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S Tanaka

Publications and source records attributed to S Tanaka.

At least 253 records · Page 14Linked to original sources
PubMed2001

Repeat hepatectomy is the most useful treatment for recurrent hepatocellular carcinoma.

Hepatic resection has been regarded as a curative treatment for primary hepatocellular carcinoma (HCC), but a high incidence of postoperative recurrence is general. Thus it is important to predict the patterns of recurrence and select the appropriate treatment for recurrence for a better long-term prognosis of patients with HCC. Clinicopathological studies on 80 patients with intrahepatic recurrence after curative hepatectomy suggested that nodular-type recurrence with up to three nodules is mainly due to metachronous multicentric hepatocarcinogenesis rather than intrahepatic metastases. We reviewed 300 patients with recurrent HCC, and repeat hepatectomy was done in 78 cases (26.0%). The 3- and 5-year survival rates after repeat hepatectomy were 82.8% and 47.5%, respectively, showing better prognosis than those for other treatments. Repeat hepatectomy is the preferred treatment offering a hope of long-term survival for patients with recurrent HCC as long as liver function is sufficient; thus early detection of recurrence should be ensured.

Adult↗
PubMed2001

A low 13C-urea breath test value is associated with increased risk of gastric cancer.

PURPOSE: The 13C-urea breath test (UBT) is considered to be the most accurate way of diagnosing Helicobacter pylori infection. Values are affected by H. pylori infection and by the severity of atrophic gastritis. Our objective was to determine the association of UBT values with gastric cancer, and to evaluate the risk of gastric cancer in terms of UBT values. METHODS: Our study involved 413 consecutive patients who had undergone esophagogastroduodenal examination and the UBT test. RESULTS: Of the 398 patients with positive UBT results, atrophy and intestinal metaplasia scores in both antrum and corpus were significantly higher in patients with gastric cancer than in those with gastritis, duodenal ulcer, and gastric ulcer. The UBT value related to gastric cancer (22.01 +/- 1.89%o) was significantly lower than that for gastritis (35.19 +/- 1.53%o; P < 0.01), duodenal ulcer (29.01 +/- 1.97%; P < 0.05), or gastric ulcer (30.79 +/- 2.83%; P < 0.05). When the UBT values were less than 20%, increases in the risk of gastric cancer correlated with decreasing UBT values. CONCLUSIONS; These findings indicate that the UBT value related to gastric cancer is significantly lower than that for gastritis, duodenal ulcer, or gastric ulcer in H. pylori-positive patients. Low UBT values were associated with the risk of gastric cancer.

Biopsy↗
PubMed2001

Prediction of the postoperative pulmonary function and complication rate in elderly patients.

We analyzed the risk factors predisposing elderly patients to develop postoperative respiratory complications (PRCs) and investigated the possibility of predicting the postoperative pulmonary function and PRC rate. The postoperative pulmonary functions were predicted according to a simplified system, which we developed using plain chest roentgenograms from patients with primary lung cancer. Both univariate and multivariate analyses of PRCs were performed in 39 elderly patients with lung cancer from July 1982 to March 1991 (the early period). Based on the results obtained, the permissible extent of lung resection to achieve a predicted postoperative % forced expiratory volume in 1 s (ppo%FEV1.0) and a predicted postoperative % vital capacity (ppo%VC) of more than 55% was selected as the basic criteria for undergoing such an operation after April 1991 (the recent period). A ppo%FEV1.0 and/or ppo%VC of 55% or less was the most significant risk factor for developing PRCs. The PRC rate decreased from 33.3% to 9.8% (P = 0.0251) and the operative mortality rate decreased from 10.3% to 0%. The survival rates for stage I, II. and III cases were not significantly different between the early and recent periods. Decisions made on the operability and the permissible extent of lung resection based on our system using plain chest roentgenograms therefore appeared to reduce the PRC rate and operative mortality rate in elderly patients.

Aged↗
PubMed2001

The role of macroscopic classification in nodular-type hepatocellular carcinoma.

