11 research outputs found
Time trends and trophic transfer of polybrominated diphenylethers (PBDEs) in Antarctic biota
Polybrominated diphenyl ethers (PBDEs) are âemergedâ contaminants that were produced and used as flame retardants in numerous consumer and industrial applications for decades until banned. They remain ubiquitously present in the environment today. Here, a unique set of \u3e200 biotic samples from the Antarctic was analyzed for PBDEs, including phytoplankton, krill, fish, and fur seal milk, spanning several sampling seasons over 14 years. PBDE-47 and -99 were the dominant congeners determined in all samples, constituting \u3e60% of total PBDEs. A temporal trend was observed for â7PBDE concentrations in fur seal milk, where concentrations significantly increased (R2 = 0.57, p \u3c 0.05) over time (2000â2014). Results for krill and phytoplankton also suggested increasing PBDE concentrations over time. Trends of PBDEs in fur seal milk of individual seals sampled 1 or more years apart showed no clear temporal trends. Overall, there was no indication of PBDEs decreasing in Antarctic biota yet, whereas numerous studies have reported decreasing trends in the northern hemisphere. Similar PBDE concentrations in perinatal versus nonperinatal milk implied the importance of local PBDE sources for bioaccumulation. These results indicate the need for continued assessment of contaminant trends, such as PBDEs, and their replacements, in Antarctica
Trophic position and foraging ecology of Ross, Weddell, and crabeater seals revealed by compound-specific isotope analysis
Ross seals Ommatophoca rossii are one of the least studied marine mammals, with little known about their foraging ecology. Research to date using bulk stable isotope analysis suggests that Ross seals have a trophic position intermediate between that of Weddell Leptonychotes weddellii and crabeater Lobodon carcinophaga seals. However, consumer bulk stable isotope values not only reflect trophic dynamics, but also variations in baseline isotope values, which can be substantial. We used compound-specific isotope analysis of amino acids (CSI-AA) to separate isotopic effects of a shifting baseline versus trophic structure on the foraging ecology of these ecologically important Antarctic pinnipeds. We found that Ross seals forage in an open ocean food web, while crabeater and Weddell seals forage within similar food webs closer to shore. However, isotopic evidence suggests that crabeater seals are likely following sea ice, while Weddell seals target productive areas of the continental shelf of West Antarctica. Our CSI-AA data indicate that Ross seals have a high trophic position equivalent to that of Weddell seals, contrary to prior conclusions from nitrogen isotope results on bulk tissues. CSI-AA indicates that crabeater seals are at a trophic position lower than that of Ross and Weddell seals, consistent with a krill-dominated diet. Our results redefine the view of the trophic dynamics and foraging ecology of the Ross seal, and also highlight the importance of quantifying baseline isotope variations in foraging studies
Carbon and Nitrogen Isoscapes in West Antarctica Reflect Oceanographic Transitions
Antarctic marine ecosystems are spatially and temporally dynamic. Regional climate change is significantly altering the patterns and magnitudes of this dynamism with cascading impacts on biogeochemistry, productivity, and food web architecture. Isoscapes (or isotopic maps) provide a valuable analytical framework to characterize ecosystem processes and address questions about trophic dynamics, animal movement, and elemental cycling. Applications of stable isotope methods to Antarctic ecosystems are currently limited by a paucity of information on geospatial isotope characteristics within the Southern Ocean. In response, we have created the first empirically derived zooplankton isoscapes for West Antarctica based on analysis of bulk nitrogen and carbon isotope values (ÎŽ15N and ÎŽ13C) in 94 zooplankton specimens from the Drake Passage, West Antarctic Peninsula (WAP), and Amundsen and Ross Seas. The zooplankton ÎŽ15N values increased by 3â° from north of the Polar Front (3.3 ± 0.6â°, mean ± SD) to the Ross Sea (6.2 ± 0.8â°), reflecting a productivity gradient across this region. Abundant open water polynyas in the Amundsen and Ross Seas exhibit strong nitrate drawdown, resulting in more 15N-enriched phytoplankton and zooplankton relative to those from the generally less productive WAP and Drake Passage. Zooplankton ÎŽ13C values decreased by 3â° from north of the Polar Front (-24.2 ± 0.9â°) to the Ross Sea (-27.5 ± 1.6â°), likely driven by decreasing sea surface temperatures with increasing latitude. Our isoscapes are a valuable first step in establishing isotopic spatial patterns in West Antarctica and are critical for addressing numerous ecosystem questions
Time Trends of Polybrominated Diphenyl Ethers (PBDEs) in Antarctic Biota
Polybrominated diphenyl
ethers (PBDEs) are âemergedâ contaminants that were
produced
and used as flame retardants in numerous consumer and industrial applications
for decades until banned. They remain ubiquitously present in the
environment today. Here, a unique set of >200 biotic samples from
the Antarctic was analyzed for PBDEs, including phytoplankton, krill,
fish, and fur seal milk, spanning several sampling seasons over 14
years. PBDE-47 and -99 were the dominant congeners determined in all
samples, constituting >60% of total PBDEs. A temporal trend was
observed
for â<sub>7</sub>PBDE concentrations in fur seal milk, where
concentrations significantly increased (<i>R</i><sup>2</sup> = 0.57, <i>p</i> < 0.05) over time (2000â2014).
