To determine immunosuppression by leukocytapheresis, we studied the immune profiles of filter-passed lymphocytes (FPLs) in patients with ulcerative colitis. These patients were treated with a leukocytapheresis (LCAP) filter of granulocyte apheresis (GCAP) column. Cytokine profiles or FPLs and peripheral blood mononuclear cells (PBMCs) were examined using interleukin (IL)-4 and interferon-gamma (IFN-gamma) immunoassay with lectin stimulation. The IL-4 production of LCAP FPLs was significantly higher than in prefilter PBMCs and GCAP column-passed lymphocytes (median: 540 pg/ml x 10(6) cells versus 4.7 and 2.9, respectively, p = 0.001). IL-4 production in PBMCs was increased after LCAP. IFN-gamma production was not increased in the FPLs. The IL-4 immune deviation was not shown in the patients treated with GCAP. LCAP FPLs showed increased CD4+DR- cells and decreases CD4+DR+ cells in comparison to PBMCs. LCAP FPLs could produce IL-4 and may lead to bystander suppression.

"Cap polyposis" is a rarely-encountered condition in which distinctive inflammatory polyps are located from the rectum to the distal descending colon. Microscopically, the polyps consist of elongated, tortuous, and distended crypts covered by a "cap" of inflammatory granulation tissue. Although the pathogenesis is unknown, mucosal prolapse has been postulated to be an important etiological factor, given certain clinical and histological similarities. We describe two cases of cap polyposis with protein-losing enteropathy. One was treated successfully by avoidance of straining at defecation. Another resolved after double-barreled transverse colostomy. Both successful treatments support a causal link of polyposis to prolapse.

The quality of CT images depends on the characteristics of the X-ray detector. In place of conventional xenon ionization detectors, we have designed a highly efficient solid state detector with low detector noise by using a Gd2O2S ceramic scintillator.

A modified procedure for bentonite purification and a new method for the quantitative characterization of bentonite using smectite content are reported. Bentonite found in a drill core of Tsunagi Mine, Niigata, Japan was evaluated by the new method to demonstrate the substantial increase in smectite content from 40% in the original bentonite to 75% after purification using a new procedure. Powder samples were prepared by putting blocks of bentonite into acetone to remove water without mechanical crushing. The powdered, acetone-dried bentonite was purified by a dispersion-sedimentation method in water after cation exchange of the interlayer Ca2+ ion with Na+ ion by the reaction of raw bentonite with aqueous NaCl. The purification was evaluated using X-ray diffraction and thermogravimetric analyses (TG). The raw bentonite contained feldspar, quartz, and cristobalite, and feldspar and quartz were removed by the new purification procedure. The purification was evaluated quantitatively by comparing the TG data before and after the purification. The purified bentonite swelled in water to give a stable aqueous suspension and 3 g of purified bentonite dispersed in 60 mL of water was stable for several days. The replacement of interlayer sodium with dibehenyldimethylammonium gave an organophilic clay, which swelled in toluene. The bentonite has potential practical uses as a purified bentonite and an organophilic bentonite.

Dioleyldimethylammonium ion was used to construct two-dimensional hybrid structures with clay and the hybrid was shown to possess higher flexibility than that of the hybrid of dioctadecyldimethylammonium and the clay. The important difference between the two surfactant systems was studied by quasi-elastic neutron scattering, confirming the useful characteristics of the presently designed dioleyldimethylammonium-clay over the well-known dioctadecyldimethylammoniumclay for various materials applications.