Biomedical subjects

M Yabe

Publications and source records attributed to M Yabe.

At least 37 records · Page 2Linked to original sources

PubMed1998

MIB-1 and p53 immunocytochemistry for differentiating pilocytic astrocytomas and astrocytomas from anaplastic astrocytomas and glioblastomas in children and young adults.

AIMS: To establish whether MIB-1 and p53 staining are useful for differentiating pilocytic astrocytomas and astrocytomas from anaplastic astrocytomas and glioblastomas. This study was restricted to children and young adults under 30 years of age because of the differences in p53 mutations between paediatric and adult astrocytomas. METHODS AND RESULTS: Forty-five astrocytic tumours, including 18 pilocytic astrocytomas, 14 astrocytomas, four anaplastic astrocytomas and nine glioblastomas, from 45 children and young adults, between 1 and 29 years (mean 11 years) of age, were examined pathologically, and sections from paraffin-embedded blocks were used for MIB-1 and p53 immunostaining. The MIB-1 labelling index and the frequency and intensity of p53 staining in both the pilocytic astrocytoma and the astrocytoma group were significantly lower than in the anaplastic astrocytoma plus glioblastoma group (P < 0.001). In 11.1% (two of 18) of pilocytic astrocytomas and 42.9% (six of 14) of astrocytomas, immunoreactivity of either MIB-1 or p53 staining was of almost the same intensity as that of anaplastic astrocytomas and glioblastomas. However, in these cases, results using both MIB-1 and p53 stain differed from those for anaplastic astrocytomas and glioblastomas. CONCLUSIONS: MIB-1 and p53 co-staining is very useful for differentiating pilocytic astrocytomas and astrocytomas from anaplastic astrocytomas and glioblastomas. However, MIB-1 or p53 staining alone cannot differentiate pilocytic astrocytomas and astrocytomas from anaplastic astrocytomas and glioblastomas.

Adolescent↗

PubMed1998

The effects of intrinsic nitric oxide on cardiac neural regulation in cats.

UNLABELLED: In this study, we aimed to elucidate the effects of intrinsic nitric oxide (NO) on cardiac neural regulation. Twenty-two cats were anesthetized with 1.5% isoflurane and allocated to Group I (intact; n = 7), Group D (denervated baroreceptors and vagi; n = 8), or Group B (autonomic blockade with i.v. hexamethonium, propranolol, and atropine; n = 7). Cardiac sympathetic nerve activity (CSNA), mean arterial pressure (MAP), sinus heart rate (HR), and A-H and H-V intervals during pacing (150 bpm) were measured before and after i.v. administration of a NO synthase inhibitor, NG-nitro-L-arginine (L-NNA, 30 mg/kg) and after reversal with an excessive dose of L-arginine (300 mg/kg), before and during intermittent electrical stimulation of the posterior hypothalamus. L-NNA significantly increased MAP in Groups I and B, but not in Group D. L-NNA significantly decreased HR and lengthened A-H in Group I, but not in other groups. L-arginine further decreased HR and lengthened A-H unexpectedly. The reasons for these findings could not be determined in this study. L-NNA did not change CSNA. Hypothalamic stimulation did not potentiate L-NNA-induced changes in CSNA, hemodynamic variables, and atrioventricular conduction. In conclusion, intrinsic NO may modulate atrioventricular conduction and sinus rate through a vagal cholinergic, rather than a nonautonomic mechanism. IMPLICATIONS: Elucidating the roles of intrinsic nitric oxide (NO) on cardiac neural regulation is important. In intact, vagotomized, and baroreceptor-denervated or pharmacologically autonomic blockaded cats, an NO synthesis inhibitor was administered, and atrioventricular conduction and cardiac sympathetic neural discharge were measured. The results suggest a vagal cholinergic mechanism of intrinsic NO.

Anesthetics, Inhalation↗

PubMed1998

Contamination of mouse-adapted influenza virus with Sendai virus.

