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Biomedical subjects

Y Seki

Publications and source records attributed to Y Seki.

At least 145 records · Page 8Linked to original sources
PubMed1990

Uptake of lead by human red blood cells and intracellular distribution.

Lead added to plasma was rapidly incorporated into suspended human red blood cells at 37 degrees C. The rate of lead uptake into the cells reached a maximum of 35 micrograms (0.17 mumole)/10(10) cells/h. The rate of lead uptake with resealed ghosts was comparable to that of intact cells. These findings indicate that the transport of lead across the erythrocyte membrane is, energy-independent, carrier-mediated passive transport, which confirms the conclusion of Simons. On the other hand, little release of incorporated lead from the cells in lead-free plasma was observed. Some 98% of intracellular lead was in cytoplasm, mostly in protein-bound form, and only 2% was in the membrane fraction. When red blood cells were incubated in plasma containing lead at about 10 mg/dl concentration for 24 hours at 37 degrees C, no progressive accumulation of lead and protein in the membrane fraction was observed. Thus, lead-protein complexes in cytosol are unlikely to associate with membranes. Human haemoglobin had forty-five binding sites for lead with the dissociation constant of 0.5 x 10(-6) M. The binding of lead to oxyhaemoglobin did not show any effect on the iron atom in the heme.

Binding Sites↗
PubMed1990

[Two cases of brain infarction associated with hypertriglyceridemia].

We reported two cases of brain infarction. They were cousins. Case 1 was a 12-year-old girl, who complained of aphasia, dyscalculia, right-left disorientation and right homonymous hemianopsia. CT showed low density areas in left superior and middle temporal gyri. Case 2 was a 15-year-old boy, who had left hemiplegia and hypesthesia to pain, temperature and touch on the left side of the body. CT showed low density areas from the genu of the internal capsule to the corona radiata, and from the posterior portion of putamen to the posterior limb of the internal capsule on the right side. Both cases had hypertriglyceridemia which might be associated with the etiology of infarction.

Adolescent↗
PubMed1989

Rubredoxin from Clostridium perfringens: complete amino acid sequence and participation in nitrate reduction.

The complete primary structure of rubredoxin (Rd) isolated from Clostridium perfringens was sequenced to be: MKKFICDVCGYIYDPAVGDPDNGVEPGTEFKDIPDDWVCPLCGVDKSQFSETEE. The sequence was highly homologous to that of C. pasteurianum Rd but was different at 13 sites out of the total 54 amino acid residues (76% homology). It contained 1 Fe atom, 4 cysteine residues, and no labile sulfur, had a molecular weight of 6,056, and shared the general properties of classical anaerobic Rds. The pI was 4.4. The Rd was reduced with NADH in the presence of a specific NAD(P)H oxidoreductase preparation from the bacterium. The Km value of nitrate reductase for Rd as an electron-donor was 12 microM, a value comparable to that of the 13 microM for ferredoxin (Fd). These results taken together provide additional support for its role as the electron carrier in the nitrate reductase system [Seki, S., Ikeda, A., and Ishimoto, M. (1988) J. Biochem. 103, 583-584].

Amino Acid Sequence↗
PubMed1989

Late onset erythropoietic porphyria.

A 51-year-old Japanese man and his 56-year-old sister of consanguineous parents had skin lesions with areas of dark-brown pigmentation and blisters with minimal trauma on sun-exposed skin which resembled those seen in porphyria cutanea tarda. Their fresh urine was wine-red in colour and fluoresced with ultraviolet light. The peripheral blood contained fluorocytes and porphyrin analysis of the red blood cells, urine and faeces of the patients revealed an increase of the isotype I of uro- and coproporphyrin and normal concentrations of delta-aminolaevulinate and porphobilinogen, suggesting the diagnosis of erythropoietic porphyria. No other members of this family had symptoms or biochemical findings suggestive of porphyria. We consider these two cases to be that of late onset erythropoietic porphyria.

Erythropoiesis↗
PubMed1989

Pemphigoid vegetans.

A Japanese case of pemphigoid vegetans is described. The clinical, histopathological and immunological features were similar to the previously reported cases. The patient also developed vesicular lesions. Indirect immunoelectronmicroscopy revealed that the autoantibody in this patient's serum reacted with basal cell hemidesmosomes. This study provides further evidence that pemphigoid vegetans is a subtype of bullous pemphigoid.

Aged↗
PubMed1989

[Determination of bromide ions in total blood, plasma and urine by ion chromatography with amperometric detection].

