Biomedical subjects

T Kaneda

Publications and source records attributed to T Kaneda.

At least 91 records · Page 5Linked to original sources

PubMed1995

Effect of phorbol ester, 12-deoxyphorbol 13-isobutylate (DPB), on muscle tension and cytosolic Ca2+ in rat anococcygeus muscle.

Effects of phorbol ester, 12-deoxyphorbol 13-isobutyrate (DPB), on muscle tension and cytosolic Ca2+ ([Ca2+]i) level was investigated in rat anococcygeus muscle in comparison with other smooth muscles. 1) DPB (10(-6) M) induced a large contraction and an elevation of [Ca2+]i level in rat aorta and small and rhythmic changes in tension and [Ca2+]i level in guinea pig ileum. However, DPB did not change either of the parameters in rat anococcygeus muscle. 2) DPB caused tension development without changing the [Ca2+]i level elevated by high K+, ionomycin or beta-escin in the anococcygeus muscle. 3) In the beta-escin permeabilized muscles of guinea pig ileum and urinary bladder, rabbit mesenteric artery and rat anococcygeus muscle, DPB enhanced the Ca(2+)-developed tension. Moreover, the enhancement was inhibited by H-7 (3 x 10(-5) M). 4) DPB did not cause muscle tension to develop in the muscle of rat aorta, guinea pig ileum and rat anococcygeus muscle, pretreated with phorbol 12-myristate 13-acetate for 24 hr. In conclusion, DPB showed different contractile effects on the aorta, ileum and anococcygeus muscle, respectively. The initiation of muscle tension by DPB probably requires [Ca2+]i and the DPB-induced enhancement may be due to a Ca2+ sensitization of contractile elements in the anococcygeus muscle. Therefore, the difference between the DPB-induced response of the anococcygeus muscle and those of the other muscles seems to be due to a different Ca2+ movement caused by DPB. Moreover, it is suggested that DPB develops muscle tension by increasing [Ca2+]i and enhances it through the mediation of protein kinase C in the anococcygeus muscle as well as the other smooth muscles.

Animals↗

PubMed1995

Effects of phenylephrine on the contractile tension and cytosolic Ca2+ level in rat anococcygeus muscle.

A contractile property of phenylephrine (PE), alpha 1 agonist, on rat anococcygeus muscle was compared with that on rat aorta by simultaneously measuring changes in intracellular Ca2+ ([Ca2+]i) level and muscle tension. (1) PE (0.1-30 microM) and high K+ induced a sustained increases in [Ca2+]i level and muscle tension of both the muscles. (2) An application of verapamil (10 microM) and EGTA (4 mM) decreased the PE- or high K(+)-increased tension and [Ca2+]i level in both the muscle, respectively. (3) A cumulative application of PE or high K+ to anococcygeus muscle and aorta exhibited a positive relationship between [Ca2+]i and developed tension. The developed tension by PE was greater than that by high K+ at the same level of [Ca2+]i only in the aorta. A difference of regression slopes in the relationship between [Ca2+]i level and muscle tension under PE- and high K(+)-treatments in aorta was significant, but that in anococcygeus muscle was not. (4) An application of PE to anococcygeus muscle in Ca2+ free medium elicited a small transient contractile tension and increase in [Ca2+]i level, but that to aorta showed a large and transient increase in both the parameters. (5) Phorbol ester, DPB (1 microM), did not affect muscle tension or [Ca2+]i level in anococcygeus muscle, but DPB induced greater increases in aorta. (6) An application of PE (10 microM) with GTP produced a left shift in the pCa-tension curve in the beta-escin-permeabilized fiber of the anococcygeus muscle. In summary, it is suggested that the sustained contraction induced by PE in anococcygeus muscle is involved with the increases in [Ca2+]i which is due to Ca2+ influx mediated by alpha 1 receptor, but scarcely to Ca2+ release from the intracellular storage, and that an increase in Ca2+ sensitivity to PE is found only in the permeabilized anococcygeus muscle. The Ca(2+)-independent contractile mechanism in PE response as seen in aorta is probably to be absent in anococcygeus muscle. Moreover, it seems that the effect of the drug acting protein kinase C on anococcygeus muscle is extremely lesser than that on aorta.

