The theoretical part of this thesis aims to summarize the knowledge of anthropological measurements, national anthropological research, and scoliosis from the available sources of information. The research part of the thesis consists in measurements of height, weight and Adams' angle of 540 primary school pupils in Hoštka and Štětí. The resulting data are compared with national anthropological research of 2001. The measured values are further statistically analyzed and confronted with the data in scientific literature. Key words: anthropological measurements, growth spurt, BMI, scoliosis, Adams' angle

Thesis (M. Sc. (Statistics)) -- University of Limpopo, 2018 / TheEllisrasLongitudinalStudy(ELS)openedthepossibilitiesforunderstandingthegrowthvariationsamongchildreninruralSouthAfrica. Theaimofthe study was to analyse the growth spurt in height and weight of children using the ELS. This is part of the on going ELS and this study followed secondary analytical longitudinal study using data collected from November 1996 to November 2003. All children underwent a series of anthropometric measurements of height and weight according to the standard procedures recommended by the International Society for the Advancement of Kinanthropometry. The descriptive statistics was done for age, height, weight, velocity and acceleration by gender amongst rural children in Ellisras. Thelinearmixedmodelwasusedto analyse data. Based on the smallest values of AIC and BIC, the best model to fit the ELS data which was found to be the unstructured covariance structure model was chosen. The interaction between age and gender, which was significant at 5% level suggested that the relationship of age with growth varies depending on gender. There was also a significant positive linear relationship of age with distance. The onset of growth spurt for rural children in Ellisras was at 12.05 years for boys and at 12.32 years for girls, while the Senegalese boys took off earlier at 11.02 years. Ellisras rural boys and USA boys had their onset of growth spurt almost at the same age at 13 years for USA boys and 12.05 years for Ellisras rural boys. USA girls had their onset of growth spurt earlier at 11 years than Ellisras rural girls at 12.32 years. Newcastle upon Tyne adolescents reached ii their PHV at 14 and 12 years for boys and girls respectively, similarly with Ellisras rural children at 14.21 and 11.80 years for boys and girls respectively. Ellisras rural girls had their PHV at 11.80 years earlier than Ellisras rural boys at 14.21 years. Children in rural Ellisras in the ELS and their growth variations do not differ that much compared with other children across the world. Key words: Growth spurt, peak height velocity, boys, girls. / National Research Foundation (NRF)

No description available.

Neonatal Sprague-Dawley rat pups were assigned to one of five groups. Three cocaine-treated groups were injected SC with either 40, 60, or 80 mg/kg/day of cocaine from postnatal day (PND) 4 through 9. Control groups were either injected with equivalent volumes of sterile dH2O (vehicle control) or received no injections (normal control) from PND 4 through 9. This early postnatal period, corresponding to the third trimester of pregnancy in humans, is characterized as a period of rapid development within the central nervous system (CNS), generally termed the brain growth spurt. The survival rate, somatic growth, and brain development in response to the various dosages of postnatal cocaine administration were assessed. There was a dose-dependent relationship between cocaine administration and survival rate. Furthermore, significantly reduced somatic growth, assessed in terms of body weight, was found in animals given 80 mg/kg cocaine daily, as compared with controls. With respect to brain weight, no significant differences were obtained among the various doses of cocaine-treated and control animals and there was no evidence of regional vulnerability (forebrain, cerebellum, or brainstem) to the cocaine insult. Additionally, neither an effect of gender, nor the interactions of gender with various doses of cocaine treatment was found on somatic growth and brain development. Taken together, the present results suggest that the brain exhibits a greater resistance to the cocaine insults than does somatic growth. Several possible explanations regarding the somatic growth retardation are discussed.

<p>Developmental toxicology is an important part of preclinical drug toxicology as well as environmental toxicology. Assessing reproductive and developmental toxicity is especially expensive and time demanding, since at least two generations of animals are needed in the tests. In light of this there is a great need for alternative test methods in many areas of developmental toxicity testing.</p><p>The complete set of RNA transcripts in any given organism is called the transcriptome. Proteomics refers to the study of the proteins in a given organism or cell population. The work of this thesis has focused on the use of high throughput screening methods in transcriptomics and proteomics to search for molecular markers of developmental toxicity.</p><p>We have studied the global gene expression effects of the developmentally toxic substance valproic acid (VPA) using microarray technology. Several genes were found that display the same gene expression pattern <i>in vivo</i> using mouse embryos as the pattern seen <i>in vitro</i> using the embryocarcinoma cell line P19. Based on these observations, the gene Gja1 was suggested as one potential molecular marker of VPA induced developmental toxicity and potential marker of histone deacetylase (HDAC) inhibition <i>in vitro</i>. </p><p>Using 2D-DIGE technology, which measures relative protein abundances, the effect of neonatal exposure to the flame retardant PBDE-99 was studied in mouse brain (cortex, hippocampus and striatum) 24 hr after exposure. Differentially expressed proteins in the cortex and the striatum indicate that PBDE-99 may alter neurite outgrowth.</p><p>Finally, we have suggested several improvements in the use of the 2D-DIGE technology. Novel methods for normalizing data were presented, with several advantages compared to existing methods. We have presented a method named DEPPS that makes use of all identified proteins in a dataset to make comprehensive remarks about biological processes affected.</p>

