Biomedical subjects

T Komiya

Publications and source records attributed to T Komiya.

At least 109 records · Page 6Linked to original sources

PubMed1994

Isolation and characterization of a novel gene of the DEAD box protein family which is specifically expressed in germ cells of Xenopus laevis.

We have isolated a cDNA of the DEAD protein family from a Xenopus ovary cDNA library. Northern hybridization revealed that the mRNA corresponding to the cDNA [XVLG1 (Xenopus vasa-like gene)] was specifically expressed in adult testis and ovary. The deduced amino acid sequence of XVLG1 was relatively homologous to that of Drosophila vasa. XVLG1 protein was found to be expressed exclusively in adult testis and ovary by immunoblotting with a monoclonal antibody against XVLG1 protein. Immunocytological study showed that XVLG1 protein was expressed in oogonia, oocytes, spermatogonia, spermatocytes, and also in primordial germ cells in stage 46 tadpoles. The monoclonal antibody used in this study specifically stains germ line cells and is useful both as a germ cell lineage marker and in biochemical studies of germ cells.

Amino Acid Sequence↗

PubMed1994

Compliance with antiplatelet therapy in patients with ischemic cerebrovascular disease. Assessment by platelet aggregation testing.

BACKGROUND AND PURPOSE: Antiplatelet therapy is currently one of the methods for preventing transient ischemic attacks and cerebral thrombosis. Because antiplatelet agents are generally administered on a long-term basis, patient compliance is an important factor. The purpose of this study was to determine the compliance of patients during antiplatelet therapy by testing platelet aggregation. METHODS: To establish the conditions for measuring platelet aggregation, the platelet aggregation test was performed in patients taking 81 mg/d aspirin or 200 mg/d ticlopidine at the following final concentrations of aggregation-inducing agents: 0.5, 1, 2, and 4 mumol/L ADP and 0.5 and 2 micrograms/mL collagen. The optimum measurement conditions for assessing patient compliance were determined. Under the conditions determined in the first study, platelet aggregation was assessed, and the effects of treatment were studied in 159 outpatients and 79 inpatients undergoing antiplatelet therapy. If the antiplatelet effect was insufficient, compliance was checked by interview. RESULTS: The agents used and the final concentrations found to be optimum for assessing platelet aggregation were 2 micrograms/mL collagen for patients taking aspirin 81 mg/day and 2 mumol/L ADP for patients taking ticlopidine 200 mg/d. In 17 (10%) of the 159 outpatients, platelet aggregation was not adequately reduced because of noncompliance with their antiplatelet therapy. CONCLUSIONS: This study indicated that monitoring of compliance is important for outpatients on antiplatelet therapy. It is best if platelet aggregation can be checked, but when this is impossible it is necessary to assess compliance periodically and provide patient guidance.

Adenosine Diphosphate↗

PubMed1994

Surgery for tetralogy of Fallot at less than six months of age.

Absence of consensus persists regarding the optimal procedure and timing for the surgical treatment of young infants with symptomatic tetralogy of Fallot. From 1987 through 1992, 56 patients with tetralogy of Fallot were operated on at less than 6 months of age. Forty-one patients (median age 2.9 months) underwent primary repair and 15 (median age 2.4 months) underwent initial palliation. Mean follow-up was 24.2 +/- 16.4 months. No strict protocol was used but patients who received initial palliation were younger, had a smaller pulmonary arterial tree, or had anomalous coronary artery. Two patients died (overall mortality 3.6%; 95% confidence limits 0% to 11%), one after initial palliation (6.7%), and one after primary repair (2.4%) (P = 0.47). Eight of the 15 patients who received initial palliation underwent repair and had an increase in pulmonary anulus size at the time of definitive repair (mean difference Z-value = 2.2 +/- 1.6 standard deviation; p = 0.006). Transannular patch was required in 50% of patients who underwent repair (56% among patients having primary repair versus 13% for patients having initial palliation; P = 0.03). Five patients underwent reoperation. Early primary repair of symptomatic tetralogy of Fallot was achieved with a low mortality rate and is the preferred protocol. Initial palliation remains indicated in case of associated cardiac anomaly, very low weight, or severely hypoplastic pulmonary artery tree.

Age Factors↗

PubMed1994

[A case of endobronchial tuberculosis with high serum CA19-9 and SLX level].

