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Biomedical subjects

W A Daniel

Publications and source records attributed to W A Daniel.

At least 37 records · Page 2Linked to original sources
PubMed1985

Iron status of adolescent female athletes.

To determine whether or not adolescent female athletes were more in need of routine dietary iron supplements than their nonathlete peers, the iron status of 32 athletes and 31 nonathletes was assessed. The athletes were track-team members in the middle of their season. Hemoglobin, transferrin saturation, and serum ferritin were evaluated, as well as the amount of dietary iron intake. Athletes had significantly lower serum ferritin levels and transferrin saturation (less than 16%) than did nonathletes. Black girls were significantly lower than whites on all three values. There were also a greater number of black girls deficient in serum ferritin. We conclude that athletes may be at greater risk for iron deficiency and, therefore, for iron deficiency anemia; and black adolescents may have an increased prevalence of iron deficiency, with black female athletes being at potentially greater risk for iron deficiency and its possible consequences. We recommend a more sensitive assessment of iron status in female athletes.

Adolescent↗
PubMed1985

Growth at adolescence. Clinical correlates.

Several highly significant changes occur within a relatively short period of time during adolescence. Great alteration in physique, developmental progress in thinking, and psychologic gains toward attaining ego identity take place but not always synchronously. Attention is paid to physical changes because they are visible and are of intense concern to adolescents, but physicians and other professionals should remember cognitive and psychosocial growth are affected by physical growth, and vice versa. Often there is a temporary disequilibrium in the relationship of these three areas of growth, and this can affect one or another part of the developmental pattern. It is therefore necessary to remind ourselves of the diversity of adolescent growth, and of adolescents, when caring for a young patient and be cognizant of growth in areas other than physical. More and more children with congenital or acquired handicaps are living to become adolescents and perhaps adults. Handicaps can be limited to one of the three major areas of growth or involve them all in varying degrees. For example, sickle cell disease, Crohn's disease, or ulcerative colitis may postpone physical growth for a significant period; this lack of pubertal change can affect psychosocial development but usually does not impair cognitive growth. Mental retardation may have no apparent effect on physical growth but can handicap the adolescent's psychosocial development. Growth still occurs in a sequential pattern but often it seems that handicapped youngsters reach a developmental milestone by a series of "detours." Physicians must recognize these lags or differences and try to facilitate progress, promote self-esteem, and provide understanding. Much can be done with anticipatory guidance. Adolescence often provides the opportunity to overcome past damage or, in some instances, to start anew on a more optimal program for physical and psychosocial growth. Young adolescent boys and girls usually look to the physician for factual information and guidance; they long for understanding by an adult outside of the family. If we can successfully fill their expectations, adolescents will be the better for it.

Adolescent↗
PubMed1983

A comparison of knobby (K+) and knobless (K-) parasites from two strains of Plasmodium falciparum.

Erythrocytes infected with Plasmodium falciparum develop knob-like protrusions on their membranes. Knobby (K+) parasites of the FCR-3 (Gambian) strain have been shown to possess a histidine-labelled protein of apparent molecular weight 80 000 which is absent from knobless (K-) variants of the same strain. Here we report similar findings with K+ and K- parasites of another strain, the Malayan Camp strain, and also with cloned K+ and K- parasites of the FCR-3 strain. A histidine-labelled protein unique to the two K+ parasites was identified as a broad band with an apparent molecular weight of 89 000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The presence of this protein in both K+ Malayan Camp parasites and K+ FCR-3 (Gambian) parasites and its absence from K- parasites of both strains is consistent with this protein being a major component of knobs.

Animals↗
PubMed1980

Tritrichomonas muris in the hamster: pseudocysts and the infection of newborn.

Female golden hamsters, either in the last week of pregnancy or in the first weeks of nursing, excreted in their feces variable numbers of pseudocysts of Tritrichomonas muris. Pseudocysts examined by electron microscopy had internalization of the 3 anterior flagella and the undulating membrane with its recurrent flagellum. The undulating membrane and the associated marginal lamellae were characteristic of T. muris. Pseudocysts gradually become motile after 2 or more hours of incubation in medium. The "excysted" trophozoites were identified ultrastructurally as T. muris. Newborn hamsters were not infected with T. muris at 3 days of age, but by the 7th day essentially all were found to have infected ceca, concomitant with cecal enlargement and the appearance of adult-type feces.

Animals↗