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Effects of chronic methamphetamine exposure during early or late phase development in normal and social isolation reared rats / Laetitia Strauss.Strauss, Laetitia January 2012 (has links)
Methamphetamine (MA) abuse is a fast growing drug problem, and is the second most widely abused drug world-wide. MA abuse has been linked to the development of symptoms indistinguishable from schizophrenia, referred to as MA psychosis. MA abusing individuals, who most often comprise adolescents and young adults, are 11 times more likely than the general population to develop psychosis. Of further concern is that in utero exposure to MA is also a growing problem, with more women addicts choosing MA as their primary drug. This has significant implications for the neurodevelopment of the child, with subsequent behavioural deficits later in life. Epidemiological studies suggests that in utero or early life MA exposure places a vulnerable individual at greater risk for developing schizophrenia, although this has never been formerly studied either at clinical or pre-clinical level. Animal models of early life adversity, such as post-weaning social isolation rearing (SIR), can assist in understanding the underlying mechanisms in MA abuse and vulnerability to develop MA psychosis.
The aim of the current study was to investigate the long term effects of either prenatal (in utero) or early postnatal administration of MA on the development of schizophrenia-like behavioural and neurochemical abnormalities later in life.
In the in utero study, pregnant female Wistar rats received either saline (Sal) or MA 5 mg/kg/day for 16 days by subcutaneous (s.c.) injection , starting on prenatal day 13 (PreND-13) up to postnatal day 2 (PostND02). Male offspring were selected for the study. On PostND 21, the animals were weaned and reared under group or isolation reared conditions for 8 weeks. In the early postnatal study, adult male Wistar rats were divided into group reared and SIR conditions from PostND21. Either group received an escalating dose of MA twice a day (0.2 mg/kg – 6 mg/kg s.c.) or Sal for 16 days, from PostND35 to PostND50. Both in utero and early postnatal groups were then subjected to various behavioural tests on PostND78, including assessment of social interaction (SI) and prepulse inhibition (PPI) of acoustic startle. Following behavioural testing, rats were sacrificed and brains snap frozen for later analysis of cortico-striatal monoamine concentrations, superoxide dismutase activity and lipid peroxidation.
In the prenatally exposed group no differences in %PPI was observed, although group reared animals receiving MA and SIR animals receiving Sal or MA showed a decrease in social interactive behaviours, including approaching, time together and anogenital sniffing. SIR animals receiving Sal or MA also showed a decrease in rearing. Regarding self-directed behaviours, group reared animals receiving MA and SIR animals receiving Sal or MA showed an increase in self-grooming. Although some disturbances in regional brain monoamines were observed in the frontal cortex and striatum across the groups, this did not reach significance. A significant increase in malondialdehyde was observed in the striatum in group reared animals receiving MA as well as SIR animals receiving Sal or MA, indicating cell damage, possibly of redox origin.
In the early postnatal study, %PPI was significantly reduced in group reared animals receiving MA as well as in SIR animals receiving Sal or MA. Group reared animals receiving MA and SIR animals receiving Sal or MA showed a decrease in social interactive behaviours, including rearing, approaching, time together and anogenital sniffing. Regarding self-directed behaviours and locomotor activity, self-grooming and squares crossed was significantly increased in group reared animals receiving MA and SIR animals receiving Sal or MA. A significant increase in DA was evident in the frontal cortex of SIR and grouped housed animals receiving MA. DA in the MA + SIR combination was elevated but not significantly so. None of the treatments affected striatal monoamine levels. In the group reared animals receiving MA as well as the SIR animals receiving Sal or MA, a significant decrease in SOD activity was observed in the frontal cortex, indicating the presence of oxidative stress in this brain region. None of the parameters indicated an additive effect in MA + SIR treated animals.
In conclusion, prenatal exposure to MA led to some evidence of late-life behavioural and neurochemical abnormalities akin to schizophrenia, confirming its penchant for psychotogenic effects. However, chronic postnatal MA exposure was more emphatic, being as effective as SIR, a neurodevelopmental model of schizophrenia, in inducing deficits in the above-mentioned behavioural and neurochemical parameters. Thus, early adolescent abuse of MA is a significant risk factor for the later development of schizophrenia or psychosis. However, the risk appeared not to be exacerbated in a population at risk, i.e. in SIR animals. / Thesis (MSc (Pharmacology))--North-West University, Potchefstroom Campus, 2013.
