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1.
Mol Ecol ; 32(8): 1860-1874, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36651275

RESUMEN

The iconic Cape buffalo has experienced several documented population declines in recent history. These declines have been largely attributed to the late 19th century rinderpest pandemic. However, the effect of the rinderpest pandemic on their genetic diversity remains contentious, and other factors that have potentially affected this diversity include environmental changes during the Pleistocene, range expansions and recent human activity. Motivated by this, we present analyses of whole genome sequencing data from 59 individuals from across the Cape buffalo range to assess present-day levels of genome-wide genetic diversity and what factors have influenced these levels. We found that the Cape buffalo has high average heterozygosity overall (0.40%), with the two southernmost populations having significantly lower heterozygosity levels (0.33% and 0.29%) on par with that of the domesticated water buffalo (0.29%). Interestingly, we found that these lower levels are probably due to recent inbreeding (average fraction of runs of homozygosity 23.7% and 19.9%) rather than factors further back in time during the Pleistocene. Moreover, detailed investigations of recent demographic history show that events across the past three centuries were the main drivers of the exceptional loss of genetic diversity in the southernmost populations, coincident with the onset of colonialism in the southern extreme of the Cape buffalo range. Hence, our results add to the growing body of studies suggesting that multiple recent human-mediated impacts during the colonial period caused massive losses of large mammal abundance in southern Africa.


Asunto(s)
Genética de Población , Peste Bovina , Animales , Humanos , Sudáfrica , Variación Genética , Búfalos/genética , Colonialismo
2.
Colorectal Dis ; 25(7): 1392-1402, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37020396

RESUMEN

AIM: Dissection in the mesocolic plane is considered by some medical professionals to be crucial in complete mesocolic excision. We aimed to assess whether intramesocolic plane dissection is associated with a risk of recurrence after complete mesocolic excision for right-sided colon cancer. METHOD: This is a single-centre study based on prospectively registered data on patients undergoing resection for Union for International Cancer Control Stage I-III right-sided colon adenocarcinoma during the period 2010-2017. Patients were stratified in an intramesocolic plane group or a mesocolic plane group based on a prospective assessment of fresh specimens by a pathologist. Primary outcome was the 4.2 year risk of recurrence after inverse probability treatment weighting and competing risk analyses. RESULTS: Of 383 patients, 4 (1%) were excluded as the specimen was assessed as muscularis propria plane, 347 (91.6%) specimens were deemed as mesocolic and 32 (8.4%) as intramesocolic. The 4.2 year cumulative incidence of recurrence after inverse probability treatment weighting was 9.1% (95% CI 6.0%-12.1%) in the mesocolic group compared with 14.0% (3.6%-24.5%) in the intramesocolic group with an absolute risk difference in favour of mesocolic plane dissection of 4.9% (-5.7 to 15.6, p = 0.37). No difference was observed in the risk of local recurrence, death before recurrence or overall survival after 4.2 years between the two groups. CONCLUSION: Mesocolic plane dissection can be achieved in more than 90% of patients. The classification seems to be a guide for good surgical practice and not to be used for research purposes.


Asunto(s)
Adenocarcinoma , Neoplasias del Colon , Laparoscopía , Mesocolon , Humanos , Adenocarcinoma/patología , Estudios de Cohortes , Estudios Prospectivos , Neoplasias del Colon/patología , Colectomía/efectos adversos , Mesocolon/cirugía , Mesocolon/patología , Escisión del Ganglio Linfático , Resultado del Tratamiento
3.
Colorectal Dis ; 25(8): 1622-1630, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37353896

