Displaying publications 1 - 20 of 63 in total

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  1. Hassandarvish P, Tiong V, Sazaly AB, Mohamed NA, Arumugam H, Ananthanarayanan A, et al.
    Br Dent J, 2020 06;228(12):900.
    PMID: 32591671 DOI: 10.1038/s41415-020-1794-1
    Matched MeSH terms: Povidone-Iodine*
  2. Thalluri C, Amin R, Mandhadi JR, Gacem A, Emran TB, Dey BK, et al.
    Biomed Res Int, 2022;2022:2467574.
    PMID: 36046453 DOI: 10.1155/2022/2467574
    Ondansetron tablets that are directly compressed using crospovidone and croscarmellose as a synthetic super disintegrant are the subject of this investigation. A central composite, response surface, randomly quadratic, nonblock (version 13.0.9.0) 32 factorial design is used to optimize the formulation (two-factor three-level). To make things even more complicated, nine different formulation batches (designated as F1-F9) were created. There were three levels of crospovidone and croscarmellose (+1, 0, -1). In addition to that, pre- and postcompressional parameters were evaluated, and all evaluated parameters were found to be within acceptable range. Among all postcompressional parameter dispersion and disintegration time, in vitro drug release experiments (to quantify the amount of medication released from the tablet) and their percentage prediction error were shown to have a significant influence on three dependent variables. Various pre- and postcompression characteristics of each active component were tested in vitro. Bulk density, tap density, angle of repose, Carr's index, and the Hausner ratio were all included in this analysis, as were many others. This tablet's hardness and friability were also assessed along with its dimension and weight variations. Additional stability studies may be conducted using the best batch of the product. For this study, we utilised the Design-Expert software to select the formulation F6, which had dispersion times of 17.67 ± 0.03 seconds, disintegration times of 120.12 ± 0.55 seconds, and percentage drug release measurements of 99.25 ± 0.36 within 30 minutes. Predicted values and experimental data had a strong correlation. Fast dissolving pills of ondansetron hydrochloride may be created by compressing the tablets directly.
    Matched MeSH terms: Povidone*
  3. Kyaw Oo M, Mandal UK, Chatterjee B
    Pharm Dev Technol, 2017 Feb;22(1):2-12.
    PMID: 26616399 DOI: 10.3109/10837450.2015.1116568
    High melting point polymeric carrier without plasticizer is unacceptable for solid dispersion (SD) by melting method. Combined polymer-plasticizer carrier significantly affects drug solubility and tableting property of SD.
    Matched MeSH terms: Povidone
  4. Pramana IGAN, Hariani L, Zarasade L
    Med J Malaysia, 2023 Jul;78(4):484-487.
    PMID: 37518916
    INTRODUCTION: Effective antiseptic use is essential in healthcare settings to prevent the spread of diseases, especially in areas with high patient traffic and exposure to various pathogens. One essential pathogenic germ is Acinetobacter baumannii. Octenidine and povidone-iodine have been demonstrated to be effective against A. baumannii in vitro. This study will compare octenidine dihydrochloride and povidone-iodine as wound-cleansing solutions for wounds contaminated with A. baumannii in vivo.

    MATERIALS AND METHODS: Twenty-four rats were divided into three groups: normal saline, octenidine dihydrochloride and povidone-iodine. Wounds were made on the rats' backs, and A. baumannii germs were inoculated into the wounds. After 3 hours, the wound was irrigated with wound cleansing solution according to the group for 30 seconds. Each wound was taken swab culture before and after wound irrigation and tissue culture 5 hours after wound irrigation.

    RESULTS: All specimens showed bacterial colony growth with a median value of 1.22 × 105 CFU before irrigation. Wound irrigation with normal saline did not reduce colony counts, while there was a 3-log reduction to 5-log reduction in the octenidine and povidone-iodine groups. Statistically, there was no significant difference in the mean number of colonies between the octenidine and povidone-iodine groups after irrigation (p = 0.535). However, 3 hours after irrigation, all specimens that experienced 3-log reduction showed regrowth to more than 1 × 105 CFU. In contrast, specimens subjected to 5-log reduction did not exhibit any regrowth.

