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Biomedical subjects

H Aoki

Publications and source records attributed to H Aoki.

At least 649 records · Page 36Linked to original sources
PubMed1979

Regulatory functions of hapten-reactive helper and suppressor T lymphocytes. III. Amplification of a generation of tumor-specific killer T-lymphocyte activities by suppressor T-cell-depleted hapten-reactive T lymphocytes.

2,4.6-trinitrophenyl (TNP)-reactive T-cell activities were raised in mice by immunization with TNP-isologous mouse gamma globulin. After establishing that TNP-reactive T lymphocytes can serve as amplifier cells for induction of killer T lymphocytes in allogeneic system, we explored the possibility of this hapten-reactive T-cell system to amplify tumor-specific killer T-lymphocyte activity in the syngeneic system. We utlized relatively weak immunogenic syngeneic plasmacytoma X5563 in C3H/He mice. Analysis of the TNP-reactive T-cell activities revealed that such T lymphocytes express the biological functions of both major subtypes of regulatory T cells, namely suppressors and helpers, and that TNP-reactive suppressor and helper T lymphocytes, respectively, differ in their relative susceptibility to specific inactivation by TNP conjugates of the nonimmunogenic D-amino acid copolymer, D-glutamic acid, and D-lysine (D-GL). By taking advantage of the relative susceptibility-difference to TNP-D-GL, selective inactivation of TNP-reactive suppressor T cells was induced by appropriate treatment with TNP-D-GL, and the generation of TNP-reactive helper T-cell activity was amplified. The supplement of augmented TNP-reactive helper T-cell activity to the system at the immunization with syngeneic X5563 with TNP-haptenation, resulted in a striking augmentation of induction of tumor-specific killer T-lymphocyte activity, and a considerable number of hosts survived after the challenge with lethal dose of viable tumor cells. Thus, appropriate manipulations designed to induce potent hapten-reactive helper T-lymphocytes provided the potential for a very effective mode of immunoprophylaxis against tumor.

Animals↗
PubMed1979

Protection of mice against virulent virus infection by a temperature-sensitive mutant derived from an HVJ (Sendai virus) carrier culture.

Experimental infection with HVJ (haemagglutinating virus of Japan-the Sendai strain of parainfluenza 1 virus) in mice was studied. Aerosol infection of newborn mice with the wild-type virus (HVJ-W) retarded the development of body weight and killed the animals within a few weeks. Large amounts of virus were isolated from both the lungs and the nasal turbinates of infected mice. In contrast, newborn mice exposed by inhalation to a temperature-sensitive (ts) mutant (HVJ-pB) derived from an HVJ carrier culture showed no clinical signs and grew equally well as mock-infected animals. No infectious virus could be recovered from the lungs although the ts mutant grew to moderate titre in the nasal turbinates. The prior inoculation of newborn mice with the ts mutant virus induced a state of significant resistance to subsequent challenge with the virulent wild-type virus. No replication of challenge virus in both lungs and nasal turbinates could be detected and the animals were protected a lethal infection. It is suggested that an avirulent temperature-sensitive mutant which has lost the capacity to replicate in the lower respiratory tract but is still capable of multiplying in the nasal turbinates may be a promising candidate for use in live vaccines especially against the infectious disease of the lower respiratory tract.

Animals↗
PubMed1979

Biocompatibility of apatite ceramics in mandibles.

Apatite ceramics composed of synthetic hydroxyapatite, Ca10(PO4)6(OH)2 were implanted in mandibles of adults dogs. The histological observations indicated that the apatite ceramic was closely contacted with newly formed bone tissue without any rejection phenomenon up to 2 weeks. An electron micrograph of non-decalcified ultra-thin section at 8 weeks showed that the apatite ceramic was directly bonded to newly formed bone and the mineralized bone tissue was grown into the micro pores of the ceramics independent on the pore size. It seemed that the outer surface of the apatite was exchanged by bone tissue. From these results it was considered that the apatite ceramic was a successful implant material in dental and surgical fields.

Animals↗
PubMed1978

[Changes in serum thyrotropin, thyroxine and triiodothyronine after complete thyroidectomy (author's transl)].

Changes in serum TSH, T4 and T3 concentrations after complete thyroidectomy were observed for 4 weeks in 9 euthyroid patients with thyroid carcinoma. Completeness of the thyroidectomy was confirmed by a 131 I scintigram performed one or two months after the operation. Serum TSH levels rose progressively during the 4 weeks of observation, and a significant increase was noticed as early as 3 days after the thyroidectomy. Serum T4 and T3 concentrations decreased significantly 3 days and 18 hrs, respectively, after the thyroidectomy. A sharp decrease in serum T3 concentrations within 18 hrs without a significant change in serum T4 levels and possibly without a significant change in the amount of T3 derived from T4 suggests that the amount of T3 secreted from the thyroid is large enough to affect serum T3 concentrations. The rate of decrease of serum T4 (t 1/2: 16 days) or serum T3 (t 1/2: 23 days) after the 3rd day of the thyroidectomy was much slower than the rate of disappearance of labeled T4 or T3 reported previously. The slow decrease rate of serum T3 is probably due to the conversion of T4 to T3 in peripheral tissues, and that of serum T4 may be due to either the decrease in T4 disposal rate in hypothyroidism or due to the release of T4 from peripheral tissues to serum.

Adult↗
PubMed1978

Prostaglandin-induced eosinopenia in splenectomized rats.

PGE1, PGE2, and PGF2alpha over a dose range of 1 to 50 microgram/kg decreased the number of circulating eosinophils in splenectomized rats. Pretreatment with a beta-blocking agent, propranolol, did not alter this effect, but adrenalectomy eliminated it. Anterior hypothalamic destruction also abolished eosinopenia induced by PGE1 and PGF2alpha but not that induced by PGE2.

Adrenalectomy↗
PubMed1978

Hydroxyapatite-reactive salivary protein revealed by iso-electrofocusing electrophoresis.

Salivary protein involvement in the formation of acquired enamel pellicle, so far, has been discussed in terms of hydroxyapatite (HA)-reactive salivary proteins only from the parotid gland. This study was undertaken to seek this type of protein in the human whole (mixed) saliva and to investigate its normal and pathological variations. Several kinds of hydroxyapatite, either biogenous or synthesized by solid phase reaction, were used as a powder (250 mesh). HA was incubated with concentrated whole saliva at 25 degrees for 30 min. After centrifugation and filtration salivary proteins were analysed on a Multiphor isoelectrofocusing gel electrophoresis. The control salivary proteins were separated into three major groups; acidic (A1-A8), neutral neutral (N1-N4), and basic (B1-B3) isoelectric point (pI). In the HA incubated sample, one of the major neutral bands (NI) preferentially disappeared at about pI 7.5. This NI band was missing or scarce in the parotid saliva and had an amino acid composition rich in glycine, lysine, serine, glutamic acid, aspartic acid, and histidine. This protein was considered to be one of the major HA-reactive proteins in human whole saliva.

Adsorption↗