RESUMEN

AIM: The German classification system of the completeness of mesocolic excision aims to assess the quality of right-sided colonic cancer surgery by review of photographs. We aimed to validate the reliability of the classification in a clinical context. METHOD: The study was based on a cohort of patients undergoing resection for right-sided colon cancer in two university hospitals served by the same group of pathologists. Prospectively collected photographs of the specimens were assessed twice by six colorectal surgeons to determine the intra-rater and inter-rater accuracy of the German classification and a modification assessing extended right-sided resections. RESULTS: Specimens from 613 resections for right-sided colon cancer were reviewed. Twenty-one specimens were found to be non-assessable, leaving 436 right hemicolectomies, 139 extended right hemicolectomies and 17 right-sided subtotal colectomies. Intra-rater reliability was 0.57-0.74 and weighted kappa coefficients 0.58-0.74, without differences between subgroups. The percentage of agreement between all six participants was 20.3% for all specimens, 21.1% for right hemicolectomy specimens and 18.1% for extended hemicolectomy and right-sided subtotal colectomy specimens. For the right hemicolectomy specimens, the model-based kappa coefficient for agreement was 0.27 (95% CI 0.24-0.30) and for association 0.45 (95% CI 0.41-0.49). CONCLUSION: The German classification of right hemicolectomy specimens showed low intra-rater reliability and inter-rater agreement and association. The use of this classification for scientific purposes appeared not to be reliable.


Asunto(s)
Neoplasias del Colon , Laparoscopía , Mesocolon , Humanos , Reproducibilidad de los Resultados , Neoplasias del Colon/cirugía , Colectomía , Escisión del Ganglio Linfático , Mesocolon/cirugía
4.
Dis Colon Rectum ; 65(5): 683-691, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-34933419

RESUMEN

BACKGROUND: The prognostic value of the present definition of microradicality in colon cancer is poorly understood, especially considering the vast influence it has in rectal cancer prognosis. OBJECTIVE: This study aimed to investigate whether the risk of recurrence after complete mesocolic excision for stage III colon cancer is associated with the distance from tumor tissue to resection margin and whether the location of the involved margin is of any significance. DESIGN: A prospective cohort of patients was stratified into 2 groups to distinguish between direct margin invasion (0-mm resection margin) and a ≤1-mm resection margin without direct invasion or 3 groups to distinguish between the location of margin involvement (lateral tumor resection margin, central vascular ligation margin, and nonperitonealized mesocolic resection margin). Patients with microradical resections were used as a control group. SETTINGS: We included all patients undergoing elective complete mesocolic excision for International Union Against Cancer stage III colon cancer at Nordsjællands Hospital between January 1, 2008, and December 31, 2016. PATIENTS: A total of 276 patients met all inclusion criteria and none of the exclusion criteria. MAIN OUTCOME MEASURES: Primary outcome was risk of recurrence after 3.2 years. RESULTS: A total of 41 patients (15%) had a nonmicroradical resection. The 3.2-year cumulative incidence of recurrence for a 0-mm margin was 43% and 24% for a ≤1-mm margin without direct invasion, corresponding with an HR of 4.3 (p = 0.0146) and 1.3 (p = 0.474). The location of the involved margin showed no significant differences. LIMITATIONS: This was a single-center study containing a limited number of patients with a nonmicroradical resection with a risk of type II error. CONCLUSIONS: We found no increased risk of recurrence for a ≤1-mm margin without direct invasion, indicating that the present classification of microradicality might not be justified if an intact posterior mesocolic fascia without invasion of tumor tissue is present. See Video Abstract at http://links.lww.com/DCR/B625. MARGEN DE RESECCIN NO MICRORRADICAL COMO PREDICTOR DE RECURRENCIA EN PACIENTES CON CNCER DE COLON EN ESTADIO III SOMETIDOS A ESCISIN MESOCLICA COMPLETA UN ESTUDIO DE COHORTE PROSPECTIVO: ANTECEDENTES:El valor pronóstico de la definición actual de microrradicalidad en el cáncer de colon es poco conocido, especialmente considerando la gran influencia que tiene en el pronóstico del cáncer de recto.OBJETIVO:Este estudio tiene como objetivo investigar si el riesgo de recurrencia después de la escisión mesocólica completa (CME) para el cáncer de colon en estadio III está asociado con la distancia desde el tejido tumoral hasta el margen de resección y si la localización del margen afectado tiene alguna importancia.DISEÑO:Una cohorte prospectiva de pacientes se estratificó en dos grupos para distinguir entre la invasión del margen directo (margen de resección de 0 mm) y un margen de resección ≤1 mm sin invasión directa, o tres grupos para distinguir entre la localización de la afectación del margen (resección lateral del margen del tumor, margen de ligadura vascular central y margen de resección mesocólica no peritonizada). Los pacientes con resecciones microrradicales se utilizaron como grupo control.ENTORNO CLÍNICO:Incluimos a todos los pacientes sometidos a CME electiva por cáncer de colon en estadio III de la UICC en el Hospital Nordsjællands, Dinamarca, entre el 1 de enero de 2008 y el 31 de diciembre de 2016.PACIENTES:Un total de 276 pacientes cumplieron todos los criterios de inclusión y ninguno de los criterios de exclusión.PRINCIPALES MEDIDAS DE RESULTADO:El resultado primario fue el riesgo de recurrencia después de 3 · 2 años.RESULTADOS:Un total de 41 (15%) pacientes tuvieron una resección no microrradical. La incidencia acumulada de recurrencia a los 3,2 años para un margen de 0 mm fue del 43% y del 24% para un margen ≤1 mm sin invasión directa, lo que corresponde a un cociente de riesgo de 4,3 (p = 0,0146) y 1,3 (p = 0,474) respectivamente. La localización del margen afectado no mostró diferencias significativas.LIMITACIONES:Estudio unicéntrico con un número limitado de pacientes con resección no microrradical con riesgo de error tipo II.CONCLUSIONES:No encontramos un mayor riesgo de recurrencia para un margen ≤1 mm sin invasión directa, lo que indica que la clasificación actual de microrradicalidad podría no estar justificada si está presente una fascia mesocólica posterior intacta sin invasión del tejido tumoral. Consulte Video Resumen en http://links.lww.com/DCR/B625. (Traducción-Dr Yazmin Berrones-Medina).


