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Biomedical subjects

S Tanabe

Publications and source records attributed to S Tanabe.

At least 37 records · Page 2Linked to original sources

Contamination by persistent organochlorines and butyltin compounds in the west coast of Sri Lanka.

Concentrations of polychlorinated biphenyls (PCBs), dichlorodiphenyl trichloroethane and its metabolites (DDTs), isomers of hexachlorocyclohexane (HCHs), hexachlorobenzene (HCB), chlordane compounds (CHLs) and butyltin compounds (mono-, di- and tributyltin) were determined in biota and sediments collected from locations on the west coast of Sri Lanka. The PCB concentrations found in fish from the Kelani River mouth were higher than those from other Asian developing countries. The pattern of organochlorine accumulation was in the order of PCBs > DDTs > CHLs > HCHs > HCB, and resembled those reported for most developed countries. The accumulation pattern of butyltins in fish was in the order of TBT > DBT > MBT suggesting recent exposure to TBT sources. Total butyltin concentrations found in rabbit fish liver (11-38 micrograms/g wet wt), collected from the Colombo dockyard, could be the highest ever reported for fish in the world.

Animals↗

Caprella watch: a new approach for monitoring butyltin residues in the ocean.

A comparative study on the butyltin levels in various organisms showed that marked bioaccumulation occurs in certain lower trophic levels; i.e. from seawater to phytoplankton and into caprellid amphipods, Caprella spp. Caprella spp., which inhabit algal communities and aquaculture beds in the subtidal zone, are small crustaceans with reduced movement and a life-span of less than 3 months. These characteristics indicate that Caprella spp. may be well-suited for monitoring butyltin residue changes over small spatial and temporal scales. Two groups of organisms, mussels and neogastropods, have been mainly used for monitoring butyltin in shallow water ecosystems. These invertebrates mainly inhabit the intertidal zone where the butyltin levels vary widely depending on the immersion period and exposure to the sea surface microlayer. Monitoring using neogastropods may also over estimate exposures after restrictions on tributyltin, since neogastropods show an irreversible response to residue changes owing to their long life-spans. Thus, we propose usage of Caprella spp. to monitor temporal and spatial changes in baseline concentrations of butyltins.

Animals↗

Concentration and toxic potential of polychlorinated biphenyl congeners in migratory oceanic birds from the North Pacific and the Southern Ocean.

Concentrations of PCBs and their toxic potential were examined in subcutaneous fat of eight albatross and one petrel species collected from the North Pacific and the Southern Oceans. Among all the species analyzed, high PCB levels were found in adult male blackfooted albatross from the North Pacific with the mean value of 92 microg/g wet weight. No significant gender difference in PCB accumulation was observed (P>0.1). The mean PCB levels in Southern Oceanic birds were 1 or 2 orders of magnitude lower than those from the North Pacific albatrosses. A regional-specific accumulation of non-ortho coplanar congeners were observed, most birds from the Southern Ocean had higher IUPAC 169 levels while IUPAC 126 concentrations were higher in those from the North Pacific. The estimated toxic equivalents for black-footed and Laysan albatrosses from the North Pacific were in the same range of some fish-eating birds, which were highly contaminated by PCBs. The correlation between ratio of IUPAC 169/126 concentration and total PCBs concentration indicated the possibility of induction in cytochrome P450 activities in North Pacific albatrosses (P<0.01). The calculated hazard indices indicated that black-footed and Laysan albatrosses inhabiting in the North Pacific had similar threshold levels which were known to cause toxic effects in some populations of fish-eating birds.

Adipose Tissue↗

Distribution of organochlorine pesticides in sediments from Kyeonggi Bay and nearby areas, Korea.

