Calcium And Phosphorus Research Articles

Destruction of cariogenic biofilms by antimicrobial photodynamic therapy mediated by phycocyanin and toluidine blue along with sodium fluoride varnish or titanium tetrafluoride

ObjectiveEvaluation of the effect of phycocyanin (PC) and toluidine blue (TBO) along with sodium fluoride varnish (FV) or titanium tetrafluoride (TiF4) under the conditions of antimicrobial photodynamic therapy (PDT) on a dual-species cariogenic biofilm and on remineralization process. DesignAfter the development of Streptococcus mutans and Lactobacillus acidophilus dual-species biofilms on the human enamel disks, they were divided into 11 groups (n = 9): Control (0.9 % saline), PC, TBO, FV, and TiF4 alone, PC and TBO in combination with a 635 nm diode laser (PDT treatment), PC-PDT+ (PC + FV or TiF4 + 635 nm diode laser), and TBO-PDT+ (TBO + FV or TiF4 + 635 nm diode laser). After the treatment, crystal violet assay was performed to determine the reduction of cariogenic biofilms. Enamel remineralization changes were analyzed using energy dispersive X-ray spectroscopy (EDX) and field emission scanning electron microscopy (FESEM) for the calcium and phosphorus (Ca/P) ratio. ResultsOnly TBO-PDT+ showed superior antibiofilm activity when TiF4 was applied. Furthermore, the highest Ca/P ratio was found after treatment of enamel surfaces with TiF4-TBO-PDT+. The FESEM images showed that the enamel disks treated with TiF4 plus TBO-mediated PDT exhibited surface coating. However, TiF4 plus PC-mediated PDT cannot repair demineralized enamel. ConclusionsThese data suggest that TBO-PDT along with TiF4 can effectively reduce cariogenic biofilms and significantly remineralize enamel disks, opening new avenues in caries prevention.

Ultrastructural studies on implants failure with immediate or late loading

Objectives. The purpose of the present study was to evaluate by scanning electron microscope (SEM) and energy dispersive spectrophotometry (EDS), the degree of bone mineralization of the tissues on the surface of failure dental implants with immediate or late loading. Materials and method. In the study, 8 dental explants from 8 clinically healthy, non-smoking patients were taken. All implants were inserted by the same dental surgeon, 4 of them were immediate loaded and 4 were late prosthetically loaded by the same dentist. The ablation of the implants was performed as atraumatically as possible and they were collected in sterile containers and sent to the BIOMAT Research Center, where they were subjected to SEM and EDS analyses. The ratios between the chemical elements calcium and nitrogen (Ca/N), phosphorus and nitrogen (P/N), respectively calcium and phosphorus (Ca/P) were calculated for each of the 8 samples and were statistically analyzed. Results. If we compare the degree of coverage of the implants with bone tissue in different phases of mineralization, we find that the bone structures occupy a larger surface area of the implants in the cases with immediate loading compared to the cases with late loading. Thus, out of 4 immediately loaded implants, 2 were completely covered, one showed very little exposed areas, and the fourth showed alternating covered and uncovered areas. Regarding the late loaded implants, three showed alternation between covered and uncovered areas and only one was completely covered with bone. Conclusions. The degree of coverage of the explants with bone tissue was better represented for the immediate loading cases. The degree of mineralization of the bone tissue covering the explants was higher for cases with immediate loading. To confirm the obtained results, it is necessary to expand the study on larger batches of samples.

Relationship between low vitamin D levels with Hashimoto thyroiditis

Introduction/Objective. Vitamin D not only plays a role in calcium and phosphorus metabolism, but also has antiproliferative, prodifferentiation, anti-inflammatory and immunomodulatory effects. The aim of this study was to investigate the association between vitamin D deficiency in individuals with autoimmune Hashimoto?s thyroiditis. Methods. A total of 156 patients were enrolled and divided into two groups. First group included 108 patients with 25 (OH) D insufficiency, and second included 48 individuals with normal 25 (OH) D levels. All participants underwent a detailed clinical examination, laboratory tests for thyroid function [T3, fT4, TSH, thyroid antibodies (TPO-Ab, and TG-Ab)], as well as ultrasound scanning (thyroid volume and Doppler characteristics). Results. The patients with vitamin D insufficiency (n = 108 (69.2%)) were predominantly female and had a higher body mass index than the patients with normal vitamin D levels. The group with vitamin D insufficiency had statistically significantly higher TSH levels. The prevalence of positive thyroid antibodies was higher in the vitamin D insufficiency group, while thyroid volume, superior thyroid artery, and inferior thyroid arteries resistance index, as well as the prevalence of positive circular dichroism signals, were significantly higher in the vitamin D insufficiency group. Out of the 156 subjects, 44 were diagnosed with thyroiditis (28.2%). The mean serum level of 25 (OH) D was statistically notably lower in patients with thyroiditis (20.23 ? 8.10 ng/mL) than in the group without thyroiditis (25.44 ? 8.38 ng/mL), p < 0.001. Conclusion. There was an association between vitamin D insufficiency and hypothyroidism in subjects with Hashimoto?s thyroiditis.

