277 research outputs found
Assessing the threat of toxic contaminants to early marine survival of Chinook salmon in the Salish Sea
Human development of the Salish Sea has resulted in loss and modification of salmonid habitats, including reduced habitat quality due to contaminant inputs, particularly in the lower reaches of rivers and estuaries of the central Puget Sound. Chemical contaminants released into the Salish Sea from anthropogenic sources can reduce the health and productivity of salmon. Juvenile salmon are exposed to contaminants in freshwater, estuarine, and marine habitats but they are particularly vulnernable as they transition from fresh to saltwater because this life history stage is especially sensitive to stressors that may reduce their early marine survival. Reduced growth and disease resistance have been demonstrated for juvenile Chinook salmon exposed to environmentally relevant contaminant levels; however, synoptic, Puget Sound-wide surveys to assess the extent and magnitude of contaminant exposure are lacking. In this study we measured exposure of juvenile Chinook salmon to chemicals of concern that enter Puget Sound via stormwater, wastewater treatment facilities, atmospheric deposition to marine waters, and groundwater. During the spring and summer of 2013, outmigrating fish were sampled from the river mouthes and two adjacent marine shorelines at each of five Puget Sound river-estuary systems: Skagit, Snohomish, Green/Duwamish, Puyallup/Hylebos, and Nisqually. We (1) report the extent and magnitude of exposure, (2) compare exposure in outmigrants across five major river-estuary systems, and (3) evaluate potential effects on marine survival. Results will be used to establish a time series of contaminant conditions in juvenile Chinook salmon to measure the effectiveness of current toxics reductions strategies and actions, inform future pollution reduction efforts, and enhanced recovery of Chinook salmon
Spreading of rinsing liquids across a horizontal rotating substrate
‘‘Rinsing” liquids and their dynamics are interesting both fundamentally in the interaction of several classic modes of spreading, and industrially in a variety of cleaning applications, such as in the manufacturing of silicon wafers. In this paper, we investigate the time-dependent spreading behavior of a rinsing liquid across a horizontal, rotating substrate; the rinsing liquid is applied to the center of the rotating substrate as an orthogonal impinging jet of constant volumetric flow. We present experimental findings on the azimuthally averaged outer radius of the spreading liquid, in which we observed four distinct growth behaviors in time. We use lubrication theory to explain these phenomena and to define boundaries within the explored parameter space where each was observed. In the absence of rotation, capillarity dominates and the spreading radius grows as t^(4/10). When centrifugal forces dominate the spreading process, several time dependencies of the spreading radius are possible, with lubrication theory predicting exponential growth as well as power laws of t^(3/4) and t^(3/2)
3D morphometric analysis of calcified cartilage properties using micro-computed tomography
Objective: Our aim is to establish methods for quantifying morphometric properties of calcified cartilage (CC) from micro-computed tomography (mu CT). Furthermore, we evaluated the feasibility of these methods in investigating relationships between osteoarthritis (OA), tidemark surface morphology and open subchondral channels (OSCCs). Method: Samples (n = 15) used in this study were harvested from human lateral tibial plateau (n = 8). Conventional roughness and parameters assessing local 3-dimensional (3D) surface variations were used to quantify the surface morphology of the CC. Subchondral channel properties (percentage, density, size) were also calculated. As a reference, histological sections were evaluated using Histopathological osteoarthritis grading (OARSI) and thickness of CC and subchondral bone (SCB) was quantified. Results: OARSI grade correlated with a decrease in local 3D variations of the tidemark surface (amount of different surface patterns (r(s) = -0.600, P = 0.018), entropy of patterns (EP) (r(s) = -0.648, P = 0.018), homogeneity index (HI) (r(s) = 0.555, P = 0.032)) and tidemark roughness (TMR) (r(s) = -0.579, P = 0.024). Amount of different patterns (ADP) and EP associated with channel area fraction (CAF) (r(p) = 0.876, P <0.0001; r(p) = 0.665, P = 0.007, respectively) and channel density (CD) (r(p) = 0.680, P = 0.011; r(p) = 0.582, P = 0.023, respectively). TMR was associated with CAF (r(p) = 0.926, P <0.0001) and average channel size (r(p) = 0.574, P = 0.025). CC topography differed statistically significantly in early OA vs healthy samples. Conclusion: We introduced a mu-CT image method to quantify 3D CC topography and perforations through CC. CC topography was associated with OARSI grade and OSCC properties; this suggests that the established methods can detect topographical changes in tidemark and CC perforations associated with OA. (c) 2018 The Authors. Published by Elsevier Ltd on behalf of Osteoarthritis Research Society International. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Peer reviewe
