RESUMO
Many avian species endemic to Aotearoa New Zealand were driven to extinction or reduced to relict populations following successive waves of human arrival, due to hunting, habitat destruction and the introduction of mammalian predators. Among the affected species were the large flightless South Island takahe (Porphyrio hochstetteri) and the moho (North Island takahe; P. mantelli), with the latter rendered extinct and the former reduced to a single relictual population. Little is known about the evolutionary history of these species prior to their decline and/or extinction. Here we sequenced mitochondrial genomes from takahe and moho subfossils (12 takahe and 4 moho) and retrieved comparable sequence data from takahe museum skins (n = 5) and contemporary individuals (n = 17) to examine the phylogeny and recent evolutionary history of these species. Our analyses suggest that prehistoric takahe populations lacked deep phylogeographic structure, in contrast to moho, which exhibited significant spatial genetic structure, albeit based on limited sample sizes (n = 4). Temporal genetic comparisons show that takahe have lost much of their mitochondrial genetic diversity, likely due to a sudden demographic decline soon after human arrival (~750 years ago). Time-calibrated phylogenetic analyses strongly support a sister species relationship between takahe and moho, suggesting these flightless taxa diverged around 1.5 million years ago, following a single colonisation of New Zealand by a flighted Porphyrio ancestor approximately 4 million years ago. This study highlights the utility of palaeogenetic approaches for informing the conservation and systematic understanding of endangered species whose ranges have been severely restricted by anthropogenic impacts.
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Genoma Mitocondrial , Animais , Evolução Biológica , Aves/genética , DNA Mitocondrial/genética , Mamíferos/genética , Nova Zelândia , FilogeniaRESUMO
BACKGROUND: Autotransfusion following vaginal delivery has not been as widely adopted and existing data on this topic are limited to small case series. METHODS: This is a single-center retrospective matched cohort study. Deliveries exposed to autotransfusion during obstetric hemorrhage were matched to unexposed controls with obstetric hemorrhage who did not receive autotransfusion. The primary outcome was allogeneic transfusion of packed red blood cells. Planned secondary analyses included change in hemoglobin following delivery, composite maternal safety outcomes, and unplanned postpartum health care utilization. RESULTS: Thirty-six deliveries exposed to autotransfusion were matched to 144 unexposed controls. There was no significant difference in allogenic transfusion of packed red blood cells in the patients exposed to autotransfusion red with unexposed controls (adjusted OR 1.1; 95% CI 0.5-2.4). Deliveries that received autotransfusion had a less severe pre- to post-delivery decline in hemoglobin compared with unexposed controls across all values of QBL (p = .003). There were no significant differences in maternal morbidity outcomes evaluated in exposed versus unexposed deliveries. CONCLUSION: Autotransfusion in cases of vaginal obstetric hemorrhage did not attenuate rates of allogenic packed red blood cell transfusion but did result in a less severe pre- to postdelivery decline in hemoglobin at discharge. Autotransfusion cases did not have any markers of increased maternal morbidity when compared with a control group. These findings support emerging evidence indicating that autotransfusion of blood lost during vaginal obstetric hemorrhage is a safe and potentially effective tool for use in the management of obstetric hemorrhage.
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Hemorragia Pós-Parto , Gravidez , Feminino , Humanos , Hemorragia Pós-Parto/terapia , Transfusão de Sangue Autóloga , Estudos Retrospectivos , Estudos de Coortes , Parto Obstétrico/efeitos adversos , Período Pós-Parto , HemoglobinasRESUMO
Understanding the landscape factors governing population connectivity in riverine ecosystems represents an ongoing challenge for freshwater biologists. We used DNA sequence analysis to test the hypothesis that major geomorphological features underpin freshwater-limited fish diversity in a tectonically dynamic region of New Zealand. Phylogeographic analysis of 101 Galaxias depressiceps cytochrome b sequences, incorporating 55 localities from southern New Zealand, revealed 26 haplotypes, with only one shared among rivers. We detect strong hierarchical genetic differentiation both among and within river systems. Genetic structuring is particularly pronounced across the Taieri River system (63 individuals from 35 sites, 18 haplotypes), with 92% of variation partitioned among locations. Distinctive within-river genetic clusters are invariably associated with major subcatchment units, typically isolated by substantial gorges. The anomalous distribution of a single lineage across a major drainage divide is consistent with local, tectonically driven headwater capture. We conclude that major landscape features such as gorges can strongly partition riverine fish diversity and constrain freshwater biodiversity.
