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291.
292.
T. R. Kaisa 《Journal of nematology》2000,32(4):396-402
Aphelenchoides microstylus n. sp. and Seinura onondagensis n. sp., a nematode predator, are described from dead Scots pine (Pinus sylvestris L.) in Onondaga County, New York. Females of A. microstylus are 370 to 485 µm long. The body is slender and tapers posteriorly to an amucronate, pointed terminus. The head is continuous with the body, and lips bear a stylet guide. Diagnostic characters of females are three incisures in the lateral field, a short stylet (6-7.5 µm) with small basal knobs, a single row of oocytes, and a long postuterine sac (25-50 µm). Males are characterized by small spicules (10-11µm); two pairs of post-anal, subventral papillae; and a single row of spermatocytes. A bursa and gubernaculum are absent. Seinura onondagensis females are characterized by a body of moderate length (475-595 µm), finely annulated cuticle, and a slightly set-off head. Diagnostic characters are four incisures in the lateral field, long stylet without basal knobs (17-22 µm), single row of oocytes, and presence of a postuterine sac (14-38 µm). Males are unknown. The monospecific genus Indaphelenchus is proposed as a synonym of Seinura, and S. siddiqii n. comb. is proposed for the only species, I. siddiqii. 相似文献
293.
Alok Jaiswal Prson Gautam Elina A Pietil Sanna Timonen Nora Nordstrm Yevhen Akimov Nina Sipari Ziaurrehman Tanoli Thomas Fleischer Kaisa Lehti Krister Wennerberg Tero Aittokallio 《Molecular systems biology》2021,17(3)
Molecular and functional profiling of cancer cell lines is subject to laboratory‐specific experimental practices and data analysis protocols. The current challenge therefore is how to make an integrated use of the omics profiles of cancer cell lines for reliable biological discoveries. Here, we carried out a systematic analysis of nine types of data modalities using meta‐analysis of 53 omics studies across 12 research laboratories for 2,018 cell lines. To account for a relatively low consistency observed for certain data modalities, we developed a robust data integration approach that identifies reproducible signals shared among multiple data modalities and studies. We demonstrated the power of the integrative analyses by identifying a novel driver gene, ECHDC1, with tumor suppressive role validated both in breast cancer cells and patient tumors. The multi‐modal meta‐analysis approach also identified synthetic lethal partners of cancer drivers, including a co‐dependency of PTEN deficient endometrial cancer cells on RNA helicases. 相似文献
294.
295.
Birch PR-10c is induced by factors causing oxidative stress but appears not to confer tolerance to these agents 总被引:2,自引:0,他引:2
296.
Spatial heterogeneity and dynamics of vernal phytoplankton species in the Baltic Sea in April-May 1986 总被引:2,自引:0,他引:2
Kononen Kaisa; Nommann Sulev; Hansen Gesa; Hansen Regina; Breuel Gunter; Gupalo Ekaterina 《Journal of plankton research》1992,14(1):107-125
The mesoscale phytoplankton distribution was studied as partof an international joint Baltic Sea Patchiness Experiment (PEX'86)during AprilMay 1986 in the open Baltic Proper. The studyperiod covered the peak phase of the phytoplankton spring bloom.The spatio-temporal dynamics of four dominating phytoplanktonspecies, Achnanthes taeniata, Chaetoceros spp., Skeletonemacostatum and Thalassiosira levanderi were studied within anarea of 20x40 nmi with grids of 2 and 4 nmi spatial resolution.The results showed highly varying spatial distributions forall species, and the variability was accentuated on the synopticspace scale before the development of the seasonal thermocline.The maxima of Chaetoceros spp. and Thalassiosira levanderi coincidedwith the anticyclonic and cyclonic eddies prevailing in thearea. Skeletonema costatum was found in high abundances onlywithin a warmer water mass of higher salinity advecting intothe area. The results pointed out that different successionalstages can simultaneously be found even in adjacent water massesand both the phytoplankton growth and composition during thebloom peak phase in the Central Baltic depend on complex factors,mainly those connected with mesoscale hydrodynamic features(eddies, frontal zones, jet currents). 相似文献
297.
Zhida Wu Meiling Zuo Ling Zeng Kaisa Cui Bing Liu Chaojun Yan Li Chen Jun Dong Fugen Shangguan Wanglai Hu He He Bin Lu Zhiyin Song 《EMBO reports》2021,22(1)
Many cancer cells maintain enhanced aerobic glycolysis due to irreversible defective mitochondrial oxidative phosphorylation (OXPHOS). This phenomenon, known as the Warburg effect, is recently challenged because most cancer cells maintain OXPHOS. However, how cancer cells coordinate glycolysis and OXPHOS remains largely unknown. Here, we demonstrate that OMA1, a stress‐activated mitochondrial protease, promotes colorectal cancer development by driving metabolic reprogramming. OMA1 knockout suppresses colorectal cancer development in AOM/DSS and xenograft mice models of colorectal cancer. OMA1‐OPA1 axis is activated by hypoxia, increasing mitochondrial ROS to stabilize HIF‐1α, thereby promoting glycolysis in colorectal cancer cells. On the other hand, under hypoxia, OMA1 depletion promotes accumulation of NDUFB5, NDUFB6, NDUFA4, and COX4L1, supporting that OMA1 suppresses OXPHOS in colorectal cancer. Therefore, our findings support a role for OMA1 in coordination of glycolysis and OXPHOS to promote colorectal cancer development and highlight OMA1 as a potential target for colorectal cancer therapy. 相似文献
298.
