Manufacturing and standardizing allergen extracts in Europe
Richard F. Lockey, Dennis K. Ledford in Allergens and Allergen Immunotherapy, 2020
Physical modification of allergens involves adsorption of the allergen extract with insoluble complexes of inorganic salts, such as aluminum hydroxide or calcium phosphate. Aluminum hydroxide, Al(OH)3, is especially useful for vaccination purposes and is used in both human and veterinary medicine [22]. Its advantages are based on two characteristics of the complexes, the depot effect and the adjuvant effect. The allergens bind firmly to the inorganic complexes, giving rise to slow release of the proteins, thereby lowering the concentration of allergen in the tissue and reducing the risk of systemic side effects. Furthermore, the depot effect reduces the number of injections needed in the course of specific allergy vaccination. Although the significance of the adjuvant effect is unclear, higher levels of IgG antibodies are observed when alum-adsorbed vaccines are used in specific allergy vaccination, as compared to aqueous vaccine [23]. Compared to aqueous vaccines, patients receiving depot preparations seem to experience fewer systemic side effects [24], particularly severe early reactions. The frequency of late reactions, which seem to be milder and can be managed by the patient at home, are reduced to a lesser extent, especially in asthmatic patients [25].
Manufacturing and Standardizing Allergen Extracts in Europe
Richard F. Lockey, Dennis K. Ledford in Allergens and Allergen Immunotherapy, 2014
Physical modification of allergens involves adsorption of the allergen extract with insoluble complexes of inorganic salts, such as aluminum hydroxide or calcium phosphate. Aluminum hydroxide, Al(OH)3, is especially useful for vaccination purposes and is used in both human and veterinary medicine [15]. Its advantages are based on two characteristics of the complexes, the depot effect, and the adjuvant effect. The allergens bind firmly to the inorganic complexes, giving rise to a slow release of the proteins, thereby lowering the concentration of the allergen in the tissue and reducing the risk of systemic side effects. Furthermore, the depot effect reduces the number of injections needed in the course of specific allergy vaccination. Although the significance of the adjuvant effect is unclear, higher levels of IgG antibodies are observed when alum-adsorbed vaccines are used in specific allergy vaccination, as compared to aqueous vaccine [16]. Compared to aqueous vaccines, patients receiving depot preparations seem to experience fewer systemic side effects [17], particularly severe early reactions. The frequency of late reactions, which seem to be milder and can be managed by the patient at home, are reduced to a lesser extent, especially in asthmatic patients [18].
Writing Chemical Equations
Patrick E. McMahon, Rosemary F. McMahon, Bohdan B. Khomtchouk in Survival Guide to General Chemistry, 2019
Write balanced equations based on the following descriptions: Sulfur dioxide gas reacts with oxygen gas to form sulfur trioxide gas.Calcium oxide solid plus water forms calcium hydroxide solid.Calcium carbonate solid decomposes to form calcium oxide solid plus carbon dioxide gas.Chromium (II) oxide solid is converted to chromium metal plus oxygen gas.Cobalt (II) nitrate in an aqueous solution plus sodium phosphate in an aqueous solution forms cobalt (II) phosphate solid plus sodium nitrate in an aqueous solution.Gold (III) chloride solid reacts with iron metal to form gold metal plus iron (III) chloride solid.Aluminum hydroxide solid decomposes to form aluminum oxide solid plus water.Lead (II) acetate in an aqueous solution reacts with potassium sulfate in an aqueous solution to form lead (II) sulfate solid plus potassium acetate in an aqueous solution.
