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H Yabe

Publications and source records attributed to H Yabe.

At least 19 recordsLinked to original sources
PubMed2001

Organizing sound sequences in the human brain: the interplay of auditory streaming and temporal integration.

The present study examined the relationship between two of the early brain processes of sound organization: auditory streaming and the temporal window of integration (TWI). Presented at a fast stimulus delivery rate, two tones alternating in frequency are perceived as separate streams of high and low sounds. However, when two sounds are presented within a ca. 200 ms temporal window, they are often processed as a single auditory event. Both stream segregation and temporal integration occur even in the absence of focused attention as was shown by their effect on the mismatch negativity (MMN) event-related potential. The goal of the present study was to determine the precedence between these two sound organization processes by using the stimulus-omission MMN paradigm. Infrequently omitting one stimulus from a homogeneous tone sequence only elicits an MMN when the stimulus onset asynchrony separating successive tones is shorter than 170 ms. This demonstrates the effect of the TWI. Magnetic brain responses elicited by infrequent stimulus omissions appearing in a sequence of two alternating tones were recorded. The magnetic MMN was elicited by tone omission when the alternating tones formed a single stream (with no or only small frequency separation between the two tones) but not when separate high and low streams emerged in perception (large frequency separation between the two alternating tones). This result shows that auditory streaming takes precedence over the processes of temporal integration.

Acoustic Stimulation↗
PubMed2001

Allogeneic bone marrow transplantation in first remission rescues children with Philadelphia chromosome-positive acute lymphoblastic leukemia: Tokyo Children's Cancer Study Group (TCCSG) studies L89-12 and L92-13.

BACKGROUND: The prognosis of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph(+) ALL) is generally poor and reports from large studies are scarce. We evaluated the efficacy of allogeneic bone marrow transplantation (allo-BMT) for children with this type of leukemia. PROCEDURE: The chemotherapy regimens consisted of an induction phase and very intensive consolidation followed by a reinduction phase and late intensification treatment. The selection of treatment modalities such as chemotherapy, allo-BMT, or autologous transplantation was made by each institute. The principal endpoint was the outcome of children with Ph(+) ALL according to the treatment options. RESULTS: Thirty-two patients (4.3%) were diagnosed as Ph(+) ALL out of the 741 cases of ALL consecutively enrolled in two protocols of the Tokyo Children's Cancer Study Group (TCCSG) from 1989 to 1994. Thirty patients (93.8%) were induced into complete remission (CR). Of these 30 patients, eight children electively received allo-BMT in the first CR. Six of these patients are in continuous remission at a median follow-up of 58 (range 48-105) months after the diagnosis. One patient died following recurrence and another patient died of graft vs. host disease. Three patients treated with autologous BMT or peripheral blood stem cell transplantation in the first CR experienced a subsequent relapse. In the remaining 19 patients, 13 patients were treated with very high-risk chemotherapy alone and all relapsed within 28 months. One patient was excluded from the analysis because he was treated with standard-risk chemotherapy until relapse. The other five patients were also excluded from the analysis because Philadelphia chromosome was not detected until they relapsed. None of the relapsed patients survived in spite of treatment including allo-BMT. In multivariate analysis, only allo-BMT remained as an independent factor for good prognosis. CONCLUSIONS: The only way to cure children with Ph(+) ALL was allo-BMT in this study and its outcome seemed promising.

Adolescent↗
PubMed2001

Injection of CD4(+) and CD8(+) cells with donor or host accessory cells induces acute graft-vs-host disease in human skin in immunodeficient mice.

OBJECTIVE: We examined cell subsets with respect to cutaneous graft-vs-host disease by cell sorting selection of subsets of human mononuclear cells and injecting the subsets subcutaneously in a mouse model. MATERIALS AND METHODS: Cell suspensions containing cultured human epidermal cells and dermal fibroblasts from a single donor mixed with lymphoid cell subsets positively selected using the FACSVantage cell sorting instrument and/or MACS cell isolation kits from unrelated individuals were injected into immunodeficient mice. This model is known to generate human skin with histologic findings similar to human graft-vs-host disease. RESULTS: Donor T-cell subsets CD4(+) and CD8(+) plus either host or donor CD14(+) cells were necessary to cause acute cutaneous graft-vs-host disease. Although graft-vs-host disease can result from recognition of class I antigens expressed on human cutaneous cells by donor peripheral blood mononuclear cells, additional recognition of class II antigens expressed on host mononuclear cells resulted in more severe histologic manifestations. Dendritic cells that differentiated from donor and host monocytes also showed competent accessory cell function in this system. CONCLUSIONS: Based on this model, human cutaneous graft-vs-host disease was caused by donor CD4(+) cells and CD8(+) cells activated through recognition of host antigens, including class I and class II antigens presented by either donor or host CD14(+) cells or dendritic cells.

