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Toshio Imada

Publications and source records attributed to Toshio Imada.

At least 37 records · Page 2Linked to original sources
PubMed2004

Elevated resistive index in the hepatic artery as a predictor of fulminant hepatic failure in patients with acute viral hepatitis: a prospective study using Doppler ultrasound.

To assess the sensitivity and specificity of the resistive index of the hepatic artery, which is related to the vascular resistance of the artery, for the prediction of fulminant hepatic failure, we performed Doppler ultrasonography examinations on the hepatic arteries of 72 patients with acute viral hepatitis (25 of whom developed fulminant hepatic failure and 47 of whom recovered without developing fulminant hepatic failure) as well as the hepatic arteries of age- and sex-matched controls. The mean resistive index of the hepatic arteries in patients who developed fulminant hepatic failure was significantly larger than that of patients who recovered without developing fulminant hepatic failure (P < 0.01). When a resistive index cutoff level of 0.74 was used, an 84% sensitivity and a 94% specificity were obtained for the prediction of fulminant hepatic failure. An elevated resistive index of the hepatic artery may be useful for predicting the patient's clinical outcome and determining the need for a liver transplantation in patients with acute viral hepatitis.

Acute Disease↗
PubMed2004

Video-assisted thoracoscopic esophagectomy with a voice-controlled robot: the AESOP system.

The authors attempted to clarify the feasibility and safety of thoracoscopic esophagectomy with a voice-controlled robot, the AESOP system (3000 HR), and further determine whether innovative surgical equipment could allow the performance of complex thoracoscopic esophagectomy. Thoracoscopic surgery with a voice-controlled robot system has already been used in single-surgeon lung resection. Intra-operative and postoperative outcomes were compared between patients receiving hand-assisted laparoscopic surgery (HALS) and video-assisted thoracoscopic surgery (VATS) with the AESOP system (n = 15) and patients receiving open surgery (n = 30). In the AESOP group, the volume of blood loss was significantly less, but the total operation time was longer than in the open group. There were no significant differences in postoperative outcomes or the incidences of morbidity and mortality between the two groups. The surgeon using the AESOP system could obtain a stable, close-up, and long-lasting operative view. Laparoscopic and thoracoscopic surgery with the AESOP system has the potential to enable a single surgeon to perform a complex surgical procedure like esophagectomy.

Carcinoma, Squamous Cell↗
PubMed2004

Compositional changes of the muscular layers of the stomach with aging.

To elucidate compositional changes of the stomach with aging, the authors investigated age-related changes of the elements and relationships among the elements in the muscular layers of the pylorus, cardia, lesser curvature, and greater curvature by inductively coupled plasma-atomic emission spectrometry. After ordinary dissection by medical students, the pylori, cardias, lesser curvatures, and greater curvatures were removed from the subjects, consisting of 19 men and 1 woman, ranging in age from 65 to 95 yr. The muscular layers were isolated and the element contents were determined. The calcium content increased progressively with aging in the muscular layers of the pylorus, cardia, and lesser curvature, whereas it tended to increase in the muscular layer of the greater curvature with aging. Regarding sulfur, the content increased significantly in the muscular layer of the pylorus with aging, but not significantly in the muscular layers of the cardia, lesser curvature, and greater curvature with aging. Regarding the relationships among the elements, significant direct correlations were found among calcium, phosphorus, sulfur, and magnesium in both the muscular layers of the pylori and cardias, with some exceptions.

Aged↗
PubMed2004

Contrast-enhanced sonography of autoimmune pancreatitis: comparison with pathologic findings.

OBJECTIVE: We evaluated the vascularity of autoimmune pancreatitis lesions on contrast-enhanced harmonic gray scale sonographic images in comparison with the pathologic findings. METHODS: Six patients with autoimmune pancreatitis were examined. All patients held their breath from 20 to 50 seconds after the injection of a contrast agent while the vascularity of the lesion was examined by contrast-enhanced harmonic gray scale sonography (early phase), and lesion enhancement was monitored at about 90 seconds after the injection while the patients held their breath for a few seconds (delayed phase). We then compared the vascularity on the contrast-enhanced harmonic gray scale sonographic images with the pathologic findings (fibrosis and inflammation) in all lesions. The vascularity of 3 of the 6 lesions was also evaluated by contrast-enhanced harmonic gray scale sonography before and after treatment with corticosteroids. RESULTS: The autoimmune pancreatitis lesions exhibited mild (n = 1), moderate (n = 3), or marked (n = 2) enhancement throughout almost the entire lesions in both the early and delayed phases. The grade of lesion vascularity on the contrast-enhanced harmonic gray scale sonographic images correlated with the pathologic grade of inflammation and inversely correlated with the grade of fibrosis associated with autoimmune pancreatitis. The vascularity of all 3 lesions had decreased on the contrast-enhanced harmonic gray scale sonographic images after steroid therapy. CONCLUSIONS: Contrast-enhanced harmonic gray scale sonography may be useful for evaluating the vascularity of autoimmune pancreatitis lesions and the therapeutic efficacy of steroid therapy.

