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Sadao Kamidono

Publications and source records attributed to Sadao Kamidono.

124 records · Page 7Linked to original sources

Inhibition of urinary bladder motility by a spinal action of U-50488H in rats.

We examined the effect of a kappa agonist, U-50488H, upon the bladder motility of anaesthetized rats. The frequency of distension-induced rhythmic bladder contractions was reduced by the intravenous (10 mg kg(-1)) or intrathecal (10-100 microg) administration of U-50488H. The effect of intravenous U-50488H was inhibited by pre-treatment with nor-binaltorphimine (10 mg kg(-1), s.c.). The inhibition of bladder contractions by intrathecal U-50488H (30 microg) was eliminated with the concomitant use of nor-binaltorphimine (10 mg kg(-1), s.c.), and diminished by reserpine (4 mg kg(-1), i.p.), yohimbine (10 microg, i.t.) or methysergide (20 microg, i.t.). The amplitude of bladder contractions induced by an electrical stimulation of the pontine micturition centre was not inhibited by intrathecal U-50488H (30 and 100 microg). These results suggested that a kappa agonist could inhibit micturition reflex as well as other opioids, and at least part of the inhibition was due to the diminishment of bladder sensation based on the activation of the descending monoaminergic systems through the spinal kappa-opioid receptors.

3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cycloh↗

Automated sperm concentration analysis with a new flow cytometry-based device, S-FCM.

The S-FCM uses flow cytometry technology to measure sperm concentrations. Semen samples from 104 men attending a male infertility clinic were used to evaluate the reproducibility of results and the carryover rate with the S-FCM by performing between- and within-run imprecision analyses. In addition, sperm concentrations measured with the S-FCM were compared with those obtained by manual analyses with the Makler chamber and the improved Neubauer hemacytometer. The results showed that automated analyses with the S-FCM were highly reproducible and the carryover rate was 0.17% or less. In within-run imprecision assays, the coefficients of variation for the S-FCM were less than 5% at all sperm concentrations, while those for the Makler chamber were between 17.7% and 28.7% at lower sperm concentrations. The overall correlation between values measured with the S-FCM and those measured with the Makler chamber and improved Neubauer hemacytometer was excellent, but at lower sperm concentrations the correlation was lower. The S-FCM performed sperm concentration analyses in 110 seconds compared with 5 minutes for the Makler chamber and 10 minutes for the improved Neubauer hemacytometer. The S-FCM is suitable for quantitative measurement of lower sperm concentrations.

Autoanalysis↗

Over expression of CD44V8-10 in urinary exfoliated cells as an independent prognostic predictor in patients with urothelial cancer.

PURPOSE: CD44 is a widely expressed cell surface adhesion molecule, of which various isoforms arise from alternative RNA splicing mechanisms. Over expression of specific CD44 splice variants, namely CD44v8-10, is evident in various malignant tumors and is considered to be associated with disease progression. In this study, we investigated whether the transcriptional level of CD44v8-10 relative to that of the standard CD44 isoform would predict the extent and prognosis of urothelial cancer. MATERIALS AND METHODS: The CD44v8-10- to -standard CD44 ratio was measured in the tissue (40 urothelial cancer specimens and corresponding normal urinary tissue) and spontaneously voided urine samples of 150 patients with urothelial cancer and 50 with benign urological disease by reverse transcriptase-polymerase chain reaction using the set of primers capable of amplifying all CD44 splice variant isoforms. RESULTS: Initially any CD44 variant isoforms were barely detectable in normal urinary tissues, whereas CD44v8-10 was predominantly expressed in most urothelial cancer specimens. Furthermore, the CD44v8-10- to -standard CD44 ratio in urothelial cancer was closely associated with tumor progression. We then compared the ratio in urothelial cancer tissue and urinary exfoliated cells, and noted a linear and significant correlation of these 2 values in the same patients. Therefore, we investigated whether the CD44v8-10- to -standard CD44 ratio in urinary exfoliated cells would predict the prognosis and disease progression. The mean ratio in the urinary exfoliated cells of patients with invasive urothelial cancer was significantly higher than in those with superficial urothelial cancer. Of the patients with superficial bladder cancer disease-free survival rate of those with an elevated versus a normal ratio was significantly lower. Moreover, of the patients with advanced urothelial carcinoma who underwent complete resection disease-free survival of those with an elevated CD44v8-10- to -standard CD44 ratio was significantly lower than that of patients with a normal ratio. CONCLUSIONS: These results indicate that CD44v8-10 is strongly expressed in tumor tissue and evident at high levels in urinary exfoliated cells of patients with invasive versus superficial urothelial cancer. An elevated CD44v8-10- to -standard CD44 ratio in urinary exfoliated cells may serve as a novel prognostic predictor and indicator of disease extent in patients with urothelial cancer.

