Biomedical subjects

M Eguchi

Publications and source records attributed to M Eguchi.

At least 55 records · Page 3Linked to original sources

PubMed2000

Giant noninflammatory and nonatherosclerotic coronary arterial aneurysm in the left main trunk assessed by intravascular ultrasound imaging--a case report.

A case of a giant noninflammatory and nonatherosclerotic coronary arterial aneurysm in the left main trunk of a 69-year-old female is reported. Preoperative intravascular ultrasound (IVUS) images were helpful for visualizing the morphologic and histologic features of the coronary aneurysm. They were also useful for determining the etiologic background and surgical procedure.

Aged↗

PubMed2000

MLL-CBP fusion transcript in a therapy-related acute myeloid leukemia with the t(11;16)(q23;p13) which developed in an acute lymphoblastic leukemia patient with Fanconi anemia.

We describe a boy with Fanconi anemia (FA) who developed acute lymphoblastic leukemia (ALL) (FAB-LI) followed by acute myeloid leukemia (AML) (FAB-M5) at relapse. The patient was diagnosed with early pre-B-cell ALL without preceding aplastic anemia and was treated with ALL-oriented chemotherapy which included doxorubicin (a total dose of 140 mg/m(2) administered), which is a topoisomerase II inhibitor. Complete remission was obtained, but after 38 weeks AML developed. The karyotype of ALL cells at diagnosis showed 46,XY, and that of AML cells at relapse was 46,XY, t(11;16)(q23;p13). An MLL gene rearrangement and MLL-CBP chimeric mRNA were found in AML, but not in ALL. A diagnosis of FA was confirmed by an increased number of chromosomal breaks and rearrangements in peripheral blood lymphocytes cultured with mitogen in the presence of mitomycin C. We conclude that this FA patient developed ALL followed by a therapy-related t(11;16)-AML resulting in an MLL-CBP fusion. Further examination of such patients would shed light on leukemogenesis in FA patients. Genes Chromosomes Cancer 27:264-269, 2000.

Amino Acid Sequence↗

PubMed2000

[A baby with shaken baby syndrome in whom early diagnosis resulted in good prognosis].

We encountered a 5-month-old baby with shaken baby syndrome, which had been caused by being thrown up about 50 cm in the air several times by his father. Intracranial hemorrhage, bleeding in the eye grounds in both eyes, and convulsion were noted on admission. Shaken baby syndrome was diagnosed from the history, and the patient was given necessary treatment, which led to favorable prognosis. Father was not aware of the danger of handling his baby in that way, and no sign of maltreatment was noted on the body surface of the baby. An attention should be payed that the danger leading into syndrome could be hidden among this kind of caring in the everyday life.

Cerebral Hemorrhage↗

PubMed1999

Defective control of apoptosis and mitotic spindle checkpoint in heterozygous carriers of ATM mutations.

Ataxia telangiectasia (AT) carrier-derived lymphoblastoid cell lines (AT-LCLs/hetero) with suboptimal ATM protein expression were examined for the regulation of radiosensitivity, apoptosis, and mitotic spindle checkpoint in response to DNA-damaging agents. Although AT-LCLs/hetero showed intermediate radiation sensitivity, as determined by clonogenic assay, they were resistant to early-onset apoptosis, as much as AT patient-derived LCLs (AT-LCLs/homo). Furthermore, two of three AT-LCLs/hetero showed defective mitotic spindle checkpoint control in response to X-ray irradiation, which is a recently characterized biological feature in AT-LCLs/homo. Our findings indicate that carriers of ATM mutation have biological abnormalities due to haploinsufficiency of ATM protein or dominant-negative effect of mutant ATM protein. Thus, although it is still controversial whether ATM mutation carriers are at higher risk for cancer during adulthood, our findings based on in vitro biological indicators support the notion that at least some of such carriers are at a higher risk for cancer development than those without ATM mutation. Our findings may help to reevaluate epidemiological studies on cancer susceptibility in AT carriers.

Apoptosis↗

PubMed1999

Secondary structure peptide mimetics: design, synthesis, and evaluation of beta-strand mimetic thrombin inhibitors.

