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1.
Trials ; 25(1): 521, 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39095915

RESUMEN

BACKGROUND: Digital technologies, such as wearable devices and smartphone applications (apps), can enable the decentralisation of clinical trials by measuring endpoints in people's chosen locations rather than in traditional clinical settings. Digital endpoints can allow high-frequency and sensitive measurements of health outcomes compared to visit-based endpoints which provide an episodic snapshot of a person's health. However, there are underexplored challenges in this emerging space that require interdisciplinary and cross-sector collaboration. A multi-stakeholder Knowledge Exchange event was organised to facilitate conversations across silos within this research ecosystem. METHODS: A survey was sent to an initial list of stakeholders to identify potential discussion topics. Additional stakeholders were identified through iterative discussions on perspectives that needed representation. Co-design meetings with attendees were held to discuss the scope, format and ethos of the event. The event itself featured a cross-disciplinary selection of talks, a panel discussion, small-group discussions facilitated via a rolling seating plan and audience participation via Slido. A transcript was generated from the day, which, together with the output from Slido, provided a record of the day's discussions. Finally, meetings were held following the event to identify the key challenges for digital endpoints which emerged and reflections and recommendations for dissemination. RESULTS: Several challenges for digital endpoints were identified in the following areas: patient adherence and acceptability; algorithms and software for devices; design, analysis and conduct of clinical trials with digital endpoints; the environmental impact of digital endpoints; and the need for ongoing ethical support. Learnings taken for next generation events include the need to include additional stakeholder perspectives, such as those of funders and regulators, and the need for additional resources and facilitation to allow patient and public contributors to engage meaningfully during the event. CONCLUSIONS: The event emphasised the importance of consortium building and highlighted the critical role that collaborative, multi-disciplinary, and cross-sector efforts play in driving innovation in research design and strategic partnership building moving forward. This necessitates enhanced recognition by funders to support multi-stakeholder projects with patient involvement, standardised terminology, and the utilisation of open-source software.


Asunto(s)
Ensayos Clínicos como Asunto , Determinación de Punto Final , Participación de los Interesados , Humanos , Ensayos Clínicos como Asunto/métodos , Conducta Cooperativa , Comunicación Interdisciplinaria , Aplicaciones Móviles , Dispositivos Electrónicos Vestibles , Proyectos de Investigación , Teléfono Inteligente
2.
Chemosphere ; 358: 142172, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38685322

RESUMEN

In excess of 13,000 chemicals are added to plastics ('additives') to improve performance, durability, and production of plastic products. They are categorized into numerous chemical classes including flame retardants, light stabilizers, antioxidants, and plasticizers. While research on plastic additives in the marine environment has increased over the past decade, there is a lack of methodological standardization. To direct future measurement of plastic additives, we compiled a first-of-its-kind dataset of literature assessing plastic additives in marine environments, delineated by sample type (plastic debris, seawater, sediment, biota). Using this dataset, we performed a meta-analysis to summarize the state of the science. Currently, our dataset includes 217 publications published between 1978 and May 2023. The majority of publications analyzed plastic additives in biota collected from Europe and Asia. Analyses concentrated on plasticizers, brominated flame retardants, and bisphenols. Common sample preparation techniques included Solvent - Agitation extraction for plastic, sediment, and biota samples, and Solid Phase Extraction for seawater samples with dichloromethane and solvent mixtures including dichloromethane as the organic extraction solvent. Finally, most analyses were performed utilizing gas chromatography/mass spectrometry. There are a variety of data gaps illuminated by this meta-analysis, most notably the small number of compounds that have been targeted for detection compared to the large number of additives used in plastic production. The provided dataset facilitates future investigation of trends in plastic additive concentration data in the marine environment (allowing for comparison to toxicity thresholds) and acts as a starting point for optimizing and harmonizing plastic additive analytical methods.


Asunto(s)
Monitoreo del Ambiente , Retardadores de Llama , Plásticos , Contaminantes Químicos del Agua , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Retardadores de Llama/análisis , Monitoreo del Ambiente/métodos , Océanos y Mares , Agua de Mar/química , Plastificantes/análisis , Sedimentos Geológicos/química
3.
Environ Pollut ; 346: 123607, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38382730