Ameliorative impacts of sodium humate on heat-stressed laying Japanese quail (Coturnix coturnix Japonica).

A total of 300 laying Japanese quails (230.10 ± 20 g body weight) divided into fourgroups (15 birds in 5 replicates/group) were used to examine the impacts of dietary sodium humate (SH) supplementation at levels of 0% (control diet), 0.2%, 0.4%and 0.6% on egg variables and physiological merits of laying quails for 10 weeks under heat stress conditions (15Juneand 23August 2021). Results showed 0.4% SH increased (p < 0.05) weight (12.27 vs. 11.91 g), production (79.84% vs. 69.20%), mass (597.13 vs. 510.48 g)and brokenness (2.8% vs. 5.4%) of eggs as compared to control. Egg shape, shell thickness, shell strengthand cholesterol content as well as feed conversion ratio were higher (80.2, 295.8 µm, 1.468 kg/cm,2 11.08 mg/gand 2.69, p < 0.05) in 0.4% SH than in control group (75.2, 279.0 µm, 1.304 kg/cm,2 14.94 mg/gand 2.76). Feed intake, percentages of eggs' shells, yolk, albumenand serum biochemistry (total protein, albumin, ASTand HDL) were not altered with the dietary SH. Birds fed on SH diets showed higher levels of globulin, calciumand phosphorus, as well as lower contents of albumin/globulin ratio, triglycerides, cholesterol, corticosterone compared with the control. Regression analysis of antioxidants expected higher total antioxidant capacity (TAC), superoxide dismutase, glutathione peroxidase at 0.35%, and glutathioneat 0.40% SH, while the lowest concentration of malondialdehydewas computed at 0.45%. Similarly, immunoglobulins (IgG and IgM) maximum values were determined at 0.35% and 0.40% levels. Moreover, the concentration of tumour necrosis factor-alphaincreased (p < 0.05) in all SH levels as compared to the control group. It is conceivable to conclude that the dietary implementation of SH at a level of 0.4% improved egg variables and well-being aspects of laying quail exposed to heat stress conditions.

Nanoporous Titanium Enriched with Calcium and Phosphorus Promotes Human Oral Osteoblast Bioactivity.

Implant surfaces are known to influence the osseointegration process; therefore, their modifications represent an important subject of investigation. On this basis, the purpose of this study was to evaluate the response of human oral osteoblasts (hOBs) to three different GR4 titanium discs: Machined, double-etched (Osteopore), and double-etched, surface-enriched with calcium and phosphorus (CaP) (Nanopore). The superficial topography was investigated with scanning electron microscopy (SEM) and the sessile drop technique. To test cellular response and osteoinductive properties, the following points were evaluated: (i) proliferation by MTS assay after 2 and 5 days; (ii) adhesion by multiphoton microscopy at day 2; (iii) the interaction with Ti discs by blue toluidine staining at day 5; (iv) alkaline phosphatase (ALP) activity by ALP assay after 14 days; (v) calcium deposition by alizarin red staining and by cetylpyridinium chloride after 14 days. The SEM analysis showed that Nanopore and Osteopore surfaces were characterized by the same micro-topography. Nanopore and Osteopore discs, compared to Machined, stimulated higher osteoblast proliferation and showed more osteoinductive properties by promoting the ALP activity and calcium deposition. In conclusion, the CaP treatment on DAE surfaces seemed to favor the oral osteoblast response, encouraging their use for in vivo applications.

