Abstract  The present study was conducted to follow up on apparent differences in growth, relative organ sizes, cellular stress and immune function in Atlantic salmon fed feed containing GM Bacillus thuringiensis maize compared with feed containing the non-modified parental maize line. Gene expression profiling on the distal intestinal segment and liver was performed by microarray, and selected genes were followed up by quantitative PCR (qPCR). In the liver, qPCR revealed some differentially regulated genes, including up-regulation of gelsolin precursor, down-regulation of ferritin heavy subunit and a tendency towards down-regulation of metallothionein (MT)-B. This, combined with the up-regulation of anti-apoptotic protein NR13 and similar tendencies for ferritin heavy chain and MT-A and -B in the distal intestine, suggests changes in cellular stress/antioxidant status. This corresponds well with and strengthens previous findings in these fish. To exclude possible confounding factors, the maize ingredients were analysed for mycotoxins and metabolites. The GM maize contained 90 μg/kg of deoxynivalenol (DON), while the non-GM maize was below the detection limit. Differences were also observed in the metabolite profiles of the two maize varieties, some of which seemed connected to the mycotoxin level. The effects on salmon observed in the present and previous studies correspond relatively well with the effects of DON as reported in the literature for other production animals, but knowledge regarding effects and harmful dose levels in fish is scarce. Thus, it is difficult to conclude whether the observed effects are caused by the DON level or by some other aspect of the GM maize ingredient.

Abstract  The low incidence of atherosclerosis and other degenerative diseases including stone disease in the Greenland Eskimo has been attributed to their high consumption of oily fish with its high concentration of eicosapentaenoic acid (EPA). Man cannot synthesis EPA from the precursor essential fatty acid, linolenic acid, and can only assimilate preformed EPA present in fish and fish oil, to bring about a change in the pathway of eicosanoid metabolism from the n-6 to the n-3 series. With a westernised diet the oxygenated products of renal prostaglandin synthesis are metabolites of the n-6 series and these are known to play an important role in several pathophysiological states including stone disease.

Our previous studies have shown a relationship between prostaglandin activity and urinary calcium excretion and it would seem that the initiating factor/s for stone formation trigger the mechanisms for prostaglandin synthesis resulting in the biochemical abnormalities associated with stone disease. The Eskimo may be protected from these events by possession of an eicosanoid metabolism that follows an n-3 pathway. To test this hypothesis experiments were performed using an animal model of nephrocalcinosis. The animals were divided into three groups; one group was given an intra-peritoneal injection of 10% calcium gluconate daily for 10 days to induce nephrocalcinosis; a second group was fed MaxEPA fish oil before and during the calcium gluconate injections and a third group only received an intra-peritoneal injection of N saline. A group of 12 recurrent, hypercalciuric/hyperoxaluric stone-formers were treated with fish oil for eight weeks to study the effects on solute excretion.

Nephrocalcinosis, which was readily produced in the control animals, was prevented in the experimental animals by pre-treatment with fish oil and urine calcium excretion was significantly reduced. The urinary calcium and oxalate excretion in the recurrent, hypercalciuric stone-formers was significantly reduced with fish oil treatment over an eight week period. There were no untoward side-effects. These studies indicate that the incorporation of EPA in the diet as a substitute metabolic pathway could be a unique way of correcting the biochemical abnormalities of idiopathic urolithiasis.

Abstract  Individual outer hair cells isolated from guinea pig cochleae were observed in vitro during the application of solutions that are known to cause hair cells to shorten. Solutions containing high potassium, which depolarizes cells, were applied in the form of potassium gluconate. The initial response was a shortening, followed by an elongation, after which the hair cells nearly resumed their original length. Solutions containing the presumed efferent neurotransmitter acetylcholine also caused an initial shortening, occasionally followed by an elongation, where a cell either returned to normal or exceeded its original length. Solutions containing cationized ferritin caused some cells to shorten and caused others to lengthen. The results indicate that the hair cell response to a chemical stimulus can be bidirectional. Moreover, the initial response of an individual cell may depend not only on the stimulus but also on the physiological state of the hair cell or the original location of the hair cell along the length of the sensory epithelium when it was in the cochlea.

