Coronary artery disease (CAD), Hypertension (Ht) and Type 2 Diabetes Mellitus (T2DM) are all global health problems. This is particularly evident amongst South Asian population groups. The conventional risk factors do not fully explain the higher prevalence of these diseases among South Asians. The endothelial Nitric Oxide Synthase (eNOS) gene is responsible for the production of Nitric Oxide (NO), which may contribute to the physiology of all three disease states. Endothelial dysfunction (which is characterised by a reduction in basal NO) has been shown to be present in, or prior to all three diseases. Numerous variations exist within the eNOS gene, of these variations three have been shown to have a possible functional effect. The first is the Glu298Asp polymorphism within the exon region of the gene, resulting in an amino acid substitution of Glutamate (Glu) to Aspartate (Asp). The second, known as the T-786C polymorphism, is a thymine to cytosine mutation at position -786 in the promoter region. Finally a VNTR polymorphism in Intron 4 causes either a 4 27bp repeat or a 5 27bp repeat. It is hypothesised that these variations could have an effect on the ability of eNOS to produce NO and thus may increase the risk or contribute to the development of the diseases. Previous studies on these variants have shown conflicting results and further studies are warranted to understand and confirm the role of eNOS gene polymorphisms in cardio-metabolic diseases. There is very limited research into the distributions of these genetic variants and their interaction in diseases processes in North Indian populations. Objectives: 1. To analyse through a case control study three different polymorphisms of the eNOS gene for possible association with Coronary Artery Disease (CAD), Hypertension (Ht) and Type 2 Diabetes Mellitus (T2DM) in North Indian population groups. 2. To statistically evaluate descriptive statistics including; age, gender, smoking, dietary behaviours and lipid parameters for possible influence on disease and potential interaction with genetic polymorphisms. 3. To evaluate linkage disequilibrium between the three eNOS variants and carryout haplotype analysis to work out haplotype risk in different diseases. 4. To analyse through a case control study the deletion variant of the Angiotensin-converting enzyme (ACE) gene for possible association with Coronary Artery Disease (CAD), Hypertension (Ht) and Type 2 Diabetes Mellitus (T2DM) in North Indian population groups. 5. To determine a possible interactive effect of the eNOS polymorphisms with the ACE polymorphism. Subjects and Methods: The Glu298Asp and Intron 4 variants were genotyped using a PCR-RFLP technique, the T-786C variant was genotyped using a real time-PCR technique. The ACE deletion variant was also genotyped using a standard PCR technique. The genotyping was undertaken in a total of 457 CAD patients and 220 matched controls from Lucknow, Uttar Pradesh in North India, 319 T2DM patients and 307 matched controls from Punjab, North India and 210 Ht and 162 matched controls, also from Punjab, North India. Results: CAD: The Glu298Asp was significantly associated with CAD among smokers (TT+GT vs. GG OR=2.84 (CI: 1.61-5.0), p<0.001). The Intron 4 variant was also significantly associated with CAD in a smoking dependent manner (4aa+4ab vs. 4bb OR=0.56 (CI: 0.33-0.96). The T-786C variant showed no overall influence on CAD risk. There was also evidence for both synergistic and haplotypic effects of the eNOS gene on CAD status (haplotype G-C-4b OR=4.76 (CI: 1.43-15.78), p<0.001). The ACE genetic variant was confirmed to be a strong independent risk factor for CAD under a dominant model (OR=2.18 (CI: 1.46-3.25), p<0.001). There was no evidence for an interactive effect between the ACE deletion and any of the three eNOS variants incorporated in the current study. Ht: The Glu298Asp variant was not shown to increase Ht risk, with a reduced risk association found under a recessive model (OR=0.316 (CI:0.089-1.116)), p=0.061). The T-786C variant s role in disease remained unclear with the findings showing a