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M Oyama

Publications and source records attributed to M Oyama.

At least 19 recordsLinked to original sources
PubMed2005

Isolation and expression of FIP-2 in wounded pulp of the rat.

Pulpal wound healing followed by cavity preparation may involve reactionary or reparative dentinogenesis in relation to the cavity position; however, little is known about the molecular responses. We aimed to isolate and analyze genes induced or suppressed in the wounded pulp to identify molecular processes involved in the pulp responses to injury. Twenty-three cDNAs were isolated by cDNA subtraction between healthy and wounded pulp of rats. By library screening, we identified rat 14.7K-interacting protein (rFIP)-2A and B genes homologous to human FIP-2, being involved in regulating membrane trafficking and cellular morphogenesis. RT-PCR analysis showed induction for only rFIP-2B in the wounded pulp. In situ hybridization analysis revealed that both rFIP-2s were expressed strongly in condensing mesenchymal cells of the palatal process and surrounding Meckel's cartilage, but not in intramembranous chondrogenic cells. Thus, up-regulated rFIP-2B expression may play a role in regulating membrane trafficking or cellular morphogenesis of these embryonic and wounded pulpal cells.

Amino Acid Sequence↗
PubMed2003

Lymphoid blast crisis of chronic myelogenous leukemia occurring more than 11 years after receiving an allogeneic bone marrow transplant for chronic myelogenous leukemia in myeloid blast crisis at onset.

A 25-year-old male developed lymphoid blast crisis (BC) of chronic myelogenous leukemia (CML) more than 11 years after receiving an allogeneic bone marrow transplant (alloBMT) for CML with myeloid BC at presentation from his HLA-identical brother. The lymphoid BC of CML probably occurred without a preceding chronic phase of CML. This case illustrates the difficulties involved in determining the appropriate length of follow-up after alloBMT.

Adult↗
PubMed2001

Graft failure due to hemophagocytic syndrome after autologous peripheral blood stem cell transplantation.

Hemophagocytic syndrome (HPS) after hematopoietic stem cell transplantation can occasionally cause graft failure. We describe a female patient with B-cell non-Hodgkin's lymphoma (NHL) with graft failure due to HPS 12 days after autologous peripheral blood stem cell transplantation (PBSCT). Autologous PBSCT was carried out during unconfirmed/uncertain complete remission according to the Cotswolds classification after 6 cycles of biweekly (cyclophosphamide, doxorubicin, vincristine, and prednisolone) therapy and 3 courses of salvage chemotherapy including etoposide. The patient developed a high fever on day 2 post-PBSCT. Her white blood cell count rose to 0.9 x 10(9)/L on day 10 post-PBSCT, but then began to decrease. A bone marrow aspirate on day 12 post-PBSCT revealed an increase in the number of benign histiocytes with hemophagocytosis, and the patient was diagnosed with HPS. Although high-dose methylprednisolone therapy was continued, her white blood cell count further decreased to 0.3 x 10(9)/L, and the patient died of multiple organ failure on day 29 post-PBSCT. A computed tomography scan did not identify recurrent NHL, and necropsy specimens from the bone marrow, liver, and kidney revealed no neoplastic infiltration. Bone marrow necropsy showed marked hypocellularity with active histiocytic hemophagocytosis. HPS may have been induced by infection with methicillin-resistant Staphylococcus aureus rather than by lymphoma-associated HPS.

Aged↗
PubMed2001

A variant form of acute promyelocytic leukemia with marked myelofibrosis.

We describe a variant form, French-American-British (FAB) M3v, of acute promyelocytic leukemia (APL; FAB M3) with atypical morphocytochemical features, immature antigens (CD34 and HLA-DR) and marked myelofibrosis (MF). Usual APL cells do not express CD34 or HLA-DR antigens. MF may be more frequently observed in patients with M3v expressing CD34 and HLA-DR antigens than in patients with M3 lacking these antigens. Despite marked MF, recovery from the hypoplastic phase in the case we described was not delayed after remission induction chemotherapy consisting of enocitabine, 200 mg/mi2 intravenously; 6-mercaptopurine, 70 mg/m2 orally for 10 days; daunorubicin 40 mg/m2 intravenously for 4 days; and all-trans retinoic acid 45 mg/M2 orally between days 20 and 33. The promyelocytic leukemia-retinoic-acid receptor (PML-RAR) alpha fusion transcript, according to reverse transcriptase-polymerase chain reaction (RT-PCR), became negative in the bone marrow after the first course of consolidation chemotherapy. Autologous peripheral blood stem cell transplantation (autoPBSCT) was carried out after 3 courses of consolidation chemotherapy. There were no specific complications based on MF throughout the clinical course, including engraftment in autoPBSCT. The patient has been without MF and in molecular remission, defined as disappearance of the PML-RAR alpha fusion transcript according to RT-PCR, for 21 months. Longer follow-up will clarify the effects of autoPBSCT on prognosis in APL with MF.

