Biomedical subjects

Tetsuro Kato

Publications and source records attributed to Tetsuro Kato.

At least 55 records · Page 3Linked to original sources

PubMed2003

Association of V89L SRD5A2 polymorphism with prostate cancer development in a Japanese population.

PURPOSE: The SRD5A2 gene codes the steroid 5-reductase type II, a critical mediator of androgen action, and the V89L and A49T polymorphisms of this gene may be associated with a distinct enzyme activity. We explored the association among these polymorphisms and the risk of prostate cancer or benign prostatic hyperplasia (BPH) in a Japanese population. MATERIALS AND METHODS: This study included 302 patients with prostate cancer, 228 with BPH and 243 male controls. V89L and A49T polymorphisms were analyzed by the polymerase chain reaction restriction fragment length polymorphism method. Genotypes were evaluated by electrophoresis on agarose gel. RESULTS: For the V89L polymorphism there were no significant differences in genotype frequencies in patients with prostate cancer and controls (p = 0.071) or in patients with BPH and male controls (p = 0.219). However, males with the VV or VL genotype were at significantly increased risk for prostate cancer compared with those with the LL genotype (adjusted OR 1.69, 95% CI 1.07 to 2.65, p = 0.024). The risk of BPH in males with the VV or VL genotype was not significantly elevated in comparison with those with the LL genotype (adjusted OR 1.37, 95% CI 0.85 to 2.20, p = 0.194). The V89L variant was not associated with the grade or stage of prostate cancer, or with patient age. For the A49T polymorphism all subjects had the AA genotype. CONCLUSIONS: The V allele of the V89L polymorphism in the SRD5A2 gene may dominantly increase the risk of prostate cancer.

Aged↗

PubMed2003

Chronopharmacokinetics of tacrolimus in kidney transplant recipients: occurrence of acute rejection.

The circadian variation of clinical pharmacokinetics of tacrolimus was studied using 16 adult renal transplant recipients 1 month after the operation. The recipients were administered tacrolimus twice a day (9 a.m. and 9 p.m.), and whole-blood samples were obtained just prior to and 1, 2, 3, 6, 9, and 12 hours after oral administration. Histological specimens of transplant kidney were collected by an allograft core biopsy on day 28 after the transplantation. There were no circadian changes in the area under the concentration-time curve (AUC0-12) (214 ng.h/mL during daytime vs. 223 ng.h/mL during nighttime) resulting from morning and night doses. A slight delay in mean residence time (MRT0-12) and time to the peak concentration (tmax) was found after night doses, but there was no statistical significance. Three patients (18.8%) had a clinical acute rejection (AR) episode 4 to 6 weeks after transplantation, and AUC0-12 at nighttime was significantly lower (18.4% on average) in patients with AR in comparison to those without AR. There was no statistical significance in maximum concentration (Cmax) or morning/night trough levels between patients with and without AR. In regard to the correlation between tacrolimus concentrations in each sampling time and AUC0-12, the morning trough concentrations were less predictable for daytime AUC0-12 (r2 = 0.125), but there was a weak correlation to nighttime AUC0-12 (r2 = 0.424). Tacrolimus concentrations at 2, 3, and 6 hours after the morning dose (C2, C3, and C6) had a good correlation against daytime AUC. The results of this study indicate that the variance on the clinical pharmacokinetics of tacrolimus between daytime and nighttime in renal transplant patients is not significant, while the lower nighttime AUC corresponded to the occurrence of AR.

Adult↗

PubMed2003

[Acceleration of ATP-induced contraction in the obstructed bladder of the rat].

BACKGROUND: Detrusor instability is one of the most common problems in patients with lower urinary tract obstructive diseases, such as benign prostatic hyperplasia. Adenosine triphosphate (ATP) has been associated as a neuronal component in the detrusor instability. MATERIALS AND METHODS: Ninety-six female Splague-Dawley rats were studied. Outflow obstructions were created by ligature of the urethra over which a catheter was placed. Changes in the bladder capacity, and an isovolumetric contractile response to pharmacologic antagonists were studied in the obstructed rats for a period of from one day to four weeks. RESULTS: The bladder capacity of rats obstructed for four weeks increased significantly. Maximum bladder contraction pressure with the use of atropine medication was inhibited in 60 percent and, 30 percent of in the control group, respectively. The inhibitory effect of the maximum bladder contraction pressure by the pyridoxalphosphate-6-azophenyl-2', 4'-disulphonate (PPADS) dosage after the atropine dosage was not recognized it in the control group, but the effect was recognized powerfully in the obstructed group. CONCLUSION: In the obstructed bladder rat, strong rise of the bladder contraction by P2X receptor with a lower urinary obstruction was accepted, and that result reflects positively. Therefore, it was guessed that the result was an end of the compensatory mechanism of unstable bladder.

