Design, synthesis, in vitro inhibition and toxicological evaluation of human carbonic anhydrases I, II and IX inhibitors in 5-nitroimidazole series

With the aim to obtain novel compounds possessing both strong affinity against human carbonic anhydrases and low toxicity, we synthesised novel thiourea and sulphonamide derivatives 3, 4 and 10, and studied their in vitro inhibitory properties against human CA I, CA II and CA IX. We also evaluated the toxicity of these compounds using zebrafish larvae. Among the three compounds, derivative 4 showed efficient inhibition against hCA II (KI = 58.6 nM). Compound 10 showed moderate inhibition against hCA II (KI = 199.2 nM) and hCA IX (KI = 147.3 nM), whereas it inhibited hCA I less weakly at micromolar concentrations (KI = 6428.4 nM). All other inhibition constants for these compounds were in the submicromolar range. The toxicity evaluation studies showed no adverse effects on the zebrafish larvae. Our study suggests that these compounds are suitable for further preclinical characterisation as potential inhibitors of hCA I, II and IX

Kirurginen savu toimenpiteissä - henkilöstön riskit ja suojaus

• Monia sähkökirurgisia instrumentteja käytettäessä syntyy kirurgista savua. • Henkilöstö voi altistua kumulatiivisesti savun haitallisille komponenteille. • Tavallinen kirurginen hengityssuojain antaa yli 90-prosenttisen suojan. Lisäksi tulisi käyttää asianmukaisella suodattimella varustettua paikallista savunpoistolaitteistoa. • Savulle altistumisen ei ole osoitettu lisäävän sairastavuutta tai syöpäriskiä.</p

Kirurginen savu toimenpiteissä - henkilöstön riskit ja suojaus

Vertaisarvioitu• Monia sähkökirurgisia instrumentteja käytettäessä syntyy kirurgista savua. • Henkilöstö voi altistua kumulatiivisesti savun haitallisille komponenteille. • Tavallinen kirurginen hengityssuojain antaa yli 90-prosenttisen suojan. Lisäksi tulisi käyttää asianmukaisella suodattimella varustettua paikallista savunpoistolaitteistoa. • Savulle altistumisen ei ole osoitettu lisäävän sairastavuutta tai syöpäriskiä.Peer reviewe

Characterization of the first beta-class carbonic anhydrase from an arthropod (Drosophila melanogaster) and phylogenetic analysis of beta-class carbonic anhydrases in invertebrates

BACKGROUND: The beta-carbonic anhydrase (CA, EC 4.2.1.1) enzymes have been reported in a variety of organisms, but their existence in animals has been unclear. The purpose of the present study was to perform extensive sequence analysis to show that the beta-CAs are present in invertebrates and to clone and characterize a member of this enzyme family from a representative model organism of the animal kingdom, e.g., Drosophila melanogaster. RESULTS: The novel beta-CA gene, here named DmBCA, was identified from FlyBase, and its orthologs were searched and reconstructed from sequence databases, confirming the presence of beta-CA sequences in 55 metazoan species. The corresponding recombinant enzyme was produced in Sf9 insect cells, purified, kinetically characterized, and its inhibition was investigated with a series of simple, inorganic anions. Holoenzyme molecular mass was defined by dynamic light scattering analysis and gel filtration, and the results suggested that the holoenzyme is a dimer. Double immunostaining confirmed predictions based on sequence analysis and localized DmBCA protein to mitochondria. The enzyme showed high CO2 hydratase activity, with a kcat of 9.5 x 105 s-1 and a kcat/KM of 1.1 x 108 M-1s-1. DmBCA was appreciably inhibited by the clinically-used sulfonamide acetazolamide, with an inhibition constant of 49 nM. It was moderately inhibited by halides, pseudohalides, hydrogen sulfide, bisulfite and sulfate (KI values of 0.67 - 1.36 mM) and more potently by sulfamide (KI of 0.15 mM). Bicarbonate, nitrate, nitrite and phenylarsonic/boronic acids were much weaker inhibitors (KIs of 26.9 - 43.7 mM). CONCLUSIONS: The Drosophila beta-CA represents a highly active mitochondrial enzyme that is a potential model enzyme for anti-parasitic drug development

Expression of a novel carbonic anhydrase, CA XIII, in normal and neoplastic colorectal mucosa

