Влияние брассиностероидов на развитие мицелия базидиального гриба Pleurotus ostreatusв

Experiments on the effect of brassinosteroids and their salicylates on the mycelium biomass during submerged cultivation of oyster mushroom (Pleurotus ostreatus) were carried out. It was shown that their addition to the nutrient medium at a concentration of 0.05 mg/l significantly increases the biomass of the mycelium. It was found that, when exposed to 24- epi- and 28-homocastasterone for 9 days, the mycelium colony developed only in the depths of the culture liquid, and the mycelium was formed into glomeruli with a dense structure. The use of salicylates 24-epicastasterone and 6-deoxo-24-epicastasterone promoted the development of an extensive colony of mycelium both on the surface and in the depth of the culture liquid. Salicylates also influenced the structure of the mycelium – the jellyfish-like loose mycelium was observed in flasks with a medium containing 24-epi and 6-deoxo-24-epicastasterone salicylates. For the first time, the determination of the content of endogenous brassinosteroids in the fruiting body and mycelium of P. ostreatus was carried out.Проведенные эксперименты при погруженном культивировании вешенки обыкновенной (Pleurotus ostreatus) показали, что добавление в питательную среду брассиностероидов и их производных в концентрации 0,05 мг/л значительно увеличивает биомассу мицелия. Установлено, что при использовании 24-эпи- и 28-гомокастастерона при выращивании вешенки в течение 9 суток колония мицелия развивалась только в глубине культуральной жидкости, а мицелий формировался в клубочки с плотной структурой. Добавление салицилатов 24-эпикастастерона и 6-дезоксо-24-эпикастастерона способствовало развитию обширной колонии мицелия как на поверхности, так и в глубине культуральной жидкости. Салицилаты оказывали влияние и на структуру мицелия – медузоподобный рыхлый мицелий наблюдали в колбах со средой, содержащей салицилаты 24-эпи- и 6-дезоксо-24-эпикастастерона. В работе впервые установлено наличие и проведено количественное определение содержания эндогенных брассиностероидов ряда брассинолида, 24-эпибрассинолида и 28-гомобрассинолида в плодовом теле и мицелии гриба вешенки обыкновенной

Myocardial ketone body utilization in patients with heart failure. the impact of oral ketone ester

Aims: Upregulation of ketone body (β-hydroxybutyrate, βHB) utilization has been documented in human end-stage heart failure (HF), but is unclear if this is due to intrinsic cardiac metabolic remodeling or a HF-related catabolic state. This study sought to evaluate the maximal ketone body utilization capacity and its determinants in controls and in patients with moderate HF and reduced ejection fraction (HFrEF). Methods and results: 19 HFrEF patients and 9 controls underwent sampling from the arterial circulation (A) and coronary sinus (CS) to measure transmyocardial extraction of energy-providing substrates and oxygen. In a separate experiment, measurements were performed 80-min after oral administration of 25 g of ketone ester (KE, (R)-3-hydroxybutyl(R)-3-hydroxybutyrate) drink in 11 HFrEF and 6 control subjects. There were no statistically significant differences in fasting substrate levels and fractional extractions between HF and controls. Administration of KE increased βHB by 12.9-fold, revealing an increased ability to utilize ketones in HFrEF as compared to controls (fractional extraction, FE%: 52 vs 39%, p = 0.035). βHB FE% correlated directly with βHB myocardial delivery (r = 0.90), LV mass (r = 0.56), LV diameter (r = 0.65) and inversely with LV EF (−0.59) (all p < 0.05). βHB FE% positively correlated with lactate FE% (p < 0.01), but not with FFA or glucose FE%, arguing against substrate competition. Conclusions: Acute nutritional ketosis enhances βHB extraction in patients with HFrEF compared to controls, and this enhancement correlates with degree of cardiac dysfunction and remodeling. Data suggest that subclinical metabolic remodeling occurs early in HF progression. Further studies are needed to determine whether exogenous ketones may have a potential therapeutic role

NBN 657del5 heterozygous mutations and colorectal cancer risk in the Czech Republic

The most frequent Nijmegen breakage syndrome (NBS)-causing mutation is a 5-base pair deletion in gene coding for nibrin (NBN 657del5), which results in a non-fully functional protein product and is particularly frequent in Central and Eastern Europe. Recent studies have investigated whether NBN 657del5 carriage may predispose to an increased risk of different types of cancer. The Czech Republic has one of the highest incidences of colorectal cancer in the world as well as high incidence of NBS. To assess whether NBN 657del5 associates with an increased risk of sporadic colorectal cancer, we have screened 771 colorectal cancer patients, 614 controls with negative colonoscopy and 818 healthy blood donors from the Czech Republic. There were no significant differences between the frequencies of heterozygous carriers among the three groups. The present results do not provide any evidence that the exceeding risk of CRC in this population is attributable to the high frequency of heterozygous carriage of the NBN 657del5

Lake macroinvertebrates and the altitudinal environmental gradient in the Pyrenees

14 páginas, 6 tablas, 2 figuras.The distribution of different macroinvertebrate groups inhabiting the littoral zone of 82 mountain lakes in the Pyrenees was investigated in relation to the altitudinal environmental gradient. For each lake, altitude, longitude and latitude, together with 28 environmental variables, relating to chemical and physical characteristics and to lake general productivity, were considered. Using Principal Component Analysis (PCA) we showed that the altitudinal environmental gradient (i.e. altitude and altituderelated variables) represented the largest gradient of environmental variability. We found that incidence was related to altitude in about 50% of macroinvertebrate groups, most relationships being inverse, and also that the number of macroinvertebrate groups found per lake was better described by a second-order polynomial function than by simple linear regression. However, this relationship was linear for a subset of high-altitude lakes above 2,500 m a.s.l., suggesting an ecological threshold around this altitude. Redundancy Analyses (RDAs) showed the importance of environmental factors varying with altitude for the distribution of macroinvertebrate groups. Organic matter, salmonid presence, fine substrate dominance, macrophyte coverage, temperature and altitude by itself were, in this order, the most relevant factors. Partial RDAs showed that different combinations of these variables contributed to the explanation of the distribution of each group. However, the variable that uniquely explained most variability differed from group to group. We conclude that the altitudinal gradient is a multi-faceted ecological factor, which impinges on each group by means of some specific environmental variable(s) that are particularly relevant for the life history of that group.The field work of this study was financed by grants from the Academy of Finland to J. Heino and T. Muotka.Peer reviewe