Biodiversity crisis and recovery during the Triassic-Jurassic greenhouse interval: testing ocean acidification hypotheses

The Late Rhaetian (Late Triassic) extinction event is characterised by shelled species showing a reduction in size, and thickness, which together with changed mineralogy is thought to be as a result of increased atmospheric pCO2 levels. Similar morphological changes have been demonstrated for extant species exposed experimentally to high CO2 leading to the hypothesis that Late Triassic extinctions were linked with global ocean acidification and increased oceanic palaeotemperatures. Consequently, the aim of this present work was to test this ocean acidification hypothesis by investigating morphological changes in selected shelled fossil species across this extinction event, and attempt to correlate them with changes in environmental temperature and pCO2. The abundance, size, shell thickness and mineralogy was determined for three common species, the bivalves Liostrea hisingeri and Plagiostoma gigantea and the ostracod Ogmoconchella aspinata collected from Triassic and Jurassic rocks from two locations in southwest England. Palaeotemperature was reconstructed from examination of these fossils and from the literature and atmospheric pCO2 estimated from published accounts. The shell size of bivalves increased during periods of high pCO2 and high palaeotemperature at both locations. Ostracod carapace sizes increased at St Audrie’s Bay but decreased at Lyme Regis during periods of high pCO2, while ostracod carapace size decreased during periods of high palaeotemperature at St Audrie’s Bay. However, ostracod shell thickness increased and decreased as pCO2 increased but shows no relationship with palaeotemperature at either location. Laboratory experiments on the effect of elevated pCO2 and elevated temperature on three modern species of ostracod was carried out. Modern species Leptocythere sp. and L. castanea subjected to either elevated pCO2 or elevated temperature showed increased dissolution, however size and thickness did not significantly change. In the same experimental conditions L. lacertosa showed increased dissolution however size continued to increase, while thickness was maintained. Comparison of fossil bivalve and ostracod data to modern high pCO2 and high temperature experiments illustrates some correlations to the modern experiments results indicating high pCO2 and high palaeotemperature conditions could have been occurring during the Triassic-Jurassic boundary interval. From the evidence presented, combined with an appropriate trigger (CAMP volcanism), it can be concluded that both ocean acidification and palaeotemperature were contributing to the species adaptations identified across the Triassic-Jurassic boundary interval

Expression of C4.4A in an in Vitro Human Tissue-Engineered Skin Model

A multi-LU-domain-containing protein denoted C4.4A exhibits a tightly regulated membrane-associated expression in the suprabasal layers of stratified squamous epithelia such as skin and the esophagus, and the expression of C4.4A is dysregulated in various pathological conditions. However, the biological function of C4.4A remains unknown. To enable further studies, we evaluated the expression of C4.4A in monolayer cultures of normal human keratinocytes and in tissue-engineered skin substitutes (TESs) produced by the self-assembly approach, which allow the formation of a fully differentiated epidermis tissue. Results showed that, in monolayer, C4.4A was highly expressed in the centre of keratinocyte colonies at cell-cell contacts areas, while some cells located at the periphery presented little C4.4A expression. In TES, emergence of C4.4A expression coincided with the formation of the stratum spinosum. After the creation of a wound within the TES, C4.4A expression was observed in the suprabasal keratinocytes of the migrating epithelium, with the exception of the foremost leading keratinocytes, which were negative for C4.4A. Our results are consistent with previous data in mouse embryogenesis and wound healing. Based on these findings, we conclude that this human TES model provides an excellent surrogate for studies of C4.4A and Haldisin expressions in human stratified epithelia

Songbird dynamics under the sea : acoustic interactions between humpback whales suggest song mediates male interactions

© The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Royal Society Open Science 5 (2018): 171298, doi:10.1098/rsos.171298.The function of song has been well studied in numerous taxa and plays a role in mediating both intersexual and intrasexual interactions. Humpback whales are among few mammals who sing, but the role of sexual selection on song in this species is poorly understood. While one predominant hypothesis is that song mediates male–male interactions, the mechanism by which this may occur has never been explored. We applied metrics typically used to assess songbird interactions to examine song sequences and movement patterns of humpback whale singers. We found that males altered their song presentation in the presence of other singers; focal males increased the rate at which they switched between phrase types (p = 0.005), and tended to increase the overall evenness of their song presentation (p = 0.06) after a second male began singing. Two-singer dyads overlapped their song sequences significantly more than expected by chance. Spatial analyses revealed that change in distance between singers was related to whether both males kept singing (p = 0.012), with close approaches leading to song cessation. Overall, acoustic interactions resemble known mechanisms of mediating intrasexual interactions in songbirds. Future work should focus on more precisely resolving how changes in song presentation may be used in competition between singing males.D.M.C. was supported by an EPA Science to Achieve Results (STAR) Fellowship for PhD research