Alternative Splicing↗

Detection of beta-human chorionic gonadotropin expressing cells by nested reverse transcriptase-polymerase chain reaction in the peripheral blood stem cells of patients with advanced germ cell tumor.

PURPOSE: We investigated whether peripheral blood stem cells (PBSCs) were contaminated by tumor cells. MATERIALS AND METHODS: A total of 13 patients with advanced testicular cancer underwent PBSC transplantation at our institute. Nested reverse transcriptase-polymerase chain reaction using primers specific for beta-human chorionic gonadotropin (beta-HCG) or alpha-fetoprotein (AFP) detected 1 beta-HCG or AFP producing cell in 1 x 10(6) PBSCs. RESULTS: Although AFP messenger (m) RNA was not identified in any of the 13 patients, beta-HCG mRNA was detected in 7. All patients with beta-HCG mRNA in PBSCs had elevated serum beta-HCG before treatment. Three patients with a normal beta-HCG range before treatment did not have beta-HCG mRNA in the PBSCs. The serum beta-HCG level in the patients whose PBSCs were contaminated with tumor cells was significantly higher than in patients whose PBSCs contained no tumor cells. Four of the 7 patients with beta-HCG mRNA in PBSCs eventually died of cancer, whereas those whose PBSCs were not contaminated with tumor cells survived without disease. CONCLUSIONS: Patients with elevated serum beta-HCG levels are likely to have PBSCs contaminated by tumor cells. Moreover, the prognosis of patients with tumor cells in the PBSCs is poor.

Adolescent↗

Introducing the clusterin gene into human renal cell carcinoma cells enhances their metastatic potential.

PURPOSE: We recently reported a protective role of clusterin expression against apoptosis induced by a wide variety of stimuli in several human cancer models. In the current study we tested the hypothesis that clusterin over expression confers a benefit for the metastasis of renal cell carcinoma through the inhibition of apoptosis induced by the various obstacles the cancer cells may confront after detachment from their primary origin. MATERIALS AND METHODS: We introduced clusterin complementary DNA into human renal cell carcinoma ACHN cells, which do not express detectable level of clusterin expression, and generated the clusterin over expressing cell line ACHN/CL and the control vector only transfected cell line ACHN/C. In vitro anti-cell death activity under anchorage independent conditions among ACHN sublines was examined by limiting dilution assay and cell survival assay in suspension. To investigate the in vivo effects of clusterin over expression on metastatic potentials each cell line was injected into the tail vein or renal subcapsule of nonobese diabetic, severe combined immunodeficient mice and the metastatic features in all abdominal and thoracic organs were evaluated. RESULTS: ACHN/CL showed significantly enhanced growth in limiting dilution cultures compared with ACHN/C. The analysis of cell survival in the floating assay also revealed that ACHN/CL had a powerful survival advantage in suspension compared with ACHN/C. Furthermore, ACHN/CL formed more than 5-fold as many metastatic nodules in the lung after intravenous injection than ACHN/C. Similarly more marked lung metastasis was observed after implanting ACHN/CL cells into the renal subcapsule than after implanting ACHN/C cells. In contrast, there were no significant differences among ACHN sublines in the growth rates in vitro and in vivo, cell motility or invasive ability. CONCLUSIONS: These findings suggest that, if clusterin is over expressed, it prolongs cell survival under unfavorable conditions in the metastatic process, resulting in the enhanced metastatic potential of renal cell carcinoma.

Animals↗

Distribution of intracellular and extracellular expression of transforming growth factor-beta1 (TGF-beta1) in human testis and their association with spermatogenesis.

