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H Isobe

Publications and source records attributed to H Isobe.

At least 37 records · Page 2Linked to original sources
PubMed1999

[A giant invasive thymoma made resectable by cisplatin + vincristine + doxorubicin + etoposide (CODE)].

A 39-year-old man experienced cough and dyspnea by right massive pleural effusion. A large tumor was found in the anterior mediastinum and it had invaded the chest wall all around. The diagnosis was invasive thymoma stage IV a by biopsy. His tumor was too large to be resected, so chemotherapy was planned. The tumor responded well to cisplatin + etoposide until day 7, but it relapsed immediately between doses. Hence, we administered cisplatin + vincristine + doxorubicin + etoposide (CODE) with G-CSF for its high-dose intensity. The tumor diminished in size, and the chest wall invasion almost disappeared. An operation was performed. We describe our experience with a case of invasive thymoma which responded to CODE.

Adult↗
PubMed1999

[A clinical application of laser scanning cytometer--the significance in the cytology as an additional diagnostic technique].

Laser scanning cytometer (LSC) is a new machine similar to flow cytometer but with advantages for certain clinical and research applications. LSC is a microscope based and measures cells on a slide with the position of each cell on the slide. This new technique of LSC can be utilized on extremely small specimens and enables direct correlation of all of the measured fluorescent parameters with light microscopic cytologic morphology. To date, LSC has been successfully used to perform DNA content analysis of numerous specimen types and automated analysis of fluorescence in situ hybridization specimens. In this report, we describe characteristics of LSC comparison with flow cytometry and a clinical application of LSC focused on DNA content analysis in clinical specimens with pulmonary disorders. LSC provides a number of benefits that may make it more suitable for clinical laboratories than FCM.

Bronchi↗
PubMed1998

Intracellular accumulation of thallium as a marker of cisplatin cytotoxicity in nonsmall cell lung carcinoma: an application of inductively coupled plasma mass spectrometry.

BACKGROUND: Thallium-201 (201Tl) scintigraphy has been used to detect malignant pulmonary disease. The mechanism of Tl influx in tumor cells is believed to be similar to that of cisplatin (CDDP) mediated by sodium- and potassium-activated adenosine triphosphatase (Na-K ATPase), and the Na-K ATPase activity may determine the cellular CDDP accumulation and sensitivity to CDDP. The objective of this study was to determine the accumulation of CDDP and Tl in vitro by using inductively coupled plasma mass spectrometry (ICP-MS), a new analytic technique for detecting ultra trace elements, and to evaluate the correlations between cellular CDDP and Tl accumulation, between CDDP 50% inhibitory concentration (IC50) values and cellular CDDP accumulation, and between CDDP IC50 values and cellular Tl accumulation. METHODS: Eight nonsmall cell lung carcinoma (NSCLC) cell lines were used (five adenocarcinomas and three squamous cell carcinomas). The cell lines were exposed to CDDP or Tl for 1 hour, and the resulting cellular accumulation of platinum and Tl was determined by ICP-MS. CDDP IC50 values were determined by a soluble tetrazolium/formazan assay. RESULTS: The authors were able to measure cellular CDDP and Tl accumulation precisely, and heterogeneity in the cellular accumulation of CDDP and Tl existed among the NSCLC cell lines. A significant inverse correlation was observed between CDDP IC50 values and the cellular accumulation of both CDDP and Tl. CONCLUSIONS: ICP-MS is suitable for the determination of cellular CDDP and Tl accumulation in NSCLC cell lines. Cellular Tl accumulation determined by ICP-MS may reflect CDDP cytotoxicity rather than cellular CDDP accumulation.

Adenocarcinoma↗
PubMed1998

Surgery for cholecystocholedocholithiasis in a patient with asymptomatic essential thrombocythemia: report of a case.

