• Journal of Periodontal and Implant Science
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• v.31 no.3
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• pp.513-529
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• 2001

For reconstruction of the bony defect, various artificial substitutes were developed. Among them, there has been a study of calcium phosphate coated bone substitutes for increasing attachment of osteoblasts in vivo. The purpose of this study was to evaluate the effects of serum and platelet-rich plasma (PRP) on calcium phosphate coated culture plate for the initial attachment, proliferation and activity of osteoblasts. After sampling the blood from white rats and concentrating by centrifugation, the amount of attachment of PDGF-BB and $TGF-{\beta}$ on the calcium phosphate coated culture plate was measured. Cultured HOS and ROS 17/2.8 cell was measured on attachment level and proliferation rate of osteoblasts. Alkaline phosphatase activity of HOS and ROS 17/2.8 cell was measured for studying on the activating rate of osteoblast. 1. Counting the amount of platelets of seperated plasma and PRP, the average number of platelets was 177,003 $cell/{\mu}l$ in plasma, and 1,656,062 $cell/{\mu}l$ in PRP, which was about 9 times as high as in plasma. 2. Amount of PDGF-BB deposited at calcium phosphate coated plate had increased by the total amount of plasma and PRP on the culture plate, whereas $TGF-{\beta}$had been deposited on the plate only when treated by $50{\mu}{\ell}$ of PRP(p<0.01). 3. After plating serum and PRP for 3 hours, we attached with HOS and ROS17/2.8 cell for 1 hour and 4 hours. There were no significant difference of the attachment between serum and control group, whereas there were significantly difference of the attachment between depositioning of PRP and control group. 4. After attaching plasma and PRP for 3 hours, cell number has much increased when HOS and ROS17/2.8 cell had been cultured for 48 hours(p<0.05). 5. After attaching plasma and PRP for 3 hours, concentration of alkaline-phosphatase has increased when HOS and ROS17/2.8 cell had been cultured for 48 hours(p<0.01). These results suggested that PRP affected on initial cell attachment rather than proliferation and activation of osteoblasts at calcium phosphate coated plate.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.22 no.2
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• pp.92-98
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• 2012

The co-precipitation technique has been applied to synthesize biphasic calcium phosphate (BCP). $Ca(NO_3)_2{\cdot}4H_2O$, $(NH_4)_2HPO_4$, TEOS and $Mg(NO_3)_2{\cdot}6H_2O$ as the starting materials was used. After the heat treatment of powder crystalline phases HAp and ${\beta}$-TCP analysis showed a mixed phase. The overall spectra appear to have mainly two modes corresponding to characteristic $PO^{3-}_4$ and $OH^-$ groups. After immersion in Hanks' Balanced Salt Solution (HBSS) for 1 week a precipitation started to be formed with individual small granules on the specimen surface. An MTT assay indicated that ionic substituted BCP powders had no cytotoxic effects on MG-63 cells, and that they have good biocompatibility.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.20 no.5
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• pp.237-242
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• 2010

Magnesium-substituted BCP (biphasic calcium phosphate) powders were prepared by incorporating small amounts of magnesium into the structure of different hydroxyapatite (HAp)/${\beta}$-tricalcium phosphate (${\beta}$-TCP) ratios through coprecipitation method. A series of magnesium substitutions ranging from 0, 0.5, and 1.0 wt%, which are comparable to the measured magnesium contents, were performed. The obtained powders were characterized by the following analytical techniques: X-ray diffraction analysis (XRD), Thermo Gravimetric Analyzer (TGA) and Fourier transform infrared spectroscopy (FT-IR). The results have shown that substitution of magnesium in the calcium-deficient apatites resulted in the formation of biphasic mixtures of different HAP/${\beta}$-TCP ratios after heating above $1000^{\circ}C$. The 1.0 wt% magnesiumsubstituted-BCP were soaked in Hank's solutions after 2 weeks to observe the morphology of the biocement, especially needle-like hydroxyapatite crystals and to estimate the length and diameter of nanoneedle crystals.

