Search PubMed⌕ Search

Biomedical subjects

T Ohara

Publications and source records attributed to T Ohara.

At least 91 records · Page 5Linked to original sources

[Comparison of therapeutic effects of SMANCS (+TAE) and Non-SMANCS/LpTAE].

Therapeutic effects of SMANCS and LpTAE were evaluated for hepatocellular carcinoma (HCC). Since June 1995, SMANCS has been used in 59 patients for their first treatment. LpTAE had been performed for HCC before introduction of SMANCS in our hospital, and 71 patients treated after 1992 were chosen for comparison with the therapeutic effect of SMANCS. Among the patients treated with SMANCS, complete and partial responses (CR and PR) were obtained in 24 cases (41%) and 17 cases (33%), respectively. SMANCS accompanied by TAE was more effective than SMANCS alone. The effects did not depend on the level of the hepatic arterial branch at which SMANCS was administered. In patients treated with LpTAE, CR and PR were obtained in 12 cases (17%) and 18 cases (25%), respectively. SMANCS was significantly more effective than LpTAE. Because of our short experience with SMANCS, we could only show a two year survival rate. The one- and two-year survival rates for SMANCS were 71% and 57%, respectively. They were not significantly different from those for LpTAE, at 80% and 60%. Despite good results of treatment for HCC, a better prognosis could not be expected by SMANCS in this study. These results may be explained as follows. The evaluating the cause of death within two years after first treatment, hepatic failure was more common in patients treated with SMANCS. After treatment by SMANCS, 11 patients (55%) died from hepatic failure. On the other hand, 4 patients (15%) died from hepatic failure after LpTAE. Although there is no significant difference of Child Pugh score, this may indicate that SMANCS has been used for patients with lesser hepatic reserve and this leads to early deaths in patients treated with SMANCS. However, because of the short experience in this study, further observation is necessary for precise evaluation of clinical efficacy of SMANCS.

Antineoplastic Agents↗

[MRI findings in a testicular epidermoid cyst: a case report].

A 21-year-old man was admitted with a painless mass in the left testis. Physical examination revealed a firm, small-finger sized, mass lesion with a smooth surface in the left testis. The ultrasonographic appearance was a hypoechoic lesion with an echogenic rim in the left testis. Magnetic resonance imaging (MRI) findings showed the echogenic rim to be a low-signal zone on both T1 and T2-weighted images. The center, on T2-weighted images, had a low signal intensity, with peripheral high signal intensity. Under a preoperative diagnosis of epidermoid cyst, the mass was resected surgically with preservation of the testis. Histopathological diagnosis confirmed an epidermoid cyst. Preoperative ultrasonographic and MRI findings suggested a benign lesion, thus permitting preservation of the testis.

Adult↗

Accumulation of pyrraline-modified albumin in phagocytes due to reduced degradation by lysosomal enzymes.

Previous studies suggested that the interaction between proteins modified by advanced glycation end products (AGEs) and cells, such as macrophages, may be involved in diabetic angiopathy. Pyrraline is one of the AGEs and known to be elevated in plasma of diabetic rats and humans, and is present in vascular lesions of diabetic and elderly subjects. We examined whether modification of albumin by pyrraline influences its degradation by macrophage-like cell line, P388D1 cells. Degradation of pyrraline-modified albumin by these cells was diminished, causing accumulation of the albumin in these cells. The susceptibility of pyrraline-modified albumin to lysosomal proteolytic enzymes was reduced by approximately 40% in vitro, while lysosomal activity in the cells per se was not affected. This phenomenon was also observed when human monocytes were used instead of P388D1 cells. Our results suggest that accumulation of pyrraline-modified albumin in P388D1 cells is due to the reduced susceptibility of the protein to lysosomal enzymatic degradation. Such alterations in the interaction between AGEs-modified protein and phagocytes may contribute to angiopathy in elderly subjects and patients with diabetes.

Albumins↗

SDZ ENA 713 facilitates central cholinergic function and ameliorates spatial memory impairment in rats.

We have clarified the effects of SDZ ENA 713 (ENA), a new phenyl-carbamate derivative, on the spatial learning impairment and neurochemical indices of central cholinergic neurons in rats. Basal forebrain (BF) lesioning with ibotenic acid markedly impaired acquisition ability in the water maze task without changing swimming rates and decreased choline acetyltransferase (ChAT) activity in the frontal cortex of rats. ENA (0.1, 0.2 mg/kg, p.o.) significantly ameliorated the impairment in acquisition ability in a dose-dependent manner. At 0.2 mg/kg, ENA prevented the reduction in ChAT activity. In normal rats, ENA (1 mg/kg, p.o.) increased extracellular ACh concentration of the prefrontal cortex. On the other hand, tissue concentrations of norepinephrine, serotonin, dopamine and their metabolites were not changed in the frontal cortex, hippocampus and striatum of normal rats. These results suggest that ENA ameliorates spatial learning disability by not only facilitating the cholinergic transmission, but normalizing impaired ChAT activity in the learning-impaired rat model.

