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H Hirabayashi

Publications and source records attributed to H Hirabayashi.

At least 73 records · Page 4Linked to original sources
PubMed1994

Experimental study of the mechanism of seizure induction: changes in the concentrations of excitatory amino acids in the epileptic focus of the cat amygdaloid kindling model.

L-glutamate (Glu) and L-aspartate (Asp) are two major excitatory amino acids that may be involved in seizure susceptibility and seizure induction. The concentrations of Glu and Asp were measured by microdialysis in the epileptic focus in a cat amygdaloid kindling model. Sequential changes in Glu and Asp (before, during, and after seizure) were measured in the partial seizure (S4) and generalized seizure (S6) groups. By stimulation at and 50 microA below the partial seizure-triggering threshold in the S4 group and the generalized seizure-triggering threshold in the S6 group, Glu was released from the epileptic focus in the S4 group, and both Glu and Asp were released in the S6 group after seizure and stimulation (below threshold), and the amount of Glu and/or Asp release determined seizure induction. Excitatory amino acids may be the trigger of seizure induction in the cat amygdaloid kindling model.

Amygdala↗
PubMed1994

Pleomorphic adenoma of the lacrimal gland manifesting as exophthalmos in adolescence--case report.

A 16-year-old girl presented with a pleomorphic adenoma of the lacrimal gland manifesting as left painless exophthalmos which had persisted for 3 years. Computed tomography revealed a tumor about 15 mm in diameter in the superolateral site of the left orbit. The tumor was removed completely by combined orbitofrontal craniotomy through a transcranial approach. Histological examination demonstrated the growth of tumor cells as glandular cavities or sheets, with myxoid and partly chondroid connective tissue stroma. Pleomorphic adenoma of the lacrimal gland is unusual in adolescents.

Adenoma, Pleomorphic↗
PubMed1994

[Lung resection for lung carcinoma with idiopathic interstitial pneumonia].

Of 12 patients who underwent lung resections for lung cancer with idiopathic interstitial pneumonia (IIP), eight patients survived and four patients died due to acute exacerbation of IIP after the operation. The preoperative values for percent forced vital capacity, predicted postoperative percent vital capacity, percent one-second forced expiratory volume index and serum level of C-reactive protein were significantly different between the group of patients who survived and that of having died. Three days after the operation, the percentage of lymphocytes among leukocytes and serum level of lactate dehydrogenase in the two groups were both significantly different. These findings showed that the operative strategy for patients with lung cancer and IIP needs specifically careful consideration for operative procedure, and preoperative serum levels of C-reactive protein and postoperative lactate dehydrogenase and the percentage of lymphocytes in leukocytes would be useful in evaluation of the severity of IIP.

Adenocarcinoma↗
PubMed1994

[Malignant parasagittal meningioma appearing as a large subcutaneous mass].

We present a rare case of malignant meningioma appearing as an extracranial soft-tissue mass. A 34-year-old male was admitted with left parietal subcutaneous soft-tissue mass. Neurological examination on admission revealed right leg monoparesis and papilledema. Skull X rays showed hyperostosis of the left parietal bone. There was no evidence of bony destruction. CT and MRI showed a tumor with a large intracranial component, which was homogeneously enhanced. The tumor was totally removed by left ostoplastic craniotomy. The light-microscopic examination showed a meningothelial meningioma accompanied by malignant components with necrotic foci and mitotic figures. Tumor cells had invaded all the layers of the skull via the Haversian canals. We propose that hyperostosis with tumor invasion through all three layers of the skull should be considered as a malignant feature.

Adult↗
PubMed1993

Evidence for local and systemic activation of immune cells by peritumoral injections of interleukin 2 in patients with advanced squamous cell carcinoma of the head and neck.