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Ecossistema , Osmeriformes , Animais , Nova Zelândia , DNA Mitocondrial/genética , Filogenia , Osmeriformes/genética , Rios , Variação GenéticaRESUMO
The evolution of Batesian mimicry - whereby harmless species avoid predation through their resemblance to harmful species - has long intrigued biologists. In rare cases, Batesian mimicry is linked to intraspecific colour variation, in which only some individuals within a population resemble a noxious 'model'. Here, we assess intraspecific colour variation within a widespread New Zealand stonefly, wherein highly melanized individuals of Zelandoperla closely resemble a chemically defended aposematic stonefly, Austroperla cyrene. We assess convergence in the colour pattern of these two species, compare their relative palatability to predators, and use genome-wide association mapping to assess the genetic basis of this resemblance. Our analysis reveals that melanized Zelandoperla overlap significantly with Austroperla in colour space but are significantly more palatable to predators, implying that they are indeed Batesian mimics. Analysis of 194,773 genome-wide SNPs reveals an outlier locus (ebony) strongly differentiating melanic versus non-melanic Zelandoperla. Genotyping of 338 specimens from a single Zelandoperla population indicates that ebony explains nearly 70% of the observed variance in melanism. As ebony has a well-documented role in insect melanin biosynthesis, our findings indicate this locus has a conserved function across deeply divergent hexapod lineages. Distributional records suggest a link between the occurrence of melanic Zelandoperla and the forested ecosystems where the model Austroperla is abundant, suggesting the potential for adaptive shifts in this system underpinned by environmental change.
Assuntos
Mimetismo Biológico , Insetos , Humanos , Animais , Ecossistema , Estudo de Associação Genômica Ampla , Mimetismo Biológico/genética , Neópteros , Comportamento Predatório , Evolução BiológicaRESUMO
Many researchers have questioned the ability of biota to adapt to rapid anthropogenic environmental shifts. Here, we synthesize emerging genomic evidence for rapid insect evolution in response to human pressure. These new data reveal diverse genomic mechanisms (single locus, polygenic, structural shifts; introgression) underpinning rapid adaptive responses to a variety of anthropogenic selective pressures. While the effects of some human impacts (e.g. pollution; pesticides) have been previously documented, here we highlight startling new evidence for rapid evolutionary responses to additional anthropogenic processes such as deforestation. These recent findings indicate that diverse insect assemblages can indeed respond dynamically to major anthropogenic evolutionary challenges. Our synthesis also emphasizes the critical roles of genomic architecture, standing variation and gene flow in maintaining future adaptive potential. Broadly, it is clear that genomic approaches are essential for predicting, monitoring and responding to ongoing anthropogenic biodiversity shifts in a fast-changing world.