non significant increased risk. The Intron 4 variant was also shown to increase Ht risk, in a non significant manner. Sufficiently powered studies would be required to clarify these possible associations. The combined analysis, using logistic regression and haplotype analysis revealed no significant associations, but there was a possible protective effect of the T-C-4b haplotype (OR=0.46 (CI: 0.21-1.01), p=0.054). The ACE gene variant was confirmed to be a strong independent risk factor for Ht under a recessive model (OR=1.81 (CI: 1.20-2.74), p=0.01). Again there was no evidence for an interactive effect between the ACE deletion and any of the three eNOS variants in hypertension. T2DM: The Glu298Asp variant was found to be associated with T2DM under a dominant model, the protective effect remained significant following adjustment for conventional risk factors and other gene variants (OR=0.407 (CI: 0.231-0.717), p=0.002). The T-786C variant showed no overall influence on T2DM risk. The Intron 4 variant also found no overall influence. Haplotype analysis found the T-T-4b was found to be significantly protective for T2DM (OR=0.41 (CI: 0.26-0.65), p=0.0002). Finally the ACE gene variant was confirmed to be a risk factor for T2DM under a dominant model (OR=2.62 (CI: 1.51-4.54), p=0.001). Overall Conclusions: To conclude, this study successfully identified the frequency of three eNOS gene variants and the ACE deletion variant in three complex diseases within north Indian populations. There is a clear role of the eNOS gene in all three diseases and consequently the genetic variants have susceptible/protective associations. The association with disease was found to be present at an individual level, in association with risk factors and at a haplotypic level. These findings warrant further studies to confirm and untangle the genetics of complex diseases and genetic risk profiles calculations which will contribute to the field of medical genomics/personalised medicare and interventions among North Indian populations.

A doença renal crônica (DRC) se associa com a hiperatividade dos sistemas nervoso simpático e renina-angiotensina-aldosterona, o que leva e aumento da pressão arterial. O exercício aeróbico pode ser utilizado para prevenir as doenças cardiovasculares associadas à DRC, em especial a hipertensão arterial porque uma única sessão de exercício aeróbico promove redução da pressão arterial após a sua execução e esse fenômeno é denominado hipotensão pós-exercício. Este efeito do exercício é mediado pela redução da atividade nervosa simpática periférica e diminuição da atividade do sistema renina-angiotensina-aldosterona. Entretanto, a presença de polimorfismos do gene da enzima conversora de angiotensina I (ECA) pode modificar a resposta aguda ao exercício aeróbico. Outro benefício descrito do exercício é seu efeito anti-inflamatório observado pela redução de marcadores inflamatórios cuja presença na DRC é marcante. Desta forma, este estudo avaliou o efeito de uma sessão de exercício aeróbico na pressão arterial, na variabilidade da frequência cardíaca e nos marcadores inflamatórios em pacientes com DRC no estágio 3, portadores de polimorfismo do gene da ECA. Para isso, 12 pacientes com DRC (estágios 3A e 3B) e 12 indivíduos saudáveis realizaram duas sessões experimentais conduzidas em ordem aleatória de exercício aeróbico (cicloergômetro, 45 min, 50% VO2pico) e repouso (repouso sentado no cicloergômetro por 45 min). Antes e após as sessões foi coletada amostra de sangue para a análise dos marcadores inflamatórios, foi registrada a variabilidade da frequência cardíaca e da pressão arterial (Finometer) e a pressão arterial. Para a análise estatística dos dados, a normalidade da distribuição foi testada pelo teste de Shapiro-Wilk e transformações matemáticas foram feitas quando necessário. Os dados foram comparados através do teste T de Student para amostras repetidas e não repetidas e pela ANOVA de dois fatores, utilizando-se como pós-teste de contraste o teste de Newman-Keuls. O exercício promoveu maior redução da PAS no grupo com DRC (-14 ± 7 vs. -4 ± 