The residues of oragnochlorine pesticides (OCPs) in 62 sediments from Kyeonggi Bay and nearby areas in the west coast of Korea were determined. The concentrations of chlordanes (CHLs) and DDTs showed a distinctive gradient of contamination between inner and outer sites of Incheon North Harbor (INH), whereas hexachlorocyclohexanes (HCHs) were uniformly distributed at most sites studied. The distribution of CHLs and DDTs was strongly correlated with total organic carbon contents in sediments while HCH residue levels were independent. Relationship between contaminant's concentration and environmental factors was analyzed by principal component analysis. Distribution patterns of T-CHLs, T-DDTs, and TOC were similar while those of T-HCHs, mud content, and grain size were similar. The notable contamination by CHLs and DDTs was found in INH where these levels were one or two orders of magnitude higher than other sites. The dominant OCPs in sediments were beta-HCH among HCH compounds, trans-chlordane among CHL compounds, and p,p'-DDD among DDT compounds. The higher concentrations and compositional pattern of OCPs in INH sediments indicate that INH is in the vicinity of the source.

Carbon↗

Accumulation status of persistent organochlorines in albatrosses from the North Pacific and the Southern Ocean.

Current status of contamination by persistent organochlorines (OCs) such as polychlorinated biphenyles (PCBs), dichlorodiphenyl trichloroethane and its metabolites (DDTs), isomers of hexachlorocyclohexane (HCHs), hexachlorobenzene (HCB) and chlordane compounds (CHLs) were examined in 61 individuals belonging to eight albatross species collected from the North Pacific and the Southern Ocean. Generally high OC concentrations were found in albatrosses from the North Pacific than those from the Southern Oceans. Black-footed albatrosses had noticeably high PCBs and DDTs concentrations with mean values of 92 and 33 micrograms/g wet weight in subcutaneous fat, respectively. Among the other OCs, concentration of CHLs was higher than that of HCB in North Pacific albatrosses. HCHs accumulation was the lowest among all the OCs analyzed. Species-specific differences were observed for HCB, CHLs and DDTs in some species in the Southern Ocean. No significant difference of gender and age-related accumulation was observed in total OCs. However, PCB concentrations were higher in mature birds than those from immature ones in the Southern Ocean. Species-specific accumulation patterns of OCs in albatrosses were closely related with their feeding, migration, age and geographical ranges.

Age Factors↗

Arsenic accumulation in the liver tissue of marine mammals.

Arsenic concentrations were determined in livers of 226 individuals representing 16 different marine mammal species to elucidate its accumulation with age, sex, and feeding habits. Arsenic concentrations varied widely among species and individuals, and ranged from < 0.10 to 7.68 micrograms g-1 dry weight. Marine mammals feeding on cephalopods and crustaceans contained higher arsenic concentrations than those feeding on fishes. No significant gender difference in arsenic concentration was found for almost all the species. Also, no apparent trend with age (or body length) in arsenic accumulation was found for most of the species. It was noted that two seal species, Baikal seal and Caspian seal, from landlocked water environments, contained lower arsenic concentrations than the marine species. To our knowledge, this is the first comprehensive study of arsenic accumulation in a wide range of marine mammal species.

Age Factors↗

Systematic status of Hynobius tokyoensis (Amphibia: Urodela) from Aichi Prefecture, Japan: a biochemical survey.

Taxonomic status of a salamander now identified as Hynobius tokyoensis from Aichi Prefecture, Japan, was assessed by allozymic comparisons with its relatives. All three populations of H. tokyoensis from Aichi formed a monophyletic group with populations of H. nebulosus; this group is substantially diverged from a conspecific population from Kanagawa that formed another group with H. lichenatus. In the former group, the population of H. nebulosus from near the type locality was more divergent from the other conspecific populations than were three populations of H. tokyoensis from Aichi. It is quite clear that the salamander from Aichi now identified as H. tokyoensis is genetically much closer to H. nebulosus than to H. tokyoensis from Kanagawa, which is closest geographically to its type locality. This result conforms well to reported results of morphological and genetic studies, and the salamander from Aichi, now called H. tokyoensis, should be identified as H. nebulosus, which is sufficiently diverged from H. tokyoensis to be considered a distinct species.

Algorithms↗

Mast cell chymase expression and mast cell phenotypes in human rejected kidneys.

