Genetic mapping of the LOSS OF PARTHENOGENESIS locus in Pilosella piloselloides and the evolution of apomixis in the Lactuceae.

Pilosella piloselloides var. praealta (syn. P. praealta; Hieracium praealtum) is a versatile model used to study gametophytic apomixis. In this system apomixis is controlled by three loci: one that controls the avoidance of meiosis (LOA), one that controls the avoidance of fertilization (LOP) and a third that controls autonomous endosperm formation (AutE). Using a unique polyhaploid mapping approach the LOP locus was mapped to a 654 kb genomic interval syntenic to linkage group 8 of Lactuca sativa. Polyhaploids form through the gametophytic action of a dominant determinant at LOP, so the mapped region represents both a functional and a physical domain for LOP in P. piloselloides. Allele sequence divergence (ASD) analysis of the PARTHENOGENESIS (PAR) gene within the LOP locus revealed that dominant PAR alleles in Pilosella remain highly similar across the genus, whilst the recessive alleles are more divergent. A previous report noted that dominant PAR alleles in both Pilosella and Taraxacum are modified by the presence of a class II transposable element (TE) in the promoter of the gene. This observation was confirmed and further extended to the related genus Hieracium. Sufficient differences were noted in the structure and location of the TE elements to conclude that TE insertional events had occurred independently in the three genera. Measures of allele crossover amongst the polyhaploids revealed that P. piloselloides is an autopolyploid species with tetrasomic inheritance. It was also noted that the dominant determinant of LOP in P. piloselloides could transmit via a diploid gamete (pollen or egg) but not via a haploid gamete. Using this information, a model is presented of how gametophytic apomixis may have evolved in several members of the Lactuceae, a tribe of the Asteraceae.

Evaluation of IMproving Palliative care Education and Training Using Simulation in Dementia (IMPETUS-D) a staff simulation training intervention to improve palliative care of people with advanced dementia living in nursing homes: a cluster randomised controlled trial.

BACKGROUND: People with dementia have unique palliative and end-of-life needs. However, access to quality palliative and end-of-life care for people with dementia living in nursing homes is often suboptimal. There is a recognised need for nursing home staff training in dementia-specific palliative care to equip them with knowledge and skills to deliver high quality care. OBJECTIVE: The primary aim was to evaluate the effectiveness of a simulation training intervention (IMPETUS-D) aimed at nursing home staff on reducing unplanned transfers to hospital and/or deaths in hospital among residents living with dementia. DESIGN: Cluster randomised controlled trial of nursing homes with process evaluation conducted alongside. SUBJECTS & SETTING: One thousand three hundred four people with dementia living in 24 nursing homes (12 intervention/12 control) in three Australian cities, their families and direct care staff. METHODS: Randomisation was conducted at the level of the nursing home (cluster). The allocation sequence was generated by an independent statistician using a computer-generated allocation sequence. Staff from intervention nursing homes had access to the IMPETUS-D training intervention, and staff from control nursing homes had access to usual training opportunities. The predicted primary outcome measure was a 20% reduction in the proportion of people with dementia who had an unplanned transfer to hospital and/or death in hospital at 6-months follow-up in the intervention nursing homes compared to the control nursing homes. RESULTS: At 6-months follow-up, 128 (21.1%) people with dementia from the intervention group had an unplanned transfer or death in hospital compared to 132 (19.0%) residents from the control group; odds ratio 1.14 (95% CI, 0.82-1.59). There were suboptimal levels of staff participation in the training intervention and several barriers to participation identified. CONCLUSION: This study of a dementia-specific palliative care staff training intervention found no difference in the proportion of residents with dementia who had an unplanned hospital transfer. Implementation of the intervention was challenging and likely did not achieve adequate staff coverage to improve staff practice or resident outcomes. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRN12618002012257 . Registered 14 December 2018.

A PARTHENOGENESIS allele from apomictic dandelion can induce egg cell division without fertilization in lettuce.

