Search PubMed⌕ Search

Biomedical subjects

M Saeki

Publications and source records attributed to M Saeki.

At least 91 records · Page 5Linked to original sources
PubMed1994

Hereditary abnormality of luteinizing hormone resulting in discrepant serum concentrations determined by different assays.

We herein report familial defects in the molecular structure of luteinizing hormone (LH). The propositus was a 29-year-old women with repeated abortion in whom the serum LH concentration was extremely low determined by an immunoradiometric assay utilizing two monoclonal antibodies for the intact LH dimer and beta-subunit of LH (SPAC-S kit). Further studies on the serum LH concentration in this propositus by five different assay systems gave various results ranging from low to normal values. Bioassay of the propositus's LH using C57 black mice showed normal in biological activity. These data suggest that LH in the propositus is abnormal in terms of its molecular structure located in the bond region between alpha and beta subunits. A family study showed that the bioactivity of LH was normal in all family members. The serum LH was not detected in either the propositus or her brother with the SPAC-S kit even after the administration of LHRH, while the serum LH concentrations in the father, mother and sister were approximately half the normal range, indicating that the defect is hereditary and the mode of inheritance is autosomal dominant: the propositus and brother were homozygously affected, and the parents and sister heterozygously affected.

Abortion, Habitual↗
PubMed1994

Morphological analysis of multinucleated giant cells occurred in experimental autoimmune myocarditis.

Our previous study reported the rich existence of multinucleated giant cells in an autoimmune myocarditis experimentally induced in rats. The present study investigated the histochemical and ultrastructural characteristics of these giant cells. Histochemistry for an acid phosphatase clearly demonstrated multinucleated giant cells dispersed at the inflammatory foci. Ultrastructurally, the giant cells were shown to be single cells, but not clustered cells. Their ultrastructural characteristics were very similar to the basic features of macrophages, except that the giant cells were poor in lysosomes and phagosomes. It was noticeable that some macrophages possessed three or more nuclei, displaying an intermediate form between mononuclear macrophages and multinucleated giant cells. These findings suggest that the giant cell in the experimental autoimmune myocarditis is a single multinucleated cell, and possibly derived from macrophages by cell-to-cell fusion.

Acid Phosphatase↗
PubMed1993

[Biliary lithotripsy using super fine cholangioscopy with the deviced bended sheath].

Percutaneous transhepatic cholangioscopy (PTCS) is an useful technique to evaluate or treat biliary diseases, although PTCS is an invasive method for the patients. We used 5 F or 7 F of super fine cholangioscopy to treat two cases of choledocholithiasis after surgery without dilatation of drainage tract. We developed different types of bended sheath for supplement of lack of angle system in this cholangioscope. Furthermore, by using bended sheath, cholangioscopic view improved, because saline was injected at the same time via the sheath. We emphasize that super fine cholangioscope with bended sheath is a safe and useful modality for evaluation of biliary disease.

Adult↗
PubMed1993

Cardiac contractile proteins and autoimmune myocarditis.

Concerning cardiac contractile proteins, antigenicity and myocardiotogenicity were discussed. In normal states, these proteins are immunologically tolerant, and can not provoke any heart-specific disease. Why the proteins can provoke such lethal autoimmune myocarditis has not been completely elucidated. Shortly after cardiac infection or myocardial ischemia, these proteins may work as the antigen for the autoimmune myocarditis. First of all, the role of cardiac myosin has been strongly emphasized. But, the antigen determinants: epitope proteins remain unclear. Either cross-activity to the streptococcal M protein and/or the alpha-helical coiled-coil protein may be an important factor to determine antigenicity. In this autoimmune myocarditis, the roles of T-lymphocyte and cardiac dendritic cell are noticeable. Through further study on the relation between antigen epitope and the infectious agents in the heart; on cardio-cytotoxicity of the T-lymphocyte and on the precise contribution of cardiac dendritic cells, this autoimmune myocarditis will be more clarified.

Actins↗
PubMed1993

FK506 therapy of experimental autoimmune myocarditis after onset of the disease.

