Biochemical and Pharmacological Properties of Biogenic Amines

Biogenic amines are low molecular weight organic nitrogen compounds. They are formed by the decarboxylation of amino acids or by amination and transamination of aldehydes and ketones during normal metabolic processes in living cells and therefore are ubiquitous in animals, plants, microorganisms, and humans. In food and beverages, they are formed by the enzymes of raw materials or are generated by microbial decarboxylation of amino acids. The structure of a biogenic amine can be aromatic and heterocyclic amines (histamine, tryptamine, tyramine, phenylethylamine, and serotonin); aliphatic di-, tri-, and polyamines (putrescine, cadaverine, spermine, spermidine, and agmatine); and aliphatic volatile amines (ethylamine, methylamine, isopentylamine, and ethanolamine). Many of them possess a strong pharmacologic effect, and others are important as precursors of hormones and components of coenzymes. The biogenic amine intoxication leads to toxicological risks and health hazards that trigger psychoactive, vasoactive, and hypertensive effects resulting from consumption of high amounts of biogenic amines in foods. The toxicological effects of biogenic amines increase when the mono- and diaminoxidase enzymes are deficient or drugs that inhibit these enzymes (pain reliever, stress, and depression drugs) are used. In this chapter, biosynthesis of biogenic amines, their toxic effects as well as their physiological functions, and their effect on health will be described

Cost effective filamentous phage based immunization nanoparticles displaying a full-length hepatitis B virus surface antigen

Hepatitis B virus (HBV) is one of the major causes of chronic hepatitis, cirrhosis and liver cancer. In combating HBV infections, HBV diagnosis and vaccination are therefore critical. The hepatitis B virus surface antigen (HBsAg) is a key target molecule in developing vaccines and diagnostic systems. To date, although HBsAg has been expressed in bacteria, yeasts and mammalian cells, there are still limitations in the existing ones, which leave the necessity for searching new HBsAg production methods. In this study, a simple phage display-based method was developed to produce the purified full-length HBsAg molecules for further immunization studies. For this purpose, the HBsAg coding gene was cloned into a pCANTAB5E phagemid vector and expressed on the surface of M13 filamentous phages. The HBsAg-expressing phage nanosystem was then used as immunization agent in BALB/cJ mice. The ELISA results for sera obtained from mice immunized with HBsAg-displaying phage particles revealed an immune response against HBsAg. These results demonstrate the potential use of a full-length antigen to be displayed on phages as cost effective adjuvant-free immunization agents as an alternative to the highly purified and more expensive antigens conjugated with carrier molecules

Pyogenic granuloma: a rare case of an infantile intraoral lesion

Pyogenic granuloma (PG) is a non-neoplastic inflammatory hyperplasia that may be encountered in any part of the body including the oral mucosa. The onset of symptoms is mostly observed at adolescence in children. In this presentation, the second youngest case of gingival PG in the literature is reported to provide an insight into early neonatal gingival masses, which may be a stress factor for both the parents and the physician. A 4-month-old male baby was referred to our clinic with the complaint of erythema and swelling at the upper gingival floor, which was first observed 2 months ago by his mother before his admission. At physical examination, a soft, hyperemic mucosal lesion was observed that protruded from the upper gingival floor. After the excision, granulomatous-type PG was diagnosed. The excision site healed and the postoperative period was uneventful. The gingiva is the most common intraoral site of PG as in our case, but this localization is specific for the older age group rather than in infants. Intraoral lesions of neonatal period are unfamiliar to the parents resulting in their anxiety. The PG is a benign lesion that can be healed completely, with good cosmetic results. Keywords: gingiva, infant, intraoral, pyogenic granulom

Malathion ve Onosma nigricaule (Boraginaceae)'nin fare böbrek dokusunda katalaz (CAT) ve süperoksit dismutaz-2 (Mn-SOD) salınımı üzerine etkileri]

The purpose of this study was to determine the effects of the plant extract, which is obtained from Onosma nigricaule due to the oxidation parameters caused in mice by malathion that is used as an insecticide in agriculture, on catalase (CAT) and superoxide dismutase-2 (Mn-SOD) in kidney tissues by immunohistochemical technique. A total of 48 male mice (Mus musculus) were used in our study. Mice were divided 6 groups (control group, maize oil group, normal saline group, Onosma nigricaule group, malathion group, Onosma nigrcaule+malathion group). Hematoxylin-eosin and triple staining methods were used for histological and pathological examinations. The localization of CAT and Mn-SOD in the renal tissue was determined using the method of streptavidinbiotin- peroxidase. CAT immunoreactivity was determined with a weak intensity in epithelium of renal tubulus proximalis of mice in the malathion group, with a moderate intensity in Onosma nigricaule+ malathion group and with a higher intensity in tubulus proximalis of other groups. A cytoplasmic Mn-SOD immunoreactivity was determined with weak intensity in renal medulla of mice in malathion group, with moderate intensity in renal medulla of mice in Onosma nigricaule plant extract+ malathion group, maize oil group, and normal saline group and with highly intensity in control and Onosma nigricaule groups. It was concluded that Onosma nigricaule might play a protective role as an antioxidant against the oxidant features of malathion.Kafkas University, BAPKafkas University [2013-KSYO-78]This research was supported by a grant from the Kafkas University, BAP (Project No: 2013-KSYO-78