BACKGROUND: Mast cells (MCs) are known to participate in various types of chronic disease, but their role in chronic renal rejection is poorly understood. Recently, distinct phenotypes of MCs have been described in humans by the demonstration of one protease, chymase. Hence, we questioned whether chymase in MCs could play a role in the pathogenesis of renal rejection in humans. METHODS: We investigated MC chymase expression and MC phenotypes, using immunohistochemical single- and double-staining techniques, in nephrectomy (N = 13) and biopsy (N = 8) specimens of human rejected kidneys. Tissue chymase levels were determined by enzymatic assay for chymase activity. We also examined the association between MC chymase expression and the degree of interstitial fibrosis in these renal allografts. RESULTS: Based on chymase positivity, rejected kidneys were divided into two groups, a chymase-negative [Chy(-)] group and a chymase-positive [Chy(+)] group. Quantitative analysis showed that the number of chymase-positive MCs and tissue chymase levels were significantly higher in the Chy(+) group than in the Chy(-) group. Furthermore, the interstitial fibrotic area in the Chy(+) group was significantly larger than that in the Chy(-) group. Immunodouble staining analysis also demonstrated that a new MC phenotype, positive for chymase but negative for tryptase, was present in the human rejected kidney. CONCLUSIONS: These results show that increased expression of chymase in MCs is related to the severity of interstitial fibrosis in human rejected kidneys.

Adolescent↗

Saccular renal artery aneurysm treated with an autologous vein-covered stent.

A 32-year-old woman underwent an autologous saphenous vein-covered stent deployment for the treatment of a saccular aneurysm on the distal renal artery. Complete exclusion of the aneurysm was immediately obtained. One year after the treatment, remarkable shrinkage of the aneurysm was demonstrated by means of computed tomography, and wide patency of the renal artery and the stent was shown by means of angiography.

Adult↗

Consumption of hypoallergenic flour prevents gluten-induced airway inflammation in Brown Norway rats.

Brown Norway rats were immunized with gluten, and then fed a diet containing hypoallergenic flour or an amino acid mixture. The rats were then made to inhale a solubilized gluten to induce gluten-specific bronchial asthma. The antibody levels in the serum of rats were measured by ELISA, and cell counts were done on cytospin preparations of bronchoalveolar lavage fluid. Body weight was decreased after allergen challenge in rats fed the amino acid mixture but not in rats fed the hypoallergenic flour. Antibody levels in the serum were significantly lower in rats fed hypoallergenic flour than in those fed the amino acid mixture. Differential cell counts in the bronchoalveolar lavage fluid showed that the numbers of eosinophils, lymphocytes, and neutrophils were significantly lower in rats fed the hypoallergenic flour than in those fed the amino acid mixture. These results suggest that hypoallergenic flour actively suppresses the allergic reactions, probably by inducing oral tolerance.

Animals↗

IgE-reactive 60 kDa glycoprotein occurring in wheat flour.

A new IgE-reactive glycoprotein with a molecular size of 60 kDa was isolated from wheat flour. The N-terminal amino acid sequence of the protein was LDPDESEXVTRYFRIR. The 8th amino acid residue would have been Asn to which the peroxidase-type glycochain was attached. The IgE-binding activity of the glycoprotein was rendered negligible by the enzymatic treatment applied for hypoallergenic flour production.

Amino Acid Sequence↗

Specific accumulation and elimination kinetics of tris(4-chlorophenyl)methane, tris(4-chlorophenyl)methanol, and other persistent organochlorines in humans from Japan.

