by Judy, Po-shan Lai. / Thesis (M.Sc.)--Chinese University of Hong Kong, 1992. / Includes bibliographical references(leaves 83-87). / Abbreviations --- p.iii / List of Tables --- p.iv / List of Figures --- p.v / Acknowledgements --- p.vi / SUMMARY --- p.1 / Chapter 1. --- INTRODUCTION --- p.2 / Chapter 2. --- BACKGROUND --- p.4 / Chapter 2.1 --- PROBLEMS ENCOUNTERED IN THYROID FUNCTION TESTS --- p.4 / Chapter 2.2 --- A NEED FOR TISSUE MARKER VERSUS EXISTING THYROID FUNCTION TESTS --- p.8 / Chapter 2.3 --- CHOICE OF TISSUE MARKER AS AN ADJUNCT TO THYROID FUNCTION TESTS --- p.10 / Chapter 2.3.1 --- ERYTHROCYTE ZINC --- p.10 / Chapter 2.3.2 --- ERYTHROCYTE CARBONIC ANHYDRASE ISOENZYME --- p.11 / Chapter 3. --- CARBONIC ANHYDRASE --- p.14 / Chapter 3.1 --- HISTORY AND BACKGROUND --- p.14 / Chapter 3.2 --- CARBONIC ANHYDRASE ISOENZYMES --- p.15 / Chapter 3.2.1 --- STRUCTURE AND DISTRIBUTION --- p.15 / Chapter 3.2.2 --- GENERAL MECHANISMS --- p.18 / Chapter 3.2.3 --- GENETICS AND REGULATION --- p.18 / Chapter 3.2.4 --- PHYSIOLOGICAL AND CLINICAL ASPECTS --- p.20 / Chapter 4. --- ANALYTICAL METHODS FOR MEASUREMENT OF ERYTHROCYTE CARBONIC ANHYDRASE --- p.22 / Chapter 4.1 --- DETERMINATION OF ECAI USING IMMUNOTURBIDIMETRIC ASSAY --- p.23 / Chapter 4.1.1 --- PRINCIPLE OF TECHNIQUE --- p.23 / Chapter 4.1.2 --- COLLECTION AND HANDLING OF BLOOD SPECIMENS --- p.29 / Chapter 4.1.3 --- PREPARATION OF HAEMOLYSATE --- p.31 / Chapter 4.1.4 --- MEASUREMENT OF HAEMOLYSATE CAI --- p.32 / Chapter 4.1.5 --- OPTIMIZATION PROCEDURE --- p.34 / Chapter 4.1.6 --- EVALUATION EXPERIMENTS --- p.36 / Chapter 4.1.7 --- DETERMINATION OF HAEMOGLOBIN CONCENTRATION IN HAEMOLYSATE --- p.39 / Chapter 4.1.8 --- DETERMINATION OF MEAN CELL HAEMOGLOBIN CONCENTRATION --- p.41 / Chapter 4.1.9 --- CALCULATION OF ERYTHROCYTE CARBONIC ANHYDRASE I CONCENTRATION --- p.43 / Chapter 4.2 --- DETERMINATION OF ECAI USING RADIAL IMMUNODIFFUSION METHOD --- p.43 / Chapter 5. --- RESULTS OF OPTIMIZATION AND EVALUATION EXPERIMENTS --- p.46 / Chapter 5.1 --- OPTIMIZATION RESULTS --- p.46 / Chapter 5.1.1 --- WAVELENGTH --- p.46 / Chapter 5.1.2 --- PEG CONCENTRATION --- p.49 / Chapter 5.1.3 --- SAMPLE VOLUME --- p.52 / Chapter 5.1.4 --- ANTIBODY DILUTION --- p.52 / Chapter 5.1.5 --- TEMPERATURE --- p.54 / Chapter 5.1.6 --- TIME OF INCUBATION --- p.54 / Chapter 5.1.7 --- OPTIMIZED TEST PROTOCOL --- p.56 / Chapter 5.2 --- EVALUATION RESULTS --- p.56 / Chapter 5.2.1 --- STABILITY --- p.56 / Chapter 5.2.2 --- LINEARITY --- p.58 / Chapter 5.2.3 --- PRECISION --- p.62 / Chapter 5.2.3.1 --- WITHIN-RUN --- p.62 / Chapter 5.2.3.2. --- BETWEEN-RUN --- p.62 / Chapter 5.2.4 --- CROSS-REACTIVITY --- p.62 / Chapter 5.2.5 --- RECOVERY --- p.62 / Chapter 5.2.6 --- COMPARISON WITH COMPARATIVE METHOD --- p.64 / Chapter 5.3 --- DISCUSSION --- p.64 / Chapter 6. --- ECAI IN NORMAL SUBJECTS --- p.67 / Chapter 6.1 --- SUBJECTS AND METHOD --- p.67 / Chapter 6.2 --- RESULTS --- p.67 / Chapter 6.3 --- DISCUSSION --- p.67 / Chapter 7. --- PATIENT STUDY --- p.69 / Chapter 7.1 --- SUBJECTS AND METHOD --- p.69 / Chapter 7.2 --- RESULTS --- p.70 / Chapter 7.2.1 --- DEMOGRAPHIC AND BIOCHEMICAL PARAMETERS --- p.70 / Chapter 7.2.2 --- CORRELATION BETWEEN ECAI AND FT3 RESULTS OF THYROTOXIC PATIENTS BEFORE TREATMENT --- p.71 / Chapter 7.2.3 --- CORRELATION BETWEEN ECAI AND EZN RESULTS OF THYROTOXIC PATIENTS --- p.71 / Chapter 7.2.4 --- RELATIONSHIP BETWEEN THE CHANGES IN ECAI AND FT3 RESULTS IN THYROTOXIC PATIENT ON TREATMENT --- p.71 / Chapter 7.3 --- DISCUSSION --- p.76 / Chapter 8. --- GENERAL DISCUSSION --- p.79 / Chapter 9. --- REFERENCES --- p.83

Carbonic anhydases (CAs) are ubiquitous enzymes present in human under 15 different isozymes. Each active one catalyzes the hydration reaction of carbon dioxide into bicarbonate anion and proton. Some isozymes contribute to basic physiological processes like among other respiration and acid-base homeostasis while other isozymes are involved in pathologies such as epilepsy (CA VII) and cancer (CA IX). Convulsions observed during epileptic seizures are partly attributed to carbonic anhydrase VII which play a role in neuronal excitation phenomenon. Carbonic anhydrase IX (CA IX) is overexpressed in most cancer tissues and is absent from their normal counterparts. It can acidify the extratumoral medium leading to metastatic