Biomedical subjects

T Iida

Publications and source records attributed to T Iida.

At least 541 records · Page 30Linked to original sources

PubMedDate not supplied

Chemiluminescence of adzuki bean and soybean seedlings.

The chemiluminescence of extracts from leguminous seedlings (adzuki bean and soybean) was investigated. In an H(2)O(2)/gallic acid/water extract system, the photon intensities of adzuki bean seedlings were increased after germination and in the hypocotyls it reached a maximum level during the first 4 days of germination. On day 4 after germination, chemiluminescence in the primary leaf part exhibited the strongest intensity. Emission spectra showed a main peak at 510 nm, with shoulders at 660 nm. Mechanical injuries to the stems and cotyledons resulted in about a 1.5- and 6.8-fold increase of chemiluminescence, respectively. In an H(2)O(2)/70% EtOH extract/HRP system, photon intensities increased after germination and reached a maximum level during the first 2 days of germination. On day 4 after germination, chemiluminescence in the root and leaf area was stronger than in any other area. Emission spectra showed a main peak at around 570 nm, with shoulders at around 660 nm. The photon intensities of stems and cotyledons after mechanical injuries resulted in about an 0.72-fold decrease and an 8.8-fold increase in the presence of H(2)O(2) and acetaldehyde (MeCHO), respectively.

Fabaceae↗

PubMedDate not supplied

Imaging of hydroperoxide and hydrogen peroxide-scavenging substances by photon emission.

An imaging system for the hydroperoxide and hydrogen donor was developed by photon emission from the reactive oxygen species-hydrogen donor-KHCO(3)-MeCHO system. Photon intensity (luminance, cd/m(2)) showed a linear correlation with the concentration of some hydroperoxides [hydrogen peroxide (H(2)O(2)), tert-butyl hydroperoxide and methyl ethyl ketone peroxide] and that of hydrogen donors (catechins and anthocyanins). The linear relationship between photon intensity and concentration was observed in polyphenol-rich samples, such as teas, berries and currants. Photon intensity from the H(2)O(2)/polyphenol-rich sample-KHCO(3)-MeCHO system corresponded with H(2)O(2)-scavenging activity, rather than with polyphenol contents. It is possible to classify hydrogen donor species according to absorption features using spectral analysis (gallic acid, E(max) 645 nm, catechins, E(max) 610 nm; anthocyanins, E(max) 690-700 nm). This method is a simple and sensitive detection system for hydroperoxide- and H(2)O(2)-scavenging substances.

Acetaldehyde↗

PubMedDate not supplied

Preparation of glycine-conjugated bile acids and their gas/liquid chromatographic analysis on an aluminum-clad flexible fused silica capillary column.

This paper describes a method for the direct gas/liquid chromatographic (GC) analysis of 46 glycine-conjugated bile acids, which differ from one another in the number, position and configuration of the hydroxyl groups at positions C-2, C-3, C-4, C-6, C-7 and/or C-12. Free bile acids were converted quantitatively on a micro scale to ethyl ester-trimethylsilyl (Et-TMS) and methyl ester-dimethylethylsilyl (Me-DMES) ether derivatives of the corresponding glycine conjugates. The Et-TMS and Me-DMES ethers of the glycine conjugates were chromatographed on an aluminum-clad flexible fused silica capillary column coated with a thin film (0.1 micron) of chemically bonded and cross-linked methylpolysiloxane. Relative retention time (RRT) and methylene unit (MU) values were determined for the 46 compounds and their GC behaviour was discussed. The derivatization procedure and the retention data would be useful for the direct GC identification of unknown glycine-conjugated bile acid mixtures extracted from biological samples.

Bile Acids and Salts↗

PubMedDate not supplied

High performance liquid chromatographic determination of trimethoprim residues in egg yolk and albumen in a feeding experiment.

In a feeding experiment, the residues of trimethoprim (TMP) in egg yolk and albumen were determined by high performance liquid chromatography (HPLC). Laying hens were divided into four groups. The first group was designated as control and fed with TMP free diet during the experimental period. The second, third and fourth groups were administered with the feeds containing 4 p.p.m., 16 p.p.m. and 56 p.p.m. TMP, respectively, for 19 days and, thereafter, fed with TMP free diet. TMP was mainly found in yolk in all the three administered levels. In the medication period, the average concentration of TMP in the yolk of the second, third and fourth groups was 0.05, 0.25, and 0.90 p.p.m., respectively. After withdrawal of medication, the residues of TMP in yolk in the second, third and fourth groups decreased below the detection limit at 0.02 p.p.m. on days 4, 9, and 11, respectively.