Essential thrombocythemia (ET) is a myeloproliferative disorder characterized by a remarkable increase in the platelet count and various clinical symptoms. The perioperative management of patients with ET has yet to be determined, especially when there are no clinical symptoms. We report herein the case of a woman with gallstones whose preoperative hematological data showed remarkable thrombocythemia, but her coagulation studies were normal. The Philadelphia chromosome was negative and bone marrow cytology showed a marked increase in megakaryocytes. Surgery was performed under a diagnosis of cholelithiasis with ET. Considering her severe thrombocythemia and obesity, sufficient heparin was administered to prevent deep vein thrombosis; however, this precipitated postoperative bleeding, necessitating a reoperation. A functional abnormality of the patient's platelets was suspected, and the aggregation by adenosine diphosphate was subsequently found to be significantly inhibited. As patients having ET with no symptoms might have depressed platelet aggregability despite remarkable thrombocythemia, when abdominal surgery is performed, prophylactic therapy for deep vein thrombosis should be avoided. Hence, the preoperative aggregation study of platelets might offer useful information about whether postoperative antithrombotic therapy is indicated.

Anticoagulants↗
PubMed1998

Malignant fibrous histiocytoma of the stomach: report of two cases.

Malignant fibrous histiocytoma (MFH) in the stomach is very rare, and only four cases have been reported. As a result, there is still little understanding of its clinical and pathological features. We recently experienced two cases of gastric MFH. The first case was a 78-year-old man with epigastralgia and a loss of body weight. Endoscopy revealed an ulcerated submucosal tumor. A gastrectomy was performed and the diagnosis of MFH was made histopathologically. The second case was a 77-year-old man with pulmonary symptoms. An image diagnosis indicated a strong suspicion of lung cancer, and a right middle and lower lobectomy was thus performed. One month after the operation, a bleeding gastric tumor was found and therefore a gastrectomy was performed. Both tumors were diagnosed as MFH. From the analysis of six reported cases including ours, a preoperative correct diagnosis is found to be difficult although the lesion has grown to a considerable size at the time of operation. Since a metastatic lung lesion was first detected in two out of six cases, it is thus recommended that the stomach should be examined when lung MFH is found. Considering the high mortality and the short survival in the six cases, the prognosis for gastric MFH seems to be poorer than that in the extremities. However, lymph node metastasis is uncommon, and a curative resection is possible in some cases such as in our second case.

Adult↗
PubMed1998

Role of neutrophil elastase in stress-induced gastric mucosal injury in rats.

Activated neutrophils play an important role in tissue injury by releasing various inflammatory mediators capable of damaging endothelial cells. To investigate whether neutrophil elastase (NE) is involved in stress-induced gastric mucosal injury, we examined the effects of 2 NE inhibitors (ONO-5046 and L-658 758) as well as nitrogen mustard-induced leukocytopenia on the formation of gastric mucosal lesions, gastric mucosal blood flow, gastric mucosal microvascular permeability, and gastric neutrophil accumulation in rats subjected to water immersion-restraint stress (WIR). Gastric mucosal injury peaked 8 hours after WIR. Gastric mucosal blood flow, as measured by laser-Doppler flow cytometry, decreased to 45% of its initial level 8 hours after WIR. Gastric mucosal microvascular permeability, evaluated by Evans blue dye leakage to the gastric mucosa, showed an increase, peaking 8 hours after WIR. Gastric accumulation of neutrophils, determined by measuring gastric myeloperoxidase activity and by histologic examination, was also significantly increased 8 hours after WIR. Both of the NE inhibitors markedly prevented the formation of gastric mucosal lesions. They also decreased the reduction in gastric mucosal blood flow seen in animals subjected to WIR while preventing increases in gastric mucosal microvascular permeability. Gastric neutrophil accumulation was significantly reduced in animals given either inhibitor 8 hours after WIR. Leukocytopenia produced effects similar to those produced by the inhibitors. Taken together, these observations strongly suggest that NE promotes stress-induced gastric mucosal injury in rats by reducing gastric mucosal blood flow and increasing neutrophil accumulation.

Animals↗
PubMed1998

Predicting chemotherapeutic response to small-cell lung cancer of platinum compounds by thallium-201 single-photon emission computerized tomography.

Thallium-201 single-photon emission computerized tomography (SPECT) was used to clarify the relationship between 201Tl uptake and the response in chemotherapy to platinum compounds in 21 patients with small-cell lung cancer. 201Tl-SPECT scans were obtained twice: at 15 min (early scan) and 120 min (delayed scan) after an intravenous injection of 111 MBq (3 mCi) of thallium-201 chloride. We obtained the uptake ratio from each scan and calculated the retention index:uptake ratio = region of interest uptake/contralateral normal lung uptake; retention index = (delayed ratio - early ratio)/early ratio. After 201Tl scintigraphy, 12 patients received chemotherapy consisting of platinum compounds and nine were treated with chemoradiation. Among patients receiving only chemotherapy, the retention index correlated with the responses to chemotherapy. In an in vitro study, ouabain, an inhibitor of the Na,K-ATPase pump, reduced sensitivity to cisplatin and inhibited intracellular thallium uptake in the small-cell lung cancer cell line. These studies suggest that 201Tl-SPECT is a useful indicator of response to chemotherapy with platinum compounds in small-cell lung cancer, and that Na,K-ATPase is commonly involved in transporting both thallium and platinum compounds into cancer cells.

