The minimal effective concentration of the pituitary insulin secretagogue beta-cell-tropin (beta-CT) on the in vitro perfused pancreas was established and the effects of various modifications of the peptide on its potency were tested: iodination with 127I and acetylation reduced the insulin-releasing activity of beta-cell-tropin, and the C-terminal fragments beta-CT-(2-18), beta-CT-(3-18) and b...

Abstract Flavin‐dependent halogenases (FDHs) natively catalyze selective halogenation of electron rich aromatic and enolate groups. Nearly all FDHs reported to date require a separate flavin reductase supply them with FADH 2 , which complicates biocatalysis applications. In this study, we establish that the single component reductase/flavin dependent halogenase AetF catalyzes diverse set substr...

Membranes were purified from rat muscle by a differential centrifugation method that avoids the use of salt extraction or incubations at elevated temperature. Three populations of membrane-limited vesicles were defined having average densities of 1.112 (fraction I), 1.141 (fraction II), and 1.158 (fraction III) g/ml in a continuous sucrose gradient. Lactoperoxidase-catalyzed iodination of intac...

The S-acetamidomethyl (Acm) or trityl (Trt) protecting groups are widely used in the chemical synthesis of peptides that contain one or more disulfide bonds. Treatment of peptides containing S-Acm protecting group with iodine results in simultaneous removal of the sulfhydryl protecting group and disulfide formation. However, the excess iodine needs to be quenched or adsorbed as quickly as possi...

PURPOSE We designed our study to evaluate the hypothesis that gastric cancer is correlated with iodine deficiency or thyroid dysfunction. MATERIALS AND METHODS We investigated the total body iodine reserve, thyroid function status and autoimmune disorder in 40 recently diagnosed gastric adenocarcinoma cases versus 80 healthy controls. The participants came from a region with high gastric canc...

Thyroid disorders are common worldwide.1 In Africa, dietary iodine deficiency is the major determinant of thyroid pathology, resulting in a spectrum of iodine deficiency disorders, including goitres, hypothyroidism and mental retardation.2 Of these, mental retardation poses the most severe threat to socioeconomic wellbeing; thus, its prevention has been the focus of current global efforts towar...

Iodine is one of the best-characterized environmental factors associated with autoimmune thyroid disease (ATD). Epidemiological studies have shown that ATD incidence has increased following the introduction of salt iodination in the 1920s; in addition, ATD patients can improve upon iodine restriction. In animal models such as BioBreeding/Worcester and Buffalo rats, obese chicken strain, and non...

Computational chemistry has shown that backbone-alkylated imidazoles ought to be efficient ligands for transition metal catalysts with improved carbene-to-metal donation. In this work, such alkylated imidazoles were synthesized and complexed with silver(I) by means of an eight/nine-step synthetic pathway we devised to access a new class of biologically active silver complexes. The synthesis inv...

A fast and efficient nickel-catalysed iodination reaction of aryl and heteroaryl bromides has been developed. The transformation was found to be general for a wide range of substrates and was used for the synthesis of iodo-PK11195, an imaging agent of Alzheimer's disease and iniparib, a compound used in the treatment of breast cancer.

Benzene, halobenzenes and some deactivated arenes readily reacted in anhydrous NaIO4/AcOH/Ac2O/concd. H2SO4 mixtures to afford, after quenching with excess aqueous Na2SO3 solution (a reducing agent), purified iodinated products in 27-88% yields. This novel method of aromatic iodination is simple, fairly effective and environmentally safe.