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1.
Article in English | MEDLINE | ID: mdl-39165168

ABSTRACT

BACKGROUND AND AIM: Inpatients undergoing colonoscopy experience a higher-than-average rate of inadequate bowel preparation (compared to outpatients) leading to canceled procedures, increased stress on the patient, increased time in hospital, and increased cost to the healthcare system. The aim of this scoping review was to identify research surrounding inpatient bowel preparation and to identify modifiable and non-modifiable factors that influence the adequacy of bowel preparation in hospitalized patients undergoing colonoscopy and establish areas where nursing interventions may help improve overall bowel preparation rates. METHODS: An initial search of MEDLINE, CINAHL, Scopus, and Embase was undertaken to identify seed articles, followed by a structured search using keywords and subject headings. Studies conducted between 2000 and 2022 and published in English were included. A total of 37 full-text studies were screened for inclusion, with 22 meeting inclusion criteria. RESULTS: Advanced age, decreased mobility, constipation, extended length of stay, and multiple comorbidities were identified as non-modifiable factors associated with inadequate bowel preparation. Narcotic use, failure to follow preparation instruction, and delayed time to colonoscopy were identified as modifiable factors associated with poor bowel preparation. CONCLUSIONS: Educational interventions and interprofessional programs, using a multifaceted approach, increase the odds of adequate bowel preparation, including nursing tip sheets, troubleshooting flowsheets, and bowel movement assessment scoring.

2.
PNAS Nexus ; 3(8): pgae260, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39108306

ABSTRACT

As on land, oceans exhibit high temporal and spatial temperature variation. This "ocean weather" contributes to the physiological and ecological processes that ultimately determine the patterns of species distribution and abundance, yet is often unrecognized, especially in tropical oceans. Here, we tested the paradigm of temperature stability in shallow waters (<12.5 m) across different zones of latitude. We collated hundreds of in situ, high temporal-frequency ocean temperature time series globally to produce an intuitive measure of temperature variability, ranging in scale from quarter-diurnal to annual time spans. To estimate organismal sensitivity of ectotherms (i.e. microbes, algae, and animals whose body temperatures depend upon ocean temperature), we computed the corresponding range of biological rates (such as metabolic rate or photosynthesis) for each time span, assuming an exponential relationship. We found that subtropical regions had the broadest temperature ranges at time spans equal to or shorter than a month, while temperate and tropical systems both exhibited narrow (i.e. stable) short-term temperature range estimates. However, temperature-dependent biological rates in tropical regions displayed greater ranges than in temperate systems. Hence, our results suggest that tropical ectotherms may be relatively more sensitive to short-term thermal variability. We also highlight previously unexplained macroecological patterns that may be underpinned by short-term temperature variability.

3.
Open Forum Infect Dis ; 11(8): ofae422, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39086466

ABSTRACT

Background: Patients with B-cell lymphoma and acute lymphoblastic leukemia (ALL) who receive chimeric antigen receptor T-cell (CAR-T) therapy may experience clinically significant cytomegalovirus infection (CS-CMVi). However, risk factors for CS-CMVi are not well defined. The aims of our study were to identify risk factors for CS-CMVi and the association between CS-CMVi and nonrelapse mortality (NRM) in lymphoma and ALL patients after CAR-T therapy. Methods: We performed a retrospective single-center cohort analysis of CAR-T recipients between January 2018 and February 2021 for treatment of lymphoma and ALL. We collected data on demographics, oncologic history, CAR-T therapy-related complications, and infectious complications within 1 year of therapy. Results: Of 230 patients identified, 22 (10%) had CS-CMVi. At 1 year following CAR-T therapy, 75 patients (33%) developed relapsed disease and 95 (41%) died; NRM at 1 year was 37%. On Cox regression analysis, Asian or Middle Eastern race (adjusted hazard ratio [aHR], 13.71 [95% confidence interval {CI}, 5.41-34.74]), treatment of cytokine release syndrome/immune effector cell-associated neurotoxicity syndrome with steroids (aHR, 6.25 [95% CI, 1.82-21.47]), lactate dehydrogenase at time of CAR-T therapy (aHR, 1.09 [95% CI, 1.02-1.16]), and CMV surveillance (aHR, 6.91 [95% CI, 2.77-17.25]) were independently associated with CS-CMVi. CS-CMVi was independently associated with NRM at 1 year after CAR-T therapy (odds ratio, 2.49 [95% CI, 1.29-4.82]). Conclusions: Further studies of immunologic correlatives and clinical trials to determine the efficacy of prophylactic strategies are needed to understand the role of CS-CMVi and post-CAR-T mortality.

