Biomedical subjects

S Matsubara

Publications and source records attributed to S Matsubara.

At least 271 records · Page 15Linked to original sources

PubMed1990

A retinoic acid-responsive gene, MK, found in the teratocarcinoma system. Heterogeneity of the transcript and the nature of the translation product.

A newly identified gene, MK, is transiently expressed in the early stages of embryonal carcinoma cell differentiation and in the mid-gestation period of mouse embryogenesis (Kadomatsu, K., Tomomura, M., and Muramatsu, T. (1988) Biochem. Biophys. Res. Commun. 151, 1312-1318). Analysis of various MK cDNA clones revealed differences in the 5'-region. So far three classes of cDNA clones (MK1, MK2, and MK3) have been identified; they were different in the 5'-untranslated region but shared the rest of the sequence. Ribonuclease protection, RNA blotting, and primer extension revealed that MK2-type RNA was the major MK RNA in retinoic acid-treated embryonal carcinoma cells. In addition, the number of A residues in an oligo(A) stretch in the 5'-side of the common sequence differed from 9 to 29. The number was 9 in the most frequent cases, when the putative MK polypeptide had a molecular weight of about 15,500 and had a signal peptide-like sequence. Hybrid selected MK RNA yielded the predicted polypeptide upon in vitro translation. When pancreatic microsomal membranes were included in the translation system, the translation product of MK RNA was processed and entered into the lumen of the membranes. These results suggest that the product of the MK gene is an extracellular polypeptide.

Amino Acid Sequence↗

PubMed1990

Structure of a retinoic acid-responsive gene, MK, which is transiently activated during the differentiation of embryonal carcinoma cells and the mid-gestation period of mouse embryogenesis.

MK is a gene that is expressed temporarily during the early stages of retinoic acid-induced differentiation of embryonal carcinoma (EC) cells and during the mid-gestation period of mouse embryogenesis. The 5'-regions of MK cDNAs and their mRNAs are heterogeneous; so far three kinds of MK cDNAs (MK1, MK2, and MK3) have been isolated. The MK gene was cloned from a genomic DNA library of a BALB/c mouse, and its structure was elucidated. 5'-Region sequences specific for MK1, MK2, and MK3 were arranged in the order of MK3, MK2, and MK1. Then, there was a sequence common to all MK cDNAs consisting of four exons. The results indicate that different species of MK mRNA are generated by the use of alternative promoters and different modes of splicing.

Amino Acid Sequence↗

PubMed1990

cDNA cloning of cytochrome P-450 related to P-450p-2 from the cDNA library of human placenta. Gene structure and expression.

We have isolated and analyzed cDNA (designated P-450HP cDNA) clones from a human placenta cDNA library, using the cDNA for rabbit pulmonary cytochrome P-450p-2, a prostaglandin omega-hydroxylase, as a hybridization probe. The cDNA obtained encoded a polypeptide comprising 511 amino acids with a calculated molecular mass of 58987 Da, and the amino acid sequence similarity with P-450p-2 and rat liver laurate omega-hydroxylase (P-450LA omega) was only about 50%. RNA blot analysis showed that the mRNA hybridizable with the human P-450HP cDNA was inducibly expressed 3-5-fold in rabbit small intestine and lung by gestation, but the expression remained constant in rabbit liver and kidney. This mode of expression was quite different from that of P-450p-2 and P-450LA omega. Interestingly, the mRNA hybridized with the cDNA of P-450HP was found to be expressed in all the human tumor tissues so far examined, in sharp contrast with the facts that almost all the other species of P-450s are known to disappear in the tumor tissues. Taken together, the deduced hemoprotein termed P-450HP dose not seem to be the human counterpart of rabbit P-450p-2 or rat P-450LA omega, and is presumably a new member of the P-450 family including P-450p-2 and P-450LA omega. Furthermore, the corresponding genomic DNA was also cloned and analyzed. The gene of P-450HP spanned 18.8 kb and was separated into 11 exons by 10 introns whose locations were completely different from those of P-450 genes so far determined.

Amino Acid Sequence↗

PubMed1990

Acute toxoplasma myositis: an immunohistochemical and ultrastructural study.