Apomixis, the clonal formation of seeds, is a rare yet widely distributed trait in flowering plants. We have isolated the PARTHENOGENESIS (PAR) gene from apomictic dandelion that triggers embryo development in unfertilized egg cells. PAR encodes a K2-2 zinc finger, EAR-domain protein. Unlike the recessive sexual alleles, the dominant PAR allele is expressed in egg cells and has a miniature inverted-repeat transposable element (MITE) transposon insertion in the promoter. The MITE-containing promoter can invoke a homologous gene from sexual lettuce to complement dandelion LOSS OF PARTHENOGENESIS mutants. A similar MITE is also present in the promoter of the PAR gene in apomictic forms of hawkweed, suggesting a case of parallel evolution. Heterologous expression of dandelion PAR in lettuce egg cells induced haploid embryo-like structures in the absence of fertilization. Sexual PAR alleles are expressed in pollen, suggesting that the gene product releases a block on embryogenesis after fertilization in sexual species while in apomictic species PAR expression triggers embryogenesis in the absence of fertilization.

Elevated transcription of transposable elements is accompanied by het-siRNA-driven de novo DNA methylation in grapevine embryogenic callus.

BACKGROUND: Somatic variation is a valuable source of trait diversity in clonally propagated crops. In grapevine, which has been clonally propagated worldwide for centuries, important phenotypes such as white berry colour are the result of genetic changes caused by transposable elements. Additionally, epiallele formation may play a role in determining geo-specific ('terroir') differences in grapes and thus ultimately in wine. This genomic plasticity might be co-opted for crop improvement via somatic embryogenesis, but that depends on a species-specific understanding of the epigenetic regulation of transposable element (TE) expression and silencing in these cultures. For this reason, we used whole-genome bisulphite sequencing, mRNA sequencing and small RNA sequencing to study the epigenetic status and expression of TEs in embryogenic callus, in comparison with leaf tissue. RESULTS: We found that compared with leaf tissue, grapevine embryogenic callus cultures accumulate relatively high genome-wide CHH methylation, particularly across heterochromatic regions. This de novo methylation is associated with an abundance of transcripts from highly replicated TE families, as well as corresponding 24 nt heterochromatic siRNAs. Methylation in the TE-specific CHG context was relatively low over TEs located within genes, and the expression of TE loci within genes was highly correlated with the expression of those genes. CONCLUSIONS: This multi-'omics analysis of grapevine embryogenic callus in comparison with leaf tissues reveals a high level of genome-wide transcription of TEs accompanied by RNA-dependent DNA methylation of these sequences in trans. This provides insight into the genomic conditions underlying somaclonal variation and epiallele formation in plants regenerated from embryogenic cultures, which is an important consideration when using these tissues for plant propagation and genetic improvement.

Simulation training in non-cancer palliative care for healthcare workers: a systematic review of controlled studies.

Background: The need for healthcare workers (HCWs) to have skills and knowledge in non-cancer palliative care has been recognised. Simulation is increasingly being used for palliative care training, offering participants the opportunity to learn in a realistic environment and fully interactive way. Objective: The aim of this systematic review was to summarise and critically appraise controlled studies on simulation training in non-cancer palliative care for HCWs. Selection: Medline, CINAHL, PubMed and Cochrane Library databases were searched using palliative care and simulation terms. Randomised controlled trials (RCTs), non-randomised RCTs and controlled before-and-after (CBA) studies were included. Two reviewers independently screened titles and abstracts and undertook full article review using predefined selection criteria. Studies that met the inclusion criteria had data extracted and risk of bias assessed using the Cochrane Effective Practice and Organisation of Care risk of bias criteria. Findings: Five articles were included: three RCTs and two CBA studies. All studies assessed learners' palliative care communication skills, most studies evaluated learners' perception of change in skills and one study assessed impact on patient outcomes and learners' change in behaviour when applied in practice. There was variation in intervention content, intensity and duration, outcome measures and study design, making it difficult to compare and synthesise results. Conclusion: There is a paucity of evidence to support simulation training to improve non-cancer palliative care. This review highlights the need for more robust research, including multicentre studies that use standardised outcome measures to assess clinician skills, changes in clinical practice and patient-related outcomes.

