Biomedical subjects

Tatsuya Takayama

Publications and source records attributed to Tatsuya Takayama.

17 recordsLinked to original sources

PubMed2007

Evaluation of S100A10, annexin II and B-FABP expression as markers for renal cell carcinoma.

This study aimed to analyze expression of S100A10, annexin II and B-FABP genes in renal cell carcinoma (RCC) and their potential value as tumor markers. Furthermore, any correlation between the gene expression and prognostic indicators of RCC was analyzed. Expression of each gene was estimated by RT-PCR in the non-neoplastic (normal) and tumorous parts of resected kidney samples. Also, each antigen was immunostained in RCC and normal kidney tissues. Expression of the S100A10 gene averaged 2.5-fold higher in the tumor than that in the normal tissues (n = 47), after standardization against that of beta-actin. However, expression of annexin II, a natural ligand of S100A10, was only 1.64-fold higher. In the tissue sections of RCC, S100A10 and annexin II were immunostained in membranes. In the normal renal epithelia, however, both antigens were stained in the Bowman's capsule and the tubules from Henle's loop through the collecting duct system, but not in the proximal tubules, from where most RCC are derived. In contrast, expression of the B-FABP gene was 20-fold higher in the tumor. No B-FABP was immunohistochemically detected in normal kidney sections, but it was stained in the cytoplasm of RCC tissue sections. S100A10 and B-FABP genes were overexpressed regardless of nuclear grade and stage of RCC. Immunopositivity in RCC tissues (n = 13) was 100% for S100A10 and annexin II, and 70% for B-FABP; however, no clear relationship was observed in either antigen with nuclear grade and stage. It was found that all three performed well as RCC markers. B-FABP was most specific to RCC, as it was expressed little in normal kidney tissues.

Annexin A2↗

PubMed2006

High levels of thymidine phosphorylase as an independent prognostic factor in renal cell carcinoma.

BACKGROUND: We investigated whether thymidine phosphorylase (TP) protein level in renal cell carcinoma (RCC) correlates with clinicopathological characteristics and clinical outcomes. METHODS: TP protein level was measured in 116 RCC specimens and in 90 non-neoplastic kidney tissues using a sandwich-type enzyme-linked immunosolvent assay. RESULTS: The median TP protein level in RCC tissues was 9.76-fold (range, 3.2-933.9) higher than those in non-neoplastic kidney tissues (P < 0.0001). TP protein level was correlated with T classification, histological grade and mode of infiltration. TP as a prognostic variable was studied using a logistic regression model. TP at higher levels (128 U/mg protein or greater) would play a role as an independent prognostic factor (odds ratio, 13.73; 95% confidence interval, 2.09-90.41; P = 0.0064). CONCLUSION: TP at high levels can be regarded as an unfavorable independent prognostic factor. These results may pave a way for a novel approach to effective treatment of RCC.

Adult↗

PubMed2006

Retrograde endoscopic management of ureteral stones more than 2 cm in size.

OBJECTIVES: To verify the safety and efficacy of retrograde endoscopic lithotripsy as the treatment modality for large ureteral stones. METHODS: From July 1996 to May 2005, we performed retrograde endoscopic treatment in 54 patients with large ureteral stones more than 2 cm in size, using a small-caliber ureteroscope and a holmium:yttrium-aluminum-garnet laser lithotriptor. Although the mean maximal stone diameter was 2.4 cm, 6 patients had stones measuring larger than 3 cm. Of the 54 patients, 11 had stones that could not be effectively fragmented by shock wave lithotripsy previously. RESULTS: Of the 54 patients, 48 were treated solely using retrograde ureteroscopy. In 47 patients (87%), the stones were fragmented completely by a single endoscopic procedure. Additional shock wave lithotripsy was performed after endoscopic debulking in 2 patients, and any stones remaining in the ureter were easily treated by shock wave lithotripsy. Pyelonephritis resulting from obstruction caused by ureteral stones was observed in 4 patients, 3 of whom required percutaneous nephrostomy and 1 of whom required stent insertion before the endoscopic procedure. These patients then underwent retrograde endoscopic lithotripsy, which completely cleared the calculi in one session. No intraoperative complications occurred. The only postoperative complication was found in 1 patient presenting with a ureteral stricture. One month after the final treatment, no patients had evidence of residual stones. CONCLUSIONS: With use of a small-caliber ureteroscope and a holmium:yttrium-aluminum-garnet laser lithotriptor, retrograde endoscopic lithotripsy seems to be an effective first-line therapy for large ureteral stones measuring more than 2 cm in size.

