Living Alone, Loneliness, and Psychological Well-Being of Older Persons in Singapore

Studies of the psychological well-being of elderly living alone have yielded inconsistent results. Few investigators have distinguished living alone from loneliness in the same study. Thus, the present study examined the independent and interactive effects of living alone and loneliness on depressive symptoms (GDS score) and quality of life (SF-12 MCS score) in a prospective 2-year follow-up cohort study of 2808 community-dwelling older adults (aged ≥55 years) in Singapore, controlling for baseline covariates. In cross-sectional analysis, loneliness was a more robust predictor of GDS score than living arrangements; living alone, when controlled for loneliness, was not associated with GDS score. GDS score associated with living alone was worse for those who felt lonely than for those who did not feel lonely. Similar patterns of association were found in longitudinal analyses and for SF-12 MCS score, although not all were significant. Thus, though living alone predicted lower psychological well-being, its predictive ability was reduced when loneliness was taken into account and loneliness, a stronger predictor, worsened the psychological effects of living alone

Herd demography, sexual segregation and the effects of forest management on Bornean banteng Bos javanicus lowi in Sabah, Malaystian Borneo

Between 1973 and 2010, 39.5% of Sabah’s (Malaysian Borneo) natural forest cover was lost to deforestation and conversion to agriculture, therefore the remaining population of endangered Bornean banteng Bos javanicus lowi is being driven towards extinction. The Bornean banteng’s herd demography, sexual segregation and the effects of forest management were investigated at 393 camera locations in 6 forest reserves using generalised estimating equations (GEE) fitted via a generalised linear model (GLM). A total of 43344 camera trap nights and 832 independent banteng events were captured at 93 locations. The identification of 183 bantengs included 22 herds (>1 individual) and 12 solitary bulls, with a herd size range of 2 to 21. Significantly larger herds were observed in forest with <8 yr of post-logging regeneration (PLR), whereas herds were smaller in forest with <3, 4 and 16 yr of PLR. Within these forests, herds were significantly larger along logging roads than in open sites and on forest trails. Herds were significantly larger in upland compared to lowland dipterocarp forest, but significantly smaller when closer to the forest border. Bachelor herds were observed as frequently as mixed-sex herds, and there was a significantly higher capture frequency of female herds in the dry season, supporting the theory of sexual segregation. Frequency of calf births was highest in March and September, and calf captures peaked in June and July. This study contributes to a better understanding of banteng ecology, and will assist in the production of effective management strategies aimed at providing suitable habitat for re-population and enabling banteng population persistence

PPAR gamma-coactivator-1 alpha gene transfer reduces neuronal loss and amyloid-beta generation by reducing beta-secretase in an Alzheimer's disease model

Current therapies for Alzheimer’s disease (AD) are symptomatic and do not target the underlying Aβ pathology and other important hallmarks including neuronal loss. PPARγ-coactivator-1α (PGC-1α) is a cofactor for transcription factors including the peroxisome proliferator-activated receptor-γ (PPARγ), and it is involved in the regulation of metabolic genes, oxidative phosphorylation, and mitochondrial biogenesis. We previously reported that PGC-1α also regulates the transcription of β-APP cleaving enzyme (BACE1), the main enzyme involved in Aβ generation, and its expression is decreased in AD patients. We aimed to explore the potential therapeutic effect of PGC-1α by generating a lentiviral vector to express human PGC-1α and target it by stereotaxic delivery to hippocampus and cortex of APP23 transgenic mice at the preclinical stage of the disease. Four months after injection, APP23 mice treated with hPGC-1α showed improved spatial and recognition memory concomitant with a significant reduction in Aβ deposition, associated with a decrease in BACE1 expression. hPGC-1α overexpression attenuated the levels of proinflammatory cytokines and microglial activation. This effect was accompanied by a marked preservation of pyramidal neurons in the CA3 area and increased expression of neurotrophic factors. The neuroprotective effects were secondary to a reduction in Aβ pathology and neuroinflammation, because wild-type mice receiving the same treatment were unaffected. These results suggest that the selective induction of PGC-1α gene in specific areas of the brain is effective in targeting AD-related neurodegeneration and holds potential as therapeutic intervention for this disease

PPARγ-coactivator-1α gene transfer reduces neuronal loss and amyloid-β generation by reducing β-secretase in an Alzheimer’s disease model

Current therapies for Alzheimer’s disease (AD) are symptomatic and do not target the underlying Aβ pathology and other important hallmarks including neuronal loss. PPARγ-coactivator-1α (PGC-1α) is a cofactor for transcription factors including the peroxisome proliferator-activated receptor-γ (PPARγ), and it is involved in the regulation of metabolic genes, oxidative phosphorylation, and mitochondrial biogenesis. We previously reported that PGC-1α also regulates the transcription of β-APP cleaving enzyme (BACE1), the main enzyme involved in Aβ generation, and its expression is decreased in AD patients. We aimed to explore the potential therapeutic effect of PGC-1α by generating a lentiviral vector to express human PGC-1α and target it by stereotaxic delivery to hippocampus and cortex of APP23 transgenic mice at the preclinical stage of the disease. Four months after injection, APP23 mice treated with hPGC-1α showed improved spatial and recognition memory concomitant with a significant reduction in Aβ deposition, associated with a decrease in BACE1 expression. hPGC-1α overexpression attenuated the levels of proinflammatory cytokines and microglial activation. This effect was accompanied by a marked preservation of pyramidal neurons in the CA3 area and increased expression of neurotrophic factors. The neuroprotective effects were secondary to a reduction in Aβ pathology and neuroinflammation, because wild-type mice receiving the same treatment were unaffected. These results suggest that the selective induction of PGC-1α gene in specific areas of the brain is effective in targeting AD-related neurodegeneration and holds potential as therapeutic intervention for this disease