A study protocol for the development of a multivariable model predicting 6- and 12-month mortality for people with dementia living in residential aged care facilities (RACFs) in Australia.

BACKGROUND: For residential aged care facility (RACF) residents with dementia, lack of prognostic guidance presents a significant challenge for end of life care planning. In an attempt to address this issue, models have been developed to assess mortality risk for people with advanced dementia, predominantly using long-term care minimum data set (MDS) information from the USA. A limitation of these models is that the information contained within the MDS used for model development was not collected for the purpose of identifying prognostic factors. The models developed using MDS data have had relatively modest ability to discriminate mortality risk and are difficult to apply outside the MDS setting. This study will aim to develop a model to estimate 6- and 12-month mortality risk for people with dementia from prognostic indicators recorded during usual clinical care provided in RACFs in Australia. METHODS: A secondary analysis will be conducted for a cohort of people with dementia from RACFs participating in a cluster-randomized trial of a palliative care education intervention (IMPETUS-D). Ten prognostic indicator variables were identified based on a literature review of clinical features associated with increased mortality for people with dementia living in RACFs. Variables will be extracted from RACF files at baseline and mortality measured at 6 and 12 months after baseline data collection. A multivariable logistic regression model will be developed for 6- and 12-month mortality outcome measures using backwards elimination with a fractional polynomial approach for continuous variables. Internal validation will be undertaken using bootstrapping methods. Discrimination of the model for 6- and 12-month mortality will be presented as receiver operating curves with c statistics. Calibration curves will be presented comparing observed and predicted event rates for each decile of risk as well as flexible calibration curves derived using loess-based functions. DISCUSSION: The model developed in this study aims to improve clinical assessment of mortality risk for people with dementia living in RACFs in Australia. Further external validation in different populations will be required before the model could be developed into a tool to assist with clinical decision-making in the future.

Thermal Injury Deaths of Community-dwelling Older People With Dementia.

Although people with dementia are prone to the risk of fire and burn injuries, the relationship between fatal thermal injuries and dementia has not been investigated. We examined coronial files in the state of Victoria, Australia between July 1, 2000 and December 31, 2014, for unintentional thermal injury causing deaths of community dwelling people, aged 65 years and older to identify those with dementia. Mortality for Victorian populations with and without dementia was calculated using direct age standardization. In total, 105 deaths were identified of which 18 (17%) had dementia. Mortality was more than 3-fold greater for people with dementia (3.0 vs. 0.8 per 100,000 person-years) and they more often lived with others when the injury occurred (56%, n=10 vs. 29% n=25, P=0.028). Our results suggest that older people with dementia are at greater risk of death through thermal injury. Further research should consider investigating a larger population through combining databases across multiple jurisdictions.

A screen-based simulation training program to improve palliative care of people with advanced dementia living in residential aged care facilities and reduce hospital transfers: study protocol for the IMproving Palliative care Education and Training Using Simulation in Dementia (IMPETUS-D) cluster randomised controlled trial.