Animals↗

Ameliorating effects of SDZ ENA 713 on age-associated decreases in learning performance and brain choline acetyltransferase activity in rats.

In the present study, we have investigated the effects of SDZ ENA 713 on spatial learning deficits in aged rats. Using the same animals, the effect of SDZ ENA 713 on choline acetyltransferase was simultaneously studied to obtain a basis for the behavioral study. In the aged rats, the spatial learning and choline acetyltransferase activity in the frontal cortex were significantly deteriorated compared with young adult rats. SDZ ENA 713 (0.2 mg/kg) significantly shortened the time to reach a hidden platform without affecting swim rates in the water maze task. SDZ ENA 713 (0.1 and 0.2 mg/kg) inhibited aging-induced decreases in choline acetyltransferase activity in the frontal cortex. These results suggest that SDZ ENA 713 ameliorates aging-induced learning deficits and cholinergic dysfunction in rats.

Aging↗

Kidney transplantation and liaison psychiatry, part I: anxiety before, and the prevalence rate of psychiatric disorders before and after, transplantation.

We examined psychiatric problems before and after kidney transplantation in a sample of 36 patients with end-stage renal failure. The prevalence rate of psychiatric disorders was 11.1% (4 of 36 cases) before the transplantation and 36.1% (13 of 36 cases) within 2 months after the transplantation. Except for a patient with schizophrenic disorder, no patients were found to have a psychiatric disorder from 2 to 6 months after the transplantation. In this study, we also examined anxieties and/or conflicts related to the transplantation using the synthetic house-tree-person (HTP) drawing test, a measure of mood states by means of a non-verbal expression method. The upper part of the tree trunk was not drawn in 25% of this sample (5 of 20 cases). In the HTP drawing tests immediately after the transplantation, however, trees missing the upper part of trunk were not drawn. Based on these findings, we discussed psychiatric problems in kidney transplantation.

Adolescent↗

Kidney transplantation and liaison psychiatry, part II: A case of dissociative identity disorder.

The authors examined the case of an adolescent patient with dissociative identity disorder secondary to psychological shock of a transplant rejection response. Psychiatric symptoms consisted of three components: visual hallucinations and delusions as a psychological defense against the anxiety of a transplant rejection; appearance of three personalities including proper self, the dead child (donor), and a prophet with strong predicting power; and a twilight state. These psychiatric symptoms may have been related to two psychological factors: immature personality characteristics formed during hemodialysis, and post-traumatic stress caused by a chronic rejection reaction from the patient's first transplant.

Adolescent↗

Accessory scrotum with penoscrotal transposition and retrocerebellar arachnoid cyst: a case report.

A 2-year-old boy presented with an accessory scrotum associated with penoscrotal transposition and a perineal lipoma. He also had a retrocerebellar arachnoid cyst. The accessory scrotum was resected with concurrent scrotoplasty. The retrocerebellar arachnoid cyst was seen on a subsequent brain computed tomography scan and was left untreated because there was no evidence that the volume was increasing.

Arachnoid Cysts↗

Inhibitory effects of tenilsetam on the Maillard reaction.

It has been hypothesized that advanced Maillard reaction in vivo could explain some of the age- and diabetes-related changes. Furthermore, involvement of the Maillard reaction with Alzheimer's disease has also been suggested, as advanced glycation end products, such as pyrraline and pentosidine, were demonstrated to localize in lesions of the disease. Although aminoguanidine has been studied extensively and established as an inhibitor of the Maillard reaction, other candidates have not been investigated thoroughly. In the present study, we examined the inhibitory effect of tenilsetam [(+/-)-3-(2-thienyl)-2-piperazinone], an antidementia drug, on the Maillard reaction. Tenilsetam inhibited glucose- and fructose-induced polymerization of lysozyme in a concentration-dependent manner in vitro. Reduced enzymatic digestibility of collagen incubated with 100 mM glucose for 4 weeks was also restored to a control level by coincubation with 100 mM tenilsetam. To determine whether tenilsetam inhibits the Maillard reaction in vivo, streptozotocin-induced diabetic rats were treated with tenilsetam (50 mg/kg x day). Elevated levels of advanced glycation end-product-derived fluorescence and pyrraline in renal cortex and aorta of diabetic rats were suppressed by the administration of tenilsetam for 16 weeks. These inhibitory effects of this agent on advanced glycation in diabetic rats suggested its potential therapeutic role in controlling diabetic complications.

