Displaying publications 201 - 220 of 294 in total

Abstract:
Sort:
  1. Mohamed Abdelrasoul, Jahangir Bin Kamaldin, Jer Ping Ooi, Ahmed Abd El-Fattah, Gihan Kotry, Omneya Ramadan, et al.
    MyJurnal
    Introduction: Melatonin (MEL) loaded alginate-chitosan/beta-tricalcium phosphate (Alg-CH/β-TCP) composite hy- drogel has been formulated as a scaffold for bone regeneration. MEL in the scaffold was anticipated to accelerate bone regeneration. The objective of this study is to observe signs of systemic toxicity and physical changes on surface defected bone for bone regenerative performance of the composite. Methods: The proximal-medial metaphyseal cortex of the left tibia of New Zealand white rabbit was the surgical site of the defect. A total of nine rabbits were randomly allocated to three groups; Group I; implanted with MEL loaded Alg-CH/β-TCP, Group II; Alg-CH/β-TCP and Group III defects were sham control. The rabbits were daily observed to determine systemic toxicity effects by composites. The physical changes to implanted site were observed using digital x-ray radiography and computerized tomography at weeks 0, 2, 4, 6 and 8 of post-implantation. Results: There were no clinical signs of systemic toxicity for all groups of rabbits. Digital radiography did not show adverse effects to the bone. Computerized tomography showed reduction in the area size and depth volume of the implantation site, but accelerated regeneration within the 8 weeks was not significantly different (P
    Matched MeSH terms: Calcium Phosphates
  2. Nur Syamimi Zainudin, Nur Aqilah Abdul Rahman
    MyJurnal
    Dyes are aromatic organic compound which have an affinity towards the substrate to which they are being applied to. The presence of dyes in wastewater samples is not safe for human even at low level. The presence of dyes in wastewater which are discharged from textile industry must be analysed. Hence, a precise, fast, accurate, simple and inexpensive analytical method with low detection limit is needed for the determination of dyes in wastewaters. The differential pulse anodic stripping voltammetric (DPASV) technique using bare glassy carbon electrode (GCE) as a working electrode and phosphate buffer at pH 4.2 as a supporting electrolyte has been proposed for Reactive Black 5 (RB5) determination. Several experimental voltammetric parameters were being optimized for obtaining a maximum response before analytical validation of the proposed technique being carried out. The optimum parameters were initial potential (Ei) = +0.3 V, end potential (Ef) = +1.0 V, scan rate (v) = 0.04 V/s, accumulation time (tacc) = 50 s, accumulation potential (Eacc) = 0.4 V and pulse amplitude = 0.075 V. The well-defined anodic peak appeared at 0.77972 V. The response was linear from 0.5 to 1.25 mg/L (R2=0.9986) with LOD of 0.050 mg/L. The relative standard deviation (RSD) achieved were 0.08 %, 0.62 % and 0.50 %, respectively for three consecutive days. The % recovery range achieved was from 89.71 % to 111.15 %. It can be concluded that the proposed technique is precise, accurate, inexpensive, fast and has a potential to be an alternative analytical technique for RB5 analysis. The proposed method will in the future be tested for the amount of RB5 in the wastewater samples from textile industry.
    Matched MeSH terms: Phosphates
  3. Shaari AL, Surif M, Latiff FA, Omar WM, Ahmad MN
    Trop Life Sci Res, 2011 May;22(1):51-69.
