title: The Relationship Among Social Support, Domains of Parental Self-Efficacy and Distress in Parents of Young Children

authors: Mabbett-Sowerby, Sarsha

subjects: postpartum distress

abstract: The present cross-sectional study investigated the relationships amongst social support, parental self-efficacy and postpartum distress. Parents of children under two (N = 327) were recruited via social media and poster advertisements. They were asked to complete three questionnaires regarding social support (Family Support Scale; FSS), parental self-efficacy (Karitane Parenting Confidence Scale; KPCS) and emotional distress (Depression, Anxiety and Stress Scale; DASS).The participants from this study who had high levels of self-efficacy were found to be more likely to have high levels of social support; however, this correlation was not as strong as anticipated. Furthermore, the participants from this study who had high levels of selfefficacy were less likely to be experiencing distress symptoms; the strength of this correlation was moderate and similar to prior findings. To further explore the relationships among these constructs, a post-hoc exploratory factor analysis of the Karitane Parenting Confidence Scale (KPCS) was conducted; yielding two factors: parenting role confidence (PRC) and baby care confidence (BCC). These two factors of the KPCS were found to be correlated with depression, anxiety and stress; parenting role confidence had a stronger relationship with these variables. Additionally, it was found that a combination of parenting role confidence and baby care confidence had substantial power to predict depression, anxiety and stress; social support added a small but significant additional predictive value. These findings suggest that postpartum distress might be mitigated by providing interventions that would improve levels  of social support and parenting self-efficacy.

text: The Relationship Among Social Support, Domains of Parental Self-Efficacy and Distress in Parents of Young Children The present cross-sectional study investigated the relationships amongst social support, parental self-efficacy and postpartum distress. Parents of children under two (N = 327) were recruited via social media and poster advertisements. They were asked to complete three questionnaires regarding social support (Family Support Scale; FSS), parental self-efficacy (Karitane Parenting Confidence Scale; KPCS) and emotional distress (Depression, Anxiety and Stress Scale; DASS).The participants from this study who had high levels of self-efficacy were found to be more likely to have high levels of social support; however, this correlation was not as strong as anticipated. Furthermore, the participants from this study who had high levels of selfefficacy were less likely to be experiencing distress symptoms; the strength of this correlation was moderate and similar to prior findings. To further explore the relationships among these constructs, a post-hoc exploratory factor analysis of the Karitane Parenting Confidence Scale (KPCS) was conducted; yielding two factors: parenting role confidence (PRC) and baby care confidence (BCC). These two factors of the KPCS were found to be correlated with depression, anxiety and stress; parenting role confidence had a stronger relationship with these variables. Additionally, it was found that a combination of parenting role confidence and baby care confidence had substantial power to predict depression, anxiety and stress; social support added a small but significant additional predictive value. These findings suggest that postpartum distress might be mitigated by providing interventions that would improve levels  of social support and parenting self-efficacy.

year: 2023

title: Role of growth factors in the regulation of skeletal muscle mass, fibre type and fibre size

authors: Martyn, Julie Anne Kerr

abstract: Growth factors play an important role in the regulation of the growth and development of many tissues including muscle. Muscle is derived from somitic cells that differentiate to form myoblasts. These myoblasts then fuse to form myofibres. As these myofibres mature they take on the morphological, biochemical and physiological properties of mature muscle fibres. It is the plasticity of muscle fibres with respect to these properties that gives skeletal muscle its remarkable ability to adapt to different conditions of loading and usage. The aim of this thesis was to determine the role of growth factors in regulating muscle fibre type and fibre size in two different models of altered muscle mass.

Bovine muscle development was examined in normal foetuses (NM) and in double-muscled Belgian Blue foetuses (DM) carrying a mutation in the gene for myostatin. Muscle fibre type and fibre size were characterised using semi-automated computer-assisted image analysis after myofibrillar ATPase histochemical staining. Plasma IGF levels were measured, IGF-1 mRNA was measured using in situ hybridisation and IGF receptor binding was analysed by receptor autoradiography. Myostatin mRNA was analysed using semi-quantitative RT-PCR.

Skeletal muscle hypertrophy and atrophy were induced m adult rabbits by immobilisation of the hind limb with muscles in a lengthened and shortened position respectively. Fibre type and fibre size changes were analysed as described above and myostatin mRNA expression levels were measured using Northern blot analysis and semi-quantitative RT-PCR.

Results showed there was a biphasic change in the percentage of type 1 muscle fibres in both NM and DM, with the percentage initially declining, then increasing again. The percentage of type 1 fibres was consistently lower in DM. Circulating levels of IGF-1 increased with gestational age and levels of IGF-1 and IGF-2 were not different between NM and DM. IGF-1 mRNA expression in skeletal muscle declined with age in a pattern that was unrelated to changes in fibre type. Levels of IGF-1 mRNA were lower in DM during late gestation and this decrease was temporally linked to a reduced area of type 1 fibres in DM at this stage of development. Myostatin mRNA declined with gestational age, and levels of the mutant mRNA were higher in DM.