The occurrence is reported of acute myositis in a man with meningoencephalitis due to toxoplasmosis. The ultrastructure and immunohistochemistry of a muscle biopsy of the patient were investigated. Toxoplasma organisms were not found in the muscle biopsy. The perivascular inflammatory cells in the muscle were mainly CD4+ T cells and the inflammatory cells in and around the muscle fibres were chiefly macrophages. Expression of major histocompatibility complex class I and II antigens was observed in the infiltrating cells and endothelial cells of the blood vessels. A small proportion of the infiltrating cells expressed interferon-gamma. A possible role of the immune mechanism in the evolution of myositis is discussed.

Acute Disease↗

PubMed1990

Effects of chronic lithium treatment on serotonin binding sites in rat brain.

The effects of lithium treatment on serotonin (5-HT) binding sites in the rat brain were investigated. Oral administration of lithium carbonate for 3 weeks did not influence 5-HT2 binding sites in the cerebral cortex. On the other hand, the number of 5-HT1 binding sites labeled with [3H]5-HT was decreased significantly in the hippocampus, but not in the cerebral cortex. While non-5-HT1A sites, defined as specific [3H]5-HT binding in the presence of 100 nM 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT), were not affected by lithium treatment in either brain region, chronic lithium administration reduced significantly the density of 5-HT1A sites labeled with [3H]8-OH-DPAT only in the hippocampus, but not in the cerebral cortex. These results suggest that 5-HT1A components are responsible for lithium-induced down-regulation of 5-HT1 binding sites in the hippocampus and that 5-HT1A sites in the hippocampus might be connected with the therapeutic efficacy of lithium.

Animals↗

PubMed1990

Continuous removal of middle molecules by hemofiltration in patients with acute liver failure.

In patients with acute liver failure and hepatic coma, an increase in the abnormal "middle molecules" seen on the chromatograms of the sera is suspected of playing an etiologic role in the coma. A pilot study of continuous hemofiltration using a high-performance membrane was conducted in 16 such patients in an attempt to decrease the serum levels of the middle molecules. The procedure was used alternately with plasma exchange. High-performance liquid chromatography showed a notable removal of the substances in the filtrates and a sequential removal from the serum by hemofiltration. Eight (50%) of the 16 patients had amelioration in level of consciousness and were weaned successfully from hemofiltration. Although only three of the 16 patients survived the acute illness, 13 others lived an average of 15 days and five patients survived greater than 3 wk. While the continuous removal of middle molecules from the serum may not reverse liver failure, this procedure used in conjunction with plasma exchange may provide a means of life support, e.g., for patients awaiting a liver transplant.

Blood Flow Velocity↗

PubMed1990

Protective effect of recombinant human granulocyte colony-stimulating factor (rG-CSF) against various microbial infections in neutropenic mice.

Protective effect of recombinant human granulocyte colony-stimulating factor (rG-CSF) on microbial infections was studied in cyclophosphamide (CPA)-induced neutropenic mice. The neutropenic mice showed severely decreased resistance against systemic infections of Pseudomonas aeruginosa, Escherichia coli, Serratia marcescens, Staphylococcus aureus, and Candida albicans. When such mice were injected subcutaneously with rG-CSF on four consecutive days beginning the day after CPA injection, the decreased anti-microbial resistance of the mice was restored to the level of that in normal mice. The anti-infective effect of rG-CSF was dose-dependent and the 50% effective doses (ED50) in various microbial infections tested were 1-10 micrograms/kg/day. The results suggest that rG-CSF is useful for protection of neutropenic patients from microbial infections.

Animals↗

PubMed1990

Shy-Drager syndrome. Effect of fludrocortisone and L-threo-3,4-dihydroxyphenylserine on the blood pressure and regional cerebral blood flow.

In nine cases of Shy-Drager syndrome, the changes in blood pressure and cerebral blood flow on sitting up from a supine position were studied. The influence of fludrocortisone, a synthetic mineralocorticoid, and L-threo-3,4-dihydroxyphenylserine (DOPS), a precursor of norepinephrine, on these changes was examined. On sitting up, the regional cerebral blood flow (rCBF) measured by Xe133 inhalation showed a tendency to decrease. Fludrocortisone reduced the fall of the mean blood pressure significantly. DOPS reduced the fall of both the diastolic blood pressure and rCBF significantly.

Administration, Oral↗

PubMed1990

Community people's preference of hand drawn face graph as a health informing device.