    PMID: 24575209
    Many reports have revealed that the abundance of microalgae in shrimp ponds vary with changes in environmental factors such as light, temperature, pH, salinity and nutrient level throughout a shrimp culture period. In this study, shrimp cultivation period was divided into three stages (initial = week 0-5, mid = week 6-10 and final = week 11-15). Physical and chemical parameters throughout the cultivation period were studied and species composition of microalgae was monitored. Physical parameters were found to fluctuate widely with light intensity ranging between 182.23-1278 μmol photon m(-2)s(-1), temperature between 29.56°C -31.59°C, dissolved oxygen (DO) between 4.56-8.21 mg/l, pH between 7.65-8.49 and salinity between 20‰-30‰. Ammonium (NH4 (+)-N), nitrite (NO2 (-)-N), nitrate (NO3 (-)-N), and orthophosphate (PO4 (3-)-P) concentrations in the pond at all cultivation stages ranged from 0.017 to 0.38 mg/l, 0.24 to 2.12 mg/l, 0.06 to 0.98 mg/l and 0.16 to 1.93 mg/l respectively. Statistical test (ANOVA) showed that there were no significant difference (p<0.05) in nutrients concentrations among the cultivation stages. All nutrients concentrations however were still in the tolerable level and safe for shrimp culture. The chlorophyll a contents were found to range from 5.03±2.17 to 32.61±0.35 μg/l throughout the cultivation period. A total of 19 microalgae species were found in the shrimp pond, with diatoms contributing up to 72% of the species followed by Chlorophyta (11%) and Cyanophyta (11%). However, weekly species abundance varied through the study period. At the initial stage, when there were no shrimps in the pond, Anabaena spp. and Oscillatoria spp. (Cyanophyta) were the dominant species, followed by Chlorella sp. and Dunaliella sp. (Chlorophyta). When shrimps were introduced into the pond, Amphora sp., Navicula sp. Gyrosigma sp. and Nitzschia sp. (diatoms) started to exist. At the middle and towards the final stage of the shrimp culture period diatoms were the dominant species. The Chlorophyta (Chlorella sp.) domination took place only twice, which was at week 2 and 13. The absence of some of the coastal water microalgae species in the shrimp pond was most likely due to the fact that they could not tolerate the physicochemical factors of harsh environment. In this study, Cylindrotheca closterium was regarded as the most tolerant species among the microalgae due to its ability to exist for 6 weeks out of the 15 weeks of cultivation.
    Matched MeSH terms: Phosphates
  4. Jaafar J, Irwan Z, Ahamad R, Terabe S, Ikegami T, Tanaka N
    J Sep Sci, 2007 Feb;30(3):391-8.
    PMID: 17396598
    An online preconcentration technique by dynamic pH junction was studied to improve the detection limit for anionic arsenic compounds by CE. The main target compound is roxarsone, or 3-nitro-4-hydroxyphenylarsonic acid, which is being used as an animal feed additive. The other inorganic and organoarsenic compounds studied are the possible biotransformation products of roxarsone. The arsenic species were separated by a dynamic pH junction in a fused-silica capillary using 15 mM phosphate buffer (pH 10.6) as the BGE and 15 mM acetic acid as the sample matrix. CE with UV detection was monitored at a wavelength of 192 nm. The influence of buffer pH and concentration on dynamic pH junction were investigated. The arsenic species focusing resulted in LOD improvement by a factor of 100-800. The combined use of C18 and anion exchange SPE and dynamic pH junction to CE analysis of chicken litter and soils helps to increase the detection sensitivity. Recoveries of spiked samples ranged between 70 and 72%.
    Matched MeSH terms: Phosphates
  5. Alotaibi AM, Ismail AF, Aziman ES
    Sci Rep, 2023 Jun 08;13(1):9316.
    PMID: 37291241 DOI: 10.1038/s41598-023-36487-5
    This study investigated the efficacy of using phosphate-modified zeolite (PZ) as an adsorbent for removing thorium from aqueous solutions. The effects of various factors such as contact time, adsorbent mass, initial thorium concentration, and pH value of the solution on the removal efficiency were analyzed using the batch technique to obtain optimum adsorption condition. The results revealed that the optimal conditions for thorium adsorption were a contact time of 24 h, 0.03 g of PZ adsorbent, pH 3, and a temperature of 25 °C. Isotherm and kinetics parameters of the thorium adsorption on PZ were also determined, with equilibrium studies showing that the experimental data followed the Langmuir isotherm model. The maximum adsorption capacity (Qo) for thorium was found to be 17.3 mg/g with the Langmuir isotherm coefficient of 0.09 L/mg. Using phosphate anions to modify natural zeolite increased its adsorption capacity. Furthermore, adsorption kinetics studies demonstrated that the adsorption of thorium onto PZ adsorbent fitted well with the pseudo-second-order model. The applicability of the PZ adsorbent in removing thorium from real radioactive waste was also investigated, and nearly complete thorium removal was achieved (> 99%) from the leached solution obtained from cracking and leaching processes of rare earth industrial residue under optimized conditions. This study elucidates the potential of PZ adsorbent for efficient removal of thorium from rare earth residue via adsorption, leading to a reduction in waste volume for ultimate disposition.