4.
Front Immunol ; 15: 1413956, 2024.
Article in English | MEDLINE | ID: mdl-38975340

ABSTRACT

Introduction: Younger patients with non-small cell lung cancer (NSCLC) (<50 years) represent a significant patient population with distinct clinicopathological features and enriched targetable genomic alterations compared to older patients. However, previous studies of younger NSCLC suffer from inconsistent findings, few studies have incorporated sex into their analyses, and studies targeting age-related differences in the tumor immune microenvironment are lacking. Methods: We performed a retrospective analysis of 8,230 patients with NSCLC, comparing genomic alterations and immunogenic markers of younger and older patients while also considering differences between male and female patients. We defined older patients as those ≥65 years and used a 5-year sliding threshold from <45 to <65 years to define various groups of younger patients. Additionally, in an independent cohort of patients with NSCLC, we use our observations to inform testing of the combinatorial effect of age and sex on survival of patients given immunotherapy with or without chemotherapy. Results: We observed distinct genomic and immune microenvironment profiles for tumors of younger patients compared to tumors of older patients. Younger patient tumors were enriched in clinically relevant genomic alterations and had gene expression patterns indicative of reduced immune system activation, which was most evident when analyzing male patients. Further, we found younger male patients treated with immunotherapy alone had significantly worse survival compared to male patients ≥65 years, while the addition of chemotherapy reduced this disparity. Contrarily, we found younger female patients had significantly better survival compared to female patients ≥65 years when treated with immunotherapy plus chemotherapy, while treatment with immunotherapy alone resulted in similar outcomes. Discussion: These results show the value of comprehensive genomic and immune profiling (CGIP) for informing clinical treatment of younger patients with NSCLC and provides support for broader coverage of CGIP for younger patients with advanced NSCLC.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Tumor Microenvironment , Humans , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/immunology , Carcinoma, Non-Small-Cell Lung/mortality , Carcinoma, Non-Small-Cell Lung/therapy , Male , Female , Lung Neoplasms/genetics , Lung Neoplasms/immunology , Lung Neoplasms/mortality , Lung Neoplasms/therapy , Middle Aged , Aged , Tumor Microenvironment/immunology , Tumor Microenvironment/genetics , Age Factors , Retrospective Studies , Sex Factors , Adult , Genomics/methods , Biomarkers, Tumor/genetics , Gene Expression Profiling , Immunotherapy
5.
J Addict Nurs ; 35(2): 99-106, 2024.
Article in English | MEDLINE | ID: mdl-38829999

ABSTRACT

ABSTRACT: Few interventions to support smoking cessation include content specifically about diabetes. This is problematic, as people with diabetes face unique challenges when they stop smoking. The purpose of this study was to understand patients' needs and challenges in relation to smoking with Type 2 diabetes and assess the acceptability of a text message intervention to support smoking cessation. People who smoke and have Type 2 diabetes in the United States and the United Kingdom were recruited to participate in semistructured interviews (n = 20), guided by the Capability, Opportunity, Motivation, and Behavior model. A combination of inductive and deductive approaches with framework analysis was used to analyze the data. Results indicated that the participants' experiences related to the constructs of the Capability, Opportunity, Motivation, and Behavior model and the categories of mental health and diabetes distress were also notable parts of their experiences. Results can be used to guide intervention development in this unique group.


Subject(s)
Diabetes Mellitus, Type 2 , Motivation , Qualitative Research , Smoking Cessation , Humans , Diabetes Mellitus, Type 2/psychology , Male , Female , Middle Aged , Smoking Cessation/psychology , United States , Adult , United Kingdom , Aged , Smoking/psychology , Interviews as Topic
7.
Int J Nurs Stud Adv ; 6: 100200, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38746790

