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Reduction of anthralin inflammation by potassium hydroxide and Teepol.

Application of 1% potassium hydroxide (KOH) reduced subsequent development of anthralin inflammation without loss of its therapeutic effect on psoriasis. Teepol had a similar but smaller effect on subsequent development of inflammation. The action of KOH appears to have resulted from enhanced oxidation of anthralin to inactive products and the action of Teepol to have increased anthralin solubility and removal. The effect of KOH and Teepol decreased with time after anthralin application and both were ineffective by 24 h, indicating that anthralin persists on the skin in an active form for up to 24 h after a single application. The reduction of anthralin inflammation without loss of therapeutic effect is potentially useful in short contact anthralin therapy.

Adolescent↗

Fruit acids and sodium hydroxide in the food industry and their combined effect with sodium lauryl sulphate: controlled in vivo tandem irritation study.

BACKGROUND: Cutaneous exposure to a variety of irritants has been extensively studied in recent years. Nevertheless, knowledge of the induction of irritant dermatitis, especially by mild irritants at low doses and for a short duration of exposure, is still incomplete. OBJECTIVES: To quantify the irritant effects and barrier disruption properties of ascorbic acid (ASC), acetic acid (ACA) and sodium hydroxide (NaOH), particularly in combination with an anionic detergent, sodium lauryl sulphate (SLS). METHODS: In a tandem repeated irritation test, the irritants were applied for 30 min twice daily for 4 days to the skin of the mid-back of 19 healthy volunteers of both sexes. We used bioengineering techniques for measurement of transepidermal water loss (TEWL) and skin colour reflectance, as well as visual scoring. RESULTS: Repeated application of ASC and ACA caused a moderate increase in TEWL and erythema. The sequential application of ASC or ACA and SLS enhanced these effects. NaOH induced a strong reaction when applied both occlusively and nonocclusively as well as in combination with SLS, with an early onset of the inflammatory signs, leading to discontinuation of the application on the third day in most of the test fields. Notably, the irritant effect of NaOH was not as marked when applied sequentially with SLS. CONCLUSIONS: Our results demonstrate that concurrent application of an anionic detergent and a mild acidic irritant can lead to disruption of the barrier function which, although not additive, is still considerable. The combined application of SLS and mild acids does not prevent SLS-induced irritation. Furthermore, we showed that NaOH in low concentrations may also act as a potent irritant but that its effect is not enhanced by SLS. The necessity of adequate skin protection and reduction of contact with substances that are potentially barrier disruptive and irritant, e.g. in the food industry, is emphasized, not only when handling detergents, but also when processing food products.

Acetic Acid↗

Aluminium hydroxide down-regulates T helper 2 responses by allergen-stimulated human peripheral blood mononuclear cells.

BACKGROUND: Aluminium hydroxide (alum) is a commonly used adjuvant for specific immunotherapy of allergic diseases. While alum is traditionally associated with murine Th2 sensitization, little is known about its effects on secondary allergic responses in humans. METHODS: We investigated the in vitro effects of alum on peripheral blood mononuclear cells (PBMC) from atopic donors. PBMC from 18 grass pollen-sensitive rhinitic subjects were stimulated with Phleum pratense (Phl p) in the presence or absence of alum. After 6 days culture, cytokine production was measured by ELISA and T cell proliferation by radiolabelled thymidine incorporation. The effect of alum on the expression of human leucocyte antigen and CD80/CD86 on cultured antigen-presenting cells was assessed by flow cytometry. RESULTS: PBMC cultured with Phl p and alum showed a significant decrease in both IL-5 and IL-13 production compared with allergen alone (P<0.005 and P<0.001, respectively), but no change in IFN-gamma or IL-12 production or proliferative responses. These alum-induced changes in T helper (Th)2 cytokine production were unaffected by the addition of neutralizing antibodies to IL-4 or IL-12. Culture of PBMC with alum induced increased expression of CD86 (P=0.004) and HLA (P=0.01) on monocytes while the expression of CD80 was decreased (P=0.02). SUMMARY: Alum down-regulates allergen-driven Th2 cytokine responses while Th1 cytokines are unaffected. These data confirm that alum is a useful adjuvant for inclusion in allergen immunotherapy vaccines.

Adjuvants, Immunologic↗

Review of calcium hydroxide.

Calcium hydroxide is a material which has been used for a variety of purposes since its introduction into dentistry in the early part of the twentieth century. In its pure form, the substance has a high pH, and its dental use relates chiefly to its ability to stimulate mineralization, and also to its antibacterial properties. A range of products has been formulated with different therapeutic actions, the effects of which are partially dependent upon the tissue to which they are applied. The material is reviewed under the following general headings: biochemical actions; dental formulation; uses.

