Effects Of Different Calcium Concentrations Research Articles

Evaluation of the effect of calcium concentration in the wool of sires on se- men quality characteristics

   Chemical elements, as structural components of the body, influence physiological processes and functions of the organism, growth, productive and reproductive traits, resistance and others.   In this regard, the present study aimed to evaluate the effect of different calcium concentrations in the wool of Holstein sires on the semen quality characteristics.   The studies were conducted in conditions of Leningrad and Vologda regions on Holstein sires, 3–5 years old (n = 40). Calcium concentration in wool was determined by atomic emission and mass spectrometry (AES–ICP and MS–ICP). According to the results of this analysis and comparison with previously developed reference intervals, we formed four groups of sires: I – level of Ca concentration less than 25th percentile, II and IV – within 25–75th percentile (physiological norm: 1597–2926 mg/kg) and III – more than 75th percentile. As a result of this distribution, the Ca concentration in the wool of animals of Group II was higher by 75.9 % compared to Group I; in turn, individuals of Group IV exceeded Group III – by 27.9 %. According to the results of semen quality characteristics evaluation, it was found that in the group of sires with Ca level within the previously developed reference intervals, the concentration of spermatozoa was higher by 15.3 % and their activity – by 0.17 points in fresh semen in comparison with the group with its reduced level (below the 25th percentile). High Ca content (above the 75th percentile) in wool contributed to a 9.0 % decrease in the concentration of spermatozoa compared to its average values. Thus, the calcium concentration, assessed by its level in the fur, affects the concentration and activity of sperm. It is necessary to evaluate it to improve the quality characteristics of sperm systematically.

Effects of different calcium concentrations on the outdoor growth of Nostoc sphaeroids Kütz

The technology of indoor cultivation of Nostoc sphaeroids Kütz is relatively mature, but for industrial cultivation, indoor cultivation has the disadvantages of high energy consumption and high cost. In order to find the appropriate amount of calcium concentration required for outdoor cultivation, and to pave the way for mass production of Nostoc sphaeroids Kütz, in this study, the Nostoc sphaeroids Kütz wwas cultivated. The pH, chlorophyll content, polysaccharide content, protein content and phytolithoprotein content of Nostoc sphaeroids Kütz were measured in different concentrations of calcium nutrient solution. The result showed that, with the increase of calcium concentration in outdoor cultivation, the growth of Nostoc sphaeroids Kütz was firstly inhibited and then promoted.

The calcium concentration of peritoneal dialysis solution modifies levels of key mediators of peritoneal fibrosis.

BackgroundTo explore the effects of different calcium concentrations of peritoneal dialysis solution (PDS) on continuous ambulatory peritoneal dialysis (CAPD) and expression of vimentin (VIM), fibroblast‐specific protein (FSP1), and E‐cadherin.Materials and MethodsThis was a pilot study (#ChiCTR1900021387) conducted from January 2017 to December 2019 at the Hospital. The patients were randomized to undergo CAPD using PDS with a calcium concentration of 1.25 mmol/L (low concentration group) or 1.75 mmol/L (high concentration group). Changes in biochemistry before dialysis and at 6 and 12 months were analyzed.ResultsThere were 50 and 52 participants in the low and high calcium groups. The blood biochemical indexes were all different between the two groups (all P time < .05, P group < .05, P interaction < .05), but they remained within their normal ranges. VIM and FSP1 increased over 12 months (P time < .05); VIM and FSP1 levels in the high concentration group were higher than in the low concentration group (P group < .05, P interaction < .05), while E‐cadherin showed the inverse association (P time < .001, P group < .001, P interaction < .001). There was no difference in complications (P = .973).ConclusionThe calcium concentration in PDS might be an important factor affecting the progression of peritoneal fibrosis.

The effect of different salivary calcium concentrations on the erosion protection conferred by the salivary pellicle

Different proportions of mineral ions in saliva can influence the protective effect the salivary pellicle provides against dental erosion. To investigate the effect of different calcium concentrations in human saliva on the protection against enamel erosion, enamel specimens were divided into 8 treatment groups: humid chamber (Ctrl); whole mouth stimulated human saliva (HS); artificial saliva containing different calcium concentrations (ASlow, ASmedium, AShigh); and dialysed human saliva containing different calcium concentrations (DSlow, DSmedium, DShigh). The specimens underwent 4 cycles of incubation in the treatment group followed by an erosive challenge. Surface hardness and calcium release were measured during the cycling process. All DS groups exhibited significantly higher enamel surface softening than HS and the corresponding AS groups. Among the DS groups, the surface softening was significantly higher in DSlow than in DShigh. No significant differences were found within the AS or DS groups regarding calcium release. The results of this study indicated that erosion protection conferred by saliva depends on an interplay between salivary proteins and ions. While both proteins and ions have a positive effect on their own, the combination of the two can lead to different degrees of protection or even negative effects, depending on the relative concentrations.

