Contrasting regulation of leaf gas exchange of semi-arid tree species under repeated drought.

Predicting how plants respond to drought requires an understanding of how physiological mechanisms and drought response strategies occur, as these strategies underlie rates of gas exchange and productivity. We assessed the response of 11 plant traits to repeated experimental droughts in four co-occurring species of central Australia. The main goals of this study were to: (i) compare the response to drought between species; (ii) evaluate whether plants acclimated to repeated drought; and (iii) examine the degree of recovery in leaf gas exchange after cessation of drought. Our four species of study were two tree species and two shrub species, which field studies have shown to occupy different ecohydrological niches. The two tree species (Eucalyptus camaldulensis Dehnh. and Corymbia opaca (D.J.Carr & S.G.M.Carr) K.D.Hill & L.A.S.Johnson) had large reductions in stomatal conductance (gs) values, declining by 90% in the second drought. By contrast, the shrub species (Acacia aptaneura Maslin & J.E.Reid and Hakea macrocarpa A.Cunn. ex R.Br.) had smaller reductions gs in the second drought of 52 and 65%, respectively. Only A. aptaneura showed a physiological acclimatation to drought due to small declines in gs versus ᴪpd (0.08 slope) during repeated droughts, meaning they maintained higher rates of gs compared with plants that only experienced one final drought (0.19 slope). All species in all treatments rapidly recovered leaf gas exchange and leaf mass per area following drought, displaying physiological plasticity to drought exposure. This research refines our understanding of plant physiological responses to recurrent water stress, which has implications for modelling of vegetation, carbon assimilation and water use in semi-arid environments under drought

TRY plant trait database - enhanced coverage and open access

Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

Speculations on the application of foliar 13C discrimination to reveal groundwater dependency of vegetation and provide estimates of root depth and rates of groundwater use

© Author(s) 2018. Groundwater-dependent vegetation is globally distributed, having important ecological, social, and economic value. Along with the groundwater resources upon which it depends, this vegetation is under increasing threat through excessive rates of groundwater extraction. In this study we examined one shallow-rooted and two deep-rooted tree species at multiple sites along a naturally occurring gradient in depth-to-groundwater. We measured (i) stable isotope ratios of leaves (δ 13C), xylem, and groundwater (δ 2H and δ 18O); and (ii) leaf-vein density. We established that foliar discrimination of 13C (Δ13C) is a reliable indicator of groundwater use by vegetation and can also be used to estimate rooting depth. Through comparison with a continental-scale assessment of foliar Δ13C, we also estimated the upper limits to annual rates of groundwater use. We conclude that maximum rooting depth for both deep-rooted species ranged between 9.4 and 11.2 m and that annual rates of groundwater use ranged from ca. 1400 to 1700 mm for Eucalyptus camaldulensis and from 600 to 900 mm for Corymbia opaca. Several predictions about hydraulic and leaf traits arising from the conclusion that these two species made extensive use of groundwater were supported by additional independent studies of these species in central Australia

The present and future of serum diagnostic tests for testicular germ cell tumours.

