PubMed Health⌕ Search

Biomedical subjects

A Okano

Publications and source records attributed to A Okano.

At least 37 records · Page 2Linked to original sources

Effectiveness of an antiplatelet agent for coronary artery ectasia associated with silent myocardial ischemia.

A 74-year-old Japanese male was referred to our hospital because of an abnormal electrocardiogram. The electrocardiogram revealed tall P waves in leads II, III, and aV(F). Echocardiography disclosed hypokinesis extending from the anteroseptal region to the apex. Iodine-123 15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (123-BMIPP) scintigraphy revealed reduced uptake from the anteroseptal region to the apex. Coronary arteriography demonstrated diffuse dilatation of the right and left coronary arteries without organic stenosis, and left ventriculography showed hypokinesis at the same area. Furthermore, the coronary flow reserve in the left anterior descending artery was decreased. He was treated with an antiplatelet agent. Ten months later, the left ventriculography, 123I-BMIPP scintigraphy findings and coronary flow reserve were normalized. These findings demonstrate that antiplatelet therapy may be useful in the preservation of left ventricular function in patients with coronary artery ectasia.

Aged↗

Pseudotumorous pancreatitis associated with ulcerative colitis.

Pancreatitis is believed to be one of the uncommon extraintestinal manifestations of ulcerative colitis (UC). A 66-year-old woman who had been treated for UC for eight months was admitted to our hospital because of epigastralgia. Laboratory examinations revealed elevated pancreatic enzymes. Because differentiation of pseudotumorous pancreatitis from pancreatic cancer was difficult by the imaging findings, she underwent a distal pancreatectomy. Histologically, the tumorous lesion was composed of fibrosis with lymphocytic infiltration. We concluded that this case was pseudotumorous pancreatitis as an extraintestinal manifestation of UC.

Aged↗

Clinical characteristics of B-cell lymphoma-associated hemophagocytic syndrome (B-LAHS): comparison of CD5+ with CD5- B-LAHS.

OBJECTIVE: B-cell lymphoma-associated hemophagocytic syndrome (B-LAHS) has been increasingly reported in Asia and is regarded as a variant of intravascular lymphomatosis (IVL). Recently CD5 was reported to be expressed in some cases of diffuse large cell lymphoma and IVL. We therefore examined the expression of CD5 on lymphoma cells in B-LAHS and compared the clinical and laboratory data between CD5+ and CD5- B-LAHS. METHODS: The expression of CD5 on lymphoma cells was examined using flow cytometry and immunohistochemical analysis of paraffin sections. The clinical records were reviewed to characterize clinical features. PATIENTS: Twelve patients with B-LAHS; ten men and two women, age ranging from 41 to 82 years (median, 63.5 years) were included in this study. RESULTS: B-LAHS is characterized by fever and hepatosplenomegaly without lymphadenopathy at the initial presentation. Histological examination showed hemophagocytosis and infiltration of lymphoma cells in the bone marrow, and in some cases intravascular proliferation of lymphoid cells characteristic of IVL. All patients showed increased levels of lactate dehydrogenase, C-reactive protein, ferritin and soluble interleukin-2 receptor. In eight of the twelve patients, lymphoma cells were positive for CD5. But no differences were observed in the clinical or laboratory findings between CD5+ B-LAHS and CD5- B-LAHS. CONCLUSION: No clinical differences were observed between CD5+ B-LAHS and CD5- B-LAHS. Further studies are required to elucidate the differences in pathogenesis between these two subgroups of B-LAHS.

Adult↗

Early relapse after high-dose chemotherapy rescued by tumor-free autologous peripheral blood stem cells in acute lymphoblastic leukemia: importance of monitoring for WT1-mRNA quantitatively.

A 24-year-old woman who suffered from ALL with MLL gene rearrangement received high-dose chemotherapy followed by autologous PBSC transplantation during complete remission (CR). Reverse transcriptase-polymerase chain reaction (RT-PCR) used to detect MLL/LTG4 chimeric mRNA showed no minimal residual disease (MRD) in the graft or bone marrow at the transplantation. However, the leukemia relapsed four months after transplantation. Retrospective analysis of quantitative measurement of Wilms tumor gene (WT-1) mRNA showed an increased level in the bone marrow although it was within the normal range. These observations suggest that careful monitoring of MRD by quantitative measurement of WT-1 mRNA in addition to disease-specific chimeric mRNA is required to predict relapse.

Adult↗

[Philadelphia chromosome-positive acute lymphoblastic leukemia with monosomy 7 successfully treated with intermediate- and high-dose ara-C].

