Background and aims: Hypertension is a public health problem and a major reason for hospitalisation and death. In Mozambique, low levels of detection, treatment and control have been described. However, data on target-organ damage and associated clinical conditions is lacking. We therefore aimed at characterising the clinical profile of patients with severe hypertension, describing the pattern of target organ damage and determining the outcomes at 6-month follow-up. Methods: We designed a prospective descriptive cohort study to assess adult patients with severe hypertension defined according to the Joint National Committee VII guidelines. The study was conducted from July 2015 to May 2017 at Mavalane General Hospital in Maputo-Mozambique. Patients were characterized through physical examination, laboratory profile, electrocardiography, and echocardiography, and followed for six months to assess occurrence of complications such as hypertensive heart failure, stroke, renal failure, hospital admission and death. Data were analysed using SPSS software version 20.0. The study was approved by the National Bioethics Committee for Health of Mozambique. Results: We studied 116 subjects (111 [95.7%] black; women 81 [70%]). Women were slightly younger than men (mean 57 years vs 59 years); 18 (15.5%) patients were younger than 44 years. The risk profile of the studied population included obesity (46; 42.5%); dyslipidaemia (59; 54.1%); diabetes (10; 8.6%) and smoking (8; 6.9%). At baseline, mean values for systolic and diastolic blood pressure were 192.3 ± 23.6 and 104.2 ± 15.2, respectively. The most frequent target-organ damage were left atrial enlargement in 91 (88.3%) with atrial fibrillation in 9 (7.9%); left ventricular hypertrophy in 57 (50.4%); hypertensive retinopathy in 30 (26. 3%) and renal damage in 29 (25.7%) subjects. Major events during 6-month follow-up were hospitalisations (12; 10.3%) and death (10; 8.6%). Renal damage (4; 4.2%), stroke (4; 3.4%) and heart failure (2; 1.7%) were the most common complications occurring over the follow up period. Conclusion: Severe and complicated hypertension affects young people with higher incidence of obesity, diabetes and smoking than that found in general population. High occurrence of target organ damage is found at baseline, particularly heart damage, renal lesion and stroke. On follow up, severe hypertension is associated with high number of hospitalisations and high case-fatality rate. Moreover, renal damage, stroke and hypertensive heart disease were common complications on follow up. Further research is needed to understand the determinants of these poor outcomes.

Objectives: The aim of this study was to determine the prevalence of MetS among different African populations using the new Joint Statement Criteria. Hereafter we aimed to determine whether waist or neck circumference is the best predictor of MetS risk after ethnic, gender and age-specific cut-points were developed. Lastly, we aimed to determine whether afore-mentioned cut-point can predict albumin:creatinine ratio as a marker of target organ damage. Methods: The study sample (N=409) comprised of urban African (men, N=101; women, N=99) and Caucasian (men, N=101; women, N=108) teachers from the Dr. Kenneth Kaunda Education district in the North-West Province, South Africa. Participants were aged between 25 and 65 years. Anthropometric measurements, albumin:creatinine ratio and other markers of the metabolic syndrome (MetS) (systolic and diastolic blood pressure [SBP and DBP], glucose, triglycerides [TG] and high density lipoprotein [HDL]) were determined. Results: Africans (65 and 63 % for men and women) and Caucasian men (73%) showed high prevalence of MetS; ROC analysis determined neck circumference (NC) cut-points of 39 and 35 cm for young and older African men, 32 and 35 cm for young and older African women, 40 and 41 cm for Caucasian men and 34 and 33 cm for Caucasian women. This NC cut-point can be used to determine metabolic syndrome risk in all groups, except in African women; ROC developed waist circumference (WC) cut-points were 91 cm for all African male groups, 84, 81 and 84 cm for young, older and total group of African women. Suggested WC cut-points for Caucasian men were 93 cm for the young group and 97 cm for older as well as total Caucasian male groups, while cut-points for Caucasian women were 87 cm, 79 cm and 84 cm for