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1.
Artigo em Inglês | MEDLINE | ID: mdl-38306305

RESUMO

ABSTRACT: Effective communication in health care education is essential for creating an inclusive learning environment. This manuscript examines the crucial role of communication in physician assistant/associate (PA) education, particularly in the context of neurodiverse individuals, who constitute approximately 20% of the global population. A groundbreaking study by Nouri et al reveals a 3.1% overall disability prevalence among US practicing physicians, emphasizing the necessity for a comprehensive understanding of diversity in the health care profession. Considering the intersectionality of marginalized identities, this research sheds light on potential challenges health care providers face, underscoring the importance of promoting inclusivity and support for neurodiverse individuals in the PA profession. The increasing presence of neurodivergent students in postsecondary institutions, despite academic strengths, holds relevance for PA education. Recognizing the barriers and stigmas associated with neurodiversity is crucial for fostering inclusive environments within PA programs and sponsoring institutions. This manuscript explores the challenges faced by neurodiverse individuals in PA education and proposes strategies for cultivating a neuroinclusive culture through effective communication. With a focus on celebrating and using the strengths of all learners, regardless of neurodiversity, the overarching goal is to contribute to a paradigm shift in PA education, enriching the educational experience for students, educators, and support staff.

2.
J Physician Assist Educ ; 35(1): 116-119, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37878612

RESUMO

ABSTRACT: On Thursday, June 27, 2023, the US Supreme Court struck down race-conscious admission practices in higher education. While other demographic factors, such as the traditional Health Resources and Services Administration-disadvantaged background indicators, can be considered during the holistic admission process, explicit consideration based on race and/or ethnicity is prohibited. As a result, physician assistant/associate (PA) programs are tasked with developing novel ways to address equity, diversity, and inclusion during the admission and hiring processes. As Drumgold et al note, closing the PA workforce diversity gap is necessary to achieve health equity. Despite this, PA programs consistently struggle to attract and retain underrepresented in medicine (URiM) faculty, staff, and students. The latest PA Education Association Student Report indicates that more than 75% of applicants consider faculty and student body diversity when applying to programs. As such, addressing disparities in the recruitment, promotion, evaluation, and retention of URiM faculty is paramount. Here, the authors outline ongoing recruitment and retention challenges for URiM faculty along with institutional recommendations to ensure URiM PA faculty success and engagement.


Assuntos
Equidade em Saúde , Assistentes Médicos , Estados Unidos , Humanos , Assistentes Médicos/educação , Etnicidade , Docentes de Medicina , Seleção de Pessoal
3.
Environ Sci Pollut Res Int ; 30(23): 64094-64110, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37061635

RESUMO

Municipal wastewater effluent is one of the largest sources of pollution entering surface waters in the Laurentian Great Lakes. Exposure to wastewater effluent has been associated with impaired immune systems and induction of genotoxicity to aquatic animals. Due to habitat degradation and environmental pollution linked to industrial development and population growth, several regions of the Great Lakes have been designated Areas of Concern (AOCs). In this study, we assessed the effect of extracts of sewage influent, (treated) effluent and receiving surface waters from the Hamilton Harbour AOC and the Toronto and Region AOC (Ontario, Canada) on the phagocytic immune response of rainbow trout (Oncorhynchus mykiss) kidney leukocytes and the genotoxicity (DNA strand breaks) of these extracts on freshwater mussel (Eurynia dilatata) hemocytes. We identified and quantified numerous chemicals present in the various samples extracted for exposure. In freshwater mussels, extracts from Hamilton Harbour AOC induced DNA damage with the most frequency (12 out of 28 samples) regardless of sample type, reflecting past and present industrial activities. In contrast, extracts from Toronto and Region AOC induced DNA damage infrequently (2 out of 32 (summer) and 5 out of 32 (fall) samples, respectively) and from different WWTPs at different times. None of the extracts induced any significant effect on phagocytosis of rainbow trout kidney leukocytes. The present study indicates that despite overall improvements to effluent quality, treatment of influent by WWTPs may not result in a corresponding improvement of the genotoxicity of effluents. In vitro bioassays are useful and cost-effective rapid-screening tools for preliminary assessments of contamination of aquatic ecosystems.


