243 research outputs found

    Interactions between Zooplankton and Crude Oil: Toxic Effects and Bioaccumulation of Polycyclic Aromatic Hydrocarbons

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    We conducted ship-, shore- and laboratory-based crude oil exposure experiments to investigate (1) the effects of crude oil (Louisiana light sweet oil) on survival and bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) in mesozooplankton communities, (2) the lethal effects of dispersant (Corexit 9500A) and dispersant-treated oil on mesozooplankton, (3) the influence of UVB radiation/sunlight exposure on the toxicity of dispersed crude oil to mesozooplankton, and (4) the role of marine protozoans on the sublethal effects of crude oil and in the bioaccumulation of PAHs in the copepod Acartia tonsa. Mortality of mesozooplankton increased with increasing oil concentration following a sigmoid model with a median lethal concentration of 32.4 ml L21 in 16 h. At the ratio of dispersant to oil commonly used in the treatment of oil spills (i.e. 1:20), dispersant (0.25 ml L21 ) and dispersant- treated oil were 2.3 and 3.4 times more toxic, respectively, than crude oil alone (5 ml L21 ) to mesozooplankton. UVB radiation increased the lethal effects of dispersed crude oil in mesozooplankton communities by 35%. We observed selective bioaccumulation of five PAHs, fluoranthene, phenanthrene, pyrene, chrysene and benzo[b]fluoranthene in both mesozooplankton communities and in the copepod A. tonsa. The presence of the protozoan Oxyrrhis marina reduced sublethal effects of oil on A. tonsa and was related to lower accumulations of PAHs in tissues and fecal pellets, suggesting that protozoa may be important in mitigating the harmful effects of crude oil exposure in copepods and the transfer of PAHs to higher trophic levels. Overall, our results indicate that the negative impact of oil spills on mesozooplankton may be increased by the use of chemical dispersant and UV radiation, but attenuated by crude oil-microbial food webs interactions, and that both mesozooplankton and protozoans may play an important role in fate of PAHs in marine environments.Zoe Wambaugh was supported by the National Science Foundation (NSF) Research Experiences for Undergraduates (REU) program (grant OCE- 1062745). This research was made possible by a grant from BP/The Gulf of Mexico Research Initiative through the University of Texas Marine Science Institute (DROPPS consortium: ‘Dispersion Research on Oil: Physics and Plankton Studies’). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Marine Scienc

    How much crude oil can zooplankton ingest? Estimating the quantity of dispersed crude oil defecated by planktonic copepods

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    AbstractWe investigated and quantified defecation rates of crude oil by 3 species of marine planktonic copepods (Temora turbinata, Acartia tonsa, and Parvocalanus crassirostris) and a natural copepod assemblage after exposure to mechanically or chemically dispersed crude oil. Between 88 and 100% of the analyzed fecal pellets from three species of copepods and a natural copepod assemblage exposed for 48 h to physically or chemically dispersed light crude oil contained crude oil droplets. Crude oil droplets inside fecal pellets were smaller (median diameter: 2.4–3.5 μm) than droplets in the physically and chemically dispersed oil emulsions (median diameter: 6.6 and 8.0 μm, respectively). This suggests that copepods can reject large crude oil droplets or that crude oil droplets are broken into smaller oil droplets before or during ingestion. Depending on the species and experimental treatments, crude oil defecation rates ranged from 5.3 to 245 ng-oil copepod−1 d−1, which represent a mean weight-specific defecation rate of 0.026 μg-oil μg-Ccopepod1 d−1. Considering a dispersed crude oil concentration commonly found in the water column after oil spills (1 μl L−1) and copepod abundances in high productive coastal areas, copepods may defecate ∼1.3–2.6 mg-oil m−3 d−1, which would represent ∼0.15%–0.30% of the total dispersed oil per day. Our results indicate that ingestion and subsequent defecation of crude oil by planktonic copepods has a small influence on the overall mass of oil spills in the short term, but may be quantitatively important in the flux of oil from surface water to sediments and in the transfer of low-solubility, toxic petroleum hydrocarbons into food webs after crude oil spills in the sea

    Influence of UVB radiation on the lethal and sublethal toxicity of dispersed crude oil to planktonic copepod nauplii