A 43-year-old female was admitted to our hospital with mild cough, sputum and right chest pain. The chest X-ray revealed an inhomogeneous shadow in the right upper lung field and mediastinal lymphadenopathy. At first we considered the patient had bronchogenic carcinoma, as her serum CA19-9 and SLX levels were high and the right upper bronchus was obstructed by necrotic tissues. However bronchoscopic specimen showed necrotizing epithelioid cell granulomas and Mycobacterium tuberculosis was detected, and her disease was diagnosed as endobronchial tuberculosis. The case responded well to anti-tuberculosis chemotherapy. The differential diagnosis between bronchogenic carcinoma and endobronchial tuberculosis was very difficult in this case because of high serum level tumor marker and endoscopic findings, which turned to normal after treatment. We discussed the cause of high serum level of CA19-9 and SLX in nonmalignant lung disease.

Adult↗

PubMed1994

[A case of adenoid cystic carcinoma manifesting Garcin's syndrome--effectiveness of cerebrospinal fluid ferritin as a tumor marker in malignant CNS involvement].

We reported a 69-year-old man exhibiting Garcin's syndrome caused by adenoid cystic carcinoma of the right submandibular gland. The patient first experienced abnormal sensations in his right cheek, and the cranial nerves on his right side gradually became affected. He was admitted for hoarseness and dysphagia. Physical examination revealed a right submandibular mass, and neurological examination revealed that the first cranial nerve and the fifth to twelfth cranial nerves on the right side were affected. Laboratory examination showed a rise of both serum and cerebrospinal fluid (CSF) ferritin, suggesting an intracranial invasion of the submandibular tumor. But other tumor markers, CSF protein and cell counts, CSF pathologic study and radiological studies for the central nervous system (CNS) were all negative. A submandibular tumor biopsy revealed adenoid cystic carcinoma. The radiation therapy, including the skull base, provided relief of the patient's symptoms, the tumor was reduced and serum and CSF ferritin level decreased. It is possible that CSF ferritin is a sensitive marker for CNS involvement of malignant tumor because of its permeability of the blood brain barrier and the absence of correlation between serum and CSF.

Aged↗

PubMed1994

[A 54-year-old man with generalized muscle atrophy and oculomotor paresis].

We report a 54-year-old man with progressive generalized muscle atrophy and ophthalmoparesis in the terminal stage. He was well until 44 years of age (1982) when he noted weakness in his right hand and muscle atrophy; in May of 1985, he noted weakness in his left hand and in both legs. His weakness had become progressively worse, and he became unable to walk in November of 1985. He noted dysarthria one month later, and dysphagia in March of 1986. His difficulty in swallowing had also become worse; he regurgitated foods into the trachea in September of that year, and he developed a low grade fever on the same day. He was admitted to our service on September 24, 1987. On physical examination, general findings were unremarkable, except for low grade fever (37.3 degrees C). On neurologic examination, he was alert and mentally sound. He had normal vision and visual fields; ocular movements were normal. He had moderate weakness in facial muscles, dysarthria, dysphagia, and atrophy in his tongue. He had marked generalized muscle atrophy with fasciculation. He was unable to stand or walk. His muscle strength was not more than 1/6 in any part. The lower extremities were spastic. Deep reflexes were exaggerated in both lower extremities but were normal in upper extremities. Sensation was intact. Laboratory examination was unremarkable, and so was the cranial CT scan. He was treated with nasogastric feeding. He was able to communicate smoothly using his eyes, but a restriction in the vertical gaze was noted in February of 1989. The range of ocular movement was better in the oculocephalic reflex compared with his spontaneous vertical eye movements. In April of 1990, his horizontal gaze also had become slow, and he was complicated by bronchial asthma. He was treated with 20 mg/day of prednisolone; after the institution of prednisolone, his horizontal eye movement showed much improvement. In the terminal stage, he was able to move his eyes only very slowly; vertical gaze was impossible. His subsequent course was complicated by respiratory tract infection and septicemia, and he expired on July 15, 1992. The patient was discussed in a neurological CPC, and the chief discussant arrived at the conclusion that this patient had amyotrophic lateral sclerosis with oculomotor paresis. Post-mortem examination revealed spongy change involving the posterior column and the posterior spinocerebellar tract, in addition to severe degenerative change in the upper and the lower motoneurons, which were consistent with amyotrophic lateral sclerosis.(ABSTRACT TRUNCATED AT 400 WORDS)

Amyotrophic Lateral Sclerosis↗

PubMed1994

[Modified Fontan procedure for complex cardiac anomaly with nonconfluent pulmonary artery].

