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Biomedical subjects

S Tanabe

Publications and source records attributed to S Tanabe.

At least 199 records · Page 11Linked to original sources
PubMed1996

Distribution of 11q23 breakpoints within the MLL breakpoint cluster region in de novo acute leukemia and in treatment-related acute myeloid leukemia: correlation with scaffold attachment regions and topoisomerase II consensus binding sites.

A major unresolved question for 11q23 translocations involving MLL is the chromosomal mechanism(s) leading to these translocations. We have mapped breakpoints within the 8.3-kb BamHI breakpoint cluster region in 31 patients with acute lymphoblastic leukemia and acute myeloid leukemia (AML) de novo and in 8 t-AML patients. In 23 of 31 leukemia de novo patients, MLL breakpoints mapped to the centromeric half (4.57 kb) of the breakpoint cluster region, whereas those in eight de novo patients mapped to the telomeric half (3.87 kb). In contrast, only two t-AML breakpoints mapped in the centromeric half, whereas six mapped in the telomeric half. The difference in distribution of the leukemia de novo breakpoints is statistically significant (P = .02). A similar difference in distribution of breakpoints between de novo patients and t-AML patients has been reported by others. We identified a low- or weak-affinity scaffold attachment region (SAR) mapping just centromeric to the breakpoint cluster region, and a high-affinity SAR mapping within the telomeric half of the breakpoint cluster region. Using high stringency criteria to define in vitro vertebrate topoisomerase II (topo II) consensus sites, one topo II site mapped adjacent to the telomeric SAR, whereas six mapped within the SAR. Therefore, 74% of leukemia de novo and 25% of t-AML breakpoints map to the centromeric half of the breakpoint cluster region map between the two SARs; in contrast, 26% of the leukemia de novo and 75% of the t-AML patient breakpoints map to the telomeric half of the breakpoint cluster region that contains both the telomeric SAR and the topo II sites. Thus, the chromatin structure of the MLL breakpoint cluster region may be important in determining the distribution of the breakpoints. The data suggest that the mechanism(s) leading to translocations may differ in leukemia de novo and in t-AML.

Acute Disease↗
PubMed1996

A major wheat allergen has a Gln-Gln-Gln-Pro-Pro motif identified as an IgE-binding epitope.

The minimum primary structure of the IgE-binding epitope in wheat gluten was determined as Gln-Gln-Gln-Pro-Pro. The N-terminal glutamine and the two proline residues were essential for epitopic function. The occurrence of the second glutamine residue and acetylation of the N-terminal amino group were found to exert some auxiliary functions, whereas only a lesser contribution was expected for the third glutamine residue. It has also been confirmed that acetyl-Gln-Gln-Gln-Pro-Pro bound to wheat-specific IgE antibodies in the sera of patients allergic to wheat, although it did not induce histamine release from the basophils of these patients. Taken together, we concluded that the Gln-Gln-Gln-Pro-Pro motif constituted an IgE-binding rather than immunogenic epitope and also that acetyl-Gln-Gln-Gln-Pro-Pro might act as a hapten capable of binding to specific IgE molecules. The possibility exists that this peptide will have practical application to therapy for or prevention of wheat-sensitive allergy.

Allergens↗
PubMed1996

Analysis of the t(6;11)(q27;q23) in leukemia shows a consistent breakpoint in AF6 in three patients and in the ML-2 cell line.

The t(6;11)(q27;23) is one of the most common translocations observed in patients with acute myeloid leukemia (AML). The translocation breakpoint involves the MLL gene, which is the human homolog of the Drosophila trithorax gene, at 11q23 and the AF6 gene at 6q27. Reverse transcriptase-polymerase chain reaction (RT-PCR) using an MLL sense primer and an AF6 antisense primer detected the MLL/AF6 fusion cDNA from three leukemia patients with the t(6;11) [two AML and one T-acute lymphoblastic leukemia (ALL)] and one cell line. The fusion point in the AF6 cDNA from these cases is identical, regardless of the leukemia phenotype. The ML-2 cell line, which was established from a patient with AML that developed after complete remission of T-cell lymphoma, has retained an 11q23-24 deletion from the lymphoma stage and has acquired the t(6;11) with development of AML. The ML-2 cells have no normal MLL gene on Southern blot analysis, which indicates that an intact MLL gene is not necessary for survival of leukemic cells.

