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A general discussion of melting and premelting is given. Crystal structures and phase transitions in the C-forms of stearic, palmitic, myristic and lauric acids and in anhydrous sodium stearate are also discussed. Simple theories of infrared and nuclear magnetic resonance spectrometry are presented. Experimental difficulties in the use of solid phase infrared spectra are discussed. A detailed study is made of the temperature behaviour of the infrared spectra of the fatty acids in the region from 750 to 700 cm¯¹ and over the range from about 70ºC below the melting points to about 20ºC above them. Three overlapping peaks of different intensity are resolved - 720 cm¯¹, about 727 cm¯¹, and a peak at higher frequency the position of which varies in the different acids. The complete disappearance of the 720 cm¯¹ band slightly below the melting point in each acid is taken to indicate a transition, not previously reported, to a disordered phase in which there is considerable molecular motion as evidenced by the phase's liquid-like spectra. The presence of three peaks in the region is discussed on the basis of a simple theoretical expression derived by Snyder for the position of fundamental methylene rocking vibrations. The crystallinities of the acids are estimated from an expression, based on the work of Stein and Sutherland, which involves the apparent integrated absorption intensities of the resolved 720 and 727 cm¯¹ bands. The extent of premelting is determined. Extensive premelting giving the spectra a liquid-like, but not completely liquid character is found to take place within about 2ºC of the melting point. The high resolution nuclear magnetic resonance spectra of anhydrous sodium stearate were taken at the limit of their experimental application. The spectra show, however, that the subwaxy, waxy, superwaxy and subneat phases of anhydrous sodium stearate form a structurally similar group (from about 120 to 235ºC) with liquid-crystalline properties, while the neat and melt phases also form a structurally similar group (from 235º C upwards) but with the properties of a liquid. The information indicates extensive premelting beginning in the vicinity of 120ºC, below which temperature the salt is essentially crystalline, which reaches a climax at 235ºC, above which temperature the salt is essentially liquid. / Science, Faculty of / Chemistry, Department of / Graduate

The kinase interaction motif (KIM) family of protein-tyrosine phosphatases (PTPs) includes hematopoietic protein-tyrosine phosphatase (HePTP), striatal-enriched protein-tyrosine phosphatase (STEP), and protein-tyrosine phosphatase receptor type R (PTPRR). KIM-PTPs bind and dephosphorylate mitogen-activated protein kinases (MAPKs) and thereby critically modulate cell proliferation and differentiation. PTP activity can readily be diminished by reactive oxygen species (ROS), e.g. H2O2, which oxidize the catalytically indispensable active-site cysteine. This initial oxidation generates an unstable sulfenic acid intermediate that is quickly converted into either a sulfinic/sulfonic acid (catalytically dead and irreversible inactivation) or a stable sulfenamide or disulfide bond intermediate (reversible inactivation). Critically, our understanding of ROS-mediated PTP oxidation is not yet sufficient to predict the molecular responses of PTPs to oxidative stress. However, identifying distinct responses will enable novel routes for PTP-selective drug design, important for managing diseases such as cancer and Alzheimer's disease. Therefore, we performed a detailed biochemical and molecular study of all KIM-PTP family members to determine their H2O2 oxidation profiles and identify their reversible inactivation mechanism(s). We show that despite having nearly identical 3D structures and sequences, each KIM-PTP family member has a unique oxidation profile. Furthermore, we also show that whereas STEP and PTPRR stabilize their reversibly oxidized state by forming an intramolecular disulfide bond, HePTP uses an unexpected mechanism, namely, formation of a reversible intermolecular disulfide bond. In summary, despite being closely related, KIM-PTPs significantly differ in oxidation profiles. These findings highlight that oxidation protection is critical when analyzing PTPs, for example, in drug screening.