Adenosine Triphosphate↗

PubMed2003

[A case of renal cell carcinoma in tuberous sclerosis].

A 43-year-old woman with mental retardation, epilepsy, and urinary stone disease had a right renal tumor. Acne-like anthema around the nose and dental pits of the nine teeth were typical signs of tuberous sclerosis (TSC), and the biopsy finding of the facial anthema was consistant with TSC. The pathological diagnosis of laparoscopic nephrectomy was renal cell carcinoma in the hemorrhagic cyst. The TSC-related renal cell carcinoma tends to develop bilaterally in younger individuals compared with the sporadic RCC. This case is the 27th case of TSC-related RCC in Japan.

Adult↗

PubMed2003

[Pituitary stalk metastasis from lung cancer, preceding diabetes insipidus--case report and clinical review of the literature].

A 59-year-old woman whose first clinical manifestations were polyuria and polydipsia was admitted to our hospital. Brain MRI showed multiple mass lesions and a thickened pituitary stalk. Chest CT showed hilar and mediastinal lymphadenopathy and a small nodule measuring about 1.5 cm in the apex of the right lung. Histopathological examination revealed adenocarcinoma of the lung, and primary lung cancer with diabetes insipidus secondary to pituitary stalk metastasis was diagnosed. She received systemic chemotherapy and whole-brain irradiation concurrent with intranasal desmopressin (DDAVP) treatment. Although the size of the tumor was reduced, her symptoms did not improve and the same dose of hormone replacement therapy was required. We present this rare case and review the twenty cases of metastatic pituitary lesions arising from lung cancer reported in the literature.

Adenocarcinoma↗

PubMed2002

Natural killer cells attack tumor cells expressing high levels of sialyl Lewis x oligosaccharides.

Epithelial carcinoma and leukemia cells express sialyl Lewis x oligosaccharides as tumor-associated carbohydrate antigens. To determine the role of sialyl Lewis x oligosaccharides in tumor dissemination, human melanoma MeWo cells, which do not express sialyl Lewis x, were transfected with alpha1,3-fucosyltransferase III (FTIII), and cell lines expressing different amounts of sialyl Lewis x were isolated. When these cells were injected into the tail vein of nude mice, cells expressing moderate amounts of sialyl Lewis x (MeWo-FTIII.M) produced a significantly greater number of lung tumor foci than did parental MeWo cells. In contrast, cells expressing large amounts of sialyl Lewis x (MeWo-FTIII.H) produced few lung tumor foci in nude mice but were highly tumorigenic in beige mice, which have defective natural killer (NK) cells. In vitro assays demonstrated that MeWo-FTIII.H cells are much more sensitive to NK cell-mediated cytotoxicity than are MeWo-FTIII.M cells or parental MeWo cells and the susceptibility of MeWo-FTIII.H cells to NK cell-mediated cytolysis can be inhibited by preincubating MeWo-FTIII.H cells with anti-sialyl Lewis x antibody. Moreover, we discovered that NK cell-mediated cytolysis of MeWo-FTIII.H cells can be inhibited by the addition of an antibody against the NK cell receptor CD94 or sialyl Lewis x oligosaccharides. These results, combined with structural analysis of MeWo-FTIII.H cell carbohydrates, indicate that moderate amounts of sialyl Lewis x lead to tumor metastasis, whereas expression of high levels of sialyl Lewis x leads to an NK cell attack on tumor cells, demonstrating that expression of different amounts of sialyl Lewis x results in entirely different biological consequences.

Animals↗

PubMed2002

No association between HER-2 gene polymorphism at codon 655 and a risk of bladder cancer.