In our laboratory animal facility, Sendai virus (HVJ) contamination occurred in a negative flow rack used for experimental infection with 4 strains of mouse-adapted influenza virus (Inf.V). Anti-HVJ antibody (Ab) was detected in 35/42 mice in the rack. To specify the strain of Inf.V contaminated with HVJ, experimental infection was performed by using A, B and D strains of Inf.V in each vinyl isolator. Anti-HVJ Ab was detected in all mice infected with A strain at day 28 post-infection. As a result of experimental infection with A strain of Inf.V which was treated with anti-HVJ mouse serum, the virus suspension was determined not to contain HVJ and allowed for experimental use in our facility, Since then, HVJ contamination has not occurred in our facility.

Animals↗

PubMed1998

Application of nested polymerase chain reaction to detection of mouse hepatitis virus in fecal specimens during a natural outbreak in an immunodeficient mouse colony.

The usefulness of RT-PCR for the detection of MHV in tissues and feces of experimentally infected animals has been reported, but it was unclear whether the method was also applicable for the detection of MHV during a natural outbreak. Enterotropic infection is considered to be the most common form of natural infection among various forms of MHV infection. In this paper, RT-nested PCR was performed to detect MHV excreted in the feces during an outbreak in an immunocompromised A/WySnJ mouse colony. The expected bands were amplified after nested PCR from 20 fecal samples out of 37. These results showed that RT-nested PCR could be applicable for the diagnosis for MHV natural infection.

Animals↗

PubMed1998

[Allogeneic bone marrow transplantation in children from related donors other than HLA-identical siblings].

Thirty-five children with poor-prognosis disease underwent allogeneic bone marrow transplantation (BMT) from related donors other than HLA identical siblings (parents in 18 cases, non-identical siblings in 14, and other relatives in 3). Phenotypically identical donors were involved in 12 cases, donors with one mismatched locus in 17, and donors with two or more mismatched loci in 6. Thirty-two of the children received total-body irradiation as part of their conditioning regimen, followed by unpurged marrow-cell infusions (averaging 4.09 x 10(8) cells/kg). Methotrexate and cyclosporin were administered for graft-versus-host disease (GVHD) prophylaxis; 15 of the children also received antithymocyte globulin (ATG) infusions. The effective graft rate for the group was 84. 8%; of 5 patients who experienced rejections, 4 had non-malignant diseases. The incidence of grade II-IV acute GVHD was 48.4%, significantly higher than that for groups that received allogeneic BMT from matched sibling donors. Three children (8.8%) died of severe GVHD. The incidence of acute GVHD in phenotypically matched patients was the same as that in the one-locus mismatched cases. MLC reactivity affected the incidence of acute GVHD (60.0% MLC-positive, 28.6% negative). ATG reduced the severity of acute GVHD. The event-free survival rate was 40.8 +/- 8.5% for the entire group (N = 35; 32.9 +/- 10.5% for the 22 children with malignancies, and 53.8 +/- 13.8% for the 13 with non-malignant diseases). Despite the risk of severe GVHD, allogeneic BMT from related donors other than HLA-identical siblings seems to be an effective treatment for patients with poor-prognosis diseases.

Acute Disease↗

PubMed1997

Acquired fusion activity of a murine coronavirus MHV-2 variant with mutations in the proteolytic cleavage site and the signal sequence of the S protein.

The spike (S) protein of a nonfusogenic murine coronavirus, MHV-2, was compared to the S protein of a variant with fusion activity, MHV-2f. Two amino acids differed between the S proteins of these viruses; one was located in the signal sequence and the other was in the putative cleavage site. The amino acid at position 12 in the signal sequence was S in MHV-2 and C in MHV-2f. The amino acid sequence of the cleavage site of MHV-2 was HRARS, while that of MHV-2f was HRARR, showing one amino acid replacement at position 757. In DBT cells infected with MHV-2, the S protein was not cleaved, while the S protein of MHV-2f was cleaved. The S protein of MHV-2f expressed in a transient vaccinia virus expression system was cleaved and was fusogenic in contrast to the nonfusogenic activity of uncleaved MHV-2 S protein. Because the signal sequence is assumed to be removed from the mature S protein soon after synthesis, and because the S protein of MHV-2 was expressed on the cell surface in the same way as the S protein of MHV-2f, the difference in the signal sequence seemed to have had little effect on the transportation and the fusion activity of the S protein. These results showed that MHV-2 does not fuse cells due to the lack of cleavage of its S protein. This conclusion differs from studies on the activity of syncytium formation by the S proteins of fusogenic MHV-JHM and -A59 strains. Possible reasons for these differences in fusion activity are discussed.