A direct injection method is described for the determination of bromide ions in plasma and urine by ion chromatography. After being diluted 10-20 times with eluent, the sample was directly injected into an ion chromatograph equipped with amperometric detection. Calibration curves were obtained in the range of 0.05 to 5 micrograms/ml of bromide ions. The coefficient of variation was calculated to be in the range of 1.3-9.4% for 10 repeated measurements and recovery was over 93%. The correlation between analytical results by the proposed method (Y) and those by a spectrophotometric method (X) of 169 urine samples in fumigators was expressed by the equation Y = 0.952 + 1.012X (correlation coefficient (r): 0.952). On the other hand, the correlation between analytical results by the proposed method (Y) and those by neutron activation analysis (X) of 47 total-blood samples in fumigators was expressed by the equation Y = 1.070 + 0.841 X (correlation coefficient (r): 0.931). The correlation between analytical results by the proposed method (Y) and those by neutron activation analysis (X) of 40 plasma samples in healthy workers was expressed by the equation Y = 0.633 + 0.871 X (correlation coefficient (r): 0.955). The proposed method is much more practical than other methods such as the spectrophotometric method and neutron activation analysis in epidemiological studies, because the proposed method is highly accurate and reproducible over longer periods. The proposed method is useful in biological fluid monitoring of bromide ions.

Bromine↗
PubMed1989

Efficiency of respirator canisters with methyl bromide.

Two kinds of respirator canisters, an organic vapor (OV) canister containing activated carbon and a methyl bromide (MB) canister containing activated carbon impregnated with triethylenediamine were investigated for their filtration efficiency of MB gas under various conditions of MB concentration, humidity and temperature. At lower MB concentrations, the breakthrough time of the OV canister was shorter than that of the MB canister. It also decreased with an increase in temperature, whereas the breakthrough time of the MB canister did not change with temperature. Humidity affected the breakthrough times of the OV canister as much as those of the MB canister. The desorption and the remaining filtration efficiency of MB gas were examined in both canisters which had been used for fumigation in plant quarantine. More than 5 ppm of MB gas leaked from 11 out of 18 used OV canisters, whereas less than 0.1 ppm MB leaked out from each of the used MB canisters. The mean remaining breakthrough time of the used OV canisters was 9.3 min, whereas that of the used MB canisters was 74.4 min. From the present study, it was shown that the gas masks with the OV canisters were not suitable for fumigating with MB gas.

Evaluation Studies as Topic↗
PubMed1989

[Clinical use of castable ceramics (OCC) crown].

The new ceramics material (OCC) was developed for the purpose of aesthetic restration which can be fabricated by an usual lost wax process and it produces accurate marginal fit. OCC possesses mechanical, chemical, and physical properties. This article is discussed utility and security of OCC complete crown on the clinical application from Dec, 1986 to Jun, 1989. The results may be summarized as follows: 1) 2 of 69 cases were broken down in the period from Dec, 1986 to Jun, 1989. These reasons are caused by the lack of occlusal thickness and unsuitable fit of crown. 2) Although 4 of 69 cases are stained by tobacco tar and 5 of 69 cases are suffered from plaque accumulation, these staining and plaque accumulation are improved by plaque control. 3) An allergic reaction or an abnormality of oral tissues haven't been recognized during test period of clinical use. Consequently OCC crown showed itself about safety and usefulness.

Crowns↗
PubMed1989

[A case of unilateral masticatory spasm without hemifacial atrophy].

Masticatory spasm is a rare clinical feature and mostly associated with disorders of general movement. Usually it occurs bilaterally. Unilateral masticatory spasm is mostly associated with facial hemiatrophy. So, unilateral masticatory spasm without facial hemiatrophy is extremely rare. As far as we have investigated, only one case has been reported in the literature. We will report one more case herein, with some discussion on its pathogenesis. Case report A 44-year-old man presented with a 8 month history of slowly progressive recurrent spasm of the left masseter muscle. The spasm was exaggerated by tension and lasted for up to 10 seconds. Several drugs could not reduce the frequency of spasm, but only clonazepam could decrease it slightly. On admission, the spasm lasted usually for 1 or 2 seconds. Except for masticatory spasm, neurological examination comprising trigeminal nerve function, was normal and facial atrophy was not observed. On the contrary, hypertrophy of the left masseter muscle was noted. Needle electromyography (EMG) study revealed synchronized spasm discharges of the ipsilateral masseter, lateral and medial pterygoid muscles. All of other investigations, including CSF analysis, electroencephalography, somatosensory evoked potential, visual evoked potential, CT scan and vertebral angiography, showed normal findings. After all, we could not find any apparent organic lesions which cause masticatory spasm, so surgical treatments were not carried out. He was discharged and now, continues to take clonazepam daily.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[Superselective bronchial arterial catheterization via a sheath catheter (SS-BAC)].