The amplification and overexpression of the human epidermal growth factor receptor 2 gene HER-2 (also known as c-erb-B2 or neu) have been shown to be associated with bladder cancer and its progression. Recent studies indicated an association between the Ile to Val polymorphism at codon 655 of HER-2 and susceptibility to breast cancer. To investigate the correlation between the Ile/Val polymorphism and the susceptibility and progression of bladder cancer, we analyzed the polymorphism in 232 patients with transitional cell carcinoma of the bladder and 408 normal controls. The frequencies of the Ile/Ile, Ile/Val and Val/Val genotype were 75.9%, 21.6% and 2.6%, respectively, in patients with bladder cancer and 75.7%, 23.0% and 1.2%, respectively, in controls. Statistical analyses of the genotype prevalence showed no significant difference between bladder cancer patients and normal controls (p = 0.419). Moreover, no significant differences in the genotype prevalence were observed when the patients were stratified according to the tumor grade, stage and smoking habits. When the Ile/Ile genotype was compared to the Ile/Val and Val/Val genotypes, a significant difference was found only between the patients with tumor stage Ta and those with T1-4 (age, gender and smoking habits-adjusted odds ratio = 2.13, 95% confidence interval = 1.09-4.15, p = 0.027). When the Ile/Ile + Ile/Val genotypes compared to the Val/Val genotype, no significant findings were observed. These results suggested that the HER-2 polymorphism at codon 655 is unlikely to be associated with the onset of bladder cancer. Furthermore, the findings suggest no association between this polymorphism and the disease progression in bladder cancer, although the possibility remains that the Ile/Ile genotype may be related to an increased risk of disease progression.

Aged↗

PubMed2002

Correlation of initial PSA level and biopsy features with PSA-doubling time in early stage prostate cancers in Japanese men.

OBJECTIVE: To distinguish good candidates for watchful waiting from those who need immediate treatment in localized prostate cancer. METHODS: Prostate specific antigen (PSA)-doubling time (DT) was calculated by a log-linear regression model for 78 patients with clinically localized prostate cancer (T1c: 47, T2a: 6, T2b: 21, and T3: 4) under surveillance. Median observation period was 37.5 months. The first 1-year PSA-DT was compared with the overall PSA-DT in 41 patients who had been under surveillance for more than 3 years. RESULTS: There was significant difference in the PSA-DT distribution between a pooled group of T1c and T2a and a group of T2b and T3 patients (median 58.8 versus 33.3 months, P = 0.0052). A combination of three parameters consisting of initial PSA level less than 10 ng/ml, WHO grade 1, one or two positive core per six to eight systematic biopsy cores with 50% or less cancer involvement significantly correlated with PSA-DT distribution in the T1c plus T2a group (P = 0.0034). The first year assessment of PSA-DT was identical to the overall assessment in 48.8%, 2 years or more in 36.6%, while it was 2 years or less (possibly over-estimated) in 14.6%. CONCLUSION: PSA-DT can be predictable to some extent with the initial PSA level and biopsy features in early stage prostate cancers. Prospective study is needed to clarify whether temporary observation together with PSA-DT estimation is a safe strategy and is complementary to clinico-pathological parameters at diagnosis.

Adenocarcinoma↗

PubMed2002

Health-related quality of life of ileocecal rectal bladder compared with ileal conduit diversion: a questionnaire survey.

BACKGROUND: The ileocecal rectal bladder (IRB) after cystectomy has been devised, in which continence is controlled by the anal sphincter. To assess how this procedure influences postoperative health-related quality of life (QOL), IRB patients were compared with ileal conduit (IC) patients using a questionnaire mail-out. METHODS: The questionnaire consisted of 35 questions. The questions were multiple choice and the answers were rated on a Linkert rank-type four-point scale. The IRB operation was performed on 29 patients between March 1990 and July 1998. The questionnaire was mailed to 21 of 29 IRB and 34 IRC patients, who underwent either operation during the same period abd had no persistent or recurrent tumor. Statistical analysis was performed by Mann-Whitney U-test. RESULTS: All 21 IRB patients (100%) and 24 IC patients (71%) responded to the questionnaire. The mean age and follow-up time of both groups were not significantly different. The IRB group had better scores in many items, especially, in those of self-care, turning over freely during sleep,and tension. However, 43% of IRB patients used pads for small amounts of incontinence (spotting) and worried about flatus. CONCLUSION: These findings show that many functional and symptomatic health related QOL scores are better after IRB and support the use of this procedure of urinary diversion for selected patients.

