Search PubMed⌕ Search

Biomedical subjects

Y Takeda

Publications and source records attributed to Y Takeda.

At least 235 records · Page 13Linked to original sources
PubMed2000

Increase in cerebral blood flow as a predictor of hyperbaric oxygen-induced convulsion in artificially ventilated rats.

In spontaneously breathing rats, a transient increase in cerebral blood flow (CBF) has been shown to be a predictor of hyperbaric oxygen (HBO)-induced convulsion. In the present study, we evaluated whether artificially ventilated animals also show an increase in CBF prior to the onset of HBO-induced convulsion. Rats were ventilated with 100% oxygen in 5 atmospheres. CBF, blood pressure, and an electroencephalogram were monitored continuously. Convulsion was observed at 41 +/- 12 min after the initiation of HBO treatment. A single abrupt increase in CBF, reaching 223 +/- 39% of the control level, was observed at 29 +/- 13 min after the initiation of HBO exposure and lasted until the onset of convulsion 12 +/- 2 min later. The time of the increase in CBF correlated strongly with the onset of convulsion (r = 0.99, P < 0.001). Further, the logistic regression curve demonstrated a close relationship between the duration of increased CBF and percentage of epileptiform electrical-discharge incidence (r = 0.92, P < 0.006). The durations of increased CBF causing convulsion in 10%, 50%, and 90% of the rats were 8.4 min, 11.7 min, and 15.1 min, respectively. These results indicate that an increase in CBF is a predictor of HBO-induced convulsion in artificially ventilated rats. The increase in CBF may be involved in the pathogenesis of HBO-induced convulsion.

Animals↗
PubMed2000

Case report of a pigmented dentigerous cyst and a review of the literature on pigmented odontogenic cysts.

This paper reports the first case of a dentigerous cyst containing melanin-pigment and melanocytes in the lining epithelium, and the first case of a odontogenic cyst with macroscopically visible pigmentation in the cyst wall. The patient was a 29-year-old Japanese male with a cystic lesion in the left retromolar area of the mandible. Pathologic examination revealed the lesion to be a dentigerous cyst with or without mild surface keratinization, and numerous granules of melanin-pigment were distributed in the basal cells of the epithelial lining. Furthermore, dendritic melanocytes were scattered in the basal layer. Review of the literature revealed that pigmented odontogenic cysts are uncommon, and only 11 cases have been documented; eight were odontogenic keratocyst, one was a gingival cyst, one was a botryoid odontogenic cyst, and one was a lateral periodontal cyst. The possible origin of melanocytes in odontogenic lesions is discussed.

Adult↗
PubMed2000

Inhibitory tagging in visual search can be found if search stimuli remain visible.

Klein (1988) reported that inhibitory tagging (i.e., inhibition of return in visual search) made reaction times for the detection of small probes increase at locations where there had previously been rejected items in serial visual search. It is reasonable that the attended and rejected locations are inhibited. However, subsequent studies did not support Klein's idea. In these studies, inhibitory tagging was tested after removing the items from the search tasks. The paradigms in these studies were not appropriate for testing an object-based inhibitory effect because the objects (i.e., items) were removed from the display. In the present study, we found that evidence of inhibitory tagging could be observed only when the items of the search tasks were maintained until the responses for the small probes were made. This appeared to be an object-based effect.

Adolescent↗
PubMed2000

Assessment of secondary necrosis of Jurkat cells using a new microscopic system and double staining method with annexin V and propidium iodide.