Adolescent↗
PubMed2001

Systemic effects of transdermal testosterone for the treatment of microphallus in children.

OBJECTIVES: To elucidate the metabolic effects of topical testosterone for the treatment of microphallus in children. METHODS: We administered 5% testosterone ointment to 50 prepubertal boys for the treatment of microphallus, allowing us to observe its metabolic effect on plasma concentrations of testosterone as a marker of transdermally absorbed testosterone, insulin-like growth factor (IGF)-I as a marker of growth hormone secretion status, and osteocalcin as a marker of bone metabolic turnover. RESULTS: Transdermal application of testosterone for 30 days at a dose that affects penile growth increased mean (+/-SD) plasma testosterone concentrations from 7.5+/-5.1 to 31.0+/-8.2 ng/dL (pre- vs. post-treatment, respectively; P<0.01). This was associated with a slight but statistically significant elevation of IGF-I concentrations (117.2+/-76.9 vs. 154.4+/-81.5 ng/mL; P<0.05). No significant change in osteocalcin levels was found. CONCLUSIONS: When using testosterone ointment as a treatment for microphallus, it should be borne in mind that this application has systemic effects.

Administration, Cutaneous↗
PubMed2001

Neurogenic thoracic outlet syndrome in whiplash injury.

A prospective study of 110 patients was carried out to determine the pathogenic significance of trauma to the upper body in the development of neural compressive irritation at the thoracic outlet. Twenty-nine patients were reviewed as cervical strain injuries (N group), 25 patients as probable neurogenic thoracic outlet syndrome (NTOS) (PT group), 39 patients as definite NTOS (T group), and 17 patients as NTOS associated with cervical disc disease (CD-T group). The time lapse between accident and diagnosis and the duration of treatment were significantly longer in T patients or CD-T patients than those in the N group. Radiography of NTOS patients also showed a higher percentage of cervical spine-length/height ratio. Traumatic NTOS would suggest two types related to direct damage of scalene muscles that included some physical aspects of cervical disc disease. Pathogenesis provided a key to the resolution of more complex posttraumatic problems of whiplash injury.

Adolescent↗
PubMed2001

Iron-Mediated regulation of alkaline proteinase production in Pseudomonas aeruginosa.

We analyzed the regulation by iron of alkaline proteinase (AP) production in Pseudomonas aeruginosa. Extracellular AP production was detected from the mid-logarithmic to the stationary phase by an antibody-based assay system, and was strongly repressed by iron in the medium. This repression was shown by Northern hybridization and primer extension to occur at the level of transcription. The primer extension analysis revealed that the start point of transcription of AP gene was the nucleotide position -84 from the start point of translation. Furthermore, we investigated whether this transcriptional repression involved PvdS protein. Using the mutant strain of pvdS, the alternative sigma factor gene revealed that the PvdS protein is required for the full expression of AP, and a previous study showed that expression of pvdS is also repressed by iron. Therefore, we thought that one mechanism of repression of AP production operated through reduction of the PvdS protein level. Purified AP decomposed the transferrin, and released iron from it. Purified AP added to the medium containing transferrin as the only iron source enhanced the growth of P. aeruginosa. Moreover, mutation in the AP gene decreased the growth rate in the medium containing the transferrin as the only iron source. These results clearly indicated that AP expression should occur in a free-iron-deficient environment and emphasized the importance of AP to iron acquisition in the infection site.

Apoproteins↗
PubMed2001

Treatment of human renal cell carcinoma by a conditionally replicating herpes vector G207.

PURPOSE: Surgical removal remains the only potentially curative therapy for renal cell carcinoma. In this study we evaluated the inhibitory effect of the replication competent engineered herpes simplex virus type 1, G207, for renal cell carcinoma in vitro and in vivo. MATERIALS AND METHODS: The nature of G207 enables it to replicate within cancer cells, thus, causing cytolysis, but replication is restricted within normal cells. The susceptibility of the human renal cancer cell lines ACHN and A498 to G207 at a multiplicity of infection of 0.1 was examined. In addition, the growth characteristics of G207 was assessed. In vivo athymic mice bearing subcutaneous tumors were inoculated with 1 x 10(7) plaque forming units of G207 intra-neoplastically. For pathological analysis subcutaneous tumors were stained with X-gal. RESULTS: Two cell lines were efficiently destroyed by G207 within 1 week. The viral yields of G207 increased in a time dependent manner. In vivo the intra-neoplastic inoculation of G207 caused significantly decreased tumor growth in athymic mice harboring subcutaneous human renal cancer cells. On day 14 the mean growth ratio of ACHN and A498 lesions was significantly inhibited in G207 treated compared to control tumors (p <0.005 and <0.0001, respectively). CONCLUSIONS: These results suggest that G207 should be considered another potential therapeutic agent for renal cell carcinoma.