Results for krill and phytoplankton also suggested increasing PBDE
concentrations over time. Trends of PBDEs in fur seal milk of individual
seals sampled 1 or more years apart showed no clear temporal trends.
Overall, there was no indication of PBDEs decreasing in Antarctic
biota yet, whereas numerous studies have reported decreasing trends
in the northern hemisphere. Similar PBDE concentrations in perinatal
versus nonperinatal milk implied the importance of local PBDE sources
for bioaccumulation. These results indicate the need for continued
assessment of contaminant trends, such as PBDEs, and their replacements,
in Antarctica
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Transfusion-Transmitted Cache Valley Virus Infection in a Kidney Transplant Recipient With Meningoencephalitis.
BackgroundCache Valley virus (CVV) is a mosquito-borne virus that is a rare cause of disease in humans. In the fall of 2020, a patient developed encephalitis 6 weeks following kidney transplantation and receipt of multiple blood transfusions.MethodsAfter ruling out more common etiologies, metagenomic next-generation sequencing (mNGS) of cerebrospinal fluid (CSF) was performed. We reviewed the medical histories of the index kidney recipient, organ donor, and recipients of other organs from the same donor and conducted a blood traceback investigation to evaluate blood transfusion as a possible source of infection in the kidney recipient. We tested patient specimens using reverse-transcription polymerase chain reaction (RT-PCR), the plaque reduction neutralization test, cell culture, and whole-genome sequencing.ResultsCVV was detected in CSF from the index patient by mNGS, and this result was confirmed by RT-PCR, viral culture, and additional whole-genome sequencing. The organ donor and other organ recipients had no evidence of infection with CVV by molecular or serologic testing. Neutralizing antibodies against CVV were detected in serum from a donor of red blood cells received by the index patient immediately prior to transplant. CVV neutralizing antibodies were also detected in serum from a patient who received the co-component plasma from the same blood donation.ConclusionsOur investigation demonstrates probable CVV transmission through blood transfusion. Clinicians should consider arboviral infections in unexplained meningoencephalitis after blood transfusion or organ transplantation. The use of mNGS might facilitate detection of rare, unexpected infections, particularly in immunocompromised patients
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Need for Public Health Messaging Related to Bladder Health from Adolescence to Advanced Age
Objective: The purpose of this analysis was to explore adolescent and adult women's interest in public health messaging around bladder health and perceptions of its usefulness. Materials and Methods: Directed content analysis of focus group data from the Study of Habits, Attitudes, Realities, and Experiences, which explored adolescent and adult women's experiences, perceptions, beliefs, knowledge, and behaviors related to bladder health across the life course. This article reports an analysis of the "Public Health Messaging" code, which included participants' desire or need for information about bladder health and recommendations for appropriate priority audiences. Results: Forty-four focus groups were conducted with 360 participants organized into six age groups (11-93 years). There was consensus across age groups that more information about the bladder is wanted and needed throughout the life course, as there is currently a lack of reliable educational resources. Information on bladder health was seen as useful and important because it enables people to anticipate negative changes in bladder health and act to prevent these. Several priority audiences were identified based on their risk of developing symptoms, but participants also saw value in educating the general public regardless of risk status. They also recommended education for parents and teachers who are in positions to control bathroom access. Conclusions: Results indicate a uniform desire for information on women's bladder health and a need for more research to develop individual prevention strategies and public health messaging for women of all ages, as well as guidance for organizations with a role in supporting bladder health
Correction to: An autosomal dominant neurological disorder caused by de novo variants in FAR1 resulting in uncontrolled synthesis of ether lipids (Genetics in Medicine, (2021), 23, 4, (740-750), 10.1038/s41436-020-01027-3)
In the original author list, Seth Perlmanâs degrees were listed as MD, PhD. Dr Perlmanâs degree is MD. The original version has been corrected