young, older and total Caucasian women. These WC cut-points were good measures of metabolic syndrome risk in all groups; neither cut-point of WC nor NC could increase the risk of albumin:creatinine ratio. Conclusion: African women as a group present with few MetS risk factors and glucose is associated with renal function risk in Africans; NC cut-points may be used as an additional anthropometric marker to predict the metabolic syndrome in a South African cohort, but not in African women; WC cutpoints demonstrated to be good predictors of the metabolic syndrome in the same South African cohort, especially among men; WC would seem to be the best measure of MetS risk in all African populations, although NC can also be used for this purpose in all African populations, except in African women. / Thesis (PhD (Human Movement Science))--North-West University, Potchefstroom Campus, 2012

Despite surgical innovation, the sensory and motor outcome after peripheral nerve injury is incomplete. In this thesis, the biological pathways potentially responsible for the poor functional recoveries were investigated in both the distal nerve stump/target organ, spinal motoneurons and dorsal root ganglia (DRG). The effect of delayed nerve repair was determined in a rat sciatic nerve transection model. There was a dramatic decline in the number of regenerating motoneurons and myelinated axons found in the distal nerve stumps of animals undergoing nerve repair after a delay of 3 and 6 months. RT-PCR of the distal nerve stumps showed a decline in expression of Schwann cells (SC) markers, with a progressive increase in fibrotic and proteoglycan scar markers, with increased delayed repair time. Furthermore, the yield of SC which could be isolated from the distal nerve segments progressively fell with increased delay in repair time. Consistent with the impaired distal nerve stumps the target medial gastrocnemius (MG) muscles at 3- and 6-months delayed repair were atrophied with significant declines in wet weights (61% and 27% compared with contralateral sides). The role of myogenic transcription factors, muscle specific microRNAs and musclespecific E3 ubiquitin ligases in the muscle atrophy was investigated in both gastrocnemius and soleus muscles following either crush or nerve transection injury. In the crush injury model, the soleus muscle showed significantly increased recovery in wet weight at days 14 and 28 (compared with day 7) which was not the case for the gastrocnemius muscle which continued to atrophy. There was a significantly more pronounced up-regulation of MyoD expression in the denervated soleus muscle compared with the gastrocnemius muscle. Conversely, myogenin was more markedly elevated in the gastrocnemius versus soleus muscles. The muscles also showed significantly contrasting transcriptional regulation of the microRNAs miR-1 and miR-206. MuRF1 and Atrogin-1 showed the highest levels of expression in the denervated gastrocnemius muscle. Morphological and molecular changes in spinal motoneurons were compared after L4-L5 ventral root avulsion (VRA) and distal peripheral nerve axotomy (PNA). Neuronal degeneration was indicated by decreased immunostaining for microtubule-associated protein-2 in dendrites and synaptophysin in presynaptic boutons after both VRA and PNA. Immunostaining for ED1-reactive microglia and GFAPpositive astrocytes was significantly elevated in all experimental groups. qRT-PCR analysis and Western blotting of the ventral horn from L4-L5 spinal cord segments revealed a significant upregulation of apoptotic cell death mediators including caspases-3 and -8 and a range of related death receptors following VRA. In contrast, following PNA, only caspase-8 was moderately upregulated. The mechanisms of primary sensory neuron degeneration were also investigated in the DRG following peripheral nerve axotomy, where several apoptotic pathways including those involving the endoplasmic reticulum were shown to be upregulated. In summary, these results show that the critical time point after which the outcome of regeneration becomes too poor appears to be 3-months. Both proximal and distal injury affect spinal motoneurons morphologically, but VRA induces motoneuron degeneration mediated through both intrinsic and extrinsic apoptotic pathways. Primary sensory neuron degeneration involves several different apoptotic pathways, including the endoplasmic reticulum.