1 mmHg), na PAD o resultado foi semelhante, no qual o grupo com DRC apresentou reduções maiores que o grupo controle (-4 ± 4 vs -1 ± 1 mmHg). A FC não apresentou diferença significativa nos dois grupos pós exercício (5 ± 3 vs. 9 ± 7 bpm). As variáveis hemodinâmicas não foram diferentes entre os portadores das variações DD e II. O exercício promoveu modulação autonômica cardíaca semelhante nos dois grupos, na BFR-R e AFR-R os resultados foram semelhantes (69 ± 13 vs. 74 ± 16 un) (28 ± 20 vs. 19 ± 12 un). A variância total apresentou aumento pós exercício nos dois grupos (884 ± 837 vs. 3139 ± 2521 ms²). A modulação vasomotora (BFPAS) aumentou nos dois grupos (14 ± 4 vs. 43 ± 36) e a sensibilidade barorreflexa reduziu nos dois grupos após o exercício. Os genótipos não influenciaram as respostas neurais. Entre os marcadores inflamatórios, o TNF-alfa pós-exercício se manteve inalterado nos dois grupos estudados, mantendo apenas a diferença encontrada no pré (7,62 ± 1,21 vs. 5,59 ± 0,96). Houve redução da IL-6 nos dois grupos, porém a redução foi maior no grupo com DRC, aproximando-se dos níveis do grupo controle (1,9 ± 0,4 vs. 1,51 ± 0,45). Houve aumento da IL-10 nos dois grupos no período pós exercício, porém sem diferença significativa entre si. Não houve interação entre as variantes genotípicas e as respostas dos marcadores inflamatórios ao exercício. Concluímos que o exercício aeróbico agudo reduziu os níveis de pressão arterial de forma mais efetiva no grupo com DRC, melhorou a modulação autonômica cardíaca, reduziu as concentrações de marcadores pró-inflamatórios e aumentou as concentrações de marcadores anti-inflamatórios nos pacientes com DRC. Os polimorfismos genotípicos não influenciaram as respostas das variáveis estudadas / Chronic kidney disease (CKD) is associated with hyperactivity of the sympathetic nervous system and renin-angiotensin-aldosterone, which leads to increased blood pressure. Aerobic exercise can be used to prevent cardiovascular diseases associated with CKD, especially arterial hypertension because a single aerobic exercise session promotes blood pressure reduction after its execution and this phenomenon is called post-exercise hypotension. This effect of exercise is mediated by the reduction of peripheral sympathetic nerve activity and decreased activity of the renin-angiotensin-aldosterone system. However, the presence of angiotensin I converting enzyme (ACE) gene polymorphisms may modify the acute response to aerobic exercise. Another benefit of exercise described is its anti-inflammatory effect observed by the reduction of inflammatory markers whose presence in CKD is marked. Thus, this study evaluated the effect of an aerobic exercise session on blood pressure, heart rate variability and inflammatory markers in stage 3 CKD patients with ACE gene polymorphism. To do this, 12 patients with CKD (stages 3A and 3B) and 12 healthy subjects performed two experimental sessions conducted in a random order of aerobic exercise (cycle ergometer, 45 min, 50% VO2peak) and rest (sitting on cycle ergometer for 45 min). Before and after the sessions a blood sample was collected for the analysis of inflammatory markers, the variability of heart rate and blood pressure (Finometer) and blood pressure were recorded. For the statistical analysis of the data, the normality of the distribution was tested by the Shapiro-Wilk test and mathematical transformations were done when necessary. The data were compared by Student\'s t test for repeated and non-repeated samples and by two-way ANOVA, using the Newman-Keuls test as contrast test. The exercise promoted a greater reduction of SBP in the group with CKD (-14 ± 7 vs. -4 ± 1 mmHg), in the DBP the result was similar, in which the group with CKD presented reductions larger than the control group (-4 ± 4 vs -1 ± 1 mmHg). HR did not present a significant difference in the two post exercise groups (5 ± 3 vs. 9 ± 7 bpm). Hemodynamic variables were not different between patients with DD and II. The exercise promoted similar cardiac autonomic modulation in both groups, in the BFR-R and AFR-R the results