This article is the first of two reporting research concerned with the profile of degree level qualifications of initial teacher trainees who start Postgraduate Certificate of Education (PGCE) ...Secondary English courses. In a context where there is no existing database of such information, the researchers sought to establish the patterns in this profile and collate a summary of-Initial Teacher Education (ITE) tutors' perceptions about the level of subject knowledge preparedness of students with different degree level qualifications. Following from this, the enquiry was also interested in the ways that PGCE institutions support students with different subject knowledge development needs. The article that follows below treats the issue of degree qualifications and the PGCE selection process in the context of recent changes to subject English. The evidence suggests patterned but divergent practices with an overall trend of preference for prior qualifications in English Literature despite significant alterations in the study of English since 1980. PGCE courses surveyed attract many more applicants than there were places and tutors exercise considerable discretion in admissions practices which are not always made transparent by published policies and rationales, including those made available to prospective applicants. The review of the literature showed little published discourse on this topic to date.
The chromosomal ends of Trypanosoma brucei , like those of most eukaryotes, contain conserved 5â²-TTAGGG-3â² repeated sequences and are maintained by the action of telomerase.
Fractionated T. ...brucei cell extracts with telomerase activity were used as a source of potential regulatory factors or telomerase-associated components
that might interact with T. brucei telomeres. Electrophoretic mobility shift assays and UV cross-linking were used to detect possible single-stranded telomeric
protein·DNA complexes and to estimate the approximate size of the protein constituents. Three single-stranded telomeric protein·DNA
complexes were observed. Complex C3 was highly specific for the G-strand telomeric repeat sequence and shares biochemical
characteristics with G-rich, single-stranded telomeric binding proteins and with components of the telomerase holoenzyme described
in yeast, ciliates, and humans. Susceptibility to RNase A or chemical nuclease (hydroxyl radical) pre-treatment showed that
complex C3 was tightly associated with an RNA component. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry
was used to estimate the molecular mass of the peptides obtained by in-gel Lys-C digestion of low abundance C3-associated
proteins. The molecular masses of the peptides showed no homologies with other proteins from trypanosomes or with any protein
in the data bases screened.
Amphotericin B is an important agent for the treatment of invasive fungal infections in immunocompromised patients because of its broad spectrum. However, its toxicities and the availability of ...alternative agents limit its application. Lipid-based formulations of amphotericin B, such as amphotericin B lipid complex (ABLC) and liposomal amphotericin B (L-AMB), are less nephrotoxic and as effective as conventional amphotericin B. However, because of their similarities, choosing between the two formulations remains a challenge. The majority of prospective and retrospective comparative studies have shown equivalence in terms of efficacy although some subset analyses favor ABLC over L-AMB. While both drugs penetrate well in the reticuloendothelial system, ABLC gets concentrated in the lungs to a much greater extent. This may have clinical implications because the lungs are the commonest site of invasive fungal infections. L-AMB is associated with less infusion-related adverse effects and less nephrotoxicity than ABLC. ABLC has been shown to be more cost-effective than L-AMB, although this is affected by variable institutional contracts and pricing. The choice between the two drugs should be based upon due consideration of all these factors.
We have examined the effects of removing individual template nucleosides on promoter escape by Escherichia coli RNA polymerase in vitro. The ability of DNA templates containing random single ...nucleoside gaps generated by hydroxyl radical treatment to support the production of stable ternary transcription complexes was analyzed. On two templates containing different promoter and initial transcribed regions, we found that removal of nucleosides on the template strand in the region from −13 to at least +8 relative to the transcription start site interfered with ternary complex formation. The downstream border of this region varied for the two templates, suggesting an effect of the specific nucleotide sequence on the stability of intermediates in the promoter escape process. On the nontemplate strand, removal of nucleosides in the vicinity of the −10 consensus promoter element interfered with escape, whereas removal of nucleosides in the vicinity of the transcription start site actually enhanced the yield of ternary complexes. On one template, removal of nucleosides in an A-tract containing region upstream of the promoter caused a significant decrease in promoter escape, consistent with previous suggestions that contacts between this region and the RNA polymerase play a role in promoter binding and/or initiation.
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