Motivation Hypertension is a pertinent health problem for urban black African men (hereafter referred to as African). Sympathetic hyperactivity and a dominant α-adrenergic response pattern have both been implicated as contributing factors to their poor cardiovascular health. In addition to the deleterious effect of neurogenic hypertension on target organs, sympathetic hyperactivity may promote the accelerated progression of left ventricular hypertrophy and structural vascular disease. Aim The overarching aim of this study is to scrutinize autonomic control of the cardiovascular system in a cohort of urban African and Caucasian men during a mental challenge. Associations were investigated between potential sympatho-vagal imbalance, blood pressure and target organ damage markers to determine cardiovascular risk in ethnic male groups. Methodology The SABPA (Sympathetic activity and Ambulatory Blood Pressure in Africans) study involved the participation of 200 male teachers (99 African and 101 Caucasian) in the Kenneth Kaunda Education District of the North-West Province, South Africa. Of the participant group, HIV-infected (13 African) and clinically confirmed diabetics (1 Caucasian and 6 African men) were excluded from further analyses. Stratification was based on ethnicity and further as indicated through statistical interaction effects. Cardiovascular and autonomic responses were assessed during rest and on stressor exposure (cold pressor test and Stroop colour-word conflict test). Autonomic measures included baroreceptor sensitivity (BRS), 3-methoxy-4-hydroxy-phenylglycol (MHPG) and nitric oxide metabolite (NOx) levels. Cardiovascular variables consisted of blood pressure, cardiac output, stroke volume, total peripheral resistance, heart rate, arterial compliance and ST-segment from the 12-lead electrocardiogram. Markers of target organ damage included the Cornell product (indication of left ventricular hypertrophy) and carotid intima-media thickness as indication of structural vascular disease. Means and proportions were compared by means of standard t-test and Chi-square test, respectively. Significant differences of mean cardiovascular and autonomic measures between ethnic male groups were also determined through analysis of covariance. Uni- and multivariate regression analyses were employed to demonstrate associations between target organ damage, cardiovascular and autonomic markers. Results and conclusion of each manuscript To assess autonomic nervous system and cardiovascular function as well as target organ damage, we clearly focussed on responses where our participants were challenged. Markers of autonomic responses assessed were baroreceptor sensitivity, 3-methoxy-4-hydroxyphenylglycol and nitric oxide metabolites.  The first manuscript (Chapter 2) focused on left ventricular hypertrophy as marker of target organ damage, blood pressure and baroreceptor sensitivity as marker of autonomic function. The objective was to determine whether BRS was significantly lower in African men than in the Caucasian men. Furthermore, the possible association between attenuation of BRS and increased levels of ambulatory blood pressure as well as left ventricular hypertrophy was investigated in these population groups. Results revealed that the African men had significantly lower BRS stress responses. This attenuated BRS profile was coupled with dominant α-adrenergic response patterns, which was associated with an elevation of ambulatory blood pressure. BRS attenuation (rest and stress response) was not associated with left ventricular hypertrophy. It was concluded that lower BRS, especially during stress, may pose a significant health threat for urban African men regarding the development or promotion of α-adrenergic-driven hypertension and higher cardiovascular disease risk.  The aim of the second sub-study (Chapter 3) was to investigate possible associations between structural vascular disease (carotid intima-media thickness as marker), autonomic function (MHPG as marker) and nocturnal blood pressure in the African and Caucasian men. Results showed a higher prevalence of nocturnal hypertension in the African men, with night-time blood pressure significantly higher compared to the Caucasian men. In the African and Caucasian men, carotid intima-media thickness was linearly predicted by nocturnal systolic and diastolic blood pressure respectively. In conclusion, no associations were demonstrated between MHPG and carotid intimamedia thickness or between MHPG and nocturnal blood pressure. Elevated nocturnal blood pressure evidently seems to promote structural vascular disease in this cohort of urban African and Caucasian men.  The aim of the third manuscript presented in Chapter 4, was to investigate bioavailability of NO during mental challenge (autonomic function marker) and the possible association with structural vascular disease (carotid intima-media thickness as marker). In the African men, an attenuated NOx response was demonstrated to the Stroop colour-word conflict test. After stratification into high and low NOx response groups, in the African men with a low NOx response enhanced α-adrenergic with significant STsegment depression responses was demonstrated indicating reduced myocardial oxygen supply during mental stressor exposure. Only in the African men, a ST-segment depression was significantly associated with structural vascular disease. It was concluded that the African men demonstrated a vulnerable cardiovascular profile. In this cohort of African men, the significant association between structural vascular disease and myocardial ischemia may particularly indicate a possible higher risk for future cardiovascular events. General conclusion Through the assessment of autonomic and cardiovascular responses a possible higher cardiovascular risk was demonstrated in the African men. In this cohort sympathetic hyperactivity was evident, coupled with dominant vascular response patterns and reduced myocardial oxygen supply during mental stress exposure. Based on these findings, this population group’s risk for accelerated target organ damage, as well as for future cardiovascular events, appear significantly higher than those of the Caucasian male cohort. / Thesis (PhD (Physiology))--North-West University, Potchefstroom Campus, 2013.