Animals↗
PubMed2001

Automatic discriminative sensitivity inside temporal window of sensory memory as a function of time.

Neural representation of preceding sound-patterns stored in the human brain, as reflected by mismatch negativity (MMN) related to the automatic discriminative process, is restricted to a duration of 160-170 ms due to the short form of auditory sensory memory termed the temporal window of integration (TWI). To examine the temporal uniformity of deviation-sensitivity inside TWI of sensory memory, magnetic MMN (MMNm) responses were measured with a dual 37-channel magnetometer for complex sounds of 170 ms duration containing an omitted (silent) segment. Frequent standard stimuli (probability of 80%) consisted of five tone segments. Deviant stimuli were different from standard stimuli in that one of four segments was occasionally (probability of 5%) omitted and replaced by a silent segment. The stimulus duration of 170 ms was intended to correspond to the postulated duration of TWI. When the silent segment occurred later in deviant stimulus, the MMNm peak amplitude was attenuated and MMNm peak latency, measured from the onset of each silent segment, was delayed. Thus, automatic deviation-detection sensitivity declines nonlinearly toward the end of TWI in auditory sensory memory. In the second experiment, two types of deviant stimuli, which differed from each other only in the period after the occurrence of the silent segment, elicited MMNm with the same peak latency but with a different peak amplitude. Thus, mismatch process is triggered at the moment of change but still lasts after the detection of deviation. In other words, both standard and deviant stimuli are treated as a unitary event within a TWI.

Acoustic Stimulation↗
PubMed2001

Successful hyperbaric oxygen treatment of life-threatening hemorrhagic cystitis after allogeneic bone marrow transplantation.

Hemorrhagic cystitis (HC) is a major cause of morbidity after allogeneic bone marrow transplantation (BMT). Many therapies have been investigated to prevent or treat HC, but effective treatment for HC is still limited. While the efficacy of hyperbaric oxygen therapy has been established for HC due to chemotherapy and/or radiation therapy, its role in HC occurring after allogeneic BMT has yet to be defined. We report two cases of life-threatening late-onset HC after allogeneic BMT in children, which resolved after treatment with hyperbaric oxygen.

Bone Marrow Transplantation↗
PubMed2001

Absence of a CD34- hematopoietic precursor population in recipients of CD34+ stem cell transplantation.

The purified CD34(+) cell fraction has been used for hematopoietic stem cell transplantation since they were demonstrated to have long-term reconstituting ability. Therefore, the potential effects of CD34(-) stem cells on the clinical course have been a major concern in recipients of CD34(+)-selected transplantation. To address this concern, we used an in vitro assay to determine whether transplant recipients have CD34(-)precursor population. Lin(-)CD34(-) cells were isolated from bone marrow cells in 11 transplant recipients including four CD34-selected transplantations, six standard bone marrow transplantations, and one T cell-depleted marrow transplantation. The frequency of the Lin(-)CD34(-) population in four CD34-enriched transplantation recipients was not different from those of normal donors or recipients of other modes of transplantation: 0.96 +/- 1.01% (mean +/- s.d., n = 4), 0.45 +/- 0.16% (n = 6), and 0.66 +/- 0.59% (n = 7), respectively. However, the Lin(-)CD34(-)population obtained from the recipients of CD34-enriched transplantation acquired neither CD34 expression nor colony-forming activity after 7 days of culture, whereas the cells from all the normal individuals and standard BMT recipients were able to differentiate into CD34(+) cells accompanied by the emergence of colony-forming activity.We conclude that recipients of CD34-enriched transplantation appear to have defects in their CD34(-) precursor population. The clinical significance of these defects will be determined in a life-long follow-up of these patients.

Adolescent↗
PubMed2001

Intramuscular spindle cell lipoma: Case report and review of the literature.

Spindle cell lipoma (SCL) is a relatively rare adipocytic neoplasm and is histologically characterized by a mixture of uniform spindle cells and mature fat cells. It occurs predominantly in male patients aged 45-65 years, and in most cases it arises in the subcutaneous tissue of the neck or shoulder. Although the neoplasm sometimes affects unusual sites, only three cases have been reported in which the lesion was intramuscular. Here we present a case of SCL arising in skeletal muscle; to our knowledge, the first report in 10 years. The tumor occurred in the neck of a 50-year-old male patient. Magnetic resonance imaging (MRI) revealed a lipomatous tumor within the right trapezius muscle. The tumor was localized beneath the fascia and was excised completely at surgery. Histologically, the tumor was typical of a spindle cell lipoma with no evidence of malignancy. An immunohistochemical study revealed all spindle cells were strongly positive for CD34. Differential diagnosis is discussed with a review of the literature.

