Genetic and phenotypic variation of Fusarium proliferatum isolates from different host species

Fusarium proliferatum (Matsushima) Nirenberg is a common pathogen infecting numerous crop plants and occurring in various climatic zones. It produces large amounts of fumonisins, a group of polyketide-derived mycotoxins. Fumonisin biosynthesis is determined by the presence and activity of the FUM cluster, several co-regulated genes with a common expression pattern. In the present work, we analyzed 38 F. proliferatum isolates from different host plant species, demonstrating host-specific polymorphisms in partial sequences of the key FUM1 gene (encoding polyketide synthase). We also studied growth rates across different temperatures and sample origin and tried to establish the relationships between DNA sequence polymorphism and toxigenic potential. Phylogenetic analysis was conducted based on FUM1 and tef-1α sequences for all isolates. The results indicated the greatest variations of both toxigenic potential and growth patterns found across the wide selection of isolates derived from maize. Fumonisin production for maize isolates ranged from 3.74 to 4,500 μg/g of fumonisin B1. The most efficient producer isolates obtained from other host plants were only able to synthesize 1,820–2,419 μg/g of this metabolite. A weak negative rank correlation between fumonisin content and isolate growth rates was observed. All garlic-derived isolates formed a distinct group on a FUM1-based dendrogram. A second clade consisted of tropical and sub-tropical strains (isolated from pineapple and date palm). Interestingly, isolates with the fastest growth patterns were also grouped together and included both isolates originating from rice. The sequence of the FUM1 gene was found to be useful in revealing the intraspecific polymorphism, which is, to some extent, specifically correlated with the host plant

Rewolucja konsumentów? Ekonomia współdzielenia jako nowa wizja ładu społecznego

Uber, Airbnb, CouchSurfing, Netflix, electric scooters: all of these have become part of our daily lives, just as Allegro.pl, Amazon.com and other network economy businesses already have. Even so, according to their promoters they are a harbinger of a new order. For the market economy, with its anonymous market, sharing economy practices are to be what institutions of direct citizen influence on political decisions are to representative democracy. The economy will at last begin to fulfil actual human needs instead of producing superfluous things on a mass scale. The Earth’s devastation and the wasteful exploitation of its resources will cease. Old pre-capitalist economy institutions, spread all over the globe by means of the Internet, will empower the people marginalized by the market and reconstruct the communities weakened by it. Trust will be the greatest capital at people’s disposal, both in the local and global exchange of things and services. I do not estimate how realistic this promise is; all I do is present, from the perspectives of both sharing economy advocates and its critics, the specific institutions (in the sociological sense) meant to deliver on it. In the summing-up I highlight the ambivalence towards the market economy that the very idea of sharing itself is burdened with, and consequently, the ambiguity of its self-professed mission: is to be a mere correction to the present-day form of capitalism or an alternative to it?Uber, Airbnb, CouchSurfing, Netflix, elektryczne hulajnogi – te instytucje wrosły w nasze codzienne życie tak samo jak Allegro.pl, Amazon.com i inne przedsiębiorstwa gospodarki sieciowej. A jednak w opinii ich propagatorów są one zwiastunem nowego porządku. Dla gospodarki rynkowej z jej anonimowym rynkiem praktyki współdzielenia mają być tym, czy dla demokracji przedstawicielskiej instytucje bezpośredniego oddziaływania obywateli na decyzje polityczne. Gospodarka będzie wreszcie zaspokajać rzeczywiste ludzkie potrzeby, zamiast produkować na masową skalę rzeczy zbędne. Powstrzymana zostanie dewastacja Ziemi i rabunkowe korzystanie z jej zasobów. Instytucje przedkapitalistycznej gospodarki, za sprawą Internetu rozciągnięte na globalną skalę, przyniosą upodmiotowienie ludzi zmarginalizowanych przez rynek i odbudują osłabioną przez niego wspólnotę. Zaufanie będzie największym kapitałem, jakim ludzie będą dysponować tyleż w lokalnej, co globalnej wymianie rzeczy i usług. Nie będę oceniać, jakie szanse realizacji ma ta obietnica, przedstawię jedynie z perspektywy propagatorów współdzielenia, jak i jego krytyków, specyficzne instytucje (w sensie socjologicznym), które mają ją realizować. W podsumowaniu zwrócę uwagę na ambiwalencję wobec gospodarki rynkowej, jaką obarczona jest sama idea współdzielenia, a co za tym idzie, na dwuznaczność jej deklarowanej misji: czy ma być tylko korektą wobec obecnej formy kapitalizmu czy też jej alternatywą

