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Biomedical subjects

M Takeuchi

Publications and source records attributed to M Takeuchi.

At least 793 records · Page 44Linked to original sources
PubMed1988

Thomsen-Friedenreich antigen in bladder cancer tissues detected by monoclonal antibody.

Monoclonal antibodies against Thomsen-Friedenreich antigen (T-Ag) were obtained by the hybridoma technique. The expression of T-Ag in 73 specimens of bladder cancer was examined by the immunofluorescence method using these monoclonal antibodies. Seventeen (53%) of grade I, 18 (44%) of grade II and 5 (50%) of grade III were diffusely stained with anti-T. Of the T-negative tumors, 14 (44%) of grade I and 13 (32%) of grade II showed positive staining after neuraminidase treatment (cryptic T-positive) while only 1 (10%) of grade III was cryptic T-positive. On the contrary, only 1 case (3%) of grade I was cryptic T-negative while 10 (24%) of grade II and 4 (40%) of grade III (were. The T-antigen expression and the histological grades correlated significantly (p less than 0.05). Twenty-eight (70%) of the T-positive cases and 9 (60%) of the cryptic T-negative cases recurred while only 3 (11%) of the cryptic T-positive cases did (p less than 0.01). The monoclonal antibodies were more useful than peanut lectin (PNA) or conventional polyclonal antibodies on the detection of T-antigen.

Antibodies↗
PubMed1988

Calmodulin antagonists inhibit the phagocytic activity of cultured Kupffer cells.

The mechanism of phagocytosis by Kupffer cells is still unknown. In this study we found that trifluoperazine, chlorpromazine, and W-7, drugs which bind to Ca2+-calmodulin and inhibit its interaction with other proteins, inhibit phagocytosis by cultured Kupffer cells using polystyrene beads, time-lapse VTR systems, and fluorescent staining techniques. Inhibitory effects of these drugs on phagocytosis suggests that the Ca2+-calmodulin system may be involved in this complex cellular function and the integrity of the cytoskeletal system of Kupffer cells is essential to this phenomenon.

Actins↗
PubMed1988

DDAVP and epinephrine-induced changes in the localization of von Willebrand factor antigen in endothelial cells of human oral mucosa.

A peroxidase-labeled antibody technique revealed von Willebrand factor antigen (vWF:Ag) in rough endoplasmic reticulum (rER), the perinuclear region, and the cytoplasmic vesicles of capillary endothelial cells in oral mucosa. After administration of epinephrine or 1-deamino-8-D-arginine vasopressin (DDAVP), the localization of vWF:Ag was shown to have changed to the basement membrane and the surrounding interstitium. This change of vWF:Ag localization induced by epinephrine and DDAVP may play a role in the adhesion of platelets to subendothelium following endothelial injury during surgery and may be an unknown hemostatic effect of these drugs.

Adult↗
PubMed1987

Antitumor activity of 7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxy-camptothec in, a novel water-soluble derivative of camptothecin, against murine tumors.

The search for new water-soluble analogues of camptothecin (CPT) with higher activity and less toxicity has led to the development of a novel compound, 7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxy-camptothecin (CPT-11), which showed significant antitumor activity against a broad spectrum of experimental tumor models by i.p., i.v., or oral administration. When its activity against L1210 was compared with that of CPT and known derivatives, CPT-11 was most effective, giving the highest maximum increase in life span (ILS) and showing good activity over a wide dose range. The antitumor activity of CPT-11 was shown against tumors not only in the ascites form but also in the solid form. Included among the more susceptible murine tumors are S180, Meth A fibrosarcoma, Lewis lung carcinoma, Ehrlich carcinoma, MH134 hepatoma, mammary carcinoma of C3H/HeN mice, L1210, and P388 leukemia. Probable cures of these tumors were induced frequently by CPT-11. The antitumor activity of CPT-11 against i.p.-implanted L1210 was superior to that of Adriamycin in maximum ILS, the number of cured mice, and the therapeutic ratio. CPT-11 at a dose of 100 mg/kg produced an ILS in excess of 300% with five of six mice surviving tumor free, and effected 100% tumor regression at 200 mg/kg, whereas the optimum dose of Adriamycin, 12.5-25 mg/kg, brought about 114-129% ILS with one of six mice surviving. The acute toxicity of CPT-11 was extremely low, particularly in the case of oral administration. CPT-11 is expected to be clinically useful.

Animals↗
PubMed1987

Accessory cell function in a Con A response: role of Ia and interleukin 1.

