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PubMed2006

Effect of an oily calcium hydroxide suspension on early wound healing after nonsurgical periodontal therapy.

The purpose of the present study was to evaluate clinically the effect of an oily calcium hydroxide suspension on early wound healing after nonsurgical periodontal therapy. A total of 19 patients with chronic periodontitis were enrolled in the study. Each subject had three sites in each of two contra-lateral jaw quadrants with a probing pocket depth (PPD) of > or =5 mm and bleeding on probing (BoP+). All teeth received scaling and root planing under local anesthesia followed by irrigation with sterile saline. An oily calcium hydroxide suspension (Osteoinductal) was applied subgingivally to the test sites at random. All sites were reexamined after 1, 2 [gingival index (GI) and BoP], and 3 weeks (GI, BoP, and PPD). Treatment success was defined as no signs of GI (GI=0), no BoP (BoP-), and pocket closure (PPD< or =4 mm). At all three different points in time, there were improvements in both GI and BoP at the control and test sites, which were in favor of the test therapy (p<0.05). For PPD change, no differences were found between the test and the control sites. The results of the study suggest that the topical application of an oily calcium hydroxide suspension (Osteoinductal), after nonsurgical periodontal therapy, improves early periodontal wound healing.

Administration, Topical↗
PubMed1984

Imidazole, imidazolate, and hydroxide complexes of (protoporphyrin IX)iron(III) and its dimethyl ester as model systems for ferric hemoproteins: electron paramagnetic resonance and electronic spectral study.

The EPR and electronic spectral changes upon titration of systems consisting of (protoporphyrin IX)iron(III) chloride (Fe(PPIX)Cl) or its dimethyl ester (Fe-(PPIXDME)Cl) and imidazole derivatives with tetrabutylammonium hydroxide solution have been measured at 77 and 298 degrees K in various solvents. The EPR and electronic spectra of the melt of Fe(PPIXDME)Cl in imidazole derivatives have been also measured. The imidazole derivatives studied here were imidazole and 4-methyl-, 4-phenyl-, 2-methyl-, 2,4-dimethyl-, 1-methyl-, and 1-acetylimidazole. The spectral changes upon addition of hydroxide were markedly different between the systems containing NH imidazoles (BH), with a dissociable proton, and those containing NR imidazoles (BR), without it. In the former systems, five spectral species were successively formed at 77 degrees K and were assigned to following complexes: [Fe(P)(BH)2]+, Fe(P)(BH)(B), [Fe(P)(B)2]-, Fe(P)(BH)(OH), and [Fe(P)(B)(OH)]-, where P is PPIX or PPIXDME. In the latter systems, initial complex, [Fe(P)(BR)2]+, was found to be changed to final complex, Fe(P)(BR)(OH), through an intermediate at 77 degrees K. At 298 degrees K, both systems were found to react with hydroxide to finally form Fe(P)(OH). The crystal field parameters were evaluated using the EPR g values in low-spin complexes studied here and in hemoproteins. The five regions corresponding to five low-spin complexes could be distinguished in crystal field diagrams.

Chemical Phenomena↗
PubMed1992

Zinc hydroxide stimulates superoxide production by rat alveolar macrophages.

The effect of zinc hydroxide on superoxide (O2-) production by rat alveolar macrophages was determined by chemiluminescence and by cytochrome c reduction. Zinc ions had no effect on the chemiluminescence of unstimulated alveolar macrophages. By contrast, zinc hydroxide (ZnOH2), a neutralized form of zinc ions, increased the chemiluminescence level and O2- release. Increased O2- release was inhibited by pertussis toxin, isoquinoline sulfonamide and pretreatment with EGTA. These findings indicate that zinc hydroxide formation from zinc compounds can stimulate the O2- production by alveolar macrophages by receptor-mediated and Ca(2+)-dependent process.

Animals↗
PubMed1987

A new redox loop formality involving metal-catalysed hydroxide-ion translocation. A hypothetical Cu loop mechanism for cytochrome oxidase.