Orientador: / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-18T16:30:22Z (GMT). No. of bitstreams: 1 Pinheiro_GlauciaMelinaSquizato_M.pdf: 10487701 bytes, checksum: fedb6a8be09bd0cb49b2fe1aaca9ba90 (MD5) Previous issue date: 2011 / Resumo: Este trabalho descreve um estudo teórico-experimental envolvendo derivados da Piridostigmina e do Edrofônio, que possuem ação como inibidores da enzima acetilcolinesterase. Os anticolinesterásicos são utilizados como medicamento para o tratamento do Mal de Alzheimer. Primeiramente foram sintetizados os derivados da Piridostigmina (brometo de N,N-dimetilcarbamato de N'-metilpiridínio), com substituintes no carbono 5 do anel piridínico: fenila, p-metoxifenila, p-nitrofenila, p-clorofenila, e um derivado do Edrofônio (brometo de 2,6-tetraidro-N,N-dimetil-3-hidroxi-5-fenilpiridínio). O procedimento proposto envolveu como intermediários os 2,6-tetraidro-N,N-dimetil-3-oxo-5-fenilpiridínio p-substituídos, com estrutura de sal interno (cargas negativa e positiva no oxigênio e nitrogênio, respectivamente). Todos os compostos tiveram suas propriedades físico-químicas (ponto de fusão, análise elementar) e espectroscópicas (RMN e IV) analisadas, tanto para os sais cíclicos intermediários como para os produtos finais. Através de cálculos teóricos analisamos as geometrias moleculares e densidades de carga dos compostos finais. Investigamos também as propriedades biológicas referentes à atividade anticolinesterásica do derivado do Edrofônio determinada através do Método de Ellman modificado. Neste teste observamos que este composto possui uma atividade anticolinesterásica superior ao fármaco comercial, sendo que, o fármaco comercial inibiu 62,9% a atividade enzimática total, contra 100% de inibição do composto, ambos na concentração de 0,1 mol / L / Abstract: This project describes a theoretical and experimental study involving pyridostigmine and edrophonium derivatives, which can be used as inhibitors of the acetylcholinesterase enzyme. The anticholinesterase agents are used as medicine for the treatment of Alzheimer's disease. Firstly pyridostigmine (N,N-dimethylcarbamate N'-methyl-5-phenyl-pyridinium bromides) derivatives (phenyl, p-nitrophenyl, p-chlorophenyl, p-methoxyphenyl) and 2,6-tetrahydro-N,N-dimethyl-3-hidroxy-5-phenylpyridine bromide (edrophonium derivative) were prepared. All compounds were characterized from their physicochemical (melting point, elemental analysis) and a spectroscopic property (NMR and IR) for both cyclic salts intermediates and the final products. Through theoretical calculations it has been assessed molecular geometries and charge densities of the final compounds. It has also been investigated the biological properties related to the activity of anticholinesterase edrophonium derivative, which was accessed from modified Ellman method. It has been found that edrophonium derivative present anticholinesterase activity much higher than the commercially available drug. From our results, while commercial drug inhibit 62.9% of the total enzyme activity, edrophonium derivative inhibit 100%, both at the same concentration (0.1 mol L-1) / Mestrado / Ciencias Biomedicas / Mestre em Ciências Médicas

Orientador: Claudio Francisco Tormena / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-14T14:30:02Z (GMT). No. of bitstreams: 1 Santos_FranciscoPaulodos_D.pdf: 15350887 bytes, checksum: 67e192401b6f5d14d6d2568ea89baff1 (MD5) Previous issue date: 2009 / Resumo: A tese está estruturada da seguinte forma. Primeiro uma parte introdutória relatando o efeito das interações hiperconjugativas na constante de acoplamento JXY e uma discussao sobre a as principais metodologias para a determinação de constantes de acoplamento a JXY a longa distância. Nesta primeira parte o leitor e introduzido nos tópicos básicos desta tese. Seguindo o corpo da tese contém os resultados e discussão. Primeiro apresentamos as metodologias para determinação das constantes de acoplamento JCH com enfase para o experimento de HSQMBC e para os experimentos de estado de spin seletivo (HSQC-TOCSY-IPAP e HSQC-TOCSY-IPAP-triplamente editado). Posteriormente apresentamos uma racionalização para a diferença entre os acoplamentos JC4H1 e JC1H4 da 3-exo-2-norbornanona (X = Cl, Br, SCH3). Mostramos que ambos os acoplamentos JC1H e JC4H14 deveriam apresentar uma redução de seus valores, devido as interações hiperconjugativas sC1-C7p*C2=O e sC1-C7s*C2=O que retiram densidade eletrônica do caminho a três ligações.Entretanto, observamos que a existência de uma terceira interação sC3-C4s*C2-O recupera parte da densidade eletrônica do acoplamento JC4H1 através de um caminho adicional a