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Biomedical subjects

I Ando

Publications and source records attributed to I Ando.

At least 37 records · Page 2Linked to original sources
PubMed1997

Functional activation of cerebral blood flow abolished by scopolamine is reversed by cognitive enhancers associated with cholinesterase inhibition: a positron emission tomography study in unanesthetized monkeys.

The effects of somatosensory stimulation on the regional cerebral blood flow (rCBF) response were studied in unanesthetized monkeys before and after treatment with scopolamine and three cognitive enhancers (physostigmine, E2020 and tacrine) that inhibit cholinesterase, using 15O-labeled water and high-resolution positron emission tomography. Under control conditions, somatosensory stimulation induced a significant increase in the rCBF response in the contralateral somatosensory cortex of monkey brain. Intravenous administration of scopolamine (50 microg/kg) resulted in abolishment of the rCBF response to stimulation. The rCBF response abolished by pretreatment with scopolamine was recovered by administration of physostigmine (1 or 10 microg/kg), E2020 (10 or 100 microg/kg) or tacrine (100 or 1000 microg/kg), in a dose-dependent manner. The effect of E2020 (100 microg/kg) on the rCBF response lasted for >4 hr, whereas the effects of physostigmine and tacrine were of shorter duration. These findings suggest that these compounds reversed the scopolamine-abolished rCBF response to somatosensory stimulation via enhancement of cholinergic neurotransmission, which was mainly induced by cholinesterase inhibition.

Animals↗
PubMed1996

Assignment of genes coding for leukocyte surface molecules to river buffalo chromosomes.

A panel of 35 somatic cell hybrids between river buffalo (Bubalus bubalis L.) and Chinese hamster was used in combination with 40 monoclonal antibodies to find synteny among leukocyte antigens and between already established synteny groups and leukocyte antigens. Six synteny groups were identified and three sets of markers were related to already existing synteny groups. Antibody IL-A165 detected CD71, which is syntenic with synteny groups U10 and U25, confirming that U10 and U25 are both are on a biarmed river buffalo chromosome. This would imply that U25 could be assigned to the short arm of the river buffalo chromosome 1 (BBU 1p), as U10 has previously been assigned to this chromosome. Antibodies Buf 32, Buf 24 and BAGB27 detected an antigen syntenic with U1 and U7. This finding suggests that U1, which is assigned to cattle chromosome 16, which corresponds to river buffalo chromosome 5q, is syntenic with U7, and that U7 is located on the short arm of buffalo chromosome 5. Furthermore, the gene coding for CD14 is assigned to U16, which is on cattle chromosome 11 and expected to be on river buffalo chromosome 12.

Animals↗
PubMed1996

Alteration of human melanoma gangliosides by IFN-gamma, IL-2, and IL-4.

In lesions of malignant melanoma, melanoma cells are exposed to various cytokines produced by inflammatory reactions. As a result, transformation of melanoma cells is expected to occur. We studied alterations in human melanoma cell line ganglioside composition after exposing melanoma cell lines to interferon (IFN)-gamma, interleukin (IL)-2, and IL-4 by biochemical methods. IFN-gamma increases the ratio of a-series gangliosides and the ratio of GM3/GD3. This suggests an alteration of immunoreactivity, a decrease in ganglioside sialyltransferase II activity, and an decrease in the malignant character of these cells. The alteration of the ganglioside profile varied among cytokines and cell lines. The progression of malignant melanoma may be influenced by reciprocal interactions between the melanoma cells and the host immune system.

Gangliosides↗
PubMed1995

Effects of glutamate dehydrogenase, choline oxidase, and glucose-6-phosphatase on 67Ga accumulation in lysosome.