Adolescent↗
PubMed1996

Cytochalasin-E-Resistant Mutants of Coprinus cinereus: Isolation and Genetic, Biochemical, and Cytological Analyses

We first obtained a cytochalasin-E supersensitive strain (CES14) of the basidiomycete Coprinus cinereus and then isolated 1000 revertants of CES14, expecting that at least some of the revertants have defects in the functions of actin filaments. Microscopic examination revealed that three of the revertants lack septa in their hyphae. Of the 1000 revertants, 18 including the 3 septumless strains were genetically analyzed. In 11 of the 18 revertants, reversion was due to extragenic suppressor mutations of ces14. Ten of the 11 mutations were in the same locus designated cer1, while the locus of the remaining mutation, which inhibits septum formation, could not be determined because of its failure to mate with any other cer1 strains. In one (CES14R42) of the cer1 mutants, actin appeared to be altered in the affinity to actin antibody in Western blotting after isoelectric focusing, suggesting that cer1 is a gene encoding actin. Phenotypic examination revealed that the 10 cer1 mutations all confer resistance to cytochalasin-E and that two of the cer1 mutations, both of which block septation, inhibit the formation of the actin ring.

Journal Article↗
PubMed1996

Increased tenascin expression is an early feature of the development of transplant renal arteriopathy in humans.

Transplant renal arteriopathy (TRA) is a major obstacle to the long-term survival of human renal allografts. Tenascin (TN) is an extracellular matrix glycoprotein associated with cell growth and differentiation. We investigated TN expression in intrarenal arteries with TRA, in association with cellular components, with phenotypic expression of smooth muscle cells (SMC) and with fibronectin expression. Ten renal allografts that had been removed due to rejection were available. Monoclonal antibodies against SMC, macrophages, T cells, B cells, fibronectin, and TN were used. In the early stages, medial SMC showed a de-differentiated phenotype and the neointima consisted largely of T cells and macrophages. At these stages, increased expression of TN was observed in the media. In later stages, the neointima consisted almost entirely of SMC of a differentiated phenotype and no TN expression was found. Up-regulation of TN may play a role in the migration and phenotypic modulation of SMC at an early stage of TRA in humans.

Actins↗
PubMed1996

Accumulation pattern of butyltin compounds in dolphin, tuna, and shark collected from Italian coastal waters.

Tributyltin (TBT) and its breakdown products, mono-(MBT) and dibutyltin (DBT) were determined in bottlenose dolphin (Tursiops truncatus), bluefin tuna (Thunnus thynnus thynnus) and blue shark (Prionace glauca) collected from the Italian coast of the Mediterranean Sea in 1992-1993. Concentrations of total butyltin (BTs) in the liver of dolphin (1,200-2,200 ng/g wet wt) were an order of magnitude higher than in the blubber (48-320 ng/g wet wt). TBT was the predominant butyltin species in the blubber while DBT accounted for an higher proportion in the liver of dolphins. Butyltin concentrations in bluefin tuna were lower than those in dolphins, with TBT highest in the muscle and DBT in the liver. Concentrations of BTs in blue sharks were lower than those in dolphin and tuna, with kidney having the highest concentrations. TBT was the predominant form of butyltin derivatives in all the tissues of shark. Accumulation of butyltin compounds in liver/kidney seems to be associated with the presence of proteins such as glutathione.

Adipose Tissue↗
PubMed1996

Distribution, biomagnification, and elimination of butyltin compound residues in common cormorants (Phalacrocorax carbo) from Lake Biwa, Japan.