BACKGROUND: Little has been reported on the role of macroscopic classification of hepatocellular carcinoma (HCC). We hypothesized that macroscopic classification of HCC might have a strong correlation with long-term prognosis after hepatectomy. METHODS: Four hundred and four patients with a macroscopically nodular type of HCC who underwent a hepatectomy were studied. The patients were divided into three groups: single nodular (SN) group (n = 312); single nodular with extranodular growth (SNEG) group (n = 52); and confluent multinodular (CMN) group (n = 40). Clinicopathological variables were compared among the three groups. The patient survival rate was also compared among the three groups. Finally, a multivariate analysis was performed to clarify the independent significant variables of the long-term prognosis. To confirm the consistency of the results in small-size HCC, the same analyses were made using patients whose tumor size was equal to or less than 3 cm in diameter. RESULTS: The alpha-fetoprotein value, tumor size, and rate of absolute noncurative operation in the SNEG group were higher than in other groups. The positive rate of both portal vein invasion of cancer cells and intrahepatic metastasis in the SN group was lower than those in other groups. The rate of poorly differentiated histology in the SN group was lower than in the other groups. Patient survival in the SNEG group was worst among the three groups. However, patient survival showed no significant difference between the SN and CMN groups. The multivariate analysis showed that the presence of intrahepatic metastasis, the macroscopic classification of SNEG type, and absolute noncurative operation were independent poor prognostic indicators. The results for patients with small HCCs measuring equal to or less than 3 cm in diameter were quite similar to the results for the other patients. CONCLUSIONS: Among the three subtypes of macroscopically nodular type of HCCs, the SNEG type showed higher rates of portal vein invasion of cancer cells, intrahepatic metastasis, and poorly differentiated histology. The patient survival rate in the SNEG type was worst, and the SNEG type was an independent poor prognostic indicator. The macroscopic classification of HCC, especially the SNEG type, helps predict the long-term outcome after hepatectomy.

Carcinoma, Hepatocellular↗
PubMed2001

Serial change in the atrial transport function after the radial incision approach.

BACKGROUND: The left atrial transport function recovers slowly over several months after the maze procedure (Maze), but remains at a low level even during the long-term postoperative period. Because the Maze leaves an insufficient left atrial transport function, patients may still be prone to thromboembolism after the Maze. The radial incision approach (Radial) has been shown to preserve greater atrial transport function than does the Maze in the early postoperative period. METHODS: To examine the serial change in the atrial transport function after the Radial, out of 32 patients who underwent the Radial, 15 patients were assessed by transthoracic Doppler echocardiography 1, 3, 6, and 12 months after surgery. The atrial filling fraction and peak A/E velocity ratio were determined from the flow-velocity spectra across the mitral and tricuspid valves. The incidence of thromboembolic events was examined in 21 patients who were followed for more than 3 months after the Radial. The data were compared with data obtained from 13 patients after (41 +/- 6 months) the Maze III procedure. RESULTS: The left atrial transport function after the Radial increased within 3 months to a significantly greater level than did that after the Maze in the longterm. The atrial filling fraction was 28.2% +/- 7.9% at 3 months after the Radial and 15.1% +/- 4.0% at 41 months after the Maze (p < 0.01). The peak A/E ratio was 0.52 +/- 0.18 at 3 months after the Radial and 0.25 +/- 0.07 at 41 months after the Maze (p < 0.01). This increased atrial transport function was maintained for an extended period after the Radial. There were no thromboembolic events in any of the patients after the Radial or Maze, irrespective of postoperative anticoagulant therapy. CONCLUSIONS: The Radial approach prevents thromboembolism by restoring sufficient atrial transport function more effectively and faster than does the Maze.

Aged↗
PubMed2001

Reduction in recalcitrant pulmonary hypertension after operation for atrial septal defect.

We present the case of a patient with atrial septal defect and severe pulmonary hypertension with pulmonary artery peak pressure greater than 110 mm Hg. Open lung biopsy was done prior to the corrective operation, and pathological findings in the small pulmonary arteries included "musculoelastosis" and complete occlusion of 70% of these small arteries and arterioles. The atrial septal defect was closed, and long-term oral prostacyclin therapy was initiated. Pulmonary artery peak pressure decreased to 65 mm Hg 2 years after the operation. This case demonstrates that in a patient with 70% complete occlusion of small pulmonary arteries and arterioles resulting from "musculoelastosis," not only is surgical intervention possible but also pulmonary artery pressure decreases in the long term after operation.

Adult↗
PubMed2001

Limited flow capacity of the right gastroepiploic artery graft: postoperative echocardiographic and angiographic evaluation.