Developmental toxicology is an important part of preclinical drug toxicology as well as environmental toxicology. Assessing reproductive and developmental toxicity is especially expensive and time demanding, since at least two generations of animals are needed in the tests. In light of this there is a great need for alternative test methods in many areas of developmental toxicity testing. The complete set of RNA transcripts in any given organism is called the transcriptome. Proteomics refers to the study of the proteins in a given organism or cell population. The work of this thesis has focused on the use of high throughput screening methods in transcriptomics and proteomics to search for molecular markers of developmental toxicity. We have studied the global gene expression effects of the developmentally toxic substance valproic acid (VPA) using microarray technology. Several genes were found that display the same gene expression pattern in vivo using mouse embryos as the pattern seen in vitro using the embryocarcinoma cell line P19. Based on these observations, the gene Gja1 was suggested as one potential molecular marker of VPA induced developmental toxicity and potential marker of histone deacetylase (HDAC) inhibition in vitro. Using 2D-DIGE technology, which measures relative protein abundances, the effect of neonatal exposure to the flame retardant PBDE-99 was studied in mouse brain (cortex, hippocampus and striatum) 24 hr after exposure. Differentially expressed proteins in the cortex and the striatum indicate that PBDE-99 may alter neurite outgrowth. Finally, we have suggested several improvements in the use of the 2D-DIGE technology. Novel methods for normalizing data were presented, with several advantages compared to existing methods. We have presented a method named DEPPS that makes use of all identified proteins in a dataset to make comprehensive remarks about biological processes affected.

Many cyanobacteria are reported to produce the nonprotein amino acid β-N-methylamino-L-alanine (BMAA). Cyanobacteria are extensively distributed in terrestrial and aquatic environments and recently BMAA was detected in temperate aquatic ecosystems, e.g. the Baltic Sea. Little is known about developmental effects of the mixed glutamate receptor agonist BMAA. Brain development requires an optimal level of glutamate receptor activity as the glutamatergic system modulates many vital neurodevelopmental processes. The aim of this thesis was to investigate the developmental neurotoxicity of BMAA, and its interaction with the pigment melanin. Autoradiography was utilized to determine the tissue distribution of 3H-labelled BMAA in experimental animals. Behavioral studies and histological techniques were used to study short and long-term changes in the brain following neonatal exposure to BMAA. Long-term changes in protein expression in the brain was also investigated using matrix-assisted laser desorption ionization (MALDI) imaging mass spectrometry (IMS). A notable targeting of 3H-BMAA to discrete brain regions e.g. hippocampus and striatum in mouse fetuses and neonates was determined by autoradiography. BMAA treatment of neonatal rats on postnatal days 9–10 induced acute but transient ataxia and hyperactivity. Postnatal exposure to BMAA also gave rise to reduced spatial learning and memory abilities in adulthood. Neonatal rat pups treated with BMAA at 600 mg/kg showed early neuronal cell death in the hippocampus, retrosplenial and cingulate cortices. In adulthood the CA1 region of the hippocampus displayed neuronal loss and astrogliosis. Lower doses of BMAA (50 and 200 mg/kg) caused impairments in learning and memory function without any acute or long-term morphological changes in the brain. The MALDI IMS studies, however, revealed changes in protein expression in the hippocampus and striatum suggesting more subtle effects on neurodevelopmental processes. The studies also showed that BMAA was bound and incorporated in melanin and neuromelanin, suggesting that pigmented tissues such as in the substantia nigra and eye may be sequestering BMAA. In conclusion, the findings in this thesis show that BMAA is a developmental neurotoxin in rodents. The risks posed by BMAA as a potential human neurotoxin merits further consideration, particularly if the proposed biomagnifications in the food chain are confirmed.