Adult↗

PubMed2006

Retrograde endoscopic laser therapy and ureteroscopic surveillance for transitional cell carcinoma of the upper urinary tract.

OBJECTIVE: To investigate the efficacy of endoscopic laser therapy and ureteroscopic surveillance for transitional cell carcinoma (TCC) of the upper urinary tract. METHODS: Tumors of the upper urinary tract were detected at ureteroscopy. After TCC was diagnosed by biopsy, retrograde endoscopic laser therapy was performed. Recurrent tumors were treated endoscopically and the patients were followed by ureteroscopic surveillance at 3- to 6-month intervals. RESULTS: Seven patients underwent ureteroscopic treatment. The tumor was grade 1 in five patients and grade 2 in two patients. The average tumor size was 1.3 cm. One patient with large, multifocal tumors died of metastatic disease, and one died of an unrelated cause. One patient requested nephroureterectomy after endoscopic treatment. The remaining four patients were followed up for a mean of 32 months after initial treatment. Each patient received an average of 5.3 ureteroscopic surveillance procedures while 3.3 recurrences on average were detected. Recurrence occurred in all the patients who showed normal radiographic findings. Urine cytology was also of little value in predicting tumor recurrence, except in one patient with carcinoma in situ. The recurrent tumors detected by ureteroscopy were successfully treated by repeated endoscopic procedures. After the follow up, three patients remained alive with no signs indicative of disease, but one patient with an initial grade 2 tumor died of recurrence after 30 months. CONCLUSIONS: Given that ureteroscopic evaluation is essential for surveillance after endoscopic treatment of upper urinary tract TCC because of residual concern about recurrence, patients treated endoscopically should be recommended to undergo long-term endoscopic follow up.

Aged↗

PubMed2006

Effects of calcineurin inhibitors on pharmacokinetics of mycophenolic acid and its glucuronide metabolite during the maintenance period following renal transplantation.

Mycophenolic acid (MPA), the active metabolite of mycophenolate mofetil (MMF) has been introduced into renal transplant immunosuppressant protocols in combination with calcineurin inhibitors (CNIs) and steroids. This study compared the pharmacokinetic profiles of MPA and its major metabolite MPA glucuronide (MPAG) in combination with tacrolimus (TAC) or cyclosporine (CyA) during the maintenance period (>6 months) following renal transplantation. There was no difference between TAC and CyA-treated groups in MPA plasma concentration before drug administration (C(0)). MPA C(0) in TAC and CyA-treated patients did not differ from that in patients who were not treated with a CNI. In patients treated with a CNI, MPAG C(0) was significantly greater in those treated with CyA compared with TAC. The MPAG/MPA ratio in CyA-treated patients was significantly greater than that in the TAC-treated group. We observed that C(0) of MPA was negatively correlated with that of TAC and CyA. Positive correlation between MPA C(0), MPAG C(0) and serum creatinine was stronger in patients treated with CyA compared with TAC. Our study suggests that CyA, but not TAC, inhibits enterohepatic circulation of MPAG as a secondary excretion pathway, and that renal function makes a major contribution to elimination of MPA and MPAG. We indicate that it may be necessary to estimate biliary excretion of MPAG to avoid the risk of intestinal injury in patients receiving combination therapy with TAC during the maintenance period.

Adolescent↗

PubMed2005

Long-term outcome of a low-dose intravesical bacillus Calmette-Guerin therapy for carcinoma in situ of the bladder: results after six successive instillations of 40 mg BCG.

BACKGROUND: In Japan, bacillus Calmette-Guerin (BCG: Tokyo 172 strain) instillation is generally performed at a dose of 80 mg once weekly for eight consecutive weeks; however, many adverse effects including severe ones have been reported. We employed a dose of 40 mg once a week for six consecutive weeks in principle for carcinoma in situ (CIS) of the bladder, and retrospectively evaluated its effectiveness and safety. METHODS: A total of 43 patients with CIS of the bladder were treated by this method and followed-up for a subsequent 12-79 months (median, 54 months). The patients consisted of 35 males and eight females aged 45-87 years (mean, 67.5 years). Intravesical BCG instillation at a dose of 40 mg was conducted once a week for six consecutive weeks. RESULTS: A complete response (CR) was achieved in 84% of the patients, in whom the recurrence-free rate was 72.4% after 3 years and 61.9% after 5 years. The median CR duration was 37.5 months. Two patients underwent total cystectomy, but none died of bladder cancer. As adverse effects, bladder irritation symptoms were observed in 48.8%, pyuria in 46.5%, macroscopic hematuria in 18.6% and fever (>37.5 degrees C) in 9.3%. There were no severe adverse effects requiring discontinuation of drug administration. CONCLUSION: Our present study corroborated both the effectiveness and safety of low-dose BCG therapy for CIS of the bladder. This therapy warrants further study by prospective randomized trials in the future.