Animals↗
PubMed2000

Intravesical and intravenous therapy of human bladder cancer by the herpes vector G207.

G207, a conditionally replicating herpes vector, efficiently kills human bladder cancer cells in vitro. To evaluate the therapeutic potential of G207, we have established three in vivo models similar to the clinical situation. In vivo, G207 was intraneoplastically, intravesically, or intravenously inoculated in nude mice. Intraneoplastic inoculation into subcutaneous tumor caused significant tumor growth inhibition. Intravesical inoculation of G207 also caused decreased tumor growth in an orthotopic human bladder cancer model. Furthermore, multiple intravenous inoculation markedly inhibited subcutaneous tumor growth. These results suggest that intravesical therapy with G207 is effective for localized bladder tumor, especially for carcinoma in situ (CIS), and intravenous therapy with G207 is promising for invasive or metastasized bladder tumor.

Animals↗
PubMed2000

Detection of atrazine based on the SPR determination of P450 mRNA levels in Saccharomyces cerevisiae.

We describe a novel method for quantification of atrazine based on detection of P450 mRNA levels in Saccharomyces cerevisiae. The selected oligonucleotide probe exhibited specificity against P450 mRNA and was successfully immobilized on the sensor chip. The mRNA was subsequently quantified by RU change using a SPR system. When the cells were disrupted by boiling, mRNA could be measured without further purification at reduced sensitivity. This simple technique permits the detection of atrazine within 15 min. This rapid and highly sensitive method can be used for the detection of atrazine.

Atrazine↗
PubMed2000

Occurrence of immunoreactive Activin/Inhibin beta(B) in thyrotropes and gonadotropes in the bullfrog pituitary: possible Paracrine/Autocrine effects of activin B on gonadotropin secretion.

Occurrence of immunoreactive activin/inhibin beta(B) in the bullfrog (Rana catesbeiana) pituitary was investigated immunocytochemically by use of antibody against Xenopus activin/inhibin beta(B) subunit. Thyrotropes were demonstrated to contain activin/inhibin beta(B)-immunoreactive substances. Moreover, immunoelectron microscopy revealed that in the secretory granules of thyrotropes and, to a lesser extent, in those of gonadotropes, activin/inhibin beta(B)-immunoreactive substances were present. Based on this observation, we investigated the effect of activin B on the release of gonadotropins from dispersed anterior pituitary cells of the bullfrog. Activin B stimulated the release of not only follicle-stimulating hormone (FSH) but also luteinizing hormone (LH) dose dependently. Under the culture conditions used in this experiment, inhibin B, as well as follistatin, did not affect the basal levels of LH and FSH, but they suppressed the activin-induced release of these hormones. This is the first study on the effect of activin on pituitary hormone secretion in lower tetrapods.

Activins↗
PubMed2000

A novel role of differentiation-inducing factor-1 in Dictyostelium development, assessed by the restoration of a developmental defect in a mutant lacking mitogen-activated protein kinase ERK2.

It has been previously reported that the differentiating wild-type cells of Dictyostelium discoideum secrete a diffusible factor or factors that are able to rescue the developmental defect in the mutant lacking extracellular signal-regulated kinase 2 (ERK2), encoded by the gene erkB. In the present study, it is demonstrated that differentiation-inducing factor-1 (DIF-1) for stalk cells can mimic the role of the factor(s) and the mechanism of the action of DIF-1 in the erkB null mutant is also discussed. The mutant usually never forms multicellular aggregates, because of its defect in cyclic adenosine monophosphate (cAMP) signaling. In the presence of 100 nM DIF-1, however, the mutant cells formed tiny slugs, which eventually developed into small fruiting bodies. In contrast, DIF-1 never rescued the developmental arrest of other Dictyostelium mutants lacking adenylyl cyclase A (ACA), cAMP receptors cAR1 and cAR3, heterotrimeric G-protein, the cytosolic regulator of ACA, or the catalytic subunit of cAMP-dependent protein kinase (PKA-C). Most importantly, it was found that DIF-1 did not affect the cellular cAMP level, but rather elevated the transcriptional level of pka during the development of erkB null cells. These results suggest that DIF-1 may rescue the developmental defect in erkB null cells via the increase in PKA activity, thus giving the first conclusive evidence that DIF-1 plays a crucial role in the early events of Dictyostelium development as well as in prestalk and stalk cell induction.