Accessory cell (A-cell) function in a Con A response was analyzed. Irradiated P388D1 cells efficiently induced a proliferative response to Con A of T cells purified from spleen cells, whereas paraformaldehyde-fixed P388D1 cells failed to serve as A cells. Although IL-1 containing culture supernatant (SN) of a macrophage hybridoma induced the Con A response of the T-cell preparations, the depletion of Ia+ cells by the treatment with anti-Ia antibody and complement abrogated the response in the presence of IL-1. Fixed P388D1 cells and the hybridoma SN synergized in the reconstitution of the response. A 15,000-Da fraction of the hybridoma SN or human recombinant IL-1 alpha was able to substitute the hybridoma SN for the response. The reconstitution of the response by IL-1 and fixed P388D1 cells was inhibited by the addition of monoclonal anti-Ia antibody. These results indicate that IL-1 or fixed P388D1 cell does not exert a sufficient signal by itself and both of them are required for the reconstitution of a Con A response of highly purified T cells, and that Ia on fixed P388D1 cells play an important role.

Animals↗
PubMed1987

Leiomyosarcoma of inferior vena cava.

A case of leiomyosarcoma of the inferior vena cava is presented and pertinent clinical features of 57 reported cases in the English literature are reviewed.

Female↗
PubMed1987

B cells as accessory cells in a Con A response of a T cell clone.

Accessory cell (AC) function of B cells was examined in Con A response of a cloned T cell line, 22-9D, which is Thy 1+,L3T4+,Lyt2-,H-2KbDb+ and I-Ab-.22-9D cells produced IL 2 in the presence of Con A without participation of AC. For the initiation of a proliferative response to Con A, the addition of spleen cells or spleen adherent cells was required. B cells as AC were unable to induce the proliferative response. In the presence of culture supernatant of spleen cells stimulated with Con A (CAS), 22-9D cells showed proliferative response to Con A with B cell AC. The response was inhibited by a relevant monoclonal anti-I-A antibody. Although irradiated spleen cells as AC induced IL 2 receptor expression of 22-9D cells in the presence of Con A, B cells were shown to require the addition of unknown factor(s) in CAS, which was suggested to be different from IL 1, IL 2, IL 3, or IFN-gamma, for the induction of the receptor expression on 22-9D cells.

Animals↗
PubMed1987

Dynamic peripheral nerve metabolic and vascular responses to exsanguination.

We studied the dynamic effects of exsanguination of approximately one-third of rat blood volume over 3-12 min on energy metabolism and blood flow in rat sciatic nerves. Nerve high-energy phosphate compounds were relatively well maintained. There was a modest stimulation of anaerobic metabolism at slow rates of exsanguination, and glucose stores were slightly increased. These findings indicate that when stressed because of significant blood loss, compensatory mechanisms, presumably adrenosympathetic mediated, are effective in vivo. We recorded nerve blood flow (NBF), endoneurial oxygen tension, and mean arterial pressure simultaneously; NBF was linearly related to blood pressure (BP) over a wide range of BPs, confirming that NBF does not significantly autoregulate. Endoneurium underwent oxygen-exchange, indicating that peripheral nerve microvasculature is physiologically nutritive. NBF fell before and at a faster rate than BP, indicating that it is a capacitive system. Nerves also adapted to declining oxygen supplies, presumably by reducing their oxygen consumption. The physiological implications of such a system are discussed.

Anaerobiosis↗
PubMed1987

Antitumor activity of a new camptothecin derivative, SN-22, against various murine tumors.

The antitumor activity of a new camptothecin derivative, SN-22, was evaluated by using various murine tumors. SN-22 showed strong activity against the ascites tumors Ehrlich carcinoma, MM46, CCM, L1210, L5178Y, P388, Meth A, and B16 melanoma. In particular, the maximum increase in life span values for Ehrlich, MM46 and CCM were as high as 253-606% and many mice were cured of these tumors. The effect of SN-22 against solid tumors was also determined. The inhibition ratios were higher than 70% for MM46 and L5178Y. The LD50 of SN-22 in ICR mice was about 1.5 times that of the parent camptothecin.

Animals↗
PubMed1987

Prognostic value and limitation of doughnut pattern of technetium-99m pyrophosphate myocardial uptake in acute anterior infarction.