Adult↗

PubMed2002

Cyclin D1 gene polymorphism is associated with an increased risk of urinary bladder cancer.

Cyclin D1 is believed to play an important role in the genesis and/or progression of transitional cell cancer (TCC) of the urinary bladder. Cyclin D1 gene (CCND1) mRNA is alternatively spliced to produce two transcripts, and the splicing pattern may be modulated by a G to A single nucleotide polymorphism within the splice donor site of exon 4. This study was conducted to explore the association between the polymorphism and the susceptibility to and disease status of TCC of the bladder in 222 cases and 317 native Japanese controls. The relationship between the CCND1 polymorphism and the mRNA splicing pattern in TCC cells was evaluated by semi-quantitative reverse-transcription PCR. The CCND1 A allele was more frequently observed in the TCC group than the control group (P = 0.032) with a significant difference in the genotype frequency between the two groups (P = 0.029). The AA genotype was associated with a significantly higher risk of TCC compared with the AG+GG genotypes (adjusted odds ratio (aOR) = 1.76, 95% confidence interval (CI) = 1.09-2.84, P = 0.022). This association was observed more significantly in nonsmoking cases (aOR = 2.53; 95% CI = 1.28-4.51, P = 0.008). Looking at tumor grade, the presence of the A allele was associated with higher grade (= grade 3) tumors with a gene dosage effect (aOR = 1.77, CI = 1.16-2.69, P = 0.008). In tumor stage, although not significant, the AA + AG genotypes tended to be more frequently observed in cases with T1-4 tumors than those with Ta tumors (aOR = 1.94, 95% CI = 0.98-3.82, P = 0.057). The genotype seemed to influence the two alternatively spliced forms of the CCND1 mRNA because the ratio of the CCND1 transcript-b/transcript-a was significantly higher in cases with the AA genotype compared with those with the AG + GG genotypes. These data suggest that the CCND1 variant A allele may be associated with an increased risk of TCC of the bladder, especially in men without a history of smoking, and it may also have an effect on its disease status.

Age Factors↗

PubMed2002

Glomerular endothelium exhibits enhanced expression of costimulatory adhesion molecules, CD80 and CD86, by warm ischemia/reperfusion injury in rats.

Recent studies suggested that the vascular endothelial cells function as a resident antigen-presenting cell (APC) in certain situations such as organ transplantation, and the ischemia/reperfusion injury, an inevitable event in organ transplantation, leads to an enhanced biosynthesis of cell adhesion molecules. We have demonstrated that the hepatic sinusoidal endothelial cells have potential ability as APCs by expressing the costimulatory adhesion molecule proteins, CD80 (B7-1) and CD86 (B7-2), of which expression was enhanced by warm ischemia/reperfusion of the rat liver. In this study, we assessed the localization of CD80, CD86, and intercellular adhesion molecule 1 in the rat kidneys and the influence of warm ischemia/reperfusion with or without a hypercreatinemic condition on the expression of these adhesion molecules in the renal tissues. Wistar male rats weighing 150 to 230 g were divided into group A, receiving a sham-operation (control), group B, receiving 1-hour clamping of the left renal pedicle (temporary ischemia), and group C, receiving right nephrectomy and 1-hour clamping of the left renal pedicle (temporary ischemia with hypercreatinemia). The left kidneys were submitted to immunohistochemical and molecular analyses sequentially for the period of 14 days. We found that CD80, CD86, and intercellular adhesion molecule 1 proteins localized on the glomerular and peritubular endothelium and were up-regulated after ischemia/reperfusion. The up-regulation of these three proteins was enhanced by the hypercreatinemic condition. The relative mRNA levels analyzed by real-time reverse transcription polymerase chain reaction showed that CD80 and CD86 expressions were constitutively observed and significantly increased for 14 days after the warm ischemia reperfusion with a peak level at Day 3 (6.7- and 20.8-fold increase for CD80 and CD86, respectively). Our results suggested that the glomerular endothelial cells will play a pivotal role as a APC by expressing CD80 and CD86 in the induction of renal tissue injury associated with the ischemia/reperfusion at renal transplantation surgery, as well as the peritubular endothelium.

