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Biomedical subjects

M Tajima

Publications and source records attributed to M Tajima.

At least 109 records · Page 6Linked to original sources
PubMed1996

Heterogeneity in the origin and immunophenotypes of "histiocytic" cells in transplantable rat malignant fibrous histiocytoma.

To clarify the origin and nature of "histiocytic" cells in malignant fibrous histiocytoma (MFH), immunoreactivities to rat macrophage/histiocyte-specific monoclonal antibodies (ED1 and ED2) and monocyte chemoattractant protein-1 (MCP-1) production were investigated using rat transplantable MFH-derived cloned cells (undifferentiated MT-8 and fibrohistiocytic MT-9). In different cultures, the positive rates for ED1 and ED2 ranged from 2.5% to 26.0% in MT-8, and from 6.0% to 40.0% in MT-9. In homotransplants, ED1-positive cells were frequently observed in MT-9 tumors, but barely seen in MT-8 tumors. In both MT-8 and MT-9 tumors, ED2-positive cells were not detected within tumors. Immunophenotypic characteristics of MT-8 and MT-9 to these antibodies seemed to be easily altered depending on in vitro and in vivo conditions. By ELISA, MCP-1 was hardly detected in culture supernatants of MT-8 and MT-9, but its level was very high in sera of MT-8- and MT-9-tumor-bearing rats. In rats with these tumors, the number of circulating monocytes was significantly increased and the presence of factors stimulating macrophage proliferation was demonstrated by the colony formation assay using rat bone marrow cells. Histiocytic cells in MT-8 and MT-9 tumors that were produced in nude mice reacted only with antibody to mouse macrophage-associated antigen. This suggests the existence of non-neoplastic, infiltrated macrophages of host origin that were induced probably by MCP-1 and factors stimulating macrophage proliferation. The present studies indicate the presence of heterogeneities in the origin and immunophenotypes of "histiocytic" cells in rat MFH.

Animals↗
PubMed1996

Establishment and characterization of cell lines, MeMS and MeFS, derived from spontaneous rat mesotheliomas.

New cell lines, designated MeMS and MeFS, were established from the epithelial type of mesotheliomas occurring spontaneously in aged male and female Fischer 344 rats, respectively. Morphologically, MeMS and MeFS expressed the epithelial phenotype. Coexpression of keratin and vimentin in both cell lines was confirmed by the immunocytochemistry, one-dimensional gel electrophoresis and immunoblotting for intermediate filament proteins. Hyaluronic acid synthesis of both MeMS and MeFS was demonstrated by the analysis using high-performance liquid chromatography. MeMS and MeFS seem to be useful models for studying the biological nature of rat mesotheliomas.

Aging↗
PubMed1996

Immunomodulatory properties of maxadilan, the vasodilator peptide from sand fly salivary gland extracts.

Sand flies are the arthropod vector of leishmaniasis and salivary gland extracts from these flies exacerbate leishmaniasis in vivo. The mechanism of exacerbation appears to be due to immunomodulatory effects of the saliva on host immune function but the active component is unknown. The following studies reveal that maxadilan, the vasodilatory peptide present in sand fly salivary gland extracts, has immunomodulatory properties. To examine the effect of maxadilan on T cell proliferation, the peptide was added to murine spleen cells stimulated with either concanavalin A or plate-bound anti-T cell receptor antibody. Inhibition of proliferation was noted in a dose-dependent manner for both sets of experiments (P < 0.05). To examine the effect of maxadilan on alloantigen presentation, the peptide was added to mixed lymphocyte and mixed epidermal cell lymphocyte reactions. Inhibition of proliferation was found in these culture systems. Maxadilan also inhibited the delayed-type hypersensitivity reaction in mice (P < 0.05). These observations suggest a role for maxadilan in the pathogenesis of leishmaniasis since the peptide may inhibit the immune response at the site of parasite inoculation, allowing the infection to proceed.

Adjuvants, Immunologic↗
PubMed1996

[Continuous monitoring of blood volume change by measuring hematocrit during cardiopulmonary bypass].

