Papers by Keyword: Alkaline Phosphatase

Abstract: Perforations can occur during endodontic treatment, post placement and removal, and operative procedures. These defects have been treated with a variety of different materials such as resin ionomer, glass ionomer cement and intermediate restorative material. However, the osteogenic response to these substances using osteoblasts have been rarely studied. Thus, the aim of the present study is to evaluate the osteogenic response to resin ionomer (Geristore) and mineral trioxide aggregate (MTA). The surface roughness was significantly higher in the MTA than in the resin ionomer (p<0.05). After 72 hours of incubation mouse osteoblasts attached and spread well over the surfaces of resin ionomer and MTA. As a result from MTT assay, the number of cells gradually increased as the cell incubation time increased. In particular, control group showed higher cell proliferation than the other two groups on days 3 and 5. Resin ionomer showed more active early cell proliferation than MTA (p<0.05). The alkaline phosphatase (ALP) activity was significantly higher in the MTA surface than in the resin ionomer and glass coverslip (p<0.05). Resin ionomer was active in early cell proliferation and adhesion. Resin ionomer may be more suitable for cervical perforation or for perforation of adjacent to the gingiva requiring rapid wound closure. Also, MTA has a rough surface and low initial cell adhesion but because of its superior osteogenic response, it may be appropriate for the area close to the apical region, where the perforation site is wide and the bone tissue regeneration is necessary.

Abstract: This is preliminary study in order to investigate the effect of dental pulp stem cells (DPSCs) on bone regeneration in an animal model. New Zealand rabbits were used as animal model. The critical defect was created in femoral bone and transplantation of DPSCs applied into bone defect. A colorimetric assay was used to detect ALP level in rabbit’s serum. Bone tissue regeneration was evaluated by histological analysis. In the 2nd week, the treated rabbit show increasing in the activity of ALP (157,925 μU) compared to control rabbit (155,361 μU). This increasing trend continues significantly in DPSCs rabbit (169.750 μU) compared to control rabbit (160.406) after 4 weeks. Histological evaluation revealed that the amount of bone lamellae and osteocytes were filled the defect area of DPSCs treated rabbit. Conclusions: Transplantation of DPSCs accelerating bone regeneration by raising ALP level and forming new bone tissue.

Abstract: Experiment disodium phenyl phosphate as a reaction basic, stromal hydrolysis produce phenol, the amount of phenol indirectly indicates the activity of Alkaline Phosphatase.Experiment by absorption wavelength, activated sludge volume, disodium phenyl phosphate, aluminum sulfate, reagent, temperature and other factors affecting the determination of Alkaline Phosphatase were studied.The experiments optimal reaction conditions initially identified. At 37°C, when activated sludge volume of 5mL, 15mL disodium phenyl phosphate absorbance measured at the maximum value, highest levels of Alkaline Phosphatase. Results show that, 0.25mL reagent optimum dosage for the trial, the best absorption wavelength through fitting the peak-valley is 590nm.

Abstract: Seven typical surface sediments were collected along the flow direction in the hypertrophic Qixinghu lake located in Nansi Lake Basin. The sediments were evaluated on the basis of phosphorus (P) fractionation by sequential extraction scheme. Sedimentary phosphorus were fractioned into six forms (Ex-P, Al-P, Fe-P, BD-P, Ca-P and Org-P) to reveal phosphorus removal mechanism. The rank order according to the content of P-fractions was Ca-P > Org-P > Al-P > Fe-P > Ex-P > BD-P. The permanent Ca-P showed considerable contribution (41.97%-73.15%) to the sedimentary P-loads. The relative contributions of Ex-P to total sedimentary phosphorus (TP) ranged from 0.91% to 4.64%, which was positively correlated with alkaline phosphatase activity (r=0.8480). TP and Org-P were positively correlated with organic matter (OM) (r=0.8577 and r=0.9237, respectively). Total phosphorus concentration in the sediment fluctuated with changes in water quality and substrate characteristics. The high content of sedimentary metal elements and OM are contributed to the phosphorus accumulation and adsorption.

Abstract: Sulfur dioxide (SO₂) is a ubiquitous air pollutant which causes kinds of damage to human and other organisms. However, the effects and mechanisms on the plasma membrane when cells and tissues were exposed to SO₂ were still unknown. The results herein showed a gradual reduction in body weight and dry lung weight for rats exposed to SO₂. The wet lung weights were increased. The changes indicated SO2 inhalation caused pulmonary tissue permeability edema. _{Subscript text}The pulmonary permeability was increase_{Subscript textSubscript textSubscript text}d by the determination of protein contents in BALs and pulmonary permeability index (PPI). The intracellular proteins were penetrated into extracellular matrix. The total leukocytes in BALs of rats in each group exposed to SO₂ were significantly increased, and the granulocytes were also increased significantly. However, the lymphocytes in BALs of rats exposed SO₂ were to some extent different to the control groups. The activities of acid phosphatase (ACP), alkaline phosphatase (AKP) and lactic dehydrogenase (LDH) in BALs were increased to some extent. The results showed that the functions of plasma membrane were damaged with the damage of membrane structure, parts of the membrane bound enzymes and intracellular enzymes were released into BALs. The membrane fluidity in AM cells were significantly decreased by the determination of steady-state fluorescent polarization degree (P) and fluorescence microviscosity (η) of the AM.