Aged↗
PubMed1998

Rapid diagnosis at the outpatient clinic for breast tumors by fine needle aspiration cytology. The utility.

The aim of this study was to emphasize the utility and prove the accuracy of rapid diagnosis at the outpatient clinic for breast tumors by fine needle aspiration cytology [FNAC]. Rapid diagnosis for breast tumors by FNAC is performed on the same day just after mammography and echonography are carried out at our hospital and the result reported to the patients while they are waiting at the outpatient clinic. We evaluated FNAC by rapid diagnosis at the outpatient clinic for 1,786 breast tumors during the last ten years. The cases of no judgement (Class 0) were 11%, negative cases (Class I & II) 72%, suspicious cases (Class III) 7%, and positive cases (Class IV & V) 10%. We experienced only 4 false negative cases and 0 false positive cases among 1,198 cases during the last 5 years, whereas there were 8 false negative cases and 2 false positive cases among 588 cases during the first 5 years. Two false positive cases in the the first 5 years were judged as Class IV, but definitive surgery [mastectomy] was not performed because rapid diagnosis during the operation by frozen section confirmed no malignancy. As a result, all the cases in which mastectomies were performed up to now were confirmed malignant. We emphasize that rapid diagnosis at the outpatient clinic for breast tumors by FNAC is very useful for early detection and treatment and it is very important to consider the histological type of breast tumors by FNAC to prevent misjudgement.

Adult↗
PubMed1998

Bronchogenic cyst with high carbohydrate antigen 19-9 in the cyst fluid and the serum.

A mass of 8 cm in diameter was revealed in the right upper lung field of a 46-year-old female patient. The chest X-ray film taken one year previously revealed only a linear shadow in the same position, which was thought to be a vacant cyst. The levels of carbohydrate antigen (CA) 19-9 in cyst fluid and serum were elevated, at 410,000 and 130 U/ml, respectively. After surgical resection, serum CA19-9 returned to normal. Pathologically, the cyst wall was lined with bronchial epithelium with no evidence of malignancy. Immunohistochemical study revealed CA19-9 positivity in the bronchial epithelium of the cyst wall.

Body Fluids↗
PubMed1998

Rebamipide prevents indomethacin-induced gastric mucosal lesion formation by inhibiting activation of neutrophils in rats.

Since granulocyte elastase has been shown to be involved in the pathogenesis of gastric mucosal lesion formation induced by nonsteroidal antiinflammatory drugs, inhibition of granulocyte elastase release from neutrophils may be useful in the prevention of these lesions. The objective of this study was to determine whether rebamipide inhibits neutrophil activation in vivo and in vitro. Rebamipide and ONO-5046, a specific granulocyte elastase inhibitor, markedly inhibited indomethacin-induced mucosal injury in rats. Gastric myeloperoxidase activity was significantly increased 3 h after indomethacin administration. This increase was significantly inhibited by rebamipide and ONO-5046. Although cimetidine markedly prevented the indomethacin-induced mucosal lesion formation, it did not reduce the gastric myeloperoxidase activity. Rebamipide inhibited granulocyte elastase release from neutrophils in vitro by inhibiting the increase in intracellular Ca2+ level. Cimetidine did not inhibit granulocyte elastase release from neutrophils. Furthermore, the elevation of intracellular Ca2+ level was not inhibited by cimetidine. Therefore, unlike cimetidine, rebamipide may prevent indomethacin-induced mucosal injury by inhibiting neutrophil activation.

Alanine↗
PubMed1997

Ki-67 labeling indices in non-small cell lung cancer: comparison between image cytometry and flow cytometry.