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Effects of chronic methamphetamine exposure during early or late phase development in normal and social isolation reared rats / Laetitia Strauss.Strauss, Laetitia January 2012 (has links)
Methamphetamine (MA) abuse is a fast growing drug problem, and is the second most widely abused drug world-wide. MA abuse has been linked to the development of symptoms indistinguishable from schizophrenia, referred to as MA psychosis. MA abusing individuals, who most often comprise adolescents and young adults, are 11 times more likely than the general population to develop psychosis. Of further concern is that in utero exposure to MA is also a growing problem, with more women addicts choosing MA as their primary drug. This has significant implications for the neurodevelopment of the child, with subsequent behavioural deficits later in life. Epidemiological studies suggests that in utero or early life MA exposure places a vulnerable individual at greater risk for developing schizophrenia, although this has never been formerly studied either at clinical or pre-clinical level. Animal models of early life adversity, such as post-weaning social isolation rearing (SIR), can assist in understanding the underlying mechanisms in MA abuse and vulnerability to develop MA psychosis.
The aim of the current study was to investigate the long term effects of either prenatal (in utero) or early postnatal administration of MA on the development of schizophrenia-like behavioural and neurochemical abnormalities later in life.
In the in utero study, pregnant female Wistar rats received either saline (Sal) or MA 5 mg/kg/day for 16 days by subcutaneous (s.c.) injection , starting on prenatal day 13 (PreND-13) up to postnatal day 2 (PostND02). Male offspring were selected for the study. On PostND 21, the animals were weaned and reared under group or isolation reared conditions for 8 weeks. In the early postnatal study, adult male Wistar rats were divided into group reared and SIR conditions from PostND21. Either group received an escalating dose of MA twice a day (0.2 mg/kg – 6 mg/kg s.c.) or Sal for 16 days, from PostND35 to PostND50. Both in utero and early postnatal groups were then subjected to various behavioural tests on PostND78, including assessment of social interaction (SI) and prepulse inhibition (PPI) of acoustic startle. Following behavioural testing, rats were sacrificed and brains snap frozen for later analysis of cortico-striatal monoamine concentrations, superoxide dismutase activity and lipid peroxidation.
In the prenatally exposed group no differences in %PPI was observed, although group reared animals receiving MA and SIR animals receiving Sal or MA showed a decrease in social interactive behaviours, including approaching, time together and anogenital sniffing. SIR animals receiving Sal or MA also showed a decrease in rearing. Regarding self-directed behaviours, group reared animals receiving MA and SIR animals receiving Sal or MA showed an increase in self-grooming. Although some disturbances in regional brain monoamines were observed in the frontal cortex and striatum across the groups, this did not reach significance. A significant increase in malondialdehyde was observed in the striatum in group reared animals receiving MA as well as SIR animals receiving Sal or MA, indicating cell damage, possibly of redox origin.
In the early postnatal study, %PPI was significantly reduced in group reared animals receiving MA as well as in SIR animals receiving Sal or MA. Group reared animals receiving MA and SIR animals receiving Sal or MA showed a decrease in social interactive behaviours, including rearing, approaching, time together and anogenital sniffing. Regarding self-directed behaviours and locomotor activity, self-grooming and squares crossed was significantly increased in group reared animals receiving MA and SIR animals receiving Sal or MA. A significant increase in DA was evident in the frontal cortex of SIR and grouped housed animals receiving MA. DA in the MA + SIR combination was elevated but not significantly so. None of the treatments affected striatal monoamine levels. In the group reared animals receiving MA as well as the SIR animals receiving Sal or MA, a significant decrease in SOD activity was observed in the frontal cortex, indicating the presence of oxidative stress in this brain region. None of the parameters indicated an additive effect in MA + SIR treated animals.
In conclusion, prenatal exposure to MA led to some evidence of late-life behavioural and neurochemical abnormalities akin to schizophrenia, confirming its penchant for psychotogenic effects. However, chronic postnatal MA exposure was more emphatic, being as effective as SIR, a neurodevelopmental model of schizophrenia, in inducing deficits in the above-mentioned behavioural and neurochemical parameters. Thus, early adolescent abuse of MA is a significant risk factor for the later development of schizophrenia or psychosis. However, the risk appeared not to be exacerbated in a population at risk, i.e. in SIR animals. / Thesis (MSc (Pharmacology))--North-West University, Potchefstroom Campus, 2013.
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An exploration of the sense of community of older persons in an economically deprived and culturally diverse residential care facility / van der Walt, E.Van der Walt, Elmarie Muriel January 2011 (has links)
The sharp increase in the number of older persons (60 years and older) is a distinctive demographic feature of the 20th century. Ageing populations and the unique challenges they pose have obliged countries worldwide to reflect on the problems relating to older persons. In 2002 the United Nations convened the Second World Assembly on Ageing at which the Madrid International Plan of Action on Ageing (MIPAA) was drafted and adopted. This plan sought to meet the challenges associated with ageing populations.