Adrenergic alpha-Agonists↗

PubMed1995

Evaluation of jawbone calcification in osteopetrotic (op/op) mice using computed tomography.

The study was conducted to evaluate the degree of calcification in the jawbones of 3 pairs of 4-week-old male op/op mice and littermates using computed tomography (CT) numbers. The mean CT numbers for op/op mice (n = 3) were 251.3 HU (range, 226 to 278) in the maxillary bone and 353.7 HU (range, 320 to 398) in the mandibular bone. The mean CT numbers for littermates were 336.7 HU (range, 324 to 350) and 596.6 HU (range, 580 to 604), respectively. The CT numbers of littermates were higher than in op/op mice for both maxillary and mandibular bones. These results indicated that the degree of bony calcification in littermates was higher than that in 4-week-old op/op mice in both the maxillary and mandibular bones. CT is able to demonstrate the degree of bony calcification in the jawbones of op/op mice using CT numbers, and it is suggested that CT is an extremely effective tool for examining the conditions of bone in vivo. This study also shows that op/op mice are useful for investigation of bone calcification or maturation.

Aging↗

PubMed1995

[Intraoperative changes in blood lactate level and body temperature in younger and elderly adults].

Sequential changes in arterial blood lactate concentration and central-peripheral temperature gradient during anesthesia were measured in 10 younger patients (46-63 yr) and 10 elderly patients (66-92 yr) undergoing abdominal surgery. A central temperature probe was attached at the rectum and peripheral probe on the palm of the hand. Anesthesia was induced with thiopental and succinylcholine and maintained with isoflurane and nitrous oxide in oxygen. There was a marked increase in lactate values intraoperatively in the elderly as compared to the younger patients. Difference between central and peripheral temperature increased significantly in the elderly patients, while there was no change in the temperature gradient in the younger patients. Central-peripheral temperature gradient is an indicator of peripheral circulation, and the results imply the presence of anaerobic oxidation in elderly patients during operation. In elderly patients, the functional reserve of organ system and the tolerance to surgical stress are considered to be reduced. Intraoperative elevation of blood lactate levels might be caused either by impairment of peripheral circulation or by metabolic deficit due to age-related decline in hepatic function.

Abdomen↗

PubMed1995

[Effect of amrinone infusion on temperature changes in elderly patients undergoing abdominal surgery].

We evaluated the effect of intravenous infusion of amrinone on the intraoperative changes of temperature. Twenty-six elderly patients scheduled for abdominal surgery were studied. Temperature was monitored at the rectum and the palm of the hand. Fourteen patients in the amrinone group received continuous infusion of amrinone from anesthetic induction until the end of operation, while twelve patients in the control group received the infusion of normal saline. Peripheral temperature was significantly higher in the amrinone group than in the control group. Difference between central and peripheral temperature was significantly smaller in the amrinone group compared to the control group. It is considered that infusion of amrinone is effective to maintain peripheral circulation and to keep the peripheral extremities warm in elderly patients undergoing abdominal surgery.

Abdomen↗

PubMed1995

[Effects of nitrous oxide on electroencephalographic activity during sevoflurane anesthesia: a zero-crossing analysis].

We have investigated the influence of nitrous oxide (N2O) on central nervous system (CNS) during sevoflurane anesthesia by using zero-crossing method of EEG in 31 patients. The study was divided into three parts: Study 1 (n = 18), Study 2 (n = 6) and Study 3 (n = 7). (Study 1) After induction of anesthesia, sevoflurane 1.0 % in oxygen (O2), and sevoflurane 1.0 % with 67 % N2O in O2 were given to the patients sequentially in a random fashion, and EEG was recorded. (Study 2) Sevoflurane 1.7 % in O2, and sevoflurane 0.7 % with 67 % N2O in O2, which were considered to be the same anesthetic depth (= sevoflurane 1 MAC), were inhaled, and EEG was recorded in the same manner as in the study 1. (Study 3) We compared the effects of N2O on EEG during intravenous administration of fentanyl and midazolam with 67 % N2O, and without N2O, and EEG was recorded in the same manner. In all studies, percentage of each frequency range (delta, theta, alpha, beta) and average frequency were calculated by zero-crossing method. During sevoflurane anesthesia, the EEG activity was decelerated with N2O, depending on minimum alveolar concentration (MAC). But there were no significant changes in EEG activity of the patient with and those without N2O during intravenous anesthesia. We concluded that the influences of N2O on CNS can be evaluated by quantitative analysis of EEG.