Preventive effects of FK506 on autoimmune myocarditis have been demonstrated, but the therapeutic efficacy of the agent in established myocarditis yet remains to be assessed. In this study, effects of FK506 on experimental autoimmune myocarditis were investigated by the use of the agent after the onset of the disease. Lewis rats were immunized with either cardiac myosin or bovine serum albumin (BSA) in complete Freund's adjuvant. The onset of the disease was ascertained by examining randomly chosen cardiac myosin-immunized rats. Animals were divided into four groups: the BSA-immunized saline-treated group (group A, n = 6); the BSA-immunized FK506-treated group (group B, n = 6); the myosin-immunized saline-treated group (group C, n = 6); and the myosin-immunized FK506-treated group (group D, n = 11). Saline or 1.0 mg/kg/day of FK506 were intramuscularly injected from day 16 to day 27. All the rats were put to death on day 28. Rats of group C became severely ill by the third week, while in contrast, rats of group D remained active, as did rats of groups A and B. The heart weight/body weight ratio was significantly lower in group D than in group C rats. Group mean values were 3.48 +/- 0.10 gm/kg for group A, 3.48 +/- 0.16 gm/kg for group B, 4.94 +/- 0.66 gm/kg for group C, and 3.88 +/- 0.43 gm/kg for group D. Rats of group C showed severe myocarditis with mononuclear cell infiltration, myocardial necrosis, and interstitial edema.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Effect of dietary hydrogenated corn oil (trans-octadecenoate rich oil) on plasma and hepatic cholesterol metabolism in the hamster.

The effect of dietary hydrogenated corn oil (trans-octadecenoate-rich oil) on plasma cholesterol and triglyceride concentrations was compared with dietary palmitic acid in hamsters given a cholesterol-rich diet. The addition of dietary palmitic acid and hydrogenated corn oil accelerated the increase in plasma VLDL- and LDL-cholesterol levels and plasma triglyceride level induced by dietary cholesterol loading. Dietary cholesterol, palmitic acid and hydrogenated corn oil showed no effect on plasma HDL-cholesterol concentration. A decrease in hepatic LDL receptor activity was seen in animals fed a diet supplemented with cholesterol in combination with palmitic acid or hydrogenated corn oil in comparison with animals fed a diet supplemented with cholesterol alone. Hydrogenated corn oil (trans-octadecenoate-rich oil) appears to potentiate the effect of dietary cholesterol in elevating the plasma VLDL- and LDL-cholesterol levels through the suppression of hepatic LDL receptor activity. trans-Octadecenoate in dietary hydrogenated corn oil may be as atherogenic as dietary palmitic acid due to a suppression of hepatic LDL receptors in the presence of dietary cholesterol loading.

Animals↗
PubMed1993

Identification of a functional receptor differing from the LDL receptor that catabolizes chylomicron remnant in Hep G2 cells.

We investigated types of lipoprotein receptors on Hep G2 cells using a monoclonal antibody against the LDL receptor. IgG-C7 inhibited the binding and internalization of 125I-labeled low density lipoprotein (LDL) in Hep G2 cells with upregulated and downregulated LDL receptors by 90% of control values. Binding and internalization of 125I-labeled chylomicron remnant in Hep G2 cells with upregulated and downregulated LDL receptors was 50% and 85%, respectively, of control values after exposure to IgG-C7. Excess unlabeled chylomicron remnant inhibited binding and internalization of 125I-labeled chylomicron remnant in Hep G2 cells with downregulated LDL receptors completely. Pronase treatment abolished binding and internalization of 125I-labeled LDL and 125I-labeled chylomicron remnant in Hep G2 cells. When solubilized fractions of Hep G2 cells were immunoprecipitated with IgG-C7, the binding activity of 125I-labeled chylomicron remnant to reconstituted vesicles was unchanged. 45Ca blotting analysis showed the presence of 45Ca binding protein (approximately 600 kDa) in Hep G2 cells. The amount of 45Ca binding protein was not affected by cholesterol and was abolished by pronase treatment. These results suggest the existence of a functional receptor other than the LDL receptor that catabolizes chylomicron remnant in Hep G2 cells and that this receptor may correspond to LDL receptor-related protein.

Antibodies, Monoclonal↗
PubMed1993

Sacroperineal anorectoplasty using intraoperative ultrasonography: a preliminary report.