RESUMEN

Differential scanning calorimetry (DSC), a routine thermoanalytical method in material science, is gaining utility in plastic pollution research to improve polymer identification. We optimized a DSC method, experimentally testing pan types, temperature ramps, number of melts, and minimum sample masses. Using the optimized method, we created an in-house thermogram library from 201 polymer reference standards. We determined peak melting temperature cutoffs for differentiating variants of PE and nylon. PE cutoffs remained stable after experimentally weathering standards outdoors or for severely weathered HDPE debris found on Hawaii's beaches. Marine debris samples, across a range of weathering severity and previously identified as either low-density or high-density polyethylene (LDPE or HDPE) based on the 1377 cm-1 peak indicating methyl groups by attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR), were analyzed by DSC to confirm or challenge the ATR-FTIR PE differentiation. ATR-FTIR was correct for >80% of the HDPE samples, but <40% of those initially identified as LDPE by ATR-FTIR. Accuracy did not relate to weathering extent. Most samples mis-identified as LDPE were HDPE that had formed methyl groups likely from chain scission during photooxidation. ATR-FTIR alone is unreliable for differentiating weathered PE, DSC is required. We provide a multiple-method workflow for complete and accurate polymer identification, even for microplastics ≥0.03 mg. Applying these methods can better identify the polymer composition of marine debris, essential for sourcing and recycling efforts.


Asunto(s)
Polímeros , Contaminantes Químicos del Agua , Plásticos , Polietileno/análisis , Rastreo Diferencial de Calorimetría , Monitoreo del Ambiente/métodos , Espectroscopía Infrarroja por Transformada de Fourier , Contaminantes Químicos del Agua/análisis
4.
Blood ; 143(16): 1586-1598, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38211335

RESUMEN

ABSTRACT: Maintenance of quiescence and DNA replication dynamics are 2 paradoxical requirements for the distinct states of dormant and active hematopoietic stem cells (HSCs), which are required to preserve the stem cell reservoir and replenish the blood cell system in response to hematopoietic stress, respectively. Here, we show that key self-renewal factors, ß-catenin or Hoxa9, largely dispensable for HSC integrity, in fact, have dual functions in maintaining quiescence and enabling efficient DNA replication fork dynamics to preserve the functionality of hematopoietic stem and progenitor cells (HSPCs). Although ß-catenin or Hoxa9 single knockout (KO) exhibited mostly normal hematopoiesis, their coinactivation led to severe hematopoietic defects stemmed from aberrant cell cycle, DNA replication, and damage in HSPCs. Mechanistically, ß-catenin and Hoxa9 function in a compensatory manner to sustain key transcriptional programs that converge on the pivotal downstream target and epigenetic modifying enzyme, Prmt1, which protects the quiescent state and ensures an adequate supply of DNA replication and repair factors to maintain robust replication fork dynamics. Inactivation of Prmt1 phenocopied both cellular and molecular phenotypes of ß-catenin/Hoxa9 combined KO, which at the same time could also be partially rescued by Prmt1 expression. The discovery of the highly resilient ß-catenin/Hoxa9/Prmt1 axis in protecting both quiescence and DNA replication dynamics essential for HSCs at different key states provides not only novel mechanistic insights into their intricate regulation but also a potential tractable target for therapeutic intervention.


Asunto(s)
Células Madre Hematopoyéticas , beta Catenina , beta Catenina/metabolismo , Células Madre Hematopoyéticas/metabolismo , Ciclo Celular , División Celular , Replicación del ADN
5.
Chemistry ; 30(15): e202303373, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38032346

RESUMEN

A widely utilised class of ligands in synthesis and catalysis, ß-diketiminate (BDI) or NacNac compounds were initially considered innocent in the sense that they remained intact in all their applications. That changed when the γ-C-H unit of their NCCCN backbone was found to engage in reactions with electrophiles. Here, we show that this special reactivity can be used advantageously to prepare tripodal modifications of the common NacNac ligand derived from 2,6-diisopropylphenyl-ß-methyldiketimine [NacNacH (Me, Dipp)]. Lithiation to give NacNacLi, followed by reactions with isocyanates, isothiocyanates and a carbodiimide, have afforded a series of tripodal NacNac variants having N,N,N,O; N,N,N,S; or N,N,N,N potential dentation sites, many of which have been crystallographically characterised. Distinct ligating modes of these new ligands have been elucidated through the crystal structures of their lithiated derivatives.