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Aclimatação , Adaptação Fisiológica , Humanos , Adaptação Fisiológica/genética , Genômica , Biodiversidade , Evolução BiológicaRESUMO
Importance: Red blood cell transfusion is a common medical intervention with benefits and harms. Objective: To provide recommendations for use of red blood cell transfusion in adults and children. Evidence Review: Standards for trustworthy guidelines were followed, including using Grading of Recommendations Assessment, Development and Evaluation methods, managing conflicts of interest, and making values and preferences explicit. Evidence from systematic reviews of randomized controlled trials was reviewed. Findings: For adults, 45 randomized controlled trials with 20â¯599 participants compared restrictive hemoglobin-based transfusion thresholds, typically 7 to 8 g/dL, with liberal transfusion thresholds of 9 to 10 g/dL. For pediatric patients, 7 randomized controlled trials with 2730 participants compared a variety of restrictive and liberal transfusion thresholds. For most patient populations, results provided moderate quality evidence that restrictive transfusion thresholds did not adversely affect patient-important outcomes. Recommendation 1: for hospitalized adult patients who are hemodynamically stable, the international panel recommends a restrictive transfusion strategy considering transfusion when the hemoglobin concentration is less than 7 g/dL (strong recommendation, moderate certainty evidence). In accordance with the restrictive strategy threshold used in most trials, clinicians may choose a threshold of 7.5 g/dL for patients undergoing cardiac surgery and 8 g/dL for those undergoing orthopedic surgery or those with preexisting cardiovascular disease. Recommendation 2: for hospitalized adult patients with hematologic and oncologic disorders, the panel suggests a restrictive transfusion strategy considering transfusion when the hemoglobin concentration is less than 7 g/dL (conditional recommendations, low certainty evidence). Recommendation 3: for critically ill children and those at risk of critical illness who are hemodynamically stable and without a hemoglobinopathy, cyanotic cardiac condition, or severe hypoxemia, the international panel recommends a restrictive transfusion strategy considering transfusion when the hemoglobin concentration is less than 7 g/dL (strong recommendation, moderate certainty evidence). Recommendation 4: for hemodynamically stable children with congenital heart disease, the international panel suggests a transfusion threshold that is based on the cardiac abnormality and stage of surgical repair: 7 g/dL (biventricular repair), 9 g/dL (single-ventricle palliation), or 7 to 9 g/dL (uncorrected congenital heart disease) (conditional recommendation, low certainty evidence). Conclusions and Relevance: It is good practice to consider overall clinical context and alternative therapies to transfusion when making transfusion decisions about an individual patient.
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Transfusão de Eritrócitos , Hemoglobinas , Adulto , Criança , Humanos , Doenças Cardiovasculares , Tomada de Decisões , Transfusão de Eritrócitos/normas , Cardiopatias Congênitas , Hemoglobinas/análise , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Large-scale disturbance events have the potential to drastically reshape biodiversity patterns. Notably, newly vacant habitat space cleared by disturbance can be colonized by multiple lineages, which can lead to the evolution of distinct spatial "sectors" of genetic diversity within a species. We test for disturbance-driven sectoring of genetic diversity in intertidal southern bull kelp, Durvillaea antarctica (Chamisso) Hariot, following the high-magnitude 1855 Wairarapa earthquake in New Zealand. Specifically, we use genotyping-by-sequencing (GBS) to analyse fine-scale population structure across the uplift zone and apply machine learning to assess the fit of alternative recolonizaton models. Our analysis reveals that specimens from the uplift zone carry distinctive genomic signatures potentially linked to post-earthquake recolonization processes. Specifically, our analysis identifies two parapatric spatial-genomic sectors of D. antarctica at Turakirae Head, which experienced the most dramatic uplift. Based on phylogeographical modelling, we infer that bull kelp in the Wellington region was probably a source for recolonization of the heavily uplifted Turakirae Head coastline, via two parallel, eastward recolonization events. By identifying multiple parapatric genotypic sectors within a recently recolonized coastal region, the current study provides support for the hypothesis that competing lineage expansions can generate striking spatial structuring of genetic diversity, even in highly dispersive taxa.
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Terremotos , Kelp , Ecossistema , Genômica , Kelp/genética , FilogeografiaRESUMO
Major ecological disturbance events can provide opportunities to assess multispecies responses to upheaval. In particular, catastrophic disturbances that regionally extirpate habitat-forming species can potentially influence the genetic diversity of large numbers of codistributed taxa. However, due to the rarity of such disturbance events over ecological timeframes, the genetic dynamics of multispecies recolonization processes have remained little understood. Here, we use single nucleotide polymorphism (SNP) data from multiple coastal species to track the dynamics of cocolonization events in response to ancient earthquake disturbance in southern New Zealand. Specifically, we use a comparative phylogeographic approach to understand the extent to which epifauna (with varying ecological associations with their macroalgal hosts) share comparable spatial and temporal recolonization patterns. Our study reveals concordant disturbance-related phylogeographic breaks in two intertidal macroalgal species along with two associated epibiotic species (a chiton and an isopod). By contrast, two codistributed species, one of which is an epibiotic amphipod and the other a subtidal macroalga, show few, if any, genetic effects of palaeoseismic coastal uplift. Phylogeographic model selection reveals similar post-uplift recolonization routes for the epibiotic chiton and isopod and their macroalgal hosts. Additionally, codemographic analyses support synchronous population expansions of these four phylogeographically similar taxa. Our findings indicate that coastal paleoseismic activity has driven concordant impacts on multiple codistributed species, with concerted recolonization events probably facilitated by macroalgal rafting. These results highlight that high-resolution comparative genomic data can help reconstruct concerted multispecies responses to recent ecological disturbance.