In South Africa the elderly population is also increasing dramatically. The fact that older persons are starting to constitute a proportionally larger segment of the total population while they are, at the same time, amongst the poorest people in the country and dependent on others for support and care holds serious implications for South Africa. In post–apartheid South Africa (after 1994) residential care facilities were opened to all South Africans regardless of race or colour. Apart from dealing with diversity, residential care facilities have to manage the long–term care needs of older persons and their lack of the financial or human resources to sustain themselves. Against this background the South African government promulgated legislation in line with the recommendations of the MIPAA. The legislation seeks to lighten the burden placed on residential care facilities while, at the same time, emphasising the importance of enhancing the well–being of older persons.
Despite the legislation and the policy frameworks, the circumstances in most residential care facilities in South Africa are challenging and call for action and psychosocial interventions. Given that racial segregation still exists in residential care facilities and the importance of the relational well–being of older persons, it was decided to explore the sense of community of older persons in South Africa who reside in a diverse and economically challenged residential care facility. A purposive sample was drawn of the male and female, and black and white older persons living in the facility. The study used the Mmogo–methodTM, interviews, focus groups, observations and reflective notes to collect qualitative data from the research participants. A possible limitation of the study is that some participants – being older persons – might experience some degree of being cognitively challenged or might struggle to express themselves. To counter this limitation and to ensure the trustworthiness of the findings, a variety of data collection methods were used in order to be able to cross–check the information gathered. Apart from this, specific data collection methods were used that make provision for cognitively challenged older persons.
As the study involved older persons as a vulnerable group, special attention was paid to ethical considerations. Ethical approval was granted by the Ethics Committee of the North–West University, Potchefstroom Campus, as part of a larger project, being: “An exploration of enabling contexts (05K14).”
The main finding of the study is the low sense of community that the older persons in this particular residential care facility experience. This is supplemented by two themes that emerged throughout the study, being the lack of social interaction between the residents and the residents' need to have a sense of purpose. The occurrence of these two themes is supported by findings in community psychology and sense of community theories, and some of the findings of the study are consistent with findings reported in the literature. The study concludes with recommendations on how the residents' sense of community could be enhanced. / Thesis (M.A. (Research Psychology))--North-West University, Potchefstroom Campus, 2012.
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An exploration of the sense of community of older persons in an economically deprived and culturally diverse residential care facility / van der Walt, E.Van der Walt, Elmarie Muriel January 2011 (has links)
The sharp increase in the number of older persons (60 years and older) is a distinctive demographic feature of the 20th century. Ageing populations and the unique challenges they pose have obliged countries worldwide to reflect on the problems relating to older persons. In 2002 the United Nations convened the Second World Assembly on Ageing at which the Madrid International Plan of Action on Ageing (MIPAA) was drafted and adopted. This plan sought to meet the challenges associated with ageing populations.
In South Africa the elderly population is also increasing dramatically. The fact that older persons are starting to constitute a proportionally larger segment of the total population while they are, at the same time, amongst the poorest people in the country and dependent on others for support and care holds serious implications for South Africa. In post–apartheid South Africa (after 1994) residential care facilities were opened to all South Africans regardless of race or colour. Apart from dealing with diversity, residential care facilities have to manage the long–term care needs of older persons and their lack of the financial or human resources to sustain themselves. Against this background the South African government promulgated legislation in line with the recommendations of the MIPAA. The legislation seeks to lighten the burden placed on residential care facilities while, at the same time, emphasising the importance of enhancing the well–being of older persons.
Despite the legislation and the policy frameworks, the circumstances in most residential care facilities in South Africa are challenging and call for action and psychosocial interventions. Given that racial segregation still exists in residential care facilities and the importance of the relational well–being of older persons, it was decided to explore the sense of community of older persons in South Africa who reside in a diverse and economically challenged residential care facility. A purposive sample was drawn of the male and female, and black and white older persons living in the facility. The study used the Mmogo–methodTM, interviews, focus groups, observations and reflective notes to collect qualitative data from the research participants. A possible limitation of the study is that some participants – being older persons – might experience some degree of being cognitively challenged or might struggle to express themselves. To counter this limitation and to ensure the trustworthiness of the findings, a variety of data collection methods were used in order to be able to cross–check the information gathered. Apart from this, specific data collection methods were used that make provision for cognitively challenged older persons.
As the study involved older persons as a vulnerable group, special attention was paid to ethical considerations. Ethical approval was granted by the Ethics Committee of the North–West University, Potchefstroom Campus, as part of a larger project, being: “An exploration of enabling contexts (05K14).”
The main finding of the study is the low sense of community that the older persons in this particular residential care facility experience. This is supplemented by two themes that emerged throughout the study, being the lack of social interaction between the residents and the residents' need to have a sense of purpose. The occurrence of these two themes is supported by findings in community psychology and sense of community theories, and some of the findings of the study are consistent with findings reported in the literature. The study concludes with recommendations on how the residents' sense of community could be enhanced. / Thesis (M.A. (Research Psychology))--North-West University, Potchefstroom Campus, 2012.