Binding Sites↗

PubMed1997

Fatal interstitial pulmonary disease in a patient with dyskeratosis congenita after allogeneic bone marrow transplantation.

Chronic restrictive lung disease in a 9-year-old boy with dyskeratosis congenita (DC) 7 years after allogeneic bone marrow transplantation (BMT) is described. When he was 1 year and 10 months old, severe aplastic anemia developed. He received a marrow transplant from his HLA serologically identical, but HLA-DP mismatched brother. He developed grade II acute graft-versus-host disease (GVHD) and thereafter chronic GVHD of progressive type, and was treated with both prednisolone and azathioprine resulting in clinical improvement. Thereafter he complained of dyspnea, and bilateral noncircumscribed interstitial shadows on chest CT scan were present. His pulmonary function showed restrictive changes. Prednisolone was not effective and he died of respiratory failure. Post-mortem examination confirmed interstitial fibrosis, lymphocytic infiltration of the bronchioles and alveoli with luminal fibrosis. There was no evidence of chronic GVHD in the skin and the liver. These findings raise the possibility that this pulmonary complication was associated with DC itself.

Anemia, Aplastic↗

PubMed1997

Molecular cloning and expression of cynomolgus monkey interleukin-2 cDNA by the recombinant baculovirus system.

The cDNA encoding interleukin-2 (IL-2) of cynomolgus monkey was molecularly cloned from concanavalin-A-stimulated peripheral lymphocyte cDNA by the reverse transcription-polymerase chain reaction method. Cynomolgus monkey IL-2 cDNA displays a high degree of homology with the human equivalent both at nucleic acid (98%) and amino acid (96%) sequence levels, although having only one additional amino acid residue. Recombinant monkey IL-2 secreted by insect cells infected with the recombinant baculovirus migrated as two distinct bands with 15 and 18 kD corresponding to mature and precursor IL-2 molecules, respectively, which were revealed to cross-react with anti-human IL-2 polyclonal antibody in Western blot analysis. This monkey IL-2 exhibited high biological activity up to an order of 10(6) U/ml as assessed by an IL-2-dependent cell proliferation assay and was shown to be neutralized by anti-human IL-2 antibody.

Amino Acid Sequence↗

PubMed1997

[Intraoperative continuous epidural lidocaine combined with preoperative administration of epidural morphine for post-hepatectomy pain relief].

In a randomized double-blind study, the use of continuous epidural lidocaine during surgery combined with preoperative epidural morphine was compared with that of preoperative epidural morphine alone for postoperative analgesia in 20 patients undergoing hepatectomy. Morphine 2 mg was administered through a catheter inserted epidurally at T10-11 before surgery, followed by continuous epidural administration of 1% lidocaine 5ml.h-1 in group Lid (n = 10) or normal saline 5ml.h-1 in group NS (n = 10) during surgery. Anesthesia was maintained with N2O-O2-isoflurane in both groups. On admission to the ICU, the visual analog scale score (VAS; mm) was 20 +/- 7 (mean +/- SE) in group Lid and 38 +/- 10 in group NS, and the number of patient with VAS < or = 30 was 9 in group Lid and 4 in group NS; these differences were significant (P < 0.05). Pain score during mobilization in group Lid was significantly lower than that in group NS (P < 0.05). All patients in both groups had adequate analgesia for the remainder of their stay in the ICU. No patient had any serious adverse effect. We conclude that continuous epidural administration of lidocaine during hepatectomy combined with administration of epidural morphine just before surgery results in better pain relief during the early postoperative period than that obtained with epidural morphine alone, and is without serious side effects.

Aged↗

PubMed1997

[Umbilical cord blood transplantation for a patient with Diamond-Blackfan syndrome].

