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H Yabe

Publications and source records attributed to H Yabe.

At least 73 records · Page 4Linked to original sources
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

[Recent progress in treatment and prophylaxis of graft-versus-host disease].

Graft-versus-host disease (GVHD) is one of major causes of mortality in allogeneic bone marrow transplantation (BMT). GVHD prophylaxis for HLA matched sibling BMT is widely done by methotrexate and/or cyclosporine. More intensive modalities are necessary for HLA mismatched related or HLA matched unrelated BMT; T cell depletion, ALG/ATG in preconditioning or following BMT and FK-506 with short term methotrexate are currently used with certain success. Moderate to severe GVHD may develop despite of these preventions, and standard to high dose of steroid with or without ALG/ATG is currently used as the first line therapy. GVHD, however, is an important component to cure malignant diseases through its anti-tumor effect called graft-versus-leukemia (GVL) effect. Several attempts have been made to induce mild to moderate GVHD both in allogeneic and in autologous BMT; low dose of cyclosporine, IL-2, ubenimex and donor buffy coat or peripheral lymphocyte transfusion are shown to be effective with some limitation.

Bone Marrow Transplantation↗
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↗
PubMed1994

The strategy to treat disseminated neuroblastoma utilizing bone marrow transplantation: what is the surgeon's role?

The current role of surgery was evaluated in seven consecutive patients with high-risk neuroblastoma (six stage 4 patients and one stage 3, abdominal origin, and all over 12 months of age at diagnosis) treated with new modalities utilizing bone marrow transplantation (BMT). In six of these seven patients, a grossly complete excision of the primary tumor was achieved, and four have survived for 133, 69, 39, and 28 months with no further evidence of disease. The remaining patient with celiac neuroblastoma only underwent a biopsy during a second-look laparotomy after chemoradiotherapy, and thereafter developed local and distant recurrences and ultimately succumbed to the tumor. The timing of surgical intervention varied, either before or after chemotherapy, and did not appear to affect the ultimate survival. Although surgical excision of the primary tumor remains a very high priority in the overall treatment scheme, the most important factor remains the eradication of the tumor by well-planned courses of intensive chemotherapy (e.g., A1 Protocol of the Study Group of Japan). Thus, after having induced complete remission, for consolidation, it is necessary to kill all remaining tumor cells by giving supralethal doses of chemotherapy including total body irradiation (TBI) assisted by BMT.

Adrenal Gland Neoplasms↗
PubMed1994

Changes in hypothalamic-pituitary function following bone marrow transplantation in children.

Patients who undergo bone marrow transplantation (BMT) frequently experience impaired pituitary function, but precise assessment using repeated provocative tests has not been described. We studied 32 children (16 boys) who had BMT after receiving preparative irradiation. Assessment of pituitary function was performed by infusing insulin, luteinizing hormone-releasing hormone (LHRH), and thyrotropin-releasing hormone (TRH) on several occasions at various intervals during the follow-up period. Serum free thyroxine (FT4) and thyrotropin (TSH) levels tended to be low during the early period following BMT. Serum FT4 concentrations reverted to the low-normal range 1 year after transplant, and eight of 29 patients had subnormal and delayed TSH response to TRH consecutively. No children showed overt hypothyroidism. Basal and peak serum gonadotropin levels in response to LHRH were elevated in the patients who had received transplant around the time of puberty. Leydig cell function assessed by human chorionic gonadotropin test was normal. Three girls experienced menarche, and one male patient fathered a normal boy 7 years after BMT. Pituitary-adrenal function and prolactin secretion were not affected. A high incidence of transient hypothyroidism which did not require replacement therapy and gonadal failure among pubertal children were observed. Shielding of gonads should be attempted, if possible, at the time of preparative irradiation to prevent resultant hypogonadism.

Adolescent↗
PubMed1994

Transition of T cell receptor gamma/delta expressing double negative (CD4-/CD8-) lymphocytes after allogeneic bone marrow transplantation.