Asunto(s)
Neoplasias del Colon , Neoplasias del Recto , Estudios de Cohortes , Neoplasias del Colon/patología , Neoplasias del Colon/cirugía , Humanos , Márgenes de Escisión , Estadificación de Neoplasias , Estudios Prospectivos , Neoplasias del Recto/cirugía , Estudios Retrospectivos
5.
Environ Sci Technol ; 56(23): 17119-17130, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36346717

RESUMEN

Exposure to persistent organic pollutants (POPs) can significantly impact marine mammal health, reproduction, and fitness. This study addresses a significant 20-year gap in gray whale contaminant monitoring through analysis of POPs in 120 blubber biopsies. The scope of this substantial sample set is noteworthy in its range and diversity with collection between 2003 and 2017 along North America's west coast and across diverse sex, age, and reproductive parameters, including paired mothers and calves. Mean blubber concentrations of polychlorinated biphenyls (∑PCBs), dichlorodiphenyltrichloroethanes (∑DDTs), and chlordanes (∑CHLs) generally decreased since previous reports (1968-1999). This is the first report of polybrominated diphenyl ethers (PBDEs) and select hexachlorocyclohexanes (HCHs) in this species. Statistical modeling of the 19 most frequently detected compounds in this dataset revealed sex-, age-, and reproductive status-related patterns, predominantly attributed to maternal offloading. Mean POP concentrations differed significantly by sex in adults (17 compounds, up to 3-fold higher in males) but not in immatures (all 19 compounds). Mean POP concentrations were significantly greater in adults versus immatures in both males (17 compounds, up to 12-fold) and females (13 compounds, up to 3-fold). POP concentrations were detected with compound-specific patterns in nursing calves, confirming maternal offloading for the first time in this species.


Asunto(s)
Bifenilos Policlorados , Contaminantes Químicos del Agua , Animales , Masculino , Femenino , Contaminantes Orgánicos Persistentes , Monitoreo del Ambiente , Ballenas , Contaminantes Químicos del Agua/análisis , Bifenilos Policlorados/análisis , Éteres Difenilos Halogenados/análisis , Tejido Adiposo/química
6.
Int J Equity Health ; 21(1): 109, 2022 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-35978345

