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1.
Cell ; 185(14): 2452-2468.e16, 2022 07 07.
Article in English | MEDLINE | ID: mdl-35768006

ABSTRACT

COVID survivors frequently experience lingering neurological symptoms that resemble cancer-therapy-related cognitive impairment, a syndrome for which white matter microglial reactivity and consequent neural dysregulation is central. Here, we explored the neurobiological effects of respiratory SARS-CoV-2 infection and found white-matter-selective microglial reactivity in mice and humans. Following mild respiratory COVID in mice, persistently impaired hippocampal neurogenesis, decreased oligodendrocytes, and myelin loss were evident together with elevated CSF cytokines/chemokines including CCL11. Systemic CCL11 administration specifically caused hippocampal microglial reactivity and impaired neurogenesis. Concordantly, humans with lasting cognitive symptoms post-COVID exhibit elevated CCL11 levels. Compared with SARS-CoV-2, mild respiratory influenza in mice caused similar patterns of white-matter-selective microglial reactivity, oligodendrocyte loss, impaired neurogenesis, and elevated CCL11 at early time points, but after influenza, only elevated CCL11 and hippocampal pathology persisted. These findings illustrate similar neuropathophysiology after cancer therapy and respiratory SARS-CoV-2 infection which may contribute to cognitive impairment following even mild COVID.


Subject(s)
COVID-19 , Influenza, Human , Neoplasms , Animals , Humans , Influenza, Human/pathology , Mice , Microglia/pathology , Myelin Sheath , Neoplasms/pathology , SARS-CoV-2
2.
Nature ; 623(7985): 139-148, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37748514

ABSTRACT

Post-acute infection syndromes may develop after acute viral disease1. Infection with SARS-CoV-2 can result in the development of a post-acute infection syndrome known as long COVID. Individuals with long COVID frequently report unremitting fatigue, post-exertional malaise, and a variety of cognitive and autonomic dysfunctions2-4. However, the biological processes that are associated with the development and persistence of these symptoms are unclear. Here 275 individuals with or without long COVID were enrolled in a cross-sectional study that included multidimensional immune phenotyping and unbiased machine learning methods to identify biological features associated with long COVID. Marked differences were noted in circulating myeloid and lymphocyte populations relative to the matched controls, as well as evidence of exaggerated humoral responses directed against SARS-CoV-2 among participants with long COVID. Furthermore, higher antibody responses directed against non-SARS-CoV-2 viral pathogens were observed among individuals with long COVID, particularly Epstein-Barr virus. Levels of soluble immune mediators and hormones varied among groups, with cortisol levels being lower among participants with long COVID. Integration of immune phenotyping data into unbiased machine learning models identified the key features that are most strongly associated with long COVID status. Collectively, these findings may help to guide future studies into the pathobiology of long COVID and help with developing relevant biomarkers.


Subject(s)
Antibodies, Viral , Herpesvirus 4, Human , Hydrocortisone , Lymphocytes , Myeloid Cells , Post-Acute COVID-19 Syndrome , SARS-CoV-2 , Humans , Antibodies, Viral/blood , Antibodies, Viral/immunology , Biomarkers/blood , Cross-Sectional Studies , Herpesvirus 4, Human/immunology , Hydrocortisone/blood , Immunophenotyping , Lymphocytes/immunology , Machine Learning , Myeloid Cells/immunology , Post-Acute COVID-19 Syndrome/diagnosis , Post-Acute COVID-19 Syndrome/immunology , Post-Acute COVID-19 Syndrome/physiopathology , Post-Acute COVID-19 Syndrome/virology , SARS-CoV-2/immunology
3.
J Environ Manage ; 354: 120243, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38422571