Animals↗

PubMedDate not supplied

Effects of highly toxic organochlorine compounds retained in human body on induction of sister chromatid exchanges in cultured human lymphocytes.

In this study, we investigated the effect of mixture of the organochlorine compounds, which very resembled their contamination of healthy Japanese people in its composition, on the induction of sister chromatid exchanges (SCEs) in human whole-blood cultures in order to clarify their genotoxicity as a whole. The following results were obtained. Regardless of the presence or absence of 7,8-benzoflavone (ANF) in the blood culture system, we could observe a fairly good dose-response relationship between the concentration of the mixture of organochlorine compounds and the induction of SCEs/cell. In particular, we found that 50% effective concentration of the mixture of the organochlorine compounds was considered to be only about 3 times greater level over the average concentration in the healthy people, namely 70ppt as 2,3,7,8-TCDD, in the absence of ANF and about 8 times more than that in the presence of ANF.

Adult↗

PubMedDate not supplied

Effects of donor age and contamination level of dioxins and related chemicals on frequency of sister chromatid exchanges in human lymphocytes cultured in vitro.

Frequencies of sister chromatid exchanges (SCEs) of human lymphocytes in control (DMSO treated) and 7,8-benzoflavone (ANF) treated cultures were measured in 39 healthy Japanese people and examined in connection with donor age. Both the control (baseline) and ANF induced SCE rates were significantly enhanced with age and highly positive correlation was observed between them. Therefore, in vivo aging seemed to have some effects on the frequencies of SCEs in human lymphocytes cultured in vitro. Concentrations of PCDDs, PCDFs and Co-PCBs in the blood and sebum of face were determined in the same Japanese subjects. Significantly positive correlation was observed between the blood and sebum in their total TEQ levels. Hence, PCDDs, PCDFs and Co-PCBs, which have been contaminating human bodies, are considered proportionally excreted from the sebum of face or body. Their total TEQ concentrations were also meaningfully increased with donor age in the sebum of face as well as in the blood. Either the baseline or ANF induced SCE frequencies was not enhanced with the total TEQ levels in the blood. Therefore, background levels of their contamination seem not to affect the SCE rates of the lymphocytes in the control and ANF treated cultures.

Adult↗

PubMedDate not supplied

Comparison between "Yusho" patients and healthy Japanese in contamination level of dioxins and related chemicals and frequency of sister chromatid exchanges.

Highly toxic organochlorine chemicals such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (CoPCBs) were determined in the peripheral blood and sebum from the face of 16 "Yusho" patients of about 27 yr after the outbreak of Yusho accident, and 39 healthy Japanese people. The mean total toxic equivalent (TEQ) levels of PCDDs, PCDFs and CoPCBs in the blood were still about seven times higher in Yusho patients than in healthy Japanese at the age of 45 yr and more. The sebum excretion of these chemicals seemed proportional to their blood levels in Yusho patients. These toxic chemicals, however, did not enhance frequencies of sister chromatid exchanges (SCEs) in the control and 7,8-benzoflavone (ANF) treated cultures in Yusho patients. Hence, no significant difference was observed in the mean SCE rates between the Yusho patients and general Japanese people of more than 45 yr of age. In this study, the number of Yusho patients examined is limited, so further large-scale investigations are needed to get more conclusive results concerning the genotoxic potency such as SCE induction.

Adult↗

PubMedDate not supplied

Effects of contamination level of dioxins and related chemicals on thyroid hormone and immune response systems in patients with "Yusho".

Effects of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (Co-PCBs) on thyroid hormone and immune response systems were examined in 16 Yusho patients at about 30 years after the outbreak of the Yusho accident. Their toxic equivalent (TEQ) levels in the blood were 27.8-1048.5 pg/g fat with the median level of 222.4 pg/g fat, which was about seven times higher than that of healthy Japanese people. Even at such high blood TEQ concentrations, they seemed not to affect the serum levels of thyroid hormones, thyroid stimulating hormone (TSH), immunoglobulins (A, G and M), autoantibodies (antinuclear antibody, rheumatoid and lupus erythematosus (LE) factors), and lymphocyte subsets in the blood. However, positive rates of rheumatoid factor were considered to increase in higher blood TEQ groups. This investigation was done using rather small number of Yusho patients, so further large-scale investigations are needed to get more conclusive findings concerning their effects on thyroid hormone and immune response systems.

Adipose Tissue↗

PubMedDate not supplied

Postnatal exposure to chlorinated dioxins and related chemicals on lymphocyte subsets in Japanese breast-fed infants.