Assuntos
Bivalves , Poluentes Químicos da Água , Animais , Águas Residuárias , Ecossistema , Organismos Aquáticos , Ontário , Dano ao DNA , Água Doce , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise
4.
Sci Total Environ ; 848: 157676, 2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-35926600

RESUMO

The extraction of surface mined bitumen from oil sands deposits in northern Alberta, Canada produces large quantities of liquid tailings waste, termed oil sands process-affected water (OSPW), which are stored in large tailings ponds. OSPW-derived chemicals from several tailings ponds migrating past containment structures and through groundwater systems pose a concern for surface water contamination. The present study investigated the toxicity of groundwater from near-field sites adjacent to a tailings pond with OPSW influence and far-field sites with only natural oil sands bitumen influence. The acute toxicity of unfractionated groundwater and isolated organic fractions was assessed using a suite of aquatic organisms (Pimephales promelas, Oryzias latipes, Daphnia magna, Hyalella azteca, Lampsilis spp., Ceriodaphnia dubia, Hexagenia spp., and Vibrio fischeri). Assessment of unfractionated groundwater demonstrated toxicity towards all invertebrates in at least one far-field sample, with both near-field and far-field samples with bitumen influence toxic towards P. promelas, while no toxicity was observed for O. latipes. When assessing the unfractionated groundwater and isolated organic fractions from near-field and far-field groundwater sites, P. promelas and H. azteca were the most sensitive to organic components, while D. magna and L. cardium were most sensitive to the inorganic components. Groundwater containing appreciable amounts of dissolved organics exhibited similar toxicities to sensitive species regardless of an OSPW or natural bitumen source. The lack of a clear distinction in relative acute toxicities between near-field and far-field samples indicates that the water-soluble chemicals associated with bitumen are acutely toxic to several aquatic organisms. This result, combined with the similarities in chemical profiles between bitumen-influenced groundwater originating from OSPW and/or natural sources, suggests that the industrial bitumen extraction processes corresponding to the tailings pond in this study are not contributing unique toxic substances to groundwater, relative to natural bitumen compounds present in groundwater flow systems.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Alberta , Animais , Organismos Aquáticos , Hidrocarbonetos , Campos de Petróleo e Gás , Água , Poluentes Químicos da Água/análise
6.
Nat Commun ; 13(1): 1441, 2022 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-35301339

RESUMO

Immune evasion is key to cancer initiation and later at metastasis, but its dynamics at intermediate stages, where potential therapeutic interventions could be applied, is undefined. Here we show, using multi-dimensional analyses of resected tumours, their adjacent non-tumour tissues and peripheral blood, that extensive immune remodelling takes place in patients with stage I to III hepatocellular carcinoma (HCC). We demonstrate the depletion of anti-tumoural immune subsets and accumulation of immunosuppressive or exhausted subsets along with reduced tumour infiltration of CD8 T cells peaking at stage II tumours. Corresponding transcriptomic modification occur in the genes related to antigen presentation, immune responses, and chemotaxis. The progressive immune evasion is validated in a murine model of HCC. Our results show evidence of ongoing tumour-immune co-evolution during HCC progression and offer insights into potential interventions to reverse, prevent or limit the progression of the disease.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Linfócitos T CD8-Positivos , Carcinoma Hepatocelular/patologia , Humanos , Evasão da Resposta Imune , Neoplasias Hepáticas/patologia , Camundongos , Transcriptoma
7.
J Physician Assist Educ ; 32(4): 242-247, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34817428

