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J Langmore

Publications and source records attributed to J Langmore.

7 recordsLinked to original sources
PubMed2001

Globalisation and social policy.

This paper discusses six major themes: that economic and social issues are closely interdependent and that the appropriate stance is to work on both together, simultaneously; that though the threats from globalisation have been exaggerated, there can be substantial costs as well as considerable benefits; that constraints on national policy are significant but are less severe than is commonly considered; that the vitality-the vigour-of national and international political processes must be increased to cope effectively with the changes which are underway; that the private sector, unions and civil society have crucial roles in the provision of services and in advocating socially responsible values, standards and policies; and that one of the most effective means of addressing the erosion of national autonomy from globalisation is for countries to cooperate in setting and implementing shared objectives and international standards and establishing more global public goods.

Commerce↗
PubMed1997

Turnover of histone acetyl groups during sea urchin early development is not required for histone, heat shock and actin gene transcription.

Histone acetylation is an extremely complex, reversible and specific process. In order to evaluate the importance of this modification for gene expression during sea urchin development, acetyl group turnover of histone lysine residues was blocked by sodium butyrate. The continuous presence of 15 Mm sodium butyrate in the incubation medium from the onset of development blocked gastrulation and resulted in chromatin containing hyperacetylated histone molecules in amounts usually not found in nature. At the mesenchyme blastula stage, the expression of the early histone genes was shut off and the expression of the late genes was switched on both in control and sodium butyrate-treated embryos. Investigation of the early histone gene chromatin structure in butyrate-treated embryos revealed a random distribution of nucleosomes when the genes were transcriptionally active as compared to regular nucleosomal packaging when genes were inactive. These changes in chromatin structure during development mimicked the chromatin structural transition of the early histone genes in control embryos. In addition, the ability of heat shock genes to be induced at elevated temperature and repressed at normal temperature was unaffected in butyrate treatment of embryos. Finally, the developmental profiles of the cytoskeletal CyIIIa actin gene expression in control and butyrate-treated embryos were very similar. The data presented suggest that turnover of histone acetyl groups and the overall level of histone acetylation are not determining factors in the up and down regulation of a number of genes during early development of sea urchin.

Acetylation↗
PubMed1992

c-myb effects on kinetic events during MEL cell differentiation.

During dimethylsulfoxide (DMSO)-induced differentiation of Friend mouse erythroleukemia (MEL) cells there is a biphasic fall in c-myb mRNA levels. We have previously shown that constitutive expression of c-myb blocks differentiation. To delineate more accurately the point at which Myb blocks differentiation, MEL cells were transfected with a human c-myb construct under the control of the beta-globin promoter and enhancers. In concert with endogenous DMSO-induced globin transcription during MEL cell differentiation, the beta-globin c-myb transcription unit of the transfected plasmid is activated after 3-5 days of culture in media containing DMSO. Here we describe c-myb-transformed MEL clones which undergo delayed expression of the exogenous c-myb following 3-5 days of culture in DMSO. In contrast to wild-type MEL cells, both clones failed to display phenotypic markers of differentiation and continued to proliferate for up to 10 days of culture. These data suggest that the late fall in c-myb levels may be required in order for differentiation to occur. Additionally, we suggest that constitutive expression of c-myb does not block early commitment events such as activation of histone Hl', subsequent chromatin condensation, and alteration of proliferation-related gene expression. Taken together, these results show that c-myb acts very late in the process of differentiation.

Animals↗
PubMed1974

Scanning transmission electron microscopy at high resolution.

We have shown that a scanning transmission electron microscope with a high brightness field emission source is capable of obtaining better than 3 A resolution using 30 to 40 keV electrons. Elastic dark field images of single atoms of uranium and mercury are shown which demonstrate this fact as determined by a modified Rayleigh criterion. Point-to-point micrograph resolution between 2.5 and 3.0 A is found in dark field images of micro-crystallites of uranium and thorium compounds. Furthermore, adequate contrast is available to observe single atoms as light as silver.

Crystallography↗