behavior. To improve our knowledge on the role of these isozymes, the design of selective CA VII and IX inhibitors is of a great interest. Otherwise, such compounds can potentially be developed as antiepileptic or anticancer agents. A molecular modeling study which combines a direct (homology modelling, docking) and an indirect (pharmacophore, virtual screening) approach of drug design was conducted to create novel and selective inhibitors. In parallel, original indanesulfonamides were designed, synthesized and their inhibitory potencies against the CAs were determined. Docking studies of some derivatives allowed to rationalize the enzymatic data. Then, we evaluated the effect of some indanesulfonamides on a model of cancer cells. The study of the anticonvulsant activity was performed on an in vivo model. Finally, during this work other series of potentially CA inhibitors were also evaluated for their CA inhibitory activities and for one of them for its anticonvulsant effect.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1943. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves xv-xvii).

Abstract Carbonic anhydrases (CAs) are a group of zinc-containing metalloenzymes that catalyze the interconversion of carbon dioxide and bicarbonate (CO2 + H2O ⇔ HCO3- + H+). They are present in almost all organs and are implicated in various biological functions, the most important of which is participation in the regulation of ion, water, and acid-base balance. Recently, some members of the CA gene family have been suggested to promote cell proliferation and to act as trophic growth factors. The present study was undertaken to examine the distribution of CA isoenzymes in the reproductive system, to attain a more detailed view on their linkage to the reproductive processes and to neonatal development. The expression of membrane-bound CA IX and CA XII was studied in the female and male reproductive tracts by immunohistochemistry and western blotting. CA XII was found to be expressed in the basolateral plasma membrane of luminal and glandular epithelia in human uterus. In human efferent ducts, it was located in the basolateral plasma membrane of luminal epithelium, where it coexpressed with Aquaporin-1. In epididymal duct, CA XII was only expressed in occasional epithelial cells. These cells coexpressed CA II, suggesting that they represent apical mitochondria-rich cells (AMRC). CA IX was also expressed in the basolateral plasma membrane of luminal epithelium in human efferent ducts, but its expression was not uniform among the tubules. These findings suggest that basolateral plasma membrane-associated CA IX and CA XII contribute, along with CA II and CA IV, to the regulation of acid-base balance and water transport in the reproductive tract. Western blotting of rat Leydig tumor cells and testis for CA II revealed an unidentified 66-kDa polypeptide band. The polypeptide was successfully purified from several rat tissues using CA inhibitor affinity chromatography. The amino acid sequence of the polypeptide showed it to be identical to NonO/p54nrb, a non-POU domain-containing octamer-binding protein previously implicated in transcriptional regulation. The recombinant NonO/p54nrb was shown to display CA activity, and the antibody to it predominantly immunostained the nuclei in lymphocytes, where CA activity was also detected histochemically. Accordingly, the nuclear Leydig cell CA immunoreactivity represents NonO/p54nrb. It is classified as a novel, nonclassical CA, and it may participate in pH-related events in the nucleus. Human and rat milk was found to contain CA VI by immunohistochemistry and western blotting. The enzyme purified from human milk by CA inhibitor affinity chromatography was confirmed by PNGase F digestion and amino acid sequence as CA VI. The CA VI concentrations in human colostral milk were approximately eight times higher than those in mature milk (34.7 mg/l vs. 4.5 mg/l). Secretion of CA VI into milk is suggested by its localization in the alveolar epithelium of the rat mammary gland. The structural and functional stability of CA VI in an acidic milieu, its suggested growth-supporting function in taste bud stem cells, and its high concentration in colostrum suggest that it is an essential factor for the growth and development of the newborn alimentary canal.

