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Biomedical subjects

K Seki

Publications and source records attributed to K Seki.

At least 19 recordsLinked to original sources
PubMed1992

Epoxyeicosatrienoic acid stimulates ADP-ribosylation of a 52 kDa protein in rat liver cytosol.

In rat liver cytosol, rapid ADP-ribosylation of a 52 kDa protein by endogenous ADP-ribosyltransferase(s) was observed. This ADP-ribosylation was stimulated dose-dependently by 14,15-epoxyeicosatrienoic acid (14,15-EET), one of the metabolites of arachidonic acid by NADPH-dependent cytochrome P-450 mono-oxygenase. This stimulatory effect required the presence of GTP or its non-hydrolysable analogues, guanosine 5'-[beta gamma-imido]triphosphate or guanosine 5'-[gamma-thio]triphosphate. Of four regioisomeric EETs, 14,15-EET was the most potent. No stimulatory effect was observed with addition of 14,15-dihydroxyeicosatrienoic acid, a stable metabolite of 14,15-EET. The 52 kDa protein was not ADP-ribosylated by cholera toxin A subunit and pertussis toxin, and was not recognized by anti-Gs alpha and anti-Gi alpha antibodies. However, the 52 kDa protein could be photoaffinity-labelled with 8-azidoguanosine 5'-[alpha-32P]triphosphate. These results suggest that the 52 kDa protein is neither Gs nor Gi, though it may have a GTP-binding site. These results contribute to the understanding of the role of mono-oxygenase metabolites of arachidonic acid in intracellular signal transduction.

8,11,14-Eicosatrienoic Acid↗
PubMed1992

Malignant peripheral nerve sheath tumors: an immunohistochemical study in relation to ultrastructural features.

The constituent cells in malignant peripheral nerve sheath tumors were examined by studying the expression of immunohistochemical markers for Schwann cells and perineurial cells in relation to ultrastructural features in 12 malignant peripheral nerve sheath tumors. Ultrastructural studies demonstrated mixed proliferation of Schwann cells, perineurial cells, fibroblastic cells, and primitive cells in many malignant peripheral nerve sheath tumors. Expression of S-100 protein was well correlated with Schwann cell-like differentiation of tumor cells. However, Leu-7 and epithelial membrane antigen, which have been considered to be specific to Schwann cells and perineurial cells, respectively, were common to Schwann cells, perineurial cells, and primitive cells. The common immunophenotypic expression suggests a close relationship among these cell types. The unusual expression of cytokeratin could be explained by the plasticity of intermediate filament expression.

Adult↗
PubMed1992

Prostaglandins and premenstrual syndrome.

We examined plasma PGF2 alpha, PGE, PGE2, TXB2 and 6-keto-PGF1 alpha at intervals throughout 3 menstrual cycles in 20 patients with PMS. Similar measurements throughout 1 menstrual cycle were made in 12 age-matched control women. The plasma concentration of PGF2 alpha in the late luteal phase was significantly lower in patients with PMS compared with that in the control subjects. The plasma concentrations of PGE in the middle follicular phase and middle luteal phase, PGE2 alpha in the middle follicular phase and TXB2 in the middle and late luteal phase were significantly higher in 20 patients compared with the values in the controls. A disturbance of PG metabolism may contribute to the etiology of PMS.

Adolescent↗
PubMed1992

Cutaneous leiomyosarcoma.

A child's head-sized tumor on the upper back developed in a 43-year-old man. In spite of an extensive operation for the tumor, he died of multiple metastasis 15 months after the operation. Histologically, tumor cells proliferated throughout the dermal and subcutaneous regions, and a boxed-in appearance was noted with silver staining. Because electron microscopic observations strongly suggested a smooth muscle origin, we diagnosed this case as cutaneous and subcutaneous leiomyosarcoma.

Adult↗
PubMed1992

Intracellular localization of Staphylococcus aureus within primary cultured mouse kidney cells.