A 52-year-old man was admitted for treatment of acute lymphoblastic leukemia (ALL). The bone marrow was hypercellular with 67.2% blasts, which were negative for peroxidase, and expressed CD13, CD33, CD34, CD10 and CD7. Cytogenetic and molecular studies revealed t(9;22) and -7(Ph/-7) with major BCR/ABL rearrangement. The patient was treated with the L-AdVP regimen, but failed to achieve complete remission (CR). He then received two courses of chemotherapy consisting of intermediate- and high-dose cytarabine (ara-C), resulting in CR. This case suggests that Ph/-7 ALL with major BCR/ABL gene rearrangement showing coexpression of myeloid antigens may be sensitive to intermediate- and high-dose ara-C.

Antimetabolites, Antineoplastic↗

[Therapy-related myeloid leukemia following platinum-based chemotherapy for ovarian cancer].

A 40-year-old woman, who had suffered from AML (M1) in 1983, developed ovarian cancer (stage IIIc) in December 1996 after long-term remission. She underwent surgical resection of the cancer, 10 courses of standard chemotherapy and tandem PBSCT (total dose: CBDCA 6,750 mg, CDDP 200 mg, CPA 16,000 mg, THP-ADR 450 mg). After receiving the last course of chemotherapy in June 1998, she was referred to our hospital in September 1998 because of pancytopenia. Laboratory findings showed pancytopenia with 34% leukemic cells, which were positive for alpha NBE and negative for POX and CAE. Surface-marker analysis of the leukemic cells showed positivity for CD11c, CD33, CD56, and DR, and chromosome analysis revealed 47, XX, +8. The patient was diagnosed as having AML (M5a), and received induction therapy consisting of IDR and Ara-C, which led to complete remission. As she had not received etoposide, this case was thought to have been therapy-related leukemia due to the platinum agents used for treating the ovarian cancer.

Adult↗

Effect of oxidative stress on development and DNA damage in in-vitro cultured bovine embryos by comet assay.

The correlation of oxidative stress on development and DNA damage in bovine embryos was investigated by the comet assay (single-cell microgel electrophoresis), an effective technique for detecting single-strand DNA breakage. After in vitro maturation and fertilization, one-cell stage embryos without cumulus cells were cultured for 8 days in SOF medium containing amino acids plus 5% FCS under low (5%) and atmospheric (20% ) oxygen concentration. After 8 days of culture, the extent of blastocyst formation was significantly decreased (P<0.001) when embryos were cultured under 20% oxygen concentration (5.8 +/- 2.4%) when compared to embryos cultured under 5% oxygen concentration (35.1 +/- 6.7%). At the day 3 of development, DNA damage of individual embryos cultured under 5% or 20% oxygen concentration was measured by the comet assay, which entails microgel electrophoresis that can readily detect damaged DNA. After measuring the DNA damage in individual embryos by the comet assay, the length (149.9 +/- 15.3 microm) of the migrating DNA fragment that is indicative of damaged DNA was significantly increased (P<0.001) in the embryos cultured under 20% oxygen concentration when compared to embryos cultured in 5% oxygen concentration (42.3 +/- 7 microm). The length of damaged DNA in more than 50% of embryos was less than 50 microm. when embryos were cultured under 5% oxygen concentration. In contrast, the distribution of damaged DNA shifted to the more damaged extent when embryos were cultured under 20% oxygen concentration. These results demonstrate that the retardation in bovine embryo development than in likely due oxidative stress as a consequence of the higher atmospheric oxygen concentration is positively correlated with an increase in the extent of DNA damage. Moreover, these results demonstrate that the comet assay is a useful method to evaluate embryo culture conditions.

Animals↗

Occurrence of a transcription factor, signal transducer and activators of transcription 3 (Stat3), in the postsynaptic density of the rat brain.

Distribution of a signal transducer and activators of transcription 3 (Stat3) was examined in the rat brain. Immunoreactivity was distributed in the neurons, as well as glia cells, throughout the rat brain. Western blotting of subcellular fractions showed distribution in the synaptic fractions (synaptosome, synaptic plasma membrane, and postsynaptic density, PSD). The occurrence of Stat3 in the synaptic site, especially in the PSD, was confirmed by immunoelectron microscopic examination. The PSD fraction had an activity that phosphorylated Stat3 at the tyrosine-705 site, which was confirmed by both Western blotting and immunoprecipitation. The PSD fraction also had a janus kinase 2 (Jak2)-like molecule, Jak2, believed to phosphorylate Stat3. These results indicate that the Jak2/Stat3 signaling system, a major pathway of cytokine signaling in the immune response system, may also play a role at the postsynaptic sites.

