Inhibition of an early stage of erythropoiesis in cultures of young chick blastodisc cells byRicinus communis agglutinin 120

Summary An early pre-erythroid phase of erythropoiesis in cultures of dispersed cell suspensions prepared from primitive streak and head-fold chick blastodiscs was very sensitive to inhibition byRicinus communis agglutinin 120.This work was supported by grants from the Medical Research Council and National Research Council of Canada. We thank Mrs S. Dorey and N.N. McGrath for technical assistance. S.D.W. is an Associate of the Medical Research Council.     

Red cell metabolism in red and grey kangaroos

Summary Glucose utilization, lactate production and glutathione regeneration were measured in the red blood cells of 2 species of Australian Marsupials, Eastern grey kangaroo (Macropus gigantus) and red kangaroo (Macropus rufus), and were found to be significantly lower in the red blood cells from grey than that of red kangaroos.The author wishes to thank Mrs T. Stephens, M. A. Gruca and A. Mulley for help in blood collection and laboratory work. This work was supported by a grant from the National Health and Medical Research Council of Australia.     

Human adenosine deaminase and chromosome 20

Summary In patients exhibiting in marrow cells deletion of the long arm of chromosome 20, the specific activities of adenosine deaminase in cells of the peripheral blood are normal. This suggests that the gene for adenosine deaminase is not localized to the distal segment of the long arm of this chromosome.This work was supported by Grants from the National Health and Medical Research Council of Australia and the Anti-Cancer Council of Victoria.     

Inhibition and stimulation by 5-bromodeoxyuridine of erythropoiesis by chick blood island cells

Summary Erythropoiesis in liquid cultures of cell populations resolved from chick blastodiscs at the primitive streak and head-fold stages was totally inhibited by 5–8 g/ml of 5-bromodeoxyuridine. However, concentrations of 0.2 /ml of the nucleoside enhanced the number of erythroid cells formed.This work was supported by grants from the Medical Research Council and National Research Council of Canada. We thank MissesK. Beall andN. N. McGrath for technical assistance. S. D. W. is an Associate of the Medical Research Council.     

Atypical mast cell degranulation and focal hydropic degeneration of venular endothelium in diffuse fibrosing alveolitis

Summary Atypical scroll-like and tubular degranulation of mast cells closely associated with focal endothelial hydropic degeneration is reported in human lung from 4 patients with diffuse fibrosing alveolitis in which the predominant abnormality was hyperplasia and desquamation of type 2 pneumocytes.This work was supported by a grant from the National health and Medical Research Council of Australia.     

Familial association in serum IgE levels

Summary The serum IgE levels measured by RIST correlated closely with those obtained by the single radioimmunodiffusion method. Values for husband and wife were closely related as were those between father and daughter but in contrast to previous observations no significant relationship existed between IgE levels for mother and son.Acknowledgments. The Busselton population studies, of which this paper forms part, have been supported by the University of Western Australia the Arnold Yeldham and Mary Raine Foundation, the National Heart Foundation of Australia, Royal Perth Hospital, State Health Laboratories (Western Australia), the National Health and Medical Research Council, Princess Margaret Children's Medical Research Foundation, various private donors, numerous volunteer workers, and the people of Busselton. The authors wish to personally acknowledge support from the Arnold Yeldham and Mary Raine Foundation, the National Health and Medical Research Council and the Asthma Foundation of Western Australia. We are indebted to Drs.K. J. Cullen andR. C. Godfrey for making available valuable material from the Busselton population survey.     

On the mechanism of immunosympathectomy

Summary The effects in vivo and in vitro of the antiserum to mouse nerve growth factor (NGF) are independent of the presence of complement. These results are consistent with the view that the antiserum acts by neutralizing endogenous NGF.Acknowledgments. Financial support from the Whitehall Foundation, New York, The Wellcome Foundation, U.K. (to J.R.C.) and the Science Research Council (Studentship to M.E.) is gratefully acknowledged. We thank Professor J.H. Humphrey, National Institute for Medical, Research, Mill Hill, London, for discussion and determination of plasma C3 levels.     

Location of dopamie stores in rat kidney

Summary In normotensive and genetically hypertensive Wistar rats, chronic renal denervation reduces renal cortical levels of noradrenaline and dopamine by more than 90%. Non-neural stores of renal dopamine are therefore small or absent.This work was supported by the National Heart Foundation of Australia, the National Health and Medical Research Council of Australia and the University of Melbourne. I wish to thank K. Mather and T. Harris for able technical assistance.     

Sarcomere shortening and tension development during ‘isometric’ tetanus of muscle

Summary Laser diffraction and tension measurements from frog muscle during isometric tetanus reveal that the sarcomeres contract more rapidly than tension develops.Supported by the Australian Research Grants Committee and the National Health and Medical Research Council.     

