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Association of Prenatal Urinary Concentrations of Phthalates and Bisphenol A and Pubertal Timing in Boys and Girls.
BackgroundAnimal studies suggest that phthalates and bisphenol A (BPA), endocrine-disrupting chemicals found in many consumer products, may impact the timing of puberty.ObjectivesWe aimed to determine the association of prenatal exposure to high-molecular-weight phthalates and BPA with pubertal timing in boys and girls participating in the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) longitudinal cohort study.MethodsWe quantified urinary concentrations of eight phthalate metabolites and BPA at two time points during pregnancy among participating mothers ([Formula: see text]) and conducted clinical Tanner staging of puberty on their children every 9 months between 9 and 13 y of age. We conducted accelerated failure time models and examined the role of child overweight/obese status in this association.ResultsThe sum of urinary metabolites of di(2-ethylhexyl) phthalate [Formula: see text], monobenzyl phthalate (MBzP), and BPA were associated with later onset of at least one of the three outcomes assessed in girls (thelarche, pubarche, or menarche) and with earlier onset of at least one of the two outcomes assessed in boys (gondarche and pubarche). We found that monocarboxynonyl phthalate, monocarboxyoctyl phthalate, mono(3-carboxypropyl) phthalate, and BPA were associated with later pubarche and menarche mostly among normal-weight girls but not overweight/obese girls. MBzP was associated with later thelarche in all girls, and [Formula: see text] was associated with later thelarche and menarche in all girls. BPA and all phthalate biomarkers were associated with earlier gonadarche and pubarche in all boys as well as in overweight/obese boys when stratified by weight. Among normal-weight boys, associations with BPA were also inverse, whereas associations with phthalate metabolites were close to the null or positive.ConclusionsSeveral high-molecular-weight phthalates and BPA were associated with later puberty in girls and earlier puberty in boys included in the CHAMACOS cohort study. Childhood overweight/obesity may modify these associations. https://doi.org/10.1289/EHP3424
Changes in Fish Catch Rates in the Presence of Air Gun Sounds in Prudhoe Bay, Alaska
Air guns used in oil industry seismic surveys have the capacity to change fish catch rates, but no previous work has demonstrated this effect in shallow water or in Arctic oilfields. Long-term monitoring of fish catches using four fyke nets allowed assessment of changes in catch rates during a 2014 seismic survey in Prudhoe Bay, Alaska. Fyke net locations were instrumented with both conventional hydrophones and vector sensors. Catch rates were generally within the range of those found in 27 previous sampling seasons. The effect of air guns on eight species was assessed using a modified Before-After/Control-Impact analysis, with historical data and 2014 data as the Before-After components of the analysis and days without and with air gun activity as the Control-Impact components. Results showed significant changes associated with air guns in catch rates at one or more nets at p < 0.1 for all eight species and at p < 0.05 for seven of the eight. Changes included both increased and decreased catch rates, perhaps reflecting displacement of fish in response to air gun sounds throughout the study area. Measured sound pressure levels associated with air gun pulses were low and usually undetectable close to the fyke nets, reflecting the loss of low frequencies in shallow water (~1.5 m). Attempts to measure particle velocities failed when wind-driven surface waves overwhelmed vector sensors. However, fish responses may have been related to changes in particle motion associated with air gun sounds.Les armes Ă air comprimĂ© dont on se sert pour faire les levĂ©s sismiques dans lâindustrie pĂ©troliĂšre ont la capacitĂ© de changer le taux de capture des poissons, mais aucune Ă©tude nâa jamais dĂ©montrĂ© lâeffet de ces armes dans les eaux peu profondes ou dans les champs pĂ©trolifĂšres de lâArctique. La surveillance Ă long terme des prises de poissons Ă lâaide de quatre verveux a permis dâĂ©valuer les changements en matiĂšre de taux de prises pendant un levĂ© sismique qui a eu lieu Ă Prudhoe Bay, Alaska, en 2014. Les emplacements de verveux ont Ă©tĂ© munis dâhydrophones classiques et de capteurs de vecteur. De maniĂšre gĂ©nĂ©rale, les taux de prises coĂŻncidaient avec la gamme rĂ©pertoriĂ©e au cours des 27 saisons dâĂ©chantillonnage prĂ©cĂ©dentes. Lâeffet des armes Ă air comprimĂ© sur huit espĂšces a Ă©tĂ© Ă©valuĂ© au moyen dâune analyse modifiĂ©e avant-aprĂšs/contrĂŽle-impact, les donnĂ©es historiques et les donnĂ©es de 2014 reprĂ©sentant les composantes avant-aprĂšs de lâanalyse, puis les jours avec et les jours sans activitĂ© dâarmes Ă air comprimĂ© reprĂ©sentant les composantes contrĂŽle-impact de lâanalyse. Les rĂ©sultats ont permis de constater dâimportants changements liĂ©s Ă lâemploi dâarmes Ă air comprimĂ© pour ce qui est des taux de prises Ă un ou plusieurs verveux, Ă p < 0,1 pour les huit espĂšces, et Ă p < 0,05 pour sept des huit espĂšces. Les changements se sont caractĂ©risĂ©s Ă la fois par des taux de prises plus Ă©levĂ©s et moins Ă©levĂ©s, ce qui reflĂ©tait peut-ĂȘtre le dĂ©placement des poissons en raison du son des armes Ă air comprimĂ© dans la zone visĂ©e par lâĂ©tude. Les niveaux de pression sonore mesurĂ©s en lien avec les impulsions dâarmes Ă air comprimĂ© Ă©taient faibles et habituellement indĂ©tectables Ă proximitĂ© des verveux, signe de la perte des ondes kilomĂ©triques dans lâeau peu profonde (~1,5 m). Les tentatives de mesure des vitesses acoustiques des particules ont Ă©chouĂ© lorsque les ondes de surface poussĂ©es par le vent submergeaient les capteurs de vecteur. Toutefois, la rĂ©action des poissons aurait pu ĂȘtre liĂ©e aux changements sur le plan du mouvement des particules dĂ©coulant du son des armes Ă air comprimĂ©
