Home About us Contact
|
Home About us Contact | ||
|
|
||
Full Strength (full + strength)
Selected AbstractsLactic Acid Chemical Peels as a New Therapeutic Modality in Melasma in Comparison to Jessner's Solution Chemical PeelsDERMATOLOGIC SURGERY, Issue 12 2006KHALIFA E. SHARQUIE MBCHB BACKGROUND Many chemicals have been used in the skin peeling for melasma such as Jessner's solution and glycolic acid. Lactic acid is an ,-hydroxy acid that has not been used before in chemical peeling of melasma. OBJECTIVE The purpose of the present work was to evaluate the efficacy and safety of lactic acid in chemical peeling of melasma in comparison to Jessner's solution chemical peels. METHODS This study was conducted at the Department of Dermatology and Venereology, Baghdad Hospital, in the period between April 2001 and August 2002. Thirty patients with melasma were included in this study. They were mostly of skin type IV according to Fitzpatrick's classification, 26 (86.67%) were women, and 4 (13.33%) were men, with an age range from 18 and 50 years (mean±SD, 33.53±6.96 years). Full clinical examination was done to all patients including Wood's light. The severity of melasma was assessed by MASI (Melasma Area Severity Index). Pure lactic acid full strength (92%, pH 3.5) was used as a new peeling agent on the left side of the face while Jessner's solution was applied to the right side of the face. The chemical peeling sessions were done every 3 weeks until the desired response was achieved. Follow-up was carried out for 6 months after the last session. RESULTS Six patients were defaulted from the study after the first session for unknown reasons. Twenty-four patients completed the study. Twenty (83.33%) were women and four were men (16.67%). Wood's light examination showed increased contrast in all patients of mostly epidermal melasma. The number of sessions ranged from 2 to 5. All patients showed marked improvement as calculated by MASI score before and after treatment, and the response was highly statistically significant. No side effect was recorded in all treated patients. CONCLUSION Lactic acid was found to be an effective and safe peeling agent in the treatment of melasma, and it was as effective as Jessner's solution. [source] Effect of an essential oil-containing antiseptic mouthrinse on induction of platelet aggregation by oral bacteria in vitroJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 5 2000E. J. Whitaker Abstract Background: With an increasing body of data suggesting an association between periodontitis and cardiovascular disease, studies have been conducted to elucidate potential mechanisms by which oral bacteria might exert systemic effects. 2 oral bacteria, Streptococcus sanguis and Porphyromonas gingivalis, have been shown to induce platelet aggregation in vitro. This study was conducted to determine the effect of treatment with an essential oil mouthrinse (Listerine® Antiseptic) on the platelet-aggregating activity of these organisms. Method: Bacteria were grown under standard culture conditions. S. sanguis ATCC strain 10556 was exposed for 3 min to the essential oil mouthrinse at either full strength or a 1:1 dilution, while P. gingivalis FDC strain 381 was exposed to the essential oil mouthrinse at a 1:10 dilution. Positive control cells were treated with Hanks balanced salt solution (HBSS). Aggregation was measured using a recording platelet aggregometer. The assay of each organism in its respective mouthrinse dilution(s) or HBSS was repeated 5 times. Results: In all cases, the HBSS-treated organisms induced platelet aggregation, with mean(±S.E.) lag times of 12.30 (±1.36) min and 11.36 (±0.58) min for P. gingivalis and S. sanguis, respectively. In contrast, treatment with the essential oil mouthrinse completely inhibited the platelet aggregating activity of P. gingivalis and of S. sanguis exposed to the 1:1 mouthrinse dilution in all assays; the aggregating activity of S. sanguis treated with full-strength mouthrinse was completely inhibited in 4 of 5 assays, and inhibited by 75% in the 5th, for a mean inhibition of 95±1.5%. Conclusion: This study provides additional evidence that the essential oil mouthrinse can interfere with bacterial cell surface-associated activities which may have clinical relevance. [source] Novel application of oxygen-transferring membranes to improve anaerobic