The electrochordographic study of the hemodynamics of the spinal cord.
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Biomedical subjects
Publications and source records attributed to Y Nimura.
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In 17 consecutive patients who underwent major hepatic resection, 9 of whom with combined resection of the gastrointestinal tract or the pancreatic head (or both), postoperative hepatic blood flow was investigated. In this study, the patients were classified into two groups according to their postoperative serum total bilirubin level: Group A comprised 7 patients with the level higher than 7 mg/dl for more than 1 week postoperatively, and group B comprised 10 patients who did not meet this criterion. For 2 weeks after surgery, the portal blood flow velocity, the hepatic artery resistive index (RI) calculated from the changes in Doppler frequency shifts, and the hepatic venous blood flow velocity were measured intermittently using color Doppler ultrasonography. Liver volume was assessed by computed tomography to provide the restoration. Significant differences in portal blood flow velocity and hepatic artery RI were noted between the two groups from the third postoperative day. In group A the portal blood flow velocity decreased below the preoperative value, and the hepatic artery RI increased above 0.75. In contrast, group B showed high portal blood flow velocity and low hepatic artery RI. In both groups the RI correlated significantly with the total bilirubin level (r = 0.74; p < 0.0001), and the growth rate of the remnant liver was proportional to the mean postoperative portal blood flow velocity (r = 0.70; p = 0.016). We concluded that measurement of the portal blood flow velocity and hepatic artery RI can be useful for predicting postoperative liver dysfunction and liver regeneration after major hepatic resection.
Two 5.5 French triple-lumen balloon catheters were devised to improve percutaneous transhepatic portal embolization (PTPE) as preoperative management of patients undergoing extensive liver resection. Using these catheters, an ipsilateral approach for embolization is achieved through a portal branch of the liver using fibrin glue mixed with Lipiodol as the embolic material. This approach proved safer and more reliable than the traditional contralateral approach: (1) The portal branch to be resected is punctured; (2) the left and right anterior portal embolization is conducted simultaneously through a single portal puncture; and (3) the catheter sheath can consequentially be removed soon after PTPE without requiring further treatment.
From 1979 through 1989, surgical resection was performed in 55 of 66 patients with carcinoma of the hepatic hilus after improving jaundice by percutaneous transhepatic biliary drainage (PTBD). Selective cholangiography through PTBD was done to define precisely the anatomical location--extent of the obstructing lesion in each segmental hepatic duct. Percutaneous transhepatic cholangioscopy was performed through the sinus tract of PTBD after replacing the drainage catheter with a 15 French catheter for superselective cholangiography and biopsy to make the definitive diagnosis of the histological extent of the tumor and any variation of each segmental hepatic duct that joins the hepatic hilus. In 46 (69.7%) of 66 patients, curative resection was possible. Forty-five of these underwent various types of hepatic segmentectomy with caudate lobectomy for a morbidity rate of 41.3% and an operative mortality rate of 6.4%. Fourteen (31.1%) advanced cases underwent combined resection of the portal vein together with hepatectomy. Microscopic tumor involvement in the caudate branches was confirmed in 44 of 45 patients who underwent caudate lobe resection. The 3-year survival rate for all 43 patients surviving the curative excision was 55.1% and the 5-year survival rate was 40.5%. All 11 patients who had an unresectable advanced tumor died within 9 months. Curative resection should be designed according to the preoperative findings of the extent of cancer in each segmental duct, and caudate lobe resection should be performed together with the smallest necessary hepatic segmentectomy possible.
Stepwise logistic and discriminant analyses were used to define the risk factors for hepatic failure after liver resection for carcinoma of the biliary tract and to predict this complication. The logistic analysis identified the linear pattern of oral glucose tolerance test, cholangitis, pancreatoduodenectomy, and indocyanine green disappearance rate as the factors most related to hepatic failure among 18 pre- and perioperative parameters of the past 84 hepatectomized cases (55 hilar bile duct carcinomas and 29 gallbladder carcinomas). Our discriminant formula using five variables, including the above-mentioned four plus the liver resection rate, could distinguish the patients with posthepatectomy liver failure (n = 25) from those without (n = 59) with 86.9% accuracy, 96.0% sensitivity, and 83.1% specificity. The cross-validation test has confirmed that this model was robust for discriminant analysis. The results of this study show that statistical multifactorial analysis makes possible the preoperative prediction of hepatic failure after liver resection for carcinoma of the biliary tract.
To evaluate the influence of various clinicopathologic factors on survival, a computer analysis was performed on 70 patients who underwent resection for bile duct carcinoma. Univariate analysis of overall survival involving all the patients identified 10 factors that were associated with a significant outcome: location of primary lesion (p = 0.01), pancreatic invasion (p = 0.004), duodenal invasion (p = 0.005), macroscopic and microscopic vascular involvement (p = 0.009 and p = 0.04), perineural invasion (p = 0.02), lymphatic vessel involvement (p = 0.04), lymph node metastasis (p = 0.02), histologic type (p = 0.02), and depth of cancer invasion (p = 0.04). However, when the interactive effects of these factors were taken into account, the pancreatic invasion and perineural invasion were selected as the two most significant prognostic factors in a multivariate analysis using the Cox stepwise proportional hazards model. The age, sex, size of the tumor, macroscopic type of lesions, hepatic infiltration, serosal invasion, resected surgical margin at the proximal and distal ends, exposed surgical margin, peritoneal dissemination, and hepatic metastasis were not significantly associated with prognosis.