Calcium Hydroxide↗

The antimicrobial effect of calcium hydroxide as a short-term intracanal dressing.

The antibacterial effect of calcium hydroxide as a short-term intracanal dressing was clinically evaluated by applying the medicament for 10 minutes or 7 days in root canals of teeth with periapical lesions. The results showed that the 7-day dressing efficiently eliminated bacteria which survived biomechanical instrumentation of the canal, while the 10-minute application was ineffective.

Bacteria, Anaerobic↗

Effects of extensive apical reaming and calcium hydroxide dressing on bacterial infection during treatment of apical periodontitis: a pilot study.

An apical dentine sampling technique was applied in order to monitor the bacteriology of the pulp canal and radicular dentine before and during treatment of teeth with chronic apical periodontitis. Twenty-three teeth with a radiographic diagnosis of apical periodontitis were studied. They were subjected to a standardized two-appointment treatment regimen of extensive apical reaming in the absence of antimicrobial agents and 1-week dressing with calcium hydroxide. Bacteriological samples were taken from the root canal at the start, and apical dentine samples at the end, of each sitting. Provision was made to allow growth of anaerobic bacteria. All root canals but one showed growth at the start of treatment. Dentine samples were positive in 14 of the 23 teeth at the end of the first appointment. Eight of the 23 canals had detectable growth from the canal at the start of the second appointment, but in sufficient numbers for quantification in only one root canal. The subsequent dentine samples were otherwise negative at the second appointment. There was a tendency for teeth causing symptoms to harbour more bacteria than symptomless teeth.

Adult↗

In vitro release of calcium and hydroxyl ions from two types of calcium hydroxide preparation.

Non-setting and setting pastes are the most common forms of calcium hydroxide, used in endodontics. The aim of this study was to investigate the differences in the availability of calcium and hydroxyl ions from some commercial preparations of both types. In vitro released calcium and hydroxyl ions were determined by a potentiometric method, after diffusion through sintered glass. The non-setting pastes evaluated were Calcipulpe, Calxyl Red, Calxyl Blue and Cinacal; while setting base materials were represented by Dycal, Nu-Cap and Reolit. The data obtained showed significantly higher availability of calcium and hydroxyl ions from non-setting pastes, compared with 'alkaline cements' (P < 0.05). Great variations in the amount of released ions were also found among samples of the same material.

Analysis of Variance↗

Calcium hydroxide paste in the maxillary sinus: a case report.

A case is reported in which a perforation of the sinus floor of the maxillary sinus occurred with extrusion of a calcium hydroxide paste during routine root canal treatment of a maxillary premolar. All clinical manifestations are described as well as the results of a follow-up evaluation.

Adult↗

The evaluation of removal of calcium hydroxide paste from an artificial standardized groove in the apical root canal using different irrigation methodologies.

AIM: To evaluate the capacity to remove a calcium hydroxide (Ca(OH)2) paste from the root canal and to evaluate the efficacy of Ca(OH)2 removal during passive ultrasonic irrigation using either sodium hypochlorite (NaOCl) or water as an irrigant. METHODOLOGY: Sixteen mandibular premolars were used. Each root was prepared to the apical foramen using GT instruments of size 30, 0.06 taper. Each root was split longitudinally. In one half of the root, a groove was cut in the canal wall 2-6 mm from the apex which was then filled with a Ca(OH)2 paste. Subsequently the roots were reassembled. In group 1 (n = 16), the teeth were ultrasonically irrigated using 50 mL 2.0% NaOCl as the irrigant. Group 2 (n = 16) was treated in the same manner as group 1, but using 50 mL water in place of the NaOCl. In group 3 (n = 16), the teeth were irrigated by syringe injection of 50 mL 2.0% NaOCl. The quantity of remaining Ca(OH)2 in the groove was scored and the data analysed with Kruskal-Wallis and Mann-Whitney tests. RESULTS: The difference in remaining Ca(OH)2 between all groups was statistically significant (P < 0.001). Group 1 had significantly lower scores than group 2 (P < 0.001) and group 3 (P = 0.002), but there was no significant difference between groups 2 and 3 (P = 0.765). CONCLUSIONS: Passive ultrasonic irrigation with 2% NaOCl was more effective in removing Ca(OH)2 paste from artificial root canal grooves than syringe delivery of 2% NaOCl or water as irrigant.

