Search PubMed⌕ Search

Biomedical subjects

Akinori Sato

Publications and source records attributed to Akinori Sato.

9 recordsLinked to original sources

Clinicopathological features predicting nodal metastasis of testicular seminoma: results from 100 cases in a single institute.

BACKGROUND/AIMS: To investigate the clinical and pathological features which predict nodal metastasis and/or the prognosis of testicular seminoma and to evaluate the current treatment strategy in a single institute. METHODS: We retrospectively analyzed 100 patients who had been pathologically diagnosed as having testicular seminoma in our institute. Ninety-one patients (91%) had stage I disease, 9 patients (9%) were stage II and none stage III. The median follow-up was 63.2 months (range 0.5-249). RESULTS: The duration between the tumor recognition and the first outpatient visit ranged from 0 to 144 weeks, with a median of 5 weeks, which did not influence the clinical stage. The tumor diameter and the preoperative serum lactate dehydrogenase (LDH) level were the significant predictors of stage II disease. Following orchiectomy, 68 patients (74.7%) with stage I disease received radiotherapy. Only 1 patient who had not received adjuvant radiotherapy died from the recurrent disease. The 5-year survival was 100% for the irradiation group but 95% for the surveillance group, although the difference was not statistically significant. All the stage II patients were successfully treated with chemotherapy following orchiectomy. CONCLUSION: The maximum tumor diameter and the preoperative serum LDH level were the significant predictors of nodal metastasis. Adjuvant radiotherapy in patients with stage I seminoma did not influence the survival. Systemic chemotherapy promised good survival for the seminoma, even with nodal metastasis, in this series. Our results support the good prognosis of testicular seminoma with the current treatment strategy.

Adult↗

Decrease in amplitude of intracardiac ventricular electrogram and inappropriate therapy in patients with an implantable cardioverter defibrillator.

Intracardiac electrograms are important for discrimination of tachyarrhythmia by implantable cardioverter defibrillators (ICD). A low R-wave can cause not only undersensing of ventricular tachyarrhythmia but also inappropriate discharges due to oversensing of unexpected signals because of its characteristic sensing algorithm. Therefore, this study aimed to investigate adverse events associated with R-wave amplitude. We included 115 consecutive patients followed-up over one year after implantation of a transvenous ICD system. The status of the ICD was checked every 3 months and intracardiac ventricular electrograms were analyzed. The decrease in R-wave amplitude was high in arrhythmogenic hypertrophy cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy (ARVC), and sarcoidosis. Low R-waves (< 5.0 mV) were observed in 13 patients at a follow-up of 15 +/- 16 months after implantation, and the mean R-wave was 3.0 +/- 0.8 mV. The frequency of low R-waves was high in ARVC (38%), sarcoidosis (33%), and dilated cardiomyopathy (17%). All of the dilated cardiomyopathy patients with low R-waves had severe left ventricular dysfunction. Inappropriate ICD therapy resulting from T-wave oversensing occurred in 7 patients and the R-wave was < 5.0 mV in 6 of the patients. The frequency of inappropriate therapy was high in patients with sarcoidosis. In 3 patients, inappropriate therapy caused ventricular tachyarrhythmia. In conclusion, decreases in R-wave amplitude occurred in some progressive cardiac disorders and caused inappropriate ICD discharges having arrhythmogenicity. Physicians should attempt to obtain a high R-wave amplitude during ICD implantation and careful follow-up is required, especially in patients with ARVC or sarcoidosis.

Adult↗

Survivin associates with cell proliferation in renal cancer cells: regulation of survivin expression by insulin-like growth factor-1, interferon-gamma and a novel NF-kappaB inhibitor.

