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Biomedical subjects

N Matsuo

Publications and source records attributed to N Matsuo.

At least 253 records · Page 14Linked to original sources

Expression pattern of acidic and basic fibroblast growth factor genes in adult rat eyes.

Although the retinal angiogenic and mitogenic factors have been identified to be acidic and basic fibroblast growth factors (aFGF and bFGF), little information has so far been available about the cells producing them and their function in retinal tissues. We found, by in situ hybridization, that the expression pattern of the aFGF gene differed remarkably from that of the bFGF gene in adult rat eyes. Our results demonstrated that the aFGF gene was produced by photoreceptor visual cells, neuronal cells in the inner nuclear layer and ganglion cells of the retina, in addition to pigment epithelial cells of the choroid, iris and ciliary body, and epithelial cells of the cornea, conjunctiva and lens, while bFGF was synthesized solely by the photoreceptor visual cells.

Animals↗

A ring X chromosome, 46,Y,r(X)(p22.33q28), as a cause of extreme short stature in a male.

We describe a 15 10/12-year-old boy (Tanner stage 4, peak growth velocity 7 cm/year) with a ring X chromosome who presented with extreme short stature (mean -5.3 SD) as the sole recognizable abnormality. His chromosome constitution was determined to be 46,Y,r(X)(p22.33q28) in 174 of 182 peripheral blood cells and in 35 skin fibroblasts. Of the remaining eight peripheral blood cells, five had a dicentric double-size ring and three had a smaller ring. Other laboratory studies for short stature were noncontributory. We suspect that the ring's specific behavior in mitosis or its effect on expression of the statural determinant on the X chromosome short arm may be responsible for short stature in this patient.

Child, Preschool↗

27 amino acid residues can be deleted from the N-terminus of human lymphotoxin without impairment of its cytotoxic activity.

In order to study the relationship between activity and structure of human lymphotoxin (hLT, 171 aa), we synthesized the gene (519 bp) for hLT and expressed it in Escherichia coli. Purification of the recombinant hLT from crude extracts was difficult because of the low level of expression of the gene. To improve the yield of the recombinant protein, we prepared five truncated genes for mutant proteins in which 25, 26, 27, 28 and 37 amino acid residues, respectively, were missing from the N-terminus. All of the genes were efficiently expressed and adequate amounts of mutant proteins were synthesized. The proteins were recovered mainly in the supernatant fractions after disruption of cells, with the exception of LT delta 37N, in which 37 residues were absent from the N-terminal region. Cytotoxic activities against mouse fibroblast L929 cells were detected in supernatant fractions that contained these mutant proteins, except in the case of LT delta 28N, which lacks the first amino acid residue conserved in both hLT and human tumour necrosis factor (hTNF). LT delta 27N, which is the smallest of the active proteins, was purified to homogeneity, and its cytotoxic activity was found to be similar to that of recombinant hTNF.

Amino Acid Sequence↗

Retinal circulation times in quantitative fluorescein angiography.

We tried to obtain an overview of the quantitative state of the retinal circulation. Optical density measurements by an image analyzer were performed on video fluorescein angiograms for the determination of dyedilution curves. To ensure that curves with a sharp peak were obtained, 1 ml sodium fluorescein 10% was flushed with 20 ml physiological saline. From dilution curves of a retinal circulation times, T(x) (x = 1, 25, 50, 75, and 100) and Tm, were calculated. T(1) corresponds to the difference in the time of initial dye appearance; T(50), to the so-called half-maxim time difference; T(100), to the difference in the time to peak intensity; and Tm, to the mean circulation time. T(50) showed the best reproducibility when it was examined at 49 retinal regions of 10 healthy volunteers with a double video-fluorescein angiogram that was obtained within 1 min. Normal values (mean +/- SD) at the temporal superior region of 37 healthy volunteers were as follows: T(1) = 0.87 +/- 0.66 s, T(25) = 1.52 +/- 0.48 s, T(50) = 1.83 +/- 0.50 s, T(75) = 2.12 +/- 0.56 s, T(100) = 2.73 +/- 0.76 s, and Tm = 2.69 +/- 1.25 s. We believe that these values give a general overview of the quantitative state of normal retinal circulation.

Adolescent↗

Evaluation of viral myocarditis in children by radionuclide method.