Uloga pročišćavanja otpadnih voda u smanjenju onečišćenja površinskih voda zearalenonom

Zearalenone (ZEA) is a mycotoxin produced by some Fusarium species in food and feed. The toxicity of ZEA and its metabolites is related to the chemical structure of the mycotoxin, which is similar to naturally occurring oestrogens. Currently, there is increasing awareness of the presence of fungi and their toxic metabolites in the aquatic environment. One of the sources of these compounds are the effluents from wastewater treatment plants. The average annual efficiency of zearalenone reduction in the Łęczyca plant in our three-year study was in the range from 51.35 to 69.70 %. The three-way analysis of variance (year, month, and kind of wastewater) shows that the main effects of all factors and all interactions between them were significant for zearalenone and dissolved organic carbon content. Our findings suggest that wastewater is not the main source of surface water pollution with zearalenone. Future research should investigate the means to reduce ZEA and its migration from the fields through prevention strategies such as breeding for crops, plant debris management (crop rotation, tillage), and/or chemical and biological control.Zearalenon (ZEA) je mikotoksin koji u hrani proizvode neke vrste gljivica roda Fusarium. Njegova toksičnost i toksičnost njegovih metabolita ovisi o kemijskoj strukturi mikotoksina, a djelovanje mu je slično onome prirodnoga estrogena. Sve smo svjesniji važnosti gljivica i njihovih toksičnih metabolita u vodenom okolišu. Jedan od izvora spoja u površinskim vodama jesu i otpadne vode. Naše je trogodišnje praćenje pokazalo da se uspješnost pročišćenja zearalenona iz otpadnih voda kreće u rasponu od 51,35 do 69,70 % na godišnjoj razini. Trostrana analiza varijance (godina, mjesec, vrsta otpadne vode - nepročišćena/pročišćena) upućuje na to da je djelovanje svih čimbenika i svih njihovih međusobnih interakcija značajno utjecalo na razine zearalenona i otopljenog organskog ugljika. Istraživanje je pokazalo da otpadne vode nisu glavni izvor onečišćenja površinskih voda zearalenonom. Buduća bi istraživanja trebala utvrditi preventivne strategije uzgoja, upravljanja ostacima biljke (rotacijom, obradom zemljišta), odnosno tretiranje kemijskim i biološkim sredstvima kojima bi se smanjile razine zearalenona i njegova migracija s polja u vodeni okoliš

Novel KCNQ1 mutations in patients after myocardial infarction

Background: Patients after myocardial infarction (MI) are at greater risk of sudden cardiac death (SCD) than people in the overall population. The aim of this study was to detect mutations, including intronic ones, in the KCNQ1 gene coding for proteins of cardiac potassium channels and evaluate their possible effects on the clinical course in patients after MI. Methods: The study group was composed of 100 Polish patients after MI, which included 27 women (mean age 69 years) and 73 men (mean age 67 years). All patients underwent clinical examinations and genetic tests. The genetic test results have been correlated with the clinical data. The following parameters have been chosen as endpoints for this survey: sudden cardiac arrest (SCA) or SCD, complex ventricular arrhythmia, QT interval and QT dispersion values assessed during 24-hour Holter ECG monitoring in relation to ventricular arrhythmias as well as the minimum and maximum heart rate (HR) observed during the examination. Results: Six new mutations in the KCNQ1 gene: C2505734T, A2753831C in exons and C2505846A, G2753881A, T2755854C, T2755875G in introns. Detected intronic mutations in patients after MI were related to a worse clinical course and frequent occurrence of SCA. Conclusions: The novel intronic mutations may have a significant influence on the clinical course of the disease. (Cardiol J 2008; 15: 252-260

