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Liver Diseases
Published in George Feuer, Felix A. de la Iglesia, Molecular Biochemistry of Human Disease, 2020
George Feuer, Felix A. de la Iglesia
Experimental evidence shows the effect of riboflavin deficiency on skin tumors.356 Pyridoxine deficiency occurs in alcoholics, probably attributable to the formation of acetaldehyde; pyridoxine derivatives enhance the destruction of this compound.373 Pyridoxine deficiency is connected with increased formation of liver cancer.605 In addition to the key role of vitamin B6 in hematopoiesis, it also participates in the antibody response to various antigens,19 thus indirectly modifying the development of various tumors. In alcoholics, blood levels of vitamin E are very low.368,416 Vitamin E and other antioxidants, such as butylated hydroxy toluene and propyl gallate, reduce the incidence of tumors induced by certain carcinogens.563,584
Allergic Contact Dermatitis to Ingredients other than the Active Drug
Published in Anton C. de Groot, Monographs in Contact Allergy, 2021
During the preparation of the monographs in Chapter 3 and by searching in the first 2 volumes of the Monographs in Contact Allergy series (1,2), the author found 149 non-drugs chemicals, that have caused contact allergy/allergic contact dermatitis by their presence in topical drugs: 46 vehicle ingredients, 35 preservatives and antioxidants, 44 fragrances and essential oils and 24 other chemicals (tables 4.3–4.6). Some additional haptens, not present there, may be found in tables 4.1 and 4.2. In the category vehicle ingredients, the most frequently implicated chemicals were propylene glycol, followed by lanolin (alcohol) and cetyl and stearyl alcohol. Among the preservatives and antioxidants, thimerosal and benzalkonium chloride caused many cases of sensitization, especially from their presence in eye drops. Frequent reactions have also been noted to sodium metabisulfite and benzyl alcohol, followed by propyl gallate, chlorocresol and the parabens, the latter often in older publications from their presence in corticosteroids and antibiotic preparations. Fragrances and essential oils are not frequently implicated, although lavender essence/oil has caused several cases of (photo)allergic contact dermatitis from its presence in ketoprofen gel (4,41,42). Of the other chemicals, only alcohol in estradiol transdermal therapeutic system and colophonium (notably in wart treatments) have caused several cases, and ethylenediamine in Mycolog® cream many cases of allergic contact dermatitis. The other ingredients, some of which cannot properly be identified on the base of their names as provided in the original publications, mostly caused single reactions only. However, the actual nature of the non-drug constituents in topical pharmaceuticals, and their (absolute and relative) frequencies remain largely unknown, as only a very small minority of all patients reacting to a topical drug will be patch tested with all its constituents. Testing bias (haptens present or not in the routine series or additional test series) and publication bias (well-known allergens are not published) further complicate this issue.
Immunocytochemical Detection Systems
Published in Lars-Inge Larsson, Immunocytochemistry: Theory and Practice, 2020
Several attempts have been made to combat the fading phenomenon, particularly with FITC. Normally, sections are mounted in a mixture of glycerin and phosphate or Tris buffer, pH 7.0 to 7.4. Fading is somewhat retarded by mounting at higher pH (8.6) or by mounting in nonfluorescent, xylene-miscible media such as Entellan.®81,243 Lennette suggested use of polyvinyl alcohol (PVA), buffered to pH 9, to store FITC-stained specimens.190 Reduction of the fading of FITC and rhodamine was obtained with (1) n-propyl gallate,107 (2) 1 mg/mℓ paraphenylenediamine (PPD) in glycerin,161 (3) 1 mg/mℓ 1,4-diazobicyclo- (2,2,2)-octane (DABCO) in gelvatol,183 or (4) 25 mg/mℓ DABCO in phosphate-buffered glycerin.162 The advantage with DABCO was the finding that, in contrast to other mounting media, its addition did not destroy the specimens upon storage.183 A comparison was more recently made by Valnes and Brandtzaeg, who recommended use of polyvinyl alcohol medium containing 0.2 to 2 g/ℓ of PPD or 6 g/ℓ of n-propyl gallate.354 These authors found no advantage with DABCO, except that it permitted long-term storage. There are several considerations in the use of these mounting media (effects on TRITC contra FITC, effects on section durability, effects on tissue background fluorescence). We have never used them, but have relied upon inspection of freshly stained sections mounted in glycerine:buffer (9:1). The interested reader should consult the original publications before embarking on this avenue for prolonging fluorescent life. Conceivably, the methods could be extremely helpful for preventing fading of weakly fluorescent structures during photography. Upon storage of conventionally mounted immunofluorescence preparations, fluorescence is gradually lost. Weinstein and Lechago observed that fluorescence in indirect immunofluorescence-stained preparations (as well as in sections poststained with hematoxylin-eosin) could be regained by renewed application of the FITC-labeled second antibody.374 Conceivably, this could indicate loss of fluorescence due to dislodgement of the fluorochromed second antibodies during storage, but this question was never addressed. Nevertheless, we have repeatedly used the Weinstein and Lechago approach also on semithin plastic sections that have faded in the fluorescence microscope (Larsson, unpublished data) and have found it to work very well.