A five-year-old girl with Diamond-Blackfan syndrome received cord blood transplantation from an HLA-identical sibling. The patient showed pale face at birth, and was diagnosed to have Diamond-Blackfan syndrome. She had been treated with prednisolone (PSL), high dose of methylprednisolone, erythropoietin, and anti-lymphocyte globulin. Despite of these intensive therapies, erythropoiesis did not entirely improve, and transfusion of red blood cells had been required every third or fourth week until cord blood transplantation. Conditioning regimen consisted of thoraco-abdominal irradiation (TAI; 8 Gy), cyclophosphamide (CY; 50 mg/kg x 4), and anti-thymocyte globulin (ATG; 2.5 mg/kg x 4), Cyclosporin (CyA 3 mg/kg) was administered for the prophylaxis of graft-versus-host disease (GVHD). 4.14 x 10 (7)/kg of cord blood mononuclear cells were infused to the patient. White blood cell (WBC) and reticulocyte counts increased promptly, but recovery of platelet count was delayed. Skin GVHD (grade I) appeared on day +9, which responded to the administration of PSL (2 mg/kg). Chromosomal analyses of bone marrow cells for sex mismatch revealed complete chimerism on day +14, on day +28 and thereafter. Umbilical cord blood cells can be an alternative source of hematopoietic stem cells for allogeneic transplantation.

Child, Preschool↗

PubMed1997

[Anesthetic management of cesarean section in a patient with pulmonary embolism due to deep venous thrombosis].

A 28-year-old primipara with pulmonary embolism due to deep venous thrombosis was scheduled for cesarean section under general anesthesia. Her Swan-Ganz catheter and blood gas data revealed pulmonary hypertension and hypoxemia, respectively. Heparin was discontinued 6 hours before operation. A transesophageal echocardiogram (TEE) probe and an inferior vena cava filter were inserted before surgery. Anesthesia was maintained with nitrous oxide and isoflurane in oxygen before delivery, and after delivery with nitrous oxide in oxygen, fentanyl and midazolam. Nitroglycerin and prostaglandin E1 were administered before and after delivery, respectively, to control pulmonary artery pressure, although they were not effective. The anesthetic course was uneventful and her baby's Apgar scores were satisfactory. Mean pulmonary artery pressure (MPAP) gradually decreased after surgery. The inferior vena cava filter may be effective in preventing new pulmonary embolism, and MPAP and TEE monitoring are useful for early detection of pulmonary emboli.

Adult↗

PubMed1996

The effects of dobutamine and phenylephrine on atrioventricular conduction during combined use of halothane and thoracic epidural lidocaine.

The purpose of this study was to measure cardiac sympathetic nerve activity (CSNA) and atrioventricular (AV) conduction and to test the effects of dobutamine (DOB) and phenylephrine (PHE) on AV conduction during combined use of halothane and thoracic epidural lidocaine. Cats were anesthetized with 1 % halothane and an epidural catheter was inserted through T-9 laminectomy. His bundle and atrial electrocardiograms were obtained and atrial electric stimulation was performed using quadripolar catheter electrodes. Cats underwent left thoracotomy, and CSNA was recorded directly from the left ventrolateral or ventromedial nerve. In addition to sinus cycle length (SCL) measurement during spontaneous beating, the functional refractory period (FRP) of the atrioventricular node (AV node), effective refractory period (ERP) of the atrium, atrium-His (A-H) intervals were determined just before and 10, 20, and 30 min after epidural administration of 1% lidocaine (0.2 mL/kg) in Group C. DOB 5 micrograms/kg/min (Group DOB) and PHE 0.5-1.0 micrograms/kg/min (Group PHE) were intravenously administered from 12 to 22 min after epidural lidocaine. CSNA and mean arterial pressure (MAP) were markedly decreased and SCL, FRP of AV node, ERP of atrium and A-H interval were significantly prolonged after epidural lidocaine. MAP increased to baseline level during DOB or PHE infusion. Worsening of cardiac electrophysiological variables was improved with DOB infusion, but did not change with PHE infusion. We conclude that thoracic epidural lidocaine during halothane anesthesia almost eliminates CSNA, and thereby attenuates sinus node automaticity and AV node function. DOB restored normal cardiac electrophysiological variables, and therefore is preferable to phenylephrine as a pressor drug.