quatro ligações fazendo com que o acoplamento JC4H1 seja maior. Este caminho a quatro ligações é similar ao observado em sistemas homoalílicos, sendo que a principal diferença é a natureza do orbital antiligante, que para nossos sistemas é um orbital do tipo s, enquanto para os homoalílicos é do tipo p. / Abstract: In the introduction, it is presented a discussion about the effect of hyperconjugative interactions on coupling constants and a discussion about some methodologies for the measurement of long range heteronuclear coupling constants. JCH, with special emphasis on HSQMBC experiments and the spin state selective methodologies (HSQC-TOCSY-IPAP and HSQC-TOCSY-IPAP-triple editing). After that, a rationalization of the known difference between the JC4H1 and JC1H4 coupling constant transmitted mainly through the 7-bridge in norbornanone is presented in terms of the effects of hyperconjugative interactions involving the carbonyl group. Theoretical and experimental JC4H couplings were carried out for 3-endo- and 3-exo-X-2-norbornanone (X = Cl, Br, SCH3) and for exo- and endo-2- norbornanes derivatives. The hyperconjugative interactions were studied with the Natural Bond Orbital (NBO) analyses. It was observed that interactions involving the carbonyl p*C2=O and s*C2=O antibonding orbitals produce a decrease of threebond contribution for o both JC4H1 and JC1H4 couplings.However, the latter antibonding orbital also undergoes a strong sC3-C4s*C2=O interaction, which defines an additional coupling pathway for JC4H1 but not for JC1H4 .This pathway is similar to that known for homoallylic couplings, being the only difference the nature of the intermediate antibonding orbital, i.e. for JC4H1 is of s-type, while in homoallylic couplings is of p-type. / Doutorado / Quimica Organica / Doutor em Ciências

Orientador: Cláudia Regina Cavaglieri / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Educação Física / Made available in DSpace on 2018-08-27T11:34:48Z (GMT). No. of bitstreams: 1 Berton_RicardoPaesdeBarros_M.pdf: 1847286 bytes, checksum: 4830e523d7077e934302548c90bf627b (MD5) Previous issue date: 2015 / Resumo: pós a realização de uma sessão de treinamento de força, diversos metabólitos são alterados. Adicionalmente, esta resposta metabólica está envolvida em uma complexa rede metabólica que induz a alteração de uma grande quantidade de metabólitos. Desta forma, a utilização de abordagens abrangentes como a metabolômica, torna-se essencial para o entendimento do exercício de forma global. Portanto, o presente estudo teve como objetivo investigar a resposta metabólica após uma sessão de treinamento de força, por meio da metabolômica. Foram recrutados 10 indivíduos jovens do sexo masculino, que realizaram dois exercícios para membros inferiores (leg press e cadeira extensora). O protocolo constitui de quatro séries de 10 repetições, a uma intensidade de 70% de uma repetição máxima, com intervalo de 60 segundos entre as séries e entre os exercícios. As coletas sanguíneas foram realizadas nos momentos, -60 minutos, pré exercício, cinco, 15, 30 e 60 minutos após o exercício. As análises sanguíneas foram realizadas por meio da ressonância magnética nuclear. Para a análise estatística foi utilizado a análise de componentes principais e ANOVA one way para mediadas repetidas. A análise de componentes principais evidenciou uma segregação de 47.7% nos três primeiros componentes principais. Adicionalmente, foram identificados 49 metabólitos dos quais 13 metabólitos obtiveram em um e/ou mais momentos após exercício, uma alteração significante em comparação ao momento pré exercício (piruvato, lactato, succinato, 2-oxoisocaproato, alanina, 2-hidroxibutirato, 3-Hydroxi-isobutirato, hipoxantina, leucina, isoleucina, valina, lisina e ornitina). Em conclusão, é possível afirmar que a utilização da metabolômica pode ser uma ferramenta importante, uma vez que a metabolômica possibilita compreender a resposta metabólica global do exercício. Adicionalmente, possibilita a geração de novas hipóteses e descobertas / Abstract: After performing a strength training session, several metabolites are changed. Additionally, this metabolic response is involved in a complex network that induces metabolic changes in a large number of metabolites. Thus, extensive use of approaches such as metabolomics, it becomes essential to the understanding of the exercise globally. Therefore, this study aimed to investigate the metabolic response after a strength training session, through metabolomics. We recruited 10 young males, who performed two exercises for lower limbs (leg press and leg extension). The protocol was four sets of 10 