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Biomedical subjects

M Sakai

Publications and source records attributed to M Sakai.

At least 595 records · Page 33Linked to original sources

Purification and characterization of an antibacterial and antineoplastic protein secretion of a sea hare, Aplysia juliana.

The fetid secretion of a sea hare, Aplysia juliana, was lethal to crabs and also inhibited the growth of bacteria. When the secretion was partitioned between water and n-hexane, only the n-hexane layer, which had a nauseating odor, was lethal to crabs. The water-soluble fraction showed strong antibacterial activity and inhibited the growth of both Gram-positive and Gram-negative bacteria. Antibacterial activity of the water-soluble fraction was destroyed by heating at 50 degrees C for 15 min, but was resistant to treatment with proteolytic enzymes. The active principle, named julianin-S, was purified by gel filtration and ion exchange chromatography. The purified specimen gave a single protein showing a mol. wt of approximately 67,000, as determined by gel filtration. Julianin-S inhibited the growth of Bacillus subtilis by 50% at a concentration of 70 ng protein/ml. It was also cytotoxic to murine tumor cells and inhibited in vitro growth of L1210 cells by 50% at a concentration of 8 ng protein/ml.

Animals↗

Production of bovine identical twins via transfer of demi-embryos without zonae pellucidae.

Embryos were collected nonsurgically from nåturally-cycling or superovulated donors 7 d after estrus. Forty-four morulae, early blastocysts and blastocysts classified as good to excellent were bisected using a fine glass needle to produce forty-four identical demi-embryos. The bisected demi-embryos, without zonae pellucidae, were nonsurgically transferred, either by twin or single transfer. An additional forty-eight embryos were collected from the same donors and transferred as a control. Among the twin transfers, 8 of the 13 recipients became pregnant (61.5%). Seven of them conceived twin fetuses (87%) and one a single fetus. However, only two sets of normal identical twin calves were obtained. Among the single transfers, 72.6% (45/62) of bisected embryos without zonae pellucidae resulted in pregnancy, of which 48.4% (30/62) were identical twins, and 24.2% (15/62) were singletons. Another 27.4% (17/62) of the recipients did not became pregnant. The pregnancy rate for whole embryos with zonae pellucidae was 72.9% (35/48). These data show that there was no significant difference between the pregnancy rates of bisected embryos without zonae pellucidae and whole embryos with zonae pellucidae transferred 7 d after estrus. Bisection of bovine embryos was simplified and even morula stage embryos were transferred without zonae pellucidae.

Journal Article↗

Clinical usefulness of dual-label Schilling test for pancreatic exocrine function.

The usefulness of the pancreatic dual-label Schilling test as an indirect test of pancreatic exocrine function was evaluated. This dual-label Schilling test was based on the difference of absorption for [58Co]cobalamin bound to hog R protein and [57Co]cobalamin bound to intrinsic factor. In this study, the test was performed in 7 normal subjects, 5 patients with pancreatectomy, 12 patients with chronic pancreatitis, 10 patients with suspicion of chronic pancreatitis, and 13 patients without chronic pancreatitis. The normal lower limit (mean -2 SD) of excretion ratio for [58Co]/[57Co] in 24-h urine was 0.68. Of the 26 patients on whom endoscopic retrograde pancreatography was performed, none of the 9 patients with normal pancreatogram, 4 of the 9 patients with mild to moderate pancreatitic changes in pancreatogram, and 7 of the 8 patients with advanced pancreatitic changes in pancreatogram showed a positive value lower than the ratio of 0.68 in this test. In 28 patients examined with the direct test of pancreatic secretory capacity, 2 of the 13 patients with normal function, 6 of the 9 patients with mild dysfunction, and 5 of the 6 patients with definite dysfunction were positive in this test. The results of the pancreatic dual-label Schilling test significantly correlated with those of a direct test of pancreatic secretory capacity and the findings of pancreatitic changes in pancreatogram (p less than 0.01, chi 2 test). The ratio for [58Co]/[57Co] correlated (r = 0.73) with the maximal bicarbonate concentration in duodenal juice of the direct test of pancreatic secretory capacity. The impairment of bicarbonate output by the pancreas may adversely affect the transfer of cobalamin from R protein to intrinsic factor. It suggested that the pancreatic dual-label Schilling test is useful for detecting not only patients with severe pancreatic insufficiency but also the relatively early stage of chronic pancreatitis with bicarbonate secretory dysfunction of the pancreas.

