A new species of <Emphasis Type="Italic">Isospora</Emphasis> Schneider, 1881 (Apicomplexa: Eimeriidae) in Ruppell’s agama <Emphasis Type="Italic">Agama rueppelli</Emphasis> (Vaillant) (Sauria: Agamidae) from East Africa,with a review of this genus in agamid lizards

Coprological examinations of eight Ruppell’s agamas Agama rueppelli (Vaillant) revealed the presence of a coccidium of the genus Isospora Schneider, 1881 that represents a previously undescribed species. Oöcysts of Isospora farahi n. sp. are spherical or subspherical, 29.1 (26–31) × 28.8 (26–31) μm, with a shape-index of 1.01 (1–1.07). An oöcyst residuum, polar granules and micropyle are absent. The oöcyst wall is bilayered, brownish and smooth, c. 1.5–2 μm thick. The sporocysts are oval, 16.6 (15–18) × 11.4 (11–12) μm, with a shape-index of 1.46 (1.25–1.64) and both Stieda and substieda bodies. A sporocyst residuum is present as medium-sized granules scattered irregularly among the sporozoites. The sporozoites are vermiform, with a large posterior spherical refractile body. Endogenous development is intranuclear in the epithelial cells of the small intestine. Sporulation is unknown, as oöcysts were recovered from the faeces.     

Inhibition of glycerophosphate-dependent H2O2 generation in brown fat mitochondria by idebenone

The established protective effect of coenzyme Q (CoQ) analogs is dependent on the location of reactive oxygen species (ROS) generation. One of these analogs--idebenone (hydroxydecyl-ubiquinone) is used as an antioxidative therapeutic drug. We tested its scavenging effect on the glycerophosphate (GP)-dependent ROS production as this enzyme was shown as a new site in the mitochondrial respiratory chain where ROS can be generated. We observed that idebenone inhibits both GP- and succinate-dependent ROS production. Idebenone and CoQ1 were found to be more efficient in the scavenging activity (IC50: 0.052 and 0.075 microM, respectively) than CoQ3 (IC50: 45.8 microM). Idebenone also inhibited ferricyanide (FeCN)-activated, GP-dependent ROS production. Our data thus extend previous findings on the scavenging effect of idebenone and show that it can also eliminate GP-dependent ROS generation.     

Epidemiology of Helicobacter pylori infection in the Czech Republic

BACKGROUND: Prevalence of Helicobacter pylori infection has been estimated to range from 60 to 95% in the former communist countries of Central and Eastern Europe. The aim of this study was to evaluate H. pylori infection prevalence in a representative sample of the Czech population. The second objective was to describe difference of H. pylori prevalence between different social groups of children and adults. MATERIALS AND METHODS: A total of 2509 persons aged 5-100 years, randomly selected out of 30,012 persons of the general population, took part in the study. H. pylori infection was investigated by means of 13C-urea breath test. Breath samples were analyzed by isotope ratio mass spectrometry. Social and demographic characteristics were based on data from self-completed questionnaires. RESULTS: Using the total Czech population as a standard, we estimated the age-standardized prevalence of H. pylori in males aged 5+ years at 41.9% (95% CI 39.0%, 44.8%) and in females aged 5+ years at 41.4% (95% CI 38.6%, 44.3%) in 2001. Prevalence of H. pylori increased with age but was not related to gender. Children of mothers with basic or lower education, living in crowded accommodations, without access to running warm water, and residing in smaller towns appear to be at the highest risk. Low education and heavy smoking are most strongly associated with prevalence of H. pylori positivity in adults and adolescents. CONCLUSIONS: This is a unique study based on a representative sample of the general population in a Central European country. The overall prevalence of H. pylori is lower than previously assumed and could partly reflect a substantial recent decrease in H. pylori prevalence in the Czech Republic. Consistent with earlier studies, H. pylori infection is strongly influenced by socioeconomic conditions and childhood poverty.     

Possible metabolic pathways of conversion of formaldoxime and glyceryl trinitrate to NO

The oxidation of N-hydroxylated compounds may result in production of nitrogen oxides, including nitric oxide (NO). Oxidation may be independent on NO-synthase. Production of nitrites and nitrates via NO from formaldoxime and glyceryl trinitrate was studied and compared. Superoxide ion, ions Fe2+ and Fe3+, methemoglobin and methemoglobin + NADPH + methylene blue, oxyhemoglobin and oxyhemoglobin + NADPH + methylene blue in the presence of atmospheric oxygen were used as oxidoreductive agents. Formaldoxime (triformaxime) was chosen as a newly recognized atypical cyclic oxime which can be converted to NO and glyceryl trinitrate as a well-known NO donor of quite different structure. From the oxidoreductive agents used, glyceryl trinitrate was not converted to nitrites or nitrates by Fe2+ or Fe3+ and by methemoglobin alone. Formaldoxime was resistant to the action of superoxide ion and methemoglobin alone. Importance of these possible metabolic pathways for production of NO from examined vasodilators is discussed.     

