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Osamu Nishizawa

Publications and source records attributed to Osamu Nishizawa.

At least 19 recordsLinked to original sources
PubMed2006

Bladder overactivity and hyperexcitability of bladder afferent neurons after intrathecal delivery of nerve growth factor in rats.

Nerve growth factor (NGF) has been proposed as an important mediator inducing bladder overactivity under pathological conditions such as spinal cord injury, bladder outlet obstruction, or cystitis. We therefore examined the effects of chronic NGF treatment on bladder activity and the properties of bladder afferent neurons. In adult female rats, NGF (2.5 microg/microl) was infused continuously into the intrathecal space at the L6-S1 level of spinal cord for 1 or 2 weeks using osmotic pumps (0.5 microl/h). Bladder afferent neurons were labeled with axonal transport of Fast Blue injected into the bladder wall. After intrathecal injection of NGF, cystometrograms under an awake condition showed bladder overactivity revealed by time-dependent reductions in intercontraction intervals and voided volume. ELISA analyses showed significant increases in NGF levels in L6-S1 dorsal root ganglia of NGF-treated rats. In patch-clamp recordings, dissociated bladder afferent neurons exhibiting tetrodotoxin (TTX)-resistant action potentials from NGF-treated animals were larger in diameter and had significantly lower thresholds for spike activation compared with sham rats. In addition, the number of TTX-resistant action potentials during 600 ms depolarizing pulses was significantly increased time dependently after 1 or 2 weeks of NGF application. The density of slowly inactivating A-type K+ currents was decreased by 52% in bladder afferent neurons with TTX-resistant spikes after 2 week NGF treatment. These results indicate that increased NGF levels in bladder afferent pathways and NGF-induced reduction in A-type K+ current density could contribute to the emergence of bladder overactivity as well as somal hypertrophy and hyperexcitability of bladder afferent neurons.

Animals↗
PubMed2006

Dopaminergic mechanisms controlling urethral function in rats.

AIMS: To investigate the role of dopamine receptor subtypes in the control of urethral activity. METHODS: Simultaneous recordings of intravesical and urethral perfusion pressure (UPP) were performed in rats under urethane anesthesia. Changes in coordinated activity of the bladder and urethral sphincter were examined following intravenous (i.v.), intrathecal (i.t.), or intracerebroventricular (i.c.v.) administration of dopamine D1- and D2-like receptor agonists (SKF38393 and quinpirole, respectively) and antagonists (SCH23390 and remoxipride, respectively). RESULTS: Quinpirole (0.03, 0.1, and 0.3 mg/kg i.v.) dose-dependently decreased baseline urethral pressure to 45.33 +/- 5.8, 33.7 +/- 3.3 (P < 0.05, n = 6), and 27.7 +/- 3.3 cm H(2)O (P < 0.05, n = 5) from the control value (46.0 +/- 4.0 cm H(2)O), respectively. i.c.v. injection of quinpirole (1 microg) decreased baseline urethral pressure to 33.6 +/- 5.0 cm H(2)O (P < 0.05, n = 4) from the control value (51.4 +/- 4.9 cm H(2)O) in contrast to the insignificant effects of i.t. administration of the drug (3 microg). The decrement of baseline pressure induced by quinpirole (0.1 mg/kg i.v.) was suppressed by alpha-bungarotoxin (BGT), a neuromuscular blocking agent. SCH23390 (1 and 3 mg/kg, i.v.) dose-dependently decreased the frequency of high frequency oscillation (HFO) of the urethral sphincter. SKF38393 or remoxipride did not have significant effects on any parameters of bladder and urethral activity. CONCLUSIONS: These results indicate that activation of D2-like dopamine receptors at a supraspinal site can suppress activity of the striated muscle urethral sphincter. Thus, decreased urethral resistance induced by D2 dopamine receptor activation might aggravate urge incontinence symptoms often seen in patients with Parkinson's disease (PD).

2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-ben↗
PubMed2006

Symptom assessment tool for overactive bladder syndrome--overactive bladder symptom score.

