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The Augmentation of Tumor-Specific Immunity In Vitro and In Vivo with Immune RNA*
Published in Edward P. Cohen, A. Arthur Gottlieb, Immune RNA, 2020
Peter J. Deckers, Bosco S. Wang, John A. Mannick
For RNA extraction, homogenization of the guinea pig lymphoid tissues was performed in a Sorvall® omnimixer* containing phenol which had been washed three times with a 0.01 M sodium acetate buffer containing 0.1% 8-hydroxy-quinolone** and an equal volume of 0.01 M acetate buffer pH 5.0 containing 0.1% sodium dodecyl sulfate and 2 mg/ml of polyvinyl sulfuric acid potassium salt.*** Ten drops of bentonite solution† (11.4 mg/ml) was also added to this mixture. Lymphoid tissues were homogenized at 4° C for 3 min, transferred to a 40-ml centrifuge tube, and heated to 50° C in a water bath with constant stirring. The mixture was then immediately cooled to 4° C in an ice bucket containing alcohol and dry ice and centrifuged at 28,000 × g at 4° C for 10 min. The aqueous phase containing the RNA was carefully removed with a pipette. An equal amount of buffer-washed phenol was added to the aqueous phase and the extraction procedure repeated three times. After the last extraction, the aqueous phase was adjusted to 0.3 M with 2.4 M acetate buffer and the RNA precipitated with absolute ethanol. The precipitate was collected by centrifugation at 1,400 × g at 4° C for 5 min and washed twice in 30 ml of 75% ethyl alcohol. The pellet was then dissolved in Hanks’ solution without phenol red. The RNA preparations used had an OD:260-to-OD:280 ratio of 2.0 or greater in a Beckman DU® spectrophotometer.
Nail Product Rheology
Published in Laba Dennis, Rheological Proper ties of Cosmetics and Toiletries, 2017
The nomenclature for clays as used today is somewhat fuzzy, with conflicts among manufacturers' literature, patents, and dictionaries. Most manufacturers use the terminology presented in Table 5. This chapter uses the terms consistently according to Table 5, but the use cannot be guaranteed when quoting from other sources. The terms montmorillonite and bentonite are particularly confusing, especially in the cosmetics industry, for which the CFTA dictionary (35,36) names some ingredients hectorites and others bentonites (instead of montmorillonites). In general, bentonite is the rock containing the clays of interest. Smectites are the mineral group of clays characterized by swelling and high cation-exchange properties. Montmorillonites and hectorites are specific clays in the smectite group.
Miscellaneous pesticides*
Published in Bev-Lorraine True, Robert H. Dreisbach, Dreisbach’s HANDBOOK of POISONING, 2001
Bev-Lorraine True, Robert H. Dreisbach
Give activated charcoal (see pp. 31–32)followed by gastric lavage with repeated 200-ml volumes of 1% bentonite solution (1 part of bentonite magma diluted with four parts of water). The administration of bentonite should be repeated twice daily for the first 48 h. The addition of a saline cathartic to bentonite is also useful. If bentonite is not available, activated charcoal should be given.
Nasal residence time and rheological properties of a new bentonite-based thixotropic gel emulsion nasal spray – AM-301
Published in Drug Development and Industrial Pharmacy, 2023
Martin M. Sailer, Melanie Köllmer, Beatrice Masson, Fabio Fais, Ilja P. Hohenfeld, Michael E. Herbig, Assen K. Koitschev, Sven Becker
Many intranasal formulations show a clearance half-life of about 15 min [17]. An important requirement for an effective nasal administration is nasal residence time which may be increased by two different methods: (i) mucoadhesion; (ii) viscosity enhancers. Mucoadhesion requires the addition of polymers to the formulation to alter the viscosity, rheology and ciliary beating frequency. The second approach involves the use of viscosity enhancers to alter the intrinsic physical properties of the formulation without impairing the ciliary beating frequency and the physiological features of the nasal environment [18,19]. In particular, in vitro cytotoxicity assays performed in one of our previous studies showed that AM-301 slightly reduces the ciliary beating frequency (by about 1 Hz) when applied on human nasal epithelial inserts. However, this effect seems to be due to the viscosity of the preparation rather than to the bentonite per se [15]. AM-301 has been prepared following this approach and contains only excipients and inert ingredients listed in the Inactive Ingredient Database of the US Food and Drug Administration (FDA), ‘generally recognized as safe’ or approved as food additives [20].
First report on the presence of aflatoxins in fig seed oil and the efficacy of adsorbents in reducing aflatoxin levels in aqueous and oily media
Published in Toxin Reviews, 2022
Bentonite is another effective agent in reducing aflatoxin levels in aqueous dried fig extracts (Figure 1). Treating with this agent resulted in minimum 89% reductions in levels of both aflatoxin B1 and total aflatoxins in aqueous dried fig extracts. Aflatoxin reduction rates obtained with bentonite and activated carbon treatments were not significantly different in most cases (p > 0.05). Similarly, Diaz et al. (2003) and Fernandes et al. (2019) indicated that both bentonite and activated carbon were quite effective in aflatoxin removal from model systems yielding close reduction rates. Bentonite, a naturally occurring clay, has a layered structure which mainly consists of montmorillonite (Senturk et al. 2009). It was reported that this clay was effective in reducing aflatoxin M1 levels in milk (Carraro et al. 2014) and aflatoxin B1 levels in model systems (Tabari et al.2018). Wang et al. (2020) claimed that bentonite has active sites within its interlamellar region for aflatoxin sorption. According to the authors, the carbonyl moiety in the aflatoxin molecule is important for binding. On the other hand, Phillips et al. (2019) claimed that other mechanisms such as electron donor acceptor complexation, ion-dipole interaction, and coordination between exhange cations and the carbonyl oxygens can also lead to the aflatoxin binding. It was shown that the adsorption strength of bentonite strongly depends on its mineral content (Galvano et al.2001) and the pH of the media (Bueno et al.2005).
Organomodified nanoclays induce less inflammation, acute phase response, and genotoxicity than pristine nanoclays in mice lungs
Published in Nanotoxicology, 2020
Emilio Di Ianni, Peter Møller, Alicja Mortensen, Józef Szarek, Per Axel Clausen, Anne Thoustrup Saber, Ulla Vogel, Nicklas Raun Jacobsen
Clay minerals have long been used in composite materials to improve physical and mechanical properties (Patel et al. 2006). Bentonite is the commercial name of montmorillonite, a member of the Smectite clay family (swelling clays), and contains an octahedral alumina or magnesia sheet between two tetrahedral silica sheets (Jensen et al. 2009). Its chemical functionalization is obtained by substituting the interlayer cations with surface modifiers such as quaternary ammonium compounds (QAC), including benzalkonium chloride (BAC), which generate organomodified clays (ONC). These are amphiphilic and facilitate dispersion of ONC into the composite polymer materials (Carretero, Gomes, and Tateo 2006; Jensen et al. 2009; Stueckle et al. 2018).