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At least 19 recordsLinked to original sources
PubMed1977

The bio-availability of beta-acetyldigoxine alone and combined with aluminum hydroxide and magnesium hydroxide (Alucol).

The bio-availability of Novodigal (beta-acetyldigoxine) alone and applied together with Alucol (aluminum hydroxide, magnesium hydroxide) was studied in six healthy probands. Bio-availability parameters were calculated from the areas under the plasma concentration curves and from the comparison of the blood levels after absorption during steady state. There was no significant difference between the bio-availability of beta-acetyldigoxine alone and that of the combination with Alucol. Thus, beta-acetyldigoxine combined with antacids of the aluminum hydroxide and magnesium hydroxide type can be applied in the same dosage as usual since no decrease of effect has to be apprehended.

Adult↗
PubMed1975

[Dynamic comparative study of the intraalveolar cell population after intratracheal injection of beryllium hydroxide and aluminum hydroxide in the rat].

A sequential quantitative analysis of free alveolar cells was performed on S.P.F. rats after intratracheal injection of Be (OH)2 and Al (OH)3. The induced lesions were entirely restored 20 days after the initial injection. Beryllium hydroxide inhibited DNA synthesis in the free alveolar macrophages and the transeptal cellular flow could be evidenced. Aluminium hydroxide increased the number of free cells without inhibiting DNA synthesis. Quantitative variations of polymorphonuclears, lymphocytes and macrophages were correlated with changes in the alveolar environment. A strong direct correlation between the number of lymphocytes and DNA synthetizing macrophages was shown out. This reaction was not observed in beryllium treated rats.

Aluminum↗
PubMed1977

Relationship between zero point of charge and solubility product for hydroxides of polyvalent cations.

The zero point of charge (ZPC) of slightly soluble compounds is the pH at which their particles suspended in water have zero charge. The ZPC values of slightly soluble hydroxides were compared with their solubility product in the form of its negative logarithm, pKSP, and with th pH of their suspensions in pure water, pHSP, which is a function of pKSP. The ZPC-pKSP relation was nonlinear while the ZPC-pHSP relation was linear. Either equation can used to estimate the ZPC value of a hydroxide from its solubility product. The ZPC of a given hydroxide was higher than its pHSP because polyvalent cations are more extensively adsorbed and less extensively desorbed from the particle surface than the monovalent hydroxide ion. At the pHSP, there are equivalent amounts of the cation and of the hydroxide anion in solution, but the surface layer of the hydroxide particle contains an excess cation on an equivalent basis. This imbalance confers a positive charge to the particle. The solubility product of aluminum hydroxide, redetermined at 25 degrees by means of pH measurements, was 8 X 10(-33). Its ZPC, redetermined by microelectrophoresis, was 8.5 +/- 0.1.

Chemical Phenomena↗
PubMed1977

Aluminium hydroxide in bile-salt diarrhoea.

The treatment of choleraic diarrhoea remains a problem. Cholestyramine is effective but long-term treatment is often impracticable. In-vitro studies have shown that aluminium hydroxide has bile-acid-binding properties comparable with those of cholestyramine. The bile-acid-binding properties of aluminium hydroxide have now been investigated in vivo and applied to the treatment of patients with choleraic diarrhoea. Aluminium hydroxide increased the faecal bile-salt concentration of patients with a normal bowel habit whereas magnesium hydroxide had no effect. Eight patients with severe choleraic diarrhoea were treated with aluminium-hydroxide suspension: bowel motion became less frequent and daily faecal weight fell.

Adult↗
PubMed1976

Structure of aluminum hydroxide gel I: initial precipitate.

The initial aluminum hydroxide gel precipitate resulting from the reaction of aluminum chloride or aluminum sulfate with ammonium hydroxide is shown by potentiometric titration, chemical analysis, and the ratio of bound hydroxide to aluminum to fit a polymer model described previously. The formation of polynuclear hydroxyaluminum particles is treated as a stepwise process involving a deprotonation-dehydration mechanism, which results in the formation of six-membered rings; these rings may further coalesce by the same mechanism. The aluminum hydroxide gel precipitated from aluminum chloride can be represented by the formula Al(OH)2.55(Cl)0.45 and probably exists as a polymer of 10 fused six-membered rings. The aluminum hydroxide gel precipitated from aluminum sulfate can be represented by the formula Al(OH)2.30(SO4)0.35. This species probably exists as a polymer of three fused six-membered rings.

Aluminum↗
PubMed1979

Effect of interaction of aluminum hydroxycarbonate gel and magnesium hydroxide gel on acid neutralization.