Bronchial artery infusion therapy including embolization of the artery has been widely used in the treatment of lung cancer and also for the treatment of hemoptysis due to various lung diseases. However, some serious complications such as spinal cord lesion, tracheobronchial fistula formation and so on have been documented in the literature and these complications are attributed to anatomical characteristics of the bronchial artery having a common trunk with feeding arteries to the spinal cord, esophagus and trachea. To prevent these hazardous events we attempted to infuse and embolize the proper bronchial artery with high selectivity by using catheter-in-catheter technique. A Cook green catheter, 7.2 Fr. size, was wedged in the intercostobronchial trunk artery by a Seldinger technique and then a small catheter, 3.0 Fr. size, was passes through the former catheter to the proper bronchial artery beyond the orifices of other feeding arteries. In 26 out of 30 patients who underwent this procedure we successfully performed this superselective bronchial artery catheterization and the 26 patients consisted of 15 patients with lung cancer and one with metastatic lung tumor who were treated with bronchial artery infusion therapy and ten with various lung diseases who were treated with bronchial artery embolization because of hemoptysis. Bronchial artery infusion therapy including embolization has gained higher safety and effectiveness by means of this superselective catheterization.

Adult↗
PubMed1989

[IBL-like T cell lymphoma associated with early gastric cancer: a case report].

A 67-year-old man was admitted in October 1987 with complaints of nausea, headache, dizziness and speech disturbance. Hematological examination showed pancytopenia. Bone marrow aspiration failed with a dry tap. A month later, the second aspiration showed hypocellular marrow containing 18.2% of lymphoma cells. Physical examination showed splenomegaly and lymph node swelling. Polyclonal hypergammaglobulinemia was not observed. A lymph node biopsy exhibited typical histology of immunoblastic lymphadenopathy (IBL)-like T cell lymphoma. Surface marker CD3 and CD4 positive cells were dominant. The patient complained of epigastric pain and occult blood was positive in stool. Gastrofiberscopic examination disclosed well differentiated adenocarcinoma in situ located on a polyp, and polypectomy was performed. Lymphoma was treated with cyclophosphamide, doxorubicin, vinblastine and prednisolone. Splenomegaly and lymph node swelling were reduced in size but the effect was temporary. Thereafter the patient has been treated with cyclophosphamide, doxorubicin, vindesine, prednisolone and etoposide every 3 weeks. This is our first case report of IBL-like T cell lymphoma associated with early gastric cancer.

Adenocarcinoma↗
PubMed1989

[Benign superior vena cava syndrome associated with Horner syndrome--report of a case].

Superior vena cava syndrome is commonly caused by malignant diseases such as lung cancer, malignant lymphoma and so forth. It is uncommon that benign diseases obstruct the superior vena cava or its major tributaries. But there are some documented cases of benign superior vena cava syndrome induced by mediastinitis, benign mediastinal tumors, and uncommon lesions having their primary origin in the mediastinum. A 41-year-old male patient had recognized his ptotic palpebra two years ago and chest roentgenographic examination disclosed a tumor shadow occupying the apex of the right thorax but he was almost asymptomatic except venous dilatation of the anterior chest wall. Venography revealed obstruction of the brachiocephalic vein and superior vena cava. At thoracotomy the tumor was found to be impacted at the apex of the thoracic fornix and to be cystic. Primary site of the tumor was at the chest wall and its histological finding was compatible with that of neurilemmoma. Postoperative venography confirmed complete patency of the brachiocephalic vein and superior vena cava.

Adult↗
PubMed1988

Melanosomal alterations in dysplastic melanocytic nevi. A quantitative, ultrastructural investigation.

Abnormal-looking melanosomes are observed commonly in both intraepidermal melanocytes of cutaneous melanoma and dysplastic melanocytic nevi (DMN). This was investigated by using transmission electron microscopic examination to determine the percentage of abnormal melanosomes among 8267 melanosomes assessed in at least five solitary intraepidermal basal unit melanocytes from each of five specimens of DMN, superficial spreading melanoma (SSM), common acquired nevomelanocytic nevi (NMN), and normal skin (NS) adjacent to DMN. The percentage of abnormal melanosomes in DMN (mean + SD, 44 + 23%) was seven times greater than that in NMN (6 + 7%) and 22 times greater than that in NS (2 + 5% [P less than 0.001, both comparisons]), but only 80% that in SSM (57 + 19% [P less than 0.02]). Melanocyte area, nuclear area, and the ratio of nuclear area to cytoplasmic area did not account for the observed differences. Melanosomal alterations may be a useful marker of atypicality in melanocytic tumors.

Adult↗
PubMed1988

Intraoperative identification of the central sulcus: a practical method.

A practical method of intraoperative identification of the central sulcus using cortical evoked potentials (EP) was reported. The method herein proposed is unique with stimulation to the trigeminal and tibial nerve in addition to median nerve stimulation, depending on the location of the lesion. Thus, a wide coverage of the rolandic fissure was possible. Eighteen adult patients with peri-rolandic lesions were investigated. Fourteen cases had a malignant tumour but all except 3 showed only a minor neurological deficit preoperatively. In 13 cases, the central sulcus could be identified through the phenomenon of the phase-reversal of cortical EP across the central fissure. Of the remaining 5 cases, cortical EP were not detected in 3 (all showed hemiplegia and/or aphasia) and EP without phase-reversal were obtained in 2. As a result, in most cases showing only a trivial neurological deficit before surgery, aggressive removal of the tumour was successfully carried out without producing severe motor dysfunction.

Adult↗