ABSTRACT
The Montreal Protocol was designed to protect the stratospheric ozone layer by enabling reductions in the abundance of ozone-depleting substances such as chlorofluorocarbons (CFCs) in the atmosphere1-3. The reduction in the atmospheric concentration of trichlorofluoromethane (CFC-11) has made the second-largest contribution to the decline in the total atmospheric concentration of ozone-depleting chlorine since the 1990s 1 . However, CFC-11 still contributes one-quarter of all chlorine reaching the stratosphere, and a timely recovery of the stratospheric ozone layer depends on a sustained decline in CFC-11 concentrations 1 . Here we show that the rate of decline of atmospheric CFC-11 concentrations observed at remote measurement sites was constant from 2002 to 2012, and then slowed by about 50 per cent after 2012. The observed slowdown in the decline of CFC-11 concentration was concurrent with a 50 per cent increase in the mean concentration difference observed between the Northern and Southern Hemispheres, and also with the emergence of strong correlations at the Mauna Loa Observatory between concentrations of CFC-11 and other chemicals associated with anthropogenic emissions. A simple model analysis of our findings suggests an increase in CFC-11 emissions of 13 ± 5 gigagrams per year (25 ± 13 per cent) since 2012, despite reported production being close to zero 4 since 2006. Our three-dimensional model simulations confirm the increase in CFC-11 emissions, but indicate that this increase may have been as much as 50 per cent smaller as a result of changes in stratospheric processes or dynamics. The increase in emission of CFC-11 appears unrelated to past production; this suggests unreported new production, which is inconsistent with the Montreal Protocol agreement to phase out global CFC production by 2010.
ABSTRACT
INTRODUCTION: Enteral feeding prior to cardiac surgery has benefits in pre-operative and post-operative patient statuses. In 2020, to increase pre-operative feeding for single-ventricle patients prior to stage 1 palliation, an enteral feeding algorithm was created. The aim of this study is to monitor the impact of our practice change with the primary outcome of necrotising enterocolitis incidence from birth to 2 weeks following surgical intervention. METHODS: This is a single-site, retrospective cohort study including patients from 1 March, 2018 to 1 July, 2022. Variables assessed include demographics, age at cardiac surgery, primary cardiac diagnosis, necrotising enterocolitis pre-operative and 2 weeks post-operative cardiac surgery, feeding route, feeding type, volume of trophic enteral feeds, and near-infrared spectroscopy. RESULTS: Following implementation of a pre-operative enteral feeding algorithm, the rate of neonates fed prior to surgery increased (39.5-75%, p = .001). The feedings included a mean volume of 28.24 ± 11.16 ml/kg/day, 83% fed breastmilk only, 44.4% tube fed, and 55.5% of infants had all oral feedings. Comparing enterally fed neonates and those not enterally fed, the necrotising enterocolitis incidence from birth to 2 weeks post-op was not significantly increased (p = 0.926). CONCLUSION: As a result of implementing our feeding algorithm, the frequency of infants fed prior to stage I Norwood or Hybrid surgeries increased to 75%, and there was no significant change in the incidence of necrotising enterocolitis. This study confirmed that pre-operative enteral feeds are safe and are not associated with increased incidence of necrotising enterocolitis.
Subject(s)
Enterocolitis, Necrotizing , Fetal Diseases , Univentricular Heart , Infant , Female , Infant, Newborn , Humans , Enteral Nutrition/methods , Retrospective Studies , Enterocolitis, Necrotizing/epidemiology , Enterocolitis, Necrotizing/etiology , Univentricular Heart/complicationsABSTRACT
Since the SARS-CoV-2 pandemic, the potential of exhaled breath (EB) to provide valuable information and insight into the health status of a person has been revisited. Mass spectrometry (MS) has gained increasing attention as a powerful analytical tool for clinical diagnostics of exhaled breath aerosols (EBA) and exhaled breath condensates (EBC) due to its high sensitivity and specificity. Although MS will continue to play an important role in biomarker discovery in EB, its use in clinical setting is rather limited. EB analysis is moving toward online sampling with portable, room temperature operable, and inexpensive point-of-care devices capable of real-time measurements. This transition is happening due to the availability of highly performing biosensors and the use of wearable EB collection tools, mostly in the form of face masks. This feature article will outline the last developments in the field, notably the novel ways of EBA and EBC collection and the analytical aspects of the collected samples. The inherit non-invasive character of the sample collection approach might open new doors for efficient ways for a fast, non-invasive, and better diagnosis.