Adult↗

PubMed1995

[Midterm result of free arterial graft for myocardial revascularization].

Free arterial grafts has been used as grafts for coronary artery bypass grafting (CABG) since April 1993 in our unit and midterm patency was confirmed by coronary angiogram in 32 patients. Of 32 free arterial grafts. 23 right internal thoracic artery grafts (RITAG), 7 gastroepiploic artery grafts (GEAG) and 2 left internal thoracic artery grafts (LITAG) were placed to 38 coronary arteries including 6 grafts for sequential bypass. 20 grafts were placed in the left circumflex artery. 11 to the diagonal branch, 5 to the left anterior descending artery and 3 to the right Free arterial grafts has been used as grafts for coronary artery bypass grafting (CABG) since April 1993 in our unit and midterm patency was confirmed by coronary angiogram in 32 patients. Of 32 free arterial grafts. 23 right internal thoracic artery grafts (RITAG), 7 gastroepiploic artery grafts (GEAG) and 2 left internal thoracic artery grafts (LITAG) were placed to 38 coronary arteries including 6 grafts for sequential bypass. 20 grafts were placed in the left circumflex artery. 11 to the diagonal branch, 5 to the left anterior descending artery and 3 to the right coronary artery. Coronary angiography later than 6 months after operation revealed the patency rate of 100% for LITAG and RITAG and 81.8% for GEAG. In total 36 free arterial graft remained patent and patency rate was 94.7% and the result was comparative to the midterm patency of in situ arterial graft in our series. Free arterial grafts can be expected to offer excellent long term patency and expand the indication of arterial grafts to CABG.

Coronary Angiography↗

PubMed1994

Delay in expression of a mammary tumor provirus is responsible for defective clonal deletion during postnatal period.

A gene-encoding ligand for deletion of T cells bearing TcRV beta 6 and V beta 8.1 cosegregates a new mammary tumor provirus locus, Mtv-50 in NC mice. The sequence of the open reading frame (ORF) in the 3' long terminal repeat (LTR) of Mtv-50 was strikingly similar to those of Mtv-7, Mtv-43 and exogenous mouse mammary tumor virus (SW) with properties of minor lymphocyte stimulating antigen 1a. Consistent with previous reports, clonal deletion of mature thymocytes bearing TcRV beta 6 was defective during the early postnatal period of mice carrying Mtv-50. Appreciable levels of mRNA corresponding to common Mtv ORF and Mtv-6 ORF were expressed in the neonatal thymus, while little, if any, mRNA corresponding to Mtv-50 ORF was detected in the thymus at the early postnatal stage. Delay in expression of Mtv-50 ORF during the postnatal period may be responsible for the failure of clonal deletion of V beta 6-T cells in the early postnatal life of mice carrying Mtv-50.

Amino Acid Sequence↗

PubMed1994

Tissue distribution of ERp61 and association of its increased expression with IgG production in hybridoma cells.

