A System for Evaluating and Treating Chronic Back Disability

Five methods of personality assessment are evaluated to provide guidance for the psychological treatment of patients with chronic back pain. Patient pain drawings, pentothal pain studies, stress score index, psychological testing with the Minnesota Multiphasic Personality Inventory (MMPI) and response to treatment challenge are used as measurements for evaluation. This evaluation gives the treating staff guidelines for individual treatment programs utilizing operant conditioning techniques. Using this approach, three fourths of the severely disabled patients seen have been successfully treated.     

Spermatogenesis in an infertile XYY man

Summary Testicular histology and meiosis has been studied in an XYY male patient identified at an infertility clinic. This man was found to have an XYY sex chromosome complement in 15% of spermatogonial metaphases. There was no clear evidence of 2 Y chromosomes at diakinesis but there appeared to be a slight excess of sperm with a fluorescent Y body.     

Cytochemical evidence of extramembranous carbohydrates on Ureaplasma urealyticum (T-strain Mycoplasma).

Cells of Ureaplasma urealyticum that were prepared by a ruthenium red technique demonstrated an extramembranous layer of polyanions of about 15 to 30 nm in width. Application of the concanavalin A-iron dextran strain indicated that the outer surface of this layer contained glucosyl-like residues.     

Variation in sex ratio between progeny groups in dairy cattle

Summary Highly significant differences between progeny groups have been found in the Israeli-Frisian breed of cattle. The standard deviations between groups in the proportion of males was estimated to be 1.5%. Significant correlations between sire and son and between half-sibs in the sex ratio of their progeny suggest that the differences may have a genetic basis.     

On describing microbial growth kinetics from continuous culture data: Some general considerations,observations, and concepts

Analysis of continuous culture methodology suggests that this potentially powerful tool for kinetic analysis can be improved by minimizing several inherent shortcomings. Medium background substrates — organic carbon, phosphate, and manganese — were shown to dominate kinetic observations at concentrations below chemical detection methods. Reactor wall growth, culture size distribution changes, sample removal-induced steady state perturbations, and limiting substrate leakage from organisms are treated in terms of kinetic measurement errors. Large variations in maximal growth rates and substrate uptake rates found are attributed to experimental protocol-induced transient states. Relationships are presented for correcting limiting substrate concentrations for lability during sampling, contamination with unreacted medium, and background substrate effects. Analytical procedures are discussed for improved measurement of limiting substrate kinetics involving enzymes, isotopes, and material balance manipulation. Relaxation methods as applied to continuous culture are introduced as a means for isolating separate rate constants describing net substrate transport and for evaluating cellular metabolite leakage. Low velocity growth, multiple substrate metabolism, and endogenous metabolism are discussed along with measurements showing that 1-month generation times for aquatic microorganisms can be quite normal and that the kinetics are compatible withμg/liter limiting substrate concentrations. The concept of regarding growth kinetics as the sum of several net accumulation processes is suggested.     

Calcium transport in diluted or cooled ram semen

Ram semen was subjected to various dilution rates and temperatures of dilution, and was also subjected to slow cooling and rewarming. Calcium ion movements across sperm membranes were measured using the radioisotope 45Ca2+. It was shown that even 2- to 4-fold dilution caused an increase in intracellular calcium content. An increase in intracellular calcium also occurred in proportion to a decreased temperature of dilution. After an initial increase in intracellular calcium content, spermatozoa appeared able to restore a low intracellular calcium level over a period of 2 h at 22 degrees C or above. This ability was lost at 16 degrees C or below. However, if undiluted semen was slowly cooled (0.125 degrees C/min) even to 5 degrees C and rewarmed to 22 degrees C before dilution, the spermatozoa regained this ability. In contrast, spermatozoa rapidly cooled to 5 degrees C and rewarmed to 22 degrees C before dilution were not able to restore the low intracellular calcium level.     

Affinity purification and subunit structure of soya bean lactate dehydrogenase

The lactate dehydrogenase (LDH) from soya bean has been purified to homogeneity by affinity chromatography. The enzyme was purified by sequential adsor