6.
Mar Pollut Bull ; 198: 115820, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38029668

RESUMEN

Island communities, like the Republic of the Marshall Islands (RMI), depend on marine resources for food and economics, so plastic ingestion by those resources is a concern. The gastrointestinal tracts of nine species of reef fish across five trophic groups (97 fish) were examined for plastics >1 mm. Over 2100 putative plastic particles from 72 fish were identified under light microscopy. Only 115 of these from 47 fish passed a plastic screening method using Fourier-transform infrared microspectroscopy (µFTIR) in reflectance mode. All of these were identified as natural materials in a final confirmatory analysis, attenuated total reflectance FTIR. The high false-positive rate of visual and µFTIR methods highlight the importance of using multiple polymer identification methods. Limited studies on ingested plastic in reef fish present challenging comparisons because of different methods used. No plastic >1 mm were found in the RMI reef fish, reassuring human consumers.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Animales , Humanos , Plásticos/química , Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/análisis , Peces , Micronesia
7.
Cardiol Young ; 34(3): 581-587, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37608743

RESUMEN

OBJECTIVES: Poor oral feeding is a known contributor to growth challenges in neonates with complex CHD who require early surgery. Almost 60% of these infants do not achieve full oral feeding by hospital discharge. This study's objective was to identify predictors of the inability to achieve full oral feeding by discharge in neonates with complex CHD following surgical intervention with cardiopulmonary bypass. STUDY DESIGN: A retrospective analysis of a prospective study of 192 full-term neonates with complex CHD was performed. A stepwise selection logistic regression model was developed to predict oral feeding status at hospital discharge. Univariate subgroup analysis was performed with groups determined based on a CHD classification system. RESULTS: 58% of neonates (112/192) failed to achieve full oral feeding by hospital discharge. A logistic regression model identified duration of deep hypothermic circulatory arrest and reintubation as predictors of the inability to achieve full oral feeding. Among neonates who achieved full oral feeding by discharge (42%), only 7.5% did so after postoperative day 10. Brain maturation, brain injury, and preoperative oral feeding were not predictors of full postoperative oral feeding. CONCLUSIONS: Many infants with CHD fail to achieve full oral feeding by time of hospital discharge. Longer duration of deep hypothermic circulatory arrest and increased number of intubations were predictive of poor feeding after surgery. Prolonging hospitalisation solely to achieve full oral feeding after postoperative day ten is of limited utility; earlier discharge should be promoted to avoid negative impacts on neonatal neurodevelopment as unintended consequences of lengthy hospitalisations.


Asunto(s)
Lesiones Encefálicas , Hospitalización , Lactante , Recién Nacido , Humanos , Estudios Prospectivos , Estudios Retrospectivos , Alta del Paciente
8.
PLoS One ; 18(12): e0295370, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38096183

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0078428.].

9.
Semin Pediatr Neurol ; 47: 101075, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37919030

RESUMEN

BRAIN INJURY DURING TRANSITION IN THE NEWBORN WITH CONGENITAL HEART DISEASE: HAZARDS OF THE PREOPERATIVE PERIOD: Jennifer M. Lynch, J. William Gaynor, Daniel J. Licht Seminars in Pediatric Neurology Volume 28, December 2018, Pages 60-65 Infants born with critical congenital heart disease are at risk for neurodevelopmental morbidities later in life. In-utero differences in fetal circulation lead to vulnerabilities which lead to an increased incidence of stroke, white matter injury, and brain immaturity. Recent work has shown these infants may be most vulnerable to brain injury during the early neonatal period when they are awaiting their cardiac surgeries. Novel imaging and monitoring modalities are being employed to investigate this crucial time period and elucidate the precise timing and cause of brain injury in this population.


Asunto(s)
Lesiones Encefálicas , Cardiopatías Congénitas , Accidente Cerebrovascular , Recién Nacido , Niño , Humanos , Periodo Preoperatorio , Cardiopatías Congénitas/cirugía , Cardiopatías Congénitas/complicaciones , Lesiones Encefálicas/etiología , Encéfalo/anomalías , Accidente Cerebrovascular/complicaciones
10.
Metabolites ; 13(11)2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-37999249

RESUMEN

Cardiopulmonary bypass (CPB) provides cerebral oxygenation and blood flow (CBF) during neonatal congenital heart surgery, but the impacts of CPB on brain oxygen supply and metabolic demands are generally unknown. To elucidate this physiology, we used diffuse correlation spectroscopy and frequency-domain diffuse optical spectroscopy to continuously measure CBF, oxygen extraction fraction (OEF), and oxygen metabolism (CMRO2) in 27 neonatal swine before, during, and up to 24 h after CPB. Concurrently, we sampled cerebral microdialysis biomarkers of metabolic distress (lactate-pyruvate ratio) and injury (glycerol). We applied a novel theoretical approach to correct for hematocrit variation during optical quantification of CBF in vivo. Without correction, a mean (95% CI) +53% (42, 63) increase in hematocrit resulted in a physiologically improbable +58% (27, 90) increase in CMRO2 relative to baseline at CPB initiation; following correction, CMRO2 did not differ from baseline at this timepoint. After CPB initiation, OEF increased but CBF and CMRO2 decreased with CPB time; these temporal trends persisted for 0-8 h following CPB and coincided with a 48% (7, 90) elevation of glycerol. The temporal trends and glycerol elevation resolved by 8-24 h. The hematocrit correction improved quantification of cerebral physiologic trends that precede and coincide with neurological injury following CPB.