Calcium Hydroxide↗

The strength and fracture toughness of calcium hydroxide preparations.

The strength of a brittle material depends upon the toughness of the material itself and the degree of perfection with which it can be placed. This study shows that both the compressive and tensile strength of calcium hydroxide lining materials is dependent on the fracture toughness at unstable crack propagation, KIC, and the size, number and distribution of pores (which are the defects that nucleate fracture). Of the products tested here, Dycal possesses the greatest actual strength due to a higher than average KIC value and relatively few isolated small pores. However, the greatest potential for strength exists in Reocap which has a KIC value a factor of 2.4 greater than its nearest rival (Dycal). Unfortunately its strength, as determinedhere, is less than Dycal due to the large number of pores in close proximity to each other.

Calcium Hydroxide↗

Solubility of zinc oxide-eugenol and calcium hydroxide cements in simulated dentinal fluid.

The solubility of four dental cement bases was measured in simulated dentinal fluid and distilled water to evaluate the relevancy of the American Dental Association solubility test for cement bases in contact with vital dentine. A simulated dentinal fluid was formulated utilizing glucose, distilled water, and sterile human plasma. Cement-base samples were immersed in either distilled water or simulated dentinal fluid at 37 degrees C in a shaker water-bath for 1, 2, or 3 months. Weight loss values were compared utilizing a three-way analysis of variance. Zinc oxide-eugenol cements were significantly more soluble in simulated dentinal fluid than distilled water, while the calcium hydroxide cement bases were significantly more soluble in distilled water than simulated dentinal fluid.

Calcium Hydroxide↗

Microleakage of glass-ionomer cement placed in association with non-setting calcium hydroxide.

The purpose of this investigation was to determine whether non-setting calcium hydroxide [Ca (OH)2] cement placed in the root canal system of premolar teeth would affect the subsequent microleakage of a glass-ionomer restoration (GIC). Following selection, 62 human premolar teeth extracted for orthodontic reasons were accessed and root canals prepared according to a standardized procedure. The specimens were then allocated randomly into two major groups each of 30 teeth. Two other teeth were used as a positive and a negative control. The control group was restored with glass-ionomer cement following drying of the canal and placement of a cotton wool pledget. The test group had all canals dressed with non-setting Ca(OH)2 and then was subdivided, one set (n = 22) being restored following conditioning of the access cavity margins, the other (n = 8) having the margins cleaned with a hand excavator. Samples were assessed for microleakage using a two-point scoring system (leakage or no leakage) in conjunction with a clearing technique using AgNO3. Using Fisher's exact test, a statistically significant difference was found between the control and test groups (P < 0.05) but there was no significant difference between the excavated and conditioned cavities (P=0.55). It is concluded that contamination of access cavity margins with Ca(OH)2 during medication of a root canal interferes with the bond of GIC, resulting in increased microleakage in vitro.

Algorithms↗

Albert's solution versus potassium hydroxide solution in the diagnosis of tinea versicolor.

BACKGROUND: The diagnosis of tinea versicolor can usually be made by clinical examination. Either potassium hydroxide (KOH) or Wood's light fluorescence are used to corroborate the diagnosis. Albert's solution has been reported as a method of visualizing dermatophytes. We compared Albert's solution to KOH in the diagnostic evaluation of tinea versicolor. METHODS: Twenty patients with clinical tinea versicolor were examined for the presence of hyphae and/or spores utilizing Albert's solution or KOH (20%) with dimethyl sulfoxide. RESULTS: All patients were positive for hyphae and/or spores by both methods. Preparations with Alberts' stains were faster and easier to read. CONCLUSIONS: Albert's solution is an alternate method to stain for fungal elements in patients with tinea versicolor.

Acetates↗

Immunotherapy with yellow jacket venom. A comparative study including three different extracts, one adsorbed to aluminium hydroxide and two unmodified.

Thirty-two patients with previous systemic allergic reaction to yellow jacket stings were randomly allocated to three groups receiving immunotherapy with different preparations of yellow jacket venom: 1) extract adsorbed to aluminium hydroxide (Alutard-SQ), 2) Pharmalgen extract or 3) non-adsorbed extract from Allergologisk Laboratorium (ALK aq.). Regular examinations showed a decrease in skin prick test size in nearly all patients. Specific IgE-antibody (RAST and CRIE scores) showed a similar, but not significant tendency to decrease in all three groups. Specific IgG-antibody increased considerably in the Alutard group only; after 2 years, however, no difference could be detected between the three groups. During dose increase, patients treated with ALK aq. generally had smaller local reactions to injections than those treated with Pharmalgen. Few systemic reactions occurred in all three groups. Nineteen patients treated for 2 1/2-3 1/2 years were challenged in-hospital with stings from yellow jackets. No systemic and only minor local reactions occurred. Consequently, with the dose regimens applied all three extracts seem effective even though no common changes in either specific IgE or IgG could be demonstrated.