A protein of molecular weight 60 kDa was purified from the culture medium of a murine colon carcinoma cell line, colon26, and its partial amino-acid sequence determined. Extremely high homology was found with the deduced sequence from cDNA of rat ERp61, earlier found to be an endoplasmic reticulum (ER)-resident protein with redox activity and a similar structure to protein disulfide isomerase (PDI). Western blotting analysis showed that colon26 cells secrete a significant amount of ERp61 into culture medium, although most remains intracellular. The thiol:protein disulfide oxidoreductase activity of the purified mouse ERp61 was demonstrated by insulin-reduction assay. The ER location of the protein in fibroblasts was immunocytochemically confirmed by double staining for ERp61 and another ER-resident protein, PDI or Hsp47. Immunohistochemical studies of murine tissues showed a ubiquitous distribution of ERp61 in a wide variety of cell types. However, it was particularly abundant in plasma cells, mucus-secreting cells in various tissues, neuroendocrine cells including neurons, and follicular epithelia of thyroid gland that actively synthesize and secrete proteins containing cysteine residues. Furthermore, a high correlation was observed between intracellular amounts of ERp61 and immunoglobulin production by hybridoma cells. These results indicate that ERp61 may be involved in disulfide bond formation for such proteins.

Amino Acid Sequence↗

PubMed1994

An ultrastructural study of extracellular fibrillar components of developing mouse mandibular condyle with special reference to type VI collagen.

The localization of type VI collagen was examined from birth to 8 weeks of age. Immunohistochemical staining with anti-type VI collagen antibody was strongly positive in the hypertrophic zone and moderately positive in the fibrous zone and the outer periphery of the proliferative zone, but negative in the inner area of the proliferative zone and mature zone. After ATP treatment, type VI collagen periodic fibrils with about 80-nm intervals were frequently observed but only in the fibrous zone. They occurred mainly in the superficial area of this zone, where striated collagen fibrils were sparse, while a few were noted in the inner area, where bundles of collagen fibrils were abundant. From these distributional differences of both components, a subzonation of the fibrous zone into superficial and inner area is suggested. Moreover, with ATP treatment there were fewer type VI collagen periodic fibrils formed with increasing age (8 weeks). Testicular hyaluronidase digestion before ATP treatment facilitated the formation of periodic fibrils, in all the ages examined, in the intercellular space and around the fibroblastic cells. The interaction of type VI collagen with other components such as collagen fibrils, glycosaminoglycans or proteoglycans may play a part in maintaining the structural integrity of extracellular matrix in the mouse mandibular condyle.

Adenosine Triphosphate↗

PubMed1994

Imaging tumors of the minor salivary glands.

Magnetic resonance imaging evaluations of nine histopathologically confirmed minor salivary gland tumors were made retrospectively and compared with evaluations of images obtained by computed tomography. All tumors had low-to-intermediate T1 signal intensities and intermediate-to-high T2 signal intensities. Malignant tumors had an irregular margin in all but one case. Benign tumors invariably had well-defined margins. In terms of tumor margination, the magnetic resonance imaging findings correlated well with the histopathologic findings. Magnetic resonance imaging demonstrated the internal architecture of the minor salivary gland tumors multidirectionally and was superior to computed tomography in this respect and in the ability to locate the tumors.

Adenocarcinoma↗

PubMed1994

Cephalexin concentrations in radicular granuloma following a single oral administration of 250- or 500-mg cephalexin.

1. Cephalexin concentrations in radicular granuloma and serum following a single oral administration of 250- or 500-mg cephalexin were measured by a paper disk method. 2. The highest concentration of cephalexin in radicular granuloma following administration of 250-mg cephalexin to nonfasting patients was observed at 2 hr, and was 1.62 micrograms/g. The mean cephalexin concentration ratio of radicular granuloma/serum at 2 hr was 0.35. 3. The highest concentrations of cephalexin in radicular granuloma following administration of 500-mg cephalexin to nonfasting and fasting patients occurred at 2 and 1.5 hr, and was 3.35 and 3.42 micrograms/g, respectively. Mean cephalexin concentration ratios of radicular granuloma/serum at 2 and 1.5 hr were 0.32 and 0.30, respectively. 4. All mean cephalexin concentrations in radicular granuloma following administration of 500-mg cephalexin to both fasting and nonfasting patients exceeded MIC for 90% (2 micrograms/ml) of clinically isolated strains of alpha-hemolytic streptococci. However, those concentrations obtained by 250-mg cephalexin did not exceed it.

