Endocarditis at a large community hospital with on-site cardiac surgery.

Objective: Infective endocarditis (IE) is still a serious disease. The currently published EURO-ENDO registry showed a rate of surgery of 51.2% and a lower mortality in operated IE patients.

Transcatheter Mitral Valve Implantation (TMVI) Using Edwards SAPIEN 3 Prostheses in Patients at Very High or Prohibitive Surgical Risk: A Single-Center Experience.

Background: Mitral valve surgery in patients with failing bioprosthesis, annuloplasty rings, or in patients with advanced mitral annular calcification (MAC) is associated with high morbidity and mortality rates. Percutaneous antegrade transseptal transcatheter mitral valve implantation (TMVI) has recently successfully been performed in those patients at high or prohibitive surgical risk, but data on patients treated by TMVI are sparse. This study sought to evaluate short- and midterm outcomes of patients treated by TMVI at our site in clinical practice.

Farnesoid X receptor-dependent and -independent pathways mediate the transcriptional control of human fibroblast growth factor 19 by vitamin A.

Fibroblast growth factor 19 (FGF19) is a gut-derived hormone that controls bile acid (BA), carbohydrate and lipid metabolism. Whereas strong evidence supports a key role of BAs and farnesoid X receptor (FXR) for the control of FGF19 expression, information on other regulators is limited. In mice, FGF15 expression (ortholog of human FGF19) is induced by vitamin A (VitA) in an FXR-dependent manner.

Measurement of free palmitic acid in human bile.

Free palmitic acid has been measured in gallbladder bile from patients undergoing surgery for cholelithiasis. The mean concentrations were 0.079 and 0.

Ionised calcium in pathological human bile.

An automated ion-selective electrode system has been used to measure ionised calcium in bile from patients undergoing cholecystectomy for gallstones. Ionised calcium ranged from 0.63 to 1.

Urinary inhibitor of the formation of calcium oxalate.

Normal urine was examined for substances which inhibited the formation of calcium oxalate, using a separation scheme which involved ultrafiltration, alcohol precipitation, electrophoresis and paper chromatography. The major anionic inhibitors were found to be citric acid, isocitric acid and pyrophosphate. The inhibitory activity of urine and that of an artificial urine having the same concentration of urea, creatinine, sodium, potassiu, magnesium, calcium, ammonia, sulphate, chloride, inorganic phosphate, oxalate, citrate, isocitrate and pyrophosphate, and the same pH were identical.

Change in bile secretion in patients with calcium carbonate in their gallstones.

Common duct bile in patients with gallstones contains virtually no amylase activity. Therefore the raised levels of total CO2 concentrations found in common duct bile from patients with some calcium carbonate on the surface of their gallstones do not result from a reflux of pancreatic juice. A change in bile secretion is the likely explanation.

Urinary inhibitors of calcium phosphate formation: the inhibitory activity of normal and artificial urines.

Eelven urine samples from normal subjects inhibited the formation of calcium phosphate. In all cases the activity of the urine was identical with that of an artificial urine having the same concentration of urea, creatinine, sodium, potassium, magnesium, calcium, ammonia, sulphate, chloride, inorganic phosphate, citrate, isocitrate and pyrophosphate, and the same pH.

The effect of bile on the crystallisation of calcium carbonate, a constituent of gallstones.

When calcium and bicarbonate ions were mixed at room temperature (approximately 20 degrees C) to give concentrations of 4 mmol/1 and 21 mmol/1 respectively and the pH of the solution was kept at 8.3, vaterite, a form of calcium carbonate, was precipitated almost immediately as spheres of diameter 45 micron. The crystallisation of this material could be slowed down by adding to the crystallising medium small amounts of pyrophosphate or citrate which often inhibit crystal growth.

Isolation and identification of some urinary inhibitors of calcium phosphate formation.

Normal urine has been examined for substances which inhibit formation of calcium phosphate. A separation scheme involving ultrafiltration, precipitation, electrophoresis and paper chromatography was devised to isolate these substances. Contrary to what has been suggested in the literature for many years, the urines examined did not contain a potent unidentified inhibitor.

An assay method for the measurement of urinary inhibitors of calcium phosphate formation.

An assay method has been developed for studying quantitatively the formation of calcium phosphate. The method will detect both substances which affect the solubility of calcium phosphate and substances which affect the crystal growth of the material. It is sensitive as or more sensitive than other methods described in the literature for detecting such compounds.

The estimation of pyrophosphate in urine with uridine-5'-diphosphoglucose pyrophosphorylase.

The concentration of pyrophosphate in urine has been determined using the enzyme uridine-5'-diphosphoglucose pyrophosphorylase. The technique is relatively quick and easy to perform. Reproducibility of results was good, and results from recovery experiments were excellent.

The estimation of D-isocitric acid in urine using isocitrate dehydrogenase.

The amount of D-isocitric acid in urine has been estimated using the enzyme isocitrate dehydrogenase. The technique is rapid and easy to perform. Reproducibility of results was good and results from recovery experiments were excellent.

Calcium carbonate in human gallstones and total CO2 in bile.

Measurement of total CO2 concentrations in bile from patients undergoing cholecystectomy because of gallstones has shown that the presence of calcium carbonate in the stones can be associated with a raised total CO2 concentration in the common duct bile. In bile from functioning and poorly-functioning gallbladders, total CO2 was nearly always related to pH irrespective of stone composition.