RESUMEN

BACKGROUND: For Aboriginal and Torres Strait Islander peoples, culture is foundational to health and wellbeing. However, its inherent conceptual complexity and diversity across and within different Aboriginal and Torres Strait Islander cultural groups means that it has rarely been explored in depth by epidemiological research. As a result, there are very few measures which adequately represent the heterogeneity and importance of Aboriginal and Torres Strait Islander cultures for health and wellbeing. Tools grounded in the social determinants of health are mostly based on European academic opinion about what constitutes culture and wellbeing, and the views of Indigenous peoples are rarely included. Mayi Kuwayu, the National Study of Aboriginal and Torres Strait Islander Wellbeing, developed a new survey tool based on health and wellbeing as perceived by Aboriginal and Torres Strait Islander people. This paper describes several of the key processes used to identify cultural domains and develop questionnaire items for the survey tool, reflecting the importance of culture to Aboriginal and Torres Strait Islander peoples. METHODS: Focus groups were conducted at community organisations and conferences with Aboriginal and Torres Strait Islander people. These sessions were aimed at identifying key cultural domains to be addressed by the Mayi Kuwayu questionnaire and to field test drafts of the questionnaire, which were then modified according to focus group feedback and expert input. RESULTS: Extensive community consultations allowed us to identify key cultural domains, generate questionnaire items, and test initial content validity. The six overarching cultural domains identified during the development of the Mayi Kuwayu questionnaire were: Connection to Country; Beliefs and knowledge; Language; Family, kinship, and community; Cultural expression and continuity; and Self-determination and leadership. CONCLUSIONS: The processes used by Mayi Kuwayu have generated meaningful cultural items for use in Aboriginal and Torres Strait Islander health and wellbeing research. Further assessment of these processes, including a comparison with best practice guidelines and psychometric testing of the items and scales developed, will be conducted in a future program of work.


Asunto(s)
Servicios de Salud del Indígena , Nativos de Hawái y Otras Islas del Pacífico , Grupos Focales , Humanos , Pueblos Indígenas , Grupos Raciales , Encuestas y Cuestionarios
7.
Colorectal Dis ; 24(8): 943-953, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35344254

RESUMEN

AIM: To investigate whether intramesocolic plane dissection assessed on fresh specimens by the pathologist is a risk factor for recurrence after complete mesocolic excision for sigmoid cancer when compared with mesocolic plane dissection. METHOD: Single-centre study based on prospectively registered data on patients undergoing resection for UICC stage I-III sigmoid colon adenocarcinoma during the period 2010-2017. The patients were stratified into either an intramesocolic plane group or a mesocolic plane group. Primary outcome was risk of recurrence after 4.2 years using inverse probability treatment weighting and competing risk analyses. RESULTS: Of a total of 332 patients, two were excluded as the specimen was assessed as muscularis propria plane, 237 (72%) specimens were deemed as mesocolic and 93 (28%) as intramesocolic. The 4.2-year cumulative incidence of recurrence after inverse probability treatment weighting was 14.9% (10.4-19.3) in the mesocolic group compared with 9.4% (3.7-15.0) in the intramesocolic group, thus the absolute risk difference between the mesocolic plane and intramesocolic plane was 5.5% (-12.5-1.6; p = 0.13) in favour of the intramesocolic group. CONCLUSION: Intramesocolic plane dissection was not a risk factor for recurrence after complete mesocolic excision for sigmoid cancer when compared with mesocolic plane dissection. No difference in risk of local recurrence, death before recurrence, and in overall survival after 4.2 years was observed between the two groups. With less than 1% of the specimens deemed as muscularis propria plane dissection, the classification appears unusable for the risk prediction of sigmoid colon cancer.


Asunto(s)
Adenocarcinoma , Neoplasias del Colon , Laparoscopía , Mesocolon , Neoplasias del Colon Sigmoide , Adenocarcinoma/patología , Estudios de Cohortes , Colectomía , Neoplasias del Colon/patología , Humanos , Escisión del Ganglio Linfático , Mesocolon/patología , Mesocolon/cirugía , Neoplasias del Colon Sigmoide/cirugía , Resultado del Tratamiento
8.
BMC Public Health ; 22(1): 1200, 2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35705931