Motivation Hypertension is a pertinent health problem for urban black African men (hereafter referred to as African). Sympathetic hyperactivity and a dominant α-adrenergic response pattern have both been implicated as contributing factors to their poor cardiovascular health. In addition to the deleterious effect of neurogenic hypertension on target organs, sympathetic hyperactivity may promote the accelerated progression of left ventricular hypertrophy and structural vascular disease. Aim The overarching aim of this study is to scrutinize autonomic control of the cardiovascular system in a cohort of urban African and Caucasian men during a mental challenge. Associations were investigated between potential sympatho-vagal imbalance, blood pressure and target organ damage markers to determine cardiovascular risk in ethnic male groups. Methodology The SABPA (Sympathetic activity and Ambulatory Blood Pressure in Africans) study involved the participation of 200 male teachers (99 African and 101 Caucasian) in the Kenneth Kaunda Education District of the North-West Province, South Africa. Of the participant group, HIV-infected (13 African) and clinically confirmed diabetics (1 Caucasian and 6 African men) were excluded from further analyses. Stratification was based on ethnicity and further as indicated through statistical interaction effects. Cardiovascular and autonomic responses were assessed during rest and on stressor exposure (cold pressor test and Stroop colour-word conflict test). Autonomic measures included baroreceptor sensitivity (BRS), 3-methoxy-4-hydroxy-phenylglycol (MHPG) and nitric oxide metabolite (NOx) levels. Cardiovascular variables consisted of blood pressure, cardiac output, stroke volume, total peripheral resistance, heart rate, arterial compliance and ST-segment from the 12-lead electrocardiogram. Markers of target organ damage included the Cornell product (indication of left ventricular hypertrophy) and carotid intima-media thickness as indication of structural vascular disease. Means and proportions were compared by means of standard t-test and Chi-square test, respectively. Significant differences of mean cardiovascular and autonomic measures between ethnic male groups were also determined through analysis of covariance. Uni- and multivariate regression analyses were employed to demonstrate associations between target organ damage, cardiovascular and autonomic markers. Results and conclusion of each manuscript To assess autonomic nervous system and cardiovascular function as well as target organ damage, we clearly focussed on responses where our participants were challenged. Markers of autonomic responses assessed were baroreceptor sensitivity, 3-methoxy-4-hydroxyphenylglycol and nitric oxide metabolites.  The first manuscript (Chapter 2) focused on left ventricular hypertrophy as marker of target organ damage, blood pressure and baroreceptor sensitivity as marker of autonomic function. The objective was to determine whether BRS was significantly lower in African men than in the Caucasian men. Furthermore, the possible association between attenuation of BRS and increased levels of ambulatory blood pressure as well as left ventricular hypertrophy was investigated in these population groups. Results revealed that the African men had significantly lower BRS stress responses. This attenuated BRS profile was coupled with dominant α-adrenergic response patterns, which was associated with an elevation of ambulatory blood pressure. BRS attenuation (rest and stress response) was not associated with left ventricular hypertrophy. It was concluded that lower BRS, especially during stress, may pose a significant health threat for urban African men regarding the development or promotion of α-adrenergic-driven hypertension and higher cardiovascular disease risk.  The aim of the second sub-study (Chapter 3) was to investigate possible associations between structural vascular disease (carotid intima-media thickness as marker), autonomic function (MHPG as marker) and nocturnal blood pressure in the African and Caucasian men. Results showed a higher prevalence of nocturnal hypertension in the African men, with night-time blood pressure significantly higher compared to the Caucasian men. In the African and Caucasian men, carotid intima-media thickness was linearly predicted by nocturnal systolic and diastolic blood pressure respectively. In conclusion, no associations were demonstrated between MHPG and carotid intimamedia thickness or between MHPG and nocturnal blood pressure. Elevated nocturnal blood pressure evidently seems to promote structural vascular disease in this cohort of urban African and Caucasian men.  The aim of the third manuscript presented in Chapter 4, was to investigate bioavailability of NO during mental challenge (autonomic function marker) and the possible association with structural vascular disease (carotid intima-media thickness as marker). In the African men, an attenuated NOx response was demonstrated to the Stroop colour-word conflict test. After stratification into high and low NOx response groups, in the African men with a low NOx response enhanced α-adrenergic with significant STsegment depression responses was demonstrated indicating reduced myocardial oxygen supply during mental stressor exposure. Only in the African men, a ST-segment depression was significantly associated with structural vascular disease. It was concluded that the African men demonstrated a vulnerable cardiovascular profile. In this cohort of African men, the significant association between structural vascular disease and myocardial ischemia may particularly indicate a possible higher risk for future cardiovascular events. General conclusion Through the assessment of autonomic and cardiovascular responses a possible higher cardiovascular risk was demonstrated in the African men. In this cohort sympathetic hyperactivity was evident, coupled with dominant vascular response patterns and reduced myocardial oxygen supply during mental stress exposure. Based on these findings, this population group’s risk for accelerated target organ damage, as well as for future cardiovascular events, appear significantly higher than those of the Caucasian male cohort. / Thesis (PhD (Physiology))--North-West University, Potchefstroom Campus, 2013.