During the growth spurt (GS) which forms part of the mid-adolescence period of boys (13-17 years), considerable changes take place in the body composition of boys. It is therefore an unstable period where imbalances in body proportions (muscle mass, fat mass, neurological development) occur, that might have an effect on sport performance. It is also accompanied by changes in physical and motor fitness. The study firstly aimed to determine anthropometric growth changes in stature, arm span, mass, sitting height and sitting height ratio during mid-adolescence over a period of three years. The study secondly aimed to investigate the developmental changes in physical fitness (muscle strength, aerobic endurance) and motor fitness abilities (speed, agility, hand- eye coordination, explosive power) during the mid-adolescence phase of boys and finally to investigate possible relationships between anthropometric and physical and motor fitness abilities over the course of three years. A convenience sample consisting of all the grade 8 learners (n=182) of a quintile 5 high school in Potchefstroom in the North-West province of South Africa was selected to participate in a longitudinal growth research project over a three year period. Only the boys, with a mean age of 13.58 years in grade 8, of whom 95.4 % were white, 2.3% black and 2.3% colored boys, were part of the study. In 2010, 87 boys had complete measurements, while the final group in 2012 with completed follow-up measurements, were 73 boys. The physical and motor fitness components were measured according to the Australian Sport Search Program consisting of 10 tests (4 anthropometrical tests, 5 motor fitness tests, 1 physical fitness test). The cricket ball throwing test was added as an additional test. The anthropometrical measurements were made using the protocol of ISAK, while sitting height was measured according to the Canadian Sports for Life protocol. Sitting height ratio was calculated according to the formula (sitting height/stature x 100). The data was processed by “Statistica for Windows” Statsoft-computer program package. Descriptive statistics that included means (M), standard deviations (SD) and minimum and maximum values were used. A repeated measures over time analysis of variance (ANOVA) with a Bonferonni adjustment was done to analyze the differences over a period of 3 years within the group for all variables, where p<0.05 indicates a statistically significant difference. A partial correlation analysis was used to determine correlations between variables. Practical significance of correlations was determined according to Cohen’s d-value (0.1=small, 0.3=medium, 0.5=large). The results showed that during mid-adolescence in the period 13.58-14.58 years, boys grow considerably in stature, body mass, arm span and sitting height with accompanying improvement in motor and physical fitness abilities while sitting height ratio showed the greatest increase from 14.58-15.57 years. Stature, mass and arm span showed a parallel development up to 15 years after which further development leveled off, while mass increase showed no leveling off. Speed, agility, coordination and isometric-dynamic shoulder strength (basketball throw) also showed the biggest and significant improvement from 13.58-15.57 years, while explosive leg power and upper body arm and shoulder strength (vertical jump, cricket ball throw) showed the biggest and significant improvements during the period from 14.58 to 15.57 years. Significant correlations up to r=0.74; p<0.05, were found between changes in physical and motor fitness abilities and anthropometric variables, although the correlations become smaller over the 3-year period. Hand-eye coordination showed no correlation with any anthropometrical changes, while upper body strength correlated with all the anthropometrical measurements except sitting height ratio throughout the three years. It was concluded that the most accelerated growth and development took place from 13.58- 15.57 years in boys when they are in their first high school year and which falls within the mid-adolescent period (13-15 years). Furthermore, clear relationships were found between anthropometric, motor- and physical fitness variables. This knowledge of the rate of growth and motor fitness development and the relationships between these variables during the midadolescence period can provide a better understanding of changes that boys underwent during the mid-adolescent period, and can help monitoring the level of physical maturity in adolescents in order to develop training, competition and rehabilitation programs according to their developmental and not their chronological age. This cannot only prevent injuries, but also prevent early burnout in sport. / MA (Sport Science), North-West University, Potchefstroom Campus, 2014

