Stainless steel (SS) is the material of choice in a number of process industries ranging from food and dairy to pharmaceuticals. Adsorption phenomena on SS surfaces are of paramount importance in these industries. For example, protein adsorption constitutes a major issue in process equipment, as the associated surface fouling decreases the efficiency of the overall process and leads to an increase in operational costs because of the need for regular cleaning. In addition, the adsorption of proteins at solid–liquid interfaces is an important research field with relevance in biosensor and biomaterial applications. The primary aim of this thesis was to understand the underlying adsorption properties of selected protein onto SS surfaces and to identify the influence of specific amino acids on bio-fouling. Protein adsorption experiments were carried out on 316 grade SS sensors using a quartz crystal microbalance with dissipation (QCM-D). The proteins consisted of milk proteins (α-lactalbumin, β-lactoglobulin, α-casein, β-casein, κ-casein and bovine serum albumin), blood proteins (cytochrome-c, haemoglobin and myoglobin) and proteins of industrial and medical relevance (α-chymotrypsinogen, human recombinant insulin, lysozyme and papain). The adsorption characteristics of the test proteins were studied and an empirical correlation relating the amount of protein adsorbed to their physical properties was proposed. Adsorption onto a SS surface was followed on the QCM-D in real time and the amounts adsorbed calculated using the Sauerbrey model. In addition, the binding kinetics was modelled using different theoretical models to describe the adsorption mechanism. In all the proteins tested, the conformational change model was found to fit considerably well the adsorption data. Finally, the data collected were used to identify the physical properties of proteins that induce surface binding, with hydrophobic and aromatic amino acids having the most effect on binding. A second aspect investigated in the present work was the determination of hydration water present in the adsorbed layer. In fact, water molecules, solvated ions and other small molecules in the vicinity of the surface all play an important role in protein adsorption and often constitute a large fraction of the total measured adsorbed mass. The fraction of water present on SS surfaces along with adsorbed proteins was determined using fluorescently labelled proteins through a comparative study that included QCM-D experiments as well as fluorescent light intensity measurements. The results were similar for all proteins tested, indicating that 32-45.8% of the total mass adsorbed composed of water. One last aspect considered in this thesis was the influence of the putative adhesive amino acid 3, 4-dihydroxyphenylalanine (DOPA). DOPA residues are present in high levels in the adhesive proteins from marine mussels, hence are thought to facilitate surface attachment. The role of DOPA residues in mediating protein adhesion on SS surfaces was studied using QCM-D. Two repetitive peptide motifs extracted from the sequence of the mussel foot protein mefp-5, KGYKYYGGSS and KGYKYY, were selected for this study. The two peptides contained unmodified tyrosine (Y) residues, which were chemo-enzymatically modified to DOPA using mushroom tyrosinase. Adsorption of the two sequences on SS surfaces was tested before and after modification of tyrosine residues to DOPA. Conversion was linearly related to the incubation time of the peptide fragments with mushroom tyrosinase, Amount of DOPA formed was 70-99% of the tyrosine content in the peptides. QCM-D adsorption experiments on the DOPA-modified sequences revealed four-fold greater adhesion than for unmodified mefp-5 motifs, indicating the paramount role that DOPA has on the adsorption of peptides on 316 grade stainless steel.