    Matched MeSH terms: Phosphates
  6. Fatema K, Wan Maznah WO, Isa MM
    Trop Life Sci Res, 2014 Dec;25(2):1-19.
    PMID: 27073596 MyJurnal
    In this study, factor analysis (FA) was applied to extract the hidden factors responsible for water quality variations during both wet and dry seasons. Water samples were collected from six sampling stations (St. 1 Lalang River, St. 2 Semeling River, St. 3 Jagung River, St. 4 Teluk Wang River, St. 5 Gelam River and St. 6 Derhaka River) in the Merbok estuary, Malaysia from January to December 2011; the samples were further analysed in the laboratory. Correlation analysis of the data sets showed strong correlations between the parameters. Nutrients such as nitrate (NO3 (-)), nitrite (NO2 (-)), ammonia (NH3) and phosphate (PO4 (3-)) were determined to be critical indicators of water quality throughout the year. Influential water quality parameters during the wet season were conductivity, salinity, biochemical oxygen demand (BOD), dissolved oxygen (DO) and chlorophyll a (Chla), whereas total suspended solid (TSS) and pH were critical water quality indicators during the dry season. The Kruskal-Wallis H test showed that water quality parameters were significantly different among the sampling months and stations (p<0.05), and Mann-Whitney U tests further revealed that the significantly different parameters were temperature, pH, DO, TSS, NO2 (-) and BOD (p<0.01), whereas salinity, conductivity, NO3 (-), PO4 (3-), NH3 and Chla were not significantly different (p>0.05). Water quality parameters in the estuary varied on both temporal and spatial scales and these results may serve as baseline information for estuary management, specifically for the Merbok estuary.
    Matched MeSH terms: Phosphates
  7. Minhat FI, Yahya K, Talib A, Ahmad O
    Trop Life Sci Res, 2013 Aug;24(1):35-43.
    PMID: 24575240 MyJurnal
    The distribution of benthic Foraminifera throughout the coastal waters of Taman Negara Pulau Pinang (Penang National Park), Malaysia was studied to assess the impact of various anthropogenic activities, such as fishing, ecotourism and floating cage culture. Samples were obtained at 200 m intervals within the subtidal zone, extending up to 1200 m offshore at Teluk Bahang, Teluk Aling, Teluk Ketapang and Pantai Acheh. The depth within coastal waters ranged between 1.5 m and 10.0 m, with predominantly muddy substrate at most stations. Water quality analysis showed little variation in micronutrient (nitrite, NO2; nitrate, NO3; ammonia, NH4 and orthophosphate, PO4) concentrations between sampling stations. Temperature (29.6±0.48°C), salinity (29.4±0.28 ppt), dissolved oxygen content (5.4±0.95 mg/l) and pH (8.5± 0.13) also showed little fluctuation between stations. A total of nine genera of foraminifera were identified in the study (i.e., Ammonia, Elphidium, Ammobaculites, Bigenerina, Quinqueloculina, Reopax, Globigerina, Textularia and Nonion). The distribution of benthic foraminifera was dominated by opportunistic groups that have a high tolerance to anthropogenic stressors. Ammonia had the highest frequency of occurrence (84.7%), followed by Bigenerina (50%), Ammobaculites (44.2%) and Elphidium (38.9%). The Ammonia-Elphidium Index (AEI) was used to describe the hypoxic condition of benthic communities at all sites. Teluk Bahang had the highest AEI value. The foraminiferal assemblages and distribution in Teluk Bahang, Teluk Aling, Teluk Ketapang and Pantai Acheh showed no correlation with physical or chemical environmental parameters.
    Matched MeSH terms: Phosphates
  8. Atif M, Khalid SH, Onn Kit GL, Sulaiman SA, Asif M, Chandersekaran A
    J Young Pharm, 2013 Mar;5(1):26-9.