We examined human adipose tissue, liver, and bile from humans in Japan to understand the contamination status, specific accumulation, and elimination of two newly identified environmental contaminants, tris(4-chlorophenyl)methane (TCPMe), tris(4-chlorophenyl)methanol (TCPMOH), and other persistent organochlorines such as polychlorinated biphenyls (PCBs), DDT and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), hexachlorobenzene (HCB), and chlordane compounds (CHLs). TCPMe and TCPMOH concentrations in Japanese human adipose tissue were slightly higher than those reported previously, indicating widespread exposure to these compounds in humans. Elevated residues of PCBs and DDTs are found in adipose tissue and liver. Concentrations in bile strongly correlated with concentrations in adipose fat and liver, which may suggest an equilibration in adipose fat/bile and liver/bile and possible biliary excretion of persistent organochlorines in humans. Composition of the organochlorines accumulated further indicates a metabolic capacity in humans higher than that of marine mammals. We observed age-dependent accumulation for TCPMe, TCPMOH, and other organochlorines, but there were no significant gender differences. p,p'-DDE and TCPMe were estimated to have low biliary excretion rate. Elimination potential of persistent organochlorines may be related to their octanol-water partition coefficient. The relationship between excretion rate and octanol-water partition coefficient may be used to predict the biliary excretion potential of some other lipophilic organochlorines such as dioxins and dibenzofurans in humans. The presence of organochlorines in bile suggests that the hepatic excretory system plays a major role in the elimination of xenobiotics in humans. To our knowledge, this is the first study of accumulation and elimination of TCPMe and TCPMOH in humans.

Adipose Tissue↗

Comparison of the upper gastrointestinal effects of etodolac and aspirin in healthy dogs.

Fifteen healthy castrated male dogs were separated into three treatment groups that were administered etodolac, aspirin and a placebo orally, respectively. All treatments were continued for 28 days. The animals were examined endoscopically on days 0, 3, 7, 10, 14, 17, 21, 24 and 28. There were no gastrointestinal mucosal lesions in either the etodolac or the placebo group, whereas some gastric lesions developed in the aspirin group after day 17. We considered that etodolac could be used for long-term treatments in dogs with fewer side-effects on the gastric mucosa than aspirin.

Animals↗

Seasonal changes in serum total thyroxine, free thyroxine, and canine thyroid-stimulating hormone in clinically healthy beagles in Hokkaido.

The purpose of this study was to evaluate seasonal influences on thyroid hormone levels of healthy outdoor dogs in Hokkaido. We surveyed serum basal total thyroxine (tT4), free thyroxine (fT4), and canine thyroid-stimulating hormone (cTSH) levels, and tT4 levels after administration of TSH for a year. Basal tT4 levels decreased in January, and increased in August and September. fT4 levels increased in January and November. No significant seasonal variation was found in cTSH. tT4 levels after administration of TSH in August and November increased. These results suggested that the thyroid gland may have been activated in November. We should take seasonal variation into consideration when thyroid function is tested.

Animals↗

Changes in serum thyroid hormone levels in newborn calves as a diagnostic index of endemic goiter.

Maximum serum thyroxine (T4) and triiodothyronine (T3) levels of healthy calves were seen at 1 day after birth, and thereafter rapidly decreased until 5 days after birth. They stabilized until 2 weeks after birth, then gradually decreased until 4 weeks after birth. Serum T4 levels of calves with endemic goiter tended to be lower than those of healthy ones, but showed similar levels to those of adult cows. T3 levels of calves with goiter were similar to those of healthy ones, but showed higher variation. T4/T3 ratio of calves with goiter were significantly lower than those of healthy ones and adult cows. While individual levels of serum T4 and T3 at just after birth could not be considered as a diagnostic index, the T4/T3 ratio could be adopted as a diagnostic index of endemic goiter.

Age Factors↗

Reduction of the infectivity of Toxoplasma gondii and Eimeria stiedai sporozoites by treatment with bovine lactoferricin.

Sporozoites of Toxoplasma gondii preincubated with lactoferricin showed decreased activity in penetration of mouse embryonal cells. Mice inoculated with 10(5) sporozoites preincubated with lactoferricin showed a higher survival rate than those inoculated with the same number of untreated sporozoites. Likewise, sporozoites of Eimeria stiedai preincubated with lactoferricin also showed decreased activity in penetration of rabbit hepatobiliary cells. Rabbits inoculated with 10(5) sporozoites preincubated with lactoferricin shed fewer oocysts than those inoculated with the same number of untreated sporozoites. These results indicate that lactoferricin is effective to reduce the infectivity of sporozoites of Toxoplasma gondii and Eimeria stiedai.

Animals↗