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Biomedical subjects

S Aoki

Publications and source records attributed to S Aoki.

At least 217 records · Page 12Linked to original sources
PubMed1997

Characterization and sensitivity to interleukin 2 and interferon alpha of leukemic cells from a patient with large granular lymphocytic leukemia associated with chronic active Epstein-Barr virus infection.

A patient presented with chronic large granular lymphocyte leukemia associated with chronic active Epstein-Barr virus infection (CAEBV). Cell cycle analysis revealed a minimal growth compatible with chronic lymphocytic leukemia After 5 months of treatment, the patient died from acute transformation of the leukemia. Cell harvested during chronic phase were analyzed for sensitivity to interleukin 2 (IL-2) and interferon alpha (IFN alpha) in vitro by means of surface phenotyping and cell cycle assay. IL-2 induced remarkable growth of the cells, whereas IFN alpha did not confer a growth advantage. Since IFN alpha was expected to have no growth induction effect on the leukemia cells, it was administered to the patient to treat the CAEBV.

Antineoplastic Agents↗
PubMed1997

Three-dimensional ultrasonography in the first trimester of human pregnancy.

Our purpose was to visualize normal embryonal and fetal surface anatomical structures in the first trimester of human pregnancy by use of three-dimensional ultrasonography with a specially developed abdominal three-dimensional transducer. Four embryos and 31 fetuses of 8-13 weeks gestation were studied with a specially-developed abdominal three-dimensional transducer (3.5 MHz). This imaging system can provide conventional two-dimensional ultrasonography images and can also generate, within seconds, high-quality three-dimensional images in the surface and transparent mode with no need for an external workstation. The percentage of surface anatomical structures visualized at each gestational age interval using two-dimensional and three-dimensional ultrasonography is presented. Head and trunk were depicted in all cases. The number and the clarity of visualization of face, upper and lower extremities, hand, and foot increased with advancing gestation. The free loop of the umbilical cord was depicted in most cases. The number of depictions of abdominal cord insertion, midgut herniation, and yolk sac decreased with the increase of gestation. Genitals could not be identified in the first trimester. The ability to view some surface anatomical structures (face, hand, and foot) was better with three-dimensional ultrasonography than with two-dimensional ultrasonography. Three-dimensional ultrasonography provides a novel means for visualization of surface anatomical structures of the embryo and early fetus. These results suggest that three-dimensional ultrasonography can become an important modality in future embryological and early fetal research and in detection of embryonic and fetal developmental disorders in the first trimester of pregnancy.

Cross-Sectional Studies↗
PubMed1997

Circadian rhythm of the cyanobacterium Synechocystis sp. strain PCC 6803 in the dark.

The cyanobacterium Synechocystis sp. strain PCC 6803 exhibited circadian rhythms in complete darkness. To monitor a circadian rhythm of the Synechocystis cells in darkness, we introduced a PdnaK1::luxAB gene fusion (S. Aoki, T. Kondo, and M. Ishiura, J. Bacteriol. 177:5606-5611, 1995), which was composed of a promoter region of the Synechocystis dnaK1 gene and a promoterless bacterial luciferase luxAB gene set, as a reporter into the chromosome of a dark-adapted Synechocystis strain. The resulting dnaK1-reporting strain showed bioluminescence rhythms with a period of 25 h (on agar medium supplemented with 5 mM glucose) for at least 7 days in darkness. The rhythms were reset by 12-h-light-12-h-dark cycles, and the period of the rhythms was temperature compensated for between 24 and 31 degrees C. These results indicate that light is not necessary for the oscillation of the circadian clock in Synechocystis.

Circadian Rhythm↗
PubMed1997

Interleukin-4, interleukin-10, and soluble tumor necrosis factor receptors in cord blood.

OBJECTIVE: We assessed cord blood for levels of interleukin-4 (IL-4), interleukin-10 (IL-10), and p55 (sTNFR-I) and p75 (sTNFR-II) soluble tumor necrosis factor receptors. STUDY DESIGN: Umbilical cord IL-4, IL-10, tumor necrosis factor alpha (TNF alpha), sTNFR-I, and sTNFR-II were measured in 21 normal appropriately grown newborns delivered vaginally (normal pregnancy), and 3 abnormal pregnancies (1 preterm delivery, 1 premature rupture of membranes with chorioamnionitis, and 1 abruptio placentae with fetal and neonatal distress). Umbilical cord arterial blood pH and PO2 were also measured. RESULTS: The TNF alpha, sTNFR-I, and sTNFR-II were detectable in all cord blood samples in normal pregnancies. IL-4 was detected in 10 of 21 samples (47.6%), and IL-10 was undetectable in normal pregnancies. IL-10 could be detected in the cases with chorioamnionitis and abruptio placentae. Soluble tumor necrosis factor receptors in the case with preterm delivery and the case with abruptio placentae were elevated compared with the levels in control samples. CONCLUSION: Both the p55 and p75 soluble tumor necrosis factor receptors are physiologic constituents of term cord blood. An immunosuppressive role of IL-10 and a protective role of soluble tumor necrosis factor receptors are suggested in abnormal pregnancies. However, in view of the small number of abnormal pregnancies, these observations must be considered preliminary.