ABSTRACT

In the last two centuries, a high proportion of peatlands have been lost or severely degraded across the world. The value of peatlands is now well-recognised for biodiversity conservation, flood management, and carbon mitigation, with peatland restoration now central to many government policies for climate action. A challenge, however, is to determine 'natural' and 'disturbed' conditions of peatlands to establish realistic baselines for assessing degradation and setting restoration targets. This requires a tool or set of tools that can rapidly and reliably capture peatland condition across space and time. Our aim was to develop such a tool based on combined analysis of plant and testate amoebae; a group of shelled protists commonly used as indicators of ecological change in peatlands. The value of testate amoebae is well established in Northern Hemisphere Sphagnum-dominated peatlands; however, relatively little work has been undertaken for Southern Hemisphere peat forming systems. Here we provide the first assessment and comparison of the bioindicator value of testate amoebae and vascular plants in the context of Southern Hemisphere peatlands. Our results further demonstrate the unique ecohydrological dynamics at play in New Zealand peat forming systems that set them apart from Northern Hemisphere peatlands. Our results show that plant and testate amoeba communities provided valuable information on peatland condition at different scales, we found that testate amoebae tracked changes in the abiotic variables (depth to water table, pH, and conductivity) more closely than vascular plants. Our results further demonstrate that functional traits of testate amoebae showed promising relationships with disturbance. Amoeba test compression, aperture position and test size were linked to changes in hydrology driven by fluctuations in ground water tables; however, trait responses manifested differently in ombrotrophic and minerotrophic peatlands. Overall, testate amoebae provide a promising bioindicator for tracking degradation in New Zealand peatlands and a potential additional tool to assess peatland condition.


Subject(s)
Amoeba , Environmental Biomarkers , Amoeba/physiology , Wetlands , Biological Monitoring , New Zealand , Biodiversity , Soil , Plants , Ecosystem
4.
New Phytol ; 233(1): 496-504, 2022 01.
Article in English | MEDLINE | ID: mdl-34651304

ABSTRACT

Interactions between individual plant pathogens and their environment have been described many times. However, the relative contribution of different environmental parameters as controls of pathogen communities remains largely unknown. Here we investigate the importance of environmental factors, including geomorphology, climate, land use, soil and plant community composition, for a broad range of aboveground and belowground fungal, oomycete and bacterial plant pathogens. We found that plant community composition is the main driver of the composition and richness of plant pathogens after taking into account all other tested parameters, especially those related to climate and soil. In the face of future changes in climate and land use, our results suggest that changes in plant pathogen community composition and richness will primarily be mediated through changes in plant communities, rather than the direct effects of climate or soils.


Subject(s)
Plants , Soil , Bacteria , Biodiversity , Fungi , Soil Microbiology
5.
Pediatr Diabetes ; 23(7): 968-975, 2022 11.
Article in English | MEDLINE | ID: mdl-36054578

ABSTRACT

OBJECTIVES: We evaluated COVID-19 outcomes in children and young adults with type 1 diabetes (T1D) to determine if those with comorbidities are more likely to experience severe COVID-19 compared to those without. RESEARCH DESIGN AND METHODS: This cross-sectional study included questionnaire data on patients <25 years of age with established T1D and laboratory-confirmed COVID-19 from 52 sites across the US between April 2020 and October 2021. We examined patient factors and COVID-19 outcomes between those with and without comorbidities. Multivariate logistic regression analysis examined the odds of hospitalization among groups, adjusting for age, HbA1c, race and ethnicity, insurance type and duration of diabetes. RESULTS: Six hundred fifty-one individuals with T1D and COVID-19 were analyzed with mean age 15.8 (SD 4.1) years. At least one comorbidity was present in 31%, and more than one in 10%. Obesity and asthma were the most frequently reported comorbidities, present in 19% and 17%, respectively. Hospitalization occurred in 17% of patients and 52% of hospitalized patients required ICU level care. Patients with at least one comorbidity were almost twice as likely to be hospitalized with COVID-19 than patients with no comorbidities (Odds ratio 2.0, 95% CI: 1.3-3.1). This relationship persisted after adjusting for age, HbA1c, race and ethnicity (minority vs nonminority), insurance type (public vs. private), and duration of diabetes. CONCLUSIONS: Our findings show that comorbidities increase the risk for hospitalization with COVID-19 in children and young adults highlighting the need for tailored COVID-19 prevention and treatment strategies in T1D.


Subject(s)
COVID-19 , Diabetes Mellitus, Type 1 , Adolescent , COVID-19/epidemiology , Child , Comorbidity , Cross-Sectional Studies , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 1/epidemiology , Diabetes Mellitus, Type 1/therapy , Glycated Hemoglobin , Hospitalization , Humans , SARS-CoV-2 , Young Adult
6.
Pediatr Diabetes ; 23(5): 536-544, 2022 08.
Article in English | MEDLINE | ID: mdl-35872603