Plasma uptake of selected phenolic acids following New Zealand blackcurrant extract supplementation in humans
Published in Journal of Dietary Supplements, 2022
Rianne Costello, Karen M. Keane, Ben J. Lee, Mark E. T. Willems, Stephen D. Myers, Fiona Myers, Nathan A. Lewis, Sam D. Blacker
A method previously described (Keane at al., 2016) was used for the extraction of phenolic compounds from the plasma. Briefly, 1mL of plasma and 0.5mL of propyl gallate (internal standard, 50µg, 100µL/mL) was mixed with 4mL oxalic acid (10nM) and 0.1mL hydrochloric acid (HCl; 12.6M) in 15mL falcon tubes and centrifuged at 3000rpm for 15min. The supernatant was absorbed on to a primed (washed with 5mL methanol (MeOH) with 0.2% trifluoroacetic acid (TFA) followed by 2×5mL of water) solid-phase extraction cartridge (Waters Sep-Pak c17, 360mg sorbent per cartridge, 55-105µm). The sample was eluted with 3mL of MeOH + 0.2% TFA and dried under N2 at 45°C. Samples were then reconstituted in 400µl of 0.1% formic acid in water: 2% HCl in MeOH (1:1) and filtered through a 0.2µm polytetrafluoroethylene filter before HPLC analysis. Samples were analyzed on a batch basis, where each batch included standards prepared in 0.1% formic acid in water: 2% HCl in MeOH (1:1), blank control, plasma samples, and fortified plasma samples at 1 (low), 10 (medium), and 25 (high) µg/mL. The recovery ranges were 89-95%, 89-102%, and 90-103% for low, medium, and high fortified levels, respectively. The final results were collected for recovery at the low fortification level.
Nutritional supplementation of gallic acid ameliorates Alzheimer-type hippocampal neurodegeneration and cognitive impairment induced by aluminum chloride exposure in adult Wistar rats
Published in Drug and Chemical Toxicology, 2022
B. Ogunlade, S. A. Adelakun, J. A. Agie
GA and its derivatives such as lauryl gallate, propyl gallate, octyl gallate, tetradecyl gallate have the potential of inhibiting the oxidation and rancidity of oils and fats being attributed to their antioxidant and free radical scavenging ability (Choubey et al.2015). Several scientific reports on the biological and pharmacological activities of GA revealed its antioxidant, (Aruoma et al.1993, Nabavi et al.2012, Ferk et al.2018), antimicrobial, anti-inflammatory, (Lo et al.2010). anticarcinogenic, (Jagan et al.2008, You and Park 2010, Mileo and Miccadei 2016, Velderrain-Rodríguez et al.2018). cardioprotective, (Umadevi et al.2012, Badhani et al.2015) gastroprotective, (Ihara et al.1999, Ajiboye et al.2018) and neuroprotective potential (Choubey et al.2015, Hajipour et al.2016). Therefore the present study aimed to explore the antioxidant, neuroprotective and anti-inflammatory potential of GA on the brain (hippocampus) against aluminum chloride induced Alzheimer’s type of neurodegenerative disorder in adult Wistar rats.
Anti-aging formulation of rosmarinic acid-loaded ethosomes and liposomes
Published in Journal of Microencapsulation, 2019
Çiğdem Yücel, Gökçe Şeker Karatoprak, İsmail Tuncer Değim
Rosmarinic acid (RA) is a compound can be found in plants from the Lamiaceae family formed by caffeic acid and 3,4-dihydroxyphenylacetic acid esterification. It was first isolated from Rosemary (Rosmarinus officinalis) plant and later on many species belonging to this family determined to have RA (Fadel et al.2011). RA is widely used as an antioxidant by acting as free radical scavenger and is effective in preventing the formation of lipid peroxides, which is caused by UV rays and physical, and chemical external factors in the cosmetic field. Studies have shown that RA has more antioxidant activity than the other antioxidant compounds such as vitamin E and trolox which is vitamin E analogue (Lin et al. 2002, Shekarchi et al.2012). RA is more preferable natural compound acting free radical scavenger in the cosmetic field. It does not cause any toxicity which may be caused by synthetic antioxidants such as butyl hydroxy toluene (BHT), butyl hydroxy anisole (BHA), and propyl gallate (Tırnaksız 2006, Shekarchi et al.2012).