Abruptio Placentae↗
PubMed1997

Antenatal diagnosis of aberrant umbilical vessels.

OBJECTIVE: To evaluate the antenatal screening of aberrant umbilical vessels and assess the association of fetal abnormality with these entities. STUDY DESIGN: 444 pregnant women were studied with routine obstetric ultrasound and Doppler color flow imaging in late second trimester or early third trimester. Fetal growth and anomaly, and the number of umbilical cord vessels were screened. RESULTS: Out of 444 subjects, 3 cases with discordant umbilical artery, 2 with four vessels in the umbilical cord, and 1 with single umbilical artery were detected (1.4%). Fetal anomaly was noted in 2 of 6 cases with aberrant umbilical vessels (33.3%). CONCLUSION: These results suggest that antenatal screening of umbilical cord vessels is necessary for detection of fetal anomalies.

Congenital Abnormalities↗
PubMed1997

Axonal pathology in Japanese Guillain-Barré syndrome: a study of 15 autopsied cases.

We assessed the frequency and extent of axonal involvement in the ventral spinal roots in 15 Japanese autopsied patients with Guillain-Barré syndrome (GBS). Teased-fiber preparation revealed that five had predominantly axonal pathology with minimal segmental demyelination, seven had predominantly segmental demyelination with minimal axonal changes, two patients showed a mixture of both conditions, and one patient did not show any particular pathologic changes. We confirmed axon loss by immunohistochemical analysis of high-molecular-weight neurofilament protein. Macrophage invasion was a prominent feature in nerves with predominantly axonal changes. Two patients with severe axonal involvement and prolonged clinical courses exhibited motor neuron loss with astrogliosis in the ventral horns. These results suggest that autopsy-verified axonal involvement is more frequent among Japanese GBS patients than in Caucasian populations but less frequent than that reported from northern China.

Adult↗
PubMed1997

[Research and development of beraprost sodium, a new stable PGI2 analogue].

A novel prostaglandin I2 (PGI2) analogue, beraprost sodium, is the first launched drug as an orally active PGI2. PGI2 was discovered in 1976, and has attracted much attention as a medicine for cardiovascular diseases such as strokes and heart attacks because of its potent antiplatelet and vasodilating effect. However, PGI2 is extremely unstable for the use as practical medicines. Thus, stable PGI2 analogues have been explored by a large number of researchers in the world. Just after the discovery of PGI2, we started a research on chemically and metabolically stable PGI2 derivatives with longer duration of action and less adverse reaction. We invented a novel class of stable PGI2, 5,6,7-trinor-4,8-inter-m-phenylenePGI2 analogues that have the phenol moiety instead of the enolether moiety of PGI2. Further efforts were devoted to enhance the efficacy of the PGI2 analogues and to eliminate their side effects, and an orally active analogue, beraprost sodium, was obtained. In order to establish the synthetic route of beraprost sodium, various novel processes were invented, including ortho-selective metalation of bromoanisoles by means of Grignard reagents, copper-catalyzed SN2' cyclization to prepare cyclopenta[b]benzofuran, and stereo-selective elongation of the omega-side chain by Prins reaction. Beraprost sodium inhibit platelet aggregation induced by adenosine 5'-diphosphate (ADP), collagen and arachidonic acid. It was shown that the drug has a potent antiplatelet effect both in vitro and ex vivo in human and several animal species. In clinical studies, beraprost sodium exerted a marked effect to improve arteriosclerosis obliterans. No serious adverse effects related with the drug have been reported. It was highly evaluated as an orally active PGI2 by pharmaceutical companies overseas as well, and now clinical trials are under way in U.S.A. and Europe.

Animals↗
PubMed1997

Iodine-123-BMIPP myocardial washout and cardiac work during exercise in normal and ischemic hearts.