Interleukin 2 (IL2) was injected peritumorally and intranodally in 36 patients with unresectable squamous cell carcinoma of the head and neck enrolled in an Eastern Cooperative Oncology Group-sponsored phase Ib trial (EST P-Z388). Groups of 6 patients received escalating doses(200, 2 x 10(3), 2 x 10(4), 2 x 10(5), 2 x 10(6), and 4 x 10(6) units) of IL2 daily 5 times/week for 2 weeks. Tumor biopsies were obtained before and after IL2 therapy. Tumor tissue was provided for histology, and the remaining fresh tissue was divided for snap-freezing in -75 degrees C and for separation of tumor-infiltrating lymphocytes (TIL) and tumor cells. Immunophenotyping of TIL performed on cryostat sections of paired pre- and post-IL2 biopsy tissues showed increases after IL2 therapy in the number of T-cells (P = 0.005), natural killer (NK; CD16+) cells (P = 0.0001), CD25+ cells (P = 0.004), and HLA-DR+ cells (P = 0.001) accumulating in the tumor stroma. In the tumor parenchyma, NK cells (P = 0.0001) and HLA-DR+ cells (P = 0.003) were increased after IL2 therapy. The T:NK cell ratios in the tumor stroma and parenchyma were decreased after therapy, suggesting selective accumulation of NK cells. By flow cytometry, TIL recovered from post-IL2 biopsy tissues were enriched (P < 0.05) in CD3-CD56+ (NK) cells. In situ hybridization with [35S] cDNA probes for cytokines and IL2 receptors indicated that the numbers of cells expressing mRNA for IL2, tumor necrosis factor alpha, IL1-beta, gamma-interferon, transforming growth factor beta, and IL2 receptor p55 or p70 were increased in post-IL2 biopsy tissues as compared to pre-IL2 tissues. Cytolytic activity of TIL isolated from post-IL2 tissues was also increased, as determined in 4-h 51Cr release assays against K562 targets (12 +/- 3 mean lytic units/10(7) cells +/- SEM pre-IL2 versus 46 +/- 13 post-IL2; n = 16) and against autologous tumor (13 +/- 8 versus 68 +/- 26; n = 9). Fresh TIL of one clinical responder showed relatively high levels (195 lytic units) of autotumor cytotoxicity after IL2 therapy versus no activity prior to therapy. In the blood, NK and lymphokine-activated killer cell activity, and percentages of CD3-CD56+ NK cells and of activated (CD25+) T-lymphocytes were increased for all doses of IL2.(ABSTRACT TRUNCATED AT 400 WORDS)

Carcinoma, Squamous Cell↗
PubMed1993

Human cytotoxic T-cell lines with restricted specificity for squamous cell carcinoma of the head and neck.

Human cytotoxic T-lymphocyte (CTL) lines with specificity restricted for autologous squamous cell carcinoma of the head and neck (SCCHN) were established from peripheral blood lymphocytes obtained at the time of surgery and again at two different times after surgery from a patient with cancer of the tongue. The CTL lines were cultured in the presence of interleukin (IL) 2, IL4, and autologous tumor (AuTu) cell monolayers. All three lines were CD3+CD8+CD11b-HLA-DR+ T-cell receptor alpha/beta+. They were tested in 4-h51Cr release assays against SCCHN cell lines (n = 5) and a variety of nonsquamous human tumor (n = 5) and normal (n = 5) cell targets and was found to lyse only AuTu (PCI-50) and three allogenic SCCHN cell lines. Lysis of AuTu and the three allogenic SCCHN targets by the established CTL lines appeared to be major histocompatibility complex class I restricted, since it was blocked by monoclonal antibodies to class I histocompatibility complex antigens. The CTL lines proliferated in vitro in response to autologous PCI-50 or an allogenic SCCHN cell line (PCI-1). The lines have been maintained in culture in the presence of AuTu monolayers and retained cytotoxicity against AuTu for over 20 weeks. The AuTu (PCI-50) cell line was tested for in vitro sensitivity to cytotoxic or cytostatic effects of various effector cells, including the CTL lines. PCI-50 targets were resistant to lysis by resting human mononuclear cells but sensitive to IL2-activated natural killer cells in 4-h 51Cr release assays. In comparison with IL2-activated natural killer cells, the CTL line mediated lower levels of lysis against AuTu. Growth of PCI-50 cells in culture was significantly inhibited by a combination of gamma-interferon and IL2 or by high concentrations of tumor necrosis factor alpha. While supernants of IL2-activated natural killer cells were growth inhibitory, those of the CTL line were not. On the other hand, lysis of AuTu targets by the CTL line was increased by preincubation of the tumor cells with tumor necrosis factor alpha or gamma-interferon. These cytokines augmented expression of HLA-class I, HLA-class II, and intercellular adhesion molecule I, but not squamous cell carcinoma-associated antigens, E7 and A9, on PCI-50 cells. The CTL lines described are the first with restricted specificity for autologous SCCHN ever reported and their availability will facilitate studies of the AuTu T-cell response in head and neck cancer.

