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To cite this article: M€ uller MCA, Straat M, Meijers JCM, Klinkspoor JH, de Jonge E, Arbous MS, Schultz MJ, Vroom MB, Juffermans NP. Fresh frozen plasma transfusion fails to influence the hemostatic balance in critically ill patients with a coagulopathy. J Thromb Haemost 2015; 13: 989-97.Summary. Background: Coagulopathy has a high prevalence in critically ill patients. An increased International Normalized Ratio (INR) is a common trigger to transfuse fresh frozen plasma (FFP), even in the absence of bleeding. Therefore, FFP is frequently administered to these patients. However, the efficacy of FFP in correcting hemostatic disorders in non-bleeding recipients has been questioned. Objectives: To assess whether INR prolongation parallels changes in the results of other tests investigating hemostasis, and to evaluate the coagulant effects of a fixed dose of FFP in non-bleeding critically ill patients with a coagulopathy. Methods: Markers of coagulation, individual factor levels and levels of natural anticoagulants were measured. Also, thrombin generation and thromboelastometry (ROTEM) assays were performed before and after FFP transfusion (12 mL kg À1 ) to 38 non-bleeding critically ill patients with an increased INR (1.5-3.0). Results: At baseline, levels of factor II, FV, FVII, protein C, protein S and antithrombin were reduced, and thrombin generation was impaired. ROTEM variables were within reference ranges, except for a prolonged INTEM clot formation time. FFP transfusion increased the levels of coagulation factors (

A mechanistic model of mucous granule exocytosis by columnar epithelial cells must take into account the unique physical-chemical properties of mucin glycoproteins and the resultant mucus gel. In particular, any model must explain the intracellular packaging and the kinetics of release of these large, heavily charged species. We studied mucous granule exocytosis in gallbladder epithelium, a model system for mucus secretion by columnar epithelial cells. Mucous granules released mucus by merocrine exocytosis in mouse gallbladder epithelium when examined by transmission electron microscopy. Spherules of secreted mucus larger than intracellular granules were noted on scanning electron microscopy. Electron probe microanalysis demonstrated increased calcium concentrations within mucous granules. Immunofluorescence microscopic studies revealed intracellular colocalization of mucins and the cystic fibrosis transmembrane conductance regulator (CFTR). Confocal laser immunofluorescence microscopy confirmed colocalization. These observations suggest that calcium in mucous secretory granules provides cationic shielding to keep mucus tightly packed. The data also suggests CFTR chloride channels are present in granule membranes. These observations support a model in which influx of chloride ions into the granule disrupts cationic shielding, leading to rapid swelling, exocytosis and hydration of mucus. Such a model explains the physical-chemical mechanisms involved in mucous granule exocytosis.

Intestinal epithelial cells secrete a protective luminal mucus barrier inhibiting viral gene transfer. Quiescent, polarized monolayers of primary epithelial cells from dog gallbladder and human colon are efficiently transduced through the apical mucus side by lentivirus vectors, suggesting their application to intestinal gene therapy.

Biliary infection is associated with mucin hypersecretion by the biliary epithelium. Mucins have been identified as potent pronucleators of cholesterol in bile. The aim of the present study was to determine whether lipopolysaccharides (LPS) from different bacteria are capable of stimulating mucin secretion by cultured dog gallbladder epithelial (DGBE) cells, and to investigate the mechanism by which LPS stimulate mucin secretion. Mucin secretion by confluent monolayers of DGBE cells was quantified by measuring the secretion of [3H]-N-acetyl-D-glucosamine-labeled glycoproteins. Cell viability was evaluated by measuring the leakage of the enzyme, lactate dehydrogenase (LDH), into the culture medium. LPS, derived from Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa (200 g/mL), all caused an increase in mucin secretion by the DGBE cells, without causing concomitant cell lysis. LPS from E. coli was found to be the most potent stimulator of mucin secretion, and increased mucin secretion by the DGBE cells to 252% ؎ 14% of control. LPS from E. coli had no effect on intracellular cyclic adenosine monophosphate (cAMP) levels in the DGBE cells. Addition of the nitric oxide (NO)-releasing compound, NOR-4 (0.125-1 mmol/L), to the cells did not result in increased mucin secretion, and the NO synthase inhibitor, N -nitro-L-arginine methyl ester (L-NAME) (4 or 10 mmol/L), did not inhibit the LPSstimulated mucin secretion. Exogenous tumor necrosis factor ␣ (TNF-␣) (1-10 ng/mL) did cause a minor increase in mucin secretion by the DGBE cells, but the effect of LPS from E. coli on mucin secretion could not be inhibited by preincubation with a TNF-␣ antibody (10 g/mL). We conclude that LPS stimulates mucin secretion by the gallbladder epithelium. Whether this stimulation is mediated by TNF-␣ remains to be determined. (HEPATOLOGY 1999;29:1352-1357.)Gallbladder mucin, the primary glycoprotein secreted by the gallbladder, is a densely glycosylated macromolecule with a molecular mass of approximately 2 ϫ 10 6 d. Mucin is regarded as an important contributing factor to gallstone formation. [1][2][3] Mucin has been shown to be present in the nucleus of several types of gallstones, and a macromolecular complex of mucin and bilirubin has been identified as a major structural component of the gallstone matrix. 4,5 Purified human gallbladder mucin is capable of nucleating cholesterol crystals from human bile. 6 Gallbladder mucus hypersecretion and increased mucin concentration are common findings in nearly all animal models of cholesterol gallstone disease. Mucin hypersecretion precedes crystal or stone formation. 7,8 These findings suggest that increased mucin secretion plays a role in the initial stages of gallstone formation.We have reported the succesful long-term culturing and passaging of normal, well-differentiated gallbladder epithelial cells from the dog. 9 These cells form electrically leakproof monolayers and synthesize protein and mucous glycoprotein. They have been extensively studied with regard to water and ...