AIM: Spermatogenic dysfunction may result from thickening of seminiferous tubular basement membrane (BM) with tubular sclerosis. Transforming growth factor beta1 (TGF-beta1) plays an important role in fibrogenesis. The intracellular and extracellular expression of TGF-beta1 in the testis were immunohistochemically determined, using LC antibody (LC) for intracellular TGF-beta1 and CC antibody (CC) for extracellular TGF-beta1. METHODS: Twenty-three testicular biopsy specimens were obtained from varicocele and five from Sertoli-cell-only (SCO) patients, and five from normal volunteers. The relative area involved by the expression of TGF-beta1 for CC or LC (TGF-beta1 index for CC or LC) was examined, and semen parameters and serum hormonal levels and TGF-beta1 were analyzed. The Johnson score (JS), the BM thickness, and the tubular diameter were also determined. RESULTS: Immunoreactivity for CC was hardly detected. That for LC was detected in the Sertoli and germ cells. The TGF-beta1 index for LC was significantly higher in the varicoceles than in the normal testes. Interestingly, that for LC was significantly higher in the varicoceles than in the SCO. The level of serum TGF-beta1 was significantly higher in varicoceles than in the normal testes. CONCLUSION: The distribution of the intracellular and extracellular expression of TGF-beta1 in human testis was demonstrated. It suggests that TGF-beta1 is related to fibrosis of seminiferous tubules and may lead to spermatogenic disruption.

Adult↗

[Gene therapy for prostate cancer].

The substantial advances made in recent years in the molecular biology of malignant urological tumors and the associated progressive analysis of these conditions at a molecular level have spurred research aimed at gene-based treatment. In the field of prostate cancer, while there have been many ground-breaking studies particularly in the United States, none has yet led to a revolutionary treatment for recurrent prostate cancer. Gene-based treatment is being applied seriously in clinical settings, especially in the United States, but so far without significant effect. Many researchers worldwide are devoting energy to the development of effective vectors. By adjusting the promoter, which has the function of directing the vector, we have developed organ-specific vectors for the treatment of prostate cancer. In the present study, which targeted prostate cancer with bone metastasis, we developed a suicide-gene therapy using an adenovirus vector with an organ-specific osteocalcin promoter. Clinical trials of this vector have already been conducted at the University of Virginia in the United States and have so far confirmed the safety of the therapy. In the present paper we present the results of this gene-therapy research from the basic to the clinical phase alongside an outline of related research at our institution. Gene therapy for cancer is now being targeted not only against the primary tumor but systemic cancers including distant metastases; systemic administration of adenovirus vectors with organ-specific promoters may become one of the most promising systemic anti-tumor therapies of the next-generation.

Genetic Therapy↗

[A questionnaire survey on the theory of postoperative infection prophylaxis in urology].

A questionnaire survey on the theory of postoperative infection prophylaxis was conducted to obtain the consensus on perioperative antimicrobial use among urologists in Japan in the period from April to July 2000. Sixty-three of the 87 urologists replied, and the following consensus was obtained. An antimicrobial prophylaxis (AMP) agent should be chosen based on their efficacy against the pathogens expected to be contaminants, such as Escherichia coli, Staphylococcus spp., Klebsiella pneumoniae and Bacteroides fragilis group. Use an AMP agent that achieves a bactericidal concentrations in both the serum and operating site. Use an AMP agent that has little unfavourable side effects. The newer agents should be considered as a therapeutics for postoperative infections. The therapeutic antimicrobial agents having no cross-resistance to the AMP agents should be used, if postoperative infection is suspected or developed. The most commonly used agent for clean operations are cefazolin (CEZ), followed by cefotiam (CTM) and piperacillin (PIPC), in this order. For clean-contaminated operations, the most commonly used agent is CTM, followed by PIPC and CEZ.

Anti-Bacterial Agents↗

Clinical trial of in-situ hybridization method for the rapid diagnosis of sepsis.

We evaluated the utility of in-situ hybridization (ISH) for the rapid diagnosis of sepsis. We applied this approach to polymorphonuclear neutrophil (PMN)-rich smears from patients with suspected bacterial infection. Positive results by ISH were obtained in the smears of 123 of 292 patients (42%), while only 32 of the 292 (11%) were positive by blood culture. These findings indicate that ISH is almost four times more sensitive than the culture method for the detection of sepsis. ISH results are obtained within 1 day, while 1 day to 2 weeks is required for the results of blood culture. Blood culture and ISH methods detected the same bacteria in two patients. ISH also successfully identified the same bacteria in blood and PMN-rich body fluid (bronchoalveolar lavage samples) in 6 patients. In 19 patients, ISH of blood detected the same bacteria as those found in subcultures from other sources (e.g., stool, sputum, nasal cavity). We discuss these results in comparison with blood culture results in terms of evaluating a rapid approach to the management of patients with sepsis.