MOTIVATION: The increasing prevalence of metabolic syndrome (MetS) is creating immense concern worldwide. In 2009, the International Diabetes Federation (IDF) announced the new MetS definition. MetS is diagnosed by any 3 of the following 5 indicators being present: increased waist circumference (WC), blood pressure (BP), triglycerides, and fasting glucose values, and decreased high–density lipoprotein cholesterol (HDL–C) concentrations. Psychosocial stress relating to an urban environment or acculturation greatly influences the prevalence of both MetS and target organ damage (TOD). Furthermore, in urban Africans, active coping (AC) responses have been associated more with MetS and the related cardiovascular pathology than avoidance. A further synergistic effect of MetS and AC responses was also revealed in African men, in strong association with both subclinical atherosclerosis and renal impairment. Microalbuminuria was four times higher in Africans with MetS, than in those without any MetS indicators. Furthermore, Africans, especially those utilising AC responses, present with greater carotid intima–media thickness (CIMT) than their Caucasian counterparts, although they exhibit a lipid profile that is anti–atherogenic. OBJECTIVES: The objectives were firstly to indicate and compare differences regarding AC responses in the African and Caucasian men, in accord with the prevalence of MetS indicators. Secondly, the extent to which AC responses and MetS indicators predict endothelial dysfunction was investigated. METHODOLOGY: This comparative target population study is nested in the Sympathetic Activity and Ambulatory Blood Pressure in Africans (SABPA) study, which was conducted from February until the end of May in both 2008 (Africans) and 2009 (Caucasians), avoiding seasonal changes. The Ethics Committee of the North–West University approved the study, and all volunteers gave written informed consent prior to participation. Procedures were conducted according to the institutional guidelines of the Declaration of Helsinki. The participants included 202 male teachers of which 101 were African and 101 Caucasian. Ambulatory blood pressure (BP) measurements were recorded with the Cardiotens CE120 at 30 minute intervals during the day and 60 minutes at night. Actical accelerometers determined physical activity (PA). Registered clinical psychologists supervised completion of the psychosocial questionnaires, including the Coping Strategy Indicator. Participants fasted overnight; after the last BP recording, disconnection of the Cardiotens CE120 and Actical followed. A fasting 8 hour overnight collected urine sample was obtained from each participant. Anthropometric measurements followed, after which a registered nurse commenced blood sampling. The SonoSite Micromaxx was used for the scanning of CIMT. MetS indicators (glucose, triglyceride, and HDL–C), together with gamma glutamyl transferase, cotinine, and ultrahigh–sensitivity C–reactive protein (hs–CRP), were analyzed with Konelab 20i. The albumin–to–creatinine ratio and CIMT determined TOD. Participants were stratified according to ethnicity and median splits of AC response scores (high AC and low AC). Diabetic medication users (n= 8), and participants with renal impairment (n= 2) or HIV positive (n= 13), were excluded from analyses. 2×2 ANCOVA’s determined significant interactions for ethnicity and AC. Partial correlations between MetS indicators and TOD were performed within each ethnic and AC group, independent of age, alcohol consumption and PA. Regression analyses were performed for four models, firstly with microalbuminuria and secondly with CIMT as dependent variables. Significant values were noted as p 0.05, r 0.35, and adjusted R2 0.25. RESULTS: Caucasian men were physically more active than African men, whilst BP, alcohol consumption and hs–CRP levels were significantly higher in African men. Psychological variables revealed higher avoidance scores in Caucasian men and higher social support scores in African men. More MetS indicators exceeded the IDF cut–off points in high AC African men (14.71%) than in their Caucasian counterparts (3.33%). Furthermore, more MetS indicators predicted endothelial dysfunction in African men, especially the high AC responders. CONCLUSION: The following hypotheses were accepted: high AC responses in urban African men were associated with a higher prevalence of MetS indicators than in their Caucasian counterparts, while MetS indicators were associated with a marker of TOD in urban high AC African men, but not in their Caucasian counterparts. / Thesis (M.Sc. (Physiology))--North-West University, Potchefstroom Campus, 2011.