Acid neutralization by mixtures of aluminum hydroxycarbonate gel and magnesium hydroxide gel differs from the sum of the acid neutralization of each gel. Acid neutralization by magnesium hydroxide gel in the mixture is not observed until after a substantial portion of the aluminum hydroxycarbonate gel has reacted with acid, even though magnesium hydroxide gel is the faster reacting of the two gels. It is hypothesized that amorphous aluminum hydroxycarbonate forms a coating on the crystalline magnesium hydroxide particles due to electrostatic attraction. This coating prevents protons from reaching the highly reactive magnesium hydroxide until the coating is dissolved by the acid neutralization of aluminum hydroxycarbonate.

Acids↗
PubMed1976

Active immobilized antibiotics based on metal hydroxides.

The water-insoluble hydroxides of zirconium (IV), titanium (IV), titanium (III), iron (II), vanadium (III), and tin (II) have been used to prepare insoluble derivatives of a cyclic peptide antibiotic by a facile chelation process. Testing of the antibacterial activities of the products against two gram-positive and two gram-negative bacteria showed that in the majority of cases the water-insoluble antibiotics remained active against those bacteria susceptible to the parent antibiotic. The power of the assay system has been extended by the novel use of colored organisms to aid determinations where the growth of normal organisms could not be distinguished from the appearance of the supporting material. Insoluble derivatives of neomycin, polymyxin B, streptomycin, ampicillin, penicillin G, and chloramphenicol were prepared by chelation with zirconium hydroxide, and these derivatives similarly reflected the antibacterial activities of the parent compounds. Several of the metal hydroxides themselves possess antibacterial activity due to complex formation with the bacteria. However, the use of selected metal hydroxides can afford a simple, inexpensive, and inert matrix for antibiotic immobilization, resulting in an antibacterial product that may possess slow-release properties. The mechanisms by which the metal hydroxide-antibiotic association-dissociation may occur are discussed.

Anti-Bacterial Agents↗
PubMed1978

Effect of oral administration of calcium carbonate, aluminum hydroxide gel and dihydrotachysterol on renal acidosis.

The effects of oral administration of calcium carbonate, aluminum hydroxide gel, dihydrotachysterol (DHT) and sodium bicarbonate on metabolic acidosis and plasma calcium and phosphate were studied in 7 patients with chronic renal failure. Single administration of calcium carbonate alleviated the acidosis and increased the urinary bicarbonate excretion. These effects were potentiated when aluminum hydroxide gel was administered in combination with calcium carbonate. The plasma calcium was increased by this combination therapy. The effects of these two agents on acidosis and plasma calcium were further enhanced by the additional administration of DHT. Urinary bicarbonate excretion was less during the treatment with aluminum hydroxide gel and calcium carbonate than with aluminum hydroxide gel and sodium bicarbonate, when the excretions were compared at the similar concentrations of plasma bicarbonate. Aluminum hydroxide gel and DHT are likely to enhance the effect of calcium carbonate, which works as an alkalinizing salt on acidosis, probably through increasing calcium absorption in the intestine. And the three agents suppress the leak of bicarbonate into the urine contributing to the improvement of acidosis.

Acidosis↗
PubMed1975

Reaction of the human dental pulp to silver amalgam restorations. The modifying effect of treatment with calcium hydroxide.

Cavities were prepared in 43 bicuspid teeth using two general categories of cavity depth. In the "deep" cavities the bottom was placed in the inner third of the dentin. In the "intermediate depth" cavities the bottom was positioned in the middle third of the dentin. The bottom of the cavities was either rubbed with calcium hydroxide, covered with calcium hydroxide, or left unlined before filling according to the wet amalgam technique. The teeth were extracted after 1 week and examined histologically. All cases, except 2 with deep and 1 with intermediate depth rubbed cavities, showed local vascular dilatation in the pulp underneath the cavity. In addition, all teeth with deep unlined cavities showed inflammatory cells as did 1 with an intermediate depth unlined cavity. There were fewer displaced odontoblast nuclei in the dentin in the calcium hydroxide-treated groups. The milder reactions in the rubbed or covered groups are probably due to the restrictive effect by calcium hydroxide on penetration of amalgam components. In the teeth with deep cavities there were only minor differences between the ones which had been rubbed and those which had been covered with calcium hydroxide.

Calcium Hydroxide↗
PubMed1977

pH-stat titration of aluminum hydroxide gel.