OBJECTIVES: Overactive bladder (OAB) is a common symptom syndrome with urgency, urinary frequency, and urgency incontinence. To collectively express OAB symptoms, we developed the overactive bladder symptom score (OABSS). METHODS: Four symptoms--daytime frequency, nighttime frequency, urgency, and urgency incontinence--were scored. The weighing score was based on a secondary analysis of an epidemiologic database. Psychometric properties were examined in five patient groups: OAB (n = 83), asymptomatic controls (n = 34), stress incontinence (n = 29), benign prostatic hyperplasia (n = 28), and other diseases with urinary symptoms (n = 26). RESULTS: The maximal score was defined as 2, 3, 5, and 5 for daytime frequency, nighttime frequency, urgency, and urgency incontinence, respectively. The sum score (OABSS 0 to 15) was significantly greater in the patients with OAB (8.36) than in the other patient groups (1.82 to 5.14). The distribution of the OABSS showed a clear separation between those with OAB and asymptomatic controls. The OABSS correlated positively with the individual scores (Spearman's r = 0.10 to 0.78) and quality-of-life scores assessed by the King's Health Questionnaire (Spearman's r = 0.20 to 0.49). The weighted kappa coefficients were 0.804 to 1.0 for each symptom score and 0.861 for OABSS. The posttreatment reduction in the OABSS was consistent with the global impression of patients of the therapeutic efficacy. CONCLUSIONS: The OABSS, the sum score of four symptoms (daytime frequency, nighttime frequency, urgency, and urgency incontinence), has been developed and validated. OABSS may be a useful tool for research and clinical practice.

Aged↗
PubMed2006

Improvement of polyuria, bladder sensation and bladder capacity following renal transplantation.

Here, we report a patient with renal failure and bladder dysfunction whose symptoms improved following renal transplantation. A 23-year-old woman underwent renal transplantation for renal failure as a result of dysplastic kidneys. Urodynamic evaluation prior to transplantation showed decreased bladder sensation and increased bladder capacity, probably because of congenital polyuria. One week after surgery, dry mouth disappeared, and urine volume normalized gradually. Urodynamic studies performed 3 and 10 months after transplantation showed improvement of bladder function, and the frequency/volume charts of urination also showed normalization of urine volume. Renal and bladder functions were almost normal 45 months after transplantation. Bladder dysfunction involves numerous factors, but the primary cause was probably congenital polyuria in the present case. This case suggested that blood purification and correction of urine volume by renal transplantation might lead to restoration of normal bladder function.

Adult↗
PubMed2006

Alveolar soft-part sarcoma of the retroperitoneum.

A 33-year-old woman was referred to Iida Municipal Hospital because of left back pain. Computed tomography showed a tumor (17 x 11 x 10 cm) in the left retroperitoneal space. T1- and T2-weighted magnetic resonance imaging showed an inhomogeneous mass with marginal blood vessels. The tumor was resected via lumbar oblique incision with the thoraco-abdominal approach. The tumor weighed 1800 g and consisted of nests of 5-100 large, loosely arranged, polygonal cells, surrounded by capillaries, resembling alveoli. The tumor cells were rich in cytoplasm, containing periodic acid-Schiff- and diastase-positive granules and typical crystals. The pathological diagnosis was alveolar soft-part sarcoma (ASPS). Alveolar soft-part sarcoma is a rare soft-tissue tumor that accounts for approximately 0.5-1% of soft-tissue sarcomas. Such tumors originating in the retroperitoneal space are extremely rare. Herein is reported a case of ASPS of the retroperitoneum with radiological and pathological findings.

Adult↗
PubMed2006

Effects of goshajinkigan (niu-che-sen-qi-wan) for resiniferatoxin-sensitive afferents on detrusor overactivity induced by acetic acid in conscious rats.

This study was performed to investigate the effects of goshajinkigan, a traditional Chinese herbal mixture, in conscious rats undergoing continuous cystometry. Systemic resiniferatoxin (RTX) pretreatment can block resiniferatoxin-sensitive (C-fiber) nerve-mediated bladder overactivity, such as that induced by intravesical administration of acetic acid. The effects of pretreatment with goshajinkigan and RTX alone or in combination on acetic acid-induced bladder overactivity in conscious rats were also compared. Female SD rats were divided into four groups. Groups 1 and 3 received normal food for 4 weeks, while groups 2 and 4 received goshajinkigan (0.09 g/kg/day) during the same period. Two days after bladder catheterization, groups 3 and 4 received RTX (0.3 mg/kg) injection, while groups 1 and 2 received vehicle alone. Cystometric investigations were performed on all animals 24 hours after RTX or vehicle injection. The effects of intravesical instillation of acetic acid (pH = 4.0) were compared with those of intravesical saline. Goshajinkigan significantly increased threshold pressure, voiding interval, micturition volume, and bladder capacity. Intravesical instillation of acetic acid induced bladder overactivity in both normal rats and in those pretreated with goshajinkigan. However, the effects of acetic acid on voiding interval and micturition volume were significantly different between rats given normal diet and those pretreated with goshajinkigan. The effect of acetic acid was not different between goshajinkigan- and RTX-pretreated rats. The results of the present study indicated that goshajinkigan increases voiding interval, micturition volume, and bladder capacity, and pretreatment with goshajinkigan partially blocks the bladder overactivity induced by intravesical administration of acetic acid in rats.