Le traitement substitutif par la L-DOPA, indiqué dans la maladie de Parkinson, induit à terme des complications motrices appelées les dyskinésies induites par la L-DOPA. L'apparition des dyskinésies est due, au moins en partie, à la mise en place d'une plasticité aberrante dans le striatum, qui fait suite à des modifications transcriptionnelles induites par la L-DOPA. Une analyse du transcriptome nous a permis d'identifier le gène Nptx2, codant pour la neuropentraxine Narp, comme étant un candidat potentiellement impliqué dans l'apparition des dyskinésies. L'objectif de ce travail était d'étudier la régulation et le rôle de Narp dans l'apparition des dyskinésies, dans un modèle de souris lésée à la 6-hydroxydopamine. Nous avons montré que les dyskinésies induites par la L-DOPA sont diminuées chez des souris invalidées pour Nptx2 (Narp-KO). Par ailleurs, l'injection dans le striatum dorsal d'un adénovirus exprimant une forme dominante négative de Narp, induit une réduction importante des scores de dyskinésies. Dans le striatum, Narp est exprimé par les neurones épineux de taille moyenne et par les interneurones à parvalbumine. Après une stimulation dopaminergique, l'augmentation de l'expression de Nptx2 s'accompagne d'un enrichissement de Narp au niveau synaptique. Nos travaux montrent donc que Narp joue un rôle important dans le développement des dyskinésies et suggèrent qu'il pourrait être impliqué dans la plasticité synaptique des neurones du striatum, comme cela a été montré dans l'hippocampe. Ces résultats permettent d'ouvrir de nouvelles perspectives thérapeutiques pour retarder l'apparition de ces complications motrices chez les patients parkinsoniens. / Dopaminergic replacement therapy in Parkinson’s disease is hampered by the occurrence of L-DOPA-induced dyskinesia (LID). One major hypothesis is that LID result from L-DOPA-induced aberrant plasticity in the striatum due to modifications of the transcriptional program. Using a microarray-based approach, we identified Narp as a putative candidate implicated in LID induction. Thus, we investigated Narp involvement in LID by examining abnormal involuntary movements (AIM) development in Narp genetically-ablated mice or upon intrastriatal injection of a dominant negative form of Narp. Interestingly, the total AIM score was greatly reduced in these two models of impaired Narp expression. Hence, my results highlight Narp as an important actor in LID development. Then, I further examined Narp regulatory mechanisms in the striatum and I demonstrated that dopamine stimulation leads to increased Narp expression both at the transcriptional level and at the protein level through its accumulation within the synaptic compartment. These findings advance knowledge about mechanisms underlying dyskinesia with the hope of delaying their appearance in patients.

Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains xi, 101 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 95-99).

Thesis (Ph.D.) -- University of Texas Southwestern Medical Center at Dallas, 2006. / Not embargoed. Vita. Bibliography: 129-137.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-08-09T22:44:45Z No. of bitstreams: 1 AntonioMarcosUrbanoDeAraujo_TESE.pdf: 3225313 bytes, checksum: e25ff75db18347413666f8caf426a50e (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-08-10T22:25:30Z (GMT) No. of bitstreams: 1 AntonioMarcosUrbanoDeAraujo_TESE.pdf: 3225313 bytes, checksum: e25ff75db18347413666f8caf426a50e (MD5) / Made available in DSpace on 2016-08-10T22:25:30Z (GMT). No. of bitstreams: 1 AntonioMarcosUrbanoDeAraujo_TESE.pdf: 3225313 bytes, checksum: e25ff75db18347413666f8caf426a50e (MD5) Previous issue date: 2016-01-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Foram sintetizados neste trabalho em solu??o aquosa os seguintes compostos de coordena??o: [Ni(LDP)(H2O)2Cl2].2H2O, [Co(LDP)Cl2].3H2O, [Ni(CDP)Cl2].4H2O, [Co(CDP)Cl2].4H2O, [Ni(BDZ)2Cl2].4H2O e [Co(BDZ)2Cl2].(H2O). Esses complexos foram sintetizados por adi??o estequiom?trica do ligante nas respectivas solu??es de cloretos do metal. A precipita??o ocorreu ap?s a secagem dos solventes sob temperatura ambiente. A caracteriza??o e proposta das estruturas foram realizadas utilizando-se de m?todos convencionais de an?lise tais como: an?lise elementar (CHN), espectroscopia de absor??o na regi?o do infravermelho com transformada de Fourier (FTIR), difratometria de raios X pelo m?todo do p? e as t?cnicas termoanal?ticas TG/DTG (termogravimetria/termogravimetria derivada) e DSC (calorimetria explorat?ria diferencial). Estas t?cnicas forneceram informa??es sobre desidrata??o, modos de coordena??o, comportamento t?rmico, composi??o e estrutura dos compostos sintetizados. Com os resultados das curvas TG, p?de-se estabelecer a f?rmula geral de cada composto sintetizado. Pela an?lise dos difratogramas de raios X foi observado que quatro dos complexos sintetizados