Expression of the proliferation-associated nuclear antigen Ki-67 was studied in 27 human non-small cell lung cancers (NSCLCs). We measured immunohistochemical Ki-67 labeling indices using image cytometry (ICM) and flow cytometry (FCM) and compared the indices determined with the two methods. Ki-67 labeling indices of tumor cells ranged from 2% to 59% with ICM, and from 3% to 56% with FCM, varying from case to case. There was a linear correlation of values between the two methods (r = 0.77, P < 0.05). To examine whether Ki-67 labeling indices represent tumor proliferative activity, we studied the relationship between the Ki-67 labeling index and the S-phase fraction determined by FCM. There was a positive correlation between the Ki-67 labeling index and the S-phase fraction (r = 0.91, P < 0.01). Comparison of Ki-67 labeling indices and clinicopathological parameters showed lower Ki-67 labeling indices in well-differentiated tumors than in moderate and poorly differentiated tumors (P < 0.05). No correlation was observed between Ki-67 labeling indices and p53 expression. It was concluded that the Ki-67 labeling index was in fact measured with both ICM and FCM, and that it represents tumor proliferative activity of NSCLCs.

Adenocarcinoma↗
PubMed1997

Effects of retinoids on the production of tumour necrosis factor-alpha and nitric oxide by lipopolysaccharide-stimulated rat Kupffer cells in vitro: evidence for participation of retinoid X receptor signalling pathway.

Kupffer cells play important roles in the development of liver injury by producing cytokines and free radicals. In consequence inhibition of these inflammatory mediators will be one of the targets for treating liver diseases. Retinoids modulate a wide variety of functions of monocytes/macrophages. Cellular effects of retinoids are mediated by two families of nuclear receptors, retinoic acid receptors (RARs) and retinoid X receptors (RXRs). We examined the effects of several kinds of natural and synthetic retinoids on the production of tumour necrosis factor-alpha (TNF-alpha) and nitric oxide (NO) by LPS-stimulated rat Kupffer cells in vitro. Of the various retinoids tested, 9-cis-retinoic acid (9-cis-RA) and Ro 13-6307 which are agonists of both RARs and RXRs, suppressed the production of TNF-alpha and NO in a concentration-dependent fashion, whereas three types of RAR-selective agonists, Ro 13-7410, Ro 40-6055 and Ro 19-0645 did not show any effect. Furthermore, the RAR alpha antagonist, Ro 41-5253, did not prevent the effects induced by 9-cis-RA. The results suggest that these effects of 9-cis RA and Ro 13-6307 were induced by the RXRs-dependent signalling pathway.

Animals↗
PubMed1997

An effective chemotherapy regimen for liver metastasis from retroperitoneal fibrosarcoma: report of a case.

Retroperitoneal fibrosarcoma is a rare disease that has proven difficult to treat due to its high incidence of postoperative local recurrence. We recently experienced a patient in whom retroperitoneal fibrosarcoma was followed by liver metastasis without local recurrence. A 34-year-old woman who initially presented with right upper quadrant pain was found to have a retroperitoneal tumor by diagnostic imaging techniques. Extirpation of the tumor was performed and the histopathological diagnosis was fibrosarcoma. A solitary metastasis was detected in the lateral segment 1 year after this operation and a lateral segmentectomy was carried out; however, a short time later, multiple liver metastases were found. Initially, ethanol injections were given with little effect, following which CYVADIC chemotherapy, consisting of cyclophosphamide, vincristine, farmorubicin, and dacarbazine was administered. An excellent responsiveness without severe toxicity was achieved after five cycles, with a significant reduction in tumor size, being estimated as a complete response. Thus, we consider that this chemotherapy regimen could be a promising mode of treatment for liver metastasis from retroperitoneal fibrosarcoma without local recurrence.

Adult↗
PubMed1997

Topoisomerase II alpha content and topoisomerase II catalytic activity cannot explain drug sensitivities to topoisomerase II inhibitors in lung cancer cell lines.