were similar (69 ± 13 vs. 74 ± 16 un) (28 ± 20 vs. 19 ± 12 un). The total variance presented increase after exercise in both groups (884 ± 837 vs. 3139 ± 2521 ms²). Vasomotor modulation (BFPAS) increased in both groups (14 ± 4 vs. 43 ± 36) and baroreflex sensitivity decreased in both groups after exercise. Genotypes did not influence neural responses. Among the inflammatory markers, post-exercise TNF-alpha remained unchanged in the two groups, maintaining only the difference found in the pre (7.62 ± 1.21 vs. 5.59 ± 0.96). There was a reduction in IL-6 in both groups, but the reduction was greater in the CKD group, approaching the levels of the control group (1.9 ± 0.4 vs. 1.51 ± 0.45). There was an increase in IL-10 in the two groups in the post-exercise period, but without significant difference between them. There was no interaction between the genotypic variants and the responses of the inflammatory markers to exercise. We concluded that acute aerobic exercise reduced blood pressure levels more effectively in the CKD group, improved cardiac autonomic modulation, reduced proinflammatory markers concentrations, and increased concentrations of anti-inflammatory markers in CKD patients. Genotypic polymorphisms did not influence the responses of the studied variables

Na África subsaariana, as serpentes do gênero Bitis são de extrema importância, pois suas vítimas apresentam sintomas como dano local, hemorragia e uma severa hipotensão. Este trabalho identificou moléculas capazes de inibir a atividade da enzima conversora de angiotensina I (ECA) presentes no veneno de quatro serpentes do gênero Bitis. Para isto, as porções de baixa massa molecular desses 4 venenos foram fracionadas em RP-HPLC e as frações com boa inibição sobre a atividade da ECA foram analisadas por espectrometria de massas. Foram identificados 34 oligopeptídeos ricos em prolina (PRO), sendo 8 sintetizados e suas constantes de inibição (Ki) determinadas. Em testes com substratos naturais da ECA, angiotensina I e bradicinina, foi constatada a maior inibição da hidrólise da angiotensina I por quatro PROs. Todos os PROs in vivo reduziram a pressão arterial, e seis deles aumentaram a frequência cardíaca em ratos Wistar. Com isto, conclui-se que existem toxinas no veneno de serpentes do gênero Bitis responsáveis pela hipotensão. / In the sub-saharian Africa, snakes from the Bitis genus are of extreme medical importance, since its victims show symptoms as local tissue damage, hemorrhage and a severe hypotension. This work identified molecules that inhibit the angiotensin I converting enzyme (ACE) in the venom of 4 snakes from the Bitis genus. The low molecular portions of the venom of these snakes were fractionated in RP-HPLC and the fractions that efficiently inhibited the ACE activity were analyzed by mass spectrometry. 34 proline-rich oligopeptides were identified, 8 of them synthesized and had their inhibition constants (Ki) determined. In tests using natural substrates of ACE, angiotensin I and bradykinin, the angiotensin I hydrolysis were better inhibited by four PROs. In vivo tests results showed that all PROs decreased the mean arterial pressure and six of them increased the heart rate. Therefore, we can conclude that there are toxins present in the venom of Bitis capable of cause hypotension.

Low Density Parity Check (LDPC) codes are the parity check codes of long block length, whose parity check matrices have relatively few non-zero entries. To improve the performance at relatively short block lengths, LDPC codes are constructed by either pseudo-random or quasi-cyclic methods instead of random construction methods. In this thesis, pseudo-random code construction methods, the effects of closed loops and the graph connectivity on the performance of pseudo-random LDPC codes are investigated. Moreover, quasi-cyclic LDPC codes, which have encoding and storage advantages over pseudo-random LDPC codes, their construction methods and performances are reviewed. Finally, performance comparison between pseudo-random and quasi-cyclic LDPC codes is given for both regular and irregular cases.