    CONCLUSION: The antiseptic effectiveness of octenidine dihydrochloride is equivalent to povidone-iodine in eradicating A. baumannii colonies in wounds in vivo.

    Matched MeSH terms: Povidone-Iodine/pharmacology
  5. Gorajana A, Kit WW, Dua K
    Recent Pat Drug Deliv Formul, 2015;9(2):167-82.
    PMID: 25714525
    OBJECTIVE: Norfloxacin has a low aqueous solubility which leads to poor dissolution. Keeping this fact in mind the purpose of the present study is to formulate and evaluate norfloxacin solid dispersion.

    METHODS: Solid dispersions were prepared using hydrophilic carriers like polyethylene glycol (PEG) 4000, polyvinylpyrrolidone (PVP) k30 and carbopol 974pNF (CP) in various ratios using solvent evaporation technique. These formulations were evaluated using solubility studies, dissolution studies; Fourier transmitted infrared spectroscopy (FTIR), X-ray diffraction (XRD), and differential scanning calorimetery (DSC). The influence of polymer type and drug to polymer ratio on the solubility and dissolution rate of norfloxacin was also evaluated.

    RESULTS: FTIR analysis showed no interaction of all three polymers with norfloxacin. The results from XRD and DSC analyses of the solid dispersion preparations showed that norfloxacin existsin its amorphous form. Among the Norfloxacin: PEG solid dispersions, Norfloxacin: PEG 1:14 ratio showed the highest dissolution rate at pH 6.8. For norfloxacin: PVP solid dispersions, norfloxacin: PVP 1:10 ratio showed the highest dissolution rate at pH 6.8. For Norfloxacin: CP solid dispersions, norfloxacin: P 1:2 ratio showed the highest dissolution rate at pH 6.8.

    CONCLUSION: The solid dispersion of norfloxacin with polyethylene glycol (PEG) 4000, polyvinylpyrrolidone (PVP) k30 and carbopol 974p NF (CP), lends an ample credence for better therapeutic efficacy.

    Matched MeSH terms: Povidone/pharmacokinetics; Povidone/chemistry*
  6. Alnaqi A, Burhamah W, Al-Sultan AT, Taqi E
    World J Surg, 2023 Feb;47(2):448-454.
    PMID: 36316513 DOI: 10.1007/s00268-022-06788-3
    INTRODUCTION: Topical agents are sometimes applied to surgical wounds after closure; these may include antiseptics or antibiotics. Minimal research has been undertaken to investigate the effect of topical regimens on the tensile strength of suture materials.

    AIM: To investigate the effect of four commonly used wound care regimens on the tensile strength of suture materials.

    METHODS: The failure load of 9 different suture materials was tested using the Instron Electroplus E3000 tensile testing machine (Instron Corporation, Norwood, Massachusetts). Tensile strength was represented as the failure load, measured in Newtons (N), and defined as the maximal load that could be applied across the suture prior to failure. Each suture was tested dry and after immersion in one of 4 products for 7 days and tested on day 7. The immersion agents tested were: sodium chloride 0.9%, MicroSafe® (Sonoma Pharmaceuticals, Petaluma, CA), Aqueous Povidone-iodine 10% solution (Betadine-Mundipharma), and Fucidin ointment.

    RESULTS: Sodium chloride 0.9%, MicroSafe®, Aqueous Povidone-iodine 10%, and Fucidin seem to increase the failure load of most absorbable and non-absorbable sutures. However, the failure load of Polyglactin 910 suture (Surgilactin, coated, violet-Ethicon) is reduced by long-term exposure to either sodium chloride 0.9% or MicroSafe®, while the failure load of the Polydioxanone suture (PDS Plus-Ethicon) is reduced by long-term exposure to MicroSafe® only.

    CONCLUSION: In our experiment, the commonly used wound care products have been shown to alter the tensile strength of suture materials. Further human studies are required to ascertain the clinical validity and applicability of our findings.