Antigens, CD34↗
PubMed2001

Donor leukocyte infusion for Japanese patients with relapsed leukemia after allogeneic bone marrow transplantation: indications and dose escalation.

To clarify the role of dose escalation of donor leukocyte infusion (DLI) in the treatment of relapsed leukemia after allogeneic bone marrow transplant (BMT), data from 100 patients were collected from 46 facilities in Japan and analyzed with respect to indications and infused cell dose. Complete remission (CR) was achieved in 11 of 12 (91%) patients with relapsed chronic myelogenous leukemia (CML) in the chronic phase, 3 of 11 (27%) with CML in the acute phase, 8 of 21 (38%) with acute myelogenous leukemia (AML), 6 of 23 (25%) with acute lymphoblastic leukemia (ALL), and 5 of 11 (45%) with myelodysplastic syndrome (MDS). The probability of remaining in CR at 3 years was 82% in CML patients in the chronic phase, but 0% in those with CML in the acute phase, 7% in those with AML, 0% with ALL, and 33% with MDS. Acute graft-versus-host disease (GVHD) (> or = 2) developed in 31 of 89 (34%) patients with human leukocyte antigen identical related donors and was fatal for 7 (7%). A leukocyte dose of 1 x 10(7)/kg of recipient body weight with CML in the chronic phase, 3 x 10(7)/kg of recipient body weight with MDS, and 1 x 10(8)/kg of recipient body weight with acute leukemia appeared to be optimal as an initial dose of DLI. However, the minimal dose of leukocyte developing fatal GVHD was 7 x 10(7)/kg of recipient body weight. These suggest that a relatively small dose of DLI ranging from 1 x 10(7)/kg to 5 x 10(7)/kg of recipient body weight should be administered initially then the infused escalating dose 2 or 3 months later in patients with CML in the chronic phase and MDS. However, a large number of leukocytes around 1 x 10(8)/kg are needed to induce graft versus leukemia effects in patients with acute leukemia despite a 7% fatality in GVHD.

Adolescent↗
PubMed2001

Extracellular matrix components in a case of retrocorneal membrane associated with syphilitic interstitial keratitis.

PURPOSE: A web-like retrocorneal membrane (RCM) is an uncommon complication of chronic syphilitic interstitial keratitis. Extracellular matrix components have not yet been defined in this structure, although previous histologic examinations have suggested the presence of collagen. We examined the presence and distribution of extracellular matrix components in a patient with an RCM. METHODS: A specimen of the opaque cornea affected by syphilitic interstitial keratitis with RCM formation was obtained during penetrating keratoplasty in a 62-year-old woman and was evaluated by histology, immunohistochemistry, and scanning electron microscopy (SEM). Antibodies against collagen types I, III, and IV; fibronectin; vimentin; alpha-smooth muscle actin (alpha-SMA); heat shock protein 47 (Hsp 47); proliferating cell nuclear antigen (PCNA); and Ki67 were used. RESULTS: Histologic analysis detected multiple concentric, acellular layers positive for collagen types I, III, and IV. The corneal endothelial cells (CECs) were positive for vimentin, collagen I, fibronectin, and Hsp 47 but not for alpha-SMA. Furthermore, the CECs were negative for PCNA and Ki67, indicating that they were not proliferating. SEM revealed the RCM was covered by CECs with a fibroblastic appearance. CONCLUSION: RCM associated with syphilitic interstitial keratitis contained collagen types I, III, and IV and fibroblast-like CECs. These CECs may secrete the extracellular matrix components found in the RCM. Hsp 47 up-regulation in the CECs may play an important role in RCM formation. These findings provide further insights into the phenotypic modulation of CECs.

Collagen↗
PubMed2001

Final height and growth hormone secretion after bone marrow transplantation in children.

Growth hormone (GH) deficiency has been regarded as a principal determinant for growth failure following bone marrow transplantation (BMT). We herein analyzed final height and GH secretion in the patients who received BMT during childhood. The study on final height in 30 patients (23 males; 19 with malignant disease) who underwent BMT before or at the onset of puberty showed the following findings: (1) Final height SD score (SDS) significantly decreased compared to pretreatment height SDS. (2) Patients who underwent BMT before the age of 10 years showed significantly greater reduction in height SDS compared to those who received after the age of 10 years. (3) The type of disease or a difference in preconditioning regimen did not influence the outcome of growth. (4) No patient showed GH deficiency. The study on GH secretion included 71 patients who had been followed for more than 5 years and who underwent insulin tolerance test more than twice following BMT. Thirteen patients experienced poor GH response at least once. Two of these patients had poor GH response repeatedly. In conclusion, children who undergo BMT at younger age have a higher risk of growth failure, and GH deficiency is not a major contributing factor for growth impairment following BMT.