Acetic Acid↗
PubMed2006

[The serum concentration of interleukin-2 in a hemodialysis patient--report from interleukin adjuvant therapy for local recurrent renal cancer].

We started interleukin-2 (IL-2) adjuvant therapy after resection of a repeated local recurrence of renal cell carcinoma in a hemodialysis patient. It is reported that IL-2 is mainly metabolized in proximal tubules of the kidney. To determine the IL-2 concentration, we employed the ELISA method using anti-human IL-2 antibodies. At the concentration of 350,000 Japan reference unit (JRU) in a hemodialysis patient, the change in serum IL-2 was almost the same speed compared to 700,000 JRU in normal renal function patients, which was reported previously. This report may also be a good tool to define the ideal dose of IL-2 in hemodialysis patients.

Adjuvants, Pharmaceutic↗
PubMed2006

Annular rectal constriction due to infiltration by bladder cancer.

Invasive bladder cancers frequently show lymphatic or hematogenous metastasis. Furthermore, aggressive local invasion into adjacent structures is also commonly observed. However, the occurrence of rectal stricture due to infiltration by bladder cancer is relatively rare. Here, we report three patients with aggressive bladder cancer causing rectal obstruction.

Aged↗
PubMed2005

Recurrent retroperitoneal malignant nerve sheath tumor associated with neurofibromatosis type 1 responding to carboplatin and etoposide combined chemotherapy.

A 25-year-old man was referred to our hospital with left flank pain, and computed tomography (CT) and magnetic resonance imaging (MRI) revealed large retroperitoneal masses. Physical examination revealed many café-au-lait spots and superficial neurofibromas, and a diagnosis of neurofibromatosis type 1 (von Recklinghausen's disease) was made. The tumor was resected, and the pathological diagnosis was malignant peripheral nerve sheath tumor (MPNST). Six months after the operation, lung metastases were detected. Surgical resection was incomplete, as there were too many lesions. He received four courses of chemotherapy with carboplatin and etoposide, and the metastatic lung lesions were markedly decreased. After chemotherapy, complete resection of the remaining lung lesions was performed, and there has been no recurrence to date.

Adult↗
PubMed2005

Epstein-Barr virus-related primary central nervous system lymphoma after cadaveric renal transplantation improved by treatment with high-dose methotrexate followed by irradiation.

A 57-year-old man was admitted to hospital because of motor aphasia on 16 September 2000. He had an approximate 2-year history of haemodialysis treatment, since April 1997, and had received a cadaveric renal transplantation in July 1999. Computed tomography and magnetic resonance imaging (MRI) revealed a mass with ringed enhancement in the left temporal-parietal lobe. Primary central nervous system (CNS) lymphoma (diffuse large B cell type) was diagnosed based on an open brain tumour biopsy. Epstein-Barr virus early RNA (EBER) in situ hybridization showed positive signals in the nuclei of the CNS lymphoma cells. A dose reduction of immunosuppressant and three series of high-dose methotrexate (MTX) therapy with leucovorine rescue followed by irradiation (whole brain irradiation, 30 Gy; partial brain tumour irradiation, 20 Gy) were carried out for his primary CNS lymphoma. The patient is currently in good condition (September 2004) with no enlargement of the lymphoma, as examined by MRI every 3 months, and preserved renal function.

Aged↗
PubMed2005

Female para-urethral adenocarcinoma: histological and immunohistochemical study.

