'We are largely left out': workplace and psychosocial experiences of Australian general practitioners during the initial months of the COVID-19 pandemic.

BACKGROUND: The COVID-19 pandemic continues to exert a significant toll on the Australian primary healthcare system. Although wellbeing challenges faced by hospital-based healthcare workers are widely discussed, less is known about the experiences of general practitioners (GPs) during the initial phases of the pandemic. This paper reports qualitative survey data from Australian GPs, examining their workplace and psychosocial experiences during the initial months of the pandemic. METHODS: An Australia-wide, cross-sectional, online survey of frontline healthcare workers was conducted in 2020. A qualitative approach using content analysis was utilised to examine responses to four free-text questions from GPs. RESULTS: A total of 299 GPs provided 888 free-text responses. The findings reveal that general practice was overlooked and undervalued within the pandemic response, resulting in negative impacts on GP wellbeing. Four themes were identified: (1) marginalisation of GPs; (2) uncertainty, undersupported and undervalued in the workplace; (3) isolation and disrupted personal lives; and (4) strategies to support GPs during times of crises. Key concerns included poor access to personal protective equipment, occupational burnout and poor wellbeing, insufficient workplace support, and conflicting or confusing medical guidelines. CONCLUSIONS: Primary healthcare constitutes an essential pillar of the Australian healthcare system. This study presents the many factors that impacted on GP wellbeing during the COVID-19 pandemic. Enabling GP voices to be heard and including GPs in decision-making in preparation for future crises will enhance the delivery of primary care, reducing the burden on hospital services, and help sustain a safe and effective health workforce long term.

Biomechanics and strain mapping in bone as related to immediately-loaded dental implants.

The effects of alveolar bone socket geometry and bone-implant contact on implant biomechanics, and resulting strain distributions in bone were investigated. Following extraction of lateral incisors on a cadaver mandible, implants were placed immediately and bone-implant contact area, stability implant biomechanics and bone strain were measured. In situ biomechanical testing coupled with micro X-ray microscopy (µ-XRM) illustrated less stiff bone-implant complexes (701-822 N/mm) compared with bone-periodontal ligament (PDL)-tooth complexes (791-913 N/mm). X-ray tomograms illustrated that the cause of reduced stiffness was due to limited bone-implant contact. Heterogeneous elemental composition of bone was identified by using energy dispersive X-ray spectroscopy (EDS). The novel aspect of this study was the application of a new experimental mechanics method, that is, digital volume correlation, which allowed mapping of strains in volumes of alveolar bone in contact with a loaded implant. The identified surface and subsurface strain concentrations were a manifestation of load transferred to bone through bone-implant contact based on bone-implant geometry, quality of bone, implant placement, and implant design. 3D strain mapping indicated that strain concentrations are not exclusive to the bone-implant contact regions, but also extend into bone not directly in contact with the implant. The implications of the observed strain concentrations are discussed in the context of mechanobiology. Although a plausible explanation of surgical complications for immediate implant treatment is provided, extrapolation of results is only warranted by future systematic studies on more cadaver specimens and/or in vivo models.

Stem cell factor and granulocyte colony-stimulating factor reduce ß-amyloid deposits in the brains of APP/PS1 transgenic mice.

INTRODUCTION: Alzheimer's disease (AD) is widely recognized as a serious public health problem and heavy financial burden. Currently, there is no treatment that can delay or stop the progressive brain damage in AD. Recently, we demonstrated that stem cell factor (SCF) in combination with granulocyte colony-stimulating factor (G-CSF) (SCF+G-CSF) has therapeutic effects on chronic stroke. The purpose of the present study is to determine whether SCF+G-CSF can reduce the burden of ß-amyloid deposits in a mouse model of AD. METHODS: APP/PS1 transgenic mice were used as the model of AD. To track bone marrow-derived cells in the brain, the bone marrow of the APP/PS1 mice was replaced with the bone marrow from mice expressing green fluorescent protein (GFP). Six weeks after bone marrow transplantation, mice were randomly divided into a saline control group and a SCF+G-CSF-treated group. SCF in combination with G-CSF was administered subcutaneously for 12 days. Circulating bone marrow stem cells (CD117+ cells) were quantified 1 day after the final injection. Nine months after treatment, at the age of 18 months, mice were sacrificed. Brain sections were processed for immunohistochemistry to identify ß-amyloid deposits and GFP expressing bone marrow-derived microglia in the brain. RESULTS: Systemic administration of SCF+G-CSF to APP/PS1 transgenic mice leads to long-term reduction of ß-amyloid deposition in the brain. In addition, we have also observed that the SCF+G-CSF treatment increases circulating bone marrow stem cells and augments bone marrow-derived microglial cells in the brains of APP/PS1 mice. Moreover, SCF+G-CSF treatment results in enhancement of the co-localization of bone marrow-derived microglia and ß-amyloid deposits in the brain. CONCLUSIONS: These data suggest that bone marrow-derived microglia play a role in SCF+G-CSF-induced long-term effects to reduce ß-amyloid deposits. This study provides insights into the contribution of the hematopoeitic growth factors, SCF and G-CSF, to limit ß-amyloid accumulation in AD and may offer a new therapeutic approach for AD.