MIKOTOKSINI U HRANI, KRMNIM SMJESAMA I KRMIVIMA

Mycotoxins are toxic secondary metabolites formed by toxigenic fungi present in foods, feeds and their components. Since the presence of the above men¬tioned microorganisms is unavoidable, mold growth is an inevitable consequence of conditions advantageous for fungi development (water content and temperature) found in case of specific food and feed technologies. Mycotoxins identified up to now (several hundred) are molecules of different chemical structures and molecular weight up to 500 Da. An attempt to explain why biosynthesis of so many toxic metabolites – are the consequence of primary metabolism – is necessary for fungi will be discussed. Exposure of human beings and animals to the above compounds causes undesirable effects, with a broad variety of biological effects and – as a consequence – chronic diseases called mycotoxicoses. The most important genera of toxigenic and pathogenic fungi Aspergillus, Fusarium and Penicillium will be characterized, especially concerning conditions of rapid growth and development followed by biosynthesis of a variety of mycotoxins.The above microorganisms are related – during vegetation – to plant oxidative stress induced by weather and environment conditions. The above as well as biosynthesis of the metabolites will be discussed. Rapid development of fungi followed by toxin formation causes a reduction of crop yields, a deterioration of their quality and as a consequence results in significant economic losses, as worldwide approximately 25% of crops are affected by mycotoxins annually. Presented results will confirm that six metabolites (aflatoxins B1, ZEA, DON, fumonisins, T-2 toxin and OTA) in diverse materials (matrices) repre¬sent a real problem throughout the world. Occurrence and concentration levels are variable for different mycotoxins and are closely related to the weather conditions and plant stress responsible for the metabolite formation, which will be highlighted. Levels of safety will be discussed with the emphasis on low doses which cause subclinical losses. Most of the diseases occur after consumption of mycotoxin-contaminated grains or their products, but other routes of exposure also exist. The diagnosis of mycotoxicoses is dependent upon adequate testing for mycotoxins, involving sampling, sample preparation and analysis. Information on mycotoxin contamination of foods, feeds and their components as well as relevant data on new sources of contamination will be given. Methods of decontamination are usually difficult, so prevention of mycotoxin formation is of prime concern. Results on breeding of cereal varieties resistant to pathogenic fungi and biosynthesis of toxic secondary metabolites (mycotoxins) will be presented with an emphasis on the reduction of human and animal health risk. Recent results indicating the importance of mycotoxins in Poland (compared to world data) are planned to be discussed.Mikotoksini su toksični sekundarni metaboliti koje stvaraju toksigene gljivice što se nalaze u hrani, krmnim smjesama i krmivima. Budući da je postojanje ovih mikroorganizama neizbježivo, rast plijesni je neizbježna posljedica povoljnih uvjeta za razvoj gljivica (sadržaj vode i temperatura) u specifičnim tehnologijama hrane i krmiva. Dosad identificirani mikotoksini (nekoliko stotina) su molekule različitih kemijskih struktura i molekularne težine do 500 Da. U radu će se raspravljati o pokušaju objašnjenja zašto je za gljivice potrebna biosinteza tolikih toksičnih metabolita - kao posljedica primarnog metabolizma. Izlaganje ljudi i životinja navedenim komponentama uzrokuje nepoželjne učinke i mnogo različitih bioloških učinaka te kao posljedicu kronične bolesti zvane mikotoksikoze. Opisat će se najvažnije vrste toksigenih i patogenih gljivica Aspergillus, Fusarium i Penicillium, osobito uvjeti brzog rasta i razvoja te biosinteza raznih mikotoksina. Gore navedeni mikroorganizmi u vezi su za vrijeme vegetacije s oksidativnim stresom biljke izazvanim vremenskim i okolišnim uvjetima. Raspravljat će se o ovome, kao i o biosintezi metabolita. Brzi razvoj gljivica te stvaranje toksina uzrokuje smanjenje prinosa usjeva, pad njihove kvalitete, te kao posljedicu, znatne privredne gubitke budući da je širom svijeta godišnje oko 25% usjeva zahvaćeno mikotoksinima. Izneseni podaci će potvrditi da šest metabolita (aflatoksini, B1, ZEA, DON, fumonizini, toksin T-2 i OTA) u različitim materijalima (matricama) predstavljaju stvarni problem u čitavom svijetu. Pojava i razine koncentracije variraju za razne mikotoksine i usko su povezane s vremenskim uvjetima i stresom biljke, odgovornima za stvaranje metabolita. Govorit će se o razinama sigurnosti s težištem na niskim dozama, što uzrokuje subkliničke gubitke. Većina bolesti pojavljuje se nakon konzumiranja različitog zrnja ili njihovih proi zvoda zaraženih mikotoksinima, ali postoje i drugi načini izlaganja. Dijagnoziranje mikotoksikoza ovisi o odgovarajućem testiranju na mikotoksine uključujući uzorkovanje, pripremu uzoraka i analizu. Govorit će se o zaraženosti hrane, krmnih smjesa i krmiva mikotoksinima te dati i odgovarajući podaci o novim izvorima zaraze. Metode dekontaminacije su obično teške pa je sprječavanje stvaranja mikotoksina od prvenstvene važnosti. Bit će predstavljeni rezultati istraživanja niza žitarica otpornih na patogene gljivice i biosinteza toksičnih sekundarnih metabolita (mikotoksina) s naglaskom na smanjenje rizika za zdravlje ljudi i životinja. Predmet rasprave bit će najnoviji rezultati što upućuju na važnost mikotoksina u Poljskoj (u usporedbi s podacima u svijetu)