ABSTRACT

Background: Across international healthcare systems, healthcare assistant roles have proliferated, in part to decrease nursing costs and support workplace staffing. There is a lack of consensus about the professional title for healthcare assistants, and whether this group requires professional regulation. The variety of terms for healthcare assistants has resulted in confusion around their scope of practice and role within the healthcare team, which may influence patient care. Aim: We aimed to identify the terminology used for healthcare assistants across English speaking countries and determine the international status of professional regulation of healthcare assistants. Method: We conducted a deductive, structured search for healthcare assistant roles that were codified on English-language nursing regulator websites in each jurisdiction in Australia, New Zealand, USA, Canada, Ireland, and the United Kingdom. We assessed what terminology were used for healthcare assistant roles in each area, and whether they were regulated by a professional regulator, such as a college of nursing. Results: Across 77 jurisdictions, we identified 37 different terms for healthcare assistants. The most frequent term was Certified Nurse Aid with 24 uses, and Certified Nursing Assistant with 13 uses. The majority of healthcare assistants are not professionally regulated. Only 12 jurisdictions have professional regulation programs for healthcare assistants, all in the USA. Conclusion: There is an urgent need for international consensus about the nomenclature for healthcare assistants, so the healthcare assistant workforce can be supported, and their work evaluated via research studies. Regulators can consider how to engage with healthcare assistants and protect the public, as healthcare assistants provide an increasing proportion of patient care.

8.
Nat Commun ; 15(1): 3461, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38658590

ABSTRACT

Seismic and mineralogical studies have suggested regions at Earth's core-mantle boundary may be highly enriched in FeO, reported to exhibit metallic behavior at extreme pressure-temperature (P-T) conditions. However, underlying electronic processes in FeO remain poorly understood. Here we explore the electronic structure of B1-FeO at extreme conditions with large-scale theoretical modeling using state-of-the-art embedded dynamical mean field theory (eDMFT). Fine sampling of the phase diagram reveals that, instead of sharp metallization, compression of FeO at high temperatures induces a gradual orbitally selective insulator-metal transition. Specifically, at P-T conditions of the lower mantle, FeO exists in an intermediate quantum critical state, characteristic of strongly correlated electronic matter. Transport in this regime, distinct from insulating or metallic behavior, is marked by incoherent diffusion of electrons in the conducting t2g orbital and a band gap in the eg orbital, resulting in moderate electrical conductivity (~105 S/m) with modest P-T dependence as observed in experiments. Enrichment of solid FeO can thus provide a unifying explanation for independent observations of low seismic velocities and elevated electrical conductivities in heterogeneities at Earth's mantle base.

9.
Sci Rep ; 14(1): 7493, 2024 03 29.
Article in English | MEDLINE | ID: mdl-38553485

ABSTRACT

Among large cetaceans in the Southern Hemisphere, fin whales were the most heavily exploited in terms of numbers taken during the period of intense industrial whaling. Recent studies suggest that, whilst some humpback whale populations in the Southern Hemisphere appears to have almost completely recovered to their estimated pre-whaling abundance, much less is known about the status of Southern Hemisphere fin whales. Circumpolar estimates in the 1990s suggest an abundance of about 5500 animals south of 60° S, while the IDCR/SOWER-2000 survey for the Scotia Sea and Antarctic Peninsula areas estimated 4670 fin whales within this region in the year 2000. More recent studies in smaller regions indicate higher densities, suggesting that previous estimates are overly conservative and/or that fin whales are undergoing a substantial increase. Here we report findings from a recent multi-vessel single-platform sightings survey carried out as part of the 2019 Area 48 Survey for Antarctic krill. While fin whales were encountered throughout the entire survey area, which covered the majority of CCAMLR Management Area 48, they were particularly abundant around the South Orkney Islands and the eastern Bransfield Strait. Large feeding aggregations were also encountered within the central Scotia Sea between South Orkney Islands and South Georgia. Distance sampling analyses suggest an average fin whale density throughout the Scotia Sea of 0.0256 ( CV = 0.149 ) whales per km2, which agrees well with recent density estimates reported from smaller sub-regions within the Scotia Sea. Design-based distance sampling analyses resulted in an estimated total fin whale abundance of 53,873 (CV = 0.15, 95% CI 40,233-72,138), while a density surface model resulted in a slightly lower estimate of 50,837 (CV: 0.136, 95% CI 38,966-66,324). These estimates are at least an order of magnitude greater than the previous estimate from the same region based on the IDCR/SOWER-2000 data, suggesting that fin whales are undergoing a substantial abundance increase in the South Atlantic. This may have important implications for the assessment of cetacean population trends, but also for CCAMLRs spatial overlap analysis process and efforts to implement a Feedback Management system for Antarctic krill. Our abundance estimate suggests an annual summer krill consumption by fin whales in the Antarctic Peninsula and Scotia Sea area of 7.97 (95% CI 4.94-11.91) million tonnes, which would represent around 20 times the total krill catch taken by the commercial fishery in Area 48 in the same season, or about 12.7% of the 2019 summer krill standing stock estimated from data collected during the same survey. This highlights the crucial importance of including cetacean krill predators in assessment and management efforts for living marine resources in the Southern Ocean, and particularly stresses the urgent need for a re-appraisal of abundance, distribution and ecological role of Southern Hemisphere fin whales.