During the growth spurt (GS) which forms part of the mid-adolescence period of boys (13-17 years), considerable changes take place in the body composition of boys. It is therefore an unstable period where imbalances in body proportions (muscle mass, fat mass, neurological development) occur, that might have an effect on sport performance. It is also accompanied by changes in physical and motor fitness. The study firstly aimed to determine anthropometric growth changes in stature, arm span, mass, sitting height and sitting height ratio during mid-adolescence over a period of three years. The study secondly aimed to investigate the developmental changes in physical fitness (muscle strength, aerobic endurance) and motor fitness abilities (speed, agility, hand- eye coordination, explosive power) during the mid-adolescence phase of boys and finally to investigate possible relationships between anthropometric and physical and motor fitness abilities over the course of three years. A convenience sample consisting of all the grade 8 learners (n=182) of a quintile 5 high school in Potchefstroom in the North-West province of South Africa was selected to participate in a longitudinal growth research project over a three year period. Only the boys, with a mean age of 13.58 years in grade 8, of whom 95.4 % were white, 2.3% black and 2.3% colored boys, were part of the study. In 2010, 87 boys had complete measurements, while the final group in 2012 with completed follow-up measurements, were 73 boys. The physical and motor fitness components were measured according to the Australian Sport Search Program consisting of 10 tests (4 anthropometrical tests, 5 motor fitness tests, 1 physical fitness test). The cricket ball throwing test was added as an additional test. The anthropometrical measurements were made using the protocol of ISAK, while sitting height was measured according to the Canadian Sports for Life protocol. Sitting height ratio was calculated according to the formula (sitting height/stature x 100). The data was processed by “Statistica for Windows” Statsoft-computer program package. Descriptive statistics that included means (M), standard deviations (SD) and minimum and maximum values were used. A repeated measures over time analysis of variance (ANOVA) with a Bonferonni adjustment was done to analyze the differences over a period of 3 years within the group for all variables, where p<0.05 indicates a statistically significant difference. A partial correlation analysis was used to determine correlations between variables. Practical significance of correlations was determined according to Cohen’s d-value (0.1=small, 0.3=medium, 0.5=large). The results showed that during mid-adolescence in the period 13.58-14.58 years, boys grow considerably in stature, body mass, arm span and sitting height with accompanying improvement in motor and physical fitness abilities while sitting height ratio showed the greatest increase from 14.58-15.57 years. Stature, mass and arm span showed a parallel development up to 15 years after which further development leveled off, while mass increase showed no leveling off. Speed, agility, coordination and isometric-dynamic shoulder strength (basketball throw) also showed the biggest and significant improvement from 13.58-15.57 years, while explosive leg power and upper body arm and shoulder strength (vertical jump, cricket ball throw) showed the biggest and significant improvements during the period from 14.58 to 15.57 years. Significant correlations up to r=0.74; p<0.05, were found between changes in physical and motor fitness abilities and anthropometric variables, although the correlations become smaller over the 3-year period. Hand-eye coordination showed no correlation with any anthropometrical changes, while upper body strength correlated with all the anthropometrical measurements except sitting height ratio throughout the three years. It was concluded that the most accelerated growth and development took place from 13.58- 15.57 years in boys when they are in their first high school year and which falls within the mid-adolescent period (13-15 years). Furthermore, clear relationships were found between anthropometric, motor- and physical fitness variables. This knowledge of the rate of growth and motor fitness development and the relationships between these variables during the midadolescence period can provide a better understanding of changes that boys underwent during the mid-adolescent period, and can help monitoring the level of physical maturity in adolescents in order to develop training, competition and rehabilitation programs according to their developmental and not their chronological age. This cannot only prevent injuries, but also prevent early burnout in sport. / MA (Sport Science), North-West University, Potchefstroom Campus, 2014

The developing brain goes through a number of developmental periods during which it displays an increased sensitivity to exogenous disturbances. On such period is the so called “Brain growth spurt” (BGS) which in humans takes place starting from the third trimester of pregnancy and throughout the first few years of life. The corresponding period in rats and mice is the first postnatal weeks. Exposure to relatively modest concentrations of the brominated flame retardant PBDE-99 during the second week of life in mice causes a more or less permanent impairment in the ability of the animals to adjust properly to environmental changes at adulthood. This “late response on early exposure” reflects the long-term consequences of disrupting the developing brain during a sensitive time period. The cellular mechanisms underlying the behavioral effects are far from clear. To address the initial damage occurring around the time of exposure, the approach used in this thesis is to use proteomics to analyze the effects of PBDE-99 on protein expression soon (24 hours) after exposure of the neonatal mouse on postnatal day (PND) 10.The thesis comprises the effects on the proteome in three distinct brain parts: cerebral cortex, striatum and the hippocampus. In addition, an in vitro model was developed and used to evaluate the PBDE-99 effects on cultured cerebral cortex cells from embryonic rat brains. Gel-based proteomics (2D-DIGE) coupled to MALDI- or ESI-MS has been used throughout for the proteomics experiments, but other techniques aimed at analyzing both proteins and mRNA have also been used to better characterize the effects. Even if the protein complements expressed by the different brain parts and separated with 2D-DIGE are seemingly similar, the effects are apparently specific for the different brain regions. In hippocampus, PBDE induces effects on proteins involved in metabolism and energy production, while the effects in striatum point towards effects on neuroplasticity. PBDE-99 changes the expression of cytoskeletal proteins in the cerebral cortex 24 hours after exposure. Interestingly, in vitro exposure of cerebral cortex cells to a PBDE-99 concentration in the same order of magnitude as in the in vivo neonatal brain also induces cytoskeletal effects, in the absence of cytotoxicity. This may suggest effects on regulatory aspects of cytoskeletal dynamics such as those involved in neurite sprouting. This thesis also addresses the problems involved in presenting proteomics data. Many of the available methods and approaches for presenting transcriptomics data are not suitable for isoform rich protein data. Modifications of existing methods and the development of a new approach (DEPPS) is also presented. Most importantly, the thesis presents the application and usefulness of proteomics as hypothesis generating techniques in neurotoxicology.