Biomedical subjects

M Masuda

Publications and source records attributed to M Masuda.

At least 397 records · Page 22Linked to original sources

PubMed1992

[A case of hemangiopericytoma in the pelvic retroperitoneum].

A case of hemangiopericytoma in the pelvic retroperitoneal space is described. A 54-year-old-male had a retroperitoneal mass which had been incidentally detected during evaluation of microscopic hematuria. The pelvic arteriogram revealed an extremely hypervascular mass at the arterial phase and intensive, longlasting and well-demarcated tumor stain at the capillary phase, which were characteristic of hemangiopericytomas. Resection of the tumor was difficult due to a well developed vessel mesh around the tumor and adhesion to the surrounding tissues. The tumor weighted 45 g. The patient has remained free of disease for 29 months postoperatively. Since histopathological malignant features of hemangiopericytoma are still obscure, long term and close follow up is important.

Hemangiopericytoma↗

PubMed1992

[A case of transitional cell carcinoma of renal pelvis with an extremely high serum carcinoembryonic antigen (CEA) level].

A case of urothelial tumor with extremely high serum carcinoembryonic antigen (CEA) levels is described. A 68-year-old female presented with macroscopic hematuria and left flank pain. Laboratory examination revealed an extremely high serum level of CEA (194 ng/ml) and elevated levels of serum CA 19-9 (235 U/ml) and squamous cell carcinoma (SCC)-Antigen (10.7 ng/ml), while urine CEA remained within normal limits. No abnormal findings were recognized in gastrointestinal and respiratory systems, but left renal pelvic tumor (T4N2M0) was discovered. Nephroureterectomy with regional lymph node dissection was done. The pathologic anatomy was infiltrating non-papillary transitional cell carcinoma (TCC, G2 = G3, pT4N2M0). More than 30% of the tumor cells were positive for CEA by ABC-peroxidase staining. Levels of tumor markers remained higher than normal after the operation and were normalized after M-VAC (methotrexate, vinblastine, adriamycin and cisplatin) chemotherapy. However, 6 months after the operation, levels of tumor markers rose again and lung metastases appeared. She died 10 months after the operation.

Aged↗

PubMed1992

Degradation of myocardial high-energy phosphates during twenty-four hours of cold storage. Effects of cardioplegic versus noncardioplegic arrest.

Purine nucleotide catabolism was examined during 24 hours of cold (0.5 degree C) storage of human transplant recipient hearts, baboon hearts, and dog hearts. The hearts were excised either after cold hyperkalemic cardioplegic arrest or after simple hypothermic arrest (25 degrees C). In human myocardium, hypothermia alone preserved the adenosine triphosphate pool markedly. Even after 24 hours of cold storage, adenosine triphosphate was still 9.5 +/- 2.5 mumol/gm dry weight (58% of the preischemic value). The major fraction of catabolites remained nucleotides: adenosine triphosphate plus adenosine diphosphate plus adenosine monophosphate decreased only from 99% +/- 1% (preischemic value) to 80% +/- 13% of the total purine content. The remaining catabolites were mainly nucleosides (adenosine 0.2% +/- 0.1% and inosine 19% +/- 13% of the total purine content). Cardioplegic arrest before cold storage did not change the pattern of purine nucleotide catabolism in any respect (p greater than 0.05). In baboon myocardium, hypothermia alone preserved the adenosine triphosphate content somewhat less than in human myocardium. Adenosine triphosphate content after 24 hours was 5.2 +/- 1.6 mumol/gm dry weight (40% of the preischemic value). The catabolism of adenosine triphosphate, however, did not proceed far beyond the level of adenosine monophosphate, so that the sum of nucleotides remained the same as in human hearts. Adenosine was 0.2% +/- 0.3% and inosine 17% +/- 4% of the total sum of purines. Also in the baboon heart, cardioplegia did not influence the pattern of catabolism significantly (p greater than 0.05). In the dog myocardium, hypothermia alone did not protect against severe catabolism of adenosine triphosphate. The adenosine triphosphate content at 24 hours of storage was 3.5 +/- 2.5 mumol/g dry weight (25% of the preischemic value). Catabolism of adenosine triphosphate proceeded far beyond the level of the nucleotides (63% +/- 17% of the total sum of purines), resulting in an accumulation of adenosine and inosine (5% +/- 4% and 30% +/- 13% of the total sum of purines) and even of hypoxanthine (1% +/- 1% of the total sum of purines). In the dog heart cardioplegic arrest inhibited adenosine triphosphate catabolism considerably. Adenosine triphosphate content at 24 hours was 8.1 +/- 1.8 mumol/gm dry weight (56% of the preischemic value); 83% +/- 5% of the total purine content remained present as nucleotides, and the nucleoside content was reduced to 2% +/- 3% for adenosine and 11% +/- 6% for inosine.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenine Nucleotides↗