Aged↗
PubMed2004

Expression of survivin mRNA associates with apoptosis, proliferation and histologically aggressive features in hepatocellular carcinoma.

The clinical impact of survivin on human cancer pathogenesis and prognosis has been investigated. To clarify the clinical effect of survivin on tumor behavior and prognosis of patients with hepatocellular carcinoma (HCC), the expression of survivin mRNA in 40 samples of HCC tissue and matched-adjacent liver tissue, as well as 7 healthy hepatic tissue samples were measured by a real-time reverse transcription polymerase chain reaction. The expressed level of survivin mRNA (log copies/microg total RNA) in healthy liver tissue was 1.95+/-0.44, in morbid liver tissue adjacent to the tumors was 4.79+/-0.96, and in HCC tissue was 5.87+/-0.73 (values are mean +/- SD and P<0.001). The amount of survivin mRNA in HCC tissues correlated negatively with the apoptotic indices (r=-0.573 and P<0.001) and correlated positively with the proliferation indices (r=0.433 and P=0.005). Expression of survivin was significantly related with histologic grade (P=0.011) and pathological tumor stage (P=0.017). Patients with HCC tumors that had a large amount of survivin mRNA (> or = mean) had lower survival rate (P=0.030), but multivariate analysis showed only Ki-67 labeling index, histologic grade, and pathologic T stage to be the independent prognosticators. These findings indicate that survivin is associated with reduced tumor cell apoptosis, increased tumor cell proliferation, and histologically aggressive tumor features, and may play an important role in tumor progression of HCC. However, further examination is needed to clarify its predictive significance for HCC patients.

Aged↗
PubMed2004

[Radiofrequency ablation combined with transcatheter arterial chemoembolization for hepatocellular carcinoma--CT examination during the follow-up period].

Radiofrequency ablation (RFA) combined with transcatheter arterial embolization (TAE) can increase the volume of coagulation necrosis to treat patients with hepatocellular carcinoma. Furthermore, in clinical practice, RFA combined with TAE using iodized oil and gelatin sponge often induced the sub-segmental or segmental necrosis toward the liver periphery of the ablated lesion. In this study, we compared the CT findings and histological characteristics of peripherally spreading necrosis induced by this combination therapy for 12 patients with hepatocellular carcinoma. In all cases, complete necrosis of ablated lesions and peripherally spreading necrotic areas were confirmed by CT examination. The histochemical (lactate-dehydrogenase, maleate-dehydrogenase, and NADPH-diaphorase) stained specimens, biopsies from ablated lesions and peripherally spreading necrotic areas, were absent suggesting a 100% cellular destruction. No incomplete local treatments after the therapy were obtained during the 4-26 months of follow-up periods. We conclude that RFA combined with TAE using iodized oil and gelatin sponge makes it possible to induce the segmental or sub-segmental necrosis including tumors.

Aged↗
PubMed2003

Longterm control of advanced and recurrent gastric cancer (ARGC) by S-1.

BACKGROUND: An oral tegafur compound, S-1 (TS-1), was developed to potentiate antitumor activity and to reduce gastrointestinal toxicities for patients with gastric cancer. It has achieved a high response rate against advanced and recurrent gastric cancer (ARGC) in Japan; however, the efficacy and adverse reactions of longterm administration of S-1 remain to be elucidated. METHODS: Sixty-nine patients with ARGC treated with S-1 were studied; 58 patients had measurable lesions, while 11 patients did not. S-1 was orally administered at doses of between 40 and 60 mg/body twice daily for 28 days, followed by 14 days' rest, as one course. RESULTS: The overall response rate was 38% (complete response [CR], 2/58; partial response [PR], 25/58; stable disease [SD], 9/58 progressive disease [PD] 23/58). Response rate by target organ was 40% for the primary lesion, 45% for lymph node metastasis, 38% for peritoneal metastasis, and 25% for liver metastasis. When S-1 was administered as second-line chemotherapy (n = 25), the response rate was 36%. Of the 69 patients, 14 received S-1 for more than a year. The median survival time (MST) after S-1 administration in these 14 patients, including 3 patients with stable disease, was 918 days (range, 536 to 1107 days). There were no grade 3 to 4 toxicities in these 14 patients receiving longterm therapy with S-1. CONCLUSION: S-1 therapy was performed with a high response rate, irrespective of the target organ or the presence of prior chemotherapy. Longterm administration of S-1 may benefit patients with ARGC, providing prolonged disease control with acceptable toxicities.