Aged↗
PubMed1993

Myelodysplastic syndrome with eosinophilia in bone marrow. Gunma Haematology Study Group.

Clinical features were investigated in 114 patients with de novo myelodysplastic syndrome (MDS) diagnosed over the past 10 years, and eight cases (7%) were complicated with eosinophilia in the bone marrow. Two patients had refractory anaemia (RA), five had RA with excess of blasts (RAEB), and one had RAEB in transformation. Their bone marrow cells exhibited tri-lineage dysplasia and morphological abnormalities in eosinophils. Cytogenetics revealed major karyotype abnormalities (MAKA) in five patients. Survival durations were significantly shorter than those of other MDS patients. Our study suggests that marrow eosinophilia in MDS is strongly related to the coexistence of MAKA.

Aged↗
PubMed1993

Splenic lymphoma with villous lymphocytes with CD5+, CD11c+ B-cell phenotype.

A 64-year-old male suffered from splenomegaly without lymphadenopathy. His WBC count on admission was 6.1 x 10(9)/l with 55% abnormal lymphocytes. No monoclonal gammopathy was detected. Abnormal cells shown in films usually had relatively abundant cytoplasm with serrated edges. Under phase-contrast microscopy, the cells displayed short, needle-like processes. The immunophenotype of peripheral blood mononuclear cells were CD19+, CD20+, CD11c+, FMC7+, CD5+, CD10-, CD25- and SIg+. The spleen histology showed a distinctive pattern of white pulp infiltration by abnormal lymphocytes with features of plasma cell differentiation. These findings were compatible with the features of splenic lymphoma with villous lymphocytes.

Antigens, CD↗
PubMed1993

[Complete remission of acute promyelocytic leukemia accompanied by DIC in an elderly patient treated with all-trans retinoic acid].

In this paper we report on a 74-year-old female patient who was suffering from acute promyelocytic leukemia (APL) and who, upon admission to our hospital on February 20, 1992, was also found to be stricken with disseminated intravascular coagulation (DIC). The DIC, however, was quickly arrested by administration of heparin and there was no exacerbation. Also, on admission her peripheral blood leukocyte count was 700/ul, but after oral administration of all-trans retinoic acid (ATRA) (45 mg/m/day) was begun on February 22, this count gradually increased and peaked at 35,200/ul on March 7. Some of these matured leukocytes revealed dysplastic features; some had Auer bodies. At this time cytogenetic analysis of bone marrow cells showed 46XX, t (15;17). The leukocyte count gradually decreased to 1,500/ul, and the dysplastic features disappeared. On March 21 her thrombocytes and reticulocytes began to increase, and she achieved complete remission when her abnormal karyotype disappeared on March 24. She suffered no severe complications such as infection or hemorrhage during treatment. We therefore suggest that ATRA is very effective for APL in elderly patients. It neither exacerbates DIC nor increases the risk of infection. In fact, when ATRA treatment is compared to the standard cytotoxic chemotherapy there is a reduced risk of infection.