EFFECT OF DIFFERENT CALCIUM CONCENTRATIONS IN SOIL ON SURVIVAL PERCENT AND UPTAKE OF Na+ AND Cl- IONS BY RICE PLANT

Salinity is a stress factor affecting the production of crop in many regions.  Calcium can reduce Na+ transport to shoots in rice. Two greenhouse experiments were conducted in Faculty of Agriculture, Cairo University, Egypt, during 2015 growing season of rice to evaluate the effect of different calcium concentrations on survival percent along with uptake of Na+ and Cl- ions by two varieties of rice (Oryza sativa L.) differing in salt-tolerance. The first experiment was undertaken to study the effect of different calcium concentrations on survival percent of IR28 (salt-sensitive) and Nona Bokra (Salt-tolerant) seedlings which were transferred to salinized nutrient solution containing 0.5% NaCl and a variable calcium concentrations at 4, 40, 100 and 200 ppm; plants were grown up to 40 days. The second experiment investigated the effect of different calcium concentrations on growth, uptake and transport of Na+ and Cl- ions in the two rice varieties differing in salt-tolerance. The seedlings were transferred to salinized nutrient solution containing 0.5% NaCl and calcium ion concentrations at two levels, 4 and 40 ppm. Plants were harvested at 0, 1, 3, 5 and 7 days from salinization. The results indicated that the salt-tolerant variety (Nona Bokra) survived for more than 40 days under exposure to 0.5% NaCl when calcium concentration of the culture solution ranged from 40 to 200 ppm Ca++. The low calcium ion concentration (4 ppm) depressed the growth of plants at 5 and 7 days after salinization.  In Nona Bokra, the shoot had less sodium and Cl than the root. This implies that the salt tolerance of Nona Bokra may be attributed to the restricted translocation of Na+ and Cl- from the root to the shoot. Sodium as well as cloride content in the shoot of IR28 was more than twice that of Nona Bokra.  An adequate amount of Ca+2 tended to lower the salt injury caused by high levels of salinity in rice plants. The effect of calcium ion on salt tolerance varied greatly between Nona Bokra and IR28 varieties.

Effect of calcium on porcine ICSI embryos expressing EGFP is related to activation of ooplasmic DNase I

Several reliable methods to produce transgenic animals use the male genome. After penetration into oocytes, sperm DNA undergoes dramatic conformational changes that might represent an opportunity for exogenous DNA to integrate into the zygote genome. A nuclease, DNase I, with Ca 2+ /Mg 2+ dependent activity and Zn 2+ inhibition, is one of the enzymes responsible for sperm DNA remodeling. To date, the effect of different calcium concentrations in manipulation media on porcine intracy- toplasmic sperm injection has not been fully investigated. The present study was conducted to examine the effect of calcium in the surrounding media, and we found that the number of embryos expressing green fluorescent protein (EGFP) was increased in media containing Ca 2+ . How- ever, the number did not change over Ca 2+ concentrations from 2 to 8 mmol$L -1 (P>0.05). Moreover, free Ca 2+ concentrations in the media were found to affect the efficiency which is porcine intracytoplasmic sperm injec- tion (ICSI) embryos expressing EGFP protein, which was related to the activation of ooplasmic DNase I. These findings reveal a mechanism and pathway involving EGFP expression in ICSI embryos.

Phenotypic shift of adipocytes by cholecalciferol and 1α,25 dihydroxycholecalciferol in relation to inflammatory status and calcium content.

Recent experimental data seem to suggest a relevant role for 1,25[OH]2cholecalciferol (1,25[OH]2D3) in adipocyte physiology and pathophysiology, with some studies showing adipogenic and pro-inflammatory properties, and others lipolytic and anti-inflammatory functions. Moreover, to our knowledge, the role of cholecalciferol (D3) in adipocytes function is still not known. Therefore, the aim of this study was to investigate in vitro the effects of 1,25[OH]2D3, as well as of D3, in 3T3-L1 adipocytes in basal and inflammatory conditions, testing the effects of different calcium concentrations in adipocytes culture medium. In 3T3-L1 adipocytes, CYP27A1 and CYP27B1 mRNA were detected in basal conditions and induced after D3 treatment. Pre-treatment of 3T3-L1 adipocytes not only with 1,25[OH]2D3, but also with D3 before inflammatory stimulation, significantly prevented the increase in gene expression and protein secretion of IL-6 and TNF-α, and significantly increased IL-10 mRNA and protein production compared with adipocytes treated only with lipopolysaccharide (LPS). Biological effects of D3 were still present after inhibition of P450 activity with ketokonazole. LPS determined a decrease in cell area compared with controls, paralleled by a significant increase in optical density (OD) of lipid droplets, whereas 1,25[OH]2D3 and D3 alone significantly increased adipocytes area and decreased OD. Pretreatment with both forms of vitamin D preserved cells from the reduction in their area observed after LPS treatment. LPS decreased more the area of cells grown in a high calcium medium than of adipocytes grown in a low calcium medium. In the presence of a high calcium medium, 1,25(OH)2D3 treatment preserved cell area, maintaining its anti-inflammatory and adipogenic properties. In conclusion our results show that D3, besides 1,25[OH]2D3, presents anti-inflammatory effects on 3T3-L1, as well as that adipocytes have the enzymatic pathways necessary to locally regulate the production of active forms of vitamin D, capable of influencing adipocyte phenotype and function.

