Glycerol interference in serum lipase assay falsely indicates pancreas injury

The measurement of serum lipase activity has been shown to be a very sensitive and specific marker for the diagnosis of pancreatic injury. Two case reports are presented showing that glycerol ingested coincidentally in the formulation of several medications taken therapeutically and given in the emergency room causes a falsely elevated serum lipase activity when measured on the Kodak Ektachem 700 clinical analyzer (Eastman Kodak Co., Rochester, NY). The transient but falsely elevated serum lipase activity could potentially affect the differential diagnosis of patients by the admitting physician.

Background calcium permeable channels in glomerulosa cells from adrenal gland

The cell-attached recording mode of the patch-clamp technique was used to study Ca2+ permeable background currents of glomerulosa cells from rat and bovine adrenal gland. With a pipette filled with 110 mM BaCl2 or 90 mM CaCl2, three different types of unitary currents were detected. The B1 channel demonstrates a nonlinear I-V curve. The conductances are 4 and 7 pS at -40 and -70 mV, respectively. The curve of the opening probability vs. membrane potential is bell shaped with its maximum at -70 mV. The B2 channel has a conductance of 6 pS, while the B3 channel shows a nonlinear I-V relationship with conductances close to 17 and 10 pS at HPs of -60 and -20 mV. The three types of currents are insensitive to dihydropyridines. We suggest that these background currents could be responsible for the basal calcium influx and aldosterone secretion previously observed in nonstimulated glomerulosa cells.

Fluorescent peptide hormones: development of high affinity vasopressin analogues

Highly potent and specific peptide hormone analogues with fluorescent reporter groups are current research goals. Until now, however, only moderately potent analogues have been described. We report here several types of vasopressin (VP) analogues with different fluorophores attached to the peptide. In a first series, fluorophores were attached to the free epsilon amino function of [des-amino1-lysine8]VP (dLVP), producing agonistic analogues. In a second series, reporter groups were added to the N-terminal of open-chain antagonist structures. The biological activities of these analogues were assessed by two different sets of experiments: 1) The measurement of their binding affinities towards the V1a-vasopressin receptor subtype from WRK1 cells or rat liver membrane preparations; 2) Their ability to stimulate the phospholipase C activity in WRK1 cells. As expected, a simple acylation of fluorophores to dLVP resulted in a considerable loss of affinity. If however, the Lys8 side chain was extended through double Schiff-base formation with glutaraldehyde-ethylenediamine followed by reduction to an aminoalkyl aminoalkylamine, single fluorophores could be added without loss of affinity compared to VP. The open-chain analogues, on the other hand, while displaying weak affinity, nevertheless exhibited pure antagonistic behavior.

Technetium-99m sestamibi tomography in patients with spontaneous chest pain: correlations with clinical, electrocardiographic and angiographic findings

The sensitivity and specificity of technetium-99m hexakis-2-methoxy-2-isobutyl-isonitrile (sestamibi) single-photon emission computed tomographic (SPECT) imaging for the diagnosis of coronary artery disease were studied in 45 patients admitted to the hospital for clinical suspicion of unstable angina. Only patients without prior myocardial infarction were included and all patients had technetium-99m sestamibi injection and a 12-lead electrocardiogram (ECG) during and less than or equal to 4 h after an episode of chest pain. Coronary angiography performed in all patients during hospitalization showed significant coronary artery disease (greater than or equal to 50% luminal diameter reduction) in 26 of the 45 patients. The SPECT studies obtained after injection of technetium-99m sestamibi during an episode of spontaneous chest pain showed a sensitivity of 96% for the detection of coronary artery disease; the 12-lead ECG obtained at the time of the injection had a sensitivity of 35%. With the patient in the pain-free state, respective sensitivity values were 65% and 38%. Specificity for the radionuclide study was 79% during pain and 84% in the pain-free state; for the ECG, it was 74% both during and between episodes of pain. The site of the perfusion defect corresponded to the most severe coronary artery lesion in 88% of patients. The severity of the perfusion defect correlated with the extent of coronary artery disease: the defect score was 5.3 +/- 3.3 with one-vessel disease, 4.9 +/- 2.8 with two-vessel disease and 10.5 +/- 5.0 with three-vessel disease (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Lipase and pancreatic amylase activities in tissues and in patients with hyperamylasemia