Administration, Oral↗
PubMed1992

[Epithelial cyst occurring on the anterior surface of the brain stem--case report and review of the literatures].

Epithelial cysts in the posterior fossa are very rare, and only 22 cases have been reported in literatures. We report a case of epithelial cyst occurring on the anterior surface of the brain stem. A 31-year-old man was admitted to our hospital complaining of right hemiparesis and dysarthria. Plain CT showed a heterogeneous (isodense-hyperdense) mass in front of the pons, and was not enhanced after injection of contrast medium. As for findings of MRI, the tumor revealed as heterogeneous (isointense-hyperintense) mass on T1-weighted image and also heterogeneous (hypointense-hyperintense) mass on T2-weighted image. We removed partially the tumor which content was like yogurt. The histological findings of the cyst wall revealed a pseudostratified columnar ciliated epithelium.

Adult↗
PubMed1992

[Changes in seizure-triggering threshold and after discharge duration in seizure susceptibility].

Epilepsy is analysed on terms of two different conditions, seizure susceptibility and seizure induction. Reports on detailed changes of seizure-triggering threshold and after discharge duration in seizure susceptibility are few. We examined staged changes of seizure-triggering threshold and after discharge duration in seizure susceptibility in a cat amygdaloid kindling model. Ten crossed adult cats were used. We investigated after discharge threshold (ADT), partial seizure threshold (PST) in stage 4 group (P) and generalized seizure threshold (GST) in stage 6 group (C). At the same time, we examined after discharge duration on electroencephalograph (EEG) in each stage. Seizure-triggering threshold decreases significantly step by step. After discharge duration increases significantly step by step. It is concluded that staged decrease of seizure-triggering threshold and increase of seizure's grade and duration was seen in seizure susceptibility.

Amygdala↗
PubMed1991

Extracapsular spread of squamous cell carcinoma in neck lymph nodes: prognostic factor of laryngeal cancer.

Fifty-two patients with laryngeal cancer who underwent radical neck dissections were studied to provide further information on the prognosis of various clinical and histopathological parameters. Extracapsular spread (ECS) was found in 31% of patients with N1 nodes, and in 60% of patients with histopathologically positive nodes. The 5-year survival rate of histopathological findings was as follows: patients with no pathological evidence of neck metastasis (81%), patients with neck metastasis confined to the lymph node (no ECS) (76%), and patients with ECS (17%). The difference in survival rate between patients with no ECS and patients with ECS was statistically significant (P = .001). Staging classification, T-stage classification, the number of malignant nodes, the diameter of malignant nodes, and combined therapy had no prognostic importance. The most significant factor was the presence of extracapsular spread.

Carcinoma, Squamous Cell↗
PubMed1991

[A comparative study of multimodality evoked potentials and computed tomography in head injuries].

Multimodality evoked potentials (EPs) or three types of EPs--auditory brainstem response (ABR), somatosensory evoked potential (SEP), and visual evoked potential (VEP)--were recorded in 51 cases of traumatic intracranial hemorrhage within 3 days after injury. In order to assess these EPs, five EP grades were constructed, from normal, Grade I, to highly abnormal, Grade V. Furthermore, an EP pattern classification was devised to integrate the respective EP grades. Namely, PA, consisting of all three EPs within Grades I-III; PB, composed of one type of EP or both ABR and VEP at Grades IV and V; PC, consisting of both SEP and VEP at Grades IV and V; PD, comprising both ABR and SEP at Grades IV and V; and PE, covering all three EPs at Grades IV and V. PA signifies "no severe damage," PB, "localized damage," PC, "severe cerebral damage," PD, "severe brainstem damage," and PE, "severe diffuse damage." The results when compared with computed tomography (CT) findings were as follows: 1) The size of hematoma correlated with the SEP grade in 16 cases of acute epidural hematoma; a hematoma diameter of 17.5 mm was the threshold value at which SEP abnormalities developed. Eleven patients who underwent surgical removal of the hematoma showed "no severe damage," and the outcome was good. 2) In 13 cases of acute subdural hematoma, six cases revealed "severe cerebral damage" or "severe diffuse damage." In such cases, the degree of damage was not related to the hematoma size, and the outcome was very poor. 3) In 13 cases of a solitary contusional hemorrhage, only one case revealed "severe diffuse damage" and subsequently died.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[Sequential changes in content of excitatory amino acids in the epileptic focus during seizure].