MOTIVATION: The increasing prevalence of metabolic syndrome (MetS) is creating immense concern worldwide. In 2009, the International Diabetes Federation (IDF) announced the new MetS definition. MetS is diagnosed by any 3 of the following 5 indicators being present: increased waist circumference (WC), blood pressure (BP), triglycerides, and fasting glucose values, and decreased high–density lipoprotein cholesterol (HDL–C) concentrations. Psychosocial stress relating to an urban environment or acculturation greatly influences the prevalence of both MetS and target organ damage (TOD). Furthermore, in urban Africans, active coping (AC) responses have been associated more with MetS and the related cardiovascular pathology than avoidance. A further synergistic effect of MetS and AC responses was also revealed in African men, in strong association with both subclinical atherosclerosis and renal impairment. Microalbuminuria was four times higher in Africans with MetS, than in those without any MetS indicators. Furthermore, Africans, especially those utilising AC responses, present with greater carotid intima–media thickness (CIMT) than their Caucasian counterparts, although they exhibit a lipid profile that is anti–atherogenic. OBJECTIVES: The objectives were firstly to indicate and compare differences regarding AC responses in the African and Caucasian men, in accord with the prevalence of MetS indicators. Secondly, the extent to which AC responses and MetS indicators predict endothelial dysfunction was investigated. METHODOLOGY: This comparative target population study is nested in the Sympathetic Activity and Ambulatory Blood Pressure in Africans (SABPA) study, which was conducted from February until the end of May in both 2008 (Africans) and 2009 (Caucasians), avoiding seasonal changes. The Ethics Committee of the North–West University approved the study, and all volunteers gave written informed consent prior to participation. Procedures were conducted according to the institutional guidelines of the Declaration of Helsinki. The participants included 202 male teachers of which 101 were African and 101 Caucasian. Ambulatory blood pressure (BP) measurements were recorded with the Cardiotens CE120 at 30 minute intervals during the day and 60 minutes at night. Actical accelerometers determined physical activity (PA). Registered clinical psychologists supervised completion of the psychosocial questionnaires, including the Coping Strategy Indicator. Participants fasted overnight; after the last BP recording, disconnection of the Cardiotens CE120 and Actical followed. A fasting 8 hour overnight collected urine sample was obtained from each participant. Anthropometric measurements followed, after which a registered nurse commenced blood sampling. The SonoSite Micromaxx was used for the scanning of CIMT. MetS indicators (glucose, triglyceride, and HDL–C), together with gamma glutamyl transferase, cotinine, and ultrahigh–sensitivity C–reactive protein (hs–CRP), were analyzed with Konelab 20i. The albumin–to–creatinine ratio and CIMT determined TOD. Participants were stratified according to ethnicity and median splits of AC response scores (high AC and low AC). Diabetic medication users (n= 8), and participants with renal impairment (n= 2) or HIV positive (n= 13), were excluded from analyses. 2×2 ANCOVA’s determined significant interactions for ethnicity and AC. Partial correlations between MetS indicators and TOD were performed within each ethnic and AC group, independent of age, alcohol consumption and PA. Regression analyses were performed for four models, firstly with microalbuminuria and secondly with CIMT as dependent variables. Significant values were noted as p 0.05, r 0.35, and adjusted R2 0.25. RESULTS: Caucasian men were physically more active than African men, whilst BP, alcohol consumption and hs–CRP levels were significantly higher in African men. Psychological variables revealed higher avoidance scores in Caucasian men and higher social support scores in African men. More MetS indicators exceeded the IDF cut–off points in high AC African men (14.71%) than in their Caucasian counterparts (3.33%). Furthermore, more MetS indicators predicted endothelial dysfunction in African men, especially the high AC responders. CONCLUSION: The following hypotheses were accepted: high AC responses in urban African men were associated with a higher prevalence of MetS indicators than in their Caucasian counterparts, while MetS indicators were associated with a marker of TOD in urban high AC African men, but not in their Caucasian counterparts. / Thesis (M.Sc. (Physiology))--North-West University, Potchefstroom Campus, 2011.