Although the cartoon of a face is an effective device to visualize the image of numerical indices, its use is not popular among community health personnel. In the present study, we used the face graph as an aid for health informing and educating activities in the setting of a community health activity. For this purpose, we designed a special sheet to draw face by hand. By using this sheet, each person can draw his/her 'face' from one's laboratory data index under the guidance of additional lines. The acceptability of this hand drawn face was evaluated by 283 people aged 65 years and over at a health counseling session. For both men and women, a higher percentage preferred face (37% for men, 40% for women) over numeral (23% for men, 17% for women). The preference for the face graph was also observed at each of three age groups within each sex. The highest affinity to face (64%) was observed for the 14 women who reported as cataract patients.

Aged↗

PubMed1990

Association between mechanical stress and bone remodeling.

Stress patterns and levels were analyzed by use of the three-dimensional finite element method. Three-dimensional models were constructed for the human upper central incisor (1205 nodes and 920 elements) and the sheep metacarpus (240 nodes and 128 elements). Orthodontic and orthopedic forces were applied to the tooth and the bone, simulating orthodontic tooth movement and experimental loading test for the bone. Three principal stresses were determined in the alveolar bone and the sheep long bone. The following results were obtained. 1. Stress distributions in the lateral alveolar bone were similar to those with bone deformation from cantilever bending mode. On the medial surface of the alveolar bone, a bending stress was observed, however, remaining stresses exhibited changes corresponding to those in the PDL produced by tipping displacement of the tooth. 2. In the sheep long bone, tensile and compressive stresses were induced on the dorsal and volar sides, respectively. The magnitude of stresses was greatest at the mid-diaphyseal region. Compressive and tensile stresses were related with bone resorption and apposition. The magnitude of principal stresses was almost proportional to dimensional changes of the bone at the mid-diaphyseal region. Bone remodeling in the long bone is related with mechanical stress, principal stress in particular, indicating that remodeling of the alveolar bone may be induced by application of orthodontic force in addition to conventional change of the bone adjacent to the PDL. Thus, it is shown that mechanical stress in living structures may be a trigger to induce biological remodeling of bones.

Alveolar Process↗

PubMed1990

[An assessment of the acceptance of a face graph as a health education device].

With the aging of society, an increasingly greater number of people receive health evaluations organized by the community. Results of health evaluations are usually obtained as multiphasic numerical figures which are usually written down directly into a prescribed results form by which the community health personnel inform examinees of their health status. Most of aged examinee, however, cannot fully comprehend their own health status expressed as multiphasic numerical figures. Community health personnel also have difficulty in explaining these numerical results. Although the cartoon of face has been shown to be an effective device to help understand multiphasic numerical values, its use is not yet popular among community health personnel. The use of a face graph as an aid for health information and education activities by community health personnel was studied using a simple face drawing system developed for lap-top microcomputers. In this study, the acceptability of this face was evaluated by 29 community health nursing students and 31 community health nurses, studying and/or working in Nagasaki Prefecture, Japan. The first evaluation was made of a newly developed prescribed health evaluation result form using a face graph (facial form). All subjects evaluated the acceptability of this facial form by comparing it to the usual numerical form on the basis of the following five items: (1) discrimination of abnormal range, (2) evaluation of the degree of abnormality, (3) discrimination of normal range, (4) provocation of interest in one's own health status, and (5) stimulation of familiarity in one's own health status.(ABSTRACT TRUNCATED AT 250 WORDS)

Community Health Nursing↗

PubMed1990

[An analysis of health related behavior using interpretive structural modeling].

In order for people to know about and to adopt and maintain healthy living practices, 1) a theoretical overview regarding factors associated with health behavior, and 2) an understanding of the actual pattern of behavior in given situations are needed. While theoretical models are helpful in providing a perspective, these models are not practical enough for understanding actual patterns of behavior. In the present study, the ISM (Interpretive Structural Modeling) method was utilized to understand the actual pattern of health related behaviors. The ISM method is used in systems engineering for structurally modeling complex systems. In this study, the ISM method was applied to grasp the structure of coping behavior in the case of fever caused by a common cold under the following two conditions; i) a simplified situation using eight elementary behaviors, and ii) a more complicated situation using more than eight elementary behaviors. i) Subjects were 30 students of public health nursing. The sequence of eight elementary behaviors was determined by paired comparisons using the ISM matrix. The microcomputer made a network diagram of elementary behaviors. The 30 diagrams, none of which were the same, were classified into three types: 1) simple linear (7 subjects), 2) one junction (12 subjects), 3) two or more junctions (11 subjects). After the experiment, subjects were instructed to evaluate the validity of the ISM method. More than 80 percent of the subjects rated the ISM method as effective in increasing their cognition of the hierarchical structure of health related behaviors. ii) Two subjects (A and B) were instructed to come up with as many possible coping behaviors as they could imagine.(ABSTRACT TRUNCATED AT 250 WORDS)

Health Behavior↗

PubMed1990

[Changes in efficiency of orthodontic tooth movement resulting from differences in bracket materials].

