Ascending contraction and descending relaxation in the distal colon of mice lacking interstitial cells of Cajal.

Recently an essential role of interstitial cells of Cajal (ICC) within myenteric plexus (ICC-MY) was suggested in ascending contraction and descending relaxation in the mouse ileum. The role of ICC in these neural reflexes was examined in the distal colonic segments prepared from the wild type and c-kit mutant, W/W(V) mice, in the present study. Localized distension of the segments from the wild type mice by using a small balloon resulted in ascending contraction and descending relaxation. In the segments from the mutant mice, localized distension also induced these neural reflexes similar to those observed in the wild type mice. Immunohistochemical examination demonstrated that ICC-MY and ICC present in muscle layers (ICC-IM) were severely disrupted in the mutant mouse, but only ICC, present within submucosal plexus (ICC-SMP), remained unchanged. In the small strips with ICC-SMP absent prepared from the mutant mouse, electrical field stimulation induced contraction or relaxation in the absence or presence of atropine, respectively. It was suggested that ICC have no important role in the ascending and descending neural reflexes in the mouse distal colon, this is in direct contrast to the role of ICC-MY in the ileum.     

The prognostic value of E-cadherin, α-, β- and γ-catenin in bladder cancer patients who underwent radical cystectomy

OBJECTIVES: To determine the value of the loss of expression of E-cadherin and cadherin associated molecules as useful markers for both prognosis and chemosensitivity in bladder cancer patients who have undergone radical cystectomy. PATIENTS AND METHODS: In 55 paraffin embedded specimens of radical cystectomy at our hospital from 1982 to 2000, the expression of E-cadherin, alpha-, beta- and gamma-catenin was examined by immunohistochemical staining. To evaluate the prognostic significance of these molecules, Kaplan-Meier survival curves were constructed and a statistical analysis was calculated by a log-rank test. A multivariate test (tumor stage, tumor grade, lymph node metastasis, configuration, the expression of E-cadherin, alpha-, beta- and gamma-catenin) was performed to detect prognostic markers. RESULTS: Normal expression was found in 33 cases (60.0%) for E-cadherin, 29 (52.7%) for alpha-catenin, 31 cases (56.4%) for beta-catenin, and 31 cases (56.4%) for gamma-catenin. The expression patterns for E-cadherin, alpha-, beta- and gamma-catenin were significantly correlated with each other (P < 0.01). Survival analysis showed a significant difference between normal and aberrant expression in each staining. A multivariate analysis revealed that the expression of alpha- catenin was an independent prognostic factor (P = 0.0191). In 23 patients that received adjuvant chemotherapy, there was a significant difference in survival between the normal and aberrant expression of alpha-catenin, but not other molecules. CONCLUSION: Alpha-catenin may not only be a good prognostic marker, but also one of key molecules that determine the chemosensitivities in patients with invasive bladder cancer.     

Chronic acid ingestion promotes renal stone formation in rats treated with vitamin D3

OBJECTIVE: Although hypercalciuria, a well-established adverse effect of vitamin D3, can be a risk factor of renal stone formation, the risk of nephrolithiasis has not been well defined. The consumption of a diet high in acid precursors is often cited as a risk factor for the development of calcium-based kidney stones. In the present study, we investigated the effect of chronic acid ingestion on kidney stone formation in rats treated with calcitriol (1-25[OH]2 D3). METHODS: Control rats (C-C), calcitriol-treated rats (C-V; three treatments of 0.5 microg of calcitriol per week) and acid-ingested (water containing 0.21 mol/L NH4Cl), calcitriol-treated (three treatments of 0.5 microg of calcitriol per week) rats (A-V) were fed in metabolic cages. After 1 month, urine, blood, kidney and bone samples were analyzed. RESULTS: The A-V rats exhibited elevated serum calcium concentrations, urinary calcium and phosphate excretion, urinary type I collagen cross-linked N-peptide (NTx)/creatinine values, mRNA expression of osteopontin in the kidney, and renal calcium contents as well as decreased bone mineral densities, compared with the C-C and C-V rats. Urinary citrate excretion was lower and NaDC-1 mRNA expression in the kidney was higher in the A-V rats than in the C-C and C-V rats. Calcium phosphate kidney stones were found in the A-V rats. CONCLUSIONS: The ingestion of NH4Cl, an acid precursor, promotes calcium phosphate kidney stone formation in calcitriol-treated rats. The chronic intake of a diet rich in acid precursors may be a risk factor for the development of kidney stones in subjects who are being treated with calcitriol.     