    PMID: 24023449 DOI: 10.1016/j.jyp.2013.01.005
    A simple, sensitive and selective HPLC method with UV detection for determination of Glipizide in human plasma was developed. Liquid-liquid extraction method was used to extract the drug from the plasma samples. Chromatographic separation of Glipizide was achieved using C18 column (ZORBAX ODS 4.6 × 150 mm). The mobile phase was comprised of 0.01 M potassium dihydrogen phosphate and acetonitrile (65:35, v/v) adjusted to pH 4.25 with glacial acetic acid. The analysis was run at a flow rate of 1.5 mL/min with an injection volume was 20 μL. The detector was operated at 275 nm. The calibration curve was linear over a concentration range of 50-1600 ng/mL. Intra-day and inter-day precision and accuracy values were below 15%. The limit of quantification was 50 ng/mL and the mean recovery was above 98%. Freeze-thaw, short-term, long-term and post-preparative stability studies showed that Glipizide in plasma sample was stable. The method may be successfully applied to analyze the Glipizide concentration in plasma samples for bioavailability and bioequivalence studies.
    Matched MeSH terms: Phosphates
  9. Dailin DJ, Elsayed EA, Othman NZ, Malek R, Phin HS, Aziz R, et al.
    Saudi J Biol Sci, 2016 Jul;23(4):495-502.
    PMID: 27298582 DOI: 10.1016/j.sjbs.2015.06.003
    Lactobacillus kefiranofaciens is non-pathogenic gram positive bacteria isolated from kefir grains and able to produce extracellular exopolysaccharides named kefiran. This polysaccharide contains approximately equal amounts of glucose and galactose. Kefiran has wide applications in pharmaceutical industries. Therefore, an approach has been extensively studied to increase kefiran production for pharmaceutical application in industrial scale. The present work aims to maximize kefiran production through the optimization of medium composition and production in semi industrial scale bioreactor. The composition of the optimal medium for kefiran production contained sucrose, yeast extract and K2HPO4 at 20.0, 6.0, 0.25 g L(-1), respectively. The optimized medium significantly increased both cell growth and kefiran production by about 170.56% and 58.02%, respectively, in comparison with the unoptimized medium. Furthermore, the kinetics of cell growth and kefiran production in batch culture of L. kefiranofaciens was investigated under un-controlled pH conditions in 16-L scale bioreactor. The maximal cell mass in bioreactor culture reached 2.76 g L(-1) concomitant with kefiran production of 1.91 g L(-1).
    Matched MeSH terms: Phosphates
  10. Wang Y, Molin DG, Sevrin C, Grandfils C, van den Akker NM, Gagliardi M, et al.
    Int J Pharm, 2016 Apr 30;503(1-2):150-62.
    PMID: 26965198 DOI: 10.1016/j.ijpharm.2016.03.002
    Poly(d,l-lactic acid) biodegradable microspheres, loaded with the drugs cisplatin and/or sorafenib tosylate, were prepared, characterized and studied. Degradation of the microspheres, and release of cisplatin and/or sorafenib tosylate from them, were investigated in detail. Incubation of the drug-carrying microspheres in phosphate buffered saline (pH=7.4) revealed slow degradation. Nevertheless, significant release of cisplatin and sorafenib tosylate from microspheres loaded with both drugs was apparent in vitro; this can be attributed to their porous structure. Supernatants from microspheres loaded with both drugs showed strong toxic effects on cells (i.e. endothelial cells, fibroblast cells and Renca tumor cells) and potent anti-angiogenic effect in the matrigel endothelial tube assay. In vivo anti-tumor effects of the microspheres were also observed, in a Renca tumor mouse model. The poly(d,l-lactic acid) microspheres containing both cisplatin and sorafenib tosylate revealed highest therapeutic efficacy, probably demonstrating that combined local administration of cisplatin and sorafenib tosylate synergistically inhibits tumor growth in situ. In conclusion, this study demonstrates the applicability of biodegradable poly(d,l-lactic acid) microspheres loaded with cisplatin and sorafenib tosylate for local drug delivery as well as the potential of these microspheres for future use in transarterial chemoembolization.
    Matched MeSH terms: Phosphates
  11. Ibrahim S, Sabudin S, Sahid S, Marzuke MA, Hussin ZH, Kader Bashah NS, et al.
    Saudi J Biol Sci, 2016 Jan;23(1):S56-63.