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    AbstractToxic effects of petroleum to marine zooplankton have been generally investigated using dissolved petroleum hydrocarbons and in the absence of sunlight. In this study, we determined the influence of natural ultraviolet B (UVB) radiation on the lethal and sublethal toxicity of dispersed crude oil to naupliar stages of the planktonic copepods Acartia tonsa, Temora turbinata and Pseudodiaptomus pelagicus. Low concentrations of dispersed crude oil (1 μL L−1) caused a significant reduction in survival, growth and swimming activity of copepod nauplii after 48 h of exposure. UVB radiation increased toxicity of dispersed crude oil by 1.3–3.8 times, depending on the experiment and measured variables. Ingestion of crude oil droplets may increase photoenhanced toxicity of crude oil to copepod nauplii by enhancing photosensitization. Photoenhanced sublethal toxicity was significantly higher when T. turbinata nauplii were exposed to dispersant-treated oil than crude oil alone, suggesting that chemical dispersion of crude oil may promote photoenhanced toxicity to marine zooplankton. Our results demonstrate that acute exposure to concentrations of dispersed crude oil and dispersant (Corexit 9500) commonly found in the sea after oil spills are highly toxic to copepod nauplii and that natural levels of UVB radiation substantially increase the toxicity of crude oil to these planktonic organisms. Overall, this study emphasizes the importance of considering sunlight in petroleum toxicological studies and models to better estimate the impact of crude oil spills on marine zooplankton

    A Retrospective Analysis of Opioid Consumption Among Different Orthopedic Surgeons for Total Joint Replacement

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    Background: Throughout the world, baby boomers reaching their sixth, seventh, and eighth decade of life are requiring a significant number of joint replacements—hips and knees. Due to the increasing number of joint replacements, it is important to find a multi-modal approach (MMA) to control pain, reduce the amount of opioid consumption, and improve patient satisfaction. Purpose: The purpose of this study was to evaluate the intraoperative, postoperative, and total opioid consumption of patients undergoing total hip and knee replacements in an effort to develop a multi-modal approach to decrease opioid consumption, minimize adverse effects secondary to narcotic administration, and to achieve better pain control. This MMA was achieved by administering oxycodone, gabapentin, celecoxib, and acetaminophen starting before surgical incision. Methods: The study sample consisted of 192 patients undergoing total hip and knee replacements over a 10-month period between June 2012 and March 2013 at UMASS Memorial performed by five orthopedic surgeons. The main objective was to record intraoperative, postoperative, total opioid consumption, and patient satisfaction amongst these patients. Furthermore, the patients were subdivided based on the type of procedure (hip vs knee), type of anesthetic (general vs spinal), and the presence or absence of an indwelling catheter to deliver anesthetic (catheter vs no catheter). Results: The data showed a large variability among the surgeons in regards to the amount of opioid used intraoperatively, postoperatively and total opioid consumption. In terms of type of anesthetic, the patients undergoing spinal anesthesia used statistically significantly less opioids intraoperatively but not postoperatively, compared to general anesthesia. As for catheter use with general and spinal anesthesia, surprisingly, there was no significant difference in opioid consumption compared to the non-catheter counterpart. Furthermore, there seems to be no correlation between body mass index (BMI) and intraoperative or postoperative opioid use. Patient satisfaction was another variable that showed no correlation with opioid use intraoperatively or postoperatively. In terms of age, the data suggests that older patients use less opioids postoperatively in both hip and knee replacements. Conclusions: Our results quantitatively show spinal anesthesia to be far superior than general anesthesia in both joint replacements. Spinal anesthesia provides better pain control intraoperatively which allows one to use less opioids, thereby minimizing the adverse side effects of narcotic administration which include respiratory depression, urinary retention, nausea and post-operative ileus to name just a few. One surgeon’s patients required significantly less opioids intraoperatively compared to the rest of the surgeons. Further studies might warrant examining this surgeon’s technique or the demographics of his patient population to determine how better pain control and less opioid consumption could be achieved across all joints with all participating surgeons

    Novel insight into the role of heterotrophic dinoflagellates in the fate of crude oil in the sea

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    Although planktonic protozoans are likely to interact with dispersed crude oil after a spill, protozoan-mediated processes affecting crude oil pollution in the sea are still not well known. Here, we present the first evidence of ingestion and defecation of physically or chemically dispersed crude oil droplets (1–86 μm in diameter) by heterotrophic dinoflagellates, major components of marine planktonic food webs. At a crude oil concentration commonly found after an oil spill (1 μL L(−1)), the heterotrophic dinoflagellates Noctiluca scintillans and Gyrodinium spirale grew and ingested ~0.37 μg-oil μg-C(dino)(−1) d(−1), which could represent ~17% to 100% of dispersed oil in surface waters when heterotrophic dinoflagellates are abundant or bloom. Egestion of faecal pellets containing crude oil by heterotrophic dinoflagellates could contribute to the sinking and flux of toxic petroleum hydrocarbons in coastal waters. Our study indicates that crude oil ingestion by heterotrophic dinoflagellates is a noteworthy route by which petroleum enters marine food webs and a previously overlooked biological process influencing the fate of crude oil in the sea after spills

