Effects of various drugs on bladder function in conscious restrained-denervated rats placed in a restraining cage and produced by transection of the hypogastric nerve

We evaluated the effects of various intravenously administered drugs, which had been shown to influence bladder function in anesthetized and/or conscious rats, on the cystometrogram in conscious restrained-denervated rats (produced by transection of the hypogastric nerve) placed in a restraining cage in comparison to those in conscious restrained-intact rats (with the hypogastric nerve intact) placed in a restraining cage. The bladder capacity in the restrained-denervated rats was smaller than that in restrained-intact rats and did not change when they were transferred to a wide cage, but the bladder capacity of the restrained-intact rats decreased following transfer to the wide cage. Therefore, the activity of the hypogastric nerve in conscious rats appears to be stimulated by restraint. Atropine suppressed the amplitude of the micturition contraction (time to micturition in the cystometrogram). In the restrained-denervated rats, thiopental and indomethacin increased the bladder capacity at almost the same doses as those in restrained-intact rats, but it took a higher dose of morphine to increase the bladder capacity than in restrained-intact rats. These findings suggest that cystometrography in restrained-denervated rats is a useful method for evaluating the effect of a newly developed agent on bladder function without any influence from the hypogastric nerve.     

Statistical evaluation of determinants of progression of superficial bladder cancer by proportional hazards model

To evaluate clinical and pathological factors present at the initial consultation which affect disease progression, we reviewed data from 223 patients with superficial bladder cancer (pTa and pT1) who were initially treated at Nagoya University Hospital between January 1973 and December 1987. The factors included in the present analysis were age, sex, symptoms, interval between initial symptoms and first consultation, location of tumor, size, number, endoscopic shape, histological pattern of growth, grade and stage. The median duration of the follow-up after initial treatment was 46 months. Of the 223 patients, 17 died: 8 (3.6%) of bladder cancer and the remaining 9 (4.0%) of unrelated causes. Disease progression developed in 12 patients (5.4%): muscle invasion of the bladder wall in 11 and lung metastasis in one. The interval between initial treatment and progression ranged from 4 to 108 months, with a median of 11.5 months. Of the 12 patients, 9 (75%) had disease progression within 2 years. Progression was significantly associated with poor prognosis (p less than 0.001): the 5-year actuarial survival rates were 47.1% and 92.8% in patients with and without progression, respectively. Univariate analysis by Cox's proportional hazards model demonstrated that characteristics such as irritative bladder symptoms, higher-grade tumors, invasion into lamina propria, and nonpapillary growth seen at initial consultation were significantly related to disease progression. Cox's proportional hazards model produced hazard ratios of 10.2 in irritative bladder symptoms (yes vs. no), 6.3 in histological grade (grade 3 vs. grades 0-2), 4.9 in stage (pT1 vs. pTa), and 4.7 in pattern of growth (papillary vs. nonpapillary).(ABSTRACT TRUNCATED AT 250 WORDS)     

Design of a Centrifugal Blood Pump with Magnetic Suspension

Abstract: A new concept blood pump, whose impeller is suspended by permanent magnets and a mechanical pivot without seals or ball bearings, is presented in this paper. The primary aim of the blood pump is an application to implantable artificial hearts. The prototype model is of a centrifugal type with a four-vaned semiopen impeller 50 mm in diameter. Since this mechanism has no seals or ball bearings, flow stagnation or heat generation that might cause blood cell denaturation is expected to be small. The results of performance testing for the prototype model 2 were satisfactory regarding pump head and efficiency. The radial-suspension magnets and the magnetic coupling were stable. As a result, the present mechanism has been verified to be a candidate applicable to implantable artificial hearts.     

Surgical results of performing R4 gastrectomy for gastric cancer located in the upper third of the stomach

Because gastric cancers located in the upper third of the stomach are difficult to detect at an early stage, the surgical results remain poor. We performed R4 gastrectomy as a radical procedure for 25 patients, involving complete resection of the latero-aortic and interaorticovenous lymph modes above and below the left renal vein, in combination with the ordinary R2 or R3 gastrectomy (the R4 group). These patients were compared with 156 others who underwent R2 gastrectomy alone (the R2 group). There were no significant differences in operation time, blood loss, or the incidence of complications between the two groups; however, when the survival rates of the patients with tumors invading beyond the subserosa were compared, the 5-year survival rate was found to be significantly higher in the R4 group than in the R2 group. Furthermore, in patients with para-aortic nodal involvement, a significant survival advantage was observed in the R4 group, as compared with the R2 group. These results suggest that the R4 gastrectomy is a rational approach for patients with advanced gastric cancer located in the upper third of the stomach.     