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Alga Marinha , Ecossistema , Nova Zelândia , Filogenia , FilogeografiaRESUMO
Recent genomic analyses have highlighted parallel divergence in response to ecological gradients, but the extent to which altitude can underpin such repeated speciation remains unclear. Wing reduction and flight loss have apparently evolved repeatedly in montane insect assemblages and have been suggested as important drivers of hexapod diversification. We test this hypothesis using genomic analyses of a widespread wing-polymorphic stonefly species complex in New Zealand. We identified over 50,000 polymorphic genetic markers generated across almost 200 Zelandoperla fenestrata stonefly specimens using a newly generated plecopteran reference genome, to reveal widespread parallel speciation between sympatric full-winged and wing-reduced ecotypes. Rather than the existence of a single, widespread, flightless taxon (Zelandoperla pennulata), evolutionary genomic data reveal that wing-reduced upland lineages have speciated repeatedly and independently from full-winged Z. fenestrata. This repeated evolution of reproductive isolation between local ecotype pairs that lack mitochondrial DNA differentiation suggests that ecological speciation has evolved recently. A cluster of outlier single-nucleotide polymorphisms detected in independently wing-reduced lineages, tightly linked in an approximately 85 kb genomic region that includes the developmental "supergene" doublesex, suggests that this "island of divergence" may play a key role in rapid ecological speciation. [Ecological speciation; genome assembly; genomic island of differentiation; genotyping-by-sequencing; incipient species; plecoptera; wing reduction.].
Assuntos
Ecótipo , Especiação Genética , Insetos , Animais , Genoma de Inseto , Genômica , Insetos/classificação , Insetos/genética , Nova Zelândia , FilogeniaRESUMO
OBJECTIVE: To report maternal outcomes in a cohort of women who received autotransfusion of vaginally shed blood and to describe the feasibility of blood collection and cell salvage processing at the time of vaginal hemorrhage. STUDY DESIGN AND METHODS: We conducted a retrospective case series of patients who received autotransfusion of vaginally shed blood at the time of obstetric hemorrhage from January 2014 to August 2020. Maternal data and cell salvage utilization characteristics were abstracted from the electronic medical record. RESULTS: Sixty-four cases were identified in which autotransfusion of vaginally shed blood occurred during an obstetric hemorrhage. Median quantitative blood loss was 2175 ml (interquartile range 1500-2250 ml) with 89% of cases having a blood loss greater than 1000 ml. Patients on average received approximately 1.3 units of autologous blood product (384 ml, interquartile range 244-520 ml) and no direct adverse events were observed during transfusion. We observed heterogeneity in autologous blood volume across all values of quantitative blood loss. The need for allogenic blood transfusion was common and occurred in 72% of all cases (N = 46). There were no documented cases of maternal sepsis or severe infectious morbidity. CONCLUSION: In 64 cases where autotransfusion of vaginally shed blood occurred, autotransfusion was well tolerated. Heterogeneity in autologous blood volume collection likely represents the lack of standardized protocols for blood collection in the delivery room. Autotransfusion of vaginally shed blood is a feasible and reasonable technique to employ during severe obstetric hemorrhage.
