Background: The presence of perfluorooctanesulfonate (PFOS), perfluorohexanesulfonate (PFHS), and perfluorooctanoate (PFOA) has been reported in humans and wildlife. Pharmacokinetic differences have ...been observed in laboratory animals. Objective: The purpose of this observational study was to estimate the elimination half-life of PFOS, PFHS, and PFOA from human serum. Methods: Twenty-six (24 male, 2 female) retired fluorochemical production workers, with no additional occupational exposure, had periodic blood samples collected over 5 years, with serum stored in plastic vials at$-80\textdegree C$. At the end of the study, we used HPLC-mass spectrometry to analyze the samples, with quantification based on the ion ratios for PFOS and PFHS and the internal standard$^{18}O_2-PFOS$. For PFOA, quantitation was based on the internal standard$^{13}C_2-PFOA$. Results: The arithmetic mean initial serum concentrations were as follows: PFOS, 799 ng/mL (range, 145-3,490); PFHS, 290 ng/mL (range, 16-1,295); and PFOA, 691 ng/mL (range, 72-5,100). For each of the 26 subjects, the elimination appeared linear on a semi-log plot of concentration versus time; therefore, we used a first-order model for estimation. The arithmetic and geometric mean half-lives of serum elimination, respectively, were 5.4 years 95% confidence interval (CI), 3.9-6.9 and 4.8 years (95% CI, 4.0-5.8) for PFOS; 8.5 years (95% CI, 6.4-10.6) and 7.3 years (95% CI, 5.8-9.2) for PFHS; and 3.8 years (95% CI, 3.1-4.4) and 3.5 years (95% CI, 3.0-4.1) for PFOA. Conclusions: Based on these data, humans appear to have a long half-life of serum elimination of PFOS, PFHS, and PFOA. Differences in species-specific pharmacokinetics may be due, in part, to a saturable renal resorption process.
The Newark–Hartford astrochronostratigraphic polarity timescale (APTS) was developed using a theoretically constant 405-kiloyear eccentricity cycle linked to gravitational interactions with ...Jupiter–Venus as a tuning target and provides a major timing calibration for about 30 million years of Late Triassic and earliest Jurassic time. While the 405-ky cycle is both unimodal and the most metronomic of the major orbital cycles thought to pace Earth’s climate in numerical solutions, there has been little empirical confirmation of that behavior, especially back before the limits of orbital solutions at about 50 million years before present. Moreover, the APTS is anchored only at its younger end by U–Pb zircon dates at 201.6 million years before present and could even be missing a number of 405-ky cycles. To test the validity of the dangling APTS and orbital periodicities, we recovered a diagnostic magnetic polarity sequence in the volcaniclastic-bearing Chinle Formation in a scientific drill core fromPetrified Forest National Park (Arizona) that provides an unambiguous correlation to the APTS. New high precision U–Pb detrital zircon dates from the core are indistinguishable from ages predicted by the APTS back to 215 million years before present. The agreement shows that the APTS is continuous and supports a stable 405-kiloyear cycle well beyond theoretical solutions. The validated Newark–Hartford APTS can be used as a robust framework to help differentiate provinciality from global temporal patterns in the ecological rise of early dinosaurs in the Late Triassic, amongst other problems.
China's Xinjiang Uyghur Autonomous Region has long been a vital link between Europe and Eastern Asia. Xinjiang's geographical location and natural environment have led to unique dietary habits and ...traditions among both the region's modern inhabitants and their ancient forebears. Here, we report on the analysis of human dental residue samples unearthed from the Jiayi Cemetery, a 10th to 2nd century BCE mortuary complex located in the Turpan Basin, Xinjiang, generating ancient starch granules produced by vegetal foodstuffs. Morphological analysis of starch granules and comparative data indicate that crops of Triticeae tribe and subfamily Panicoideae comprised a large portion of the diet, whereas common legumes, nuts, root, and tuber were also present, although in relatively smaller proportions. The discovery of these plant starch granules in archaeological context provides direct evidence of the Jiayi population's vegetal diet and sheds light on agricultural practices during this period. With supporting evidence drawn from zooarchaeological, archaeobotanical, and paleo‐isotopic studies of Bronze Age sites in Xinjiang, we conclude that the people interred in the Jiayi Cemetery practiced cereal crop cultivation and animal husbandry in the Late Bronze and Early Iron Ages. The species of cereal crops represented suggest meaningful economic communication between Central and West Asia.