Administration, Intravesical↗

PubMed2005

Primary hyperoxaluria type 1 in Japan.

BACKGROUND/AIMS: Current status of primary hyperoxaluria (PH) has not been surveyed in Japan. METHODS: Japanese patients with PH were reviewed in the published literature. RESULTS: Fifty-nine patients were diagnosed as PH from 1962 to 2003. The median ages both at diagnosis and at the onset of initial symptoms were 17 (range: 0.02-63) and 13 (range: 0-58) years, respectively. Twenty-nine (49%) patients were older than 20 years at diagnosis, among whom 26 (90%) already presented end-stage renal failure (ESRF) or soon evolved into ESRF. Among 30 (51%) diagnosed as PH under 20 years old, only 13 (43%) were already in a terminal stage of renal insufficiency. Ten patients were diagnosed as PH1 by liver biopsy. We identified two types of enzymatic phenotypes in 3 of those patients examined. In 1 case, immunoreactive SPT/AGT protein level was very low due to accelerated proteolysis, while in other 2 cases, the immunoreactivity was detected on mitochondria due to mistargeting. Of 9 cases having been subjected to kidney transplantation at a median age of 20 years (range 7.3-40.0), it was only 2 cases that were reported to be successful, while the median survival time of the kidney grafts being 1.4 years (range 0-7). Of 4 patients having undergone combined liver/kidney transplantations (at the ages of 1.3, 1.4, 9 and 41 years, respectively), the surgery was successful in 3 cases; in the remaining one case, however, rejection required removal of the transplanted kidney was observed. The overall survival ratio of all the 59 PH cases accounted for 77, 71 and 55% at 5, 10 and 20 years, respectively. CONCLUSION: Assuming that the majority of the 59 patients with PH reported was classified as PH1, it is postulated that morbidity of violent infantile PH1 in Japan might be less than those in the USA and Europe, and symptoms of elderly Japanese PH1 patients seem to be milder than those of Western patients. Establishment of an early detection system of PH1 and more popular application of combined liver/kidney transplantation deserve further study.

Adolescent↗

PubMed2005

[Interferon-based cytokine therapy for advanced renal cell carcinoma].

Among 126 patients diagnosed with metastatic renal cell carcinoma at Hamamatsu University or its affiliated hospital between 1978 and 2004, pretreatment features associated with a shorter survival in the multivariate analysis were in symptomatic status at diagnosis and in multiple organ metastasis. The 1- and 3-year survival rate in patients with these two prognostic factors were 22.3 and 0.3%, respectively. The style of treatment did not influenced survival in these patients. Therefore, an accurate assessment of their survival benefits both them and physician while it is urgent that we develop novel agents and strategy.

Antineoplastic Agents↗

PubMed2004

BK virus subtype 1 infection associated with tubulointerstitial nephritis in a renal allograft recipient.

The BK polyomavirus (BKV) infects most of the human population, but clinically relevant infections are usually limited to individuals who are in an immunosuppressed state. The significance of BKV infection was investigated in a 50-year-old man who underwent cadaveric kidney transplantation and was treated with tacrolimus, mycophenolate mofetil and prednisolone. By staining renal biopsy specimens with a monoclonal antibody against BK large T antigen, we were able to observe the relationship between the appearance of the BKV antigen and the extent of immunosuppression in this patient. We also determined that BKV belonged to genotype I by analysis of viral DNA from the patient's urine.

BK Virus↗

PubMed2004

[Intravesical Bacillus Calmette-Guerin (BCG: Tokyo 172 strain) instillation for carcinoma in situ of the bladder: results with 6 successive instillations of 40 mg BCG].

We performed a study to evaluate the usefulness of intravesical Bacillus Calmette-Guerin (BCG: Tokyo 172 strain) instillation on carcinoma in situ (CIS) of the bladder. Between 1998 and 2003, 43 patients were treated for CIS of the bladder with a median follow-up period of 45 months (range: 12 to 69 months). The patients (35 males and 8 females) ranged in age from 45 to 89 years (average: 67.5 years). They underwent intravesical instillation of 40 mg of BCG once a week for 6 weeks. A complete response (CR) was achieved in 83.7% of the patients. Among these patients, 97.2% and 70.7% remained recurrence-free during follow up for one year and three years, respectively. The median duration of CR was 31.5 months. Although total cystectomy was performed on 1 patient, none of the patients died of bladder cancer. Adverse effects included bladder irritability in 48.8%, pyuria in 46.5%, gross hematuria in 18.6%, and fever (temperature over 37.5 degrees C) in 9.3%. No clinically significant side effects were observed. These results indicate that intravesical instillation of BCG at a dose of 40 mg given 6 times was as effective as the routine dose of 80 mg, and could decrease systemic adverse effects such as high fever.

