7,058 research outputs found

    Synergistic Effects of Temperature and Salinity on the Gene Expression and Physiology of Crassostrea virginica

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    © 2019 The Author(s). The eastern oyster, Crassostrea virginica, forms reefs that provide critical services to the surrounding ecosystem. These reefs are at risk from climate change, in part because altered rainfall patterns may amplify local fluctuations in salinity, impacting oyster recruitment, survival, and growth. As in other marine organisms, warming water temperatures might interact with these changes in salinity to synergistically influence oyster physiology. In this study, we used comparative transcriptomics, measurements of physiology, and a field assessment to investigate what phenotypic changes C. virginica uses to cope with combined temperature and salinity stress in the Gulf of Mexico. Oysters from a historically low salinity site (Sister Lake, LA) were exposed to fully crossed temperature (20°C and 30°C) and salinity (25, 15, and 7 PSU) treatments. Using comparative transcriptomics on oyster gill tissue, we identified a greater number of genes that were differentially expressed (DE) in response to low salinity at warmer temperatures. Functional enrichment analysis showed low overlap between genes DE in response to thermal stress compared with hypoosmotic stress and identified enrichment for gene ontologies associated with cell adhesion, transmembrane transport, and microtubule-based process. Experiments also showed that oysters changed their physiology at elevated temperatures and lowered salinity, with significantly increased respiration rates between 20°C and 30°C. However, despite the higher energetic demands, oysters did not increase their feeding rate. To investigate transcriptional differences between populations in situ, we collected gill tissue from three locations and two time points across the Louisiana Gulf coast and used quantitative PCR to measure the expression levels of seven target genes. We found an upregulation of genes that function in osmolyte transport, oxidative stress mediation, apoptosis, and protein synthesis at our low salinity site and sampling time point. In summary, oysters altered their phenotype more in response to low salinity at higher temperatures as evidenced by a higher number of DE genes during laboratory exposure, increased respiration (higher energetic demands), and in situ differential expression by season and location. These synergistic effects of hypoosmotic stress and increased temperature suggest that climate change will exacerbate the negative effects of low salinity exposure on eastern oysters

    Unpackaging demand for water service quality : evidence from conjoint surveys in Sri Lanka

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    In the early 2000s, the Government of Sri Lanka considered engaging private sector operators to manage water and sewerage services in two separate service areas: one in the town of Negombo (north of Colombo), and one stretching along the coastal strip (south from Colombo) from the towns of Kalutara to Galle. Since then, the government has abandoned the idea of setting up a public-private partnership in these two areas. This paper is part of a series of investigations to determine how these pilot private sector transactions (forming part of the overall water sector reform strategy) could be designed in such a manner that they would benefit the poor. The authors describe the results of a conjoint survey evaluating the factors that drive customer demand for alternative water supply and sanitation services in Sri Lanka. They show how conjoint surveys can be used to unpackage household demand for attributes of urban services and improve the design of infrastructure policies. They present conjoint surveys as a tool for field experiments and a source of valuable empirical data. In the study of three coastal towns in southwestern Sri Lanka the conjoint survey allows the authors to compare household preferences for four water supply attributes-price, quantity, safety, and reliability. They examine subpopulations of different income levels to determine if demand is heterogeneous. The case study suggests that households care about service quality (not just price). In general, the authors find that households have diverse preferences in terms of quantity, safety, and service options, but not with regard to hours of supply. In particular, they find that the poor have lower ability to trade off income for services, a finding that has significant equity implications in terms of allocating scarce public services and achieving universal water access.Town Water Supply and Sanitation,Water and Industry,Economic Theory&Research,Water Use,Water Supply and Sanitation Governance and Institutions

    TGF beta 1 attenuates expression of prolactin and IGFBP-1 in decidualized endometrial stromal cells by both SMAD-dependent and SMAD-independent pathways