Cloning of anti-hbsag single chain variable fragments from hybridoma cells for one-step elisa

Hepatitis B virus (HBV) infection is a worldwide health problem. More than 400 million people are chronic HBV carriers in the world. Infected individuals are at a high risk of developing liver cirrhosis and hepatocellular carcinoma as the main consequences of HBV. The discoveries of fast diagnostic systems and new therapeutic applications are crucial in the fight against viral hepatitis. In this paper we present the generation of a single-chain variable fragment (scFv) from a mouse monoclonal antibody specific to the HBV surface antigen (HBsAg) and demonstrate its expression as a bacterial alkaline phosphatase (AP) fusion protein. In this study, we constructed scFvs from hybridoma cells expressing HBsAg-specific antibody using phage display technology and expressed them in Escherichia coli. The anti-HBsAg scFvs were inserted into pQE-2 vector to produce scFv antibody genetically fused to bacterial AP. Reproducibility of the recombinant HBsAg-scFv fusion protein was tested using Enzyme-linked Immunosorbent Assay (ELISA). Present preliminary findings indicate that the anti-HBsAg-scFv AP conjugate could be further used for the development of one-step ELISA for the detection of HBV

Antimicrobial Peptides and Skin: A Paradigm of Translational Medicine

Antimicrobial peptides (AMPs) are small, cationic, amphiphilic peptides with broad-spectrum microbicidal activity against both bacteria and fungi. In mammals, AMPs form the first line of host defense against infections and generally play an important role as effector agents of the innate immune system. The AMP era was born more than 6 decades ago when the first cationic cyclic peptide antibiotics, namely polymyxins and tyrothricin, found their way into clinical use. Due to the good clinical experience in the treatment of, for example, infections of mucus membranes as well as the subsequent understanding of mode of action, AMPs are now considered for treatment of inflammatory skin diseases and for improving healing of infected wounds. Based on the preclinical findings, including pathobiochemistry and molecular medicine, targeted therapy strategies are developed and first results indicate that AMPs influence processes of diseased skin. Importantly, in contrast to other antibiotics, AMPs do not seem to propagate the development of antibiotic-resistant micro-organisms. Therefore, AMPs should be tested in clinical trials for their efficacy and tolerability in inflammatory skin diseases and chronic wounds. Apart from possible fields of application, these peptides appear suited as an example of the paradigm of translational medicine for skin diseases which is today seen as a `two-way road' - from bench to bedside and backwards from bedside to bench. Copyright (c) 2012 S. Karger AG, Base

Identification of novel neutralizing single-chain antibodies against vascular endothelial growth factor receptor 2

Human vascular endothelial growth factor (VEGF) and its receptor (VEGFR-2/kinase domain receptor [KDR]) play a crucial role in angiogenesis, which makes the VEGFR-2 signaling pathway a major target for therapeutic applications. In this study, a single-chain antibody phage display library was constructed from spleen cells of mice immunized with recombinant human soluble extracellular VEGFR-2/KDR consisting of all seven extracellular domains (sKDR D1-7) to obtain antibodies that block VEGF binding to VEGFR-2. Two specific single-chain antibodies (KDR1.3 and KDR2.6) that recognized human VEGFR-2 were selected; diversity analysis of the clones was performed by BstNI fingerprinting and nucleotide sequencing. The single-chain variable fragments (scFvs) were expressed in soluble form and specificity of interactions between affinity purified scFvs and VEGFR-2 was confirmed by ELISA. Binding of the recombinant antibodies for VEGFR-2 receptors was investigated by surface plasmon resonance spectroscopy. In vitro cell culture assays showed that KDR1.3 and KDR2.6 scFvs significantly suppressed the mitogenic response of human umbilical vein endothelial cells to recombinant human VEGF 165 in a dose-dependent manner, and reduced VEGF-dependent cell proliferation by 60% and 40%, respectively. In vivo analysis of these recombinant antibodies in a rat cornea angiogenesis model revealed that both antibodies suppressed the development of new corneal vessels (p < 0.05). Overall, in vitro and in vivo results disclose strong interactions of KDR1.3 and KDR2.6 scFvs with VEGFR-2. These findings indicate that KDR1.3 and KDR2.6 scFvs are promising antiangiogenic therapeutic agents. © 2011 International Union of Biochemistry and Molecular Biology, Inc