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Biomedical subjects

T Mitsui

Publications and source records attributed to T Mitsui.

At least 325 records · Page 18Linked to original sources

Two-dimensional echocardiographic evaluation of the severity of mitral stenosis with reference to the prediction for mitral valve commissurotomy or replacement.

Thirty patients with mitral stenosis were classified into three grades of severity reflected by anterior mitral leaflet and subvalvular apparatus using two-dimensional echocardiography in order to study the possibility of predicting the type of surgery indicated, and were evaluated pre- and postoperatively for systolic and diastolic volumes; left heart function using left ventricular posterior wall movement (LVPWVSmax, LVPWVdmax) and posterior wall excursion (PWE) and newly devised left atrial empty volume ratio (LAEVR). The LVPWVSmax was increased from 57 +/- 7 to 74 +/- 7 mm/s (p less than 0.001) in grade I, from 48 +/- 13 to 63 +/- 9 mm/s (p less than 0.02) in grade II, and from 44 +/- 6 to 64 +/- 7 mm/s (p less than 0.001) in grade III. The LVPWVdmax showed an increase from 68 +/- 15 to 91 +/- 15 mm/s (p less than 0.001) in grade I, from 57 +/- 17 to 86 +/- 18 mm/s (p less than 0.01) in grade II, and from 55 +/- 11 to 83 +/- 6 mm/s (p less than 0.01) in grade III. In the PWE, there was an improvement from 12.4 +/- 1.6 to 15.5 +/- 2.1 mm (p less than 0.01) in grade I; from 10.5 +/- 2.0 to 12.5 +/- 1.5 mm (p less than 0.02) in grade II; and from 9.4 +/- 1.5 to 14.4 +/- 1.5 mm (p less than 0.001) in grade III. In the LAEVR, there was also an improvement from 65 +/- 12 to 39 +/- 21% (p less than 0.01) in grade I.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Immunohistological study of histiocytic necrotizing lymphadenitis.

Immunohistological study of 18 cases of histiocytic necrotizing lymphadenitis (HNL) demonstrated numerous helper/inducer cells (OKT-4) and suppressor/cytotoxic cells (OKT-8) with activation (Tac) and proliferation (OKT-9) markers, and histiocytes (lysozyme, alpha-1 anti-chymotrypsin, OK-M1) in the affected areas. However, B cells (B-1), NK cells (Leu-7 and Leu-11), complement proteins and receptor (C4 and C3d receptor), and neutrophils (chloroacetate esterase) were scanty or absent in these foci. Activity of NK cells was also decreased in the peripheral blood of 2 cases examined. The results suggest that HNL might be induced by the abnormal T cell-histiocyte response against some causative agents which induce a similar reaction of delayed hypersensitivity type.

Adolescent↗

Golgi-specific localization of transglycosylases engaged in glycoprotein biosynthesis in suspension-cultured cells of sycamore (Acer pseudoplatanus L.).

Golgi complex and endoplasmic reticulum (ER) were isolated from suspension-cultured cells of sycamore (Acer pseudoplatanus L.) by stepwise sucrose density gradient centrifugation using protoplasts as starting material. The purity of the two organelle fractions isolated was assessed by measuring marker enzyme activities. Localization of glycolipid and glycoprotein glycosyltransferase activities in the isolated Golgi and ER fractions was examined; three glycosyltransferases, i.e., galactosyltransferase, fucosyltransferase, and xylosyltransferase, proved to be almost exclusively confined to the Golgi, whereas the ER fractions contained glycolipid glycosyltransferase. The Golgi complex was further subfractionated on a discontinuous sucrose density gradient into two components, migrating at densities of 1.118 and 1.127 g/cm3. The two fractions differed in their compositional polypeptide bands discernible from Na-dodecylsulfate gel electrophoresis. Galactosyltransferase distributed nearly equally between the two protein peaks and xylosyltransferase activities using the endogenous acceptor also appeared to be localized in the two subcompartments. By contrast, fucosyltransferase, engaged in the terminal stage of glycosylation, banded in the lower density fractions. Golgi-specific alpha-mannosidase, which is presumably engaged in the sugar trimming of Asn-N-linked glycoprotein carbohydrate core, was enriched fourfold in specific activity in the fractions of the higher density. The overall experimental results indicate that the cotranslational glycosylation of Asn-N-linked glycoproteins, e.g., polyphenol oxidase (laccase), takes place in the ER, while subsequent post-translational processing of the oligosaccharide moiety proceeds successively in the two physically separable compartments of the Golgi complex.