A new hypothetical type of redox loop is described, which translocates hydroxide instead of protons. Conventional protonmotive redox loops use carriers of protons with electrons (e.g. QH2/Q systems) to couple electron transfer to the translocation of protons. The putative hydroxidemotive redox loop uses carriers of hydroxide ions against electrons (e.g. transition-metal centres) to couple electron transfer to the translocation of hydroxide ions. This simple idea leads to the proposal of a hydroxidemotive Cu loop mechanism that may possibly be applicable to the CuA or CuB centre of cytochrome oxidase, and might thus account for the coupling of electron transfer to net proton translocation in that osmoenzyme.

Copper↗
PubMed1988

The tissue reactions after capping of dog teeth with calcium hydroxide experimentally crammed into the pulp space.

The pulps of 48 permanent dog teeth, incisors and canines, were evaluated histopathologically after capping treatment with pure calcium hydroxide placed by two methods: the experimental method, in which the calcium hydroxide was crammed into the pulpal space via the exposure site, and the usual method of direct pulp capping (controls). The results were recorded after periods of 2, 15, and 69 days. The healing process with hard-tissue formation was more evident in the experimentally capped teeth, despite the fact that pulpal necrosis occurred in a higher proportion of these teeth after use of this method of placement of the calcium hydroxide.

Animals↗
PubMed1989

Physical properties of calcium hydroxide and glass-ionomer base and lining materials.

Compressive, diametral tensile and flexural strengths, moduli of elasticity, pH, and acid solubility values were compared for six calcium hydroxide cements, seven glass-ionomer cements, and one calcium aluminate cement. Results indicated that the glass-ionomer materials were generally stronger than the calcium hydroxide liners. Prisma VLC Dycal showed the lowest value for modulus of elasticity and the least acid solubility. The glass-ionomer materials were initially acidic, reaching a final pH between 5.4 and 7.3, whereas the calcium hydroxide and calcium aluminate cements were strongly alkaline at all time intervals.

Calcium Hydroxide↗
PubMed1990

Experimental study on the biocompatibility of lining cements based on glass ionomer as compared with calcium hydroxide.

An in vitro study with cultured fibroblast-like cells of the pulp was used to assess the biological tolerance of three lining cements based on glass ionomers and two hard liners containing calcium hydroxide. The results indicate that strong cytotoxic components of all g.-i. lining cements tested can be eluted even after hardening for 48 hours. In contrast, the two liners based on calcium hydroxide proved to be of greater biocompatibility after the same hardening period. Therefore, use of calcium hydroxide liners is recommended for placement in deep cavities near the pulp.

Animals↗
PubMed1992

Induction of protective class I MHC-restricted CTL in mice by a recombinant influenza vaccine in aluminium hydroxide adjuvant.

Induction of class I MHC-restricted cytotoxic T lymphocyte (CTL) responses by soluble proteins or peptides requires complex adjuvants or carrier systems which are not licensed for use with human vaccines. The data presented in this report show that vaccination with a highly purified recombinant influenza protein antigen in aluminium hydroxide adjuvant, the only adjuvant currently licensed for clinical use, elicited class I restricted CTL and protection from lethal challenge with H1N1 and H2N2 viruses. The antigen (D protein, SK&F 106160) is produced by expression of H1N1 influenza virus-derived cDNA (strain A/PR/8/34) in Escherichia coli, and is composed of the first 81 N-terminal amino acids (aa) of the non-structural protein 1 (NS1) fused via a nine nucleotide non-viral linker sequence to the 157 C-terminal aa of the haemagglutinin 2 subunit (HA2). Previous work by Kuwano et al demonstrated that in vitro stimulation of spleen cells from influenza virus-primed mice, with a partially purified preparation of the D protein, selected for CD8+ CTL clones which facilitated lung clearance of H1N1 and H2N2 viruses. In the current study, these results were extended by studying the responses of mice actively immunized with highly purified D protein in the presence or absence of adjuvants. Vaccination of CB6F1 (H-2dxb) mice with D protein in aluminum hydroxide or Freund's complete adjuvant generated H1N1 cross-reactive, H-2d-restricted, CD8+ CTL directed against an immunodominant HA2 epitope (aa 189-199). D protein without adjuvant did not elicit CTL, regardless of the route of injection. However, long-lived (greater than 6 months) splenic memory CTL were elicited by boosting mice intraperitoneally (i.p.) with the D protein in the absence of adjuvant. In mice injected subcutaneously with D protein in aluminium hydroxide at weeks 0 and 3, survival was increased relative to controls up to 16 weeks beyond the second vaccination, after which time additional boosting was required for protection. Studies in H-2b and H-2k mice vaccinated with the D protein showed that induction of CD4+ T-cell or antibody responses, in the absence of CD8+ CTL, did not correlate with protection. Passive transfer of immune sera from CB6F1 mice was also not protective. This prototype H1N1 recombinant subunit vaccine in aluminium adjuvant should directly address the feasibility of achieving a protective cell-mediated immune response in human influenza.

