89 research outputs found
A non-fatal potassium cyanide poisoning
Iznesen je slučaj otrovanja kalijevim cijanidom, kod kojega je pacijent uzeo per os u namjeri samoubistva približno petnaesterostruku letalnu dozu i ostao na životu. Komentirane su mogućnosti terapije. Iznesena je toksikologija cijanida, dijagnostički i terapeutski postupci.A case of potassium cyanide poisoning in a somatically healthy man, aged 24, is presented. With intention of committing suicide he swallowed 3.75 g of potassium cyanide (fifteen times the lethal dose) in a slice of bread. 30 minutes afterwards he was taken to the hospital in deep coma. After lavage of the stomach respiration stopped with slowing of the heart rate and extrasystolia. Artificial intratracheal breathing was applied, as well as the inhalation of amyl nitrite through 10 minutes (in the intervals of 2 minutes). This produced sporadic spontaneous respiration, and soon rhythmic respiration began. In half an hour the patient became conscious and was out of danger. The mechanism of intoxication and the therapy are discussed
The white collar complex is essential for sexual reproduction but dispensable for conidiation and invasive growth in Fusarium verticillioides
Fvwc1 and Fvwc2, orthologues of the wc-1 and wc-2 genes encoding for proteins of the white collar complex (WCC) in Neurospora crassa were cloned from Fusarium verticillioides and lack-of-function wc mutants were obtained by targeted gene disruption. Photo-conidiation was found to be absent in F. verticillioides, on the contrary, the wild type strain produced less conidia under continuous illumination than in the dark. Inactivation of any of the wc genes led to total female sterility, without affecting male fertility or asexual conidiation. No loss in colonization capability/invasive growth of the wc mutants was observed, when assessed on tomato fruits. Both Fvwc1 and Fvwc2 showed constitutive expression in the wild type cultures incubated in the dark and exposure to light caused only negligible increases in their transcription. Both Fvwc1 and Fvwc2 were down-regulated in a ΔFvmat1-2-1 gene disruption mutant, lacking a functional mating type (mat1-2-1) gene, suggesting that the MAT1-2-1 product has a positive regulatory effect on the white collar genes
Low oxygen affects photophysiology and the level of expression of two-carbon metabolism genes in the seagrass <i>Zostera muelleri</i>
© 2017, Springer Science+Business Media B.V. Seagrasses are a diverse group of angiosperms that evolved to live in shallow coastal waters, an environment regularly subjected to changes in oxygen, carbon dioxide and irradiance. Zostera muelleri is the dominant species in south-eastern Australia, and is critical for healthy coastal ecosystems. Despite its ecological importance, little is known about the pathways of carbon fixation in Z. muelleri and their regulation in response to environmental changes. In this study, the response of Z. muelleri exposed to control and very low oxygen conditions was investigated by using (i) oxygen microsensors combined with a custom-made flow chamber to measure changes in photosynthesis and respiration, and (ii) reverse transcription quantitative real-time PCR to measure changes in expression levels of key genes involved in C4 metabolism. We found that very low levels of oxygen (i) altered the photophysiology of Z. muelleri, a characteristic of C3 mechanism of carbon assimilation, and (ii) decreased the expression levels of phosphoenolpyruvate carboxylase and carbonic anhydrase. These molecular-physiological results suggest that regulation of the photophysiology of Z. muelleri might involve a close integration between the C3 and C4, or other CO2 concentrating mechanisms metabolic pathways. Overall, this study highlights that the photophysiological response of Z. muelleri to changing oxygen in water is capable of rapid acclimation and the dynamic modulation of pathways should be considered when assessing seagrass primary production
Glial ankyrins facilitate paranodal axoglial junction assembly
Neuron-glia interactions establish functional membrane domains along myelinated axons. These include nodes of Ranvier, paranodal axoglial junctions, and juxtaparanodes. Paranodal junctions are the largest vertebrate junctional adhesion complex, are essential for rapid saltatory conduction, and contribute to assembly and maintenance of nodes. However, the molecular mechanisms underlying paranodal junction assembly are poorly understood. Ankyrins are cytoskeletal scaffolds traditionally associated with Na+ channel clustering in neurons and important for membrane domain establishment and maintenance in many cell types. Here, we show that ankyrinB, expressed by Schwann cells, and ankyrinG, expressed by oligodendrocytes, are highly enriched at the glial side of paranodal junctions where they interact with the essential glial junctional component neurofascin 155. Conditional knockout of ankyrins in oligodendrocytes disrupts paranodal junction assembly and delays nerve conduction during early development in mice. Thus, glial ankyrins function as major scaffolds that facilitate early and efficient paranodal junction assembly in the developing central nervous system
Prediction of gas-particle partitioning of polycyclic aromatic hydrocarbons based on M5' model trees
During the thermal combustion processes of carbon-enriched organic compounds, emission of polycyclic aromatic hydrocarbons into ambient air occurs. Previous studies of atmospheric distribution of polycyclic aromatic hydrocarbons showed low correlation between the experimental values and Junge-Pankow theoretical adsorption model, suggesting that other approaches should be used to describe the partitioning phenomena. The paper evaluates the applicability of multivariate piece-wise-linear M5' model-tree models to the problem of gas-particle partitioning. Experimental values of particle-associated fraction, obtained for 129 ambient air samples collected at 24 background, urban, and industrial sites, were compared to the prediction results obtained using M5' and the Junge-Pankow model. The M5' approach proposed and models learned are able to achieve good correlation (correlation coefficient >0.9) for some low-molecular-weight compounds, when the target is to predict the concentration of gas phase based on the particle-associated phase. When converted to particle-bound fraction values, the results, for selected compounds, are superior to those obtained by Junge-Pankow model by several orders of magnitude, in terms of the prediction error