ABSTRACT

OBJECTIVE: The following report describes the evaluation of the ISPAD Science School for Physicians (ISSP) and for Healthcare Professionals (ISSHP) in terms of their efficiency and success. METHODS: All past attendees from 2000-2019 ISSP and 2004-2019 ISSHP programs were invited to respond to an online survey to assess perceived outcomes of the programs on career development, scientific enhancement, scientific networking, and social opportunities. RESULTS: One-third of the past ISSP (129/428), and approximately 43% of the past ISSHP attendees (105/245) responded to the surveys. Most of ISSP attendees reported that the programs supported their career (82%) by helping to achieve a research position (59%), being engaged with diabetes care (68%) or research (63%) or starting a research fellowship (59%). Responders indicated that ISSP was effective in increasing interest in diabetes research (87%) and enhancing the number (66%) and quality (83%) of scientific productions, and promotion of international collaborations (86%). After the ISSP, 34% of responders received research grants. From the first round of the ISSHP survey (2004-2013), responders reported have improved knowledge (60%), gained more confidence in research (69%), undertaken a research project (63%), and achieved a higher academic degree (27%). From the second round (2014-2019), participants indicated that the program was valuable/useful in workplace (94%) through understanding (89%) and conducting (68%) research and establishing communication from other participants (64%) or from faculty (42%). After the ISSHP, 17% had received awards. CONCLUSIONS: From the participants' viewpoint, both programs were effective in improving engagement with diabetes research, supporting career opportunities, increasing scientific skills, and enhancing networking and research activities.


Subject(s)
Diabetes Mellitus , Schools , Adolescent , Child , Diabetes Mellitus/therapy , Health Personnel , Humans
7.
Diabetes Spectr ; 35(1): 111-117, 2022 Feb 15.
Article in English | MEDLINE | ID: mdl-35308154

ABSTRACT

Background: Continuous glucose monitoring (CGM) can improve glycemic outcomes in pediatric type 1 diabetes management. However, its impact on the psychosocial functioning of caregivers is less well described. The objectives of this pilot study were to explore caregiver reasons for adding CGM to their child's type 1 diabetes management, parental psychosocial function before initiating CGM, and the relationship between the two. Methods: Thirty-two families with a child with type 1 diabetes from Rainbow Babies and Children's Hospital diabetes clinics who were initiating CGM were recruited over 3 months. Before CGM initiation, the caregivers completed the Fear of Hypoglycemia Scale, State-Trait Anxiety Inventory, Problem Areas in Diabetes Scale, and a questionnaire assessing their primary reason for starting CGM. Participant characteristics and questionnaire results were summarized with descriptive statistics. Participants were grouped by reason for starting CGM, and results were compared among groups using ANOVA and reporting the global F test. Results: Fifty percent of respondents indicated that they were starting CGM to optimize glycemic control. The majority of parents (71.8%) expressed worry about helplessness during a hypoglycemic episode. There were no statistically significant differences in patient characteristics or questionnaire results between groups. Forty-three percent of participating families started using CGM during the study's 8-month follow-up period. The main reason (64%) for not starting CGM was not having the chance to start the process of obtaining a CGM system. There were no statistically significant differences between children who did and did not start CGM. Conclusion: Caregivers have different reasons for starting CGM for their child with type 1 diabetes. Further studies are needed to understand whether these reasons are related to differences in psychosocial functioning. Despite interest in starting CGM, there remain barriers to implementation.

8.
Telemed J E Health ; 28(4): 495-500, 2022 04.
Article in English | MEDLINE | ID: mdl-34292768

ABSTRACT

Introduction: Telehealth was frequently used in the provision of care and remote patient monitoring (RPM) during the COVID-19 pandemic. The Precision Recovery Program (PRP) remotely monitored and supported patients with COVID-19 in their home environment. Materials and Methods: This was a single-center retrospective cohort study reviewing data acquired from the PRP clinical initiative. Results: Of the 679 patients enrolled in the PRP, 156 patients were screened by a clinician following a deterioration in symptoms and vital signs on a total of 240 occasions, and included in the analyses. Of these 240 occasions, 162 (67%) were escalated to the PRP physician. Thirty-six patients were referred to emergency department, with 12 (7%) admitted to the hospital. The most common risk factors coinciding with hospital admissions were cardiac (67%), age >65 (42%), obesity (25%), and pulmonary (17%). The most common symptoms reported that triggered a screening event were dyspnea/tachypnea (27%), chest pain (14%), and gastrointestinal issues (8%). Vital signs that commonly triggered a screening event were pulse oximetry (15%), heart rate (11%), and temperature (9%). Discussion: Common factors (risk factors, vital signs, and symptoms) among patients requiring screening, triage, and hospitalization were identified, providing clinicians with further information to support decision making when utilizing RPM in this cohort. Conclusion: A clinician-led RPM program for patients with acute COVID-19 infection provided supportive care and screening for deterioration. Similar models should be considered for implementation in COVID-19 cohorts and other conditions at risk of rapid clinical deterioration in the home setting.