Animals↗
PubMed2000

Application of conditionally replicating herpes vector for gene therapy treatment of urologic neoplasms.

Herpes vector has been widely used for experimental gene therapy. We herein review the strategies of such therapy for the treatment of urologic neoplasms. Most experimental studies of genetically altered viruses have employed replication-incompetent vectors. However, such viruses are unable to infect additional cells subsequent to the initial infection event. Therefore, this strategy has relied heavily on the bystander effect because a large number of noninfected tumor cells remain. Conditionally replicating herpes vector G207 has been developed in order to overcome potential problems of safety and tumor specificity for human use. It has been used to treat malignant brain tumors because of its neural tropism. In the last few years, applications of G207 for non-neural tumors have been reported. Because G207 may be useful for the treatment of urologic malignant tumors, we evaluated the antitumor effect against several types of tumor cells both in vitro and in vivo. Our data suggest that G207 may be applicable for the treatment of urologic malignant tumors.

Animals↗
PubMed2000

Oncolytic viral therapy for human prostate cancer by conditionally replicating herpes simplex virus 1 vector G207.

Over the last few years, a conditionally replicating herpes simplex virus 1 (HSV-1) vector, G207 has been used for the treatment of several malignant tumors. In this article we evaluate the anti-tumoral effect of G207 against prostate cancer in vitro and in vivo. The susceptibility of the human prostate cancer cell lines, DU145 and PC3 to G207 at a multiplicity of infection (MOI) of 0.1 was examined. In addition, the growth characteristics of G207 were assessed. Athymic mice with s.c. tumors were inoculated in vivo intraneoplastically with 1 x 10(7) plaque-forming units (PFU) of G207. For the pathological analyses, s.c. tumors were stained with X-gal. DU145 and PC3 were efficiently destroyed by G207 within 7 days. The viral yields of G207 increased time-dependently. In vivo, the intraneoplastic inoculation of G207 induced a significant inhibition of the tumor growth. The mean tumor growth ratio was significantly inhibited in the G207-treated tumors (DU145, P < 0.0001; PC3, P < 0.001 versus controls). In a pathological study, many lacZ-positive cells were diffusely present in the G207-treated tumors. G207 showed a significant antitumoral effect against human prostate cancer cell lines, and thus may be considered a useful agent for the treatment of prostate cancer.

Animals↗
PubMed2000

Graft failure of autologous peripheral blood stem cell transplantation due to acute metabolic acidosis associated with total parenteral nutrition in a patient with relapsed breast cancer.

A 32-year-old female had been diagnosed as having relapsed breast cancer and liver metastasis. She underwent high-dose chemotherapy followed by autologous peripheral blood stem cell transplantation (PBSCT) with 5.8 x 10(6)/kg CD34+ cells. She was supported by total parenteral nutrition (TPN) without vitamins throughout these therapies. Hematopoietic recovery was not observed by day 28 after PBSCT, necessitating a second PBSCT on day 29 using the back-up material of 4.4 x 10(6)/kg CD34+ cells. On the next day, she suddenly developed severe metabolic acidosis, heart failure and deep coma. After immediate infusion of thiamine, heart failure and coma rapidly improved. The neutrophil count reached 0.5 x 10(9)/l on day 9 and the platelet count 50 x 10(9)/l on day 15 after the second PBSCT. This is a rare graft failure due to acute metabolic acidosis or thiamine deficiency associated with TPN.

Acidosis↗
PubMed2000

[An elderly patient with myelodysplastic syndrome successfully treated with combination of granulocyte-colony stimulating factor and continuous-drip infusion of low-dose cytarabine and etoposide].

A 73-year-old man was given a diagnosis of myelodysplastic syndrome in October 1997. He was treated with red blood cell transfusion and granulocyte-colony stimulating factor (G-CSF). In February 1998, he was admitted due to progression of pancytopenia. Bone marrow aspiration revealed refractory anemia with excess of blasts in transformation. The patient was treated with continuous-drip infusion of low-dose cytarabine and etoposide with G-CSF (AVG therapy). Complete remission (CR) was obtained after 2 courses of AVG therapy. Non-hematologic adverse effects were mild enough to be tolerated. CR has been maintained for 16 months with 1 course of consolidation therapy and 3 courses of intensification therapy using the AVG regimen.

Aged↗