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Biomedical subjects

B White

Publications and source records attributed to B White.

At least 181 records · Page 10Linked to original sources
PubMed1983

Facial asymmetry in posed and spontaneous expressions of emotion.

Patterns of facial asymmetry (i.e., extent of movement) as a function of elicitation condition, emotional valence, and sex of subjects are examined. Thirty-seven right-handed adult males and females were videotaped making positive and negative expressions of emotion under posed (verbal, visual) and spontaneous conditions. There were no differences in facial asymmetry as a function of condition. Overall, expressions were significantly left-sided, a finding implicating the right hemisphere. When sex and valence were considered, negative expressions were left-sided for all subjects, while positive expressions were left-sided for males only. Further, positive expressions were significantly less lateralized than negative ones for females. Measures of hemiface mobility and ocular dominance did not mediate these patterns of facial lateralization.

Adult↗
PubMed1983

Asymmetries in body part size, mobility, and usage. Relationship between structure and function.

Asymmetries in structure (size) and function (usage or mobility) for the upper and lower face, hands, and feet were investigated in 42 left- and right-handed male and female college students. Size measurements were taken from photographs, mobility was rated from videotapes, and usage was assessed by questionnaire. Size asymmetries were typical, and independent of handedness, but were not consistent across body parts; usage asymmetries varied as a function of handedness. No systematic relationships were found between structure and function.

Adolescent↗
PubMed1983

Is there a bias in size measurements taken from mirror-reversed photographs of body parts?

This study compared measurements of hands, feet, and hemifaces taken from original and mirror-reversed photographs to determine whether a hemispace-bias exists in size measurements. Posers were adult right- and left-handers (50% female). In 80% of the measurement comparisons (total N = 84), there was complete agreement; there were no instances of right-left reversals among the discrepant comparisons. The side of the body measured as larger was independent of the side of space in which it appeared. The lack of such bias in physical measurements is discrepant with data suggesting a left-hemispace preference in psychological judgments of visual material.

Adult↗
PubMed1982

Comparison of red cell and kidney (Na+ +K+)-ATPase at 0 degrees C.

Human red cell and guinea pig kidney (Na+ +K+)-ATPase were phosphorylated at 0 degrees C. Using concentrations of ATP ranging from 10(-6) to 10(-8) M, ATP-dependent regulation of reactivity is observed with red cell but not kidney (Na+ +K+)-ATPase at 0 degrees C. In particular, with the red cell enzyme only, the following are observed: (i) the ratio of enzyme-bound ATP (E.ATP, measured by the pulse-chase method of Post, R.L., Kume, S., Tobin, T., Orcutt, B. and Sen, A.K. (1969) J. Gen. Physiol. 54, 306s-326s) to steady-state level of total phosphoenzyme (EP) decreases with decrease in ATP concentration and (ii) the apparent turnover of phosphoenzyme (ratio of Na+-stimulated ATP hydrolysis to level of total EP at steady state) also varies as a function of ATP concentration. In addition, when EP is formed at very low ATP (0.02 microM), and then EDTA is added, rapid disappearance of a fraction of EP occurs, presumably due to ATP resynthesis, only with the red cell enzyme. These differences in behaviour of the red cell and kidney enzymes are explained on the basis of the observed predominance of K+-insensitive EP in red cell, but K+-sensitive EP in kidney (Na+ +K+)-ATPase at 0 degrees C.

Animals↗
PubMed1981

Legislation.

Explore the source record for details and available documents.

Florida↗
PubMed1978

Differences and changes in VO2 among young runners 10 to 18 years of age.