BACKGROUND: Many people with advanced dementia live in residential aged care homes. Care home staff need the knowledge and skills to provide high-quality end-of-life (EOL) dementia care. However, several studies have found EOL dementia care to be suboptimal, and care staff have reported they would benefit from training in palliative care and dementia. Simulation offers an immersive learning environment and has been shown to improve learners' knowledge and skills. However, there is little research on simulation training for residential care staff. This article presents the development and evaluation protocol of IMproving Palliative care Education and Training Using Simulation in Dementia (IMPETUS-D) - a screen-based simulation training program on palliative dementia care, targeted at residential care staff. IMPETUS-D aims to improve the quality of palliative care provided to people living with dementia in residential care homes, including avoiding unnecessary transfers to hospital. METHODS: A cluster RCT will assess the effect of IMPETUS-D. Twenty-four care homes (clusters) in three Australian cities will be randomised to receive either the IMPETUS-D intervention or usual training opportunities (control). The primary outcome is to reduce transfers to hospital and deaths in hospital by 20% over 6-months in the intervention compared to the control group. Secondary outcomes include uptake of goals of care plans over 6 and 12 months, change in staff knowledge and attitudes towards palliative dementia care over 6 months, change in transfers to hospital and deaths in hospital over 12 months. For the primary analysis logistic regression models will be used with standard errors weighted by the cluster effects. A mixed methods process evaluation will be conducted alongside the cluster RCT to assess the mechanisms of impact, the implementation processes and contextual factors that may influence the delivery and effects of the intervention. DISCUSSION: In Australia, the need for high-quality advanced dementia care delivered in residential aged care is growing. This study will assess the effect of IMPETUS-D a new simulation-based training program on dementia palliative and EOL care. This large multisite trial will provide robust evidence about the impact of the intervention. If successful, it will be distributed to the broader residential care sector. TRIAL REGISTRATION: ANZCTR, ACTRN12618002012257 . Registered 14 December 2018.

Comparative transcriptome analysis of the wild-type model apomict Hieracium praealtum and its loss of parthenogenesis (lop) mutant.

BACKGROUND: Asexual seed formation (apomixis) has been observed in diverse plant families but is rare in crop plants. The generation of apomictic crops would revolutionize agriculture, as clonal seed production provides a low cost and efficient way to produce hybrid seed. Hieracium (Asteraceae) is a model system for studying the molecular components of gametophytic apomixis (asexual seed reproduction). RESULTS: In this study, a reference transcriptome was produced from apomictic Hieracium undergoing the key apomictic events of apomeiosis, parthenogenesis and autonomous endosperm development. In addition, transcriptome sequences from pre-pollination and post-pollination stages were generated from a loss of parthenogenesis (lop) mutant accession that exhibits loss of parthenogenesis and autonomous endosperm development. The transcriptome is composed of 147,632 contigs, 50% of which were annotated with orthologous genes and their probable function. The transcriptome was used to identify transcripts differentially expressed during apomictic and pollination dependent (lop) seed development. Gene Ontology enrichment analysis of differentially expressed transcripts showed that an important difference between apomictic and pollination dependent seed development was the expression of genes relating to epigenetic gene regulation. Genes that mark key developmental stages, i.e. aposporous embryo sac development and seed development, were also identified through their enhanced expression at those stages. CONCLUSION: The production of a comprehensive floral reference transcriptome for Hieracium provides a valuable resource for research into the molecular basis of apomixis and the identification of the genes underlying the LOP locus.

Seeds of doubt: Mendel's choice of Hieracium to study inheritance, a case of right plant, wrong trait.

KEY MESSAGE: In this review, we explore Gregor Mendel's hybridization experiments with Hieracium , update current knowledge on apomictic reproduction and describe approaches now being used to develop true-breeding hybrid crops. From our perspective, it is easy to conclude that Gregor Mendel's work on pea was insightful, but his peers clearly did not regard it as being either very convincing or of much importance. One apparent criticism was that his findings only applied to pea. We know from a letter he wrote to Carl von Nägeli, a leading botanist, that he believed he needed to "verify, with other plants, the results obtained with Pisum". For this purpose, Mendel adopted Hieracium subgenus Pilosella, a phenotypically diverse taxon under botanical study at the time. What Mendel could not have known, however, is that the majority of these plants are not sexual plants like pea, but instead are facultatively apomictic. In these forms, the majority of seed arises asexually, and such progeny are, therefore, clones of the maternal parent. Mendel obtained very few hybrids in his Hieracium crosses, yet we calculate that he probably emasculated in excess of 5000 Hieracium florets to even obtain the numbers he did. Despite that effort, he was perplexed by the results, and they ultimately led him to conclude that "the hybrids of Hieracium show a behaviour exactly opposite to those of Pisum". Apomixis is now a topic of intense research interest, and in an ironic twist of history, Hieracium subgenus Pilosella has been developed as a molecular model to study this trait. In this paper, we explore further Mendel's hybridization experiments with Hieracium, update current knowledge on apomictic reproduction and describe approaches now being used to develop true-breeding hybrid crops.