Animals↗

Curative percutaneous catheter ablation for various supraventricular and ventricular tachyarrhythmias. Results in 187 consecutive patients during the first five years.

Closed-chest transcatheter electrical ablation (catheter ablation) has been applied to various supraventricular and ventricular tachyarrhythmias as a radical therapeutic technique since its introduction in 1982. Currently, it has become a first line therapy for supraventricular tachyarrhythmias except atrial fibrillation and uncommon types of atrial flutter. We first carried out the ablation procedure in 1991 for the treatment of ventricular tachycardia. Up to February 1997, a total of 187 patients underwent catheter ablation in our institution. The aims of this study are to demonstrate our results of catheter ablation in the early 5 years and to show the usefulness of this new curative method. Successful results were obtained in 168 of 187 patients (overall final success rate: 89.8%). The success rates of each category of tachyarrhythmias were 100/105 patients (95%) with WPW syndrome, 41/46 (89%) with atrioventricular nodal reentrant tachycardia, 7/10 (70%) with atrial flutter, 4/4 (100%) with atrial tachycardia, 2/2 (100%) with medically refractory atrial fibrillation, 13/15 (85%) with idiopathic ventricular tachycardia and 3/7 (43%) with sustained ventricular tachycardia associated with structural heart disease, respectively. Complications that required invasive treatments were observed in 3 patients (2 hemopericardium and 1 complete atrioventricular block). Our results indicate that catheter ablation is highly effective in most categories of tachyarrhythmias and can be applied safely without lethal complications.

Adult↗

Genetic typing of the mouse ob mutation by PCR and restriction enzyme analysis.

A genetic typing method for the mouse obese (ob) mutation by PCR and restriction fragment length polymorphism (RFLP) analysis was developed. Three genotypes (ob/ob, ob/+ and +/+) of the ob mouse are rapidly differentiated with this assay. Since only a small biopsy specimen (tail end) is necessary for the genotyping, the ob mouse at any age is typable and can be used in subsequent breeding or research. Obese homozygotes (ob/ob) were efficiently produced by mating heterozygotes (ob/+) only, which were selected by using the PCR-RFLP assay.

Animals↗

A prospective trial of steroid cessation after renal transplantation in pediatric patients treated with cyclosporine and mizoribine.

We conducted a multi-center prospective study to evaluate the safety and efficacy of steroid withdrawal after renal transplantation in children. In 52 children (51 living-related donor transplants and 1 cadaver donor transplant), immunosuppressive therapy was started with cyclosporine (CyA), mizoribine (MZ), methylprednisolone (MPL) and anti-lymphocyte globulin. Administration of MPL was reduced to alternate days more than 6 months after transplantation, and attempts were made to withdraw it. Acute rejection was noted in 19 patients (36.5%) by 1 month after transplantation. The whole-blood CyA trough level using monoclonal antibody was 175.0+/-17.0 ng/ml in patients who developed acute rejection and 282.0+/-25.3 ng/ml in those who did not show acute rejection (p<0.01). During the 37 attempts at alternate-day MPL administration, clinical acute rejection was observed in only 1 patient and chronic rejection in 3. During 10 attempts to withdraw MPL, acute rejection was noted in 3 patients, but graft function recovered to the pre-rejection level after treatment of the acute rejection. At the last observation, graft function was lost in 3 patients, 22 were receiving MPL on alternate days, and MPL had been withdrawn from 7 for a mean period of 16.7 months. The survival rate of the patients and the grafts was 100% and 94% after an average follow-up period of 4 years. Evaluation of growth showed catch-up growth in all patients during the withdrawal period.

Anti-Inflammatory Agents↗

[Metastatic tumor to the penis from lung and pancreas cancer: report of two cases].

Neoplasms metastasizing to the penis are uncommon, and occur at the end stage of carcinoma. We describe two patients with a metastatic lesion to the penis from lung squamous cell carcinoma and pancreatic adenocarcinoma. We reviewed 101 cases with secondary penile tumor. The prognosis of secondary penile tumor is extremely poor.

Adenocarcinoma↗

Cystatin C measurement and its practical use in patients with various renal diseases.