Erosive tooth wear potential of some traditional plant drinks and cola based drinks on human extracted teeth

Background: This study aimed at investigating the pH, titratable acid and erosive tooth wear potentialof some local beverages in Sudan, Adansonia digitata (baobab), Tamarindus indica (tamarind), Hibiscus sabdariffa (hibiscus)) and cola-based drinks.Methods: Twenty extracted premolar teeth were sectioned and treated with tested drinks for 10, 20 and30 minutes representing three consumption frequencies. The pH and titratable acid of drinks were measuredusing a pH meter. Calcium and phosphorus release were recorded as measures for teeth demineralization. Calcium release was determined photometrically, using atomic absorption spectrophotometry, andphosphorus release using the phosphomolybdate-malachite green procedure.Results: Cola- based drinks recorded the lowest pH (1.87) while Hibiscus sabdariffa, the second lowestpH (1.93) and the highest titratable acid (60.12 mmolOH- /L). The local beverages (Adansonia digitata, Tamarindus indica, and hibiscus sabdariffa) showed high levels of calcium as compared to the cola-baseddrinks. There was a correlation between the calcium and phosphorus contents of the drinks and calciumand phosphorus release over different times. The pH of drinks and calcium release correlated significantly.There was no significant association between pH of drinks and phosphorus release and with TA and calciumand phosphorus release.Conclusion: Despite their high nutritive values, local drinks tended to alter the ionic concentration ofteeth when contacting them indicating an erosive potential. Work needs to be supplemented by in-vivo trialsinvestigating factors such as salivary parameters and modes of drinking influencing their erosive potential.

Influence of age and sex on the blood biochemical constituent values of broiler breeders during the egg-laying stage.

This study aimed to evaluate the influence of age and sex on the blood biochemical constituents of broiler breeders during the egg production stage. The analysis was performed in an industrial broiler breeder farm, and blood samples were collected from males and females at five different ages. Biochemical elements analysed in each serum sample were total proteins, albumin, globulins, uric acid, total cholesterol and triglycerides, alanine aminotransferase (ALT) and aspartate aminotransferase (AST), gamma-glutamyltransferase (GGT), creatine kinase (CK), alkaline phosphatase (PAL), calcium and phosphorus, beside the glycaemic status. At most ages, females had higher values of total proteins, albumin, globulins, triglycerides, cholesterol, glucose, calcium, phosphorus, Ca/P (calcium and phosphorus) ratio and gamma-glutamyltransferase (GGT). The values of uric acid, aspartate aminotransferase (AST), creatine kinase (CK) and alkaline phosphatase (PAL) were higher in males. The lowest protein values were found at 28 and 60 weeks old. The mean albumin values were significantly higher at 44 and 52 weeks old in males and females. A trend of increasing globulin values with increasing age up to 52 weeks old was observed. Although calcium and phosphorus did not vary according to age, the Ca/P ratio was lowest at 36 weeks old. Comparing the means of both sexes, the AST and GGT values were significantly higher in 60-week-old birds. The highest serum levels of CK occurred at 28 and 52 weeks old. The physiological levels of serum biomarkers presented in this work are important for evaluating productivity performance, welfare and disease indication in breeding flocks.

Research Progress on the Relationship between Polymorphism and SLE of Vitamin D Metabolic Pathway Related Gene

Vitamin D is a class of hormones necessary to maintain normalphysiological activities of the body. A large number of studies have shownthat vitamin D, as a fat-soluble vitamin, is not only related to calcium andphosphorus metabolism, but also closely related to immune regulation,humoral regulation, cell cycle and so on. Systemic Lupus erythema-Tosus(SLE) is a specific autoimmune diffuse connective tissue disease thatcauses tissue and organ damage under the joint action of multiple factorssuch as environment and heredity. Among many factors, the vitamin Dmetabolism pathway gene is particularly important for its influence. Someliterature has shown that the genetic polymorphism of vitamin D metabolicpathway genes is correlated with SLE. Therefore, by referring to relevantliterature, this paper summarized the progress in the research on themechanism of genetic polymorphism of vitamin metabolism pathway genesand the development of SLE.

Vitamin D Supplementation Efficacy and Its Relationship to Grip Strength and Gait Speed in the Oldest Olds with Functional Dependence

Vitamin D is a well-known regulatory factor, not only in calcium and phosphorus homeostasis, but also in extraskeletal actions...