Chemo-endocrine therapy in patients with stage D2 prostate cancer

There have only been a few studies of chemo-endocrine therapy compared with endocrine therapy alone in newly diagnosed prostate cancer patients. We assessed the effects of these two therapies by comparing long-term survival rates. One hundred and twenty-nine patients were entered in this study between November 1977 and March 1992. Seventy-seven patients were treated with endocrine therapy alone. Other 52 patients received chemo-endocrine therapy, which included orchiectomy and/or diethylstilbestrol diphosphate (DES-DP) plus Cisplatin, with or without other cytotoxic agents. All patients had bone metastasis at the beginning of the study. There was a significant difference in survival between patients who received endocrine therapy and chemo-endocrine therapy (P = 0.0078). That is, survival rate was superior for the chemoendocrine therapy patients throughout the entire follow-up period. These data suggest that early chemo-endocrine therapy containing Cisplatin, with or without maintenance chemotherapy, is a potentially effective treatment for newly diagnosed metastatic prostate cancer and is worth further investigation via a randomized trial.     

The diagnosis and treatment of esophageal perforations resulting from nonmalignant causes

Esophageal perforations are extremely difficult to diagnose and treat. We report herein our results of a review of 26 patients with esophageal perforation which were spontaneous in 11, iatrogenic in 11, and caused by a foreign body in 4. Surgical treatment was performed in 7 of the patients with spontaneous rupture, but the remaining 19 patients were treated conservatively. The abnormality was found by plain radiography (X-ray) in 22 (85%) of the 26 patients, and by computed tomography (CT) in all 13 patients who underwent this procedure. The detection rates by esophagography and esophagoscopy were 100%, or all of 25 patients examined, and 60%, or 9 of 15 patients examined, respectively. Of 12 patients with underlying diseases, 4 (33%) died after the perforation, whereas only 1 (7%) of 14 patients without any underlying disease died. Postoperative empyema developed in all of 3 patients treated by intraoperative unfixed intrathoracic drainage (UID), but in none of the 4 treated by fixed intrathoracic drainage (FID). Conservative treatment achieved satisfactory results for spontaneous esophageal ruptures confined to the mediastinum, and for iatrogenic perforations and esophageal perforations caused by foreign bodies, provided there was no serious underlying disease such as advanced cirrhosis. Moreover, intraoperative FID proved useful in helping to prevent postoperative empyema.     

Clinicopathologic Study of Angiogenesis in Japanese Patients with Breast Cancer

p = 0.0007) and tumor necrosis (TN) (HMC: p = 0.0050). Univariate analysis showed that AMC or HMC was a statistically significant predictor of overall survival in all patients ( p = 0.0086 and p = 0.0307, respectively). Multivariate analysis showed that AMC was an independent predictor of node status when we fitted a model with node status, BVI, and either AMC or HMC; but HMC was not independent. However, when we fitted a model including all 11 of the other indicators and AMC or HMC, the node status, HG, and LI were independent predictors, but AMC and HMC were not. Although AMC was a better method than HMC for evaluating angiogenesis, we cannot confirm angiogenesis as a significant independent prognostic factor associated with long-term survival in Japanese breast cancer patients.     