Animals↗

Tumor necrosis factor-alpha and its receptor in the corpus luteum of pregnant cows.

The objective of this study was to investigate the presence of tumor necrosis factor (TNF)-alpha mRNA and TNF-alpha receptors in the bovine corpus luteum (CL) during the gestation period. TNF-alpha mRNA and TNF-alpha receptors were determined on bovine CL from pregnant cows at three stages: trimester I (fetal crown-rump length; 6-20 cm), trimester II (25-45 cm) and trimester III (50-80 cm). TNF-alpha mRNA was detected by an RT-PCR analysis in the CL of all stages of gestation. A Scatchard analysis revealed the presence of a high-affinity binding site (Kd; 5.1-6.9 nM) in the CL membranes collected at each stage of gestation. Furthermore, the concentrations of TNF-alpha receptors in the CL of trimesters I (24. 0 +/- 1.95 pmol/mg protein) and III (21.6 +/- 2.39 pmol/mg protein) of gestation were significantly higher than the concentration in trimester II (14.9 +/- 2.07 pmol/mg protein) (P < 0.05). These results indicate that TNF-alpha is locally produced and that TNF-alpha receptors are present in bovine CL during the gestation period, and suggest that TNF-alpha plays one or more roles as a paracrine factor in regulating bovine CL function during the entire gestation period.

Animals↗

Alcohol sclerotherapy of hepatic cysts: its effect in relation to ethanol concentration.

While ultrasonically guided percutaneous aspiration and ethanol injection therapy has proved useful for non-neoplastic giant hepatic cysts that cause symptoms, the optimum quantity of ethanol injected into hepatic cysts has not been established. In eight patients with non-neoplastic giant hepatic cysts who were treated by ethanol injection, ethanol concentration in cystic fluid after treatment was estimated. Ethanol concentrations ranged from 5.9 to 47.6%. Hepatic cyst regressed almost completely in five cases; in all of which, the estimated ethanol concentrations were more than 40%. Our results suggest that it is desirable to drain cystic fluid as much as possible and to inject ethanol as little as possible, so that the estimated ethanol concentration in the cyst exceeds 40% for maximal effect and minimal side effects.

Journal Article↗

Expression of T-cell-associated antigens in B-cell non-Hodgkin's lymphoma.

We performed the immunophenotyping of 101 patients with B-cell non-Hodgkin's lymphoma (B-NHL) using two-colour flow cytometry (FCM) and found that lymphoma cells coexpressed at least one kind of T-cell-associated antigen (T-Ag; CD2, CD5, CD7) in 25 patients (24. 8%). Among these three T-Ags, CD5 was the most frequently expressed, in 21 patients (20.8%), followed by CD7, expressed in five patients (5.0%), and CD2, which was expressed in two patients (2.0%). Two kinds of T-Ag were simultaneusly expressed in three patients (CD2/CD5, CD2/CD7, and CD5/CD7, each expressed in one patient). Concerning the expression pattern of T-Ag, there were no significant differences between lymph nodes and extranodal organs in the three patients with T-Ag-positive B-NHL (T-Ag(+) B-NHL) who were analysed. When comparing the clinical features between T-Ag(+) B-NHL and T-Ag-negative B-NHL (T-Ag(-) B-NHL), extranodal involvement and higher International Prognostic Index (H and H.I.) were significantly frequent in the former subgroup (P = 0.0119 and P = 0. 0302 respectively).

Adolescent↗

[Autologous transplantation of Ph-negative peripheral blood stem cells for treatment of chronic myelogenous leukemia].

A 21-year-old man, diagnosed in March 1997 as having chronic myelogenous leukemia (CML), received hydroxyurea followed by daily interferon (IFN) until December 1998, when the additional chromosome abnormality of +8 appeared. As no suitable matched donor was available, the patient received mobilization therapy consisting of mini-ICE (idarubicin, cytarabine, etoposide) followed by G-CSF subcutaneously. During hematopoietic recovery, a total of 12 x 10(6)/kg CD34-positive cells were harvested. Cytogenetic analysis of peripheral blood stem cell (PBSC) products using FISH revealed 1% BCR/ABL fusion signals. In March 1999, he received conditioning therapy consisting of busulfan (16 mg/kg) and cyclophosphamide (120 mg/kg) followed by infusion of 5 x 10(6)/kg CD34-positive cells. A neutrophil count of 500/microliter and a platelet count of 5 x 10(4)/microliter were attained by days 20 and 38, respectively. Bone marrow aspirates showed 2.6% BCR/ABL fusion signals on day 35 after autologous PBSC transplantation, and the patient remained in chronic phase until the sixth month, when a cytogenetic relapse (Ph, +8:4/20) occurred. These observations suggest that Ph-negative progenitor cells can be harvested using a mini-ICE regimen followed by G-CSF, and that autologous PBSC transplantation is feasible in patients with CML resistant to IFN.

