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101.
Perez-Pinera P Garcia-Suarez O Menendez-Rodriguez P Mortimer J Chang Y Astudillo A Deuel TF 《Biochemical and biophysical research communications》2007,362(1):5-10
Increasing evidence suggests mutations in human breast cancer cells that induce inappropriate expression of the 18-kDa cytokine pleiotrophin (PTN, Ptn) initiate progression of breast cancers to a more malignant phenotype. Pleiotrophin signals through inactivating its receptor, the receptor protein tyrosine phosphatase (RPTP)beta/zeta, leading to increased tyrosine phosphorylation of different substrate proteins of RPTPbeta/zeta, including beta-catenin, beta-adducin, Fyn, GIT1/Cat-1, and P190RhoGAP. PTN signaling thus has wide impact on different important cellular systems. Recently, PTN was found to activate anaplastic lymphoma kinase (ALK) through the PTN/RPTPbeta/zeta signaling pathway; this discovery potentially is very important, since constitutive ALK activity of nucleophosmin (NPM)-ALK fusion protein is causative of anaplastic large cell lymphomas, and, activated ALK is found in other malignant cancers. Recently ALK was identified in each of 63 human breast cancers from 22 subjects. We now demonstrate that RPTPbeta/zeta is expressed in each of these same 63 human breast cancers that previously were found to express ALK and in 10 additional samples of human breast cancer. RPTPbeta/zeta furthermore was localized not only in its normal association with the cell membrane but also scattered in cytoplasm and in nuclei in different breast cancer cells and, in the case of infiltrating ductal carcinomas, the distribution of RPTPbeta/zeta changes as the breast cancer become more malignant. The data suggest that the PTN/RPTPbeta/zeta signaling pathway may be constitutively activated and potentially function to constitutively activate ALK in human breast cancer. 相似文献
102.
J Mangion N Rahman S Mansour G Brice J Rosbotham A H Child V A Murday P S Mortimer R Barfoot A Sigurdsson S Edkins M Sarfarazi K Burnand A L Evans T O Nunan M R Stratton S Jeffery 《American journal of human genetics》1999,65(2):427-432
Lymphedema-distichiasis (LD) is a dominantly inherited syndrome with onset of lymphedema at or just after puberty. Most affected individuals have distichiasis-fine hairs arising inappropriately from the eyelid meibomian glands-which is evident from birth. A study of three families with LD has shown linkage to chromosome 16q24.3, and subsequent analysis of the region for recombinant genes places the locus between D16S422 and D16S3074, a distance of approximately 16 cM. Possible candidate genes in this interval include the N-proteinase for type 3 collagen, PCOLN3; the metalloprotease PRSM1; and the cell matrix-adhesion regulator, CMAR. 相似文献
103.
Monoculture rubber cultivation and its intensive associated human activities are known to have a negative impact on the biodiversity, ecology, and biological conservation of the ecosystems in which they occur. These negative impacts include changes to the biodiversity and function of soil fungal communities, which contribute towards nutrient cycling and interact with other organisms in belowground ecosystems, and may be pathogens. Despite the important role of soil fungi in rubber plantations, these communities have been poorly studied. In this paper, we review the existing literature on the diversity and ecology of belowground fungi in rubber plantations. Various groups of soil fungi, including saprobes, symbionts, and pathogens are discussed. Additionally, the role of plantation management is discussed in the context of both pathogenic soil fungi and the promotion of beneficial soil fungi. Management practices include clone selection, tree age and planting density, application of chemicals, and intercropping systems. Our review shows the strong need for further research into the effects of monoculture rubber plantations on soil fungal communities, and how we can best manage these systems in the future, in order to create a more sustainable approach to rubber production. 相似文献
104.
105.
F. C. Connell P. Ostergaard C. Carver G. Brice N. Williams S. Mansour P. S. Mortimer Steve Jeffery Lymphoedema Consortium 《Human genetics》2009,124(6):625-631
Milroy disease (hereditary lymphoedema type I, MIM 153100) is a congenital onset primary lymphoedema with autosomal dominant
inheritance. Mutations in the gene, vascular endothelial growth factor receptor 3, VEGFR3 (FLT4), are known to cause Milroy disease, but there is uncertainty about the prevalence of VEGFR3 mutations in patients with primary lymphoedema and more specifically in those with a phenotype that resembles Milroy disease.