apresentam estrutura n?o cristalina que foram os complexos obtidos a partir da L-dopa e Carbidopa e para os complexos obtidos a partir do benzimidazol obteve-se estruturas cristalinas. As observa??es dos espectros na regi?o do infravermelho sugeriram uma coordena??o monodentada do ligante aos respectivos centros met?licos atrav?s do grupo amina para todos os complexos. As curvas TG-DTG e DSC forneceram informa??es e importantes sobre o comportamento e a decomposi??o t?rmica dos compostos sintetizados. Os dados de condutividade molar apontaram que as solu??es dos complexos formados se comportam como um n?o-eletr?lito, o que implica dizer que o cloro est? coordenado ao ?tomo central nos complexos. / Were synthesized in this work in the following aqueous solution coordination compounds: [Ni(LDP)(H2O)2Cl2].2H2O, [Co(LDP)Cl2].3H2O, [Ni(CDP)Cl2].4H2O, [Co(CDP)Cl2].4H2O, [Ni(BDZ)2Cl2].4H2O and [Co(BDZ)2Cl2(H2O)2]. These complexes were synthesized by stoichiometric addition of the binder in the respective metal chloride solutions. Precipitation occurred after drying the solvent at room temperature. The characterization and proposed structures were made using conventional analysis methods such as elemental analysis (CHN), absorption spectroscopy in the infrared Fourier transform spectroscopy (FTIR), X-ray diffraction by the powder method and Technical thermoanalytical TG / DTG (thermogravimetry / derivative thermogravimetry) and DSC (differential scanning calorimetry). These techniques provided information on dehydration, coordination modes, thermal performance, composition and structure of the synthesized compounds. The results of the TG curve, it was possible to establish the general formula of each compound synthesized. The analysis of X-ray diffraction was observed that four of the synthesized complex crystal structure which does not exhibit the complex was obtained from Ldopa and carbidopa and the complex obtained from benzimidazole was obtained crystal structures. The observations of the spectra in the infrared region suggested a monodentate ligand coordination to metal centers through its amine group for all complexes. The TG-DTG and DSC curves provide important information and on the behavior and thermal decomposition of the synthesized compounds. The molar conductivity data indicated that the solutions of the complexes formed behave as a nonelectrolyte, which implies that chlorine is coordinated to the central atom in the complex.

Orientador: Elizabeth Maria Aparecida Barasnevicius Quagliato / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-19T22:19:48Z (GMT). No. of bitstreams: 1 Letro_GraceHelena_D.pdf: 960474 bytes, checksum: 73209cd37ac6132633ef6ce1d577cd77 (MD5) Previous issue date: 2012 / Resumo: Estudar as complicações motoras e não motoras em um grupo de pacientes com DP em tratamento com levodopa (LD). Complicações motoras e não motoras foram avaliadas em 61 pacientes (22 mulheres e 39 homens) com DP usando LD. As escalas Unified Parkinson's Disease Rating Scale (UPDRS), estágio da doença Hoehn & Yahr e Schwab & England foram usadas para avaliar os pacientes nos períodos "on/off". Wearing-off motor e não motor foram identificados pelo Cartão Questionário de Wearing-off (QC). A depressão foi avaliada pelo Inventário de Depressão de Beck, e a percepção da qualidade de vida, pelo questionário de Qualidade de Vida na DP (PDQ-39). A média do tempo de doença foi de 7.82±3.16 anos. A idade de início dos sintomas foi de 56.70±9.38 anos, e a média de tempo de tratamento com LD foi de 5.33±3.16 anos. Flutuações motoras (FM) e discinesias foram observadas nos pacientes com DP em 78.6% e 45.9%, respectivamente. Os melhores preditores para as FM foram o tempo de tratamento com LD, UPDRS motor "on" e desconforto corporal (PDQ-39). O melhor preditor para as discinesias foi o tempo de doença. As FM foram mais bem identificadas pelo QC. Os sintomas não motores (FNM) mais frequentes foram ansiedade, alterações do humor, sensação dolorosa e dor e apareceram juntamente com as flutuações motoras. Conclusão: As flutuações motoras foram relacionadas com maior comprometimento motor, desconforto corporal e tempo de tratamento com LD. As discinesias foram correlacionadas com tempo de doença. As flutuações não motoras ocorreram simultaneamente às FM / Abstract: Study the motor and non-motor complications in a group of patients with Parkinson's disease (PD) treated with levodopa (LD). Motor and non-motor complications were assessed in 61 patients (22 women and 39 men) with PD using LD. The Unified Parkinson's Disease Rating Scale (UPDRS), Hoehn & Yahr staging and Schwab & England ADL scale were used to assess the patients "on/off" period. Motor and non-motor wearing-off effects were identified by the Wearing-off Questionnaire Card (QC). Depression was assessed by the Beck Depression Inventory and the perception of quality of life by the PD Quality of Life