Adult↗
PubMed2003

Contrast-enhanced harmonic gray-scale sonographic-histologic correlation of the therapeutic effects of transcatheter arterial chemoembolization in patients with hepatocellular carcinoma.

OBJECTIVE: We evaluated the usefulness of contrast-enhanced harmonic wideband gray-scale sonography in the assessment of the therapeutic effects of transcatheter arterial chemoembolization in patients with hepatocellular carcinoma and compared the performance of this imaging modality with the histologic findings for the patients. SUBJECTS AND METHODS: Twenty-nine patients with 29 hepatocellular carcinoma lesions were examined. Tumor vascularity was evaluated before and 7 days after transcatheter arterial chemoembolization with contrast-enhanced harmonic wideband gray-scale sonography performed after injection of the contrast agent Levovist. Several biopsy specimens were obtained from the evaluated lesions, and the histologic findings were compared with the results of contrast-enhanced sonography. RESULTS: Contrast-enhanced harmonic wideband gray-scale sonography performed after transcatheter arterial chemoembolization showed tumor vascularity in 16 of the 29 lesions, but none in the other 13 lesions. At histologic examination, 13 of the 16 lesions with tumor vascularity had residual tumor revealed, and the 13 lesions without tumor vascularity were found to have no histologically evident tumor residue, although three of these lesions showed tumor progression detected on CT during a 9- to 12-month follow-up period. Contrast-enhanced harmonic wideband gray-scale sonographic images were compared with the histologic findings as the gold standard, and the sensitivity and specificity of these images for discerning viable and nonviable hepatocellular carcinoma after transcatheter arterial chemoembolization were 100% and 81%, respectively. CONCLUSION: Contrast-enhanced harmonic wideband gray-scale sonography is potentially useful for evaluating the therapeutic effects of transcatheter arterial chemoembolization on hepatocellular carcinoma.

Aged↗
PubMed2003

[A case of metastatic gastric cancer responding to weekly administration of paclitaxel as a second-line therapy].

We report a 65-year-old man who underwent distal gastrectomy for advanced and metastatic gastric cancer in June 2000. TS-1 was administered for remnant metastatic lesions as first-line chemotherapy, but a recurrence was found in June 2001. Paclitaxel 80 mg/m2 was then administered weekly in a 1-h infusion on day 1, 8, and 15 as one cycle. After two cycles of paclitaxel administration, the patient was relieved from abdominal pain, and a barium enema revealed marked improvement of the colonic stenosis due to the peritoneal metastasis. There have been few effective chemotherapeutic agents against peritoneal metastasis from gastric cancer to date; however, a weekly paclitaxel regimen is considered to be one of the promising regimens for metastatic and recurrent gastric cancer.

Antineoplastic Agents, Phytogenic↗
PubMed2002

In-vitro effect of a combination of 5-fluorouracil (5-FU) and cisplatin (CDDP) on human gastric cancer cell lines: timing of cisplatin treatment.

BACKGROUND: To date, we have few effective chemotherapeutic agents against advanced and recurrent gastric cancer. 5-Fluorouracil (5-FU) and cisplatin (CDDP) are the most widely used drugs, and their combination has demonstrated favorable outcomes. However, the method (especially the timing) of CDDP administration is not well established. METHODS: We examined the in-vitro effect of a combination of 5-FU and CDDP on four human gastric cancer cell lines: MKN-1, MKN-28, MKN-45, and MKN-74. The cell lines were exposed to 50% of the inhibitory concentrations of 5-FU and CDDP for 72 h and 8 h, respectively. CDDP was applied before, simultaneously with, and after the start of treatment with 5-FU. RESULTS: When CDDP was applied after 5-FU, the cytotoxic activity against MKN-28, MKN-45, and MKN-74 was significantly potentiated. Against MKN-1, the earlier the initiation of CDDP treatment, the stronger was the cytotoxic effect. CONCLUSION: Our results suggest that the cytotoxicity of a combination of 5-FU and CDDP against human gastric cancer cells is both cell-line- and schedule-dependent and is especially affected by the timing of the CDDP treatment.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2002

Osteoclast-like giant cell tumor of the pancreas.

