Frozen mitochondria as rapid water quality bioassay

A rapid and relatively low cost bioassay, usable in routine screening water test has been developed modifying the beef heart mitochondria test. In our experiments, mitochondria (FM22) were frozen at 22 °C, instead of 80 °C (FM80), and their applicability and sensitivity was verified. The oxygen consumption was measured by a Clark elec- trode that was interfaced to a PC to collect test analysis data. Blank tests were carried out to verify the oxygen con- sumption linear fitting. Toxicity tests were performed using pure organic and inorganic compounds, such to verify the FM22 sensitivity. A piecewise regression, through an Excelâ Macro, identified the break-point in the oxygen con- sumption and calculated the toxicity. The IC50s of the tested compounds were calculated and ranged from 0.123 to 0.173 mg/l for heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) and from 0.572 to 10.545 mg/l for organics (benzene, DMSO, DDE, endrin, dichloromethane, chlorobenzene, 1,2-dichlorobenzene and 1,3-dichlorobenzene). Water effluent samples were then tested. The FM22 gave different toxic reactions to them. Water samples were characterised for heavy metals. The FM22 bioassay had a higher sensitivity than the FM80 and a high reproducibility in the toxicity test with pure compounds. The FM22 test was a good predictor of toxicity for water samples; the bioassay is easy, low cost and rapid, then usable for routine tests

Interactions of melatonin with mammalian mitochondria. Reducer of energy capacity and amplifier of permeability transition.

Melatonin, a metabolic product of the amino acid tryptophan, induces a dose-dependent energy drop correlated with a decrease in the oxidative phosphorylation process in isolated rat liver mitochondria. This effect involves a gradual decrease in the respiratory control index and significant alterations in the state 4/state 3 transition of membrane potential (ΔΨ). Melatonin, alone, does not affect the insulating properties of the inner membrane but, in the presence of supraphysiological Ca2+, induces a ΔΨ drop and colloid-osmotic mitochondrial swelling. These events are sensitive to cyclosporin A and the inhibitors of Ca2+ transport, indicative of the induction or amplification of the mitochondrial permeability transition. This phenomenon is triggered by oxidative stress induced by melatonin and Ca2+, with the generation of hydrogen peroxide and the consequent oxidation of sulfydryl groups, glutathione and pyridine nucleotides. In addition, melatonin, again in the presence of Ca2+, can also induce substantial release of cytochrome C and AIF (apoptosis-inducing factor), thus revealing its potential as a pro-apoptotic agent

Effect of peroxides on spermine transport in rat brain and liver mitochondria.

The polyamine spermine is transported into the matrix of various types of mitochondria by a specific uniporter system identified as a protein channel. This mechanism is regulated by the membrane potential; other regulatory effectors are unknown. This study analyzes the transport of spermine in the presence of peroxides in both isolated rat liver and brain mitochondria, in order to evaluate the involvement of the redox state in this mechanism, and to compare its effect in both types of mitochondria. In liver mitochondria peroxides are able to inhibit spermine transport. This effect is indicative of redox regulation by the transporter, probably due to the presence of critical thiol groups along the transport pathway, or in close association with it, with different accessibility for the peroxides and performing different functions. In brain mitochondria, peroxides have several effects, supporting the hypothesis of a different regulation of spermine transport. The fact that peroxovanadate can inhibit tyrosine phosphatases in brain mitochondria suggests that mitochondrial spermine transport is regulated by tyrosine phosphorylation in this organ. In this regard, the evaluation of spermine transport in the presence of Src inhibitors suggests the involvement of Src family kinases in this process. It is possible that phosphorylation sites for Src kinases are present in the channel pathway and have an inhibitory effect on spermine transport under regulation by Src kinases. The results of this study suggest that the activity of the spermine transporter probably depends on the redox and/or tyrosine phosphorylation state of mitochondria, and that its regulation may be different in distinct organs

Defining Requirements for a BIM-Enabled Learning Environment

Digitalization is transforming the real estate and construction (REC) sector and a key feature of this transformation is Building Information Modelling (BIM). BIM offers opportunities for improving education and training through data-rich virtual environments in which project-based learning experiences can be designed and delivered. This could lead to considerable changes and improvements to the education and training of different professionals in the REC sector from managers to site workers. Researchers at Tallinn University of Technology, Tampere University, and the University of Bologna are currently developing a BIM-enabled Learning Environment (BLE) with the intention of providing more realistic, immersive, and integrated learning experiences. A desk study identifying existing initiatives, mapping the educational-technological systems in the partner universities, and analyzing existing BIM-enabled learning experiences at each partner university revealed an initial list of functional requirements for a BLE. This list was elaborated through 31 interviews of REC stakeholders in the three partner countries. A validation workshop was then held to confirm the relevance of the identified functional requirements, rank them in terms of their relative importance and identify any missing requirements. The resulting, validated functional requirements were then presented to technical experts at each of the universities for recommendations on how these functions could be technically delivered in the context of a BLE. Analysis of their feedback suggests a system design comprising a host platform based on a Learning Management System (LMS) installation with additional collaboration tools and further integrations with (open) BIM solutions to enable course-specific BIM functionalities. This research relates to Sustainable Development Goals (SDGs) 4-Quality Education, as the BLE is intended to enhance education and training possibilities in the REC sector and 11-Sustainable Cities and Communities, as the result of improved REC education and training will lead to a more sustainable Built Environment