Assuntos
Transfusão de Sangue Autóloga , Transfusão de Sangue , Transfusão de Sangue Autóloga/métodos , Feminino , Hemorragia , Humanos , Gravidez , Estudos RetrospectivosRESUMO
BACKGROUND: Obstetric hemorrhage is a leading cause of preventable maternal mortality. To combat this, obstetric organizations worldwide recommend consideration of autotransfusion during severe peripartum bleeding to minimize allogenic transfusion. Current guidelines for autotransfusion in obstetrics are limited to patients undergoing cesarean birth. At present, women experiencing vaginal obstetric hemorrhage are excluded from many obstetric autotransfusion protocols. However, emerging data suggest that autotransfusion of vaginally shed blood is both safe and feasible in the obstetric patient population. METHODS AND MATERIALS: In this review, we will provide an overview of the current literature surrounding cell salvage of vaginally send blood and a detailed outline of our institution's blood collection protocol. RESULTS: Recent data suggests autotransfusion of vaginally shed blood is both safe and effective. DISCUSSION: Implementation of autotransfusion technology into the delivery room is a critical next step for the advancement of transfusion medicine in obstetrics. This review provides an overview of the data surrounding autotransfusion of vaginally shed blood during maternal hemorrhage and describes practical suggestions for how it can be effectively implemented into routine practice.
Assuntos
Obstetrícia , Hemorragia Pós-Parto , Transfusão de Sangue , Transfusão de Sangue Autóloga , Cesárea , Feminino , Humanos , Hemorragia Pós-Parto/epidemiologia , Hemorragia Pós-Parto/terapia , GravidezRESUMO
Placenta accreta spectrum (PAS) disorder is a potentially life-threatening condition that can occur during pregnancy. PAS puts pregnant individuals at a very high risk of major blood loss, hysterectomy, and intensive care unit admission. These patients should receive care in a center with multidisciplinary experience and expertise in managing PAS disorder. Obstetric anesthesiologists play vital roles in the peripartum care of pregnant patients with suspected PAS. As well as providing high-quality anesthesia care, obstetric anesthesiologists coordinate peridelivery care, drive transfusion-related decision making, and oversee postpartum analgesia. However, there are a number of key knowledge gaps related to the anesthesia care of these patients. For example, limited data are available describing optimal anesthesia staffing models for scheduled and unscheduled delivery. Evidence and consensus are lacking on the ideal surgical location for delivery; primary mode of anesthesia for cesarean delivery; preoperative blood ordering; use of pharmacological adjuncts for hemorrhage management, such as tranexamic acid and fibrinogen concentrate; neuraxial blocks and abdominal wall blocks for postoperative analgesia; and the preferred location for postpartum care. It is also unclear how anesthesia-related decision making and interventions impact physical and mental health outcomes. High-quality international multicenter studies are needed to fill these knowledge gaps and advance the anesthesia care of patients with PAS.
Assuntos
Anestesia , Placenta Acreta , Hemorragia Pós-Parto , Anestesia/efeitos adversos , Transfusão de Sangue , Cesárea , Feminino , Humanos , Histerectomia , Placenta Acreta/diagnóstico , Placenta Acreta/cirurgia , Gravidez , Estudos RetrospectivosRESUMO
Climate shifts are key drivers of ecosystem change. Despite the critical importance of Antarctica and the Southern Ocean for global climate, the extent of climate-driven ecological change in this region remains controversial. In particular, the biological effects of changing sea ice conditions are poorly understood. We hypothesize that rapid postglacial reductions in sea ice drove biological shifts across multiple widespread Southern Ocean species. We test for demographic shifts driven by climate events over recent millennia by analyzing population genomic datasets spanning 3 penguin genera (Eudyptes, Pygoscelis, and Aptenodytes). Demographic analyses for multiple species (macaroni/royal, eastern rockhopper, Adélie, gentoo, king, and emperor) currently inhabiting southern coastlines affected by heavy sea ice conditions during the Last Glacial Maximum (LGM) yielded genetic signatures of near-simultaneous population expansions associated with postglacial warming. Populations of the ice-adapted emperor penguin are inferred to have expanded slightly earlier than those of species requiring ice-free terrain. These concerted high-latitude expansion events contrast with relatively stable or declining demographic histories inferred for 4 penguin species (northern rockhopper, western rockhopper, Fiordland crested, and Snares crested) that apparently persisted throughout the LGM in ice-free habitats. Limited genetic structure detected in all ice-affected species across the vast Southern Ocean may reflect both rapid postglacial colonization of subantarctic and Antarctic shores, in addition to recent genetic exchange among populations. Together, these analyses highlight dramatic, ecosystem-wide responses to past Southern Ocean climate change and suggest potential for further shifts as warming continues.