Concentrations of butyltin compounds (BTs) were determined in various body tissues of common cormorants (Phalacrocorax carbo) collected from the Lake Biwa, Japan. Elevated concentrations of butyltins were detected in the feathers of cormorants. Among other organs and tissues, butyltin levels were also higher in the kidney (290+/-150 ng/g) and liver (270+/-260 ng/g), ranging from 115 to 544 ng/g and 142 to 1007 ng/g (wet wt basis), respectively. The accumulation of BTs in cormorant bodies was in the order of MBT>DBT>TBT and their organ specific burdens were in the order of muscle>/=feathers>skin>liver>rest of the tissues and organs. The higher levels of BTs residues in feather suggested the excretion of about one fourth of their body burden during a complete molting cycle, which has been a natural detoxification mechanism in these birds. Based on the whole body concentrations of BTs in cormorants (42-160 ng/g wet wt) and fish (10-55 ng/g wet wt) biomagnification factors were assessed to be in the range of 1.1-4.1. To our knowledge, this is the first fundamental study to substantially indicate the contamination and kinetics of BTs in wild birds.

Animals↗
PubMed1996

Metal accumulation in tissues of seabirds from Chaun, northeast Siberia, Russia.

Concentrations of four essential elements (Fe, Mn, Zn, and Cu) and two toxic metals (Cd and Hg) were determined in selected tissues of 11 seabird species collected in Chaun, northeast Siberia. In oldsquaw, arctic tern and herring gull, zinc concentrations were correlated with Cd concentrations. Cadmium concentrations in all the species were highest in kidney and Hg in liver. Cd levels in the liver and kidney of herring gulls were higher than those observed from other breeding areas. Similarly, Hg concentrations were also high in the liver of herring gull. High concentrations of Cd and Hg found in some birds from Chaun might have arisen from exposure on migration.

Journal Article↗
PubMed1996

Severe hypertension and cardiac failure associated with neuroblastoma: a case report.

The authors report on 3-year-old-girl with neuroblastoma complicated by severe hypertension and cardiac failure. She had cardiomegaly and pleural and pericardial effusions. Echocardiogram showed left ventricular hypertrophy and decrease of the left ventricular ejection fraction to 0.36 (normal > .40). Abdominal computed tomographic scan indicated a 7 x 7-cm tumor in the left suprarenal area. There was a marked increase in catecholamines and metabolites in her body fluids. After hypertension was controlled with doxazosin (a long-acting alpha 1 adrenergic blocker), her cardiac function gradually improved. A tumor was surgically removed and diagnosed as a poorly differentiated ganglioneuroblastoma. Preoperative differentiation between neuroblastoma and pheochromocytoma was not possible on the basis of catecholamine analysis or imaging studies including computed tomography scan and magnetic resonance imaging. It is important to control hypertension quickly in the patients with catecholamine-induced cardiomyopathy to facilitate surgical intervention for diagnosis and treatment.

Adrenergic alpha-Antagonists↗
PubMed1996

ZTTA, a postproline cleaving enzyme inhibitor, improves cerebral ischemia-induced deficits in a three-panel runway task in rats.

We investigated the effect of N-benzyloxycarbonyl-thioprolyl-thioprolinal-dimethylaceta l (ZTTA), a novel postproline cleaving enzyme (prolyl endopeptidase, PPCE) inhibitor, on the in vitro activity of rat brain PPCE and memory impairment induced by cerebral ischemia. ZTTA noncompetitively inhibited rat brain PPCE (ki = 2.9 microM). Cerebral ischemia for 5 min increased the number of errors in a working memory task with a three-panel runway paradigm. ZTTA at 6 mg/kg, administered immediately after blood flow reperfusion, significantly reduced the increase in working memory errors expected to occur 24 h after 5 min of ischemia. The antiamnesic action of ZTTA may be ascribable to a neuroprotective effect on the central nervous system due to some neuropeptides that are substrates of PPCE in the brain.

Animals↗
PubMed1996

Trace element accumulation in Baikal seal (Phoca sibirica) from the Lake Baikal.

