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Biomedical subjects

M Fukuda

Publications and source records attributed to M Fukuda.

At least 1,441 records · Page 80Linked to original sources

Cytofluorometric analysis of cell proliferation and differentiation of the human erythroblasts.

The method of cytofluorometric measurement of the contents of Hb and nuclear DNA on a single erythroid cell (Fukuda et al., l975; 1977a) was used for the quantitative analysis of the erythropoiesis in normal bone marrow. The intracellular Hb in an erythroid cell was converted to fluorescent porphyrin after removing the Giemsa staning by irradiation with violet light in the presence of SH-donor (mercaptoethylamine hydrochloride, MEA) and its nuclear DNA was subsequently stained with pararosaniline Feulgen staining. With the two quantitative parameters, Hb content and DNA amount, the erythroid cells in normal human bone marrow were classified into 6 classes of different maturation stages (EI-EIV). The morphological characteristics of the most primitive erythroblast (EI cells) were described. The "proerythroblasts" which were identified on the bases of morphological criteria had in general aneuploid amounts of nuclear DNA with disproportional contents of Hb, thereby indicating that they are rather aberrations from the normal steps of cell maturation. The DNA amounts of "orthochromatic erythroblasts" (EV cells) showed continuous decrease from diploid range to almost zero suggesting that the removal of nuclear DNA from the erythroblast is not exclusively due to mechanical explusion of a whole intact nucleus.

Adult↗

Standardization of the post-irradiation method to eliminate primary fluorescence in cytofluorometry.

Thorough irradiation of specimen with the strong excitation light after fluorescent Feulgen staining destroys the primary fluorescence in the background with stabilization of specific fluorescence of pararosaniline (post-irradiation method). An apparatus to perform effective post-irradiation was developed and irradiation condition for DNA cytofluorometry on a pararosaniline Feulgen stained smear was standardized. After 10 h irradiation on this condition, the primary fluorescente in the background is almost completely cleared away. Proportionality between amount of fluorescence and DNA content is perfectly preserved and standard deviation in each class of ploidy becomes to be less than 5% of the mean DNA value. The standardized post-irradiation enables us to obtain reproducibly the same values of fluorescence on Feulgen stained nuclei of the same cell population in different smears even if the staining conditions in Schiff's solution might be different to some extent.

Animals↗

Purification of rat intestinal receptor for intrinsic factor-vitamin B-12 complex by affinity chromatography.

Rat intrinsic factor was bound to vitamin B-12-Sepharose to produce intrinsic factor-vitamin B-12-Sepharose. Intestinal receptor for intrinsic factor-vitamin B-12 complex was purified from rat ileal extract by affinity chromatography using the intrinsic factor-vitamin B-12-Sepharose as an affinity adsorbent with recovery of 48.5% and specific activity increased 335 fold of original sample.

Animals↗

The structure of unit B-type glycopeptides from porcine thyroglobulin.

The structure of Unit B-type glycopeptides (monosialo-type and disialo-type) was investigated by Smith degradation, methyllation, and mass spectral analysis. These glycopeptides contain three peripheral sugar chains. Two are composed of D-galactose residues linked at C-6 and 2-acetamido-2-deoxy-D-glucose residues linked at C-4, and the other is composed of a D-galactose residues linked at C-6, a 2-acetamido-2-deoxy-D-glucose residues linked at C-4, and a D-mannose residue linked at C-2. Most of these peripheral sugar chains are linked to two inner D-mannose residues which are substituted at C-3 and C-6, and constitute branching points. L-Fucose and N-acetyl-neuraminic acid residues are nonreducing terminal groups, and a di-N-acetylchitobiose moiety is linked to an asparagine residue in the peptide moiety. By methylation analysis of the oligosaccharide obtained by hydrazinolysis of the disialoglycopeptide, the L-fucose residues was found to be linked to C-6 of the 2-acetamido-2-deoxy-D-glucose residue linked to the asparagine residue. From these results, and from the previously reported data on the sugar sequence and the anomeric configurations of the linkages between sugar residues, structures for these glycopeptides are proposed.

Animals↗

Reconstitution of tobacco mosaic virus rods occurs bidirectionally from an internal initiation region: demonstration by electron microscopic serology.

RNA of a common strain of tobacco mosaic virus was sequentially reconstituted first with protein of the same strain and then with protein of a tomato strain. The reconstituted particles were treated with specific antibodies against the two strain particles and were examined electron microscopically to locate the regions of rods encapsidated with the respective proteins. The results demonstrated that reconstitution starts at an internal region of the RNA about 830 nucleotides from an end that recent studies indicate to be the 3' terminus. Evidence was obtained to show that reconstitution proceeds toward the 5' terminus of the RNA until it is fully encapsidated. Encapsidation of the 3' distal portion of the RNA apparently occurs later and in a direction opposite to that of the encapsidation of the 5' distal portion.

Binding Sites↗

High prevalence of e antigen among healthy blood donors carrying hepatitis B surface antigen in Japan.

Hepatitis B surface antigen (HBsAg) was detected by an immune adherence haemagglutination method in the serum samples of 292 voluntary, apparently healthy blood donors at four regional blood centres in Japan. Their serum samples were concentrated 3-fold and tested for e antigen (e Ag) and antibody to e (anti-e) by immunodiffusion. The e Ag was found in 41 samples (14.0%) and anti-e in 57 (18.6%). When 100 randomly selected serum samples containing HBsAg were tested as they were (unconcentrated), and at 3- and 5-fold concentrations, e Ag was detected in 3, 16 and 27, respectively, and anti-e in 10, 21 and 26. Subtypes of HBsAg were similar in carriers with e Ag and with anti-e. There is a high prevalence of e Ag in healthy individuals in Japan. There are also high rates of vertical transmission of hepatitis B virus from mothers to children, as well as a high incidence in the past of post-transfusion hepatitis. This is further evidence that e antigen is a marker for the infectivity of hepatitis B virus in carriers.

Blood Donors↗

Echocardiographic features of straddling mitral valve.

A case of straddling mitral valve associated with double outlet right ventricle and coarctation of the aorta is presented. Radical operation (Jatene's procedure) was performed under the diagnosis of complete transposition of the great arteries associated with coarctation of the aorta. The patient could not survive the operation. Autopsy revealed that both of the great vessels originated in the right ventricle (double outlet right ventricle). In addition to this abnormality, some of the chordae of the mitral leaflet were attached to the right ventricular wall through the ventricular septal defect (straddling mitral valve). Echocardiograms recorded prior to the operation revealed feactures corresponding to the anatomical abnormalities, including that the anterior mitral leaflet moved far anterior to the ventricular septum. This is the first case of echocardiographic features of straddling mitral valve.

Aorta↗

Ultrasonic studies on endocardial fibroelastosis.

Four patients with endocardial fibroelastosis were studied by two-dimensional and M-mode echocardiography. The two-dimensional echocardiography showed the characteristic echo from the abnormally thickened endocardium of the left ventricle in every case. Of the 4 cases, 2 were still suffering from congestive heart failure at the time of the study and the other 2 had been already free from clinical symptoms. In the former group, the ultrasonic findings revealed an enlargement of the left ventricle (large left ventricular dimension index) and poor movement of the anterior mitral leaflet which was indicated by a decrease in the diastolic descent rate. The latter group presented almost normal findings concerning the above points. The ultrasonic method is thus proved to be very useful for the diagnosis and evaluation of clinical conditions in cases of endocardial fibroelastosis.

Child↗