Immunohistochemical detection of scrapie prion proteins in clinically normal sheep in Pennsylvania
Following diagnosis of scrapie in a clinically suspect Suffolk sheep, 7 clinically normal flockmates were purchased by the Pennsylvania Department of Agriculture to determine their scrapie status using an immunohistochemical procedure. Two of the 7 euthanized healthy sheep had positive immunohistochemical staining of the prion protein of scrapie (PrP-Sc) in their brains, nictitating membranes, and tonsils. The PrP-Sc was localized in the areas of the brain where, histopathologically, there was neurodegeneration and astrocytosis. The PrP-Sc occurred within germinal centers of the affected nictitating membranes and tonsils and was located in the cytoplasm of the dendrite-like cells, lymphoid cells, and macrophages. These results confirm that immunohistochemical examination of the nictitating membrane can be used as a screen for the presence of scrapie infection in clinically normal sheep at a capable veterinary diagnostic laboratory. In sheep with a PrP-Scâpositive nictitating membrane, the diagnosis of scrapie should be confirmed by histopathology and immunohistochemical examination of the brain following necropsy. Following full validation, immunohistochemistry assays for detection of PrP-Sc in nictitating membrane lymphoid tissues can improve the effectiveness of the scrapie control and eradication program by allowing diagnosis of the disease in sheep before the appearance of clinical signs
Pathways to clinical CLARITY: volumetric analysis of irregular, soft, and heterogeneous tissues in development and disease
AbstractThree-dimensional tissue-structural relationships are not well captured by typical thin-section histology, posing challenges for the study of tissue physiology and pathology. Moreover, while recent progress has been made with intact methods for clearing, labeling, and imaging whole organs such as the mature brain, these approaches are generally unsuitable for soft, irregular, and heterogeneous tissues that account for the vast majority of clinical samples and biopsies. Here we develop a biphasic hydrogel methodology, which along with automated analysis, provides for high-throughput quantitative volumetric interrogation of spatially-irregular and friable tissue structures. We validate and apply this approach in the examination of a variety of developing and diseased tissues, with specific focus on the dynamics of normal and pathological pancreatic innervation and development, including in clinical samples. Quantitative advantages of the intact-tissue approach were demonstrated compared to conventional thin-section histology, pointing to broad applications in both research and clinical settings.</jats:p
A Multicenter Observer Performance Study of 3D JPEG2000 Compression of Thin-Slice CT
The goal of this study was to determine the compression level at which 3D JPEG2000 compression of thin-slice CTs of the chest and abdomenâpelvis becomes visually perceptible. A secondary goal was to determine if residents in training and non-physicians are substantially different from experienced radiologists in their perception of compression-related changes. This study used multidetector computed tomography 3D datasets with 0.625â1-mm thickness slices of standard chest, abdomen, or pelvis, clipped to 12Â bits. The Kakadu v5.2 JPEG2000 compression algorithm was used to compress and decompress the 80 examinations creating four sets of images: lossless, 1.5Â bpp (8:1), 1Â bpp (12:1), and 0.75Â bpp (16:1). Two randomly selected slices from each examination were shown to observers using a flicker mode paradigm in which observers rapidly toggled between two images, the original and a compressed version, with the task of deciding whether differences between them could be detected. Six staff radiologists, four residents, and six PhDs experienced in medical imaging (from three institutions) served as observers. Overall, 77.46% of observers detected differences at 8:1, 94.75% at 12:1, and 98.59% at 16:1 compression levels. Across all compression levels, the staff radiologists noted differences 64.70% of the time, the residentâs detected differences 71.91% of the time, and the PhDs detected differences 69.95% of the time. Even mild compression is perceptible with current technology. The ability to detect differences does not equate to diagnostic differences, although perception of compression artifacts could affect diagnostic decision making and diagnostic workflow
Lateral Connectivity in the Olfactory Bulb is Sparse and Segregated