Adolescent↗
PubMed2001

[A case of malignant melanoma occurring 63 years after evisceration].

BACKGROUND: We report a rare case of a 69-year-old woman with malignant melanoma of her right socket, who had undergone evisceration of her right globe for unknown reasons at the age of 6. CASE: A 69-year-old woman presented with the complaint of inability to keep the prosthesis in her socket. A large blackish brown mass was seen behind the eyelids, and biopsy of this tissue revealed a mixed type malignant melanoma. A right exenteration was performed and histopathologic examination demonstrated a large tumor mass anterior and adjacent to the remains of the eviscerated globe. CONCLUSION: During evisceration, uveal pigment may be incompletely removed from the globe, or may be inadvertently scattered in the orbit. This case may demonstrate the development of a malignant melanoma from the uvea of an eviscerated globe. We recommend that careful long-term follow-up be performed on patients who have undergone evisceration.

Aged↗
PubMed2001

Evaluation of the AMPLICOR CMV, COBAS AMPLICOR CMV monitor and antigenemia assay for cytomegalovirus disease.

The AMPLICOR CMV (qualitative DNA assay by PCR), COBAS AMPLICOR CMV Monitor (quantitative DNA assay by PCR), and antigenemia assay were tested for their ability to diagnose cytomegalovirus (CMV) infection in 115 immunocompromised patients. The AMPLICOR qualitative assay and the antigenemia assay were positive for all nine patients with a clinical diagnosis of CMV disease. The AMPLICOR quantitative assay was negative for one of the nine patients. In 106 patients without CMV disease, the AMPLICOR qualitative test was positive in 22, the quantitative test was positive in 23, and the antigenemia test was positive in 55 patients. The AMPLICOR qualitative and quantitative assays had specificities of 79% and 78% in patients without CMV disease, while that of the antigenemia assay was 48%. Diagnostic efficiencies were 79% for the AMPLICOR qualitative assay, 69% for the AMPLICOR quantitative assay, and 48% for the antigenemia assay. All three tests yielded positive results before, or at the same time as, the onset of CMV disease in most cases, which suggests they can be used to predict disease before the onset of symptoms. During antiviral treatment, test results tended to decrease quantitatively and finally became negative; negative results were followed by remission of symptoms. This suggests that the AMPLICOR quantitative assay and the antigenemia assay could be useful for monitoring therapeutic efficacy. The AMPLICOR qualitative and quantitative assays, as well as the antigenemia assay were considered effective for all of the following: diagnosing CMV disease, predicting the onset of disease, and evaluating the effectiveness of antiviral chemotherapy. The antigenemia assay was at times difficult to perform in the case of severely neutropenic patients, whereas the AMPLICOR assays could be used in such cases.

Antigens, Viral↗
PubMed2001

[A patient of chronic graft-versus-host disease presenting simultaneously with polymyositis and myasthenia gravis].

We report a patient of polymyositis and myasthenia gravis as manifestations of chronic graft-versus-hot disease (GVHD). A 48-year-old man was diagnosed as having chronic myelogenous leukemia at the age of 42 years, and had bone marrow transplantation (BMT) two years after the onset of the disease. Since he suffered from mild liver dysfunction and cutaneous involvement manifesting chronic GVHD, he was placed on prednisolone and cyclophosphamide. As his condition improved, the prednisolone was gradually tapered. Forty-one months after the BMT, the patient developed muscle pain and muscle weakness. A diagnosis of polymyositis was made from muscle biopsy and laboratory findings. An increase in the prednisolone dose was effective but a few weeks later the patient noticed ptosis and recurrence of muscle weakness. A tensilon test and anti-acetylcholine receptor antibody produced positive results, leading to a diagnosis of myasthenia gravis. Only one case of polymyositis and myasthenia gravis as manifestations of chronic GVHD has been reported, and in our patient both symptoms appeared almost at the same time. Although neuromuscular symptoms as a manifestation of chronic GVHD are rare, all patients receiving BMT should be carefully followed up neurologically to detect neuromuscular complications.

Bone Marrow Transplantation↗
PubMed2000

The effect of deviant stimulus probability on the human mismatch process.