Constrained dipeptide mimetic templates were designed to mimic the secondary structure of peptides in a beta-strand conformation. Two templates corresponding to the D-Phe-Pro portion of the thrombin inhibitor D-Phe-Pro-ArgCH2Cl were synthesized and converted into nine alpha-ketoamide and alpha-ketoheterocycle inhibitors of thrombin. Additionally, a template corresponding to L-Phe-Pro was synthesized and converted to a thrombin inhibitor. The in vitro inhibition of thrombin by these compounds was determined, and those corresponding to the D-Phe-Pro were found to be more potent inhibitors than the L-Phe-Pro mimetic. The alpha-ketoamides were found to be more potent than the alpha-ketoheterocycles but had much slower on rates. By comparison of a series of alpha-ketoamide analogues, it is apparent that the there is a preference for binding of bulky hydrophobic substituents in the P' portion of the thrombin active site. Three of the inhibitors (MOL098, MOL144, and MOL174) were screened against a series of coagulation and anticoagulation enzymes and found to be selective for inhibition of the coagulation enzymes. Two of the inhibitors were tested in in vitro models of intestinal absorption and found to have low absorption potential. The compounds were then tested in vivo in both rats and primates, and one of them (MOL144) was approximately 25% absorbed in both species. This study has delineated the synthesis of constrained dipeptide beta-strand mimetics and validated the potential for compounds of this type as potent thrombin inhibitors and possible drug leads.

Administration, Oral↗

PubMed1999

Identification of mutations in the c-mpl gene in congenital amegakaryocytic thrombocytopenia.

Congenital amegakaryocytic thrombocytopenia (CAMT) is a rare disorder expressed in infancy and characterized by isolated thrombocytopenia and megakaryocytopenia with no physical anomalies. Our previous hematological analysis indicated similarities between human CAMT and murine c-mpl (thrombopoietin receptor) deficiency. Because the c-mpl gene was considered as one of the candidate genes for this disorder, we analyzed the genomic sequence of the c-mpl gene of a 10-year-old Japanese girl with CAMT. We detected two heterozygous point mutations: a C-to-T transition at the cDNA nucleotide position 556 (Q186X) in exon 4 and a single nucleotide deletion of thymine at position 1,499 (1,499 delT) in exon 10. Both mutations were predicted to result in a prematurely terminated c-Mpl protein, which, if translated, lacks all intracellular domains essential for signal transduction. Each of the mutations was segregated from the patient's parents. Accordingly, the patient was a compound heterozygote for two mutations of the c-mpl gene, each derived from one of the parents. The present study suggests that at least a certain type of CAMT is caused by the c-mpl mutation, which disrupts the function of thrombopoietin receptor.

Child↗

PubMed1999

A case of fibrous histiocytoma of the liver.

Malignant fibrous histiocytoma (MFH) is a rare disease. We describe a 68-year-old man admitted to the hospital because of malaise. On admission, hematologic and serum chemical examinations showed no abnormalities. A tumor measuring 6.0 x 6.0 x 5.5 cm was found in segment S6 of the right lobe of the liver. A computed tomographic scan of the abdomen revealed a mass surrounded by a capsule-like region with a nonuniform shadow at its margin. The mass contained a nonuniform low density area. A magnetic resonance imaging scan showed low intensity on T1-weighted images and high intensity on T2-weighted images. An angiogram of the abdomen revealed a tumor with a darkly stained margin during the venous phase. Partial resection of the liver, including S6 and part of S7, was performed. On histopathological examination, this case was characterized by a storiform pattern. The inside of the tumor showed a storiform-pleomorphic pattern with inflammatory cell infiltration and partial mucinous degeneration. On immunohistochemical studies, the tumor cells stained positively for CD6. The diagnosis was MFH.

Aged↗

PubMed1999

Fusion of ETV6 to neurotrophin-3 receptor TRKC in acute myeloid leukemia with t(12;15)(p13;q25).