repetitions, intensity of 70% of one repetition maximum, with an interval of 60 seconds between sets and between exercises. Blood samples were taken at times, -60 minutes pre exercise, five, 15, 30 and 60 minutes after exercise. Blood tests were performed using nuclear magnetic resonance. Statistical analysis was performed using principal component analysis and one-way ANOVA for repeated mediated. The principal component analysis showed a segregation of 47.7% in the first three components. Additionally, 49 metabolites were identified and 13 metabolites obtained in one and/or more times after exercise, a significant change compared to the pre exercise time (pyruvate, lactate, succinate, 2-oxoisocaproate, alanine, 2-hydroxybutyrate, 3-Hydroxy-isobutyrate, hypoxanthine, leucine, isoleucine, valine, lysine, and ornithine). In conclusion, the use of metabolomics can be an important tool, as metabolomics allows to understand the overall metabolic response to exercise. Additionally, it allows the generation of new hypotheses and discoveries / Mestrado / Atividade Fisica Adaptada / Mestre em Educação Física

Novas abordagens terapêuticas vêm sendo introduzidas para doenças musculares genéticas como distrofias musculares e miopatias congênitas, distúrbios que permanecem sem cura até o momento. Estes recentes avanços motivaram um interesse renovado e crescente por métodos não invasivos para a caracterização e monitoramento do músculo afetado, particularmente durante e após intervenções terapêuticas. Neste contexto, modelos animais são essenciais para uma melhor compreensão dos mecanismos das doenças e para testar novas terapias. Recentemente, avanços significativos na avaliação não invasiva de modelos murinos para doenças musculares genéticas foram alcançados. Entretanto, diversas linhagens de camundongos ainda não foram caracterizadas de maneira não invasiva, e ainda é necessário o desenvolvimento de métodos sensíveis para a identificação precoce de alterações sutis no músculo de camundongos afetados. A proposta desta tese é aplicar técnicas não invasivas inovadoras no estudo do músculo de modelos murinos para doenças musculares genéticas com fenótipos variados. Três modelos murinos para distrofias musculares (mdx, Largemyd, mdx/ Largemyd) e um modelo murino para miopatia congênita (KI-Dnm2R465W) foram estudados com métodos de Ressonância Magnética Nuclear (RMN). Duas linhagens distróficas (Largemyd, mdx/ Largemyd) e camundongos normais após injúria foram estudados através de micro-Tomografia Computadorizada (micro-CT). Em RMN, todas as linhagens de camundongos afetados apresentaram aumento de T2 muscular, o que foi relacionado a diversas anomalias na análise histológica, como necrose e inflamação, mas também a conjuntos de fibras em regeneração ou a fibras com citoarquitetura alterada. A combinação de RMN com análise de textura permitiu a identificação não ambígua de todas as linhagens distróficas, sendo que apenas a comparação dos valores de T2 muscular não permitiu esta diferenciação. Camundongos mdx mostraram alterações funcionais e morfológicas na rede vascular do músculo. Estudo piloto em camundongos KI-Dnm2R465W revelou tendências de comprometimento da função muscular. Por fim, imagens de micro-CT não permitiram a detecção de diferenças na composição muscular em camundongos distróficos. Este conjunto de resultados não apenas enriquece o painel de modelos murinos para doenças musculares genéticas caracterizados de maneira não invasiva, mas também demonstra um certo grau de especificidade nas anomalias observadas nas imagens, como revelado pela análise de textura. Estes resultados também mostraram que métodos não invasivos de RMN podem ser suficientemente sensíveis para identificar alterações sutis no fenótipo muscular murino, mesmo em estágios precoces. Esta tese foi desenvolvida sob acordo de co-tutela internacional entre a França e o Brasil, e compreendeu uma importante transferência de conhecimento, com os primeiros estudos não invasivos de músculo murino realizados no Brasil. / Novel therapeutic approaches are being introduced for genetic muscle diseases such as muscle dystrophies and congenital myopathies, all of them having remained without cure so far. These recent developments have motivated a renewed and augmented interest in non-invasive methods for muscle characterization and monitoring, particularly during and after therapeutic intervention. In this context, animal models are essential to better understand the disease mechanisms and to test new therapies. Recently, significant advances in the non-invasive evaluation of mouse models for genetic muscle diseases have been achieved. Nevertheless, there