Joint Longitudinal Low Calcium High Phosphorus Trajectory Associates with Accelerated Progression, Acute Coronary Syndrome and Mortality in Chronic Kidney Disease

The effects of long-term disturbance of the mineral metabolism on patients with chronic kidney disease (CKD) are unclear. We investigated whether the longitudinal Ca-P (joint calcium and phosphorus) trajectories are associated with incident end-stage renal disease (ESRD), acute coronary syndrome (ACS), and all-cause mortality in patients with CKD. We conducted a prospective cohort study by using data from a 13-year multidisciplinary pre-ESRD care registry. The final study population consisted of 4,237 CKD patients aged 20–90 years with data gathered from 2003 to 2015. Individuals’ Ca-P trajectories were defined using group-based multi-trajectory modeling into three distinct patterns: reference, moderately abnormal, and severely abnormal. Times to ESRD, ACS, and death were analyzed using multiple Cox regression. Compared with those with a “reference” Ca-P trajectory, the adjusted hazard ratios (aHRs) (95% confidence interval [CI]) for incidental ESRD were 5.92 (4.71–7.44) and 15.20 (11.85–19.50) for “moderately abnormal” and “severely abnormal” Ca-P trajectories, respectively. The corresponding aHRs for ACS were 1.94 (1.49–2.52) and 3.18 (2.30–4.39), and for all-cause mortality, they were 1.88 (1.64–2.16) and 2.46 (2.05–2.96) for “moderately abnormal” and “severely abnormal” Ca-P trajectories, respectively. For outcomes of progression to ESRD, the detrimental effects of abnormal Ca-P trajectories were more substantial in patients with CKD stage 3 than those with CKD stage 4 or 5 (p-value for interaction < 0.001). Future studies should validate reliable longitudinal cut-offs of serum phosphorus and consider the “lowering phosphorus— the lower the better, the earlier the better” approach to phosphorus control in CKD.

Therapeutic Value of Vitamin D as an Adjuvant Therapy in Neonates with Sepsis

The current study aimed to evaluate the therapeutic value of vitamin D supplementation as an adjuvant therapy in neonates with sepsis. This study included 60 neonates with sepsis who were randomly divided into 2 equal groups; group I: 30 neonates with sepsis who received antibiotic only, Group II: 30 neonates with sepsis who received antibiotic therapy and vitamin D. This study also included 30 healthy neonates as a control group. For all patients and controls, serum level of 25 (OH) vitamin D and highly sensitive C reactive protein (hs-CRP) were immunoassayed. There is no significant difference between groups I, II and controls regarding weight, gestational age, sex and mode of delivery. There were significant differences between groups I and II in sepsis score and hs-CRP after 3, 7, 10 days of treatment (p values for sepsis score were 0.009, 0.006, 0.004 respectively and for hs-CRP were 0.015, 0.001, 0.001 respectively). There was a significant difference in immature /total (I/T) ratio after 7, and 10 days of treatment (p value= 0.045, 0.025, respectively,) while there was no significant difference in immature /total (I/T) ratio after 3 days of treatment (p value = 0.624).Serum 25(OH) vitamin D levels were significantly lower in neonates with sepsis (group I and II) than the controls (p value < 0.05, while there were no significant differences between the three groups considering serum calcium and phosphorus levels (P =1.000, 1.000, respectively). Isolated organisms from blood culture in neonates with sepsis (group I and group II) were most commonly B- hemolytic streptococci, E-coli, hemophilus influenza and staphylococcus aurous. There was a significant negative correlation between hs-CRP and serum 25 (OH) vitamin in group II on entry (r = - 0.832 and P value = 0.001) and after 2 weeks (r = - 0.590 and P value = 0.021). ROC curve of specificity and sensitivity of 25 (OH) vitamin D level in prediction of early-onset neonatal sepsis showed that cutoff value of vitamin D was ≤20 ng/ml, sensitivity was 100%, specificity was 73%, positive predictive value was 73%, negative predictive value was 100% and accuracy was 87. Serum 25 (OH) vitamin D levels of neonates with the early onset neonatal sepsis were significantly lower than the healthy controls. Vitamin D supplementation improved sepsis score and decrease high levels of hs-CRP; this reflects the role of vitamin D as a target therapy for neonatal sepsis. Further studies are warranted to confirm the therapeutic value of vitamin D in neonatal sepsis.