questionnaire (PDQ-39). The mean disease duration was 7.82±3.16 years. The mean age at onset was 56.70±9.38 years and the mean duration of levodopa (LD) treatment was 5.33±3.16 years. Motor fluctuations (MF) and dyskinesias were observed in 78.6% and 45.9%, respectively, of PD patients. The prevalence of MF was best predicted by the duration of levodopa treatment, the UPDRS "on" motor score and bodily discomfort (PDQ-39). The prevalence of dyskinesias was best predicted by disease duration. Motor symptoms were best identified by the QC. The most frequent nonmotor symptoms were anxiety, mood changes, aching and pain. Non-motor symptoms appeared along with motor symptoms. Conclusion: Motor fluctuations were related with greater motor impairment, bodily discomfort and duration of LD treatment. In addition, a correlation was found between dyskinesias and disease duration. Non-motor fluctuations occurred simultaneously with MF / Doutorado / Neurologia / Doutor em Ciências Médicas

Previous controlled studies have shown that severe daytime restriction of dietary protein improves the efficacy of L-dopa and reduces response fluctuations in some Parkinson's disease in-patients. The main purpose of the present study was to investigate the nutritional adequacy of the restricted protein diet. Other objectives were to assess the patients' acceptance of the diet and to identify the practical difficulties encountered in following the diet at home. The effect of the restricted protein diet on the subjects' response to levodopa was also examined. Subjects were 11 free-living, otherwise healthy Parkinson's disease patients who suffered from unpredictable response fluctuations to Sinemet (L-dopa containing medicine). This condition is also described as the "on-off" phenomenon. They were counselled to consume a daytime restricted protein diet for 6 weeks (mean ± s.d. protein intake before evening meal 12 ± 2 g for females and 14 ± 3 g for males). Food intake was unrestricted from dinner until bedtime, and subjects were encouraged to consume nutrient-dense foods during this period. The subjects were required to complete a series of three 6-day food records and "on-off" charts (pre-diet, diet week 2, diet week 6). The "on-off" charts indicated the daily number of hours spent in the "on" state (when medication is effective and parkinsonian symptoms are controlled) and in the "off" state (when medication is not effective and symptoms are not well controlled). Hemoglobin, plasma albumin, prealbumin and ferritin were measured before and after the 6-week diet period. Subjective evaluation questionnaires were completed by all participants and their spouses or caregivers. Results from dietary record analysis showed that the restricted protein diet was associated with significant decreases in total intakes of protein, calcium, iron, magnesium, phosphorus, niacin, riboflavin, vitamin B6 and pantothenate, in comparison to "usual" intakes. Intake of energy, carbohydrates, lipids, potassium, thiamin, folacin, and vitamins A, C and B12 did not change significantly. While on the restricted protein diet, only calcium intake was substantially less than the RNI. Biochemical measures of nutritional status were not significantly reduced. Mean body weight tended to decrease (p=.054) over the first 2 weeks and then stabilized until the end of the study period. The results of the "on-off" charts showed that three of the eleven subjects significantly increased their daily time "on" while on the restricted protein diet. Subjectively, six individuals noted an improvement in daytime mobility and indicated that they would maintain the diet for an indefinite period of time. Problems identified by the subjects included hunger prior-'to the evening meal and a lack of variety in food choices. These results show that otherwise healthy and motivated patients with Parkinson's disease can maintain an adequate intake of energy, protein, and most nutrients while on the daytime restricted protein diet. The diet appeared to be relatively well tolerated by patients who obtained a subjective benefit. It is suggested that in patients whose regular diets are marginally adequate, the restricted protein diet might compromise nutrient intakes. Counselling by a registered dietitian is recommended for all patients who undertake this type of diet. / Land and Food Systems, Faculty of / Graduate