    Matched MeSH terms: Povidone-Iodine*
  7. Soltani N, Saion E, Erfani M, Rezaee K, Bahmanrokh G, Drummen GP, et al.
    Int J Mol Sci, 2012;13(10):12412-27.
    PMID: 23202906 DOI: 10.3390/ijms131012412
    Zinc sulfide semiconductor nanoparticles were synthesized in an aqueous solution of polyvinyl pyrrolidone via a simple microwave irradiation method. The effect of the polymer concentration and the type of sulfur source on the particle size and dispersion of the final ZnS nanoparticle product was carefully examined. Microwave heating generally occurs by two main mechanisms: dipolar polarization of water and ionic conduction of precursors. The introduction of the polymer affects the heating rate by restriction of the rotational motion of dipole molecules and immobilization of ions. Consequently, our results show that the presence of the polymer strongly affects the nucleation and growth rates of the ZnS nanoparticles and therefore determines the average particle size and the dispersion. Moreover, we found that PVP adsorbed on the surface of the ZnS nanoparticles by interaction of the C-N and C=O with the nanoparticle's surface, thereby affording protection from agglomeration by steric hindrance. Generally, with increasing PVP concentration, mono-dispersed colloidal solutions were obtained and at the optimal PVP concentration (5%), sufficiently small size and narrow size distributions were obtained from both sodium sulfide and thioacetamide sulfur sources. Finally, the sulfur source directly influences the reaction mechanism and the final particle morphology, as well as the average size.
    Matched MeSH terms: Povidone/chemistry*
  8. Irfan M, Irfan M, Idris A, Baig N, Saleh TA, Nasiri R, et al.
    J Biomed Mater Res A, 2019 03;107(3):513-525.
    PMID: 30484939 DOI: 10.1002/jbm.a.36566
    This study focused to optimize the performance of polyethersulfone (PES) hemodialysis (HD) membrane using carboxylic functionalized multiwall carbon nanotubes (c-MWCNT) and lower molecular weight grade of polyvinylpyrrolidone (PVP-k30). Initially, MWCNT were chemically functionalized by acid treatment and nanocomposites (NCs) of PVP-k30 and c-MWCNT were formed and subsequently blended with PES polymer. The spectra of FTIR of the HD membranes revealed that NCs has strong hydrogen bonding and their addition to PES polymer improved the capillary system of membranes as confirmed by Field Emission Scanning Electron Microscope (FESEM) and leaching of the additive decreased to 2% and hydrophilicity improved to 22%. The pore size and porosity of NCs were also enhanced and rejection rate was achieved in the establish dialysis range (<60 kDa). The antifouling studies had shown that NCs membrane exhibited 30% less adhesion of protein with 80% flux recovery ratio. The blood compatibility assessment disclosed that NCs based membranes showed prolonged thrombin and prothrombin clotting times, lessened production of fibrinogen cluster, and greatly suppressed adhesion of blood plasma than a pristine PES membrane. The results also unveiled that PVP-k30/NCs improved the surface properties of the membrane and the urea and creatinine removal increased to 72% and 75% than pure PES membranes. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 513-525, 2019.
    Matched MeSH terms: Povidone/chemistry*
  9. Garg P, Khor WB, Roy A, Tan DT, APAX consortium
    Int Ophthalmol, 2023 Nov;43(11):4151-4162.
    PMID: 37526782 DOI: 10.1007/s10792-023-02816-w
    PURPOSE: To determine current institutional practice patterns for the use of perioperative antibiotics and other measures to prevent infection after cataract surgery in Asia.

    METHODS: An online survey-based study of leading eye institutions in China, Hong Kong, India, Indonesia, Japan, Malaysia, Pakistan, Philippines, Singapore, South Korea, Taiwan, Thailand and Vietnam was conducted. The survey was administered to 26 representative key opinion leaders from prominent tertiary eye institutions that are also national academic teaching institutions in Asia. Survey responses were collated and anonymized during analysis.