Trace element concentrations (Fe, Mn, Zn, Cu, Pb, Ni, Cd, Co and Hg) were determined in 60 Baikal seals and in fishes collected from Lake Baikal in 1992. Low levels of Hg and Cd were found in Baikal seals in comparison with those of marine mammals and it was due to their low concentrations in dietary fish. These results suggest that pollution by Hg and Cd was low in Lake Baikal and these toxic elements were unlikely to be the causative factors for mass mortality of Baikal seal in 1987-1988. Significant correlation of Hg concentration between hair and internal tissues suggested the use of hair for Hg monitoring in pinnipeds. Among essential elements, higher Fe and lower Cu levels were specifically found in the liver of Baikal seal. The noticeable accumulation of essential elements might be related to the unique and specific environment of Lake Baikal.

Journal Article↗
PubMed1996

Specific accumulation of mercury and selenium in seabirds.

Total mercury (T-Hg), methyl mercury (MeHg) and selenium (Se) concentrations were determined to elucidate the relationship between Hg and Se levels in the liver of 10 seabird species. Highest concentrations of T-Hg (mean 267 microg/g dry wt), MeHg (mean 25.5 microg/g dry wt) and Se (mean 113 microg/g dry wt) were in the liver of black-footed albatross (Diomedea nigripes). An equivalent molar ratio of 1:1 between T-Hg and Se was found in the liver of individuals which contain over 100 microg Hg/g. However, such a relationship was unclear in other individuals which had relatively low Hg levels. This suggests that Se plays a role in Hg detoxification for those individuals with high Hg. In seabird tissues, Hg and Se levels should be a most important factor determining the relationship between Hg and Se, and fluctuation of Hg burden through molting and the species-specific demethylation capacity would also influence their relationships.

Journal Article↗
PubMed1996

Modification of wheat flour with bromelain and baking hypoallergenic bread with added ingredients.

Based on the wheat glutenin IgE-binding epitope, Gln-Gln-Gln-Pro-Pro, a practical method is proposed for the production of hypoallergenic wheat flour. Bromelain was found effective for decomposing the epitope structure. In practice, soft flour was mixed with water dissolving bromelain and the mixture was incubated at 37 degrees C for 4 h. The result of IgE-ELISA (enzyme-linked immunosorbent assay) suggested negative allergenicity. A mixture of bromelain-modified flour, glucose, citric, acid, a surfactant and sodium hydrogen carbonate was baked to produce hypoallergenic bread, resembling English muffins.

Amino Acid Sequence↗
PubMed1996

Effect of supplemental lactoferrin with ferrous iron on iron status of newborn calves.

Data for 18 male and 18 female calves, born from primiparous and multiparous cows, were collected to determine the effect of supplemental lactoferrin and FeSO4 for 5 d after parturition on the Fe status of calves. Dietary treatments were 1) untreated, 2) 40 mg of Fe/d as FeSO4, and 3) 40 mg of Fe as FeSO4 plus 5 g of lactoferrin/d. Blood hematocrit and hemoglobin of calves born from primiparous cows at d 1 of age were lower than those of calves born from multiparous cows, but not different from those of their dams. Blood hematocrit and hemoglobin of male calves at d 1 of age were lower than those of female calves. Plasma Fe of primiparous cows at parturition was lower than that of multiparous cows, but plasma Fe of calves was not affected by parity of dam and sex of calf. Blood hematocrit and hemoglobin of untreated calves decreased from 1 to 10 d of age. Blood hematocrit and hemoglobin of calves treated with Fe of Fe plus lactoferrin increased from 2 to 10 d of age. Blood hematocrit and hemoglobin of calves treated with Fe plus lactoferrin were higher than those of calves treated with Fe at d 6 of age. Plasma Fe of calves treated with Fe or Fe plus lactoferrin increased temporarily at d 2 of age. Plasma Fe of calves treated with Fe plus lactoferrin at d 2 of age was lower than that of calves treated with Fe, but, at d 6 and 10 of age, plasma Fe of calves treated with Fe plus lactoferrin were higher.