11.
Chem Commun (Camb) ; 60(1): 91-94, 2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38019118

RESUMEN

Light alkali metal (Li, Na, K) amides have a long history of synthetic utility, but heavier (Rb, Cs) congeners have barely been studied. This study reveals remarkable structurally complex outcomes of reacting AM(HMDS) (AM = Rb, Cs; HMDS = hexamethyldisilazide) with benzaldehyde and acetophenone. Though complicated, reactions give a diversity of eye-catching isolated products, an enolate with a hexagonal prismatic network, two dienolates with distinct extended ladder motifs, and two ß-imino-alkoxides comprising zig-zag chains of metal-oxygen bonds in infinite cages.

12.
Mar Pollut Bull ; 196: 115585, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37778244

RESUMEN

Abandoned, lost, or discarded fishing gear (ALDFG) is a major source of marine debris with significant ecological and economic consequences. We documented the frequency, types, sizes, and impacts of ALDFG recovered from Hawai'i and Palmyra Atoll in the Central North Pacific Ocean (CNPO) from 2009 to 2021. A total of 253 events weighing 15 metric tons were recovered, including 120 drifting fish aggregating device (dFAD) components, 61 conglomerates, fewer distinct nets, lines, buoys, and unique gear. The Hawaiian Islands were dominated by conglomerates and Palmyra Atoll by dFADs. DFADs were connected to the Eastern Pacific tropical tuna purse seine fishery. Windward O'ahu experienced up to seven events or 1800 kg of ALDFG per month. Across Hawai', ALDFG was present on 55 % of survey days, including hotspots with 100 % occurrence. Coral reef damage, entangled wildlife, navigational and removal costs are reported. The data highlight the large magnitude of ALDFG and associated impacts in the CNPO.


Asunto(s)
Contaminación Ambiental , Caza , Animales , Hawaii , Islas , Océano Pacífico , Explotaciones Pesqueras
13.
J Pers ; 2023 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-37680053

RESUMEN

OBJECTIVE: We investigated how these motivations combined within individuals to form unique profiles, and how these different profiles relate to personality traits and team behaviors. BACKGROUND: Dominance, prestige, and leadership motives each play a key role in shaping social success or failure in gaining social rank and influence. METHOD: We used latent profile analysis across two samples (engineering student project teams, Nstudent = 1088; working adults, Nworker = 466) to identify profile configurations and how such profiles related to important outcomes. RESULTS: We identified qualitatively distinct profiles: ultra-dominance profile (prominent dominance motive with high prestige and leadership motives); prestigious leadership profile (moderately high prestige and leadership motives, low dominance motive); and weak social power motive profile (low on all three motives). Individuals with the prestigious leadership profile were more likely to emerge as leaders, compared to those with a weak social power motive profile. People with an ultra-dominance profile scored higher on narcissism and tended to perceive themselves as leaders, despite not being deemed more leader-like by teammates. CONCLUSION: Using a person-centered approach allowed us to identify three power motive profiles across independent samples and generate insights into how these profiles manifest different social behaviors and outcomes.

14.
Mar Pollut Bull ; 196: 115570, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37776741

RESUMEN

Discarded fishing gear (DFG) comprises most of the plastic in the North Pacific Ocean and causes environmental and economic losses. Building evidence on the material construction of fishing gear types is critical to develop solutions to reduce DFG amounts and impacts. We forensically assessed the construction and chemical composition of eight different gear types removed as DFG around O'ahu, Hawai'i. A thorough dissection and novel analysis was conducted including the documentation of gear constructions, polymer identification using attenuated total reflection-Fourier transform infrared spectroscopy and differential scanning calorimetry, and elemental additive detection using X-ray fluorescence. Twenty-six different polymers were identified, and most gear consisted of polyethylene variants or blends. This inventory of physical and chemical characterization of DFG can help future polymer identification of particular gear types through visual techniques. Additionally, it can aid in identifying sources of these gear types and promote recycling options.