Using a new system developed by us for acquiring microscopic images automatically, we compared the morphological changes that apoptotic cells undergo with changes in the staining pattern of annexin V-enhanced green fluorescent protein (AV-EGFP) and propidium iodide (PI) in individual cells. Jurkat cells were treated with 5 mM CaCl2 alone, anti-Fas antibody and heating at 42 degrees C for 30 min or 46 degrees C for 60 min, and then were incubated in medium with 5 mM CaCl2. Time-lapse DNA fragmentation analysis and morphological observation revealed that the anti-Fas antibody and heating at 42 degrees C for 30 min induced typical apoptosis in the cells, and heating at 46 degrees C for 60 min induced typical necrosis. Time-lapse observation of individual cells stained with AV-EGFP and PI confirmed that apoptotic cells were stained at first with AV-EGFP alone, and thereafter also with PI when the cellular membrane ruptured and the cell underwent secondary necrosis. Most of the cells which underwent necrosis were stained simultaneously with AV-EGFP and PI. There was a significant time interval between the staining of individual cells with AV-EGFP, indicating apoptosis, and staining of these cells with PI, which indicated the occurrence of secondary necrosis. These results suggest that time-lapse examinations are necessary to distinguish apoptosis, secondary necrosis and necrosis in cells from one another. This study presents direct evidence that apoptotic cells undergo secondary necrosis, which could be recognized with PI.

Annexin A5↗
PubMed2000

Altered expression and function of beta1 integrins in a highly metastatic human lung adenocarcinoma cell line.

In order to investigate the relationship between beta1 integrins and the metastatic ability of cancer cells, we established a novel and highly metastatic cell line designated PC9-f9 from a poorly metastatic human lung adenocarcinoma cell line (PC9) in nude mice. PC9-f9 cells showed higher invasive activity in the Matrigel invasion assay than PC9 cells. Additionally, in cell adhesion assays, PC9-f9 cells adhered to laminin more strongly than PC9 cells and, unlike PC9 cells, adhered to collagen type IV and fibronectin. FACS analysis showed expression of the integrins alpha2beta1, alpha3beta1 and alpha6beta1 on both of the cell lines but alpha4beta1 and alpha5beta1 were neo-expressed on PC9-f9 cells. In cell adhesion inhibition assays, alpha3beta1 was the major laminin receptor for PC9 cells but not for PC9-f9 cells. Alternatively, PC9-f9 cells adhered to collagen type IV via alpha2beta1 and adhered to fibronectin mainly via alpha5beta1 but also moderately via alpha4beta1. The pretreatment of PC9-f9 cells with anti-beta1 monoclonal antibodies suppressed lung metastases by more than 50%. These data suggest that the altered expression and function of beta1 integrins allow PC9-f9 cells to become more adhesive and invasive, and lead to increased metastatic potential.

Adenocarcinoma↗
PubMed2000

Inhibition of gelatinolytic activity in tumor tissues by synthetic matrix metalloproteinase inhibitor: application of film in situ zymography.

Inhibition of gelatinolytic activity in implanted tumor tissues by oral administration of N-biphenyl sulfonyl-phenylalanine hydroxamic acid (BPHA), a selective matrix metalloproteinase (MMP) inhibitor, was demonstrated by means of film in situ zymography (FIZ). Active-MMP-2 but not pro-MMP-2 showed gelatinolytic activity in FIZ, whereas both forms of MMP-2 were found to be active in conventional zymography. A mixture of either tissue inhibitors of metalloproteinase-2 or BPHA with active-MMP-2 resulted in inhibition of gelatinolytic activity in FIZ but not in zymography. Thus, FIZ, but not zymography, could detect net MMP activity in tumor tissues. When a specimen from Ma44 human lung cancer xenograft was subjected to FIZ, gelatinolytic activity was markedly detected with precise localization in the tumor tissues. The gelatinolytic activity detected in Ma44 tumor tissues was found to be mainly derived from MMPs because the gelatin-degrading activity was inhibited by pretreatment of the tumor specimen with MMP inhibitors. Oral administration of BPHA but not (-)BPHA, an enantiomer of BPHA lacking MMP inhibitory activity, successfully inhibited the MMP activity localized in Ma44 tumor tissues in both a dose-dependent and time-dependent manner. The data presented in this report showed for the first time that oral administration of synthetic MMP inhibitor could inhibit the net activity of MMP activity in tumor tissues, suggesting the usefulness of the FIZ technique for determining the effective dose of MMP inhibitor in clinical studies.