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    Background: Decidualization (differentiation) of the endometrial stromal cells during the secretory phase of the menstrual cycle is essential for successful implantation. Transforming Growth Factor beta 1 (TGF beta 1) canonically propagates its actions via SMAD signalling. A role for TGF beta 1 in decidualization remains to be established and published data concerning effects of TGF beta 1 on markers of endometrial decidualization are inconsistent. Methodology/Principal Findings: Non-pregnant endometrial stromal cells (ESC) and first trimester decidual stromal cells (DSC) were cultured in the presence or absence of a decidualizing stimulus. Incubation of ESCs with TGF beta 1 (10 ng/ml) down-regulated the expression of transcripts encoding the decidual marker proteins prolactin (PRL), insulin-like growth factor binding protein-1 (IGFBP-1) and tissue factor (TF). TGF beta 1 also inhibited secretion of PRL and IGFBP-1 proteins by ESCs and surprisingly this response preceded down-regulation of their mRNAs. In contrast, DSCs were more refractory to the actions of TGF beta 1, characterized by blunted and delayed down-regulation of PRL, IGFBP-1, and TF transcripts, which was not associated with a significant reduction in secretion of PRL or IGFBP-1 proteins. Addition of an antibody directed against TGF beta 1 increased expression of IGFBP-1 mRNA in decidualised cells. Knockdown of SMAD 4 using siRNAs abrogated the effect of TGF beta 1 on expression of PRL in ESCs but did not fully restore expression of IGFBP-1 mRNA and protein. Conclusions/Significance: TGF beta 1 inhibits the expression and secretion of decidual marker proteins. The impact of TGF beta 1 on PRL is SMAD-dependent but the impact on IGFBP1 is via an alternative mechanism. In early pregnancy, resistance of DSC to the impact of TGF beta 1 may be important to ensure tissue homeostasis

    How do I sound to me? Perceived changes in communication in Parkinson's disease

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    Objective: To examine self and carer perceived changes in communication associated with Parkinson's disease and relate these to speech intelligibility, gender, age and other disease measures. Design: Cross-sectional survey of a hospital- and community-based sample of 176 people with Parkinson's disease and their carers using a questionnaire based on semantic differential techniques. Participants: One hundred and four people with Parkinson's disease with no history of communication difficulties prior to onset of their Parkinson's disease and 45 primary carers who returned completed questionnaires. Main outcome measures: Differences in ratings for `before' the onset of Parkinson's disease versus present status. Results: There was a strong perception of negative impact on communication between `before' and `now', irrespective of age and gender and largely independent of disease severity and duration, intelligibility and cognitive status. Activities of daily living (assessed by Unified Parkinson's Disease Rating Scale (UPDRS) II) and depression rating scale scores had the strongest association with change (adjusted R 2 0.27). There was a significant correlation between the rank order of perceived change in features examined in people with Parkinson's disease versus their carers, though in general carers rated change as having less impact. Conclusions: Parkinson's disease exercises a strong influence on communication even before apparent alterations to intelligibility or motor status

    Extinction and backscatter measurements of Antarctic PSC's, 1987: Implications for particle and vapor removal

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    The temperature dependence is examined of optical properties measured in the Antarctic during 1987 at the 70 mb level (near 18 km), a level chosen to correlate the results with in situ measurements made from the NASA-Ames ER-2 aircraft during the 1987 Airborne Antarctic Ozone Experiment (AAOE). The data set consists of extinction measurements by Sam 2 inside the Antarctic polar vortex from May to October 1987; and backscatter measurements by the UV-DIAL (Ultraviolet Differential Absorption Lidar) system aboard the Ames DC-8 aircraft during selected AAOE flights. Observed trends are compared with results from a revised version of Pole and McCormick's model to classify the PSC observations by Type (1 or 2) and infer the temporal behavior of the ambient aerosol and ambient vapor mixing ratios. The sample figures show monthly ensembles of the 70-mb Sam 2 extinction ratio (the ratio of aerosol or PSC extinction to molecule extinction) as a function of NMC temperature at the beginning (June) and (October) of the 1987 Antarctic winter. Both ensembles show two rather distinct clusters of points: one oriented in the near vertical direction which depicts the change with temperature of the ambient aerosol extinction ratio; and a second cluster oriented in the near horizontal direction whose position on the vertical scale marks a change in particle phase (i.e., PSC formation) and whose length (the extinction enhancement related to that of the ambient aerosol) is an indicator of PSC type