A doença renal crônica (DRC) se associa com a hiperatividade dos sistemas nervoso simpático e renina-angiotensina-aldosterona, o que leva e aumento da pressão arterial. O exercício aeróbico pode ser utilizado para prevenir as doenças cardiovasculares associadas à DRC, em especial a hipertensão arterial porque uma única sessão de exercício aeróbico promove redução da pressão arterial após a sua execução e esse fenômeno é denominado hipotensão pós-exercício. Este efeito do exercício é mediado pela redução da atividade nervosa simpática periférica e diminuição da atividade do sistema renina-angiotensina-aldosterona. Entretanto, a presença de polimorfismos do gene da enzima conversora de angiotensina I (ECA) pode modificar a resposta aguda ao exercício aeróbico. Outro benefício descrito do exercício é seu efeito anti-inflamatório observado pela redução de marcadores inflamatórios cuja presença na DRC é marcante. Desta forma, este estudo avaliou o efeito de uma sessão de exercício aeróbico na pressão arterial, na variabilidade da frequência cardíaca e nos marcadores inflamatórios em pacientes com DRC no estágio 3, portadores de polimorfismo do gene da ECA. Para isso, 12 pacientes com DRC (estágios 3A e 3B) e 12 indivíduos saudáveis realizaram duas sessões experimentais conduzidas em ordem aleatória de exercício aeróbico (cicloergômetro, 45 min, 50% VO2pico) e repouso (repouso sentado no cicloergômetro por 45 min). Antes e após as sessões foi coletada amostra de sangue para a análise dos marcadores inflamatórios, foi registrada a variabilidade da frequência cardíaca e da pressão arterial (Finometer) e a pressão arterial. Para a análise estatística dos dados, a normalidade da distribuição foi testada pelo teste de Shapiro-Wilk e transformações matemáticas foram feitas quando necessário. Os dados foram comparados através do teste T de Student para amostras repetidas e não repetidas e pela ANOVA de dois fatores, utilizando-se como pós-teste de contraste o teste de Newman-Keuls. O exercício promoveu maior redução da PAS no grupo com DRC (-14 ± 7 vs. -4 ± 1 mmHg), na PAD o resultado foi semelhante, no qual o grupo com DRC apresentou reduções maiores que o grupo controle (-4 ± 4 vs -1 ± 1 mmHg). A FC não apresentou diferença significativa nos dois grupos pós exercício (5 ± 3 vs. 9 ± 7 bpm). As variáveis hemodinâmicas não foram diferentes entre os portadores das variações DD e II. O exercício promoveu modulação autonômica cardíaca semelhante nos dois grupos, na BFR-R e AFR-R os resultados foram semelhantes (69 ± 13 vs. 74 ± 16 un) (28 ± 20 vs. 19 ± 12 un). A variância total apresentou aumento pós exercício nos dois grupos (884 ± 837 vs. 3139 ± 2521 ms²). A modulação vasomotora (BFPAS) aumentou nos dois grupos (14 ± 4 vs. 43 ± 36) e a sensibilidade barorreflexa reduziu nos dois grupos após o exercício. Os genótipos não influenciaram as respostas neurais. Entre os marcadores inflamatórios, o TNF-alfa pós-exercício se manteve inalterado nos dois grupos estudados, mantendo apenas a diferença encontrada no pré (7,62 ± 1,21 vs. 5,59 ± 0,96). Houve redução da IL-6 nos dois grupos, porém a redução foi maior no grupo com DRC, aproximando-se dos níveis do grupo controle (1,9 ± 0,4 vs. 1,51 ± 0,45). Houve aumento da IL-10 nos dois grupos no período pós exercício, porém sem diferença significativa entre si. Não houve interação entre as variantes genotípicas e as respostas dos marcadores inflamatórios ao exercício. Concluímos que o exercício aeróbico agudo reduziu os níveis de pressão arterial de forma mais efetiva no grupo com DRC, melhorou a modulação autonômica cardíaca, reduziu as concentrações de marcadores pró-inflamatórios e aumentou as concentrações de marcadores anti-inflamatórios nos pacientes com DRC. Os polimorfismos genotípicos não influenciaram as respostas das variáveis estudadas / Chronic kidney disease (CKD) is associated with hyperactivity of the sympathetic nervous system and renin-angiotensin-aldosterone, which leads to increased blood pressure. Aerobic exercise can be used to prevent cardiovascular diseases associated with CKD, especially arterial hypertension because a single aerobic exercise session promotes blood pressure reduction after its execution and this phenomenon is called post-exercise hypotension. This