BACKGROUND: The flow capacity of the right gastroepiploic artery graft has not been clarified. METHODS: Angiographic and echocardiographic studies were conducted in 30 patients who had undergone coronary artery bypass grafting using both the internal thoracic and right gastroepiploic arteries. The luminal diameter of the arterial grafts was measured from the postoperative angiograms. The adequacy of the myocardial blood supply from the arterial grafts was evaluated by dobutamine stress echocardiography. RESULTS: With echocardiography, 14 patients exhibited an ischemic response in the gastroepiploic artery grafted region, whereas no patients exhibited an ischemic response in the internal thoracic artery grafted area. The luminal diameter of the gastroepiploic artery and a younger age were correlated with the ischemic response observed in the dobutamine stress echocardiography. A luminal diameter of the gastroepiploic artery of greater than 2.6 mm had the highest sensitivity and specificity for a nonischemic change. CONCLUSIONS: To generate the maximal flow reserve, the luminal diameter of the gastroepiploic artery when used as a graft should be sufficiently large enough, nearly 3 mm at the anastomosis.

Aged↗
PubMed2001

Sequential grafting of the right gastroepiploic artery in coronary artery bypass surgery.

BACKGROUND: Only a few studies have been done on sequential grafting using the right gastroepiploic artery (GEA). METHODS: Forty patients (35 males, ages 36 to 74 years) who underwent sequential grafting of the GEA were reviewed. Angiography of the GEA was performed preoperatively in all patients. GEAs with a luminal diameter greater than 2 mm at the presumptive distal anastomosis on the angiogram were used. The dissected GEA was led into the pericardial cavity through the antegastric route. We used GEAs to graft 89 branches (2.2 per patient) in the inferoposterior region. RESULTS: In 24 patients who had angiographic examinations, all the GEAs were patent, although luminal narrowing was noted in the segment between the two anastomoses in 3 patients. Eight-year actuarial survival was 92.5% and the cardiac-related event-free rate was 95%. CONCLUSIONS: Sequential grafting of the GEA can be performed effectively in selected patients. Performing preoperative angiography to assess the size of the GEA for sequential grafting is strongly recommended.

Adult↗
PubMed2001

Adequacy of flow capacity of bilateral internal thoracic artery T graft.

BACKGROUND: With the T graft configuration, multiple arterial revascularization can be accomplished using bilateral internal thoracic arteries. However, concern remains about the flow capacity of the main stem of the left internal thoracic artery (LITA). METHODS: Forty patients who underwent multiple revascularization of the entire territory of the left coronary system with a T graft were investigated. Six months after the operation, they were examined angiographically. During the same period, dobutamine stress echocardiography was performed to evaluate the adequacy of the myocardial blood supply from the T graft. The T graft revascularized two branches in 5 patients, three branches in 23, four branches in 11, and five branches in 1 of the left coronary system. Other conduits were used if revascularization was required for the right coronary system. RESULTS: Complete revascularization was achieved in the left coronary territory in all patients. The LITA main stem showed a wide lumen in all patients. Luminal narrowing was present in the distal segment of the LITA in 3 patients. The right internal thoracic artery (RITA) was patent in all patients, whereas luminal narrowing was observed in the distal segment of the RITA in 5 patients. No patient exhibited ischemic wall motion abnormality in the anteroseptal, lateral, or posterolateral region of the left ventricle where the T graft revascularized. Eight patients showed ischemic response in the inferoposterior region, that is, the territory of the right coronary artery. CONCLUSIONS: The LITA main stem, forming a T-graft configuration with the free RITA, has an adequate flow reserve to supply at least the entire left coronary arterial system with sufficient blood. Therefore, multiple coronary revascularization using the T-graft technique is feasible.

Aged↗
PubMed2001

Electrochemical oxidation of bisphenol A. Application to the removal of bisphenol A using a carbon fiber electrode.

The electrochemical behavior of bisphenol A was investigated by voltammetric techniques. The electrochemical oxidation of bisphenol A led to the inactivation of the glassy carbon electrode as the result of the deposition of the electropolymerized films. Although phenolate is oxidized more easily than the neutral phenol, an electropolymerized film of bisphenol A was formed in neutral media rather than in alkaline media. The fouling of the electrode surface by the electropolymerized film was evaluated by monitoring the electrode response of ferrocyanide ion as the redox marker. The electrochemical removal of bisphenol A based on the formation of the electropolymerized film on an anode surface was also attempted using a carbon fiber electrode with a very large surface area. The high removal efficiency for bisphenol A was obtained in a dilute solution of bisphenol A. The maximum surface coverage (gamma) of electropolymerized bisphenol A on the carbon fiber was about 2 x 10(-9) mol/cm2.

Benzhydryl Compounds↗
PubMed2001

Corneal irregular astigmatism and contrast sensitivity after photorefractive keratectomy.