4-Aminobenzoic Acid↗

[Synthetic cephalosporins. IV. Synthesis and antibacterial activity of 7 beta-[(Z)-2-(2-aminothiazol-4-yl)-2-(O-substituted oxyimino)acetamido]-3-(1,2,3-triazol-1-yl)methyl-3-cephem-4-carboxylic acid and related compounds].

Synthesis and oral activity of 7 beta-[(Z)-2-(2-aminothiazol-4-yl)-2-(O-substituted oxyimino)-acetamido]-3-(1,2,3-triazol-1-yl)methyl-3-cephem-4 -carboxylic acid and its related compounds were described. 3-(1,2,3-Triazol-1-yl)methylcephalosporins have been prepared by the direct cycloaddition of acetylene to 3-azidomethylcephalosporins, which were obtained by nucleophilic substitution of 3-chloromethylcephalosporins with sodium azide in N,N-dimethylformamide. The cephalosporins (8a--c) had potent and wide antibacterial spectra against gram positive and gram negative bacteria which were comparable to those of cefixime or cefteram. Urinary recovery of 9a and 9b, pivaloyloxymethyl esters of 8a and 8b, were 9.2% and 3.5%, respectively, through oral administration in mice, exhibiting lower rate than that of cefteram pivoxyl (28%).

Animals↗

Influence of water-immersion stress on synthesis of mucus glycoprotein in the rat gastric mucosa.

Gastric mucous cells of rats subjected to water-immersion stress were incubated with [3H]-palmitic acid and [14C]-N-acetylgalactosamine. The peptidyl-tRNA released by gastric polysomes was precipitated with cold ethanol and then the content was determined. A 70% reduction in the peptidyl-tRNA isolated was observed in the stressed rats, as compared with in control rats. The peptide recovered from the peptidyl-tRNA showed 30-50% less [3H]-palmitic acid and [14C]-N-acetylgalactosamine incorporation in the stressed rats than in normal controls. It was thus suggested that translation, acylation and glycosylation of the peptides in the ribosomes of the gastric mucosa were remarkably affected by the stress.

Acetylgalactosamine↗

[Immunohistochemical study on the primary olfactory neuron of rat and suncus].

Carnosine (beta-alanyl-L-histidine), a putative neurotransmitter, was identified immunohistochemically in the primary olfactory neuron, using newly developed anti-carnosine antiserum. Similar results were obtained in the rat and suncus. Carnosine-like immunoreactivity was observed in the olfactory cells and its apical dendrites of the olfactory epithelium. The olfactory nerve and glomerular layer of the olfactory bulb showed positive reaction. At electron microscopic level, carnosine-immunoreactive end products widely spread out in the cytoplasm of olfactory nerve cells and also on microtubules of olfactory cilia. In the glomerular layer, reaction products were found diffusely in many axon terminals. These terminals had small spherical vesicles and often made asymmetric synaptic contacts to the second neuron. Unilateral closure of the olfactory naris resulted lower immunoreactivity of tyrosine hydroxylase in periglomerular cells, which are dopaminergic interneurons and are thought to regulate neurotransmission of olfactory input. In contrast no remarkable changes were seen on carnosine immunoreactivity in olfactory bulb. The present results suggest that carnosine may play some important roles in the olfactory mucosa. The functional role of carnosine remarks to be further examined.

Animals↗

Comparative bond strengths of plastic teeth to microwave-curing, heat-curing and 4-META containing denture base resins.