Chromosome translocations involving band 12p13 are known to be involved in a variety of hematologic malignancies, some of them resulting in rearrangement of the ETV6/TEL gene. Applying the fluorescence in situ hybridization (FISH) method, we found a cryptic translocation t(12;15)(p13;q25) in an adult acute myeloid leukemia (AML) patient. Hybridization with cosmid probes showed that the ETV6 gene was rearranged in this translocation. A patient-specific cDNA library was screened with ETV6 cDNA, and a novel fusion transcript was identified between the ETV6 and TRKC/NTRK3 gene located on 15q25. TRKC is a receptor tyrosine kinase that is activated by neurotrophin-3 (NT-3). It is known to be expressed broadly in neural tissues but not in hematologic cells, so far. ETV6-TRKC chimeric transcript encoded the pointed (PNT) domain of the ETV6 gene that fused to the protein-tyrosine kinase (PTK) domain of the TRKC gene. Two types of fusion transcript were determined, one that included the entire PTK domain of TRKC and the other in which the 3'-terminal 462 bp of TRKC was truncated within the PTK domain. Western blot analysis showed the expression of both chimeric proteins of 52 and 38 kD in size. Our results suggest that chimeric PTK expressed in the leukemic cells may contribute to cellular transformation by abnormally activating TRK signaling pathways. Moreover, this is the first report on truncated neurotrophin receptors associated in leukemia.

Acute Disease↗

PubMed1999

GM2 gangliosidosis AB variant: clinical and biochemical studies of a Japanese patient.

OBJECTIVE: To determine the clinical features and biochemical basis of the first Japanese patient with the GM2 gangliosidosis AB variant. METHODS: The clinical manifestations and laboratory findings in the patient were investigated. Cultured fibroblasts from the patient were analyzed by means of immunofluorescence staining with an anti-GM2 ganglioside monoclonal antibody and thin-layer chromatography and immunostaining. GM1 ganglioside catabolism in cultured cells was analyzed by pulse labeling, and the amount of GM2 activator in cells was determined by Western blot analysis. Gene analysis was performed according to standard protocols. RESULTS: The patient showed progressive neurologic manifestations of quite early onset. Muscular weakness and hypotonia became evident by 1 month of age, and the patient then developed a startle reaction, severe psychomotor retardation, and myoclonic seizures. Immunocytochemical analysis clearly revealed the accumulation of GM2 ganglioside in cultured fibroblasts from the patient, and thin-layer chromatography confirmed it. Western blot and metabolic studies showed a complete deficiency of GM2 activator. Gene analysis did not reveal any mutations in the protein coding region of the GM2 activator gene. CONCLUSION: The clinical features and biochemical basis of this Japanese patient with GM2 gangliosidosis AB variant were determined. Immunocytochemical analysis using cultured fibroblasts as samples is available for the diagnosis of this disease.

Anticonvulsants↗

PubMed1999

Limitations of spontaneous reperfusion and conventional medical therapy to afford myocardial protection through antecedent angina pectoris in acute myocardial infarction.

Despite the cardioprotective effect of rapid coronary reperfusion, the effects of spontaneous recanalization on myocardial viability and metabolism are unknown. We studied whether preinfarction angina affords cardioprotection when spontaneous coronary reperfusion occurred in acute infarct patients. Myocardial tomographies with thallium and I-123-labeled-beta-methyl-p-iodophenyl penta-decanoic acid (BMIPP) were performed in 27 acute myocardial infarct patients treated medically: 15 patients had preexisting angina before infarction (group A) and 12 did not (group B). Thallium and BMIPP abnormalities and regional function were quantified by a polar map and contrast ventriculography, respectively. There was no significant difference between thallium and BMIPP in the severity index in groups A and B (89 +/- 97 vs. 85 +/- 68, 97 +/- 28 vs. 95 +/- 27, respectively), and no significant difference between the groups in the thallium or BMIPP severity index. The ratio of the thallium severity index to that of BMIPP and the regional wall-motion abnormality index were identical in groups A and B. Both patient groups were divided into 2 subgroups based on the presence or absence of spontaneous coronary reperfusion: subgroups A1 and A2, and subgroups B1 and B2, respectively. There were no significant differences among the 4 subgroups in severity indexes for both tracers, the thallium/BMIPP ratio, or the asynergy score. The BMIPP severity index correlated significantly with that of thallium in all subgroups, but no significant difference between the regression lines was found. It is therefore unlikely that spontaneous coronary recanalization affords beneficial effects through preservation of myocardial viability in an ischemia-related zone, suggesting that the cardioprotective effect of preinfarction angina is a limited phenomenon in patients undergoing rapid coronary reperfusion.

