Role of the transversus perinei profundus muscle on voiding: The meaning of UPmax in patients with paralyzed urethral sphincter

Urodynamic study of 66 patients with caudal injury and of 7 patients who underwent saddle block was evaluated by putting emphasis on the maximal pressure of the urethra (UPmax). The static pressure of 49.7 ± 10.8 cm H₂O in the membranous urethra of the patients with completely paralyzed sphincter raised the question that some active muscle that functions to open the membranous urethra must have been working during physiological urination. Urodynamic findings of detrusor sphincter relationship, monitored by pressure and electromyogram (EMG) measurement, suggested that the combined reflections of the pelvic floor muscle and urethral sphincter are present. We concluded that this would be induced by the transversus perinei profundus muscle contraction and the urodynamic interpretation would be re-integrated on the role of this muscle on active urethral opening mechanism. © 1996 Wiley-Liss, Inc.     

Exercise modulates postreceptor insulin signaling and glucose transport in muscle-specific insulin receptor knockout mice

Physical exercise promotes glucose uptake into skeletal muscle and makes the working muscles more sensitive to insulin. To understand the role of insulin receptor (IR) signaling in these responses, we studied the effects of exercise and insulin on skeletal muscle glucose metabolism and insulin signaling in mice lacking insulin receptors specifically in muscle. Muscle-specific insulin receptor knockout (MIRKO) mice had normal resting 2-deoxy-glucose (2DG) uptake in soleus muscles but had no significant response to insulin. Despite this, MIRKO mice displayed normal exercise-stimulated 2DG uptake and a normal synergistic activation of muscle 2DG uptake with the combination of exercise plus insulin. Glycogen content and glycogen synthase activity in resting muscle were normal in MIRKO mice, and exercise, but not insulin, increased glycogen synthase activity. Insulin, exercise, and the combination of exercise plus insulin did not increase IR tyrosine phosphorylation or phosphatidylinositol 3-kinase activity in MIRKO muscle. In contrast, insulin alone produced a small activation of Akt and glycogen synthase kinase-3 in MIRKO mice, and prior exercise markedly enhanced this insulin effect. In conclusion, normal expression of muscle insulin receptors is not needed for the exercise-mediated increase in glucose uptake and glycogen synthase activity in vivo. The synergistic activation of glucose transport with exercise plus insulin is retained in MIRKO mice, suggesting a phenomenon mediated by nonmuscle cells or by downstream signaling events.     

Evaluation of long-term sequential changes in bone mass and strength following withdrawal of incadronate disodium (YM175) in ovariectomized rats

We evaluated the long-term effects of withdrawal of a newer third-generation bisphosphonate, incadronate disodium (YM175), on both cancellous and cortical bone mass and strength in ovariectomized (OVX) rats. One hundred and sixty female SD rats at 13 weeks of age were randomized into four groups: sham-operated, OVX, and low- and high- YM (0.01 or 0.1 mg/kg s.c., three times a week after OVX). After 4 weeks of treatment with vehicle or incadronate disodium, rats from each group (n = 8) were killed at 0 (baseline), 3, 6, 9, and 12 months after the withdrawal of YM175. Histomorphometric studies of the proximal tibia revealed a dose-dependent decrease in OVX-induced bone turnover; cancellous bone volume was significantly higher in the YM groups compared with the OVX control group up to 6 months after withdrawal at low dose and up to 12 months after withdrawal at high dose. The low-dose group showed little effect on tibial diaphyseal cortical bone volume and width, while the high-dose group preserved both cortical parameters 12 months after withdrawal. Mechanical testing of femurs revealed that both metaphyseal and diaphyseal strengths were significantly higher at high dose compared with the OVX group until 12 months after withdrawal. These observations demonstrated that high-dose incadronate disodium preserved both cancellous and cortical bone mass and strength in OVX rats for 12 months after withdrawal of the agent. Received: July 7, 2000 / Accepted: October 3, 2000     

Changes in serotonin dynamics in the gastrointestinal tract of Colon-26 tumour-bearing mice: effects of cisplatin treatment