A rare case of osteoclast-like giant cell tumor of the pancreas is reported. A 45-year-old woman presented with upper abdominal pain and weight loss. Examination revealed a tumor in the tail of pancreas, and distal pancreatectomy with splenectomy was performed. Pathological findings showed the tumor was composed of two cell types: atypical mononuclear round cells and abundant osteoclast-like multinucleated giant cells with central nucleoli. Immunohistochemical study showed that the atypical cells were strongly reactive for vimentin and negative for CD68, while the giant cells were immunoreactive for CD68, but negative for vimentin. The tumor was diagnosed as osteoclast-like giant cell tumor of the pancreas. We report this case and review 31 cases previously described in the literature.

Female↗
PubMed2002

Cyclooxygenase-2 mRNA is up-regulated in cirrhotic or chronic hepatitis liver adjacent to hepatocellular carcinoma.

BACKGROUND AND AIM: Hepatocellular carcinoma (HCC) is unique in that its carcinogenesis is related to inflammatory changes and regenerative activities in the background liver. Although there are some data on cyclooxygenase (COX)-2 expression in HCC by immunohistochemical studies, little is known about the possible role of COX-2 in inducing hepatitis and/or carcinoma. To elucidate whether COX-2 is involved in a part of these processes, we attempted to examine COX-2 mRNA both in the adjacent non-tumoral liver and in HCC. METHODS: Twenty-two matched sets of adjacent liver and HCC specimens were analyzed for COX-2 mRNA expression using a real-time quantitative reverse transcription polymerase chain reaction. Cyclooxygenase-2 protein expression was also determined by immunohistochemistry. RESULTS: Cyclooxygenase-2 mRNA expression was significantly higher in the adjacent liver than in HCC (P = 0.016). Cyclooxygenase-2 mRNA expression in adjacent liver tissues was positively correlated with the modified histological activity index scores (r = 0.575, P = 0.006), the serum alanine aminotransferase levels (r = 0.536, P = 0.010), and the Ki-67 labeling indices (r = 0.698, P = 0.001). In contrast, COX-2 mRNA expression in HCC was not correlated with any of the clinicopathological features. CONCLUSIONS: Cyclooxygenase-2 is expressed at higher levels in the adjacent liver than in HCC, and it may be associated with high levels of necroinflammation and regeneration in the background liver. Conversely, COX-2 may have a lesser role in the progression of HCC.

Aged↗
PubMed2002

Treatment of hepatocellular carcinoma with radiofrequency ablation: radiologic-histologic correlation during follow-up periods.

To determine whether radiographic images after radiofrequency (RF)-induced coagulation necrosis are correlated with the pathologic effects, we evaluated the morphology and histologic characteristics of RF ablation lesions over a 6-month follow-up period and compared the results with those of radiologic studies. Thirty-three hepatocellular carcinoma (HCC) tumors with a maximum diameter of 3 cm or less were treated percutaneously by using RF ablation in 26 patients. Six treated tumors were resected 4 weeks after ablation; the remaining 27 treated tumors underwent a biopsy procedure by using an 18-gauge fine needle 3 days, 4 weeks, and 24 weeks after ablation. The excised or biopsied lesions were examined by using histologic methods; the findings were then compared with those of contrast-enhanced computed tomography (CT). Three days after ablation, a core of hypoattenuation surrounded by an enhanced/hemorrhagic rim was observed on the contrast-enhanced CT images. Hematoxylin-eosin-stained specimens were inconclusive as to whether or not cellular viability remained; however, cell viability as determined by the presence of histochemical (lactate-dehydrogenase, maleate-dehydrogenase, and the reduced form of nicotinamide-adenine dinucleotide phosphate [NADPH]-diaphorase) stains was absent, suggesting 100% cellular destruction in the ablated lesion. Four and 24 weeks after ablation, the sizes of the ablated lesions were progressively smaller on the CT images; the histochemical stains remained superior to the hematoxylin-eosin stains for obtaining a definite diagnosis of cell death. We conclude that irreversible cellular destruction, as determined by the absence of positive histochemical staining patterns, was useful for evaluating the pathologic thermal effect of RF ablation. These pathologic findings can be correlated with those of contrast-enhanced CT.