Animals↗
PubMed2000

High content of lipid hydroperoxides in livers from patients with chronic hepatitis C.

Hepatic lipid hydroperoxides, which are produced when reactive oxygen intermediates react with polyunsaturated lipids, were measured in patients with chronic hepatitis C. Eight patients with chronic persistent hepatitis (chronic persistent hepatitis group), 16 patients with chronic active hepatitis (chronic active hepatitis group), and 11 patients with cirrhosis (cirrhotic group) were included in the study. Measurements from ten patients without liver disease were used as controls. The lipid hydroperoxide levels in the chronic persistent hepatitis, chronic active hepatitis, and cirrhotic groups were significantly higher than that in the controls (p < 0.05, p < 0.005, and p < 0.005, respectively). Among the patients with chronic hepatitis C, the lipid hydroperoxide levels in the chronic active hepatitis and cirrhotic groups were significantly higher than that in the chronic persistent hepatitis group (p < 0.05 in both groups). The activity and progression of liver disease, represented by the Histology Activity Index, were significantly correlated with the hepatic lipid hydroperoxide level (r = 0.654, p < 0.01). Our findings suggest that an increased hepatic lipid hydroperoxide level is closely related to the activity and progression of chronic hepatitis C.

Adult↗
PubMed2000

[A case of primary macroglobulinemia with acute pulmonary edema].

A 54-year-old man with acute respiratory failure underwent emergency admission to our hospital. Acute pulmonary edema combined with severe pneumonia was strongly suspected, and treatment with diuretics, antibiotics, and corticosteroids was effective. The diagnosis, primary macroglobulinemia, was made from the following findings: a high level of the lgM 1 type monoclonal protein, and an elevated serum viscosity with characteristic "linked sausage effects" seen in the retinal veins. Lymphoplasmacytoid cells, plasma cells, and small lymphocytes were seen in the bone marrow and lymphoplasmacytoid cells were also seen in the smear of the patient's peripheral blood. The types of malignant cells found in his bone marrow were also seen in both infiltrative lesions in the lung parenchyma and the pleural effusion. We concluded that this was a case of primary macroglobulinemia with acute pulmonary edema, which was caused partly by the hyperviscosity syndrome. The antitumor effect of the corticosteroid might have some effect on the recovery from acute respiratory failure and primary macroglobulinemia. He was transferred to the Department of Hematology to receive suitable chemotherapy.

Acute Disease↗
PubMed2000

[Case report--efficacy of short-term intraarterial 5-fluorouracil for liver metastasis from colorectal cancer].

Hepatectomy has the highest cure rate among the various methods for treating liver metastasis from colorectal cancer. We previously reported that continuous hepatic arterial infusion (HAI) of 5-FU is effective for improving the prognosis of patients with liver metastasis. In this study, we examined the efficacy of short-term continuous HAI of 5-FU for treating liver metastasis from colorectal cancer. A 57-year-old woman with a solitary liver metastasis from rectal cancer was treated by continuous HAI of 5-FU (1,000 mg/day) for 6 days. Her elevated serum CEA level (20.7 ng/ml) then returned to normal. Computed tomography revealed a decrease of 55.6% in the size of the liver tumor. Partial segmentectomy (S7) was subsequently performed. Histological examination of the resected tumor showed marked degeneration, necrosis, fibrosis, and calcification with viable moderately differentiated adenocarcinoma cells. These results suggest that preoperative HAI of 5-FU is safe and worth trying in patients with liver metastasis from colorectal cancer.

Adenocarcinoma↗
PubMed2000

[Microwave coagulation therapy for liver recurrence after resection of metastatic colorectal cancer--comparison with re-hepatectomy].