Adjuvants, Immunologic↗
PubMed1996

Treatment of aluminium hydroxide adjuvant to optimize the adsorption of basic proteins.

Aluminium hydroxide adjuvant has an isoelectric point (i.e.p.) of ca 11 and is a good adsorbent for acidic proteins due to the contribution of electrostatic attractive forces. However, electrostatic repulsive forces reduce its ability to adsorb basic proteins. Pretreatment of aluminium hydroxide adjuvant with carefully selected concentrations of phosphate anion reduces the positive surface charge which exists at pH 7.4. Treatment with higher concentrations of phosphate anion produces a negative surface charge. The adsorption of lysozyme (i.e.p = 11.1) was found to be directly related to the concentration of phosphate anion used to pretreat the aluminium hydroxide adjuvant.

Adjuvants, Immunologic↗
PubMed1984

Aluminium concentrations in the brain and bone of rats fed citric acid, aluminium citrate or aluminium hydroxide.

Male Sprague-Dawley rats were treated daily by gastric intubation (6 days/wk) with 100 mg aluminium/kg body weight in the form of aluminium hydroxide (9 wk) or aluminium citrate (4 wk), with citric acid (4 wk) or with tap-water (control, 9 wk). Young adult and aged Wistar rats were treated with 100 mg aluminium/kg body weight as aluminium hydroxide or with carboxymethylcellulose (vehicle controls). The cerebral cortex, hippocampus, cerebellum and samples of bone from each rat were analysed for aluminium, after digestion with nitric acid, using graphite furnace atomic absorption spectroscopy. The mean aluminium concentrations detected in the control Sprague-Dawley rats were 0.013-0.022 microgram/g wet weight in the various brain regions and 0.355 microgram/g in the bone. No significant increase in tissue aluminium concentrations was observed in Sprague-Dawley or Wistar rats after treatment with aluminium hydroxide. However the rats treated with aluminium citrate showed significantly increased concentrations of aluminium in all the brain regions studied (0.057-0.121 microgram A1/g) and in the bone (12.9 micrograms A1/g). Elevated aluminium concentrations in the cerebral cortex and bone were also observed in the animals fed citric acid suggesting possible absorption of the citrate chelate presumably formed with the traces of aluminium present in the diet.

Aluminum↗
PubMed1990

Adaptation of two different calcium hydroxide bases under a composite restoration.

A preliminary scanning electron microscope (SEM) study was carried out to investigate how the adaptation of two calcium hydroxide bases (one chemically cured, one light cured) was affected by the polymerization contraction of a supervening light-cured composite resin restoration. Occlusal cavities were prepared in 40 sound extracted human premolars, divided into two equal groups. In the first group a chemically cured calcium hydroxide (Dycal, De Trey Dentsply, Konstanz, FRG) was placed as a base. In the second group a new light-cured calcium hydroxide product (Prisma VLC Dycal, De Trey Dentsply) was used. The restorations were completed with an acid-etched, incrementally placed composite resin. The specimens were sectioned vertically and debrided. A replica was made of each half-tooth. The interfaces between composite resin/base and base/dentine were viewed and photographed in the SEM. The marginal adaptation at these two interfaces was classified into three categories according to the extent of the gaps that were observed. Prisma VLC Dycal base was found to be pulled away from the dentine floor of the cavity as a result of an apparent adhesion to the composite resin during polymerization contraction. Dycal was better adapted to the cavity floor than Prisma VLC Dycal. Disorganization of the resin-bonded Prisma VLC Dycal was minimal even after acid etching the enamel, sectioning and ultrasonic debridement. Dycal appeared to be more friable, and occasionally exhibited marked disorganization as a result of these procedures.

Acid Etching, Dental↗
PubMed2006

Investigation by bioassay of the efficacy of sodium hydroxide treatment on the inactivation of mouse-adapted scrapie.