Administration, Intravesical↗

PubMed2004

[Economical aspects on the treatments of urolithiasis by surgical methods: comparison of surgical method selections and world status].

Economical elements including surgical fee and hosipital stay become larger in the selection of surgical methods for the treatment of urinary stones. Then, urologists need to explain to patients the treatment cost to obtain informed consent. By comparing the data from participants' answer to Debate 1 at the 82th annual meeting of the Japanese Urological Association (April 2002, Tokyo) and questionnaire responses from the members of the annual meeting of central division of Japanese Urological Association (November 2002, Nagoya), we surveyed the trends of surgical methods on the treatments of staghorn caliculi and lower ureter stones. Furthermore, we clarified the cost of these methods. Based on the status of world countries, we demonstrate the ideal selection including economical aspects on the selection of endourological method.

Global Health↗

PubMed2003

Thymidine phosphorylase and dihydropyrimidine dehydrogenase in renal cell carcinoma: relationship between histological parameters and chemosensitivity to 5-fluorouracil.

OBJECTIVES: Thymidine phosphorylase (TdR-Pase) and dihydropyrimidine dehydrogenase (DPD) are thought to be key enzymes in the metabolic pathway of 5-fluorouracil (5-FU). Theoretically, cancer cells which have high TdR-Pase activity and/or low DPD activity should be sensitive to 5-FU. TdR-Pase is also known to have angiogenic activity which helps tumor progression and metastasis. On the other hand, little is known concerning the relationship of DPD activity with clinical malignant potential in renal cell carcinoma (RCC). In this study, we measured both TdR-Pase and DPD activities in surgically obtained RCC tissues and examined the relationship between these enzymatic activities and histological parameters. In addition, the results of in vitro chemosensitivity testing were also analyzed to determine whether TdR-Pase and/or DPD activity in carcinoma cells can predict the efficacy of 5-FU. METHODS: RCC tissues from 53 patients were obtained. TdR-Pase and DPD activities were measured by ELISA and radioenzyme assay, respectively. Sensitivity to 5-FU was assessed by histoculture drug response assay (HDRA), an in vitro chemosensitivity test, for 20 of the 53 specimens. RESULTS: Both TdR-Pase and DPD activities of RCC increased with histological grade. There was a significant positive correlation between the TdR-Pase activity and 5-FU sensitivity. In addition, a stronger positive correlation was found between TdR-Pase / DPD ratio and 5-FU sensitivity. DPD exhibited no correlation with 5-FU sensitivity. CONCLUSIONS: The activity of both enzymes increased with malignant potential of RCC. TdR-Pase appeared to be the enzyme regulating activation of 5-FU in RCC.

Antimetabolites, Antineoplastic↗

PubMed2003

Primary prostatic endodermal sinus tumor (yolk sac tumor) combined with a small focal seminoma.

We report on a primary endodermal sinus tumor (EST) (yolk sac tumor) combined with a focal seminoma of the prostate occurring in a 24-year-old man. The prostate was widely infiltrated with neoplasms that penetrated the capsule and invaded into the bladder wall and urethra. Most areas of the tumor were composed of papillary and glandular epithelium in the fibrous or myxoid stroma. Schiller-Duval bodies and periodic acid-Schiff-positive hyaline bodies were focally present. In addition to yolk sac tumor, solid nests of seminoma were found in some areas. Immunohistochemistry using specific antibodies for alpha-fetoprotein and cytokeratin showed positive reaction on the EST portion, and placental alkaline phosphatase revealed positive staining in the seminoma portion and a part of EST. Tumor cells exhibited negative staining for prostate-specific antigen, prostatic acid phosphatase, carcinoembryonic antigen, vimentin, chromogranin A, and human chorionic gonadotropin. Despite radical surgery and ordinary cisplatin-based chemotherapy, the patient died 8 months after operation. At autopsy, only EST elements had metastasized to the lungs, liver, and brain, and no tumors were found in either testis. To our knowledge, this is the first reported case of a primary EST combined with a focal seminoma in the prostate.