Modified Fontan procedure was successfully performed in two patients with complex cardiac anomaly and nonconfluent pulmonary artery. A nonconfluent portion of the pulmonary artery was interposed with a xenopericardial roll. In one patient, the central pulmonary artery was completely absent. Two-staged reconstruction of the central pulmonary artery was carried out through a left thoracotomy and a median sternotomy before the Fontan procedure. In the other patient, a juxtaductal segment of the pulmonary artery was nonconfluent. Correction of the nonconfluent pulmonary artery was performed concomitantly with the Fontan procedure. Fenestrated Fontan procedure seemed to be the beneficial modification for survival. Both patients have been day well during the midterm follow-up period.

Cardiac Surgical Procedures↗

PubMed1994

[A case report of modified Bentall procedure, aortic arch replacement and mitral valve replacement for a patient with Marfan's syndrome].

A 20-year-old man of Marfan's syndrome who had mitral valve regurgitation, annuloaortic ectasia with aortic valve regurgitation and aortic arch aneurysm was successfully treated with radical operation. Mitral valve replacement was performed with superior wall incision of the left atrium directly. Complete transection of the aortic root made it easy to reach the mitral valve. The diameter of his ascending aorta was 70 mm, and modified Bentall' procedure, Carrel patch method, was performed. Aortic arch was 40 mm in diameter, and total aortic arch replacement was performed under hypothermic circulatory arrest. After the combined operation, patient was recovered uneventfully.

Adult↗

PubMed1994

[Pretectal syndrome caused by a plaque of multiple sclerosis].

We report a 20-year-old woman who presented with pretectal syndrome. She was well until September 12, 1991 when she noted an onset of difficulty in focusing her eyes. On neurologic examination, she showed convergence-retraction nystagmus and restriction of vertical eye movements more in the upward direction. A cranial CT scan revealed no abnormality. An oligoclonal band was detected in CSF. An MRI using Hitachi MRH-500 (0.5 T) revealed an abnormal high signal intensity lesion at the ventral area of the midbrain aqueduct, and another small lesion in the temporal white matter on the left. In addition, periventricular scattered small lesions were also visualized. Hydrocephalus, tumors and cerebrovascular disorders are common causes of pretectal syndrome, but multiple sclerosis is a rare one. Problems associated with the similar terminologies including Parinaud's syndrome, sylvian aqueduct syndrome or dorsal midbrain syndrome were discussed. According to Ranalli (1988), fibers mediating the upward gaze originate in the rostral interstitial MLF (riMLF), cross through the posterior commissure, and terminate in the contralateral oculomotor complex. On the other hand, downward gaze fibers take another route to the oculomotor complex. This may be a reason for the dissociation of the upward and downward gaze palsy, and the riMLF seems to be one of the most important structures responsible for the upward gaze.

Adult↗

PubMed1993

MyoD and myogenin act on the chicken myosin light-chain 1 gene as distinct transcriptional factors.

Expression of MyoD, myogenin, MRF4, and Myf-5 converts nonmuscle cells to muscle cells. In an attempt to analyze the roles of these factors, we have investigated their effects on transcription driven by the promoter of the chicken myosin alkaline light-chain (MLC1) gene. The activation by CMD1 or c-myogenin (chicken MyoD or myogenin, respectively) was dependent on the existence of a muscle-specific regulatory region located from positions -2096 to -1743. Its distal half, containing a pair of E boxes (CANNTG), had been previously characterized as an enhancer responsive to CMD1 but not to c-myogenin. In this study, we report the identification of another enhancer in the muscle-specific regulatory region which is preferentially responsive to c-myogenin. Deletion and mutation analyses indicated that this enhancer requires a single E box and its flanking sequences. Furthermore, analysis of chimeric proteins of CMD1 and c-myogenin indicated that regions outside the basic helix-loop-helix domain of c-myogenin are involved in the specificity of the enhancer. These results show that CMD1 and c-myogenin act on the MLC1 gene by recognizing different upstream DNA sequences and that direct or indirect interactions between the regions outside the basic helix-loop-helix domain and flanking sequences of E boxes are involved in the target sequence specificity.

Animals↗

PubMed1993

[Granule-accumulation in VERO cells used for determination of antitoxin titration by micro cell culture method: I. Influence of mouse serum].