The distance of distal movement of the lower canine was measured, using metal tooth with metal bracket and three types of ceramic bracket (polycrystal alumina x 2, zirconia x 1). Sizes of the wires used in this experiment were 0.018" round, 0.016" x 0.022" and 0.17" x 0.022". The bracket slot and the wire surface employed in the experiment were observed by use of stereoscopic microscope and S.E.M. The following results were obtained. 1. The distance of tooth movement with three types of ceramic bracket was significantly less than that with the metal bracket. 2. Rate of decrease in tooth movement with three types of ceramic bracket ranged from 30% to 60% in comparison with the metal bracket. 3. The wire surface was obviously scratched by the ceramic brackets, whereas slight scratch was observed on the wire with the metal bracket. 4. The distance of tooth movement decreased associated with an increase of wire size. 5. The distance retracted from the cuspal position was less than that from the cervical point. It was shown that efficiency of tooth movement was significantly reduced by the use of ceramic brackets in comparison with the metal bracket. This result seems to be caused by the frictional resistance between the wire and ceramic bracket. It is suggested that refinement of ceramic brackets, slot edge and surface in particular, would produce more efficient and desirable tooth movements in clinical orthodontics.

Ceramics↗

PubMed1990

Chromosome aberration frequencies produced by a 70-MeV proton beam.

The effectiveness of a 70-MeV proton beam in the induction of chromosome aberrations was studied. We employed peripheral lymphocytes and analyzed the frequencies of dicentrics and rings after irradiation at doses ranging from 0.1 to 8.0 Gy at various depths within a Lucite phantom. The frequency of chromosome aberrations after irradiation with an unmodulated proton beam at 5 mm showed a dose-response relationship similar to that of 60Co gamma rays. However, irradiation at greater depths with the spread-out Bragg peak induced higher aberration frequencies at doses lower than those with gamma rays. Furthermore, the distribution curve of chromosome aberration frequencies as a function of depth was found to be slightly different from the physically measured depth-dose curve. With the spread-out Bragg peak the biological effects were more marked at greater depths, resulting in a distribution of relative biological effectiveness values. The results obtained from chromosome aberration analysis may not be related directly to those for the relationship between dose and cell killing. Slight differences in values for relative biological effectiveness due to the change of dose and site of proton beam irradiation may not be important for practical proton beam therapy, but may be important in the prevention of late radiation injuries.

Adult↗

PubMed1990

[Radiotherapy of local regional recurrences of a mastectomized breast carcinoma and its results].

Local-regional recurrences of a breast carcinoma after the mastectomy have been studied. A complete response rate of 89% was noted and this rate was found to decrease with an increase in the size of the mass. The most favorable local control rate was noted in carcinomas of the solitary nodular type where as the worst control late was seen in those with a lymph node metastasis. The 5-year survival rate in all cases was found to be 28.0%, and best in the solitary nodular type carcinomas and worst in carcinomas of the invasive type. Chestwall recurrences associated a local lymph node metastases were found to have a poorer prognosis compared to those without a lymph node metastasis.

Adult↗

PubMed1989

Clozapine: new research on efficacy and mechanism of action.