A case history of low frequency air-borne sound produced by a weir in the river Reno

Marzabotto is a small village in the north of Italy, near the city of Bologna. The town lies at the bottom of a broad valley where the river Reno flows. In 1985 strange vibrations of glass windows and doors started to disturb the rest and sleep of the population. Local newspapers wrote about the awakening of the ghosts of ancient Etruscans, a population that lived in this area in olden times. In order to discover the source of such vibrations, the authorities of the village first called researchers of the National Institute of Geophysics who made measurements of vibration in different parts of the village and identified the waterfall of a weir, recently built to control the flow of the river Reno, as the source of the phenomena. The spectrum of the vibrations was characterized by a frequency of 8 Hz. The presence of such at distances of about 4 - respect to the valley floor, of the phenomena could be vibrations 5 Km and brought up by air as far in the well away from the weir, raised positions with idea that transmission as by ground. Local authorities decided to start new investigations and entrusted the work to the Institute of Technical Physics and the Institute of Hydraulics of the University of Bologna. It was decided to begin a campaign of systematic measurements of noise and vibration in order to understand the origin of the phenomena

An in vitro study on the toxic effects of nonylphenols (NP) in mitochondria

This paper is focused on alkylphenols, compounds which are formed by the biodegradation of polyethoxilatedalkylphenols detergents. Our experiments show that alkylphenols act not only as detergents, butalsoasuncouplersoftheoxidativephosphorylation. Thiseff~ot,canbeobservedatverylowdoses,thus suggesting that the preferential target ofnonylphenols in living organisms are mitochondria

Toksičnost talija u humanoj populaciji

Thallium is a naturally occurring trace element, widely distributed in the earth’s crust, but at very low concentrations. It does not have a known biological use and does not appear to be an essential element for life. It has been considered one of the most toxic heavy metals. Occasionally, there are reports on thallium poisoning as results of suicide or murder attempt or accident. The main threat to humans is through occupational exposure, environmental contamination, and accumulation in food, mainly in vegetables grown on contaminated soil. Increasing use in emerging new technologies and demanding high-tech industry constantly raise concern about exposure risk to all living organisms. Thallium is considered a cumulative poison that can cause adverse health effects and degenerative changes in many organs. The effects are the most severe in the nervous system. The exact mechanism of thallium toxicity still remains unknown, although impaired glutathione metabolism, oxidative stress, and disruption of potassium-regulated homeostasis may play a role. The lack of data about mutagenic, carcinogenic, or teratogenic effects of thallium compounds in humans calls for further research.Talij je u prirodi široko rasprostranjen teški metal, prisutan u vrlo niskim koncentracijama pa ga stoga ubrajamo u elemente u tragovima. Budući da organizmima nije potreban ni u jednoj razvojnoj fazi, ne ubrajamo ga u grupu esencijalnih elemenata. Talij zbog njegovih svojstava ubrajamo među najtoksičnije teške metale. Povremeno se još uvijek pojavljuju slučajevi u kojima je talij upotrijebljen kao sredstvo za pokušaj ubojstva, odnosno samoubojstva, ali i slučajevi nenamjernog, slučajnog trovanja talijem. U današnje vrijeme potencijalna o asnost od trovanja talijem postoji zbog profesionalne izloženosti, izbijanja ekološke katastrofe ili zbog akumulacije u hranidbenim lancima, uglavnom zbog uzgoja hrane na onečišćenom tlu. Sve češća uporaba talija u visokotehnološkoj industriji kao odgovor na zahtjeve moderne tehnologije neprestano povećava rizik od izloženosti svih živih organizama štetnim utjecajima talija u okolišu. Talij ima izuzetno negativan učinak na različite organske sustave, a osobito na živčani sustav. Mehanizmi toksičnosti talija još uvijek nisu u potpunosti razjašnjeni, premda važnu ulogu imaju poremećaji metabolizma glutationa, oksidativni stres i narušavanje homeostaze posredovane ionima kalija. Nedostatak podataka o mutagenim, kancerogenim ili teratogenim učincima talija i njegovih spojeva u ljudi opravdava buduća istraživanja ovog vrlo toksičnog metala

Determination of Chlorinated organic compounds in aqueous matrices

Thirteen pure volatile, semi-volatile and non-volatile chlorinated organic compounds of molecular weights ranging from trichloroethylene (MW = 131.39 g mole -¹) to hexachlorobenzene (MW = 284.78 g mole-¹) were determined in aqueous matrices by GC-ECD. After 10% salt addition, different extraction tests were performed using fibres whose adsorbing phase was based on microsphere carbon particles characterized by a constant size. Five experimental parameters were optimized: extraction temperature and time, position of the fibre in the GC injector port, desorption temperature and time. The optimized analytical protocol was employed to determine the efficiency of a real activated carbon adsorption plant to remove organic chlorinated pollutants from an industrial wastewater at ng l-¹ levels