RESUMO

PURPOSE: The literature suggests that graduating medical and physician assistant (PA) students lack competency in electrocardiogram (ECG) interpretation. This project aimed to determine whether use of perceptual adaptive learning modules (PALMs) would improve PA students' ECG interpretation, alter self-perceptions of their ECG education, or both. METHODS: PALMs were incorporated into the PA curriculum after lecture-based ECG learning. Students' pretest, posttest, and delayed-posttest scores were then compared. Students' ability to correctly interpret ECGs (accuracy) and the percentage of ECGs accurately interpreted within 15 seconds or less (fluency) also were evaluated. Finally, students' perceptions of PALMs and overall ECG training were assessed. RESULTS: PALM training improved ECG interpretation accuracy and fluency (p < .0001), as well as delayed-posttest accuracy and fluency (p < .0001). The majority of student respondents felt supplemental training enhanced their learning. CONCLUSION: These perception results combined with data on ECG interpretation improvement supports continued use of supplemental PALMs in ECG interpretation training.


Assuntos
Educação de Graduação em Medicina , Assistentes Médicos , Competência Clínica , Eletrocardiografia , Humanos , Assistentes Médicos/educação , Estudantes
9.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33723044

RESUMO

Candida albicans is the most common cause of systemic fungal infections in humans and is considerably more virulent than its closest known relative, Candida dubliniensis. To investigate this difference, we constructed interspecies hybrids and quantified mRNA levels produced from each genome in the hybrid. This approach systematically identified expression differences in orthologous genes arising from cis-regulatory sequence changes that accumulated since the two species last shared a common ancestor, some 10 million y ago. We documented many orthologous gene-expression differences between the two species, and we pursued one striking observation: All 15 genes coding for the enzymes of glycolysis showed higher expression from the C. albicans genome than the C. dubliniensis genome in the interspecies hybrid. This pattern requires evolutionary changes to have occurred at each gene; the fact that they all act in the same direction strongly indicates lineage-specific natural selection as the underlying cause. To test whether these expression differences contribute to virulence, we created a C. dubliniensis strain in which all 15 glycolysis genes were produced at modestly elevated levels and found that this strain had significantly increased virulence in the standard mouse model of systemic infection. These results indicate that small expression differences across a deeply conserved set of metabolism enzymes can play a significant role in the evolution of virulence in fungal pathogens.


Assuntos
Evolução Biológica , Candida/classificação , Candida/genética , Seleção Genética , Alelos , Candida/metabolismo , Candida/patogenicidade , Candidíase/microbiologia , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Ontologia Genética , Genes Fúngicos , Hibridização Genética , Virulência/genética
10.
J Physician Assist Educ ; 32(1): 33-37, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33605687

RESUMO

PURPOSE: The clinical phase of physician assistant (PA) education has been reported to be the best time period to deliver opioid prescribing education (OPE) and opioid addiction education (OAE); however, there are no current published studies that evaluate the timing of OPE and OAE instruction in PA curricula. METHODS: This pilot study compared didactic and clinical phase cohorts' perceived confidence in their ability to evaluate patients with opioid use disorder (OUD) after receiving identical training at different time points within the curriculum. RESULTS: As expected, clinical phase students displayed high confidence levels in their abilities both before and after implementation of OUD-focused patient simulations. Interestingly, didactic phase students' confidence levels were comparable to clinical phase students' confidence levels after participating in the patient simulations. CONCLUSIONS: Our findings suggest that students can benefit from this training in both phases of the curriculum, which may encourage and help PA programs to insert this important and timely information into their curriculum.