PubMed1992

[A case of dermatomyositis associated with thymic abnormalities].

A case of dermatomyositis (DM) associated with thymic cyst with lymphoid follicle formations has been reported. A 57-year-old man developed polyarthralgia, muscle weakness, heliotrope rash and Gottron's sign. Laboratory findings showed elevated values of creatine-phosphokinase, aldolase and transaminase. He was diagnosed as DM and was treated with prednisolone 50 mg/day. Muscle weakness was improved immediately, although rash persisted unchangeably. He was examined for coexistence of malignant tumor which had been reported frequently as associated with DM. Enlargement of thymus was found by computer tomography and then thymectomy was performed. In his thymus, lymphoid follicle formations, which are as often encountered in other autoimmune diseases, were found. So far, the beneficial effect of thymectomy on the improvement of immunological abnormalities not only in patients with myasthenia gravis but also in patients with other autoimmune diseases has been recognized. In this case, intractable rash in DM improved after thymectomy. Further study needs to clarify the relationships between DM and thymic abnormalities.

Dermatomyositis↗

PubMed1992

[Primary ureteral tumor in the residual ureter: a report of two cases].

Two cases of primary ureteral tumor in the residual ureter are reported. One was in a 40-year-old woman who had undergone simple nephrectomy for renal tuberculosis 6 years earlier. The other was in a 59-year-old man 11 years after ureterostomy for hydronephrosis. They presented with hematuria. Cystoscopic examination revealed a ureteral tumor out of the residual ureteral orifice. Computed tomographic scan showed a perivesical mass attached to the urinary bladder. It is useful for examination of ureteral stump's condition. We performed ureterectomy. The pathological study revealed the former high grade transitional cell carcinoma with squamous cell carcinoma and lymph nodes metastasis and the latter low grade transitional cell carcinoma. They have been free of disease for 5.5 years and 1.75 years, respectively. These cases are the nine and tenth reports of primary ureteral tumor of the ureteral stump in the Japanese literature.

Adult↗

PubMed1992

[Multicenter clinical evaluation of red cell concentrates stored up to 6 weeks in MAP, a new additive solution].

The clinical safety and efficacy of transfusion of red cell concentrates stored in MAP solution (MAP-CRC) containing mannitol, adenine, glucose, phosphate and citrate, into 39 anemic patients were evaluated. In 23 patients, infusion of MAP-CRC was alternated with infusion of ordinary CRC as a control. The MAP-CRC and CRC used in this study were stored at 4 degrees C for an average of 38.2 +/- 2.6 days (n = 52) and 18.1 +/- 2.2 days (n = 26), respectively. Red cell recovery was 77.5% for MAP-CRC and 82.5% for CRC, based on calculation of the increase in hemoglobin level one day after transfusion. There were no differences between patients transfused with MAP-CRC and those transfused with CRC in clinical findings or biochemical data. No major side-effects other than pyrexia associated with the underlying infections were seen in patients transfused with MAP-CRC. MAP-CRC stored up to 42 days is apparently as safe and effective as stored CRC. This new additive solution may therefore be useful for the future expansion of the indications for autologous blood transfusion by facilitating the collection and storage of more blood in the liquid state for a longer period, and may also be useful in obtaining more plasma from whole blood as source plasma.

Adenine↗

PubMed1991

Structural studies on sulfated oligosaccharides derived from the carbohydrate-protein linkage region of chondroitin sulfate proteoglycans of whale cartilage.