Endoplasmic Reticulum↗

Time-resolved x-ray study of effect of sinusoidal length change on tetanized frog muscle.

Time-resolved x-ray diffraction studies were done on frog skeletal muscles with synchrotron radiation by applying sinusoidal length changes of frequency 10 Hz and amplitude approximately 1% to isometrically contracting muscles at approximately 17 degrees C. Distinct periodic intensity changes were observed in the 14.3-nm myosin meridional reflection and the equatorial 1,0 and 1,1 reflections. Response of the 14.3-nm reflection to the sinusoidal length change was nonlinear, as evidenced by a large second harmonic in its oscillatory intensity change, whereas the response of the equatorial 1,1 reflection was closely linear, as evidenced by almost sinusoidal intensity change. Intensity change of the 1,0 reflection was nearly antiphase to that of the 1,1 reflection. Integral widths of the 14.3-nm meridional reflection measured along the meridian and of the equatorial 1,1 reflection remained almost constant during tension development, while that of the 1,0 reflection tended to decrease. The widths of the 14.3-nm meridional reflection perpendicular to the meridian and of the equatorial 1,0 reflection appeared to undergo oscillatory changes in response to the sinusoidal length changes.

Animals↗

Preferential secretion of R-type alpha-amylase molecules in rice seed scutellum at high temperatures.

Exposure of fresh scutella excised from 4-day-old rice seedlings to higher temperatures, (40-42 degrees C), drastically reduced the biosynthesis of alpha-amylase as determined by the incorporation of [(35)S]methionine into the immunoprecipitable product. However, the intracellular transport and extracellular secretion of the enzyme molecules were enhanced at high temperatures, indicating that the biosynthesis and secretion of alpha-amylase are distinguishable in their temperature dependency. At the higher temperature regime (>==40 degrees C), the complex-type alpha-amylase isoform, resistant to hydrolytic digestion by endo-beta-N-acetylglucosaminidase H (Endo-beta-H) was predominantly secreted, whereas at lower temperatures (<==15 degrees C), the isoform susceptible to Endo-beta-H attack was the major molecular form secreted.

Journal Article↗

Concentrations of glycine and serine in cerebrospinal fluid during disturbed consciousness; a study of the therapeutic effect of thyrotropin-releasing hormone on the consciousness level.

The concentrations of aliphatic amino acids (glycine, serine, valine, threonine, alanine, leucine, isoleucine) in lumbar cerebrospinal fluid from patients with consciousness disturbances and normal controls were measured. Thyrotropin-releasing hormone (TRH) was administered to patients and the changes of levels of consciousness and amino acid concentrations were followed before and after TRH administration. The concentrations of glycine and serine from patients were significantly higher than those from controls; they returned to the control values with improvement of consciousness disturbances. The influence of TRH upon these amino acid concentrations was not observed. These results suggest that within the central nervous system, an alteration of the level of consciousness is associated with a distortion of glycine and serine metabolism and that TRH itself has no influence upon these amino acid concentrations.

Adolescent↗

Heterogeneity of epithelial cells and reactive components in thymomas: an ultrastructural and immunohistochemical study.