Staphylococcus aureus Cowan I was incubated with monolayers of cells derived from several portions of mouse kidney, and found to be ingested by all types of the renal cells. Intracellular localization of S. aureus was determined by resistance of intracellular cocci against lysostaphin digestion and confirmed by electron microscopy. From renal medulla, three morphological variants of the hyperosmolarity-tolerant (HOT) cells were obtained. The rate of cocci-ingesting cells varied from 16.9% to 93.4% among these of the HOT cells at the end of 3-hr incubation. From renal cortex, three morphological variants of epithelial cells grew in medium RK-1. Among them, only the cells on the edge of colony ingested Cowan I, while the epithelial cells on the center of colony ingested few cocci. Transferred from medium RK-1 to MEM supplemented with 10% FBS, part of the cortical cells changed into fibroblast-like appearance and obtained the capacity to ingest Cowan I. This result may indicate the correlation between ingesting capacity and cellular morphology. From a glomerulus, epithelial (GE) cells and fibroblast-like (GF) cells were obtained. The GE cells ingested not only S. aureus Cowan I but Staphylococcus epidermidis and Staphylococcus saprophyticus after 30-min incubation, while the GF cells, like both of the HOT cells and the cortical cells, ingested only S. aureus. These results suggest a possibility that S. aureus is located within nonprofessional phagocytes during its infection and intracellular coccus plays an important role in its pathogenicity.

Animals↗
PubMed1992

Conspicuous ingestion of Staphylococcus aureus organisms by murine fibroblasts in vitro.

A conspicuous adhesion of Staphylococcus aureus organisms to murine cutaneous fibroblasts and NIH/3T3 cells cultured in vitro and subsequent ingestion of S. aureus organisms by these fibroblasts are described. In the present experimental system, only fibroblasts-adhering S. aureus organisms were efficiently ingested by fibroblasts unlike S. epidermidis and S. saprophyticus. These findings might suggest a correlation between the pathogenesis of S. aureus and its intracellular localization in non-professional phagocytes such as fibroblasts in a special reference to its higher pathogenicity than those of coagulase negative counterparts.

3T3 Cells↗
PubMed1992

Orthostatic tremor associated with voice tremor.

We report a 67-year-old female with orthostatic and voice tremor. Her orthostatic tremor mainly affected her lower extremities, alternating between antagonist muscle groups at a frequency of 4.4-4.8 Hz. The voice tremor ranged between 4.8 and 8.8 Hz. In this case, the frequency of voice tremor was same as that of orthostatic tremor, suggesting a common origin from a tremor-generating mechanism. These tremors were diagnosed as 'forme fruste' of the essential tremor, not the incipient stage of Parkinson's disease. Medications including clonazepam, perphenazine, Dopa and trihexyphenidyl hydrochloride had no effect on both the orthostatic and voice tremors, but propranolol was somewhat beneficial on voice tremor.

Aged↗
PubMed1992

Leiomyosarcoma of the uterus: ultrasonography and serum lactate dehydrogenase level.

Between January 1, 1979, and September 30, 1990, a total of 1,886 patients in the National Defense Medical College Hospital, a self-referred population, had a hysterectomy because of signs and symptoms presumably resulting from uterine myomas. After hysterectomy with presumed benign disease, a histologic diagnosis of leiomyosarcoma was made in 7 patients (0.37%). Preoperative diagnosis of leiomyosarcoma was not made in any of the 7 patients. However, serum lactate dehydrogenase levels were abnormally elevated in 3 of them, and degenerative changes were found within the tumor by ultrasonography in 5 of them. Furthermore, increased lactate dehydrogenase levels and degenerative changes within the tumor were found in 3 of the patients whose tumors had 10 or more mitoses per 10 high-power fields. The prognosis for the leiomyosarcomas with increased mitotic rates is very poor. Therefore, a degenerative change within the uterine mass and an increased lactate dehydrogenase level, when present, should suggest the diagnosis of leiomyosarcoma.

Adult↗
PubMed1992

Recovery of impaired motor function of the upper extremity after stroke.

Manual function score (MFS) of 174 hemiparetic stroke patients was examined every week for 8 weeks after starting the occupational therapy with programs based on MFS recovery profile, and the relation between the time since stroke onset (x) and MFS (y) was approximated by a hyperbolic function, y = A - B/x. The patients were classified into two groups, 125 cases (71.8%) with statistically significant fit of the function (fit group) and 49 without fit (non-fit). Using demographic and neurological variables of each patient, characteristics of the patients with regular recovery were analyzed. The results indicated that the gain of MFS during 8 weeks of the therapy was large in the fit group compared to the non-fit, and the regular recovery could be mostly expected in rather young patients, those with early start of the therapy, and those without ataxia, mental deterioration, and cortical lesions.