    The role of adjuvant in mediating antigen structure and stability

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    The purpose of this study was to probe the fate of a model antigen, a cysteine-free mutant of bacteriophage T4 lysozyme, to the level of fine structural detail, as a consequence of its interaction with an aluminum (Al)-containing adjuvant. Fluorescence spectroscopy and differential scanning calorimetry were used to compare the thermal stability of the protein in solution versus adsorbed onto an Al-containing adjuvant. Differences in accessible hydrophobic surface areas were investigated using an extrinsic fluorescence probe, 8-Anilino-1-naphthalenesulfonic acid (ANS). As has been observed with other model antigens, the apparent thermal stability of the protein decreased following adsorption onto the adjuvant. ANS spectra suggested that adsorption onto the adjuvant caused an increase in exposure of hydrophobic regions of the protein. Electrostatic interactions drove the adsorption, and disruption of these interactions with high ionic strength buffers facilitated the collection of two-dimensional 15N heteronuclear single quantum coherence nuclear magnetic resonance data of protein released from the adjuvant. Although the altered stability of the adsorbed protein suggested changes to the protein\u27s structure, the fine structure of the desorbed protein was nearly identical to the protein\u27s structure in the adjuvant-free formulation. Thus, the adjuvant-induced changes to the protein that were responsible for the reduced thermal stability were not observed upon desorption. © 2011 Wiley Periodicals, Inc

    Investigating the widely held belief that men and women with learning disabilities receive poor quality healthcare when admitted to hospital: a single-site study of 30-day readmission rates.

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    BACKGROUND: This study aims to use 30-day readmission rates to investigate the presumption that men and women with learning disabilities (LDs, known internationally as intellectual disabilities) receive poorer quality hospital care than their non-disabled peers. METHOD: A 12-month retrospective audit was conducted using Hospital Episode Statistics (HES) at a single acute hospital in the East of England. This identified all in-patient admissions; admissions where the person concerned was recognised as having a LD; and all emergency readmissions within 30 days of discharge. Additionally, the healthcare records of all patients identified as having a LD and readmitted within 30 days as a medical emergency were examined in order to determine whether or not these readmissions were potentially preventable. RESULTS: Over the study period, a total of 66 870 adults were admitted as in-patients, among whom 7408 were readmitted as medical emergencies within 30 days of discharge: a readmission rate of 11%. Of these 66 870 patients, 256 were identified as having a LD, with 32 of them experiencing at least one emergency readmission within 30 days: a readmission rate of 13%. When examined, the healthcare records pertaining to these 32 patients who had a total of 39 unique 30-day readmissions revealed that 69% (n = 26) of these readmissions were potentially preventable. CONCLUSION: Although overall readmission rates were similar for patients with LDs and those from the general population, patients with LDs had a much higher rate of potentially preventable readmissions when compared to a general population estimate from van Walraven et al. This suggests that there is still work to be done to ensure that this patient population receives hospital care that is both safe and of high quality.This research was funded by a grant from the Addenbrooke's Charitable Trust (CK), while the preparation of this paper was funded by the Health Foundation (AH, MR) and the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care East of England (AH, MR, AW) at Cambridgeshire and Peterborough NHS Foundation Trust.This is the author accepted manuscript. The final version is available from Wiley via http://dx.doi.org/10.1111/jir.1219

    Personal exposure to air pollution and respiratory health of COPD patients in London