Subject(s)
COVID-19 , Humans , COVID-19/diagnosis , SARS-CoV-2 , Respiratory Aerosols and Droplets , Biomarkers/analysis , Mass Spectrometry , Breath Tests/methods , ExhalationABSTRACT
PURPOSE: Investigate inhaled nitric oxide's influence on mortality rates, mechanical ventilation and cardiopulmonary bypass duration, and length of stay in the intensive care unit and hospital when administered during cardiopulmonary bypass. METHODS: Following the PRISMA guidelines, we searched four electronic databases (PubMed, EMBASE, Cochrane Library, and Web of Science) up to 4th March 2023. The protocol was registered in the PROSPERO database with ID: CRD42023423007. Using Review Manager software, we reported outcomes as risk ratios (RRs) or mean difference (MD) and confidence intervals (CIs). RESULTS: The meta-analysis included a total of 17 studies with 2897 patients. Overall, there were no significant differences in using nitric oxide over control concerning mortality (RR = 1.03, 95% CI 0.73 to 1.45; P = 0.88) or cardiopulmonary bypass duration (MD = -0.14, 95% CI - 0.96 to 0.69; P = 0.74). The intensive care unit days were significantly lower in the nitric oxide group than control (MD = -0.80, 95% CI - 1.31 to -0.29; P = 0.002). Difference results were obtained in terms of the length of stay in the hospital according to sensitivity analysis (without sensitivity [MD = -0.41, 95% CI - 0.79 to -0.02; P = 0.04] vs. with sensitivity [MD = -0.31, 95% CI - 0.69 to 0.07; P = 0.11]. Subgroup analysis shows that, in children, nitric oxide was favored over control in significantly reducing the duration of mechanical ventilation (MD = -4.58, 95% CI - 5.63 to -3.53; P < 0.001). CONCLUSION: Using inhaled nitric oxide during cardiopulmonary bypass reduces the length of stay in the intensive care unit, and for children, it reduces the duration of mechanical ventilation.
Subject(s)
Cardiopulmonary Bypass , Nitric Oxide , Humans , Child , Adult , Intensive Care Units , Respiration, ArtificialABSTRACT
OBJECTIVE: The aim of this study was to describe the use, duration, and intercenter variation of analgesia and sedation in infants with congenital diaphragmatic hernia (CDH). STUDY DESIGN: This is a retrospective analysis of analgesia, sedation, and neuromuscular blockade use in neonates with CDH. Patient data from 2010 to 2016 were abstracted from the Children's Hospitals Neonatal Database and linked to the Pediatric Health Information System. Patients were excluded if they also had non-CDH conditions likely to affect the use of the study medications. RESULTS: A total of 1,063 patients were identified, 81% survived, and 30% were treated with extracorporeal membrane oxygenation (ECMO). Opioid (99.8%), sedative (93.4%), and neuromuscular blockade (87.9%) use was common. Frequency of use was higher and duration was longer among CDH patients treated with ECMO. Unadjusted duration of use varied 5.6-fold for benzodiazepines (median: 14 days) and 7.4-fold for opioids (median: 16 days). Risk-adjusted duration of use varied among centers, and prolonged use of both opioids and benzodiazepines ≥5 days was associated with increased mortality (p < 0.001) and longer length of stay (p < 0.001). Use of sedation or neuromuscular blockade prior to or after surgery was each associated with increased mortality (p ≤ 0.01). CONCLUSION: Opioids, sedatives, and neuromuscular blockade were used commonly in infants with CDH with variable duration across centers. Prolonged combined use ≥5 days is associated with mortality. KEY POINTS: · Use of analgesia and sedation varies across children's hospital NICUs.. · Prolonged opioid and benzodiazepine use is associated with increased mortality.. · Postsurgery sedation and neuromuscular blockade are associated with mortality..
Subject(s)
Analgesia , Hernias, Diaphragmatic, Congenital , Neuromuscular Blockade , Infant, Newborn , Humans , Infant , Child , Hernias, Diaphragmatic, Congenital/therapy , Retrospective Studies , Analgesics, Opioid/therapeutic use , Hypnotics and Sedatives/therapeutic use , BenzodiazepinesABSTRACT
Rechargeable batteries and supercapacitors are currently considered as promising electrochemical energy storage (EES) systems to address the energy and environment issues. Self-supported transition metal (Ni, Co, Mn, Mo, Cu, V)-based materials are promising electrodes for EES devices, which offer highly efficient charge transfer kinetics. This review summarizes the latest development of transition metal-based materials with self-supported structures for EES systems. Special focus has been taken on the synthetic methods, the selection of substrates, architectures and chemical compositions of different self-supported nanoarrays in energy storage systems. Finally, the challenges and opportunities of these materials for future development in this field are briefly discussed. We believe that the advancement in self-supported electrode materials would pave the way towards next-generation EES.