Kinetic characterization of Ca2+-ATPase (SERCA1) inhibition by tri-n-butyltin(IV) chloride. A docking conformation proposal

Organotin compounds, such as tri-n-butyltin(IV) chloride (TBT), are widespread toxicants which disrupt different functions in living organisms. TBT interacts with lipid membranes and membrane proteins. The inhibition of the calcium ATPase from sarcoplasmic reticulum membranes by TBT was studied. It was found that the ATPase inhibition could not be reverted in a large time scale; moreover, an excess of TBT over enzyme did not fully inhibit the ATPase activity; therefore, it was concluded that TBT irreversibly inhibits the enzyme, and this inhibition is accompanied by a decrease in the effective TBT concentration. The residual ATP hydrolysis activity was measured at different TBT concentrations with time, and the protective effect of different calcium concentrations on the TBT inhibition was also determined. The simplest kinetic mechanism to successfully explain all the observations and the kinetic behavior was found to be a single irreversible step of the inhibitor binding to the enzyme accompanied with a first-order inhibitor inactivation. A fluorescence study of fluorescein-5-isothiocyanate-labeled enzyme revealed that TBT binding to the enzyme entails a conformational change related to the high- to low-affinity calcium-binding state transition (E1 to E2 transition), resembling the conformational change induced by vanadate linked to the formation of E2 V complex from E1 state. A docking study allowed us to propose a binding pocket for TBT in the membrane region of E1 close to the high-affinity calcium-binding sites, as well as to define the interactions with amino acid residues interfering with calcium sites occupancy.

Effects of Different Calcium Concentrations Supplemented on the Diet ofPartula gibbaon their Morphometric Growth Parameters, Weight and Reproduction Success

Partula gibba, commonly known as the Fat Guam Partula, is endemic to Guam and Northern Mariana Islands, and it is listed as endangered in the IUCN Red List of Threatened Species. The effects of calcium concentration on its growth and reproductive success were studied.The snails were divided into six groups, fed ad libitum on a diet based on the one formulated by Frame and Clarke at the Nottingham University approximately 25 years ago or variants in which cuttlebone was substituted by various concentrations of calcium carbonate. Shell height, thickness and width, aperture/lip height and width where recorded every month for a whole year, and all were found to be significantly positively correlated with the percentage of added calcium carbonate in the diet (range 0–40% dry wt:wt). Morphometric growth parameters of snails fed 20% added calcium carbonate did not differ significantly from the diet with added cuttlebone (20%), with the exception of their reproductive success, which was lower with the cuttlebone treatment. Reproduction success (expressed by the number of newborns per adult per month) was also significantly and positively correlated over the range of added calcium carbonate to the diet.

Optimal Concentration of Calcium and Electric Field Levels Improve Tetraploid Embryo Production by Electrofusion in Mice

Polyploid embryo production is an important technique in generating mice directly from embryonic stem (ES) cells. The present study was designed to assess the effect of different calcium concentrations and electric field intensities on the production of tetraploid embryos with higher developmental potential by electrofusion. Two-cell mouse embryos were electrofused in fusion solution containing different concentrations of calcium ion (0.05, 0.1, 0.2, 0.4, 0.6, 0.8, 1.0, 1.2 and 1.4 mM). The rates of blastomere fusion, and subsequent cleavage and development of tetraploids to the blastocyst stage were highest when two-cell embryos were electrically stimulated in a fusion medium containing 1.0 mM calcium. Therefore, we tested electric field intensities (0.6, 0.8, 1.0, 1.2 and 1.4 kV/cm) for electrofusion of two-cell embryos and subsequent development to the blastocyst stage in 1.0 mM calcium. The highest rates of fusion and blastocyst formation were observed when the electric field strength was 0.8 kV/cm. The present results showed that mouse two-cell embryos stimulated with 0.8 kV/cm in a fusion medium containing 1.0 mM calcium had the highest rates of fusion and development to the blastocyst stage.