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Background: Allogeneic blood transfusions in oncologic surgery are associated with increased recurrence and mortality. Adverse effects on outcome could be reduced or avoided by using intraoperative autologous blood cell salvage (IOCS). However, there are concerns regarding the safety of the autologous IOCS blood. Previous meta-analyses from 2012 and 2020 did not identify increased risk of cancer recurrence after using autologous IOCS blood. The objective of this review was to reassess a greater number of IOCS-treated patients to present an updated and more robust analysis of the current literature. Methods: This systematic review includes full-text articles listed in PubMed, Cochrane, Cochrane Reviews, and Web of Science. We analyzed publications that discussed cell salvage or autotransfusion combined with the following outcomes: cancer recurrence, mortality, survival, allogeneic transfusion rate and requirements, length of hospital stay (LOS). To rate the strength of evidence, a Grading of Recommendations Assessment, Development and Evaluation (GRADE) of the underlying evidence was applied. Results: In the updated meta-analysis, 7 further observational studies were added to the original 27 observational studies included in the former 2020 analysis. Studies compared either unfiltered (n = 2,311) or filtered (n = 850) IOCS (total n = 3,161) versus non-IOCS use (n = 5,342). Control patients were either treated with autologous predonated blood (n = 484), with allogeneic transfusion (n = 4,113), or did not receive a blood transfusion (n = 745). However, the current literature still contains only observational studies on these topics, and the strength of evidence remains low. The risk of cancer recurrence was reduced in recipients of autologous salvaged blood with or without LDF (odds ratio [OR] 0.76, 95% confidence interval [CI]: 0.64-0.90) compared to nontransfused patients or patients with allogeneic transfusion. There was no difference in mortality (OR 0.95, 95% CI: 0.71-1.27) and LOS (mean difference -0.07 days, 95% CI: -0.63 to 0.48) between patients treated with IOCS blood or those in whom IOCS was not used. Due to high heterogeneity, transfusion rates or volumes could not be analyzed. Conclusion: Randomized controlled trials comparing mortality and cancer recurrence rate of IOCS with or without LDF filtration versus allogeneic blood transfusion were not found. Outcome was similar or better in patients receiving IOCS during cancer surgery compared to patients with allogeneic blood transfusion or nontransfused patients.
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Biologists have long been intrigued by apparently predictable and repetitive evolutionary trajectories inferred across a variety of lineages and systems. In recent years, high-throughput sequencing analyses have started to transform our understanding of such repetitive shifts. While researchers have traditionally categorized such shifts as either "convergent" or "parallel," based on relatedness of the lineages involved, emerging genomic insights provide an opportunity to better describe the actual evolutionary mechanisms at play. A synthesis of recent genomic analyses confirms that convergence is the predominant driver of repetitive evolution among species, whereas repeated sorting of standing variation is the major driver of repeated shifts within species. However, emerging data reveal numerous notable exceptions to these expectations, with recent examples of de novo mutations underpinning convergent shifts among even very closely related lineages, while repetitive sorting processes have occurred among even deeply divergent taxa, sometimes via introgression. A number of very recent analyses have found evidence for both processes occurring on different scales within taxa. We suggest that the relative importance of convergent versus sorting processes depends on the interplay between gene flow among populations, and phylogenetic relatedness of the lineages involved.