ABSTRACT
High-coverage whole-genome sequence studies have so far focused on a limited number of geographically restricted populations, or been targeted at specific diseases, such as cancer. Nevertheless, the availability of high-resolution genomic data has led to the development of new methodologies for inferring population history and refuelled the debate on the mutation rate in humans. Here we present the Estonian Biocentre Human Genome Diversity Panel (EGDP), a dataset of 483 high-coverage human genomes from 148 populations worldwide, including 379 new genomes from 125 populations, which we group into diversity and selection sets. We analyse this dataset to refine estimates of continent-wide patterns of heterozygosity, long- and short-distance gene flow, archaic admixture, and changes in effective population size through time as well as for signals of positive or balancing selection. We find a genetic signature in present-day Papuans that suggests that at least 2% of their genome originates from an early and largely extinct expansion of anatomically modern humans (AMHs) out of Africa. Together with evidence from the western Asian fossil record, and admixture between AMHs and Neanderthals predating the main Eurasian expansion, our results contribute to the mounting evidence for the presence of AMHs out of Africa earlier than 75,000 years ago.
Subject(s)
Genome, Human/genetics , Genomics , Human Migration/history , Racial Groups/genetics , Africa/ethnology , Animals , Asia , Datasets as Topic , Estonia , Europe , Fossils , Gene Flow , Genetics, Population , Heterozygote , History, Ancient , Humans , Native Hawaiian or Other Pacific Islander/genetics , Neanderthals/genetics , New Guinea , Population DynamicsABSTRACT
BACKGROUND: Gestational diabetes mellitus (GDM) is one of the most common medical complications during pregnancy. eHealth technologies are proving to be successful in supporting the self-management of medical conditions. Digital technologies have the potential to improve GDM self-management. OBJECTIVE: The primary objective of this systematic literature review was to identify the views of health professionals (HPs) and women with GDM regarding the use of eHealth for GDM self-management. The secondary objective was to investigate the usability and user satisfaction levels when using these technologies. METHODS: Following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) approach, the search included primary papers in English on the evaluation of technology to support self-management of GDM from January 2008 to September 2021 using MEDLINE, CINAHL, Embase, ACM, and IEEE databases. The lists of references from previous systematic literature reviews, which were related to technology and GDM, were also examined for primary studies. Papers with qualitative, quantitative, and mixed methodologies were included and evaluated. The selected papers were assessed for quality using the Cochrane Collaboration tool, National Institute for Health and Care Excellence clinical guidelines, Critical Appraisal Skills Programme Qualitative Checklist, and McGill University Mixed Methods Appraisal Tool. NVivo (QSR International) was used to extract qualitative data, which were subjected to thematic analysis. Narrative synthesis was used to analyze the quantitative data. RESULTS: A total of 26 papers were included in the review. Of these, 19% (5/26) of studies used quantitative research methodologies, 19% (5/26) used qualitative methods, and 62% (16/26) used mixed methods. In all, 4 themes were identified from the qualitative data: the benefits of using technology, engagement with people via technology, the usability of technology, and discouragement factors for the use of technology. The thematic analysis revealed a vast scope of challenges and facilitators in the use of GDM self-management systems. The challenges included usability aspects of the system, technical problems, data privacy, lack of emotional support, the accuracy of reported data, and adoption of the system by HPs. Convenience, improved GDM self-management, peer support, increased motivation, increased independence, and consistent monitoring were facilitators to use these technologies. Quantitative data showed that there is potential for improving the usability of the GDM self-management systems. It also showed that convenience, usefulness, increasing motivation for GDM self-management, helping with GDM self-management, and being monitored by HPs were facilitators to use the GDM self-management systems. CONCLUSIONS: This novel systematic literature review shows that HPs and women with GDM encountered some challenges in using GDM self-management systems. The usability of GDM systems was the primary challenge derived from qualitative and quantitative results, with convenience, consistent monitoring, and optimization of GDM self-management emerging as important facilitators.