The present study addresses the separate activities of frontal and temporal MMN generators which might be differentially affected by a change in the probability of standard stimuli. As the probability of standard stimuli was increased, the frontal MMN component significantly increased in amplitude, while the temporal one was not affected. Correspondingly, the scalp current density (SCD) maps showed that the temporal MMN generator was activated even at low probability of standard stimuli, suggesting that even the weak memory trace could start the automatic mismatch process, whereas the frontal MMN generator was activated only with increased probabilities of standard stimuli, suggesting that the stronger the memory trace is, the easier it might trigger the involuntary switching of attention to stimulus change.

Acoustic Stimulation↗
PubMed2000

The masking effect in foreign speech sounds perception revealed by neuromagnetic responses.

The backward masking effect on non-native consonants by a following vowel was examined using neuromagnetic responses to synthesized speech sounds. Native speakers of Japanese were presented with sequences of frequent (85%) and infrequent (15%) speech sounds (/ra/ and /la/ respectively, no /l/ /r/ contrast in Japanese language). The duration of the stimuli was 110 ms in a short session and 150 ms in a long session. In the short session, the stimuli were terminated in the course of the transition from the consonant to the vowel to diminish the masking effect from the vowel part. A distinct magnetic counterpart of mismatch negativity (MMNm) was observed for the short session, whereas a smaller MMNm was observed for the long session.

Adult↗
PubMed2000

Immunosuppressive therapy using antithymocyte globulin, cyclosporine, and danazol with or without human granulocyte colony-stimulating factor in children with acquired aplastic anemia.

A prospective multicenter trial of 119 children 1 to 18 years of age with newly diagnosed aplastic anemia (AA) was conducted, comparing treatment using antithymocyte globulin (ATG), cyclosporine (CyA), and danazol (DAN) with or without rhG-CSF (400 microg/m(2), day on days 1-90). All children with very severe AA received rhG-CSF (VSAA group, n = 50). The other children were randomized to receive ATG, CyA, DAN, and rhG-CSF (G-CSF+ group, n = 35) or ATG, CyA, and DAN without rhG-CSF (G-CSF- group, n = 34). After 6 months, the hematologic response rate was 71%, 55%, and 77% in the VSAA group, G-CSF+ group, and G-CSF- group, respectively. There was no difference in the incidence of febrile episodes and documented infections between the G-CSF+ and G-CSF- groups. Bone marrow transplantation (BMT) was attempted in 22 patients in whom initial immunosuppressive therapy (IST; n = 18) failed or in whom a relapse occurred after an initial response (n = 4). Nineteen of the 22 patients are alive and well after a median follow-up of 18 months (range, 3 to 66 months) since BMT. The probability of survival at 4 years was 83% +/- 7% in the VSAA group, 91% +/- 5% in the G-CSF+ group, and 93% +/- 6% in the G-CSF- group. Myelodysplastic syndrome (MDS)/acute myeloid leukemia (AML) developed in one patient in each of the three groups; the overall risk for MDS/AML was 3% +/- 2% at 4 years. Because the results of IST were encouraging, it is suggested that children with AA receive IST as first-line therapy if there is no human leukocyte antigen-matched sibling donor.

Adolescent↗
PubMed2000

Automatic auditory information processing in sleep.

STUDY OBJECTIVES: The mismatch negativity (MMN) component of the event-related potentials reflects the automatic detection of sound change. Only a few researchers have investigated the MMN elicitation during sleep in adult human and some of them reported that MMN amplitude was decreased in sleep compared to in waking. However, it is not clear that the decrease of MMN amplitude was due to increased drowsiness or long-term response decrement. Two experiments were conducted to clarify whether or not the MMN was elicited in each sleep stage. We presented auditory stimuli to subjects continuously from waking until sleep state (Experiment 1). Using the same experimental condition, we examined whether or not MMN amplitude was influenced by long-term stimulus presentation (80min.) and by vigilance level (Experiment 2). DESIGN: N/A SETTING: N/A PARTICIPANTS: N/A INTERVENTIONS: N/A MEASUREMENTS & RESULTS: Experiment 1: MMN was obtained in both drowsiness and REM sleep. MMN was significantly smaller in amplitude and shorter in latency in the both stages than in the waking state. However, MMN was not found in another sleep stage. Experiment 2: Amplitudes were no different among 0-20 min., 20-40 min., 60-80 min. But it was decreased in 40-60 min. and power value of alpha-wave was decreased in 40-60 min. CONCLUSIONS: To obtain the reliable data, by using the automatic spectral analysis, we confirmed that MMN was elicited in REM sleep. MMN was not influenced by long-term stimulation. The result suggested that auditory stimuli could be processed in the pre-attentive sensory memory even in REM sleep.

Adult↗