Intraoperative ultrasonography (US) was applied to sacroperineal anorectoplasty for the purpose of making a pull-through tunnel under visual guidance. Intraoperative US images the horizontal plane of the muscle complex and the tip of the forceps, which is placed at the entrance of the tunnel (ie, the space anterior to the puborectalis sling), ready to penetrate the muscle complex. A surgeon can thus penetrate the center of the muscle by confirming the relation between the muscle and forceps on the US screen. Postoperative computed tomography of four patients on whom this technique was applied demonstrated that the rectum was pulled through the exact center of the puborectalis and external sphincter muscles.

Anal Canal↗
PubMed1993

Partial cloning of cDNA for hamster liver cholesterol 7 alpha-hydroxylase.

A partial cDNA clone encoding cholesterol 7 alpha-hydroxylase (pHA 7 alpha-3) was isolated from a hamster liver cDNA library using rat P-450 ch7 cDNA (p 7 alpha-11) as a probe. In comparison with the complete base sequence of p 7 alpha-11, pHA 7 alpha-3 lacked about 500 base pairs at the 5' end. Circadian rhythms of mRNA for hamster liver 3-hydroxy-3-methylglutaryl coenzyme A reductase and cholesterol 7 alpha-hydroxylase were investigated with cDNA clones encoding 3-hydroxy-3-methylglutaryl coenzyme A reductase (pRed-227) and pHA 7 alpha-3. Typical circadian rhythms of mRNA for both enzymes and a time lag between the two circadian rhythms were observed. The circadian rhythm of activity for each enzyme corresponded to that of each mRNA.

Animals↗
PubMed1993

Electrical resonance of isolated hair cells does not account for acoustic tuning in the free-standing region of the alligator lizard's cochlea.

The cochlea of the alligator lizard is divided into two morphologically and physiologically distinct regions. In the "tectorial region," hair bundles of hair cells are draped by a tectorial membrane, whereas in the "free-standing region," hair bundles are said to be free-standing because there are no overlying tectorial structures. The acoustic tuning of the free-standing region depends at least in part on mechanical resonances of the hair bundles. In the turtle cochlea, in contrast, acoustic tuning depends in large part upon the electrical properties of the hair cells. We have investigated the electrical properties of hair cells isolated from the free-standing region of the alligator lizard's cochlea. When injected with steps of depolarizing current, these "free-standing hair cells" exhibited electrical resonances that were comparable in frequency and quality to electrical resonances in cochlear hair cells from turtles, chicks, and alligators, and in saccular hair cells from frogs and fish. In the lizard's free-standing hair cells, however, the electrical resonance frequencies (< 300 Hz) were a decade below the cells' acoustic characteristic frequencies (between 1 and 4 kHz), showing that the electrical resonance is not likely to contribute to acoustic tuning. The electrical resonances were not apparent at rest. The cells' resting potentials were significantly more negative than the activation voltage (approximately -40 mV) of the Ca(2+)-dependent K+ current upon which the electrical resonance has been shown to depend in other hair cells. At potentials more negative than -50 mV, an inwardly rectifying K+ conductance dominated. Because we observed no electrical tuning above 300 Hz, our results indirectly support a mechanical origin for acoustic tuning in the free-standing region of the alligator lizard cochlea. These results further show that acoustic tuning cannot be inferred solely from the electrical resonances of isolated hair cells.

Animals↗
PubMed1992

[Clinical application of 31P MRS to malignant liver tumors--with an emphasis on evaluation of response to therapy].

Malignant liver tumors in 19 cases (13 hepatomas and 6 metastatic tumors) were studied by 31P magnetic resonance (MR) spectroscopy. Five healthy volunteers were also studied. Volume localization was performed using the ISIS sequence. Compared with normal liver, the MR spectra of malignant tumors showed an elevated phosphomonoester (PME) peak relative to beta ATP (p less than 0.005), and tumors were slightly alkaline (pH 7.32 +/- 0.08) before therapy. Nine cases of hepatomas responding to chemoembolization showed extremely reduced signal intensity of spectra. Tumor pH was compared before and after therapy in four cases that showed good response to therapy, and was elevated in all of them. Three metastatic tumors with good response showed reductions in PME and ATP after therapy. MR spectroscopy with adequate localization technique is useful in demonstrating the response of malignant tumors to therapy.

Carcinoma, Hepatocellular↗
PubMed1992

[Signal contamination problem in three-dimensional localization technique of MR spectroscopy--experiment and an analysis of patient data].