Evaluation of viral myocarditis is essential for the clinician to assess the prognosis. In this study, Tl-201 myocardial scintigraphy and Tc-99m gated cardiac blood pool scan were performed in 16 patients with myocarditis diagnosed by clinical symptoms and laboratory findings and these nuclear medicine techniques were followed up for 5 years. Exercise Tl-201 scintigraphy using a bicycle ergometer was performed in 8 patients by SPECT imaging. There were mild to severe persistent defects found in all cases (100%), but pressure rate products showed normal response. The Tl-201 defect ratio improved gradually, but did not change significantly. In the resting Tl-201 image one of 16 patients showed severe multifocal defects. LVEF increased significantly from 1 year to 5 years after onset, while RVEF measured by gated blood pool scans showed slight increases 3 years to 5 years after diagnosis. It was concluded that myocardial perfusion improved only incompletely. Cardiac function (LVEF and RVEF) improved gradually, and pressure rate products were normal. Myocarditis should therefore be followed up in order to assess the prognosis; moreover, the relationship of myocarditis to dilated cardiomyopathy needs to be further studied.

Child↗

Interrelationship between the concentrations of some elements in the organs of Japanese with special reference to selenium-heavy metal relationships.

Multi-element analyses were conducted on internal organs (cerebrum, cerebellum, heart, spleen, liver and kidney) of Japanese obtained from 45 forensic medical autopsy cadavers. Elements analyzed and analytical methods were as follows: Ca, Cd, Cu, Fe, K, Mg, Na, P and Zn by inductively coupled plasma atomic emission spectrometry; total Hg (T-Hg) and inorganic Hg (I-Hg) by cold vapour atomic absorption spectrometry; methyl Hg (MeHg) by gas chromatography; and Se by fluorometry. A significantly positive correlation between Se and T-Hg was observed in kidney, liver, heart and spleen. The T-Hg/Se molar ratio was less than 1 in all the organs examined. The correlation between Zn and Cd was significant in liver and kidney. Multiple regression analyses using Se as a dependent and I-Hg, MeHg, Zn, Cd, Cu as independent variables were conducted on each organ. Inorganic Hg was a significant independent variable in kidney, whereas in liver and spleen it was MeHg. Cadmium was significant in explaining the variations in Se in liver and kidney medulla, indicating Cd-Se co-accumulation in humans.

Adolescent↗

Cervical cancers in uterus didelphys.

Two cases of cervical cancer in uterus didelphys are presented. One was extensive adenocarcinoma and one was squamous cell carcinoma in situ. In both cases the cancers appeared to have originated separately in each cervix.

Adenocarcinoma↗

Mutational analysis of structure--activity relationships in human tumor necrosis factor-alpha.

To determine the region of human tumor necrosis factor-alpha (TNF-alpha), essential for cytotoxic activity against mouse L-M cells, single amino-acid-substituted TNF-alpha mutant proteins (muteins) were produced in Escherichia coli by protein engineering techniques. An expression plasmid for TNF-alpha was mutagenized by passage through an E. coli mutD5 mutator strain and by oligonucleotide-directed mutagenesis. Approximately 100 single amino-acid-substituted TNF-alpha muteins were produced and assayed for cytotoxic activity. The cytotoxic activities of purified TNF-alpha muteins, e.g. TNF-31T, -32Y, -82D, -85H, -115L, -141Y, -144K and -146E, were less than 1% of that of parent TNF-alpha. These results indicate that the integrity of at least four distinct regions of the TNF-alpha molecule is required for full biological activity. These regions are designated as follows: region I, from position 30 to 32; region II, from position 82 to 89; region III, from position 115 to 117; region IV, from position 141 to 146. In addition, TNF-141Y could not completely compete with parent TNF-alpha for binding to the receptor. This demonstrates that region IV, and at least aspartic acid at position 141, must be involved in the TNF receptor binding site.

Amino Acid Sequence↗

Acute retinal necrosis as a novel complication of chickenpox in adults.

Three patients in their 20s suffered from chickenpox while in an immunocompromised state: one in pregnancy, one during a long course of corticosteroid for severe nephrotic syndrome, and the third with repeated upper airway infection due to bronchiectasis. They developed acute retinal necrosis about three weeks after the onset of chickenpox. Since acute retinal necrosis threatens sight, this unusual complication of chickenpox in adults needs serious consideration.

Acute Disease↗

Retinal pigment epithelial tear in reactive lymphoid hyperplasia of uvea.

A 76-year-old patient developed cystic exudative retinal detachment with many yellowish subretinal precipitates and a large retinal pigment epithelial (RPE) tear in midperiphery of the right eye in the course of polyclonal hypergammaglobulinemia. The left eye showed localized RPE detachment in the posterior pole which gradually extended. Systemic steroid administration reduced the subretinal precipitates to some extent, but suspicion of malignancy led to enucleation of the right eye after unsuccessful diagnostic vitrectomy. A histopathological study revealed massive infiltration of the uvea with plasma cells and small lymphocytes but no abnormal cells. This is the first report to show the association of an RPE tear with reactive lymphoid hyperplasia of the uvea.

Aged↗

Unusual exudative retinal detachment 9 months after scleral buckling surgery.