Adult↗

Latex allergen elimination in natural latex sap and latex gloves by treatment with alkaline potassium hydroxide solution.

Antigenic proteins in latex products can cause type I allergy. We investigated the effects of potassium hydroxide (KOH) solution on the allergenicity of proteins in natural latex sap and latex gloves by using an EAST competitive inhibition immunoassay and skin prick test. Latex sap was mixed with KOH solution at different concentrations and incubated over various periods of time at room temperature. Latex gloves were washed in KOH solution for different times at 30 degrees C and 90 degrees C. Our immunoassay results for the subsequently extracted latex proteins demonstrated a KOH concentration-, temperature-, and time-dependent decrease in allergenicity, finally resulting in complete loss of IgE-binding activity. In the skin prick test, we found only four weakly positive reactions to proteins extracted from KOH-washed gloves in 30 latex-sensitized patients. In addition, up to 97% of the aqueous extractable protein content could be removed from latex gloves by washing in KOH solution under certain conditions. These results suggest that antigenic proteins in natural latex sap and latex gloves can be changed by treatment with KOH solution, which is followed by a loss of their capability to bind specific IgE antibodies from most latex-sensitized patients.

Allergens↗

Magnesium-aluminum hydroxide suspension for the treatment of dermal capsaicin exposures.

OBJECTIVES: To determine whether magnesium-aluminum-hydroxide-simethicone suspension (MgAl) is an effective treatment for dermal capsaicin exposures. METHODS: The authors performed a double-blind, randomized, controlled, pilot study comparing the effect of MgAl with that of saline in the treatment of dermal capsaicin exposures. Ten volunteers were sprayed with a commercial defensive spray containing 10% capsaicin on the flexor surface of both forearms. A dressing embedded with MgAl (Maalox) suspension was randomly applied to one arm and a saline-embedded dressing was applied to the other arm. Pain was assessed on a 10-cm visual analog scale at 0, 10, 20, 30, 60, 90, and 120 minutes. RESULTS: Mean pain scores were significantly lower in the MgAl group as compared with the saline (S) group at 10, 20, and 30 minutes. Differences in pain scores were not statistically significant at times 60, 90, and 120 minutes. CONCLUSIONS: During the initial 30 minutes of treatment, there was a statistically significant decrease in pain scores with MgAl as compared with saline treatments. Although the difference in means may have questionable clinical significance, MgAl is cheap and readily available, and has minimal side effects. Thus, MgAl may be an appropriate treatment for dermal capsaicin exposure.

Administration, Cutaneous↗

Adjuvant effects of dimethyl dioctadecyl ammonium bromide, complete Freund's adjuvant and aluminium hydroxide on neutralizing antibody, antibody-isotype and delayed-type hypersensitivity responses to Semliki Forest virus in mice.

Outbred mice were inoculated subcutaneously with inactivated Semliki Forest virus (SFV) in saline and combinations of the virus with complete Freund's adjuvant (CFA) aluminium hydroxide (Al) and dimethyl dioctadecyl ammonium bromide (DDA). The immune response was evaluated for delayed-type hypersensitivity, for total ELISA antibodies and antibody-isotypes and for neutralizing antibodies. DDA was the most efficient adjuvant in inducing DTH, CFA the second and Al induced a DTH response that was only slightly higher (statistically not significant) than that induced by the inactivated virus without adjuvants. All adjuvants enhanced the production of ELISA antibodies to similar levels. However, the levels of neutralizing antibodies induced were low in mice which were inoculated with the inactivated SFV alone or mixtures of the virus with Al. DDA induced high levels of neutralizing antibodies and CFA induced intermediate levels. The pattern of antibody-isotypes induced by DDA and CFA was different from the pattern induced by the inactivated virus or by the virus mixed with Al: DDA and CFA induced low amounts of IgG1 antibodies and relatively higher amounts of IgG2a and IgG2b antibodies while the inactivated virus and the mixture of the virus with Al induced higher proportions of IgG1 antibodies. In sera from convalescent mice the majority of antibody activity resided in the IgG2a and IgG2b immunoglobulin subclasses, while IgG1 antibodies were undetectable.

Adjuvants, Immunologic↗