Subject(s)
Euphausiacea , Fin Whale , Humpback Whale , Animals , Seasons , Antarctic Regions
10.
Med Educ Online ; 29(1): 2307715, 2024 Dec 31.
Article in English | MEDLINE | ID: mdl-38320116

ABSTRACT

Teaching and learning of clinical reasoning are core principles of medical education. However, little guidance exists for faculty leaders to navigate curricular transitions between pre-clerkship and clerkship curricular phases. This study compares how educational leaders in these two phases understand clinical reasoning instruction. Previously reported cross-sectional surveys of pre-clerkship clinical skills course directors, and clerkship leaders were compared. Comparisons focused on perceived importance of a number of core clinical reasoning concepts, barriers to clinical reasoning instruction, level of familiarity across the undergraduate medical curriculum, and inclusion of clinical reasoning instruction in each area of the curriculum. Analyses were performed using the Mann Whitney U test. Both sets of leaders rated lack of curricular time as the largest barrier to teaching clinical reasoning. Clerkship leaders also noted a lack of faculty with skills to teach clinical reasoning concepts as a significant barrier (p < 0.02), while pre-clerkship leaders were more likely to perceive that these concepts were too advanced for their students (p < 0.001). Pre-clerkship leaders reported a higher level of familiarity with the clerkship curriculum than clerkship leaders reported of the pre-clerkship curriculum (p < 0.001). As faculty transition students from the pre-clerkship to the clerkship phase, a shared understanding of what is taught and when, accompanied by successful faculty development, may aid the development of longitudinal, milestone-based clinical reasoning instruction.


Subject(s)
Clinical Clerkship , Education, Medical, Undergraduate , Education, Medical , Students, Medical , Humans , Cross-Sectional Studies , Curriculum , Learning , Clinical Reasoning , Clinical Competence
12.
J Adv Nurs ; 80(8): 3432-3441, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38097523

ABSTRACT

BACKGROUND: People who are insecurely housed and use drugs are disproportionately affected by drug poisonings. Nurses are uniquely positioned to utilize harm reduction strategies to address the needs of the whole person. Needle debris encompasses drug paraphernalia discarded in public spaces. Studying needle debris provides a strategic opportunity to identify where drugs are being used and target public health strategies accordingly. AIM: Our aim in this article is to illustrate how spatial video geonarratives (SVG) combined GPS technology interviews, and videos of locations with needle debris, can elicit valuable data for nursing research. METHODS: Using SVG required knowledge of how to collect data wearing cameras and practice sessions were necessary. A Miufly camera worn at waist height on a belt provided the stability to walk while interviewing stakeholders. We wore the cameras and conducted go-along interviews with outreach workers, while filming the built environment. Upon completion of data collection, both the interview and GPS information were analysed using Wordmapper software. CONCLUSIONS: This methodology resulted in data presented uniquely in both a visual map and narrative. These data were richer than if a single modality had been used. These data highlighted specific contextual factors that were related to the location of needle debris, which created opportunities for nursing interventions to support people experiencing vulnerability.


Subject(s)
Ill-Housed Persons , Humans , Geographic Information Systems , Female , Adult , Male , Middle Aged , Nursing Care , Harm Reduction , Video Recording , Substance-Related Disorders/nursing
13.
Nat Commun ; 14(1): 7336, 2023 Nov 13.
Article in English | MEDLINE | ID: mdl-37957142

ABSTRACT

The high-pressure melting curve of FeO controls key aspects of Earth's deep interior and the evolution of rocky planets more broadly. However, existing melting studies on wüstite were conducted across a limited pressure range and exhibit substantial disagreement. Here we use an in-situ dual-technique approach that combines a suite of >1000 x-ray diffraction and synchrotron Mössbauer measurements to report the melting curve for Fe1-xO wüstite to pressures of Earth's lowermost mantle. We further observe features in the data suggesting an order-disorder transition in the iron defect structure several hundred kelvin below melting. This solid-solid transition, suggested by decades of ambient pressure research, is detected across the full pressure range of the study (30 to 140 GPa). At 136 GPa, our results constrain a relatively high melting temperature of 4140 ± 110 K, which falls above recent temperature estimates for Earth's present-day core-mantle boundary and supports the viability of solid FeO-rich structures at the roots of mantle plumes. The coincidence of the defect order-disorder transition with pressure-temperature conditions of Earth's mantle base raises broad questions about its possible influence on key physical properties of the region, including rheology and conductivity.