Diss. Linköping : Univ., 2003.

Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 73-77).

Thesis (Ph.D.)--University of Florida, 2004. / Typescript. Title from title page of source document. Document formatted into pages; contains 116 pages. Includes Vita. Includes bibliographical references.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-05-18T13:43:16Z No. of bitstreams: 2 Dissertação - Mariana Vieira Tomazett - 2011.pdf: 1259531 bytes, checksum: aa04f3f36448deb32394c0d322cbc8b7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-05-18T13:48:25Z (GMT) No. of bitstreams: 2 Dissertação - Mariana Vieira Tomazett - 2011.pdf: 1259531 bytes, checksum: aa04f3f36448deb32394c0d322cbc8b7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-05-18T13:48:26Z (GMT). No. of bitstreams: 2 Dissertação - Mariana Vieira Tomazett - 2011.pdf: 1259531 bytes, checksum: aa04f3f36448deb32394c0d322cbc8b7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2011-08-29 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Paracoccidioidomycosis (PCM) is the most important endemic deep mycosis in Latin America. Understanding of the complex interactions between the fungus and host must include the identification of gene expression patterns during infection. Carbonic anhydrase (CA) belongs to the family of zinc metalloenzymes that catalyzes the reversible hydratation of carbon dioxide to bicarbonate. Transcriptional studies have shown that carbonic anhydrase of P. brasiliensis is expressed in yeast cells recovered from liver of infected mice. In the present work, we characterized the cDNAs encoding for four carbonic anhydrases of P.brasiliensis (PbCA1, PbCA2, PbCA3, PbCA4). Recombinant PbCA1, 3 and 4 were obtained in heterologous systems with 33 kDa, 28 kDa and 32 kDa respectively. Mass spectrometry analysis confirmed the sequences of the produced proteins. The expression of PbCAs transcripts was evaluated by using real-time RT-PCR in mycelium, yeast cells and mycelium to yeast transition, in yeast cells exposed to CO2 and yeast cells recovery directly from liver and spleen. In the presence of CO2, PbCA1, PbCA2 and PbCA4 gene expression was reduced in the course of time. PbCA1 transcript expression was induced during the mycelium to yeast transition. PbCA2 and PbCA4 gene expression was higher in yeast cells, when compared to mycelium and mycelium to yeast transition. Pbca1 was induced yeast cells recovery directly from liver and spleen while the transcripts for Pbca2 and Pbca4 were repressed in all condictions. The gene expression data suggest differential roles of the CAs in the fungal physiology. / Paracoccidioidomicose (PCM) é a mais importante micose endêmica na América Latina. A compreensão das interações complexas entre o fungo e o hospedeiro deve incluir a identificação de padrões de expressão gênica durante a infecção. Anidrase carbônica (CA) pertence à família de metaloenzimas de zinco que catalisa a hidratação reversível do dióxido de carbono para bicarbonato. Estudos transcricionais têm mostrado que uma anidrase carbônica de P. brasiliensis é expressa em células de levedura recuperadas de fígado de camundongos infectados. No presente trabalho, nós caracterizamos os cDNAs que codificam para quatro anidrases carbônicas de P.brasiliensis (PbCA1, PbCA2, PbCA3, PbCA4). As recombinante de PbCA1, PbCA3 e PbCA4 foram obtidas em sistemas heterólogos com 33 kDa, 28 kDa e 32 kDa, respectivamente. Análise por espectrometria de massas confirmou as seqüências das proteínas produzidas. A expressão dos transcritos de Pbcas foi avaliada usando real-time RT-PCR em micélio, levedura e transição de micélio para levedura; em células de levedura expostas a CO2 e células de leveduras recuperadas diretamente do fígado e baço. Na presença de CO2, a expressão dos genes de Pbca1, Pbca2 e Pbca4 foi reduzida no decorrer do tempo. A expressão do transcrito de Pbca1 foi induzida durante a transição de micélio para levedura. A expressão de Pbca2 e Pbca4 foi maior em células de levedura, quando comparada com micélio e transição de micélio para levedura.O transcrito para Pbca1 foi induzido em células de leveduras recuperadas diretamente do fígado e baço, enquanto que os transcritos para Pbca2 e Pbca4 foram reprimidos em todas as conduções. Os dados de expressão gênica sugerem diferentes papéis das CAs na fisiologia dos fungos.

