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91.
92.
Kaisa Luostari Jaana M. Hartikainen Maria Tengstr?m Jorma J. Palvimo Vesa Kataja Arto Mannermaa Veli-Matti Kosma 《PloS one》2014,9(7)
Type II transmembrane serine proteases (TTSPs) are related to tumor growth, invasion, and metastasis in cancer. Genetic variants in these genes may alter their function, leading to cancer onset and progression, and affect patient outcome. Here, 464 breast cancer cases and 370 controls were genotyped for 82 single-nucleotide polymorphisms covering eight genes. Association of the genotypes was estimated against breast cancer risk, breast cancer–specific survival, and survival in different treatment groups, and clinicopathological variables. SNPs in TMPRSS3 (rs3814903 and rs11203200), TMPRSS7 (rs1844925), and HGF (rs5745752) associated significantly with breast cancer risk (P
trend = 0.008–0.042). SNPs in TMPRSS1 (rs12151195 and rs12461158), TMPRSS2 (rs2276205), TMPRSS3 (rs3814903), and TMPRSS7 (rs2399403) associated with prognosis (P = 0.004–0.046). When estimating the combined effect of the variants, the risk of breast cancer was higher with 4–5 alleles present compared to 0–2 alleles (P = 0.0001; OR, 2.34; 95% CI, 1.39–3.94). Women with 6–8 survival-associating alleles had a 3.3 times higher risk of dying of breast cancer compared to women with 1–3 alleles (P = 0.001; HR, 3.30; 95% CI, 1.58–6.88). The results demonstrate the combined effect of variants in TTSPs and their related genes in breast cancer risk and patient outcome. Functional analysis of these variants will lead to further understanding of this gene family, which may improve individualized risk estimation and development of new strategies for treatment of breast cancer. 相似文献
93.
Jorma J. Ohisalo Ilmo E. Hassinen Jaakko P. Pispa 《Biochimica et Biophysica Acta (BBA)/General Subjects》1974,362(1):48-52
Hepatic tyrosine aminotransferase (l-tyrosine:2-oxoglutarate aminotransferase, EC 2.6.1.5) is known to be induced by α-methyl-p-tyrosine, a well-known catecholamine depletor, in both intact and adrenalectomized rats. The authors have studied this subject further and their results show that α-methyl-p-tyrosine does not influence the activity of tyrosine aminotransferase in the isolated, perfused liver and that hypophysectomy totally abolishes the induction of the enzyme by this agent. The involvement of hypophyseal hormones is discussed. 相似文献
94.
Granlund Lars Vesakoski Ville Sallinen Antti Kolari Tiina H. M. Wolff Franziska Tahvanainen Teemu 《Ecosystems》2022,25(7):1455-1475
Ecosystems - We investigated recent changes in spatial patterning of fen and bog zones in five boreal aapa mire complexes (mixed peatlands with patterned fen and bog parts) in a multiproxy study.... 相似文献
95.
96.
Changes of agricultural practices have led to decline of semi-natural habitats sustained by traditional animal husbandry in
many European regions. The abandonment of semi-natural pastures leads to increase of vascular plant biomass and subsequent
decline of weak competitors such as bryophytes. Re-establishing traditional animal husbandry may potentially restore biodiversity
but the success of such measures remains insufficiently known. In this study, we asked if re-establishing cattle grazing on
previously abandoned grasslands will restore their bryophyte communities. The effect of cattle grazing on bryophyte communities
of mesic semi-natural grasslands was studied in south-western Finland in a comparison of (i) continuously grazed pastures,
(ii) previously abandoned pastures where grazing was re-established during 1990s, and (iii) abandoned pastures, where grazing
had ceased during late 1960s to early 1980s. The average cover, species richness, species density and species diversity of
bryophytes were significantly higher in the continuously grazed than in the abandoned grasslands. Ordination analyses revealed
clear differences also in community structure between the management classes. Re-established grasslands were ecologically
heterogeneous and situated in between the continuously grazed and abandoned grasslands in all characteristics, indicating
variable effect of the restoration measure. Seventeen bryophyte species were recognized as significant indicators of the three
grassland classes, four of which could be used as indicators of valuable grassland habitats. Although there was variation
in the consequences of re-introduction of grazing, the results give evidence of positive effect of grazing on regaining bryophyte
diversity of abandoned grasslands. 相似文献
97.
Tamminen JA Myllärniemi M Hyytiäinen M Keski-Oja J Koli K 《Journal of cellular biochemistry》2012,113(7):2234-2247
The inhalation of asbestos fibers is considered to be highly harmful, and lead to fibrotic and/or malignant disease. Epithelial-to-mesenchymal transition (EMT) is a common pathogenic mechanism in asbestos associated fibrotic (asbestosis) and malignant lung diseases. The characterization of molecular pathways contributing to EMT may provide new possibilities for prognostic and therapeutic applications. The role of asbestos as an inducer of EMT has not been previously characterized. We exposed cultured human lung epithelial cells to crocidolite asbestos and analyzed alterations in the expression of epithelial and mesenchymal marker proteins and cell morphology. Asbestos was found to induce downregulation of E-cadherin protein levels in A549 lung carcinoma cells in 2-dimensional (2D) and 3D cultures. Similar findings were made in primary small airway epithelial cells cultured in 3D conditions where the cells retained alveolar type II cell phenotype. A549 cells also exhibited loss of cell-cell contacts, actin reorganization and expression of α-smooth muscle actin (α-SMA) in 2D cultures. These phenotypic changes were not associated with increased transforming growth factor (TGF)-β signaling activity. MAPK/Erk signaling pathway was found to mediate asbestos-induced downregulation of E-cadherin and alterations in cell morphology. Our results suggest that asbestos can induce epithelial plasticity, which can be interfered by blocking the MAPK/Erk kinase activity. 相似文献
98.
In somatic cells, integrity of cell division is safeguarded by the spindle checkpoint, a signaling cascade that delays the separation of sister chromatids in the presence of misaligned chromosomes. Aurora kinases play important roles in this process by promoting centrosome maturation, chromosome bi-orientation, spindle checkpoint signaling, and cytokinesis. To investigate the functions of Aurora kinases in male meiosis, we applied a small molecule Aurora inhibitor, ZM447439, to seminiferous tubules in vitro. Primary and secondary spermatocytes exposed to ZM447439 exhibit defects in the spindle morphology and fail to align their chromosomes at the metaphase plate. Moreover, the treated spermatocytes undergo a forced exit from the meiotic M-phase without cytokinesis. These results suggest that the activities of Aurora kinases are required for normal spindle assembly as well as for establishment and maintenance of proper microtubule-kinetochore attachments and spindle checkpoint signaling in male mammalian meiosis. 相似文献
99.
100.
Human whole saliva contains two peroxidases, salivary peroxidase (hSPO) and myeloperoxidase (hMPO), which are part of the innate host defence in oral cavity. Both hSPO as well as human milk lactoperoxidase (hLPO) are coded by the same gene, but to what extent the different producing glands, salivary and mammary glands, affect the final conformation of the enzymes is not known. In human saliva the major function of hSPO and hMPO is to catalyze the oxidation of thiocyanate (SCN(-)) in the presence of hydrogen peroxide (H(2)O(2)) resulting in end products of wide antimicrobial potential. In addition cytotoxic H(2)O(2) is degraded. Similar peroxidation reactions inactivate some mutagenic and carcinogenic compounds, which suggests another protective mechanism of peroxidases in human saliva. Although being target of an active antimicrobial research, the structure-function relationships of hSPO are poorly known. However, recently published method for recombinant hSPO production offers new tools for those investigations. 相似文献