From the carbohydrate-protein linkage region of whale cartilage proteoglycans, which bear predominantly chondroitin 4-sulfate, one nonsulfated, two monosulfated and one disulfated hexasaccharide alditols were isolated after exhaustive digestions with Actinase E and chondroitinase ABC, and subsequent beta-elimination. Their structures were analyzed by chondroitinase ACII digestion in conjunction with HPLC and by 500-MHz 1H-NMR spectroscopy. The nonsulfated compound (A) had the following conventional structure: delta GlcA(beta 1-3)-GalNAc(beta 1-4)GlcA(beta 1-3)Gal(beta 1-4)Xylol, where GlcA, delta GlcA and GalNAc are glucuronic acid; 4,5-unsaturated glucuronic acid and 2-deoxy-2-N-acetylamino-D-galactose, respectively. The other compounds were sulfated derivatives of compound A. Two monosulfated compounds (B and C) had an ester sulfate on C4 or C6 of the GalNAc residue, respectively and the disulfated compound (D) had two ester sulfate groups, namely, one on C4 of the GalNAc and the other on C4 of the Gal residue substituted by GlcA. The molar ratio of A/B/C/D was 0.21:0.16:0.36:0.27. The compound containing Gal-4-O-sulfate was previously isolated by us in the form of a sulfated glycoserine [delta GlcA(beta 1-3)GalNAc(4-O- sulfate)(beta 1-4)GlcA(beta 1-3)Gal(4-O-sulfate)(beta 1-3)-Gal(beta 1- 4)Xyl beta 1-O-Ser] from the carbohydrate-protein linkage region of rat chondrosarcoma chondroitin-4-sulfate proteoglycans [Sugahara K., Yamashina, I., DeWaard, P., Van Halbeek, H. & Vliegenthart, J.F.G. (1988) J. Biol. Chem. 263, 10,168-10,174]. The discovery of this structure in the carbohydrate-protein linkage region of chondroitin 4-sulfate proteoglycans from nontumorous cartilage indicates that it is not a tumor-associated product but rather a physiological biosynthetic product since it represents a significant proportion. The biological significance of this structure is discussed in relation to glycosaminoglycan biosynthesis.

Animals↗

PubMed1991

Immunogenicity of human T cell leukemia virus type-I (HTLV-I) antigens for cytotoxic T lymphocytes in the rat system.

We showed previously that WKA (rat MHC, RT-1k) and DA (RT-1a) rat CTL specific for human T cell leukemia virus type-I (HTLV-I) recognized the gag and pX gene-encoded Ag. In the present study, we explored HTLV-I Ag recognized by CTL from other MHC genotype (RT-1l) rats, LEW and F344, and examined whether HTLV-I Ag expressed by recombinant vaccinia viruses (rVV) could prime WKA and LEW rats for HTLV-I-specific CTL. Upon priming in vivo and repetitive stimulation in vitro with HTLV-I+ syngeneic T cells, HTLV-I-specific CD8+ CTL were demonstrated in LEW and F344 rat spleen cell cultures. Interestingly, these CTL were directed against HTLV-I env and pX gene products. Immunization of LEW and WKA rats with the env and gag gene-expressing rVV, respectively, resulted in generation of HTLV-I-specific CD8+ CTL. However, a pX-gene expressing rVV failed to prime either rat strain. In addition, HTLV-I-specific CD8+ CTL from F1 hybrid (WKA x LEW) rats generated by immunization and restimulation with HTLV-I+ syngeneic T cells showed gag and pX Ag specificity on WKA rat cells and env and pX Ag specificity on LEW rat cells. These results suggest that immunogenicity of HTLV-I gag and env Ag in induction of HTLV-I-specific CTL varies depending on MHC, and that the pX Ag expressed by rVV is not a potent immunogen for rats.

Animals↗

PubMed1991

Equivariant algebraic vector bundles over representations of reductive groups: theory.

Let G be a reductive algebraic group and let B be an affine variety with an algebraic action of G. Everything is defined over the field C of complex numbers. Consider the trivial G-vector bundle B x S = S over B where S is a G-module. From the endomorphism ring R of the G-vector bundle S a construction of G-vector bundles over B is given. The bundles constructed this way have the property that when added to S they are isomorphic to F + S for a fixed G-module F. For such a bundle E an invariant rho(E) is defined that lies in a quotient of R. This invariant allows us to distinguish nonisomorphic G-vector bundles. This is applied to the case where B is a G-module and, in that case, an invariant of the underlying equivariant variety is given too. These constructions and invariants are used to produce families of inequivalent G-vector bundles over G-modules and families of inequivalent G actions on affine spaces for some finite and some connected semisimple groups.