We evaluated the clinicopathologic findings and surgical results of 140 patients with thoracic esophageal cancer treated at Shinshu University, Japan (Shinshu group), and compared them with those from 1164 patients treated at Hebei Medical College, China (Hebei group) to determine if the two groups showed any differences. The Shinshu group had significantly higher incidences of elderly patients (>70 years of age), male patients, and tumors located at the lower esophagus (p < 0.01). In the Hebei group, although the depth of tumor invasion was more advanced, the incidence of nodal metastasis was significantly lower (p < 0.01). Operative death and postoperative complications were more frequent in the Shinshu group. Comparison of the postoperative survival curves revealed significantly longer survival of patients with pT2 or pT3 tumor in the Hebei group (p < 0.01), but there were no significant differences between the two groups when the lesions were classified by pTNM stage. This study demonstrated several differences between the patients in the two areas in regard to the clinicopathologic characteristics of thoracic esophageal cancer. The most important characteristic of the esophageal cancer in the Hebei group appears to be the low incidence of nodal metastasis.
Pulsed Doppler echocardiography is a noninvasive method with high sensitivity and specificity for the assessment of tricuspid regurgitation. In patients with tricuspid regurgitation, pansystolic unusual Doppler signals are detected in the right atrial cavity, which are interpreted as tricuspid regurgitant flow signals. They distributed in a spindle-shaped area from the tricuspid orifice toward the right atrial posterior wall in parallel with the interatrial septum. The orientation of the range where the regurgitant Doppler signals are detected in the right atrial cavity shows the direction of the regurgitant jet. However, such a result is determined mainly in patients with functional tricuspid regurgitation. In regard to patients with organic tricuspid lesion, different considerations may be necessary. Semiquantitative grading of the severity of regurgitation is possible, based on the distance covered by the regurgitant signals from the tricuspid orifice. Tricuspid regurgitation is demonstrated also by contrast echocardiography. The severity is graded based on the distance reached by regurgitant curvilinear contrast echoes from the tricuspid valve in the M-mode echocardiography. If the ultrasound beam is adequately directed through the tricuspid orifice, the grade estimated by the contrast echoes are well correlated with that by the Doppler. However, if the M-mode is performed without the guide by the two-dimensional image, it may miss the most adequate beam direction for the observation, resulting in underestimating severity. The influences of tricuspid regurgitation are generally seen in the flow pattern of the major veins. However, they are more sharply reflected by the flow condition in the right atrial cavity than by the flows patterns in the major veins.
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Pericardial effect on left ventricular early filling was studied in six dogs by use of pulsed Doppler echocardiography. Rapid dextran infusion was used to manipulate left atrial pressure. Left ventricular peak early filling velocities before and after pericardiectomy were measured at different levels of left atrial pressure with right atrial and left ventricular pressures. Peak early filling velocity correlated with mean left atrial pressure before and after pericardiectomy. Before pericardiectomy, when mean right atrial pressure exceeded 12 mm Hg, further increase of the velocity was not observed in spite of volume loading. After pericardiectomy, peak early filling velocity became higher and the slope of the relation line between mean left atrial pressure and the velocity became steeper than before pericardiectomy. When the filling pressure was denoted by the transmural mean left atrial pressure, the points on the relation line before pericardiectomy fell along the relation line after pericardiectomy. We conclude the pericardium exerts an external constraint on left ventricular early filling. Therefore we should not consider the absolute but the transmural filling pressure when estimating left ventricular early diastolic function with use of Doppler-derived left ventricular early filling velocity.
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In this multicenter randomized trial, the efficacy of combination chemotherapy using 5-fluorouracil, doxorubicin and mitomycin C (arm A) was compared with that of 5-fluorouracil alone (arm B) in 81 patients with nonresectable carcinomas of the pancreas or biliary tract. There were no significant differences between treatment arms regarding the median time to progressive disease, median survival time, palliative effects or toxicities. It was concluded that combination chemotherapy is feasible but cannot be recommended.
We conducted a phase III randomized study to investigate effects of supportive chemotherapy with oral doxifluridine (group A, 75 patients) or 5-fluorouracil (group B, 75 patients) in advanced gastric cancer when intensive chemotherapy was not an option. Although there were no significant differences between the groups with regard to survival, hospital-free survival and time to progression, median values of 3 endpoints were superior in group A. Secondary analysis showed that group A patients with prior chemotherapy tended to have longer survival and hospital-free survival and significantly longer time to progression.