STRONTIUM CONTENT IN SANDY SOILS IN AGRICULTURE FIELDS (CASE STUDY: MOUNDOU, CHAD)

During evaluation of physical and chemical properties of sandy soils and theirfertility in Southern part of Republic of Chad it has been revealed that some soilshave very high content of strontium. Its content varies from 10 to 270 mg/kg ofsoil depending on type of soil, depth of soil layers, clay and organic content.Strontium content negatively correlates with total content of calcium andphosphorus in layers of soil. Low CEC (CEC - Cation-exchange capacity) of soilmay be a reason of possible translocation of strontium from higher to lower layersof soils. Strontium content in soils do not relates with level of radioactivity of soilmeasured. The highest content of strontium has been found in soils developed onsome eolian and colluvio-alluvium deposits. Some researchers hypothesize thatsome endemic and chronic diseases such as Kashin-Beck disease, `Dysostosisenchondralis endemic`, endemic hoiter, osteoarthritis might be caused by highcontent of strontium in water and plant foods contaminated with it. Absence ofconsensus on etiological factors of these diseases confirms that it is worthconsidering necessity of further studies of different affects of high content ofstrontium in water and foods on human health directly or indirectly throughcausing misbalance in mineral nutrition.

Effects of Feed Additives Used As an Alternative to Antibiotics on Mineral Absorption and Bone Characteristics in Poultry: A Review

Calcium and phosphorus are essential minerals for some important biochemical functions and bone integrity. Deficiency in rations or poor absorption of these minerals is an important problem in poultry nutrition, especially high producing laying hens and broilers, leading to economic losses such as deterioration of eggshell and bone characteristics as a result of mineral metabolism disorders. Therefore, maximization of absorption and bioavailability of these nutrients from the gut can be practical for preventing mineral metabolism disorders. Antibiotics widely used as growth promoters for many years in animal nutrition. After the prohibition of antibiotics, the research for alternatives to antibiotics has accelerated. Probiotics, prebiotics and organic acids are some of these alternatives. Most of the earlier studies showed that probiotics, prebiotics, and organic acids increased the mineral absorption and metabolism. In this review, effects of probiotics, prebiotics and organic acids on mineral utilization and bone characteristics in poultry are deliberated.

Effects of Propolis on Oxidative Stress in Rabbits Undergoing Implant Surgery

Abstract Objectives: Implants are the natural or artificial materials that replace a missing tissue or organ. When that missing part is one or more teeth, there is a need for the reconstructive material that supports prosthetic restoration, which is called dental implant. Many local and general factors affect bone healing. Recent studies show that, free radicals are among the factors that affect the bone healing. This study is planned presuming propolis could have positive effects on oxidative stress and bone healing after implantation due to its antioxidant nature, its effects on accelerating the bone formation, wound healing and increasing the bone density. Materials and Methods: 24 New Zealand white rabbits were used in the study. Animals were divided into 3 groups, each consisting of 8 rabbits. Implants were placed into the proximal region of tibia unilaterally. Propolis was applied to slots before placing the implants on local group and systemically applied after implantation on systemic group. Results: SOD activity was increased in both propolis groups compared to control group, but it was not statistically significant. Catalase level of the systemic group was found to be significantly higher. MDA level in serum, which indicates lipid peroxidation, was significantly lower in both propolis groups compared to control group. Reduced GSH concentration in granulation tissue was increased in rabbit groups treated with propolis compared to control group. There were no significant differences in calcium and phosphorus values, however it can be said that there is a significant increase in vitamin D amount of local and systemic groups. Conclusion: Propolis has antioxidant, antimicrobial and many other biological activities. Due to the features that it has, propolis has a positive effect on osseointegration and bone healing. The comparison of systemic and local group showed that, systemically given propolis provided better results than local application.

Dietary changes in nutritional studies shape the structural and functional composition of the pigs\u2019 fecal microbiome\u2014from days to weeks

BackgroundThe possible impact of changes in diet composition on the intestinal microbiome is mostly studied after some days of adaptation to the diet of interest. The question arises if a few days are enough to reflect the microbial response to the diet by changing the community composition and function. The present study investigated the fecal microbiome of pigs during a time span of 4 weeks after a dietary change to obtain insights regarding the time required for adaptation. Four different diets were used differing in either protein source (field peas meal vs. soybean meal) or the concentration of calcium and phosphorus (CaP).ResultsTwelve pigs were sampled at seven time points within 4 weeks after the dietary change. Fecal samples were used to sequence the 16S rRNA gene amplicons to analyse microbial proteins via LC-MS/MS and to determine the SCFA production. The analysis of OTU abundances and quantification values of proteins showed a significant separation of three periods of time (p = 0.001). Samples from the first day are used to define the ‘zero period’; samples of weeks 1 and 2 are combined as ‘metabolic period’ and an ‘equilibrium period was defined based on samples from weeks 3 and 4. Only in this last period, a separation according to the supplementation of CaP was significantly detectable (p = 0.001). No changes were found based on the corn-soybean meal or corn-field peas administration. The analysis of possible factors causing this significant separation showed only an overall change of bacterial members and functional properties. The metaproteomic approach yielded a total of about 9700 proteins, which were used to deduce possible metabolic functions of the bacterial community.ConclusionsA gradual taxonomic and functional rearrangement of the bacterial community has been depicted after a change of diet composition. The adaptation lasts several weeks despite the usually assumed time span of several days. The obtained knowledge is of a great importance for the design of future nutritional studies. Moreover, considering the high similarities between the porcine and human gastrointestinal tract anatomy and physiology, the findings of the current study might imply in the design of human-related nutritional studies.