Corrosion resistance of heat-treated Ni-W alloy coatings

The paper presents research on evaluation of corrosion resistance of Ni-W alloy coatings subjected to heat treatment. The corrosion resistance was tested in 5% NaCl solution by the use of potentiodynamic polarization technique and electrochemical impedance spectroscopy. Characteristics of the Ni-W coatings after heat treatment were carried out using scanning electron microscopy, scanning Kelvin probe technique and X-ray di raction. Suggested reasons for the improvement of properties of the heat treated Ni-W coating, obtained at the lowest current density value (125 mA cm2), are the highest tungsten content (c.a. 25 at.%) as well as the smallest and the most homogeneous electrochemically active surface area

Novel organic material induced by electron beam irradiation for medical application

This study analyzed the e ects of irradiation of polytetrafluoroethylene (PTFE) containing 40% of bronze using an electron beam with energy of 10 MeV. Dosages from 26 to156 kGy (2.6–15.6 Mrad) were used. The impact of a high-energy electron beam on the thermal, spectrophotometric, mechanical, and tribological properties was determined, and the results were compared with those obtained for pure PTFE. Thermal properties studies showed that such irradiation caused changes in melting temperature Tm and crystallization temperature Tc, an increase in crystallization heat DHc, and a large increase in crystallinity c proportional to the absorbed dose for both polymers. The addition of bronze decreased the degree of crystallinity of PTFE by twofold. Infrared spectroscopy (FTIR) studies confirmed that the main phenomenon associated with electron beam irradiation was the photodegradation of the polymer chains for both PTFE containing bronze and pure PTFE. This had a direct e ect on the increase in the degree of crystallinity observed in DSC studies. The use of a bronze additive could lead to energy dissipation over the additive particles. An increase in hardness H and Young’s modulus E was also observed. The addition of bronze and the irradiation with an electron beam improved of the operational properties of PTFE