Adult↗

PubMed1994

Intercellular adhesion molecule-1 and leukocyte function-associated antigen-1 are involved in protection mediated by CD3+TCR alpha beta- T cells at the early stage after infection with Listeria monocytogenes in rats.

To investigate the significance of intercellular adhesion molecule-1 (ICAM-1) and leukocyte function-associated antigen-1 (LFA-1) in host defense against infection with intracellular parasites, we examined the effects of in vivo pretreatment with mAbs to ICAM-1 (1A29) and LFA-1 alpha (WT-1) on the protection against infection with Listeria monocytogenes in Fisher F344/N rats. Expression of ICAM-1 and LFA-1 alpha molecules on T cells in spleen, liver and peritoneal cavity of rats was down-regulated after i.p. administration with daily doses of 300 micrograms of either 1A29 or WT-1 for 10 days. The survival rate of rats inoculated with viable Listeria was significantly reduced by in vivo pretreatment with 1A29 together with WT-1 for 10 days but not by in vivo pretreatment with control mAb. The numbers of bacteria in the spleen in rats pretreated with both 1A29 and WT-1 were significantly increased on day 3 and day 6 after infection with 1 x 10(7) of viable Listeria corresponding to 1/30 of LD50 to normal rats. Thus, the resistance against listerial infection was severely impaired by combinational pretreatment with mAbs in ICAM-1 and LFA-1 alpha. As shown in our previous report, the early appearance of CD3+TCR alpha beta- T cells, presumably TCR gamma delta T cells, was evident in the peritoneal cavity and liver of control rats at the early stage after listerial infection, while this was suppressed at this stage in rats pretreated with both 1A29 and WT1.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1994

Lidocaine hydrochloride and acetylsalicylate kill bacteria by disrupting the bacterial membrane potential in different ways.

Lidocaine hydrochloride (LH), a local anesthetic, and acetylsalicylate (AcSAL), show antibacterial activity for both gram-negative and gram-positive bacteria. Kinetic studies indicated that antibacterial activity of LH was different from that of AcSAL. A subinhibitory concentration of LH and AcSAL enhanced the sensitivity of Escherichia coli, Salmonella typhimurium, and Pseudomonas aeruginosa to novobiocin and nalidixic acid. The synergistic effect of AcSAL with novobiocin and nalidixic acid was higher than that of LH. The effect of both drugs on the membrane potential of inner membrane was also studied using inverted membrane vesicles of bacteria. Both LH and AcSAL depolarized the membrane potential after the vesicles were energized with nicotinamide adenine dinucleotide. However, unlike AcSAL, pre-treatment of vesicles with LH had no effect on the generation of membrane potential. These results suggest that depolarization of the cytoplasmic membrane, preceded by the permeabilization of the outer membrane for gram-negative bacteria, is associated with antibacterial activity of LH and AcSAL. The difference in actions of LH and AcSAL was discussed.

Anti-Bacterial Agents↗

PubMed1994

Flow cytometric detection of proliferative cells in leukemias.

We studied the proliferative activity of leukemic cells obtained from the peripheral blood and bone marrow of 34 patients; 30 with acute leukemia and 4 with chronic myelogenous leukemia in blastic crisis. Flow cytometry was performed using monoclonal antibody against DNA polymerase alpha. Since fresh and frozen cells showed virtually identical DNA polymerase alpha-positive populations and flow cytometric histograms, 52 cryopreserved samples (25 from peripheral blood and 27 from bone marrow) were used in this study. The DNA polymerase alpha-positive population ranged from 20.4% to 84.7% in peripheral blood, and from 6.5% to 92.1% in bone marrow. A positive correlation (r = 0.76, P < 0.01) was found between DNA polymerase alpha-positive populations in peripheral blood and bone marrow from the same patient. This suggests that the DNA polymerase alpha-positive population in the bone marrow can be estimated from that in peripheral blood. No relationship was observed between the positive population and the response to chemotherapy. Statistical analyses for all cases showed no relationship between the DNA polymerase alpha-positive population and either the tumor cell count or time to reach a nadir. However, a negative correlation was observed between the positive population in bone marrow samples and the time to reach a nadir (r = -0.64, P < 0.05) in those patients who achieved a complete response. In addition, in the cases of acute non-lymphocytic leukemia who did not respond to chemotherapy, a positive correlation was observed between the tumor cell count in bone marrow and the DNA polymerase alpha-positive population (r = 0.93, P < 0.01). Thus, the method described here provides a simple and time-efficient means of detecting the proliferative activity of leukemic cells, which is a useful parameter in the treatment of leukemia.

