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Biomedical subjects

M Sekiguchi

Publications and source records attributed to M Sekiguchi.

At least 91 records · Page 5Linked to original sources
PubMed1999

Ultrastructural features of the myocardium of children with dilated cardiomyopathy.

We analyzed the electron-microscopic features of endomyocardial biopsy from pediatric patients with dilated cardiomyopathy (DCM). The specimens examined were taken from the right ventricle of ten patients aged from 2 to 15 years (mean 9.7 years). Biopsy specimens from eight patients with congenital heart disease (tetralogy of Fallot), aged from 3 to 12 (mean 7.3 years), and ten adult patients with DCM, aged from 32 to 60 (mean 45 years), were also examined. Patients considered to have endocardial fibroelastosis, arrhythmogenic right ventricular cardiomyopathy, specific cardiomyopathy, or coronary heart disease were excluded from this study. Specimens from pediatric patients with DCM showed various degrees of ultrastructural abnormalities of myocytes, including myofibrillar fragmentation, mitochondrial abnormalities, and intracellular edema. The ultrastructurally determined contractility failure index based on the severity of myocardial degeneration at the electronmicroscopic level was 4.9 +/- 1.1. This value was significantly higher than that in patients with tetralogy of Fallot (0.9 +/- 0.6, P < 0.001) but was not significantly different from that in adult patients with DCM (6.1 +/- 2.6). The index of pediatric patients with DCM who died within 3 years was high (6.0 +/- 0.8). Basal lamina layering of a capillary (BLL) in the myocardium was revealed in 1 of the 10 (10%) pediatric patients with DCM and in 6 of the 10 (60%) adult patients with DCM (P < 0.05). No BLL was noted in the patients with tetralogy of Fallot. These findings may be related to the pathogenesis of DCM in children and adults.

Adolescent↗
PubMed1999

Improvement of eosinophilic heart disease after steroid therapy: successful demonstration by endomyocardial biopsied specimens.

A 62-year-old man with acute eosinophilic endomyocarditis developed congestive heart failure. The biopsy specimens revealed degranulated eosinophils and eosinophil cationic protein (ECP) in the endocardium, and in activated eosinophils and the myocardial interstitium. On electronmicroscopy, a characteristic cardiac myocytolytic change showing disruption at the intercellular junctional site was observed. After steroid treatment, clinical symptoms, systolic dysfunction and laboratory data dramatically improved. In the subsequent biopsy specimens, eosinophilic infiltration and ECP disappeared. Steroid therapy provided a beneficial effect in preventing the progression of cardiac damage. This effect was clearly documented by histochemical studies of the serial endomyocardial biopsy samples.

Biopsy↗
PubMed1999

Expression patterns of type II pneumocyte apical surface glycoconjugates in lung adenocarcinoma cells.

Monoclonal antibodies and lectins were used to examine the expression patterns of apical membrane oligosaccharide sequences specific to type II pneumocytes in atypical adenomatous hyperplasia (AAH) and lung cancer. Atypical cells of AAH and papillary adenocarcinoma cells expressed abundant sialyl Thomsen-Friedenreich (TF) antigen: this was not observed in acinar adenocarcinoma, bronchioloalveolar carcinoma with mucin production or squamous cell carcinoma. Sialyl Tn antigens was also detected on a few cells in AAH and papillary adenocarcinomas. Asialo TF and Tn antigen were not observed on the surface of carcinoma cells of any type. Alpha(alpha)2,3-linked sialic acids predominated in type II pneumocyte, AAH and papillary adenocarcinoma, whereas ciliated columnar cells expressed alpha2,6-linked sialic acids. Lewisx and sialyl Lewisx antigens capped the TF antigen in both O- and N-linked side chains on the surface of AAH and papillary adenocarcinoma cells, but were not expressed by type II pneumocytes. The findings demonstrate that papillary adenocarcinoma cells resemble type II pneumocytes in that they express abundant sialyl TF surface antigen, but they also express TF-related antigens not found in type II pneumocytes. Apical surface glycoconjugates of AAH have structural characteristics shared by both type II pneumocytes and papillary adenocarcinoma cells.

Adenocarcinoma↗
PubMed1999

Immunoblastic lymphadenopathy-like T-cell lymphoma complicated by multiple gastrointestinal involvement.

