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Span shortening

The life span of the normal red blood cell is 120 days this means that slightly less than 1% of the population of red cells (200 billion cells, or 2 million per second) is replaced daily. The new red cells that appear in the circulation still contain ribosomes and elements of the endoplasmic reticulum. The RNA of the ribosomes can be detected by suitable stains (such as cresyl blue), and cells containing it are termed reticulocytes they normally number about 1% of the total red blood cell count. The life span of the red blood cell can be dramatically shortened in a variety of hemolytic anemias. The number of reticulocytes is markedly increased in these conditions, as the bone marrow attempts to compensate for rapid breakdown of red blood cells by increasing the amount of new, young red cells in the circulation. [Pg.609]

No data were found on the effects of silver compounds on avian or mammalian wildlife. All controlled studies with silver were with domestic poultry, livestock, or small laboratory mammals. Signs of chronic silver ion intoxication in tested birds and mammals included cardiac enlargement, vascular hypertension, hepatic necrosis, anemia, lowered immunological activity, altered membrane permeability, kidney pathology, enzyme inhibition, growth retardation, and a shortened life span (Smith and Carson 1977 Freeman 1979 Fowler and Nordberg 1986 USPHS 1990). [Pg.565]

Zinc deficiency places an increased demand on selenium (Se) pools in daphnids. As little as 5 pg Se/L in zinc-free water eliminated overt cuticle damage and substantially increased reproduction, but did not alter the shortened life span. Cladocerans at the threshold of Se deficiency will become overtly Se deficient when zinc supplies are lacking (Keating and Caffrey 1989). Insufficient copper introduces cuticle problems in daphnids similar to those introduced by insufficient zinc or... [Pg.645]

B19. Brewer, G. J., Tarlov, A. R., and Kellermeyer, R. W., The hemolytic effect of primaquine. XII. Shortened erythrocyte life span in primaquine sensitive male Negroes in the absence of drug administration. J. Lab. Clin. Med. 58, 217-224 (1961). [Pg.298]

Toxicologists nowadays take a broad view of developmental toxicity they consider not only structural but also functional abnormalities to qualify as adverse, as long as they were produced as a result of exposures incurred in utero. Thus, for example, the developmental effects of chronic alcohol abuse by pregnant women, known as fetal alcohol syndrome (FAS), are characterized not only by the presence of certain craniofacial abnormalities, but also by a variety of disabilities such as shortened attention span, speech disorders, and restlessness. Although fully expressed physical deformities included in FAS are associated with heavy drinking, debate continues on the level of alcohol consumption, if any, that is without these more subtle effects on behavior. [Pg.132]

Developmental toxicity, defined in its widest sense to include any adverse effect on normal development either before or after birth, has become of increasing concern in recent years. Developmental toxicity can result from exposure of either parent prior to conception, from exposure of the embryo or fetus in utero or from exposure of the progeny after birth. Adverse developmental effects may be detected at any point in the life span of the organism. In addition to stmcmral abnormalities, examples of manifestations of developmental toxicity include fetal loss, altered growth, functional defects, latent onset of adult disease, early reproductive senescence, and shortened life span (WHO/IPCS 2001b). [Pg.179]

Simple CWP often occurs concomitantly with chronic bronchitis and emphysema. Although CWP is associated with several respiratory impairments, it is not associated with shortened life span the importance of this benign condition is the fact that it is a precursor of progressive massive fibrosis (PMF). However, simple CWP does not progress in the absence of further exposure. [Pg.177]

In short, a good food, one that is a source of desirable organics and useful calories (25). limits growth and shortens life span in proportion to its presence—this presents the appearance of allelochemistry however, it is the exaggeration of a deficiency which proportionally increases. It is not the production of some allelochemical substance that proportionally increases. Like it or not, in aquatic systems the interplay of allelochemistry and nutrition can not be ignored. [Pg.143]

Whether there is any other connection between anticonvulsant activity and camosine s antiaging actions is obviously highly speculative. It may be relevant to note that epileptic seizures and a shortened life span, together with altered protein accumulation, are consequences of PIMT-deficiency in mice, while treatment with valproic acid, an anticonvulsant, partially suppresses these symptoms including effects on life span (Yamamoto et ah, 1998). Conversely, PIMT overexpression can increase life span of Drosophila (Bennet et ah, 2003). Furthermore, the chemistry of some anticonvulsants (ethosuximide) resembles quite closely the structure of the succinimide intermediate formed during both asparagine deamidation and PIMT-mediated repair of isoaspartate residues. One conjectures whether there are any relationships between these... [Pg.102]

Nocturnal plasma cortisol levels increase earlier (i.e., HPA activity is active at night and time span between sleep onset and cortisol secretion nadir is shortened ... [Pg.15]


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