Subject(s)
COVID-19 , COVID-19/epidemiology , Humans , Monitoring, Physiologic , Pandemics , Retrospective Studies , SARS-CoV-2 , Triage
9.
Pediatr Diabetes ; 22(5): 807-815, 2021 08.
Article in English | MEDLINE | ID: mdl-33887095

ABSTRACT

OBJECTIVE: To describe the relationships among financial stress factors (perceived stress, financial stress, and financial independence) and psychological factors (depressive symptoms, trait anxiety, and diabetes distress) on self-management outcomes (HbA1c and diabetes-related quality of life) in emerging adults with type 1 diabetes. RESEARCH DESIGN AND METHODS: A descriptive, correlational, cross-sectional study examined 413 emerging adults, ages 18-25, from the Type 1 Diabetes Exchange Clinic Registry. Data were collected via REDCap surveys using the Personal Financial Well-Being Scale, Willingness to Pay Scale, Financial Independence Visual Analog Scale, Center for Epidemiological Studies-Depression Inventory, State-Trait Anxiety Inventory, The Type 1 Diabetes Distress Scale, and Diabetes Quality of Life Measure. Hierarchical Multiple Regression analyses explored significant barriers to self-management outcomes. RESULTS: Hierarchical Multiple Regression analyses revealed that 20.6% of variance in HbA1c (F = 15.555, p < 0.001) was explained by greater financial stress (ß = -0.197, p < 0.001), willingness to pay (ß = -0.220, p < 0.001), disease duration (ß = 0.119, p = 0.014), and diabetes distress (ß = 0.181, p < 0.001); 64.5% of the variance in diabetes-related quality of life (F = 148.469, p < 0.001) was significantly explained by greater financial stress (ß = -0.112, p = 0.002), diabetes distress (ß = 0.512, p < 0.001), trait anxiety (ß = 0.183, p = 0.001) and depressive symptoms (ß = 0.162, p = 0.001). CONCLUSIONS: Greater financial stress and psychological factors have detrimental impacts on self-management outcomes during emerging adulthood. Diabetes providers need to identify and address these factors in routine care and advocate for policy changes to support improved self-management outcomes.


Subject(s)
Diabetes Mellitus, Type 1/epidemiology , Financial Stress/epidemiology , Adolescent , Adult , Anxiety/epidemiology , Cross-Sectional Studies , Depression/epidemiology , Diabetes Mellitus, Type 1/economics , Female , Humans , Male , Self-Management/economics , Self-Management/psychology , Self-Management/statistics & numerical data , Surveys and Questionnaires , United States/epidemiology , Young Adult
10.
Intern Med J ; 51(7): 1168-1172, 2021 07.
Article in English | MEDLINE | ID: mdl-34278700

ABSTRACT

Time to symptom limitation (Tlim ) achieved during constant work rate tests is considerably more responsive to change than measures commonly recorded during ramp-based tests, such as peak rate of oxygen uptake and maximal work rate (Wmax ). There is limited literature on the use of, and physiological and symptom responses to, constant work rate cycle ergometry tests in people with cystic fibrosis (CF). The results of this study provide evidence that the constant work rate cycle ergometry test, when conducted at 80% of the Wmax , elicits peak physiological and symptom responses and appears to be safe in adults with CF. For clinicians prescribing exercise at an intensity approaching or equivalent to 80% of the Wmax in a non-laboratory-based setting, consideration needs to be given to the level of supervision and patient monitoring required.