Abstract  We evaluated the impact of three calcium salts on the calcium-parathyroid axis in healthy elderly volunteers. Fasting subjects were administered a standardized 1-g calcium load on three occasions, using calcium carbonate, lactate, and gluconate in random sequence with 8 oz milk or orange juice as carrier. Blood and urine were collected at baseline and for 6 h following the calcium load. Each salt rapidly increased the serum-calcium concentration and urinary-calcium excretion. Response duration was shorter with gluconate than with the other salts, but peak responses were similar for all preparations. Urinary-calcium excretion was slightly lower when orange juice replaced milk, but calcemic responses were not different. Changes in immunoreactive-parathyroid hormone and renal-phosphorus handling did not differ among calcium salts. Except for a shorter duration of effect with gluconate, all three calcium salts provided similar short-term suppression of the parathyroid axis.

Abstract  Calcium gluconate (22.4 g/day; 2 g/day as Ca) was administered orally for 8 weeks to eight hospitalized elderly patients with essential hypertension in order to confirm the hypotensive effect of oral calcium supplementation and to clarify its hypotensive mechanism by analyzing changes in hormonal factors. After 2 weeks of calcium supplementation, both systolic and diastolic pressures decreased significantly and remained decreased for the duration of the study. An elevation of plasma PGE2 correlated with blood pressure reduction was observed at 2 weeks. Plasma norepinephrine decreased significantly from 4 weeks. Plasma parathyroid hormone decreased significantly from 4 weeks, and 1,25-dihydroxyvitamin D (1,25-[OH]2D) decreased significantly at 8 weeks. The reduction of plasma 1,25-(OH)2D correlated with blood pressure decrease at 8 weeks. The present study indicates that the mechanism of its hypotensive effect is multifactorial and may be different during different phases of calcium supplementation. The suppression of plasma 1,25-(OH)2D following reduction of parathyroid hormone may be involved in the hypotensive effect in the chronic phase of calcium supplementation. Enhancement of PGE2 production in the early phase and suppression of sympathetic nervous activity in the chronic phase may also be factors in blood pressure reduction.

Abstract  Using anti-human calcitonin serum and a protein A - gold technique, calcitonin was localized at the ultrastructural level in control and calcium gluconate-stimulated thyroid C cells of the rat. In control rats calcitonin was detected within a majority of the secretory granules while in experimental animals it was demonstrated also within prosecretory granules present in Golgi apparatus.

Abstract  Adverse drug reactions impact on patient health, effectiveness of pharmacological therapy and increased health care costs. This investigation intended to detect the most critical drug-drug interactions in hospitalized elderly patients, weighting clinical risk. We conducted a cross-sectional study between January and April 2014; all patients 70 years or older, hospitalized for >24 hr and prescribed at least one medication were included in the study. Drug-drug interactions were estimated by combining Stockley's, Hansten and Tatro drug interactions. Drug-drug interactions were weighted using a risk-analysis method based on failure modes, effects and criticality analysis. We calculated a criticality index for each drug involved in the drug-drug interactions based on the severity of the interaction mechanism, the frequency the drug was involved in drug-drug interactions and the risk of drug-drug interactions in patients with impaired renal function. The average number of drugs consumed in the hospital was 6 ± 2.69, involving 160 active ingredients. The most frequent were as follows: Furosemide, followed by Enalapril. Of drug-drug interactions, 2% were classified as contraindicated, 14% advised against and 83% advised caution during the hospital stay. Thirty-four drug-drug interactions were assessed, of which 23 were pharmacodynamic drug-drug interactions and 12 were pharmacokinetic drug-drug interactions (1 was both). The clinical risk calculated for each drug-drug interaction included heparins + non-steroidal anti-inflammatory drugs (NSAIDs) or Digoxin + Calcium Gluconate, cases which are pharmacodynamic drug-drug interactions with agonist effect and clinical risk of bleeding, one of the most common clinical risks in the hospital. An index of clinical risk for drug-drug interactions can be calculated based on severity by the interaction mechanism, the frequency that the drug is involved in drug-drug interactions and the risk of drug-drug interactions in an elderly patient with impaired renal function.