In induced hypertrophy, myostatin mRNA expression was lower than in controls and in atrophy, myostatin mRNA was elevated at 2 days but not at 6 days. There were no changes in fibre type or fibre size over the treatment period. Myostatin protein was evenly localised to all muscle fibre types.

In conclusion, IGF-1 appears to be unrelated to changes in fibre type during bovine muscle development, but may play a role in the regulation of fibre size. The DM condition is associated with a change in fibre type, but the role of myostatin in mediating this change remains unknown. Changes in myostatin mRNA in response to induced hypertrophy and atrophy strongly suggest an important role for myostatin as a negative regulator of skeletal muscle mass in postnatal animals.

text: Role of growth factors in the regulation of skeletal muscle mass, fibre type and fibre size Growth factors play an important role in the regulation of the growth and development of many tissues including muscle. Muscle is derived from somitic cells that differentiate to form myoblasts. These myoblasts then fuse to form myofibres. As these myofibres mature they take on the morphological, biochemical and physiological properties of mature muscle fibres. It is the plasticity of muscle fibres with respect to these properties that gives skeletal muscle its remarkable ability to adapt to different conditions of loading and usage. The aim of this thesis was to determine the role of growth factors in regulating muscle fibre type and fibre size in two different models of altered muscle mass.

Bovine muscle development was examined in normal foetuses (NM) and in double-muscled Belgian Blue foetuses (DM) carrying a mutation in the gene for myostatin. Muscle fibre type and fibre size were characterised using semi-automated computer-assisted image analysis after myofibrillar ATPase histochemical staining. Plasma IGF levels were measured, IGF-1 mRNA was measured using in situ hybridisation and IGF receptor binding was analysed by receptor autoradiography. Myostatin mRNA was analysed using semi-quantitative RT-PCR.

Skeletal muscle hypertrophy and atrophy were induced m adult rabbits by immobilisation of the hind limb with muscles in a lengthened and shortened position respectively. Fibre type and fibre size changes were analysed as described above and myostatin mRNA expression levels were measured using Northern blot analysis and semi-quantitative RT-PCR.

Results showed there was a biphasic change in the percentage of type 1 muscle fibres in both NM and DM, with the percentage initially declining, then increasing again. The percentage of type 1 fibres was consistently lower in DM. Circulating levels of IGF-1 increased with gestational age and levels of IGF-1 and IGF-2 were not different between NM and DM. IGF-1 mRNA expression in skeletal muscle declined with age in a pattern that was unrelated to changes in fibre type. Levels of IGF-1 mRNA were lower in DM during late gestation and this decrease was temporally linked to a reduced area of type 1 fibres in DM at this stage of development. Myostatin mRNA declined with gestational age, and levels of the mutant mRNA were higher in DM.

In induced hypertrophy, myostatin mRNA expression was lower than in controls and in atrophy, myostatin mRNA was elevated at 2 days but not at 6 days. There were no changes in fibre type or fibre size over the treatment period. Myostatin protein was evenly localised to all muscle fibre types.

In conclusion, IGF-1 appears to be unrelated to changes in fibre type during bovine muscle development, but may play a role in the regulation of fibre size. The DM condition is associated with a change in fibre type, but the role of myostatin in mediating this change remains unknown. Changes in myostatin mRNA in response to induced hypertrophy and atrophy strongly suggest an important role for myostatin as a negative regulator of skeletal muscle mass in postnatal animals.

year: 1999

title: My journey with te reo Māori: From primary schooling in the mid 20th century to retirement from full-time academic service in the early years of the 21st Century

authors: Houia-Roberts, Ngaere

subjects: New Zealand

abstract: This is not an academic article in the traditional sense. It is a personal account of my experiences, as a first language speaker of te reo Māori, of New Zealand's educational system from the middle of the 20th century to the early years of the 21st century, from the early days of my primary schooling, through my service as a teacher, teacher trainer and academic researcher until my retirement from full-time academic service in 2005. A great deal has been written about the ways in which attitudes and approaches to te reo Māori have changed over that period of time but very little has been written about how it felt to be part of these changes. Our society is based on facts and feelings. If our mokopuna are to understand the fabric of our society, they need to have access to feelings as well as to facts. In this paper, weft and warp, facts and feelings, are woven together. This personal account is dedicated to our mokopuna, to all of our mokopuna, whatever their origin and whatever their colour. The future of our society depends upon their understanding.

text: My journey with te reo Māori: From primary schooling in the mid 20th century to retirement from full-time academic service in the early years of the 21st Century This is not an academic article in the traditional sense. It is a personal account of my experiences, as a first language speaker of te reo Māori, of New Zealand's educational system from the middle of the 20th century to the early years of the 21st century, from the early days of my primary schooling, through my service as a teacher, teacher trainer and academic researcher until my retirement from full-time academic service in 2005. A great deal has been written about the ways in which attitudes and approaches to te reo Māori have changed over that period of time but very little has been written about how it felt to be part of these changes. Our society is based on facts and feelings. If our mokopuna are to understand the fabric of our society, they need to have access to feelings as well as to facts. In this paper, weft and warp, facts and feelings, are woven together. This personal account is dedicated to our mokopuna, to all of our mokopuna, whatever their origin and whatever their colour. The future of our society depends upon their understanding.

year: 2006-02