Calcium in bile and calcium salts in gallstones.

In gallbladder and common duct bile from patients undergoing cholecystectomy, usually because of gallstones, calcium was found to exist in at least 2 forms. Ultrafiltration showed some calcium was bound to substances with a molecular weight greater than 10 000, and the chief binding agent is likely to be the mixed micelle. Bound calcium was significantly less in common duct bile than in bile from functioning gallbladders, but the amount of ultrafiltrable calcium was the same.

The crystalline salts of calcium bilirubinate in human gallstones.

1. The acid, neutral and "intermediate" salts of calcium bilirubinate have been synthesized. 2.

Inorganic phosphorus in human bile.

The inorganic phosphorus concentration has been measured in fresh bile from patients undergoing cholecystectomy, usually because of cholelithiasis. The amount in common duct bile for patients with cholesterol on the stone surface was significantly higher than that for patients with some calcium carbonate in this area. For all patients with functioning gallbladders, inorganic phosphorus in gallbladder bile was always higher than that in the corresponding common duct bile.

Diurnal variations in the pH of pathological gallbladder bile.

The pH of gallbladder and common duct bile from patients undergoing surgery for cholecystectomy has been measured. The bile was collected and kept anaerobically at 37 degrees C, and the pH measured at 37 degrees C, generally within 30-60 minutes of the bile being taken from the patient. Only data from patients having functioning or poorly-functioning gallbladders were included in the calculations.

An apparatus for the anaerobic ultrafiltration of bile and other biological fluids.

A simple apparatus is described for the anaerobic ultrafiltration of a few millilitres of bile or other biological fluids. The principle employed enables viscous liquids which would normally block the membrane to be ultrafiltered successfully.

Presence or absence of inhibitors of crystal growth in bile. 1. Effect of bile on the formation of calcium phosphate, a constituent of gallstones.

When calcium and phosphate ions were mixed so that their final concentration was 4 mmol/1 and the pH was kept at 7-0, an amorphous precipitate immediately formed and this changed into crystalline material with an apatite-like structure after a period of time. The formation of either or both types of precipitate could be slowed down or prevented by adding to the crystallising medium trace amounts of pyrophosphate or citrate which are known inhibitors of the formation of calcium phosphate, or large quantities of sodium chloride which increased the ionic strength of the solution and hence the solubility of calcium phosphate, Both common duct and gallbladder bile from patients with gallstones composed of cholesterol and/or calcium carbonate had a very pronounced inhibitory action on the formation of these precipitates. Only very small amounts of bile were necessary to produce these effects, which therefore were not due to an increase in ionic strength.

A simple method for studying the formation of calcium oxalate.

The nucleation and crystal growth of calcium oxalate were studied under different conditions using a nephelometer to measure the turbidities of suspensions produced when dilute solutions of calcium chloride dihydrate and sodium oxalate were mixed. The amount of material produced was less when calcium was in excess of oxalate than vice versa. For equimolar amounts of the precipitating reagents the rate of formation of calcium oxalate was rapid when calcium and oxalate concentrations were 1-25 mmol/l.

Some observations on gallstones and bile composition.

A series of 31 consecutive patients undergoing surgery for gallstone disease has been studied and the composition of the gallstones and bile from the gallbladder and common duct determined. As a result of the stone analysis by the X-ray powder diffraction method, the patients were classified according to whether their stones consisted of cholesterol, calcium salts or a mixture of the two. The mean composition of the common duct bile for the groups with cholesterol and mixed stones was just outside the micellar region of cholesterol solubility.

Constituents of urinary calculi containing struvite.

In a collection of 615 stones containing struvite and in which the sequential deposition of the constituents from the nucleus to the surface had been determined, other substances were found to follow a marked deposition of struvite in 139 cases. In 122, the compound was accompanied by struvite, in 16, struvite was replaced by it and in 1, both types of deposition had occurred in different layers. All urinary stone constituents could accompany struvite and many could replace this compound.

Gallbladder function, cholesterol stones, and bile composition.

Gallbladder bile obtained at operation from five patients with no symptoms of biliary disease was undersaturated with cholesterol in every case. However, gallbladder bile from patients with stones composed of 97-100% crystalline cholesterol was on average just saturated with cholesterol when the gallbladder was functioning and undersaturated when it was not. Regardless of gallbladder function, the patients with stones had on average significantly more cholesterol in their bile than in the control group, but the differences between the mean composition of bile from functioning and non-functioning gallbladders were not significant.

The value of radiology in predicting gallstone type when selecting patients for medical treatment.

Since medical treatment of gallstones is confined to cholesterol-rich stones, the ability of clinical radiographs to predict gallstone type was tested prospectively by comparing the preoperative radiological appearance of gallstones from 57 unselected patients with cholelithiasis coming to cholecystectomy with the subsequent analysis of the stones both by X-ray diffraction and by chemical techniques. Fifty-two per cent of the patients had 'non-functioning' gallbladders which failed to opacify after at least two contrast examinations and 25 out of 50 had radioopaque stones. Of the 25 patients with radiolucent stones, the stones in 20 ((80%) were predominantly cholesterol in type but radiology was misleading in five; three contained 40-55% calcium salts but were still radiolucent while two were amorphous and contained less than 10% cholesterol by weight on chemical analysis.