Effects of postnatal exposure to polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (Co-PCBs) on lymphocyte subpopulations were investigated in the peripheral blood of 36 breast-fed Japanese babies. As a result, estimated total intakes of these chemicals in toxic equivalent quantity (TEQ) converted into 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) equivalents from the breast milk positively and negatively correlated with the respective percentages of CD4+ and CD8+ lymphocytes in the blood of breast-fed babies. Consequently, the ratios of CD4+ to CD8+ T cells showed significant increasing tendency with the estimated total TEQ intakes. Therefore, our study suggests that exposure to background levels of the highly toxic organochlorine compounds through the breast milk influences the human neonatal immune system.

Adult↗

PubMedDate not supplied

Postnatal exposure to chlorinated dioxins and related chemicals on thyroid hormone status in Japanese breast-fed infants.

Effects of postnatal exposure to polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (Co-PCBs) on thyroid hormone status were studied in the peripheral blood of 36 breast-fed Japanese infants. Estimated total intakes of these chemicals in toxic equivalent quantity (TEQ) converted into 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) from the breast milk significantly and negatively correlated with the levels of triiodothyronine (T3) and thyroxine (T4) in the blood of breast-fed babies. Therefore, exposure to background levels of the highly toxic organochlorine chemicals through the breast milk may cause some effects on thyroid hormone status in Japanese infants.

Adult↗

PubMedDate not supplied

NADPH and NADH serve as electron donor for the superoxide-generating enzyme in tilapia (Oreochromis niloticus) neutrophils.

NADPH oxidase has been identified as the superoxide-generating enzyme in fish neutrophils. To clarify the electron-donating ability of this enzyme, we examine the requirement of NADPH as the electron donor in superoxide generation in tilapia (Oreochromis niloticus) neutrophils using CLA-dependent chemiluminescence (CL). Phorbol ester-induced CL responses were terminated upon the addition of a detergent, Renex-30. The addition of graded amounts of NADPH or NADH restored the CL in a dose-dependent manner. The restoration of CL was completely eliminated by superoxide dismutase, suggesting that the restored CL was due to superoxide generation. NADPH tended to have a greater effect than NADH on the CL responses of tilapia neutrophils.

Animals↗

PubMedDate not supplied

Kinetics of oxygen metabolism during respiratory burst in Japanese eel neutrophils.

Two oxygen radicals, superoxide and hydrogen peroxide, were measured by ferricytochrome C reduction and scopoletin fluorescent assays to investigate oxygen metabolism during the respiratory burst in Japanese eel neutrophils. Maximal superoxide production was obtained using 0.1 microgram/mL of PMA. Oxygen consumption was almost equivalent to superoxide production, indicating that the consumed oxygen was almost fully converted to superoxide in eel neutrophils. Hydrogen peroxide production was approximately half that of oxygen consumption or superoxide production in neutrophils elicited by killed bacteria or casein. The amounts of superoxide and hydrogen peroxide production, by neutrophils elicited by irritants, were about 11.5 and 5.0 nM/10(7) cells/ min, respectively, which were significantly higher than those of unelicited neutrophils (2.4 and 0.3 nM/10(7) cells/min, respectively).

Anguilla↗

PubMedDate not supplied

Evidence for the existence of cytochrome b558 in fish neutrophils by polyclonal anti-peptide antibody.

When western blotting analysis of Japanese eel neutrophil lysate was performed using antibody against the synthetic peptide corresponding to the carboxyl terminal region of human cytochrome b558 large subunit, a broad band was specifically detected at approximately 90 kDa. The antibody recognized the epitope present in eel neutrophils only after the cells were permeabilized with detergent. These results indicate that the large subunit of cytochrome b exists in fish neutrophils and the epitope is exposed to the cytoplasmic side of membrane, and suggest that cytochrome b is conserved across species.

Animals↗

PubMedDate not supplied

Antitumor agents. 49 tricin, kaempferol-3-O-beta-D-glucopyranoside and (+)-nortrachelogenin, antileukemic principles from Wikstroemia indica.

Bioassay-directed isolation of the antitumor extract of Wikstroemia indica (Thymelaeaceae) has led to the characterization of tricin, kaempferol-3-O-beta-D-glucopyranoside, and (+)-nortrachelogenin as the major antileukemic constituents. In addition, daphnoretin was identified as the potent antitumor principle in vivo against the Ehrlich ascites carcinoma growth in mice.

Animals↗

PubMedDate not supplied

Whole-body positron emission tomography and tumor marker CA125 for detection of recurrence in epithelial ovarian cancer.