Le processus de calcification chez Corallium rubrum conduit à la formation de deux structures squelettiques composées de CaCO3, l’axe squelettique et les sclérites, de taille et de forme différentes. Comme chez de nombreuses espèces calcifiantes, la calcification se fait sous contrôle biologique impliquant notamment des enzymes et des transporteurs ioniques. Une question centrale est d’identifier les mécanismes communs ou propres à chaque espèce qui sous-tendent leur convergence fonctionnelle envers ce processus. Deux approches ont été utilisées pour caractériser ces mécanismes chez C. rubrum: 1) Une approche physiologique avec le développement d’une technique de culture de microcolonies sur lamelles permettant d’observer différents stades de calcification, et de mesurer le pH aux sites de calcification par imagerie confocale ; 2) Une approche moléculaire afin de caractériser une famille d’enzymes, les anhydrases carboniques (ACs), qui jouent un rôle clef dans la calcification.Nous avons réalisé une cartographie du pH en effectuant des mesures dans différents compartiments intra- et extracellulaires. Nos résultats montrent notamment que le pH aux sites de calcification est supérieur à celui du milieu circulant dans les canaux gastrodermiques et non à celui l’eau de mer. Les mesures d’expression différentielle des ACs dans différents tissus mettent en évidence une isozyme préférentiellement exprimée dans les cellules calcifiantes.Ces résultats intégrés dans un contexte de calcification comparée pointent sur la convergence fonctionnelle des ACs et de la régulation du pH par les cellules calcifiantes, tout en soulignant des divergences évolutives. / The calcification process in Corallium rubrum leads to the formation of two skeletal structures made of calcium carbonate, the skeletal axis and sclerites, of different size and shape. As in many calcifying species, calcification occurs under a biological control that involves enzymes and ion transporters. A central issue is to determine the common and the species-specific mechanisms of calcification in order to identify functional convergences in this process. Two approaches were used to characterize these mechanisms in C. rubrum: 1) A physiological approach involving the development of a microcolony culture technique on glass coverslips, allowing the observation of the different stages of calcification, and the measurement of pH at the sites of calcification by the use of confocal microscopy; 2) A molecular approach to characterize an enzyme family, the carbonic anhydrases, which play a key role in calcification.We performed pH mapping by making measurements in different intra- and extracellular compartments. Our results show higher pH values at the sites of calcification compared with the fluid circulating in the gastrodermal canals, but not with the seawater surrounding the microcolony. Measurements of differential expression of carbonic anhydrases in different tissue fractions highlight an isozyme preferentially expressed in the calcifying cells.Within comparative calcification perspectives, these results point towards the functional convergence of carbonic anhydrases and pH regulation by the calcifying cells, while highlighting evolutionary divergences.