14.
Front Oncol ; 13: 1225646, 2023.
Article in English | MEDLINE | ID: mdl-37927472

ABSTRACT

Introduction: Next-generation sequencing (NGS) is currently widely used for biomarker studies and molecular profiling to identify concurrent alterations that can lead to the better characterization of a tumor's molecular landscape. However, further evaluation of technical aspects related to the detection of gene rearrangements and copy number alterations is warranted. Methods: There were 12 ALK rearrangement-positive tumor specimens from patients with non-small cell lung cancer (NSCLC) previously detected via fluorescence in situ hybridization (FISH), immunohistochemistry (IHC), and an RNA-based NGS assay, and 26 MET high gene copy number (GCN) cases detected by FISH, selected for this retrospective study. All 38 pre-characterized cases were reassessed utilizing the PGDx™ elio™ tissue complete assay, a 505 gene targeted NGS panel, to evaluate concordance with these conventional diagnostic techniques. Results: The detection of ALK rearrangements using the DNA-based NGS assay demonstrated excellent sensitivity with the added benefit of characterizing gene fusion partners and genomic breakpoints. MET copy number alterations were also detected; however, some discordances were observed likely attributed to differences in algorithm, reporting thresholds and gene copy number state. TMB was also assessed by the assay and correlated to the presence of NSCLC driver alterations and was found to be significantly lower in cases with NGS-confirmed canonical driver mutations compared with those without (p=0.0019). Discussion: Overall, this study validates NGS as an accurate approach for detecting structural variants while also highlighting the need for further optimization to enable harmonization across methodologies for amplifications.

15.
Subst Abuse Treat Prev Policy ; 18(1): 57, 2023 10 04.
Article in English | MEDLINE | ID: mdl-37794482

ABSTRACT

BACKGROUND: The overdose crisis continues across Canada which calls for novel harm reduction strategies. Previous research indicates that a majority of eHealth solutions are cost-effective however current literature on the cost-benefit of eHealth for harm reduction is sparse. The National Overdose Response Service (NORS) is a Canada-wide telephone-based harm reduction service. Service users can call the phone number and connect to a peer who can virtually monitor the substance use session and dispatch appropriate interventions in the case of overdose. OBJECTIVES OF THE RESEARCH/PROJECT: We aim to assess the cost-benefit of NORS by comparing the estimated cost-savings from prevented overdose mortality to the operating costs of the program, alongside healthcare costs associated with its operation. METHODS: Data around systems costs and operational costs were gathered for our calculations. Our primary outcome was cost-benefit ratios, derived from estimates and models of mortality rates in current literature and value of life lost. We presented our main results across a range of values for costs and the probability of death following an unwitnessed overdose. These values were utilized to calculate cost-benefit ratios and value per dollar spent on service provision by NORS over the length of the program's operation (December 2020-2022). RESULTS: Over the total funded lifespan of the program, and using a Monte Carlo estimate, the benefit-to-cost ratio of the NORS program was 8.59 (1.53-15.28) per dollar spent, depending on estimated mortality rates following unwitnessed overdose and program operation costs. Further, we conservatively estimate that early community-based naloxone intervention results in healthcare system savings of $4470.82 per overdose response. CONCLUSIONS: We found the NORS program to have a positive benefit-to-cost ratio when the probability of death following an unwitnessed overdose was greater than 5%. NORS and potentially other virtual overdose monitoring services have the potential to be cost-effective solutions for managing the drug poisoning crisis.


