Role of Th2 cytokines, Rantes and eotaxin in AIDS-associated eosinophilic folliculitis

The pathogenesis of AIDS-associated eosinophilic folliculitis is still unknown. The expression of chemokines and Th2-type cytokines is increased in other conditions associated with tissue eosinophilia and in allergic reactions. We evaluated the mRNA expression by reverse transcriptase polymerase chain reaction of two Th2 cytokines (interleukin-4 and interleukin-5) and of two chemokines (RANTES and eotaxin) in the skin of 6 patients with AIDS-associated eosinophilic folliculitis; the tissue localization of eotaxin was shown by immunohistochemistry. We demonstrated the increased expression of interleukin-4, interleukin-5, RANTES and eotaxin in lesional skin of the patients compared to normal skin of HIV+ individuals. We concluded that a Th2 pattern is present in AIDS-associated eosinophilic folliculitis. The cytokine milieu in this disease may favour a Th2 immune response to an unknown antigen, whereby RANTES and eotaxin act in synergy with interleukin-4 and interleukin-5 to mediate tissue inflammation

Confirmation of a soft photon signal in excess of QED expectations in pi(-)p interactions at 280 GeV/c

Photons produced in pi(-) p interactions at 280 GeV/c were detected by reconstructing the e(+)e(-) pairs produced via the materialisation of the photons in a 1 mm thick lead sheet placed in front of the MWPC’s of the OMEGA spectrometer at CERN. A soft photon signal 7.8 +/- 1.5 times the Q.E.D. inner bremsstrahlung prediction was observed confirming the results of a previous experiment. (C) 1997 Elsevier Science B.V

OBSERVATION OF A NARROW SCALAR MESON AT 1450 MEV IN THE REACTION PP-]PF(PI+PI-PI+PI-)P(S) AT 450 GEV/C USING THE CERN OMEGA-SPECTROMETER

The reaction pp –> pf (pi+ pi- pi+ pi-)ps has been studied at 450 GeV/c in an experiment designed to search for gluonic states. In addition to the well known f1(1285), the pi+ pi- pi+ pi- mass spectrum shows evidence for two states previously only observed by the WA76 experiment, the X(1450) and X(1900). An analysis of the X(1450) shows that it is a relatively narrow state (GAMMA = 56 +/- 12 MeV) with I(J(PC)) = 0(0++) which decays to rho0pi+ pi-. The X(1900) could either be a single broad state (GAMMA = 370 +/- 70 MeV) with I(J(PC)) = 0(2++) or possibly two separate states

FIRST RESULTS FROM EXPERIMENT-WA91 AT THE CERN OMEGA-SPECTROMETER

Experiment WA91 searches for non-q (q) over bar mesons produced in the central region in the reaction pp –> p(f)(X(0))p(s) at 450 GeV/c using the CERN Omega Spectrometer. WA91 is a continuation of the WA76 experiment which has studied this reaction using beams of 85 and 300 GeV/c. Preliminary results from experiment WA91 are presented. In particular the X(1450) and X(1900) observed for the first time in the pi(+)pi(-)pi(+)pi(-) channel of the WA76 experiment at 300 GeV/c are confirmed by the WA91 data

Pion and proton production in proton-tungsten and sulphur-tungsten interactions at 200 GeV/c per nucleon

Production of charged particles identified by a multi cell threshold Cerenkov counter in proton-tungsten and central sulphur-tungsten collisions at 200 GeV/c per nucleon is discussed. The pi(+/-), p and (p) over bar production ratios and transverse mass spectra at central rapidity and p(T) > 0.6 GeV/c are presented and compared with results from other experiments at the same beam energy. (C) 1997 Elsevier Science B.V

A FURTHER STUDY OF THE CENTRALLY PRODUCED PI(+)PI(-) AND PI(+)PI(-)PI(+)PI(-) CHANNELS IN PP INTERACTIONS AT 300 AND 450 GEV/C

An analysis of the centrally produced pi(+)pi(-) and pi(+)pi(-)pi(+)pi(-) mass spectra from the WA76 and WA91 experiments is presented, which shows that in the pi(+)pi(-)pi(+)pi(-) channel there are two new states, the f(0)(1450) and f(2)(1900). There is another new state in the pi(+)pi(-) channel with M = 1497 +/- 30 MeV and Gamma = 199 +/- 30 MeV, which is compatible with the f(0)(1520) observed by the Crystal Barrel experiment. Another interpretation is discussed, where the 1450 and 1497 GeV structures are explained as being due to an interference effect between the f(0)(1365) and f(0)(1520)

Charged particle production in S-S collisions at 200 GeV/c per nucleon

Charged particle production in central S-S collisions at 200 GeV/c per nucleon has been studied by the WA94 experiment at the CERN-SPS. Particle identification has been provided by the Omega RICH, while a silicon telescope in the Omega spectrometer and an array of MultiWire Proportional Chambers have been used to trace particles through the RICH detector. Production ratios and transverse mass spectra for pi(+/-), K+/- and p((p) over bar) at central rapidity and p(T) > 1.3 GeV/c are presented. (C) 1997 Elsevier Science B.V

Enhancement of strange and multi-strange baryons and anti-baryons in SW interactions at 200 GeV/c

Strange and multistrange baryon production is expected to be enhanced in heavy ion interactions if a phase transition from hadronic matter to a Quark-Gluon Plasma takes place. The production yields of Lambda s, <(Lambda)over bar>s, Xi(-)s, and <(Xi)over bar>(+)s relative to the production of negative particles are presented for sulphur-tungsten interactions at 200 GeV/c per nucleon. These production yields are compared to those produced in proton-tungsten interactions and the enhancements of strange and multistrange baryons and antibaryons are presented. (C) 1999 Elsevier Science B.V. All rights reserved

Hyperon production in proton-tungsten interactions at 200 GeV/c

The relative production yields and transverse mass spectra for Lambda,<(Lambda)over bar>,E(-) and (E) over bar(+) hyperons in proton-tungsten interactions are presented and compared with the WA85 results from central sulphur-tungsten interactions. A study of the negative particle yield has also bean undertaken and the ratio of Lambda hyperons to negative particles has been calculated