Adrenergic alpha-Agonists↗

PubMed1996

A Japanese boy with myalgia and cramps has a novel in-frame deletion of the dystrophin gene.

We report a Japanese Becker muscular dystrophy (BMD) patient with occasional myalgia and cramps during normal activity that developed at the age of 28 months. His family history was negative for neuromuscular diseases. Muscle biopsy analyses, including dystrophin immunostaining, disclosed no clinically relevant findings. The diagnosis of BMD was initially made at the age of 10 years, when indications of persistent high serum levels of CK prompted us to screen deletions in the dystrophin gene by amplification of 19 deletion-prone exons from the genomic DNA by the polymerase chain reaction (PCR). Among the exons examined, exons 13 and 17 were deleted. To clarify the size of the deletion, the dystrophin transcript was analyzed by reverse transcription PCR. The determined nucleotide sequence of the amplified product encompassing exons 10 to 20 disclosed that the entire segment corresponding to exons 13 to 18 (810 bp) was absent, a deletion that would be expected to cause the production of a dystrophin protein lacking 270 amino acids from the rod domain. This result indicates that occasional myalgia and cramps could be early clinical manifestations of mild BMD, especially in patients who have a deletion in the rod domain, and that deletion screening of the dystrophin gene might be the only reliable method to diagnose such cases.

Base Sequence↗

PubMed1996

Successful engraftment of allogeneic CD34-enriched marrow cell transplantation from HLA-mismatched parental donors.

The CD34 antigen is expressed on pluripotent stem cells and the CD34+ cell has been shown to be capable of hematopoietic reconstitution in animal and human autologous grafts. We asked if CD34+ cells could reconstitute hematopoiesis in human allogeneic transplantation from a HLA-mismatched donor. Three pediatric patients with advanced leukemia received allogeneic CD34-enriched marrow cell graft from HLA two (two patients) or three (one patient) loci-mismatched parental donors. CD34+ cell selection was performed with mouse anti-CD34 antibody 9C5 and magnetic beads coated sheep anti-mouse IgG1. 1.53 to 2.48 x 10(9) marrow cells were processed and 2.53 to 7.89 x 10(7) positively selected cells were recovered. The selected population showed 93.7 to 99.0% CD34+ cells and total recovery of CD34+ cells from the starting population was 54.6 to 62.3%. CD34+ cell selection resulted in more than 99.9% depletion of CD5+ cells from the bone marrow. The patients received 2.53 to 7.25 x 10(6) CD34-enriched cells/kg after myeloablative therapy. All patients achieved trilineage engraftment that was confirmed by various genetic markers. Acute graft-versus-host disease (GVHD) was grade 0 (two patients) or grade I (one patient), and hematological recovery was successfully achieved as follows; the days to reach granulocytes over 0.5 x 10(9)/I were 11 to 13 days, reticulocytes over 2% was 18 to 28 days, platelets over 50 x 10(9)/I was 33 to 58 days. One patient is surviving without relapse of leukemia and two patients died after either mixed hematopoietic chimerism or leukemia relapse was observed. These studies suggest that CD34+ marrow cells are capable of hematopoietic reconstitution from HLA two or three loci-mismatched donors even with the lowest dose of mature T cells.

Adult↗

PubMed1996

[Direct detection of human cytomegalovirus in urine specimens from bone marrow transplant patients by polymerase chain reaction].

