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21.
Egbert Strauß Andreas Grauer Martina Bartel Roland Klein Ludger Wenzelides Grit Greiser Alexander Muchin Heike Nösel Armin Winter 《European Journal of Wildlife Research》2008,54(1):142-147
The German Wildlife Information System, founded in 2001, is a long-term monitoring program documenting occurrence, number,
and development of game populations throughout Germany. Population numbers are recorded by standardized counting methods in
so-called reference areas. The population densities of the European hare are calculated by spotlight strip censuses in the
reference areas each spring and autumn all across Germany. From 2002 to 2005, the censuses were carried out by local hunters
in 510 to 676 reference areas each year. During these years, the calculated spring densities increased significantly from
11.0 (2002) to 14.5 hares/km2 (2005) nationwide. The overall increase in spring densities was primarily caused by the population rise from spring 2003
to 2004, which correlates with the high net growth rate in 2003. In 2005, the number of counted hares varied between less
than 1 and more than 107 hares/km2 in spring and between 0 and more than 170 hares/km2 in autumn. Because of differing landscapes in Germany, three regions were differentiated. In spring 2005, the average population
densities (median) in East Germany (5.4 hares/km2) and Southwest Germany (14.6 hares/km2) were significantly lower than in Northwest Germany (23.9 hares/km2). These regional differences had been similarly distinct in former years. 相似文献
22.
Heike St?cklein Grit Hutter J?rg Kalla Elena Hartmann Yvonne Zimmermann Tiemo Katzenberger Patrick Adam Ellen Leich Sylvia H?ller Hans Konrad Müller-Hermelink Andreas Rosenwald German Ott Martin Dreyling 《Journal of Hematopathology》2008,1(2):85-95
Mantle cell lymphomas (MCL), characterized by the t(11;14)(q13;q32), frequently carry secondary genetic alterations such as deletions in chromosome 17p involving the TP53 locus. Given that the association between TP53-deletions and concurrent mutations of the remaining allele is weak and based on our recent report that the Hypermethylated in Cancer 1 (HIC1) gene, that is located telomeric to the TP53 gene, may be targeted by deletions in 17p in diffuse large B-cell lymphoma (DLBCL), we investigated whether HIC1 inactivations might also occur in MCL. Monoallelic deletions of the TP53 locus were detected in 18 out of 59 MCL (31%), while overexpression of p53 protein occurred in only 8 out of 18 of these MCL (44%). In TP53-deleted MCL, the HIC1 gene locus was co-deleted in 11 out of 18 cases (61%). However, neither TP53 nor HIC1 deletions did affect survival of MCL patients. In most analyzed cases, no hypermethylation of the HIC1 exon 1A promoter was observed (17 out of 20, 85%). However, in MCL cell lines without HIC1-hypermethylation, the mRNA expression levels of HIC1 were nevertheless significantly reduced, when compared to reactive lymph node specimens, pointing to the occurrence of mechanisms other than epigenetic or genetic events for the inactivation of HIC1 in this entity. 相似文献
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24.
NAD(P)-Dependent Aldehyde Dehydrogenases Induced during Growth of Ralstonia eutropha Strain Bo on Tetrahydrofurfuryl Alcohol 下载免费PDF全文
Different aldehyde dehydrogenases (AlDHs) were formed during growth of Ralstonia eutropha Bo on tetrahydrofurfuryl alcohol (THFA). One of these enzymes, AlDH 4, was purified and characterized as a homodimer containing no prosthetic groups, showing a strong substrate inhibition, and having an N-terminal sequence similar to those of various NAD(P)-dependent AlDHs. The conversion rate of THFA by the quinohemoprotein THFA dehydrogenase was increased by AlDH 4. 相似文献
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26.
Dealing with food shortage: larval dispersal behaviour and survival on non‐prey food of the hoverfly Episyrphus balteatus 下载免费PDF全文
1. Predatory larvae often have to face food shortages during their development, and thus the ability to disperse and find new feeding sites is crucial for survival. However, the dispersal capacity of predatory larvae, the host finding cues employed, and their use of alternative food sources are largely unknown. These aspects of the foraging behaviour of the aphidophagous hoverfly (Episyrphus balteatus De Geer) larvae were investigated in the present study. 2. It was shown that these hoverfly larvae do not leave a plant as long as there are aphids available, but that dispersing larvae are able to find other aphid colonies in the field. Dispersing hoverfly larvae accumulated on large aphid colonies, but did not distinguish between different pea aphid race–plant species combinations. Large aphid colonies might be easier to detect because of intensified searching by hoverfly larvae following the encounter of aphid cues like honeydew that accumulate around large colonies. 3. It was further shown that non‐prey food, such as diluted honey or pollen, was insufficient for hoverfly larvae to gain weight, but prolonged the survival of the larvae compared with unfed individuals. As soon as larvae were switched back to an aphid diet, they rapidly gained weight and some pupated after a few days. Although pupation and adult hatching rates were strongly reduced compared with hoverflies continuously fed with aphids, the consumption of non‐prey food most probably increases the probability that hoverfly larvae find an aphid colony and complete their development. 相似文献
27.
Marmoset phylogenetics, conservation perspectives, and evolution of the mtDNA control region 总被引:3,自引:1,他引:2
Tagliaro CH; Schneider MP; Schneider H; Sampaio IC; Stanhope MJ 《Molecular biology and evolution》1997,14(6):674-684
Marmosets (genus Callithrix) are a diverse group of platyrrhine primates
with 13-15 purported taxa, many of them considered endangered.