Assessment of atmospheric distribution of polychlorinated biphenyls and polycyclic aromatic hydrocarbons using polyparameter model
Results of partial or total destruction of industrial plants, military targets, infrastructure, uncontrolled fires and explosions during the conflict period from 1991 to 1999, at the area of Western Balkans, were large amounts of hazardous organic matter that have been generated and emitted in the environment. In order to assess gas/particle partition of seven EPA polychlorinated biphenyls and sixteen EPA polycyclic aromatic hydrocarbons, twenty air samples have been collected at six urban, industrial and highly contaminated localities in Vojvodina. Hi-Vol methodology has been used for collecting ambiental air samples, that simultaneously collects gaseous and particulate phase with polyurethane foam filters (PUF) and glass fiber filters (GFF). PUF and GFF filters have been analyzed, and concentration levels of gaseous PCBs and PAHs molecules in gaseous and particulate phase were obtained, converted and expressed through fraction of individual compounds sorbed onto particulate phase of the sample, in total detected quantity. Experimentally gained gas/particle partitioning values of PCBs and PAHs molecules have been compared with PP-LFER model estimated values. Significant deviation has been noticed during comparative analysis of estimated polyparameter model values for complete set of seven PCBs congeners. Much better agreement of experimental and estimated values is for polycyclic aromatic hydrocarbons, especially for molecules with four rings. These results are in a good correlation with literature data where polyparameter model has been used for predicting gas/particle partition of studied group of organic molecules
Industrial emerging chemicals in the environment
In the recent time, considerable interest has grown concerning the presence
of the emerging industrial chemicals, EmIC. They are contaminants that have
possible pathway to enter to the environment and they are dominantly released
by industrial and anthropogenic activities. EmIC are applied in different
fields using as industrial chemicals (new and recently recognized), global
organic contaminants (flame retardant chemicals), pharmaceuticals (for both
human and animal uses), endocrine-modulating compounds, biological
metabolites, personal care products, household chemicals, nanomaterial
(energy storage products, lubricants), anticorrosive and agriculture
chemicals and others that are applied to a wide variety of everyday items
such as clothing, upholstery, electronics and automobile interiors. NORMAN
(Network of reference laboratories for monitoring of emerging environmental
pollutants) has established an open, dynamic, list of emerging substances and
pollutants. EmIC have been recently detected in the environment due to their
long-term presence, pseudo-persistence and increased use. Improvements in
sophisticated analytical methods and time integrative passive sampling have
enabled the identification and quantification of EmIC, in very low
concentrations (ppb, ppt and lower), which likely have been present in all
environmental mediums for decades. Passive technology is an innovative
technique for the time-integrated measurement of emerging contaminants in
water, sediment, soil and air. Passive samplers are simple handling
cost-effective tool that could be used in environmental monitoring
programmes. These devices are now being considered as a part of an emerging
strategy for monitoring a range of emerging industrial chemicals and priority
pollutants in the aquatic environment. EmIC are substances that are not
included in the routine monitoring programmes and whose fate, behaviour and
(eco)toxicological effects are still not well understood. Emerging pollutants
have no regulatory standards based on peer-reviewed science. EmIC might
jeopardize aquatic environment. The first screening analyses of emerging
industrial and priority organic contaminants in the Danube surface water, in
the vicinity of Novi Sad, have been done and approximately more than 140
compounds have been registered. The new sampling campaign, screening and
target analyses are in progress. [Projekat Ministarstva nauke Republike
Srbije, br. III46009
DataSheet_1_Different life strategies of the three commercially exploited scallop species living under the same environmental conditions.docx
To understand the response of marine species to a changing environment, it is crucial to have deep insight into their main biological traits. This study used a multi-species approach to comparatively analyse the reproductive and growth strategies of three commercially important scallop species. Target taxa were larger sized Mediterranean scallop Pecten jacobeaus, and two smaller sized species Aequipecten opercularis and Flexopecten glaber. Specimens were collected at approximate monthly intervals from February 2017 to October 2018 from a commercial beam trawl in the northern Adriatic area (west coast of the Istria peninsula, 25-35 m depth). Three different complementary methods were applied to obtain comprehensive knowledge about the reproductive cycle including assessment of the gonadosomatic index (GSI), histological analysis of gonad tissue, and measuring oocyte size. Growth strategies of three target species were analyzed using high-resolution stable oxygen isotope data that were temporally aligned on sea water temperature data obtained by AdriSC ROMS model. Results indicate diverse strategies employed by these taxonomically related species exposed to the same environmental conditions. Pecten jacobaeus spawned in the late summer and early fall, while shell growth slowed down during warmer season. Aequipecten opercularis spawned in the winter and slowed down shell deposition process during the cold season. Spawning of F. glaber occurred during early to mid-summer and growth slowed down during warmer season. This study provides an important scientific baseline for sustainable management and future aquaculture attempts of scallops.</p
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