Assuntos
Evolução Molecular , Fluxo Gênico , Evolução Biológica , Genoma , Genômica , FilogeniaRESUMO
Natural selection along elevational gradients has potential to drive predictable adaptations across distinct lineages, but the extent of such repeated evolution remains poorly studied for many widespread alpine taxa. We present parallel genomic analyses of two recently evolved flightless alpine insect lineages to test for molecular signatures of repeated alpine adaptation. Specifically, we compare low-elevation vs. alpine stonefly ecotypes from parallel stream populations in which flightless upland ecotypes have been independently derived. We map 67,922 polymorphic genetic markers, generated across 176 Zelandoperla fenestrata specimens from two independent alpine stream populations in New Zealand's Rock and Pillar Range, to a newly developed plecopteran reference genome. Genome-wide scans revealed 31 regions with outlier single nucleotide polymorphisms (SNPs) differentiating lowland vs. alpine ecotypes in Lug Creek, and 37 regions with outliers differentiating ecotypes in Six Mile Creek. Of these regions, 13% (8/60) yielded outlier SNPs across both within-stream ecotype comparisons, implying comparable genomic shifts contribute to this repeated alpine adaptation. Candidate genes closely linked to repeated outlier regions include several with documented roles in insect wing-development (e.g., dishevelled), suggesting that they may contribute to repeated alpine wing reduction. Additional candidate genes have been shown to influence insect fecundity (e.g., ovo) and lifespan (e.g., Mrp4), implying that they might contribute to life history differentiation between upland and lowland ecotypes. Additional outlier genes have potential roles in the evolution of reproductive isolation among ecotypes (hedgehog and Desaturase 1). These results demonstrate how replicated outlier tests across independent lineages can potentially contribute to the discovery of genes underpinning repeated adaptation.
Assuntos
Genoma , Insetos , Animais , Ecótipo , Genômica , Insetos/genética , Neópteros , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
The potential for biological colonization of Antarctic shores is an increasingly important topic in the context of anthropogenic warming. Successful Antarctic invasions to date have been recorded exclusively from terrestrial habitats. While non-native marine species such as crabs, mussels and tunicates have already been reported from Antarctic coasts, none have as yet established there. Among the potential marine invaders of Antarctic shallow waters is Halicarcinus planatus (Fabricius, 1775), a crab with a circum-Subantarctic distribution and substantial larval dispersal capacity. An ovigerous female of this species was found in shallow waters of Deception Island, South Shetland Islands in 2010. A combination of physiological experiments and ecological modelling was used to assess the potential niche of H. planatus and estimate its future southward boundaries under climate change scenarios. We show that H. planatus has a minimum thermal limit of 1°C, and that its current distribution (assessed by sampling and niche modelling) is physiologically restricted to the Subantarctic region. While this species is presently unable to survive in Antarctica, future warming under both 'strong mitigation' and 'no mitigation' greenhouse gas emission scenarios will favour its niche expansion to the Western Antarctic Peninsula (WAP) by 2100. Future human activity also has potential to increase the probability of anthropogenic translocation of this species into Antarctic ecosystems.
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Braquiúros , Animais , Regiões Antárticas , Mudança Climática , Ecossistema , Feminino , HumanosRESUMO
BACKGROUND: Maternal hemorrhage protocols involve risk screening. These protocols prepare clinicians for potential hemorrhage and transfusion in individual patients. Patient-specific estimation and stratification of risk may improve maternal outcomes. STUDY DESIGN AND METHODS: Prediction models for hemorrhage and transfusion were trained and tested in a data set of 74 variables from 63 973 deliveries (97.6% of the source population of 65 560 deliveries included in a perinatal database from an academic urban delivery center) with sufficient data at pertinent time points: antepartum, peripartum, and postpartum. Hemorrhage and transfusion were present in 6% and 1.6% of deliveries, respectively. Model performance was evaluated with the receiver operating characteristic (ROC), precision-recall curves, and the Hosmer-Lemeshow calibration statistic. RESULTS: For hemorrhage risk prediction, logistic regression model discrimination showed ROCs of 0.633, 0.643, and 0.661 for the antepartum, peripartum, and postpartum models, respectively. These improve upon the California Maternal Quality Care Collaborative (CMQCC) accuracy of 0.613 for hemorrhage. Predictions of transfusion resulted in ROCs of 0.806, 0.822, and 0.854 for the antepartum, peripartum, and postpartum models, respectively. Previously described and new risk factors were identified. Models were not well calibrated with Hosmer-Lemeshow statistic P values between .001 and .6. CONCLUSIONS: Our models improve on existing risk assessment; however, further enhancement might require the inclusion of more granular, dynamic data. With the goal of increasing translatability, this work was distilled to an online open-source repository, including a form allowing risk factor inputs and outputs of CMQCC risk, alongside our numerical risk estimation and stratification of hemorrhage and transfusion.