    PMID: 26858566 DOI: 10.1016/j.sjbs.2015.10.024
    Surface reactivity of bioactive ceramics contributes in accelerating bone healing by anchoring osteoblast cells and the connection of the surrounding bone tissues. The presence of silicon (Si) in many biocompatible and bioactive materials has been shown to improve osteoblast cell adhesion, proliferation and bone regeneration due to its role in the mineralisation process around implants. In this study, the effects of Si-biphasic calcium phosphate (Si-BCP) on bioactivity and adhesion of human osteoblast (hFOB) as an in vitro model have been investigated. Si-BCP was synthesised using calcium hydroxide (Ca(OH)2) and phosphoric acid (H3PO4) via wet synthesis technique at Ca/P ratio 1.60 of material precursors. SiO2 at 3 wt% based on total precursors was added into apatite slurry before proceeding with the spray drying process. Apatite powder derived from the spray drying process was pressed into discs with Ø 10 mm. Finally, the discs were sintered at atmospheric condition to obtain biphasic hydroxyapatite (HA) and tricalcium phosphate (TCP) peaks simultaneously and examined by XRD, AFM and SEM for its bioactivity evaluation. In vitro cell viability of L929 fibroblast and adhesion of hFOB cell were investigated via AlamarBlue® (AB) assay and SEM respectively. All results were compared with BCP without Si substitution. Results showed that the presence of Si affected the material's surface and morphology, cell proliferation and cell adhesion. AFM and SEM of Si-BCP revealed a rougher surface compared to BCP. Bioactivity in simulated body fluid (SBF) was characterised by pH, weight gain and apatite mineralisation on the sample surface whereby the changes in surface morphology were evaluated using SEM. Immersion in SBF up to 21 days indicated significant changes in pH, weight gain and apatite formation. Cell viability has demonstrated no cytotoxic effect and denoted that Si-BCP promoted good initial cell adhesion and proliferation. These results suggest that Si-BCP's surface roughness (164 nm) was significantly higher than BCP (88 nm), thus enhancing the adhesion and proliferation of the osteoblast.
    Matched MeSH terms: Calcium Phosphates
  12. Cui M, Jang M, Kang K, Kim D, Snyder SA, Khim J
    Chemosphere, 2016 Feb;144:2081-90.
    PMID: 26583290 DOI: 10.1016/j.chemosphere.2015.10.107
    A novel and economic sequential process consisting of precipitation, adsorption, and oxidation was developed to remediate actual rare-earth (RE) wastewater containing various toxic pollutants, including radioactive species. In the precipitation step, porous air stones (PAS) containing waste oyster shell (WOS), PASWOS, was prepared and used to precipitate most heavy metals with >97% removal efficiencies. The SEM-EDS analysis revealed that PAS plays a key role in preventing the surface coating of precipitants on the surface of WOS and in releasing the dissolved species of WOS successively. For the adsorption step, a polyurethane (PU) impregnated by coal mine drainage sludge (CMDS), PUCMDS, was synthesized and applied to deplete fluoride (F), arsenic (As), uranium (U), and thorium (Th) that remained after precipitation. The continuous-mode sequential process using PAS(WOS), PU(CMDS), and ozone (O3) had 99.9-100% removal efficiencies of heavy metals, 99.3-99.9% of F and As, 95.8-99.4% of U and Th, and 92.4% of COD(Cr) for 100 days. The sequential process can treat RE wastewater economically and effectively without stirred-tank reactors, pH controller, continuous injection of chemicals, and significant sludge generation, as well as the quality of the outlet met the EPA recommended limits.
    Matched MeSH terms: Phosphates
  13. Shima WN, Ali AM, Subramani T, Mohamed Alitheen NB, Hamid M, Samsudin AR, et al.
    Exp Ther Med, 2015 Jun;9(6):2202-2206.
    PMID: 26136960
    Mesenchymal stem cells (MSCs) are involved in bone formation in the embryo, bone repair and remodeling. The differentiation of these cells is a complex multistep pathway that involves discrete cellular transitions and is similar to that which occurs during hematopoiesis. MSCs have self-renewal capacity without differentiation in long-term culture. In the present study, MSCs were isolated from human bone marrow and characterized by the presence of cluster of differentiation 105 marker using the labeled streptavidin biotin method. The MSCs were cultured in Dulbecco's modified Eagle's medium supplemented with fetal bovine serum, ascorbic acid, β-glycerol phosphate and dexamethasone to differentiate into osteoblasts. Biological in vitro analysis showed the rapid proliferation of the MSCs. Further evaluation of specific osteogenic markers using von Kossa staining and the alkaline phosphate assay demonstrated that the MSCs were stimulated to differentiate into osteoblast-lineage cells. This mesengenic potential indicated that the bone marrow-derived cells were multipotent MSCs. The findings of this study show that bone marrow can be a legitimate source of MSCs for the production of osteoblasts for utilization in bone replacement therapy.