Signal contamination from the surrounding volume was studied using the ISIS sequence, a three-dimensional localization technique. In phantom experiments, contamination decreased with the increase of Tr, regardless of where the contamination originated from. In 52 localized liver spectra with a Tr of 2 sec, PCr contamination was estimated at 3 to 4%, and contamination of ATP signals from the surrounding liver tissue at less than 1%, because of the relatively short T1 of ATP in the liver. In the spectra of brain neoplasms obtained using the simultaneous double-volume selection technique, the PCr ratio in the tumor relative to the control area was high in low grade astrocytoma (0.80, n =8) and low in others (0.45, n = 11). Considering contamination and spectral noise, a PCr ratio of less than 0.4 does not strongly suggest the existence of PCr in tumors. Among 25 cases whose therapeutic processes were monitored by MRS, signal disappearance was observed in two cases in the localized spectra after therapy. In both of them, tumor necrosis was proved pathologically and correlated well with spectroscopic findings. It was found that the ISIS technique suppressed signal contamination to the level of several percents, providing spectra of acceptable quality through localization.

Humans↗
PubMed1992

Determination of pyrimethamine and sulphadimethoxine residues in eggs by high performance liquid chromatography.

1. Laying hens were given food containing per kg diet: 1 mg pyrimethamine, 10 mg sulphadimethoxine (SDM) or 1 mg pyrimethamine with 10 mg SDM, for 14 days. Residues in the eggs were determined by high performance liquid chromatography. 2. Pyrimethamine was mainly found in yolk. Its concentration was slightly higher when it was given with SDM. 3. The concentrations of SDM in eggs were not different when it was given alone or in combination with pyrimethamine. 4. After withdrawal, pyrimethamine residues decreased below the detection limit (0.02 mg/kg) in the yolk after 11 to 12 d and in the albumen after 2 to 3 d. SDM in yolk fell below the detection limit (0.01 mg/kg) on day 7, whereas in albumen it was not detectable after 2 to 3 d.

Animals↗
PubMed1992

What is the clinical disadvantage of discarding old radiographs? Survey of patients not re-examined for a long time.

The clinical disadvantage of discarding old radiographs was evaluated in patients who had not been re-examined for more than 8 years after their last radiological examination, 38,772 in total. During the 1 year survey, 158 (0.41%) of them underwent re-examination after a long interval. Retrospective evaluation revealed that in only 12 patients (0.032%) were the old films useful. This survey suggested that the clinical risk of not referring to films more than 8 years old would be less than 0.049%. We consider this acceptable, and have formulated new guidelines of storage of films.

Evaluation Studies as Topic↗
PubMed1992

[Surgical treatment of tracheobronchial lesions in children].

A total of 16 cases of tracheal and bronchial lesions such as bronchial tumor (4 cases), aspirated foreign body (5 cases), and tracheo-bronchial stenosis (7 cases) were surgically treated at the National Children's Hospital from 1965 to 1990. A mucoepidermoid tumor was excised via bronchotomy. Pulmonary lobectomy was indicated for another 2 mucoepidermoid tumors which arose from the middle and lower lobe bronchus. Pneumonectomy was indicated for a leiomyoma located at the stem of the left bronchus and showed extensive invasion into the bronchial wall. It is important to accurately diagnose the location and extent of the tumor by performing intraoperative bronchoscopy, bronchotomy, frozen section examination in order to avoid unnecessary pulmonary resection. Three aspirated foreign bodies (2 marking needles and a peanut) were removed via bronchotomy. Right lower lobectomy was performed in a patient who received an accidental injection of barium sulfate into the right lower bronchus. The barium remained for more than one year and caused recurrent pneumonia. A radiolucent toy plate aspirated into the left main bronchus of a 3-year-old girl was overlooked for more than 3 years. Suppurative changes of the left lung necessitated pneumonectomy. Tracheal resection with end-to-end anastomosis was carried out successfully in a 5-year-old patient suffering from segmental fibrogranulous stenosis of the mid-trachea. Extensive congenital stenosis in 6 patients was repaired by costal cartilage autograft, with a 67% mortality rate. Treatment of the associated cardiac anomalies and the possible postoperative complications such as anastomotic leakage, restenosis, exuberant granulation, and tracheomalacia are the major problems associated with this type of tracheoplasty.

Bronchi↗