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191.
Hans Knecht Silke Brüderlein Silke Wegener Daniel Lichtensztejn Zelda Lichtensztejn Bruno Lemieux Peter Möller Sabine Mai 《BMC cell biology》2010,11(1):99
Background
In cancer cells the three-dimensional (3D) telomere organization of interphase nuclei into a telomeric disk is heavily distorted and aggregates are found. In Hodgkin's lymphoma quantitative FISH (3D Q-FISH) reveals a major impact of nuclear telomere dynamics during the transition form mononuclear Hodgkin (H) to diagnostic multinuclear Reed-Sternberg (RS) cells. In vitro and in vivo formation of RS-cells is associated with the increase of very short telomeres including "t-stumps", telomere loss, telomeric aggregate formation and the generation of "ghost nuclei". 相似文献192.
Eun-Joo Kim Chang-Won Kang Nan-Hee Kim Yong Bae Seo Soo-Wan Nam Gun-Do Kim 《Biotechnology and Bioprocess Engineering》2018,23(2):201-207
Loranthus yadoriki, one of the Korean mistletoe species, has been already known for anti-viral effects, but the molecular basis that it caused apoptosis in cancer cells was not definitely revealed yet. The aim of this study was to estimate the mechanisms of apoptotic cell death of the extract from Loranthus yadoriki (named as ELY) in human cervix HeLa cells. We identified that ELY prevented the proliferation of HeLa cells between 50 and 300 μg/mL which did not affect non-cancerous HaCaT cells. In addition, ELY induced a morphological change and nucleus disruption as well as an accumulation of sub-G1 phase in HeLa cells. The mechanism study, by using western blot analysis, showed that the phosphorylation of Fas-associated death domain (FADD), Bim and Bak was up-regulated by ELY treatment. Furthermore, the expression of cytochrome c and Apaf-1 was increased by ELY treatment. In immunofluorescence staining, the increased intensity of cleaved caspase-3 and cleaved PARP was also observed under ELY treatment. Sequentially, the caspase cascade was activated by ELY from caspase-8 to caspase-3 and from caspase-9 to caspase-3, in both extrinsic and intrinsic pathways. The results of this study demonstrate that ELY has anti-cancer effects on human cervix cancer HeLa cells via caspase cascade in apoptotic signaling pathways. 相似文献
193.
Invading pathogens elicit potent immune responses in cells through interactions between structurally conserved molecules derived from the pathogens and specialized innate immune receptors such as the Toll-like receptors (TLRs). Nucleic acid is one of the principal TLR ligands. Nucleic acid-sensing TLRs recognize an array of nucleic acids, including double-stranded RNA, single-stranded RNA, and DNAs with specific sequence motifs. Although ligand-induced dimerization is commonly observed followed by TLR activation, both the specific recognition mechanisms and the ligand–receptor interactions vary among different TLRs. In this review, we highlight our current understanding of how these receptors recognize their cognate ligands based on the recent advances in structural biology. 相似文献
194.
Sam Shanee 《International journal of primatology》2011,32(3):691-707
Peruvian yellow-tailed woolly monkeys (Oreonax flavicauda) are considered Critically Endangered (IUCN Categories A4c). The International Primatological Society also considers them
one of the world’s 25 most endangered primate species and therefore a conservation priority. However, there is little concerted
conservation action, and the existing protected area network may be inadequate to protect this species from extinction. Until
recently this species has been the focus of few studies and its distributional limits remain unknown. I present results of
a range-wide survey of Oreonax flavicauda in northeastern Peru. I conducted 53 presence/absence field surveys at 43 sites between March 2007 and March 2010, with data
collected for an additional 7 sites from other researchers. I chose sites where the species was previously reported or following
suggestions from predictive GIS modeling. Oreonax flavicauda was present at 35 sites, all presence records were in Ficus spp.–dominated cloud forests between 1500 and 2650 m above sea level. I give the geographical limits of this species distribution
throughout the north, east, and west of its range; the exact extent of its range to the south requires further investigation.
Oreonax flavicauda continues to be threatened throughout its range. The major threats I identified at the survey locations were the continued
conversion of forests to cattle pasture, opening of new access routes into virgin areas, and both commercial and subsistence
hunting. My results suggest that existing conservation measures may be inadequate at protecting this species but that substantial
opportunities do exist. Further surveys need to be made in the southern distribution of this species to determine more accurately
extant habitat. 相似文献
195.
Christiane Anderson 《Brittonia》2018,70(2):248-251
Sphedamnocarpus andersonii, a new species from the Ihorombe Region of Madagascar, is described and illustrated. The twiggy, white-flowered shrubs are characterized by linear leaves, unique in the genus. 相似文献
196.
Plant-insect communities and predator-prey ratios in field margin strips,adjacent crop fields,and fallows 总被引:1,自引:0,他引:1
The management of field margin strips for the enhancement of biodiversity of plant-insect communities and natural-enemy populations was studied on experimental farms near Göttingen (Germany). Young and old, sown and naturally developed field margin strips were compared and differences to large fallows established. The five types of field margin strips (around cereal fields) were: (1, 2) 1- or 6-year-old naturally developed strips, (3) strips sown with a Phacelia mixture, (4) strips sown with a mixture of 19 wild flower species, and (5) strips sown with winter wheat or oat as a control. The naturally developed vegetation of the field margin strips was dominated by aggressive weeds, presumably due to the intensive farming practices and the fertile soils. Cirsium arvense populations decreased, while Elymus repens populations increased with age of habitat. Sowings were suitable to suppress these aggressive weeds. Potted plants of mugwort (Artemisia vulgaris) and red clover (Trifolium pratense) were exposed in the field margin strips to study arthropod colonization of these experimentally standardized plant patches. Arthropod species richness did not differ between field margin types, reflecting the overall similarity in floristic diversity, but sprayed and strip-free edges of cereal fields had a reduced diversity. Dispersal of insect populations of red clover into the cereal fields decreased with increasing distance, but benefited from adjacent field margin strips. Populations of predators (mainly spiders) as well as predator-prey ratios were significantly larger in 6-year-old than in 1-year-old strips emphasizing the importance of habitat age for natural enemies and possible biological control. Predator-prey ratios were also higher on old than young fallows. Large fallows had greater predator-prey ratios than small field margin strips emphasizing the trophic-level hypothesis of island biogeography in that the relative importance of natural enemies increased with habitat area. Insect species richness was only marginally influenced by area and not by age. As species richness of predators did not increase with area and age, species diversity and the possible biological-control function did not covary. 相似文献
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