Adult↗

PubMed1999

Cystic lymphangiomas of the colon.

We report a patient with cystic lymphangiomas diagnosed by endoscopic ultrasonography and resected by partial polypectomy. A 42-year-old woman consulted a nearby physician because of a positive fecal occult blood test. Barium enema and colonoscopy revealed the presence of abnormalities. On March 11, 1997, she was admitted to our department for further evaluation and treatment. A barium enema examination revealed two protruding lesions in the transverse colon. Colonoscopy showed a teardrop-type mass in the left side of the transverse colon. The mass was cushion-sign positive, and its shape readily changed on respiration and with changes in body position. Another superficial smooth mass was found in the right side of the transverse colon. Ultrasonography of the colon confirmed the presence of a submucosal mass showing a cyst-like pattern. Cystic lymphangiomas were diagnosed and resected endoscopically. Histopathological examination revealed markedly dilated ducts consisting of a single layer of endothelial cells in the submucosa of the colon. The diagnosis was cystic lymphangioma.

Adult↗

PubMed1999

Unique radiological appearance of a microcystic meningioma.

A 35-year-old female presented with partial complex seizures. Computed tomography (CT) showed a slightly high density mass over the right frontal convexity, with heterogeneous contrast enhancement. T1-weighted magnetic resonance (MR) imaging showed the tumour as a hypo-intense lesion, with faint reticular enhancement after intravenous injection of gadolinium-diethylenetriaminepenta-acetic acid. The tumour was totally removed. The specimen was extremely soft and moist. The histological diagnosis was microcystic meningioma. The tumour cells were composed of typical meningothelial cells and stellate cells. The degenerative character of the tumour may be reflected in the poor enhancement on CT and MR imaging. This faint enhancement effect may be a neuro-imaging characteristic indication of this rare microcystic variant of meningioma.

Adult↗

PubMed1999

Low-dose cyclosporin for multiple colonic ulcers associated with mixed connective tissue disease.

This report describes a patient with multiple colonic ulcers and mixed connective tissue disease. The histological findings of the colonic lesions showed vasculitis with T-cell infiltration, and the peripheral T cells were frequently in the activated phase of the cell cycle. In this patient, low-dose cyclosporin treatment (2.5 mg/kg/day) inhibited the T-cell activation in the peripheral lymphocytes and was very effective in the gastrointestinal disorder, which might be related to T-cell activation. This case suggests the possibility that even low-dose cyclosporin can exert a great influence on peripheral T cells and directly inhibit T-cell activation, thereby improving symptoms related to T-cell activation.

Adult↗

PubMed1999

Interphase fluorescence in situ hybridization overcomes pitfalls of G-banding analysis with special reference to underestimation of chromosomal aberration rates.

Fluorescence in situ hybridization (FISH) is suitable for detecting different types of chromosome aberrations on interphase nuclei even in specimens with no or few chromosome metaphases. However, it is not known why FISH is superior to conventional G-banding analysis. The sensitivity of interphase FISH was compared to that of G-banding analysis in 288 leukemia/lymphoma patients for 10 different types of chromosome aberrations: t(9;22) (M- and m-BCR), t(8;21), 11q23 abnormalities, t(15;17), del(5)/-5, del(13)/-13, +8, -7, and +12. The results revealed that t(15;17) positive cells could not proliferate well in culture, leading to underestimation of abnormality by G-banding. Monosomy 7 in acute myelocytic leukemia (AML) and myelodysplastic syndrome (MDS) as well as trisomy 12 and deletion chromosome 13 in chronic lymphocytic leukemias (CLL) were also severely underestimated by G-banding. On the other hand, no discrepancies were observed in t(8;21), t(9;22), translations involving 11q23, or in trisomy 8. These findings indicate the superiority of interphase FISH over conventional cytogenetics for detecting chromosome abnormalities in small clones, especially for monosomy 7 or (15;17) translocations.

Chromosome Aberrations↗

PubMed1999

Cloning of soluble alkaline phosphatase cDNA and molecular basis of the polymorphic nature in alkaline phosphatase isozymes of Bombyx mori midgut.