Harbor seal pup dispersal and individual morphology, hematology, and contaminant factors affecting survival
This work was funded by The Valentine Family Foundation and the John H. Prescott Marine Mammal Rescue Assistance Grant Program.Understanding the factors affecting individual harbor seal (Phoca vitulina) survival is essential for determining population level health risks. We estimated postweaning dispersal, and modeled the effects of morphology, hematology, and blubber contaminants on the survival of recently weaned harbor seal pups using a mark recapture framework. We deployed satellite transmitters on apparently healthy pups captured in San Francisco Bay (SFB, n = 19) and Tomales Bay (TB, n = 7), and pups released after rehabilitation that stranded along the central California coast preweaning (n = 21). Dispersal distances were further than previously reported for harbor seal pups (maximum = 802 km) which has implications for understanding risks to this vulnerable age class. We found differences in body condition, serum immunoglobulin and thyroxine (T4) concentrations, white blood cell count, and blubber organohalogen contamination (OH) among the three groups. Overall, increased T4, decreased OH, and increased mass were associated with greater survival probabilities; whereas, among stranded seals, greater mass gain, shorter time in rehabilitation, and admission to rehabilitation earlier in the season were associated with greater survival probabilities. Attention to these latter factors may improve the success of rehabilitation efforts. For wild pups, reduction of legacy contaminants and direct causes of mortality, such as ship strike, may enhance pup survival.Publisher PDFPeer reviewe
Assessing Perceived Risk and STI Prevention Behavior: A National Population-Based Study with Special Reference to HPV
Aim: This thesis aims to provide a multidimensional assessment of infection risks and
to evaluate strategies for HPV prevention including vaccination with quadrivalent HPVvaccines,
dose-level vaccine effectiveness and condom use in high STI risk situations.
Methods: Multiple population-based registers and questionnaire responses provided data
for this thesis. Various multivariable and univariate regression models were fit.
Findings: Overall, quadrivalent HPV-vaccination was highly effective against genital
warts (GW) also referred to as condyloma, which is the first HPV disease endpoint
possible to measure. However, effectiveness was contingent upon young age-at-first
vaccination, with effectiveness declining steadily the older the age-at-first vaccination.
Among women above 20 years of age there was low to immeasurable effectiveness and
suggestive evidence vaccinations in this age group tended to reach women at high GW
risk. There were marked socioeconomic disparities in the opportunistic (on-demand with
co-pay) vaccination strategy evaluated, with women and girls who have parents with
the highest education level compared to the lowest having a 15 times greater likelihood
to be vaccinated (Study III). Once vaccination was initiated, however, high parental
education level was unrelated to vaccination completion. Maximum protection against
GW was found among girls vaccinated under the age of 17 who had received three doses
of the vaccine. No differences in effectiveness were found for girls who received twodoses
between ages 10-16 with that of those who received three-doses between ages 17-
19 (Study IV). GW affects more men than women in Sweden as of 2010 with 453 per
100 000 men and 365 per 100 000 women treated. A decline between 25-30% was seen
between 2006 and 2010 among women in the age groups with the highest vaccination
coverage. No decline was found amongst men and their GW incidence has steadily
increased between 2006 and 2010 (Study II). Reported condom use in high risk situations
was low among both men and women, with 41% of men and 34% of women reporting
always/almost always condom use with temporary partners. STI risk perception was also
low, with approximately 10% of sexually active respondents considering themselves at
large risk of contracting an STI. There was no association between men’s condom use and
their STI risk perception but there was an association for women (Study I).