Project Lotus: A really cool community-based initiative assisting women post-homelessness

In Canada, recent conservative estimates report upwards of 235,000 individuals are homeless on a given night. Of those experiencing precarious housing situations, women make up approximately 30% and are among the most vulnerable. Their residential insecurity has been further exacerbated with the community and social restrictions of the COVID-19 pandemic. Existing resources that assist women experiencing homelessness or housing insecurity are often stretched to the limit dealing with emergency and crisis housing situations, with less focus on post-shelter supports. To address this issue, a community-based participatory research initiative ‘Project Lotus - Hope Together’ was established in Montreal. Grounded in the World Health Organization’s Commission on Social Determinants of Health Framework, the overarching goal of this research is to co-design a housing supports program for women leaving a shelter stay. We created a cross-sectorial Advisory Committee consisting of women with lived experiences of homelessness, service providers, community leaders, and researchers. To date, we have conducted preliminary research (literature review, interviews with women with lived experience of homelessness, stakeholder meetings) to identity what has assisted women through this transition, and what barriers exist. We have also held virtual community consultation meetings to discuss preliminary findings of recommendations of key components that should be in a post-shelter support program for women. This presentation outlines the current findings and highlights the importance of participatory research. Implementing whole person care in the area of women’s homelessness requires both a comprehensive and individualized approach to help women and children secure home, health, and a sustainable future

MTHFD1 controls DNA methylation in Arabidopsis.

DNA methylation is an epigenetic mechanism that has important functions in transcriptional silencing and is associated with repressive histone methylation (H3K9me). To further investigate silencing mechanisms, we screened a mutagenized Arabidopsis thaliana population for expression of SDCpro-GFP, redundantly controlled by DNA methyltransferases DRM2 and CMT3. Here, we identify the hypomorphic mutant mthfd1-1, carrying a mutation (R175Q) in the cytoplasmic bifunctional methylenetetrahydrofolate dehydrogenase/methenyltetrahydrofolate cyclohydrolase (MTHFD1). Decreased levels of oxidized tetrahydrofolates in mthfd1-1 and lethality of loss-of-function demonstrate the essential enzymatic role of MTHFD1 in Arabidopsis. Accumulation of homocysteine and S-adenosylhomocysteine, genome-wide DNA hypomethylation, loss of H3K9me and transposon derepression indicate that S-adenosylmethionine-dependent transmethylation is inhibited in mthfd1-1. Comparative analysis of DNA methylation revealed that the CMT3 and CMT2 pathways involving positive feedback with H3K9me are mostly affected. Our work highlights the sensitivity of epigenetic networks to one-carbon metabolism due to their common S-adenosylmethionine-dependent transmethylation and has implications for human MTHFD1-associated diseases

Morphogenetic variability, cultural characteristics, aggressiveness, and transmission of Bipolaris oryzae isolates in Rio Grande do sul: Variabilidade morfogenética, características culturais, agressividade e transmissão de Bipolaris oryzae isolados no Rio Grande do Sul

Brown spot disease, caused by Bipolaris oryzae, is one of the most important rice diseases. This pathogen causes reductions in rice crop yield and quality, and its variability has been a problem for the management of brown spot disease due to its morphological and cultural similarity with other species that cause leaf spots and grain blight. The aim of this study was to determine the variability of B. oryzae isolates using different approaches and report information on patterns in aggressiveness and transmission of this pathogen from rice seed to seedlings. Fifteen isolates from different geographic rice crop regions of Rio Grande do Sul were used. The isolates were analyzed for genetic diversity, morphological and cultural characteristics, aggressiveness, and transmission ability from rice seeds to seedlings. Isolates fell into five morphological groups, based on cultural characteristics. Range values of the spore dimensions, color and mycelial growth showed high variation among the isolates. The most aggressive and transmissible isolates were those that form black colonies and had suppressed growth. The results show that isolates from Rio Grande do Sul are morphologically and genetically diverse and distributed throughout the state. This is the first study in which isolates representing the main rice growing areas in Rio Grande do Sul were taken into consideration for the study of variability, aggressiveness, and transmission

Cognitive function prior to systemic therapy and subsequent well‐being in older breast cancer survivors: Longitudinal findings from the Thinking and Living with Cancer Study