The prognostic significance of the doughnut pattern of technetium-99m pyrophosphate myocardial uptake was evaluated in 140 patients with acute anterior infarction. There were significantly higher early complications, greater mortality and more severe hemodynamic abnormalities in the doughnut pattern group than in the non-doughnut pattern group. The former had a more depressed left ventricular ejection fraction and larger thallium-201 defect size (27.6 +/- 10.4 versus 40.0 +/- 13.5%, p less than 0.001 and 9.9 +/- 3.6 versus 5.6 +/- 3.3, p less than 0.001, respectively). There was, however, considerable overlap of the ranges of these variables for both groups. The patency rate of the infarct vessel during the acute phase of infarct in each group was similar (54.8 versus 45.2%). It is concluded that the prognostic value of the doughnut pattern may be limited to some extent by this overlapping and the presence of this pattern does not appear to correlate with the lack of residual blood flow to the infarcted area.

Cardiac Catheterization↗
PubMed1987

Effects of percutaneous transluminal coronary angioplasty on segmental left ventricular function in patients with acute myocardial infarction.

In order to investigate the usefulness of percutaneous transluminal coronary angioplasty (PTCA) on subsequent left ventricular (LV) function in patients with acute myocardial infarction (AMI), regional ejection fraction (REF) was calculated from the left ventriculogram and compared in the acute and chronic phases (4 weeks after infarction) in 19 successful cases of PTCA (group A). In addition, 15 successful cases of intracoronary thrombolysis (PTCR) (group R) and 14 unsuccessful cases (group U) were also analyzed in this study. From the results, the following points were elucidated. (1) REF of group A in the chronic phase showed a significant increase compared to that in the acute phase (10 +/- 18% vs 20 +/- 19%, p less than 0.01), and this was similar to that observed in group R (9 +/- 19% vs 21 +/- 16%, p less than 0.01). (2) All cases in group A showed a significant increase in REF (p less than 0.02), if recanalization occurred within 3 hours after the onset of AMI. Some cases in the 3-6 hour recanalization group showed a decrease in REF. (3) In group A, only patients with subtotal occlusion on the initial coronary angiogram showed a significant increase in REF 4 weeks later (p less than 0.01), whereas patients with total occlusion on the initial coronary angiogram showed no significant increase in REF. (4) In group A, only patients recanalized between 3 and 6 hours showed a severe degree of prolonged contrast staining immediately after successful recanalization following PTCA. Thus, chronic phase regional wall motion was markedly improved by PTCA in those cases with residual flow. In contrast, abrupt recanalization after PTCA might causally decrease regional wall motion due to hemorrhagic infarction, if it is performed in cases with total occlusion.

Angioplasty, Balloon↗
PubMed1987

[A case report of multiple endocrine neoplasia type 2b].

A 10-year-old girl was admitted displaying a medullary thyroid carcinoma, accompanying neurinomas of the tongue, marfanoid habitus, megacolon, and scoliosis. Although her adrenal glands were found to be unremarkable on both CT and ultrasonogram examination an MIBG scintiscan showed a 131-1 uptake, suggesting the presence of medullary hyperplasia. Remarkable nodal involvement with invasive features witnessed in the upper mediastinum during tertiary surgery four years later, following a total thyroidectomy. The TCT and CEA profiling was not sufficient enough to predict a recurrence. At the present state there is difficulty in providing an early diagnosis; through node dissection, however, is considered to be necessary at time of primary thyroid operation in cases with MEN type 2b.

Carcinoma↗
PubMed1987

[Myocardial perfusion assessed by dynamic computed tomography before and after percutaneous transluminal coronary angioplasty].

A method for quantitatively and visually assessing myocardial perfusion using a new transmission computed tomography scanner and contrast media injection was devised. Myocardial perfusion was assessed before and after percutaneous transluminal coronary angioplasty (PTCA). Six patients with left anterior descending coronary artery stenosis undergoing PTCA were successfully studied. Dynamic scans, each with a scan time of one sec, were performed at the mid left ventricular level using bolus injections of contrast medium from the inferior vena cava. Regions of interest (ROIs) were located in the left ventricular cavity and in the myocardium perfused by the left anterior descending coronary artery, and gamma-variate fitted time density curves were recorded within the first pass phase, excluding recirculation. Cardiac outputs calculated from the ventricular curves of the ROIs in the left ventricular cavity correlated well with the thermodilution measurements using Swan-Ganz catheters (r = 0.90, p less than 0.01). The ratios of myocardial blood flow (F) to the tissue element volume (V) were calculated (F/V) from the myocardial curves of the ROIs in the myocardium as parameters of myocardial perfusion, according to the Zierler's principle. The F/Vs in the myocardium perfused by the left anterior descending coronary artery before PTCA were significantly less than those of the control subjects (4.4 x 10(-2) +/- 1.2 x 10(-2) vs 8.1 x 10(-2) +/- 2.9 x 10(-2): p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Angina Pectoris↗