A 49-year-old man developed exudative retinal detachment 9 months after uncomplicated scleral buckling surgery in the left eye. The subretinal exudates were strictly localized along the buckle and showed remarkable response to steroid. The cause would be noninfectious inflammation like posterior scleritis, triggered by the buckle itself or its associated factors. It is important to note that subretinal exudates long after scleral buckling can occur in consequence of steroid-responsive inflammation as well as insidious bacterial or fungal infection described previously.

Exudates and Transudates↗

Retinal vasculitis as a complication of rheumatoid arthritis.

Two middle-aged women developed retinal vasculitis in the moderately active phase of classical rheumatoid arthritis. Fluorescein angiography disclosed diffuse leakage from the retinal capillaries and cystoid macular edema, which subsided in response to oral steroid. They did not show any clinical signs of vasculitis in other parts of the body. Retinal vasculitis should be included in the list of complications observed in rheumatoid arthritis.

Adrenal Cortex Hormones↗

Dipyridamole-induced ischemia in a child with jeopardized collaterals after Kawasaki syndrome.

The case of a 4-year-old boy with dipyridamole-induced ischemia is herein reported. The patient developed typical Kawasaki syndrome at 2 years of age, accompanied by coronary aneurysms in the left coronary artery (LCA) and the right coronary artery (RCA). The LCA was totally occluded at segment 6 and a distal area of the left anterior descending artery (LAD) was supplied by collaterals from the conus branch and the posterior descending artery (PD). Thallium-201 (Tl-201) myocardial scintigraphy was performed with intravenous administration of dipyridamole (DIP). DIP was infused at a dosage of 0.6 mg/kg for 5 min. Three minutes after the injection, myocardial ischemia occurred. Although 4 mg/kg of aminophylline was administered, the symptoms lasted for 20 min. Electrocardiogram suggested that ischemic lesions were located in the anteroseptal and inferior wall. Collaterals from PD could be recognized as jeopardized vessels and these collaterals probably participated in the ischemic attack. DIP could have increased the coronary flow into the uninvolved proximal branches of RCA. Subsequently DIP reduced coronary flow in the distal region of the stenotic RCA. Although T1-201 myocardial scintigraphy with DIP is a useful technique to estimate viability of the ischemic myocardium, it should be performed prudently in patients with multivessel diseases, such as those with jeopardized collaterals secondary to Kawasaki syndrome.

Child, Preschool↗

Structure of rice-straw arabinoglucuronoxylan and specificity of Streptomyces xylanase toward the xylan.

Rice-straw treated with 5% ammonia water was hydrolyzed with the beta-xylanase of Streptomyces sp. E-86, and four kinds of hetero-oligosaccharides, two arabinoxylo- and two glucuronoxylo-oligosaccharides, were isolated from the hydrolysate by charcoal column, gel filtration, ion-exchange, and aminopropyl silica column chromatographies. The structures of the oligosaccharides were identified as 3(2)-alpha-L-arabinofuranosyl-xylobiose, 3(2)-alpha-L-arabinofuranosylxylotriose, 2(3)-4-O-methyl-alpha-D-glucuronosylxylotriose, and 2(3)-alpha-D-glucuronosylxylotriose by the analysis of component sugar, partial acid hydrolysis, methylation analysis etc. Based on the structures of above oligosaccharides, the structure of rice-straw arabinoglucuronoxylan and the specificity of the xylanase toward the xylan are discussed.

Carbohydrate Conformation↗

No major defect detected in the gene of familial hypo-retinol-binding proteinemia.

Retinol-binding protein (RBP), a plasma protein with a molecular weight of 21,000 daltons, binds to retinol with a 1:1 molar ratio and transports it to the peripheral tissues. Familial hypo-retinol-binding proteinemia (hypo-RBPnemia) was detected in a 2-year-old girl who developed keratomalacia, and in her mother and sister. They persistently showed half the normal levels of RBP and retinol. Restriction fragments of leukocyte DNA, created by digestion with BamHI, EcoRI and PstI when human RBP complementary DNA was used as a probe, showed the same patterns in both the affected and unaffected family members. These results indicate that familial hypo-RBPnemia could be attributed to such minor changes as point mutations, rather than large deletion or insertion in the RBP gene.

Blotting, Southern↗

[The immunohistochemical analysis of necropsy eyes and brain lesion in a case of intraocular and brain malignant lymphoma].

A case of intraocular and brain malignant lymphoma was presented in which histopathological and immunohistochemical analysis of the necropsy eyes and brain lesions were performed. Lymphoma cells infiltrated into both eyes and the brain. The tumor cells could be found only in the vitreous cavity, not in other ocular tissues. Lymphoma cells were morphologically better preserved in the vitreous cavity, than in the vitrectomized specimen. Applying immunoperoxidase techniques to the necropsy eyes and brain lesions, the lymphoma cells were identified a B cell type, and the diagnosis of vitreous biopsy specimen was confirmed.

Brain↗