Centrosomal ALIX regulates mitotic spindle orientation by modulating astral microtubule dynamics 下载免费PDF全文
Lene Malerød Åsmund Husabø Eikenes Andreas Brech Knut Liestøl Harald Stenmark Kaisa Haglund 《The EMBO journal》2018,37(13)
The orientation of the mitotic spindle (MS) is tightly regulated, but the molecular mechanisms are incompletely understood. Here we report a novel role for the multifunctional adaptor protein ALG‐2‐interacting protein X (ALIX) in regulating MS orientation in addition to its well‐established role in cytokinesis. We show that ALIX is recruited to the pericentriolar material (PCM) of the centrosomes and promotes correct orientation of the MS in asymmetrically dividing Drosophila stem cells and epithelial cells, and symmetrically dividing Drosophila and human epithelial cells. ALIX‐deprived cells display defective formation of astral microtubules (MTs), which results in abnormal MS orientation. Specifically, ALIX is recruited to the PCM via Drosophila Spindle defective 2 (DSpd‐2)/Cep192, where ALIX promotes accumulation of γ‐tubulin and thus facilitates efficient nucleation of astral MTs. In addition, ALIX promotes MT stability by recruiting microtubule‐associated protein 1S (MAP1S), which stabilizes newly formed MTs. Altogether, our results demonstrate a novel evolutionarily conserved role of ALIX in providing robustness to the orientation of the MS by promoting astral MT formation during asymmetric and symmetric cell division. 相似文献
299.
Green-tree retention is a relatively new forestry application, which aims at decreasing the negative effects of clear-cut
logging on forest biodiversity. In this study, the value of retained aspens in maintaining diverse assemblages of wood-decaying
fungi (polypores; Basidiomycota) on clear-cuts was investigated, after the retention trees had died, fallen and started to
decay. A total of 110 fallen aspen trunks were investigated on clear-cuts and within old-growth forests in eastern Finland,
southern boreal zone; and 499 records of polypores belonging to 46 species were made. The intermediately decayed trunks on
a clear-cut area hosted more species and more red-listed species than did trunks within forests. Most of the polypore species
with more than two records were found in both habitats. These results suggest that many aspen-associated polypores are able
to live and reproduce in sun-exposed habitats, if the quality and quantity of dead wood fulfill the species-specific requirements.
This unexpected result, however, may be partly due to the exceptionally great abundance of aspen in the study area. Furthermore,
in the long term, the local benefits of fallen retention trees can be limited, unless the local continuity of large aspens,
both living and dead, is ensured. 相似文献
300.
Laura Huilaja Tiina Hurskainen Helena Autio-Harmainen Silke C Hofmann Raija Sormunen Juha R?s?nen Mika Ilves Claus-Werner Franzke Leena Bruckner-Tuderman Kaisa Tasanen 《Matrix biology》2008,27(3):190-200
In pemphigoid gestationis (PG), autoantibodies target collagen XVII, a hemidesmosomal transmembrane protein, which is an important element in cutaneous epithelial adhesion and signalling. We report that collagen XVII is expressed in the first trimester and term syncytial and cytotrophoblastic cells of normal placenta and in epithelial cells of amniotic membrane. Immunoelectron microscopy confirmed the localization of collagen XVII to the hemidesmosomes of amniotic epithelium. Examination of three PG placentas showed mild villitis, but there were no differences between collagen XVII expression levels or immunostaining signals as compared to normal placenta. Collagen XVII expression was also detected in cultured extravillous trophoblast HTR-8/SVneo cells, where collagen XVII expression was upregulated by PMA and TGF-beta1. Interestingly, the presence of Col15, the cell migration domain of collagen XVII, induced the migration of HTR-8/SVneo cells in transmigration assay. Analysis of amniotic fluid samples at different gestational weeks revealed that a large quantity of collagen XVII ectodomain was shed into amniotic fluid throughout pregnancy. Biochemical and immunoblotting analysis indicated that the ectodomain in amniotic fluid is structurally very similar to the ectodomain produced by cultured keratinocytes. Cultured cells from amniotic fluid samples also expressed collagen XVII. Our results suggest that collagen XVII may contribute to the invasion of extravillous trophoblasts during placental development and is also required for the integrity of amniotic basement membrane. Although the exact pathomechanism of PG is still largely unknown, the clinical symptoms of PG are initiated after the expression of collagen XVII in placenta during the first trimester of pregnancy. 相似文献