Although survivin has been widely recognized as an attractive target for cancer therapy, the exact mechanism regarding the regulation of survivin and its effect on cell proliferation have yet to be clearly defined in renal cell carcinoma (RCC). We investigated herein the association between survivin expression and cell proliferation in a RCC cell line, KU19-20. In KU19-20 cells, cell proliferation and survivin expression were significantly induced by IGF-1, whereas they were inhibited by a novel NF-kappaB inhibitor dehydroxymethyl-epoxyquinomicin (DHMEQ) and IFN-gamma. The combination of DHMEQ and IFN-gamma inhibited cell proliferation synergistically with a pronounced attenuation of survivin expression. Furthermore, treatment with survivin-specific siRNA reduced expression of survivin and significantly inhibited cell proliferation. Survivin expression was thus associated with cell proliferation in KU19-20 cells. The regulation of survivin by IFN-gamma and/or an NF-kappaB inhibitor may therefore be a potential treatment modality for RCC.

Benzamides↗

Hydrosilylation of alkynes with a cationic rhodium species formed in an anionic micellar system.

[reaction: see text] Rhodium-catalyzed hydrosilylation of alkynes in an aqueous micellar system has been developed. A combination of [RhCl(nbd)](2) and bis(diphenylphosphino)propane (dppp) effects (E)-selective hydrosilylation in the presence of sodium dodecyl sulfate (SDS) in water. The (E)-selectivity strongly indicates the formation of a cationic rhodium species via dissociation of the Rh-Cl bond by the action of anionic micelles. The addition of sodium iodide provided (Z)-alkenylsilanes predominantly.

Journal Article↗

Life-threatening serotonin syndrome in a patient with chronic heart failure and CYP2D6*1/*5.

We report a case of serotonin syndrome that occurred in a patient with chronic heart failure associated with a panic disorder. The 39-year-old Japanese man had been treated with paroxetine at 20 mg/d for 1 1/2 years. He presented with rhabdomyolysis, renal failure, fulminant liver failure, cardiac conduction disturbance, and disseminated intravascular coagulation, as well as conventional symptoms of serotonin syndrome including alterations in cognition (disorientation, confusion) and behavior (restlessness), autonomic nervous system dysfunction (fever, shivering), and abnormal neuromuscular activity (ataxia, hyperreflexia, myoclonus). All medications prescribed before hospital admission were discontinued. After 24 hours of continuous venovenous hemofiltration, diuresis resumed and renal and liver function improved rapidly. Disorientation, restlessness, hyperreflexia, and myoclonus abated slowly over the next 72 hours. The patient's anxiety subsided more slowly, and he recovered completely 1 week later. The plasma concentration of paroxetine was elevated far above the upper limit of the therapeutic range. The patient had cytochrome P-450 (CYP) 2D6*1/*5, a heterozygosity of an inactivated allele of CYP2D6, which metabolizes paroxetine. The patient was determined to be an intermediate metabolizer who was potentially vulnerable to paroxetine, a major inhibitor of CYP2D6. Heart failure is often accompanied by psychiatric disorders. A wide range of drugs commonly prescribed for these conditions, including beta-blockers, antiarrhythmics, and antidepressants, are metabolized by CYP2D6. Genetic screening for CYP2D6 in patients with these conditions may prevent life-threatening drug intoxication.

Adult↗

[Beneficial biventricular pacing in a patient with cardiac sarcoidosis and refractory heart failure: a case report].

A 54-year-old woman had been treated under a diagnosis of cardiac sarcoidosis since 1998. She was admitted to our department because of recurrent heart failure in April 2002. A DDD pacemaker was implanted because of complete AV block in 2000, but she had always suffered from > or = New York Heart Association (NYHA) class III heart failure. To prevent recurrent heart failure, biventricular pacing was performed. The left ventricular epicardial pacing lead was newly inserted into the great cardiac vein via the left subclavian vein, and connected with the previously implanted generator. The QRS duration decreased from 200 to 140 msec. Serum brian natriuretic peptide level decreased from 321 to 226 pg/ml. Cardiac index increased from 1.93 to 2.20. Her functional class improved from NYHA class III to class II.

Cardiomyopathies↗