Assuntos
Transtornos Relacionados ao Uso de Opioides , Assistentes Médicos , Analgésicos Opioides/uso terapêutico , Currículo , Humanos , Transtornos Relacionados ao Uso de Opioides/terapia , Percepção , Assistentes Médicos/educação , Projetos Piloto , Padrões de Prática Médica , Estudantes
11.
Int J Infect Dis ; 94: 125-127, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32304822

RESUMO

OBJECTIVE: This is a brief report of 4 paediatric cases of COVID-19 infection in Malaysia BACKGROUND: COVID-19, a coronavirus, first detected in Wuhan, China has now spread rapidly to over 60 countries and territories around the world, infecting more than 85000 individuals. As the case count amongst children is low, there is need to report COVID-19 in children to better understand the virus and the disease. CASES: In Malaysia, until end of February 2020, there were four COVID-19 paediatric cases with ages ranging from 20 months to 11 years. All four cases were likely to have contracted the virus in China. The children had no symptoms or mild flu-like illness. The cases were managed symptomatically. None required antiviral therapy. DISCUSSION: There were 2 major issues regarding the care of infected children. Firstly, the quarantine of an infected child with a parent who tested negative was an ethical dilemma. Secondly, oropharyngeal and nasal swabs in children were at risk of false negative results. These issues have implications for infection control. Consequently, there is a need for clearer guidelines for child quarantine and testing methods in the management of COVID-19 in children.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Betacoronavirus/isolamento & purificação , COVID-19 , Criança , Pré-Escolar , Infecções por Coronavirus/virologia , Feminino , Humanos , Lactente , Malásia , Masculino , Pneumonia Viral/virologia , SARS-CoV-2
12.
PLoS One ; 14(6): e0218037, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31170229

RESUMO

Candida albicans, a species of fungi, can thrive in diverse niches of its mammalian hosts; it is a normal resident of the GI tract and mucosal surfaces but it can also enter the bloodstream and colonize internal organs causing serious disease. The ability of C. albicans to thrive in these different host environments has been attributed, at least in part, to its ability to assume different morphological forms. In this work, we examine one such morphological change known as white-opaque switching. White cells are the default state of C. albicans, and most animal studies have been carried out exclusively with white cells. Here, we compared the proliferation of white and opaque cells in two murine models of infection and also monitored, using specially constructed strains, switching between the two states in the host. We found that white cells outcompeted opaque cells in many niches; however, we show for the first time that in some organs (specifically, the heart and spleen), opaque cells competed favorably with white cells and, when injected on their own, could colonize these organs. In environments where the introduced white cells outcompeted the introduced opaque cells, we observed high rates of opaque-to-white switching. We did not observe white-to-opaque switching in any of the niches we examined.


Assuntos
Candida albicans/citologia , Candida albicans/patogenicidade , Candidíase/microbiologia , Especificidade de Órgãos , Pigmentação , Animais , Candidíase/patologia , Contagem de Colônia Microbiana , Modelos Animais de Doenças , Corantes Fluorescentes/metabolismo , Intestinos/microbiologia , Intestinos/patologia , Rim/microbiologia , Rim/patologia , Camundongos
13.
JAAPA ; 30(5): 23-27, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28441669

RESUMO

Cystic fibrosis (CF) affects more than 30,000 people in the United States and 80,000 people worldwide. This life-threatening genetic disorder causes a buildup of thick, viscous mucus secretions in various organ systems, most commonly the gastrointestinal, pulmonary, and genitourinary systems. This article reviews the clinical manifestations, diagnosis, and monitoring of patients with CF as well as guidelines for management and emerging pharmacologic treatments.


Assuntos
Fibrose Cística/fisiopatologia , Fibrose Cística/terapia , Drenagem Postural/métodos , Respiração , Terapia Respiratória/métodos , Cloretos/análise , Fibrose Cística/diagnóstico , Humanos , Recém-Nascido , Triagem Neonatal/métodos , Prognóstico , Sudorese/fisiologia
14.
J Immigr Minor Health ; 19(1): 228-235, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-26454743

RESUMO

Despite the strong evidence for screening mammography in reducing mortality from breast cancer, uptake is hampered especially in recent immigrant populations. Although mammography screening behaviors of immigrant populations compared to the general population have been widely studied, evidence of the specific characteristics within the immigrant population in a universal healthcare setting, which explain differential uptake is lacking. The current cross sectional study used self-reported data from the 2011-2012 Canadian Community Health Survey to examine the association between recency of immigration and mammography uptake among 1825 immigrant women aged 50-69 years, using multivariable logistic model adjusted for confounders. In the adjusted analysis, non-recent immigrants had a nonsignificantly increased odds of recent mammography uptake, 1.19 (95 % CI 0.41, 3.44) compared to recent immigrants. In the face of evidence depicting differential health care utilization of recent immigrants compared to non-recent ones or the general population, findings from this study highlight further thinking into strategies for improving the health of immigrants.