EPIDEMIOLOGICAL CHARACTERISTICS OF PROSTATE CANCER IN GUNMA PREFECTURE, JAPAN

Background Prostate cancer is rare in Asia, but the number of patients is increasing in Japan. We conducted an epidemiological study of prostate cancer in Gunma Prefecture, Japan, to investigate the trends and characteristics of the disease.
Methods: The subjects were 1.411 prostate cancer patients newly diagnosed between 1985 and and 656 patients who died from prostate cancer between 1981 and 1992. The incidence and mortality rates were calculated by year, demographic region and age.
Results: The yearly incidence rate showed an increase but the mortality rate showed no marked fluctuations. There was no significant difference between urban and ruraI districts in either incidence or mortality rate. The incidence rate tended to be high in the northern part of the prefecture, but no marked variation in mortality rate was seen. The incidence and mortality rates in districts with a history of manganese mining were high compared to those in districts without mining. In contrast, the incidence and mortality rates in districts with a history of zinc mining were comparatively lower. Both incidence and mortality rates showed a marked increase with age. The age-specific incidence showed a double logarithmic relationship to age.
Conclusions: The increase of the yearly incidence rate might be due to changes in lifestyle and environmental factors, improved diagnostic techniques, and increased awareness among the general public regarding prostate disease. Further investigation is needed to clarify the pattern and the causes of regional differences in the incidence and mortality rates. The possibilities that manganese and zinc might be related to prostatic carcinogenesis are suggested. Int J Urol 1995:2:191–197     

Monovalent cation conductance of the sustained inward current in rabbit sinoatrial node cells

 Under the whole cell clamp, superfusion of the rabbit sinoatrial node cells with a Na⁺-free solution suppressed the sustained inward current (I_st), and the L-type Ca²⁺ current (I_Ca,L) could be recorded on depolarization less negative than –40 mV from the holding potential of –80 mV. On the other hand, replacement of Ca²⁺ with Mg²⁺ in the external solution suppressed inward-going I_Ca,L and isolated I_st. Under this condition, I_st measured as a nicardipine-sensitive current showed an activation threshold between –60 and –70 mV. The conductance sequence of I_st for monovalent ions was determined as Na⁺ > Li⁺ >> K⁺ @ Cs⁺ by replacing the external Na⁺ with these alkali metal ions. The contribution of I_st to the diastolic depolarization is discussed. Received: 12 June 1996 / Received after revision: 31 July 1996 / Accepted: 7 August 1996     

Pioglitazone improves the phenotype and molecular defects of a targeted Pkd1 mutant

Mutations of either PKD1 or PKD2 are associated with autosomal dominant polycystic kidney disease (ADPKD). The molecular function of the gene product of PKD1, polycystin-1, in vitro has been elucidated recently, but the molecular pathological consequences of the loss of polycystin-1 in vivo have remained unclear. We have generated a mouse with a targeted deletion of exons 2-6 of Pkd1 to study the molecular defects in Pkd1 mutants. Homozygote embryos (Pkd1(-/-)) developed hydrops, cardiac conotruncal defects and renal cystogenesis. Total protein levels of beta-catenin in heart and kidney and c-MYC in heart were decreased in Pkd1(-/-) embryos. In the kidneys of Pkd1(-/-), the expression of E-cadherin and PECAM in basolateral membranes of renal tubules was attenuated, and tyrosine phosphorylation of epidermal growth factor receptor and Gab1 were constitutively enhanced when cystogenesis started on embryonic day (E) 15.5-16.5. Maternally administered pioglitazone, a thiazolidinedione compound, resolved these molecular defects of Pkd1(-/-). Treatment with pioglitazone improved survival of Pkd1(-/-) embryos and ameliorated the cardiac defects and the degree of renal cystogenesis. Long-term treatment with pioglitazone improved the endothelial function of adult Pkd1(+/-). These data indicated that molecular defects observed in Pkd1(-/-) embryos contributed to the pathogenesis of ADPKD and that thiazolidinediones had a compensatory effect on the pathway affected by the loss of polycystin-1. Pathways activated by thiazolidinediones may provide new therapeutic targets in ADPKD.