ObjectiveTo investigate the relationships between self‐reported and objectively measured cognitive function prior to systemic therapy and subsequent well‐being outcomes over 24 months in older breast cancer survivors.MethodsData were from 397 women aged 60 to 98 diagnosed with non‐metastatic breast cancer in the Thinking and Living with Cancer Study recruited from 2010‐2016. Cognitive function was measured at baseline (following surgery, prior to systemic therapy) using neuropsychological assessments of attention, processing speed, and executive function (APE), learning and memory (LM), and the self‐reported FACT‐Cog scale. Well‐being was measured using the FACT‐G functional, physical, social, and emotional well‐being domain scales at baseline and 12 and 24 months later, scaled from 0 (low) to 100 (high). Linear mixed‐effects models assessed the relationships between each of baseline APE, LM, and FACT‐Cog quartiles with well‐being scores over 24 months, adjusted for confounding variables.ResultsAt baseline, older survivors in the lowest APE, LM, and FACT‐Cog score quartiles experienced poorer global well‐being than those in the highest quartiles. At 24 months, older survivors tended to improve in well‐being, and there were no differences according to baseline APE or LM scores. At 24 months, mean global well‐being was 80.3 (95% CI: 76.2‐84.3) among those in the lowest vs 86.6 (95% CI: 83.1‐90.1) in the highest FACT‐cog quartile, a clinically meaningful difference of 6.3 points (95% CI: 1.5‐11.1).ConclusionsAmong older breast cancer survivors, self‐reported, but not objective cognitive impairments, were associated with lower global well‐being over the first 2 years of survivorship.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155908/1/pon5376.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155908/2/pon5376_am.pd

Pre-treatment psychoneurological symptoms and their association with longitudinal cognitive function and quality of life in older breast cancer survivors

Context Symptoms affect quality of life (QOL), functional status, and cognitive function in cancer survivors, but older survivors are understudied. Objectives To identify prototypical pre-systemic therapy psychoneurological symptom clusters among older breast cancer survivors, and determine whether these symptom clusters predicted cognition and QOL over time. Methods Women with newly diagnosed non-metastatic breast cancer (n=319) and matched non-cancer controls (n=347) aged 60+ completed questionnaires and neuropsychological tests before systemic therapy and 12- and 24-months later. Latent class analysis identified clusters of survivors based upon their pre-therapy depression, anxiety, fatigue, sleep disturbance, and pain. Linear mixed-effects models examined changes in objective cognition, perceived cognition, and functional status (instrumental activities of daily living (IADL) disability, functional well-being, and breast cancer-specific QOL) by group, controlling for covariates. Results Nearly one-fifth of older survivors were classified as having a high pre-therapy symptoms (n=51; 16%); the remainder had a low symptoms (n=268; 84%); both groups improved over time on all outcomes. However, compared to the low symptom group and controls, survivors with high symptoms had lower baseline objective cognition and lower perceived cognition at baseline and 24-months, lower functional well-being at baseline and 12-months, greater IADL disability at baseline, and lower breast cancer-specific QOL at all time points (all p<0.05). Conclusion Nearly one-fifth of older breast cancer survivors had high psychoneurological symptoms at diagnosis, which, predict clinically meaningful decrements in perceived cognition and function in the first 24 months post-diagnosis. Pre-treatment psychoneurological symptom clusters could identify survivors for monitoring or intervention

Symptom burden among older breast cancer survivors: The Thinking and Living With Cancer (TLC) study

Background: Little is known about longitudinal symptom burden and its consequences for well-being, and if lifestyle moderates burden in older survivors. Methods: We report on 36-month data from survivors 60+ with newly diagnosed non-metastatic breast cancer and non-cancer controls recruited August 2010-June 2016. Symptom burden was a sum of self-reported symptoms/diseases: pain (yes/no), fatigue (FACT-fatigue), cognitive (FACT-cog), sleep problems (yes/no), depression (CES-D), anxiety (STAI), and cardiac problems and neuropathy (yes/no). Well-being was measured using the FACT-G, scaled from 0–100. Lifestyle included smoking, alcohol use, BMI, physical activity, and leisure activities. Mixed models assessed relationships between treatment group (chemotherapy +/− hormonal, hormonal only, control) and symptom burden, lifestyle, and covariates. Separate models tested the effects of fluctuations in symptom burden and lifestyle on function. Results: All groups reported high baseline symptoms, and levels remained high over time; survivor-control differences were most notable for cognitive and sleep problems, anxiety, and neuropathy. The adjusted burden score was highest among chemotherapy-exposed survivors, followed by hormonal therapy vs. controls (p<.001). Burden score was related to physical, emotional, and functional well-being (e.g., survivors with lower vs. higher burden scores had 12.4-point higher physical well-being score). The composite lifestyle score was not related to symptom burden or well-being, but physical activity was significantly associated with each outcome (<.005). Conclusions: Cancer and its treatments are associated with a higher level of actionable symptoms and greater loss of well-being over time in older breast cancer survivors than comparable non-cancer populations, suggesting the need for surveillance and opportunities for intervention