PURPOSE: Topoisomerase II alpha content, topoisomerase II catalytic activity and drug sensitivities to the topoisomerase II inhibitors, doxorubicin and etoposide, were examined in a panel of 14 unselected human lung cancer cell lines in order to determine the relationship between topoisomerase II and drug sensitivities to the topoisomerase II inhibitors. METHODS: Drug sensitivities were determined using a microculture tetrazolium assay. The topoisomerase II alpha levels were determined by Western blot analysis and the topoisomerase II catalytic activity was determined using a decatenation assay of kinetoplast DNA, using nuclear protein from cells of each cell line. RESULTS: Drug sensitivity tests revealed that small-cell lung cancer (SCLC) cell lines were more sensitive to drugs than non-small-cell lung cancer (NSCLC) cell lines. The relative topoisomerase II alpha levels and relative topoisomerase II catalytic activity from SCLC cell lines (mean +/- SD 0.89 +/- 0.54 and 5.3 +/- 3.4, respectively) were slightly higher than those from NSCLC cell lines (0.78 +/- 0.56 and 4.0 +/- 2.8, respectively), but the differences were not statistically significant, and not sufficient to account for the variation in drug sensitivities. Moreover, no clear association was observed between the topoisomerase II alpha levels or the topoisomerase II catalytic activity and drug sensitivities in the cell lines studied. CONCLUSIONS: These findings suggest that the difference in drug sensitivities to doxorubicin and etoposide in human lung cancer cell lines might not be explainable by the topoisomerase II alpha levels and topoisomerase II catalytic activity. Moreover, our results suggest that the topoisomerase II alpha levels and topoisomerase II catalytic activity may play a minor role in the determination of clinical drug resistance of human lung cancers.

Adenocarcinoma↗
PubMed1997

Immunohistochemical localization of extracellular matrix components in human breast tumours with special reference to PG-M/versican.

Immunohistochemical localization of the large proteoglycan, PG-M/versican, was studied in 36 breast tumours, including infiltrating ductal carcinomas, benign tumours and fibrocystic diseases. The relation between the proteoglycan and the other extracellular matrix components was also investigated. In the carcinoma tissues, the interstitial elements of the 'specific stroma', consisting of fibroblastic cells and fine fibrils, were reactive to antibody 2B1, which specifically recognizes the large proteoglycan, PG-M/versican. In the peripheral invasive areas of infiltrating ductal carcinoma, the most intense 2B1-positive reaction was visualized in mesenchymal tissues between carcinoma cells clumps and the surrounding tissues, where hyaluronic acid could be demonstrated histochemically. The 2B1-positive elements were not reactive to antibody 6B6, which specifically recognizes small proteoglycan. In the central sclerotic areas, where antibody 6B6 was reactive, a 2B1-positive reaction was detected only in elastosis masses, which also bound antibodies to type IV collagen and laminin, and to some extent antibody raised against chondroitin 6-sulphate proteoglycan. Elastic tissues of blood vessel walls and perivascular elements became reactive to antibody 2B1 when they were involved in carcinoma invasion. The present results have shown that PG-M/versican was localized in the proliferating interstitial tissues, in particular in hyaluronic acid-rich portions, in association with carcinoma cell growth, and also that PG-M/versican accumulated in vascular and perivascular elastic tissues involved in carcinoma invasion. The biological significance of PG-M/versican was briefly discussed.

Breast Neoplasms↗
PubMed1997

All-trans retinoic acid suppresses liver injury induced by Propionibacterium acnes and lipopolysaccharide in rats.

All-trans retinoic acid (ATRA) has been reported to exert major effects on the immune system, including monocytes/macrophages. The present study was designed to determine whether ATRA would modulate macrophage-associated liver injury induced by Propionibacterium acnes and lipopolysaccharide (LPS) in rats. All-trans retinoic acid administration alleviated the liver injury and reduced the incidence of death following hepatic failure. Serum alanine aminotransferase (ALT) levels 5 h after, and survival rates within 12 h after the administration of LPS were significantly lower in the ATRA-treated group (134+/-119 IU/L and 72.7%) compared with the control group (713+/-411 IU/L and 18.2%; P< 0.05). Histological findings supported these results. These effects may be due to suppression of tumour necrosis factor-alpha (TNF-alpha) and superoxide anions produced by activated macrophages. Serum levels of TNF-alpha 1 h after LPS administration were significantly lower in the ATRA-treated group (60.5+/-7.0 ng/mL) as compared with the control group (105.2+/-39.3 ng/mL; P< 0.05). Formazan deposition that was generated by the perfusion of the liver with nitroblue tetrazolium, also suggested suppression of the release of superoxide anions from hepatic macrophages. These results suggest that ATRA acts as an immunomodulator in liver injury by suppressing the activation of liver macrophages.

Animals↗