bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seed 1-Cysteine Peroxiredoxin Antioxidants Are Not Involved in Dormancy, But Contribute to Inhibition of Germination during Stress
Authors: Haslekås Camilla , Viken Marte K. , Grini Paul E. , Nygaard Vigdis , Nordgard Silje H. , Meza Trine J. , Aalen Reidunn B. 
Published: November 2003

Abstract
Peroxiredoxins (Prx) are thiol-dependent antioxidants containing one (1-cysteine [-Cys]) or two (2-Cys) conserved Cys residues that protect lipids, enzymes, and DNA against reactive oxygen species. In plants, the 1-Cys Prxs are highly expressed during late seed development, and the expression pattern is dormancy related in mature seeds. We have expressed the Arabidopsis 1-Cys Prx AtPER1 in Escherichia coli and show that this protein has antioxidant activity in vitro and protects E. coli in vivo against the toxic oxidant cumene hydroperoxide. Although some 1-Cys Prxs are targeted to the nucleus, a green fluorescent protein-AtPER1 fusion protein was also localized to the cytoplasm in an onion epidermis subcellular localization assay. It has been proposed that seed Prxs are involved in maintenance of dormancy and/or protect the embryo and aleurone layer surviving desiccation against damage caused by reactive oxygen species. These hypotheses were tested using transgenic Arabidopsis lines overexpressing the barley (Hordeum vulgare) 1-Cys PER1 protein and lines with reduced levels of AtPER1 due to antisensing or RNA interference. We found no correlation between Prx levels and the duration of the after-ripening period required before germination. Thus, Prxs are unlikely to contribute to maintenance of dormancy. RNA interference lines almost devoid of AtPER1 protein developed and germinated normally under standard growth room conditions. However, seeds from lines overexpressing PER1 were less inclined to germinate than wild-type seeds in the presence of NaCl, mannitol, and methyl viologen, suggesting that Prx can sense harsh environmental surroundings and play a part in the inhibition of germination under unfavorable conditions.
Two Lily SEPALLATA-Like Genes Cause Different Effects on Floral Formation and Floral Transition in Arabidopsis
Authors: Tzeng Tsai-Yu , Hsiao Chih-Chi , Chi Pei-Ju , Yang Chang-Hsien 
Published: November 2003

Abstract
Two AGL2-like MADS-box genes, Lily MADS Box Gene (LMADS) 3 and LMADS4, with extensive homology of LMADS3 to the Arabidopsis SEPALLATA3 were characterized from the lily (Lilium longiflorum). Both LMADS3 and LMADS4 mRNA were detected in the inflorescence meristem, in floral buds of different developmental stages, and in all four whorls of the flower organ. LMADS4 mRNA is also expressed in vegetative leaf and in the inflorescence stem where LMADS3 expression is absent. Transgenic Arabidopsis, which ectopically expresses LMADS3, showed novel phenotypes by significantly reducing plant size, flowering extremely early, and loss of floral determinacy. By contrast, 35S::LMADS4 transgenic plants were morphologically indistinguishable from wild-type plants. The early-flowering phenotype in 35S::LMADS3 transgenic Arabidopsis plants was correlated with the up-regulation of flowering time genes FT, SUPPRESSOR OF OVEREXPRESSION OF CO 1, LUMINIDEPENDENS, and flower meristem identity genes LEAFY and APETALA1. This result was further supported by the ability of 35S::LMADS3 to rescue the late-flowering phenotype in gigantea-1 (gi-1), constans-3 (co-3), and luminidependens-1 but not for ft-1 or fwa-1 mutants. The activation of these flowering time genes is, however, indirect because their expression was unaffected in plants transformed with LMADS3 fused with rat glucocorticoid receptor in the presence of both dexamethasone and cycloheximide.
Identification of a Locus Increasing Rice Yield and Physiological Analysis of Its Function
Authors: Ishimaru Ken 
Published: November 2003