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Persepsie van grondslagfase-onderwysers en ouers aangaande die effektiwiteit van vestibulere oefeninge om sensoriese en motoriese ontwikkeling te bevorderClaassens, Heidi 01 1900 (has links)
Abstracts in Afrikaans and English / Inklusiewe onderrig ondersteun die insluiting van alle leerders met verskillende behoeftes en vaardighede in klaskamers, wat baie keer te groot, of te verskillend vir doeltreffende onderrig is. Beweging as deel van ‘n vroeë leerervaring is noodsaaklik vir optimale neurale ontwikkeling. Dit beïnvloed organisasie en stimuleer die spesifieke neurologiese sisteme nodig vir optimale funksionering en ontwikkeling van die brein. Sensoriese integrasie disfunksie word gesien as die wortel van baie leerprobleme. Die vestibulêre sisteem is direk verbind met die sensoriese en motoriese sisteme. ‘n Sensoriese integrasie disfunksie het ‘n duidelike invloed op die vestibulêre sisteem. Die vestibulêre sisteem het baie interkonneksies met baie dele in die brein, byvoorbeeld propriosepsie en die tassisteem. Doeltreffende funksionering van die sensoriese, motoriese en vestibulêre sisteme word verlang vir ‘n hoë vlak van prestasieverrigting in sport en akademie. Wanneer die vestibulêre sisteem gestimuleer word, het dit ‘n direkte positiewe invloed op die sensoriese en motoriese ontwikkeling van leerders.
Die doel van hierdie studie was om te bepaal wat die persepsie van grondslagfase-onderwysers en ouers is oor die rol en voordele wat vestibulêre oefeninge te weeg kan bring in die motoriese en sensoriese ontwikkeling van leerders.
Leerders in graad 1 van ‘n privaatskool, asook van grade 2 en 3 van ‘n plaasskool is gekies as deelnemers in die studie. Die keuse van leerders was op grond van die bereidwilligheid van hulle en hul ouers om aan die studie deel te neem. Leerders het ‘n vestibulêre oefenprogram drie maal per week gedoen vir die tydperk van agt weke. Observasie-vraelyste is deur onderwysers en ouers ingevul na afloop van die derde sessie elke week. Vir die vraelys het ouers en onderwysers gekyk na die verbetering in aandagspan, konsentrasie, luistervaardigheid, oogkontak, sosiale interaksie en samewerking. Onderhoude is met ouers en onderwysers gedoen na aanleiding van die observasievraelyste wat vir die agt weke voltooi is. Transkripsies van die onderhoude is gedoen en afleidings is gemaak deur analise van die observasie-vraelyste en die getranskribeerde onderhoude.
Al ses die ontwikkelingsareas by beide skole het verbetering getoon oor die agt weke. Dit dui daarop dat vestibulêre oefeninge wel ‘n invloed op die sensoriese en motoriese ontwikkeling het. / Inclusive education promotes the inclusion of learners with different needs and capabilities in classes which are often too big and diverse for effective teaching. Movement as an early learning experience is necessary for optimal neural development. It influences organisation and stimulates the specific neurological systems required for optimal functioning and development of the brain. Sensory integrative dysfunction is believed to be at the root of many learning disorders. The vestibular system is directly connected with the sensory and motor systems. The vestibular system will be directly affected when a sensory integrations dysfunction presents. In fact, the vestibular system has many interconnections with almost every other part of the brain like proprioception and the tactile system. Proper functioning of the sensory, motor and vestibular systems is required for higher level performance in sport and academics. When the vestibular system is stimulated, it will result in a positive influence on the sensory and motor development of learners.
The aim of this study is to determine the perceptions of foundation phase teachers and parents regarding the role or benefits of vestibular exercises in promoting learners’ motor and sensory development.
Learners in Grade 1 of a private school and Grade 2 and 3 learners of a farm school in the northern Free State were selected as participants in the research. Learners were selected on the basis of the willingness of them and their parents to participate in the research. The participants did exercise sessions three times a week for thirty minutes over a period of eight weeks. Observation sheets were completed for all eight weeks, for the duration of the exercise program, by teachers and parents. These sheets were completed weekly after the third sessions in that week. The observation sheets listed concentration, attention span, listening, eye contact, cooperation, social interaction and self-esteem as developmental areas. Interviews were done after the period of eight weeks with the parents and teachers. The interviews conducted with both parties were taped and meticulously transcribed. This helped the researcher to get a better understanding of the study and to analise data and draw conclusions.All six areas of development showed improvement at both schools over the period of eight weeks. This indicates that stimulating the vestibular system promotes sensory and motor development. / Inclusive Education / M. Ed. (Inklusiewe Onderwys)
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