effect of exercise is mediated by the reduction of peripheral sympathetic nerve activity and decreased activity of the renin-angiotensin-aldosterone system. However, the presence of angiotensin I converting enzyme (ACE) gene polymorphisms may modify the acute response to aerobic exercise. Another benefit of exercise described is its anti-inflammatory effect observed by the reduction of inflammatory markers whose presence in CKD is marked. Thus, this study evaluated the effect of an aerobic exercise session on blood pressure, heart rate variability and inflammatory markers in stage 3 CKD patients with ACE gene polymorphism. To do this, 12 patients with CKD (stages 3A and 3B) and 12 healthy subjects performed two experimental sessions conducted in a random order of aerobic exercise (cycle ergometer, 45 min, 50% VO2peak) and rest (sitting on cycle ergometer for 45 min). Before and after the sessions a blood sample was collected for the analysis of inflammatory markers, the variability of heart rate and blood pressure (Finometer) and blood pressure were recorded. For the statistical analysis of the data, the normality of the distribution was tested by the Shapiro-Wilk test and mathematical transformations were done when necessary. The data were compared by Student\'s t test for repeated and non-repeated samples and by two-way ANOVA, using the Newman-Keuls test as contrast test. The exercise promoted a greater reduction of SBP in the group with CKD (-14 ± 7 vs. -4 ± 1 mmHg), in the DBP the result was similar, in which the group with CKD presented reductions larger than the control group (-4 ± 4 vs -1 ± 1 mmHg). HR did not present a significant difference in the two post exercise groups (5 ± 3 vs. 9 ± 7 bpm). Hemodynamic variables were not different between patients with DD and II. The exercise promoted similar cardiac autonomic modulation in both groups, in the BFR-R and AFR-R the results were similar (69 ± 13 vs. 74 ± 16 un) (28 ± 20 vs. 19 ± 12 un). The total variance presented increase after exercise in both groups (884 ± 837 vs. 3139 ± 2521 ms²). Vasomotor modulation (BFPAS) increased in both groups (14 ± 4 vs. 43 ± 36) and baroreflex sensitivity decreased in both groups after exercise. Genotypes did not influence neural responses. Among the inflammatory markers, post-exercise TNF-alpha remained unchanged in the two groups, maintaining only the difference found in the pre (7.62 ± 1.21 vs. 5.59 ± 0.96). There was a reduction in IL-6 in both groups, but the reduction was greater in the CKD group, approaching the levels of the control group (1.9 ± 0.4 vs. 1.51 ± 0.45). There was an increase in IL-10 in the two groups in the post-exercise period, but without significant difference between them. There was no interaction between the genotypic variants and the responses of the inflammatory markers to exercise. We concluded that acute aerobic exercise reduced blood pressure levels more effectively in the CKD group, improved cardiac autonomic modulation, reduced proinflammatory markers concentrations, and increased concentrations of anti-inflammatory markers in CKD patients. Genotypic polymorphisms did not influence the responses of the studied variables

Angiotensin converting enzyme (ACE) catalyzes the conversion of angiotensin I (Ang I) to angiotensin II (AngII). ACE also cleaves the terminal dipeptide of vasodilating hormone bradykinin (a nonapeptide) to its inactive form. Therefore, inhibition of ACE is one of the treatments of hypertension. A number of ACE inhibitory antihypertensive drugs are known. ‘Oxidative stress’ is another disease state caused by an imbalance in the production of oxidants and antioxidants in the body. A number of studies suggest that hypertension and oxidative stress are interdependent. Therefore, ACE inhibitors having antioxidant property are considered beneficial for the treatment of hypertension. Generally, selenium compounds exhibit better antioxidant behavior than their sulfur analogues. Therefore, we have synthesized a number of selenium analogues of captopril, an ACE inhibitor used as antihypertensive drug. Similar to captopril, the selenium analogues of captopril exhibited excellent ACE inhibition property. It was observed that these compounds are very good scavengers of peroxynitrite (PN), a