OBJECTIVE: To investigate the relation between contrast sensitivity and corneal irregular astigmatism in eyes after photorefractive keratectomy (PRK). DESIGN: Prospective observational case series. PARTICIPANTS AND CONTROLS: Seventy-nine eyes without corneal haze 6 months or more after PRK and 30 normal control eyes. METHODS: Videokeratography was taken with TMS-1 (Computed Anatomy Inc. New York, NY), and contrast sensitivity for day and night vision was measured using a Multivision Contrast Tester 8000 (Vistech Consultants, Inc., Dayton, OH). MAIN OUTCOME MEASURES: Regular and irregular astigmatism (asymmetry and higher order irregularity components) were computed using Fourier series harmonic analysis of the videokeratography data. Area under the log contrast sensitivity function (AULCSF) was calculated from the contrast sensitivity data taken at five spatial frequencies. RESULTS: After PRK, AULCSFs were significantly smaller for day vision (P = 0.007, unpaired t test) and night vision (P = 0.020) compared with normal controls. AULCSFs for day vision were significantly negatively correlated with asymmetry (Pearson's correlation coefficient, R = -0.23, P = 0.049) and higher order irregularity (R = -0.33, P = 0.004) components but not with the regular astigmatism component (P > 0.3). AULCSF for night vision correlated significantly with asymmetry (R = -0.31, P = 0.013) and higher order irregularity (R = -0.30, P = 0.016) components but not with the regular astigmatism component (P > 0.3). CONCLUSIONS: Corneal irregular astigmatism after PRK significantly influences contrast sensitivity.

Adult↗
PubMed2001

Expressed emotion of families and the course of mood disorders: a cohort study in Japan.

BACKGROUND: Findings on expressed emotion (EE) of the family and the course of mood disorders have not been consistent. There has also been no report on these problems from Asia. METHODS: The subjects were 32 patients diagnosed to have mood disorders on the basis of DSM-IV and ICD-10 and 36 principal members of their families. EE was evaluated using Camberwell Family Interview (CFI). A cohort study was conducted for 9 months after discharge of the patients. The patients were divided into a high-EE group and a low-EE group using a few cut-off points concerning the number of critical comments (CCs) and emotional over-involvement (EOI), the 9-month relapse risks were compared, and the relapse risk ratio and its 95% confidence interval were calculated. Also, the sensitivity, specificity, positive predictive value, and negative predictive value were calculated, and the optimal cut-off point was evaluated. Multiple logistic regression analysis was performed to control the effects of potential confounding factors. RESULTS: When the subjects with three or more CCs, or an EOI score of three or higher were regarded as a high-EE group, and the others as a low-EE group, the nine-month relapse risks were 83.3% (5/6) and 19.2% (5/26), respectively, and the relapse risk ratio (95% confidence interval) was 4.3 (1.8-12.2). The values of the validity parameters were the highest with these cut-off points. The effect of EE was also significant on multiple logistic regression analysis. LIMITATIONS: Small sample size and severity of the patients. CONCLUSIONS: Families' EE based on CFI correlated with relapse also in Japan.

Adult↗
PubMed2001

Comparison of the lateral diffusion coefficient of hepatocyte plasma membrane proteins in three strains of sensescence accelerated mouse (SAM).

The lateral diffusion coefficients of proteins (D(p)) were measured in hepatocyte plasma membrane in freshly prepared liver smears by means of the fluorescence recovery after photobleaching (FRAP) method. D(p) was measured after development of peroxide-induced autofluorescence (PIAF) in a total of 115 senescence accelerated mice (SAM), distributed in three strains, at least five age-groups in each, as follows: (i) SAMR1TA (25 males and 22 females), medium life span (MLS) in months, under specific pathogen free (SPF) conditions, MLS(spf) 20.1 and 20.0, respectively, while under conventional conditions, MLS(Deltapf)=18.9 in average for both sexes; (ii) SAMP6/Ta (18 males and 17 females), MLS(spf)=17.1 and 15.3, respectively, and MLS(cc)=8.1 for both sexes; (iii) SAMP6/Ta (17 males and 16 females), MLS(spf)=15.6 and 14.7, respectively, and MLS(cc)=10.0 for both sexes. A highly significant negative linear age-correlation of D(p) (R=0.975 or higher) was found in each strain, being roughly proportional with the MLS(cc) values. Since the studied mice kept under SPF conditions survived longer, than under conventional conditions, the actual age-dependent decay rates of D(p) values did not differ significantly in two pairs of comparisons (female R1/P6 and female R1/P8), whereas they did in all other possible pairs, including also the normal C57BL/6 mice. The main conclusion can be drawn that the D(p) of hepatocyte membranes is a good biomarker of aging and survival also in SAM, as in all other inbred and outbred rodents, studied so far.