Lipase, pancreatic amylase, and total amylase activities were measured in nondiseased and diseased human pancreatic tissues and in six different locations of the human digestive system. In addition, it was determined whether serum lipase and pancreatic amylase tests could replace the total amylase test to improved diagnostic efficiency in the evaluation of acute pancreatitis in hyperamylasemia patients. Nondiseased pancreatic tissue contained 4.5 times more lipase activity than total amylase activity. Diseased pancreatic tissue contained less activity for both lipase and total amylase compared to normal tissue. The total amylase activity of the pancreas was comprised solely of pancreatic amylase. Tissue obtained from six different anatomic locations in the digestive system contained 35 to 45 times less lipase and total amylase activity compared to the pancreas. Total amylase activity of the digestive system tissues were comprised of 25% pancreatic and 75% salivary isoamylases. Lipase, pancreatic amylase, and total amylase levels also were determined in serial serum samples from 17 consecutive hyperamylasemia patients admitted with possible acute pancreatitis. The serum lipase level remained higher than normal longer than either the total amylase and pancreatic amylase levels. In patients with hyperamylasemia of pancreatic origin, a poor correlation was observed at admission between serum pancreatic amylase and serum lipase. Not all patients with elevated lipase had an elevated pancreatic amylase level and vice versa. However, in every patient pancreatic disease would have been detected by the elevation of either lipase or pancreatic amylase levels. Diagnostic efficiency for pancreatic disease using serum pancreatic amylase, lipase, and total amylase tests was 94.1%, 76.5%, and 64.7%, respectively. These data suggest that lipase and pancreatic amylase tests are specific for the pancreas and might be considered replacements for total amylase as the stat or routine laboratory test for the diagnosis of pancreatic tissue injury.

Spectrofluorimetric and image recordings of spontaneous and lectin-induced cytosolic calcium oscillations in Jurkat T cells

Intracellular variations in Ca2+ concentrations have been measured in single Jurkat T lymphocyte variants (77 6.8 and E6.1) using Fura-2 as a probe. Under basal conditions, the cytosolic Ca2+ level is stable but some cells show spontaneous Ca2+ oscillations (frequency, 0.30 +/- 0.06 Hz). These oscillations are sensitive to the external concentration of Ca2+ since they can no longer be observed when the bathing solution is replaced (superfusion) with a Ca(2+)-free medium or when a Ca2+ chelator (EGTA) is added. Various changes in the cytosolic concentration of Ca2+ ([Ca2+]i) can be observed when the cells are exposed to the mitogenic lectin phytohemagglutinin (PHA, 80 nM). For instance, in the case of non-oscillating cells, the lectin induces either a rapid increase in [Ca2+]i that is followed by a sustained response (plateau) or it triggers Ca2+ spikes. In the case of experiments done in Ca(2+)-free medium, only the initial spike was observed. In the case of spontaneously oscillating cells, PHA induces a rapid increase in [Ca2+]i that is followed by a plateau where oscillations are absent. In every case, the PHA-dependent Ca2+ response is abrogated in a Ca(2+)-free medium. Computer simulations based on the model of Goldbeter et al. [27] show that the various Ca2+ responses of Jurkat cells are related to the cytosolic level of free Ca2+. Video imaging analyses show that the cellular Ca2+ responses are not homogeneous whether the observations are made in spontaneously oscillating Jurkat cells or when they are exposed to PHA.

Roentgen findings in occipital pole tumors

The arteriographic findings of occipital pole tumors consist of the following:1. Anterior displacement and elevation of the middle cerebral group.2. "Accordioning" of the anterior choroidal artery.3. Anterior displacement of the lateral branch of the posterior choroidal artery.4. Local stretching of vessels about the tumor.5. "Onion skinning" of the pial vessels.6. Anterior displacement of the vein of the occipital horn.7. Greater displacement of the internal cerebral vein than of the anterior cerebral artery. Air studies require precise radiographic technique lest the subtle displacements of the occipital horn and trigone area be missed.