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Polymers as Conditioning Agents for Hair and Skin
Published in Randy Schueller, Perry Romanowski, Conditioning Agents for Hair and Skin, 2020
AMPHOMER is an amphoteric acrylic resin developed specifically as a hair fixative. It is carboxylated at regular intervals along its molecular chain. The amphoteric character gives the polymer good curl retention, ease of combing, and conditioning effect.
3-MethylcrotonylCoA carboxylase deficiency/3-methylcrotonylglycinuria
Published in William L. Nyhan, Georg F. Hoffmann, Aida I. Al-Aqeel, Bruce A. Barshop, Atlas of Inherited Metabolic Diseases, 2020
William L. Nyhan, Georg F. Hoffmann, Aida I. Al-Aqeel, Bruce A. Barshop
3-MethylcrotonylCoA carboxylase (EC 6.4.1.4) deficiency (Figure 10.1) is a disorder of leucine catabolism in which elevated quantities of 3-hydroxyisovaleric acid and 3-methylcrotonylglycine are found in the urine. The disorder is often referred to as isolated 3-methylcrotonylCoA carboxylase deficiency, to distinguish it from multiple carboxylase deficiency, as early reports and the majority of subsequent symptomatic patients with 3-methylcrotonylglycinuria had biotin-responsive multiple carboxylase deficiency as a consequence of deficiency of holocarboxylase synthetase (Chapter 6) or biotinidase (Chapter 7) [1, 2]. The disease was considered to be rare [3–11], until the development of programs of neonatal screening began turning up in so many patients that this disorder is being considered the most common of the organic acidemias [12]. In some instances of detection through newborn screening, it is the mother, not the newborn, who has 3-methylcrotonylCoA carboxylase deficiency. The enzyme has two (MCCa and MCCb) subunits and the A and B genes have been cloned, and mutations in each have been defined [13–16].
Brittle Nails
Published in Nilton Di Chiacchio, Antonella Tosti, Therapies for Nail Disorders, 2020
Biotin is a water-soluble vitamin component of the B complex that acts as a coenzyme for several human carboxylases. Biotin deficiency is exceedingly rare and may be inherited or acquired. Acquired forms may occur in cases of severe malnutrition, total parenteral nutrition without biotin supplementation, long-term anticonvulsant or antibiotic therapy, and ingestion of raw egg whites. Inherited conditions include biotinidase deficiency and multiple carboxylase deficiency.
Anti-obesity carbonic anhydrase inhibitors: challenges and opportunities
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2022
In the last period, CAs were not only considered as being involved in pH regulation/buffering in many cells and tissues, but also as metabolic enzymes16, due to their demonstrated role in several metabolic processes in tumours17,18 and normal cells, including fatty acid biosynthesis and de novo lipogenesis (DNL) – Figure 12,8–12. It has been known for decades that fatty acid biosynthesis and DNL involve both mitochondrial and cytosolic steps, in which several enzymes implicated both in the Krebs cycle as well as DNL, among which pyruvate carboxylase (PC) and acetyl-coenzyme A carboxylase (ACC) use bicarbonate and not CO2 as one of their substrate8–12. In order to achieve the very rapid interconversion between these two species, highly catalytically active CA isoforms (among which CA II in the cytosol13–15 and CA VA/VB in the mitochondria19,20) are necessary to participate21–25. It has been demonstrated already in the 90 s that this is indeed the case, and that inhibition of mitochondrial/cytosolic CAs interferes with fatty acid biosynthesis and DNL in various cells, tissues and animal models21–25.
A pilot study on machine learning approach to delineate metabolic signatures in intellectual disability
Published in International Journal of Developmental Disabilities, 2021
Vidya Nikam, Suvidya Ranade, Naushad Shaik Mohammad, Mohan Kulkarni
The analytes were correlated with demographic characters using Kendall–Tau matrix. 3-Hydroxyisovalerylcarnitine (C5OH) is an indicator for diagnoses of 3-methylcrotonyl-CoA carboxylase deficiency reported to be associated with mild developmental delay (Maeda et al.2008). Decreased levels of acylcarnitines were reported to be associated with neurodegenerative disorders with a major impact on the motor function (Saiki et al.2017). Glutamate results from proline catabolism by aldehyde dehydrogenase and via an aminotransferase enzyme helps in the synthesis of alanine. Glutamate is a main excitatory neurotransmitter and abnormal glutamate signaling is thought to contribute to the pathogenesis of a variety of neurodevelopmental disorders (Fedder and Sabo 2015). This could be explained why subjects with elevated proline and alanine would be having an early onset of ID. Elevated levels of C5 acylcarnitine are characteristic of isovaleric acidemia with clinical features suggestive of significant motor delay (Ensenauer et al.2011). Glycine is an inhibitory neurotransmitter of the central nervous system and its upsurge blood levels are delineated to be a cause of glycine encephalopathy with seizures and speech delay as the major clinical manifestations (Hennermann 2006). The study indicates that Kendall–Tau matrix could efficiently correlate analytes and demographic milestones which match with the reported literature.
Liposome–ligand conjugates: a review on the current state of art
Published in Journal of Drug Targeting, 2020
This is the most frequently used linkage in terms of engineering liposome conjugates. Ester bond is formed when hydroxyl group of a molecule reacts (sometimes with the help of succinic acid as linkers) with carboxylic acid group of the liposomes or vice versa [100]. Because of the unreactive nature of carboxyl groups (due to low nucleophilic property), reactants such as carbonyl diimidazole are used to modify these carboxyl groups to make room for ester linkages. Carbonyl diimidazole is an active carbonylating agent consisting of two acylimidazole-leaving groups that react with carboxylic acids to generate N-acylimidazoles of high reactivity. The active carboxylate resulting from this reaction is then positioned to bond with hydroxyl groups through ester linkages [64]. This bond is usually meant to be broken by esterase enzymes through the process of hydrolysis; but then several factors including adjacent groups (e.g. bromide) and spacers may influence the cleavage process [101,102]. Guo and Szoka [103] utilised diortho ester to successfully synthesise low pH-sensitive PEG-diortho ester-distearoyl glycerol conjugate (POD). Distearoyl glycerol containing two saturated hydrocarbon side chains is coupled to the diortho ester (3,9-diethyl-2,4,8,10-tetraoxaspiro[5]undecane) in order to facilitate the anchoring of PEG2000 into lipid bilayers. The formed liposome conjugate was found to be stable up to 12 h at neutral pH, but degraded at pH 5 to release the payload, and thus found to be suitable for application in tumour targeting.