Changes in Biochemical Parameters of the Calcium-Phosphorus Homeostasis in Relation to Nutritional Intake in Very-Low-Birth-Weight Infants.

Preterm infants are at significant risk to develop reduced bone mineralization based on inadequate supply of calcium and phosphorus (Ca-P). Biochemical parameters can be used to evaluate the nutritional intake. The direct effect of nutritional intake on changes in biochemical parameters has not been studied. Our objective was to evaluate the effect of Ca-P supplementation on biochemical markers as serum (s)/urinary (u) Ca and P; alkaline phosphatase (ALP); tubular reabsorption of P (TrP); and urinary ratios for Ca/creatinin (creat) and P/creatinin in Very-Low-Birth-Weight infants on Postnatal Days 1, 3, 5, 7, 10, and 14. This observational study compared two groups with High (n = 30) and Low (n = 40) intake of Ca-P. Birth weight: median (IRQ) 948 (772–1225) vs. 939 (776–1163) grams; and gestational age: 28.2 (26.5–29.6) vs. 27.8 (26.1–29.4) weeks. Daily median concentrations of biochemical parameter were not different between the groups but linear regression mixed model analyses showed that Ca intake increased the uCa and TrP (p = 0.04) and decreased ALP (p = 0.00). Phosphorus intake increased sP, uP and uP/creat ratio and ALP (p ≤ 0.02) and caused decrease in TrP (p = 0.00). Protein intake decreased sP (p = 0.000), while low gestational age and male gender increased renal excretion of P (p < 0.03). Standardized repeated measurements showed that biochemical parameters were affected by nutritional intake, gestational age and gender.

Analysis of the mineral composition of hypomineralized first permanent molars.

Hypomineralization of molars and incisors (molarincisor hypomineralization--MIH) is defined as enamel hypomineralization of systemic origin of one or more of the four first permanent molars, which may be associated with changes in the maxillary, and less frequently in the permanent mandibular in cisors. The aim of this study was to investigate the mineral content in hypomineralized teeth as a contribution to understanding the origin of these changes, which will be important for effective restorative approach. A total of 10 extracted first permanent molars diagnosed with MIH were used in the study as the experimental group, and intact first premolars extracted for orthodontic reasons were used as the control group. A certain surface of hypomineralized and healthy enamel and dentin was analyzed using a scanning electron microscope equipped with an energy-dispersive spectrometer (SEM/EDS). By conducting quantitative chemical analysis of the distribution of the basic chemical elements, it was found that the concentration of calcium (Ca) and phosphorus (P) was significantly higher in healthy enamel (Ca = 28.80 w%, and P = 15.05 wt%) compared to hypomineralized enamel (Ca = 27.60 wt% and P = 14.32 wt/o). Carbon (C) concentration was statistically significantly higher in hypomineralized enamel (C = 11.70 wt%) compared to healthy enamel (C = 10.94 wt%). Hypomineralized and healthy enamel did not differ significantly regarding the ratio of calcium and phosphorus concentrations whereas the ratio of calcium and carbon concentrations was statistically significantly higher in healthy enamel compared to hypomineralized enamel. Concentration of the main chemical elements, primarily calcium and phosphorus, is significantly reduced in hypomineralized enamel whereas carbon concentration is increased compared to healthy enamel.