We report a rare case of immunoblastic lymphadenopathy (IBL)-like T-cell lymphoma complicated by multiple gastrointestinal involvement, which appeared to be ameliorated by chemotherapy but resulted in perforative peritonitis. A 66-year-old Japanese woman who had generalized lymphadenopathy and eruptions was admitted to our hospital because of bloody stool. Colonoscopic examination revealed hemorrhagic ulcers in the terminal ileum and a saucer-like ulcer in the cecum. Gastrointestinal endoscopy revealed several ulcerative or elevated lesions in stomach and duodenum. Biopsy specimens of these lesions and of a lymph node showed characteristic histological features of IBL-like T-cell lymphoma. The initial treatment with prednisolone (PSL) and cyclophosphamide (CPA) was effective. Six months after the treatment, however, she developed bloody stool again caused by multiple ulcerative lesions in the large intestine. The recurrence of the disease was determined histologically, and four courses of CPA, PSL, vinblastine sulfate and doxorubicin hydrochloride (CHOP) therapy were administered. One month after completing the CHOP therapy, she developed intestinal obstruction and then acute peritonitis resulting from perforation at an ulcer scar in the jejunum. Surgical treatment was successful, and histological examination demonstrated no lymphoma cells in the resected specimen. A gastrointestinal perforation should be recognized as a potential complication of IBL-like T-cell lymphoma, even during remission.

Aged↗
PubMed1999

Effects of intensive lipid lowering by low-density lipoprotein apheresis on regression of coronary atherosclerosis in patients with familial hypercholesterolemia: Japan Low-density Lipoprotein Apheresis Coronary Atherosclerosis Prospective Study (L-CAPS).

Twenty-five heterozygous familial hypercholesterolemic patients treated with LDL-apheresis and drugs and 11 patients treated with drugs underwent follow-up angiography 2.3 years later. One-hundred thirteen lesions were measured by quantitative angiography. Mean LDL-cholesterol levels during the trial were 140 +/- 34 mg/dl in the apheresis group and 170 +/- 58 mg/dl (P < 0.05) in the control group. The mean changes in minimal lumen diameter of lesions were +0.19 +/- 0.30 mm (improved) in the apheresis group (n = 76) and -0.44 +/- 0.40 mm (worsened) in the control group (n = 37) (P < 0.0001). When progression and regression were defined as a change in minimal lumen diameter of +/- 0.67 mm, in the apheresis group, two (8%) patients had progression, 19 (76%) stayed unchanged and four (16%) had regression, but in the control group seven (64%) patients had progression and four (36%) stayed unchanged. The frequency of regression or no change was significantly higher in the apheresis group than in the control group (P < 0.004). Intensive cholesterol lowering therapy with LDL-apheresis and lipid lowering drugs can achieve a substantial decrease in LDL-cholesterol levels to induce regression of coronary lesions in familial hypercholesterolemic patients with advanced coronary artery disease.

Adult↗
PubMed1999

Differential Th1 and Th2 cell regulation of murine cardiac allograft acceptance by blocking cell adhesion of ICAM-1/LFA-1 and VCAM-1/VLA-4.

Administration of anti-intercellular adhesion molecule (ICAM)-1 monoclonal antibody (mAb) plus anti-lymphocyte function associated antigen (LFA)-1 mAb induces tolerance in murine cardiac transplantation, while anti-vascular cell adhesion molecule (VCAM)-1 mAb plus anti-very late antigen (VLA)-4 mAb administration prolongs graft survival, but leads to tolerance only in some cases. BALB/c mice hearts were transplanted into C3H/He recipients. Each combination of anti-VCAM-1 plus anti-VLA-4 mAbs (100 microg each/day, i.p.) or anti-ICAM-1 plus anti-LFA-1 mAbs (50 microg each/day, i.p.) was administered for 5 days. For control study, third group mice received daily with FK506 administration (1 mg/kg/day). The cardiac allografts and recipients' spleens were harvested on day 7; the expression of cytokines were detected using immunohistochemistry, reverse transcription-polymerase chain reaction (RT-PCR) and in situ RT-PCR. Th2 cytokines (IL-4 and IL-10) were markedly enhanced and Th1 cytokines (IFN-gamma and IL-2) were suppressed in recipients treated with anti-ICAM-1 mAb plus anti-LFA-1 mAb, while poor Th2 cytokine expression allowed persistent Th1 cytokine expression in recipient mice with anti-VCAM-1 mAb plus anti-VLA-4 mAb treatment. Both Th1 and Th2 cytokine expression was suppressed in FK506-treated mice. It is concluded that immunological tolerance and prolonged graft survival induced by blocking cell adhesion is regulated by different cytokine expression.