Abstract  The aim of this study was to compare the side effects of the pentagastrin test and the calcium stimulation test in patients with increased basal calcitonin concentration, especially the gender-specific differences of side effects. A total of 256 patients (123 females and 133 males, mean age of 56 ± 27 years, range 21-83 years) had both pentagastrin and calcium stimulation tests. All patients filled in a questionnaire regarding the side effects within 30 min after completion of the stimulation tests. The differences of side effects between female and male patients as well as between the pentagastrin stimulation test and the calcium stimulation test were evaluated. Warmth feeling was the most frequent occurring side effect in all patients who had both pentagastrin and calcium stimulation tests, followed by nausea, altered gustatory sensation, and dizziness. The incidences of urgency to micturate (p < 0.05) and dizziness (p < 0.05) were significantly increased in the female patients as compared to male patients by calcium stimulation test. Significant higher incidences of urgency to micturate (p < 0.05) and warmth feeling (p < 0.05) were found by calcium stimulation test as compared with those by pentagastrin test in female patients. The incidences of nausea (p < 0.05) and abdominal cramping (p < 0.05) in male patients were significantly higher by pentagastrin stimulation test than by calcium stimulation test. There is a significant gender-specific difference in side effects induced by calcium stimulation test. Female patients have fewer side effects by pentagastrin test than by calcium stimulation test. Male patients may tolerate the calcium stimulation test better than the pentagastrin test.

Abstract  The effects of calcium gluconate on the utilization of magnesium and nephrocalcinosis in male Wistar rats made magnesium-deficient by adding excess dietary phosphorus (1.195 g of phosphorus/100 g of diet) and calcium (1.04 g of calcium/100 g of diet) were compared with the effects of calcium carbonate. The effects of dietary magnesium concentration on the magnesium status and nephrocalcinosis were also examined. Adding excess dietary phosphorus and calcium decreased the apparent magnesium absorption ratios and the concentrations of magnesium in the serum and femur and increased the deposition of calcium in the kidney, and the low magnesium condition (0.024 g of magnesium/100 g of diet) aggravated the deposition of calcium and the low magnesium status. The apparent magnesium absorption ratios and femur magnesium concentration in the rats fed a calcium gluconate diet (an equimolar mixture of calcium gluconate and calcium carbonate was used as a source of calcium) were significantly higher than in the rats fed a calcium carbonate diet (only calcium carbonate was used as a source of calcium), irrespective of dietary magnesium concentration. Dietary calcium gluconate lessened the accumulation of calcium in the kidney and increased the serum magnesium concentration compared with dietary calcium carbonate, when the rats were fed the normal magnesium diet (0.049 g of magnesium/100 g of diet) but not the low magnesium diet. We speculate that the increased utilization of magnesium by feeding the calcium gluconate diet to a limited extent prevented the low magnesium status and the severity of nephrocalcinosis caused by adding excess dietary phosphorus and calcium.

Abstract  Although it has been firmly established that D-glucose inhibits glucagon secretion from pancreatic A cells, the regulatory mechanism of glucagon secretion by D-glucose has not been elucidated. To study this regulatory mechanism by D-glucose, the effects of hexoses and their derivatives on glucagon secretion from the A cells of isolated perfused rat pancreas were investigated. When these cells were perfused with D-glucose, D-fructose, D-sorbitol, D-galactose, 2-deoxy-D-glucose, D-gluconic acid sodium salt and D-glucosamine HCl salt, glucagon secretion was significantly inhibited. None of the hexoses or their derivatives tested were found to stimulate glucagon secretion. The effects of these sugars on glucagon secretion were independent of their metabolism in the cells. From the findings that the sugars both metabolized and unmetabolized in the cells demonstrated comparable inhibition of glucagon secretion from the isolated perfused rat pancreas, it is speculated that the recognition system for these sugars may be probably present on the A cell membrane and responsible for mediating these inhibitory effects of glucagon secretion.

