Transforming growth factor beta 1 (TGFB1) is a cytokine involved in the development of both acute and late cutaneous radiation syndromes. We previously demonstrated that ionizing radiation induces TGFB1 expression in ...
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Transforming growth factor beta 1 (TGFB1) is a cytokine involved in the development of both acute and late cutaneous radiation syndromes. We previously demonstrated that ionizing radiation induces TGFB1 expression in vivo in pig skin within a few hours. The purpose of the present study was to develop an in vitro human model to identify the mechanisms of this early activation. Accordingly, human HaCaT keratinocytes were irradiated with a single dose of 20 Gy. First, radiation-induced TGFB1 overexpression was checked at both the transcriptional and transductional levels in HaCaT cells. Then electrophoretic mobility shift assays (EMSA) and transient transfection with various TGFB1 promoter constructs were used to identify the sequences involved in regulating this promoter. ENISA analysis showed the induction of nuclear protein binding activity by T irradiation to the -365 AP1 sequence (TGTCTCA), suggesting the involvement of AP1 sequences in the regulation of TGFBI transcription. In gene reporter assays, maximal TGFBI promoter activation was found for the longest construct, which contains two AP1 sequences. However, assays with constructs including deletions showed that these two AP1 sequences were not sufficient to confer TGFBI inducibility. These results showed for the first time, to our knowledge, that transcriptional regulation is involved in radiation-induced activation of TGFB1 gene expression. (C) 2002 by Radiation Research Society.
PAUL DUNDASHARIBHADRA ON GIVINGThe role of giving as a basic level category of action which, like language, is learned early in human cognitive development and subsequently comes to occupy a fundamental role in experi...
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PAUL DUNDASHARIBHADRA ON GIVINGThe role of giving as a basic level category of action which, like language, is learned early in human cognitive development and subsequently comes to occupy a fundamental role in experience and civilisation is indisputable.1 Yet, as with language, such a basic behavioural trait can hardly be anticipated to be free from *** is likely that most individuals would acknowledge that there is more to giving than mere transaction and perhaps concur with some variation of the observation provided by that supreme recorder of bourgeois platitudes, Flaubert, according to whose Dictionnaire des Id ees Recues Le cadeau nest rien, cest lintention.2 Scholarship in the social sciences, it is gratifying to record, also accepts that there is more toa gift than meets the eye and, since the first publication seventy five years ago of Marcell Mausss Essai sur le Don,3 it has been repeatedly confirmed that what is truly significant about giving and receiving is not the gift itself but the social relation which exchange *** recently, gift giving has come to be discussed in the light of Derridas claim that an understanding of the nature of the gift can only be gained if it is somehow removed from the circle of exchange.
In response to a request by the Buddha that he be visited and cheered up, a succession of the Buddhist establishments great and good describes how, in the course of previous encounters with Vimalakrti, the bodhisattva had discomfited them in almost burlesque fashion by demonstrating the ontologically treacherous ground upon which the basic institutions and attitudes of Buddhism were based.
[...]on meeting the arhat Mahakasyapa who had embarked on the apparently innocuous enterprise of searching for alms, Vimalakrti had demonstrated to that great ascetic disciple of the Buddha that for the one who understands the true nature of reality, the only way in which to accept food from a layperson is by not taking anything at a
Virtual Home Environments (VHE) is the concept that networks supporting mobile users should provide them with the same computing environment on the road as they are used to having in their home or corporate computing ...
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P elements from two P-tagged alleles, stm A(P1) and stm A(P4), of the temperature-sensitive paralytic mutant stambh A (stm A) were remobilized to derive wild-type revertants and P excision lethals. stm Apt remutated t...
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P elements from two P-tagged alleles, stm A(P1) and stm A(P4), of the temperature-sensitive paralytic mutant stambh A (stm A) were remobilized to derive wild-type revertants and P excision lethals. stm Apt remutated to lethality, while stm A(P4) reverted to the wild type. The P excision lethals are not amorphic mutations, since they were weaker in paralytic phenotype (i) than the parental P-tagged allele and (ii) for deficiencies for stm A. The lethals collectively affected all stages of the life cycle, demonstrating that stm A(+) is needed throughout fly development.