Parkinson’s disease (PD) is a progressive neurodegenerative disorder producing a clinical syndrome of bradykinesia, rigidity and resting tremor. These motor symptoms appear due to the degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNc) and loss of dopamine in the striatum, which subsequently leads to an imbalance of the basal ganglia motor circuit. The most effective pharmacological treatment for PD is L-3,4-dihydroxyphenylalanine (L-DOPA), the immediate metabolic precursor of dopamine, which effectively restores motor function. L-DOPA is catabolised into dopamine and replaces neurotransmitter loss in PD. However, long-term L-DOPA treatment leads to abnormal involuntary movements (AIMs), such as L-DOPA-induced dyskinesia (LID), which reduces the quality of life in PD patients. Currently, there are no reliable pharmacological treatments for these motor complications. Clinical and preclinical studies have shown that development and expression of LID is linked to unregulated dopamine release and plasticity-induced changes of striatal dopaminergic and non-dopaminergic signalling pathways. The activities of these pathways can be modulated by neurotransmitter receptors of a specific classification, the G-protein-coupled receptor (GPCR) family. In turn, GPCRs are regulated by certain endogenous proteins, the regulators of G-protein signalling (RGS) proteins. Numerous RGS protein subtypes are expressed in the striatum but their roles in PD and LID remain poorly understood. Given the modulatory function of RGS proteins in the striatum, these endogenous factors may have pathophysiological roles in the expression of motor symptoms in PD and LID. The studies presented in this thesis investigated the roles of RGS proteins in the unilateral 6-hydroxydopamine (6-OHDA)-lesioned rat model of PD and LID. Rats received unilateral 6-OHDA lesions of the right medial forebrain bundle to induce severe dopamine denervation. L-DOPA/benserazide (6/15 mg/kg) was then administered once daily for at least 21 days to induce stable abnormal involuntary movements (AIMs). In Chapter 2 of this thesis, increased levels of RGS2 and RGS4 mRNA were found in the rostral striatum of the unilateral 6-OHDA-lesioned rat model of LID. Moreover, elevated levels of RGS4 mRNA were specific to sensorimotor regions and positively correlated with AIMs severity. These molecular and behavioural data suggest that RGS4 proteins are involved in the expression of LID. In Chapters 3 and 4, behavioural studies conducted in the unilateral 6-OHDA-lesioned rat model of LID showed that acute inhibition of striatal RGS4 proteins reduced the expression of AIMs and improved overall motor function. Moreover, repeated de novo treatment with RGS4 protein inhibitors, in combination with L-DOPA, attenuated the development of AIMs and reduced the overexpression of preproenkephalin-B, a molecular marker of LID. These behavioural and molecular data suggest that blockade of RGS4 proteins can reduce the induction of LID. In Chapter 5, in vivo microdialysis conducted in the unilateral 6-OHDA-lesioned rat model of LID showed that systemic administration of RGS4 protein inhibitors, in combination with L-DOPA, attenuated unregulated striatal dopamine efflux. These data suggest that RGS4 proteins may regulate specific G-protein coupled receptors, such as 5-HT1A receptors, that modulate striatal dopamine release. In conclusion, the work presented in this thesis shows that RGS4 proteins play a pathophysiological role in the expression and development of LID. These proteins could mediate regulation of key neurotransmitter receptors involved in LID, making them a potential therapeutic target for the development of future treatments.

Publicación a texto completo no autorizada por el autor / Estudia las propiedades de estabilidad termodinámica y reactividad por transferencia protónica intrínsecas (en fase gas) del neurotransmisor dopamina y su precursor L-DOPA. Para ello hace uso de la Metodología DFT (B3LYP) y “ab-initio” (métodos G3 y G4) para el estudio conformacional en especies neutras, protonadas y desprotonadas, en fase gaseosa; y la determinación experimental, mediante espectrometría de masas de triple-cuadrupolo con fuente ESI (electrospray), de la afinidad protónica y basicidad de la Dopamina y acidez de la L-DOPA en fase gaseosa, aplicando el Método Cinético Extendido de Cooks (EKCM). / Tesis

L-3,4-dihyroxyphenylalanine (L-DOPA, levodopa) is a gold standard treatment of Parkinson's disease. Lately, it has been found that some of its deuterated analogues exhibit higher potency in the treatment; thus, they could replace L-DOPA. The subject of this thesis was a study of L-DOPA and its deuterated derivatives by the means of vibrational spectroscopy (Raman, ROA, IR, and VCD) and a comparison of the experimental results to a quantum mechanical simulations of the spectra. ROA and VCD are chiroptical methods, thus they are suitable for measurement of chiral molecules amongst which L-DOPA indeed belongs. Thanks to the quantum chemistry calculations, which yielded spectra with a very good agreement with the experiment, we were able to assign experimental spectral features to individual vibrational modes of the L-DOPA. The use of chiroptical techniques (mainly ROA) enabled an assignment of an absolute configuration of double deuterated derivative of L-DOPA, α,β-D2-L-DOPA. It reviled that it occurs in a (S-α,S-β)-enantiomeric form.