Asunto(s)
Explotaciones Pesqueras , Caza , Hawaii , Océano Pacífico , Polímeros
15.
Front Pediatr ; 11: 1125985, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37425272

RESUMEN

Background: Surgical procedures involving the aortic arch present unique challenges to maintaining cerebral perfusion, and optimal neuroprotective strategies to prevent neurological injury during such high-risk procedures are not completely understood. The use of antegrade cerebral perfusion (ACP) has gained favor as a neuroprotective strategy over deep hypothermic circulatory arrest (DHCA) due to the ability to selectively perfuse the brain. Despite this theoretical advantage over DHCA, there has not been conclusive evidence that ACP is superior to DHCA. One potential reason for this is the incomplete understanding of ideal ACP flow rates to prevent both ischemia from underflowing and hyperemia and cerebral edema from overflowing. Critically, there are no continuous, noninvasive measurements of cerebral blood flow (CBF) and cerebral oxygenation (StO2) to guide ACP flow rates and help develop standard clinical practices. The purpose of this study is to demonstrate the feasibility of using noninvasive, diffuse optical spectroscopy measurements of CBF and cerebral oxygenation during the conduct of ACP in human neonates undergoing the Norwood procedure. Methods: Four neonates prenatally diagnosed with hypoplastic left heart syndrome (HLHS) or a similar variant underwent the Norwood procedure with continuous intraoperative monitoring of CBF and cerebral oxygen saturation (StO2) using two non-invasive optical techniques, namely diffuse correlation spectroscopy (DCS) and frequency-domain diffuse optical spectroscopy (FD-DOS). Changes in CBF and StO2 due to ACP were calculated by comparing these parameters during a stable 5 min period of ACP to the last 5 min of full-body CPB immediately prior to ACP initiation. Flow rates for ACP were left to the discretion of the surgeon and ranged from 30 to 50 ml/kg/min, and all subjects were cooled to 18°C prior to initiation of ACP. Results: During ACP, the continuous optical monitoring demonstrated a median (IQR) percent change in CBF of -43.4% (38.6) and a median (IQR) absolute change in StO2 of -3.6% (12.3) compared to a baseline period during full-body cardiopulmonary bypass (CPB). The four subjects demonstrated varying responses in StO2 due to ACP. ACP flow rates of 30 and 40 ml/kg/min (n = 3) were associated with decreased CBF during ACP compared to full-body CPB. Conversely, one subject with a higher flow6Di rate of 50 ml/kg/min demonstrated increased CBF and StO2 during ACP. Conclusions: This feasibility study demonstrates that novel diffuse optical technologies can be utilized for improved neuromonitoring in neonates undergoing cardiac surgery where ACP is utilized. Future studies are needed to correlate these findings with neurological outcomes to inform best practices during ACP in these high-risk neonates.

16.
Anal Bioanal Chem ; 415(15): 2869-2871, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37233767
17.
Anal Bioanal Chem ; 415(15): 2873-2890, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37036484

RESUMEN

There is growing concern from scientists, policy makers, and the public about the contamination of natural and indoor environments with plastics, particularly micro/nanoplastics. Typically, characterizing microplastics in environmental samples requires extensive sample processing to isolate particles, followed by spectroscopic methodologies to identify particle polymer composition. Spectroscopic techniques are limited in their ability to provide polymer mass or advanced chemical composition (e.g., chemical additive content), which are important for toxicological assessments. To achieve mass fraction quantification and chemical characterization of plastics in environmental samples, many researchers have turned to thermoanalytical spectrometric approaches, particularly pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). Sample preparation for Py-GC/MS may be approached similarly to techniques needed for spectroscopic approaches (e.g., isolate particles on a filter), employ pressurized solvent extraction, or use ultrafiltration techniques to concentrate nanoplastics. Great strides have been made in using calibration curves to quantify plastics in complex matrices. However, the approaches to the pyrolysis thermal program, as well as calibrant and sample preparation, are inconsistent, requiring refinement and harmonization. This review provides a critical synthesis of previous Py-GC/MS work and highlights opportunities for novel and improved Py-GC/MS analysis of plastics in the future.

