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101.
Development and characterization of highly polymorphic long TC repeat microsatellite markers for genetic analysis of peanut 总被引:4,自引:0,他引:4
Selma E Macedo Márcio C Moretzsohn Soraya C M Leal-Bertioli Dione MT Alves Ediene G Gouvea Vania CR Azevedo David J Bertioli 《BMC research notes》2012,5(1):1-10
Background
The immune system has paradoxical roles during cancer development and the prognostic significance of immune modulating factors is controversial. The aim of this study was to determine the expression of cyclooxygenase 2 (COX-2), transforming growth factor-beta (TGF- beta), interleukin-10 (IL-10) and their prognostic significance in breast cancers. Ki67 was included as a measure of growth fraction of tumor cells.Methods
On immunohistochemical stained slides from 38 breast cancer patients, we performed digital video analysis of tumor cell areas and adjacent tumor stromal areas from the primary tumors and their corresponding lymph node metastases. COX-2 was recorded as graded staining intensity.Results
The expression of TGF-beta, IL-10 and Ki67 were recorded in tumor cell areas and adjacent tumor stromal areas. In both primary tumors and metastases, the expression of COX-2 was higher in the tumor stromal areas than in the tumor cell areas (both P < 0.001). High stromal staining intensity in the primary tumors was associated with a 3.9 (95% CI 1.1-14.2) times higher risk of death compared to the low staining group (P = 0.036). The expression of TGF-beta was highest in the tumor cell areas of both primary tumors and metastases (both P < 0.001). High stromal expression of TGF-beta was associated with increased mortality. For IL-10, the stromal expression was highest in the primary tumors (P < 0.001), whereas in the metastases the expression was highest in tumor cell areas (P < 0.001). High IL-10 expression in tumor- and stromal cell areas of primary tumors predicted mortality. Ki67 was higher expressed in tumor stromal areas of the metastases, and in tumor cell areas of the primary tumors (P < 0.001). Ki67 expression in tumor cell areas and stromal areas of the metastases was independently associated with breast cancer mortality.Conclusions
Stromal expression of COX-2, TGF-beta and Ki67 may facilitate tumor progression in breast cancer. 相似文献102.
Sengle G Charbonneau NL Ono RN Sasaki T Alvarez J Keene DR Bächinger HP Sakai LY 《The Journal of biological chemistry》2008,283(20):13874-13888
Both latent transforming growth factor-beta (TGF-beta)-binding proteins fibrillins are components of microfibril networks, and both interact with members of the TGF-beta family of growth factors. Interactions between latent TGF-beta-binding protein-1 and TGF-beta and between fibrillin-1 and bone morphogenetic protein-7 (BMP-7) are mediated by the prodomain of growth factor complexes. To extend this information, investigations were performed to test whether stable complexes are formed by additional selected TGF-beta family members. Using velocity sedimentation in sucrose gradients as an assay, complex formation was demonstrated for BMP-7 and growth and differentiation factor-8 (GDF-8), which are known to exist in prodomain/growth factor complexes. Comparison of these results with complex formation by BMP-2, BMP-4 (full-length and shortened propeptides), BMP-10, and GDF-5 allowed us to conclude that all, except for BMP-2 and the short BMP-4 propeptides, formed complexes with their growth factors. Using surface plasmon resonance, binding affinities between fibrillin and all propeptides were determined. Binding studies revealed that the N-terminal end of fibrillin-1 serves as a universal high affinity docking site for the propeptides of BMP-2, -4, -7, and -10 and GDF-5, but not GDF-8, and located the BMP/GDF binding site within the N-terminal domain in fibrillin-1. Rotary shadowing electron microscopy of molecules of BMP-7 complex bound to fibrillin-1 confirmed these findings and also showed that prodomain binding targets the growth factor to fibrillin. Immunolocalization of BMP-4 demonstrated fibrillar staining limited to certain tissues, indicating tissue-specific targeting of BMP-4. These data implicate the fibrillin microfibril network in the extracellular control of BMP signaling and demonstrate differences in how prodomains target their growth factors to the extracellular space. 相似文献
103.