Arm↗
PubMed1992

Characteristics of physiological tremor in five fingers and evaluations of fatigue of fingers in typing.

Physiological tremor, which is the invisible mechanical vibration of body part, was measured for five fingers. It was obtained that the power spectrum always has two peaks at 10 and 25Hz for each of the five fingers. The peaks were considered to be generated in the following two loop systems: The component of the lower frequency originated from the central nervous system as a long loop, and that of the higher frequency originated from the muscle-spine loop system as a short loop. The total power, which was the sum of power spectra ranging from 1.5 to 50Hz, was defined as an evaluation index, and it showed characteristic results for the five fingers. The muscular load produced by two hours of typing work was responsible mainly for the increase of total power and for the change of peak frequencies. The mechanism for the change of the power spectrum due to muscular load was well explained by the two-loop theory. It was found that the fatigue of the fingers due to muscular load could be evaluated by the total power.

Adult↗
PubMed1992

On the visual recognition of moving letter.

The visual recognition (i.e., legibility) of moving object was studied. The numerical letters were mainly used as the objects. The influences of (1) direction of the movement, (2) thickness of line of letter (i.e., stroke width), and (3) design of letter to the visual recognition were measured. From these measurements, the optimal numerical letters were proposed in the first step of the study, which were called as IMAL(initial most optimal arabic letters). The visual recognition of both moving letters IMAL and letters JIS (Japan industrial standard) employed for motionless-state was compared for both the moving and the motionless states. In the presentation for motionless state, letters JIS showed lower error rate, but the statistical significance was not proved, while in the presentation for horizontally moving state letters IMAL showed better visual recognition than letters JIS was the significant level of 5%. Therefore, the useful numerical letters for moving state could be designed in the study. Moreover, the visual recognition of letters IMAL was evaluated for various moving velocities. The optimal moving velocities for both letters IMAL and JIS were found.

Computer-Aided Design↗
PubMed1992

[Studies on Hanganutziu-Deicher antibodies in renal diseases].

H-D antibodies which were known as antibodies detectable in patients with serum sickness have recently been detected in renal diseases. We attempted to detect IgG, IgA and IgM antibodies to N-glycolyl GM3, among other H-D antibodies, by ELISA in various renal diseases and found increased IgM antibody in mesangial proliferative glomerulonephritis, membranoproliferative glomerulonephritis, IgA nephropathy, minimal change nephrotic syndrome and Henoch-Schönlein purpura nephritis (HSPN), elevated IgA antibody in IgA nephropathy and HSPN and raised IgG antibody in IgA nephropathy. In 2 cases of IgA nephropathy, there was noted a good correlation between clinical course and anti-N-glycolyl GM3 antibody titers. Measurement by ELISA of IgG antibody to cytomegalovirus (CMV) seemed as one of immune pathogenetic factors of IgA nephropathy showed a high positive rate for this antibody of IgA nephropathy patients and a positive correlation between the antibody and anti-N-glycolyl GM3 antibody. The key molecule of H-D antigens is N-glycolyl neuraminic acid (NGNA) and this sialic acid does not normally exist in humans. One can surmise, therefore, that in those renal diseases in which there was noted an elevation of anti-N-glycolyl GM3 antibody, this antigen is formed or generated by some unknown mechanism. In other words, it may be that humans are not entirely negative for H-D antigens but have a minimum inherent antigenicity and a potential capacity to synthesize these antigens.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

[Analysis of the determinant factors for open heart surgery without blood transfusion by the quantification theory--possibility of application of maximum surgical blood order schedule for open heart surgery].

In order to complete operations without blood transfusion we have chosen means of preoperative autologous blood saving and intraoperative autotransfusion, but we have not always achieved our purpose. We examined 29 patients (13 patients without blood transfusion and 16 with blood transfusion) to analyze the determinant factors as to whether open heart surgery without blood transfusion may be indicated or not, according to the quantification theory (type II) and to examine the possibility to apply the maximum surgical blood order schedule (MSBOS) for the open heart surgery by the quantification theory (type I). The analysis of determinant factors revealed hematocrit (Ht) value before saving of blood (more than 40%) as the best contributor of possibility of non-blood transfusion surgery, followed by the amount of blood loss during operation (less than 600 ml), the amount of saving blood (more than 800 ml), body weight (less than 70 kg), calculated Ht value on the beginning of cardiopulmonary bypass (CPB) (more than 24%), CPB time (less than 120 minutes) and the amount of postoperative blood loss (less than 600 ml). The prospective using blood volume at the operation was precisely calculated by the values of 4 preoperative factors, that is, the amount of saving blood, calculated Ht value on the beginning of CPB, CPB time and body weight. Therefore it is important to increase the amount of preoperative saving blood and decrease the amount of surgical bleeding in order to perform operations without blood transfusion, and is possible to apply the MSBOS for the open heart surgery.