Assuntos
Emigrantes e Imigrantes/estatística & dados numéricos , Emigração e Imigração/estatística & dados numéricos , Mamografia/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/etnologia , Idoso , Canadá , Estudos Transversais , Feminino , Pesquisas sobre Atenção à Saúde , Inquéritos Epidemiológicos , Humanos , Pessoa de Meia-Idade , Fatores Socioeconômicos , Fatores de Tempo
15.
West J Nurs Res ; 38(6): 704-20, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26809884

RESUMO

African Americans suffer disproportionately from smoking-related morbidity and mortality and make more quit attempts but report less success in quitting. Smokers tend to identify more strongly with African American culture. Qualitative interviews were conducted to elicit perceptions toward smoking and intervention content. Seventy-one African American smokers recruited from community locations participated. The majority stated they would not use any cessation aids if trying to quit smoking, despite the availability of free nicotine replacement. Acculturative stress scores were significantly higher in younger participants and those with higher income. Higher African American acculturation did not predict smoking cessation intervention preference. Family and social relationships were cited as both reasons for wanting to quit and reasons for continuing to smoke. Based on these findings, interventions for urban African Americans should address household members continuing to smoke, social/family connections, stress management, and cultural identification in urban areas.


Assuntos
Negro ou Afro-Americano/psicologia , Abandono do Hábito de Fumar/psicologia , População Urbana , Aculturação , Feminino , Promoção da Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Fumar/etnologia , Fumar/psicologia , Abandono do Hábito de Fumar/etnologia
16.
PLoS One ; 10(5): e0125353, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25945933

RESUMO

Cyanobacterial harmful algal blooms (cyanoHABs) are a primary source of water quality degradation in eutrophic lakes. The occurrence of cyanoHABs is ubiquitous and expected to increase with current climate and land use change scenarios. However, it is currently unknown what environmental parameters are important for indicating the presence of cyanoHAB toxins making them difficult to predict or even monitor on time-scales relevant to protecting public health. Using qPCR, we aimed to quantify genes within the microcystin operon (mcy) to determine which cyanobacterial taxa, and what percentage of the total cyanobacterial community, were responsible for microcystin production in four eutrophic lakes. We targeted Microcystis-16S, mcyA, and Microcystis, Planktothrix, and Anabaena-specific mcyE genes. We also measured microcystins and several biological, chemical, and physical parameters--such as temperature, lake stability, nutrients, pigments and cyanobacterial community composition (CCC)--to search for possible correlations to gene copy abundance and MC production. All four lakes contained Microcystis-mcyE genes and high percentages of toxic Microcystis, suggesting Microcystis was the dominant microcystin producer. However, all genes were highly variable temporally, and in few cases, correlated with increased temperature and nutrients as the summer progressed. Interestingly, toxin gene abundances (and biomass indicators) were anti-correlated with microcystin in all lakes except the largest lake, Lake Mendota. Similarly, gene abundance and microcystins differentially correlated to CCC in all lakes. Thus, we conclude that the presence of microcystin genes are not a useful tool for eliciting an ecological role for toxins in the environment, nor are microcystin genes (e.g. DNA) a good indicator of toxins in the environment.