The pH-stat titration of aluminum hydroxide gel was evaluated and was affected by pH, temperature, concentration, and ionic strength. Control of these parameters resulted in a highly sensitive and reproducible in vitro antacid test. The utility of the pH-stat test was illustrated by monitoring the aging of several carbonate-containing aluminum hydroxide gels and by comparing the antacid properties as measured by the pH-stat titration, the acid-consuming capacity, the Rossett-Rice test, and the test proposed by the food and Drug Administration Drug Evaluation Panel. The pH-stat titration also was useful for relatively nonreactive aluminum hydroxide gels. The use of sodium fluoride as the reaction medium extended the capability of the pH-stat titration to monitor the aging of chloride-containing gels. The pH-stat titrigram was interpreted in terms of a previously published polymer model of the structure of a chloride-containing aluminum hydroxide gel. The acid reactivity of relatively nonreactive gel is believed to be due totally to the chemical neutralization of acid, because the milliequivalents of aluminum ion appearing in solution is the same as the milliequivalents of acid neutralized throughout the ph-stat titration.

Adsorption↗
PubMed1976

Histopathologic evaluation of the effects of four calcium hydroxide liners on monkey pulps.

Pulpal response of four calcium hydroxide liners, MPC 10, MPC 12, Dycal and Pulpdent were tested on primary and permanent teeth with zinc oxide and eugenol (ZOE) and silicate as controls. Responses of the pulps were evaluatedi in Rhesus monkeys, utilizing Class V cavity preparations at 3 days, 5 and 8 weeks. An equivalent number of anterior and posterior teeth were studied for all compounds. The Ca(OH)2 liners, zinc oxide and eugenol (ZOE) and silicate controls were placed in 80 primary and 80 permanent teeth. Following perfusions the teeth were prepared utilizing routine histological procedures. The 3 day response of the calcium hydroxides was moderate with some disruption in the odontoblasts, vacuolization and mild inflammation underlying the cavity except Pulpdent which was more severe. At 5 weeks a decrease in inflammatory response and the formation of reparative dentin was similar for all calcium hydroxides tested at this time period. At 8 weeks more reparative dentin was noted with slight to moderate pulpal responses. At all time periods ZOE produced the least pulpal response while silicate produced the most severe response at 5 and 8 weeks. This study reports the biological responses of four calcium hydroxide compounds used as cavity liners in non-exposures in a series of primary and permanent teeth of monkeys using ZOE and silicate as controls. Responses to the four Ca(OH)2 compounds were moderate for all the experimental compounds except Pulpdent which was more severe at the early time period tested. ZOE produced a milder and silicate a severe response at all periods. All of these compounds were placed by random selection in anterior and posterior teeth of both arches and five teeth were evaluated in both primary and permanent teeth at 3 days, 5 and 8 weeks.

Animals↗
PubMed1977

Calcium hydroxide and potassium nitrate as desensitizing agents for hypersensitive root surfaces.

The purpose of this investigation was to evaluate calcium hydroxide and potassium nitrate individually as densensitizing agents for hypersensitive root surfaces. The apparatus used in the experiment to measure hypersensitivity was (a) a thermo-electric stimulating device to measure hot and cold stimulation quantitatively and (b) a mechanical stimulating device to measure scratch stimulation quantitatively. The conclusions drawn from the study were: 1. Calcium hydroxide was more consistently effective in decreasing sensitivity then was potassium nitrate or the control. 2. Calcium hydroxide as compared to the control was statistically (99% level of significance) more effective in reducing sensitivity to mechanical, hot and cold stimulation immediately and at the conclusion of the experiment (3 months). 3. It appears that calcium hydroxide could be used as a desensitizing agent initially following periodontal surgery to reduce pain from hypersensitive roots in order that proper oral hygiene could be reestablished.

Adult↗
PubMed1978

Aluminum hydroxide: evaluation of two dosage forms and two dosing schedules in reducing intestinal phosphate absorption.

A crossover, randomized, eight-week trial using eight adult volunteers was undertaken to (1) determine the efficacy of aluminum hydroxide in decreasing gastrointestinal phosphate absorption, (2) compare the effectiveness of "with meal" and "between meal" dosing schedules, and (3) compare the effectiveness of the capsule and liquid dosage forms. Four treatments, each with a daily dose of approximately 6 g, were taken on a three-times-a-day regimen. The effectiveness of the treatment regimens was measured by using two variables: the decrease in total urinary phosphorus excretion, and the increase in the percent tubular reabsorption of phosphorus (TRP). Aluminum hydroxide treatment produced a significant change in urinary phosphorus excretion (p less than 0.0005) and in percent TRP (p less than 0.0005). For the study population, total urinary phosphorus excretion was the determining factor in changing the percent TRP. The increase in TRP and the decrease in total urinary phosphorus excretion was of the same degree regardless of dosage form or dosage schedule. Aluminum hydroxide was effective in decreasing phosphorus absorption as measured in this study. It appears that aluminum hydroxide capsules could be used with equal efficacy as the liquid dosage form in controlling hyperphosphatemia in patients with chronic renal failure who will not comply with a treatment program using the liquid.

Adult↗