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Biomedical subjects

Y Kuriyama

Publications and source records attributed to Y Kuriyama.

At least 37 records · Page 2Linked to original sources

[Possible role of immunocompetent cells on periodic exacerbation of idiopathic thrombocytopenic purpura].

A 44 year-old man was admitted to our hospital in October, 1992 with epistaxis. Fifteen months before admission, thrombocytopenia had been pointed out, but he had no bleeding episode. At admission, neither hepatosplenomegaly nor lymph node swelling was observed. Hematological findings were as follows; WBC 10,000/microliter, Hb 14.0 g/dl, PLT 5,000/microliter, including giant platelets. Platelet associated IgG (PAIgG) was 471 ng/10(7) cells. Bone marrow aspiration revealed normocellularity with moderate increase in the number of mature megakaryocytes, but no dysplastic changes were seen. Biochemical and radiological examinations disclosed neither malignant diseases nor autoimmune diseases. Based on the diagnosis of idiopathic thrombocytopenic purpura, danazol therapy (300 mg/day) was started in November, 1992. After initiation of treatment, the platelet count changed cyclically every 4 weeks. To elecuidate the mechanism of this phenomenon, we periodically evaluated the patient's immunological background. T lymphocyte counts and subset proportions remained almost the same through out the course, whereas NK cell counts and NK activity coincided with the change of the platelet count. These results suggest that in this case NK cells may play a role in the cyclic fluctuation of platelet count by regulating the immune system.

Adult↗

Near-hexaploid Ph-positive acute myeloid leukemia with major-BCR/ABL transcript.

We describe the first case of acute myeloid leukemia (AML) with a Philadelphia (Ph) translocation and a near-hexaploid range chromosome number, whose leukemic cells had the major-BCR/ABL transcript. The genesis of near-hexaploid leukemic cells might be due to endoreduplication of triploid leukemic cells with the Ph, since the relapsed leukemic cells had triploid range chromosomes with double Ph chromosomes.

Aneuploidy↗

[A lower-leg ulcer during hydroxyurea therapy for essential thrombocythemia].

A skin ulcer of the lateral malleous developed in a 61-year-old man receiving hydroxyurea for essential thrombocythemia. In the past, skin ulcers have been reported in patients with chronic myeloproliferative diseases, including essential thrombocythemia, who had been treated with hydroxyurea. In the current case, vasculitis or thrombi in vessels of the biopsied specimen of the lower leg were not observed, and the patient required skin-graft operation. Accordingly, we concluded that the skin ulcer might be due to the administration of hydroxyurea. Thus, the dose of hydroxyurea was decreased.

Foot Ulcer↗

[High activity of antistreptolysin-O in a case of IgM myeloma].

A 56-year-old man was admitted to our hospital in November, 1991 because of hyperproteinemia and anemia. Total protein showed 12 g/dl and serum immunoglobulins were as follows; IgG 974 mg/dl, IgA 142 mg/dl, IgM 9270 mg/dl. M-component was identified as IgM-kappa with immunoelectrophoresis and serum viscosity indicated 6.9. Although the patient had no history of severe streptococcal infection, his serum showed very high activity of ASLO (6890 IU/ml). Bence Jones protein was detected in the urine and determined to be of kappa-type. Plasma cells occupied 43% of bone marrow nucleated cells and their cytoplasms were stained with FITC-labeled anti-IgM and anti-kappa antibodies. X-ray examination disclosed punched out lesions in the skull. Consequently, the patient was diagnosed as having IgM-myeloma. At first, VCAP regimens were given after plasmapheresis, but had no effect. Therefore, the patient was treated with CHOP protocol and the serum IgM decreased in amount and the proportion of bone marrow myeloma cells got down to 17%. ASLO titer also decreased in parallel with IgM. These findings suggest that IgM in this case had ASLO activity.

Antistreptolysin↗

[Lymphocyte subsets in bronchoalveolar lavage fluid from patients with idiopathic interstitial pneumonia].

