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Biomedical subjects

I Ando

Publications and source records attributed to I Ando.

100 records · Page 6Linked to original sources
PubMed1977

[Study of 67Ga distribution in neoplasms and in liver by a cell fractionation method].

Subcellular distribution of 67Ga was quantitatively determined to evaluate the role of lysosome in accumulation of 67Ga in malignant tumor tissue and liver. The following animals and transplanted tumors were used: rats implanted with Yoshida sarcoma and hepatoma AH109A; mice implanted with Ehrlich tumor. 67Ga-citrate were injected to the rats intravenously and to the mice intraperitoneally. Ten minutes to 48 hours after the administration of 67Ga-citrate, the animal were sacrificed, and the tumor tissues and liver were excised. Subcellular fractionation of tumor tissues and livers were carried out according to the method of Hogeboom and Schneider. Radioactivity of each fraction was counted by a well type scintillation counter, and protein of each fraction was measured according to Lowry's method. In Yoshida sarcoma and Ehrlich tumor, most of the radioactivity was localized in the supernatant fraction, and small amount of radioactivity was localized in the mitochodrial fraction (lysosome contains in this fraction). But in the liver, most of the radioactivity was concentrated in the mitochondrial fraction and the radioactivity of this fraction was increased with the passage of time after administration. Twenty-four hours later, about 50% of total radioactivity was accumulated in this fraction. In the case of hepatoma AH109A, radioactivity of mitochondrial fraction was increased with the passage of time after administration, and about 30% of total activity was concentrated in this fraction at 24 hours after administration. From these results it is concluded that lysosome doses not play an important role in the tumor concentration of 67Ga and lysosome plays an important role in the liver concentration of 67Ga. In the case of hepatoma AH109A it is presumed that lysosome plays considerably important role in the tumor concentration of 67Ga, hepatoma AH109A having some nature of liver.

Animals↗
PubMed1977

[Whole-body retention studies of 169Yb-citrate.--Estimation of radiation dose to humans from 169Yb-citrate (author's transl)].

For purpose of the estimation of the radiation dose to humans from 169Yb-citrate, the whole-body retention studies using five rats were carried out. Following intravenous administration of 169Yb-citrate, the whole-body activity was monitored for 40 days by the animal counter. The whole-body retention curve consisted of three components: the first with a 3.6 hours effective half-time, the second with an 154 hours effective half-time and the third with a 29.9 days effective half-time. Therefore it was assumed that 32% of the administered 169Yb-citrate clears from the kidney with a short biologic half-time (3.6hours), 18% remains in the liver and other soft tissues with a relatively long biologic half-time (194 hours) and 50% remains in the bone with a long biologic half-time (850 days). Based on these biological data and the MIRD Committe method, the average dose to the bone and whole-body were 20.8 rads/mCi and 4.5 rads/mCi respectively.

Animals↗
PubMed1977

[Study of distribution of 203Hg-chlormerodrin, 203Hg-nitrate and 99mTc-DMSA in kidney by macroautoradiography (author's transl)].

Serial macroautoradiograms were obtained to determine the distribution of 203Hg-chlormerodrin, 203Hg-nigrate and 99mTc-DMSA in kidney. In the study, normal rats were used and these three radiopharmaceuticals were injected intravenously. Initial images of 203Hg-chlormerodrin showed the accumulation in the outer cortex, but no significant radioactivity in the medullary. On the other hand, delayed images revealed radioactivity shifting in concentration from the outer cortex to the inner cortex. Distribution pattern of 203Hg-nitrate was similar to that of 203Hg-chlormerodrin. In contrast to 203Hg-chlormerodrin and 203Hg-nitrate, 99mTc-DMSA was retained in the outer cortex without temporal changes in the distribution.

Animals↗
PubMed1976

[Affinity of the elements in group VI of the periodic table to tumors and organs].

In order to investigate the tumor affinity radioisotopes, chromium (51Cr), molybdenum (99Mo), tungsten (181W), selenium (75Se) and tellurium (127mTe)--the elements of group VI in the periodic table--were examined, using the rats which were subcutaneously transplanted with Yoshida sarcoma. Seven preprarations, sodium chromate (Na251CrO4), chromium chloride (51CrCl3), normal ammonium molybdate ((NH4)299MoO7), sodium tungstate (Na2181WO4), sodium selenate (Na275SeO4), sodium selenite (Na275SeO3) and tellurous acid (H2127mTeO3) were injected intravenously to each group of tumor bearing rats. These rats were sacrificed at various periods after injection of each preparation: 3 hours, 24 hours and 48 hours in all preparations. The radioactivities of the tumor, blood, muscle, liver, kidney and spleen were measured by a well-type scintillation counter, and retention values (in every tissue including the tumor) were calculated in percent of administered dose per g-tissue weight. All of seven preparations did not have any affinity for malignant tumor. Na251CrO4 and H2127mTeO3 had some affinity for the kidneys, and Na275SeO3 had some affinity for the liver. Na2181WO4 and (NH4)299MoO4 disappeared very rapidly from the blood and soft tissue, and about seventy-five percent of radioactivity was excreted in urine within first 3 hours.

Animals↗
PubMedDate not supplied

Inhibition of HIV-1 infection in vitro by monoclonal antibodies to the complement receptor type 3 (CR3): an accessory role for CR3 during virus entry?

Adhesion molecules are known to contribute to infectivity of HIV-1. Here we tested whether the complement receptor type 3 (CR3, CD11b), an alpha(m)beta2 integrin, plays an accessory role in the infection process of HIV-1, because ICAM-1, a ligand of CR3, is present on the envelope of HIV-1. In addition, the viral transmembrane protein gp41 shares four regions of homology with the complement component C3, a further CR3 ligand. Infection of PBMCs with HIV-IIIB and primary isolates was partially inhibited by anti-CR3 antibodies. A peptide derived from the complement component C3, covering the CR3-binding site of C3 and sharing strong similarity to the immunosuppressive region of gp41, significantly reduced the HIV-1 titer in infection assays. Recombinant soluble gp41 (rsgp41) and the peptide covering the immunosuppressive domain of gp41 inhibited the rosetting of iC3b-coated sheep erythrocytes with U937 via complement receptors (CRs) with an efficiency comparable to monoclonal anti-CR antibodies. In addition, sub-populations of CD4 + and CD8 + T-cells isolated from HIV-infected individuals were found to upregulate CR3 as determined by FACS analysis and on the mRNA level. Since gp41 has been implicated in viral fusion, an interaction of its C3-homology region in gp41 or an interaction of ICAM on the surface of free virus with CRs might contribute to facilitate viral entry.

Anti-HIV Agents↗