Abstract  HEEP COPYRIGHT: BIOL ABS. Toxicity of 80 chemicals which have food additive use were investigated by administration to developing chicken embryos. Test conditions (4) were used: injection via air cell and via yolk; and at 2 times, preincubation (0 h) and 96 h. For each condition, at least 100 embryos/dose level were treated at a minimum of 5 dose levels. Appropriate groups of vehicle controls and untreated controls were included in all experiments. LD50 values were determined for each test condition. All embryos and hatched chicks were examined grossly for abnormalities in development, both functional and structural. All abnormalities were tabulated and compared with values for vehicle controls to determine teratogenicity. Organic and inorganic chemicals were tested, including gums and flavoring agents. Levels tested ranged from 0.50-75 mg/egg; the maximum volume injected with 100 mul. In some cases, test levels were low because of inability to find a nontoxic solvent for test chemical. No toxic compounds were found among those tested. A range of LD50 values was found. Investigation of teratogenicity of these chemicals revealed that 10 of 80 produced significant numbers of abnormal birds under 1 or more test conditions. Chicken embryo test can demonstrate the teratogenic potential of compounds. It is selective and does not respond nonspecifically to any agent introduced during development. The test may be useful for screening large numbers of compounds to identify those that should be subjected to more rigorous evaluation.

Abstract  Firstly, to determine a satisfactory animal model for induction of intrarenal calcification, a study of four previously described animal models of intrarenal calcification was carried out which showed that intraperitoneal injection of 10% calcium gluconate into female Sprague-Dawley rats was most effective. We then investigated the hypothesis that dietary supplementation with essential fatty acids could reduce the intrarenal calcification developing as a result of intraperitoneal calcium injection. Using a combination of fish oil and evening primrose oil, we demonstrated a significant difference in renal parenchymal calcification, which was 940 +/- 240 mu g Ca/g dry weight renal parenchyma in unsupplemented animals and 320-370 +/- 55-65 mu g Ca/g dry weight renal. parenchyma in supplemented animals (means +/- SEM, P < 0.005). It was also demonstrated that there was synergism between eicosapentaenoic acid (EPA) and gamma-linolenic acid (GLA): dietary supplementation with a combined oil preparation containing 27 mg/ml EPA and 67 mg/ml GLA mixed as 2% with food was as effective as oils containing either 400 mg/ml EPA or 80 mg/ml GLA mixed as 4% of food.

Abstract  It is known that calcium induces the formation of potent vasodilators in endothelial cells and vasocontriction in smooth muscle cells, whereas in the renal parenchyma, it modulates sodium excretion through vascular and tubular mechanisms. Consequently, an increased concentration of calcium in renal circulation may induce a sequence of contrasting hemodynamics and excretory effects depending on the threshold of a particular mechanism that is first being stimulated. In order to identify this sequence of responses and their respective thresholds, we infused into the renal artery of anesthetized dogs progressively increasing doses of calcium gluconate that ranged from 1 to 400-mu-g/kg/min.

The administration of 1, 10, and 100-mu-g/kg/min of calcium gluconate was followed by a significant increase in urinary excretion of PGE2 and 6-keto-PGF1-alpha and by a marked diuresis and natriuresis without altering renal blood flow (RBF) or glomerular filtration rate (GFR). Renin release was increased by 80% only during the infusion of the 10-mu-g/kg/min dose. The intrarenal infusion of a 400-mu-g/kg/min dose of calcium produced marked decreases in RBF and GFR, while urine sodium excretion (U(Na)V), U(PGE2)V, and U6-keto-PGF1-alpha-V continued and were markedly elevated. During all these maneuvers, mean arterial pressure remained unchanged. After the administration of indomethacin, the intrarenal infusion of 10 and 100-mu-g/kg/min of calcium produced marked reductions in urine prostaglandins and caused a decrease in RBF and GFR comparable to those obtained with the 400-mu-g/kg/min dose, abolished completely the increments in urine volume and urine sodium, and prevented the increase in renin produced by the 10-mu-g/kg/min dose. These studies show that all the intrarenal effects of low doses of calcium are dependent on the production of prostaglandins. The use of systemic infusion of calcium gluconate as a specific probe to test the renal ability to produce prostaglandins is further emphasized by the finding that in humans the threshold of renal responses to calcium is much greater than that of the systemic circulation.