Subject(s)
Cystic Fibrosis , Adult , Cystic Fibrosis/diagnosis , Ergometry , Exercise , Exercise Test , Humans
11.
Proc Natl Acad Sci U S A ; 115(7): 1546-1551, 2018 02 13.
Article in English | MEDLINE | ID: mdl-29440415

ABSTRACT

Over the past 50,000 y, biotic extinctions and declines have left a legacy of vacant niches and broken ecological interactions across global terrestrial ecosystems. Reconstructing the natural, unmodified ecosystems that preceded these events relies on high-resolution analyses of paleoecological deposits. Coprolites are a source of uniquely detailed information about trophic interactions and the behaviors, gut parasite communities, and microbiotas of prehistoric animal species. Such insights are critical for understanding the legacy effects of extinctions on ecosystems, and can help guide contemporary conservation and ecosystem restoration efforts. Here we use high-throughput sequencing (HTS) of ancient eukaryotic DNA from coprolites to reconstruct aspects of the biology and ecology of four species of extinct moa and the critically endangered kakapo parrot from New Zealand (NZ). Importantly, we provide evidence that moa and prehistoric kakapo consumed ectomycorrhizal fungi, suggesting these birds played a role in dispersing fungi that are key to NZ's natural forest ecosystems. We also provide the first DNA-based evidence that moa frequently supplemented their broad diets with ferns and mosses. Finally, we also find parasite taxa that provide insight into moa behavior, and present data supporting the hypothesis of coextinction between moa and several parasite species. Our study demonstrates that HTS sequencing of coprolites provides a powerful tool for resolving key aspects of ancient ecosystems and may rapidly provide information not obtainable by conventional paleoecological techniques, such as fossil analyses.


Subject(s)
Behavior, Animal/physiology , Birds/physiology , DNA/analysis , Ecology , Extinction, Biological , Fossils , Palaeognathae/physiology , Animals , DNA/genetics , Fungi/genetics , Parasites/genetics , Plants/genetics
12.
Mol Biol Evol ; 36(4): 784-797, 2019 04 01.
Article in English | MEDLINE | ID: mdl-30722030

ABSTRACT

The emergence of islands has been linked to spectacular radiations of diverse organisms. Although penguins spend much of their lives at sea, they rely on land for nesting, and a high proportion of extant species are endemic to geologically young islands. Islands may thus have been crucial to the evolutionary diversification of penguins. We test this hypothesis using a fossil-calibrated phylogeny of mitochondrial genomes (mitogenomes) from all extant and recently extinct penguin taxa. Our temporal analysis demonstrates that numerous recent island-endemic penguin taxa diverged following the formation of their islands during the Plio-Pleistocene, including the Galápagos (Galápagos Islands), northern rockhopper (Gough Island), erect-crested (Antipodes Islands), Snares crested (Snares) and royal (Macquarie Island) penguins. Our analysis also reveals two new recently extinct island-endemic penguin taxa from New Zealand's Chatham Islands: Eudyptes warhami sp. nov. and a dwarf subspecies of the yellow-eyed penguin, Megadyptes antipodes richdalei ssp. nov. Eudyptes warhami diverged from the Antipodes Islands erect-crested penguin between 1.1 and 2.5 Ma, shortly after the emergence of the Chatham Islands (∼3 Ma). This new finding of recently evolved taxa on this young archipelago provides further evidence that the radiation of penguins over the last 5 Ma has been linked to island emergence. Mitogenomic analyses of all penguin species, and the discovery of two new extinct penguin taxa, highlight the importance of island formation in the diversification of penguins, as well as the extent to which anthropogenic extinctions have affected island-endemic taxa across the Southern Hemisphere's isolated archipelagos.


Subject(s)
Genetic Speciation , Genome, Mitochondrial , Islands , Spheniscidae/genetics , Animals , Fossils , New Zealand , Phylogeography
13.
Intern Med J ; 50(9): 1091-1099, 2020 09.
Article in English | MEDLINE | ID: mdl-31389138

ABSTRACT

BACKGROUND: Within Australian and New Zealand cystic fibrosis (CF) centres, exercise testing and exercise training are common components of clinical care, but current practices regarding these components have not been reported. AIM: To determine the extent, scope and importance placed on exercise testing and exercise training within CF centres across Australia and New Zealand. METHODS: Information pertaining to exercise testing and training practices was sought by administering a survey to health professionals working in CF centres across Australia and New Zealand. The survey comprised five sections (46 questions) and was sent via an online link (Qualtrics). Response rate was optimised using the Dillman approach. Approval for this study was granted from the Human Research Ethics Committee at Curtin University (HRE2018-074). Completion of the survey was taken as informed consent. RESULTS: A response rate of 80% (n = 32/40) was achieved. Each state/territory in Australia, except the Northern Territory was represented in the survey responses. Eight of the 12 major regions in New Zealand were also represented. Regarding tests of exercise capacity, field-based tests were performed more commonly than laboratory-based tests (n = 28/32; 88% vs n = 11/32 centres; 34%; difference: 54%; 95% confidence interval 31-70%). Most (89%) respondents perceived field tests to be at least 'somewhat' important, whereas 91% of respondents perceived laboratory tests to be 'a little' to 'somewhat' important. Physical activity and/or exercise were discussed by at least one health professional in the CF team at every clinic appointment and/or annual review. Most centred offered outpatient exercise training each year to their patients (n = 24/32; 75%). CONCLUSION: This survey captures the current practices of exercise testing and training in CF centres across Australia and New Zealand.