The usefulness of the continuous monitoring system of blood volume change (BV%), by using measured hematocrit, has been evaluated during cardiopulmonary bypass (CPB). Twelve patients for CABG were studied. The optical sensor was incorporated in the venous outlet site of CPB to measure Hct and hemoglobin oxygen saturation. The infusion of the cardioplegia caused a sharp deviation in BV%, and the use of extracorporeal ultrafiltration helped to reduce BV% rapidly. At the end of CPB, BV% was -1.4 +/- 7.7% and showed a good correlation with total water balance during CPB (r = 0.75, P < 0.01). However, the discrepancy between BV% and the positive water balance was observed in a case with LOS. This suggests fluid maldistribution from intra- to extra-vascular space. Continuous BV% monitoring during CPB is useful as an index of water balance and for assessing an optimum blood volume.

Adult↗
PubMed1996

[Intra-operative management during laparotomy for patients under hemodialysis].

We evaluated retrospectively 31 patients under hemodialysis who underwent scheduled laparotomy with a purpose to determine the optimal intra-operative water balance. The patients fell into two different periods according to the difference of the principle of anesthesia. Anesthesia method employed for the former eleven patients (1987.6-1990.12) was NLA with pancuronium for muscle relaxation and they were ventilated mechanically in ICU. More recent twenty patients (1991-1995) had epidural block plus nitrous oxide-oxygen-isoflurane with vecuronium and they were extubated early. These latter patients, compared with the preoperative values, did not show any significant changes in mean arterial pressure or systemic vascular resistance after the operation. Intra-operative water balance showed a positive correlation with PADP (r = 0.57) and a negative correlation with SVR (r = 0.36) at the end of operation. The adequate fluid infusion is necessary to maintain PADP, and the water balance of +3-5 ml x kg-1 x hr-1 is recommended during laparotomy for the patients under hemodialysis.

Anesthesia, General↗
PubMed1996

[Four cases of tuberculous meningitis--clinical significance of pleocytosis with polymorphonuclears as the predominating cell type in CSF].

It has been well known that tuberculous meningitis cases have moderate pleocytosis with mononuclears as predominating cell type in cerebrospinal fluid (CSF). But there are some reports of tuberculous meningitis in which polymorphonuclears was predominant in CSF. In this study, we investigated differential cell counts of CSF in 4 tuberculous meningitis cases. In 3 of the 4 cases, the CSF had a polymorphonuclears preponderance on admission. The elevated ratio of polymorphonuclears seemed to relate with the severity of the disease, and the ratio declined promptly after the initiation of chemotherapy. The 2 cases, which showed extremely high ratio of polymorphonuclears, showed poor prognosis, one died and the other had the severe sequelae such as notable disturbances of consciousness with hydrocephalus. This study suggests that differential cell counts of CSF is a useful measures to predict the prognosis and to follow up patients with tuberculous meningitis. The finding of a polymorphonuclears preponderance in CSF would suggest the severity and activities of the disease and should be considered as an alarm sign in tuberculous meningitis.

Adult↗
PubMed1995

Maxadilan binds to membrane fractions of brain tissue.

Maxadilan is a potent vasodilator peptide isolated from salivary glands extracts of the hematophagous sand fly. Besides effects on the cutaneous vasculature, it has also been shown to relax rabbit aortic rings while elevating levels of cAMP. As a result of the effects on the skin and aorta, it was elected to undertake an examination of the tissue distribution of binding sites for maxadilan. In addition to specific binding in rabbit aorta and spleen, binding was detected in brain from various species including human, bovine, rabbit, rat and mouse with a kD of between 85 and 201 pM. Competitive displacement of [125I] maxadilan by a number of known vasoconstrictor peptides, vasodilator peptides and small molecule receptor ligands did not occur in the rabbit brain preparation. These results suggest the presence of specific binding sites in mammalian tissue for maxadilan whose endogenous ligand remains unknown.

Animals↗
PubMed1995

Malignant lymphoma arising in the duodenum combined with gastric lymphoma and early gastric cancer: a case report.