We evaluated the clinical role of the combination of positron emission tomography (PET) with F-18 fluorodeoxyglucose (FDG) and tumor marker CA125, in the detection of recurrence after initial therapy for epithelial ovarian cancer. The indication is the cases that cannot be confirmed the recurrence by conventional imaging modalities. Ninety patients underwent PET and computed tomography, including the measurement of specific tumor markers. FDG-PET confirmed recurrence in 46 patients (51%), and the recurrent site was confirmed by PET alone in 17 (37%). PET had high sensitivity for detecting both intraperitoneal and retroperitoneal metastases (93.9 and 92.9%, respectively). PET imaging was able to detect normal-sized metastases in the lymph nodes in 14 (50%) of the 28 patients with retroperitoneal metastasis. PET could show 87.5% positive rate of recurrent patients with asymptomatic rise of CA125 who had no sign of recurrence by conventional imaging methods. Of the 46 recurrent patients, 41 (89%) had specific elevated titers of CA125 at the first treatment. PET imaging was able to detect recurrence at relatively low titers (a median 68 U/mL) of CA125. In 8 (19.5%) of these 41 patients, recurrence with normal CA125 levels could be confirmed only by PET. The sensitivity of the combination of PET and CA125 was 97.8% with only one false-negative case. The combination of FDG-PET and CA125 titer is useful for the accurate detection of recurrence.

Adenocarcinoma↗

PubMedDate not supplied

Phylogenetic identification of hypermastigotes, Pseudotrichonympha, Spirotrichonympha, Holomastigotoides, and parabasalian symbionts in the hindgut of termites.

The phylogenetic diversity of parabasalian flagellates was examined based on the sequences of small subunit ribosomal RNA genes amplified directly from the mixed population of flagellates in the hindgut of lower termites. In total, 33 representative sequences of parabasalids were recovered from eight termite species. Fluorescent-labeled oligonucleotide probes specific for certain sequences were designed and used for the in situ identification of parabasalian species by whole-cell hybridization. The hypermastigotes, Pseudotrichonympha grassii, Spirotrichonympha leidyi, and Holomastigotoides mirabile in the hindgut of Coptotermes formosanus, and Spirotrichonympha sp. and Trichonympha spp. in Hodotermopsis sjoestedti were identified. In the phylogenetic tree constructed, the sequences from the termites were dispersed within the groups of known members of parabasalids, reflecting the presence of diverse parabasalids in the hindgut of termites. There were three paraphyletic lineages of hypermastigotes represented by Pseudotrichonympha, Trichonympha, and Spirotrichonympha, in agreement with the morphology-based taxonomic groups. The analysis of the tree-root suggested that the Pseudotrichonympha group is the most probable ancient lineage of parabasalids and that the Trichonympha group is the secondly deep-branching lineage. The Spirotrichonympha group and the Trichomonadida may have emerged later.

Animals↗

PubMedDate not supplied

Immunohistochemical study of surgically excised choroidal neovascular membranes.

We carried out an immunohistochemical investigation of the choroidal neovascular membranes from 12 eyes surgically excised as a result of age-related macular degeneration (n = 6) or idiopathic choroidal neovascularization (n = 6). Immunohistochemical staining was performed with antibodies specific for basic transcriptional element binding protein-2, actin or smooth muscle cell 1. In all membranes, the endothelial cells and stromal components around the vessels were immunoreactive for expression of basic transcriptional element binding protein-2, while immunoreactive expression of actin and smooth muscle cell type 1 was found in the surrounding stromal cells. These results suggest that basic transcriptional element binding protein-2, a zinc finger transcription factor, may contribute to the establishment of the choroidal neovascularization observed in the pathogenesis of age-related macular degeneration and idiopathic choroidal neovascularization.

Actins↗

PubMedDate not supplied

Multidrug-resistant enteroaggregative Escherichia coli associated with persistent diarrhea in Kenyan children.

To study the association of multidrug-resistant enteroaggregative Escherichia coli with persistent diarrhea in Kenyan children, stool specimens were obtained from 862 outpatients under 5 years of age from July 1991 to June 1993. E. coli O44 was identified as the sole bacterial pathogen in four patients experiencing at least 14 days of fever, vomiting, and diarrhea. Disk diffusion testing showed E. coli O44 resistance to tetracycline, ampicillin, erythromycin, trimethoprim-sulphamethoxazole, and amoxicillin/clavulanate and sensitivity to chloramphenicol, nalidixic acid, azithromycin, and cefuroxime. Further studies are needed to clarify the epidemiology, clinical spectrum, and pathogenesis of enteroaggregative E. coli infection.

Anti-Bacterial Agents↗