Bond strength of hardened plastic teeth or acrylic resin teeth to microwave-curing, conventional heat-curing and 4-META-containing denture base resins were comparatively investigated in this study. Effects of grinding and monomer coating of the tooth ridge lap were also studied. Bond strength of plastic denture teeth to microwave-curing denture base resin was slightly higher than the other two resins. With all denture base resins used, an increased bond strength was obtained with hardened plastic teeth by treatment of tooth ridge lap but not with acrylic resin teeth. However, scattering of the bond strength was reduced by treatment of tooth ridge lap in acrylic resin teeth specimens. With hardened plastic teeth specimens, fracture in the base resin was increased by monomer coating. With acrylic resin teeth specimens, no specific fracture patterns were demonstrated by treatment of tooth ridge lap. Fracture occurred mostly in the acrylic resin teeth. These results suggest that bond strength of both denture teeth to microwave-curing or 4-META-containing denture base resin was increased or solidified by grinding or monomer coating of tooth ridge lap.

Acrylic Resins↗

Abrasion resistance of microwave-curing denture base resin.

This study was designed to test the abrasion resistance of microwave-curing denture base resin. We also studies the effects of surface smoothing treatment on abrasion resistance. Test resin was allowed to polymerize, and then buff polished or treated by surface smoothing. Knoop hardness was measured both prior to and following surface treatment. Then, the test material was subjected to brushing using a newly developed toothbrushing machine. Volume and surface roughness of the material were measured before and after brushing, and the surface structure of the material was examined with SEM. Microwave-curing denture base resin is equal in Knoop hardness and abrasion resistance to its conventional heat-curing counterpart, although it is smoother at the surface. The resin improved both in hardness and abrasion resistance when it underwent surface smoothing treatment regardless of whether it was heat-cured or microwave-cured. As was evident from SEM observations that both types of resins suffered superficial chipping following severe brushing, which is in accordance with our previous clinical findings.

Acrylic Resins↗

[Etiological study of relationship between impacted permanent teeth and malocclusion].

This investigation was undertaken to determine the causes of impacted permanent teeth and whether they have any influence on dentition, occlusion and skeletal patterns. The materials used were dental X-rays, occlusal dental X-rays, panoramic radiograms and cephalograms and dental casts of 194 cases (51 males and 143 females) which revealed impacted permanent teeth among 3979 cases (1215 males and 2764 females) from 1964 to 1985 in the Department of Orthodontics, School of Dentistry, Aichi-Gakuin University. The results obtained were as follows: 1. The incidence of impacted permanent teeth in these samples was 4.9% of the entire number of orthodontic patients. There was no significant difference between sexes. 2. The incidence according to the number of impacted permanent teeth was as follows: one impacted tooth, 74.8%; two impacted teeth; 21.1%, three impacted teeth; 3.6%, four impacted teeth; 0.5%. The incidence of two symmetrically impacted teeth was 61.5%. 3. As to the type of impacted teeth, the frequency of maxillary central incisors was the largest (33.7%), followed by 3 (25.0%), 5 (22.2%), 5 (11.9%), 2 (4.4%), 3 (1.2%), 4 (0.8%), 4 (0.4%), and 7 (0.4%). But no impacted teeth were found in the regions of 1, 2, 6, 6, 7 and 7. 4. As to impacted teeth and the type of malocclusion, the spaced arch in the anterior region had impacted teeth most frequently followed by crowding, open bite and lateral cross bite. Malocclusions with the smallest incidence were cross bite and upper protrusion. The spaced arch had a higher incidence of impacted teeth than bimaxillary protrusion. In the posterior region (impacted molar teeth), the lateral cross bite, spaced arch, and upper protrusion had impacted molars most frequently, crowding was second and cross bite had the least. 5. In the direction of long axis, the impacted tooth with a horizontal direction was found most frequently (35.2%), followed in the order of frequency by inverse direction (32.7%), labial or mesial tipping (22.0%), lingual or distal tipping (5.7%), and right-angled (4.4%). Moreover, the inverse maxillary central incisor and mesially tipped maxillary canine were found most frequently. The frequency of maxillary central incisors with crooked roots was 64.7%, which was higher than that of maxillary canines (19.0%). 6. Lack of space is the most frequently found cause of impacted teeth, and in the anterior region this was the main cause of canine impacted teeth. Eruption impediment by supernumerary teeth and trauma were found to be characteristic causes of anterior impacted teeth.