Abstract  Gluconic acid is a multifunctional organic acid used as a bulk chemical in the food, feed, pharmaceutical, textile, metallurgy, detergent, paper, and construction industries. It is derived from glucose through a simple oxidation reaction catalyzed by glucose oxidase (EC 1.1.3.4.). Oxidation of the aldehyde group on C-1 of β-d-glucose to a carboxyl group results in the production of glucono-δ-lactone (C6H10O6) and hydrogen peroxide using molecular oxygen as the electron acceptor. Glucono-δ-lactone is further hydrolyzed to gluconic acid either spontaneously or by lactone-hydrolyzing enzyme. There are various approaches such as chemical, biochemical, and electrochemical available for its production, but microbial fermentation by Aspergillus niger using glucose oxidase is the most widely studied method. Microbial production of gluconic acid by bacteria, Gluconobacter, has also been demonstrated well. The enzyme involved in this process is glucose dehydrogenase. This chapter gives a review of microbial gluconic acid production; its recovery, properties, and applications; and the enzyme glucose oxidase.

Abstract  Agro-industrial by-products and wastes pose serious, widespread problems with considerable economic and environmental consequences in developed countries. However, many of the by-products contain large amounts of sugars that make them potentially excellent raw materials for the biotechnological production of added value products; in particular, by-products from perishables such as fruits can be highly useful for this aim. The growing significance and demand for gluconic acid have promoted an interest in integrating both issues as a strategy for the revalorization of these resources.

The pertinence of this strategy can be better understood by examining the properties of gluconic acid and its derivatives and their uses and production methods, especially biotechnological methods, to update the existing reviews on the topic.

Future advances in this direction may be promoted by the development of genetically modified organisms for the generation of new technological processes and the optimization of existing ones. Particular attention is paid to acetic acid bacteria. (C) 2016 Elsevier Ltd. All rights reserved.

Abstract  Daphnia are highly sensitive to sodium metabolism disruption caused by aquatic acidification and ionoregulatory toxicants, due to their finely balanced ion homeostasis. Nine different water chemistries of varying pH (4, 6 and 8) and calcium concentration (0, 0.5 and 1 mmol l(-1)) were used to delineate the mechanism of sodium influx in Daphnia magna. Lowering water pH severely inhibited sodium influx when calcium concentration was high, but transport kinetic analysis revealed a stimulated sodium influx capacity (J(max)) when calcium was absent. At low pH increasing water calcium levels decreased J(max) and raised K(m) (decreased sodium influx affinity), while at high pH the opposite pattern was observed (elevated J(max) and reduced K(m)). These effects on sodium influx were mirrored by changes in whole body sodium levels. Further examination of the effect of calcium on sodium influx showed a severe inhibition of sodium uptake by 100 micromol l(-1) calcium gluconate at both low (50 micromol l(-1)) and high (1000 micromol l(-1)) sodium concentrations. At high sodium concentrations, stimulated sodium influx was noted with elevated calcium levels. These results, in addition to data showing amiloride inhibition of sodium influx (K(i)=180 micromol l(-1)), suggest a mechanism of sodium influx in Daphnia magna that involves the electrogenic 2Na(+)/1H(+) exchanger.

Abstract  Objective: To explore the effects of calcium gluconate and thrombin on the formation of platelet-rich gel (PRG) and the release of bioactive substances in human platelet-rich plasma (PRP) and the clinical significance. Methods: Six healthy blood donors who met the inclusion criteria were recruited in our unit from May to August in 2016. Platelet samples of each donor were collected for preparation of PRP. (1) PRP in the volume of 10 mL was collected from each donor and divided into thrombin activation group (TA, added with 0.5 mL thrombin solution in dose of 100 U/mL) and calcium gluconate activation group (CGA, added with 0.5 mL calcium gluconate solution in dose of 100 g/L) according to the random number table, with 5 mL PRP in each group. Then the PRP of the two groups was activated in water bath at 37 ℃ for 1 h. The formation time of PRG was recorded, and the formation situation of PRG was observed within 1 hour of activation. After being activated for 1 h, one part of PRG was collected to observe the distribution of fibrous protein with HE staining, and another part of PRG was collected to observe platelet ultrastructure under transmission electron microscope (TEM). After being activated for 1 h, the supernatant was collected to determine the content of transforming growth factor β(1, )platelet-derived growth factor BB (PDGF-BB), vascular endothelial growth factor, basic fibroblast growth factor (bFGF), epidermal growth factor, and insulin-like growth factorⅠby enzyme-linked immunosorbent assay. (2) Another 10 mL PRP from each donor was collected and grouped as above, and the platelet suspension was obtained after two times of centrifugation and resuspension with phosphate buffered saline, respectively. And then they were treated with corresponding activator for 1 h as that in experiment (1). Nanoparticle tracking analyzer was used to detect the concentrations of microvesicles with different diameters and total microvesicles derived from platelet. Data were processed with t test. Results: (1) The formation time of PRG in group TA was (228±40) s, and the PRG volume reached the maximum at this moment. The PRG volume shrunk to the minimum after 30 minutes of activation. The formation time of PRG in group CGA was (690±71) s, and the PRG volume reached the maximum at this moment. After 55 minutes of activation, the PRG volume shrunk to the minimum. The formation time of PRG in group TA was obviously shorter than that in group CGA (t=15.17, P<0.01). (2) HE staining showed that after 1 hour of activation, the red-stained area of fibrous protein in PRG of group TA was large and densely distributed, while that of group CGA was small and loosely distributed. TEM revealed that after 1 hour of activation, the platelets in PRG of group TA were fragmented, while lysing platelet structure, lysing α granule structure, intact α granule structure, and intact dense body structure were observed in PRG of group CGA. (3) The content of PDGF-BB released by PRP in group TA was (7.4±0.8) ng/mL, which was obviously higher than that in group CGA [(4.9±0.5) ng/mL, t=5.41, P<0.01]. The content of bFGF released by PRP in group CGA was (960±151) pg/mL, which was significantly higher than that in group TA [(384±56) pg/mL, t=8.75, P<0.01]. The content of the other 4 growth factors released by PRP in the two groups was close (with t values from 0.11 to 1.97, P values above 0.05). (4) The concentrations of total microvesicles, microvesicles with diameter more than 100 nm, and exosomes with diameter less than or equal to 100 nm derived from platelet in group CGA were (165.8±15.1)×10(8)/mL, (142.4±12.3)×10(8)/mL, and (23.4±2.9)×10(8)/mL respectively, which were significantly higher than those in group TA [(24.7±4.6)×10(8)/mL, (22.6±4.0)×10(8)/mL, and (2.1±0.7)×10(8)/mL, with t values from 17.36 to 22.66, P values below 0.01]. Conclusions: Calcium gluconate can slowly activate PRP, resulting in slowly shrunk PRG with high content of bFGF and high concentration of microvesicles, which is suitable for repairing articular cavity and sinus tract wound. Thrombin can rapidly activate PRP, resulting in quickly shrunk PRG with high content of PDGF-BB and a certain concentration of microvesicles, which is suitable for repairing acute trauma.