We report here a 65-year old man with primary duodenal malignant lymphoma combined with gastric lymphoma and early gastric cancer. Malignant lymphoma in the bulbus of the duodenum was suspected of by endoscopic biopsy during follow up of duodenal ulcer. Preoperative examination revealed an extension of malignant lymphoma from the bulbus to the stomach in combination with early gastric cancer. We performed a pancreaticoduodenectomy because the tumor invaded to the second portion of the duodenum. The postoperative course was uneventful and he received adjuvant chemotherapy following surgery. To our knowledge, this case is the first report of primary duodenal malignant lymphoma combined with gastric lymphoma and early gastric cancer.

Adenocarcinoma↗
PubMed1995

Significance of Phe-220 and Gln-221 in the catalytic mechanism of farnesyl diphosphate synthase of Bacillus stearothermophilus.

Farnesyl diphosphate synthase [EC 2.5.1.10] from Bacillus stearothermophilus was specifically altered at two amino acid residues by using site-directed mutagenesis. The highly conserved Phe and Gln residues at the sequential amino acid positions 220-221 in an upstream part of the putative substrate binding site were replaced with Ala and Glu, respectively. These mutageneses (F220A and Q221E) resulted in 10(-5) and 10(-3) decreases in catalytic activity of farnesyl diphosphate synthesis, respectively. Michaelis constants of the Q221E mutant for the allylic substrates (dimethylallyl- and geranyl diphosphates) increased approximately 25- and 2-folds, respectively, compared to wild type, whereas those for the homoallylic substrate (isopentenyl diphosphate) were not altered much. These results suggest that the Phe-Gln motif is involved not only in the binding of allylic substrates but also in the catalysis by farnesyl diphosphate synthase.

Alkyl and Aryl Transferases↗
PubMed1995

Serum from Theileria sergenti-infected cattle accelerates the clearance of bovine erythrocytes in SCID mice.

Anemia is a major clinical sign of Japanese bovine theileriosis caused by Theileria sergenti. To investigate the possible factors causing anemia in cattle, we developed a clearance test for bovine erythrocytes (Bo-RBC) in severe combined immunodeficient (SCID) mice. Clearance of Bo-RBC in the SCID mice was significantly accelerated when the mice were inoculated with a serum sample obtained from an infected calf during a highly parasitized phase but not when they were injected with a serum sample obtained during the convalescence phase. Acceleration of the clearance of Bo-RBC was also observed in mice treated with merozoite extract. Furthermore, the clearance of Bo-RBC that had been treated with merozoite extract was accelerated. A significant hemolytic activity in infected serum (highly parasitized phase) was observed. Activities sufficient to accelerate the clearance of Bo-RBC in SCID mice and to induce in vitro hemolysis of Bo-RBC were also observed with a merozoite extract from T. sergenti. The results suggest a possible linkage between the in vitro hemolysis of Bo-RBC and the acceleration of Bo-RBC clearance in SCID mice.

Acute Disease↗
PubMed1995

Attempt to discriminate between bovine viral-diarrhoea virus strains using polymerase chain reaction.

The polymerase chain reaction (PCR) was applied to detect bovine viral-diarrhoea mucosal-disease virus (BVDV). By the use of properly prepared primers, cytopathogenic NADL, Oregon C24V, Nose, T-20 and KS86-1(+) strains, and non-cytopathogenic New York-1, No. 12, and KS86-1(-) strains could be detected. The PCR system was applied to field isolates of the viruses. All the viruses were detected by the PCR. Four patterns of the PCR amplification were recognized, and it was possible to discriminate between some strains. These results corresponded with the serotype of BVDV, as determined by the serum-neutralizing test. The BVDV gene was detectable from the leucocytes of infected cattle using the PCR method. Moreover, it was possible to detect and discriminate BVDV strains using one PCR tube that included all primer pairs.

Animals↗
PubMed1995

Occurrence of keratoconjunctivitis apparently caused by Mycoplasma gallisepticum in layer chickens.