Previous studies of cause-related marketing (CRM) have demonstrated that it can impact consumer choice. We replicate and extend these findings using choice-based conjoint. Two studies involving 329 ...respondents show that fit between brand and charity can impact choice. In terms of trade-offs against price discounts, donation to a high-fit charity can result in 5–10 times the value of donation to a low-fit charity. We also find, however, that in both studies, the value of CRM does not justify its cost, at least in terms of short-term sales. Implications for the selection of optimal donation levels for CRM campaigns are discussed.
Interest in human exposure to perfluorinated acids, including perfluorobutanesulfonate (PFBS), perfluorohexanesulfonate (PFHS), perfluorooctanesulfonate (PFOS), and perfluorooctanoate (PFOA) has led ...to their measurement in whole blood, plasma and serum. Comparison of measurements in these different blood-based matrices, however, has not been rigorously investigated to allow for across-matrix comparisons. This research evaluated concentrations of PFBS, PFHS, PFOS, and PFOA in whole blood collected in heparin (lithium) and ethylenediamine tetraacetic acid (EDTA), plasma samples collected in heparin and EDTA, and serum (from whole blood allowed to clot). Blood samples were collected from 18 voluntary participants employed at 3M Company. Solid phase extraction methods were used for all analytical sample preparations, and analyses were completed using high-pressure liquid chromatography/tandem mass spectrometry methods. Serum concentrations ranged from: limit of quantitation (LOQ, 5
ng/mL) to 25
ng/mL for PFBS; LOQ (5
ng/mL) to 75
ng/mL for PFHS; LOQ (5
ng/mL) to 880
ng/mL for PFOS; and LOQ (5 or 10
ng/mL) to 7320
ng/mL for PFOA. Values less than the LOQ were not included in the statistical analyses of the mean of the ratios of individual values for the matrices. PFBS was not quantifiable in most samples. Serum to plasma ratios for PFHS, PFOS, and PFOA were 1:1 and this ratio was independent of the level of concentrations measured. Serum or plasma to whole blood ratios, regardless of the anticoagulant used, approximated 2:1. The difference between plasma and serum and whole blood corresponded to volume displacement by red blood cells, suggesting that the fluorochemicals are not found intracellularly or attached to the red blood cells.
Northern East Asia was inhabited by modern humans as early as 40 thousand years ago (ka), as demonstrated by the Tianyuan individual. Using genome-wide data obtained from 25 individuals dated to ...33.6–3.4 ka from the Amur region, we show that Tianyuan-related ancestry was widespread in northern East Asia before the Last Glacial Maximum (LGM). At the close of the LGM stadial, the earliest northern East Asian appeared in the Amur region, and this population is basal to ancient northern East Asians. Human populations in the Amur region have maintained genetic continuity from 14 ka, and these early inhabitants represent the closest East Asian source known for Ancient Paleo-Siberians. We also observed that EDAR V370A was likely to have been elevated to high frequency after the LGM, suggesting the possible timing for its selection. This study provides a deep look into the population dynamics of northern East Asia.
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•Tianyuan/AR33K ancestry was widespread in northern East Asia before the LGM•The earliest northern East Asian appeared in the Amur region at the end of the LGM•The AR14K-related population is the closest East Asian source for Ancient Paleo-Siberians•EDAR V370A likely increased to high frequency after the LGM
Mao et al. demonstrate that the ancestry of the ca. 40 ka individual from Tianyuan Cave near Beijing was widespread geographically and temporally before the Last Glacial Maximum (LGM; ca. 26.5–19 ka). At the end of the LGM, the earliest northern East Asian appeared. After 14 ka, populations in the Amur region comprised the closest East Asian source known for Ancient Paleo-Siberians. Among adaptive genetic variants, EDAR V370A was likely to have been elevated to high frequency after the LGM.
Lost at Sea: Where Is All the Plastic? Thompson, Richard C.; Olsen, Ylva; Mitchell, Richard P. ...