Journal Article↗
PubMed2001

A group of five parameters as a new biological marker on F344/N rats.

The National Institute for Longevity Sciences (NILS) established an aging farm (A/F) for producing aging/aged laboratory rodents at the Experimental Animal Facility Wing under the NILS A/F Guide planned by the Laboratory Animal Research Facilities (LARF). Five parameters, the average life span, the number of days of 75, 50, and 25% survival points, and average of the top 10 longest life span among laboratory strains of rodents at NILS-A/F, were reproducible for F344/N rats specifically by strain and sex under the LARF A/F guide. These five parameters may serve as an effective and practical biological marker, especially in aging science including longevity science, to evaluate characteristics of strains of laboratory rodents. The five parameters can identify clear substrain differences between F344/N and F344/Du and breeder differences between F344/DuCrj and F344/DuCrl.

Journal Article↗
PubMed2001

Differences in management and outcomes of acute myocardial infarction among four general hospitals in Japan.

OBJECTIVE: To ascertain the differences among hospitals in Japan in the management patterns and outcomes of patients with acute myocardial infarction (AMI). DESIGN: Retrospective cohort study by means of patient chart review. SETTING: Four tertiary-care teaching hospitals in Japan observed over a 1-year period. STUDY PARTICIPANTS: Consecutive patients (N=482) admitted for AMI. MAIN OUTCOME MEASURES: Clinical characteristics, rates of diagnostic and therapeutic procedures performed, cardiac complications, and length of stay. RESULTS: Patients' clinical characteristics differed significantly among the four hospitals in terms of age, gender, and prior cardiac history, but not in terms of comorbidity or infarct location. The frequency and type of diagnostic and therapeutic procedures were different, and in-hospital mortality varied (4-14%, P=0.022). Average length of hospital stay ranged from 15.8+/-12.6 days to 41.0+/-19.4 days (P=0.0001). After adjustment for the clinical characteristics, these differences remained significant among hospitals. CONCLUSION: Considerable differences in the management and outcomes of patients with AMI exist in Japan.

Aged↗
PubMed2001

The role of overexpression and gene amplification of cyclin D1 in intrahepatic cholangiocarcinoma.

BACKGROUND/AIMS: Intrahepatic cholangiocarcinoma (ICC) is a primary liver malignant tumor with an extremely poor prognosis, but less attention has been directed to factors related to molecular carcinogenesis, including cell cycle proteins. We examined the expression and gene amplification of cyclin D1, the cell cycle regulating protein. Our objective was to evaluate correlations with clinicopathological factors in ICC. METHODS: Cyclin D1 overexpression and cellular proliferative activity (Ki-67 labeling index) were investigated immunohistochemically, and 20 cases were further investigated for cyclin D1 gene amplification, using differential PCR. We examined the correlation between the expression and gene amplification of cyclin D1 and clinicopathological factors, including overall survival in patients with ICC. RESULTS: Immunohistochemical analysis revealed an overexpression of cyclin D1 protein in 28 of 66 subjects with ICCs (42%). The cyclin D1 overexpression was associated with poor histological differentiation (P = 0.04), high cellular proliferative activity (P < 0.01), and a poor prognosis (P = 0.02) by univariate analysis, although it is not an independent prognostic factor by multivariate analysis. Cyclin D1 gene amplification was confirmed in five of the 20 patients. Of those five cases of ICC, all had poor histological differentiation, and four of the five ICCs (80%) showed evidence of cyclin D1 immunoreactivity. CONCLUSIONS: Overexpression and gene amplification of cyclin D1 are frequent and contribute to dedifferentiation and cellular proliferative activity of ICCs, and overexpression also indicates a poor prognosis for patients with ICC.

Adult↗
PubMed2001

Newly discovered functions for some myotropic neuropeptides in locusts.

The field of neuropeptide research in insects during the past twenty years can be characterized by the enormous number of peptides that have been identified. In the locusts, Locusta migratoria and Schistocerca gregaria only, structural information is now available for more than 60 peptides. Quite a number of these peptides were isolated on the basis of their effect on visceral muscle contraction in vitro. A very limited number of reports describe the 'in vivo' function of a myotropic neuropeptide. Moreover, for most of the brain neuropeptides, we ignore whether they have a hormonal function. In this paper, we describe the recently discovered in vivo effects of some of the myotropic peptides, identified in locusts in the past decade. Schistocerca-neuropeptide F accelerates egg development; locustasulfakinin inhibits food intake and [His(7)]-corazonin induces body color pigmentation.

Animals↗