Recently much attention has been paid to excitatory amino acids in seizure susceptibility and induction. In order to examine the relationship between epilepsy, especially seizure induction, and excitatory amino acids, we examined sequential change in content of excitatory amino acids in the epileptic focus by microdialysis system in a cat amygdaloid kindling model. Fifteen crossbred adult cats divided into three groups: a sham operation group (Sh) as the control, just after stage 4 group (S4), and just after stage 6 seizure group (S6). Under halothane anesthesia, Microdialysis probe was inserted to the kindled focus, the right amygdala, and glutamate and aspartate contents of extracellular fluid were measured from 15 minutes prior to 30 minutes after seizure by high performance liquid chromatography (HPLC). The probe was perfused with artificial cerebrospinal fluid at a flow rate of 2 microliters/min for 5 minutes. Before seizure, glutamate and aspartate concentration showed no significant changes in the S4 and S6 group compared with the Sh group. But after seizure, glutamate concentration was significantly higher in the S4 and S6 group temporally, while aspartate concentration was higher only in the S6 group temporally. Based on the results that the release of glutamate and aspartate do not change in seizure susceptibility, that glutamate is released in partial seizure, and that glutamate and aspartate are released in generalized seizure from the epileptic focus, excitatory amino acids are involved in seizure induction in a cat amygdaloid kindling.

Amino Acids↗
PubMed1991

[Patients resuscitated from cardiopulmonary arrest: clinical and electrophysiologic study].

Clinical and electrophysiologic studies (EPS) were carried out in 12 patients who were resuscitated from cardiopulmonary arrest (CPA). They were 8 males and 4 females, ranging from 33 to 73 years of age with a mean of 55 years. Underlying diseases included old myocardial infarction (OMI) with aneurysm (An) in 6 patients, variant angina, arrhythmogenic right ventricular dysplasia, Romano-Ward syndrome, complete atrioventricular block in one each, and diseases of unknown etiology in 2. Ergonovine-provocative coronary angiography (CAG) was performed in 3 patients, and EPS including ventricular tachycardia study was performed in 7. Coronary artery spasm was induced in one patient during CAG; sustained monomorphic ventricular tachycardia in 4 patients; and repetitive ventricular response in 2 of 7 patients examined by EPS. The causes of cardiopulmonary arrest were clearly demonstrated by the above-described examinations in 3 cases of clinically unidentified etiology. Drug therapy was performed in 6 patients during EPS (1.7 drugs/case), which was effective in one, ineffective in 3, and undetermined in 2. Of 2 patients whose surgical treatment was unsuccessful, atrial pacing with propranolol administration was used in a patient with Romano-Ward syndrome. The remaining patients were followed up medically. Cardiopulmonary arrest recurred in 3 patients and resuscitation was not successful in any of them; one with OMI and the other 2 with idiopathic ventricular fibrillation who refused EPS and died suddenly 10 months and 12 months after their initial resuscitation. Cardiac arrest did not recur in any of those who underwent complete examinations and were treated with medications, however, it recurred in 3 of 5 patients without complete medications. As a whole, cardiopulmonary arrest recurred in 3 of 12 patients (25%) within one year after the onset of symptoms. To reduce the possibility of the recurrence of arrest and improve prognosis in patients with previous successful cardiac resuscitation, intensive examinations for the causes, therapy including EPS and ergonovine CAG, full medications and surgical treatment may be helpful.

Adult↗