One hundred and fifty-three patients with liver metastases from colorectal cancer underwent hepatectomy from 1979 to 1998. Recurrence in the residual liver occurred in 71 of the 129 patients with curative B resection, and re-hepatectomy has been done in 21 of these 71 patients since 1984. The 5-year survival rate is 37.0%. MCT has been performed in ten of these 71 patients who could not undergo re-hepatectomy and one patient received both therapies. The 3-year survival rate is 66.7%, which is statistically better than that of 35 patients who could not undergo re-hepatectomy before we started MCT (3-year survival rate of 20.0%). Re-hepatectomy is quite effective for recurrent liver remetastasis after hepatectomy, and MCT is probably of similar value.

Colorectal Neoplasms↗
PubMed2000

[Efficacy of combination therapy for multiple liver metastases of colorectal cancer].

In our hospital, combination therapy, mainly intra-arterial infusion, is performed for multiple liver metastases of colorectal cancer. The median survival time of the combination group (n = 18), the hepatectomy only group (n = 3) and the best supportive care group (n = 7) were 21.7, 12.5 and 6.1 months, respectively. The prognosis of the combination group was significantly better than that in the other groups (p < 0.0001). Univariate analysis against the combination group revealed that serum CEA was a significant prognostic factor (p = 0.0196). Moreover, we divided the combination group into two groups on the basis of serum CEA either below or above 50 ng/ml. The prognosis of the low CEA group (n = 11), whose median survival time was 25.9 months, was significantly better than the high CEA group (n = 7), whose median survival time was 17.8 months (p = 0.0031). It therefore appears that combination therapy may be of no benefit when serum CEA is above 50 ng/ml.

Antimetabolites, Antineoplastic↗
PubMed2000

[Two cases of chemotherapy related death associated with acute depression of consciousness complicating hepatic arterial infusion chemotherapy (5-FU and CDDP) for liver metastases from gastric cancer].

Hepatic arterial infusion chemotherapy with 5-FU and CDDP is one of the more attractive regimens for liver metastases from gastric cancer. We report here two chemotherapy related deaths from unexpected complications associated with acute depression of consciousness level due to hepatic arterial infusion chemotherapy.

Acute Disease↗
PubMed2000

Cluster-analysis & patterns of dissemination of multidrug resistance among clinical strains of Vibrio cholerae in Calcutta, India.

BACKGROUND & OBJECTIVES: Antimicrobial resistance among Vibrio cholerae has been monitored for several years in Calcutta. To investigate the changing trends in multidrug resistance (MDR) among different serogroups of V. cholerae and to perform software assisted cluster analysis the current study was undertaken. METHODS: Strains isolated from patients with cholera and "cholera-like" diarrhoea admitted in the Infectious Diseases Hospital, Calcutta were analysed. Eight hundred and forty V. cholerae strains isolated from 1992 through 1997 were tested for susceptibility to 11 antibiotics. Cluster analysis was done using SPSS software. RESULTS: Most of the strains exhibited MDR with fluctuating trends as the resistance profile diverged each year. A total of 119 different resistance profiles exhibited by V. cholerae O1, O139 and non-O1, non-O139 serogroups were analysed by cluster combination method. During 1993 and 1994, 53 per cent of V. cholerae O139 and 82 per cent of V. cholerae O1 serogroups, respectively, exhibited maximal number of new resistance patterns. The frequency of new resistance patterns among V. cholerae non-O1, non-O139 was constantly high (33-47%) during 1995 to 1997. INTERPRETATION & CONCLUSIONS: With a few exceptions, preponderance of the resistance profiles was generally not confined to any serogroup. The cluster analysis depicted dissemination of some of the resistance patterns commonly found among V. cholerae non-O1, non-O139 belonging to different serogroups to the O139 serogroup in the succeeding years. In this study we have shown that the V. cholerae strains are resistant to several antibiotics with constant change in the MDR profiles. It is imperative to define the susceptibility pattern of the strains to determine the effective drug of choice for the treatment of cholera.