AIM: To clarify the effects of the activities of hepatic enzymes in liver, hepatoma, and malignant tumor on 67Ga accumulation in lysosome. METHODS: 67Ga-citrate solution was prepared from carrier-free 67Ga-citrate solution 0.08 mol.L-1 and sodium citrate solution 0.08 mol.L-1, and was injected iv 0.4 ml to the rats. Subcellular fractions of the liver were measured for radioactivity of 67Ga by a well-type scintillation counter (Aloka JDC-701). Glutamate dehydrogenase, choline oxidase, and G-6-P activities were calculated as described by Shimizu H, Ikuta S, and Baginski E, respectivily. RESULTS: 67Ga radioactivity in normal liver lysosome (55%) was significantly higher than those in hepatoma AH 109A (32%) and Yoshida sarcoma (18%). Glutamate dehydrogenase activities were 1830 +/- s 320 U.L-1 in normal liver while 23 +/- s 6 U.L-1 in hepatoma AH 109A, and 7 +/- s 2 U.L-1 in Yoshida sarcoma. Choline oxidase activities were 46 +/- s 10 U.L-1 for normal, 25.0 +/- s 0.4 U.L-1 for hepatoma AH 109A, and 2.0 +/- s 0.4 U.L-1 for Yoshida sarcoma. G-6-P activities were 2550 +/- s 180 U.L-1 in normal, 84 +/- s 14 U.L-1 in hepatoma AH 109A, and 78 +/- s 13 U.L-1 in Yoshida sarcoma. CONCLUSION: Lysosome of normal rat liver in which hepatic enzymes work actively played a major role in the tissue concentration of 67Ga, but the role diminishes with the neoplastic transformation into hepatoma. The lysosome of Yoshida sarcoma does not play any role in 67Ga accumulation because it does not possess any features of liver.

Alcohol Oxidoreductases↗
PubMed1994

Biodistributions of radioactive bipositive metal ions in tumor-bearing animals.

Distributions of the nuclides 65ZnCl2, 85SrCl2, 58CoCl2 and 103PdCl2 in tumor-bearing animals were determined, and, in addition, the distributions of these nuclides in tumor tissues were observed. Their subcellular distribution in tumor and liver was also examined. Generally speaking, retention values of these bipositive metal ions in tumor were smaller than those of tri-, quadri- and pentavalent metal ions. In the case of 85SrCl2, a large amount of this nuclide was taken up by the bone and remained there for a long time. In the case of 103PdCl2, 103Pd was avidly taken up by the kidney and liver. Very little of the 103Pd taken up into the kidney and liver was excreted. 65Zn and 103Pd were concentrated in the viable tumor tissue and were not seen in necrotic tumor tissue. In the case of 58Co, lysosome played an important role in liver accumulation and played a minor role in tumor accumulation. The distribution of 58Co in tumor and liver was fairly similar to that of 67Ga, 111In, 169Yb, 46Sc, 51Cr, 95Zr, 181Hf, 95Nb and 182Ta which were reported previously. Lysosome did not play an important role in the accumulation of 65Zn, 85Sr and 103Pd into tumor and liver.

Animals↗
PubMed1994

Effect of phytohaemagglutinin on CD45 in T cells.

In this study the effect of PHA activation on the phosphatase activity of CD45 has been investigated in human leukemic T-cell lines. It has been found that in vivo activation of the cells with PHA resulted in 2-4-fold increase in enzyme activity. Addition of PHA to the postnuclear supernatant of cell lysates also resulted in elevation of phosphatase activity. Elevation of enzyme activity resulted from an increase in the amount of antigen in the immunoprecipitates. Elevation of the quantity was not the result of a de novo protein synthesis since the presence of cycloheximide, a protein synthesis inhibitor, did not modulate the effect of PHA. The effect of PHA was specific since ConA, that also bound to the CD45 molecules, or crosslinking of the antigen by antibody did not affect CD45. Since direct binding of PHA to CD45 molecules was shown in immunoblotting analysis, we suggest that the effect of PHA is a consequence of a PHA-induced conformational change of CD45 that results in up-regulation of the analyzed CD45 epitopes.

Humans↗
PubMed1994

Tumour affinity of 203Pb-chloride: comparison with 67Ga-citrate and 201Tl-chloride.

The radionuclide 203Pb decays completely by electron capture to stable 203Tl with a half-life of 52 h. The primary radiation from the decay is gamma-ray radiation 280 keV (80%). 203Pb is produced easily from the natural metal thallium by the method described below. 203Pb-chloride is a promising imaging agent for tumour scanning because of the large retention value for tumour tissue and the small value for normal organs, but the large value for the kidney and bone is a shortcoming when considering it as an imaging agent. The retention value of 203Pb in tumour tissue is larger than that of 201Tl and smaller than that of 67Ga. The tumour/inflammatory lesion retention ratio for 203Pb is very large in comparison with those for 67Ga and 201Tl. 203Pb accumulates to a large extent in viable tumour tissue, and less in necrotic tumour tissue and in inflammatory lesion. Therefore, 203Pb-chloride is far better for visualization of viable tumour tissue than 67Ga and 201Tl if the large retention values for the kidney and bone were reduced.

Animals↗
PubMed1994

Perforating lichen nitidus.