Conclusions: Results suggest that males bear a substantial burden of HPV-related
condyloma where incidence has dropped among women. When planning HPVvaccination
among females, efforts should target girls under age 14 for maximum
effectiveness. Quadrivalent HPV-vaccination offers most protection against condyloma at
three doses. Gross social inequity was found with opportunistic HPV-vaccination. There
were large gender differences in factors associated with condom use in high risk situations
and STI risk perceptions
Recurrent Die-Offs of Adult Coho Salmon Returning to Spawn in Puget Sound Lowland Urban Streams
Several Seattle-area streams in Puget Sound were the focus of habitat restoration projects in the 1990s. Post-project effectiveness monitoring surveys revealed anomalous behaviors among adult coho salmon returning to spawn in restored reaches. These included erratic surface swimming, gaping, fin splaying, and loss of orientation and equilibrium. Affected fish died within hours, and female carcasses generally showed high rates (>90%) of egg retention. Beginning in the fall of 2002, systematic spawner surveys were conducted to 1) assess the severity of the adult die-offs, 2) compare spawner mortality in urban vs. non-urban streams, and 3) identify water quality and spawner condition factors that might be associated with the recurrent fish kills. The forensic investigation focused on conventional water quality parameters (e.g., dissolved oxygen, temperature, ammonia), fish condition, pathogen exposure and disease status, and exposures to metals, polycyclic aromatic hydrocarbons, and current use pesticides. Daily surveys of a representative urban stream (Longfellow Creek) from 2002–2009 revealed premature spawner mortality rates that ranged from 60–100% of each fall run. The comparable rate in a non-urban stream was <1% (Fortson Creek, surveyed in 2002). Conventional water quality, pesticide exposure, disease, and spawner condition showed no relationship to the syndrome. Coho salmon did show evidence of exposure to metals and petroleum hydrocarbons, both of which commonly originate from motor vehicles in urban landscapes. The weight of evidence suggests that freshwater-transitional coho are particularly vulnerable to an as-yet unidentified toxic contaminant (or contaminant mixture) in urban runoff. Stormwater may therefore place important constraints on efforts to conserve and recover coho populations in urban and urbanizing watersheds throughout the western United States
Preparation and Characterization of a Lovastatin-Loaded Protein-Free Nanostructured Lipid Carrier Resembling High-Density Lipoprotein and Evaluation of its Targeting to Foam Cells
This study was designed to investigate whether a non-protein nanostructured lipid carrier (NLC) resembling high-density lipoprotein (HDL) could deliver a hydrophobic anti-atherogenic drug, lovastatin, to foam cells. Lovastatin-loaded NLC (LT-NLC) was prepared by a nanoprecipitation/solvent diffusion method. The LT-NLC-apoprotein (LT-NLC-apo) was prepared by incubating LT-NLC with native HDL. The physicochemical parameters of LT-NLC were characterized in terms of particle size, zeta potential, morphology, entrapment efficiency, and crystallization behavior. Targeting behavior and mechanism were demonstrated by the incubation of LT-NLC-apo with a RAW 264.7 macrophage-derived foam cell model in the presence or absence of very-low-density lipoprotein (VLDL) and lipase. The results showed that LT-NLC was solid spherical or oval in shape with an average diameter of 13.8 ± 2.2 nm, zeta potential of −29.3 ± 0.2 mV and entrapment efficiency of 96.2 ± 1.3%. Phagocytosis studies showed that uptake of LT-NLC-apo by macrophages was significantly lower than LT-NLC (p < 0.01), suggesting that LT-NLC-apo could possibly escape recognition from macrophages in vivo. The uptake was increased twofold when LT-NLC-apo was incubated with transfected foam cells containing VLDL and lipase. These results indicated that non-protein NLC resembling HDL could be a useful tool to deliver lipophilic anti-atherogenic drugs to foam cells, and that uptake could be enhanced by the VLDL receptor pathway