Subject(s)
Cystic Fibrosis , Cystic Fibrosis/diagnosis , Cystic Fibrosis/therapy , Exercise , Exercise Test , Humans , New Zealand/epidemiology , Northern Territory , Surveys and Questionnaires
14.
Mol Ecol ; 28(16): 3786-3798, 2019 08.
Article in English | MEDLINE | ID: mdl-31314933

ABSTRACT

Little is known about the diversity patterns of plant pathogens and how they change with land use at a broad scale. We employed DNA metabarcoding to describe the diversity and composition of putative plant pathogen communities in three substrates (soil, roots, and leaves) across five major land uses at a national scale. Almost all plant pathogen communities (fungi, oomycetes, and bacteria) showed strong responses to land use and substrate type. Land use category could explain up to 24% of the variance in composition between communities. Alpha-diversity (richness) of plant pathogens was consistently lower in natural forests than in agricultural systems. In planted forests, there was also generally low pathogen alpha-diversity in soil and roots, but alpha-diversity in leaves was high compared with most other land uses. In contrast to alpha-diversity, differences in within-land use beta-diversity of plant pathogens (the predictability of plant pathogen communities within land use) were subtle. Our results show that large-scale patterns and distributions of putative plant pathogens can be determined using metabarcoding, allowing some of the first landscape level insights into these critically important communities.


Subject(s)
Bacteria/classification , Biodiversity , DNA Barcoding, Taxonomic , Fungi/classification , Oomycetes/classification , Plant Diseases/microbiology , Agriculture , Bacteria/pathogenicity , Forests , Fungi/pathogenicity , New Zealand , Oomycetes/pathogenicity , Plant Leaves/microbiology , Plant Roots/microbiology , Soil Microbiology
15.
Mol Phylogenet Evol ; 131: 72-79, 2019 02.
Article in English | MEDLINE | ID: mdl-30367976

ABSTRACT

Human impacts have substantially reduced avian biodiversity in many parts of the world, particularly on isolated islands of the Pacific Ocean. The New Zealand archipelago, including its five subantarctic island groups, holds breeding grounds for a third of the world's penguin species, including several representatives of the diverse crested penguin genus Eudyptes. While this species-rich genus has been little studied genetically, recent population estimates indicate that several Eudyptes taxa are experiencing demographic declines. Although crested penguins are currently limited to southern regions of the New Zealand archipelago, prehistoric fossil and archaeological deposits suggest a wider distribution during prehistoric times, with breeding ranges perhaps extending to the North Island. Here, we analyse ancient, historic and modern DNA sequences to explore two hypotheses regarding the recent history of Eudyptes in New Zealand, testing for (1) human-driven extinction of Eudyptes lineages; and (2) reduced genetic diversity in surviving lineages. From 83 prehistoric bone samples, each tentatively identified as 'Eudyptes spp.', we genetically identified six prehistoric penguin taxa from mainland New Zealand, including one previously undescribed genetic lineage. Moreover, our Bayesian coalescent analyses indicated that, while the range of Fiordland crested penguin (E. pachyrhynchus) may have contracted markedly over the last millennium, genetic DNA diversity within this lineage has remained relatively constant. This result contrasts with human-driven biodiversity reductions previously detected in several New Zealand coastal vertebrate taxa.