Changes in intervertebral disc morphology persist 5 mo after 21-day bed rest

As part of the nutrition-countermeasures (NUC) study in Cologne, Germany in 2010, seven healthy male subjects underwent 21 days of head-down tilt bed rest and returned 153 days later to undergo a second bout of 21-day bed rest. As part of this model, we aimed to examine the recovery of the lumbar intervertebral discs and muscle cross-sectional area (CSA) after bed rest using magnetic resonance imaging and conduct a pilot study on the effects of bed rest in lumbar muscle activation, as measured by signal intensity changes in T(2)-weighted images after a standardized isometric spinal extension loading task. The changes in intervertebral disc volume, anterior and posterior disc height, and intervertebral length seen after bed rest did not return to prebed-rest values 153 days later. While recovery of muscle CSA occurred after bed rest, increases (P ≤ 0.016) in multifidus, psoas, and quadratus lumborum muscle CSA were seen 153 days after bed rest. A trend was seen for greater activation of the erector spinae and multifidus muscles in the standardized loading task after bed rest. Greater reductions of multifidus and psoas CSA muscle and greater increases in multifidus signal intensity with loading were associated with incidence of low back pain in the first 28 days after bed rest (P ≤ 0.044). The current study contributes to our understanding of the recovery of the lumbar spine after 21-day bed rest, and the main finding was that a decrease in spinal extensor muscle CSA recovers within 5 mo after bed rest but that changes in the intervertebral discs persist.     

Influence of 2,4-d and lactose on pollen embryogenesis in anther culture of potato

Anthers of diploid genotypes of Solanum tuberosum capable of androgenesis were cultured on different media to examine the effect on induction of pollen embryogenesis of 2,4-d and lactose. Anthers cultured in callogenic medium with 2,4-d and sucrose produced pollen derived embryoids only exceptionally. When sucrose was replaced by lactose the frequency of embryogenesis was as high or higher than in embryogenic auxin-free medium. Substitution of lactose for sucrose in the embryogenic medium had no effect. Supplementing the embryogenic medium with 2,4-d strongly reduced the frequency of pollen embryoids in the presence of sucrose but not with lactose.Abbreviations 2,4-d 2,4-dichlorophenoxyacetic acid     

Cloning and characterization of the pknA gene from Streptomyces coelicolor A3(2), coding for the Mn2+ dependent protein Ser/Thr kinase

A gene pknA, coding for an eukaryotic-type protein Ser/Thr kinase, was cloned from the Streptomyces coelicolor A3(2) chromosome. The PknA protein kinase, containing the C-terminal eukaryotic-type kinase domain with an N-terminal extension, was expressed in Escherichia coli and Streptomyces lividans. The affinity purified MBP-PknA fusion protein was assayed for kinase activity that showed its ability to autophosphorylate in vitro in the presence of [gamma-32P]ATP. The activity was Mn2+ dependent. The preautophosphorylated kinase phosphorylated at least two proteins (sizes 30 and 32 kDa) in the S. coelicolor J1501 cell-free extracts of all developmental stages. The larger of them was also phosphorylated in vitro by an endogenous protein kinase in late stages extracts, but not earlier. Although Mn2+ dependent protein phosphorylation has previously been described in Streptomyces, this is the first report of a gene encoding such an enzyme in this genus.     

Studien über die Funktion der im Wasser gelösten Nährsubstanzen im Stoffwechsel der Wassertiere

Ohne Zusammenfassung     

Simulation of intrafollicular conditions prevents GVBD in bovine oocytes: a better alternative to affect their developmental capacity after two-step culture

To increase the developmental competence of bovine oocytes isolated from small, medium, and large follicles (2-3, 3-4, and 4-6 mm in diameter, respectively), we tried to modify the conditions for their in vitro culture. The first step involved conditions maintaining at least for 48 hr a reversible inhibition of the germinal vesicle breakdown (GVBD) and the second step stimulated the resumption of meiosis and completion of nuclear and cytoplasmic maturation during the subsequent 20-22 hr of culture. The effectiveness of this model depended mainly on the medium composition (reduced NaHCO3, substitution of serum with serum albumin, addition of antioxidants (curcumin), increased viscosity by agar, the reduction of oxygen concentration (within 6%-8%), the reduction of the proportion between the number of cumulus-oocyte complexes (COCs), and the reduction of the amount of a medium (within 6-7 mul per COC) to amplify the GVBD-inhibitory effect of oocyte surrounding granulosa cells. The COCs were incubated in clumps of 6-7 COCs. The effectiveness and reversibility of GVBD inhibition depended also on the duration of COCs isolation. The full reversibility of the GV block was controlled morphologically and also by measuring histone H1 and MAP kinase activities. The two-step versus one-step (24 hr) maturation technique was evaluated by the percentage of total and hatched blastocysts at day 9. When compared with one-step maturation, the two-step culture showed a slightly increased proportion of total and hatched blastocysts developed from growing follicles, mainly from the smallest category (13.9% vs. 7.1% and 9.2% vs. 3.3% for total blastocysts and hatched, respectively). However, the two-step culture of oocytes from large regressing follicles substantially reduced the blastocyst yield (9.7% vs. 39.1% and 4.9% vs. 26.7% for total blastocysts and hatched, respectively). The transfer of ten blastocysts (developed after two-step culture) to ten recipients resulted in seven pregnancies.     

Die Mikrophotographie mit infraroten Strahlen im Dienste der Zellforschung

Ohne Zusammenfassung