Objectives: The aim of this study was to determine the prevalence of MetS among different African populations using the new Joint Statement Criteria. Hereafter we aimed to determine whether waist or neck circumference is the best predictor of MetS risk after ethnic, gender and age-specific cut-points were developed. Lastly, we aimed to determine whether afore-mentioned cut-point can predict albumin:creatinine ratio as a marker of target organ damage. Methods: The study sample (N=409) comprised of urban African (men, N=101; women, N=99) and Caucasian (men, N=101; women, N=108) teachers from the Dr. Kenneth Kaunda Education district in the North-West Province, South Africa. Participants were aged between 25 and 65 years. Anthropometric measurements, albumin:creatinine ratio and other markers of the metabolic syndrome (MetS) (systolic and diastolic blood pressure [SBP and DBP], glucose, triglycerides [TG] and high density lipoprotein [HDL]) were determined. Results: Africans (65 and 63 % for men and women) and Caucasian men (73%) showed high prevalence of MetS; ROC analysis determined neck circumference (NC) cut-points of 39 and 35 cm for young and older African men, 32 and 35 cm for young and older African women, 40 and 41 cm for Caucasian men and 34 and 33 cm for Caucasian women. This NC cut-point can be used to determine metabolic syndrome risk in all groups, except in African women; ROC developed waist circumference (WC) cut-points were 91 cm for all African male groups, 84, 81 and 84 cm for young, older and total group of African women. Suggested WC cut-points for Caucasian men were 93 cm for the young group and 97 cm for older as well as total Caucasian male groups, while cut-points for Caucasian women were 87 cm, 79 cm and 84 cm for young, older and total Caucasian women. These WC cut-points were good measures of metabolic syndrome risk in all groups; neither cut-point of WC nor NC could increase the risk of albumin:creatinine ratio. Conclusion: African women as a group present with few MetS risk factors and glucose is associated with renal function risk in Africans; NC cut-points may be used as an additional anthropometric marker to predict the metabolic syndrome in a South African cohort, but not in African women; WC cutpoints demonstrated to be good predictors of the metabolic syndrome in the same South African cohort, especially among men; WC would seem to be the best measure of MetS risk in all African populations, although NC can also be used for this purpose in all African populations, except in African women. / Thesis (PhD (Human Movement Science))--North-West University, Potchefstroom Campus, 2012

Orientador: Heitor Moreno Junior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-22T22:35:29Z (GMT). No. of bitstreams: 1 Sabbatini_AndreaRodrigues_M.pdf: 734821 bytes, checksum: 425c8617b929aa51eafad2759c8957a5 (MD5) Previous issue date: 2013 / Resumo: Hipertensão arterial resistente (HAR) é uma condição clínica que inclui pacientes com HAR controlada (HARC) e HAR não controlada (HARNC). Pacientes resistentes frequentemente apresentam alterações nos níveis de adipocinas e lesões em órgãos-alvo (LOA) como rigidez arterial, hipertrofia ventricular esquerda (HVE) e microalbuminúria (MA). Resistina, leptina e adiponectina podem ter efeitos no controle da pressão arterial (PA), contudo, não se sabe se os níveis de adipocinas e marcadores de LOA estão associados nos subgrupos de HAR. Objetivo: Avaliar a relação entre os níveis de adipocinas e rigidez arterial, HVE e MA em ambos os subgrupos. Métodos: Foram avaliados em HARC (n=38) e HARNC (n=51) o IMC, PA de consultório e MAPA, níveis plasmáticos de adiponectina, leptina e resistina (ELISA), velocidade de onda de pulso (VOP), MA e ecocardiograma. Resultados: Níveis de leptina e resistina estavam aumentados (30,4±16,8 ng/mL; p = 0,004 e 11,3±4,0 pg/mL; p = 0,007 respectivamente) em HARNC, enquanto os níveis de adiponectina diminuídos (4,7± 2,6 ug/mL; p < 0,001). Rigidez arterial, HVE e MA estavam