Subject(s)
Diabetes, Gestational , Self-Management , Telemedicine , Pregnancy , Female , Humans , Diabetes, Gestational/therapy , Health PersonnelABSTRACT
OBJECTIVE: Infants with congenital diaphragmatic hernia (CDH) require multiple invasive interventions carrying inherent risks, including central venous and arterial line placement. We hypothesized that specific clinical or catheter characteristics are associated with higher risk of nonelective removal (NER) due to complications and may be amenable to efforts to reduce patient harm. STUDY DESIGN: Infants with CDH were identified in the Children's Hospital's Neonatal Database (CHND) from 2010 to 2016. Central line use, duration, and complications resulting in NER are described and analyzed by extracorporeal membrane oxygenation (ECMO) use. RESULTS: A total of 1,106 CDH infants were included; nearly all (98%) had a central line placed, (average of three central lines) with a total dwell time of 22 days (interquartile range [IQR]: 14-39). Umbilical arterial and venous lines were most common, followed by extremity peripherally inserted central catheters (PICCs); 12% (361/3,027 central lines) were removed secondary to complications. Malposition was the most frequent indication for NER and was twice as likely in infants with intrathoracic liver position. One quarter of central lines in those receiving ECMO was placed while receiving this therapy. CONCLUSION: Central lines are an important component of intensive care for infants with CDH. Careful selection of line type and location and understanding of common complications may attenuate the need for early removal and reduce risk of infection, obstruction, and malposition in this high-risk group of patients. KEY POINTS: · Central line placement near universal in congenital diaphragmatic hernia infants.. · Mean of three lines placed per patient; total duration 22 days.. · Clinical patient characteristics affect risk..
Subject(s)
Catheterization, Central Venous , Catheterization, Peripheral , Central Venous Catheters , Extracorporeal Membrane Oxygenation , Hernias, Diaphragmatic, Congenital , Catheterization, Central Venous/adverse effects , Child , Extracorporeal Membrane Oxygenation/adverse effects , Extracorporeal Membrane Oxygenation/methods , Hernias, Diaphragmatic, Congenital/complications , Hernias, Diaphragmatic, Congenital/therapy , Humans , Infant , Infant, Newborn , Retrospective StudiesABSTRACT
The past years have seen the rise of genomic biobanks and mega-scale meta-analysis of genomic data, which promises to reveal the genetic underpinnings of health and disease. However, the over-representation of Europeans in genomic studies not only limits the global understanding of disease risk but also inhibits viable research into the genomic differences between carriers and patients. Whilst the community has agreed that more diverse samples are required, it is not enough to blindly increase diversity; the diversity must be quantified, compared and annotated to lead to insight. Genetic annotations from separate biobanks need to be comparable and computable and to operate without access to raw data due to privacy concerns. Comparability is key both for regular research and to allow international comparison in response to pandemics. Here, we evaluate the appropriateness of the most common genomic tools used to depict population structure in a standardized and comparable manner. The end goal is to reduce the effects of confounding and learn from genuine variation in genetic effects on phenotypes across populations, which will improve the value of biobanks (locally and internationally), increase the accuracy of association analyses and inform developmental efforts.
Subject(s)
Biological Specimen Banks , Pandemics , Genetics, Population , Humans , PrivacyABSTRACT
OBJECTIVE: Doctors working in palliative care services are exposed to challenging emotional environments almost daily. Strong-emotional reactions experienced in this setting have implications for patient care and doctor wellbeing. Existing research has not focused on doctors working in specialist palliative care. This study aimed to understand what strong emotional reactions are experienced by doctors working in specialist palliative care, the cause of these strong emotional reactions and the impact they have on the lives of palliative care doctors. METHODS: Qualitative descriptive design included grounded theory techniques. Semi-structured, audio-recorded individual interviews explored doctors' memories of strong emotional reactions and challenging aspects in palliative care work, how emotions were managed and affected doctors' lives. SETTING/PARTICIPANTS: Twenty doctors were recruited from a specialist palliative care service within a public health network in Melbourne, Australia, comprising of two inpatient units, a consult service and outpatient clinic. RESULTS: Palliative care doctors experience a myriad of strong emotions in their line of work. Experiences found to elicit strong emotional reactions included patient, family and staff distress and organizational issues. Strong emotional reactions impacted clinical behaviours, patient care and doctors' personal lives. Strategies developed for managing strong emotional reactions included debrief, setting boundaries, avoidance and self-reflection, along with non-work strategies such as time with family. CONCLUSIONS: Whilst emotionally challenging experiences are unavoidable and necessary in a palliative care doctor's development, doctors need to be supported to avoid adversely impacting patient care or their own wellbeing.