Morphological analyses constitute most of the basis for recognition of
these forms as distinct taxa. The purpose of this study was to provide a
molecular view, based on mitochondrial control region sequences, of the
evolutionary history of the marmosets, concomitant with a molecular
phylogenetic perspective on species diversity within the group. An
additional purpose was to provide the first comparative examination of a
complete New World monkey control region sequence with those of other
mammals. The phylogenetic analyses provide convincing support for a split
between the Atlantic forest and Amazonian marmosets, with the inclusion of
the pygmy marmoset (Cebuella pygmaea) at the base of the Amazonian clade.
The earliest branch of the Atlantic forest group was C. aurita. In the
Amazonian group, the analyses do not support the recognition of C.
humeralifer and the recently described C mauesi as distinct taxa. They do,
however, support a clear distinction between C. argentata and a strongly
supported mixed clade of C. humeralifer and C. mauesi. In the Atlantic
forest group, the phylogenetic tree suggests mixing between C. penicillata,
C. kuhli, and possibly C. jacchus. Most of the sequence features
characteristic of other mammal control regions were also evident in
marmosets, with the exception that conserved sequence blocks (CSBs) 2 and 3
were not clearly identifiable. Tandem repeat units often associated with
heteroplasmy in a variety of other mammals were not evident in the marmoset
sequences.
相似文献
28.
Maternal protein restriction during gestation and lactation in the rat results in increased brain levels of kynurenine and kynurenic acid in their adult offspring 下载免费PDF全文
29.
Hornung E Kunze S Liavonchanka A Zimmermann G Kühn D Fritsche K Renz A Kühn H Feussner I 《Phytochemistry》2008,69(16):2774-2780
Lipoxygenases (LOX) form a heterogeneous family of lipid peroxidizing enzymes, which catalyze specific dioxygenation of polyunsaturated fatty acids. According to their positional specificity of linoleic acid oxygenation plant LOX have been classified into linoleate 9- and linoleate 13-LOX and recent reports identified a critical valine at the active site of 9-LOX. In contrast, more bulky phenylalanine or histidine residues were found at this position in 13-LOX. We have recently cloned a LOX-isoform from Momordica charantia and multiple amino acid alignments indicated the existence of a glutamine (Gln599) at the position were 13-LOX usually carry histidine or phenylalanine residues. Analyzing the pH-dependence of the positional specificity of linoleic acid oxygenation we observed that at pH-values higher than 7.5 this enzyme constitutes a linoleate 13-LOX whereas at lower pH, 9-H(P)ODE was the major reaction product. Site-directed mutagenesis of glutamine 599 to histidine (Gln599His) converted the enzyme to a pure 13-LOX. These data confirm previous observation suggesting that reaction specificity of certain LOX-isoforms is not an absolute enzyme property but may be impacted by reaction conditions such as pH of the reaction mixture. We extended this concept by identifying glutamine 599 as sequence determinant for such pH-dependence of the reaction specificity. Although the biological relevance for this alteration switch remains to be investigated it is of particular interest that it occurs at near physiological conditions in the pH-range between 7 and 8. 相似文献
30.
Amann M Friedrich M Lutterbuese P Vieser E Lorenczewski G Petersen L Brischwein K Kufer P Kischel R Baeuerle PA Schlereth B 《Cancer immunology, immunotherapy : CII》2009,58(1):95-109
MuS110 is a BiTE antibody bispecific for murine EpCAM (CD326) and murine CD3. A recent study has shown that muS110 has significant
anti tumor activity at well-tolerated doses as low as 5 μg/kg in orthotopic breast and lung cancer models (Amann et al. in
Cancer Res 68:143–151, 2008). Here, we have explored the safety profile of muS110 at higher doses. Escalation to 50 μg/kg muS110 caused in mice transient
loss of body weight, and transient piloerection, hypomotility, hypothermia and diarrhoea. These clinical signs coincided with
serum peaks of TNF-α, IL-6, IL-2, IFN-γ and IL-4, and an increase of surface markers for T cell activation. Because activation
of T cells in response to BiTE antibodies is typically dependent on target cells, we analyzed mouse blood for the presence
of EpCAM+ cells. Various mouse strains presented with a subpopulation of 2–3% EpCAM+ blood cells, mostly B and T lymphocytes, which was not detected in human blood samples. In vitro experiments in which the
number of EpCAM+ cells in blood samples was either reduced or increased suggested that both T cell activation and cytokine release in response
to muS110 was dependent on the number of target-expressing cells. In support for a role of EpCAM+ lymphocytes in the observed side effects, reduction of EpCAM+ blood cells in mice via a low-dose pre treatment with muS110 dramatically increased the tolerability of animals up to at
least 500 μg/kg of the BiTE antibody. This high tolerability to muS110 occurred in the presence of non-compromised T cells.
No damage to EpCAM+ epithelial tissues was evident from histopathological examination of animals daily injected with 100 μg/kg muS110 for 28 days.
In summary, these observations suggest that side effects of muS110 in mice were largely caused by an acute T cell activation
that was triggered by a subpopulation of EpCAM+ lymphocytes. Because humans have extremely low numbers of EpCAM+ cells in blood, this toxicity of an EpCAM-specific BiTE may be specific for mice.
M. Amann and M. Friedrich contributed equally to this work. 相似文献