Lymphocyte activation may be involved in interstitial inflammatory processes in the lungs. We analyzed lymphocytes in bronchoalveolar lavage fluid obtained from 15 patients with idiopathic interstitial pneumonia (IIP) and from 7 controls. Clinical criterial were used to divide the patients with IIP into two groups: acute (n = 5) and chronic (n = 10). Lymphocytes in the bronchoalveolar lavage fluid were analyzed with a flow-cytometric two-color system. Differential cell counts showed that percentages and numbers of lymphocytes were significantly higher in patients with acute IIP (44.2 +/- 25.2%, 12.3 +/- 8.18 x 10(4)/ml) than in controls (8.31 +/- 3.66%, 0.69 +/- 0.39 x 10(4)/ml, p < 0.05) and in patients with chronic IIP (8.44 +/- 6.11%, 1.58 +/- 1.08 x 10(4)/ml, p < 0.05). In particular, percentages and numbers of CD8+ S6F1+ lymphocytes, which are regarded as activated cytotoxic T lymphocytes were markedly higher in patients with acute IIP (32.3 +/- 16.0%, 39.6 +/- 37.1 x 10(3)/ml), than in controls (6.31 +/- 1.69%, 0.42 +/- 0.25 x 10(3)/ml, p < 0.05) and in patients with chronic IIP (10.6 +/- 6.16%, 1.88 +/- 1.42 x 10(3)/ml, p < 0.05). These data suggest that patients with acute IIP differ from those with chronic IIP in the percentage and the number of lymphocytes in bronchoalveolar lavage fluid, and that activated cytotoxic T lymphocytes may play an important role in the pathogenesis of acute IIP.

Acute Disease↗

[Subsets of lymphocytes in bronchoalveolar-lavage fluid from patients with idiopathic bronchiolitis obliterans organizing pneumonia].

Lymphocyte activation may be involved in interstitial inflammatory processes in the lungs. We analyzed lymphocytes in bronchoalveolar lavage fluid obtained from 5 patients with idiopathic bronchiolitis obliterans organizing pneumonia and from 7 control subjects. Lymphocytes were analyzed by two-flow cytometry. Differential cell counts showed that the percentage and the number of lymphocytes was higher in the patients (32.9 +/- 21.9%, 12.8 +/- 8.32 x 10(4) cells/ml) than in the controls (8.31 +/- 3.66%, 0.69 +/- 0.39 x 10(4) cells/ml, p < 0.05). In particular, the patients had many more CD8+ S6F1+ lymphocytes (which are considered to be activated cytotoxic T lymphocytes; 32.2 +/- 11.8%, 42.0 +/- 26.5 x 10(3) cells/ml) than did the controls (6.31 +/- 1.69%, 0.42 +/- 0.25 x 10(3) cells/ml, p < 0.01). These data indicate that activated cytotoxic T lymphocytes may be important in the pathogenesis of bronchiolitis obliterans organizing preumonia.

Aged↗

Analysis of bone marrow and peripheral blood immunoregulatory lymphocytes in patients with myelodysplastic syndrome.

The cell surface phenotype of immunoregulatory lymphocytes in bone marrow (BM) and peripheral blood (PB) in myelodysplastic syndrome (MDS), a stem cell disorder, was analyzed. Mononuclear cells from 25 patients with refractory anemia (RA) and nine with RA with an excess of blasts (RAEB) were characterized by two-color flow cytometry using various monoclonal antibodies. No significant change of CD3+, CD4+, and CD8+ cells in PB, but a decrease of the percent of positive cells for CD8++ among the total lymphocyte (%CD8++) was noticed in RA patients. On the other hand, in BM of RA patients, a decrease in the number of CD4+ cells, but not CD8++ cells, was noted. In RAEB patients, the absolute numbers of CD3+, CD4+, CD8+, and CD8++ cells in BM were decreased; however, the ratio of these lymphocytes was not changed. No change was observed among the CD4+ subsets in PB of RA or RAEB patients. In BM, a decrease in percentage of CD4+CD45RA+ (%CD4+CD45RA+; naive cell) and increases in CD4+CD45RO+ (%CD4+CD45RO+; memory cell) and CD4+CD29+ (%CD4+CD29+; helper/inducer) among CD4+ cells were found in both RA and RAEB patients. Analysis of the CD8++ subset showed an increased number of CD8++CD11a+ cells (activated CTL) in both BM and PB of RA patients, but not of RAEB patients. Furthermore, increments in CD56+ and CD16+ cells among CD3- cells (natural killer; NK cells) were seen in RA patients but not in RAEB patients. It remains unclear whether lymphocytes in MDS patients were involved in the abnormal (MDS) clones, but our results regarding the increments of CD8++CD11a+ and NK cells in RA patients suggest that the mechanism of immune surveillance against the abnormal MDS clones was activated in these RA patients, but not in RAEB patients. Further investigation is required to clarify the functions of these immunoregulatory lymphocytes in MDS patients.

Adult↗

Surgical management of infective endocarditis associated with cerebral complications. Multi-center retrospective study in Japan.