Subject(s)
Drug Overdose , Substance-Related Disorders , Humans , Cost-Benefit Analysis , Naloxone/therapeutic use , Drug Overdose/drug therapy , Delivery of Health Care
18.
J Addict Nurs ; 34(3): 166-172, 2023.
Article in English | MEDLINE | ID: mdl-37669335

ABSTRACT

OBJECTIVE: The aim of this study was to explore client experiences in a community-based injectable opioid agonist therapy (iOAT) program. STUDY SETTING: The study occurred across two cities in Alberta, Canada. STUDY DESIGN: The research team conducted secondary interpretive description analysis on qualitative interview transcripts. DATA COLLECTION: Twenty-three iOAT clients were interviewed as part of a prior quality improvement initiative. Using secondary analysis of the transcripts, interviews were analyzed for themes, to create an understanding of clients' experiences. PRINCIPAL FINDINGS: Participants accessed iOAT through other health services, for treatment of opioid use disorder. Participants reported that building trusting and supportive relationships with nurses was crucial to their success in the program. Through these relationships, participants experienced stopping and starting. They stopped behaviors such as illicit drug use, having withdrawal symptoms and anxiety, and prohibited income generation activities. They started taking care of themselves, accessing housing, increasing financial stability, receiving primary care, and connecting with friends and family. The global experience of iOAT was one of positive change for participants. CONCLUSIONS: The findings of this study are largely consistent with other published examples-iOAT programs create benefits for both clients and their communities. Although clients may join the program to access the hydromorphone, the relationships between staff and clients are the key driver of success.


Subject(s)
Analgesics, Opioid , Opioid-Related Disorders , Humans , Analgesics, Opioid/therapeutic use , Opioid-Related Disorders/drug therapy , Canada , Qualitative Research
19.
Int J Drug Policy ; 120: 104183, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37696136

ABSTRACT

BACKGROUND AND AIMS: Needle debris and discarded drug paraphernalia can pose risks to people who use drugs (PWUD) and other members of the community. The research question guiding our scoping review was, "What is the scope of literature around discussions of and interventions for needle debris associated with drug use in a community setting"? METHODS: The review was guided by the Joanna Briggs Institute methodology. Reporting was in accordance with the PRISMA scoping review extension. Searches in August of 2022 on Medline, CINAHL, PsycINFO, EMBASE, and Social Services Abstracts were completed. Quantitative and qualitative study designs were included. Grey literature was excluded. Extracted data included disposal initiatives and factors influencing disposal practices. RESULTS: The databases combined search total was 3074. A total of 1115 duplicates were removed. Inclusion and exclusion criteria resulted in 72 studies full-text studies reviewed. Nineteen articles met all requirements. Studies from multiple continents resulted in similar themes. Two main themes were identified: needle disposal challenges for PWUD and disposal initiatives. Disposal challenges related to legal barriers and law enforcement influence, the varying definitions of 'safe disposal' and perspectives of PWUD. Disposal initiatives stemmed from community-based initiatives, pharmacy contributions and the perceptions and attitudes of community members. CONCLUSIONS: Needle debris is a complex phenomenon highly impacted by the threat of persecution from law enforcement. PWUD need various disposal methods in proximity to their injecting location to avoid fear of prosecution from residual substances on the syringes.

20.
J Hered ; 114(6): 587-597, 2023 Nov 15.
Article in English | MEDLINE | ID: mdl-37578073

ABSTRACT

The 20th century commercial whaling industry severely reduced populations of great whales throughout the Southern Hemisphere. The effect of this exploitation on genetic diversity and population structure remains largely undescribed. Here, we compare pre- and post-whaling diversity of mitochondrial DNA (mtDNA) control region sequences for 3 great whales in the South Atlantic, such as the blue, humpback, and fin whale. Pre-whaling diversity is described from mtDNA extracted from bones collected near abandoned whaling stations, primarily from the South Atlantic island of South Georgia. These bones are known to represent the first stage of 20th century whaling and thus pre-whaling diversity of these populations. Post-whaling diversity is described from previously published studies reporting large-scale sampling of living whales in the Southern Hemisphere. Despite relatively high levels of surviving genetic diversity in the post-whaling populations, we found evidence of a probable loss of mtDNA lineages in all 3 species. This is evidenced by the detection of a large number of haplotypes found in the pre-whaling samples that are not present in the post-whaling samples. A rarefaction analysis further supports a loss of haplotypes in the South Atlantic humpback and Antarctic blue whale populations. The bones from former whaling stations in the South Atlantic represent a remarkable molecular archive for further investigation of the decline and ongoing recovery in the great whales of the Southern Hemisphere.


Subject(s)
DNA, Mitochondrial , Whales , Animals , Whales/genetics , DNA, Mitochondrial/genetics , Antarctic Regions
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