Cluster Analysis↗
PubMed2000

[Diagnostic efficacy of 18F-fluorodeoxy glucose-positron emission tomography in multiple solitary pulmonary nodules].

A 73-year-old man was admitted to our hospital for evaluation of abnormal lung shadows in the left lung. Chest computed tomography revealed a cavitary lesion with irregular edges in the right S10 and a nodular lesion with well-defined margins in the left S6. Histological examination of a specimen obtained by transbronchial lung biopsy revealed squamous cell carcinoma in the right S10 but no significant findings in the left S6. Thirdly, 18F-fluorodeoxyglucose-positron emission tomography (18F-FDG-PET) demonstrated that the nodular shadow in the left S6 was a low-uptake structure and that the cavitary lesion in the right S10 was a high-uptake lesion. We therefore considered that the nodular shadow in the left S6 was not one of neoplastic disease. Partial lung resection of the left S6 was carried out by videoassisted thoracoscopic surgery. The pathological diagnosis of the left S6 was epithelial granuloma with caseation. A culture of the same resected specimen was positive for Mycobacterium avium. The eventual clinical staging for the squamous cell carcinoma in the right S10 was cT2N0M0 (IB). Radical surgical treatment and right lower lobectomy were performed for the S10 lesion. We considered that 18F-FDG-PET was an effective noninvasive procedure for diagnosis of solitary or multiple solitary nodular shadows in the lung.

Aged↗
PubMed2000

Pharmacological aspects of ipecac syrup (TJN-119)-induced emesis in ferrets.

In order to elucidate the precise mechanism of ipecac syrup (TJN-119) on the occurrence of vomiting, we examined the effects of ipecac syrup on the abdominal afferent nerve activity as well as on the 5-HT levels of the ileum and area postrema in ferrets. Oral administration of TJN-119 (0.5 mg/kg) produced a significant increase in afferent abdominal vagus nerve activity which lasted approximately 1 hour. The maximum response induced by TJN-119 was estimated to be 219 +/- 18% of the pre-injection level. Cephaeline or emetine, the main alkaloids of ipecac syrup, also demonstrated similar effects on afferent vagus nerve activity. TJN-119 increased the 5-HT content in the ileum but not in the area postrema. These observations illustrate possible mechanisms that may act at peripheral sites. It was recently reported that TJN-119 has a high affinity to 5-HT4 receptors (Hasegawa et al., unpublished data). These results suggest that 5-HT4 receptors may be involved in the emetic action of TJN-119.

Afferent Pathways↗
PubMed1999

Human RNA helicase A is a lupus autoantigen that is cleaved during apoptosis.

Proteolytic cleavage by caspases is the central event in cells undergoing apoptosis. Cleaved proteins are often targeted by autoantibodies, suggesting that the cleavage of self Ags enhances immunogenicity and is prone to induce an autoimmune response. We found autoantibodies that immunoprecipitated a 140-kDa RNA-associated protein, provisionally designated Pa, in 11 of 350 patient sera that were positive for antinuclear Abs in an immunofluorescence test. The Pa protein gave rise to three fragments with m.w. ranging from 120-130 kDa during anti-Fas-activated apoptosis. Pure caspase-3 cleaved the Pa protein into a 130-kDa fragment corresponding to the largest of these three products. Peptide sequence analysis of a tryptic digest from immunoaffinity-purified Pa showed 100% identity to human RNA helicase A (RHA). The identity of Pa with RHA was further confirmed by immunoblotting with rabbit anti-RHA Ab using anti-Pa immunoprecipitates as substrates. All 10 anti-RHA-positive patients who were clinically analyzed were diagnosed as having systemic lupus erythematosus, and 7 of them had lupus nephritis. RHA is a multifunctional protein with roles in cellular RNA synthesis and processing. Inactivation of RHA by cleavage may be an important part of the process leading to programmed cell death. The cleaved RHA fragments that are produced during apoptosis may trigger an autoimmune response in systemic lupus erythematosus.

Amino Acid Sequence↗