Severe nausea and vomiting are common side effects of anti-cancer chemotherapy. 5-HT3 receptor antagonists have been used for the treatment of these gastrointestinal symptoms. The purpose of this study was to examine whether specific changes in serotonin dynamics occurred in the gastrointestinal tract in mice in which Colon-26 adenocarcinoma cells were injected s.c., especially after treatment with cisplatin. The serotonin content of the small intestine of mice inoculated s.c. with Colon-26 adenocarcinoma increased significantly 2 weeks after the inoculation of the tumor cells; this was associated with an increase in tryptophan hydroxylase activity and the number of enterochromaffin cells as compared with control mice. Intravenous injection of cisplatin significantly reduced the serotonin content in the small intestine of Colon-26 tumour-bearing mice but not in control mice. The spontaneous release of serotonin from isolated intestine was not different between Colon-26 tumour-bearing and control mice; however, pretreatment of mice with cisplatin induced two fold increases in serotonin release from duodenum, jejunum and ileum in Colon-26 tumour-bearing mice but not in control mice. These results indicate that a region-specific increase in the number of enterochromaffin cells is observed in the intestine of Colon-26 tumour-bearing mice, associated with an increase in the serotonin content and tryptophan hydroxylase activity. Cisplatin treatment induced the release of serotonin from affected enterochromaffin cells in the gastrointestinal tract, which may be related to the occurrence of nausea in clinical use.     

Keratoacanthoma with Glandular Proliferation

A case of keratoacanthoma (KA) with glandular proliferation was reported. The tumor was a firm, dome-shaped, elevated nodule on the cheek of an 82-year-old Japanese male. Generally, the tumor showed the typical histopathological features of KA; slight nuclear atypia and mitotic figures were present in a cup-shaped proliferation of keratinocytes and, in the center of the lesion, a keratin-filled crater with nests of dyskeratotic and acantholytic cells was seen. In the bottom of the lesion, a glandular structure forming branching, thin lumina was observed. The epithelium of the lumina was made up of two or more layers of columnar or cuboidal cells without keratinization. Tall columnar cells with oval nuclei were located in the luminal row and small cuboidal cells with round nuclei and scanty cytoplasm were in the outer layer. Immunohistochemical staining revealed that only the glandular structure was carcinoembryonic antigen positive. Lectin binding patterns observed in the glandular proliferation were similar to those reported for the apocrine gland. KA sometimes exhibits an adenoid structure in its lesion because of acantholytic changes. However, KA associated with true glandular proliferation has not been reported as far as we know, and our case is the first reported one. KA is thought to be a tumor of follicular origin, and the glandular proliferation observed in the present case seemed to have certain characteristics that suggest its apocrine origin.     

Peripancreatic Fluid Cytology: Detection of Early Rejection versus Graft Pancreatitis after Canine Pancreatic Transplantation

n = 25) or autograft ( n = 37) heterotopically in the neck. This study included five groups: allografts without immunosuppression (group A, n = 12), allografts with immunosuppression (group B, n = 13), autografts without immunosuppression (group C, n = 11), autografts with immunosuppression (group D, n = 12), and autografts treated by 45 minutes of pretransplant warm ischemia to induce acute graft pancreatitis (group E, n = 14). A closed suction drainage catheter was placed next to the graft to collect peripancreatic fluid daily after the transplant. PFC was performed using May-Gruenwald-Giemsa double-staining technique and compared to the corresponding histology through the observation period. In analyses of 50 functioning grafts, PFC performed on day 1 showed similar neutrophil accumulations in all groups. In sharp contrast, on days 3 and 6, group A had dramatically increased mononuclear cell concentrations in PFC, whereas groups B, C, and D showed significantly lower concentrations, the percent of mononuclear cells among total leukocytes being 47.3 ± 23.4%, 11.8 ± 4.9%, 4.3 ± 1.8%, and 6.4 ± 2.4% (day 3); and 32.7 ± 9.8%, 10.5 ± 4.8%, 7.2 ± 4.2%, and 8.6 ± 6.4% (day 6) in groups A, B, C, and D, respectively. On the other hand, in group E numerous degenerating neutrophils with a marked to moderate increase in necrotic tissue fragments were observed by PFC on days 3 and 6. In terms of graft histology on days 3 and 6, group A showed interstitial mononuclear cell infiltration indicating an acute rejection process, whereas groups B, C, and D had minimal inflammatory cell infiltration. In group E graft pancreatitis was histologically confirmed on days 3 and 6. These results suggest that PFC after pancreas transplantation could be a safe, simple, useful diagnostic tool for discriminating early graft rejection from graft pancreatitis.