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Electroabsorption spectra of meso,meso-linked zinc porphyrin arrays doped in a PMMA polymer film have been measured with a field modulation spectroscopy, and the change in electric dipole moment (Δμ) and in molecular polarizability has been evaluated for the transition into each of the exciton splitting components of the Soret band. Δμ following photoexcitation is non-zero in the oligomers, and the magnitude becomes larger with the increasing number of linked molecules, suggesting that photoinduced charge transfer occurs along the linked porphyrin array.

Summary A concentrated live retrovirus is required for in vitro experiments. A cuprammonium-regenerated cellulose hollow fiber, termed BMM, originally developed for biohazardous viral removal, was used to concentrate two different retroviruses, an ecotropic murine leukemia virus (MuLV) and human immunodeficiency virus (HIV). The BMM was useful for concentrating live virus suspension 10- to 30-fold from 500–1000 ml of culture supernatant. The ecotropic MuLV concentrated by BMM was demonstrated to be viable and biologically intact by XC plaque-forming assay and reverse transcriptase assay. The concentrated MuLV reached a much higher titer in the spleen in mice than the original one. The virus concentration assessed by p24 antigen for HIV was clearly higher than that of the original culture supernatant of HIV-infected cell lines. Since BMM hollow fibers trapped viruses by the sieving mechanism but not by adsorption, the viral particles were recovered by washing and the total live virus recovery rate was high, about 50%. Furthermore 60 min sufficed to handle 1000 ml of supernatant in the case of a filtration area of 0.03 m2. These results show that the BMM provides us with a rapid, safe and efficient method for concentrating live retroviruses.

A cytotoxic monoclonal antibody, CALL1, produced against a human schwannoma tumor was found to react with human platelets, common acute lymphocytic cells (cALL), and lymphoblasts from lymphoid blast crisis of chronic myelocytic leukemia (CML). The hybridoma was repeatedly cloned, and the antibody was considered reactive to a single antigen by absorption tests demonstrating that platelets remove cALL activity and cALL cells absorb platelet activity from the antibody. In addition, chromatofocusing showed that the antibody against platelets and cALL had the same isoelectric point. The CALL1 antibody bound to megakaryocytes but inhibited neither myeloid (CFU-C) nor erythroid (BFU- E) colony formation from bone marrow stem cells. Immunoprecipitation and SDS-gel electrophoresis indicated that CALL1 reacts with a polypeptide of 26,000 daltons.

Nonspecific cross-reacting antigen-2 (NCA-2) is a glycoprotein purified from meconium as a closely correlated entity with carcinoembryonic antigen (CEA). As in the case of CEA, only asparagine-linked sugar chains are included in NCA-2. In order to elucidate the structural characteristics of the sugar chains of NCA-2, they were quantitatively released from the polypeptide backbone by hydrazinolysis and reduced with NaB3H4after N-acetylation. The radioactive oligosaccharides were fractionated by paper electrophoresis, serial chromatography on immobilized lectin columns, and Bio-Gel P-4 (under 400 mesh) column chromatography. Structures of the oligosaccharides were estimated from the data of the binding specificities of immobilized lectin columns and the effective size of each oligosaccharide determined by passing through a Bio-Gel P-4 column and were then confirmed by endo-β-galactosidase digestion, sequential digestion with exoglycosidases with different aglycon specificities, and methylation analysis. NCA-2 contains a similar number (27 mol) of sugar chains in one molecule compared with CEA (24-26 mol). However, all sugar chains of NCA-2 were complex-type in contrast to CEA, approximately 8% of the sugar chains of which were high mannose-type (Yamashita, K., Totani, K., Kuroki, M., Matsuoka, Y., Ueda, I., and Kobata, A. (1987) Cancer Res. 47, 3451-3459). About 80% of the oligosaccharides from NCA-2 contain bisecting N-acetylglucosamine residues, and the percent molar ratio of mono-, bi, tri, and tetraantennary oligosaccharides was 2:14:57:27. (± Fucα1→2)Galβ1→4(± Fucα1→3)GlcNAc, (± Fucα1→2)Galβ1→3(± Fucα1→4)GlcNAc, (± Fucα1→2)Galβ1→4(± Fucα1→3)GlcNAcβ1→ 3Galβ1→4GlcNAc, (± Fucα1→2)Galβ1→3(± Fucα1→4)GlcNAcβ1→ 3Galβ1→4GlcNAc, and GalNAcβ1→3Galβ1→3GlcNAcβ1→3Galβ1→4GlcNAc were found as their outer chain moieties. Approximately 60% of the oligosaccharides from NCA-2 contain the Galβ1→4 or 3GlcNAcβ1→3Galβ1→4GlcNAcβ1→group in their outer chains.