A cDNA coding for soluble type alkaline phosphatase (sALP) of Bombyx mori was isolated. Deduced amino acid sequence showed high identities to various ALPs and partial similarities to ATPase of Manduca sexta. Using this cDNA sequence as a probe, the molecular basis of electrophoretic polymorphism in sALP and membrane-bound type ALP (mALP) was studied. As for mALP, the result suggested that post-translational modification was important for the proteins to express activity and to represent their extensive polymorphic nature, whereas the magnitude of activities was mainly regulated by transcription. On the other hand, sALP zymogram showed poor polymorphism, but one exception was the null mutant, in which the sALP gene was largely lost. Interestingly, the sALP gene was shown to be transcribed into two mRNAs of different sizes, 2.0 and 2.4 Kb. In addition to the null mutant of sALP, we found a null mutant for mALP. Both of these mutants seem phenotypically silent, suggesting that the functional differentiation between these isozymes is not perfect, so that they can still work mutually and complement each other as an indispensable enzyme for B. mori.

Alkaline Phosphatase↗

PubMed1999

Cardiac BMIPP imaging in acute myocardial infarction.

Fatty acid metabolism functions as a major energy-producing system under aerobic conditions, but it is impaired immediately after myocardial ischaemia. This imaging can provide intracellular information which cannot be obtained by angiographical, perfusional or functional analysis. 123I-BMIPP and perfusion imagings in patients with acute myocardial infarction have demonstrated three different correlations between myocardial perfusion and fatty acid metabolism: concordant defects of perfusion and BMIPP which represent scar or non-viable tissue; lower BMIPP uptake relative to perfusion (perfusion-BMIPP mismatch) which implicates metabolically damaged, often dysynergic, but viable myocardium; and equivalently normal uptakes of perfusion and BMIPP in completely salvaged myocardium. Identification of these perfusion-metabolism correlations contributes to the detection of ischaemia-related myocardial injury in viable and non-viable myocardium, to the prediction of post-ischaemic or post-interventional functional recovery and to the identification of patients who have myocardium at ischaemic risk. Further clinical investigations might reveal more clearly the pathophysiological and prognostic implications of cardiac BMIPP imaging in patients with acute myocardial infarction.

Fatty Acids↗

PubMed1999

Sphingomonads from marine environments.

Sphingomonas species play an important role in the ecology of a range of marine habitats. Isolates and 16S-rRNA clones have been obtained from corals, natural and artificial sources of marine hydrocarbons and eutrophic and oligotrophic waters, and have been isolated as hosts for marine phages. In addition they are found in oceans spanning temperature ranges from polar to temperate waters. While less is known about marine sphingomonads in comparison to their terrestrial counterparts, their importance in microbial ecology is evident. This is illustrated by, for example, the numerical dominance of strain RB2256 in oligotrophic waters. Furthermore, the known marine sphingomonads represent a phylogenetic cross-section of the Sphingomonas genus. This review focuses on our present knowledge of cultured isolates and 16S-rDNA clones from marine environments.

Journal Article↗

PubMed1999

Frequent allelic loss of the RB, D13S319 and D13S25 locus in myeloid malignancies with deletion/translocation at 13q14 of chromosome 13, but not in lymphoid malignancies.

In order to identify a commonly deleted region of 13q14 on chromosome 13, we performed fluorescence in situ hybridization (FISH) on 17 patients with myeloid malignancies and 12 patients with lymphoid leukemia/lymphoma who exhibited either deletion or translocation at 13q14. Three cosmid probes (RB, D13S319 and D13S25) hybridizing to sequences on 13q14 were used. Fourteen of the 17 patients with myeloid malignancies (82.4%) exhibited allelic loss at the RB, D13S319 and D13S25 locus, whereas only three of the 12 patients with lymphoid malignancies (25.0%) exhibited loss within these loci. These three patients had chronic lymphocytic leukemia (CLL). Six, two and one of the remaining nine lymphoid leukemia/lymphoma patients had breakpoints centromeric to the RB gene, telomeric to D13S25 and within the D13S319 locus, respectively. A high frequency of allelic loss was found using these probes in patients with myeloid malignancies, compared to in patients with leukemia in the lymphoid origin, except CLL patients. These results indicate that loss of the RB gene itself or a region between RB and D13S319, which includes commonly deleted loci, may play an important role in myeloid leukemogenesis.

Adult↗