Journal Article↗

PubMed1991

Equivariant algebraic vector bundles over representations of reductive groups: applications.

Let G be a connected semisimple Lie group over C. In this paper we construct continuous families of nonisomorphic algebraic G-vector bundles in which the base space is a fixed representation of G. The G-vector bundles constructed are all G-invariant hypersurfaces in a representation of G. We show that in some cases these vector bundles yield continuous families of distinct G-actions on affine spaces.

Journal Article↗

PubMed1991

Phospholipid composition of rat megakaryocytes and its rearrangement in platelets.

Rat platelets and their megakaryocyte precursors were examined for phospholipid composition. (1) The phospholipid composition of rat megakaryocytes, which were enriched and prepared from bone marrow cells, was almost identical to that of platelets. (2) The subclass composition of choline-containing glycerophospholipids (CGP) of rat megakaryocytes differed significantly from that of platelets: 1-alkenyl-2-acyl glycerophosphocholine (GPC) in megakaryocytes accounted for 29% of the total, whereas that in platelets was only 7%. (3) Rat platelets contained a larger amount of arachidonic acid than megakaryocytes, especially in ethanolamine-containing glycerophospholipids (EGP). (4) [32P]Phosphoric acid was significantly incorporated into megakaryocytes, whereas platelets showed little incorporation. On the other hand, the uptake of [3H]arachidonic acid into platelet phospholipids was about 15-times higher than that observed with megakaryocytes. (5) As reported previously for other blood cells, such as neutrophils and macrophages, the radioactivity of labeled arachidonic acid incorporated into CGP of platelets decreased, whereas that incorporated into EGP increased during a subsequent chase period. Hardly any such change was observed with megakaryocytes. These results suggest that the phospholipid composition of rat platelets is mainly determined at the time of thrombopoiesis, whereas the composition of molecular species is remodeled during circulation after thrombopoiesis.

Animals↗

PubMed1991

Increased lysis of patient CD10-positive leukemic cells by T cells coated with anti-CD3 Fab' antibody cross-linked to anti-CD10 Fab' antibody.

An anti-CD3 Fab' x anti-CD10 Fab' bispecific hybrid F(ab')2 antibody (Ab) was generated. This bispecific Ab had a molecular mass of 100 to 110 Kd, and the capacity to react with both CD3+ T cells and CD10+ acute lymphoblastic leukemia (ALL) cells. We studied whether cytotoxic T lymphocytes (CTLs) could lyse patient CD10+ ALL cells after addition of the bispecific Ab. As effector CTLs, interleukin-2 (IL-2)-stimulated peripheral blood mononuclear cells (PBMCs) and CTL clones were used. When IL-2-stimulated PBMCs were assayed for cytotoxicity to 61Cr-labeled CD10+ ALL cells, their activity was shown to be markedly enhanced by the addition of the bispecific Ab. Most of the CTL clones established lacked cytotoxicity for CD10+ ALL cells, but addition of the bispecific Ab induced a significant level of cytotoxicity. CTLs derived from ALL patients also showed significant cytotoxicity for autologous CD10+ ALL cells after addition of the bispecific Ab. However, this Ab did not affect the cytotoxicity of CTLs when CD10- leukemic cells were used as the targets. These findings suggest that the bispecific Ab can be used for immunotherapy in patients with CD10+ ALL.

Antigens, CD↗

PubMed1991

Correlation between the proliferative response to granulocyte colony-stimulating factor and the positivity of transferrin receptor in acute myeloblastic leukemia cells.