    Matched MeSH terms: Glycerophosphates; Phosphates
  14. Alotaibi AM, Ismail AF
    Int J Environ Res Public Health, 2022 Oct 23;19(21).
    PMID: 36360653 DOI: 10.3390/ijerph192113774
    The natural zeolite has been modified with sulphate and phosphate. The adsorption of thorium from the aqueous solutions by using the natural and modified zeolites has been investigated via a batch method. The adsorbent samples were characterized by X-ray Diffraction (XRD), N2 adsorption-desorption (BET), Fourier transform infrared (FTIR), field emission scanning electron microscopy (FESEM), and energy dispersive X-ray spectroscopy (EDX). Modification of natural zeolite with sulphate and phosphate was found to increase its adsorption capacity of thorium but reduced its specific surface area (SBET). The adsorption experiments were expressed by Langmuir, Freundlich and Dubinin-Radushkevitch (D-R) isotherm models and the results of adsorption demonstrated that the adsorption of thorium onto the natural and modified zeolites correlated better with the Langmuir isotherm model than with the Freundlich isotherm model. The maximum adsorption capacity (Qo) was determined using the Langmuir isotherm model at 25 °C and was found to be 17.27, 13.83, and 10.21 mg/g for phosphate-modified zeolite, sulfate-modified zeolite, and natural zeolite, respectively. The findings of this study indicate that phosphate-modified zeolite can be utilized as an effective and low-cost adsorbent material for the removal of thorium from aqueous solutions.
    Matched MeSH terms: Phosphates
  15. Imron MF, Hestianingsi WOA, Putranto TWC, Citrasari N, Abdullah SRS, Hasan HA, et al.
    Chemosphere, 2024 Apr;353:141595.
    PMID: 38438021 DOI: 10.1016/j.chemosphere.2024.141595
    Increasing aquaculture cultivation produces large quantities of wastewater. If not handled properly, it can have negative impacts on the environment. Constructed wetlands (CWs) are one of the phytoremediation methods that can be applied to treat aquaculture effluent. This research was aimed at determining the performance of Cyperus rotundus in removing COD, BOD, TSS, turbidity, ammonia, nitrate, nitrite, and phosphate from the batch CW system. Treatment was carried out for 30 days with variations in the number of plants (10, 15, and 20) and variations in media height (10, 12, and 14 cm). The result showed that aquaculture effluent contains high levels of organic compounds and nutrients, and C. rotundus can grow and thrive in 100% of aquaculture effluent. Besides that, the use of C. rotundus in CWs with the effect of numbers of plants and media height showed performance of COD, BOD, TSS, turbidity, ammonia, nitrate, nitrite, and phosphate with 70, 79, 90, 96, 64, 82, 92, and 48% of removal efficacy, respectively. There was no negative impact observed on C. rotundus growth after exposure to aquaculture effluent, as indicated by the increase in wet weight, dry weight, and growth rate when compared to the control. Thus, adding aquaculture effluent to CWs planted with C. rotundus supports the growth and development of plants while also performing phytoremediation.
    Matched MeSH terms: Phosphates
  16. Al-Gheethi AA, Mohamed RM, Jais NM, Efaq AN, Abd Halid A, Wurochekke AA, et al.
    J Water Health, 2017 Oct;15(5):741-756.
    PMID: 29040077 DOI: 10.2166/wh.2017.080
    The present study aims to investigate the influence of Staphylococcus aureus, Escherichia coli and Enterococcus faecalis in public market wastewater on the removal of nutrients in terms of ammonium (NH4-) and orthophosphate (PO43) using Scenedesmus sp. The removal rates of NH4- and orthophosphate PO43- and batch kinetic coefficient of Scenedesmus sp. were investigated. The phycoremediation process was carried out at ambient temperature for 6 days. The results revealed that the pathogenic bacteria exhibited survival potential in the presence of microalgae but they were reduced by 3-4 log at the end of the treatment process. The specific removal rates of NH4- and PO43- have a strong relationship with initial concentration in the public market wastewater (R2 = 0.86 and 0.80, respectively). The kinetic coefficient of NH4- removal by Scenedesmus sp. was determined as k = 4.28 mg NH4- 1 log10 cell mL-1 d-1 and km = 52.01 mg L-1 (R2 = 0.94) while the coefficient of PO43- removal was noted as k = 1.09 mg NH4- 1 log10 cell mL-1 d-1 and km = 85.56 mg L-1 (R2 = 0.92). It can be concluded that Scenedesmus sp. has high competition from indigenous bacteria in the public market wastewater to remove nutrients, with a higher coefficient of removal of NH4- than PO43.