Adult↗

PubMed2003

Control of oxalate formation from L-hydroxyproline in liver mitochondria.

Serine:pyruvate/alanine:glyoxylate aminotransferase (SPT/AGT) is largely located in mitochondria in carnivores, whereas it is entirely found within peroxisomes in herbivores and humans. In rat liver, SPT/AGT is found in both of these organelles, and only the mitochondrial enzyme is markedly induced by glucagon. Although SPT/AGT is a bifunctional enzyme involved in the metabolism of both L-serine and glyoxylate, its contribution to L-serine metabolism is independent of mitochondrial or peroxisomal localization (Xue HH et al., J Biol Chem 274: 16028-16033, 1999). Therefore, the species-specific and food habit-dependent organelle distribution might be required for proper metabolism of glyoxylate at the subcellular site of its formation. Glyoxylate formation from glycolate and that from L-hydroxyproline have been shown to occur in peroxisomes and mitochondria, respectively. The present study found that urinary excretion of oxalate was markedly increased when a large dose of L-hydroxyproline or glycolate was administered to rats. Oxalate formation from L-hydroxyproline but not that from glycolate was significantly reduced when mitochondrial SPT/AGT had been induced by glucagon. The hydroxyproline content of collagen is 10 to 13%, and collagen accounts for about 30% of total animal protein; therefore, these results suggest that an important role of mitochondrial SPT/AGT in carnivores is to convert L-hydroxyproline-derived glyoxylate into glycine in situ, preventing undesirable overflow into the production of oxalate.

Animals↗

PubMed2003

[Laparoscopic adrenalectomy using telementoring system].

We report on our experience in telementoring during laparoscopic adrenalectomy. An experienced laparoscopic surgeon supervised a less experienced surgeon from a control room about 100 meter away. Mentoring was accomplished over a fiber optic cable employing real-time video imaging, two-way audio communication, OES ImageTrac Video System used to control the laparoscopic image, and a telestrator. The patient was a 52-year-old male with primary aldosteronism due to a left adrenal adenoma 2 cm in diameter. The procedure was successfully performed in 195 minutes with minimal blood loss. The patient recovered without complications and returned home on postoperative day 7. As broadband telecommunication expands, telementoring will become an important method for the training and supporting of laparoscopic surgery.

Adrenalectomy↗

PubMed2002

Thymidine phosphorylase activity in renal cell carcinoma: relationship between histological parameters and chemosensitivity to fluorouracil-related drugs.

Thymidine phosphorylase (TdR-Pase) is an essential enzyme in the metabolism of fluorouracil-related drugs and is also a potent angiogenic factor. We measured the TdR-Pase activity in human renal cell carcinomas (RCCs) to assess the relationship between TdR-Pase activity and the degree of tumor malignancy. We also investigated the relationship between TdR-Pase activity and chemosensitivity to fluorouracil-related drugs. A total of 61 RCC tissue specimens and 39 normal kidney tissue specimens were obtained. TdR-Pase activity was measured by enzyme-linked immunosorbent assay. The in vitro histoculture drug response assay was also performed to examine tumor sensitivity to 5-fluorouracil (5-FU) and doxifluridine (5'-DFUR). The TdR-Pase activity of RCCs was 13-fold that of the normal tissues. Activity increased with histological grade, and,was significantly higher in high-stage tumors (T3 or higher). TdR-Pase activity exhibited a significant positive correlation with sensitivity to 5-FU and 5'-DFUR. High TdR-Pase activity in human RCC was confirmed to predict high tumor grade and stage. RCCs with high TdR-Pase activity were also sensitive to FU-related drugs.

Antimetabolites, Antineoplastic↗

PubMed2002

[Repeat prostate biopsy in patients with previous negative biopsies].

We retrospectively analyzed the results of 104 patients who underwent a second prostate needle biopsy. Between January 1993 and September 2000, 654 needle biopsies were performed and cancer was found in 239 patients. Among the other 415 patients, 104 patients underwent a second biopsy. The average prostate specific antigen (PSA) value was 9.6 ng/ml (2.0-30.9) (Tandem R conversion value). Cancer was detected in 16 out of 104 cases (15%) at the second biopsy, 4 out of 39 (10%) at the third biopsy, and 3 out of 10 (30%) at the fourth biopsy. The age, PSA value, digital examination, echography, and magnetic resonance imaging (MRI) were not helpful in distinguishing the patients with prostate cancer and atypical histological findings at the previous biopsy were the most important information. Among the 9 patients who showed atypical findings at the previous biopsy, 6 (67%) had cancer.

Aged↗