Abstract  INTRODUCTION: Calcium gluconate extravasation is a process, which, while not common, occurs more frequently in neonatal intensive care units. The aim of this study is to present a number of cases of calcium gluconate extravasation, which have occurred in our hospital, and to carry out a review of those clinical cases published in the literature to obtain relevant epidemiological data.

METHODS: Data were gathered on the medical histories of 5 patients who presented lesions secondary to calcium gluconate extravasation in our center. A review of the literature was also performed to include clinical cases of calcium gluconate extravasation already published.

RESULTS: Data were collected on 60 cases published in 37 articles. Most patients (55%) were neonates. The average age of these neonates was 8 days. The commonest location of injuries was the back of the hand and wrist (42%). The 2 most frequent symptoms were the appearance of erythema (65%) and swelling/edema (48%) followed by the appearance of skin necrosis (47%), indurated skin (33%), and yellow-white plaques or papules (33%). Most cases are cured within a period of 3 to 6 months. Fifty percent of patients required surgery, and in 13% of cases, skin grafts were performed. The most frequent histological finding was the presence of calcium deposits. Other histological findings described were the presence of necrosis, lymphohistiocytic infíltrate, and granulomas. Most histological findings were located in the dermis. Most x-rays showing calcium deposits had been performed at 3 to 4 weeks.

CONCLUSIONS: Calcium gluconate extravasation is a process, which, although infrequent, is associated with serious skin and soft-tissue lesions, mainly affecting infants. Further studies are needed to determine possible specific procedures to be carried out in these cases.

Abstract  Metaldehyde, a cyclic polymer of acetaldehyde, is the active ingredient in many of the slug and snail baits used in the coastal and low lying areas of the United States (US) and Europe. Over 4.5 million kg of metaldehyde were used in households across the US from 1976 to 1977. Metaldehyde has also been used as a portable solid fuel. It is more efficient than silver iodide as a cloud-seeding chemical and has been listed as an anesthetic.

Abstract  Mutagenic test results are reported in microbial and mammalian cell systems.

Abstract  Over a 2‐year period in Dundee City hospitals, 16.5% of babies in the specical care baby unit (SCBU) received drugs, being given a mean number of 2.2 drugs each, compared with 2.3% of maternity ward babies who received a mean of 1.2 drugs each. In the SCBU, 26.5% of ‘low birth weight’ (< 2,500 g) babies and 32.1% of pre‐term (< 37 weeks) babies received drugs, as compared with 11.9% of ‘normal weight’ ( 2,500 g) babies, and 11.0% of term ( 37 weeks) babies. There was no apparent relationship between the mean number of drugs received by babies and their birth weight or gestational age. Antimicrobials were the most frequently prescribed drugs, and of the others, calcium gluconate was used most commonly.

Abstract  Estimate of acceptable daily intake for man. ADI "not specified". The fact that high doses of GDL exert a laxative effect in man should be taken into account when considering its level of use.