strong oxidizing as well as nitrating agent found in vivo. The orientation of the chiral centers in these compounds was found to be very important for their ACE inhibition behavior. A number of selenocysteine- and cysteine-containing dipeptides and tripeptides were synthesized as inhibitors of ACE. It was observed that the ACE inhibition properties of these compounds depend on various factors such as orientation of the amino functionality, substitution at the C-terminal of the inhibitor, ring size of the proline moiety or the availability of the terminal acid group in carboxylate form etc. A structure-function correlation was drawn for the ACE inhibition properties of the peptide-based selenium-or sulfur-containing compounds. These studies reveal that the antioxidant properties do not depend on the side-chain functional groups, but they depend on the availability of selenium or sulfur centers. Selenium-based compounds were found to be better antioxidants than those containing sulfur moieties. In conclusion, the present study reveals that the replacement of sulfur atom in captopril and its analogues by selenium enhances the antioxidant activity. The reaction products of lactoperoxidase (LPO)-catalyzed iodination of Ang II were separated and characterized. It was observed that LPO-catalyzed iodination of Ang II takes place preferentially at the tyrosine residue. LPO-catalyzed iodination of Ang II is inhibited by commonly used antithyroid drugs such as MMI, MTU, PTU and also by antihypertensive drug captopril. It was also observed that the monoiodo Ang I is a better substrate for ACE compared to the natural substrate Ang I. The site of nitration of Ang II by PN was also determined by MS-MS analyses. This study reveals that the nitration takes place at the tyrosine residue.

Na África subsaariana, as serpentes do gênero Bitis são de extrema importância, pois suas vítimas apresentam sintomas como dano local, hemorragia e uma severa hipotensão. Este trabalho identificou moléculas capazes de inibir a atividade da enzima conversora de angiotensina I (ECA) presentes no veneno de quatro serpentes do gênero Bitis. Para isto, as porções de baixa massa molecular desses 4 venenos foram fracionadas em RP-HPLC e as frações com boa inibição sobre a atividade da ECA foram analisadas por espectrometria de massas. Foram identificados 34 oligopeptídeos ricos em prolina (PRO), sendo 8 sintetizados e suas constantes de inibição (Ki) determinadas. Em testes com substratos naturais da ECA, angiotensina I e bradicinina, foi constatada a maior inibição da hidrólise da angiotensina I por quatro PROs. Todos os PROs in vivo reduziram a pressão arterial, e seis deles aumentaram a frequência cardíaca em ratos Wistar. Com isto, conclui-se que existem toxinas no veneno de serpentes do gênero Bitis responsáveis pela hipotensão. / In the sub-saharian Africa, snakes from the Bitis genus are of extreme medical importance, since its victims show symptoms as local tissue damage, hemorrhage and a severe hypotension. This work identified molecules that inhibit the angiotensin I converting enzyme (ACE) in the venom of 4 snakes from the Bitis genus. The low molecular portions of the venom of these snakes were fractionated in RP-HPLC and the fractions that efficiently inhibited the ACE activity were analyzed by mass spectrometry. 34 proline-rich oligopeptides were identified, 8 of them synthesized and had their inhibition constants (Ki) determined. In tests using natural substrates of ACE, angiotensin I and bradykinin, the angiotensin I hydrolysis were better inhibited by four PROs. In vivo tests results showed that all PROs decreased the mean arterial pressure and six of them increased the heart rate. Therefore, we can conclude that there are toxins present in the venom of Bitis capable of cause hypotension.

The subject of this master's thesis was to get familiar with a robot developed at the Department of Intelligent Systems of FIT VUT Brno. The goal of this work was to design and then implement hardware and software improvements of the robot so it could be capable of telepresence exploration of a narrow cave using remote control, including autonomous return back to the entrance. Also suggest possible extensions for a further improvement of the robot.