BACKGROUND/AIMS: The authors evaluated the influence of the vagal pyloric branches on the gastrointestinal function in patients who underwent a pylorus preserving pancreatoduodenectomy (PPPD). METHODOLOGY: Twenty-seven patients with pancreatobiliary and duodenal diseases underwent a PPPD between 1991 and 1994. We analyzed several variables including the daily volume of gastric juice, days of gastric suctioning, start of diet, gastric acid, and gastrin levels. In addition, a gastric emptying scintigram and gastrointestinal manometry were measured. These variables were compared between two groups, namely, those with retained superior pyloric branches of the vagus nerve (preserved group: n = 14), and those without these branches (non-preserved group: n = 13). RESULTS: There were no significant differences in basal acid output, maximum acid output, or plasma gastrin levels between the preserved group and the non-preserved group. In addition, a gastric emptying scintigram demonstrated no difference between the two groups. Finally, on gastrointestinal manometry, there was no significant difference between the two groups during gastric and jejunal phase III activity of migrating motor complex. CONCLUSIONS: Preservation of the vagal pyloric branches did not influence gastric exocrine and endocrine secretion, nor did it effect the gastric emptying of patients who underwent a PPPD.
BACKGROUND/AIMS: To clarify a correlation between serum alkaline phosphatase (ALP) levels and liver function and regeneration after major hepatectomy. METHODOLOGY: Post-operative changes in serum ALP levels were retrospectively examined in 91 non-cirrhotic patients with biliary tract carcinoma who underwent right hepatic lobectomy or more extensive liver resection. In addition, changes in liver volume after resection were assessed in 31 patients who underwent computed tomography before surgery and within 1 month after resection. RESULTS: Serum ALP levels reached its nadir on post-operative day 1, followed by a gradual increase until post-operative day 28. In patients with post-hepatectomy liver failure (n = 32), serum ALP levels were significantly lower on days 1, 7, 10, 14, 21, and 28 after resection than in those without such failure (n = 59). Unexpectedly, the volumetric study of the liver showed no significant difference between the two groups in the remnant liver volume after resection. CONCLUSIONS: Serum ALP levels can function as an indicator of liver function after hepatectomy, but not reflect morphological regeneration of the liver. Thus, increased ALP levels after hepatectomy may not reflect the cellular proliferation process itself.
BACKGROUND/AIMS: Vascular endothelial growth factor (VEGF) plays a key role in tumor angiogenesis. The aim of this study was to clarify the significance of VEGF expression in esophageal squamous cell carcinoma (SCC). METHODOLOGY: Tissues samples were taken from 52 patients with esophageal SCC after surgery. VEGF expression in these SCCs was examined immunohistochemically. Microvessels in the tumor stained for Factor VIII-related antigen were counted. Ki-67 antigen as a proliferative marker was immunostained with MIB-1, and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate biotin nick end labeling was performed for the evaluation of apoptosis. Ki-67 labeling index (LI) and apoptotic index were then calculated. RESULTS: VEGF expression was observed in 30 of the patients (57.7%). The microvessel count was significantly higher (p = 0.007), and the apoptotic index was significantly lower (p < 0.0001) in the SCC with VEGF expression than in the SCC without it, but no significant difference was observed in the Ki-67 LI between these groups. There was an inverse correlation between the microvessel count and the apoptotic index (p = 0.007). In the clinicopathologic factors, histologic venous invasion of cancer cells (p = 0.039) and lymph node metastasis (p = 0.049) were significantly correlated with VEGF expression. The survival rate after curative surgery was better in the patients without VEGF expression (p < 0.05), and distant organ metastasis after surgery was frequently observed in the patients with VEGF expression (p = 0.023). CONCLUSIONS: These results suggest that VEGF expression is associated with angiogenesis in esophageal SCC, and may be a prognostic factor in patients with esophageal SCC. Furthermore, apoptosis may be influenced by angiogenesis in esophageal SCC.
BACKGROUND/AIMS: The aim of this study was to clarify risk factors associated with intra-operative blood loss in hepatectomized patients with giant cavernous hemangioma (GCH) of the liver. METHODOLOGY: Twenty patients with GCH of the liver were treated by hepatectomy. Eleven patients with intra-operative blood loss > 2000 ml (mean: 7145 +/- 7080 m; Group 1) were reviewed retrospectively and compared to 9 patients with intra-operative hemorrhage < 2000 ml (mean: 918 +/- 429 ml; Group 2). RESULTS: Although there were no significant differences in pre-operative AST, ALT, and ICG-15 or fibrinogen and platelets between the two groups, pre-operative total bilirubin and fibrin degradation product (FDP) in Group 1 was significantly higher than in Group 2. Mean operation time and intra-operative blood transfusion in Group 1 versus Group 2 were 433 min vs. 213 min (p < 0.0001) and 3036 ml vs. 422 ml (p = 0.0072), respectively. The weight of resected liver (r = 0.821, p < 0.0001), maximum diameter of tumor (r = 0.782, p < 0.0001) and operation time (r = 0.748, p < 0.0001) were the most highly correlated with intra-operative blood loss, followed by pre-operative total bilirubin (r = 0.605, p = 0.0038), FDP level (r = 0.576, p = 0.0068) and intra-operative blood transfusion (r = 0.561, p = 0.0089). CONCLUSIONS: These findings suggest that pre-operative management to reduce the tumor size, total bilirubin and FDP levels may be essential to minimize intra-operative hemorrhage and blood transfusion.