Fourteen thymomas were studied by electron microscopy and immunohistochemistry. Based on the ultrastructure of the neoplastic epithelial cells in comparison with normal thymic epithelium, four cortical-, three mixed-, five medullary-, and two corpuscular-type tumors were categorized. Histologically the tumors of cortical type showed prominent lymphocytic infiltration, but scant interdigitating reticulum cells (IDCs) were demonstrated by immunoperoxidase method on paraffin sections with anti-S-100 protein antiserum. Fewer lymphocytes but more IDCs were present in the tumors of medullary and corpuscular types, although variable in those of mixed type. This corticomedullary difference among thymomas was confirmed in some of them by the immunoperoxidase method on frozen sections with monoclonal antibodies. The cortical-type tumors were HLA-DR positive in tumor cells and infiltrated predominantly with cortical thymocytes (OKT-6+, OKT-3-, both Leu 3a/3b+ and OKT-8+), whereas the medullary- and corpuscular-type tumors were HLA-DR positive primarily in IDCs but not in tumor cells and were infiltrated more with medullary thymocytes (OKT-6-, OKT-3+, either Leu 3a/3b+ or OKT-8+). The classification of thymomas based on neoplastic epithelial cells will serve to refine the traditional classification based on reactive lymphocytes.

Adult↗

Effect of indapamide on atrial natriuretic polypeptide receptor in spontaneously hypertensive rat kidney.

The effect of a hypotensive state on atrial natriuretic polypeptide (ANP) receptors of the kidney treated by indapamide was investigated in spontaneously hypertensive rats (SHRs). SHRs aged 12 weeks were injected intraperitoneally with indapamide (10mg/kg/day) for 10 days and an ANP radiolabeled receptor assay (RRA) was done on the 11th day. The systolic blood pressure of SHRs injected with indapamide (IDP group) was statistically lower than that of SHRs injected with 2% gum Arabic solution (control group). Concerning the RRA of ANP in the SHR kidney, high affinity and low capacity binding sites were observed in the IDP group (Kd = 0.220 +/- 0.059 nM, Bmax = 6.10 +/- 2.36 fmol/100 micrograms) compared with the control group (Kd = 0.401 +/- 0.147 nM, Bmax = 9.96 +/- 2.50 fmol/100 micrograms). These finding suggested that the hypotensive state induced by treatment with indapamide may change the ANP receptor in kidneys of a SHR.

Animals↗

PAS staining of eosinophils in semi-thin sections of bone marrow embedded in glycol methacrylate.

The usual periodic acid-Schiff (PAS) reaction of glycosaminoglycans is applicable to paraffin embedded material. A modification for water-miscible methacrylate embedded tissue suitable for correlative light and electron microscopic studies, which makes it possible to find the same stained cell in a semi-thin tissue section, is described. Eosinophil leukocytes in semi-thin sections from bone marrow were verified by electron microscopy after staining with the PAS reaction. Immature eosinophil leukocyte granules reacted with and without previous salivary treatment. This method facilitates the search for localization of glycosaminoglycans in scattered blood cells.

Animals↗

Structural changes during contraction in vertebrate skeletal muscle as studied by time-resolved X-ray diffraction technique.

To obtain information about the structural changes in vertebrate skeletal muscle during contraction, time-resolved X-ray diffraction studies were performed on the intensity changes of the 59 A and 51 A actin layer lines from bullfrog sartorius muscle during the isometric force development, and the intensity changes of the 143 A and 215 A myosin meridional reflections and of the 1.0 and 1.1 equatorial reflections when isometrically contracting muscle was subjected to sinusoidal length changes (1%, 5-10 Hz) with the following results. The integrated intensities of the 59 A and 51 A actin layer lines increased during the force development by 30-50% for the 59 A reflection, and by about 70% for the 51 A reflection compared to their respective resting values. These intensity changes were greater than those taking place during the transition from rest to rigor state, and observed to precede the intensity changes of the 429 A myosin off-meridional reflection and of equatorial reflections. When sinusoidal length changes were applied to the muscle generating steady isometric force, the resulting periodic intensity changes in the 1.0 and 1.1 equatorial reflections were in phase and in antiphase with the length changes respectively. On the other hand, the 143 A myosin reflection exhibited a characteristic periodic changes; its intensity reached a maximum at each boundary between the stretch and release phases of the length changes. These results are discussed in connection with the behaviour of the cross-bridges during contraction.

Actin Cytoskeleton↗