Animals↗
PubMed1999

Clustered adenine/thymine stretches are essential for function of a fission yeast replication origin.

We have determined functional elements required for autonomous replication of the Schizosaccharomyces pombe ars2004 that acts as an intrinsic chromosomal replication origin. Internal deletion analysis of a 940-bp fragment (ars2004M) showed three regions, I to III, to be required for autonomously replicating sequence (ARS) activity. Eight-base-pair substitutions in the 40-bp region I, composed of arrays of adenines on a DNA strand, resulted in a great reduction of ARS activity. Substitutions of region I with synthetic sequences showed that no specific sequence but rather repeats of three or more consecutive adenines or thymines, without interruption by guanine or cytosine, are required for the ARS activity. The 65-bp region III contains 11 repeats of the AAAAT sequence, while the 165-bp region II has short adenine or thymine stretches and a guanine- and cytosine-rich region which enhances ARS activity. All three regions in ars2004M can be replaced with 40-bp poly(dA/dT) fragments without reduction of ARS activity. Although spacer regions in the ars2004M enhance ARS activity, all could be deleted when an 40-bp poly(dA/dT) fragment was added in place of region I. Our results suggest that the origin activity of fission yeast replicators depends on the number of adenine/thymine stretches, the extent of their clustering, and presence of certain replication-enhancing elements.

AT Rich Sequence↗
PubMed1999

Assessment of myocardial fatty acid metabolic abnormalities in patients with idiopathic dilated cardiomyopathy using 123I BMIPP SPECT: correlation with clinicopathological findings and clinical course.

OBJECTIVE: To determine the clinical and prognostic value of identifying metabolic abnormalities of myocardial fatty acid metabolism in idiopathic dilated cardiomyopathy using iodine-123 beta-methyl-iodophenyl pentadecanoic acid (123I BMIPP). SETTING: Cardiac care division in national hospital. PATIENTS: 32 consecutive patients with idiopathic dilated cardiomyopathy in whom both 123I BMIPP and thallium-201 myocardial single photon emission computed tomography were performed. METHODS: The uptake of each tracer was scored visually from 0 (normal) to 3 (defect) in 17 segments (eight basal, eight midventricular, and one apical). A total score for all 17 segments was compared with clinicopathological variables. Prognostic value of mismatches between the two tracers were also evaluated. RESULTS: The 123I BMIPP total score was correlated with pulmonary capillary wedge pressure (r = 0.68, p < 0.001), left ventricular end diastolic pressure (r = 0.65, p < 0.001), percentage fractional shortening at six months' follow up (r = -0.58, p = 0. 001), myocyte diameter (r = 0.66, p < 0.001), and percentage area of interstitial fibrosis (r = 0.69, p < 0.001) measured by morphometry in the biopsy specimens. During a mean (SD) follow up of 20 (11) months, deterioration of the New York Heart Association functional class was observed in 11 of the 32 patients; four of these died. Segments with a greater decrease in 123I BMIPP than thallium-201 uptake (type B mismatching) were often observed in patients with deterioration (88/187, 29% v 58/357, 16%; p < 0.001). CONCLUSIONS: The extent of the abnormality of myocardial fatty acid metabolism in idiopathic dilated cardiomyopathy reflects the severity of haemodynamic deterioration and histopathological changes. Type B mismatching is one of the important prognostic indicators in idiopathic dilated cardiomyopathy.

Adult↗
PubMed1999

Interferon-gamma increases CD62L expression on human eosinophils.