The use of granulocyte colony-stimulating factor (G-CSF) after chemotherapy for acute myeloblastic leukemia (AML) has been reported. However, there is a drawback in that G-CSF may stimulate the proliferation of AML progenitors. To determine the parameter(s) indicative of responsiveness of AML blasts to G-CSF, various surface phenotypes of blasts were examined in relation to the blast colony formation stimulated by G-CSF in 39 AML patients. A correlation was found only with transferrin receptor positivity among the various phenotypes studied. The population mean of percentages of transferrin receptor-positive blasts in the group responding to G-CSF in vitro was significantly higher than that of blasts in the group not responding to G-CSF. A further correlation was found between transferrin receptor positivity and the number of G-CSF receptors on the blasts; that is, blasts expressing more G-CSF receptors have greater transferrin receptor positivity. In our previous study, we observed that blasts with a large number of G-CSF receptors produce more colonies in response to G-CSF. These results indicated that blasts expressing more transferrin receptors have a larger number of G-CSF receptors and may show more active proliferation in response to G-CSF. Therefore, the proliferative response of blasts to G-CSF can be predicted by examining transferrin receptor positivity. The clinical use of G-CSF in AML patients may be recommended when the patient's blasts have a low level of transferrin receptor expression. The measurement of transferrin receptors on blasts, instead of the rather complicated G-CSF receptor determination, would be a useful indicator for the safer application of G-CSF in AML patients.

Antigens, CD↗

PubMed1991

A new aspect of coronary artery spasm induced by cardiac surgery.

Five patients developed coronary artery spasm during open heart surgery in our institute between 1984 and 1988. One patient was undergoing coronary artery bypass grafting and the other four valvular surgery or surgery for congenital heart disease. In one of the patients undergoing non-coronary surgery, the preoperative induction of right coronary artery spasm by ergonovine had been documented angiographically while the remaining three patients did not possess organic or functional coronary disease. All five patients exhibited a sudden onset of hemodynamic collapse with ventricular tachyarrhythmias or ST elevation during the early period of reperfusion, the time to onset being 89.2 +/- 84.8 minutes after unclamping of the aorta. In addition, contraction of the right ventricular free wall was severely impaired. Although one patient died due to left ventricular rupture caused by direct cardiac massage, the early mortality thus being 20 per cent, the other four were successfully treated with the intravenous administration of nitroglycerin and diltiazem. Three patients required the assistance of intraaortic balloon pumping for severe cardiac failure. Thus, during open heart surgery, coronary artery spasm can occur even in patients without organic coronary lesions and the possible mechanisms of this condition are discussed herein.

Adult↗

PubMed1991

Cardioprotective effects of nucleoside transport inhibition in rabbit hearts.

The cardioprotective effects of a nucleoside transport inhibitor, R75231, were investigated in the isolated rabbit heart. The hearts were subjected to 20 minutes of global normothermic ischemia followed by reperfusion. Before ischemia either solvent (group 1), 5 mumol/L of adenosine (group 2), or 0.64 mg/L R75231 (group 3) was added to the perfusate. Preischemic hemodynamics were not changed by treatment, except for an increase in coronary flow in the adenosine group (126% of control; p less than 0.05). Upon reperfusion, coronary flow was depressed in the controls (72% of the preischemic control values), increased in the adenosine group (113%) and unchanged in the R75231 group (89%). Functional recovery was significantly better in the adenosine group as well as in the R75231 group as compared with the controls (p less than 0.05). Cardiac output was 74% of the preischemic control value in the R75231 group, 67% in the adenosine group, and only 38% in the controls. Analysis of the coronary effluent after reperfusion showed a significant inhibition of rapid release of purines and a reverse of the adenosine/inosine ratio in the R75231 group as compared with the others. We conclude that R75231 has a cardioprotective effect that is probably related to accumulation of endogenous adenosine.

Adenosine↗

PubMed1991

Clinical study of infertile males with varicocele showing no typical radionuclide blood pooling on dynamic image of scrotal scintigraphy.

A clinical study was done of 19 patients in our male infertility clinic, who were diagnosed as having a varicocele and showed atypical radionuclide accumulation in the dynamic image of scrotal scintigraphy. The semen quality was good in 26 percent and poor in 42 percent. Patients with severe congestion in the varicocele tended to be small in number. The dynamic images of the varicoceles were classified into two groups: one group with no radionuclide accumulation, and one group with patchy radionuclide accumulations. Surgical treatment was performed in patients with poor semen quality or with a long infertility period. Neither improvement in the semen quality nor impregnation was achieved postoperatively in patients who had shown no accumulation of the radionuclide in the dynamic imaging. In patients who had shown patchy radionuclide accumulations, the postoperative results were good. We concluded that preoperative dynamic imaging of scrotal scintigraphy is a good means of estimating the postoperative prognosis of fertility.