Journal Article↗

Expression and regulation of gp130 messenger ribonucleic acid in cultured immature rat Sertoli cells.

The expression of glycoprotein 130 (gp130) was studied in rat primary Sertoli cells by Northern blot analysis. Gp130 mRNA of 9.0 and 7.5 kb were detected in a variety of rat tissues including the testis. Gp130 mRNAs were detected in isolated, immature Sertoli cells. The levels of gp130 were significantly stimulated by the addition of interleukin-1-beta (IL-1-beta) or interleukin-6 (IL-6) but not by the addition of follicle-stimulating hormone (FSH). IL-6 activates intracellular signaling by binding with a receptor consisting of an 80-kDa ligand-binding protein, IL-6 receptor (IL-6R), and a second 130-kDa protein, gp130. As previously reported, expression of IL-6R mRNA in rat Sertoli cells was stimulated not only by IL-1-beta and IL-6 but also by FSH. In contrast, gp130 mRNA expression was not stimulated by FSH in our analysis. These data suggest that gp130 expression may be regulated by more than 1 mechanism and that production of gp130 and IL-6R, the 2 components of the IL-6 receptor system, may be regulated, at least in part, by a different pathway.

Animals↗

Serum cathepsin D and its density in men with prostate cancer as new predictors of disease progression.

We examined whether serum levels of cathepsin D (CatD) and its density (CatD-D), which was determined by dividing the serum levels of CatD by the prostate volume, could be used as predictors of the progression and prognosis in patients with prostate cancer. Serum levels of CatD in 40 healthy controls, 70 patients with benign prostatic hypertrophy (BPH) and 80 patients with prostate cancer were measured by a sandwich enzyme immunoassay, and prostate volume was measured using transrectal ultrasonography. The mean levels of CatD and CatD-D in patients with prostate cancer were significantly higher than those in healthy controls and patients with BPH. Furthermore, the CatD and CatD-D levels in prostate cancer patients with metastasis were significantly elevated compared with those in patients without metastasis. Among patients who underwent radical prostatectomy, the levels of CatD and CatD-D in patients with pathologically organ-confined disease were significantly lower than in those with extraprostatic disease. However, the elevated levels of CatD and CatD-D were not significantly associated with the cause-specific survival in prostate cancer patients. These findings suggest that the elevation of CatD or CatD-D could be used as new predictors of disease progression, but not prognosis, in patients with prostate cancer.

Aged↗

Resistance to cytotoxic chemotherapy-induced apoptosis in human prostate cancer cells is associated with intracellular clusterin expression.

We recently reported the powerful antiapoptotic activity of clusterin against various apoptotic stimuli in prostate cancer model systems; however, the precise mode of clusterin action in target cells remains largely unknown. In the present study, we therefore investigated whether intracellular or extracellular action of clusterin plays a crucial role in cytotoxic chemotherapy-induced apoptosis in androgen-independent human prostate cancer PC3 cells, which express a high level of clusterin. The sensitivity of PC3 cells to paclitaxel was increased by pretreatment with monoclonal antibody (mAb) to clusterin or antisense (AS) oligodeoxynucleotide (ODN) targeting the clusterin gene in a dose-dependent manner at up to 50 microg/ml or 1 microM, respectively. However, clusterin mAb failed to further enhance the sensitivity to paclitaxel of PC3 cells simultaneously treated with 1 microM AS clusterin ODN, whereas AS clusterin ODN further induced the apoptosis of cells treated with 50 microg/ml clusterin mAb. Moreover, the effects of clusterin mAb and AS clusterin ODN on PC3 cells were not reversed by additional treatment with exogenous recombinant clusterin protein. These findings suggest that the sensitivity of PC3 cells to paclitaxel-induced cytotoxicity may be regulated by the intracellular rather than extracellular level of clusterin.

Antibodies, Monoclonal↗

Predicting factors for collection of peripheral blood stem cells in patients with advanced germ cell tumors after cisplatin-based combination chemotherapy.