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    Previous studies have investigated the effects of air pollution on chronic obstructive pulmonary disease (COPD) patients using either fixed site measurements or a limited number of personal measurements, usually for one pollutant and a short time period. These limitations may introduce bias and distort the epidemiological associations as they do not account for all the potential sources or the temporal variability of pollution.We used detailed information on individuals' exposure to various pollutants measured at fine spatio-temporal scale to obtain more reliable effect estimates. A panel of 115 patients was followed up for an average continuous period of 128 days carrying a personal monitor specifically designed for this project that measured temperature, PM10, PM2.5, NO2, NO, CO and O3 at one-minute time resolution. Each patient recorded daily information on respiratory symptoms and measured peak expiratory flow (PEF). A pulmonologist combined related data to define a binary variable denoting an "exacerbation". The exposure-response associations were assessed with mixed-effects models.We found that gaseous pollutants were associated with a deterioration in patients' health. We observed an increase of 16.4% (95% confidence interval: 8.6-24.6%), 9.4% (5.4-13.6%) and 7.6% (3.0-12.4%) in the odds of exacerbation for an interquartile range increase in NO2, NO and CO respectively. Similar results were obtained for cough and sputum. O3 was found to have adverse associations with PEF and breathlessness. No association was observed between particles and any outcome.Our findings suggest that, when considering total personal exposure to air pollutants, mainly the gaseous pollutants affect COPD patients' health

    Correlates of Continued Alcohol Consumption During Pregnancy: Implications for Health Promotion

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    Purpose: Too many women continue to drink alcohol during recognized pregnancy. This purpose of this study was to explore factors related to alcohol use during pregnancy. Design: Data came from reviews of charts from women that called the California Teratogen Information Service (CTIS) at some point during the time period from 1981 and 2006 and enrolled in a pregnancy outcome study. Subjects: Approximately 40% of the 181 women in the study sample were 25 years of age and younger, and most women had not previously given birth (61.3%). Measures: Chart extraction data included whether or not women discontinued alcohol consumption at anytime during pregnancy, at what point in their pregnancy they first contacted CTIS, and other demographic information. Results: Approximately 20% of women continued to drink alcohol throughout pregnancy and 37.6% contacted CTIS after the first trimester. Initiating contact with CTIS after the first trimester (p < .01) and being older than 25 years of age (p < .05) were both associated with continued drinking throughout pregnancy. Conclusion: Older women, still of reproductive age, may benefit most from health promotion interventions that focus on alcohol consumption during pregnancy

    Feral swine \u3ci\u3eSus scrofa\u3c/i\u3e: a new threat to the remaining breeding wetlands of the Vulnerable reticulated flatwoods salamander \u3ci\u3eAmbystoma bishopi\u3c/i\u3e

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    Feral swine Sus scrofa have been implicated as a major threat to sensitive habitats and ecosystems as well as threatened wildlife. Nevertheless, direct and indirect impacts on threatened species (especially small, fossorial species) are not well documented. The decline of the U.S. federally endangered reticulated flatwoods salamander Ambystoma bishopi, categorized as Vulnerable on the IUCN Red List, has been rapid and there are few remaining breeding locations for this species. The flatwoods salamander depends on complex herbaceous vegetation in all life stages, including eggs, larvae and adults. Historically sets of hog tracks have been observed only occasionally in the vicinity of monitored reticulated flatwoods salamander breeding wetlands, and damage to the wetlands had never been recorded. However, during the autumn–winter breeding season of 2013-2014 we observed a large increase in hog sign, including extensive rooting damage, in known flatwoods salamander breeding wetlands. Our objective was to assess the amount of hog sign and damage in these wetlands and to take corrective management actions to curb additional impacts. Of 28 wetlands surveyed for hog sign, presence was recorded at 68%, and damage at 54%. Of the 11 sites known to be occupied by flatwoods salamanders in 2013-2014, 64% had presence, and 55% had damage. We found that regular monitoring of disturbance in wetland habitats was a valuable tool to determine when intervention was needed and to assess the effectiveness of intervention. Habitat damage caused by feral hogs poses a potentially serious threat to the salamanders, which needs to be mitigated using methods to control and exclude hogs from this sensitive habitat
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