A Systems Genetics Approach Implicates USF1, FADS3, and Other Causal Candidate Genes for Familial Combined Hyperlipidemia
We hypothesized that a common SNP in the 3' untranslated region of the upstream transcription factor 1 (USF1), rs3737787, may affect lipid traits by influencing gene expression levels, and we investigated this possibility utilizing the Mexican population, which has a high predisposition to dyslipidemia. We first associated rs3737787 genotypes in Mexican Familial Combined Hyperlipidemia (FCHL) case/control fat biopsies, with global expression patterns. To identify sets of co-expressed genes co-regulated by similar factors such as transcription factors, genetic variants, or environmental effects, we utilized weighted gene co-expression network analysis (WGCNA). Through WGCNA in the Mexican FCHL fat biopsies we identified two significant Triglyceride (TG)-associated co-expression modules. One of these modules was also associated with FCHL, the other FCHL component traits, and rs3737787 genotypes. This USF1-regulated FCHL-associated (URFA) module was enriched for genes involved in lipid metabolic processes. Using systems genetics procedures we identified 18 causal candidate genes in the URFA module. The FCHL causal candidate gene fatty acid desaturase 3 (FADS3) was associated with TGs in a recent Caucasian genome-wide significant association study and we replicated this association in Mexican FCHL families. Based on a USF1-regulated FCHL-associated co-expression module and SNP rs3737787, we identify a set of causal candidate genes for FCHL-related traits. We then provide evidence from two independent datasets supporting FADS3 as a causal gene for FCHL and elevated TGs in Mexicans
Fear of falling in obese women under 50 years of age: a cross-sectional study with exploration of the relationship with physical activity
An understanding of capacity for physical activity in obese populations should help guide interventions to promote physical activity. Fear of falling is a phenomenon reported in the elderly, which is associated with reduced mobility and lower physical activity levels. However, although falls are reportedly common in obese adults, fear of falling and its relationship with activity has not been investigated in younger obese populations. In a cross-sectional study, fear of falling was measured in 63 women aged 18 to 49 years, with mean BMI 42.1 kg/m (SD 10.3) using the Modified Falls Efficacy (MFES), the Consequences of Falling (COF) and the Modified Survey of Activities and Fear of Falling in the Elderly (MSAFFE) scales. The choice of scales was informed by prior qualitative interviews with obese younger women. Physical activity levels were measured at the same time using the International Physical Activity Questionnaire. The mean score for fear of falling scales, with 95% confidence intervals, were estimated. Chi-square tests and t-tests were used to explore differences in age, body mass index and fear of falling scores between fallers and non-fallers. For each fear of falling scale, binomial logistic regression was used to explore its relationship with physical activity. Mean scores suggested high levels of fear of falling: MFES [mean 7.7 (SD 2.7); median 8.5]; COF [mean 31.3 (SD 9.4)]; MSAFFE [mean 25.9 (SD 8.7); median 23]. Scores were significantly worse in fallers ( = 42) compared to non-fallers ( = 21). MFES and MSAFFE were independently associated with lower levels of physical activity [odds ratio = 0.65, 95% Cl 0.44 to 0.96 and odds ratio = 1.14, 95% CI 1.01 to 1.28 respectively], when adjusted for age, BMI and depression. This study confirms that fear of falling is present in obese women under 50 years of age. It suggests that it is associated with low levels of physical activity. These novel findings warrant further research to understand capacity for physical and incidental activity in obese adults in both genders and suggest innovative interventions to promote lifestyle changes and/or consideration of falls prevention in this population
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