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Contraceptive Intervention
Published in Sujoy K. Guba, Bioengineering in Reproductive Medicine, 2020
SMA is an alternate co-polymer of maleic anhydride and styrene (Figure 5.4). When SMA comes in contact with water molecules of spermatic fluid, the acid anhydride component is hydrolyzed. Following hydrolysis, the carboxyl group exerts an effect like acids, but only on material in the immediate vicinity of the polymer. A phenomena analogous to the suspension effect results.16 In the presence of a buffer, an equilibrium state between the swollen polyelectrolyte, in this case the SMA, and its surrounding is set up and, in effect, an equivalent of Donnan membrane equilibrium exists. There is therefore no neutralization effect as occurs for ordinary acidic materials and there is no loss of positive hydrogen ions. Viewed in another manner, an equilibrium between mobile ions and counter ions is established so as to have a charge effect but no osmotic effect. In the vas deferens, as in other body tissue, there are naturally occurring buffer fluids. Although there is continuous replenishment of the buffer at any particular time, the quantity of buffer present in the small space remaining between the polymer when injected into the lumen of the vas deferens, spermatozoa, and lumen wall of the vas deferens is small. Thus, the pH lowering action can theoretically be expected to prevail over the buffering effect of the fluids. Linkage with the styrene group prevents dissolution of the acid anhydride even after hydrolysis and thereby gives long-term stability. Spermatozoa passing near the polymer are subjected to low pH (5.0 — 6.0) and the acrosomal membrane integrity is destroyed (Figures 5.5a, b, and c).
Epidemiology and research
Published in Greta Thornbory, Susanna Everton, Contemporary Occupational Health Nursing, 2017
Nielsen et al.37 did a prospective study lasting 8.5 years on newly employed Swedish workers exposed to organic acid anhydrides (OAA) in three different factories. These substances are used as hardeners in epoxy resin systems and are powerful sensitisers, giving frequent rhinitis and asthma in exposed workers. The different factories used the OAA for the production of barrels for grenade firearms, to fix and isolate components in ignition systems and in the production of capacitors.
Occupational Asthma
Published in Jonathan A. Bernstein, Mark L. Levy, Clinical Asthma, 2014
HMW and LMW agents known to cause OA involve T-helper type 2 (Th2) proinflammatory cytokines characteristic of IgE-mediated allergic asthma.19 Enzymes are a good example of HMW agents whereas acid anhydrides are a good example of LMW agents known to cause OA through an IgE-mediated mechanism. In contrast to HMW agents, most LMW chemicals (plicatic acid and diisocyanates) cause OA through as of yet unknown non-IgE-mediated mechanisms. Several mechanisms have been proposed for different clinical presentations associated with a number of causative agents.19 For acid anhydrides, specific IgE, cytotoxic, immune complex, and cell-mediated immune responses have all been reported (Table 24.1).25,26 The mechanism(s) for irritant-induced asthma or RADS caused by a single high exposure or chronic low exposure to a chemical (i.e., anhydrous ammonia) also remains elusive.4 It is speculated that chronic inflammatory changes occur in these workers as a result of toxic injury to bronchial epithelial cells leading to loss of epithelial-derived relaxing factors combined with neurogenic inflammation and release of bioactive mediators and proinflammatory cytokines by nonspecific activation of mast cells.4 A number of OA animal models have been developed in an attempt to better elucidate the role of innate and adaptive immune responses in causing a variety of IgE and non-IgE-mediated induced OA.27–29
Alveolar hemorrhage due to marijuana smoking using water pipe made with plastic bottle: case report and narrative review of the literature