wastewater treatmentBIOTECHNOLOGY & BIOENGINEERING, Issue 4 2005Anthony S. Kappell Abstract Anaerobic biological wastewater treatment has numerous advantages over conventional aerobic processes; anaerobic biotechnologies, however, still have a reputation for low-quality effluents and operational instabilities. In this study, anaerobic bioreactors were augmented with an oxygen-transferring membrane to improve treatment performance. Two anaerobic bioreactors were fed a synthetic high-strength wastewater (chemical oxygen demand, or COD, of 11,000 mg l,1) and concurrently operated until biomass concentrations and effluent quality stabilized. Membrane aeration was then initiated in one of these bioreactors, leading to substantially improved COD removal efficiency (>95%) compared to the unaerated control bioreactor (,65%). The membrane-augmented anaerobic bioreactor required substantially less base addition to maintain circumneutral pH and exhibited 75% lower volatile fatty acid concentrations compared to the unaerated control bioreactor. The membrane-aerated bioreactor, however, failed to improve nitrogenous removal efficiency and produced 80% less biogas than the control bioreactor. A third membrane-augmented anaerobic bioreactor was operated to investigate the impact of start-up procedure on nitrogenous pollutant removal. In this bioreactor, excellent COD (>90%) and nitrogenous (>95%) pollutant removal efficiencies were observed at an intermediate COD concentration (5,500 mg l,1). Once the organic content of the influent wastewater was increased to full strength (COD = 11,000 mg l,1), however, nitrogenous pollutant removal stopped. This research demonstrates that partial aeration of anaerobic bioreactors using oxygen-transferring membranes is a novel approach to improve treatment performance. Additional research, however, is needed to optimize membrane surface area versus the organic loading rate to achieve the desired effluent quality. © 2005 Wiley Periodicals, Inc. [source] The Chemistry of Escapin: Identification and Quantification of the Components in the Complex Mixture Generated by an L -Amino Acid Oxidase in the Defensive Secretion of the Sea Snail Aplysia californicaCHEMISTRY - A EUROPEAN JOURNAL, Issue 7 2009Michiya Kamio Dr. Abstract A complex mixture of products in an enzymatic reaction: Aplysia californica releases amino acid oxidase and its substrate lysine in defensive secretions to produce a mixture of multiple compounds (see figure). Escapin is an L -amino acid oxidase in the ink of a marine snail, the sea hare Aplysia californica, which oxidizes L -lysine (1) to produce a mixture of chemicals which is antipredatory and antimicrobial. The goal of our study was to determine the identity and relative abundance of the constituents of this mixture, using molecules generated enzymatically with escapin and also using products of organic syntheses. We examined this mixture under the natural range of pH values for ink,from ,5 at full strength to ,8 when fully diluted in sea water. The enzymatic reaction likely forms an equilibrium mixture containing the linear form ,-keto-,-aminocaproic acid (2), the cyclic imine ,1 -piperidine-2-carboxylic acid (3), the cyclic enamine ,2 -piperidine-2-carboxylic acid (4), possibly the linear enol 6-amino-2-hydroxy-hex-2-enoic acid (7), the ,-dihydroxy acid 6-amino-2,2-dihydroxy-hexanoic acid (8), and the cyclic aminol 2-hydroxy-piperidine-2-carboxylic acid (9). Using NMR and mass spectroscopy, we show that 3 is the major component of this enzymatic product at any pH, but at more basic conditions, the equilibrium shifts to produce relatively more 4, and at acidic conditions, the equilibrium shifts to produce relatively more 2, 7, and/or 9. Studies of escapin's enzyme kinetics demonstrate that because of the high concentrations of escapin and L -lysine in the ink secretion, millimolar concentrations of 3, H2O2, and ammonia are produced, and also lower concentrations of 2, 4, 7, and 9 as a result. We also show that reactions of this mixture with H2O2 produce ,-aminovaleric acid (5) and ,-valerolactam (6), with 6 being the dominant component under the naturally acidic conditions of ink. Thus, the product of escapin's action on L -lysine contains an equilibrium mixture that is more complex than previously known for any L -amino acid oxidase. [source] | ||||||||||