Subject(s)
DNA, Ancient/analysis , Genetic Variation , Phylogeny , Spheniscidae/genetics , Animals , Bayes Theorem , Biodiversity , Electron Transport Complex IV/genetics , Fossils , Haplotypes/genetics , Humans , New Zealand , Pacific Ocean , Population Dynamics , Spheniscidae/classification , Time Factors
16.
Glob Chang Biol ; 25(5): 1733-1745, 2019 05.
Article in English | MEDLINE | ID: mdl-30706600

ABSTRACT

Comprehending ecological dynamics requires not only knowledge of modern communities but also detailed reconstructions of ecosystem history. Ancient DNA (aDNA) metabarcoding allows biodiversity responses to major climatic change to be explored at different spatial and temporal scales. We extracted aDNA preserved in fossil rodent middens to reconstruct late Quaternary vegetation dynamics in the hyperarid Atacama Desert. By comparing our paleo-informed millennial record with contemporary observations of interannual variations in diversity, we show local plant communities behave differentially at different timescales. In the interannual (years to decades) time frame, only annual herbaceous expand and contract their distributional ranges (emerging from persistent seed banks) in response to precipitation, whereas perennials distribution appears to be extraordinarily resilient. In contrast, at longer timescales (thousands of years) many perennial species were displaced up to 1,000 m downslope during pluvial events. Given ongoing and future natural and anthropogenically induced climate change, our results not only provide baselines for vegetation in the Atacama Desert, but also help to inform how these and other high mountain plant communities may respond to fluctuations of climate in the future.


Subject(s)
Biodiversity , Climate Change , Desert Climate , Plants , Chile , DNA, Ancient/analysis , Ecosystem , Fossils , Plant Dispersal , Plants/classification , Plants/genetics , Population Dynamics
17.
J Lipid Res ; 59(5): 872-883, 2018 05.
Article in English | MEDLINE | ID: mdl-29576550

ABSTRACT

Circulating apolipoprotein-defined lipoprotein subclasses (ADLS) and apolipoproteins predict vascular events in the general and type 2 diabetes populations, but data in T1D are limited. We examined associations of ADLS, serum apolipoproteins, and conventional lipids with carotid intima-media thickness (IMT) measured contemporaneously and 6 years later in 417 T1D participants [men: n = 269, age 42 ± 6 y (mean ± SD); women: n = 148, age 39 ± 8 y] in the Epidemiology of Diabetes Interventions and Complications study, the follow-up of the Diabetes Control and Complications Trial (DCCT). Date were analyzed by multiple linear regression stratified by sex, and adjusted for time-averaged hemoglobin A1C, diabetes duration, hypertension, BMI, albuminuria, DCCT randomization, smoking, statin treatment, and ultrasound devices. In cross-sectional analyses, lipoprotein B (Lp-B), Lp-B:C, Lp-B:E+Lp-B:C:E, Apo-A-II, Apo-B, Apo-C-III-HP (heparin precipitate; i.e., Apo-C-III in Apo-B-containing lipoproteins), and Apo-E were positively associated with common and/or internal carotid IMT in men, but only Apo-C-III (total) was (positively) associated with internal carotid IMT in women. In prospective analyses, Lp-B, Apo-B, and Apo-C-III-HP were positively associated with common and/or internal carotid IMT in men, while Lp-A1:AII and Apo-A1 were inversely associated with internal carotid IMT in women. The only significant prospective association between conventional lipids and IMT was between triacylglycerols and internal carotid IMT in men. ADLS and apolipoprotein concentrations may provide sex-specific biomarkers and suggest mechanisms for IMT in people with T1D.


Subject(s)
Apolipoproteins/blood , Carotid Intima-Media Thickness , Diabetes Mellitus, Type 1/blood , Adult , Apolipoproteins/classification , Cross-Sectional Studies , Female , Humans , Male , Regression Analysis
18.
Proc Biol Sci ; 285(1877)2018 04 25.
Article in English | MEDLINE | ID: mdl-29669903

ABSTRACT

Often the mutualistic roles of extinct species are inferred based on plausible assumptions, but sometimes palaeoecological evidence can overturn such inferences. We present an example from New Zealand, where it has been widely assumed that some of the largest-seeded plants were dispersed by the giant extinct herbivorous moa (Dinornithiformes). The presence of large seeds in preserved moa gizzard contents supported this hypothesis, and five slow-germinating plant species (Elaeocarpus dentatus, E. hookerianus, Prumnopitys ferruginea, P. taxifolia, Vitex lucens) with thick seedcoats prompted speculation about whether these plants were adapted for moa dispersal. However, we demonstrate that all these assumptions are incorrect. While large seeds were present in 48% of moa gizzards analysed, analysis of 152 moa coprolites (subfossil faeces) revealed a very fine-grained consistency unparalleled in extant herbivores, with no intact seeds larger than 3.3 mm diameter. Secondly, prolonged experimental mechanical scarification of E. dentatus and P. ferruginea seeds did not reduce time to germination, providing no experimental support for the hypothesis that present-day slow germination results from the loss of scarification in moa guts. Paradoxically, although moa were New Zealand's largest native herbivores, the only seeds to survive moa gut passage intact were those of small-seeded herbs and shrubs.