Published in Inhalation Toxicology, 2021
Ségolène Toquet, Joël Cousson, Nathalie Choiselle, Claire Gozalo, Delphine Giusti, Firouze Bani-Sadr, Yohan N’Guyen
The main explanation suggested by Grassin and the authors of these cases (Klotz and Martin 2009; Grassin et al. 2011; Moatemri et al. 2016; Caviedes et al. 2019), almost all described before the e-cigarette, or vaping, product use-associated lung injury (EVALI) epidemics, was the potential concomitant inhalation of acid anhydrides derived from heated plastic bottle. This was suggested by the implication of acid anhydrides, such as phtalic anhydride or trimellitic anhydrides (TMA) in two former occupational diseases associated with resins or plastics vapors, namely ‘meat’s wrapper asthma’ and ‘pulmonary disease- anemia syndrome’ (Herbert and Orford 1979; Zeiss et al. 1988; Venables 1989; Kaplan et al. 1993). AH could occur in ‘pulmonary disease- anemia syndrome’ but not in meat’s wrapper asthma. ‘Meat’s wrapper’ asthma is immune mediated and more frequently due to phtalic anhydride, whereas ‘pulmonary disease- anemia syndrome’ is due to TMA and either toxic or immune mediated (Zeiss et al. 1988; Venables 1989). Indeed, specific antibodies against TMA were inconsistently detected in serum of workers exposed to epoxy resin vapors (Herbert and Orford 1979; Kaplan et al. 1993), but they appeared correlated with the number of hemorragic foci in lungs of Sprague Dawley rats (Zeiss et al. 1988). Lastly, a case very similar to ‘pulmonary disease- anemia syndrome’ had been described without any professional exposure but after smoking marijuana adulterated with benzene (Mémain et al. 2001). We therefore tried to confirm the role of acid anhydrides in our case using available means.
Synthesis and biological evaluation of benzothiazin-4-ones: a possible new class of acetylcholinesterase inhibitors
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2019
Gabriele A. Berwaldt, Daniela P. Gouvêa, Daniel S. da Silva, Adriana M. das Neves, Mayara S. P. Soares, Juliana H. Azambuja, Geonir M. Siqueira, Roselia M. Spanevello, Wilson Cunico
Benzothiazinones derivatives have attracted continuing interest over the years because of their diverse biological activities12. A literature survey reveals that several benzothiazin-4-ones have been prepared based on different synthetic routes: a) from classic primary amine, aldehyde or ketone and thiosalicylic acid as reported by Zarghi et al.17 using p-toluenesulfonic acid catalyst in toluene reflux or as reported by Kamel et al.20 using sodium sulfate in dioxane or as reported by Kitsiou et al.21 and Silverberg et al.11 using propylphosphonic acid anhydride (T3P) as catalyst; b) from 2-aminothiophenol and chloroacetic acid as reported by Shaikh et al.16; c) from aromatic carboxylic acid with ammonium isothiocyanate as reported by Peng et al.22
Carboxylated phytosterol derivative-introduced liposomes for skin environment-responsive transdermal drug delivery system
Published in Journal of Liposome Research, 2018
Naoko Yamazaki, Satoshi Yamakawa, Takumi Sugimoto, Yuta Yoshizaki, Ryoma Teranishi, Takaaki Hayashi, Aki Kotaka, Chiharu Shinde, Takayuki Kumei, Yasushi Sumida, Toru Shimizu, Yukihiro Ohashi, Eiji Yuba, Atsushi Harada, Kenji Kono
Succinic anhydride and 1,2-cyclohexanedicarboxylic acid anhydride were obtained from New Japan Chemical Co., Ltd. (Tokyo, Japan). DMPC was obtained from NOF Corp. (Tokyo, Japan). Calcein was from Sigma-Aldrich Corp. (St. Louis, MO). Lissamine rhodamine B-sulphonylphosphatidylethanolamine (Rh-PE) was purchased from Avanti Polar Lipids Inc. (Birmingham, AL). Triton X-100 was obtained from Tokyo Chemical Industry Co. Ltd. (Tokyo, Japan). Phytosterol was provided from TAMA Biochemical Co., Ltd. (Tokyo, Japan). Its composition was ascertained using gas chromatography as β-sitosterol 46%, campesterol 25%, stigmasterol 21%, brassicasterol 3% and other sterols 5%.