BACKGROUND: Female urethral cancer with a diverticular form is assumed to originate from the para-urethral duct, which is embryologically homologous to the male prostate gland. The purpose of the present paper was to investigate the female para-urethral adenocarcinomas histologically and immunohistochemically. METHODS: Surgical specimens obtained from six female patients with para-urethral adenocarcinomas were examined histologically, and an immunohistochemical study using antibodies against carcinoembryonic antigen (CEA), prostate specific antigen (PSA), and chromogranin A was performed. RESULTS: On histologic examination, the female para-urethral cancers were divided into five cases of mucin-producing-type adenocarcinoma and one case of clear cell-type adenocarcinoma. All five mucin-producing-type adenocarcinomas were positive with anti-CEA, and two of them showed neuroendicrine differentiation. One of them showed a focally positive area with anti-PSA. The clear cell-type adenocarcinoma had no positive reactions to these antibodies. CONCLUSIONS: On the basis of histologic structure, positive CEA staining, and the presence of focal neuroendocrine differentiation, mucin-producing-type adenocarcinomas may arise from the proximal part of the para-urethral duct.

Adenocarcinoma, Clear Cell↗
PubMed2005

Anatomical and histological studies of so-called Müllerian duct cyst.

BACKGROUND: We examined so-called Müllerian duct cysts both histologically and immunohistochemically with anatomical observation to investigate the etiology of the 'Müllerian duct cyst'. METHODS: Five cystic lesions located in the prostatic midline were obtained from surgical specimens. A communication between the cystic lesion and the urethra via the utricular orifice was looked for and the specimens were subjected to histological and immunohistochemical testing. RESULTS: A communication between the cyst and the urethra was confirmed in four cases, but not in one case. Histological and immunohistochemical examinations of the epithelium lining indicated that its characteristics were identical to those of the prostatic utricle in all cases. CONCLUSIONS: The so-called Müllerian duct cyst exhibits features comparable to those previously described in the prostatic utricle. There is no evidence that these cystic lesions originate from the Müllerian duct remnant, at least in the epithelial lining. We suggest that they should be termed a prostatic utricular cyst or cystic dilation of the prostatic utricle, depending on whether an outlet to the urethra is absent or present, respectively.

Aged↗
PubMed2005

Prostate-specific antigen, Gleason sum and clinical T stage for predicting the need for radionuclide bone scan for prostate cancer patients in Japan.

AIM: In the present study, we evaluated the relationships between prostate-specific antigen (PSA) level and bone metastasis, between Gleason sum and bone metastasis, and between clinical T stage and bone metastasis in Japanese patients. METHODS: Between November 1998 and June 2004, we performed ultrasound-guided biopsies on 709 patients (mean age: 70.5 years, range: 39-90). Prostate cancer was detected in 339 patients (47.8%), 297 (87.6%) of whom underwent a radionuclide bone scan. In close collaboration with orthopedists, bone computed tomography scans, bone magnetic resonance imaging and/or plain rentogenograms were performed for cases that were difficult to diagnose as bone metastasis through radionuclide bone scans only. RESULTS: We detected 61 (20.6%) bone metastasis cases in 296 patients. A simple linear regression analysis between log[PSA] and bone metastasis (n = 296) produced a significant relationship (P < 0.05). When we set the cut-off PSA value for the indication for a bone scan at 15 ng/mL, the possibility of bone metastasis was 10%. However, from our experience, there was no bone metastasis in the patients whose Gleason sums were less than five, and in the patients whose Gleason sum were five or more, and the PSA levels were less than 15, there was no bone metastasis. The rate of bone metastasis increased with the increase of PSA level. In the clinical T1-T2 stage cases, there were significant higher PSA levels in the cases with bone metastasis. In the T1-T2 patients whose PSA levels were less than 16, there was no bone metastasis. CONCLUSIONS: From the analysis of PSA, Gleason sum and clinical T stage, we suggest that bone scan is unnecessary for patients whose PSA level is less than 15 ng/mL or Gleason sum is less than five.

Adult↗
PubMed2005

Elimination of rat spinal neurons expressing neurokinin 1 receptors reduces bladder overactivity and spinal c-fos expression induced by bladder irritation.

Substance P (SP) binding to neurokinin 1 receptors (NK1R) in the spinal cord reportedly plays an important role in the micturition reflex as well as in nociceptive responses. We therefore investigated the effect of ablation of NK1R-expressing neurons in the spinal cord using saporin, a ribosome-inactivating protein, conjugated with [Sar9, Met (O2)11]SP, a specific ligand of NK1R (SSP-saporin), on the micturition reflex in rats. In female Sprague-Dawley rats, SSP-saporin (1.0 or 1.5 microM) or saporin (1.5 microM) only was injected through an intrathecal catheter implanted at the L6-S1 level of the spinal cord. Three weeks after intrathecal administration of SSP-saporin, NK1R immunoreactivity in lamina I of the spinal cord was significantly reduced, but cystometric parameters in awake rats were not altered. Instillation of capsaicin (15 microM) into the bladder of normal rats induced bladder overactivity. This response to capsaicin was significantly suppressed in SSP-saporin-treated animals. SSP-saporin treatment also decreased c-fos expression in the dorsal horn of the spinal cord induced by instillation of capsaicin into the bladder. These data indicate that NK1R-expressing neurons in the superficial layer of the dorsal horn play an important role in transmission of nociceptive afferent information from the bladder to induce bladder overactivity and spinal c-fos expression elicited by bladder irritation. Toxin-induced damage of NK1R-expressing neurons in the lumbosacral spinal cord may provide an effective modality for treating overactivity and/or nociceptive responses in the bladder without affecting normal micturition.