Subject(s)
Extinction, Biological , Herbivory , Palaeognathae/physiology , Seed Dispersal , Trees/physiology , Animals , Elaeocarpaceae/physiology , Fossils , New Zealand , Seeds/physiology , Tracheophyta/physiology , Vitex/physiology
19.
Parasitology ; 145(5): 646-655, 2018 04.
Article in English | MEDLINE | ID: mdl-29557324

ABSTRACT

Ancient samples present a number of technical challenges for DNA barcoding, including damaged DNA with low endogenous copy number and short fragment lengths. Nevertheless, techniques are available to overcome these issues, and DNA barcoding has now been used to successfully recover parasite DNA from a wide variety of ancient substrates, including coprolites, cesspit sediment, mummified tissues, burial sediments and permafrost soils. The study of parasite DNA from ancient samples can provide a number of unique scientific insights, for example: (1) into the parasite communities and health of prehistoric human populations; (2) the ability to reconstruct the natural parasite faunas of rare or extinct host species, which has implications for conservation management and de-extinction; and (3) the ability to view in 'real-time' processes that may operate over century- or millenial-timescales, such as how parasites responded to past climate change events or how they co-evolved alongside their hosts. The application of DNA metabarcoding and high-throughput sequencing to ancient specimens has so far been limited, but in future promises great potential for gaining empirical data on poorly understood processes such as parasite co-extinction.


Subject(s)
DNA Barcoding, Taxonomic , DNA, Ancient/isolation & purification , High-Throughput Nucleotide Sequencing/methods , Parasites/genetics , Animals , DNA, Ancient/analysis , Humans , Parasitic Diseases/parasitology
20.
Ann Intern Med ; 167(2): 95-102, 2017 07 18.
Article in English | MEDLINE | ID: mdl-28605777

ABSTRACT

Background: Debate exists as to whether the higher hemoglobin A1c (HbA1c) levels observed in black persons than in white persons are due to worse glycemic control or racial differences in the glycation of hemoglobin. Objective: To determine whether a racial difference exists in the relationship of mean glucose and HbA1c. Design: Prospective, 12-week observational study. Setting: 10 diabetes centers in the United States. Participants: 104 black persons and 104 white persons aged 8 years or older who had had type 1 diabetes for at least 2 years and had an HbA1c level of 6.0% to 12.0%. Measurements: Mean glucose concentration, measured by using continuous glucose monitoring and compared by race with HbA1c, glycated albumin, and fructosamine values. Results: The mean HbA1c level was 9.1% in black persons and 8.3% in white persons. For a given HbA1c level, the mean glucose concentration was significantly lower in black persons than in white persons (P = 0.013), which was reflected in mean HbA1c values in black persons being 0.4 percentage points (95% CI, 0.2 to 0.6 percentage points) higher than those in white persons for a given mean glucose concentration. In contrast, no significant racial differences were found in the relationship of glycated albumin and fructosamine levels with the mean glucose concentration (P > 0.20 for both comparisons). Limitation: There were too few participants with HbA1c levels less than 6.5% to generalize the results to such individuals. Conclusion: On average, HbA1c levels overestimate the mean glucose concentration in black persons compared with white persons, possibly owing to racial differences in the glycation of hemoglobin. However, because race only partially explains the observed HbA1c differences between black persons and white persons, future research should focus on identifying and modifying barriers impeding improved glycemic control in black persons with diabetes. Primary Funding Source: Helmsley Charitable Trust.


Subject(s)
Black People , Blood Glucose/metabolism , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/ethnology , Glycated Hemoglobin/metabolism , White People , Adolescent , Adult , Blood Glucose Self-Monitoring , Child , Female , Fructosamine/blood , Glycation End Products, Advanced , Humans , Male , Middle Aged , Prospective Studies , Serum Albumin/metabolism , United States , Young Adult , Glycated Serum Albumin
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