Assuntos
Toxinas Bacterianas/metabolismo , Proliferação Nociva de Algas , Microcistinas/genética , Microcystis/classificação , Microcystis/genética , Anabaena/classificação , Anabaena/genética , Anabaena/patogenicidade , Biomassa , DNA Bacteriano/genética , Lagos/microbiologia , Microcistinas/metabolismo , Microcystis/patogenicidade , Reação em Cadeia da Polimerase , Wisconsin
18.
J Allergy Clin Immunol ; 136(2): 454-61.e9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25748343

RESUMO

BACKGROUND: The mechanisms underlying glucocorticoid responsiveness are largely unknown. Although redox regulation of the glucocorticoid receptor (GR) has been reported, it has not been studied in asthmatic patients. OBJECTIVE: We characterized systemic cysteine oxidation and its association with inflammatory and clinical features in healthy children and children with difficult-to-treat asthma. We hypothesized that cysteine oxidation would be associated with increased markers of oxidative stress and inflammation, increased features of asthma severity, decreased clinically defined glucocorticoid responsiveness, and impaired GR function. METHODS: PBMCs were collected from healthy children (n = 16) and children with asthma (n = 118) aged 6 to 17 years. Children with difficult-to-treat asthma underwent glucocorticoid responsiveness testing with intramuscular triamcinolone. Cysteine, cystine, and inflammatory chemokines and reactive oxygen species generation were quantified, and expression and activity of the GR were assessed. RESULTS: Cysteine oxidation was present in children with difficult-to-treat asthma and accompanied by increased reactive oxygen species generation and increased CCL3 and CXCL1 mRNA expression. Children with the greatest extent of cysteine oxidation had more features of asthma severity, including poorer symptom control, greater medication use, and less glucocorticoid responsiveness despite inhaled glucocorticoid therapy. Cysteine oxidation also modified the GR protein by decreasing available sulfhydryl groups and decreasing nuclear GR expression and activity. CONCLUSIONS: A highly oxidized cysteine redox state promotes a posttranslational modification of the GR that might inhibit its function. Given that cysteine oxidation is prevalent in children with difficult-to-treat asthma, the cysteine redox state might represent a potential therapeutic target for restoration of glucocorticoid responsiveness in this population.


Assuntos
Asma/tratamento farmacológico , Glucocorticoides/uso terapêutico , Leucócitos Mononucleares/imunologia , Processamento de Proteína Pós-Traducional , Receptores de Glucocorticoides/imunologia , Triancinolona/uso terapêutico , Administração por Inalação , Adolescente , Asma/genética , Asma/imunologia , Asma/patologia , Quimiocina CCL3/genética , Quimiocina CCL3/imunologia , Quimiocina CXCL1/genética , Quimiocina CXCL1/imunologia , Criança , Cisteína/química , Cisteína/imunologia , Cistina/química , Cistina/imunologia , Monitoramento de Medicamentos , Feminino , Expressão Gênica , Humanos , Injeções Intramusculares , Leucócitos Mononucleares/química , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/patologia , Masculino , Oxirredução , Estresse Oxidativo , Cultura Primária de Células , RNA Mensageiro/genética , RNA Mensageiro/imunologia , Receptores de Glucocorticoides/química , Receptores de Glucocorticoides/genética
19.
Sci Total Environ ; 487: 537-44, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24813769