UNLABELLED: Iodine-123-BMIPP washout at rest and after exercise was investigated in relation to cardiac work in normal and ischemic myocardium. METHODS: Sixteen healthy volunteers and 10 patients with ischemic heart disease were examined. After injection of 111 MBq of 123I-BMIPP, successive SPECT imaging was performed to evaluate washout ratio (WR) at rest and after mild and maximal exercise. RESULTS: In the healthy volunteers, the mean WR was 3.3 +/- 3.5% after 1 hr of rest and increased during both mild and maximal exercise. The WR showed a better correlation with net pressure rate product (PRP) than with the peak PRP. After maximal exercise, the WR showed a distinct correlation with the net PRP in the range from 200-300 x 10(3) mmHg/min and then showed a plateau greater than 10%. In five ischemic heart disease patients with the net PRP > or = 300 x 10(3) mmHg/min, the exercise WR values were significantly elevated in normal segments relative to ischemic segments. CONCLUSION: BMIPP washout increased with the increase in cardiac work during exercise in normal myocardium but not in ischemic myocardium. A certain amount of exercise is necessary to evaluate fatty acid metabolism in normal and ischemic myocardium.

Adult↗
PubMed1997

[Interstitial pneumonia in an HTLV-I carrier].

A 31-year-old woman was admitted to our hospital because of dyspnea on exertion. She had had the same symptom a few years earlier. A chest radiograph revealed ground-glass-like shadows on both sides, and the arterial PaO2 was 54 Torr when the patient was breathing room air. We first suspected hypersensitivity pneumonitis, but the dyspnea and hypoxemia did not resolve during treatment in the hospital, and returned home. She felt no obvious changes in symptoms while at home. We found no antibodies to Tricosporon cutaneum in her serum. Computed tomography of the chest revealed diffuse pan-lobular areas of high density. Bronchoalveolar lavage was done and the total cell count was 9.6 X 10(7). About three quarters (73%) of the recovered cells were lymphocytes. Examination of a transbronchial biopsy specimen showed alveolar thickening with infiltration of small mononuclear cells. No granulomas or Massons bodies were seen, and no antibodies specific to collagen-vascular disease were detected. We therefore excluded the diagnosis of hypersensitivity pneumonitis, idiopathic interstitial pneumonia and collagen-associated pneumonitis. There was no evidence of drug-induced pneumonitis. She was seropositive for HTLV-I. We suspected that this was a case of HTLV-1-associated pneumonitis.

Adult↗
PubMed1997

[Diffuse bronchiolo-alveolar cell carcinoma that produced both amylase and CA19-9].

A 68-year-old man who worked as an editor was admitted to Aichi Medical University Hospital due to dyspnea on exertion and emaciation. The patient had noticed rapid weight loss during diet therapy for diabetes mellitus that started in the beginning of July, 1993. Laboratory examinations revealed elevated levels of LDH and amylase in serum. Ultrasonography disclosed minimal ascites. Dyspnea on exertion developed in September, 1993. Chest roentgenography showed diffuse bilateral small nodular or reticular opacities. CT-guided percutaneous needle aspiration was done and cytologic examination of a specimen of lung tissue revealed papillary adenocarcinoma. The diagnosis was bronchiolo-alveolar carcinoma. Serum levels of amylase were elevated. The amylase isozyme pattern was of the salivary type. Serum levels of CA19-9 and CEA were also elevated. The patient died of respiratory failure on December 4, 1993. Postmortem examination revealed diffuse small nodules in both lungs. Examination of the nodules showed bronchiolo-alveolar cell carcinoma. The tumor cells stained positively for amylase (salivary type, not pancreatic type) CA19-9, and CEA by the avidin biotin complex method, but they were immunohistologically negative for AFP. We conclude that this lung cancer produced amylase, CA19-9, and CEA. We know of only a few reports of cases in which lung cancer produced both amylase and CA19-9.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed1997

The heterogeneous expression of CD80, CD86 and other adhesion molecules on leukemia and lymphoma cells and their induction by interferon.

CD80 (B7/BB-1, B7-1) and CD86 (B70, B7-2) take an important role in the interaction between T lymphocytes and antigen presenting cells (APCs) as co-stimulatory molecules. We analyzed the manifestation of adhesion molecules, including CD80 and CD86, on some leukemia and lymphoma cells. Constitutive expression of CD80 and/or CD86 was frequently observed on B cell leukemia/lymphoma cells, while it is rare on myeloid leukemia cells. Interferon-alpha (IFN-alpha) amplified the manifestation of MHC class I and interferon-gamma (IFN-gamma) did both class I and class II. We also showed CD80 could be induced by IFN-alpha on K562 cells, which were originally negative for CD80. Our data implies the immunotherapy via CD80 and CD86 for patients with hematological malignancies and the possibility to enhance it using interferons.

Antigens, CD↗
PubMed1997

[An autopsy case of severe tuberculosis associated with anal fistula and intestinal perforation].