This study aims to address this issue and thereby delineate the Milroy disease phenotype. Fifty-two patients with primary
lymphoedema were analysed for mutations in the coding regions of VEGFR3. Patients were divided into four groups: Typical Milroy disease with family history (group I), typical Milroy disease with
no family history (group II), atypical Milroy disease (group III), and complex primary lymphoedema (group IV). Results demonstrated
that with rigorous phenotyping the likelihood of detecting VEGFR3 mutations is optimised. Mutation prevalence is 75% in typical Milroy patients with a family history (group I) and 68% if
positive family history is not a diagnostic criterion. A positive family history is not essential in Milroy disease. The likelihood
of detecting VEGFR3 mutations in patients who have a phenotype which is not typical of Milroy disease is very small (<5%). For the 22 mutation
positive patients, 14 novel VEGFR3 mutations were identified, two of which were in exon 22 and one in exon 17, confirming that these exons should be included
in VEGFR3 analysis. No mutations were found outside the kinase domains, showing that analysis of this part of the gene is not useful
for Milroy disease patients. VEGFC, which encodes the ligand for VEGFR3, was sequenced in all patients with typical Milroy disease (groups I and II) and no
mutations were identified.
F. C. Connell and P. Ostergaard contributed equally to this work.
An erratum to this article can be found at 相似文献
106.
S.?N.?BurgessEmail author M.?T.?McCulloch G.?E.?Mortimer T.?M.?Ward 《Coral reefs (Online)》2009,28(4):1005-1015
The high-latitude coral species Plesiastrea versipora was investigated to identify growth rates in colonies over 1 m in diameter. Six colonies from two temperate gulfs (latitudes
of 33°–35°S) in Southern Australia were examined using X-ray, luminescence and 238U/230Th dating techniques. Annual density bands were present in each coral but varied in width and definition, suggesting different
linear extension and calcification rates. Differences in density band width were observed at the local scale (amongst colonies
on the same reef) and regional scales (between the two gulfs). Extension rates of the P. versipora colonies examined in this study varied between 1.2 and 7 mm per year, which are amongst the slowest growth rates reported
for hermatypic corals. As only one of the six P. versipora colonies had obvious luminescent banding, we conclude that luminescent banding is not an accurate chronological marker in
this species of temperate water coral. Coral age estimates derived from counting density bands in X-radiographs ranged from
90 to 320 years for the six colonies studied. U-Th ages from the same colonies determined by high-precision multi-collector
inductively coupled plasma mass spectrometer established radiometric ages between 105 and 381 years. The chronological variation
in absolute ages between the two techniques varied between 2 and 19% in different colonies, with the lowest growth rates (~1 mm)
displaying the greatest variation between density band age and radiometric U-Th age. This result implies that the age of P. versipora and other slow-growing corals cannot be determined accurately from density bands alone. The outcome of this research demonstrates
that P. versipora may be useful as a paleoclimate archive, recording several centuries in a single colony in high-latitude environments (corals
found in latitudes greater than 30° in either hemisphere), where other well-established coral climate archives, such as Porites, do not occur. 相似文献
107.
108.
In this study, the relationship between the concentration of extra-heavy crude petroleum in a clayey material and the toxicity, field capacity, temperature, and growth of a tropical forage grass (Brachiara humidicola) was determined empirically. For this type of petroleum the acute toxicity (Microtox®) was slight (CE50 = 63200 - 76400 mg/kg) even at high hydrocarbon concentrations (29279 mg/kg). Nonetheless, serious impacts were encountered in terms of an increase in soil temperature (+ 1.3 °C), reduction in field capacity (-10.7%) and reduction in aerial biomass (-97%). The relationship between hydrocarbon concentration and biomass resulted in a typical dose-response curve (r = 0.99), where a concentration of 2626 mg/kg of hydrocarbons corresponds to a maintenance of 90% biomass. Furthermore, during the duration of this study (one year) the biodegradation was proportional to the pasture biomass production (r = 0.997) indicating a synergistic relationship between the petroleum biodegrading microorganisms in the rhizosphere and the pasture. 相似文献
109.
110.
William J. Sutherland Rosalind Aveling Thomas M. Brooks Mick Clout Lynn V. Dicks Liz Fellman Erica Fleishman David W. Gibbons Brandon Keim Fiona Lickorish Kathryn A. Monk Diana Mortimer Lloyd S. Peck Jules Pretty Johan Rockström Jon Paul Rodríguez Rebecca K. Smith Mark D. Spalding Femke H. Tonneijck Andrew R. Watkinson 《Trends in ecology & evolution》2014