We studied peripheral blood CD4-CD8- gamma/delta T cells in recipients of allogeneic marrow grafts, using three-color immunofluorescence and flow cytometry, and investigated changes in their numbers in relation to the administration of hematopoietic growth factors or chronic graft-versus-host disease (GVHD). In the early post-bone marrow transplantation (BMT) period, the relative and absolute numbers of peripheral CD4-CD8- gamma/delta T cells in 22 allogeneic marrow graft recipients in relation to the use of hematopoietic growth factors were studied. During the first 4 weeks, increased numbers of CD4-CD8- gamma/delta T cells were observed in recipients of either recombinant human granulocyte colony-stimulating factor (rhG-CSF) or granulocyte macrophage colony-stimulating factor (GM-CSF). However, 4-8 weeks after BMT, the number of these cells was similar in both groups whether or not growth factors had been administered. At a later stage after BMT (3-12 months), peripheral CD4-CD8- gamma/delta T cells from 43 allogeneic BMT recipients were studied. These cells were markedly decreased in patients with chronic GVHD, and this decrease correlated closely with the clinical signs of chronic GVHD. These results suggest that CD4-CD8- gamma/delta T cells may play an important role in the recovery of neutrophils associated with growth factors during the very early post-BMT period, and in the immunodeficient state of chronic GVHD at a later stage after BMT.

Adolescent↗
PubMed1993

Median method for detecting endogenous event-related brain potentials.

Most studies of event-related brain potentials (ERPs) use the averaging method. This procedure is assumed to increase signal/noise ratio in proportion to the square root of the number of trials if the signal is invariant and the noise is stationary. In addition, the averaged value is the appropriate measure of central tendency if the measurements have a Gaussian distribution. For endogenous ERPs, however, application of the averaging method encounters 3 serious problems. First, the invariance of signal cannot always be assumed because the endogenous signal reflects psychological processes which may be missing in some trials. Secondly, the Gaussian distribution cannot be assumed when a small number of trials is averaged. Thirdly, averaging a limited number of trials is sensitive to inclusion of occasional, non-random, noise. The characteristics of the median ERP can address all 3 problems. These characteristics are demonstrated by an original equation.

Brain↗
PubMed1993

Rapid detection of Mycoplasma pneumoniae in clinical samples by the polymerase chain reaction.

A DNA amplification method was used to detect Mycoplasma pneumoniae in clinical samples. M. pneumoniae 16S ribosomal RNA gene sequences were selected as the amplification target region. The polymerase chain reaction (PCR) with purified DNA fragments as templates yielded an expected 88-bp fragment from M. pneumoniae but not from other Mycoplasma spp. nor from any of the other bacteria assayed. With this method, the 88-bp product specific for M. pneumoniae could be obtained from a minimum of 0.05 pg of M. pneumoniae DNA. Subsequently this PCR technique was used for the detection of M. pneumoniae in throat-swab samples. Twenty-two of 30 culture-positive clinical samples gave positive results in the PCR test. Thirty-two culture-negative clinical samples and 33 samples from healthy volunteers, of which only one was culture-positive, gave negative results in the same PCR test. This PCR method is useful for the direct detection of M. pneumoniae in clinical samples.

Base Sequence↗
PubMed1993

Growth and growth hormone secretion in children after bone marrow transplantation.

Long-term sequelae of bone marrow transplantation (BMT) are a major concern among long-term survivors since the procedure has been considerably developed over the past decade. In this study, linear growth and growth hormone (GH) secretion were evaluated in 25 children (14 males and 11 females) with various neoplastic or non-neoplastic hematological disorders who had survived for more than 3 years after BMT. Impaired linear growth after BMT, as defined by a change in height standard deviation score (SDS) by more than -1.0 SD, was observed in 14 patients (56%). Four children showed severe growth suppression with a decrease in SD score by more than 2.0, and 10 exhibited a moderate reduction by between 1.0 and 2.0 SD. A recovery of normal height velocity was observed in those who had received BMT at a younger age. The type of disease, a difference in preconditioning regimen, the presence of chronic graft-versus-host disease or a GH secretory capacity 1 year after BMT were not contributing factors for impaired growth. A serial examination of GH secretion with insulin-induced hypoglycemia demonstrated that poor GH secretion was not necessarily a prerequisite for impaired growth. These results indicate that the secretory status of GH does not predict the future growth pattern of children who received BMT.

Adolescent↗
PubMed1993

Bone marrow transplantation for Fanconi anemia. Adjustment of the dose of cyclophosphamide for preconditioning.

PURPOSE: Five patients with Fanconi anemia have been treated by bone marrow transplantation. PATIENTS AND METHODS: They were conditioned with cyclophosphamide (CY) (20-150 mg/kg), antilymphocyte globulin, and thoracoabdominal irradiation (4-6 Gy). The dose of CY for preconditioning was adjusted individually, based on the in vitro effect of CY metabolites on the chromosomes of patients with Fanconi anemia. Four patients received marrow from human leukocyte antigen (HLA)-identical siblings, and one received marrow from his HLA phenotypically identical father. RESULTS: All patients achieved engraftment, and acute graft-versus-host disease (GVHD) grade II or more was not observed. Three developed chronic GVHD. All patients are surviving 2-5 years after grafting, with hematological improvement. CONCLUSIONS: These results indicate that the individual dose adjustment of CY used for preconditioning may prevent graft failure and severe acute GVHD.

