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1.
Aquat Toxicol ; 238: 105927, 2021 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-34340001

RESUMEN

Active substances of pesticides, biocides or pharmaceuticals can induce adverse side effects in the aquatic ecosystem, necessitating environmental hazard and risk assessment prior to substance registration. The freshwater crustacean Daphnia magna is a model organism for acute and chronic toxicity assessment representing aquatic invertebrates. However, standardized tests involving daphnia are restricted to the endpoints immobility and reproduction and thus provide only limited insights into the underlying modes-of-action. Here, we applied transcriptome profiling to a modified D. magna Acute Immobilization test to analyze and compare gene expression profiles induced by the GABA-gated chloride channel blocker fipronil and the nicotinic acetylcholine receptor (nAChR) agonist imidacloprid. Daphnids were expose to two low effect concentrations of each substance followed by RNA sequencing and functional classification of affected gene ontologies and pathways. For both insecticides, we observed a concentration-dependent increase in the number of differentially expressed genes, whose expression changes were highly significantly positively correlated when comparing both test concentrations. These gene expression fingerprints showed virtually no overlap between the test substances and they related well to previous data of diazepam and carbaryl, two substances targeting similar molecular key events. While, based on our results, fipronil predominantly interfered with molecular functions involved in ATPase-coupled transmembrane transport and transcription regulation, imidacloprid primarily affected oxidase and oxidoreductase activity. These findings provide evidence that systems biology approaches can be utilized to identify and differentiate modes-of-action of chemical stressors in D. magna as an invertebrate aquatic non-target organism. The mechanistic knowledge extracted from such data will in future contribute to the development of Adverse Outcome Pathways (AOPs) for read-across and prediction of population effects.

2.
Artículo en Inglés | MEDLINE | ID: mdl-32645408

RESUMEN

Plants have evolved various acclimation responses to cope with phosphate depletion, including several changes in lipid metabolism. Thereby membrane phospholipids are dephosphorylated and can be used as an internal phosphate source, while galactolipids are incorporated into the membrane to maintain membrane functionality. Still little is known about the lipidomic and transcriptomic response of plants other than Arabidopsis thaliana upon phosphate starvation. Therefore, we employed lipidomics and transcriptomics to characterize the phosphate starvation response of lipid metabolism in tomato leaves and roots. Overall, phospholipid levels decreased and galactolipids increased during the acclimation response. In addition, an early increase of triacylglycerol was observed. Interestingly, there were major differences in the acclimation response of tomato leaves and roots: leaves mainly accumulated polyunsaturated triacylglycerol, while roots showed a massive increase in galactolipid content. In line with these results, we observed transcriptional induction of phospholipid degradation and galactolipid synthesis pathways in both analyzed tissues. In contrast, other aspects of the transcriptional response, in particular, the induction of phospholipid degradation, ER-localized fatty acid desaturation and triacylglycerol assembly differed between tomato leaves and roots. These results suggest a different modulation of degraded phospholipids toward triacylglycerols and galactolipids in phosphate-starved tomato leaves and roots. Possibly the availability and composition of acyl-CoA pools and ER-derived precursors trigger the synthesis of triacylglycerols or galactolipids. As the mechanism of triacylglycerol accumulation is poorly characterized outside of seed oil formation, these findings enhance our understanding of the phosphate starvation response and of how storage lipids accumulate under stress in vegetative tissue.


Asunto(s)
Metabolismo de los Lípidos , Fosfatos/deficiencia , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismo , Solanum lycopersicum/metabolismo , Retículo Endoplásmico/metabolismo , Estrés Fisiológico
3.
Biochem J ; 477(13): 2543-2559, 2020 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-32556082

RESUMEN

Algae have evolved several mechanisms to adjust to changing environmental conditions. To separate from their surroundings, algal cell membranes form a hydrophobic barrier that is critical for life. Thus, it is important to maintain or adjust the physical and biochemical properties of cell membranes which are exposed to environmental factors. Especially glycerolipids of thylakoid membranes, the site of photosynthesis and photoprotection within chloroplasts, are affected by different light conditions. Since little is known about membrane lipid remodeling upon different light treatments, we examined light induced alterations in the glycerolipid composition of the two Chlorella species, C. vulgaris and C. sorokiniana, which differ strongly in their ability to cope with different light intensities. Lipidomic analysis and isotopic labeling experiments revealed differences in the composition of their galactolipid species, although both species likely utilize galactolipid precursors originated from the endoplasmic reticulum. However, in silico research of de novo sequenced genomes and ortholog mapping of proteins putatively involved in lipid metabolism showed largely conserved lipid biosynthesis pathways suggesting species specific lipid remodeling mechanisms, which possibly have an impact on the response to different light conditions.


Asunto(s)
Luz , Lípidos de la Membrana/metabolismo , Chlorella/efectos de la radiación , Metabolismo de los Lípidos/efectos de la radiación , Oxígeno/metabolismo , Filogenia , ARN Ribosómico 18S/genética
4.
Am J Otolaryngol ; 40(3): 358-363, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30819541

