The beta-(1--

The stimulatory effects of the synthetic beta-(1-->6)-branched beta-(1-->3) glucohexaose and its analogues containing an alpha-(1-->3)-linked bond on the mouse spleen were studied for elucidation of the mechanism of their antitumor activity, and their stimulatory effects were compared with Lentinan. The mouse spleen's weight was increased after the intraperitoneal (i.p.) injection of the oligosaccharides compared with the saline group. In addition, routinely hematoxylin and eosin (HE)-stained spleen sections showed that the injection also changed the spleen's histopathology. RNA samples were isolated from splenocytes of oligosaccharides, Lentinan or saline-injected mice. Reverse transcription-polymerase chain reaction (RT-PCR) and Northern blot showed that the administration of the oligosaccharides or Lentinan enhanced mouse spleen mRNA production of TNF-alpha but not IL-2. The injection also enhanced Concanavalin A (Con A)-induced mouse splenocytes proliferation, but the in vitro administration of the oligosaccharides did not have the proliferation-enhancing effect. Taken together, these results suggest that the synthetic beta-(1-->6)-branched beta-(1-->3) glucohexaose and its analogues containing an alpha-(1-->3)-linked bond have similar stimulatory effects as Lentinan. Additionally, they may exert their antitumor effects through the induction of splenocytes mediated immune responses.

Transfer ionization process p+He -> H-0+He2++e(-) with the ejected electron detected in the plane perpendicular to the incident beam direction

A joint experimental and theoretical study of the transfer ionization process p+He→ H-0+He2++e(-) is presented for 630-keV proton impact energy, where the electron is detected in a plane perpendicular to the proton beam direction. With this choice of kinematics we find the triple-differential cross section to be particularly sensitive to angular correlation in the helium target. There is a good agreement between the experimental data and theoretical calculations.

Revealing the effect of angular correlation in the ground-state He wavefunction: a coincidence study of the transfer ionization process

A joint theoretical-experimental study of the transfer ionization process p + He -> H-0 + He2+ + e(-) is presented. For the first time all particles in the final state have been detected in triple coincidence. This fully differential measurement is in good agreement with a theoretical model where the target is described by a wavefunction containing both radial and angular correlation terms.

Ionization of atomic hydrogen and He+ by slow antiprotons

We study the ionization of H(1s), He+(1s) and He+(2s) by antiprotons in the energy range from 0.1 to 500 keV. We adopt a semiclassical single centre close-coupling approach in which the wavefunction for the electron is expanded in a B-spline basis centred on the nucleus of the atom/ion. Comparison is made with existing theoretical calculations and available experimental data. The results are encouraging.