A 55 year-old man was admitted to the department of the gastroenterology of the hospital because of severe weakness and appetite loss for the past one month. In the last two months, he has been suffering from recurrent fistula of the anus. He left his symptoms without therapy. A gastric ulcer was found out with gastric endoscopy. At the same time, chest X-ray film showed bilateral abnormal shadows, which were suspected of severe pulmonary tuberculosis by a chest physician. After the admission, the patient immediately developed respiratory failure. Both sputa and discharge from anal fistula were positive for acid fast bacillus. Despite of anti-tuberculosis therapy and mechanical ventilation, he died of respiratory failure. At the autopsy, severe pulmonary tuberculosis, tuberculous fistula of the anus, intestinal tuberculosis with perforation, miliary tuberculosis and peptic ulcer of the stomach were defined. We suspected that the extensive disease caused by hematogeneous spread and the late diagnosis of tuberculosis was owing to patient's delay.

Fatal Outcome↗
PubMed1997

[Relationship between iodine-123-beta-methyl-p-iodophenyl-pentadecanoic acid washout ratio and oxygen consumption in normal and ischemic myocardium].

The relationship between oxygen consumption and iodine-123-beta-methyl-p-iodophenyl-pentadecanoic acid (123I-BMIPP) washout at rest and after exercise was investigated in normal and ischemic myocardium. Sixteen healthy volunteers and 14 patients with ischemic heart disease were examined. After injection of 111MBq of 123I-BMIPP, serial single photon emission computed tomography imaging was performed to evaluate washout ratio after 30 min and 1 hour of rest and after exercise. In the volunteers, the mean washout ratio was 3.3 +/- 3.5% after 1 hour of rest and increased during exercise. The exercise washout ratio showed a better correlation with net pressure rate product (net PRP: cumulative values of PRP during exercise) than with the peak PRP. The exercise washout ratio showed a strong correlation with the net PRP in the range from 180 to 300 x 10(3) mmHg. beat/min and a plateau of 10-15%. In the nine ischemic patients with net PRP > or = 300 x 10(3) mmHg.beat/min, the exercise washout ratio values were significantly elevated in normal segments relative to ischemic segments (10.1 +/- 1.9% vs 4.7 +/- 2.9%, p < 0.001). In the five ischemic patients with net PRP < 300 x 10(3) mmHg.beat/min, washout ratio at rest and after exercise did not differ significantly between normal and ischemic segments. 123I-BMIPP washout ratio increased with increased oxygen consumption during exercise in normal myocardium but not in ischemic myocardium. The patient must exercise before fatty acid metabolism can be compared between normal and ischemic myocardium.

Adult↗
PubMed1997

[Active MR tracking system at 0.2T MR, a preliminary report: real time position tracking on interventional MR].

An active MR tracking system was installed in a 0.2 T open-type MRI. Interventional devices with a receive-only microcoil at their tips were newly developed for tracking at 0.2T. The low signal-to-noise ratio at 0.2T required the microcoils to have a diameter of about 2 mm and 20 turns for stable tracking. Simulation of MR-guided biopsy using biplane images with tracking in the gelatin phantom was performed. MR tracking in the aorta and IVC of a dog by a catheter with a microcoil at its tip was successful.

Animals↗
PubMed1997

[Bufferin-induced lung injury manifesting as acute eosinophilic pneumonia].

A 26-year-old woman was admitted to our hospital because of dyspnea and fever one day after taking medicines for the common cold. A chest roentgenogram and a computed tomogram revealed diffuse patchy infiltrates in both lung fields. Examination of a specimen obtained by transbronchial lung biopsy showed thickening of alveolar walls and infiltration of eosinophils. Bronchoalveolar lavage fluid had many eosinophils. DLST was positive for Bufferin, which the patient took one day before the dyspnea and fever began. We believe that this patient's pulmonary disease was caused by Bufferin. We should realize that this widely used analgesic can cause acute eosinophilic lung disease. The patient was not given corticosteroids, and her condition improved soon after she stopped taking Bufferin.

Adult↗
PubMed1997

[A case of humidifier lung characterized by histopathologic feature].

A 61-year-old man was discharged from our hospital after recovering from bilateral fractures in the neck of each femur. However, a productive cough, dyspnea, and a high grade fever occurred eight hours after returning home. He was thus admitted once more. At rehospitalization, there was radiographic evidence of bilateral infiltrates and hypoxemia. Hypersensitivity pneumonitis was strongly suggested by radiographic evidence, by the fact that no new drugs had been administered, and by a positive result after an environmental provocation test. A diagnosis of humidifier lung was confirmed by a positive precipitins test for humidifier water. Several microorganisms were isolated from humidifier water, and precipitins tests for the isolated microorganisms were mostly positive. Microscopic examination revealed focal alveolitis, bronchiolitis, and perivasculitis. Perivascular leucocytic infiltrations around venules suggested that inhaled antigens might have also caused humidifier lung via a vascular route. Humidifier lung may be due in part to soluble factors, such as endotoxin, present in humidifier water.

Alveolitis, Extrinsic Allergic↗