To establish guidelines for the surgical treatment of patients with infective endocarditis who have cerebrovascular complications, we conducted a detailed retrospective study of 181 of 244 patients with cerebral complications among 2523 surgical cases of infective endocarditis of the Japanese Association of Thoracic Surgery. The results showed that 9.7% of all patients with infective endocarditis had associated cerebral complications: 108 (44.3%) had active native valve endocarditis, 96 (39.3%) had healed native valve endocarditis, and 40 (16.4%) had prosthetic valve endocarditis. The hospital mortality of the patients with cerebral complications was 11.0% in the group as a whole: 13.9% in active native valve endocarditis, 3.1% in healed native valve endocarditis, and 37.5% in prosthetic valve endocarditis. Diseased valves included the following aortic valve in 55.5%, mitral valve 49.8%, tricuspid valve in 1.3%, and pulmonary valve in 1.3%. In 181 patients with cerebral complications, organisms were detected as follows: gram-positive cocci in 133 (73.5% [Streptococcus in 85, Staphylococcus in 32]), gram-negative in 18 (9.9%), fungus in 11 (6.1%), and unknown in 64.6%, cerebral bleeding in 31.5%, cerebral abscess in 2.8%, and meningitis in 1.1%. Hospital mortality rate and an exacerbation rate of cerebral complications, including related death, according to the interval from onset of cerebral infarction to cardiac surgery, were as follows: 66.3% and 45.5% within 24 hours, 31.3% and 43.8% between 2 and 7 days, 16.7% and 16.7% between 8 and 14 days, 10.0% and 10.0% between 15 and 21 days, 26.3% and 10.5% between 22 and 28 days, and 7.0% and 2.3% over 4 weeks later, respectively. A significant correlation existed between the interval and the exacerbation of cerebral complications (tied p = 0.008). Preoperative risk factors affecting exacerbation of cerebral complications were as follows: (1) severity of cerebral complications (p = 0.006), (2) intervals (p = 0.012), and (3) uncontrolled congestive heart failure as indications for cardiac surgery (p = 0.014). One patient underwent a cardiac operation within 24 hours of the onset of cerebral hemorrhage and died of cerebral damage. No exacerbations occurred in 10 patients who underwent their operation between 2 and 28 days. Nevertheless, exacerbations occurred in 19.0% of patients whose operation was done more than 4 weeks later. These data suggest that cardiac operations can be done safely 4 weeks after cerebral infarction, and if the delay is more than 2 weeks, the exacerbation rate will be around 10%. The risk of progression of cerebral damage is still significant 15 days and even 4 weeks after cerebral hemorrhage.

Adult↗

Kinetics and mechanism of photocycloaddition of deoxyuridines to 2,3-dimethyl-2-butene.

The mechanism of photocycloaddition of 2'-deoxyuridine (1a) and thymidine (1b) to 2,3-dimethyl-2-butene (Bu) in acetonitrile by UV irradiation has been studied. The reciprocal quantum yield for the cycloaddition increased linearly with reciprocal concentrations of Bu in acetonitrile to give limiting quantum yields at infinite concentration of Bu as 0.030 and 0.0096 for 1a and 1b, respectively. This shows that the cycloaddition proceeds in a two-step mechanism between the triplet state of 1 and Bu through biradical intermediates. Addition of cis-1,3-pentadiene quenched the reaction obeying the Stern-Volmer equation. The above quenching experiments and laser transient spectroscopy revealed that the triplet state of 1a reacts with Bu with much larger rate constant (1.3-1.6 x 10(9) M-1 s-1) than that of 1b (4-5 x 10(7) M-1 s-1) reflecting larger steric hindrance exerted in the reaction of 1b than that of 1a.

Alkenes↗

[Analysis of T cell subsets in autoimmune hemolytic anemia patients].

To clarify a role of immunoregulatory T cells in the pathophysiology of autoimmune hemolytic anemia (AIHA), we investigated T cell subsets in the peripheral blood of 15 patients with AIHA by two color analysis using flow cytometry. Consequently both CD4+ cells and CD4+CD45RA+ cells decreased in proportion, irrespective of the disease activity (active or remission phase). CD4+CD45RA+ cells are regarded as naive T cells. Incidentally the ratio of CD45RA+ cells in CD4+ cells also fell in the low level in active phase, but it recovered to the normal ratio in remission. On the other hand, CD8+ cells and CD8+ +S6F1+ cells that may represent activated cytotoxic T lymphocytes increased in active phase and then both entered the normal range in remission. These findings suggest that AIHA could be caused partly by the alternative balance of CD4+CD45RA+ cells probably constituting a member of IRT and moreover by the activation of CTL.