Subject(s)
Hospice and Palliative Care Nursing , Physicians , Emotions , Humans , Palliative Care , Qualitative ResearchABSTRACT
Aluminum monochloride (AlCl) has been proposed as a promising candidate for laser cooling to ultracold temperatures, and recent spectroscopy results support this prediction. It is challenging to produce large numbers of AlCl molecules because it is a highly reactive open-shell molecule and must be generated in situ. Here we show that pulsed-laser ablation of stable, non-toxic mixtures of Al with alkali or alkaline earth chlorides, denoted XCln, can provide a robust and reliable source of cold AlCl molecules. Both the chemical identity of XCln and the Al : XCln molar ratio are varied, and the yield of AlCl is monitored using absorption spectroscopy in a cryogenic gas. For KCl, the production of Al and K atoms was also monitored. We model the AlCl production in the limits of nonequilibrium recombination dominated by first-encounter events. The non-equilibrium model is in agreement with the data and also reproduces the observed trend with different XCln precursors. We find that AlCl production is limited by the solid-state densities of Al and Cl atoms and the recondensation of Al atoms in the ablation plume. We suggest future directions for optimizing the production of cold AlCl molecules using laser ablation.
ABSTRACT
OBJECTIVES: Intracapsular tonsillectomy (ICT) is increasingly adopted by paediatric centres worldwide due to its association with reduced pain, fast recovery and low risks of post-operative complications. Questions still surround its role in patients with recurrent tonsillitis, as well as tonsillar regrowth requiring revision surgery. DESIGN: Prospective consecutive case series from March 2013 to April 2020. SETTING: Tertiary paediatric ENT referral centre. PARTICIPANTS: Paediatric patients undergoing Coblation ICT, with or without adenoidectomy, for obstructive and/or infective indications. MAIN OUTCOME MEASURES: Health-Related Quality of Life (HRQL), analgesia requirement, post-operative haemorrhage rates, time to return to normal diet and activity or school/nursery, and parental satisfaction. We report revision surgery rates and identify predictive factors for revision surgery. RESULTS: A total of 1257 patients (median age 4.2 years) underwent Coblation ICT, with a median direct and implied follow-up of 101.5 and 1419 days, respectively. We noted significantly improved HRQL scores across all domains. Median analgesia requirement was six days, and no patients required a return to theatre for post-operative haemorrhage. The majority of patients were eating a normal diet within 24 hours and returned to normal activity/school within a week post-operatively. Revision surgery was required in 2.6% of cases, mainly due to recurrent obstructive symptoms from tonsillar regrowth. Being under two years old at initial surgery (OR 5.10), having severe OSA (OR 4.43) or severe comorbidities (OR 2.98) increased the risk of needing revision surgery. CONCLUSIONS: Long-term data demonstrate the efficacy and safety of Coblation ICT in paediatric patients across a range of indications.
Subject(s)
Pain, Postoperative/drug therapy , Postoperative Complications/etiology , Quality of Life , Tonsillectomy/methods , Tonsillitis/surgery , Adolescent , Analgesia , Child , Child, Preschool , Female , Follow-Up Studies , Humans , Infant , Male , Postoperative Complications/therapy , Prospective Studies , ReoperationABSTRACT
In the original article publication, there is an incorrect impression that Fig. 1 formed a formal Directed Acyclic Graph (DAG) by describing it as a causal model. However, it was not correct if interpreted in this way.
ABSTRACT
Replicable genetic association signals have consistently been found through genome-wide association studies in recent years. The recent dramatic expansion of study sizes improves power of estimation of effect sizes, genomic prediction, causal inference, and polygenic selection, but it simultaneously increases susceptibility of these methods to bias due to subtle population structure. Standard methods using genetic principal components to correct for structure might not always be appropriate and we use a simulation study to illustrate when correction might be ineffective for avoiding biases. New methods such as trans-ethnic modeling and chromosome painting allow for a richer understanding of the relationship between traits and population structure. We illustrate the arguments using real examples (stroke and educational attainment) and provide a more nuanced understanding of population structure, which is set to be revisited as a critical aspect of future analyses in genetic epidemiology. We also make simple recommendations for how problems can be avoided in the future. Our results have particular importance for the implementation of GWAS meta-analysis, for prediction of traits, and for causal inference.