The benefits of successful kidney transplants for patients with end stage renal disease associated with insulin-dependent diabetes mellitus are well known, and the potential advantages of earlier transplantation have been emphasized in other reports. Cadaver transplants, which are not always available for these patients, have not provided a high degree of success in many centers. This has discouraged the use of transplants unless well matched related donors are available. Most patients do not have well matched family members who are able to donate. We have attempted to increase the availability of related transplants for diabetic patients by using a new protocol in which related donors who are poorly matched by mixed lymphocyte culture (MLC) testing (stimulation index (SI) ≥7) can often serve as the source of the transplant. This protocol of pretransplant donor-specific transfusions (DSTs) has been applied to 20 diabetic patients. Sixteen transplants have been performed after serial immunological studies following the DSTs detected no specific evidence of recipient sensitization to the respective transfusion donors. Only one of the transplants has been rejected, and this occurred in a patient who intentionally terminated immunosuppressive therapy. Graft survival for the group of 16 patients is 93 and 84 at 1 and 3 years, respectively. The quality of renal function for most of the patients is very good, with a mean serum creatinine of 1.9 and 1.5 mg/dl for those transplants at risk for 12 and 24 months. This new method has given encouraging results for poorly matched related transplants in diabetic patients and makes earlier transplantation possible by providing an alternative to cadaver transplants.

The sugar chains of transferrin samples, purified from sera of patients with hepatocellular carcinoma and of healthy individuals, were released quantitatively as radioactive oligosaccharides by hydrazinolysis followed by N-acetylation and NaB3H4reduction. Comparative study of their structure by serial lectin column chromatography, by Bio-Gel P-4 column chromatography, and by sequential exoglycosidase digestion revealed that prominently altered glycosylation is commonly found in the hepatoma transferrins, although they all contain two complex-type asparagine-linked sugar chains in one molecule like in the case of normal transferrins. The alteration is quite various, including the increase of highly branched sugar chains, of those with the Galβ1 → 4(Fucα1 → 3)GlcN Acβ1 → and the Neu5Acα2 → 3Galβ1 → 4GlcN Acβ1 → groups in their outer chain moieties and of those with a fucosylated trimannosyl core. Many but not all of the hepatoma transferrin samples contained a small amount of a bisected biantennary sugar chain, which was not detected in the normal transferrin samples.

Hydroxyapatite (HA) granules of 100 to 300 µm, 0.9 to 1.2 mm and 3.0 to 5.0 mm were mixed in a ratio of 10:45:45 and packed into massive bone deficiencies in revision operations for total hip arthroplasty. We did not use additional graft or cup support for deficiencies of the lateral and medial wall. The procedure was carried out in 40 hips between 1986 and 1992.The radiographic spaces seen at the interface between HA and bone immediately after surgery disappeared within three months. Some spaces appeared between HA granules near the bone in the lateral part of two joints, and three sockets migrated in patients with severe segmental and cavitary deficiencies. Direct bonding of HA to bone was observed radiologically without morphological changes, except in the three joints with migration. All patients could walk without pain but the three with definite loosening needed crutches.

The carbohydrate binding specificity of Allomyrina dichotoma lectin II was investigated by analyzing the behavior of various complex type oligosaccharides and human milk oligosaccharides on an A. dichotoma lectin II-agarose column. Basically, the lectin interacts with the Gal beta 1—-4GlcNAc group. Substitution of their terminal galactose residues by Neu5Ac alpha 2—-6 will enhance their affinity to the lectin. By contraries, substitution at the C-2 or C-3 position of their terminal galactose with other sugars including sialic acid deprives their affinity to the lectin. With this characteristic, the immobilized lectin column can be used to separate complex type oligosaccharides with the Neu5Ac alpha 2—-6Gal beta 1—-4GlcNAc group from their isomeric oligosaccharides with the Neu5Ac alpha 2—-3Gal beta 1—-4GlcNAc group, where Neu5Ac is N-acetylneuraminic acid.

The presence of recipient lymphocytes in grafts is thought to equate with rejection. Thus, we wished to follow the fate of lymphocytes after transplant of the small bowel. Three complete small-bowel transplants, two with the liver from the same donor also transplanted, were done successfully. Patients were immunosuppressed with FK 506. 5 to 11% of lymphocytes in the recipients' peripheral blood were of donor origin during the early postoperative period when there were no clinical signs of graft-versus-host disease. However, donor cells were no longer detectable after 12 to 54 days. Serial biopsy specimens of the grafted small bowel showed progressive replacement of lymphocytes in the lamina propria by those of the recipient's HLA phenotype. Lymphoid repopulation was complete after 10 to 12 weeks but the epithelial cells of the intestine remained those of the donor. The patients are on enteral alimentation after 5, 6, and 8 months with histopathologically normal or nearly normal intestines. Re-examination of assumptions about the rejection of intestinal grafts and strategies for its prevention are required following these observations.