Animals↗
PubMed1996

A case of calcification of the cervical ligamentum flavum.

We report a case of cervical myelopathy caused by the calcification of the cervical ligamentum flavum. A 42-year-old woman with gait disturbance and an episode of dysuria was transferred to our hospital on June 30, 1994. Neurological examination revealed only a mild right hemiparesis. A plain neck X-ray and a tomogram revealed a nodular calcification in the posterior part of the spinal canal at the level of C5/6. Three dimensional computed tomography clearly demonstrated that the mass consisted of three nodular structures on the vertebral lamina. Magnetic resonance images demonstrated severe compression of the spinal cord by the mass whose intensity was low. The mass was removed en bloc together with the ligamentum flavum and C5 and C6 lamina. The mass showed no continuity to the dura mater. The calcification was confined within the ligament. The patient's neurological deficits were resolved two weeks after the surgery. X-ray diffraction study demonstrated the component of the mass was found to be pure hydroxyapatite. Clinical features of calcification of the ligamentum flavum are reviewed from 85 reported cases including ours, and the difference between this calcification and the ossification of the ligament is emphasized. Calcification of the ligamentum flaum is a distinct clinical entity.

Adult↗
PubMed1996

[A case report of pulmonary blastoma--well differentiated fetal adenocarcinoma].

We report a pulmonary blastoma lacking sarcomatous features in 33-year-old woman. Abnormal shadow was detected in the right upper field in a routine chest X-ray film. The preoperative imaging films showed a 4 x 4 cm, well-circumscribed solid tumor in S3 of the right lung. The preoperative clinical diagnosis of primary lung cancer was considered. The operative findings showed that an elastic hard tumor, 5 cm in diameter, was localized in S3 of the right lung and partially contacted the middle lobe. Right upper and middle lobe resection was performed with lymph node dissection. The postoperative diagnosis was pulmonary blastoma, well differentiated fetal lung (= WDFA). It is considered that the degree of the malignancy of WDFA is lower and the prognosis of WDFA is better than conventional pulmonary blastoma (= biphasic blastoma). There are not available treatments except for surgical resection. It is suggested that it necessary to collect as many cases as possible, to make definite classifications and to examine the clinical course and prognosis of pulmonary blastoma.

Adenocarcinoma↗
PubMed1996

[Clinicopathological findings in symptomatic Rathke's cleft cyst: correlation between enhancement effects on MRI and histopathology of the cyst wall].

We have studied MR images and the histopathology of eight patients with symptomatic Rathke's cleft cysts. Six cases showed visual disturbance and two showed galactorrhea. In five, the cyst fluid had low signal intensity on T1-weighted images and high intensity on T2-weighted images; in 2, the cyst fluid had high intensity on both T1 and T2-weighted images; in 1, the cyst fluid had high intensity on T1-weighted images and low intensity on T2-weighted images. Enhancement of the cyst wall by Gd-DTPA was able to be distinguished in six cases: two patients showed no enhancement, two showed thin enhancement and the remaining two, thick enhancement. Fluid aspiration and total resection of the cyst wall was performed in all patients (three cases by the transcranial approach and five by the transsphenoidal approach). Normal pituitary glands were found in all cases during the operations. Histopathologically, ciliated epithelium with goblet cells was recognized in three cases. Non-ciliated epithelium was recognized in the other five. Stratified squamous component was recognized in one case and secondary inflammation, in another. Normal pituitary tissue was recognized in five cases. Immunohistochemically, ciliated and non-ciliated epithelium was successfully stained for detecting antibody against epithelial membrane antigen and/or carcinoembryonic antigen. Two cases with no enhancement of the cyst wall by Gd-DTPA showed only ciliated epithelium. Two cases with thin enhancement of the cyst wall had single layer epithelium with normal pituitary tissue. Two cases with thick enhancement of the cyst wall showed single layer epithelium with its stratified squamous component or with secondary inflammation. A close relationship was suggested between the enhancement effect on MRI and histopathology of the cyst wall.

Adult↗