Background
There is a frequent need to obtain sets of functionally equivalent homologous proteins (FEPs) from different species. While it is usually the case that orthology implies functional equivalence, this is not always true; therefore datasets of orthologous proteins are not appropriate. The information relevant to extracting FEPs is contained in databanks such as UniProtKB/Swiss-Prot and a manual analysis of these data allow FEPs to be extracted on a one-off basis. However there has been no resource allowing the easy, automatic extraction of groups of FEPs – for example, all instances of protein C. 相似文献104.
Monoterpene emissions from ornamental trees in urban areas: a case study of Barcelona, Spain 总被引:1,自引:1,他引:0
Research on biogenic volatile organic compound (BVOC) emissions has mainly focused on native species in natural ecosystems. However, much of the ozone and aerosol formation occurs in city atmospheres due to BVOC emissions by local urban vegetation. Plant composition of urban habitats is often dominated by non-native ornamental plant species, for which only limited data on BVOC emissions are available. To gain insight into the influence of ornamental vegetation on the urban atmospheric reactivity in Barcelona, Spain, we studied volatile isoprenoid emissions in 11 widespread ornamental tree species (three conifers and nine angiosperms). We found significant monoterpene emissions in all studied species, with normalized emission potentials (T=30 degrees C, photosynthetic photon flux density (PPFD)=1000 micromol x m(-2) x s(-1)) ranging between 0.2 to 110 microg x g(-1) (dry weight) h(-1). Depending on species, the emissions were dominated by alpha- and beta-pinene, myrcene, alpha- and beta-phellandrene, carene, limonene and eucalyptol. These data demonstrate that ornamental plants may significantly contribute to the BVOC load in urban atmospheres and also underscore the importance of broadleaf angiosperms as significant monoterpene emitters. 相似文献
105.
Phosphorus cycling and partitioning in an oligotrophic Everglades wetland ecosystem: a radioisotope tracing study 总被引:4,自引:0,他引:4
Gregory B. Noe Leonard J. Scinto Jonathan Taylor Daniel L. Childers Ronald D. Jones 《Freshwater Biology》2003,48(11):1993-2008
1. Our goal was to quantify short‐term phosphorus (P) partitioning and identify the ecosystem components important to P cycling in wetland ecosystems. To do this, we added P radiotracer to oligotrophic, P‐limited Everglades marshes. 32PO4 was added to the water column in six 1‐m2 enclosed mesocosms located in long‐hydroperiod marshes of Shark River Slough, Everglades National Park. Ecosystem components were then repeatedly sampled over 18 days. 2. Water column particulates (>0.45 μm) incorporated radiotracer within the first minute after dosing and stored 95–99% of total water column 32P activity throughout the study. Soluble (<0.45 μm) 32P in the water column, in contrast, was always <5% of the 32P in surface water. Periphyton, both floating and attached to emergent macrophytes, had the highest specific activity of 32P (Bq g?131P) among the different ecosystem components. Fish and aquatic macroinvertebrates also had high affinity for P, whereas emergent macrophytes, soil and flocculent detrital organic matter (floc) had the lowest specific activities of radiotracer. 3. Within the calcareous, floating periphyton mats, 81% of the initial 32P uptake was associated with Ca, but most of this 32P entered and remained within the organic pool (Ca‐associated = 14% of total) after 1 day. In the floc layer, 32P rapidly entered the microbial pool and the labile fraction was negligible for most of the study. 4. Budgeting of the radiotracer indicated that 32P moved from particulates in the water column to periphyton and floc and then to the floc and soil over the course of the 18 day incubations. Floc (35% of total) and soil (27%) dominated 32P storage after 18 days, with floating periphyton (12%) and surface water (10%) holding smaller proportions of total ecosystem 32P. 5. To summarise, oligotrophic Everglades marshes exhibited rapid uptake and retention of labile 32P. Components dominated by microbes appear to control short‐term P cycling in this oligotrophic ecosystem. 相似文献
106.