Ultrahigh verapamil-loaded controlled release polymeric beads using superamphiphobic substrate: D-optimal statistical design, in vitro and in vivo performance
Published in Drug Delivery, 2018
Carol Yousry, Maha M. Amin, Ahmed H. Elshafeey, Omaima N. El Gazayerly
In our work, superamphiphobic surfaces were prepared using aluminum substrates. The hot ammonia solution was used to chemically etch the surface thus creating the required rough hierarchical structure. The ammonia solution generated (OH)− group that reacted with Al3+ ions to produce triangular clusters of aluminium hydroxide and aluminium hydroxide oxide (Peng & Deng, 2015). Then, the rough surface was immersed in alcoholic solution of PFDTS to derive the surface with Difluoromethane and trifluoromethane tails and thus, lower the surface free energy. PFDTS was chosen because of its chemical stability and its ability to interact with the surface under mild conditions (Deng et al., 2017). Figure 1(A) presents the SEM images of the substrate that show aggregates of triangular prisms in the micro-size range. Upon magnification, fine protrusions appear on the surface of such prisms that create the rough nano-micro hierarchical structure required to trap a large amount of air at the solid-liquid interface to prevent the penetration of oils and water into the grooves and control the surface wettability.
Exploring research gaps and trends in the management of acute phosphide poisoning: a systematic review
Published in Critical Reviews in Toxicology, 2023
Zahraa Khalifa Sobh, Marwa Kholief, Eman Khalifa Sobh, Manal Ibrahim Fathy Balah
Aluminum phosphide is a highly toxic compound (oral LD50: 11.5 mg/kg), that is used as a fumigant, insecticide, and rodenticide (Bingham et al. 2001). AlP is commonly available as tablets, therefore, it is described as “rice tablets” or “wheat bills” (trade names: Quickphos, Phostoxin, Bhostoxin, Phostek, Phosphume). Each rice tablet is three grams and is constituted of 56% AlP and 44% aluminum carbonate and releases one gram of PH3 upon exposure to moisture. The AlP tablet is often grayish; however, it could be green or brown. AlP is also available as pellets (trade names: Quickphos, Alphos, Cellphos). Each 0.6 g pellet releases 0.2 grams of PH3 gas upon exposure to humidity. After the release of PH3 gas from AlP formulas, nontoxic aluminum hydroxide residues are left behind (Moghadamnia 2012). The fatal dose of AlP for a 70 kg adult is 150–500 mg for oral intake. Regarding inhalational exposure, the permissible exposure limit (PET) of AlP is 0.3 ppm throughout an 8-h shift. The short-term exposure limit (STEL) is one ppm, and the immediate threat to life and health is 200 ppm. The 400–600 ppm range has been identified for the deadly dose in 30 min (Environmental Protection Agency 1998; Bingham et al. 2001).
Preclinical developments in the delivery of protein antigens for vaccination
Published in Expert Opinion on Drug Delivery, 2023
Dylan A. Hendy, Alex Haven, Eric M. Bachelder, Kristy M. Ainslie
Aluminum hydroxide (alum) is one adjuvant that is widely used with subunit vaccines. One example of a current clinical subunit vaccine that includes alum is the anthrax vaccine adsorbed (AVA) which is produced under the name BioThrax® (Emergent BioDefense Corporation) and first licensed for human use in 1970 [25]. AVA contains the anthrax protective antigen (PA) protein and is adjuvanted with alum. Alum containing adjuvants were first found to be immunostimulatory in 1926 and since then they have been used in various vaccines such as diphtheria, pertussis, and tetanus [26]. Broadly, alum covers multiple similar adjuvants and can include aluminum salts such as aluminum hydroxide, aluminum phosphate, and aluminum potassium sulfate. Although the exact mechanism of alum is still in contention, it is thought that these adjuvants promote immunogenicity by adsorbing antigens as well as causing local inflammation at the site of injection resulting in activation of the NLR family pyrin domain containing 3 (NLR3) inflammasome [27,28]. This in turn promotes a strong Th2 response with high levels of neutralizing antibodies; however, alum only very weakly activates a Th1 response. Furthermore, while AVA is effective in producing neutralizing antibodies against PA the protection is extremely inefficient requiring 5 doses followed by boosters every 12–18 months [29].
Related Knowledge Centers
- Acid
- Aluminium Oxide
- Aluminium Phosphate
- Calcination
- Magnesium Hydroxide
- Amphoterism
- Brønsted–Lowry Acid–Base Theory
- Lewis Acids & Bases
- Bayer Process
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