Human cytomegalovirus (HCMV) infection is a major causative life-threatening agent that results in opportunistic infections in bone marrow transplant patients. Since antiviral therapy is available for severe HCMV infections, methods to rapidly identify infected patients are needed so that therapy can be promptly instituted. In this study, we used direct method to detect HCMV in urine specimens by nested polymerase chain reaction (nested-PCR) to monitor urinary excretion of HCMV in patients undergoing bone marrow transplantation. The viral DNA was amplified directly from preheated urine without further treatment prior to amplification. Five microliter of urine proved to give the most efficient amplification. The detection limit of the PCR assay for detection of HCMV was 10 copies/microl. The positive rate of the PCR assay and the tissue culture method for detection of HCMV were 15 of 61 (24.6%) and 4 of 61 (6.6%), respectively. Sensitivity and specificity of the PCR assay were 100% and 81% respectively. Based on these data, urinary excretion of HCMV in 21 patients undergoing bone marrow transplantation were monitored weekly by the PCR assay. As a result, in addition to a higher sensitivity, the PCR assay allowed to identify HCMV infection 3.1 (1 approximately 5) weeks earlier than culture method or antibody elevation. Repeated monitoring of virus excretion by this rapid and simple method was useful to promptly detect HCMV infection, allowing proper institution of antiviral drug therapy in patients undergoing bone marrow transplantation.

Adolescent↗

PubMed1996

[Cord blood stem cell transplantation for a patient with acute myelogenous leukemia (M1)].

A five-year-old boy with acute myelogenous leukemia in relapse was treated by HLA-matched cord blood stem cell transplantation. The patient was preconditioned with 16 mg/kg of busulfan, 15 mg/kg of thiotepa and 90 mg/kg of cyclophosphamide and 2.45 x 10(7)/kg of cord blood mononuclear cells were infused to the patient on October 19th 1995 without the prophylaxis of graft-versus-host disease (GVHD). From the fifth day following the transplant, rG-CSF was administered at a dose of 300 micrograms/m2/day. Hematopoietic recovery was obtained as following; WBC over 1000/microliters was on +18 day, neutrophil over 500/microliters was on +20 day, reticulocyte over 20/1000 was on +28 day and platelet over 50 x 10(2) microliters was on +91 day. Engraftment was confirmed by DNA restriction fragment length polymorphism (VNTR) on +28 day. In spite of absence of prophylaxis of GVHD, the patient did not develop any signs of GVHD, and leukemia relapsed on +105 day. The patient died of leukemia relapse on +251 day. This is the first case of cord blood stem cell transplantation in Japan.

CD4-CD8 Ratio↗

PubMed1995

Bispecific antibody-mediated cytotoxicity by CD4+ and CD8(+)-activated T cells generated from leukemia patients after allogeneic bone marrow transplantation.

The F(ab')2 bispecific antibody (BSAb) was prepared from anti-CD3 moAb and anti-CD10 moAb. The BSAb could react with both CD3+ T cells and CD10+ leukemia cells and triggered T cell-mediated cytotoxicity. To apply the BSAb to prevention of leukemic relapse after BMT, we investigated the generation of both CD4+ and CD8+ anti-tumor effector T cells from patient's PBMC 14 days after BMT. Neither CD4+ T cells nor CD8+ T cells, which were activated with immobilized anti-CD3 moAb plus IL-2, could lyse CD10+ leukemia cells by themselves, but they showed augmented cytotoxicity against CD10+ leukemia cells by targeting with anti-CD3 x anti-CD10 BSAb. Moreover, the activated CD4+ T cells were demonstrated to produce IL-2 and IFN-gamma when they were cultured with CD10+ leukemia cells in the presence of the BSAb. The BSAb-mediated cytotoxicity of activated T cells was demonstrated not only against the recipient leukemia cells but also against third party leukemia cells. These results suggested that anti-CD3 x anti-CD10 BSAb might be a good tool to prevent relapse after BMT in combination with activated CD4+ T cells and CD8+ T cells.

Antibodies, Monoclonal↗

PubMed1995

Successful allogeneic bone marrow transplantation in a case with myelodysplastic syndrome which developed following Fanconi anemia.

We report the case of a 14-year-old boy with myelodysplastic syndrome (MDS/RAEB) which developed following Fanconi anemia. The patient received BMT from an HLA-identical sister. Based on the in vitro CY-sensitivity test, 100 mg/kg of CY was administered for conditioning combined with 6 Gy TBI. Mucosal symptoms such as stomatitis, diarrhea and hematuria were severe, but manageable, and engraftment was successful. The patient has maintained normal trilineage hematopoiesis with > 90% Karnofsky score for 30 months with disappearance of a clonal chromosomal abnormality (47,XY, +i(lq)) which was detected before BMT.

Adolescent↗