The objectives of this study were to identify the predictive factors for the mobilization of CD34 positive peripheral blood stem cells (PBSC) and to determine the optimal timing of PBSC harvest in patients with advanced germ cell tumors after cisplatin-based combination chemotherapy. Thirty-eight patients with advanced germ cell tumors were enrolled in this study. We undertook a retrospective analysis of 124 aphereses performed between March, 1994 and December, 1999. The predictive value for the optimal timing of PBSC harvest was determined by the analysis of the correlation factors between the number of harvested CD34 positive cells and several clinicopathological factors. The mean number of CD34 positive cells obtained at a single apheresis was 5.38 x 10(6)/kg, and the mean cumulative number of CD34 positive cells in each patient was 24.07 x 10(6)/kg. The number of CD34 positive cells were significantly correlated to the number of previously performed chemotherapies before PBSC harvest, leukocyte count and the percentage of immature leukocytes (myelocytes plus metamyelocytes) (p=0.0098, p=0.011, and p<0.0001, respectively). Multivariate analysis revealed that the number of chemotherapies and the percentage of immature leukocytes were independent predictors for the number of harvested CD34 positive cells (p=0.012 and p=0.016, respectively). The present findings suggest that PBSC harvest should be performed during first-line chemotherapy, and that the monitoring of the percentage of immature leukocytes could be a useful predictor for determining the optimal timing of PBSC harvest.

Adolescent↗

Long-term cryopreservation of peripheral blood stem cells in patients with advanced germ cell tumors using the dump-freezing method at -80 degrees C.

The objectives of this study were to evaluate the hematopoietic activity of peripheral blood stem cells (PBSCs) harvested from patients with advanced germ cell tumors after long-term cryopreservation in a mechanical freezer at -80 degrees C. Forty-one patients with advanced tumors were enrolled in this study. Flow cytometric analysis was performed to determine the total cell viability and the viability of CD34 positive cells of PBSCs stored between January 1995 and December 2001. The 41 patients were divided into two groups according to the duration of cryopreservation. In the 21 patients in whom the duration of storage was greater than 5 years, the total cell number did not change significantly before and after long-term cryopreservation (p=0.75). The percentage of viable cells and the total number of viable cells was significantly decreased after long-term cryopreservation (p<0.001 and p<0.05, respectively). However, the percentage of CD34 positive cells was significantly increased to 2.34% from 1.85% (p<0.05), resulting in non-statistically significant change in the total viable CD34 positive cells (p=0.98). A similar relation was found in the 20 patients whose storage duration was less than 2 years, although a significant change was found only in the percentage of viable cells. Moreover, pre-PBSCH factors, including age, cumulative dosage of cisplatin and the International Germ Cell Cancer Collaborative Group classification at the diagnosis did not affect the viable CD34 positive cell count after long-term cryopreservation. In conclusion, the present results suggest that CD34 positive cells could be successfully cryopreserved in a mechanical freezer at -80 degrees C for more than 5 years with no relation to pre-PBSCH factors and efficacy of PBSCH itself.

Adolescent↗

Recombinant interleukin-2 enhanced the antitumor effect of ADV/RSV-HSV-tk/ACV therapy in a murine bladder cancer model.

BACKGROUND: Previous studies demonstrated the antitumor effects of IL-2 and ADV/RSV-HSV-tk in bladder tumor models. In our study, we employed the intramuscular injection of recombinant IL-2 combined with ADV/RSV-HSV-tk gene therapy in the MBT-2 murine bladder tumor model. MATERIALS AND METHODS: In the in vitro study, after adenoviral gene transduction efficiency had been assessed, the cytotoxicity of ADV/RSV-HSV-tk/ACV was examined. In the in vivo study, ADV/RSV-HSV-tk was injected into MBT-2 subcutaneous tumors, ACV was injected intraperitoneally daily for 13 days and recombinant IL-2 was injected intramuscularly daily for 10 days. RESULTS: The X-gal staining of MBT-2 cells infected with 125 multiplicity of injection (MOI) indicated > 20% adenoviral gene transduction efficiency. The cell growth of MBT-2 infected with 125 MOI was significantly inhibited by 40 microM of ACV. In the in vivo study, the combination therapy significantly inhibited tumor growth in the MBT-2 tumor model. CONCLUSION: The systemic administration of recombinant IL-2 in combination with HSV-tk gene therapy exhibited an enhanced antitumor effect.

Acyclovir↗