Werner syndrome: a molecular genetic hypothesis
Article Abstract:
Werner syndrome (WS) is an autosomal recessive genetic disorder that causes premature aging, with afflicted persons dying as young as 31 and living as long as 63. The average age at death is 47. Although the average age at diagnosis is 38, many signs and symptoms occur much earlier, especially cessation of growth, beginning around age 13. Typically, the clinical signs include premature atherosclerosis (hardening of the arteries), cancers, osteoporosis, diabetes, and cataracts. These authors hypothesize that the primary genetic abnormality is in a regulatory gene that should encode a factor that represses a second genetic site or its protein product that inhibits DNA synthesis when cells reach the end of the replicative (reproducing) life span. When the genetic abnormality occurs, it results in an accumulation of the inhibitor of DNA synthesis (IDS), DNA synthesis is repressed and thus cells do not reproduce themselves. The authors note that while their hypothesis is speculative, the model they propose is supported by the majority of clinical and experimental observations in WS. Work continues to isolate repressor and IDS gene sequences and it is suggested that the current hypothesis lays the groundwork for further studies. (Consumer Summary produced by Reliance Medical Information, Inc.)
Publication Name: Journals of Gerontology
Subject: Seniors
ISSN: 0022-1422
Year: 1990
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Collapse and growth
Article Abstract:
Collapse of more open and chaotic carbon clusters into fullerenes is the manner by which buckminsterfullerene is synthesized effectively. Two schemes were developed to come up with buckminsterfullerene, the pentagon-road and the fullerene-road, but the field is receptive to novel descriptions of fullerene formation. The viability can be examined by the dependence of ion structures' collapse into fullerenes based on size and ion energy. Detonation temperature must be estimated and composition compared with simulations.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1993
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Insist on consistency
Article Abstract:
A British Standard in educational qualifications should be developed by the government in order to protect against harmful criticism that some qualifications are intellectually inferior to others. Vocational qualifications are perceived to have variable standard levels, while the quality of modular Advanced level examinations is coming under particular scrutiny. Codes of practice and award frameworks were introduced at the end of the 1980s, but different types of qualifications should not be treated similarly.
Publication Name: Times Higher Education Supplement
Subject: Education
ISSN: 0049-3929
Year: 1997
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