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Biomedical subjects

Y Obara

Publications and source records attributed to Y Obara.

At least 109 records · Page 6Linked to original sources
PubMed1987

Sectional classification of cataract.

It is of importance to epidemiologically explore the risk factors which will induce cataract. Both the sections of lenses and their grades of opacity were classified only on the basis of the findings by the slitlamp microscope in order to examine the cases with cataract. There are split ways for classification of the cases with cataract, but it would be of no meaning if the classification for this purpose is not generally utilized, no matter how detailed it may be. Therefore, a simplified method for classification was discussed in the present study. There were variations in the grades of opacity with the sections of the lens, and the variations give different effects upon the visual disturbances. Especially, it was conceived that the visual power would be affected by the opacity of the posterior cortex. Also, it was conceived that the opacity of the posterior cortex tends to advance faster.

Cataract↗
PubMed1986

Immunohistochemical distribution of ferritin, lactoferrin, and transferrin in granulomas of bovine paratuberculosis.

Granulomatous lesions of bovine paratuberculosis contained ferritin, lactoferrin, and a small amount of transferrin, as demonstrated by the immunohistochemical method. Macrophages in the normal bovine ileum did not contain lactoferrin and transferrin; however, ferritin was found in individual macrophages of Peyer's patches. These results may help elucidate the relationship between intracellular growth of Mycobacterium paratuberculosis and the presence of iron-binding proteins in the granulomas.

Animals↗
PubMed1986

Effects of aging on the formation of ester forms of riboflavin in the rat lens.

We studied the effects of aging on the formation of ester forms of riboflavin in the lens of rats. The formation was highest in newborn and 2-week-old rats; a sharp decrease was noted at one month, thereafter it continued to decrease gradually reaching a plateau at 3 months. In general, esterification of riboflavin was higher in female than male rats. We found that a decrease in the esterification of riboflavin with increasing age is a characteristic change in the rat lens. This finding may help to clarify the pathogenesis of senescent change in the lens.

Aging↗
PubMed1985

Clinical application of NMR-CT for idiopathic cardiomyopathy.

The accuracy of a newly developed nuclear magnetic resonance-computed tomography (NMR-CT) technique in diagnosing idiopathic cardiomyopathy was assessed and compared with other procedures such as echocardiography, coronary angiography, left ventriculography, myocardial biopsy, and electrocardiography. In case 1, the NMR-CT clearly revealed thickening of the lateral ventricular free wall and ventricular septum, which strongly suggested hypertrophic cardiomyopathy. Catheterization showed a pressure gradient of 54 mm Hg and this patient was diagnosed as having hypertrophic obstructive cardiomyopathy. In case 2, the NMR-CT showed dilatation of the ventricular cavity indicative of dilated cardiomyopathy. This was confirmed by echocardiography, which revealed the enlarged cavity of the ventricle and poor movement. In case 3, the patient had marked hypertension; the cardiac silhouette was enlarged, but the NMR-CT revealed that the ventricular free wall and septum were of normal thickness. This study shows that NMR-CT is of value in the differential diagnosis of idiopathic cardiomyopathy.

Adult↗
PubMed1985

Retinal damage in hatched chicks induced by formoguanamine. Decrease in ornithine aminotransferase activity and vitamin B6 content.

Subcutaneous injection of formoguanamine (2,4-diamino-s-triazine) induced sightlessness in newly hatched chicks within 28-32 hr. The specific activity of retinal ornithine aminotransferase, localized exclusively in the mitochondria of retinal pigment epithelium, and the retinal vitamin B6 content decreased rapidly after formoguanamine administration. An absorption spectrum of retinal extract showed reduced absorbance at 400 nm in the formoguanamine-treated chicks, but delta 1-pyrroline-5-carboxylate reductase, an enzyme in the retinal cytosol, did not change significantly. A drug-metabolizing enzyme, glutathione transferase, showed an increase in specific activity during a later phase. Histological examination of the formoguanamine-treated chicks revealed characteristic degeneration of pigment epithelium and photoreceptors, acute retinal detachment and a secondary gliosis in the outer nuclear layer. From these findings it may be concluded that formoguanamine primarily damages the physiological functions of retinal pigment epithelium and photoreceptors and results in irreversible retinal detachment in newly hatched chicks.

Animals↗
PubMed1984

Relationship between N-acetyl-beta-D-glucosaminidase activity and cell count, lactose, chloride, or lactoferrin in cow milk.

Activity of N-acetyl-beta-D-glucosaminidase was measured in foremilk samples collected from cows. A total of 64 samples were collected from these cows, some of which were affected by mastitis. They were examined for N-acetyl-beta-D-glucosaminidase activity, cell count in whole milk, and milk chloride, lactose, and lactoferrin. The correlation coefficient was .72 between activity and cell count, -.80 between activity and lactose, and .88 between activity and chloride. Therefore, the correlations between N-acetyl-beta-D-glucosaminidase activity and milk components, chloride and lactose, were larger than that between N-acetyl-beta-D-glucosaminidase activity and cell count. The correlation coefficient was high (.91) between N-acetyl-beta-D-glucosaminidase and lactoferrin. The N-acetyl-beta-D-glucosaminidase activity in cow's milk has potential for diagnosis of mastitis.