• Journal of the Korean Ceramic Society
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• v.39 no.9
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• pp.884-889
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• 2002

In order to investigate the calcium phosphate forming ability of nanocrystalline $ZrO_2$ film, we prepared $ZrO_2/Si$ structure by using a chemical solution deposition with a zirconium naphthenate as a starting material. Precursor sol was spin-coated onto the (100)Si substrate and prefired at 500$^{\circ}C$ for 10 min in air, followed by final annealing at 800$^{\circ}C$ for 30 min in air. Crystallinity of the annealed film was examined by X-ray diffraction analysis. Surface morphology and surface roughness of the film were characterized by field emission-scanning electron microscope and atomic force microscope. After annealing, nanocrystalline $ZrO_2$ grains were obtained on the surface of the film with a homogeneous interface between the film and substrate. After immersion for 1 or 5 days in a simulated body fluid, formation of calcium phosphate was observed on $ZrO_2$ film annealed at 800$^{\circ}C$ by energy dispersive X-ray spectrometer. The fourier transform infrared spectroscopy revealed that carbonate was substituted into the calcium phosphate.

• Journal of Nutrition and Health
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• v.29 no.5
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• pp.480-488
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• 1996

This study was performed to investigate the effect of various types of calcium sources on calcium and bone metabolism. Sprague-Dawley male rats weighing approximately 89.3g were divided into 4 groups and fed experimental diets containing 0.5% calcium for 5 weeks. Four different calcium salts were used for the study : calcium phosphate, calcium lactate, calcium gluconate, and calcium carbonate. Food intake showed no significant difference n accordance with the type of calcium salt, but bo요 weight gain and food efficiency were lower in calcium gluconate and calcium carbonate groups. There was significant differences in liver, thymus and epididymal fat pad weight with the of calcium salt ; the calcium gluconate group showed lower values compared to the other groups. Femur and scapular length were higher in calcium lactate and calcium carbonate groups. Wet weight, dry weight, and density of the femur tended to be lower in the calcium gluconate group than the other groups, but this difference was not statistically significant. The calcium content of the other groups. The calcium gluconate group showed higher urinary calcium and lower calcium absorption and balance. In conclusion, calcium and bone metabolism were different according to the type of calcium sources consumed.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1998.11a
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• pp.236-239
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• 1998

This research was performed to check the transport characteristics of heavy metals in contaminated soil, that is, the influence of humic acid and phosphate on transport characteristics of heavy metals was studied. From the results of column mode experiments about heavy metal behavior, the order time to reach breakthrough and equilibrium was soil ＋ humic acid( 20g ) > soil ＋ humic acid ( 5 g ) > soil without Humic acid addition > soil+humic acid( 50g ). It is because the dissolved organic carbon content increased as the soil organic matter content increased. As the phosphate increased, so did the time to reach breakthrough and equilibrium. The order of time was soil + phosphate( 50 mg ) > soil + phosphate( 20 mg ) > soil . phosphate( 10 mg ) > soil without phosphate addition. It is because the phosphate ion worked as alkalinity donor and the calcium ion co-injected worked as the accelerator of coprecipitation of heavy metals.

• Restorative Dentistry and Endodontics
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• v.13 no.2
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• pp.307-322
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• 1988

The purpose of this study is to evaluate the pulpal responses to the base materials such as zinc oxide eugenol cement, calcium hydroxide, zinc phosphate cement, polycarboxylate cement and glass ionomer cement. The 100 caries free dog teeth were devided into 2 groups by remaining dentin thickness (Group A: 0.4-0.6 mm, Group B: 0.8-1.0 mm) and each group were devided into 5 subgroups. The intervals of observation period are 3days, 1 week, 2 weeks, 4 weeks and 8 weeks respectively after experiment. The specimens were fixed with 10% formalin and decalcifed in 5% nitric acid. All specimens were stained with Hematoxylin-Eosin and examined histopathologically. The results were as follows. 1. In group A, atropy or hyperplasia in odontoblasts were seen in zinc oxide eugenol cement, calcium hydroxide and zinc phosphate cement. No changes in odontoblasts were seen in polycarboxylate cement and glass ionomer cement. 2. In group A, increase of predentin were seen in all experimental materials. 3. In group A, vascular congestion were seen in all experimental materials and inflammation were seen on 3 days in zinc oxide eugenol cement, 8 weeks in zinc phosphate cement and hemorrage were seen on 3 days in zinc phosphate cement. 4. In group B, changes of odontoblasts were not seen all experimental materials. 5. In group B, increase of predentin and vascular congestion were seen in all experimental materials but inflammation were not seen.