Adult↗

Clinical application of hair protein glycation in the assessment of blood glucose control and diabetic neuropathy.

Glycation of hair protein was assessed in diabetic patients by the measurement of furosine, which is derived from fructose-lysine, a glycated lysine residue in protein. The level of furosine in 12-cm-long hair which grew over the course of one year was significantly better correlated with the mean values of four determinations of fasting plasma glucose (FPG) and four determinations of hemoglobin A1c, respectively, at the time of hair sampling. The level of glycation in hair, which corresponds to the time taken for hair growth, may represent the mean level of blood glucose during the time corresponding to the growth period. The values of motor nerve conduction velocity and sensory nerve conduction velocity were better correlated with the level of furosine in hair corresponding in the length to 1 year's growth than the levels of FPG and hemoglobin A1c at the time of the determination of nerve conduction velocity. These results suggest that hair glycation may serve as a valuable indicator both of long-term blood glucose trends and of the relationship between diabetic complications and blood glucose.

Adult↗

The effect of fructose on collagen glycation.

The effect of fructose on the formation of advanced Maillard reaction products which have fluorescence and cross-links was investigated. Type I collagen was added to various concentrations of glucose and fructose which were then incubated at 37 C for 4 weeks. Both the level of furosine and the fluorescence intensity increased in direct proportion to glucose and fructose levels and to the duration of incubation. Incubation with fructose produced less furosine but more intense fluorescence than incubation with glucose. These results suggest that fructose in the polyol pathway plays an important role in the formation of advanced Maillard products.

Animals↗

Pseudomonas fluorescens isolated from the diseased rainbow trout, Oncorhynchus mykiss.

Pseudomonas fluorescens was isolated from the diseased rainbow trout, Oncorhynchus mykiss, in Iwate Prefecture. Typical symptoms of the diseased fish were hemorrhage at the bases of fin and anal region, and internally, petechia of each organ, especially the intestine. This bacterium was pathogenic to rainbow trout and Tilapia, Sarotherodon niloticus.

Animals↗

[Advance of disability and prognosis in Duchenne muscular dystrophy--a comparison between institutionalized care and home care].

Rate of advance of disability and age at death were studied in patients with Duchenne muscular dystrophy (DMD). A comparison was made between DMD patients under care in their own homes and those hospitalized in National Suzuka Hospital. In 45 patients with home care, rate of advance of disability was considerably high in their age of 6 to 12 years, the average being 0.83 stage per year after the N.Y. University-Ueda's rating stage of disability. In the age of 12 to 17 years, however, the disease progression was much slower, the average being 0.14 stage per year. Beyond 18 years old, the average stage of disability was constantly 7.7, meaning almost bedridden stage. On the contrary, in 56 patients with institutionalized care, the average rate of advance was lower, being 0.5 stage per year in the age of 7 to 15 years and 0.13 stage per year from 15 to 23 years of age. The result of statistical analysis indicated that the stage of disability was significantly higher in the patients under the home care than those with institutionalized care at the age of 12-16, 18 and 19 years. The age when the patients became unable to walk was 9.7 +/- 1.8 years (mean +/- SD) in those with home care and 10.9 +/- 2.3 years in those with institutionalized care. The difference was statistically significant (p less than 0.01). The age at death was 18.3 +/- 3.8 years in 19 DMD patients with home care and 20.4 +/- 3.6 years in 33 patients with institutionalized care. The difference was also statistically significant (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