    Impact of IPDE-SQ personality disorders on the healthcare and societal costs of fibromyalgia patients: A cross-sectional study

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    Background: Data is lacking on comorbid personality disorders (PD) and fibromyalgia syndrome (FMS) in terms of prevalence, and associated healthcare and societal costs. The main aim of this study was to assess the prevalence of PD in FMS patients and to analyse whether the presence of comorbid PD is related to worse functional impairment and greater healthcare (medical visits, drug consumption, and medical tests) and societal costs. Methods: A cross-sectional study was performed using the baseline data of 216 FMS patients participating in a randomized, controlled trial carried out in three primary health care centres situated in the region of Barcelona, Spain. Measurement instruments included the International Personality Disorder Examination - Screening Questionnaire (IPDE-SQ), the Fibromyalgia Impact Questionnaire (FIQ), the Client Service Receipt Inventory (CSRI), and a socio-demographic questionnaire. Results: Most patients (65 %) had a potential PD according to the IPDE-SQ. The most prevalent PD were the avoidant (41.4 %), obsessive-compulsive (33.1 %), and borderline (27 %). We found statistically significant differences in functional impairment (FIQ scores) between FMS patients with potential PD vs non-PD (59.2 vs 51.1; p < 0.001). Multivariate regression analyses revealed that higher FIQ total scores and the presence of potential PD were related to more healthcare costs (primary and specialised care visits). Conclusions: As expected, PD are frequent comorbid conditions in patients with FMS. Our results suggest that the screening of comorbid PD in patients with FMS might be recommendable in order to detect potential frequent attenders to primary and specialised care

    Evaluation of a combined strategy directed towards health-care professionals and patients with chronic obstructive pulmonary disease (COPD): Information and health education feedback for improving clinical monitoring and quality-of-life

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    <p>Abstract</p> <p>Background</p> <p>Chronic obstructive pulmonary disease (COPD) is a health problem that is becoming increasingly attended-to in Primary Care (PC). However, there is a scarcity of health-care programs and studies exploring the implementation of Clinical Practice Guidelines (CPG). The principal objective of the present study is to evaluate the effectiveness of a combined strategy directed towards health-care professionals and patients to improve the grade of clinical control and the quality-of-life (QoL) of the patients via a feedback on their state-of-health. A training plan for the health-care professionals is based on CPG and health education.</p> <p>Method/Design</p> <p>Multi-centred, before-after, quasi experimental, prospective study involving an intervention group and a control group of individuals followed-up for 12 months. The patients receive attention from urban and semi-urban Primary Care Centres (PCC) within the administrative area of the Costa de Ponent (near Barcelona). All the pacients corresponding to the PCC of one sub-area were assigned to the intervention group and patients from the rest of sub-areas to the group control. The intervention includes providing data to the health-care professionals (clinician/nurse) derived from a clinical history and an interview. A course of training focused on aspects of CPG, motivational interview and health education (tobacco, inhalers, diet, physical exercise, physiotherapy). The sample random includes a total of 801 patients (≥ 40 years of age), recorded as having COPD, receiving attention in the PCC or at home, who have had at least one clinical visit, and who provided written informed consent to participation in the study. Data collected include socio-demographic characteristics, drug treatment, exacerbations and hospital admissions, evaluation of inhaler use, tobacco consumption and life-style and health-care resources consumed. The main endpoints are dyspnoea, according to the modified scale of the Medical Research Council (MRC) and the QoL, evaluated with the St George's Respiratory Questionnaire (SGRQ). The variables are obtained at the start and the end of the intervention. Information from follow-up visits focuses on the changes in life-style activities of the patient.</p> <p>Discussion</p> <p>This study is conducted with the objective of generating evidence that shows that implementation of awareness programs directed towards health-care professionals as well as patients in the context of PC can produce an increase in the QoL and a decrease in the disease exacerbation, compared to standard clinical practice.</p> <p>Trial Registration</p> <p>Clinical Trials.gov Identifier: NCT00922545;</p