Assuntos
Transfusão de Sangue/estatística & dados numéricos , Modelos Logísticos , Hemorragia Pós-Parto/epidemiologia , Complicações Hematológicas na Gravidez/epidemiologia , Curva ROC , Medição de Risco/métodos , Hemorragia Uterina/epidemiologia , Adulto , Cesárea/estatística & dados numéricos , Bases de Dados Factuais/estatística & dados numéricos , Conjuntos de Dados como Assunto/estatística & dados numéricos , Parto Obstétrico/métodos , Feminino , Humanos , Período Periparto , Hemorragia Pós-Parto/terapia , Gravidez , Complicações na Gravidez/epidemiologia , Complicações Hematológicas na Gravidez/terapia , Utilização de Procedimentos e Técnicas/estatística & dados numéricos , Medição de Risco/estatística & dados numéricos , Fatores de Risco , Fumar/epidemiologia , Hemorragia Uterina/terapiaRESUMO
Anthropogenic environmental change can underpin major shifts in natural selective regimes, and can thus alter the evolutionary trajectories of wild populations. However, little is known about the evolutionary impacts of deforestation-one of the most pervasive human-driven changes to terrestrial ecosystems globally. Absence of forest cover (i.e. exposure) has been suggested to play a role in selecting for insect flightlessness in montane ecosystems. Here, we capitalize on human-driven variation in alpine treeline elevation in New Zealand to test whether anthropogenic deforestation has caused shifts in the distributions of flight-capable and flightless phenotypes in a wing-polymorphic lineage of stoneflies from the Zelandoperla fenestrata species complex. Transect sampling revealed sharp transitions from flight-capable to flightless populations with increasing elevation. However, these phenotypic transitions were consistently delineated by the elevation of local treelines, rather than by absolute elevation, providing a novel example of human-driven evolution in response to recent deforestation. The inferred rapid shifts to flightlessness in newly deforested regions have implications for the evolution and conservation of invertebrate biodiversity.
Assuntos
Ecossistema , Insetos , Animais , Biodiversidade , Conservação dos Recursos Naturais , Florestas , Humanos , Asas de AnimaisRESUMO
Understanding the forces that shape species distributions is increasingly important in a fast-changing world. Although major disturbance events can adversely affect natural populations, they can also present new opportunities, for example by opening up habitat for colonization by other lineages. Following extensive geographic sampling, we use genomic data to infer a range extension following disturbance for an ecologically important intertidal macroalgal species. Specifically, we genotyped 288 southern bull kelp (Durvillaea) plants from 28 localities across central New Zealand. All specimens from the North Island were expected to be D. antarctica, but unexpectedly 10 samples from four sites were identified as D. poha. Extensive sampling from the northern South Island (105 samples at five locations) confirmed the absence of D. poha north of the Kaikoura Peninsula. The North Island specimens of D. poha therefore reveal a biogeographic disjunction, some 150 km northeast of the nearest (South Island) population of this species. Based on strong geographic correspondence between these North Island samples and historic disturbance, we infer that tectonic upheaval, particularly earthquake-generated landslides, likely extirpated local D. antarctica and created an opportunity for a northward range expansion event by D. poha. Close phylogenomic relationships between this new North Island population and South Island samples support a geologically recent northward expansion, rather than a deeper evolutionary origin. These findings indicate the potential of large-scale disturbances to facilitate sudden biogeographic range expansions, and they emphasize the ability of genomic analyses with fine-scale sampling to reveal long-lasting signatures of past disturbance, dispersal, and colonization.