Abstract
I identified a new locus responsible for increased yield potential and evaluated its physiological function to understand how to improve potential yield in rice (Oryza sativa) plants. Quantitative trait loci (QTLs) for 1,000-grain weight (TGW) were analyzed under different environments over 3 years in backcross inbred lines of rice japonica cv Nipponbare × indica cv Kasalath. Four QTLs for this trait were detected across environments; rice cv Kasalath had a positive allele only at one QTL on chromosome 6 (tgw6). A near-isogenic line (NILtgw6) that carried a rice cv Kasalath chromosomal segment corresponding to tgw6 in the rice cv Nipponbare genetic background was selected and analyzed to clarify the physiological function of this locus. The carbohydrate storage capacity before heading in NILtgw6 was superior to that in rice cv Nipponbare (control), but other characters (e.g. photosynthetic ability in flag leaf and traits related to plant type) were the same in both plants. In the leaf sheath, the main organ that accumulates carbohydrate before heading in rice, higher contents of carbohydrate and transcripts of genes related to starch synthesis were found in NILtgw6 than in rice cv Nipponbare. Compared with those in rice cv Nipponbare, a high-yield modern cultivar, TGW and yield per plant were significantly higher in NILtgw6, by 10% and 15%, respectively (P[f] &lt; 0.01). These results suggest that tgw6 improves the carbohydrate storage capacity and consequently increases the yield potential in NILtgw6.
Resorption Protection. Anthocyanins Facilitate Nutrient Recovery in Autumn by Shielding Leaves from Potentially Damaging Light Levels
Authors: Hoch William A. , Singsaas Eric L. , McCown Brent H. 
Published: November 2003

Abstract
The resorption protection hypothesis, which states that anthocyanins protect foliar nutrient resorption during senescence by shielding photosynthetic tissues from excess light, was tested using wild-type (WT) and anthocyanin-deficient mutants of three deciduous woody species, Cornus sericea, Vaccinium elliottii (Chapmn.), and Viburnum sargentii (Koehne). WT Betula papyrifera (Marsh) was included to compare the senescence performance of a species that does not produce anthocyanins in autumn. Plants were subjected to three environmental regimes during senescence: an outdoor treatment; a 5-d high-stress (high light and low temperature) treatment followed by transfer to a low-stress environment and a low-stress treatment that served as control. In the outdoor treatment, the appearance of anthocyanins in senescing leaves of WT plants was concomitant with the development of photo-inhibition in mutant plants of all three anthocyanin-producing species. In the high-stress environment, WT plants maintained higher photochemical efficiencies than mutants and were able to recover when transferred to the low-stress environment, whereas mutant leaves dropped while still green and displayed signs of irreversible photooxidative damage. Nitrogen resorption efficiencies and proficiencies of all mutants in both stressful treatments were significantly lower than the WT counterparts. B. papyrifera displayed photochemical efficiencies and nitrogen resorption performance comparable with the highest of the anthocyanin-producing species in all three senescing environments, indicating a photoprotective strategy divergent from the other species studied. These results strongly support the resorption protection hypothesis of anthocyanins in senescing leaves.
eEF1A Isoforms Change in Abundance and Actin-Binding Activity during Maize Endosperm Development
Authors: Lopez-Valenzuela Jose A. , Gibbon Bryan C. , Hughes Peter A. , Dreher Theo W. , Larkins Brian A. 
Published: November 2003

Abstract
Eukaryotic elongation factor 1A (eEF1A) appears to be a multifunctional protein because several biochemical activities have been described for this protein, in addition to its role in protein synthesis. In maize (Zea mays) endosperm, the synthesis of eEF1A is increased in o2 (opaque2) mutants, and its concentration is highly correlated with the protein-bound lysine content. To understand the basis of this relationship, we purified eEF1A isoforms from developing endosperm and investigated their accumulation and their functional and structural properties. Formation of three isoforms appears to be developmentally regulated and independent of the o2 mutation, although one isoform predominated in one high lysine o2 inbred. The purified proteins differ in their ability to bind F-actin in vitro, suggesting that they are functionally distinct. However, they share similar aminoacyl-tRNA-binding activities. Tandem mass spectrometry revealed that each isoform is composed of the four same gene products, which are modified posttranslationally by methylation and phosphorylation. The chemical differences that account for their different actin-binding activities could not be determined.
What Affects mRNA Levels in Leaves of Field-Grown Aspen? A Study of Developmental and Environmental Influences
Authors: Wissel Kirsten , Pettersson Fredrik , Berglund Anders , Jansson Stefan 
Published: November 2003