Adolescent↗

PubMed1994

Development and characterization of chimeric anti-carcinoembryonic antigen monoclonal antibodies and their Fab fragments.

In an attempt to reduce the immunogenicity of two different murine anti-carcinoembryonic antigen (CEA) monoclonal antibodies (MAbs), KM10 and A10, we produced recombinant mouse/human chimeric MAbs and the respective Fab fragments carrying the variable regions of the murine MAbs. Chimeric A10 Fab fragment was expressed in Escherichia coli, and produced in large quantities in a mini-jar fermentation system. In competitive binding assays, chimeric MAbs and their Fab fragments showed identical specificity to human CEA epitopes, as compared to the parental MAbs or Fab fragments. Both chimeric Fab fragments exhibited strong immunohistochemical reactivity with various gastrointestinal carcinomas and no reactivity with CEA-related antigens, such as NCA (nonspecific cross-reacting antigen) or BGPI (biliary glycoprotein I). Furthermore, chimeric KM10 MAb elicited substantially higher antibody-dependent cellular cytotoxicity than the murine MAb. Complement-dependent cytotoxicity in vitro was much weaker with chimeric KM10 MAb. These results indicate that chimeric MAbs or Fab fragments could potentially replace the parental murine antibodies or their Fab fragments in therapy or diagnosis of human gastrointestinal carcinomas.

Animals↗

PubMed1994

Bactericidal action of tachyplesin I against oral streptococci.

Tachyplesin I, a polycationic antimicrobial peptide isolated from hemocytes of horseshoe crabs, kills bacteria by disrupting the membrane potential of the cytoplasmic membrane. The present study shows that, among 36 oral streptococcal strains, 12 of 21 Streptococcus sanguis, 3 Streptococcus mutans, 9 Streptococcus salivarius and 3 Streptococcus milleri strains were susceptible to tachyplesin I, whereas 9 S. sanguis strains were resistant. Interestingly, these resistant strains include the clinical isolates from both Kawasaki disease and Behçet patients. According to the time-kill study, tachyplesin I inhibited irreversibly the growth of S. sanguis, S. mutans and S. salivarius strains within 20 min and an S. milleri strain within 80 min. Although it has been suggested that Escherichia coli cultured in rich media were more susceptible to tachyplesin I, the present results show that only 3 S. milleri strains were more sensitized to tachyplesin I in a glucose-supplemented medium, and other tested strains were not. Similarly, only 4 strains were more resistant to tachyplesin I in saline than these were in a rich medium.

Anti-Bacterial Agents↗

PubMed1994

[Application of whole layer core biopsy of bladder wall to paravesical tumor].

We have reported the usefulness of percutaneous or transurethral whole layer core biopsy (WLCB) of bladder wall for staging of invasive bladder cancer. We have applied WLCB to 3 cases of paravesical tumor with good results. The first case was in a 3-year-old boy suspected of retrovesical sarcoma. Percutaneous WLCB revealed an inflammatory tumor of the Douglas cavity which was probably caused by perforation of appendix. The tumor disappeared by antibiotics alone. The second case was in a 37-year-old female with retrovesical tumor suspected to be ovarial cancer because of the high value of CA19-9 and CA125. Transurethral WLCB showed invasion of endometriosis to bladder muscle layer. The third case was in a 75-year-old female diagnosed by transurethral WLCB as sigmoid colon cancer invading until the deep bladder muscle layer. Cold cup punch biopsy was not informative in these 3 cases. Percutaneous or transurethral WLCB is safe and easy to perform, and is a technique recommended for diagnosis of pathology and bladder invasion of paravesical tumor.

Adult↗