Abstract: Bone Tissue Engineering (BTE) composed of three main parts: scaffold, cells and signaling factors. Several materials and composites are suggested as a scaffold for BTE. Biocompatibility is one of the most important property of a BTE scaffold. In this work synthesis of a novel nanocomposite including layered double hydroxides (LDH) and gelatin is carried out and its biological properties were studied. The co-precipitation (pH=11) method was used to prepare the LDH powder, using calcium nitrate, Magesium nitrate and aluminum nitrate salts as starting materials. The resulted precipitates were dried. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analyses were used to characterize the synthesized powders. The results demonstrated the presence of nanocrystals of Ca-LDH and Mg-LDH as Hexagonal and Layered Morphology. The obtained powders were composed to gelatin via solvent casting method then freez dried. The scaffold was prepared via membrane lamination method from the resulted layers that linked together with gelatin as binder. In order to investigate the scaffold cytotoxicity MTT assay was done with a osteosarcoma cell line. No toxic response was observed in specimens. As a major result, it was demonstrated that the specimen showed a significant cellular response. Then osteosarcoma cells were cultured for 7-day and 14-day extract of powders. The composites osteoconductivity was investigate with cells alkaline phosphatase extraction. The results demonstrated that the Ca-LDH/gelatin composite scaffold has a good potential for bone tissue engineering applications and Mg-LDH specimen has a better osteconductivity.

Abstract: The inhibition kinetic parameters of pentachlorophenol (PCP) on bovine intestinal mucosa alkaline phosphatase (ALP) activity were studied by spectrophotometry. The results showed that PCP inhibited ALP activity in a concentration dependent manner, and the 50% inhibitory concentration (IC50) was estimated to be 4.20 mM. The apparent Michaelis–Menten constant (Km) and apparent maximum reaction rate (Vmax) was found to be decreased in the presence of PCP. Lineweaver–Burk plots indicated that the nature of the inhibition was of an uncompetitive type. Kinetic analysis indicated that the value of the inhibition constant (Ki) was 5.67 mM.

Abstract: Nature is full of many interesting things to work with, but many natural resources are also protected. In this view the recycling of aquaculture and fishery residues may lead to the manufacture of new devices and the isolation of new molecules with potential application in medicine. The aim of the present study was to explore the possibility to transform the cuttlefish bone into an hydroxyapatite scaffold suitable for bone tissue engineering application. The mixture of different lamellar porous structure of cuttlefish bone from the species Sepia Officinalis was selected and characterized, according to morphology (including porosity, surface development, surface characteristics) and mechanical properties. The material was transformed into suitable scaffold for bone tissue regeneration, trying to totally or partially convert calcium carbonate (aragonite) into calcium phosphate (hydroxyapatite HA) using hydrothermal transformation. The studies on cell attachment and proliferation (by MTT assay at different experimental times), cell morphology with Scanning Electron Microscopy (SEM), alkaline phosphatase (ALP) and osteocalcin (OC) activities and expressions by mouse osteoblast-like MC3T3-E1 cells on HA were investigated at different experimental times in cultures, in comparison with those observed on titanium specimens used as a control (ET and ST). Cell proliferation was less in HA transformed cuttlefish bone scaffolds than in ET and ST specimens. In contrast, good performance for osteoblasts differentiation was observed on HA transformed cuttlefish bone scaffolds, similar to those observed onto titanium scaffolds.

Abstract: This investigation is based on the premise that heavy metals are sequestered by the mineral phase of teeth [1,2], hydroxyapatite, during their formation and there is a relation between heavy metal pollution and progressive destruction of human primary tooth. Our study was carried out on temporary molars – sound and carious - extracted from children up to 6 year old, residing in an area of Romania known to be highly polluted with heavy metals (Pb and Cd). In carious dentin extracts we found increased levels of collagen type 1 and alkaline phosphatase activity that can be correlated with the remineralization processus during teeth decay. Gelatin zymography shown increased MMP-1 (type-I collagenase) and MMP-2 (gelatinase-A) activities only in dentin extract from carious teeth isolated from children residing in a highly polluted area, suggesting their role in pathological extracellular matrix (ECM) remodeling and degradation processes in the progression of carious decay.

Abstract: The Tissue Engineering appears with a modern proposal for the treatment of damages or diseases. The study of materials and methods for tissues and organs regeneration by the patient cells culture had been developed on the last years but still couldn’t be used for all different tissues. In this multidisciplinary research field, the present work joins the biodegradability of poly(ε-caprolactone) (PCL) with the osteoconductive properties of β-tricalcium phosphate (β-TCP) in order to create a composite which acts as a temporary support for cell culture without a second surgery to remove the biomaterial. This work evaluates three membranes types, obtained by casting in chloroform, on the biocompatibility and differentiation on mesenquimal stem cells (hMSC). These analyses showed cell viability with the rezasurin method and the alkaline phosphatase activity (ALP). DMA analyses, MEV and OPM were performed.