RESUMEN

BACKGROUND: The COVID-19 outbreak has spread to almost every country around the world and caused more than 3 million deaths. The pandemic has triggered enormous disruption in people's daily lives with profound impacts globally. This has also been the case in Australia, despite the country's comparative low mortality and physical morbidity due to the virus. This scoping review aims to provide a broad summary of the research activity focused on mental health during the first 10 months of the pandemic in Australia. RESULTS: A search of the Australian literature was conducted between August-November 2020 to capture published scientific papers, online reports and pre-prints, as well as gaps in research activities. The search identified 228 unique records in total. Twelve general population and 30 subpopulation group studies were included in the review. CONCLUSIONS: Few studies were able to confidently report changes in mental health driven by the COVID-19 context (at the population or sub-group level) due to a lack of pre-COVID comparative data and non-representative sampling. Never-the-less, in aggregate, the findings show an increase in poor mental health over the early period of 2020. Results suggest that young people, those with pre-existing mental health conditions, and the financially disadvantaged, experienced greater declines in mental health. The need for rapid research appears to have left some groups under-researched (e.g. Culturally and Linguistically Diverse populations and Indigenous peoples were not studied), and some research methods under-employed (e.g. there was a lack of qualitative and mixed-methods studies). There is a need for further reviews as the follow-up results of longitudinal studies emerge and understandings of the impact of the pandemic are refined.


Asunto(s)
COVID-19 , Adolescente , Australia/epidemiología , COVID-19/epidemiología , Humanos , Pueblos Indígenas , Salud Mental , Pandemias
9.
J Res Adolesc ; 32(3): 1228-1245, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-34626012

RESUMEN

Although adolescents' perspective on the parent-adolescent relationship uniquely predicts their mental health and wellbeing, there is limited research using qualitative methodologies to explore rich descriptions of adolescents' expectations, attitudes, and beliefs towards parents. The current study qualitatively analyzed adolescent narratives regarding their relationships with their parents. Seventy-two adolescents (68% female; M age = 16.56) provided three-minute speech samples that were examined using thematic analysis to understand key themes in adolescent-parent relationships from adolescents' perspectives. Overall, adolescents valued positive relationships with parents (involving emotional support and companionship), respected their authority, and looked to parents to role-model-valued traits. Mentions of negative interactions were mostly absent or justified as normal. Thus, normative adolescent-parent relationships are largely positive and valued by adolescents.


Asunto(s)
Conducta del Adolescente , Habla , Adolescente , Conducta del Adolescente/psicología , Femenino , Humanos , Relaciones Interpersonales , Masculino , Padres/psicología , Psicología del Adolescente
10.
Harm Reduct J ; 19(1): 127, 2022 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-36403032

RESUMEN

BACKGROUND: This paper explores the feasibility of delivering a music festival-based drug checking service in Australia, evaluating service design and stakeholder acceptability. METHODS: Questionnaire and interview data were collected from adult service users and key stakeholders. A mixed methods approach was used to analyse the data on implementation, impact and acceptability. RESULTS: The trial service tested 170 substances with more than 230 patrons (including individuals who attended in groups). Adult service users had an average age of 21 years. Voluntary participation in the evaluation resulted in 158 participants completing the pre-service questionnaire, most of whom also completed the post-service (147 participants). Eleven in-depth qualitative interviews were conducted with patrons in the weeks following the drug checking. Concordance between what the patron expected the drug to be and drug checking results occurred in 88 per cent (n = 139) of the sample. Evaluation results show that the experience of testing and the accompanying harm reduction brief interventions positively impacted on patrons' self-reported drug harm reduction knowledge, trust of health providers and stated drug use intentions. The service was received positively by service users. CONCLUSION: This is the first independent evaluation of a pilot drug checking service in Australia. Consideration of operational feasibility and self-reported behavioural change suggests that the program was successful, although communication about the interpretation of drug checking results could be improved. Future studies should develop strategies for follow-up and consider the applicability of behavioural change theory.


Asunto(s)
Vacaciones y Feriados , Música , Adulto , Humanos , Adulto Joven , Proyectos Piloto , Australia , Reducción del Daño
11.
Proc Biol Sci ; 288(1961): 20211441, 2021 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-34702080

RESUMEN

More than 25% of species assessed by the International Union for Conservation of Nature (IUCN) are threatened with extinction. Understanding how environmental and biological processes have shaped genomic diversity may inform management practices. Using 68 extant avian species, we parsed the effects of habitat availability and life-history traits on genomic diversity over time to provide a baseline for conservation efforts. We used published whole-genome sequence data to estimate overall genomic diversity as indicated by historical long-term effective population sizes (Ne) and current genomic variability (H), then used environmental niche modelling to estimate Pleistocene habitat dynamics for each species. We found that Ne and H were positively correlated with habitat availability and related to key life-history traits (body mass and diet), suggesting the latter contribute to the overall genomic variation. We found that H decreased with increasing species extinction risk, suggesting that H may serve as a leading indicator of demographic trends related to formal IUCN conservation status in birds. Our analyses illustrate that genome-wide summary statistics estimated from sequence data reflect meaningful ecological attributes relevant to species conservation.