Sodium hydroxide (NaOH) has been shown to reduce the infectivity of transmissible spongiform encephalopathy (TSE) agents. This study investigated the efficacy of sodium hydroxide at 0.1M, 0.25M and 0.5M concentrations for the inactivation of mouse-adapted scrapie strain ME7. Times and temperatures modelled conditions used in an industrial plasma fractionation plant for sanitisation of ultrafilters, and the sodium hydroxide component of Clean In Place sanitisation. The concentration of scrapie ME7 brain homogenate in NaOH test solutions was 1% (w/v). At the end of incubation periods, the samples were adjusted to neutral pH prior to intracerebral inoculation into mice for bioassay. The conditions of 0.1M NaOH at 60 degrees C for 2min and 0.25M NaOH at 30 degrees C for 60min were found to inactivate 3.96 and 3.93logs of scrapie, respectively. Use of 0.5M NaOH at 30 degrees C for 60 or 75min was found to inactivate >or=4.23 and 4.15logs of scrapie. This indicates that the use of these conditions in an industrial process would substantially reduce prion infectivity.

Adaptation, Physiological↗
PubMed2004

Ion chromatographic determination of hydroxide ion on monolithic reversed-phase silica gel columns coated with nonionic and cationic surfactants.

The determination of hydroxide by ion chromatography (IC) is demonstrated using a monolithic octadecylsilyl (ODS)-silica gel column coated first with a nonionic surfactant (polyoxyethylene (POE)) and then with a cationic surfactant (cetyltrimethylammonium bromide (CTAB)). This stationary phase, when used in conjunction with a 10 mmol/l sodium sulfate eluent at pH 8.2, was found to be suitable for the rapid and efficient separation of hydroxide from some other anions, based on a conventional ion-exchange mechanism. The peak directions and detection responses for these ions were in agreement with their known limiting equivalent ionic conductance values. Under these conditions, a linear calibration plot was obtained for hydroxide ion over the range 16 micromol/l to 15 mmol/l, and the detection limit determined at a signal-to-noise ratio of 3 was 6.4 micromol/l. The double-coated stationary phase described above was shown to be superior to a single coating of cetyltrimethylammonium bromide alone, in terms of separation efficiency and stability of the stationary phase. A range of samples comprising solutions of some strong and weak bases was analyzed by the proposed method and the results obtained were in good agreement with those obtained by conventional potentiometric pH measurement.

Chromatography, Ion Exchange↗
PubMed2006

Curcumin/turmeric solubilized in sodium hydroxide inhibits HNE protein modification--an in vitro study.

Free radical mediated lipid peroxidation has been implicated in multiple diseases. A major oxidation by-product of this deleterious process is 4-hydroxy-2-nonenal (HNE). HNE is cytotoxic, mutagenic and genotoxic and is involved in disease pathogenesis. Curcumin, a non-steroidal anti-inflammatory agent (occurring as the yellow pigment found in the rhizomes of the perennial herb Curcuma longa known as turmeric), has emerged as the newest "nutraceutical" agent that has been shown to be efficacious against colon cancer and other disorders, including correcting cystic fibrosis defects. Since curcumin has been reported to have anti-oxidant properties we hypothesized that it will inhibit HNE-modification of a protein substrate. Using an ELISA that employed HNE-modification of solid phase antigen following immobilization, we found that the curcumin solubilized in dilute alkali (5mM sodium hydroxide, pH 11) inhibited HNE-protein modification by 65%. Turmeric also inhibited HNE-protein modification similarly (65%) but at a much lower alkali level (130muM sodium hydroxide, pH 7.6). Alkali by itself (5mM sodium hydroxide, pH 11) was found to enhance HNE modification by as much as 267%. Curcumin/turmeric has to inhibit this alkali enhanced HNE-modification prior to inhibiting the normal HNE protein modification induced by HNE. Thus, inhibition of HNE-modification could be a mechanism by which curcumin exerts its antioxidant effects. The pH at which the inhibition of HNE modification of substrate was observed was close to the physiological pH, making this formulation of curcumin potentially useful practically.

Aldehydes↗
PubMed2003

Displaced calcium hydroxide paste causing inferior alveolar nerve paraesthesia: report of a case.