Application of sub-micrometer vibrations to mitigate bacterial adhesion

As a prominent concern regarding implantable devices, eliminating the threat of opportunistic bacterial infection represents a significant benefit to both patient health and device function. Current treatment options focus on chemical approaches to negate bacterial adhesion, however, these methods are in some ways limited. The scope of this study was to assess the efficacy of a novel means of modulating bacterial adhesion through the application of vibrations using magnetoelastic materials. Magnetoelastic materials possess unique magnetostrictive property that can convert a magnetic field stimulus into a mechanical deformation. In vitro experiments demonstrated that vibrational loads generated by the magnetoelastic materials significantly reduced the number of adherent bacteria on samples exposed to Escherichia coli, Staphylococcus epidermidis and Staphylococcus aureus suspensions. These experiments demonstrate that vibrational loads from magnetoelastic materials can be used as a post-deployment activated means to deter bacterial adhesion and device infection

Characterization of the mechanism of prolonged adaptation to osmotic stress of Jeotgalibacillus malaysiensis via genome and transcriptome sequencing analyses

Jeotgalibacillus malaysiensis, a moderate halophilic bacterium isolated from a pelagic area, can endure higher concentrations of sodium chloride (NaCl) than other Jeotgalibacillus type strains. In this study, we therefore chose to sequence and assemble the entire J. malaysiensis genome. This is the first report to provide a detailed analysis of the genomic features of J. malaysiensis, and to perform genetic comparisons between this microorganism and other halophiles. J. malaysiensis encodes a native megaplasmid (pJeoMA), which is greater than 600 kilobases in size, that is absent from other sequenced species of Jeotgalibacillus. Subsequently, RNA-Seq-based transcriptome analysis was utilised to examine adaptations of J. malaysiensis to osmotic stress. Specifically, the eggNOG (evolutionary genealogy of genes: Non-supervised Orthologous Groups) and KEGG (Kyoto Encyclopaedia of Genes and Genomes) databases were used to elucidate the overall effects of osmotic stress on the organism. Generally, saline stress significantly affected carbohydrate, energy, and amino acid metabolism, as well as fatty acid biosynthesis. Our findings also indicate that J. malaysiensis adopted a combination of approaches, including the uptake or synthesis of osmoprotectants, for surviving salt stress. Among these, proline synthesis appeared to be the preferred method for withstanding prolonged osmotic stress in J. malaysiensis

Barriers and facilitators to weight management in overweight and obese women living in Australia with PCOS: a qualitative study

BACKGROUND:Lifestyle modification targeting weight management is the first-line treatment for women with Polycystic Ovary Syndrome (PCOS) regardless of presenting symptoms. Women with PCOS are more likely to gain more weight compared with women without PCOS, which may be related to barriers in engaging in lifestyle modification. The aim of this study is to explore the experience of women with PCOS in weight management and to determine the facilitators and barriers to lifestyle modifications in women with PCOS. METHODS:Ten women with PCOS participated in focus groups and semi-structured telephone interviews on lifestyle and weight management in PCOS. Discussions were audio-recorded and transcribed verbatim. Thematic analysis of the transcripts was conducted. Thematic analysis of the transcripts were conducted using the method of constant comparison. RESULTS:Women in the current study attempted a wide range of weight loss interventions, but had difficulties losing weight and preventing weight regain. Women felt that having PCOS affected their ability to lose weight and to keep it off. Facilitators to lifestyle modification for weight management were reported as structured approaches such as having balanced meals and support by health professionals, peers, friends or family. Barriers to lifestyle changes in women with PCOS included logistical barriers such as time and cost, motivational barriers including tiredness or feeling unrewarded, environmental barriers such as not having access to safe places to exercise, emotional barriers such as having depressive and defeating thoughts, and relational barriers such as having unsupportive partner or prioritising children's meal preferences. CONCLUSIONS:Women with PCOS face a number of personal, environmental and social facilitators and barriers to lifestyle modification for weight loss. While many of these are also experienced by women without PCOS, women with PCOS face additional barriers in having low sense of self-confidence and high prevalence of negative thoughts which may impair their ability to maintain efforts in lifestyle modification over the long term. Future research should further explore the impact of the emotional and mental burden of PCOS on the management of weight and other aspects of PCOS. Future lifestyle intervention should also address the psychosocial aspect of PCOS.Siew Lim, Caroline A. Smith, Michael F. Costello, Freya MacMillan, Lisa Moran and Carolyn E