When the titration of diphtheria antitoxin of mouse serum was carried out by micro cell culture method using VERO cells, a large number of granules were observed in the cells. In order to examine the influence of this phenomenon on the titration of antitoxin, kinetics of the granule-accumulation was investigated. The granule-accumulation occurred in the cells in the culture medium to which either immunized or normal mouse serum was added. The granule-rich cells appeared at the dilution of the serum less than 1:32 and increased in number with the concentration of the serum. After 4 days of incubation 88% of the cells showed granule-accumulation when undiluted serum was added. Besides the mouse serum, those from guinea-pigs, horses, fetal calves and humans were examined. However, intensive accumulation of granules such as shown with mouse serum was not observed. From these results it was suggested that mouse serum might have some unknown mechanism which caused the remarkable accumulation of granules in VERO cells. The nature of granule and influence of this phenomenon on the titration of diphtheria antitoxin will be presented in an accompanying paper.

Animals↗

PubMed1993

[Granule-accumulation in VERO cells used for determination of antitoxin titration by micro cell culture method: II. Nature of granules and influence on the potency testing of diphtheria toxoid].

Accumulation of granules occurs in VERO cells when mouse serum was added in high concentration. The nature of the granule and influence of the granule-accumulation on the potency testing of diphtheria antitoxin were studied. The concentration of triglyceride in VERO cells increased 15 folds after 24 hours of incubation by the addition of undiluted mouse serum. Kinetical study of the increase of triglyceride and electron microscope observation suggested that the accumulated granules might be oil droplets with an average diameter of 0.27 micron. The end point reaction of neutralization of diphtheria toxin by the standard antitoxin was analyzed by the addition of mouse serum to the micro cell culture using VERO cells. The mean values of the end point reactions in the cell cultures added with high concentrations of mouse serum were -2.324, -2.338 and -2.346, while that of the control group was -2.343. The variance of these mean values in the experiment and control groups were 0.0017, 0.0024, 0.0017 and 0.0021, respectively. A test of homogeneity of variance for these data showed no significant difference between them. Furthermore, antitoxin titer of the serum specimens of mouse immunized with diphtheria toxoids determined by the micro cell culture method were compared with that obtained by rabbit skin test; a high correlation between the antitoxin titers by the two techniques was recognized. The results were comparable with those of guinea-pig sera. From these results it is evident that little influence, if any, was observed in the potency testing of diphtheria antitoxin using VERO cells, in spite of the remarkable accumulation of granules.

Animals↗

PubMed1992

Differential trans-activation of muscle-specific regulatory elements including the mysosin light chain box by chicken MyoD, myogenin, and MRF4.

We have isolated cDNAs encoding a chicken homologue of MRF4 (cMRF4) in addition to chicken MyoD (CMD1) and myogenin (c-myogenin) described previously. In an attempt to understand the roles that cMRF4, CMD1, and c-myogenin play in chicken myogenesis, the effects of these factors on muscle-specific cis-elements identified in regulatory regions of myosin alkali light chain (MLC) genes were examined. The promoter analysis of some of MLC genes has revealed two sorts of muscle-specific positive regulatory elements to date, an enhancer located upstream of the adult type LC1 gene and a cis-element, termed an MLC box, conserved among promoters of various MLC genes. The LC1 enhancer was exclusively trans-activated by CMD1. Although c-myogenin also activated transcription driven by the LC1 promoter, it was suggested that c-myogenin requires a cis-element(s) other than the CMD1-responsive enhancer. Chicken MRF4 could not trans-activate any of the constructs containing the LC1 promoter. In contrast, the promoter of the embryonic L23 gene was trans-activated by all of the three factors. From deletion and mutation analysis, the MLC box was shown to be involved in their positive regulation. These results extend previous observations that individual myogenic regulatory factors exhibit different capabilities in transcriptional activation of muscle-specific genes by acting distinctively upon their regulatory elements.

Amino Acid Sequence↗

PubMed1992

A novel class of enkephalinase inhibitors containing a C-terminal sulfo group.

A new series of sulfonic acids were synthesized and tested for their enkephalinase inhibitory activity. Among them, the most potent was N-(2-benzyl-3-mercaptopropionyl)metanilic acid 10i with an IC50 value of 0.27 nM. Several other analogues (10a,b,j,n,o,gg,hh) showed the inhibitory activity comparable to or greater than thiorphan (IC50 = 2.6 nM), a C-terminal carboxyl-containing inhibitor of enkephalinase. Thus compounds containing a C-terminal sulfo group, instead of the C-terminal carboxyl group, were found to show a remarkably high level of inhibition of enkephalinase. The analgesic activity of 10b, (S)-10b, and (R)-10b was also evaluated by the phenylbenzoquinone writhing test.

Analgesics↗

PubMed1992

Positive and negative gene regulation in muscle.

By the analysis of cis and trans-acting element involved in transcriptional regulation of chicken myosin alkali light chain genes, we have identified the MLC box, muscle specific enhancer element and negative regulatory element. The MLC box is an essential element for the expression of MLC genes located at approximately 100 bp upstream from mRNA start sites. The core sequence of MLC box is similar to the consensus of actin gene CArG box and SRE of c-fos oncogene. In vitro DNA-protein binding assay has revealed that the MLC box, CArG box and SRE might bind to a common or a similar protein complex. CMD1, cMyogenin, and cMRF4 transactivate the promorter with an intact MLC box, but not the promoter lacking MLC box, indicating that the MLC box itself is transactivated by the myogenic regulatory factors. This transactivation must have been due to the indirect effect of the myogenic regulatory factors, because chicken myogenic factors do not bind to the MLC box. A cis element identified at about 150 bp upstream from the cap site of cardiac MLC gene suppresses the cardiac MLC gene expression in skeletal muscle cells but not in cardiac muscle cells. The protein(s) bound to NRE might be identical with one of proteins bound to SRE. NRE may block the function of MLC box and resultantly inhibits the expression of cardiac MLC1 gene in skeletal muscle cells. Skeletal muscle enhancer at -2 kb of skeletal MLC1f gene is composed of two subelements P and D, cooperative action between them is required for sufficient enhancer activity. CMD1 and myogenin bind to the enhancer sequences of skeletal MLC1 gene and MCK gene and transactivate these genes preferentially in skeletal muscle cells. In addition to the CMD1 responsible enhancer, another cis-element is required for transactivation of the MLC1f gene by cMyogenin. An E-box adjacent to MLC box may co-work with the enhancer to increase the expression of MLC1f gene. Muscle specific and developmentally regulated expression of MLC gene family is regulated by the combination of these cis and trans-acting elements.

Animals↗

PubMed1992

[A case report of left ventricular myxoma].

We reported a case of successful surgical extirpation of a left ventricular myxoma arising from the anterior wall of the left ventricle. A 17-year-old asymptomatic boy had been followed due to premature ventricular contractions. Two-dimensional echocardiography revealed a small mass in the left ventricle. He underwent transaortic extirpation of the mass under extracorporeal circulation in November, 1989. The gelatinous mass of 11 by 9 by 5 mm and weighing 0.4 g was a myxoma pathohistologically. His postoperative course has been uneventful. Left ventricular myxomas are very rare. In the literature, 26 cases in English and 6 in Japanese have been reported. Recurrence was reported in one case, thus careful follow-up is necessary.

Adolescent↗

PubMed1991

Identification of mutations that occurred on the genome of Japanese encephalitis virus during the attenuation process.

The total nucleotide sequences of the genomes of two Japanese encephalitis virus (JEV) strains, the attenuated vaccine strain SA14-14-2 and its parental virulent strain SA14, were determined by using the molecular cloning technique. The sequence analysis revealed that both virion RNA molecules were 10,976 nucleotides long with 95 and 585 flanking bases at the 5' and 3' untranslated sequences, respectively. A single, long open reading frame spanning 10,296 nucleotides was observed to encode a polyprotein of 3432 amino acid residues. When these sequences were compared with each other, 57 nucleotide substitutions were found to be scattered all over the genome. Of these, 24 resulted in amino acid changes within viral proteins. Structural proteins C and E contain one and eight amino acid changes, respectively. Of the nonstructural proteins, NS1 contains three, NS2a two, NS2b two, NS3 four, NS4a one, NS4b one, and NS5 two amino acid substitutions. The 5'- and 3'-terminal untranslated regions contain one- and two- point mutations, respectively. These data and comparative studies with other JEV strain genomes provide a molecular basis for investigating attenuation mechanisms of JEV.

Amino Acid Sequence↗

PubMed1991

[Amnestic syndrome with bilateral lesions restricted to the field CA-1 of both hippocampi--a case report with CT and MRI findings].

We report a 69-year-old woman with an amnestic syndrome who showed small infarcts in bilateral hippocampi by MRI. She had a sudden onset of recent memory impairment and was admitted to our hospital. On admission, she showed marked impairment in recent memory tests. Other neurological findings including the mental status were essentially normal. Four weeks after the onset, the memory test using simple figures was normalized, however, that using a simple sentence by the auditory route was still abnormal. Cranial CT scans and MRI revealed small lesions consistent with infarcts in the CA-1 field of both hippocampi. Her memory disturbance lasted longer than that of TGA. To our knowledge, this is the first report of the amnestic syndrome with proved discrete lesions in the CA-1 field of the hippocampi in human. Our case suggests the importance of the CA-1 field for recent memory.

Aged↗