    RESULTS: All surveyed institutions used povidone iodine for the preoperative antiseptic preparation of the eye, with notable variations in the concentration of povidone iodine used for conjunctival sac instillation. Preoperative topical antibiotics were prescribed by 61.5% and 69.2% of institutions in low-risk and high-risk cases, respectively. Regarding the use of intra-operative antibiotics, 60.0% and 66.7% of institutions administered intracameral antibiotics in low-risk and high-risk patients, respectively. Postoperative topical antibiotics use patterns were generally very similar in low-risk and high-risk patients. Over half of the institutions (52.2% and 68.0% in low-risk and high-risk patients, respectively) also indicated prolonged postoperative use of topical antibiotics (> 2 weeks). Not all surveyed institutions had established policies/protocols for perioperative antibiotic use in cataract surgery, endophthalmitis surveillance, and/or a monitoring program for emerging antimicrobial resistance.

    CONCLUSION: There are variations in antimicrobial prophylaxis approaches to preoperative, intra-operative and postoperative regimens in cataract surgery in Asia. More evidence-based research is needed to support the development of detailed guidelines for perioperative antibiotic prophylaxis to reduce postoperative infections.

    Matched MeSH terms: Povidone-Iodine/therapeutic use
  10. Sa'adun NN, Subramaniam R, Kasi R
    ScientificWorldJournal, 2014;2014:254215.
    PMID: 25431781 DOI: 10.1155/2014/254215
    Gel polymer electrolytes (GPEs) are developed using poly(1-vinylpyrrolidone-co-vinyl acetate) [P(VP-co-VAc)] as the host polymer, lithium bis(trifluoromethane) sulfonimide [LiTFSI] as the lithium salt and ionic liquid, and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide [EMImTFSI] by using solution casting technique. The effect of ionic liquid on ionic conductivity is studied and the optimum ionic conductivity at room temperature is found to be 2.14 × 10(-6) S cm(-1) for sample containing 25 wt% of EMImTFSI. The temperature dependence of ionic conductivity from 303 K to 353 K exhibits Arrhenius plot behaviour. The thermal stability of the polymer electrolyte system is studied by using thermogravimetric analysis (TGA) while the structural and morphological properties of the polymer electrolyte is studied by using Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction analysis (XRD), respectively.
    Matched MeSH terms: Povidone/analysis; Povidone/chemistry*
  11. Mohamed NA, Ahmad Zainol Hady A, Abdul Aziz AH, Isahak I
    Trop Biomed, 2020 Dec 01;37(4):1141-1145.
    PMID: 33612766 DOI: 10.47665/tb.37.4.1141
    Coronavirus Disease 2019 (COVID-19) has infected more than 8 million people globally since its discovery in December 2019. For COVID-19 prevention, the World Health Organization recommended regular handwashing with soap, cough etiquette, mask wearing and social distancing. However, COVID-19 is rather difficult to contain because of its high transmissibility property. Gargling is effective for reducing infection in the respiratory tract. Most antiseptic gargles have antimicrobial properties against common respiratory pathogens. No published study on the effectiveness of antiseptic gargling among COVID-19 patients has been available to date. This article reviewed available literature on methods and solutions available for gargling and their effect on respiratory tract infections.
    Matched MeSH terms: Povidone-Iodine/administration & dosage; Povidone-Iodine/therapeutic use
  12. Seiffert J, Hussain F, Wiegman C, Li F, Bey L, Baker W, et al.
    PLoS One, 2015;10(3):e0119726.
    PMID: 25747867 DOI: 10.1371/journal.pone.0119726
