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941.
Platycarpum vriesendorpiae sp. nov., a second new species of Tribe Henriquezieae (Rubiaceae) from nutrient‐poor soils in the Peruvian Amazon 下载免费PDF全文
The new species Platycarpum vriesendorpiae N. Dávila (Rubiaceae, Henriquezieae) is described from Peru, where it is restricted to white‐sand forests and peatlands in the Tapiche and Blanco River watersheds in southeastern Loreto Region. The new species is generally similar to P. acreanum Rogers of western Brazil in its phyllotaxy, leaf pubescence, and fruit shape and size. However, P. vriesendorpiae differs in its triangular stipules that are 2‐ or 3‐angled at the base and in its smaller corolla. 相似文献
942.
Interactions between corals and associated bacteria and amongst these bacterial groups are likely to play a key role in coral
health. However, the complexity of these interactions is poorly understood. We investigated the functional role of specific
coral-associated bacteria in maintaining microbial communities on the coral Acropora millepora (Ehrenberg 1834) and the ability of coral mucus to support or inhibit bacterial growth. Culture-independent techniques were
used to assess bacterial community structures whilst bacterial culture was employed to assess intra- and inter-specific antimicrobial
activities of bacteria. Members of Pseudoalteromonas and ribotypes closely related to Vibrio coralliilyticus displayed potent antimicrobial activity against a range of other cultured isolates and grew readily on detached coral mucus.
Although such bacterial ribotypes would be expected to have a competitive advantage, they were rare or absent on intact and
healthy coral colonies growing in situ (analysed using denaturing gradient gel electrophoresis and 16S rRNA gene sequencing).
The most abundant bacterial ribotypes found on healthy corals were Gammaproteobacteria, previously defined as type A coral
associates. Our results indicate that this group of bacteria and specific members of the Alphaproteobacteria described here
as ‘type B associates’ may be important functional groups for coral health. We suggest that bacterial communities on coral
are kept in check by a combination of host-derived and microbial interactions and that the type A associates in particular
may play a key role in maintaining stability of microbial communities on healthy coral colonies. 相似文献
943.
Katharina L. Kopp Ulrik Ralfkiaer Lise Mette R. Gjerdrum Rikke Helvad Ida H. Pedersen Thomas Litman Lars J?nson Peter H. Hagedorn Thorbj?rn Krejsgaard Robert Gniadecki Charlotte M. Bonefeld Lone Skov Carsten Geisler Mariusz A. Wasik Elisabeth Ralfkiaer Niels ?dum Anders Woetmann 《Cell cycle (Georgetown, Tex.)》2013,12(12):1939-1947
944.
Thibaud Metzger Charlotte Kleiss Izabela Sumara 《Cell cycle (Georgetown, Tex.)》2013,12(14):2291-2296
Posttranslational mechanisms drive fidelity of cellular processes. Phosphorylation and ubiquitination of substrates represent very common, covalent, posttranslational modifications and are often co-regulated. Phosphorylation may play a critical role both by directly regulating E3-ubiquitin ligases and/or by ensuring specificity of the ubiquitination substrate. Importantly, many kinases are not only critical regulatory components of these pathways but also represent themselves the direct ubiquitination substrates. Recent data suggest the role of CUL3-based ligases in both proteolytic and non-proteolytic regulation of protein kinases. Our own recent study identified the mitotic kinase PLK1 as a direct target of the CUL3 E3-ligase complex containing BTB-KELCH adaptor protein KLHL22.1 In this study, we aim at gaining mechanistic insights into CUL3-mediated regulation of the substrates, in particular protein kinases, by analyzing mechanisms of interaction between KLHL22 and PLK1. We find that kinase activity of PLK1 is redundant for its targeting for CUL3-ubiquitination. Moreover, CUL3/KLHL22 may contact 2 distinct motifs within PLK1 protein, consistent with the bivalent mode of substrate targeting found in other CUL3-based complexes. We discuss these findings in the context of the existing knowledge on other protein kinases and substrates targeted by CUL3-based E3-ligases. 相似文献
945.
Charlotte Ytterberg Sverker Johansson Kristina Gottberg Lotta Widén Holmqvist Lena von Koch 《BMC neurology》2008,8(1):36
Background
Considering the costs of multiple sclerosis (MS), it is crucial that the health-related services supplied are in accordance with needs as they are perceived by people with MS (PwMS). Satisfaction with care is related to quality of care and can provide health care providers with the means for improvement. The aim was to explore the perceived needs and satisfaction with care amongst PwMS over a two-year period, also taking sex and disease severity into consideration. 相似文献946.
947.