Anemia, Aplastic↗
PubMed1992

A case of CREST syndrome with rapidly progressive liver damage.

A patient with CREST syndrome (calcinosis cutis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia) who had severe jaundice (total bilirubin 29.1 mg/dl) and rapidly progressive liver damage is reported. The liver damage findings matched the criteria of autoimmune chronic active hepatitis (CAH). There have been no prior reports of a case of CREST syndrome with autoimmune CAH in Japan. Anticentromere antibody (ACA) was detected in the serum; ACA seemed to be related to the pathogenesis of these two diseases.

Autoantibodies↗
PubMed1992

[Frequency of the development of RNA-rich reticulocytes in allogeneic bone marrow transplant recipients].

We measured appearance rates of RNA-rich reticulocytes in 8 patients undergoing allogeneic bone marrow transplantation, using a Sysmex R-1000 reticulocyte counter which utilizes laser flow cytometry. The changes in proportion of RNA-rich reticulocytes (high fluorescence ratio: HFR) and maturation index (MI: HFR + middle fluorescence ratio/low fluorescence ratio) were compared with those of WBC, neutrophil or reticulocyte counts. Engraftment was defined as an HFR of greater than or equal to 5% or a MI of greater than or equal to 15%. Engraftment was confirmed significantly earlier by HFR (13.5 +/- 2.4 days) and MI (13.1 +/- 2.9 days) than by neutrophils (17.1 +/- 3.2 days) or reticulocytes (20.4 +/- 6.2 days). The maturation of reticulocytes would be a useful indicator for engraftment or recovery from marrow aplasia in cases of bone marrow transplantation.

Adolescent↗
PubMed1992

Protective effect of probucol on ischemia-reperfusion arrhythmias in the rat heart.

OBJECTIVE: To evaluate the efficacy of probucol on ischemia-reperfusion injury in the isolated working rat heart. DESIGN: Twelve male Sprague-Dawley rats were divided into two groups: one was fed normal chow (group C) and the other was fed chow containing 1% probucol for four weeks (group P). Samples of heart organ and blood were then taken under anesthesia. Isolated hearts were perfused in a working heart model. After 5 mins of perfusion in aerobic conditions, global ischemia was induced for 15 mins, the hearts were then reperfused. Aortic and coronary flow, cardiac function and electrocardiogram were monitored throughout the experiment, including a 20 min period of reperfusion. Serum lipids and lipid peroxide were also measured in each rat. RESULTS: Rats in group P (probucol-treated) had significantly lower levels of serum cholesterol, triglyceride and phospholipid than those in group C (controls). Serum lipid peroxide was also significantly lower in group P than in group C rats (P < 0.05). The incidence of ventricular arrhythmias in the ischemia and reperfusion stages was lower in group P than in group C (P < 0.001) and the increase in coronary flow during the reperfusion stage was greater in isolated hearts of group P rats than in those of group C (P < 0.05). CONCLUSIONS: Probucol may have a protective effect on myocardium with respect to ischemia-reperfusion arrhythmia in the isolated rat heart, presumably due to an antioxidative effect.

Animals↗
PubMed1992

[A juvenile case of mesenchymal chondrosarcoma originating from soft tissue in the orbit].

Mesenchymal chondrosarcoma is a very rare occurrence in the orbit. A 10-year-old girl presented with right exophthalmos. Computed tomography revealed a round tumor inside the muscular cone of the right orbit. There was a sign of slight calcification inside the tumor. The tumor was surgically removed by the Krönlein-Berke procedure. Histopathological examination showed undifferentiated mesenchymal cells and cartilage tissue. A recurrent tumor was found in the same location 34 months after the surgery, which was removed by frontal approach saving the globe with normal function. Histopathology of the recurrent tumor revealed a slight difference from the primary tumor, showing hemangiopericytoma pattern without cartilage components. Immunohistochemical studies of the primary and recurrent tumors showed their cells to be positive for antifactor VIII and S-100, and negative for myoglobin and monoclonal antibody to muscle actin. Electron microscopically these undifferentiated cells had large nucleus and very scanty cytoplasm, mostly containing glycogen granules. This is probably the first description of a juvenile case of mesenchymal chondrosarcoma originating from soft tissue in the orbit.

Child↗