MICROENVIRONMENTALLY DEPENDENT EFFECTS ON MURINE HEMATOPOIESIS BY A PROLONGED INTERLEUKIN-1 TREATMENT

We administered recombinant human IL-1beta (400 ng/d, s.c.) for 10 d to normal C57B1 mice and determined daily granuloid and erythroid parameters in marrow, spleen and blood. In the marrow CFU-GM numbers were not affected but later granuloid cell stages were moderately enhanced (170%). In the spleen, however, CFU-GM numbers were sharply increased (1600%), whereas the granuloid precursors only doubled. Blood granulocytes increased transiently to 275% on day 5. In the marrow all erythroid parameters were severely reduced. This reduction was partially compensated by the spleen where initially only BFU-E and with some delay also more mature erythroid cells accumulated. At the end of the treatment mice were slightly anaemic. When mice were treated with IL-1 and erythropoietin (10 U/d) simultaneously, the inhibitory effects on erythropoiesis were less severe. In agreement with in vivo results, IL-1 inhibited in vitro colony growth of CFU-E from normal bone marrow and spleen but spleen CFU-E from 5 d IL-1 treated mice were insensitive. We conclude that IL-1 can induce stimulation or inhibition of haemopoietic progenitor cells depending on their microenvironment

A STUDY OF THE REACTION p p ---> p p X AT ISR ENERGIES

The authors have performed an experiment to investigate the reaction p +p to p/sub 1/+p/sub 2/+X at the CERN Intersecting Storage Rings (ISR) . The dependence of the cross-section on the mass and rapidity of the system X, and on the momentum transfer squared t/sub 1/, t/sub 2/ to the outgoing protons is studied. They observe signals for the production of rho , omega , f, and A/sub 2/ mesons in the missing-mass spectra, and conclusions are made about the contribution of double- Pomeron exchange. (9 refs)

SEARCH FOR THE NEW LONGLIVED PARTICLES WITH MASSES IN THE RANGE 1.4-GeV TO 3.0-GeV AT THE CERN ISR

A search has been made at the CERN ISR for long-lived non-annihilating particles of two types: those which exhibit strong interactions and those which do not (heavy leptons). Invariant cross section upper limits of 6 nb GeV/sup -2/ and 1.8 nb GeV/sup -2/ were measured for these two classes of particles, respectively, for particle masses close to the anti-deuteron mass. Upper limits are also placed on the production of new particles with masses in the range 1.4 to 3.0 GeV, and invariant cross sections are quoted for pi , p, d production. The experiment was performed at square root s=53 GeV with x (=2p/sub L// square root s) in the range 0.07 to 0.15 and p/sub T/ between 0.08 and 0.16 GeV/c. Antideuterons were identified by annihilation in a 1.4 m /sup 3/ scintillation calorimeter. (19 refs)

Measurement of coherent elastic and inelastic deuteron-proton scattering at s=2800 GeV2

Data on coherent elastic and inelastic deuteron-proton scattering are presented. The measurements were made at the CERN ISR with a single arm spectrometer, at s=2800 GeV/sup 2/ and momentum transfer squared (-t) in the range 0.15 to 0.42 GeV/sup 2/. The data are compared with elastic and inelastic proton-proton scattering data taken with the same apparatus at the same s and t values. The t dependence of the elastic dp to dp differential cross section is compared with simple predictions based on Glauber theory. The differential cross sections for pp to pX and dp to dX are also compared for M/sub X//sup 2/ to 280 GeV/sup 2/, where M/sub X/ denotes the mass of system X recoiling against the measured proton and deuteron. (25 refs)