Natural cases of keratoconjunctivitis, apparently caused by Mycoplasma gallisepticum (MG), in layer chickens are described. The disease occurred in a commercial flock consisting of 36,000 pullets (Babcock), first appearing around 30 days of age. Clinically, affected chickens showed unilateral or bilateral swelling of the facial skin and the eyelids, increased lacrimation, congestion of conjunctival vessels, and respiratory rales. Some of the severely affected chickens closed their eyes. The morbidity reached 27.8%, and it was estimated that approximately 10% died from reduced feed intake due to impaired vision. Ten 70-day-old chickens with clinical diseases were examined for lesions. There was acute to subacute keratoconjunctivitis in all of the chickens, and some exhibited laryngitis. Adherence of mycoplasma organisms to epithelial cells of the conjunctiva, cornea, and larynx was frequently observed. These organisms had an ultrastructure characteristic of MG and showed a positive reaction with rabbit polyclonal antibodies against the S6 strain of MG by immunohistochemical analysis. MG was isolated from tissue homogenates of the eyelids and tracheas of the affected chickens. Many of the chickens had atrophic bursae, and infectious bursal disease virus antigens were detected in necrotic bursal follicles by immunostaining. Therefore, immunosuppression due to infectious bursal disease was implicated in the pathogenesis of keratoconjunctivitis in the present cases.

Animals↗
PubMed1995

Spontaneous diabetes mellitus associated with persistent bovine viral diarrhea (BVD) virus infection in young cattle.

Histologic and immunohistochemical studies were carried out on four young cattle with diabetes mellitus associated with persistent bovine viral diarrhea (BVD) virus infection. Clinical findings included persistent hyperglycemia, decreased glucose tolerance, glycosuria, polydipsia, and severe emaciation. Macroscopically, multiple erosions and ulcers in the mucosa of upper and lower alimentary tracts and swollen lymph nodes were commonly observed. Erosions and ulcers in the mucosa of tongue, esophagus, and forestomach were represented histologically by necrosis of squamous epithelium with neutrophilic infiltration. In the small and large intestines, villous atrophy and suppurative cryptitis were often observed, along with diffuse infiltration of lymphocytes and macrophages and fibroplasia in the lamina propria. In the pancreas of all cattle, there was a reduction in the number of islet cells, and most of the residual islet cells had hydropic degeneration and a decreased number of secretory granules. Immunohistochemical examination confirmed that these cells were severely degranulated beta-cells. In addition, many islets containing necrotic islet cells were observed. These islet cells had increased eosinophilia and shrinkage of cytoplasm, as well as pyknotic nuclei. Inflammation of the islets with mild infiltration of lymphocytes was observed in all pancreatic lobes. In addition, bovine IgG-immunoreactive cells were identified immunohistochemically in the affected pancreatic islets. The BVD virus antigen was not identified in the cytoplasm of the islet cells by immunohistochemical study, although it was identified in the epithelial cells of the small intestine. The histologic and immunohistochemical studies demonstrated that the pancreatic lesions in these animals were similar to those caused by acute insulin-dependent diabetes mellitus (IDDM) in human beings.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Establishment and characterization of a cell line (NB-YK) derived from a transplantable rat nephroblastoma.

A new cell line, designated NB-YK, was established from a transplantable rat nephroblastoma (NB-Y) which was derived from a spontaneous nephroblastoma in an aged Fischer 344 rat. NB-YK grew in a piling-up and noncohesive pattern on the plastic surface and formed colonies in a soft agar. The main cell type of NB-YK represented morphology of mesenchymal phenotype and most of the cells contained several secretory granules in their cytoplasm. Immunocytochemically the cells were positive for vimentin, cytokeratin, and laminin. Coexpression of vimentin and cytokeratin in the cells was confirmed by the one-dimensional gel electrophoresis and immunoblotting for intermediate filament proteins. NB-YK cells were tumorigenic and produced fibrosarcoma-like tumor when inoculated subcutaneously or intraperitoneally into syngeneic rats and nude mice. NB-YK seems to be a useful model for studying biological properties of nephroblastoma.