aumentados (11,3±2,5 m/s; p < 0,001; 153,6±35,1 g/m2; p < 0,001; e 92,4±97,0 mg/g; p < 0,001 respectivamente) no subgrupo com HARNC. Neste subgrupo encontramos correlação inversa entre adiponectina e VOP (r = -0,42, p < 0,01) bem como com MA (r = -0,48, p < 0,01). Houve correlação positiva entre leptina e VOP (r = 0,37, p = 0,02) somente no subgrupo HARNC e a resistina não se correlacionou com marcadores de LOA em ambos os subgrupos. Conclusão: Hipoadiponectinemia está associada à presença de maior rigidez arterial e MA somente em pacientes HARNC. Níveis elevados de leptina estão associados somente com rigidez arterial neste mesmo subgrupo. Essas adipocinas podem influenciar a resistência a terapia anti-hipertensiva, contribuindo para a dificuldade de controle pressórico neste subgrupo de HAR / Abstract: Resistant hypertension (RHTN) is a clinical condition that includes patients with controlled RHTN (CRHTN) and uncontrolled RHTN (UCRHTN). Patients with RHTN often have changes in adipokines levels and target organ damage (TOD) as arterial stiffness, left ventricular hypertrophy (LVH) and microalbuminuria (MA). Resistin, leptin and adiponectin may have effects on blood pressure (BP) control, however, it is unknown whether adipokines levels and markers TOD are associated in subgroups of RHTN. Objective: Was to assess the relationship between adipokines levels and arterial stiffness, LVH and MA in both subgroups. Methods: Were evaluated in URHTN (n=38) and UCRHTN (n=51) patients the BMI, ABPM, adiponectin, leptin and resistin plasma concentrations (ELISA), PWV, MA and echocardiogram. Results: Leptin and resistin levels were increased (30.4 ± 16.8 ng/ml, p = 0.004 and 11.3 ± 4.0 pg/mL, p = 0.007 respectively) in UCRHTN, while decreased adiponectin levels (4.7 ± 2.6 ug/ml, p < 0.001) were shown in this same subgroup. Arterial stiffness, LVH and MA were increased (11.3 ± 2.5 m/s, p < 0.001, 153.6 ± 35.1 g/m2, p < 0.001, and 92.4 ± 97.0 mg/g, p < 0.001 respectively) in UCRHTN subgroup. UCRHTN, but not in CRHTN showed an inverse correlation between adiponectin and PWV (r = -0.42, p < 0.01) as well as MA (r = -0.48, p < 0.01). Indeed, leptin was positively correlated with PWV (r = 0.37, p = 0.02) only in UCRHTN subgroup and resistin showed no correlation with TOD in both subgroups. Conclusion: Adiponectin is associated with arterial stiffness and renal injury in the UCRHTN patients, while leptin is associated with arterial stiffness in the same subgroup. These adipokines may influence resistance to antihypertensive therapy, and, thus, contribute to the difficulty of BP control in this subgroup of hypertensive patients / Mestrado / Farmacologia / Mestra em Farmacologia

Hypertension is a major risk factor for cardiovascular (CV) disease, and patients with primary aldosteronism (PA) - the most common endocrine cause of hypertension - have a higher incidence of CV complications. The aim of this study was to evaluate the incidence of metabolic differences and organ complications - kidney, heart and blood vessels damage in patients with essential hypertension (EH), PA and its most common forms - idiopathic hyperaldosteronism (IHA) and aldosterone-producing adenoma (APA). We found a higher incidence of metabolic syndrome and a higher incidence of metabolic abnormalities in IHA compared to APA - higher prevalence of metabolic syndrome, higher levels of triglycerides and lower levels of HDL cholesterol and thereby a higher cardiometabolic risk. Metabolic profile of patients with IHA is similar to EH in contrast to APA. Arterial stiffness was expressed as pulse wave velocity (PWV), in central arteries as carotid-femoral PWV and at peripheral level as femoral-ankle PWV. Patients with PA with comparable levels of blood pressure (BP) have higher stiffness of central elastic and peripheral muscular arteries than patients with EH. The main predictor of impaired peripheral arterial stiffness is the plasma aldosterone level. Patients with IHA have higher central arterial...