Anemia, Hemolytic, Autoimmune↗

[Cytofluorometric analysis of tumor cell size and follicle formation of B-cell lymphomas].

In order to investigate the size variation of neoplastic B cells (NBC) from lymph nodes of patients with B-cell lymphomas (BCL), we carried out two-dimensional analysis by flow cytometry (FCM) using the forward light scatter (FLS) and the fluorescence intensity (FI) of surface immunoglobulin light chain (sIgL). NBC were identified as having the homogeneous characteristics of both FLS and tumor-restricted sIgL (kappa or lambda). The FLS variation of NBC was then analyzed using CD3+ T-cells as a scale control. The results closely coincided with the cell types determined by the pathologic diagnosis. Secondly, we used FCM to investigate how strongly NBC express VLA-4 alpha and LFA-1 alpha, which seemed to play important roles in neoplastic follicle formation. The expression intensities of these molecules were classified into three grades (-, + & ++). The results were presented in the order of VLA-4 alpha and LFA-1 alpha; follicular 8/15 (++/++), 6/15 (++/+), 1/15 (+/++), partially follicular 3/5 (+/++), 2/5 (+/+), diffuse 2/16 (++/-), 6/16 (+/++), 8/16 (+/+), B-CLL 8/8 (-/+ or -). These findings suggest that follicular lymphomas are phenotypically distinguishable from diffuse lymphomas.

B-Lymphocytes↗

[Changes in neuropsychological functions following cardiovascular surgery].

This study was designed to elucidate if there is a potential hazard of developing neuropsychological deterioration after major cardiovascular surgery. Neuropsychological functions were studied in 49 patients before and after cardiac (coronary artery bypass, cardiac valve replacement, etc.) and thoracic aortic surgery (aortic aneurysm). Neuropsychological examinations using 5 batteries (Mini-Mental State Examination, Cross Cultural Cognitive Examination, Miyake's Verbal Memory Test, Benton Visual Retention Test and Wisconsin Card Sorting Test) were performed before surgery and subsequently at 3 weeks and 8 months after. Twenty-five of 49 patients (51%) showed a significant deterioration at least in one of the test batteries. There was no significant relation between age or educational levels and post-surgical impairment of cognitive function. The impairment of cognitive function was found mainly in the "memory function". Follow up examinations were carried out on 31 of the 49 patients 8 months after surgery. Among these patients, 13 patients did not show any changes in cognitive function throughout the study period. Eleven of the 16 patients who developed a decrease in cognitive function for a certain period after surgery (3 weeks), recovered to the same level at the follow-up examination that it was prior to the surgery. Cognitive function in five patients did not improve and remained at the decreased level. The other two patients whose function was normal at the first post-surgical examination, were found to have developed impairment of cognitive function at the follow up. Although the patients had some deficits on their neuropsychological function, they scarcely complained about any problems in their daily life.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Relationship between retained microbubbles and neuropsychologic alterations after cardiac operation].

We studied the relationship between quantity of microbubble retained in the left heart and neuropsychologic alterations after surgery in 21 patients undergoing cardiac surgery including cardiopulmonary bypass. The neuropsychologic change was evaluated by three kinds of psychological test, which mainly analyzed memory and cognition. The microbubble was continuously monitored by the long axis view of the descending aorta of transesophageal echocardiography and then quantitatively analyzed and graded by the on-line computer. More microbubbles were detected in the valve surgery requiring the intracardiac procedure than in coronary artery bypass grafting and neuropsychologic deterioration, although the relationship did not reach statistical significance. Since most of the microbubbles were detected during the unclamping of aorta and the weaning from cardiopulmonary bypass, a technical improvement of the surgical procedures could reduce them. We think that transesophageal echocardiography is useful for monitoring microbubbles during operation.

Adult↗

[Gamma delta T cells in peripheral blood and in bronchoalveolar lavage fluid from patients with sarcoidosis and idiopathic pulmonary fibrosis].