BACKGROUND: Carbonic anhydrase (CA) isozymes may have an important role in cancer development. Some isozymes control pH homeostasis in tumors that appears to modulate the behaviour of cancer cells. CA XIII is the newest member of the CA gene family. It is a cytosolic isozyme which is expressed in a number of normal tissues. The present study was designed to investigate CA XIII expression in prospectively collected colorectal tumor samples. METHODS: Both neoplastic and normal tissue specimens were obtained from the same patients. The analyses were performed using CA XIII-specific antibodies and an immunohistochemical staining method. For comparison, the tissue sections were immunostained for other cytosolic isozymes, CA I and II. RESULTS: The results indicated that the expression of CA XIII is down-regulated in tumor cells compared to the normal tissue. The lowest signal was detected in carcinoma samples. This pattern of expression was quite parallel for CA I and II. CONCLUSION: The down-regulation of cytosolic CA I, II and XIII in colorectal cancer may result from reduced levels of a common transcription factor or loss of closely linked CA1, CA2 and CA13 alleles on chromosome 8. Their possible role as tumor suppressors should be further evaluated

Terveydenhuollon menetelmien arviointi on yhä tärkeämpää

Tervey­den­huollon mene­telmien ar­vioinnin asema tu­lee tur­vata ­lain­sää­dän­nöllä, riittä­vällä resur­soin­nilla, teke­mällä suosi­tuk­sista velvoit­tavia ja kytke­mällä ne talou­del­liseen oh­jaukseen

Проект системы оборотного водоснабжения для охлаждения гальванических ванн

Объект разработки: Кожухотрубчатый теплообменник. Цель работы: Рассчитать теплообменник для охлаждения оборотной воды. В ходе выполнения работы: Выполнены все необходимые расчеты для конструирования аппарата. Определены размеры и основные механические характеристики. Основные конструктивные, технологические и технико-эксплуатационные характеристики: Диаметр аппарата 159 мм, длина теплообменных труб 3 м, диаметр труб 25х2 мм, рабочее давление трубного пространства 0,2Development object: Shell and tube heat exchanger. Purpose of work: Calculate a heat exchanger for cooling the circulating water. In the course of the work: All the necessary calculations for the design of the apparatus have been completed. The dimensions and main mechanical characteristics are determined. The main design, technological and technical and operational characteristics: The diameter of the apparatus is 159 mm, the length of the heat exchange tubes is 3 m, the diameter of the tube

Beta carbonic anhydrases: novel targets for pesticides and anti-parasitic agents in agriculture and livestock husbandry

Abstract BACKGROUND: The genomes of many insect and parasite species contain beta carbonic anhydrase (β-CA) protein coding sequences. The lack of β-CA proteins in mammals makes them interesting target proteins for inhibition in treatment of some infectious diseases and pests. Many insects and parasites represent important pests for agriculture and cause enormous economic damage worldwide. Meanwhile, pollution of the environment by old pesticides, emergence of strains resistant to them, and their off-target effects are major challenges for agriculture and society. METHODS: In this study, we analyzed a multiple sequence alignment of 31 β-CAs from insects, some parasites, and selected plant species relevant to agriculture and livestock husbandry. Using bioinformatics tools a phylogenetic tree was generated and the subcellular localizations and antigenic sites of each protein were predicted. Structural models for β-CAs of Ancylostoma caninum, Ascaris suum, Trichinella spiralis, and Entamoeba histolytica, were built using Pisum sativum and Mycobacterium tuberculosis β-CAs as templates. RESULTS: Six β-CAs of insects and parasites and six β-CAs of plants are predicted to be mitochondrial and chloroplastic, respectively, and thus may be involved in important metabolic functions. All 31 sequences showed the presence of the highly conserved β-CA active site sequence motifs, CXDXR and HXXC (C: cysteine, D: aspartic acid, R: arginine, H: histidine, X: any residue). We discovered that these two motifs are more antigenic than others. Homology models suggested that these motifs are mostly buried and thus not well accessible for recognition by antibodies. CONCLUSIONS: The predicted mitochondrial localization of several β-CAs and hidden antigenic epitopes within the protein molecule, suggest that they may not be considered major targets for vaccines. Instead, they are promising candidate enzymes for small-molecule inhibitors which can easily penetrate the cell membrane. Based on current knowledge, we conclude that β-CAs are potential targets for development of small molecule pesticides or anti-parasitic agents with minimal side effects on vertebratesBioMed Central open acces