King syndrome: a genetically heterogenous phenotype due to congenital myopathies.

We report on a patient with myopathy, kyphoscoliosis, joint contractures, and a facial appearance consistent with King syndrome. Unlike other reported cases, our patient had hyperextensible joints, normal stature, and pectus excavatum. The cardiac ventricles, aorta, and pulmonary artery were dilated. Malignant hyperthermia did not occur under anaesthesia although there was a transient increase in CK levels. Muscle bulk and tone were significantly decreased but collagen and elastin fibres were normal. The variable clinical presentation of King syndrome suggests that the manifestations are caused by different congenital myopathies and in all cases there is probably an increased risk of malignant hyperthermia.     

Effect of leukocyte hydrolases on bacteria

Leukocyte extracts, trypsin, and lysozyme are all capable of releasing the bulk of the LPS from S. typhi, S. typhimurium, and E. coli. Bacteria which have been killed by heat, ultraviolet irradiation, or by a variety of metabolic inhibitors and antibiotics which affect protein, DNA, RNA, and cell wall synthesis no longer yield soluble LPS following treatment with the releasing agents. On the other hand, bacteria which are resistant to certain of the antibiotics yield nearly the full amount of soluble LPS following treatment, suggesting that certain heatlabile endogenous metabolic pathways collaborate with the releasing agents in the release of LPS from the bacteria. It is suggested that some of the beneficial effects of antibiotics on infections with gram-negative bacteria may be the prevention of massive release of endotoxin by leukocyte enzymes in inflammatory sites.     

Effect of leukocyte hydrolases on bacteria

The bactericidal and bacteriolytic effects of lysolecithin (LL) and egg-white lysozyme (LYZ) on Staph. aureus and group A streptococci and the solubilization of phospholipids from the bacterial membranes by these agents was studied. Low concentrations of lysolecithin (1--10 microgrames/ml) are highly bactericidal for Steph. aureus and group A streptococci, but induce neither bacteriolysis nor solubilization of a substantial amount of membrane phospholipids. On the other hand, while LL at greater than 50 micrograms/ml causes substantial lipid release, a combination of LL and LYZ is absolutely needed to solubilize lipids from streptococci. This combination is, however, not bacteriolytic for this microrganism. The solubilization of lipids from staphylococci by LL is much faster than that induced in streptococci by LL + LYZ. The solubilization of the bulk of membrane lipids from staphylococci can also be achieved by Triton X-100 and by sodium lauryl sulfate and from group A streptococci by Triton X-100 plus LYZ. A variety of other detergents (e.g., Cetavlon, sodium taurocholate, cetyl pyrdinium chloride) have no lipid-releasing properties even in the presence of LYZ. The release of lipids by LYZ (in the presence of LL) from group A streptococci is related to its enzymatic activity, on a still unknown substrate, but not to its cationic nature as this muramidase cannot be replaced by a variety of cation substances (histone, polylysin, leukocyte cationic proteins, polymyxin B, and spermidine). The release of lipids from staphylococci by LL is not inhibited by a variety of anionic and cationic polyelectrocytes (heparin, liquoid, chondroitin sulfate, DNA histone, and polylysine) which markedly inhibit the release of lipids from group A streptococci by LL and LYZ. Streptococci that had been cultivated in the presence of subinhibitory concentrations of penicillin G lose their membrane phospholipids to a larger extent and by much smaller concentrations of LL and LYZ, as compared to controls, suggesting that the interference with the synthesis of the peptidoglycan increases the accessibility of the cell membrane to the lipid-releasing agents. The mechanism by which LL collaborates with LYZ in lipid release is still not known. The possible role of bacterial lipids and lyso compounds in the control of bacterial survival in inflammatory sites is briefly discussed.     

Evidence on major gene control of cortical index in pedigree data from Middle Dalmatia,Croatia

It was recently reported that the inheritance of the metacarpal cortical index (CI) in the Chuvashian population can be described in terms of a major gene (MG) model. By applying transmission probability tests, the hypothesis was accepted that not only baseline level of CI but also its sex‐specific dependence on age were under control of the same putative large‐effect gene. Using a pedigree sample from the population of the islands of Middle Dalmatia, Croatia (847 observed individuals in 278 pedigrees), data are presented to support the above findings. The following hypotheses were accepted: (i) inheritance of baseline CI in the Croatian population can be attributed to the effect of a MG responsible for about 42% of the variation; (ii) the same MG takes part in the control of the dependence of CI on age, particularly the age at onset of involutive bone changes (inflection point), and of the rate of decrease in CI with age (slope coefficient). Issues related to the assortative mating effect on CI and the determination of the most parsimonious model are discussed. Am. J. Hum. Biol. 13:398–408, 2001. © 2001 Wiley‐Liss, Inc.     

The preparation and properties of porcine neurophysin and the influence of calcium on the hormone-neurophysin complex

1. The preparation of a hormone-binding protein fraction (neurophysin) from porcine neurohypophyses is described.2. It was shown by gel-filtration that the protein (which sedimented as a single component on analytical ultracentrifugation) forms complexes with oxytocin and lysine vasopressin. The maximum capacity of porcine neurophysin to bind oxytocin and lysine vasopressin was estimated from the results of dialysis experiments as 232 u. oxytocin and 48 u. lysine vasopressin/mg protein.3. Binding of oxytocin and lysine vasopressin by neurophysin was completely inhibited in the presence of calcium in concentrations greater than 10(-6)M but is unaffected at less than 10(-7)M-Ca. The concentration of calcium required to inhibit binding did not appear to be dependent on hormone or protein concentrations.4. No evidence was obtained that calcium was bound by neurophysin or by the peptide hormones either alone or in combination.5. These results are discussed in the light of the hypothesis that release of the hormone from the neurohypophysis is mediated by calcium.