Abstract
We have analyzed the abundance of mRNAs expressed from 11 nuclear genes in leaves of a free-growing aspen (Populus tremula) tree throughout the growing season. We used multivariate statistics to determine the influence of environmental factors (i.e. the weather before sampling) and developmental responses to seasonal changes at the mRNA level for each of these genes. The gene encoding a germin-like protein was only expressed early in the season, whereas the other tested genes were expressed throughout the season and showed mRNA variations on a day-to-day basis. For six of the genes, reliable models were found that described the mRNA level as a function of weather, but the leaf age was also important for all genes except one encoding an early light-inducible protein (which appeared to be regulated purely by environmental factors under these conditions). The results confirmed the importance of several environmental factors previously shown to regulate the genes, but we also detected a number of less obvious factors (such as the variation in weather parameters and the weather of the previous day) that correlated with the mRNA levels of individual genes. The study shows the power of multivariate statistical methods in analyzing gene regulation under field conditions.
Multiple Hormones Act Sequentially to Mediate a Susceptible Tomato Pathogen Defense Response
Authors: O'Donnell Philip J. , Schmelz Eric , Block Anna , Miersch Otto , Wasternack Claus , Jones Jeffrey B. , Klee Harry J. 
Published: November 2003

Abstract
Phytohormones regulate plant responses to a wide range of biotic and abiotic stresses. How a limited number of hormones differentially mediate individual stress responses is not understood. We have used one such response, the compatible interaction of tomato (Lycopersicon esculentum) and Xanthomonas campestris pv vesicatoria (Xcv), to examine the interactions of jasmonic acid (JA), ethylene, and salicylic acid (SA). The role of JA was assessed using an antisense allene oxide cyclase transgenic line and the def1 mutant to suppress Xcv-induced biosynthesis of jasmonates. Xcv growth was limited in these lines as was subsequent disease symptom development. No increase in JA was detected before the onset of terminal necrosis. The lack of a detectable increase in JA may indicate that an oxylipin other than JA regulates basal resistance and symptom proliferation. Alternatively, there may be an increase in sensitivity to JA or related compounds following infection. Hormone measurements showed that the oxylipin signal must precede subsequent increases in ethylene and SA accumulation. Tomato thus actively regulates the Xcv-induced disease response via the sequential action of at least three hormones, promoting expansive cell death of its own tissue. This sequential action of jasmonate, ethylene, and SA in disease symptom development is different from the hormone interactions observed in many other plant-pathogen interactions.
Serous effusions: diagnosis of malignancy beyond cytomorphology. An analytic review
Authors: Mohanty S K , Dey P 
Published: November 2003

Abstract
In this brief review, the role of various ancillary techniques to detect malignancy in effusion fluid are evaluated and discussed. The data were collected from a large number of research articles published in various medical journals. The role of these techniques to increase the diagnostic accuracy in serous effusions is emphasised.
“Osler’s phenomenon”: misdiagnosing Cushing’s syndrome
Authors: De P , Evans L M , Scanlon M F , Davies J S 
Published: November 2003

Abstract
The clinical manifestations of Cushing’s syndrome can be quite variable and are frequently mistaken, with consequent delayed diagnosis and significant morbidity and mortality. Harvey Cushing described the typical signs and symptoms of Cushing’s syndrome but unfortunately attributed the features to myxoedema. The first typical description of a patient with Cushing’s syndrome was probably made by Sir William Osler in 1898. Thus delay or misdiagnosis with consequent high morbidity and mortality exemplifies the history of Cushing’s syndrome.
Four cases of Cushing’s syndrome are described that were associated with deteriorating morbidity because of the considerable delay from first presentation to a secondary care physician to eventual diagnosis. The clinical diagnosis was delayed in all the four patients, although they had symptoms and signs that were missed by a number of primary and secondary care physicians. Trans-sphenoidal surgery resulted in biochemical cure as well as improvement in the accompanying co-morbidity.
Although still rare, the prevalence of Cushing’s syndrome is increasing. Increasing clinical awareness and the use of appropriate screening tests should facilitate earlier diagnosis with reduced morbidity and mortality. Although the syndrome is named after Harvey Cushing, Sir William Osler was probably the first to describe it. Therefore, in deference to Osler’s contribution to Cushing’s syndrome and the work of Harvey Cushing, it is suggested that to the list of the other eponymous conditions of Osler-Weber-Rendu and Osler’s nodes, should be added the delay or misdiagnosis of Cushing’s syndrome—“Osler’s phenomenon”.
A Framework for Building Scientific Knowledge Grids Applied to Thermochemical Tables
Authors: von Laszewski Gregor , Ruscic Branko , Amin Kaizar , Wagstrom Patrick , Krishnan Sriram , Nijsure Sandeep 
Published: November 2003

