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111.
Takeshi Nishimura Akichika Mikami Juri Suzuki Tetsuro Matsuzawa 《International journal of primatology》2007,28(2):483-492
Though many nonhuman primates possess a laryngeal sac, the great apes are unique in their great size. Though an enlarged sac
probably arose in their common ancestor, its functional adaptations remain a matter of debate. Its development in extant great
apes is likely to provide valuable information to clarify the issue. We used magnetic resonance imaging to examine the development
of the laryngeal sac in 3 living chimpanzees, age 4 mo–5 yr, and identified 2 distinct growth phases of the sac. A gradual
growth of the sac in early infancy results in a configuration so that it occupies the ventral region of the neck; many adult
nonhominoid primates having a sac show the configuration. The subsequent rapid expansion of the sac in late infancy causes
the final configuration in chimpanzees, wherein the sac expands into the pectoral, clavicular, and axillary regions. The latter
phase possibly arose at latest in the last common ancestor of extant great apes and contributed to the evolution of the enlarged
sac, despite the later evolutionary diversification in adult sac anatomy and growth. As many studies have advocated, the enlarged
sac probably plays a role in vocalization in adults. However, physiological modifications in the laryngeal region during infancy
are likely to provide valuable information to evaluate the functional adaptations of the enlarged sac in the great apes. 相似文献
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114.
Albina Orlova Imre Törö Vesna Hodnik Yosuke Senju Juan Zou Claudia Schreiner Julia Steiner Jari Meriläinen Marko Nikki Oliviero Carugo Juri Rappsilber Pekka Lappalainen Veli‐Pekka Lehto Gregor Anderluh Edward H Egelman Kristina Djinović‐Carugo 《EMBO reports》2014,15(11):1154-1162
Two mechanisms have emerged as major regulators of membrane shape: BAR domain‐containing proteins, which induce invaginations and protrusions, and nuclear promoting factors, which cause generation of branched actin filaments that exert mechanical forces on membranes. While a large body of information exists on interactions of BAR proteins with membranes and regulatory proteins of the cytoskeleton, little is known about connections between these two processes. Here, we show that the F‐BAR domain protein pacsin2 is able to associate with actin filaments using the same concave surface employed to bind to membranes, while some other tested N‐BAR and F‐BAR proteins (endophilin, CIP4 and FCHO2) do not associate with actin. This finding reveals a new level of complexity in membrane remodeling processes. 相似文献
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117.
Prdm5 regulates collagen gene transcription by association with RNA polymerase II in developing bone
118.
Michal Gropp Vitali Shilo Gilad Vainer Miri Gov Yaniv Gil Hanita Khaner Limor Matzrafi Maria Idelson Juri Kopolovic Naomi B. Zak Benjamin E. Reubinoff 《PloS one》2012,7(9)
Teratoma tumor formation is an essential criterion in determining the pluripotency of human pluripotent stem cells. However, currently there is no consistent protocol for assessment of teratoma forming ability. Here we present detailed characterization of a teratoma assay that is based on subcutaneous co-transplantation of defined numbers of undifferentiated human embryonic stem cells (hESCs) with mitotically inactivated feeder cells and Matrigel into immunodeficient mice. The assay was highly reproducible and 100% efficient when 100,000 hESCs were transplanted. It was sensitive, promoting teratoma formation after transplantation of 100 hESCs, though larger numbers of animals and longer follow-up were required. The assay could detect residual teratoma forming cells within differentiated hESC populations however its sensitivity was decreased in the presence of differentiated cells. Our data lay the foundation, for standardization of a teratoma assay for pluripotency analysis. The assay can also be used for bio-safety analysis of pluripotent stem cell-derived differentiated progeny. 相似文献
119.
Renata Jurišić Grubešić Dario Kremer Sanda Vladimir-Knežević Jadranka Vuković Rodríguez 《Central European Journal of Biology》2012,7(3):542-550
Total polyphenols, tannins, β-sitosterol, and bitterness values were determined in native and cultivated populations of Teucrium L. species from Croatia (T. arduini L., T. botrys L., T. chamaedrys L., T. flavum L., T. montanum L., T. polium L., and T. scordium L. subsp. scordioides Schreb.). Teucrium species have long been present in folk medicine for diverse medicinal uses, but little is known about polyphenols, phytosterols,
and bitter principles. Spectrophotometrically determined contents of total polyphenols (TP) and tannins (T) significantly
varied among investigated Teucrium species and were somewhat higher in native populations. The highest TP and T contents were measured in native specimens of
T. montanum (TP: 13.68%; T: 3.48%). Scanning densitometry was used for measurements of β-sitosterol levels in plant samples ranged from
0.056% (T. montanum) to 0.129% (T. botrys), and it was not significantly different between native and cultivated specimens of the same plant species. Bitterness values
were similar for native and cultivated samples of the same plant species; the highest was measured for T. montanum (15659). The present study suggests that Teucrium species growing in Croatia have potential for cultivation and might be a valuable source of natural bioactive compounds. 相似文献