Basic study on velocity-flow urodynamics using Doppler sonography: Simultaneous detection of cavitation and Doppler signals in an artificial urethral model

BACKGROUND: We have developed velocity-flow urodynamics using Doppler sonography based on the hypothesis that microbubbles formed in the urethra are responsible for Doppler signals. In order to confirm this hypothesis derived from Bernoulli's principle, we investigated the simultaneous detection of cavitation noise and Doppler signals in an experimental system. METHODS: An experimental circuit was built in which a stenosis was created using a glass or silicon tube with tap water used as the sample fluid. Doppler signals, pressure before and after the stenosis, flow rate, flow velocity and cavitation noise were measured. Direct detection of cavitation with a high-speed charged-coupled device (CCD) camera was conducted in the glass tube. The relationship between cross-sectional area and flow velocity in terms of the detection of Doppler signals was analyzed in the silicon tube study. RESULTS: In the glass tube study, a high-speed CCD camera clearly detected masses of microbubbles associated with cavitation. The range of flow rates creating cavitation completely corresponded with those producing Doppler signals detected by ultrasonography. A similar correlation was observed in the silicon tube study, which showed that a low flow velocity of 41.5 cm/sec through a stenosis with a cross-sectional area of 20 mm(2) created Doppler signals at a flow rate of 8.3 mL/sec. CONCLUSION: The results of the present study confirmed that microbubbles created in flowing urine are responsible for Doppler signals. Measurement of velocity-flow urodynamics has great potential to become a non-invasive and reliable alternative to conventional pressure- flow urodynamic studies.     

伊文氏蓝染色对大鼠脑内肿瘤生物学标记方法的研究

目的研究在大鼠脑内肿瘤模型中生物学染色标记脑内肿瘤的方法。方法选择F344大鼠,移植体外培养的RG2胶质瘤细胞制作脑内肿瘤模型,移植18d后经大腿静脉注射伊文氏蓝(Evans blue,EB)染色肿瘤组织,探讨生物学染色对脑内肿瘤的标示作用和手术中对肿瘤和周围正常脑组织鉴别的意义。结果EB浓度在100mg/kg时,肿瘤组织染色成鲜明蓝色,同时大鼠的皮肤和所有器官都被染色成蓝色;当浓度低于10mg/kg时,仅染色肿瘤组织而皮肤和其他器官不被染色;肉眼可鉴别的最低静注浓度为1.25mg/kg。肿瘤组织的染色效果持续到静注后96h。血清中EB浓度在静注后3h内迅速减少,之后呈缓慢代谢过程,静注后24h减少到静注浓度的38%,静注后24h EB在血清和肿瘤组织中的浓度差达到最大值。染色后在手术显微镜下进行肿瘤切除手术操作较未染色对照组明显容易,手术后切片组织学观察肿瘤被完全切除。结论EB生物学染色标记脑内肿瘤效果可靠,手术中作为肿瘤的标示鉴别肿瘤和周围正常脑组织的界限有效。     

Alpha-Fetoprotein Subtractions in Germ Cell Tumors Identified by Con A or LCH Crossed-Line Affinity Immunoelectrophoresis

ABSTRACT: Using concanavalin A (Con A) crossed-line affinity immunoelectrophoresis and lentil lectin (LCH) crossed-line affinity immunoelectrophoresis, alpha-fetoprotein (AFP) subfractions were studied in sera including three sera from nude mice heterotran-splanted with human yolk sac tumor of the ovary and three sera from patients with yolk sac tumor, mature solid teratoma, or immature solid teratoma of the ovary. In sera of nude mice bearing yolk sac tumor or from a patient with yolk sac tumor, subfractions from yolk sac and those from fetal liver were identified. Since AFP subfractions from yolk sac and fetal liver can be differentiated according to the carbohydrate moieties, our findings indicate that AFP produced by yolk sac tumor and fetal yolk sac are to some extent differently glycosylated. We also found that AFP in both mature and immature solid teratoma was composed of two subfractions ontogenetically originating from yolk sac or fetal liver. All these findings indicate that more than two different factors are responsible for the AFP synthesis in germ cell tumor of the ovary.     

Diagnosis of Small Pancreatic Carcinoma

A retrospective analysis was performed to evaluate the clinicalsymptoms and abnormal test findings in small pancreatic carcinoma.Five hundred and thirty-six cases of pancreatic carcinoma withthe histology of duct cell carcinoma were collected from 14medical centers in Japan. In 440 of the cases, tumor size wasmeasured at the time of laparotomy or from the resected specimen.Three hundred and seventy-seven patients (86%) had a carcinomalarger than 3.0 cm; only 30% of these were resectable. Sixty-threepatients (14%) had a carcinoma of 3.0 cm or less, with resectabilityof 97%. Detecting a tumor of "3 cm or less" with a high probabilityof resectability is the objective of early diagnosis with theresulting possibility of a cure. In most cases these small carcinomaswere found easily when obstructive jaundice was present (73%).However, the estimated occurrence of obstructive jaundice associatedwith carcinomas of 3 cm or less was only 10% among the totalcases of pancreatic carcinoma studied. Therefore, it is necessaryfor early diagnosis to detect carcinomas of 3 cm or less presentingwithout jaundice. The symptoms of small carcinoma without jaundiceare weight loss, anorexia, upper abdominal pain, back pain anda palpable abdominal mass. Among the various available examinations,endoscopic retrograde cholangiopancreatography, computerizedtomography and ultrasonography were valuable in diagnosing thesesmall carcinomas.     

Studies on Duodenal Cyclic AMP Content in Pancreatic Disease after Administration of Pancreozymin and Secretin

Cyclic AMP (cAMP) output in the duodenal contents of 11 normal subjects, 18 patients with chronic pancreatitis, six convalescing from acute pancreatitis and five with pancreatic carcinoma was measured after a single dose of pancreozymin and secretin. The technic was indirect, utilizing recovery of duodenal contents by the Dreiling tube rather than direct measurements of fluid that was not contaminated by bile. In all patients groups, cAMP output reached a peak after this stimulation with a concomitant increase of bicarbonate and amylase outputs. A significantly decreased cAMP output was observed in all pancreatic disease groups compared to the normal group. Patients with chronic pancreatitis showed a slightly decreased cAMP output, considerably decreased bicarbonate output and normal amylase output. In acute pancreatitis cAMP output was reduced with normal bicarbonate and amylase outputs. In pancreatic carcinoma cAMP decreased significantly, bicarbonate output was moderately reduced and amylase output was normal. cAMP output in all groups studied did not correlate with either bicarbonate output or amylase output.