    Particle size and surface chemistry are potential determinants of silver nanoparticle (AgNP) respiratory toxicity that may also depend on the lung inflammatory state. We compared the effects of intratracheally-administered AgNPs (20 nm and 110 nm; polyvinylpyrrolidone (PVP) and citrate-capped; 0.1 mg/Kg) in Brown-Norway (BN) and Sprague-Dawley (SD) rats. In BN rats, there was both a neutrophilic and eosinophilic response, while in SD rats, there was a neutrophilic response at day 1, greatest for the 20 nm citrate-capped AgNPs. Eosinophilic cationic protein was increased in bronchoalveolar lavage (BAL) in BN and SD rats on day 1. BAL protein and malondialdehyde levels were increased in BN rats at 1 and 7 days, and BAL KC, CCL11 and IL-13 levels at day 1, with increased expression of CCL11 in lung tissue. Pulmonary resistance increased and compliance decreased at day 1, with persistence at day 7. The 20 nm, but not the 110 nm, AgNPs increased bronchial hyperresponsiveness on day 1, which continued at day 7 for the citrate-capped AgNPs only. The 20 nm versus the 110 nm size were more proinflammatory in terms of neutrophil influx, but there was little difference between the citrate-capped versus the PVP-capped AgNPs. AgNPs can induce pulmonary eosinophilic and neutrophilic inflammation with bronchial hyperresponsiveness, features characteristic of asthma.
    Matched MeSH terms: Povidone/analogs & derivatives*; Povidone/toxicity
  13. Hata M, Sato S, Kita K
    Parasitol Int, 2019 Apr;69:99-102.
    PMID: 30543864 DOI: 10.1016/j.parint.2018.12.003
    The growth and the survival of the human malaria parasite Plasmodium falciparum are critically dependent on the functions of the two organelles - the mitochondrion and the apicoplast. However, these two organelles have been known to be difficult to separate from each other when they are released from Plasmodium cell. We have been searching for the conditions with which separation of the mitochondrion and the apicoplast is achieved. In this study, we investigated how the two organelle's separation is affected when the pressure of the nitrogen gas to disrupt the Plasmodium cells by nitrogen cavitation method is lowered from the pressure regularly applied (1200 psi). The parasite cell was sufficiently disrupted even when nitrogen cavitation was carried out at 300 psi. The obtained mitochondrial sample was much less contaminated by DNA compared with the sample prepared using the gas at the regular pressure. After the fractionation by Percoll density gradient, the mitochondrion and the apicoplast from the 300 psi cell lysate exhibited different separation profiles. This is the first experimental evidence that indicates the mitochondrion and the apicoplast of P. falciparum are separable from each other.
    Matched MeSH terms: Povidone
  14. Moradihamedani P, Abdullah AH
    Water Sci Technol, 2017 May;75(10):2422-2433.
    PMID: 28541950 DOI: 10.2166/wst.2017.122
    Neat cellulose acetate (CA) and CA/polysulfone (PSf) blend ultrafiltration membranes in the presence of polyvinylpyrrolidone as a pore former were prepared via a phase inversion technique. The prepared membranes were characterized by Fourier transform infrared, scanning electron microscopy, mechanical strength, water content, porosity, permeate flux and heavy metals (Pb2+, Cd2+, Zn2+ and Ni2+) rejection to comprehend the impact of polymer blend composition and additive on the properties of the modified membranes. The water flux expanded by increasing of PSf content in the polymer composition. CA/PSf (60/40) had the highest flux among prepared membranes. Prepared blend membranes were able to remove heavy metals from water in the following order: Pb2+ > Cd2+ > Zn2+ > Ni2+. The CA/PSf (80/20) blend membrane had great performance among prepared membranes due to the high heavy metals removal and permeate flux.
    Matched MeSH terms: Povidone
  15. Agi A, Junin R, Alqatta AYM, Gbadamosi A, Yahya A, Abbas A
    Ultrason Sonochem, 2019 Mar;51:214-222.
    PMID: 30401623 DOI: 10.1016/j.ultsonch.2018.10.023
    Ultrafiltration has been proven to be very effective in the treatment of oil-in-water emulsions, since no chemical additives are required. However, ultrafiltration has its limitations, the main limits are concentration polarization resulting to permeate flux decline with time. Adsorption, accumulation of oil and particles on the membrane surface which causes fouling of the membrane. Studies have shown that the ultrasonic is effective in cleaning of fouled membrane and enhancing membrane filtration performance. But the effectiveness also, depends on the selection of appropriate membrane material, membrane geometry, ultrasonic module design, operational and processing condition. In this study, a hollow and flat-sheet polyurethane (PU) membranes synthesized with different additives and solvent were used and their performance