Testicular germ cell tumours (GCTs) are the most common malignancy occurring in young adult men and the incidence of these tumours is increasing. Current research priorities in this field include improving overall survival for patients classified as being 'poor-risk' and reducing late effects of treatment for patients classified as 'good-risk'. Testicular GCTs are broadly classified into seminomas and nonseminomatous GCTs (NSGCTs). The conventional serum protein tumour markers α-fetoprotein (AFP), human chorionic gonadotrophin (hCG) and lactate dehydrogenase (LDH) show some utility in the management of testicular malignant GCT. However, AFP and hCG display limited sensitivity and specificity, being indicative of yolk sac tumour (AFP) and choriocarcinoma or syncytiotrophoblast (hCG) subtypes. Furthermore, LDH is a very nonspecific biomarker. Consequently, seminomas and NSGCTs comprising a pure embryonal carcinoma subtype are generally negative for these conventional markers. As a result, novel universal biomarkers for testicular malignant GCTs are required. MicroRNAs are short, non-protein-coding RNAs that show much general promise as biomarkers. MicroRNAs from two 'clusters', miR-371-373 and miR-302-367, are overexpressed in all malignant GCTs, regardless of age (adult or paediatric), site (gonadal or extragonadal) and subtype (seminomas, yolk sac tumours or embryonal carcinomas). A panel of four circulating microRNAs from these two clusters (miR-371a-3p, miR-372-3p, miR-373-3p and miR-367-3p) is highly sensitive and specific for the diagnosis of malignant GCT, including seminoma and embryonal carcinoma. In the future, circulating microRNAs might be useful in diagnosis, disease monitoring and prognostication of malignant testicular GCTs, which might also reduce reliance on serial CT scanning. For translation into clinical practice, important practical considerations now need addressing.The authors would like to acknowledge grant funding from CwCUK/GOSHCC (M.J.M. N.C. grant W1058), SPARKS (M.J.M. N.C. grant 11CAM01), CRUK (N.C. grant A13080) MRC (M.J.M. grant MC_EX_G0800464) and National Health Service funding to the Royal Marsden/Institute of Cancer Research National Institute for Health Research Biomedical Research Centre for Cancer (R.A.H.). The authors also thank the Max Williamson Fund, the Josh Carrick Foundation and The Perse Preparatory School, Cambridge for support.This is the author accepted manuscript. The final version is available fromNature Publishing Group via https://doi.org/10.1038/nrurol.2016.17

A pipeline to quantify serum and cerebrospinal fluid microRNAs for diagnosis and detection of relapse in paediatric malignant germ-cell tumours

Background:The current biomarkers alpha-fetoprotein and human chorionic gonadotropin have limited sensitivity and specificity for diagnosing malignant germ-cell tumours (GCTs). MicroRNAs (miRNAs) from the miR-371-373 and miR-302/367 clusters are overexpressed in all malignant GCTs, and some of these miRNAs show elevated serum levels at diagnosis. Here, we developed a robust technical pipeline to quantify these miRNAs in the serum and cerebrospinal fluid (CSF). The pipeline was used in samples from a cohort of exclusively paediatric patients with gonadal and extragonadal malignant GCTs, compared with appropriate tumour and non-tumour control groups.Methods:We developed a method for miRNA quantification that enabled sample adequacy assessment and reliable data normalisation. We performed qRT-PCR profiling for miR-371-373 and miR-302/367 cluster miRNAs in a total of 45 serum and CSF samples, obtained from 25 paediatric patients.Results:The exogenous non-human spike-in cel-miR-39-3p and the endogenous housekeeper miR-30b-5p were optimal for obtaining robust serum and CSF qRT-PCR quantification. A four-serum miRNA panel (miR-371a-3p, miR-372-3p, miR-373-3p and miR-367-3p): (i) showed high sensitivity/specificity for diagnosing paediatric extracranial malignant GCT; (ii) allowed early detection of relapse of a testicular mixed malignant GCT; and (iii) distinguished intracranial malignant GCT from intracranial non-GCT tumours at diagnosis, using CSF and serum samples.Conclusions:The pipeline we have developed is robust, scalable and transferable. It potentially promises to improve clinical management of paediatric (and adult) malignant GCTs

Bioelectrical signals and ion channels in the modeling of multicellular patterns and cancer biophysics

Bioelectrical signals and ion channels are central to spatial patterns in cell ensembles, a problem of fundamental interest in positional information and cancer processes. We propose a model for electrically connected cells based on simple biological concepts: i) the membrane potential of a single cell characterizes its electrical state; ii) the long-range electrical coupling of the multicellular ensemble is realized by a network of gap junction channels between neighboring cells; and iii) the spatial distribution of an external biochemical agent can modify the conductances of the ion channels in a cell membrane and the multicellular electrical state. We focus on electrical effects in small multicellular ensembles, ignoring slow diffusional processes. The spatio-temporal patterns obtained for the local map of cell electric potentials illustrate the normalization of regions with abnormal cell electrical states. The effects of intercellular coupling and blocking of specific channels on the electrical patterns are described. These patterns can regulate the electrically-induced redistribution of charged nanoparticles over small regions of a model tissue. The inclusion of bioelectrical signals provides new insights for the modeling of cancer biophysics because collective multicellular states show electrical coupling mechanisms that are not readily deduced from biochemical descriptions at the individual cell level

