyloric stenosis, decreased levels of PGE2 were found in the gastroduodenal tissues and secretions were compared with levels found during convalescence. These level differences were statistically significant. A correlation between the severity of the clinical and endoscopic findings and the PGE2 levels was found. A further decrease in PGE2 levels in the second endoscopy were indicative of the presence of scar tissue, representing an irreversible obstructive peptic disease.
Malignant cell growth is fueled by interactions between tumor cells and the stromal cells composing the tumor microenvironment. The human liver is a major site of tumors and metastases, but molecular ...identities and intercellular interactions of different cell types have not been resolved in these pathologies. Here, we apply single cell RNA‐sequencing and spatial analysis of malignant and adjacent non‐malignant liver tissues from five patients with cholangiocarcinoma or liver metastases. We find that stromal cells exhibit recurring, patient‐independent expression programs, and reconstruct a ligand–receptor map that highlights recurring tumor–stroma interactions. By combining transcriptomics of laser‐capture microdissected regions, we reconstruct a zonation atlas of hepatocytes in the non‐malignant sites and characterize the spatial distribution of each cell type across the tumor microenvironment. Our analysis provides a resource for understanding human liver malignancies and may expose potential points of interventions.
SYNOPSIS
Single cell transcriptomics and spatial methods are used to generate a cell atlas of the human liver tumor microenvironment, exposing recurring tumor‐stroma interactions and zonation patterns in the healthy and malignant tissue.
A single cell atlas of the malignant and adjacent non‐malignant human liver is presented.
Recurring stromal cell gene expression signatures are found in liver metastases and cholangiocarcinomas.
Tumor and stromal cells communicate through a conserved ligand‐receptor interaction network.
Spatial transcriptomics reveal zonated expression patterns in the malignant and non‐malignant liver.
Single cell transcriptomics and spatial methods are used to generate a cell atlas of the human liver tumor microenvironment, exposing recurring tumor‐stroma interactions and zonation patterns in the healthy and malignant tissue.
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