Adult↗

PubMed1991

Effects of interleukins 1-7 on the proliferation of T-lineage acute lymphoblastic leukemia cells.

We investigated the proliferative effects of interleukins 1-7 (IL-1 to -7) on leukemic cells from 10 patients with T-lineage acute lymphoblastic leukemia (T-ALL). Five patients had CD7+4-8-acute leukemia, one had CD5+ acute leukemia, and four had CD1+ acute leukemia. To examine the proliferative effect of each interleukin, 3H-TdR incorporation method was used. In the presence of IL-1, no increase in 3H-TdR incorporation was observed for any of the T-ALL cells. With IL-2, 3H-TdR incorporation increased in cells from 5 out of 10 T-ALL patients, including those with CD7+4-8-, CD5+, and CD1+ acute leukemia. In the presence of IL-3 or IL-6, 3H-TdR incorporation increased in cells from 2 out of 5 patients with CD7+4-8- acute leukemia. However, CD5+ or CD1+ acute leukemia cells were not stimulated by IL-3 or IL-6. With IL-4, 3H-TdR incorporation was increased in the cells from 2 out of 5 patients with CD7+4-8- acute leukemia and in the cells of 2 of those with CD1+ acute leukemia. IL-5 increased the 3H-TdR incorporation by cells from 2 out of 5 patients with CD7+4-8- acute leukemia and 1 patient with CD1+ acute leukemia. IL-7 increased 3H-TdR incorporation in cells from all five CD7+4-8- acute leukemia and 2 of those with CD5+ or CD1+ leukemia. No synergistic effect was found when IL-7 and other cytokines were added to cells from the 3 patients with CD7+4-8- acute leukemia who were tested.

Antigens, CD↗

PubMed1991

Antibodies to synthetic platelet-activating factor (1-O-alkyl-2-O-acetyl-sn-glycero-3-phosphocholine) analogues with substituents at the sn-2 position.

We obtained rabbit antibodies by injecting immunogenic conjugates which were prepared by combining covalently 1-O-(15'-carboxypentadecyl)-2-O-acetyl-sn-glycero-3- phosphocholine(acetyl-CPGPC), 1-O-(15'-carboxypentadecyl)-2-O-N,N-dimethylcarbamoyl-sn-glycero-3 - phosphocholine (dimethylcarbamoyl-CPGPC), or 1-O-(15'-carboxypentadecyl)-2-O-N-butyl-carbamoyl-sn-glycero-3-pho sphocholine (butylcarbamoyl-CPGPC) with protein (BSA or KLH), respectively, and examined the specificity of the resulting antibodies by comparison with inhibition of the binding of iodolabeled CPGPC derivatives to the antibodies by corresponding or related phospholipids. Acetyl-CPGPC and dimethylcarbamoyl-CPGPC possessed haptenic activity causing production of antibodies reactive with PAF. Changes of the substituents at sn-2 in the antigens affected the specificity of the resulting antibodies. The affinity of the substituents to the antibodies decreased in the following order: acetyl much greater than dimethylcarbamoyl and butylcarbamoyl for antibodies to acetyl-CPGPC-KLH; dimethylcarbamoyl greater than acetyl much greater than butylcarbamoyl for antibodies to dimethylcarbamoyl-CPGPC-BSA; and butylcarbamoyl greater than dimethylcarbamoyl greater than acetyl for antibodies to butylcarbamoyl-CPGPC-BSA. Naturally occurring phospholipids, including lysoPAF, phosphatidylcholine, lysophosphatidylcholine, and sphingomyelin, revealed no cross-reactivities with these antibodies. Anti-dimethylcarbamoyl-CPGPC-BSA IgG and anti-acetyl-CPGPC-KLH IgG inhibited a PAF-induced aggregation of washed rabbit platelets in a dose-dependent manner. In contrast, anti-butylcarbamoyl-CPGPC-BSA IgG did not affect a PAF-induced platelet aggregation, nor did preimmune IgG.

Animals↗