RESUMO

Pharmaceuticals and personal care products (PPCPs) and their metabolites are continually released from wastewater treatment plants into the aquatic environment; however, their impact on aquatic biota is poorly understood. This study examined the toxicity and bioconcentration of three pharmaceuticals: moxifloxacin, rosuvastatin, and drospirenone to the unionid mussel Lampsilis siliquoidea. Effects of moxifloxacin and rosuvastatin were assessed through aqueous 21-d static-renewal tests using 2-year-old mussels, at 0.01, 0.1, 1, 10 and 100mg/L (nominal concentrations). Following exposure, survival, behavior, algal clearance rate, hemocyte viability and density, and glutathione S-transferase (GST) activity were assessed. In addition, the acute (48 h) toxicity of moxifloxacin (0-100mg/L) and drospirenone (0-3mg/L) to glochidia (larval mussels) were examined. In 21 day exposures (2-yr old mussels), there were no differences in survival, oxygen consumption, hemocyte density, or GST activity over the range of concentrations examined; however, the proportion of time mussels spent filtering, and consequently the algal clearance rate, decreased at the higher moxifloxacin and rosuvastatin concentrations. Bioconcentration factors (BCFs) ranged between 0.03 and 70 for moxifloxacin, and between 0 and 0.05 for rosuvastatin for exposures up to 100mg/L. The BCF for moxifloxacin at the highest exposure concentration was lower than that at the mid-level concentrations, likely due to decreased filtering activity at the higher exposure levels. The feeding rates declined and the amount of time the subadult mussels spent with their valves closed increased at the higher moxifloxacin and rosuvastatin exposures. Glochidia viability did not vary with exposure to drospirenone, but declined at the highest moxifloxacin concentration, resulting in an EC50 of 120 mg/L. Overall, observed sublethal and lethal effects occurred at concentrations which exceed expected environmental concentrations through aqueous exposure, suggesting a low risk to freshwater mussels from these particular PPCPs.


Assuntos
Androstenos/toxicidade , Fluorbenzenos/toxicidade , Fluoroquinolonas/toxicidade , Pirimidinas/toxicidade , Sulfonamidas/toxicidade , Poluentes Químicos da Água/toxicidade , Androstenos/metabolismo , Animais , Fluorbenzenos/metabolismo , Fluoroquinolonas/metabolismo , Glutationa Transferase/metabolismo , Moxifloxacina , Pirimidinas/metabolismo , Medição de Risco , Rosuvastatina Cálcica , Sulfonamidas/metabolismo , Unionidae/fisiologia , Poluentes Químicos da Água/metabolismo
20.
PLoS One ; 8(9): e74933, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24086400

RESUMO

Spatial and temporal variability in cyanobacterial community composition (CCC) within and between eutrophic lakes is not well-described using culture independent molecular methods. We analyzed CCC across twelve locations in four eutrophic lakes and within-lake locations in the Yahara Watershed, WI, on a weekly basis, for 5 months. Taxa were discriminated by length of MspI-digested cpcB/A intergenic spacer gene sequences and identified by comparison to a PCR-based clone library. CCC across all stations was spatially segregated by depth of sampling locations (ANOSIM R = 0.23, p < 0.001). Accordingly, CCC was correlated with thermal stratification, nitrate and soluble reactive phosphorus (SRP, R = 0.2-0.3). Spatial variability in CCC and temporal trends in taxa abundances were rarely correlative between sampling locations in the same lake indicating significant within lake spatiotemporal heterogeneity. Across all stations, a total of 37 bloom events were observed based on distinct increases in phycocyanin. Out of 97 taxa, a single Microcystis, and two different Aphanizomenon taxa were the dominant cyanobacteria detected during bloom events. The Microcystis and Aphanizomenon taxa rarely bloomed together and were significantly anti-correlated with each other at 9 of 12 stations with Pearson R values of -0.6 to -0.9 (p < 0.001). Of all environmental variables measured, nutrients, especially nitrate were significantly greater during periods of Aphanizomenon dominance while the nitrate+nitrite:SRP ratio was lower. This study shows significant spatial variability in CCC within and between lakes structured by depth of the sampling location. Furthermore, our study reveals specific genotypes involved in bloom formation. More in-depth characterization of these genotypes should lead to a better understanding of factors promoting bloom events in these lakes and more reliable bloom prediction models.


Assuntos
Aphanizomenon/fisiologia , Eutrofização , Microcystis/fisiologia , Análise Espaço-Temporal , Geografia , Lagos/química , Lagos/microbiologia , Interações Microbianas , Ficocianina/metabolismo , Solubilidade , Temperatura , Fatores de Tempo , Wisconsin
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