Les maladies coronariennes sont l'une des principales causes de décès dans le monde. Comment les artères coronaires sont modelées et quelles sont les molécules de signalisation qui régissent ce processus, sont des mécanismes mal compris. Dans la première partie de ma thèse, j'ai identifié le modulateur de signalisation Wnt Rspo3 comme un régulateur crucial de la formation de l'artère coronaire dans le cœur en développement. Rspo3 est spécifiquement exprimé autour des branches coronaires à des moments critiques dans leur développement. L'ablation temporelle de Rspo3 conduit à une diminution de la signalisation de β-caténine et à une réduction de la prolifération spécifique des artères. En conséquence, les branches coronariennes sont défectueuses et l'arbre artériel ne se forme pas correctement. Ces résultats identifient un mécanisme par lequel l'expression localisée de RSPO3 induit la prolifération des artères coronaires à leurs branches permettant leur formation. Le traitement des patients qui se remettent d'un infarctus du myocarde (IM) est difficile car les cardiomyocytes ont une capacité très limitée à régénérer le cœur endommagé. La voie de signalisation de l'acide rétinoïque (AR) est essentielle pour le développement cardiaque et joue un rôle protecteur dans les cœurs endommagés. Pour la deuxième partie de ma thèse, j'ai utilisé une nouvelle lignée rapportrice de l’AR et j'ai observé une réponse spécifique des cardiomyocytes. L'ablation de la signalisation de l’AR par délétion génétique des enzymes Raldh1/2/3 entraîne une augmentation de l'apoptose myocytaire à la fin du développement tardif et après l'IM. Le séquençage des ARNs des cardiomyocytes primaires révèle que le traitement à l’AR réprime l'expression de Ace1, indiquant un nouveau lien entre la signalisation AR et le système Rénine Angiotensine dans le contexte de la réparation cardiaque. / Coronary heart disease is one of the leading causes of death worldwide. How coronary arteries are remodeled and the signaling molecules that govern this process are poorly understood. For the first part of my thesis, I have identified the Wnt-signaling modulator Rspo3 as a crucial regulator of coronary artery formation in the developing heart. Rspo3 is specifically expressed around the coronary stems at critical time-points in their development. Temporal ablation of Rspo3 leads to decreased β-catenin signaling and a reduction in arterial-specific proliferation. As a result, the coronary stems are defective and the arterial tree does not form properly. These results identify a mechanism through which localized expression of RSPO3 induces proliferation of the coronary arteries at their stems and permits their formation. Treating patients recovering from myocardial infarction (MI) is difficult since cardiomyocytes have a very limited capacity to proliferate and regenerate the damaged heart. The Retinoic Acid (RA) signaling pathway is essential for cardiac development and plays a protective role in damaged hearts. For the second part of my thesis, I have utilized a novel RA reporter line and I have observed a cardiomyocyte-specific response. Ablation of RA signaling through genetic deletion of the Raldh1/2/3 enzymes leads to increased myocyte apoptosis both during late development and after MI. RNA sequencing analysis of primary cardiomyocytes reveals atRA treatment represses Ace1 expression, providing a novel link between RA signaling and the Renin Angiotensin System in the context of heart repair.

Part I. The aldosterone synthase gene (CYP11B2) polymorphism T-344C in blood pressure and left ventricular hypertrophy. BACKGROUND: Aldosterone is a key cardovascular hormone, it significantly influences volume, pressure and electrolyte balance. Aldosterone plays an important role in development of left ventricular (LV) hypertrophy and myocardial fibrosis. The aldosterone synthase gene (CYP11B2) is an important candidate gene region in essential hypertension. DESIGN AND METHODS: We assessed the influence of the T-344C polymorphism of aldosterone synthase - the rate-limiting enzyme in aldosterone biosynthesis - on the structure of the left ventricle in young normotensive men. The population included 113 normotensive mid-European Caucasian men aged 18-40 years (mean 27 +/- 5 years). We also studied the association of -344T/C polymorphism of the CYP11B2 gene with the presence and severity of hypertension in 369 individuals, of whom 213 were hypertensive patients (139 controlled hypertensive, 74 resistant hypertensive) and 156 were healthy normotensive subjects. The genotype was assessed using polymerase chain reaction with subsequent cleavage with restriction enzyme HAEIII (restriction fragment length polymorphism method) and visualization with ethidium bromide. Plasma renin activity (PRA) and plasma...