2''-O-methyl, 2''-O-ethyl oligoribonucleotides and phosphorothioate oligodeoxyribonucleotides as inhibitors of the in vitro U7 snRNP-dependent mRNA processing event. 总被引:5,自引:5,他引:0
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M Cotten B Oberhauser H Brunar A Holzner G Issakides C R Noe G Schaffner E Wagner M L Birnstiel 《Nucleic acids research》1991,19(10):2629-2635
We describe the synthesis of 2'-O-methyl, 2'-O-ethyl oligoribonucleotides and phosphorothioate oligodeoxyribonucleotides and demonstrate their utility as inhibitors of the in vitro U7 snRNP-dependent mRNA processing event. These 2'-O-modified compounds were designed to possess the binding affinity of an RNA molecule towards a complementary RNA target with an enhanced stability against nucleases. The 2'-O-methyl and 2'-O-ethyl antisense compounds function as potent inhibitors of the reaction at 1-10 nM, approximately 5-fold more effective than a natural antisense RNA molecule and requiring an approximate 5-fold excess over the target RNA for 80% inhibition of the processing reaction. 相似文献
107.
A Raisonnier D Brault L Noe J Etienne J Hamelin J C Chuat I Dugail A Quignard-Boulange M Lavau F Galibert 《Comptes rendus des séances de la Société de biologie et de ses filiales》1992,186(6):666-681
Vertebrates' plasmatic apolipoproteins and a few number of lipases in their metabolism present sequence homologies. They are grouped in genes families. The four exons apolipoproteins gene family includes nine human genes: the divergence rate of their sequences allows to place the first ancestral gene very high in the phylogenetic tree of the evolution. However, a more recent duplication of apolipoprotein C-I gene dating from 40 millions years, may be a phylogenetic marker for the radiation of Monkeys. Pancreatic lipase and isoforms, lipoprotein-lipase and hepatic triacylglycerol-lipase form by their homologies a "superfamily" of genes, which also includes yolk proteins of Dipterians eggs. Sequence homologies of PL, LPL and HL are analysed and compared with multiple alignments of amino-acids and nucleotides on spreadsheets. From these comparisons we may characterize four classes of phylogenetic markers: 1) repetitive DNA sequence (Alu, B1, PRE-1) appeared during Mammals evolution, 2) short insertions or deletions (within N-terminal domain) and a gene conversion in guinea-pig lineage, 3) a progressive reduction of intron number during the lipases evolution, 4) several duplications of genes which have produced the five genes of this superfamily currently known in the human genome. 相似文献
108.
109.
John K. McDonald Francine Greiner John G. Wood Bryan D. Noe 《Cell and tissue research》1987,249(1):7-12
Summary Recent reports indicate that oxytocin exerts direct effects on the release of insulin and glucagon from the endocrine pancreas of the rat. The purpose of this study was to determine whether oxytocin-like immunoreactivity is present in the anglerfish islet, and if it is associated with subsets of hormone-producing cells. Antisera against oxytocin, insulin, glucagon, somatostatin, neuropeptide Y, and the 200 — kd neurofilament polypeptide were applied to serial 5 m sections of pancreatic islets. The antiserum to the 200 — kd neurofilament polypeptide labeled nerve bundles and axons, some of which were also stained with the oxytocin antiserum. Oxytocin immunoreactivity was observed in large nerves that branched into varicose fibers. These fibers were consistently associated only with clusters of insulin-producing cells. Successive application of oxytocin and insulin antisera to the same section provided additional verification of this relationship. Oxytocin-labeled nerves were not associated with cells immunoreactive to glucagon, somatostatin, or neuropeptide Y (anglerfish peptide Yg). The results demonstrate that oxytocin or an oxytocin-like peptide is located in fibers that surround only insulin-producing cells in the anglerfish islet. Although the functional significance of this observation remains to be determined, the results imply that oxytocin, or an oxytocin-like peptide, may affect the synthesis or release of insulin from anglerfish islets. 相似文献
110.
Modifications were made to published arbitrary primed polymerase chain reaction (AP-PCR) procedures that resulted in increased specificity and sensitivity. Several arbitrary primer sequences were also evaluated, resulting in recommendations for primer design. 相似文献