A 32-year-old man with no particular family history nor past history visited our clinic in September 1992, with papules that he claimed had developed approximately 3 years earlier. No subjective symptoms accompanied then. On examination, numerous, discrete, pinhead-sized or half-ricecorn-sized, flesh-colored papules were observed on the dorsolateral side of his left hand and fingers. No central dimple or scaling were noticed clinically (Fig. 1). Laboratory tests revealed no abnormal findings. The histopathology of the biopsied specimen showed a circumscribed nest of infiltrating cells closely attached to the epidermis (Fig. 2). These infiltrating cells consisted of mononuclear lymphoid cells and histiocytes. The overlying epidermis was stretched and atrophic. A transepithelial perforation channel existed in direct contact with the surface. Amorphous debris containing cell nuclei lay within the channel (Fig. 2). Lymphoid cells were also observed above the keratin layer overlying the channel. At the lateral margin of the infiltrate, rete ridges extended downward in the manner of a claw clutching a ball. In a periodic-acid-Schiff (PAS)-stained section, a basement defect was observed around the channel.

Adult↗
PubMed1994

DF3 (CA15-3) antibody as a marker of cutaneous adnexal tumors.

DF3(CA15-3) monoclonal antibody detects the 20 amino acid sequence of epithelial mucin. In normal cutaneous tissue DF3 antibody exhibits strong and constant positive reactivity with sebaceous and secretory segments of eccrine and apocrine sweat glands. All epidermal tumors are DF3 negative but poorly differentiated squamous cell carcinoma. Various adnexal tumors such as eccrine hidrocystoma, tubular apocrine adenoma, syringocystadenoma papilliferum, eccrine poroma, eccrine spiradenoma, clear cell hidradenoma, mixed cell tumor, eccrine porocarcinoma, extramammary Paget's disease and adenoid cystic carcinoma are DF3 positive, which indicates epithelial mucin production by these tumors.

Adenoma↗
PubMed1993

Difference in clinical features and HLA antigens between familial and non-familial vitiligo of non-segmental type.

Of 131 patients with non-segmental vitiligo studied, 29 (22%) had a family history of this disorder. The clinical features and HLA antigens were assessed, and a comparison made between patients with familial and those with non-familial, non-segmental vitiligo. Familial patients developed skin lesions significantly earlier than non-familial patients. There was a significant association between HLA-B46 and familial non-segmental vitiligo, whereas HLA-A31 and CW4 were found in non-familial patients. The differences in clinical features and HLA phenotypes suggest heterogeneity in the pathogenic process between familial and non-familial vitiligo patients.

Adolescent↗
PubMed1990

Mechanism of gallium 67 accumulation in inflammatory tissue.

The present study was undertaken to elucidate the accumulation mechanism of gallium 67 in inflammatory tissue. 67Ga accumulation in inflammatory tissue was observed by macro- and microautoradiogram. Permeability indices were calculated for serum albumin from blood vessels into inflammatory and normal tissue. Neutrophils and macrophages did not play a major role in 67Ga accumulation in the inflammatory tissue because 67Ga could hardly be detected in the sites in which neutrophils were crowded; the accumulation was concentrated in the intercellular space around these cells in the tissue. Permeability indices for inflammatory tissue were much greater than those for normal tissues. It is thought from the present study and previously reported results that 67Ga, together with plasma from permeable blood vessels, readily penetrates the inflammatory tissue and stays there by binding to the acid mucopolysaccharide present in the tissue.

Animals↗
PubMed1990

Accumulation of each element in the lysosome of tumor and liver cells as systematized according to its location in the periodic table.

Hard and borderline acids which were formed by losing electrons from the d-shell accumulated extensively in the lysosomes of tumor and liver with time after administration of these ions. They were bound in these tissues to acid mucopolysaccharides, the mol. wt of which exceed 40,000 Da. Trivalent hard acids which were formed by losing electrons from s- or p-shells accumulated extensively in liver lysosomes, but very little in tumor lysosomes, and were bound in the tissues to the acid mucopolysaccharides with a mol. wt of ca 10,000 Da.

Animals↗
PubMed1990

Biodistribution of 95Nb and 182Ta in tumor-bearing animals and mechanisms for accumulation in tumor and liver.