Asunto(s)
Ecosistema , Extinción Biológica , Animales , Aves/genética , Conservación de los Recursos Naturales , Genoma , Genómica
12.
Colorectal Dis ; 23(3): 680-688, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33124132

RESUMEN

AIM: Multidetector computed tomography (MDCT) is the main preoperative decision-making tool in colon cancer treatment, thus the validation of daily clinical practice is warranted. The only published study validating the accuracy of MDCT in a national cohort was performed more than a decade ago. With neoadjuvant chemotherapy for patients with preoperatively assessed locally advanced cancer and the emergence of other personalized treatments we aimed to validate the accuracy of MDCT in a national cohort. METHOD: The study is based on the Danish Colorectal Cancer Group (DCCG) database and included all Danish patients diagnosed with primary colon adenocarcinoma between January 2015 and December 2018. The primary study outcome was the accuracy of MDCT in identifying patients with locally advanced disease. The secondary outcomes were the accuracy of predicting UICC Stage I based on predicting the tumour category (pT3-T4 versus pT1-T2) and lymph node metastasis. RESULTS: A total 3465 patients were included in the analyses regarding locally advanced colon cancer. The sensitivity and specificity were 0.61 (0.58-0.64) and 0.85 (0.83-0.86), respectively, for CT to predict locally advanced disease. The sensitivity and specificity were 0.63 (0.59-0.66) and 0.80 (0.78-0.81), respectively, for predicting UICC Stage I in 4496 patients. Thirty six per cent of the patients assessed as having locally advanced disease and 58% assessed as Stage I were misclassified by MDCT. CONCLUSION: The present standard in Denmark questions whether the implementation of personalized medicine such as neoadjuvant adjuvant chemotherapy and tailor-made resections based on MDCT is justified.


Asunto(s)
Neoplasias del Colon , Tomografía Computarizada Multidetector , Neoplasias del Colon/diagnóstico por imagen , Neoplasias del Colon/patología , Neoplasias del Colon/cirugía , Humanos , Metástasis Linfática , Terapia Neoadyuvante , Estadificación de Neoplasias , Estudios Retrospectivos , Sensibilidad y Especificidad
14.
Mol Ecol ; 28(22): 4914-4925, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31597210

RESUMEN

Genomic diversity is the evolutionary foundation for adaptation to environmental change and thus is essential to consider in conservation planning. Island species are ideal for investigating the evolutionary drivers of genomic diversity, in part because of the potential for biological replicates. Here, we use genome data from 180 individuals spread among 27 island populations from 17 avian species to study the effects of island area, body size, demographic history and conservation status on contemporary genomic diversity. Our study expands earlier work on a small number of neutral loci to the entire genome and from a few species to many. We find significant positive correlation between island size and genomic diversity, a significant negative correlation between body size and genomic diversity, and that historical population declines significantly reduced contemporary genomic diversity. Our study shows that island size is the key factor in determining genomic diversity, indicating that habitat conservation is key to maintaining adaptive potential in the face of global environmental change. We found that threatened species generally had a significantly smaller values of Watterson's theta (θW  = 4Ne µ) compared to nonthreatened species, suggesting that θW may be useful as a conservation indicator for at-risk species. Overall, these findings (a) provide biological insights into how genomic diversity scales with ecological, morphological and demographic factors; and (b) illustrate how population genomic data can be leveraged to better inform conservation efforts.