Animals↗
PubMed2005

Müllerian duct remnant involving Wolffian system: a case report and literature review.

A 14-month-old boy with repeated left acute epididymitis was admitted to our department. Ultrasonography detected a midline round cystic mass in a retrovesical region. This was easily opacified by cystourethrography and seen to have a free communication with the posterior urethra. Since urethroscopy revealed a passable orifice in the center of the verumontanum, while a cystic-wall biopsy specimen showed squamous epithelium, we considered this cystic lesion to be an enlarged prostatic utricle. Vasography showed that the bilateral vasa was implanted directly into this cystic lesion, and was the possible cause of his left epididymitis. Ligature of the left vas deferens was performed to prevent left epididymitis. An enlarged prostatic utricle involving the vasa is a rare presentation.

Cysts↗
PubMed2004

Loss of calponin h1 in renal angiomyolipoma correlates with aggressive clinical behavior.

OBJECTIVES: To investigate whether any immunohistochemical differences exist between two types of renal angiomyolipomas (AMLs). Renal AMLs are generally considered to be benign in nature. However, a few of these tumors have been reported to involve other organs. METHODS: Tissue specimens from 3 cases of clinically aggressive and 9 cases of clinically indolent renal AMLs were examined histologically and immunohistochemically using antibodies against calponin h1 and alpha-smooth muscle actin. Immunostaining was evaluated semiqualitatively as no staining to strong staining. RESULTS: The tumor cells in the myomatous component of the aggressive type did not show any reaction to the antibody to calponin h1 protein, but they showed strong immunoreactions with the antibody to the alpha-smooth muscle actin antigen. All cases of the nonaggressive AMLs demonstrated strong immunoreactions with both antibodies used. CONCLUSIONS: Our initial results in a small series of cases suggest a potential molecular difference between the aggressive and nonaggressive type of AMLs. Loss of calponin h1 from the tumor cells of the aggressive type might be related to their pathologically invasive features, and this aggressive type might be categorized into an intermediate type between the benign and malignant types.

Actins↗
PubMed2004

Radical cystectomy for invasive bladder cancer: results of multi-institutional pooled analysis.

BACKGROUND: We report the outcome of radical cystectomy for patients with invasive bladder cancer, who did not have regional lymph node or distant metastases, at 21 hospitals. METHODS: Retrospective, non-randomized, multi-institutional pooled data were analyzed to evaluate outcomes of patients who received radical cystectomy. Between 1991 and 1995, 518 patients with invasive bladder cancer were treated with radical cystectomy at 21 hospitals. Of these, 250 patients (48.3%) received some type of neoadjuvant and/or adjuvant therapy depending on the treatment policy of each hospital. RESULTS: The median follow-up period was 4.4 years, ranging from 0.1 to 11.4 years. The 5-year overall survival rate was 58% for all 518 patients. The 5-year overall survival rates for patients with clinical T2N0M0, T3N0M0 and T4N0M0 were 67%, 52% and 38%, respectively. The patients with pT1 or lower stage, pT2, pT3 and pT4 disease without lymph node metastasis had 5-year overall survivals of 81%, 74%, 47% and 38%, respectively. The patients who were node positive had the worst prognosis, with a 30% overall survival rate at 5 years. Neoadjuvant or adjuvant chemotherapy did not provide a significant survival advantage, although adjuvant chemotherapy improved the 5-year overall survival in patients with pathologically proven lymph node metastasis. CONCLUSIONS: The current retrospective study showed that radical cystectomy provided an overall survival equivalent to studies reported previously, but surgery alone had no more potential to prolong survival of patients with invasive cancer. Therefore, a large-scale randomized study on adjuvant treatment as well as development of new strategies will be needed to improve the outcome for patients with invasive bladder cancer.

Adult↗