Clozapine can produce greater clinical improvement in both positive and negative symptoms than typical antipsychotic drugs in neuroleptic-resistant schizophrenic patients. The clinical response may occur rapidly in some patients but is delayed in others. Clozapine has also been reported to produce fewer parkinsonian symptoms, to involve a lower risk of producing tardive dyskinesia, and to produce no serum prolactin elevations in man. It seems likely that these effects are the result of a common biological mechanism or related mechanisms, rather than unrelated effects. Other atypical antipsychotic drugs, such as melperone and fluperlapine, share at least some of these properties. A relatively low affinity for the D-2 dopamine (DA) receptor and high affinity for the 5-HT2 receptor, producing a high 5-HT2/D-2 ratio, best distinguishes atypical antipsychotics like clozapine from typical antipsychotic drugs. Through its weak antagonist action on D-2DA receptors and a potent inhibitory effect on 5-HT2 receptors, as well as its ability to increase DA and 5-HT2 release, clozapine may be able to permit more normal dopaminergic function in the anterior pituitary, the mesostriatal, mesolimbic and mesocortical regions. The numerous advantages of clozapine over typical neuroleptics are consistent with the primary importance of DA to the pathophysiology of schizophrenia. The secondary but still significant role of 5-HT in the action of clozapine may either be direct or via the effect of 5-HT on dopaminergic mechanisms. Some aspects of schizophrenia could be due to a dysregulation of the interaction between serotonergic and dopaminergic neurotransmission.

Antipsychotic Agents↗

PubMed1989

Effect of typical and atypical antipsychotic drugs on 5-HT2 receptor density in rat cerebral cortex.

The effect of acute treatment with seven atypical antipsychotic drugs and four typical antipsychotic drugs on serotonin2 (5-HT2) receptor binding sites in rat cerebral cortex was studied. Among the atypical antipsychotic drugs examined, clozapine, fluperlapine, RMI-81582 and setoperone decreased the density of 5-HT2 receptors, but ticspirone, amperozide and melperone did not. None of the drugs affected the Kd value. Among the typical antipsychotic drugs, loxapine decreased Bmax and increased the Kd of 5-HT2 receptor binding sites, whereas chlorpromazine and cis-flupenthixol had no effect. Clothiapine, a typical antipsychotic drug of the same chemical class as clozapine, decreased Bmax without increasing Kd. The downregulation of 5-HT2 receptor binding sites following a single injection of clozapine, 20 mg/kg, remained almost unchanged during the first 72 hrs and was still significantly decreased for up to 120 hrs. There was no relationship between the affinity for the downregulation of rat cortical 5-HT2 receptor binding site and 5-HT2 receptor density. Coadministration of the D1 dopamine agonist, SKF-38393, did not affect the clozapine-induced downregulation. It is suggested that rapid and prolonged downregulation of 5-HT2 receptor sites is characteristic of some but not all atypical antipsychotic drugs and is not specific to atypical antipsychotic drugs. Dibenzo-epines (clozapine, loxapine, amoxapine, chlothiapine) consistently downregulate 5-HT2 receptors in frontal cortex after acute treatment.

2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-ben↗

PubMed1989

Purification and characterization of hepatic microsomal prostaglandin omega-hydroxylase cytochrome P-450 from pregnant rabbits.

Prostaglandin omega-hydroxylase, designated as cytochrome P-450 LPG omega (P-450 LPG omega), has been purified, to a specific content of 15 nmol of cytochrome P-450/mg of protein, from liver microsomes of pregnant rabbits. The purified P-450 LPG omega was found to be homogeneous on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and to have an apparent molecular weight of 52,000. The enzyme showed a maximum at 450 nm in the carbon monoxide (CO)-difference spectrum for its reduced form. This cytochrome P-450 efficiently catalyzed the omega-hydroxylation of prostaglandin E1 (PGE1), prostaglandin E2 (PGE2), prostaglandin D2 (PGD2), prostaglandin F2 alpha (PGF 2 alpha), prostaglandin A1 (PGA1), and prostaglandin A2 (PGA2), as well as the omega- and (omega-1)-hydroxylation of myristate and palmitate, in a reconstituted system containing cytochrome P-450, NADPH-cytochrome P-450 reductase, phospholipid, and cytochrome b5. Various monovalent and divalent cations further stimulated these reactions in the presence of cytochrome b5. In addition, the reactions were also markedly enhanced by various organic solvents, such as ethanol and acetone. This cytochrome P-450 showed no detectable activity toward several xenobiotics tested. P-450 LPG omega was very similar or identical to the pulmonary prostaglandin omega-hydroxylase (P-450p-2) (Yamamoto, S., Kusunose, E., Ogita, K., Kaku, M., Ichihara, K., & Kusunose, M. (1984) J. Biochem. 96, 593-603) in its molecular weight, absorption spectra, catalytic activity, peptide mapping pattern, and N-terminal amino acid sequence. However, P-450 LPG omega was more unstable than P-450p-2 on storage. In sharp contrast to P-450p-2, P-450 LPG omega was not induced by progesterone.

Alprostadil↗