Acetylglucosaminidase↗
PubMed1982

Chromosomal investigations of the Usubuchi sarcoma. II. Chromosomal alteration of the stem line cells revealed by differential staining techniques.

Stem line cells of the Usubuchi sarcoma (US) were karyologically investigated by means of G-, C-, and N-banding methods in ten samples from the 1,923rd to 2,081st transfer generations, with special attention to the structural alteration of marker-1 chromosome. The US cells showed wide variations in chromosome constitution and number, while the modal number of chromosomes was consistently 64 in all the generations examined. The chromosome constitutions varied widely even in cells with the modal number. In the early stage (1,923rd to 1,936th generations) the US contained two major stem lines characterized by marker combinations such as 1-2-3-4(1)-4(3)-8 and 2-3-4(1)-4(2)-4(3)-8, occurring with nearly similar frequency. From the middle to later transfer stages (from the 2,004th to the 2,081st generations), the 1-2-3-4(1)-4(3)-8 stem line rapidly declined and finally disappeared. In contrast, the 2-3-4(1)-4(2)-4(3)-8 line became a predominant part of the stem line. The G- and C-banding and population analyses of the stem line cells strongly suggested that marker 4(2) might have been derived from marker 1 by a deletion of the distal half of its long arm. The US studied contained a few stem lines and various types of sublines, each karyologically characteristic. G-Banding analysis revealed various types of intra- and interchromosomal rearrangements probably due to occasional chromosomal mutations either in markers or in nonmarkers in both stem lines and sublines. It seems likely that the stem line cells of the US are not always stable, but rather variable, in their chromosome makeup during the course of multiplication and successive transfers.

Animals↗
PubMed1982

Developmental changes of carbonic anhydrase activity of parotid gland and stomach of goat.

1. Carbonic anhydrase activities in the various tissues of ruminants and non-ruminants were compared. 2. The highest activity was found in the parotid gland of ruminants such as bovine and goat. However the activity in the kidney was not significantly different between the ruminants and non-ruminants. #. The effect of development on the carbonic anhydrase activity was studied. The activities in both the parotid gland and kidney of the goat were found to increase with age whereas the activities of the pancreas, liver and submaxillary gland did not change significantly. 4. The activities in the abomasum of the goat also increased with age however the other stomachs did not vary prominently.

Animals↗
PubMed1981

Preservation and transportation of bacteria by a simple gelatin disk method.

A wide range of bacterial species, e.g., Enterobacteriaceae and Neisseria, Streptococcus, Branhamella, Haemophilus, Gemella, Pseudomonas, Flavobacterium, and Bacteroides species, were successfully preserved for 1 to 5 years by our gelatin disk drying method. The beta-lactamase activity of penicillinase-producing Neisseria gonorrhoeae was retained for more than 3 years with this method. Good results were also obtained upon airmailing many strains of N. gonorrhoeae embedded in gelatin disks from Japan to the United States. Neisseria, Branhamella, Gemella, and Haemophilus organisms suspended in the reagent used in the preparation of the gelatin disks could be preserved for 6 to 12 months after freezing the cell suspensions at -20 degrees C. Furthermore, modification of our gelatin disk preservation method made possible the safe long- and short-distance transportation of clinical isolates. Our methods can be used by any small laboratory, since they require only conventional instruments and reagents.

Bacterial Infections↗
PubMed1980

The appearance of re-cycled urea in the digestive tract of goats during the final third of a once daily feeding of a low-protein ration.

1. An experiment was carried out with goats fed on a low-protein ration to clarify the importance of the rumen and significance of saliva in the appearance of re-cycled urea in the digestive tract during the final third of a once daily feeding regimen. The isotope-dilution method with [15N]urea and 15NH4Cl was used. 2. When the serum urea level was 58 mg N/l, the amount of urea transferred from the blood urea pool to the rumen ammonia pool was 48.6 mg N/h, which was estimated to be approximately 43% of the total amount of urea having appeared in the NH3 pool of the digestive tract. When the serum urea level was 106 mg N/l, the corresponding amount of NH3 was 77.7 mg N/h, which was estimated to be approximately 46% of this total amount. 3. The amount of saliva secreted was measured directly by the oesophageal fistula method. Salivary secretion serves as a mode of transfer of blood urea to the rumen NH3 pool. Then the ratio, salivary secretion:diffusion through the rumen wall during the final third of the cycle was calculated to be 1:4-1:6. 4. In goats fed on a low-protein diet, the rumen is an important site of appearance of blood urea in the digestive tract. It was verified that the principal mode of transfer of blood urea to the rumen was the direct diffusion through the wall of the rumen.

Ammonia↗