were still several mouse strains not characterized non-invasively, and it was necessary to develop sensitive methods to identify subtle alterations in the murine affected muscle. The purpose of this thesis was to apply non-invasive techniques in the study of murine models for genetic muscle diseases with variable phenotypes. Three mouse models for muscle dystrophy (mdx, Largemyd, mdx/ Largemyd) and one mouse model for congenital myopathy (KI-Dnm2R465W) were studied with Nuclear Magnetic Resonance (NMR) methods. Two dystrophic strains (Largemyd, mdx/ Largemyd) and normal mice after injury were studied through micro-Computed Tomography (micro-CT). On NMR, all affected mouse strains presented increased muscle T2, which could be related to variable features in the histological evaluation, including necrosis and inflammation, but also to clusters of fibers under regeneration or with altered cytoarchitecture. The combination of NMR and texture analyses allowed the unambiguous differential identification of all the dystrophic strains, although it was not feasible when comparing the muscle T2 measurements only. Mdx mice showed functional and morphological alterations of vascular network. In the KI-Dnm2R465W mice, a pilot study revealed tendencies of functional impairment. Finally, micro-CT images were unable to detect differences in muscle´s content in dystrophic mice. Altogether, these results not only increased the number of murine models for genetic muscle diseases non-invasively characterized, it also demonstrated some degree of specificity of the imaging anomalies, as revealed by texture analysis. It also showed that non-invasive NMR methods can be sensitive enough to identify subtle alterations in murine muscle phenotype, even in early stages. This thesis was developed under an international joint supervision between France and Brazil, and comprised an important transfer of technology, with the first non-invasive studies of murine muscles performed in Brazil.

There is a general lack of atomic resolution data of mobile regions of membrane proteins embedded in lipid bilayers. As an inherently complex system, few techniques can capture information about the mobile portions of an otherwise immobilized protein. The nature of crystallography and solid-state NMR relies on structural rigidity. Solution-state NMR relies on overall mobility of a protein for resolution. In the middle regime, there are few solutions to study these systems. The inward-rectifying, pH-gated potassium channel KcsA from Streptomyces lividans makes an excellent model for the development of methods to study mobile regions of membrane proteins. Of its 160 residues, more than a third are in extracellular do- mains and are not typically captured by solid-state NMR or crystallographic techniques. These pages present evidence that KcsA’s C-terminus is highly mobile and becomes increasingly dynamic when the protein is at low pH and high K+ concen- tration, where the channel is known to be active. By applying proton-detected, high-resolution magic angle spinning NMR (HR-MAS) to fractionally deuterated KcsA, previously unattainable correlations are collected and new resonance assignments are made, demonstrating the utility of the technique. The lipid environment is well known to regulate the function of KcsA in particular and membrane proteins in general. It is generally assumed that reconstituting KcsA into a synthetic phospholipid membranes provides the protein a well-defined environment. Data is presented here which shows that KcsA co-purifies with phosphoglycerol lipids from the E. coli membrane and that these molecules are 13C enriched in the course of isotopically labeling KcsA. Further, significant hydrolysis of both co- purifying and synthetic lipids occurs under ordinary experimental conditions. These findings demand that routine analysis of samples must include verification of the chemical integrity of lipids. Finally, the feasibility of applying dynamic nuclear polarization-enhanced NMR (DNP) to KcsA is investigated as a means of elucidating information about its termini. Although KcsA is known to enhance poorly by DNP, data presented here show that this is not an intrinsic property of the protein but rather an effect of the matrix in which KcsA is investigated. The use of a 15N-enriched free amino acid dissolved into buffers used for DNP is shown to be a powerful diagnostic internal standard.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第21554号 / 理博第4461号 / 新制||理||1640(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 石田 憲二, 教授 前野 悦輝, 教授 松田 祐司 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM