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Biomedical subjects

T Kojima

Publications and source records attributed to T Kojima.

At least 235 records · Page 13Linked to original sources
PubMed1999

Radiofrequency catheter ablation of coexistent atrioventricular reciprocating tachycardia and left ventricular tachycardia originating in the left anterior fascicle.

Coexistence of supraventricular tachycardia and ventricular tachycardia is rare. A patient with no structural heart disease and wide QRS complex tachycardia with a right bundle block configuration and right-axis deviation underwent electrophysiological examination. A concealed left atrioventricular pathway (AP) was found, and atrioventricular reciprocating tachycardia (AVRT) and left ventricular tachycardia (VT) originating in or close to the anterior fascicle of the left ventricle were both induced. Radiofrequency (RF) catheter ablation of the concealed left AP was successfully performed. Ten months later, VT recurred and was successfully ablated using a local Purkinje potential as a guide. Coexistent AVRT and idiopathic VT originating from within or near the left anterior fascicle were successfully ablated.

Adult↗
PubMed1999

[Adhesive and sealing effects of TO-193 on tissues and organs in various experimental models].

We studied the adhesive and sealing effects of sheet style fibrin adhesive, TO-193 (TachoComb), on some tissues and organs, comparing them with those of sheet style collagen agent, collagen sponge, Novacol, and Avitene and liquid fibrin adhesive agent, Beriplast P. TO-193 showed more a potent adhesive effect on liver than the sheet style collagen agents and was more potent on bone and skin than the liquid fibrin adhesive agent. Furthermore, TO-193 had a potent sealing effect at the site of incomplete suture immediately after application on a motile organ such as lung and stomach. These effects may be partly attributable to rapid expression of the effect due to the presence of a high concentration of fibrinogen on coverage. Enhancement of fibrin penetrability to the tissues by compression and inhibition of cleavage of coverage by the collagen sponge also may be participating in the effects of TO-193. These results suggest that TO-193 will be a valuable adhesive and sealing agent.

Animals↗
PubMed1999

Development of a new high-speed measuring system to analyze the dental cast form.

A new non-contact measurement system employing of a line laser and CCD camera was developed to rapidly measure maloccluded dental casts with large depth and high accuracy. In this system, the measuring interval along the line laser and the model scanning direction perpendicular to the line laser were both 0.2 mm. By averaging the raw data through repetitious input and smoothing by local filtering, the noise was effectively decreased. Sub-pixel processing, which calculates the pixel position with the largest brightness within one pixel, improved the accuracy in the measurement to 22 microns compared with 65 microns before sub-pixel processing. Dental casts with malocclusion were measured with this system. The time and the depth for the measurement were about 10 minutes and 60 mm, respectively. This was a vast improvement compared with our previous system employing a point laser. In the CG of the measured dental casts, smooth and detailed surface morphology were sufficiently reproduced, and recognition of the characteristic points in the cast could be accomplished with the accuracy of 30 microns. This measurement system will be helpful to analyze the dental cast form with malocclusion in progress.

Humans↗
PubMed1999

[Importance of drug selection and the use of sensitivity tests for the eradication therapy for Helicobacter pylori].

Drug selection for eradication therapy of H. pylori, considering their drug resistance was evaluated. The measurement of resistant colonies was performed in blood agar plates using the MIC method and the criteria for resistance was as follows: MIC > 1 mg/l with AMPC, MIC > 2 mg/l with CAM and MIC > 8 mg/l with MNZ. Primary resistant colonies were found in 0% with AMPC, 8.9% with CAM and 5.9% with MNZ. Secondary resistant colonies were found in 0% with AMPC, 50.0% with CAM and 54.5% with MNZ. CAM and MNZ showed high resistance rate and among them, colonies resistant to CAM were also highly resistant to MNZ. But colonies resistant to MNZ (acquired after CAM) were all sensitive to AMPC. Considering this issue and the absence of resistance to AMPC, we considered the triple therapy with AMPC, MNZ and a PPI as the best option for the eradication of H. pylori.

Amoxicillin↗
PubMed1999

[A case of synchronous multifocal urothelial tumors in a patient with phenacetin abuse].

A 79-year-old male with phenacetin abuse was admitted to our University Hospital for treatment of asymptomatic gross hematuria. Intravenous urograpdy and computed tomography revealed synchronous right renal pelvic carcinoma and bladder carcinoma. Right nephroureterectomy and transurethral resection of bladder tumor (TUR-Bt) were performed. Histologically, right renal pelvic tumor and bladder tumor were both transitional cell carcinomas of grade 2, pT1, and grade 1 = 2, Ta, respectively. Additionally, pathological examination revealed two distal ureteral tumors, which were transitional cell carcinomas of grade 2, pTa. He also had a history of heavy tobacco-smoking (20 cigarettes per day for 50 years). We discuss the relationship between transitional cell carcinoma and phenacetin abuse as well as the influence of tobacco-smoking, and review the literature.

Aged↗
PubMed1999

[Differential diagnosis of schizophrenic symptoms complicated with brain anomalies including bilateral temporal arachnoid cysts by eye mark recorder and PET: a case study].

Bilateral temporal arachnoid cysts and other intracranial congenital lesions including a moderately large left temporal arachnoid cyst accompanied by remarkable dysplasia of the temporal lobe in particular were discovered by chance during computerized axial tomography of a 26-year-old Japanese male who had been diagnosed as schizophrenia approximately 10 years earlier. A detailed re-assessment revealed no other organic symptoms or signs. His symptoms and clinical course met the DSM-IV criteria for schizophrenia, disorganized type. Based on his symptoms, positron emission tomography (PET) and the eye-movement recording test developed by Kojima et al. were performed. In addition, psychological tests including WAIS, Rorschach Test, and Wechsler's Memory Test were administered for further differential diagnosis. PET using continuous inhalation of oxygen 15-gas revealed a regional decrease in CBF and CMRO2 in the superior medial frontal lobe including the anterior cingulate gylus, findings sometimes associated with schizophrenia. However, no abnormal findings were noted around the arachnoid cysts. In the eye-movement recording test, several parameters including the responsive search score (RSS) were about the same level as that commonly observed in schizophrenics and are classified as schizophrenia by discrimination analysis. The psychological tests offered no reason to doubt the diagnosis of schizophrenia. Thus, the patient was diagnosed as schizophrenia with arachnoid cysts and other intracranial lesions. The way of diagnosis we used here might bring forth a breakthrough in schizophrenia research by differentiating schizophrenia from the other organic brain diseases.

Adult↗
PubMed1999

[Paragonimiasis Miyazakii with variable X-ray shadows].

A 77-year-old woman was admitted to our hospital with hemoptysis and weight loss. She had eaten 15 raw freshwater crabs about 5 months before the onset of her clinical symptoms. Chest X-ray films obtained on the first admission showed left pleural effusion. After 1 week of chemotherapy with SBTPC, the pleural effusion disappeared. Two months later, the patient was re-admitted with recurrent hemoptysis. Chest X-ray films showed a solitary nodular lesion in the right lung. Eosinophilia and increased serum IgE levels were detected. The solitary nodular lesion moved from the middle to upper field of the right lung during the patient's 3-week stay in the hospital. Serologic tests yielded a conclusive diagnosis of Paragonimiasis miyazakii infection. Praziquantel administration relieved the patient's symptoms.

Aged↗
PubMed1999

Regulation of murine protein C gene expression in vivo: effects of tumor necrosis factor-alpha, interleukin-1, and transforming growth factor-beta.

Protein C is a precursor of the anticoagulant serine protease, activated protein C, which inhibits coagulation factors Va and VIIIa. Although the liver appears to be the primary site of protein C synthesis, we previously demonstrated that the kidney and male reproductive organs also expressed abundant protein C mRNA in the mouse. In the present study, we further investigated the effects of tumor necrosis factor-alpha (TNF-alpha), interleukin-1 (IL-1), and transforming growth factor-beta (TGF-beta) on the expression of protein C mRNA in the principal producing organs, i.e., the liver, kidney, and testis. Both quantitative reverse transcription-PCR assay and in situ hybridization analysis revealed that TNF-alpha decreased protein C mRNA expression in the liver, kidney, and testis. IL-1 also down-regulated protein C mRNA expression in the liver and testis, but not in the kidney. In contrast, TGF-beta unchanged the expression level of protein C mRNA in these three organs. These observations suggest that TNF-alpha and IL-1 may contribute to an increase in the procoagulant potential by downregulation of protein C synthesis in the tissues during inflammatory processes.

Animals↗
PubMed1999

[Relation between temporomandibular joint disorder and subjective symptoms of fatigue].

An investigation was performed for the purpose of guaging the relation between temporomandibular joint disorder on the one hand and occupational category and subjective symptoms of fatigue on the other. Subjects were 2,414 workers (1,598 male, 816 female) in small and medium size enterprises at 67 workplaces in Hiroshima Prefecture. A comparison of cases with and without temporomandibular joint disorder showed that there were more complaints of fatigue among those with the disorder. Given these indications that temporomandibular joint disorder was related to occupation, it is possible that temporomandibular joint disease may be a work-related disease.

Adult↗
PubMed1999

Sex-related differences in plasminogen activator and plasminogen activator inhibiting activities in young and aged rats.

The purpose of this study was to determine whether aging influences the sex-related differences in fibrinolytic activity in rats. We measured plasminogen activator (PA) activity and plasminogen activator inhibiting (PAI) activity in 5-, 12-, 45-, and 60-week-old male and female rats. We also examined the effects of gonadectomy and sex hormone-treatments in adult male and female rats. The increase in age did not influence the PA activity in the male or female rats. However, the PA activity was higher in the female rats than in the males in all four age groups. Orchidectomy caused a significant increase in PA activity in the male rats. Estradiol treatment induced a significant increase of PA activity in ovariectomized female rats. Testosterone treatment resulted in a decrease of PA activity in orchiectomized male rats. The increase in age had an effect on PAI activity; the activity level in the 45- and 60-week-olds was stronger than that in the 12-week-old rats. The PAI activity was not significantly different between the normal rats of each sex. Gonadectomy did not influence the PAI activity in male or female rats, and testosterone and estradiol treatments also did not affect PAI activity in gonadectomized male and female rats. We found that the increase in age induced a decrease in the fibrinolytic system in the rats, and that there were sex-related differences in the fibrinolytic system in even 60-week-old rats.

Aging↗
PubMed1999

Anxiolytic 5-hydroxytryptamine1A agonists suppress firing activity of dorsal hippocampus CA1 pyramidal neurons through a postsynaptic mechanism: single-unit study in unanesthetized, unrestrained rats.

Recent behavioral studies indicate that conditioned fear response to contextual stimuli is reduced effectively by anxiolytic 5-hydroxytryptame (5-HT)1A agonists. Since the hippocampus seems to play an essential role in associative fear memories evoked by context, it is important to assess the effect of 5-HT1A agonists on pyramidal cell activity in the hippocampus. We examined the effects of 5-HT1A agonists on the spontaneous firing rate of hippocampal CA1 pyramidal neurons in unanesthetized, unrestrained rats. Systemic administration of selective 5-HT1A agonists, 8-hydroxy-2-(di-n-propylamino)tetralin, buspirone, ipsapirone, and flesinoxan produced a dose-dependent inhibition of neuronal activity. Putative 5-HT1A antagonists NAN-190 1-(2-methoxyphenyl)-4-[4-(2-phthalimido)butyl]piperazine and (-)-pindolol did not change neuronal activity of CA1 pyramidal neurons. The suppression of neuronal activity by buspirone was antagonized by NAN-190 but not by (-)-pindolol. Lack of antagonistic activity of (-)-pindolol for the suppression of pyramidal neurons via a postsynaptic mechanism is consistent with the results of recent electrophysiological experiments in anesthetized rats. Pretreatment with parachlorphenylalanine did not change the spontaneous firing rates of hippocampal CA1 pyramidal neurons or abolish the suppressant effects of buspirone on these neurons. Taken together, the present results strongly suggest that suppression of the hippocampal CA1 pyramidal neuronal activity by anxiolytic 5-HT1A agonists in awake rats is mediated by postsynaptic 5-HT1A receptors located on pyramidal neurons.

Animals↗
PubMed1998

Determination of acrolein in human urine by headspace gas chromatography and mass spectrometry.

A rapid and sensitive headspace gas chromatographic and mass spectrometric (GC-MS) method was developed for the determination of acrolein in human urine. A 0.5-ml urine sample in a glass vial containing propionaldehyde as an internal standard was heated at 80 degrees C for 5 min. A 0.1-ml volume of headspace vapor was injected into a GC-MS instrument. Acrolein and propionaldehyde were coeluted at 3.1 min using a DB-1 capillary column, and well separated by selective ion monitoring (SIM) mode using ions m/z 56.05 and m/z 58.05. The interassay and intraassay coefficient of variation were 0.99% and 3.3%. The calibration curve demonstrated a good linearity throughout concentrations ranging from 1 to 1000 nM. However, due to a wide variation of acrolein evaporation rates from human urine, a calibration curve must be established for each urine specimen using a standard addition method and detection limit varied from 1 to 5 nM. The total analysis time for two samples from one urine specimen required about 15 min. Therefore, this method is convenient for the urgent monitoring of urinary acrolein in patients to whom alkylating agents are administered.

Acrolein↗
PubMed1998

Identification of the five hydrophilic residues (Lys-217, Lys-218, Arg-359, His-360, and Arg-513) essential for the structure and activity of vitamin K-dependent carboxylase.

Vitamin K-dependent carboxylase catalyzes the posttranslational conversion of glutamic acid to gamma-carboxyglutamic acid in vitamin K-dependent proteins. The clustered charged-to-alanine scanning mutagenesis of bovine carboxylase has identified five distinct candidate regions (I. Sugiura et al., J. Biol. Chem. 271, 17837-17844, 1996) with significant loss-of-function phenotype. To further specify the residues essential for the structure and function of the enzyme, Lys-217, Lys-218, Arg-359, His-360, Lys-361, Arg-513, and Lys-515 were analyzed by substituting to alanine individually. All the mutants except for K217A were expressed in Chinese hamster ovary cells. The carboxylase activities of R359A, H360A, and R513A decreased in parallel with the vitamin K epoxidase activities. Both carboxylations by R359A and H360A were stimulated saturatively at 1 microM factor IX propeptide (proFIX18) concentration, but that by R513A was not at a concentration up to 128 microM. K218A completely lost the enzyme activities but it cross-linked to the propeptide, suggesting that Lys-218 is critical for enzyme activity without affecting propeptide binding. We conclude that Lys-218, Arg-359, and His-360 are involved in the catalytic event, and Arg-513 participates in propeptide binding.

Alanine↗