Cole CG McCann OT Collins JE Oliver K Willey D Gribble SM Yang F McLaren K Rogers J Ning Z Beare DM Dunham I 《Genome biology》2008,9(5):R78-11
Background
Although the human genome sequence was declared complete in 2004, the sequence was interrupted by 341 gaps of which 308 lay in an estimated approximately 28 Mb of euchromatin. While these gaps constitute only approximately 1% of the sequence, knowledge of the full complement of human genes and regulatory elements is incomplete without their sequences.Results
We have used a combination of conventional chromosome walking (aided by the availability of end sequences) in fosmid and bacterial artificial chromosome (BAC) libraries, whole chromosome shotgun sequencing, comparative genome analysis and long PCR to finish 8 of the 11 gaps in the initial chromosome 22 sequence. In addition, we have patched four regions of the initial sequence where the original clones were found to be deleted, or contained a deletion allele of a known gene, with a further 126 kb of new sequence. Over 1.018 Mb of new sequence has been generated to extend into and close the gaps, and we have annotated 16 new or extended gene structures and one pseudogene.Conclusion
Thus, we have made significant progress to completing the sequence of the euchromatic regions of human chromosome 22 using a combination of detailed approaches. Our experience suggests that substantial work remains to close the outstanding gaps in the human genome sequence. 相似文献948.
Shao R Nutu M Weijdegård B Egecioglu E Fernandez-Rodriguez J Tallet E Goffin V Ling C Billig H 《Biology of reproduction》2008,79(4):748-757
The anterior pituitary-derived hormone prolactin (PRL) signals through the PRL receptor (PRLR) and is important for female reproductive function in mammals. In contrast to the extensive studies of PRLR expression and regulation in human and mouse ovary and uterus, the mechanisms controlling the regulation of PRLR isoform expression in the fallopian tube are poorly understood. Because dynamic interaction of hormonal signaling in gonadal tissue and the pituitary or in gonadal tissues themselves in mammals suggests endocrine or paracrine regulation of PRLR expression, we questioned whether differential regulation of PRLR isoforms by PRL ovarian-derived estrogen (E(2)) and progesterone (P(4)) exists in the fallopian tube and pituitary of prepubertal female mice. Western blot analysis showed distinct molecular separation of PRLR isoforms in mouse and human fallopian tubes, and cellular localization was found in mouse and human tubal epithelia but not in mouse tubal smooth muscle cells. These data support the concept of an isoform- and cell type-specific expression of PRLR in human and mouse fallopian tubes. Moreover, expression of the long form of PRLR decreased after PRL treatment and increased after blockage of endogenous PRL secretion by bromocriptine (an inhibitor of PRL secretion) in a time-dependent manner in mouse fallopian tube. The opposite regulation was observed in the pituitary. Treatment with exogenous E(2) or P(4) led to changes in PRLR expression in the fallopian tube similar to those of PRL treatment. However, E(2) and P(4) did not affect PRLR expression in the pituitary. Estrogen had no effect on the long form of PRLR expression, whereas P(4) regulated the long form of PRLR in the fallopian tube, as did PRL. Taken together, the data from our comparative study provide evidence that PRLR can be regulated by an interplay of two different mechanisms, PRL or ovarian steroid hormones independently or in combination in a tissue-specific manner. Furthermore, we found that ovarian steroid hormones selectively suppress the expression of PRLR isoforms in mouse fallopian tubes. These findings may contribute to our understanding of the mechanisms controlling PRLR isoform expression in the fallopian tube (in addition to ovary and uterus), with implications for female reproduction. 相似文献
949.
Language and cultural beliefs play an extremely important role in the interaction between patients from diverse cultural groups and physicians. Especially in emergency rooms, there are many dangers in missed communications. A patient from a foreign culture, especially one who does not speak English, often expresses symptoms in ways that are unfamiliar to many American physicians. Specific areas of cultural vulnerability can be identified for the major ethnic groups in the United States as they interact with the scientific medical system. A short review of folk medical beliefs and recommendations for improving diagnostic accuracy and treatment may assist emergency room staffs in offering care that is culturally acceptable to patients of diverse ethnic backgrounds. 相似文献
950.
Charlotte Steendam Pieterjan Verhelst Sam Van Wassenbergh Jens De Meyer 《Journal of fish biology》2020,97(5):1332-1342
The European eel (Anguilla anguilla) is a fascinating species, exhibiting a complex life cycle. The species is, however, listed as critically endangered on the IUCN Red List due to an amalgam of factors, including habitat loss. This study investigated the burrowing behaviour and substrate preference of glass, elver and yellow stages of A. anguilla. Preference was determined by introducing eels in aquaria with different substrates and evaluating the chosen substrate for burrowing. In addition, burrowing was recorded using a camera in all substrate types and analysed for kinematics. The experiments showed that all of these life stages sought refuge in the sediments with particle sizes ranging from sand to coarse gravel. Starting from a resting position, they shook their head horizontally in combination with rapid body undulations until half of their body was within the substrate. High-speed X-ray videography revealed that once partly in the sediment, eels used only horizontal head sweeps to penetrate further, without the use of their tail. Of the substrates tested, burrowing performance was highest in fine gravel (diameter 1–2 mm; lower burrowing duration, less body movements and/or lower frequency of movements), and all eels readily selected this substrate for burrowing. However, glass eels and elvers were able to use coarse gravel (diameter >8 mm) because their smaller size allowed manoeuvring through the spaces between the grains. Further, burrowing performance increased with body size: glass eels required more body undulations compared to yellow eels. Interestingly, the urge to hide within the sediment was highest for glass eels and elvers. Documentation of substrate preference and burrowing behaviour of A. anguilla provides new information about their potential habitat use. Considering that habitat alterations and deteriorations are partly responsible for the decline of the eel, this information can contribute to the development of more effective conservation measures. 相似文献