BACKGROUND: L-selectin (CD62L) and Mac-1 (CD11b/CD18) play a crucial role in the infiltration of eosinophils. However, changes in CD62L and CD11b expression on eosinophils after stimulation with cytokines were little studied. METHODS: Eosinophils in peripheral blood of healthy volunteers were purified and cultured with interleukin-5 (IL-5), granulocyte/macrophage colony-stimulating factor (GM-CSF) or interferon-gamma (IFN-gamma). After up to 24 h incubation, CD62L and CD11b expression were examined using flow cytometry. The effects of dexamethasone (Dex), cycloheximide (CHX) or theophylline on CD62L expression on IFN-gamma-stimulated eosinophils were also studied. RESULTS: IL-5 or GM-CSF downregulated CD62L and upregulated CD11b expression on eosinophils after 30 min stimulation. Conversely, IFN-gamma upregulated CD62L after 12 h stimulation in a time- and dose-dependent manner, and had no effect on CD11b expression. Dex, CHX or theophylline dose-dependently decreased CD62L expression on IFN-gamma-stimulated eosinophils. CONCLUSIONS: IFN-gamma is a particular cytokine which can increase CD62L expression on circulating or infiltrated human eosinophils. It is suggested that protein synthesis and intracellular cAMP participate in the increase in L-selectin expression on IFN-gamma-stimulated eosinophils.

Antineoplastic Agents↗
PubMed1999

Proliferation of type II pneumocytes and alteration in their apical surface membrane antigenicity in pulmonary sarcoidosis.

STUDY OBJECTIVE: To evaluate both the proliferation of type II pneumocytes in the alveolitis associated with pulmonary sarcoidosis and any alteration in their surface membrane antigenicity. MATERIALS AND METHODS: We investigated 20 transbronchial lung biopsy (TBLB) specimens from 20 patients with pulmonary sarcoidosis, 7 TBLB specimens from 7 sarcoidosis patients without pulmonary involvement, and 19 normal lung specimens, using colloidal iron stain and immunostaining with anti-Thomsen-Friedenreich (TF) antigen and anti-surfactant protein-A monoclonal antibodies. RESULTS: The density of type II pneumocytes was significantly higher in the pulmonary sarcoidosis specimens ([mean +/- SD] 11.1+/-3.7 per 1 mm alveolar septal length) than in the nonpulmonary sarcoidosis (7.8+/-1.3) or normal lung specimens (7.2+/-0.8). TF antigen was directly expressed on the apical surface of some type II pneumocytes in the pulmonary sarcoidosis specimens, but it was completely masked by sialic acids in the nonpulmonary sarcoidosis specimens and in the normal lung tissues. CONCLUSIONS: In pulmonary sarcoidosis, type II pneumocytes proliferated and the antigenicity of the surface membrane was altered. It is suggested that these type II pneumocytes may be vulnerable to injury by natural anti-TF antibodies that are cytotoxic when present with complement. This damage may decrease alveolar surfactant and cause focal alveolar collapse proceeding to pulmonary fibrosis in some cases of pulmonary sarcoidosis.

Antigens, Surface↗
PubMed1999

Ultrastructural studies on the formation and distribution of lipid droplets in the lung capillary endothelial cells in patients with sarcoidosis.

BACKGROUND AND AIM OF THE WORK: We previously reported the presence of definite morphological alterations in the capillary endothelium of sarcoid lung. The aim of this study was to examine ultrastructural changes and distribution of lipid droplets in the endothelium of lung capillaries of patients with sarcoidosis. METHODS: Tissue specimens were obtained by transbronchial lung biopsy or open lung biopsy from 16 patients with sarcoidosis and 13 controls. Biopsies were evaluated by electron microscopy following lead citrate and uranyl acetate staining. RESULTS: Typical lipid droplets were observed in pulmonary capillaries of 11 out of 16 sarcoid patients (69%); the droplet frequency was higher in sarcoid patients than in control specimens. Lipid droplets were characterized by biphasic density: most droplets contained eccentrically located vacuoles (saturated fatty acids) others were characterized by low density areas (unsaturated fatty acids). Biphasic droplets were covered by large lysosomal granules and were mainly distributed in the endothelium and pericytes. Interestingly, in the latter, vacuoles increased in size while small amounts of lysosomal granules were detectable. CONCLUSION: Our findings suggest that biphasic droplets increase in number in pulmonary capillaries of patients with sarcoidosis with a characteristic distribution pattern from the endothelium to pericytes.

Adult↗
PubMed1999

[Problems with employment of a staff anesthesiologist in a local hospital].

Yukiguni Yamato General Hospital (199 beds) is one of main local hospitals of Minamiuonuma area in Niigata prefecture. From June 1997, an anesthesiologist has been employed as a staff of this hospital instead of parttimers. We examined whether employment of an anesthetic staff was useful for a local hospital or not, in terms of clinical and cost advantages. There were benefits in explaining the nature of anesthesia, possible risks, operating room and pre-postoperative procedures to the patients. And there were advantages in reducing anesthetic management fee, in shortening the staying time in operating room. We conclude that there are many benefits in obtaining an anesthesiologist for a local hospital staff, but there are some drawbacks in having to work alone.