An important part of enabling the future information infrastructure is to provide convenient services for application users that make such an environment highly functional and easy to use for the non-expert. In other words, the scientist should be able to focus on the science but should have sophisticated tools at hand that enable new and enhanced modalities in which science can be performed. We describe a general architecture that provides access to scientific applications. We demonstrate how such services can interact with each other and be reused by the scientific application architect to orchestrate Grid services. Our architecture is implemented by reusing concepts, infrastructures, and middleware from Web and Grid services, as well as from the newest Globus Toolkit and the Java CoG Kit. We apply our general architecture to a specific application: Active Thermochemical Tables. This application demonstrates a number of interesting and future-oriented uses, such as the need for batch processing, interactive and collaborative steering, use of multiple platforms,visualization through large displays, and access via a portal framework. Besides the innovative use of the Grid and Web services, we also provide a novel algorithmic contribution to scientific disciplines that use thermochemical tables. Specifically, we modified the original approach to constructing thermochemical tables to include an iterative process of refinement leading to increased accuracy. We have designed a variety of access environments including a shell, a Grid desktop, and a portal for accessing the set of services provided, which include the display of network dependencies between the reactions a chemist may be interested in and interactive querying of associated species data. Modalities that need to be supported are the protection of intellectual property, the creation of metadata and information shared with and gathered by the community, and easy access to the service by the application scientists.
G-CSF signaling can differentiate promyelocytes expressing a defective retinoic acid receptor: evidence for divergent pathways regulating neutrophil differentiation
Authors: Maun Noel A. , Gaines Peter , Khanna-Gupta Arati , Zibello Theresa , Enriquez Louie , Goldberg Laura , Berliner Nancy 
Published: November 2003

Abstract
Several lines of investigation suggest that granulocyte colony-stimulating factor (G-CSF) augments all-trans retinoic acid (ATRA)–induced neutrophil differentiation in acute promyelocytic leukemia (APL). We sought to characterize the relationship between G-CSF– and ATRA-mediated neutrophil differentiation. We established a G-CSF receptor-transduced promyelocytic cell line, EPRO-Gr, derived from the granulocyte-macrophage colony-stimulating factor (GM-CSF)–dependent EPRO cell line harboring a dominant-negative retinoic acid receptor alpha (RARα). In EPRO-Gr, neutrophil differentiation occurs either in GM-CSF upon addition of ATRA or upon induction with G-CSF alone. Transient transfection of EPRO-Gr cells with a RARE-containing reporter plasmid demonstrates increased activity in the presence of ATRA, but not G-CSF, while STAT3 phosphorylation occurs only in response to G-CSF. This suggests that ATRA-mediated differentiation of EPRO-Gr cells occurs via a RARE-dependent, STAT3-independent pathway, while G-CSF–mediated differentiation occurs via a RARE-independent, STAT3-dependent pathway. ATRA and G-CSF thus regulate differentiation by divergent pathways. We characterized these pathways in the APL cell line, NB4. ATRA induction of NB4 cells resulted in morphologic differentiation and up-regulation of C/EBPϵ and G-CSFR, but not in STAT3 phosphorylation. The addition of G-CSF with ATRA during NB4 induction resulted in STAT3 phosphorylation but did not enhance differentiation. These results may elucidate how G-CSF and ATRA affect the differentiation of primary and ATRA-resistant APL cells.
Mutations in the tyrosine kinase domain of FLT3 define a new molecular mechanism of acquired drug resistance to PTK inhibitors in FLT3-ITD–transformed hematopoietic cells
Authors: Bagrintseva Ksenia , Schwab Ruth , Kohl Tobias M. , Schnittger Susanne , Eichenlaub Sabine , Ellwart Joachim W. , Hiddemann Wolfgang , Spiekermann Karsten 
Published: November 2003