The role of magnetic resonance cholangiopancreatography (MRCP) after resection of the pancreas

Magnetic resonance cholangiopancreatography (MRCP) was performed in 35 patients to evaluate the feasibility of its use as a postsurgical imaging technique after resection of the pancreas. The surgical procedures performed were: pancreatoduodenectomy in 22 patients, segmental pancreatectomy in 1, distal pancreatectomy in 7, and pyroluspreserving pancreatoduodenectomy in 5. The pancreatic duct was shown in its entirety in 24 of the 35 patients (68.6%) and was partially visualized in 8 patients (22.9%), but the intrahepatic and extrahepatic bile ducts were visualized completely in all patients. Furthermore, MRCP was able to demonstrate lesions in 3 of 6 patients who had shown clinical evidence of recurrence. The visualization of the pancreatic and bile duct system was satisfactory despite anatomical changes brought about by resection of the pancreas. Thus, we conclude that MRCP is an appropriate follow-up screening test for patients with suspected abnormalities of the biliary and pancreatic duct system.     

Pharyngeal Patency in Response to Advancement of the Mandible in Obese Anesthetized Persons

Background: During anesthesia in humans, anterior displacement of the mandible is often helpful to relieve airway obstruction. However, it appears to be less useful in obese patients. The authors tested the possibility that obesity limits the effectiveness of the maneuver.

Methods: Total muscle paralysis was induced under general anesthesia in a group of obese persons (n = 9; body mass index, 32 +/- 3 kg sup -2) and in a group of nonobese persons (n = 9; body mas index, 21 +/- 2 kg sup -2). Nocturnal oximetry confirmed that none of them had sleep-disordered breathing. The cross-sectional area of the pharynx was measured endoscopically at different static airway pressures. A static pressure-area plot allowed assessment of the mechanical properties of the pharynx. The influence of mandibular advancement on airway patency was assessed by comparing the static pressure-area relation with and without the maneuver in obese and nonobese persons.

Results: Mandibular advancement increased the retroglossal area at a given pharyngeal pressure, and mandibular advancement increased the retropalatal area in nonobese but not in obese persons at a given pharyngeal pressure.     

Temporal and spatial expression of transforming growth factor-β in the healing patellar ligament of the rat

We investigated the temporal and spatial expression of transforming growth factor-β in the healing patellar ligament of the rat by immunohistochemistry. The mid-portion of the medial half of the patellar ligament in 14-week-old male Wistar rats was cut transversely with a scalpel. On day 1 after ligament injury, diffuse staining for transforming growth factor-β was observed in the extracellular matrix filling the wound, and the staining in the adjacent ligament tissue was as weak as it was in the normal ligament. On day 3, the intensity of the diffuse extracellular staining decreased, and the staining was observed in correspondence with the cellular distribution in the wound site and in the adjacent uninjured ligament tissue. On day 7, the intense staining was widely distributed over the whole length of the ligament tissue. On day 28, the staining for transforming growth factor-β was still observed at the wound site and in the adjacent uninjured ligament tissue, where the staining was reduced in intensity but still stronger than it was in the normal ligament. On day 56, the expression of transforming growth factor-β was still detectable at the wound site: however, in the adjacent uninjured ligament tissue, it had almost subsided to the normal level. The results of the present study suggest that ligament healing may be accompanied by extensive changes in the expression of transforming growth factor-β over the whole length of ligament tissue.     

Maturation of Pulmonary Metastases of Wilms' Tumor after Therapy: A Case Report

A case is reported of Wilms' tumor associated with multiple pulmonary metastases histologically showing maturation of the tumor cells at 9 years after the resection of the primary tumor and intensive therapy. A huge tumor of a 22-month-old patient's right kidney was resected. The tumor was diagnosed as Wilms' tumor of mesenchymal type (stage 1), which consisted of predominantly immature mesenchymal tissue including rhabdomyoblasts, smooth muscle and fibrous tissue, and few blastemal and epithelial components. Intensive preoperative and postoperative chemotherapy with actinomycin D and vincristine and postoperative irradiation therapy totaling 16 Gy were carried out. The patient was regularly followed up uneventfully until 9 years after the surgery. On routine chest x ray at the age of 10 years 11 months, multiple pulmonary nodules were found. The excised nodules from the bilateral lungs disclosed similar histology, exclusively composed of dense collagen bundles and fibrocytes intermingled with mature striated muscle bundles. No immature tumor components were detected. The possible effect of intensive therapy in this maturation was stressed, although spontaneous benign differentiation of tumor cells cannot be excluded.