Science (American Association for the Advancement of Science),
05/2004, Letnik:
304, Številka:
5672
Journal Article
Recenzirano
Thompson et al seek to establish that microscopic plastic fragments and fibers are also widespread in the oceans and have accumulated in the pelagic zone and sedimentary habitats. To quantify the ...abundance of microplastics, they collected sediment from beaches and from estuarine and subtidal sediments around Plymouth, UK. To assess the extent of contamination, a further 17 beaches were examined, and similar fibers were found, demonstrating that microscopic plastics are common in sedimentary forms. Their findings demonstrate that the broad spatial extent and accumulation of this type of contamination. Given the rapid increase in plastic production, the longevity of plastic, and the disposable nature of plastic items, the contamination is likely to increase, aside from the potential for plastics to adsorb, release, and transport chemicals. However, it remains to be shown whether toxic substances can pass from plastics to the food chain.
Heart rate variability (HRV) and baroreflex sensitivity (BRS) are indexes reflecting the ability to maintain cardiovascular homeostasis amidst changing conditions. Evidence primarily from small ...studies suggests that both HRV and BRS may be reduced in individuals with chronic pain (CP), with potential implications for cardiovascular risk. We compared HRV and BRS between individuals with CP (broadly defined) and pain-free controls in a large unselected population sample. Participants were 1143 individuals reporting clinically meaningful CP and 5640 pain-free controls who completed a 106-second cold pressor test (CPT). Participants self-reported hypertension status. Resting HRV and BRS were derived from continuous beat-to-beat blood pressure recordings obtained before and after the CPT. Hierarchical regressions for the pre-CPT period indicated that beyond effects of age, sex, and body mass index, the CP group displayed significantly lower HRV in both the time domain (SDNN and rMSSD) and frequency domain (high-frequency HRV power), as well as lower BRS. Results were somewhat weaker for the post-CPT period. Mediation analyses indicated that for 6 of 7 HRV and BRS measures tested, there were significant indirect (mediated) effects of CP status on the presence of comorbid hypertension via reduced HRV or BRS. Results confirm in the largest and broadest sample tested to date that the presence of CP is linked to impaired cardiovascular regulation and for the first time provide support for the hypothesis that links between CP and comorbid hypertension reported in previous population studies may be due in part to CP-related decrements in cardiovascular regulation.
Analgesia and sedation in patients with ARDS Chanques, Gerald; Constantin, Jean-Michel; Devlin, John W. ...
Intensive care medicine,
12/2020, Letnik:
46, Številka:
12
Journal Article
Recenzirano
Odprti dostop
Acute Respiratory Distress Syndrome (ARDS) is one of the most demanding conditions in an Intensive Care Unit (ICU). Management of analgesia and sedation in ARDS is particularly challenging. An expert ...panel was convened to produce a “state-of-the-art” article to support clinicians in the optimal management of analgesia/sedation in mechanically ventilated adults with ARDS, including those with COVID-19. Current ICU analgesia/sedation guidelines promote analgesia first and minimization of sedation, wakefulness, delirium prevention and early rehabilitation to facilitate ventilator and ICU liberation. However, these strategies cannot always be applied to patients with ARDS who sometimes require deep sedation and/or paralysis. Patients with severe ARDS may be under-represented in analgesia/sedation studies and currently recommended strategies may not be feasible. With lightened sedation, distress-related symptoms (e.g., pain and discomfort, anxiety, dyspnea) and patient-ventilator asynchrony should be systematically assessed and managed through interprofessional collaboration, prioritizing analgesia and anxiolysis. Adaptation of ventilator settings (e.g., use of a pressure-set mode, spontaneous breathing, sensitive inspiratory trigger) should be systematically considered before additional medications are administered. Managing the mechanical ventilator is of paramount importance to avoid the unnecessary use of deep sedation and/or paralysis. Therefore, applying an “ABCDEF-R” bundle (R = Respiratory-drive-control) may be beneficial in ARDS patients. Further studies are needed, especially regarding the use and long-term effects of fast-offset drugs (e.g., remifentanil, volatile anesthetics) and the electrophysiological assessment of analgesia/sedation (e.g., electroencephalogram devices, heart-rate variability, and video pupillometry). This review is particularly relevant during the COVID-19 pandemic given drug shortages and limited ICU-bed capacity.
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