Animals↗
PubMed1995

A bioassay for bovine interleukin-1 by the A375 cell growth inhibition.

Usefulness of a human melanoma cell line A375 was evaluated for detecting bovine interleukin-1 (IL-1). The A375 cell growth was inhibited by culture supernatant of lipopolysaccharide-stimulated bovine peripheral blood mononuclear cells (LPSsup) in a dose dependent manner. A mixture of anti-human IL-1 alpha and beta antibodies suppressed 60% of this inhibitory activity and was confirmed to bind to about 23 k dalton peptides in the LPSsup by Western blotting. Although serum and bronchoalveolar lavage fluid from a healthy cow showed a low inhibitory activity, those from pneumonic cows showed the higher activities. These activities were also suppressed by anti-human IL-1 antibodies. These findings show the A375 cell growth inhibition assay can be a useful bioassay for bovine IL-1 (like) activity.

Animals↗
PubMed1995

[Invention of a forced-air-ventilated micro-isolation cage and rack system--environment within cages: temperature and ammonia concentration].

There is little information about microenvironments within laboratory animal cages, although several guidelines on the macroenvironment in laboratory animal rooms have been reported. We have developed a forced-air ventilation system (FVMIS) to improve laboratory animal well-being. In this study, we tested the performance of the FVMIS in terms of temperature and ammonia concentration within cages. Continuous measurement of temperature and ammonia concentration was carried out in FVMIS cages housing 5 rats each. The average temperature within the cages was 22 degrees C to 24 degrees C, and the temperature difference among cages was 0.93 degrees C. The air exchange rate used was 65 changes per hour. FVMIS was capable of controlling the temperature within cages uniformly and accurately with a lower air exchange rate than with the conventional system. The ammonia concentration reached 20 ppm within 9 days in a filtercapped conventional cage, but took 13 to 16 days to reach 20 ppm with FVMIS. It appears that FVMIS is capable of suppressing the ammonia concentration increase in cages, thereby reducing the frequency of cage changes and the stress to laboratory animals when cages are changed. In the present study, it was confirmed that FVMIS contributes not only to microenvironmental control in terms of temperature and ammonia concentration with a lower air exchange rate, but also to animal well-being.

Ammonia↗
PubMed1995

[Effect of a combination treatment using imipenem/cilastatin sodium with G-CSF on infections in neutropenic patients with hematological malignancies].

The clinical effectiveness of a combination treatment using imipenem/cilastatin sodium (IPM/CS) with G-CSF was studied in neutropenic patients (< 500/mm3) with hematological malignancies and secondary infections. Thirty seven patients were entered in the trial, and 30 patients were eligible. This combination was effective in 20 patients, thus the overall efficacy rate was 66.7 percent. The combination was effective in all 6 cases with septicemia, in 10 case out of 15 cases with fever after chemotherapy (efficacy rate; 66.7%), in 3 out of 8 cases with respiratory infections including 7 cases with pneumonia (efficacy rate; 37.5%), and a case with laryngopharyngitis. According to the order of the administration, the efficacy rates were 60.0% in 5 cases in whom G-CSF treatment was started before IPM/CS, 66.7% in 21 cases given both G-CSF and IPM/CS simultaneously, and 75.0% in 4 cases in whom IPM/CS was started before G-CSF. The difference was statistically not significant on the efficacy rates in the three groups. The efficacy in 18 cases treated with monotherapy on antibiotic was 72.2% and that in 12 cases treated with IPM/CS in combination with other antibiotics was 58.3%, and the difference in the efficacy rates in these two groups was not statistically significant. According to the neutrophil counts before and after the treatment, high response rate (60.0%) was obtained in cases of severe neutropenia (less than 100/mm3). Bacteriological examinations showed that all of bacteria detected as pathogens (10 strains of Gram-positive bacteria and 6 strains of Gram-negative bacteria) were eradicated, though 3 strains were replaced by other pathogens.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