evaluated with oil-in-water emulsion. The steady-state permeate flux and the rejection of oil in percentage (%) at two different modes were determined. A dry/wet spinning technique was used to fabricate the flat-sheet and hollow fibre membrane (HFMs) using Polyethersulfone (PES) polymer base, Polyvinylpyrrolidone (PVP) additive and N, N-Dimethylacetamide (DMAc) solvent. Ultrasonic assisted cross-flow ultrafiltration module was built to avoid loss of ultrasonic to the surrounding. The polyurethane (PU) was synthesized by polymerization and sulphonation to have an anionic group (-OH; -COOH; and -SO3H) on the membrane surface. Changes in morphological properties of the membrane had a significant effect on the permeate flow rate and oil removal. Generation of cavitation and Brownian motion by the ultrasonic were the dominant mechanisms responsible for ultrafiltration by cracking the cake layers and reducing concentration polarization at the membrane surface. The percentage of oil after ultrafiltration process with ultrasonic is about 90% compared to 49% without ultrasonic. Ultrasonic is effective in enhancing the membrane permeate flux and controlling membrane fouling.
    Matched MeSH terms: Povidone
  16. Gharibshahi E, Saion E, Ashraf A, Gharibshahi L
    Appl Radiat Isot, 2017 Dec;130:211-217.
    PMID: 29028581 DOI: 10.1016/j.apradiso.2017.09.012
    Gamma radiolytic synthesis was used to produce size-controlled spherical platinum nanoparticles from an aqueous solution containing platinum tetraammine and polyvinyl pyrrolidone. The structural characterizations were performed using X-ray diffraction, and transmission electron microscopy. The transmission electron microscopy was used to determine the average particle diameter, which decreased from 4.4nm at 80kGy to 2.8nm at 120kGy. The UV-visible absorption spectrum was measured and found that platinum nanoparticles exhibit two steady absorption maxima in UV regions due to plasmonic excitation of conduction electrons, which blue shifted to lower wavelengths with a decrease in particle size. We consider the conduction electrons of platinum nanoparticles to follow Thomas-Fermi-Dirac-Weizsacker atomic model that they are not entirely free but weakly bounded to particles at lower-energy states {n = 5, l = 2 or 5d} and {n = 6, l = 0 or 6s}, which upon receiving UV photon energy the electrons make intra-band quantum excitations to higher-energy states allowed by the principles of quantum number that results the absorption maxima. We found an excellent agreement between the experimental and theoretical results, which suggest that the optical absorption of metal nanoparticles could be fundamentally described by a quantum mechanical interpretation, which could be more relevant to photo-catalysis and heterogeneous catalysis.
    Matched MeSH terms: Povidone
  17. Abedini A, Saion E, Larki F, Zakaria A, Noroozi M, Soltani N
    Int J Mol Sci, 2012;13(9):11941-53.
    PMID: 23109893 DOI: 10.3390/ijms130911941
    Colloidal Cu@CuAlO(2)-Al(2)O(3) bimetallic nanoparticles were prepared by a gamma irradiation method in an aqueous system in the presence of polyvinyl pyrrolidone (PVP) and isopropanol respectively as a colloidal stabilizer and scavenger of hydrogen and hydroxyl radicals. The gamma irradiation was carried out in a (60)Co gamma source chamber with different doses up to 120 kGy. The formation of Cu@CuAlO(2)-Al(2)O(3) nanoparticles was observed initially by the change in color of the colloidal samples from colorless to brown. Fourier transform infrared spectroscopy (FTIR) confirmed the presence of bonds between polymer chains and the metal surface at all radiation doses. Results of transmission electron microscopy (TEM), energy dispersive X-ray spectrometry (EDX), and X-ray diffraction (XRD) showed that Cu@CuAlO(2)-Al(2)O(3) nanoparticles are in a core-shell structure. By controlling the absorbed dose and precursor concentration, nanoclusters with different particle sizes were obtained. The average particle diameter increased with increased precursor concentration and decreased with increased dose. This is due to the competition between nucleation, growth, and aggregation processes in the formation of nanoclusters during irradiation.
    Matched MeSH terms: Povidone/chemistry