Precocious puberty in rats induced by hypothalamic lesions: A comparison of platinum and stainless steel electrodes

Summary Precocious sexual maturation was induced in immature female rats by 2 types of unilateral hypothalamic lesions. Stainless steel electrodes produced smaller tissue defects but proved more efficient than platinum electrodes.Supported by Swiss National Science Foundation grant No. 3.016.73.Supported by Canadian Medical Research Council grant No. MT 4192.Supported by a contribution from the Roche Research Foundation for Scientific Exchange and Biomedical Collaboration with Switzerland     

A novel effect of cobalt treatment on calcium-dependent responses of the cockroach salivary gland

Summary After incubation in calcium-free solutions containing cobalt, the readmission of calcium caused prolonged but reversible hyperpolarization of acinar cells of cockroach salivary glands and prolonged fluid secretion. It is suggested that cobalt treatment increases the permeability of the acinar cell membrane to calcium.Acknowledgments. We are indebted to the Medical Research Council for support.     

Increased susceptibility ofTrypanosoma lewisi infected,or decomplemented rats toSalmonella typhimurium

Summary Rats infected withTrypanosoma lewisi or decomplemented by injection of cobra venom factor or complement activating factor of trypanosomes were found to be more susceptible to infection withSalmonella typhimurium. Decomplemented rats subsequently infected withT. lewisi developed higher blood parasitemia than did normalT. lewisi infected rats.This project is supported by the National Research Council of Canada grant A 0068 and a grant from the International Development Research Center.     

Adrenal responses to hypoxia and hypercapnia in the young calf

Summary Quantitative analysis of adrenal responses to moderate hypoxia and hypercapnia in the conscious calf shows that the sensitivity of the adrenal cortical response far exceeds that of the adrenal medulla.Acknowledgment. This work has been supported by grants from the Agricultural Research Council, the Medical Research Council and the Wellcome Trust. We are also indebted to Dr D. M. Burley (CIBA) for his continued support.     

Time dependent formation of acetylcholinesterase isozymes

Summary 4 electrophoretically and chromatographically distinguishable forms of 11S acetylcholinesterase were generated during storage of an 11S preparation of the enzyme.Acknowledgments. R. M. Kothari was a Postdoctoral Research Associate of the National Research Council and National Academy of Sciences. Naval Medical Research and Development Command, Research Task No. MF51.524.014.9025. The opinions and assertions contained herein are the private ones of the writers and not to be construed as official or reflecting the views of the Navy Department or the Naval Service at large.     

Association of mastopoiesis with haemopoietic tissues in the neonatal rat

Summary Mast cells in the newborn rat occur in haemopoietic foci of liver and spleen, but disappear from those foci as extramedullary haemopoiesis ceases during the initial postnatal month. At the same time, mast cells increasingly populate bone marrow and connective tissues of heart, lung, stomach and portal tract of liver.J. L. D. acknowledges Scholarships from the National Health and Medical Research Council of Australia while working on this project for the degree of B. Sc. (Med.), the University of New South Wales, and subsequently from the National Heart Foundation of Australia.     

Cannflavin A and B,prenylated flavones fromCannabis sativa L.

Summary Two novel prenylat flavones, termed Cannflavin A and B, were isolated from the cannabinoid free ethanolic extract ofCannabis sativa L. Both compounds inhibited prostaglandin E₂ production by human rheumatoid synovial cells in culture.This communication is dedicated to the memory of the late Professor J. W. Fairbairn and the late Dr. J. T. Pickens. We are grateful to the Medical Research Council for a project grant and to Ms J. Elliot of King's College London for NMR spectra.     

Preparation and properties of hexitol-lysyl conjugates

Summary The facile preparation of hexitol-lysyl derivatives is reported. Some of the properties of these compounds, particularly those relevant to protein structural studies, are described.Supported by grants from Medical Research Council of New Zealand, New Zealand Neurological Foundation and National Heart Foundation of New Zealand.     

Type III (Arthus) allergic reactions and endotoxin toxicity in guinea-pigs

Summary Lipopolysaccharide (endotoxin) fromE. coli cells produced lethal effects in guinea-pigs. Endotoxin caused no visible dermal change in normal animals, but produced skin reactions characterized by specific Arthus-type (Type III immune hypersensitivity) vascular inflammation in immunized animals. It is concluded that Arthus allergic reactions were evoked by endotoxin, however, endotoxin lethal toxicity appears independent of this process.Acknowledgment. Supported by a grant from the National Health and Medical Research Council of Australia.     

Deficits in synapse-to-neuron ratio due to early undernutrition show evidence of catch-up in later life

Summary 30-day-old rats undernourished from birth are known to have large deficits in the synapse-to-neuron ratio in certain brain regions. It has not been possible to demonstrate any statistically significant deficits in this ratio in animals undernourished from birth to 30 days but then provided with an ad libitum amount of food till 6 months of age.Acknowledgments. This work was supported by the Medical Research Council and the National Fund for Research into Crippling Diseases.     

Activation of complement by trypanosomes

Summary Factors exhibiting anti-complementary activity released from trypanosomes after incubation at 20°C were described. The active material was shown to consume the first component of bovine complement. While the anticomplementary factor(s) from T. lewisi could activate bovine, human and guinea pig complement, the factor(s) from T. congolense was observed to activate bovine complement, but not guinea pig and only slightly human complement. The roles of complement activating factor(s) of trypanosomes in the pathology of the disease are discussed.This project is supported by National Research Council of Canada grant A 0068 and a grant from the International Development Research Centre.