    Matched MeSH terms: Phosphates/metabolism*
  17. Majithia U, Venkataraghavan K, Choudhary P, Trivedi K, Shah S, Virda M
    Indian J Dent Res, 2016 Sep-Oct;27(5):521-527.
    PMID: 27966511 DOI: 10.4103/0970-9290.195642
    INTRODUCTION: In an attempt to manage noncavitated carious lesions noninvasively through remineralization, a range of novel fluoride varnishes with additional remineralizing agents have been made available for clinical application.

    AIM AND OBJECTIVES: The aim of this study was to compare and evaluate the remineralization potential of three commercially available varnishes on artificial enamel lesions.

    MATERIALS AND METHODS: This in vitro study involves eighty intact enamel specimens prepared from premolars extracted for orthodontic purposes. After specimen preparation, the eighty samples were divided randomly into two groups (n = 40) for measurement of baseline surface Vickers microhardness and baseline calcium/phosphorus ratio (% weight) through EDAX testing. Thereafter, the specimens were subjected to demineralization for 96 h to induce initial enamel lesions and the measurements were repeated. Following demineralization, each of the two groups was divided randomly into four subgroups (n = 10) from which one was used as the control group and the others three were allotted to each of the three test varnishes. After varnish application, all the specimens were subjected to a pH cycling regimen that included alternative demineralization (3 h) and remineralization (21 h) daily, for 5 consecutive days. The Vickers microhardness and EDAX measurements were then repeated.

    RESULTS: One-way ANOVA and post hoc Tukey's tests were conducted for multiple group comparison. All the three commercially available varnishes were capable of remineralizing initial enamel lesions that were induced artificially. No difference was noted in the remineralizing efficacy of the varnishes despite their different compositions. MI Varnish™ (casein phosphopeptide-amorphous calcium phosphate fluoride varnish) showed slightly better recovery in surface microhardness as compared to the other two varnishes.

    CONCLUSION: All the varnishes used in this in vitro study are capable of reversing early enamel lesions.
    Matched MeSH terms: Calcium Phosphates/pharmacology
  18. Md Ralib A, Mat Nor MB
    Asia Pac J Clin Nutr, 2018 2 1;27(2):329-335.
    PMID: 29384319 DOI: 10.6133/apjcn.062017.09
    BACKGROUND AND OBJECTIVES: Refeeding hypophosphataemia (RH) is characterized by an acute electrolyte derangement following nutrition therapy. Complications associated include heart failure, respiratory failure, paraesthesia, seizure and death. We aim to assess its incidence, risk factors, and outcome in our local intensive care unit (ICU).

    METHODS AND STUDY DESIGN: A prospective observational cohort study was conducted at the mixed medical- surgical of a tertiary ICU in Kuantan, Malaysia. The study was registered under the National Medical Research Register (NMRR-14-803-19813) and has received ethical approval. Inclusion criteria include adult admission longer than 48 hours who were started on enteral feeding. Chronic renal failure patients and those receiving dialysis were excluded. RH was defined as plasma phosphate less than 0.65 mmol/L and a drop of more than 0.16 mmol/L following feeding.

    RESULTS: A total of 109 patients were recruited, of which 44 (42.6%) had RH. Patients with RH had higher SOFA score compared to those without (p=0.04). There were no differences in the APACHE II and NUTRIC scores. Serum albumin was lower in those with RH (p=0.04). After refeeding, patients with RH had lower serum phosphate, magnesium and albumin, and higher supplementation of phosphate, potassium and calcium. There were no differences in mortality, length of hospital or ICU stay.