A patient presented with an intraoral red, painful, and hard swelling in the lower right jaw. Radiographs showed a 2 x 1 cm area of radiopaque material surrounding the apex of the second premolar. The material, according to the patient's dentist, was calcium hydroxide paste used as a temporary dressing material in the root canal. The patient developed paraesthesia in her lower lip probably due to a neurotoxic effect caused by calcium hydroxide. The foreign material was surgically excavated from the spongious bone, directly adjacent to the nerve, and the patient later regained her sensation in the lip. A histopathological analysis revealed necrosis, deposits of foreign bodies, and inflammatory cells and foreign-body giant cells. This report illustrates the toxicity and adjacent clinical symptoms of calcium hydroxide paste when displaced into bone tissue close to the alveolar inferior nerve. It also demonstrates the benefits of removing such displaced material before symptoms progress.

Calcium Hydroxide↗
PubMed2006

The effect of sodium hypochlorite application on the success of calcium hydroxide pulpotomy in primary teeth.

OBJECTIVE: The aim of this study was to evaluate the effects of 3% sodium hypochlorite (NaOCl) used as a hemostatic agent on the outcome of calcium hydroxide pulpotomies of primary teeth. STUDY DESIGN: A total of 18 primary molars with advanced caries and root resorption of approximately half the root length were randomly placed into 2 groups. Conventional calcium hydroxide pulpotomies were performed on teeth in both groups; however, a cotton pellet saturated with 3% sodium hypochlorite was applied to teeth in the treatment group for 30 seconds before the pulpotomy to control hemorrhage. After the extraction of the teeth, they were examined histologically. RESULTS: In the histologic evaluation it was found that none of the specimens in the control group showed necrosis and 1 specimen in the treatment group showed partial necrosis. CONCLUSION: It was found that the use of 3% NaOCl as a hemostatic agent had no effect on the outcome of calcium hydroxide pulpotomies with the given concentration and timing of the NaOCl treatment and the given observation period.

Adolescent↗
PubMed2004

Effect of microenvironment pH of aluminum hydroxide adjuvant on the chemical stability of adsorbed antigen.

The rate of acid-catalyzed hydrolysis of glucose-1-phosphate (G1P) when adsorbed to aluminum hydroxide adjuvant was significantly slower than the rate of hydrolysis of a solution of G1P at the same pH. It was concluded that the positively charged aluminum hydroxide adjuvant (iep 11.4) electrostatically attracted anions including hydroxyls to form a double layer surrounding the adjuvant particles. Thus, the pH of the microenvironment surrounding the aluminum hydroxide adjuvant was higher than the bulk pH. Adsorbed G1P hydrolyzed at a rate associated with the pH of the microenvironment of the surface of the adjuvant rather than with the pH of the bulk solution. Comparison of the rate constant for the hydrolysis of adsorbed G1P to the pH-stability profile of G1P in solution revealed that adsorbed G1P hydrolyzed at a rate associated with a pH that was approximately two pH units higher than the bulk pH. The results suggest that the chemical stability of antigens that degrade by pH-dependent mechanisms can be optimized by modifying the surface charge of the aluminum-containing adjuvant to produce the pH of maximum stability in the microenvironment of the adjuvant.

Absorption↗
PubMed2005

Aluminium hydroxide-induced granulomas in pigs.

The effect of intramuscular injection of 40 mg/2 ml aluminium hydroxide in the neck of pigs was examined in a number of ways. The investigation followed repeated slaughterhouse reports, according to which 64.8% of pigs from one particular farm were found at slaughter to have one or more nodules in the muscles of the neck (group slaughtered). The pigs had been injected with a vaccine containing 40 mg/2 ml dose of aluminium hydroxide as adjuvant. Research consisted of two phases: first, an epidemiological study was carried out, aimed at determining the risk factors for the granulomas. The results indicated that the vaccine was to be held responsible for the formation of granulomas. A clinical trial was then performed to further substantiate the initial hypothesis, by comparing pigs, which were aseptically inoculated twice with either the original vaccine or the adjuvant alone (groups vaccine and adjuvant) to pigs inoculated twice with apyrogenic bi-distilled water (group water) and to pigs inoculated once with the adjuvant and once with apyrogenic bi-distilled water (group adjuvant/water). Both studies agreed in their conclusions, which indicate that the high amount of aluminium hydroxide was the cause of the granulomas.

Adjuvants, Immunologic↗