OBJECTIVE: To evaluate the clinical usefulness in terms of estimation for glomerular filtration rate (GFR), we determined the cystatin C levels in the serum and urine of 33 healthy volunteers as well as in the serum and urine of 35 patients with various renal diseases and compared them with those of creatinine. In addition, we evaluated this substance as an indicator of removal rate of low molecular weight protein with high flux membranes in 6 hemodialysis (HD) patients. METHODS: Serum and urinary cystatin C levels were measured by using an enzyme-linked immunosorbent assay (ELISA) method, 24-hour creatinine clearance was used as an indicator of GFR. RESULTS: Reference intervals with 95% ranges are 0.47-1.03 mg/l in the serum from healthy volunteers. There was a significant positive correlation between serum cystatin C and creatinine levels (r = 0.936, p < 0.001) in the patients with various renal diseases. Serum cystatin C and creatinine inversely and logarithmically correlated to creatinine clearance as shown in the following equations: log cystatin C = -0.564 x log creatinine clearance + 1.216 (r = -0.850), log creatinine = -0.678 x log creatinine clearance + 1.449 (r = -0.904). In these equations l/day is the unit used for creatinine clearance, mg/l is the unit used for serum cystatin C. The range for cystatin C is 0.67-6.15 mg/l, 0.66-7.23 mg/dl for creatinine and 8.9-186.3 l/day (6.2-129.4 ml/min) for creatinine clearance. Serum cystatin C levels started to increase over normal range when creatinine clearance fell below 135.9 l/day (94.4 ml/min), while serum creatinine remained within normal ranges. The daily urinary excretion of cystatin C was increased significantly in the group in which creatinine clearance was below 30 l/day (20.8 ml/min) compared to that in which creatinine clearance was higher than in 70 l/day (48.6 ml/min). Fractional clearance of cystatin C increased proportionally and markedly to the decrease of creatinine clearance. In a regular HD condition with high flux membrane, the cystatin C removal rate was 38.7 +/- 1.7%. CONCLUSIONS: These data suggest that combined measurement of cystatin C in the serum and urine is useful to estimate GFR, especially to detect the mild reduction of GFR. Cystatin C measurement can also be used as an indicator of removal rate of low molecular weight protein with different types of high flux membranes in hemodialysis.

Adult↗

[Rapid identification of four bacterial species by proton magnetic resonance spectroscopy].

In the present study, we applied proton nuclear magnetic resonance (1H NMR) spectroscopy to distinguish between four bacterial species: Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Klebsiella pneumoniae. Because of differences in the composition of their cell wall and cytoplasmic constituents, individual bacterial species exhibited characteristic spectra except for K. pneumoniae. Reproducibility was satisfactory in the quantitative studies for chemical shift, intensity of signal and integrated intensity. The turnaround time of the test was only about 40 minutes. 1H NMR could be a new powerful tool for strain identification.

Escherichia coli↗

Cytochrome P450 species involved in the metabolism of quinoline.

Quinoline is a hepatocarcinogen in rats and mice and a well-known mutagen in bacteria after incubation with rat liver microsomes. The specific cytochrome P450 enzymes involved in quinoline metabolism in human and rat liver microsomes were determined using cDNA-expressed cytochrome P450s, correlations with specific cytochrome P450-linked monooxygenase activities in human liver microsomes and inhibition by specific inhibitors and antibodies. CYP2A6 is the principal cytochrome P450 involved in the formation of quinoline-1-oxide in human liver microsomes (correlation coefficient r = 0.95), but is formed in only minute quantities in rat liver microsomes. CYP2E1 is the principal cytochrome P450 involved in the formation of 3-hydroxyquinoline (r = 0.93) in human liver microsomes and is involved in the formation in rat liver microsomes. A high correlation coefficient (r = 0.91) between CYP2A6 activity and quinoline-5,6-diol formation in human liver microsomes was observed, but this most likely reflects the involvement of CYP2A6 in the formation of quinoline-5,6-epoxide, from which the quinoline-5,6-diol is formed, as conversion of quinoline-5,6-epoxide to quinoline-5,6-diol on incubation of the epoxide with CYP2A6 could not be demonstrated. A cDNA-expressed human microsomal epoxide hydrolase, however, efficiently converted the epoxide to the diol and the microsomal epoxide inhibitor cyclohexene oxide inhibited quinoline-5,6-diol formation in rat liver microsomes. A preliminary kinetic analysis of quinoline metabolism in human liver microsomes was carried out and Eadie-Hofstee plots indicate that the formation of quinoline-5,6-diol is monophasic, while that of quinoline-1-oxide and 3-hydroxyquinoline is biphasic.

Animals↗