Twenty young males, all active in middle-distance running, were studied between January 1968 and May 1974 for the purpose of gathering longitudinal data regarding Vo2 during treadmil running. Vo2 submax (measured during the last 2 min of a 6-min run at 202 m/min) and Vo2 max values (measured during a 5-8 min increasing-speed run to exhaustion) were collected approximately every 6 months for 6 years. Different groups, starting at ages of 10, 12 and 13 years were followed for periods of 2 to 5 years continuously. In all longitudinal comparisons. Vo2 max (ml/min) changes peralleled changes in body weight; consequently, Vo2 max (ml/kg.min-1) did not show a significant change. In every group Vo2 submax (ml/kg.min-1) dropped significantly over time. All data were pooled by 1 yr age groups, providing cross-sectional data for active boys 10-18 yrs of age. Vo2 max ranged from 1933 ml/min for 10-yr olds to 4082 for 18-year olds. Concurrent changes in weight resulted in no significant differences in Vo2 max (ml/kg.min-1) from the overall mean of 61.5 Vo2 submax (ml/kg.min-1) was highest among 10-year olds (53.3) and lowest among 18-yr olds (42.5). Based on these longitudinal and cross sectional findings and significant improvements in times for 1- and 2-mile races, it was concluded that Vo2 max (ml/min) increases no faster than does body weight among moderately active growing boys and that both age and training contribute to a change in Vo2 submax; a factor which accounts greatly for improvements in middle-distance race performance.

Adolescent↗
PubMed1976

Ribulose biophosphate carboxylase from Thiobacillus A2. Its purification and properties.

Ribulose bisphosphate carboxylase (EC 4.1.1.39) from Thiobacillus A2 has been purified to homogeneity on the basis of polyacrylamide gel electrophoresis and U.V. analysis during sedimentation velocity studies. The enzyme had an optimum pH of about 8.2 with Tris-HCl buffers. The molecular weight was about 521000 with an Srel. of 16.9. Km for RuBP was 122 muM, for total "CO2" it was 4.17 mM, and for Mg2+ 20.0 muM. The absolute requirement for a divalent cation was satisfied by Mg2+ which was replaceable to a certain extent by Mn2+. Activity was not significantly affected by SO(2-4), SO(2-3), or S(2)O(2-3) at 1.0 mM. At this concentration S(2-) caused a 27% stimulation. All mercurials tested were inhibitory. pHMB was the most potent causing about 60% inhibition at 0.04 mM. This inhibition was reversible by low concentrations of cysteine. Cyanide was also inhibitory. Its mode of inhibition with respect to RuBP was un-competitive and with a Ki of 20 muM. Lost activity could be restored partially by GSH or Cu2+. Although azide at the concentration tested had no significant effect on enzyme activity, 2, 4-dinitrophenol at 1.0 mM caused 91% inhibition. Finally, activity was also affected by energy charge.

Adenine Nucleotides↗
PubMed1976

Physical properties and metabolite regulation of ribulose bisphosphate carboxylase from Thiobacillus A2.

Purified ribulose-bisphosphate carboxylase (EC 4.1.1.39) was strongly and equally inhibited either by ADP or GDP and to a lesser extent by IDP. AMP or ATP exerted little effect on activity. Inhibition by the nucleotide diphosphates was competitive with respect to RuBP and non-competitive with respect to "CO2" and Mg2+, respectively. Treatment of the enzyme with urea or guanidine-HCl resulted in rapid loss of activity that was not restored by dialysis even in the presence of Mg2+ and cysteine. Sodium dodecyl sulfate electrophoresis of 8.0 M urea treated enzyme revealed the presence of a fast-moving (small) sub-unit with molecular weight 14150 and a slower moving (large) sub-unit with molecular weight 68000. Examination of native enzyme by sodium dodecyl sulfate electrophoresis gave sub-units of 13700 and 55500 respectively. The amino acid content standardized to phenylalanine was essentially similar to that from other sources. Arrhenius plots showed a "break" at 29 degrees C with an Ea of 12.34 kcal per mole for the steeper part of the curve and a deltaH of 11.43 kcal per mole while for the less steep region, the Ea was 1.04 kcal per mole and the deltaH 1.92 kcal per mole.

Amino Acids↗