Anesthesiology↗
PubMed1999

[Estimation of pulmonary hypertension in lung and valvular heart diseases by perfusion lung scintigraphy].

To estimate pulmonary hypertension, we measured postural differences in pulmonary blood flow for the lateral decubitus positions on perfusion lung scintigrams with Tc-99 m macro-aggregated albumin, applying the method devised by Tanaka et al (Eur J Nucl Med 17: 320-326, 1990). Utilizing a scintillation camera coupled to a minicomputer system, changes in the distribution of pulmonary blood flow caused by gravitational effects, namely, changes in the total count ratios for the right lung versus the left lung in the right and left lateral decubitus positions (R/L), were obtained for 44 patients with lung disease, 95 patients with valvular heart disease, and 23 normal subjects. Mean standard deviation in the R/L ratios was 3.09 +/- 1.28 for the normal subjects, 1.97 +/- 0.89 for the patients with lung disease, and 1.59 +/- 0.59 for the patients with valvular heart disease. The R/L ratios correlated with mean pulmonary arterial pressure and cardio-thoracic ratios in the lung disease and valvular heart disease groups, with pulmonary arteriolar resistance in the former, and with pulmonary capillary wedge pressure in the latter. Defining pulmonary hypertension (> 20 mmHg) as an R/L ratio of less than 1.81, which is the mean-1 standard deviation for normal subjects, the sensitivity and the specificity of the R/L ratio for the diagnosis of pulmonary hypertension were 62.9% and 76.2%, respectively, for the lung disease patients, and 80.3% and 61.8%, respectively, for the valvular heart disease patients. This method seems to be useful for the pathophysiologic evaluation of pulmonary perfusion in cases of lung disease and valvular heart disease.

Adult↗
PubMed1999

[Amyopathic dermatomyositis with interstitial pneumonia: effective treatment with cyclophosphamide pulse therapy].

A 42-year-old man was admitted to our hospital because of dyspnea on exertion, skin eruptions on the face and extremities, and interstitial shadows mainly in the lower fields of both lungs. Characteristic skin lesions and skin biopsy findings without muscle symptoms or elevated CPK resulted in a diagnosis of amyopathic dermatomyositis (ADM). Thoracoscopic lung biopsy specimens disclosed BOOP-type interstitial pneumonia. Oral prednisolone (PSL) was initiated at 60 mg/day and gradually tapered. However, because his respiratory symptoms and laboratory findings deteriorated, the patient underwent 5 courses of cyclophosphamide (CPA) pulse therapy. Following improvement of his subjective symptoms, arterial blood gas data, and respiratory functions, the patient was discharged and placed on oral PSL and CPA. CPA was discontinued 18 months later. The patient has continued to receive PSL (5 mg/day) and has been in good condition for 3 years. Though the prognosis for interstitial pneumonia associated with ADM is reported to be poor, our patient represented a rare case of BOOP-type interstitial pneumonia brought into remission by CPA pulse therapy.

Adult↗
PubMed1999

[Primary ciliary dyskinesia treated with living-donor lobar lung transplantation].

We report a case of primary ciliary dyskinesia in which a living-donor lobar lung transplant was performed. A 24-year-old woman with a diagnosis of primary ciliary dyskinesia and bronchiectasis was admitted to Shinshu University Hospital because of persistent dyspnea and pyrexia over a period of 4 months. Although she was given various antibiotics, neutrophilia, elevated plasma C-reactive protein (CRP) levels, and respiratory failure persisted. Chest roentgenograms and computed tomography disclosed severe bronchiectasis and diffuse infiltrative shadows in both lung fields. Pseudomonas aeruginosa was detected in a sputum culture. Although a variety of conventional therapies were administered, the patient's oxygenation progressively deteriorated. She was intubated and assisted by mechanical ventilation. The patient and her family proposed lung transplantation, and we concluded that a living-donor lobar lung transplant would be a suitable treatment for her disease. We transported the patient to Okayama University Hospital by helicopter 10 days after intubation. A living-donor lobar lung transplant was successfully performed with lung tissues donated by the patient's mother and sister for each transplant site.

Adult↗