THE DANGERS OF DEMENTIA: GETTING THE BALANCE RIGHT.

Australia's population is ageing and it is likely that there will be a threefold increase in the number of people living with dementia in the next 30 years. Caring for these individuals will incur a significant burden on our community both fiscal and personal. How we provide this care will say much about our compassion for and commitment to caring for those who are no longer part of the productive workforce. Individuals with dementia are a heterogeneous group with a wide range of function and capacity. Nevertheless, their impairment often requires a high level of formal care in order to reduce the risk of harm to themselves and others in the community. The imposition of such care arrangements can be invasive of their autonomy and in some cases their liberty. These issues are addressed in respect of some of the major risks of harm in a setting of dementia.

Sexual reproduction is the default mode in apomictic Hieracium subgenus Pilosella, in which two dominant loci function to enable apomixis.

Asexual seed formation, or apomixis, in the Hieracium subgenus Pilosella is controlled by two dominant independent genetic loci, LOSS OF APOMEIOSIS (LOA) and LOSS OF PARTHENOGENESIS (LOP). We examined apomixis mutants that had lost function in one or both loci to establish their developmental roles during seed formation. In apomicts, sexual reproduction is initiated first. Somatic aposporous initial (AI) cells differentiate near meiotic cells, and the sexual pathway is terminated as AI cells undergo mitotic embryo sac formation. Seed initiation is fertilization-independent. Using a partially penetrant cytotoxic reporter to inhibit meioisis, we showed that developmental events leading to the completion of meiotic tetrad formation are required for AI cell formation. Sexual initiation may therefore stimulate activity of the LOA locus, which was found to be required for AI cell formation and subsequent suppression of the sexual pathway. AI cells undergo nuclear division to form embryo sacs, in which LOP functions gametophytically to stimulate fertilization-independent embryo and endosperm formation. Loss of function in either locus results in partial reversion to sexual reproduction, and loss of function in both loci results in total reversion to sexual reproduction. Therefore, in these apomicts, sexual reproduction is the default reproductive mode upon which apomixis is superimposed. These loci are unlikely to encode genes essential for sexual reproduction, but may function to recruit the sexual machinery at specific time points to enable apomixis.

Deletion mapping of genetic regions associated with apomixis in Hieracium.

Although apomixis has been quoted as a technology with the potential to deliver benefits similar in scale to those achieved with the Green Revolution, very little is currently known of the genetic mechanisms that control this trait in plants. To address this issue, we developed Hieracium, a genus of daisies native to Eurasia and North America, as a genetic model to study apomixis. In a molecular mapping study, we defined the number of genetic loci involved in apomixis, and we explored dominance and linkage relationships between these loci. To avoid difficulties often encountered with inheritance studies of apomicts, we based our mapping effort on the use of deletion mutagenesis, coupled with amplified fragment length polymorphism (AFLP) as a genomic fingerprinting tool. The results indicate that apomixis in Hieracium caespitosum is controlled at two principal loci, one of which regulates events associated with the avoidance of meiosis (apomeiosis) and the other, an unlinked locus that controls events associated with the avoidance of fertilization (parthenogenesis). AFLP bands identified as central to both loci were isolated, sequenced, and used to develop sequence-characterized amplified region (SCAR) markers. The validity of the AFLP markers was verified by using a segregating population generated by hybridization. The validity of the SCAR markers was verified by their pattern of presence/absence in specific mutants. The mutants, markers, and genetic data derived from this work are now being used to isolate genes controlling apomixis in this system.