RESUMEN

OBJECTIVE: Variation in weather patterns is often cited as a risk factor for epistaxis although robust studies investigating specific climate factors are lacking. As society is increasingly utilizing the Internet to learn more about their medical conditions, we explore whether Internet search activity related to epistaxis is influenced by fluctuations in climate. METHODS: Internet search activity for epistaxis-related search terms during 2012-2017 were extracted from Google Trends and localized to six highly populated cities in the US: New York, New York; Los Angeles, California; Chicago, Illinois; Houston, Texas; Philadelphia, Pennsylvania; and Atlanta, Georgia. Data were compared to local average monthly climate data from the National Centers for Environmental Information for the same time period. RESULTS: Spearmen correlations (r) were statistically strongest for dew point temperature (rNewYork = -0.82; rPhiladelphia = -0.74; rChicago = -0.65; rAtlanta = -0.49, rLosAngeles = -0.3). This was followed closely by relative humidity (rNewYork = -0.63; rPhiladelphia = -0.57; rLosAngeles = -0.44; rAtlanta = -0.42; rHouston = -0.40) and average temperature (rNewYork = -0.8; rPhiladelphia = -0.72; rChicago = -0.62; rAtlanta = -0.45). Overall, correlations were most significant and predictable for cities with the greatest seasonal climate shifts (New York, Philadelphia, and Chicago). The weakest environmental factor was barometric pressure, which was found to be moderately positive in Atlanta (rbarometric = 0.31), Philadelphia (rbarometric = 0.30) and New York (rbarometric = 0.27). CONCLUSIONS: Google Trends data for epistaxis-related search activity responds closely to climate patterns in most cities studied, thus underscoring the potential utility of Internet search activity data as a resource for epidemiologic study and for the identification of at risk populations.


Asunto(s)
Clima , Epistaxis/epidemiología , Internet/estadística & datos numéricos , Utilización de Procedimientos y Técnicas/estadística & datos numéricos , Motor de Búsqueda/estadística & datos numéricos , Población Urbana/estadística & datos numéricos , Tiempo (Meteorología) , Presión Atmosférica , Humanos , Humedad , Factores de Riesgo , Temperatura
5.
J Environ Manage ; 223: 409-416, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-29945102

RESUMEN

The water-energy-food (WEF) nexus is increasingly recognised as a conceptual framework able to support the efficient implementation of the Sustainable Development Goals (SDGs). Despite growing attention paid to the WEF nexus, the role that renewable energies can play in addressing trade-offs and realising synergies has received limited attention. Until now, the focus of WEF nexus discussions and applications has mainly been on national or global levels, macro-level drivers, material flows and large infrastructure developments. This overlooks the fact that major nexus challenges are faced at local level. Aiming to address these knowledge gaps, the authors conduct a systematic analysis of the linkages between small-scale energy projects in developing countries and the food and water aspects of development. The analysis is based on empirical data from continuous process and impact evaluations complemented by secondary data and relevant literature. The study provides initial insights into how to identify interconnections and the potential benefits of integrating the nexus pillars into local level projects in the global south. The study identifies the complex links which exist between sustainable energy projects and the food and water sectors and highlights that these needs are currently not systematically integrated into project design or project evaluation. A more systematic approach, integrating the water and food pillars into energy planning at local level in the global south, is recommended to avoid trade-offs and enhance the development outcomes and impacts of energy projects.


Asunto(s)
Conservación de los Recursos Naturales , Abastecimiento de Alimentos , Abastecimiento de Agua , Alimentos , Agua
6.
Otolaryngol Head Neck Surg ; 155(3): 508-13, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27188704

RESUMEN

OBJECTIVE: To determine the effect of ibuprofen on posttonsillectomy bleeding when compared with codeine in posttonsillectomy analgesia. STUDY DESIGN: Case series with chart review. SETTING: Tertiary care children's hospital, Philadelphia, Pennsylvania. SUBJECTS AND METHODS: On July 1, 2012, our institution transitioned from acetaminophen with codeine to ibuprofen for posttonsillectomy analgesia. Pediatric patients (0-18 years old) who underwent surgery from July 1, 2010, to June 30, 2012, were placed in the codeine cohort, and those who underwent surgery from July 1, 2012, to June 30, 2014, were placed in the ibuprofen cohort. RESULTS: A total of 6014 patients underwent tonsillectomy between July 1, 2010, and June 30, 2014, and 211 patients presented for posttonsillectomy hemorrhage during the same period. The incidence of readmission for posttonsillectomy hemorrhage was 3.4% and 3.6% (P = .63; odds ratio [OR] = 1.07; 95% confidence interval [95% CI]: 0.811-1.410) for the codeine and ibuprofen groups, respectively, and the incidence of second operation for control of posttonsillectomy bleeding for the codeine and ibuprofen groups was 1.9% and 2.2% (P = .54; OR = 1.117; 95% CI: 0.781-1.600), respectively. Patients aged 11 to 18 years demonstrated a higher incidence of posttonsillectomy bleeding events overall. When age is controlled, multivariate logistic regression demonstrated no statistically significant increase in posttonsillectomy bleeding events among pediatric patients treated with ibuprofen versus patients treated with codeine (readmission: P = .617; OR = 0.932; 95% CI: 0.707-1.228; reoperation: P = .513; OR = 0.887; 95% CI: 0.618-1.272). CONCLUSION: Age is an independent risk factor for posttonsillectomy bleeding. When age is controlled, there is no statistically significant increase in the incidence of posttonsillectomy bleeding events among patients treated with ibuprofen when compared to patients treated with codeine.


Asunto(s)
Analgésicos no Narcóticos/uso terapéutico , Analgésicos Opioides/uso terapéutico , Codeína/uso terapéutico , Ibuprofeno/uso terapéutico , Dolor Postoperatorio/prevención & control , Hemorragia Posoperatoria/inducido químicamente , Tonsilectomía , Adenoidectomía , Adolescente , Factores de Edad , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Readmisión del Paciente/estadística & datos numéricos , Factores de Riesgo
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