• Journal of the Korean Ceramic Society
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• v.55 no.5
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• pp.480-491
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• 2018

Calcium phosphates (CaP) were prepared by a wet chemical method. Micro-crystalline dicalcium phosphate (DCPD) was precipitated at $37^{\circ}C$ and pH 5.0 using $Ca(OH)_2$ and $H_3PO_4$. The precipitated DCPD solution was kept at $37^{\circ}C$ for 96 h. Artificial bone cement was composed of DCPD, $Ca(H_2PO_4)_2{\cdot}H_2O$ (MCPM), and $CaSO_4{\cdot}1/2H_2O$, $H_2O$ and aqueous poly-phosphoric acid solution. The wet prepared CaP powder was used as a matrix for the bone cement recipe. With the addition of aqueous poly-phosphoric acid, the cement hardening reaction was started and the CaP bone cement blocks were fabricated for the mechanical strength measurement. For the tested blocks, the mechanical strength was measured using a universal testing machine, and the microstructure phase analysis was done by field emission scanning electron microscopy and X-ray diffraction. The cement hardening reaction occurred through the decomposition and recrystallization of MCPM and $CaSO_4{\cdot}1/2H_2O$ added on the surface of the wet prepared CaP, and this resulted in grain growth in the bone cement block.

• The Korean Journal of Ceramics
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• v.5 no.2
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• pp.162-164
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• 1999

Microsotructure designed porous ceramics of calcium hydroxyapatite $(Ca_{10}(PO_4)_6(OH)_2)$ were prepared by hydrothermal method. The particle size, shape, and the micro-pore size of the porous hydroxyapatite ceramics could becontrolled. The hydroxyapatite was non-stoichiometric apatite with calcium deficient compositions (Ca/P ratio < 1.67). The composition of non-stoichiometric hydroxyapatite ceramics could be controlled from 1.50 to 1.63 in Ca/P ratio. The hydroxyapatite ceramics preparedc at $105^{\circ}C$ under the saturated vapor pressure for 20h were composed of rod-shaped crystals with about 10$\mu\textrm{m}$ in length with the mean aspect ratio of 40. The porous ceramics of calcium deficient hydroxyapatite had about 45% porosity with the inter-connecting pore structure. Porous hydroxyapatite ceramics prepared hydrothermally had the compressive strength of about 10 to 30 MPa. In addition, porous ceramics of $\beta$-tricalcium phosphate ($\beta-Ca_3(PO_4)_2$) were prepared from the calcium deficient hydroxyapatite.

• Journal of Yeungnam Medical Science
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• v.27 no.2
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• pp.139-145
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• 2010

Cystic parathyroid adenoma is one of rare causes of hyperparathyroidism, and tends to cause increased serum level of parathyroid hormone, alkaline phosphate and serum calcium level similar to when compared to those of solid adenoma. The possibility of a coincidental appearance of primary hyperparathyrodism and nonmedullary thyroid cancer is rare, and often neglected. A 40-year-old female presented with constipation and weight loss for 3 months. The serum calcium, phosphate and alkaline phosphate were 16.6 mg/dl, 2.2 mg/dl and 505 IU/L respectively and serum parathyroid hormone level was 1556.2 pg/mL. Neck US showed mixed nodules at both thyroid lobes, and PET-CT showed a right thyroid nodule without FDG uptake. The patient was diagnosed of primary hyperparathyroidism and underwent parathyroidectomy and a total thyroidectomy. Histopathologic results revealed parathyroid adenoma with cystic change (2 cm greater diameter) in the right lower parathyroid gland and coexistent papillary carcinoma of the right lobe of thyroid gland (infiltrating, 0.3 cm in greater diameter). She remained well and serum calcium, phosphate, parathyroid hormone level were normalized within 24 hours.