Subject(s)
Algorithms , Biological Specimen Banks/statistics & numerical data , Genetics, Population , Genome-Wide Association Study , Multifactorial Inheritance , Humans , Polymorphism, Single NucleotideABSTRACT
The second-harmonic generation process of a focused laser beam inside a nonlinear crystal is described by the Boyd-Kleinman theory. Calculating the actual conversion efficiency and upconverted power requires the solution to a double integral that is analytically intractable. We provide an expression that predicts the exact gain coefficient within an error margin of less than 2% over several orders of magnitude of the confocal parameter and as a function of the walk-off parameter. Our result allows for readily tuning the beam parameters to optimize the performance of the upconversion process and improve optical system designs.
ABSTRACT
The COVID-19 pandemic has led to many physicians working from home whenever possible. Although the concept of 'remote' patient care has been around for decades, present circumstances have provided a grand impetus in that direction with a view to protecting both patient and caregiver. In this article, we discuss some of the various challenges to moving forward with telemedicine, drawing in part on our own experiences in dealing with the COVID-19 pandemic. Clinical, technical, financial and cultural barriers to telemedicine are identified, along with a discussion concerning anticipated benefits. We conclude that the COVID-19 pandemic will likely forever change how healthcare is conducted as telemedicine figures increasingly prominently in the clinical landscape.
Subject(s)
COVID-19/epidemiology , COVID-19/therapy , Physicians/trends , Telemedicine/methods , Telemedicine/trends , Humans , Physicians/standards , Smartphone/standards , Smartphone/trends , Telemedicine/standards , Wearable Electronic Devices/standards , Wearable Electronic Devices/trendsABSTRACT
Therapeutic hypothermia initiated within 6 hours of birth is currently the standard of care for the management of neonates with hypoxic-ischemic encephalopathy. Neonates undergoing therapeutic hypothermia for hypoxic-ischemic encephalopathy are also at risk for severe respiratory failure and need for extracorporeal life support. The risks and benefits of therapeutic hypothermia for hypoxic-ischemic encephalopathy during extracorporeal life support are still not well defined. We report our experience of a case series of six neonates who underwent therapeutic hypothermia for hypoxic-ischemic encephalopathy during extracorporeal life support. We also report long-term neurodevelopmental follow-up from 6 to 24 months and add to the current body of evidence regarding feasibility, clinical experience, and short-term complications.
Subject(s)
Brain Diseases/therapy , Extracorporeal Membrane Oxygenation/adverse effects , Hypothermia, Induced/methods , Hypoxia-Ischemia, Brain/therapy , Data Collection , Extracorporeal Membrane Oxygenation/methods , Female , Humans , MaleABSTRACT
Powerful approaches to inferring recent or current population structure based on nearest neighbor haplotype "coancestry" have so far been inaccessible to users without high quality genome-wide haplotype data. With a boom in nonmodel organism genomics, there is a pressing need to bring these methods to communities without access to such data. Here, we present RADpainter, a new program designed to infer the coancestry matrix from restriction-site-associated DNA sequencing (RADseq) data. We combine this program together with a previously published MCMC clustering algorithm into fineRADstructure-a complete, easy to use, and fast population inference package for RADseq data (https://github.com/millanek/fineRADstructure; last accessed February 24, 2018). Finally, with two example data sets, we illustrate its use, benefits, and robustness to missing RAD alleles in double digest RAD sequencing.
Subject(s)
Genomics/methods , Software , Alleles , Caryophyllaceae/genetics , Population , Sequence Analysis, DNAABSTRACT
Hemocyanin is the primary respiratory protein for the majority of the Mollusca and therefore directly interfaces with the physiological requirements of each species and the environments to which they are adapted. Hemocyanin is therefore likely to have been evolutionarily imprinted by significant habitat shifts. In the gastropod clade Panpulmonata (>30,000 species) major realm transitions have occurred multiple times independently and may have contributed to the diversification of this group. Yet, little is known about the adaptive changes linked to these habitat shifts. In order to gain deeper insight into the evolution of panpulmonate hemocyanins and to infer possible impacts associated with those scenarios, we have assembled and analysed hemocyanin isoforms from 4 panpulmonate species: (i) Helix pomatia, (ii) Cantareus aspersus (both Helicidae, Stylommatophora), (iii) Arion vulgaris (Arionidae, Stylommatophora) and (iv) Lymnaea stagnalis (Lymnaeidae, Hygrophila). Additionally, we describe a new hemocyanin isoform within the genome of the euopisthobranch Aplysia californica. Using these newly acquired hemocyanin data, we performed a phylogenetic analysis that reveals independent duplication events of hemocyanin within lineages that correlate with significant habitat shifts.