Abstract  Effects of several Cl(-) channel blockers on ionic currents in mouse embryos were studied using whole-cell patch-clamp and microelectrode methods. Microelectrode measurements showed that the resting membrane potential of early embryonic cells (1-cell stage) was -23 mV and that reduction of extracellular Cl(-) concentration depolarized the membrane, suggesting that Cl(-) conductance is a major contributor for establishing the resting membrane potential. Membrane currents recorded by whole-cell voltage clamp showed outward rectification and confirmed that a major component of these embryonic currents are carried by Cl(-) ions. A Cl(-) channel blocker, 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS), suppressed the outward rectifier current in a voltage- and concentration-dependent manner. Other Cl(-) channel blockers (5-nitro-2-[3-phenylpropyl-amino] benzoic acid and 2-[3-(trifluoromethyl)-anilino] nicotinic acid [niflumic acid]) similarly inhibited this current. Simultaneous application of niflumic acid with DIDS further suppressed the outward rectifier current. Under high osmotic condition, niflumic acid, but not DIDS, inhibited the Cl(-)current, suggesting the presence of two types of Cl(-) channels: a DIDS-sensitive (swelling-activated) channel, and a DIDS-insensitive (niflumic acid-sensitive) Cl(-) channel. Anion permeability of the DIDS-insensitive Cl(-) current differed from that of the compound Cl(-) current: Rank order of anion permeability of the DIDS-sensitive Cl(-) channels was I(-) = Br(-) > Cl(-) > gluconate(-), whereas that of the DIDS-insensitive Cl(-) channel was I(-) = Br(-) > Cl(-) > gluconate(-). These results indicate that early mouse embryos have a Cl(-) channel that is highly permeable to amino acids, which may regulate intracellular amino acid concentration.

Abstract  The regulation of PTH secretion by calcium is altered in patients with primary hyperparathyroidism. A similar disturbance may occur in secondary hyperparathyroidism, but direct in vivo comparisons of PTH secretion in normal subjects and those with secondary hyperparathyroidism have not been made. Thus, 13 patients with end-stage renal failure and secondary hyperparathyroidism and 20 healthy volunteers underwent dynamic tests of PTH secretion. Changes in ionized calcium were induced by 2-h iv infusions of calcium gluconate or sodium citrate on consecutive days, and the sigmoidal relationship between serum ionized calcium and PTH levels was examined. During sodium citrate infusions, serum ionized calcium levels decreased by 0.21 +/- 0.04 and 0.20 +/- 0.05 mmol/L, respectively (mean +/- SD), in normal volunteers and dialyzed patients (P = NS). Serum PTH levels rose from 27 +/- 7 to 107 +/- 33 pg/mL in controls and from 480 +/- 238 to 859 +/- 412 pg/mL in dialyzed subjects; thus, maximum PTH levels were 396% of preinfusion values in normal subjects, but only 79% greater than baseline values in dialyzed patients (P < 0.001). During the first 30 min of calcium infusions, the increase in serum ionized calcium did not differ between groups, but PTH levels fell more rapidly in normal volunteers; values were 24% of preinfusion levels in controls, but only 56% of the baseline in dialyzed patients (P < 0.01) after 30 min. Minimum PTH levels were attained after 50 min of calcium infusion in normal volunteers and after 70 min in dialyzed patients. The derived values for set-point were 1.21 +/- 0.04 and 1.24 +/- 0.06 mmol/L, respectively, in control and dialyzed subjects (P = NS). These results do not support the contention that the set-point for calcium-regulated PTH secretion is greater than normal in patients with secondary hyperparathyroidism due to end-stage renal disease.

Abstract  BIOSIS COPYRIGHT: BIOL ABS. A multinational interlaboratory study to investigate the bovine corneal opacity and permeability (BCOP) assay is presented. The aim of this work was to determine the capability and possible limitations of this method to predict ocular irritancy of a large set of chemicals. The assays were carried out in 12 European laboratories with different types of activity. In each of these laboratories 52 substances, with a wide range of structure, physical form and irritant properties, were tested and in vitro scores were compared with those obtained from concurrent rabbit eye (Draize) tests. The technique was easily learned by workers in the participating laboratories, as shown by the fact that there were consistent responses between treated corneas within an individual laboratory. Interlaboratory variability was also very good. It was found that a given laboratory had a 96% chance of classifying irritants or non-irritants similarly to the other laboratories. In addition, it was