Cobalt uptake across the gills of the common carp, Cyprinus carpio, as a function of calcium concentration in the water of acclimation and exposure

The effect of different calcium concentrations on the uptake of cobalt through the gills of the common carp, Cyprinus carpio , was studied in chemically defined freshwater. Prior to the cobalt uptake experiments, fish were acclimated for 16 days to different calcium concentrations ranging from 100 to 10,000 μM calcium. Co 2+ uptake experiments were conducted over a 3-hr period at the same range of calcium concentrations. There is a clear decrease in the uptake of Co 2+ with increasing calcium concentrations in the exposure water. Above a calcium concentration of 1000 μM, no effect on Co 2+ uptake is observed. The effect of the calcium concentration in the acclimation water is significant, but of minor importance. The rate of Ca 2+ uptake in gills and blood did not depend on the amount of calcium present in the water. Results of this study suggest that the effect of calcium on Co 2+ uptake involves a direct interaction with the systems involved in the translocation of these metal ions across the gill epithelium.

The effect of calcium on cardiac anaphylaxis in guinea-pig Langendorff heart preparations

This study was designed to determine the effects of different calcium concentrations on the perfused isolated guinea-pig heart preparation subjected to cardiac anaphylaxis. Following challenge both physiological and biochemical effects were determined on hearts from guinea-pigs previously sensitized to ovalbumin. Perfusion media containing either 1,2.54 or 5 mM of calcium was used. In comparison to nonsensitized controls challenged to ovalbumin, challenged sensitized hearts (CSH) perfused with 1 mM Ca2+ showed an initial increase in dF/dt, a prolonged rise in H.R. and depressed coronary flow. Raising the calcium concentration to either 2.54 or 5 mM in CSH preparations resulted in a marked increase in the release of lactate dehydrogenase (LDH) into the coronary effluent and depressed coronary flow. Perfusing CSH preparations with increasingly higher calcium concentrations more often produced severe tachyarrhythmias and fibrillation. The highest level of histamine released into the coronary effluent occurred immediately following challenge and then declined exponentially over the next 20 min. Both challenge and the administration of histamine induced an immediate but transient increase in H.R., a rise in dF/dt, and LDH release. The infusion of histamine produced an increase in coronary flow, but on porcine tubular coronary arterial segments only a direct constricting effect was obtained. The prior administration of cimetidine (10(-5) M) attenuated the rise in LDH and dF/dt in CSH and nonsensitized preparations infused with histamine (3 micrograms). However, although cimetidine did not affect the decreased coronary flow in CSH preparations, it initially attenuated the rise in coronary flow in preparations infused with histamine. These results suggest that calcium enhances the likelihood of tachyarrhythmias in cardiac anaphylaxis. The release of LDH in histamine-infused preparations and those CSH preparations perfused with 2.54 and 5 mM calcium-containing media also suggests the possibility that calcium enhances the damaging effects on the myocardial cell in cardiac anaphylaxis.

P-197) - The effects of different calcium concentrations on the inhibitory potency of noradrenaline in the synaptic transmission of the guinea-pig hypogastric ganglion

P-197) - The effects of different calcium concentrations on the inhibitory potency of noradrenaline in the synaptic transmission of the guinea-pig hypogastric ganglion

THE EFFECT OF DIFFERENT CALCIUM CONCENTRATIONS ON THE INHIBITORY EFFECT OF PRESYNAPTIC α‐ADRENOCEPTORS IN THE RAT VAS DEFERENS

The effects of different calcium concentrations on the twitch-inhibitory potency of clonidine and of guanethidine have been examined in the rat isolated vas deferens. Vasa deferentia did not respond to field stimulation at 0.3 Hz in Krebs solution containing 0.325 mmol/1 of calcium. Increasing the calcium concentration to 5.2 mmol/1 caused a concentration-dependent increase in size of the twitch response. The twitch inhibitory potency of clonidine was inversely proportional to the calcium concentration. The inhibitory effect of guanethidine was not influenced by changes in calcium concentration. The results show that the modulation of motor function by presynaptic alpha-adrenoceptors in the rat vas deferens is calcium-dependent.

THE EFFECT OF CALCIUM AND DIBUTYRYL-cAMP ON THE SECRETION OF PARATHYROID HORMONE BY HUMAN PARATHYROID ADENOMAS IN ORGAN CULTURE

The effect of different calcium concentrations as well as dibutyryl-cyclic adenosine 3',5'-monophosphate (DB-cAMP) on the secretion of parathyroid hormone by human parathyroid adenomas taken from patients with primary hyperparathyroidism (pHPT) was studied in organ culture. Their influence on the release of hormone was determined. The tissue was incubated in culture medium for 4 h; the medium was changed hourly and analyzed for immunoreactive parathyroid hormone (PTH) by radioimmunoassay. The hormone secretion showed an inverse relationship to different calcium concentrations in the medium and could be stimulated independently of the calcium concentration by adding DB-cAMP. These results suggest that the examined parathyroid adenomas are sensitive to physiological stimuli.