    Evaluating the controlled reopening of nightlife during the COVID-19 pandemic : a matched cohort study in Sitges, Spain, in May 2021 (Reobrim Sitges)

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    To assess the impact of relaxing the state of alarm restrictions on SARS-CoV-2 infections at 14 days among people attending reopened nightclub venues. Matched cohort study with a paired control group (1:5 ratio). Five small nightclubs with indoor areas and outdoor terraces, in a nightlife-restricted area in Sitges, Spain, on 20 May 2021. Wearing masks was mandatory, drinking was allowed and social distance was not required. Volunteers were selected through a convenience sampling. To attend the event, participants were required to be older than 17 years, with a negative rapid antigen diagnostic test (Ag-RDT) on the same afternoon, without a positive reverse-transcription PCR (RT-PCR) or Ag-RDT and/or symptoms associated with COVID-19 in the previous 7 days, to not having knowingly been in close contact with someone infected in the previous 10 days and to not have knowingly had close contact with someone with a suspicion of COVID-19 in the previous 48 hours. A control group was paired by exact age, gender, residence municipality, socioeconomic index, previous SARS-CoV-2-confirmed infection and vaccination status, in a 1:5 ratio, from the primary care electronic health records. Evidence of infection at electronic health records by SARS-CoV-2 at 14-day follow-up. Among the 391 participants (median age 37 years; 44% (n=173) women), no positive SARS-CoV-2 cases were detected at 14 days, resulting in a cumulative incidence estimation of 0 (95% CI 0 to 943) per 100 000 inhabitants. In the control group, two cases with RT-PCR test were identified, resulting in a cumulative incidence of 102.30 (12.4 to 369) per 100 000 inhabitants. Nightlife attendance under controlled conditions and with a requirement for a negative Ag-RDT was not associated with increased transmissibility of SARS-CoV-2 in a pandemic context of low infection rates. In such circumstances, secure opening of the nightlife sector was possible, under reduced capacity and controlled access by Ag-RDT, and environments where compliance with sanitary measures are maintainable

    Total and high molecular weight adiponectin have similar utility for the identification of insulin resistance

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    <p>Abstract</p> <p>Background</p> <p>Insulin resistance (IR) and related metabolic disturbances are characterized by low levels of adiponectin. High molecular weight adiponectin (HMWA) is considered the active form of adiponectin and a better marker of IR than total adiponectin. The objective of this study is to compare the utility of total adiponectin, HMWA and the HMWA/total adiponectin index (S<sub>A </sub>index) for the identification of IR and related metabolic conditions.</p> <p>Methods</p> <p>A cross-sectional analysis was performed in a group of ambulatory subjects, aged 20 to 70 years, in Mexico City. Areas under the receiver operator characteristic (ROC) curve for total, HMWA and the S<sub>A </sub>index were plotted for the identification of metabolic disturbances. Sensitivity and specificity, positive and negative predictive values, and accuracy for the identification of IR were calculated.</p> <p>Results</p> <p>The study included 101 men and 168 women. The areas under the ROC curve for total and HMWA for the identification of IR (0.664 <it>vs</it>. 0.669, <it>P </it>= 0.74), obesity (0.592 <it>vs</it>. 0.610, <it>P </it>= 0.32), hypertriglyceridemia (0.661 <it>vs</it>. 0.671, <it>P </it>= 0.50) and hypoalphalipoproteinemia (0.624 <it>vs</it>. 0.633, <it>P </it>= 0.58) were similar. A total adiponectin level of 8.03 μg/ml was associated with a sensitivity of 57.6%, a specificity of 65.9%, a positive predictive value of 50.0%, a negative predictive value of 72.4%, and an accuracy of 62.7% for the diagnosis of IR. The corresponding figures for a HMWA value of 4.25 μg/dl were 59.6%, 67.1%, 51.8%, 73.7% and 64.2%.</p> <p>The area under the ROC curve of the S<sub>A </sub>index for the identification of IR was 0.622 [95% CI 0.554-0.691], obesity 0.613 [95% CI 0.536-0.689], hypertriglyceridemia 0.616 [95% CI 0.549-0.683], and hypoalphalipoproteinemia 0.606 [95% CI 0.535-0.677].</p> <p>Conclusions</p> <p>Total adiponectin, HMWA and the S<sub>A </sub>index had similar utility for the identification of IR and metabolic disturbances.</p
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