    CONCLUSIONS: Refeeding hypophosphataemia occurs in almost half of ICU admission. Risk factors for refeeding include high organ failure score and low albumin. Refeeding was associated with imbalances in phosphate, magnesium, potassium and calcium. Future larger study may further investigate these risk factors and long-term outcomes.

    Matched MeSH terms: Phosphates/blood*
  19. Lioufas N, Toussaint ND, Pedagogos E, Elder G, Badve SV, Pascoe E, et al.
    BMJ Open, 2019 Feb 21;9(2):e024382.
    PMID: 30796122 DOI: 10.1136/bmjopen-2018-024382
    INTRODUCTION: Patients with chronic kidney disease (CKD) are at heightened cardiovascular risk, which has been associated with abnormalities of bone and mineral metabolism. A deeper understanding of these abnormalities should facilitate improved treatment strategies and patient-level outcomes, but at present there are few large, randomised controlled clinical trials to guide management. Positive associations between serum phosphate and fibroblast growth factor 23 (FGF-23) and cardiovascular morbidity and mortality in both the general and CKD populations have resulted in clinical guidelines suggesting that serum phosphate be targeted towards the normal range, although few randomised and placebo-controlled studies have addressed clinical outcomes using interventions to improve phosphate control. Early preventive measures to reduce the development and progression of vascular calcification, left ventricular hypertrophy and arterial stiffness are crucial in patients with CKD.

    METHODS AND ANALYSIS: We outline the rationale and protocol for an international, multicentre, randomised parallel-group trial assessing the impact of the non-calcium-based phosphate binder, lanthanum carbonate, compared with placebo on surrogate markers of cardiovascular disease in a predialysis CKD population-the IM pact of P hosphate R eduction O n V ascular E nd-points (IMPROVE)-CKD study. The primary objective of the IMPROVE-CKD study is to determine if the use of lanthanum carbonate reduces the burden of cardiovascular disease in patients with CKD stages 3b and 4 when compared with placebo. The primary end-point of the study is change in arterial compliance measured by pulse wave velocity over a 96-week period. Secondary outcomes include change in aortic calcification and biochemical parameters of serum phosphate, parathyroid hormone and FGF-23 levels.

    ETHICS AND DISSEMINATION: Ethical approval for the IMPROVE-CKD trial was obtained by each local Institutional Ethics Committee for all 17 participating sites in Australia, New Zealand and Malaysia prior to study commencement. Results of this clinical trial will be published in peer-reviewed journals and presented at conferences.

    TRIAL REGISTRATION NUMBER: ACTRN12610000650099.

    Matched MeSH terms: Phosphates/blood*
  20. Hapidin H, Romli NAA, Abdullah H
    Microsc Res Tech, 2019 Nov;82(11):1928-1940.
    PMID: 31423711 DOI: 10.1002/jemt.23361
    Tannic acid (TA) is a phenolic compound that might act directly on osteoblast metabolism. The study was performed to investigate the effects of TA on the proliferation, mineralization, and morphology of human fetal osteoblast cells (hFOB 1.19). The cells were divided into TA-treated, untreated, and pamidronate-treated (control drug) groups. Half maximal effective concentration (EC50 ) values for TA and pamidronate were measured using MTT assay. The EC50 of hFOB 1.19 cells treated with TA was 2.94 M. This concentration was more effective compared to the pamidronate (15.27 M). Cell proliferation assay was performed to compare cell viability from Day 1 until Day 14. The morphology of hFOB 1.19 was observed via inverted microscope and scanning electron microscope. Calcium (Ca) and phosphate (P) were assessed using energy-dispersive X-ray (EDX) analysis. Furthermore, the mineralization of hFOB 1.19 was determined by von Kossa staining (P depositions) and Alizarin Red S staining (Ca depositions). The number of cells treated with TA was significantly higher than the two control groups at Day 10 and Day 14. The morphology of cells treated with TA was uniformly fusiform-shaped with filopodia extensions. Besides, globular-like structures of deposited minerals were observed in the TA-treated group. In line with other findings, EDX spectrum analysis confirmed the presence of Ca and P. The cells treated with TA had significantly higher percentage of both minerals at Day 3 and Day 10 compared to the two control groups. In conclusion, TA enhances cell proliferation and causes cell morphology changes, as well as improved mineralization.
    Matched MeSH terms: Phosphates/analysis
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links