Adolescent↗
PubMed1992

[Left heart bypass using a centrifugal pump as an adjunct measure for surgery of thoracic descending aorta].

We have employed left heart bypass (LHB) using a centrifugal pump with heparin coated tubes as an adjunct measure for surgery of thoracic descending aortic aneurysm in 8 cases. During aortic cross-clamping, LHB was controlled to maintain the distal pressure above 50 mmHg. In 7 cases, hemodynamics were stable and no complication occurred in relation with this method. However, acute heart failure due to coronary insufficiency occurred in one patient, and subsequent cardiopulmonary bypass was required to maintain systemic circulation. LHB provides adequate distal perfusion and proximal decompression in most cases, and it has also contributed to diminution of intraoperative bleeding. However, LHB can not maintain distal perfusion when acute heart failure occurs, which indicates that we have to select another adjunct measures, such as femorofemoral bypass to avoid distal hypoperfusion in cases with heart diseases.

Aged↗
PubMed1992

[Effects of ethanol intake by the mother rat on learning ability and behavior of offspring rats].

The effects of ethanol intake by the mother rat were studied in five groups of Fischer strain rats; we observed learning ability and behavior of offspring rats using a maze with eight radial arms. I The ethanol free-intake groups (F-) were given a 10% aqueous solution of ethanol, classified by length of ethanol exposure. The mother rats were exposed to ethanol from a young age. The offspring were classified as follows: A. to the delivery (F-DEL), B. to the lactation period (F-NURS), C. to the lactation period, and after weaning, the offspring was continuously exposed to the maze experiment (F-CON). II The ethanol compulsory-intake group (P-DEL) was given a 20% aqueous solution of ethanol, 2 ml/100 g b.w., for the first time on the first day of pregnancy. The solution was given orally once a day through gestation. III The control group was not exposed to ethanol. Radial arm maze observations were made on offspring rats during a total of 30 trials, and we made the following findings: 1) The number of trials required for fulfilling learning criterion was significantly large in F-DEL and F-NURS male rats groups relative to the controls; that is, F-DEL and F-NURS were slow in learning. The number of rats which did not fulfill the learning criterion was significantly large in F-DEL and F-NURS male rats groups, relative to the controls. 2) In all groups running time was shortened with training time, it was result of acclimation to the device and of practice to catch and eating feed. In female rats of the F-DEL and F-NURS groups, running time was not shortened with the training, relative to the control. 3) The behavior of the rats in the F-CON group differed from those in the other groups: The number of well-performed trials was significantly large in F-CON rats group relative to control. They seemed to lack carefulness, and the number of times they failed to eat the feeds even though they succeeded in selecting the correct arm, was significantly large in F-CON female rats group, relative to the controls, in the final 10 trials. Their motion was abrupt and they ran at extraordinarily high speeds. 4) The number of trials required for fulfilling learning criterion was significantly large in the P-DEL rats relative to the controls.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1992

[A case of acute subdural hematoma in the posterior fossa with idiopathic thrombocytopenic purpura].

Intracranial bleeding is one of fatal complications in idiopathic thrombocytopenic purpura although its reported incidence is low. A case of spontaneous acute subdural hematoma complicated with idiopathic thrombocytopenic purpura was reported. He was hospitalized complaining of sudden onset of headache and nasal bleeding without neurological deficit. CT scan revealed subdural hematoma in the posterior fossa especially below the tentorium cerebelli. Further hematological examination proved very low platelet count (1,000/mm3) and antiplatelet antibody in confirmation of a diagnosis of idiopathic thrombocytopenic purpura. As his neurological status was good, he was treated medically. His symptoms and platelet count improved gradually with corticosteroid therapy. Reviewing the literature, acute subdural hematoma with idiopathic thrombocytopenic purpura was quite rare and only three cases reported.

Acute Disease↗