A significant improvement in the relationship between Iran and the US, with vital implications for the Middle East, is likely to occur during US President George Bush Jr's term in office. A breakthrough in relatio...
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A significant improvement in the relationship between Iran and the US, with vital implications for the Middle East, is likely to occur during US President George Bush Jr's term in office. A breakthrough in relations with Washington will mean increased strategic leverage as a major transit route for oil and gas exports from Central Asia and an enhanced status in the region. Iran has the capacity to produce more than 4 million b/d of crude oil and is sustainable for long period. A more effective containment of the Taliban regime in Afghanistan is virtually assured if the US-Iran relations improve.
With the rapid drilling of deep wells, cementing operations encounter new and more complex challenges due to harsh environments. To improve the use and selection of CaO-type expanding cements, a series of measurements...
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With the rapid drilling of deep wells, cementing operations encounter new and more complex challenges due to harsh environments. To improve the use and selection of CaO-type expanding cements, a series of measurements have been made. Calcium oxide is used as an expanding agent to overcome contraction as cement slurry sets. Cement systems selection was based on their performances indicated by expansion tendency, consistency behaviour, lime reactivity at 60degreesC and atmospheric pressure. and autoclave-cured cement paste properties. Slurries were prepared using different mixing methods (API standards and an in-house procedure) to help choose appropriate slurry designs for wide field applications. Expansion and consistency tests were carried out in High Pressure-High Temperature devices at 60, M 90 and 120degreesC and 120 MPa. Mix waters of different salinities and sulphur contents were used to prepare cement slurries. It is shown that the expanding influence of CaO becomes significant when the temperature is higher than 60degreesC, but less than 80degreesC;salt content of 20-30 % by weight of water;lime concentration of 12.5%, Gel and shear strengths of 150 Pa and 4 MPa, respectively and cement expansion greater than 4 % give sufficient tightness and seal, to stop gas migration in boreholes.
Understanding mechanisms that regulate when, where and how flowers are formed would elucidate cell-fate determination in plants. Some of the advances made towards deciphering genes controlling floral induction, merist...
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Understanding mechanisms that regulate when, where and how flowers are formed would elucidate cell-fate determination in plants. Some of the advances made towards deciphering genes controlling floral induction, meristem specification and floral organ patterning are reviewed here. Studies beginning in the early 1980s of mutations in Arabidopsis thaliana of Antirrhinum majus that alter either floral induction or floral meristem fate or floral organ fate were start points for these analyses. Cloning and functional characterization of the corresponding genes has illustrated how transcription factors of the MADS box gene-family or factors involved in cell-cell signalling regulate cell fate. These studies reveal evolutionarily conserved elements in the flower development pathway.
The host specificity of yeast-yeast interactions was investigated for two yeast types, represented by six pairs of Pichia membranifaciens clade yeasts (Pichia membranifaciens or Issatchenkia occidentalis) with apicula...
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The host specificity of yeast-yeast interactions was investigated for two yeast types, represented by six pairs of Pichia membranifaciens clade yeasts (Pichia membranifaciens or Issatchenkia occidentalis) with apiculate yeasts (Kloeckera apis, Kloeckera africana, or Saccharomycodes ludwigii), commonly found in fruits. Competitive interactions between the two types were detected in both ripe tomato and guava. fruit pulp. The differences in growth rates and carrying capacities depended on fruit type (host) and culture conditions (monocultures versus bicultures). These differences were probably due to nutrient composition of each fruit. Pichia membranifaciens did not show host dependent responses, but the apiculate yeasts and Issatchenkia occidentalis did. Depending on yeast strain and culture conditions (i.e., monoculture or biculture), carbon, nitrogen, and vitamins were investigated as potential limiting growth factors in guava fruit. Both singular and multiple limiting nutrients were implicated.
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