Carbonic anhydrases (CAs, EC 4.2.1.1) are a class of metalloenzymes that catalyze the hydration of CO2 under physiologic conditions and are involved in many physiological and pathological processes. Modulation of CA activity, particularly CA inhibition is exploited pharmacologically for the treatment of many diseases such as cancer, glaucoma, edemas, mountain sickness. CA activation has been less frequently investigated till recently. Genetic deficiencies of several CA isozymes are reported in the literature and reflect the important role of carbonic anhydrases in human physiology and homeostasis. Activation of CA isozymes in brain have been correlated recently with spatial learning and memory. Based on these premises, activators of CA isozymes have the potential to alleviate mild dementias and to act as potential nootropic agents. In chapter 3, continuing our long-term interests towards the development of potent and selective CAAs, we carried out X-ray crystallographic studies with a small series of pyridinium histamine derivatives, previously developed as CAAs by our group. This study revealed important insights into the binding of this class of activators into the active site of CA II isozyme. A potent pyridinium histamine CAA 25i was successfully crystallized with CA II isozyme and was found to bind into the hydrophobic region of the active site, with two binding conformations being observed. This is one of the very few X-ray crystal structures of a CAA available. Based on the findings of this X-ray crystallographic study and building on our previously developed ethylene bis-imidazole CAAs, we advanced a novel series of lipophilic bis-imidazoles. Enzymatic assays carried out on purified human CA isozymes revealed several low nanomolar potent activators against various brain-relevant CA isozymes. Bis-imidazole 30e was found to be a nanomolar potent activator for CA IV, CA VA and CA IX. Due to their conjugated structure, these CAAs were also fluorescent and therefore were fully characterized in terms of photophysical properties, with several representatives proving to display very good fluorophores. The very good activation profile against several different CA isozymes, along with excellent fluorescence properties recommend these compounds as great molecular tools for elucidation of role of CA isozymes in brain physiology, as well as towards improvement of memory and learning. Focusing on inhibition of CA isozymes, it must be stressed that over the last decade a clear connection had been established between the expression of CA IX and CA XII and cancer. Since cancer is the second most common cause of death in the world, we explored the possibility to kill cancer cells via inhibition of different CA isozymes present in cancer cells. The membrane bound carbonic anhydrase IX (CA IX) isozyme represents a particularly interesting anticancer target as it is significantly overexpressed in many solid tumors as compared to normal tissues. In malign tissues this CA isozyme was found to play important role in pH homeostasis and promotes tumor cell survival, progression and metastasis. Thus, CA IX represents a potential biomarker and an appealing therapeutic target for the detection and treatment of cancer. CA IX can be targeted either through the development of small or large molecular weight, potent, and selective inhibitors or through the development of CA IX targeted drug delivery systems for selective delivery of potent chemotherapeutic agents. Building on these premises, in this dissertation, we also revealed our continuing efforts towards the development of potent and selective CA IX inhibitors along with their translation into the development of CA IX targeted drug delivery systems. In chapter 4, we designed a series of small molecular weight (MW) ureido 1,3,4-thiadiazole sulfonamide derivatives employing the “tail approach”, through the decoration of established sulfonamide CA inhibitor warheads with different tail moieties via ureido linker. The generated CAIs were tested against tumor associated CA IX and CA XII isozymes and off-target cytosolic isozymes CA I and CA II, and were revealed to be moderate to highly selective and nanomolar, even sub-nanomolar, potent CA IX inhibitors. Several potent pan-inhibitors were also identified in this section. We assessed these CAIs for their in vitro cell killing ability using MDA-MB 231 breast cancer cell line expressing CA IX and CA XII. The most efficient CAI proved to be ureido-1,3,4-thiadiazole-2-sulfonamide 69, which showed subnanomolar potency against purified human CA IX and CA XII isozymes, with good selectivity against CA I and CA II, and consistent, statistically significant cancer cell killing. In Chapter 5, continuing our efforts towards the development of potent and selective CA IX inhibitors, we designed, synthesized, characterized and evaluated a new series of PEGylated 1,3,4-thiadiazole-2-sulfonamide CAIs, bearing different PEG backbone length. We increased the PEG size from 1K to 20K, in order to better understand the impact of the PEG linker length on the in vitro cell killing ability against CA IX expressing cancer cell lines and also against a CA IX negative cell line. In vitro cell viability assays revealed the optimum PEG linker length for this type of bifunctional bis-sulfonamide CAIs in killing the tumor cells. The most efficient PEGylated CAI was found to bis-sulfonamide DTP1K 91, which showed consistent and significant cancer cell killing at concentrations of 10−100 μM across different CA IX and CA XII expressing cancer cell lines. DTP1K 91 did not affect the cell viability of CA IX negative NCI-H23 tumor cells, thus revealing a CA IX mediated cell killing for these inhibitors. In chapter 6, we decided to further explore the possibility of using CA IX as a targeting epitome for the development of a gold nanoparticle-based drug delivery system. We translated the oligoEG- and PEGylated CAI conjugates into efficient targeting ligands for gold nanoparticle decoration along with chemotherapeutic agent doxorubicin (Dox), in a novel multi-ligand gold nanoplatform designed to selectively release the drug intracellularly, in order to enhance the selective tumor drug uptake and tumor killing. We were successful in developing compatible CAI- and Dox- ligands for efficient dual functionalization of gold nanoparticles. Our optimized, CA IX targeted gold nanoplatform was found to be very efficient towards killing HT-29 tumor cells especially under hypoxic conditions, reducing the hypoxia-induced chemoresistance, thus confirmed the potentiating role of CA IX as a targeting epitome. / Pharmaceutical Sciences