Asunto(s)
Tamaño Corporal/genética , Pinzones/genética , Genoma/genética , Adaptación Fisiológica/genética , Animales , Evolución Biológica , Demografía/métodos , Flujo Génico/genética , Genómica/métodos , Islas
15.
Heredity (Edinb) ; 123(2): 192-201, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30809076

RESUMEN

The fitness consequences of inbreeding and the individual behaviors that prevent its detrimental effects can be challenging to document in wild populations. Here, we use field and molecular data from a 17-year study of banner-tailed kangaroo rats (Dipodomys spectabilis) to quantify the relationship between inbreeding, mate kinship, and lifetime reproductive success. Using a pedigree that was reconstructed using genetic and field data within a Bayesian framework (median probability of parental assignment = 0.92, mean pedigree depth = 6 generations), we estimated both inbreeding coefficients and kinship between individuals that produced offspring (mean inbreeding coefficient = 0.07, mean mate kinship = 0.08). We also used the pedigree, in combination with census data, to generate a series of fitness estimates, ranging from survival to reproductive maturity to lifetime reproductive success. We found that the population's inbreeding load was low to moderate (0.98-4.66 haploid lethal equivalents) and increased with the time frame over which fitness was estimated (lowest for survival to maturity, highest for adult-to-adult reproductive success). Fitness decreased with increasing inbreeding coefficients. For example, lifetime reproductive success was reduced by 24% for individuals with inbreeding coefficients greater than twice the population mean. Within full sibling pairs, the sibling with less-related mates produced an average of 30% more offspring over its lifetime. These data further illustrate that inbreeding can have a negative effect on lifetime reproductive success.


Asunto(s)
Depresión Endogámica/genética , Depresión Endogámica/fisiología , Reproducción/genética , Reproducción/fisiología , Animales , Teorema de Bayes , Femenino , Aptitud Genética/genética , Aptitud Genética/fisiología , Endogamia/métodos , Masculino , Linaje , Ratas
16.
BMC Evol Biol ; 18(1): 87, 2018 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-29879895

RESUMEN

BACKGROUND: Commercial whaling caused extensive demographic declines in many great whale species, including gray whales that were extirpated from the Atlantic Ocean and dramatically reduced in the Pacific Ocean. The Eastern Pacific gray whale has recovered since the 1982 ban on commercial whaling, but the Western Pacific gray whale-once considered possibly extinct-consists of only about 200 individuals and is considered critically endangered by some international authorities. Herein, we use whole-genome sequencing to investigate the demographic history of gray whales from the Pacific and use environmental niche modelling to make predictions about future gene flow. RESULTS: Our sequencing efforts and habitat niche modelling indicate that: i) western gray whale effective population sizes have declined since the last glacial maximum; ii) contemporary gray whale genomes, both eastern and western, harbor less autosomal nucleotide diversity than most other marine mammals and megafauna; iii) the extent of inbreeding, as measured by autozygosity, is greater in the Western Pacific than in the Eastern Pacific populations; and iv) future climate change is expected to open new migratory routes for gray whales. CONCLUSION: Our results indicate that gray whale genomes contain low nucleotide diversity and have been subject to both historical and recent inbreeding. Population sizes over the last million years likely peaked about 25,000 years before present and have declined since then. Our niche modelling suggests that novel migratory routes may develop within the next century and if so this could help retain overall genetic diversity, which is essential for adaption and successful recovery in light of global environmental change and past exploitation.


Asunto(s)
Genoma , Ballenas/genética , Ballenas/fisiología , Animales , Océano Atlántico , Secuencia de Bases , Análisis por Conglomerados , Ecosistema , Variación Genética , Geografía , Homocigoto , Endogamia , Océano Pacífico , Densidad de Población , Estadística como Asunto
17.
Biol Lett ; 14(10)2018 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-30305459

RESUMEN

Gray whales (Eschrichtius robustus) in the Western Pacific are critically endangered, whereas in the Eastern Pacific, they are relatively common. Holocene environmental changes and commercial whaling reduced their numbers, but gray whales in the Eastern Pacific now outnumber their Western counterparts by more than 100-fold. Herein, we investigate the genetic diversity and population structure within the species using a panel of genic single nucleotide polymorphisms. Results indicate the gray whale gene pool is differentiated into two substocks containing similar levels of genetic diversity, and that both our Eastern and Western geographical samples represent mixed-stock aggregations. Ongoing or future gene flow between the stocks may conserve genetic diversity overall, but admixture has implications for conservation of the critically endangered Western gray whale.


