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TOSHIHIRO TOKIWA DAVID MODRÝ AKIRA ITO KATEŘINA POMAJBÍKOVÁ KLÁRA J. PETRŽELKOVÁ SOICHI IMAI 《The Journal of eukaryotic microbiology》2010,57(2):115-120
ABSTRACT. Troglocorys cava n. g., n. sp. is described from the feces of wild eastern chimpanzee, Pan troglodytes schweinfurthii, in Uganda. This new species has a spherical body with a frontal lobe, a long vestibulum, a cytoproct located at the posterior dorsal side of the body, an ovoid macronucleus, a contractile vacuole near the cytoproct, and a large concavity on the left surface of the body. Buccal ciliature is non‐retractable and consists of three ciliary zones: an adoral zone surrounding the vestibular opening, a dorso‐adoral zone extending transversely at the basis of the frontal lobe, and a vestibular zone longitudinally extending in a gently spiral curve to line the surface of the vestibulum. Two non‐retractable somatic ciliary zones comprise arches over the body surface: a short dorsal ciliary arch extending transversely at the basis of the frontal lobe and a wide C‐shaped left ciliary arch in the left concavity. Because of the presence of three ciliary zones in the non‐retractable buccal ciliature, the present genus might be a member of the family Blepharocorythidae, but the large left concavity and the C‐shaped left ciliary arch are unique, such structures have never been described from other blepharocorythids. 相似文献
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The production of reactive oxygen species by dietary flavonols 总被引:1,自引:0,他引:1
Flavonols are a group of naturally occurring compounds which are widely distributed in nature where they are found glycosylated primarily in vegetables and fruits. A number of studies have found both anti- and prooxidant effects for many of these compounds. The most widely studied because of their ubiquitous nature have been quercetin, a B-dihydroxylated and myricetin, a B-trihydroxylated flavonol. Some of their prooxidant properties have been attributed to the fact that they can undergo autooxidation when dissolved in aqueous buffer. Studying a number of factors affecting autooxidation, we found the rate of autooxidation for both quercetin and myricetin to be highly pH dependent with no autooxidation detected for quercetin at physiologic pH. Both the addition of iron for the two flavonols and the addition of iron followed by SOD for quercetin at physiologic pH. Both the addistantially. Neither kaempferol, a monohydroxylated flavonol nor rutin, a glycosylated quercetin showed any ability to autooxidize. The results with rutin differ from what we expected based on the B-ring structural similarity to quercetin. The autooxidation of quercetin and myricetin was further studied by electron spin resonance spectroscopy (ESR). Whereas quercetin produced a characteristic DMPO-OH radical, it was not detected below a pH of 9. However, the addition of iron allowed the signal to be detected at a pH as low as 8.0. On the other hand, myricetin autooxidation yielded a semiquinone signal which upon the addition of iron, converted to a DMPO-OH signal detected at a pH of 7.5. In a microsome-NADPH system, quercetin produced an increase in oxygen utilization and with ESR, an ethanol-derived radical signal which could be completely suppressed by catalase indicating the dependence of the signal on hydrogen peroxide. These studies demonstrate that the extracellular production of active oxygen species by dietary flavonols is not likely to occur in vivo but the potential for intracellular redox cycling may have toxicologic significance. 相似文献
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The worldwide increase in the use of antibiotics as an integral part of poultry and livestock production industry has recently received increasing attention as a contributory factor in the international emergence of antibiotic-resistant bacteria in human beings. To gauge the presence of the aforementioned scenario in the Indian context, a preliminary survey was conducted to assess the use of chlortetracycline (CTC) in 12 commercial layer farms and to quantify and confirm its residue in the egg. Samples of feed and eggs were collected at day 0 (prior to CTC addition), 3rd, 5th and 7th day during treatment and on the 9th and 14th day (2nd and 7th day after withdrawal of CTC) from each of the 12 commercial poultry farms studied. Concentration of CTC in feed was significantly (P<0.01) high on the 3rd, 5th and 7th day. On the 9th day and 14th day CTC concentration in feed was significantly (P<0.01) lower compared to the earlier 3 days studied. A highly significant difference (P<0.01) of the antibiotic residue in egg was observed in all the 5 days with high residual levels of CTC in egg. CTC in feed and its residue in egg were detected even on the 9th and 14th day respectively. 相似文献
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KLARA BJÖRG JAKOBSDÓTTIR þÓRA DÖGG JÖRUNDSDÓTTIR SIGURLAUG SKÍRNISDÓTTIR SIGRÍÐUR HJÖRLEIFSDÓTTIR GUÐMUNDUR Ó. HREGGVIÐSSON ANNA KRISTÍN DANÍELSDÓTTIR CHRISTOPHE PAMPOULIE 《Molecular ecology resources》2006,6(2):337-339
Nine out of 22 microsatellite primers tested were successfully amplified on three samples of cod Gadus morhua L. (two contemporary and one archived otolith samples). All loci were polymorphic (5–23 alleles/locus). The average observed heterozygosity across loci and samples was 0.625, ranging from 0.294 to 0.895 at each locus. All loci were under Hardy–Weinberg equilibrium, except PGmo56 that showed significant excess of heterozygotes in all studied samples. The isolated loci were suitable for degraded DNA and therefore useful for conducting a long‐term temporal study with DNA obtained from archived otoliths of cod. 相似文献
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Abstract 1. Body size in parasitic insects can be subjected to contrasting selective pressures, especially if they complete their development within a single host. On the one hand, a larger body size is associated with a higher fitness. On the other hand, the host offers a discrete amount of resources, thus constraining the evolution of a disproportionate body size. 2. The present study used the weevil Curculio elephas as a study model. Larvae develop within a single acorn, feeding on its cotyledons, and larval body size is strongly related to individual fitness. 3. The relationship between larval and acorn size was negatively exponential. Larval growth was constrained in small acorns, which did not provide enough food for the weevils to attain their potential size. Larval size increased and levelled off in acorns over a certain size (inflexion point), in which cotyledons were rarely depleted. When there were more than one larva per acorn, a larger acorn was necessary to avoid food depletion. 4. The results show that C. elephas larvae are sometimes endoparasitic, living on the edge of host holding capacity. If they were smaller they could avoid food depletion more easily, but the fitness benefits linked to a larger size have probably promoted body size increase. The strong negative effects of conspecific competition may have possibly influenced female strategy of laying a single egg per seed. 5. Being larger and fitter, but always within the limits of the available host sizes, may be one main evolutionary dilemma in endoparasites. 相似文献
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Natália H Mendes Fernando AF Melo Adolfo CB Santos José RC Pandolfi Elisabete A Almeida Rosilene F Cardoso Henri Berghs Suzana David Faber K Johansen Lívia G Espanha Sergio RA Leite Clarice QF Leite 《BMC research notes》2011,4(1):269