The porosity and roughness of electrodeposited calcium phosphate coatings in simulated body fluid

Calcium phosphate coatings were electrochemically deposited on titanium from the aqueous solution of Ca(NO3)2 and NH4H2PO4 with the current density of 10 mA cm-2 for deposition time of 15 min. The obtained brushite coatings, (CaHPO4?2H2O), were converted to hydroxyapatite (HA) by soaking in simulated body fluid (SBF) for 2, 7 and 14 days. The brushite and hydroxyapatite coatings were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM). It was shown that the increase in soaking time increases the porosity, roughness and crystallite domain size of HA coatings and decreases the unit cell parameters and unit cell volume, while does not affect the HA mean pore area. The calcium and phosphorus ions concentrations in SBF were determined by atomic absorption spectroscopy (AAS) and UV-Vis spectroscopy, respectively and the mechanism of HA growth based on dissolution-precipitation was proposed.

Balanços nutricionais e excreção de nutrientes para frangos alimentados com dietas contendo fitase do 14.o ao 24.o dias de idade

Objetivou-se com este estudo avaliar o efeito da redução de nutrientes e energia suplementada ou não com fitase para frango de corte na fase 14 a 24 dias de idade no consumo, excreção e balanço de nitrogênio, de cálcio e de fósforo. Foram distribuídos 392 frangos de corte em delineamento inteiramente casualizado, utilizando-se arranjo fatorial 3 x 2 + 1 que consistiram de nível reduzido de cálcio e fósforo; níveis reduzidos de aminoácidos e energia; níveis reduzidos cálcio, fósforo, aminoácidos e energia x com e sem enzima + controle positivo, totalizando sete tratamentos com oito repetições de sete aves por unidade experimental. Nas dietas com fitase utilizou-se 500 FTU de fitase/kg de ração. Os dados foram submetidos à análise de variância e as médias comparadas por contrastes ortogonais através do teste F. Os resultados demonstram que a enzima fitase utilizada permitiu diminuir a quantidade de nutriente e energia das rações, proporcionando redução de 21,34% na excreção de cálcio e balanço de cálcio de 20,16%. Similarmente, reduções das quantidades de excreção de nitrogênio em 7,56% e fósforo em 21,34%, diminuindo a excreção desses nutrientes e aumentando o balanço de nitrogênio e fósforo em 9,41 e 33,94% em média, respectivamente.

Bone turnover markers in medicamentous and physiological hyperprolactinemia in female rats

There is a lack of data on the effects of prolactin on calcium metabolism and bone turnover in hyperprolactinemia of various origins. The aim of this study was to compare the influence of medicamentous and physiological hyperprolactinemia on bone turnover in female rats. Experimental animals (18 weeks old, Wistar female rats) were divided as follows: the group P - 9 rats, 3 weeks pregnant; the group M3-10 rats that were intramuscularly administrated sulpirid (10 mg/kg) twice daily for 3 weeks, the group M6 - 10 rats that were intramuscularly administrated with sulpirid (10 mg/kg) twice daily for 6 weeks, and age matched nulliparous rats as the control group: 10 rats, 18-week-old (C1) and 7 rats, 24 weeks old (C2). Laboratory investigations included serum ionized calcium and phosphorus, urinary calcium and phosphorous excretion, osteocalcin and serum procollagen type 1 N-terminal propeptide (P1NP). Experimental animals in the group P compared to the control group, displayed lower mean serum ionized calcium (0.5 +/- 0.2 vs 1.12 +/- 0.04 mmol/L; p < 0.001); higher mean serum phosphorus (2.42 +/- 0.46 vs 2.05 +/- 0.2 mmol/L; p < 0.05); increased urinary calcium (3.90 +/- 0.46 vs 3.05 +/- 0.58; p < 0.01) and significantly increased P1NP (489.22 +/- 46.77 vs 361.9 +/- 53.01 pg/mL; p < 0.001). Experimental animals in the group M3 had significantly decreased P1NP, compared to the contol group. Prolongated medicamentous hyperprolactinemia (the group M6) induced increased serum ionized calcium (1.21 +/- 0.03 vs 1.15 +/- 0.02 mmol/L; p < 0.001); decreased serum phosphorus (1.70 +/- 0.13 vs 1.89 +/- 0.32 mmol/L; p < 0.001); decreased osteocalcin and P1NP. Physiological hyperprolactinemia does not have such harmful effect on bone metabolism as medicamentous hyperprolactinemia. Chronic medicamentous hyperprolactinemia produces lower serum levels of bone formation markers. Assessment of bone turnover markers in prolongated medicamentous hyperprolactinemia provides an opportunity for earlier diagnosis of bone metabolism disturbances and should be considered as mandatory.