We measured levels of gamma delta T cells in peripheral blood and in bronchoalveolar lavage fluid from patients with sarcoidosis, from patients with pulmonary fibrosis, and from normal subjects. In blood from both groups of patients, the percentage of lymphocytes was significantly greater than normal. The number of CD3+ cells per cubic millimeter was significantly lower than normal in patients with sarcoidosis, and tendency to be lower than normal in patients with pulmonary fibrosis. The percentage of CD3+ cells tended to be low, but there was no significant difference. The percentage and number of gamma delta T cells in patients with sarcoidosis, and the number of gamma delta T cells in patients with pulmonary fibrosis tended to be high. In bronchoalveolar lavage fluid, the percentage of lymphocyte was significantly higher than normal, and the numbers of CD3+ cells and gamma delta T cells per cubic millimeter tended to be high. In both groups of patients, cell counts of lymphocytes were significantly higher than normal. Numbers of CD3+ cells and of gamma delta T cells were significantly higher than normal in patients with sarcoidosis, and tended to be higher than normal in those with pulmonary fibrosis. These findings indicate local activation of gamma delta T cell function, recruitment of these cells into the bronchoalveolar system, and augmentation of gamma delta T cell supply in the whole body, especially in patients with sarcoidosis. In patients with pulmonary fibrosis the results were inconclusive; they were not as striking as were the results in patients with sarcoidosis.

Adult↗

Cytotoxic lymphocytes in the peripheral blood of patients with B cell lymphomas.

In order to analyze systemic immune surveillance in patients with B cell non-Hodgkin's lymphomas (B-NHL), we investigated circulating lymphocytes using two-color flow cytometry. The proportions of CD3-CD56+ natural killer (NK) cells and CD8++(bright) S6F1++ killer-effector T cells corresponding to activated cytotoxic T lymphocytes (aCTL) were studied in the peripheral blood of 26 patients with indolent lymphoma (IL) and 24 with aggressive lymphoma (AL). The AL patients with both limited disease and advanced disease had an increased proportion of NK cells. However, this feature was not evident in IL patients with either limited or advanced disease. In contrast, an increased proportion of aCTL was observed only in IL patients with advanced disease. These findings indicate that IL may differ from AL in terms of immune surveillance against neoplastic B cells.

Adult↗

Periventricular white matter lucency and cerebral blood flow autoregulation in hypertensive patients.

The goal of this study was to elucidate the association between the development of periventricular white matter lucency and autoregulation of cerebral blood flow in hypertensive patients through the arteriovenous oxygen saturation difference method. We studied 51 hypertensive patients who had previously suffered from minor strokes (lacunar infarction, 43; deep basal minor hemorrhage, 8). Patients were divided into three groups based on the findings of periventricular white matter lucency. We measured the absolute value of resting cerebral blood flow using the argon inhalation method, and stepwise reduction of blood pressure was obtained with patients on a tilting table. Intracerebral venous blood sampling was accomplished by direct cannulation into the jugular vein up to the jugular bulb. We calculated several cerebral circulatory parameters, such as cerebrovascular resistance and cerebral oxygen consumption, and also delineated individual autoregulation curves. Cerebrovascular resistance was significantly greater in patients with severe periventricular white matter lucency than in patients without it (P < .05). Impaired autoregulation was also significantly more prevalent in patients with more severe periventricular lesions (P < .05). Multiple regression analysis revealed that the impaired autoregulation was significant and an independent determinant of the severity of such periventricular lesions (R = .34, P < .05). In conclusion, our findings indicated that hypertensive patients with severe periventricular white matter lucency were more likely to have impaired autoregulation of cerebral blood flow and suggest that stricter blood pressure control is required in such patients to prevent deterioration of the cerebral microcirculation.

Aged↗

Very early demonstration of secondary pyramidal tract degeneration by computed tomography.

BACKGROUND: While magnetic resonance imaging has revealed progressive changes in the pyramidal tract in accordance with histopathologic stages of wallerian degeneration secondary to a supratentorial lesion, computed tomography (CT) has only demonstrated a shrinkage of the pyramidal tract in the midbrain or pons during the chronic stage. We present a patient with frontoparietal subcortical hemorrhage in whom serial CT scans clearly demonstrated wallerian degeneration along the axis of the pyramidal tract early in the acute stage. CASE DESCRIPTION: A 63-year-old man with a history of hypertension suddenly developed a deterioration of consciousness, transcortical mixed aphasia, and dense hemiplegia on the right side. CT scans revealed a massive intracerebral hematoma in the frontoparietal subcortices of the left hemisphere. Although initial CT did not detect any hypodense areas along the left pyramidal tract below the hematoma, ill-defined areas of decreased density appeared in the posterior limb of the internal capsule, cerebral peduncle of the midbrain, and pontine base of the left side on day 13 after the stroke. These areas became well demarcated on day 22 and persisted thereafter. CONCLUSIONS: An extensive hematoma can interrupt the pyramidal tract fibers that arise not only from the motor cortex and caudal premotor cortex but also from the somatosensory and parietal cortices, allowing very early CT demonstration of wallerian degeneration of the pyramidal tract.

Cerebral Hemorrhage↗