18.
Pers Soc Psychol Bull ; : 1461672231163645, 2023 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-37013863

RESUMEN

Integrating insights from interdependence theory with the narcissistic admiration and rivalry concept, we propose that a pivotal obstacle for narcissistic leaders is their inability to sustain benevolent perceptions over time. As people strive to interpret social behavior in terms of self- or other-interest, the narcissistic tendency of prioritizing self-interests over the collective may become apparent and eventually taint their reputation as a leader. We examined how interpersonal motive perceptions-based on attributions of self- and other-interest-would clarify the leadership paradox of narcissism. We tracked 472 participants in 119 teams across four time-points. Narcissistic rivalry (but not admiration) corresponded to increasingly negative leader effectiveness ratings. The extent to which individuals were perceived as self-maximizing and lacking concern for other interests was tightly connected to declines in leader effectiveness across time. Altogether, these results offer insight into how perceived interpersonal motives may explain the downfall of narcissistic leadership.

19.
Environ Toxicol Chem ; 42(6): 1309-1325, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36942377

RESUMEN

Vitellogenin (VTG), an egg yolk precursor, is abnormally produced by male and juvenile oviparous species after exposure to estrogens. Plasma VTG in loggerhead sea turtles (Caretta caretta) helped us understand their reproductive maturation and investigate it as a biomarker of contaminant exposure. The presence of VTG was screened in plasma from 404 loggerheads from the northwestern Atlantic Ocean using a freshwater turtle antibody in western blots. The concentrations of VTG were semiquantified using band intensities calibrated to results from a loggerhead antibody enzyme-linked immunoassay. The detection and concentrations of VTG were in (from highest to lowest): nesting females, in-water adult females, subadult females, smaller females, unknown sex, and males. Loggerheads from this region begin vitellogenesis at ≅77 cm straight carapace length. We classified VTG expression as abnormal in nine male or juvenile turtles. Organochlorine contaminant (OC) concentrations were measured in blood and/or fat biopsies of some turtles. One abnormal VTG female had the second highest fat polychlorinated biphenyl (PCB) and 4,4'-dichlorodiphenyldichloroethylene concentrations compared among 43 VTG-negative juveniles. The nine VTG-abnormal turtles had average blood PCB concentrations 8.5% higher, but not significantly different, than 46 VTG-negative juveniles (p = 0.453). In turtles less than 77 cm, blood PCB concentrations were significantly, but weakly, correlated with semiquantified VTG concentrations (tau = 0.1, p = 0.004). Greater blood OC concentrations were found in adult females than in males, which motivated the creation of a conceptual model of OC, VTG, and hormone concentrations across a reproductive cycle. A decision tree is also provided incorporating VTG as a sexing tool. Abnormal VTG expression cannot conclusively be linked to endocrine disruption caused by these OC concentrations. Studies should further investigate causes of abnormal VTG expression in wild sea turtles. Environ Toxicol Chem 2023;42:1309-1325. © 2023 SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.


Asunto(s)
Bifenilos Policlorados , Tortugas , Animales , Femenino , Masculino , Vitelogeninas/metabolismo , Tortugas/metabolismo , Bifenilos Policlorados/metabolismo , Anticuerpos/metabolismo , Estrógenos/metabolismo
20.
Environ Toxicol Chem ; 42(5): 1109-1123, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36866800

RESUMEN

The present study determined if green sea turtles (Chelonia mydas) in Kailua Bay, Oahu, in the Hawaiian Islands have elevated blood and scute lead (Pb), arsenic (As), and antimony (Sb) concentrations resulting from lead deposition at a historic skeet shooting range. Blood and scute samples were collected and analyzed for Pb, As, and Sb via inductively coupled plasma-mass spectrometry. Prey, water, and sediment samples were also analyzed. Turtle samples in Kailua Bay (45) have blood Pb concentrations (328 ± 195 ng/g) greater than a reference population (Howick Group of Islands, 29.2 ± 17.1 ng/g). Compared with other green turtle populations, only turtles in Oman, Brazil, and San Diego, CA have blood Pb concentrations greater than turtles in Kailua Bay. The estimated daily exposure of Pb from algae sources in Kailua Bay (0.12 mg/kg/day) was significantly lower than the no observed adverse effect level (100 mg/kg) of red-eared slider turtles. However, the chronic effects of Pb on sea turtles is poorly understood and continued monitoring of this population will increase our understanding of the Pb and As loads of sea turtles in Kailua Bay. Environ Toxicol Chem 2023;42:1109-1123. © 2023 SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.


Asunto(s)
Arsénico , Metales Pesados , Tortugas , Contaminantes Químicos del Agua , Animales , Hawaii , Plomo/análisis , Contaminantes Químicos del Agua/análisis , Metales Pesados/análisis , Arsénico/análisis
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