Stimulated recovery of perturbed haematopoiesis by inhibition of prostaglandin production — promising therapeutic strategy

Inhibitors of prostaglandin production, designated as classical non-steroidal anti-inflammatory drugs (NSAIDs) and acting on the base of non-selective inhibition of cyclooxygenases, have been found in numerous studies to potentiate recovery of perturbed haematopoiesis by removing the negative feedback control mediated by prostaglandins. However, classical NSAIDs show pronounced undesirable gastrointestinal side effects, which limits the possibility of their utilization for various pathophysiological states including myelosuppression. Specific cyclooxygenase-2 (COX-2) inhibitors, targeted at selective inhibition of this inducible cyclooxygenase isoform and having much better gastrointestinal side effect profile, have been found in recent studies to retain the haematopoiesis-stimulating effects of classical NSAIDs. These results suggest that the indication spectrum of selective COX-2 inhibitors may be extended to the indication of myelosuppression of various etiology. Combining the anti-tumour and haematopoiesis-stimulating activities in a single COX-2 inhibitor may have a positive clinical impact.     

Ecology of <Emphasis Type="Italic">Leuctra geniculata</Emphasis> (Plecoptera: Leuctridae), an atlantomediterranean species on the north-eastern border of its area

The first records of Leuctra geniculata Stephens, 1836 in the north-eastern border of its area (the Czech Republic) are presented and an overview of references, synonyms and distribution of the species is given. The ecological preferences of the species, supported by chemical and hydromorphological parameters, are defined. Probable dissemination paths into the Czech Republic and the supposed life cycle of the species are discussed. Photographs of morphological characters, SEM photos of eggs, associated macroinvertebrate assemblages (EPT taxa) and maps of distribution are included.     

Life at elevated CO2 modifies the cell composition of Chromera velia (Chromerida)

We investigated the response to high CO₂ of Chromera velia, a photosynthetic relative of apicomplexan parasites that is possibly involved in symbiotic associations with scleractinian corals. The inorganic C content in the proximity of the symbiotic algal cells within the tissues of scleractinians is disputed. According to some authors, it is very high. A higher C content in the endodermal tissues of scleractinians than in the external environment may have favoured the constitution of symbiosis with organisms such as Symbiodinium and Chromera that have a type II Rubisco, which is intrinsically ill suited to low CO₂ environments. We thus cultured C. velia at the very high inorganic C estimated by some authors and assessed its growth and photosynthetic performance. We also evaluated whether these conditions affected C allocation and elemental stoichiometry in C. velia cells by state-of-the-art Fourier transform infrared spectroscopy and total reflection X-ray fluorescence spectrometry in combination with more traditional biochemical and physiological techniques. Our results demonstrated that C. velia was capable of coping with very high CO₂, which even stimulated biomass production and increased N, P, Mn, Fe and Zn use efficiency. Growth at elevated CO₂ changed the stoichiometric relationships among elements in C. velia cells, but had no effect on the relative abundance of the main organic pools. The high CO₂ in the animal tissue surrounding the photosynthetic cells may therefore facilitate C. velia life in symbiosis.     

Rechargeable Iron–Sulfur Battery without Polysulfide Shuttling

Sulfur represents one of the most promising cathode materials for next‐generation batteries; however, the widely observed polysulfide dissolution/shuttling phenomenon in metal–sulfur redox chemistries has severely restricted their applications. Here it is demonstrated that when pairing the sulfur electrode with the iron metal anode, the inherent insolubility of iron sulfides renders the shuttling‐free nature of the Fe–S electrochemical reactions. Consequently, the sulfur electrode exhibits promising performance for Fe²⁺ storage, where a high capacity of ≈1050 mAh g^?1, low polarization of ≈0.16 V as well as stable cycling of 150 cycles are realized. The Fe–S redox mechanism is further revealed as an intriguing stepwise conversion of S₈ ? FeS₂ ? Fe₃S₄ ? FeS, where a low volume expansion of ≈32.6% and all‐solid‐state phase transitions facilitate the reaction reversibility. This study suggests an alternative direction to exploit sulfur electrodes in rechargeable transition metal–sulfur batteries.     

Photosystem I trimers from Synechocystis PCC 6803 lacking the PsaF and PsaJ subunits bind an IsiA ring of 17 units

We report a structural characterization by electron microscopy and image analysis of a supramolecular complex consisting of Photosystem I (PSI) and the chlorophyll-binding protein IsiA from a mutant of the cyanobacterium Synechocystis PCC 6803 lacking the PsaF and PsaJ subunits. The circular complex consists of a central PSI trimer surrounded by a ring of 17 IsiA units, one less than in the wild-type supercomplex. We conclude that PsaF and PsaJ are not obligatory for the binding of the IsiA ring, and that the size of the PSI complex determines the number of IsiA units in the ring. The resulting number of 17 copies implies that each PSI monomer has a different association to the IsiA ring.     

Growth pattern of all‐female perch (Perca fluviatilis L.) juveniles – is monosex perch culture beneficial?

The study objective was to evaluate the enhanced profitability of monosex all-female stock (MS) culture compared to bisexual stock (BS) of Eurasian perch ( Perca fluviatilis L.) under intensive conditions. Monosex all-female stock was produced by mating masculinized females (neomales) with common females of a local strain; the bisexual stock was obtained from a local strain perch broodstock. Preceded by pond-nursing (60 days) and habituating (14 days) periods, the experiment lasted 126 days. Perch were held in six 50-L aquaria connected to a recirculation system, with each group tested in triplicate. No significant differences (P = 0.07) in total survival were observed between all-female and bisexual stock after 126 days of rearing, but MS gained 20% more (P = 0.04) in total body weight (final weight 25.2 ± 9.7 g; mean ± SD) than BS fish (21.0 ± 7.5 g). It is suggested that the culture of monosex female perch might therefore be of significant economic benefit. Overall feed conversion ratio for tanks with BS (1.43 ± 0.21) was significantly (P = 0.02) higher than in tanks with MS (1.30 ± 0.11) perch.