  18. Shukrimi A, Sulaiman AR, Halim AY, Azril A
    Med J Malaysia, 2008 Mar;63(1):44-6.
    PMID: 18935732 MyJurnal
    Honey dressing has been used to promote wound healing for years but scanty scientific studies did not provide enough evidences to justify it benefits in the treatment of diabetic foot ulcers. We conducted a prospective study to compare the effect of honey dressing for Wagner's grade-II diabetic foot ulcers with controlled dressing group (povidone iodine followed by normal saline). Surgical debridement and appropriate antibiotics were prescribed in all patients. There were 30 patients age between 31 to 65-years-old (mean of 52.1 years). The mean healing time in the standard dressing group was 15.4 days (range 9-36 days) compared to 14.4 days (range 7-26 days) in the honey group (p < 0.005). In conclusion, ulcer healing was not significantly different in both study groups. Honey dressing is a safe alternative dressing for Wagner grade-II diabetic foot ulcers.
    Matched MeSH terms: Povidone-Iodine/therapeutic use*
  19. Azran YM, Idris B, Rusnah M, Rohaida CH
    Med J Malaysia, 2004 May;59 Suppl B:79-80.
    PMID: 15468828
    The paper presents the effect of sintering temperature on the physical properties of porous hydroxyapatite (HAp In this study, the HAp was prepared using polymeric sponge techniques with different binder concentrations. The sintering process was carried out in air for temperature ranging from 1200 degrees C to 1600 degrees C. Different physical properties namely density and porosity were observed at different sintering temperatures. The HAp prepared with higher PVP binder showed a slightly decreased in apparent density with increasing sintering temperature, while those HAp prepared with lower PVP showed a slightly increase in apparent density with increasing sintering temperature. The total porosity was found to be approximately constant in the whole sintering temperature range. However, closed porosity decreases with increasing sintering temperature for HAp prepared by lower binder concentration. On the other hand, the HAp prepared by higher binder concentrations showed increasing closed porosity with increasing sintering temperature. Other features such as the influence of sintering temperatures on grain and strut would also be presented in this paper.
    Matched MeSH terms: Povidone/chemical synthesis*
  20. Botelho DJ, Leo BF, Massa CB, Sarkar S, Tetley TD, Chung KF, et al.
    Nanotoxicology, 2016;10(1):118-27.
    PMID: 26152688 DOI: 10.3109/17435390.2015.1038330
    Multiple studies have examined the direct cellular toxicity of silver nanoparticles (AgNPs). However, the lung is a complex biological system with multiple cell types and a lipid-rich surface fluid; therefore, organ level responses may not depend on direct cellular toxicity. We hypothesized that interaction with the lung lining is a critical determinant of organ level responses. Here, we have examined the effects of low dose intratracheal instillation of AgNPs (0.05 μg/g body weight) 20 and 110 nm diameter in size, and functionalized with citrate or polyvinylpyrrolidone. Both size and functionalization were significant factors in particle aggregation and lipid interaction in vitro. One day post-intratracheal instillation lung function was assessed, and bronchoalveolar lavage (BAL) and lung tissue collected. There were no signs of overt inflammation. There was no change in surfactant protein-B content in the BAL but there was loss of surfactant protein-D with polyvinylpyrrolidone (PVP)-stabilized particles. Mechanical impedance data demonstrated a significant increase in pulmonary elastance as compared to control, greatest with 110 nm PVP-stabilized particles. Seven days post-instillation of PVP-stabilized particles increased BAL cell counts, and reduced lung function was observed. These changes resolved by 21 days. Hence, AgNP-mediated alterations in the lung lining and mechanical function resolve by 21 days. Larger particles and PVP stabilization produce the largest disruptions. These studies demonstrate that low dose AgNPs elicit deficits in both mechanical and innate immune defense function, suggesting that organ level toxicity should be considered.
    Matched MeSH terms: Povidone/pharmacology
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