Animals↗

PubMed2002

A case of solid pseudopapillary neoplasm of the pancreas and tumor doubling time.

BACKGROUND: Solid pseudopapillary neoplasm of the pancreas is a rare tumor with unique clinicopathological features. Although it is considered to grow slowly, little is known about its doubling time. METHOD: We encountered a young Japanese woman with a solid pseudopapillary neoplasm of the pancreas that had been detected at another hospital 5 years previously but was resected at our hospital. The tumor showed only a solid component without any cysts. Computed tomographic scans taken 5 years apart were compared to determine the tumor doubling time. RESULT: The tumor doubling time according to the formula of Schwartz and co-workers was determined to be 765 days. CONCLUSION: These findings confirm that this tumor grows quite slowly and also support long disease-free periods even in patients who have recurrence or metastases.

Adult↗

PubMed2002

Single nucleotide polymorphisms in the 3' untranslated region of vascular endothelial growth factor gene in Japanese population with or without renal cell carcinoma.

We investigated native Japanese subjects whether C702T, C936T and G1612A polymorphisms in the 3' untranslated region (3'-UTR) of vascular endothelial growth factor (VEGF) gene are associated with the risk of renal cell carcinoma (RCC). Genomic DNAs from 145 RCC patients and 145 healthy controls were examined by polymerase chain reaction-based restriction fragment length polymorphism. Variant allele frequencies of C702T, C936T and G1612A were 0.00, 0.20 and 0.13 in the controls, respectively. The C702T and G1612A allele frequencies were significantly different between the Japanese population and the Caucasian population reported elsewhere. For each of C936T and G1612A polymorphisms, there was no statistically significant difference in the distribution of genotype frequencies between the cases and controls. Odds ratios and 95% confidence intervals computed by logistic regression analyses were not statistically significant. Stratification for the RCC cases according to pathological cell subtype, grade or stage failed to reveal any significant heterogeneity with respect to the genotype of each VEGF polymorphism. We revealed that there are significant ethnic differences in the C702T and G1612A allele frequencies, but suggested that C702T, C936T and G1612A polymorphisms in the 3'-UTR of VEGF gene are not associated with the risk of RCC, at least in Japanese population.

3' Untranslated Regions↗

PubMed2002

[Upregulation of costimulatory adhesion molecule (CD80) in rat kidney with ischemia/reperfusion injury].

PURPOSE: Ischemia/reperfusion injury associated with organ transplantation affects early graft function and acute rejection. Recently, it has been suggested that ischemic insult increases the immunogenicity of the organ. The purpose of this study was to determine the expression of a cell adhesion molecule, CD80, which plays an important role in the costimulatory pathway for full T-cell activation in organ transplantation. MATERIALS AND METHODS: Wistar male rats weighing 150-180 g were divided into control group and ischemia groups with temporary clamping of the left renal artery for 30, 60 and 180 minutes. The left kidneys obtained at 1 hour, 1, 3, 7 and 14 days after reperfusion were subjected to total RNA extraction followed by reverse transcriptase-PCR (RT-PCR), fluorescence immunostaining and histological staining. RESULT: The expression of CD80 by RT-PCR was not observed in the control group, but was observed in the ischemia groups from 1 to 14 days after reperfusion. Fluorescence immunostaining of CD80 was positive in the ischemia groups, but not in the control group. CD80 expression was detected mainly in the endothelium of the glomeruli and the peritubular vessels. CONCLUSION: These results indicate that CD80 is upregulated by ischemic insult, and that the costimulatory pathway may be enhanced by ischemia/reperfusion injury without alloantigens.

Animals↗

PubMed2002

[The effects of the antagonists of muscarinic acetylcholine receptor subtypes in rat brain on urinary bladder contraction].