Lateral connections in the olfactory bulb were previously thought to be organized for centerâsurround inhibition. However, recent anatomical and physiological studies showed sparse and distributed interactions of inhibitory granule cells (GCs) which tended to be organized in columnar clusters. Little is known about how these distributed clusters are interconnected. In this study, we use transsynaptic tracing viruses bearing green or red fluorescent proteins to further elucidate mitral- and tufted-to-GC connectivity. Separate sites in the glomerular layer were injected with each virus. Columns with labeling from both viruses after transsynaptic spread show sparse red or green GCs which tended to be segregated. However, there was a higher incidence of co-labeled cells than chance would predict. Similar segregation of labeling is observed from dual injections into olfactory cortex. Collectively, these results suggest that neighboring mitral and tufted cells receive inhibitory inputs from segregated subsets of GCs, enabling inhibition of a center by specific and discontinuous lateral elements
Polycyclic aromatic hydrocarbons (PAH) and polychlorinated biphenyls (PCB) in urban soils of Greater London, UK
Surface soils from a 19 km2 area in east London, UK were analysed for polycyclic aromatic hydrocarbons (PAH) and polychlorinated biphenyls (PCB) (n = 76). â16 PAH ranged from 4 to 67 mg/kg (mean, 18 mg/kg) and â50 PAH ranged from 6 to 88 mg/kg (mean, 25 mg/kg). â7 PCB ranged from 1 to 750 ÎŒg/kg (mean, 22 ÎŒg/kg) and âtri-hepta PCB ranged 9 to 2600 ÎŒg/kg (mean, 120 ÎŒg/kg). Compared to other international cities concentrations were similar for PAH but higher for PCB. Normal background concentrations (NBC) were calculated and compared to risk-based human health generic assessment criteria (GAC). Benzo[a]pyrene NBC for urban (6.9 mg/kg), semi-urban (4.4 mg/kg) and urban + semi urban (6 mg/kg) domains exceed residential (1 mg/kg) and allotment (2.2 mg/kg) LQM/CIEH GAC (at 6% SOM) and the Indeno[1,2,3-cd]pyrene NBC for urban (6.8 mg/kg) and urban + semi-urban (5.2 mg/kg) domains exceed the residential (4.2 mg/kg) LQM/CIEH GAC (at 6% SOM).
Capsule Abstract: Normal background concentrations of polycyclic aromatic hydrocarbons and polychlorinated biphenyls are elevated in east London soils and in some cases exceed regulatory assessment criteria
Nonmedical prescription drug use among US young adults by educational attainment
Purpose: Little is known about nonmedical use of prescription drugs among non-college-attending young adults in the United States. Methods: Data were drawn from 36,781 young adults (ages 18â22 years) from the 2008â2010 National Survey on Drug Use and Health public use files. The adjusted main effects for current educational attainment, along with its interaction with gender and race/ethnicity, were considered. Results: Compared to those attending college, non-college-attending young adults with at least and less than a HS degree had a higher prevalence of past-year nonmedical use of prescription opioids [NMUPO 13.1 and 13.2 %, respectively, vs. 11.3 %, adjusted odds ratios (aORs) 1.21 (1.11â1.33) and 1.25 (1.12â1.40)], yet lower prevalence of prescription stimulant use. Among users, regardless of drug type, non-college-attending youth were more likely to have past-year disorder secondary to use [e.g., NMUPO 17.4 and 19.1 %, respectively, vs. 11.7 %, aORs 1.55 (1.22â1.98) and 1.75 (1.35â2.28)]. Educational attainment interacted with gender and race: (1) among nonmedical users of prescription opioids, females who completed high school but were not enrolled in college had a significantly greater risk of opioid disorder (compared to female college students) than the same comparison for men; and (2) the risk for nonmedical use of prescription opioids was negligible across educational attainment groups for Hispanics, which was significantly different than the increased risk shown for non-Hispanic whites. Conclusions: There is a need for young adult prevention and intervention programs to target nonmedical prescription drug use beyond college campuses
Accommodating false positives within acoustic spatial captureârecapture, with variable source levels, noisy bearings and an inhomogeneous spatial density
Funding: Tiago Marques was partly supported by CEAUL (funded by FCT - Fundação para a CiĂȘncia e a Tecnologia, Portugal, through the project UIDB/00006/2020).Passive acoustic monitoring is a promising method for surveying wildlife populations that are easier to detect acoustically than visually. When animal vocalisations can be uniquely identified on an array of sensors, the potential exists to estimate population density through acoustic spatial captureârecapture (ASCR). However, sound classification is imperfect, and in some situations, a high proportion of sounds detected on just a single sensor (âsingletonsâ) are not from the target species. We present a case study of bowhead whale calls (Baleana mysticetus) collected in the Beaufort Sea in 2010 containing such false positives. We propose a novel extension of ASCR that is robust to false positives by truncating singletons and conditioning on calls being detected by at least two sensors. We allow for individual-level detection heterogeneity through modelling a variable sound source level, model inhomogeneous call spatial density, and include bearings with varying measurement error. We show via simulation that the method produces near-unbiased estimates when correctly specified. Ignoring source-level variation resulted in a strong negative bias, while ignoring inhomogeneous density resulted in severe positive bias. The case study analysis indicated a band of higher call density approximately 30 km from shore; 59.8% of singletons were estimated to have been false positives.Publisher PDFPeer reviewe
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