Asunto(s)
Variación Genética , Genética de Población , Ballenas/genética , Migración Animal , Animales , Especies en Peligro de Extinción , Genotipo , Océano Pacífico , Polimorfismo de Nucleótido Simple
18.
Int J Equity Health ; 17(1): 143, 2018 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-30219069

RESUMEN

BACKGROUND: Improving the wellbeing of Indigenous populations is an international priority. Robust research conducted with Aboriginal and Torres Strait Islander peoples is key to developing programs and policies to improve health and wellbeing. This paper aims to quantify the extent of participation in a national longitudinal study of Aboriginal and Torres Strait Islander (Indigenous Australian) children, and to understand the reasons why caregivers participate in the study. METHODS: This mixed methods study uses data from Wave 6 of Footprints in Time, the Longitudinal Study of Indigenous Children. We conducted descriptive analysis of quantitative variables to characterise the sample and retention rates. We applied conventional content analysis to 160 caregivers' open-ended responses to the question, 'Why do you stay in the study?', identifying themes and overarching meta-themes. RESULTS: The study has maintained a high retention rate, with 70.4% (n = 1239/1671) of the baseline sample participating in the study's 6th wave. We identified seven themes related to why participants stay in the study: telling our story, community benefit, satisfaction, tracking Study Child's progress, study processes, receiving study gifts, and valuing what the study stands for. These related to two meta-themes: reciprocity, and trust and connection. Caregivers reported that participation was associated with benefits for their family and community as well as for the study. They identified specific features of the Footprints in Time study design that built and maintained trust and connection between participants and the study. CONCLUSIONS: Our findings support the assertion that Aboriginal and Torres Strait Islander people want to be involved in research when it is done 'the right way'. Footprints in Time has successfully recruited and retained the current-largest cohort of Aboriginal and Torres Strait Islander children in Australia through the use of participatory research methodologies, suggesting effective study implementation and processes. Participants indicated ongoing commitment to the study resulting from perceptions of reciprocity and development of trust in the study. Footprints in Time can serve as a successful model of Aboriginal and Torres Strait Islander health research, to promote good research practice and provides lessons for research with other Indigenous populations.


Asunto(s)
Cuidadores/psicología , Características Culturales , Relaciones Familiares , Servicios de Salud del Indígena/organización & administración , Nativos de Hawái y Otras Islas del Pacífico/psicología , Adulto , Australia , Niño , Femenino , Humanos , Estudios Longitudinales , Masculino , Servicios Urbanos de Salud/organización & administración
19.
Nurs Health Sci ; 17(4): 539-41, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26306397

RESUMEN

In their recent paper on patient experiences of accessing phlebotomy services in hospital outpatient clinics, Clements and colleagues state that there is a real need to better understand the responses of people who inject drugs to phlebotomy. They discuss the reasons why people who inject drugs might not be accessing healthcare services, especially in relation to treatment for hepatitis C. Their research is a welcome addition to the literature that emphasizes the stigma and discrimination faced by people who inject drugs, including within healthcare settings, and outlines the need to promote effective partnerships between healthcare workers and patients so as to deliver the best health outcomes.


Asunto(s)
Hepatitis C/psicología , Flebotomía/psicología , Abuso de Sustancias por Vía Intravenosa/complicaciones , Abuso de Sustancias por Vía Intravenosa/psicología , Femenino , Humanos , Masculino
20.
Biol Lett ; 10(11): 20140619, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25376800

RESUMEN

The Tasmanian devil (Sarcophilus harrisii) was widespread in Australia during the Late Pleistocene but is now endemic to the island of Tasmania. Low genetic diversity combined with the spread of devil facial tumour disease have raised concerns for the species' long-term survival. Here, we investigate the origin of low genetic diversity by inferring the species' demographic history using temporal sampling with summary statistics, full-likelihood and approximate Bayesian computation methods. Our results show extensive population declines across Tasmania correlating with environmental changes around the last glacial maximum and following unstable climate related to increased 'El Niño-Southern Oscillation' activity.


Asunto(s)
Especies en Peligro de Extinción , Variación Genética , Marsupiales/fisiología , Repeticiones de Microsatélite , Animales , Australia , Teorema de Bayes , Marsupiales/genética , Dinámica Poblacional , Factores de Tiempo
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