The biodistribution and binding substances of 95Nb and 182Ta were investigated and compared with other nuclides using tumor-bearing rats and mice. Retention values of 95Nb in tumor tissue were greater than those for 67Ga-citrate, while those for 182Ta were similar to those for 67Ga. The values for these nuclides in the liver and spleen were much smaller than those for 67Ga. However, the values for blood and some soft tissues were much greater than those for 67Ga. The concentrations of 95Nb and 182Ta were more dominant in the connective tissue (especially inflammatory tissue) than in the other categories of tumor tissue. These nuclides accumulated rapidly into the mitochondrial fraction (containing lysosome) of the liver, reaching about 50% after 48 hours, but these nuclides existed relatively uniformly in the tumor cells. The main binding substance of these nuclides in the above tissues was the acid mucopolysaccharide whose molecular mass exceeded 40,000 daltons. Radioactive niobium can be a potential tumor imaging agent. Among radioactive niobiums, 95mNb has physical characteristics (half-life 90 hours, IT decay, 234-keV energy of 100% abundance) suitable for clinical imaging study.

Animals↗
PubMed1990

Tumor uptake and biodistribution of various radiolabels.

42K, 86Rb, 134Cs and 201Tl accumulated in viable tumor tissue and not in necrotic tumor tissue. 22Na, however, accumulated in necrotic tumor tissue. These elements existed almost as free ions in the tissues. The ions of 67Ga, 111In, 169Yb and 167Tm, which are hard acids, were predominant in connective tissue (especially inflammatory tissue) rather than in viable tumor tissue and were not seen in necrotic tumor tissue. These ions were bound to the acid mucopolysaccharide with a molecular weight of about 10,000 dalton in tumor and other soft tissues. The ions of 46Sc, 51Cr, 103Ru, 95Zr, 181Hf, 95Nb, 182Ta and 58Co, which have incomplete d-shells, were much more dominant in connective tissue (especially inflammatory tissue) than in viable and necrotic tumor tissue. They tended to accumulate into the lysosome of malignant tumor cells. They were bound to the acid mucopolysaccharides whose molecular weights exceed 40,000 dalton. The ions of 65Zn and 103Pd, which are soft acids, mainly accumulated in viable tumor tissue.

Animals↗
PubMed1989

Ganglioside GM2 expression on human melanoma cells correlates with sensitivity to lymphokine-activated killer cells.

Ganglioside GM2 is expressed on cell surface membranes of a variety of human malignant cells and has been demonstrated to be immunogenic in humans. We have assessed the role of the antigen GM2 on melanoma cells as a recognition structure for lymphokine-activated killer (LAK) cells. LAK cells were generated by stimulation of non-adherent peripheral blood lymphocytes (PBL) from human donors with recombinant interleukin-2 (IL-2). The selection of target cells was based on GM2 content and included 11 human melanoma cell lines and 2 human leukemia lines. Using a single-cell binding assay, LAK cell binding to target lines expressing high levels of GM2 was significantly greater than to those expressing minimum GM2. This cell-binding was specifically inhibited by addition of purified GM2 but not by other gangliosides. LAK-melanoma cell-binding was also specifically inhibited by anti-GM2 monoclonal antibody (MAb). For further analysis LAK cell lysis of melanoma target cells expressing various amounts of GM2 was assessed. A significant correlation occurred with GM2 expression and LAK cell lysis (p less than 0.025; r = 0.623). Three other gangliosides commonly expressed on human melanoma, GM3, GD3 and GD2, had no correlation with LAK cell lysis. These studies suggest that GM2 on melanoma cells is a marker for LAK cell sensitivity, as well as indicate that GM2 is a potential target recognition structure for human LAK cells.

Antibodies, Monoclonal↗
PubMed1989

Determination of the lysosomal role in tumor accumulation of 67Ga by dual-tracer studies.

The lysosomal role in tumor accumulation of 67Ga was determined by dual-tracer (67Ga and 46Sc) studies. It became clear that 67Ga essentially did not accumulate in the tumor lysosome, and that the lysosome did not play a major role in tumor accumulation of 67Ga. In addition, it was revealed that tumor lysosome was hardly disrupted at all in some phases of fractionation procedures.

Animals↗
PubMed1989

Relation between the location of elements in the periodic table and various organ-uptake rates.

Fifty four elements and 65 radioactive compounds were examined to determine the organ uptake rates for rats 3, 24 and 48 h after i.v. injection of these compounds. They were prepared as carrier free nuclides, or containing a small amount of stable nuclide. Generally speaking, behaviors of K, Rb, Cs and Tl in all the organs were very similar to one another, but they differed from that of Na. Bivalent hard acids were avidly taken up into bone; therefore, uptake rates in soft tissues were very small. Hard acids of tri-, quadri- and pentavalence which were taken up into the soft tissue organs decreased more slowly from these organs than other ions. Soft acids such as Hg2+ were bound very firmly to the component in the kidney. Anions (with few exceptions), GeCl4 and SbCl3 were rapidly excreted in urine, so that the uptake rates in organs were low.

Animals↗