Adult↗

Identification of mRNAs localizing in the postsynaptic region.

Local protein synthesis using mRNAs readily distributed in the dendrites is believed to play an important role in maintaining the already expressed synaptic plasticity. To find proteins translated in the postsynaptic region, such as neuronal dendrites, we tried to identify the mRNAs associated with the postsynaptic density (PSD) fraction prepared from a rat's forebrain. The PSD-associated mRNAs were amplified by reverse transcriptase-based polymerase chain reaction (RT-PCR), separated by polyacrylamide gel electrophoresis, and sequenced. The database search revealed, among 130 mRNAs sequenced, 17 known and 108 unknown sequences, while five mRNAs were too short for the search. Of the mRNAs with unknown sequences, we selected 33 genes with a length longer than 150 bases, performed in situ hybridization, and found that at least 12 mRNA types were localized in the dendrites. These results suggest that a large number of mRNAs localize around the postsynaptic area of the neuronal cells in the central nervous system. In addition, our method proved efficient in identifying collectively the mRNAs localizing in the dendrites.

Animals↗

Assessment of DNA damage in individual hamster embryos by comet assay.

DNA damage induced by either light exposure or oxidative stress likely contributes to the compromised development in vitro of cultured preimplantation embryos. Using the comet assay, which entails microgel electrophoresis that can readily detect single-strand breaks in DNA, a significant increase in DNA damage was detected in individual one-cell hamster embryos that were treated with either ultraviolet light or hydrogen peroxide. In addition, an increase in DNA damage also was observed following exposure of one-cell embryos to visible light. When the embryos were placed in drops of culture medium that were covered with mineral oil and the dishes then placed in a portable incubator containing 5% CO(2) in air at 37 degrees C, visible and UV light irradiation for 30 min still induced extensive DNA damage when compared to control embryos that were kept in the dark. In contrast, infrared irradiation did not induce an increase in DNA damage. DNA damage also was measured in individual one- and two-cell stage embryos developed in vivo or in vitro. The extent of DNA damage in the cultured embryos was significantly greater than in embryos that developed in vivo. These results highlight the usefulness of the comet assay to assess DNA damage in individual preimplantation embryos and how the assay can be used to monitor culture conditions in vitro.

Animals↗

Evaluation of antivascular and antimitotic effects of tubulin binding agents in solid tumor therapy.

Tubulin binding agents (TBAs) reduce tumor perfusion and inhibit mitosis of tumor cells in solid tumors, but it is not clear which effects contribute to the suppression of solid tumor growth. We evaluated the antivascular and antimitotic effects of several TBAs, combretastatin A-4 (CS A-4) phosphate, AC-7700, a novel CS A-4 derivative, colchicine, E7010, and vinblastine, on subcutaneous (s.c.) murine colon26 adenocarcinoma (c26). Tolerable doses of vinblastine and E7010) strongly inhibited tumor growth and induced mitotic arrest of tumor cells without affecting tumor perfusion. Colchicine had no effect on tumor growth and perfusion. When the injected dose was increased to the lethal range, however, these drugs markedly reduced tumor perfusion and caused necrosis of tumor tissue. Within the tolerable dose range, AC-7700 both strongly suppressed tumor growth and reduced tumor perfusion, and CS A-4 phosphate also exhibited a moderate antivascular effect. To evaluate the contribution of antivascular activity of TBAs to tumor growth suppression, excluding their direct cytotoxic effect on tumor cells, we established c26/acr, which is resistant to TBAs in vitro. Although E7010 showed a reduced suppressive effect on s.c. c26/acr tumor growth as compared with its effect on wild-type c26, AC-7700 remained potent against both cell lines. These results indicate that TBAs exert antivascular and antimitotic effects on solid tumors with marked differently effective dose ranges from agent to agent, and that the antivascular effect of TBAs inhibits solid tumor growth independently of the direct cytotoxic effect on tumor cells.

Adenocarcinoma↗