AbstractActivating mutations in the juxtamembrane domain (FLT3-length mutations, FLT3-LM) and in the protein tyrosine kinase domain (TKD) of FLT3 (FLT3-TKD) represent the most frequent genetic alterations in acute myeloid leukemia (AML) and define a molecular target for therapeutic interventions by protein tyrosine kinase (PTK) inhibitors. We could show that distinct activating FLT3-TKD mutations at position D835 mediate primary resistance to FLT3 PTK inhibitors in FLT3-transformed cell lines. In the presence of increasing concentrations of the FLT3 PTK inhibitor SU5614, we generated inhibitor resistant Ba/F3 FLT3-internal tandem duplication (ITD) cell lines (Ba/F3 FLT3-ITD-R1-R4) that were characterized by a 7- to 26-fold higher IC50 (concentration that inhibits 50%) to SU5614 compared with the parental ITD cells. The molecular characterization of ITD-R1-4 cells demonstrated that specific TKD mutations (D835N and Y842H) on the ITD background were acquired during selection with SU5614. Introduction of these dual ITD-TKD, but not single D835N or Y842H FLT3 mutants, in Ba/F3 cells restored the FLT3 inhibitor resistant phenotype. Our data show that preexisting or acquired mutations in the PTK domain of FLT3 can induce drug resistance to FLT3 PTK inhibitors in vitro. These findings provide a molecular basis for the evaluation of clinical resistance to FLT3 PTK inhibitors in patients with AML.
Anoxic induction of ATF-4 through HIF-1–independent pathways of protein stabilization in human cancer cells
Authors: Ameri Kurosh , Lewis Claire E. , Raida Martin , Sowter Heidi , Hai Tsonwin , Harris Adrian L. 
Published: November 2003

AbstractHypoxia is a key factor in tumor development, contributing to angiogenesis and radiotherapy resistance. Hypoxia-inducible factor-1 (HIF-1) is a major transcription factor regulating the response of cancer cells to hypoxia. However, tumors also contain areas of more severe oxygen depletion, or anoxia. Mechanisms for survival under anoxia are HIF-1α independent in Caenorhabditis elegans and, thus, differ from the hypoxic response. Here we report a differential response of cancer cells to hypoxia and anoxia by demonstrating the induction of activating transcription factor-4 (ATF-4) and growth arrest DNA damage 153 (GADD153) protein specifically in anoxia and the lack of induction in hypoxia. By applying RNAi, ATF-4 induction in anoxia was shown to be independent of HIF-1α, and desferrioxamine mesylate (DFO) and cobalt chloride induced HIF-1α but not ATF-4 or GADD153. Furthermore, the inductive response of ATF-4 and GADD153 was not related to alterations in or arrest of mitochondrial respiration and was independent of von Hippel-Lindau (VHL) disease mutations. In reoxygenated anoxic cells, ATF-4 had a half-life of less than 5 minutes; adding the proteasome inhibitor to normoxic cells up-regulated ATF-4 protein. Extracts from primary human tumors demonstrated more ATF-4 expression in tumors near necrotic areas. Thus, this study demonstrates a novel HIF-1α–independent anoxic mechanism that regulates ATF-4 induction at the protein stability level in tumor cells.
Image-guided radiovirotherapy for multiple myeloma using a recombinant measles virus expressing the thyroidal sodium iodide symporter
Authors: Dingli David , Peng Kah-Whye , Harvey Mary E. , Greipp Philip R. , O'Connor Michael K. , Cattaneo Roberto , Morris John C. , Russell Stephen J. 
Published: November 2003

AbstractThe Edmonston vaccine strain of measles virus (MV-Edm) propagates efficiently in a broad range of human tumor cells, killing them selectively. However, the oncolytic potency of MV-Edm in different human tumor xenograft therapy models is highly variable and there is no convenient way to map the distribution of virus-infected tissues in vivo. To enhance the oncolytic potency of MV-Edm against radiosensitive malignancies and to facilitate noninvasive imaging of infected tissues, we generated a recombinant MV-Edm encoding the human thyroidal iodide symporter (NIS). MV-NIS replicated almost as efficiently as unmodified MV-Edm, and human tumor cells efficiently concentrated radioiodine when infected with MV-NIS. Intratumoral spread of MV-NIS was noninvasively demonstrated by serial gamma-camera imaging of iodine-123 (123I) uptake both in MV-sensitive KAS-6/1 myeloma xenografts, which regressed completely after a single intravenous dose of MV-NIS, and in MM1 myeloma xenografts, which were unresponsive to MVNIS therapy. However, MV-resistant MM1 tumors regressed completely when 131I was administered 9 days after a single intravenous injection of MV-NIS (radiovirotherapy). 131I alone had no effect on MM1 tumor growth. While the potential hematopoietic toxicity of this new therapy requires further evaluation, image-guided radiovirotherapy is a promising new approach to the treatment of multiple myeloma, an incurable but highly radiosensitive plasma cell malignancy. Testing in other radiosensitive cancers is warranted.