BACKGROUND: Pontine micuturition center and storage center are controlled by upper brain. Pharmacological and molecular biological data indicate the distribution of muscarinic receptor subtypes in rat brain, however, the effect of central muscarinic cholinergic mechanisms on the bladder activity has not been evaluated. We investigated the diversity of effect of each subtype in rat brain. METHODS: The muscarinic agents such as muscarine (non-specific agonist), atropine (non-specific antagonist), pirenzepine (M1 receptor antagonist), AF-DX116 (M2 receptor antagonist) and 4-DAMP (M3 receptor antagonist) were administrated with intracerebroventricular injection (I.C.V. group) or intravenous injection (i.v. group). The drug effects on rhythmic bladder contraction were investigated. RESULTS: In I.C.V. group, the bladder contraction pressure were reduced by atropine, pirenzepine and 4-DAMP. The contraction time were shortened by pirenzepine and 4-DAMP but extended by AF-DX116. The contraction frequency was decreased by AF-DX116. Whereas AF-DX116 in i.v. group reduced the contraction pressure but did not cause any changes of the contraction time and the frequency. Other agents in i.v. group had same tendency with those of I.C.V. group except for intensity. CONCLUSION: That is to say AF-DX116 in I.C.V. group facilitate both micuturition center and storage center. In other words, these data indicate M2 receptor in rat brain inhibits both micurition and storage center. In addition, the effect of AF-DX116 in brain suggests that the development of new drug which proceed to central neuron system might provide a new treatment of neurogenic bladder.

Animals↗

PubMed2002

[Rapidly growing renal angiomyolipoma during pregnancy with tumor thrombus into the inferior vena cava: a case report].

A case of renal angiomyolipoma rapidly growing during pregnancy with tumor thrombus into the inferior vena cava is reported. Angiomyolipoma in a 31-year-old woman was incidentally found by ultrasonography. CT scan revealed a fat-containing tumor in the right kidney with 4 cm in diameter. The patient was followed at outpatient clinic without any treatment. Fifteen months later, the post-delivery follow-up CT scan showed that tumor size had grown up to 11 cm in diameter. Although laparoscopic right nephrectomy was tried, open transperitoneal right nephrectomy was performed because the tumor thrombus extending into the inferior vena cava was found during the laparoscopic procedure. Pathological diagnosis was angiomyolipoma of the kidney. There are several reports that indicate angiomyolipoma grows rapidly during pregnancy. Our case demonstrates that careful follow-up is required for angiomyolipoma in women with possible conception and delivery.

Adult↗

PubMed2002

[A case of long-term remission with salvage surgeries for chemotherapy-resistant germ cell tumor of testis].

A patient with non-seminomatous germ cell tumor of testis underwent operations for metastases in the lung and mediastinum three times, when the serum AFP level remained remarkably high despite of intensive chemotherapy, and has been disease-free for three years after the last treatment. Our experience illustrates that the salvage surgery even under high serum marker levels may provide a beneficial outcome for selected cases of chemotherapy-resistant germ cell tumors.

Adult↗

PubMed2002

[Retroperitoneoscopic hand-assisted nephrectomy for live donor: Akita University experience].

PURPOSE: Laparoscopic nephrectomy is being employed in renal transplantation because of its minimal invasiveness, and several modifications in surgical procedures have been proposed. We devised a new technique of retroperitoneoscopic hand-assisted nephrectomy (RHAN) for live donor. We report the early experiences with this technique in 5 cases of live renal graft donor. TECHNIQUES AND SUBJECTS: The donors are placed in a modified decubitus position under general anesthesia, and all the laparoscopic surgical procedures were performed retroperitoneally using 3 port sites and a sealing device (LAP DISC) under a pressure of 10 mmHg. The LAP DISC is placed through a para-rectus abdominal skin incision of approximately 8 cm in length into the retroperitoneal cavity and used as a rout for instrumental as well as hand-assisted manipulations during the surgery. The hand-assistance through the LAP DISC made the surgical manipulation considerably easier and allowed the immediate removal of the graft after the interruption of the renal blood flow. This procedure was applied to 5 subjects, 4 in the left and one in the right kidney. RESULTS: The operating data were 264-359 min for operating time, 0.9-3.9 min for warm ischemic time and 40-755 ml for intra-operative blood loss, respectively. The serum creatinine level of the recipients at day 7 was 0.9-2.7 mg/dl. These values, except for operating time, were at the same range as those of the open live donor nephrectomy in our clinic. The 5 donors discharged 7-9 days after RHAN without any surgical complications. CONCLUSION: Our technique of RHAN will be a minimal invasive one in terms of both for the donors and the grafts, and be widely acceptable for donor nephrectomy on either side.

Female↗