The Pathology of EMT in Mouse Mammary Tumorigenesis

Epithelial-mesenchymal-transition (EMT) tumorigenesis in the mouse was first described over 100 years ago using various terms such as carcinosarcoma and without any comprehension of the underlying mechanisms. Such tumors have been considered artifacts of transplantation and of tissue culture. Recently, EMT tumors have been recognized in mammary glands of genetically engineered mice. This review provides a historical perspective leading to the current status in the context of some of the key molecular biology. The biology of mouse mammary EMT tumorigenesis is discussed with comparisons to human breast cancer

Hā Kūpuna National Resource Center for Native Hawaiian Elders: Decolonizing Research through Qualitative Methods and Community Partnership

Housed under the Thompson School of Social Work & Public Health at the University of Hawai‘i at Mānoa, Hā Kūpuna National Resource Center for Native Hawaiian Elders, strives to decolonize Western research as we increase opportunities of Native Hawaiian elders to pass their knowledge and stories to younger generations. One of Hā Kūpuna’s current projects is a five-year qualitative study examining healthcare experiences among Native Hawaiian elders in rural communities to gain advice for medical and social service providers to improve Native Hawaiian health. The project was co-designed by ALU LIKE, Inc.’s Kumu Kahi program (Elderly Services Department), which advised us to conduct a series of three interviews with each elder to build rapport before jumping into questions about healthcare. The first interview focuses on establishing rapport and learning about the kupuna’s family and everyday life. The second interview asks about values they learned from their own kupuna, what they want to pass to their mo`opuna, and other strengths and resiliencies. The third interview hones in on healthcare experiences they had over their lifetime and what advice they would like to share with providers. Results from the first 26 kūpuna have revealed that many kūpuna grew up with limited access to allopathic healthcare (healthcare providers treating diseases and symptoms with drugs and surgery) and that families treated many illnesses and injuries with traditional Hawaiian cultural healing practices, including lāʻau lapaʻau (plant-based medicine), lomilomi (massage), and ho`oponopono (conflict resolution). Even with the increased access and utilization of allopathic medicine, many kūpuna preferred cultural practices or a combination of both. Kūpuna advised that allopathic healthcare providers should take the time to gain knowledge of Native Hawaiian history and culture, allow for use of both Hawaiian and allopathic modes of healing, and interact with patients on both a personal as well as a professional level. They also noted that increasing access to specialty care on Neighbor Islands could improve Native Hawaiian health and life expectancy. Results and experiences from the ALU LIKE interview project helped to inform the creation of a 48-page qualitative interviewing protocol aimed to help researchers avoid extractive practices by increasing their knowledge of Hawaiian history, engaging communities in research, and creating safe and trusting research environments. Although experiences of colonization and discrimination are unique to each Indigenous and minority group, this protocol can apply to other populations as they are at a similar risk for extractive research experiences as well. As elements of the protocols were developed, they were discussed in-depth with researchers, non-profit stakeholders, community-based organization leaders (including ALU LIKE, Inc.), and past research participants. The qualitative protocol includes sections summarizing the history of colonization and instances of poorly-executed research in Hawaiʻi that caused harm. Also included are examples of Native Hawaiian researchers who are changing the face of research, a guide for researcher self-reflection and cultural humility, roles for community members in research, data ownership and management, the need to give more than take from participants, and a step-by-step guide on how to successfully join with community partners to conduct one-on-one interviews. Included are tips on developing research questions, and gathering and reporting data in ways accessible to the community. This qualitative protocol can be used as a guide to decolonizing research. Hā Kūpuna is supported by the US Administration on Community Living (#90OIRC0001) and the Barbara Cox Anthony Endowment