Aged↗
PubMed2002

[A case of AFP-producing gastric cancer with multiple liver metastases responding to CPT-11 and cisplatin combination chemotherapy].

A case of AFP-producing gastric cancer successfully treated with CPT-11 and cisplatin combined therapy is reported together with a review of the literature. A 52-year-old male was admitted with complaints of upper abdominal pain and body weight loss. Gastric cancer with multiple liver metastases was diagnosed based on endoscopy and computed tomography findings. The patient's serum AFP level was 697,100 ng/ml and a biopsy specimen showed AFP-positive tumor cells immunohistochemically. He was treated with a combination chemotherapy consisting of CPT-11 (70 mg/m2) on day 1 and 15, and cisplatin (80 mg/m2) on day 1, repeated every 4 weeks. The primary lesion of the stomach and the liver metastases were remarkably reduced, and the serum level of AFP decreased to 18 ng/ml after 5 cycles of this treatment. No severe side effects were seen during this treatment. This result suggests that combination chemotherapy consisting of CPT-11 and cisplatin may be effective and safe for patients with AFP-producing gastric cancer with multiple liver metastases.

Adenocarcinoma↗
PubMed2002

[Is sentinel lymph node navigation useful for laparoscopic gastrectomy].

The aim of this paper is to assess the usefulness of sentinel lymph node navigation for laparoscopic gastrectomy. The standard lymph node dissection for gastric cancer is a D2 dissection. D2 dissection and sentinel lymph node biopsy can be performed with laparoscopic gastrectomy as well as with open surgery. Sentinel lymph node navigation surgery for gastric cancer has not yet been established, but once a strong consensus is reached we will be able to perform the laparoscopic gastrectomy safely.

Gastrectomy↗
PubMedDate not supplied

The buried bumper syndrome: an early complication of percutaneous endoscopic gastrostomy.

This paper reports on buried bumper syndrome that is an early complication of percutaneous endoscopic gastrostomy. The patient, a 69-year-old woman with impaired conversation due to Alzheimer's disease, was unable to swallow safely. She had undergone percutaneous endoscopic gastrostomy in the standard manner, and it had allowed her to be cared for in her own home. The patient's family had followed the instructions accompanying the device without difficulty until 5 days before presentation, when they noticed leakage around the tube. On examination, the stoma site was reddish, and at endoscopy, we were unable to confirm the internal bumper. Instead, there was a raised mound and a central small round concave area of gastric mucosa without ulceration and edema. Fluid under pressure could not be injected through the percutaneous endoscopic gastrostomy tube. The internal bumper had become embedded in the anterior abdominal wall. In this case, the first percutaneous endoscopic gastrostomy was removed with incision of abdominal wall under local anesthesia for a short period, and a second percutaneous endoscopic gastrostomy was created, without difficulty. Therefore, we should take greater care when we carry out percutaneous endoscopic gastrostomy in patients with dementia and without paralysis of the upper extremities.

Abdominal Wall↗
PubMedDate not supplied

An experimental assessment of suture techniques using Lapra-ty clips through the laparoscope and a case report: laparoscopic closure using Lapra-ty for a perforation of the sigmoid colon.

BACKGROUND/AIMS: As endoscopic procedures become various and complicated, it becomes necessary to develop alternative techniques for tissue suture and ligation. We have developed a new suture technique intracorporeal knotting. METHODOLOGY: An 8-cm suture material having a knot on the other side of a needle, was used in laparoscopic surgery. Furthermore, a 5-mm2 Vicryl mesh was pierced as a buttress. The Lapra-ty was used to secure the tissue. Under laparotomy, the forestomach of a male Donryu rat at 6 weeks of age was incised and sutured with 3-0 Vicryl. 3-0 Vicryl was secured with the knot substitute (group A) or three-throw knot (group B) under Nembutal anesthesia. The animals were sacrificed 7 days after operation. Specimens were taken from the forestomach. Those were fixed with 10% formalin and stained with hematoxylin eosin and Elastica Wangieson methods. The histological findings were compared between group A and group B. A successful laparoscopic closure using Lapra-ty is reported in a patient with a perforation of the sigmoid colon. RESULTS: Microscopically, in this method, neither erosion, ulcer nor microabscess is evidenced. This method may make an intracorporeal knot easy. Also we treated a patient who had a perforation of the sigmoid colon using Lapra-ty. The patient recovered without any trouble. CONCLUSIONS: This method could make ligation technique much easier and the operating time shorter.

Animals↗