Search results for " Organism"

Manipulating mtDNA in vivo reprograms metabolism via novel response mechanisms.

2019

Mitochondria have been increasingly recognized as a central regulatory nexus for multiple metabolic pathways, in addition to ATP production via oxidative phosphorylation (OXPHOS). Here we show that inducing mitochondrial DNA (mtDNA) stress in Drosophila using a mitochondrially-targeted Type I restriction endonuclease (mtEcoBI) results in unexpected metabolic reprogramming in adult flies, distinct from effects on OXPHOS. Carbohydrate utilization was repressed, with catabolism shifted towards lipid oxidation, accompanied by elevated serine synthesis. Cleavage and translocation, the two modes of mtEcoBI action, repressed carbohydrate rmetabolism via two different mechanisms. DNA cleavage activ…

Endocrine disrupter compounds removal in wastewater using microalgae: Degradation kinetics assessment

2018

[EN] This paper describes a study carried out to determine the removal kinetics of four micropollutants (4-tert-octylphenol (OP), technical-nonylphenol (t-NP), 4-nonylphenol (4-NP) and bisphenol-A (BPA)) usually found in wastewater streams. The kinetic experiments were carried out in batch reactors containing the effluent of an Anaerobic Membrane BioReactor (AnMBR) in the presence of light, oxygen and microalgae. As the degradation process of the studied micropollutants obeyed a pseudo-first-order kinetics, the second-order kinetics for each micropollutant was then calculated. The second order rate constants for the hydroxyl radical (k.(OH)) ranged from 7.0.10(+10) to 6.6.10(+12) L.mol(-1).…

Morphological abnormalities induced by Fenoxycarb on the pupa ofPhanerotoma (Phanerotoma) ocularisKohl (Hym., Braconidae)

1993

Fenoxycarb at concentrations of 0.001 μg/ml, 0.005 μg/ml, 0.01 μg/ml, 0.05μg/ml and 0.1 μg/ml had an adverse effect on the pupa of Phanerotoma (Phanerotoma) ocularis. When topically applied, it induced morphological abnormalities. The percentage of anomalous obtained depended of developmental pupal stage and was higher when was applied in the first moment of development (80 %-90 %) than in the final of development (50%-60%). These anomalous was inviables. Zusammenfassung Morphologische Abnormitaten bei Puppen von Phanerotoma (Phanerotoma) ocularis Kohl (Hym., Braconidae) nach Einwirkung von Fenoxycarb Fenoxycarb, in Konzentrationen von 0.001 μg/ml, 0.0005 μg/ml, 0.01 μg/ml, 0.05 |μg/ml und …

Assessment of regional ventilation distribution: comparison of vibration response imaging (VRI) with electrical impedance tomography (EIT)

2013

BACKGROUND: Vibration response imaging (VRI) is a bedside technology to monitor ventilation by detecting lung sound vibrations. It is currently unknown whether VRI is able to accurately monitor the local distribution of ventilation within the lungs. We therefore compared VRI to electrical impedance tomography (EIT), an established technique used for the assessment of regional ventilation. METHODOLOGY/PRINCIPAL FINDINGS: Simultaneous EIT and VRI measurements were performed in the healthy and injured lungs (ALI; induced by saline lavage) at different PEEP levels (0, 5, 10, 15 mbar) in nine piglets. Vibration energy amplitude (VEA) by VRI, and amplitudes of relative impedance changes (rel.ΔZ) …

Biofabrication of biosilica-glass by living organisms

2008

Biosilicification is an evolutionarily old and widespread type of biomineralization both in unicellular and multicellular organisms, including sponges, diatoms, radiolarians, choanoflagellates, and higher plants. In the last few years combined efforts in molecular biology, cell biology, and inorganic and analytical chemistry have allowed the first insight into the molecular mechanisms by which these organisms form an astonishing variety of siliceous structures that cannot be achieved by chemical methods. Here we report about the present stage of knowledge on structure, biochemical composition, and mechanisms of biosilica formation, focusing our attention particularly on sponges because of t…

Developing and Integrating Advanced Movement Features Improves Automated Classification of Ciliate Species

2015

Recent advances in tracking technologies such as GPS or video tracking systems describe the movement paths of individuals in unprecedented details and are increasingly used in different fields, including ecology. However, extracting information from raw movement data requires advanced analysis techniques, for instance to infer behaviors expressed during a certain period of the recorded trajectory, or gender or species identity in case data is obtained from remote tracking. In this paper, we address how different movement features affect the ability to automatically classify the species identity, using a dataset of unicellular microbes (i.e., ciliates). Previously, morphological attributes a…

2019

Cancer remains one of the most lethal diseases worldwide. There is an urgent need for new drugs with novel modes of action and thus considerable research has been conducted for new anticancer drugs from natural sources, especially plants, microbes and marine organisms. Marine populations represent reservoirs of novel bioactive metabolites with diverse groups of chemical structures. This review highlights the impact of marine organisms, with particular emphasis on marine plants, algae, bacteria, actinomycetes, fungi, sponges and soft corals. Anti-cancer effects of marine natural products in in vitro and in vivo studies were first introduced; their activity in the prevention of tumor formatio…

Challenging fear: chemical alarm signals are not causing morphology changes in crucian carp (Carassius carassius)

2010

Published version of an article in the journal: Environmental Biology of Fishes. Also available at SpringerLink: http://dx.doi.org/10.1007/s10641-010-9707-9 Crucian carp develops a deep body in the presence of chemical cues from predators, which makes the fish less vulnerable to gape-limited predators. The active components originate in conspecifics eaten by predators, and are found in the filtrate of homogenised conspecific skin. Chemical alarm signals, causing fright reactions, have been the suspected inducers of such morphological changes. We improved the extraction procedure of alarm signals by collecting the supernatant after centrifugation of skin homogenates. This removes the minute …

La entrevista cualitativa como técnica de la evaluación de la docencia universitaria

2004

El presente artículo analiza el rol estratégico que juega el vector educativo en el alivio de la pobreza en el escenario actual. Para ello se articula en tres apartados: en primer lugar analiza cuáles son las acciones que surgen desde los organismos internacionales más significativos en la lucha contra la pobreza para pasar, en segundo, a revisar cuáles han sido, durante en la década de los años noventa, los discursos subyacentes a las reformas educativas, así como los tópicos emergentes de atención e interés dentro de las mismas. Finalmente, en la tercera parte, se plantea cuál es el estado de la cuestión que gira en torno a la pobreza en Latinoamérica y cómo está afectando a la educación,…

Besteht eine Beeinträchtigung der ZNS-Aktivität durch gepulste elektromagnetische Felder? - Do Pulsed Electromagnetic Fields Impair CNS Activity?

2001

In the present pilot study we examined the effects of electromagnetic fields on the biological organism. The study was prompted by discussions on the possible effects on the nervous system and cognitive processes of fields produced by mobile phones. The experiments were performed in an electrophysiological laboratory. Eleven volunteers were exposed to pulsed electromagnetic fields (GSM standard). The psychophysiological method of assessing the order threshold (Ordnungsschwelle = OS) was used to examine cognitive performance. Under the test conditions, nine of the subjects showed a loss of mental regeneration, as reflected by an increase in the OS, in comparison with the field-free situation…