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Y Wakisaka

Publications and source records attributed to Y Wakisaka.

At least 37 records · Page 2Linked to original sources
PubMed1992

[A reproductive study of Weiser-Maples guinea pigs].

The Weiser-Maples (WE) guinea pig strain was introduced by Backshire Co., Ltd. (USA) in 1977. We have been breeding WE strain guinea pigs for skin melanization research. The WE guinea pig colony produced 1271 pups in 417 litters from May 1978 through December 1983. Breeding date are shown below. The mean litter size was 3.05, the stillborn rate was 15.2%, the weaning rate for live-born pups was 93.5% and the sex ratio was 1.01. The average age at first vaginal membrane rupture was 31.4 days at which time body weight was 290.5g. The mean length of the first 7 estrous cycles was about 17 days, with no cyclical variation in length. The mean duration of gestation was 67.9 days. Duration of pregnancy varied with litter size. There was an inverse relationship between litter size and duration of pregnancy. Most of the pups were delivered alive in mid-pregnancy with a parturition range of 56 to 76 days. The probability of pup death depends on gestational length: the lowest incidence of mortality was seen in litters born at 70 days. The mortalities were related to litter size but not to parity. There was an inverse relationship between birth weight and litter size. In WE guinea pigs, the mean weight for a litter of 1 was 120 g; for a litter of 5, the mean body weight was 58g. Male body weights were slightly heavier than female at birth and at weaning age. The mean body weights are shown below, date of birth: female 88.3g, male 93.3g, weaning age (2 weeks): female 181.1g, male 198.8g and 30 weeks: female 758.7g, male 1018.0g. These date for WE guinea pigs are comparable to those of other strains.

Animals↗
PubMed1992

[Congenital malformation of the skeleton in Weiser-Maples guinea pigs].

Some abnormalities were observed in the occipital bone, cervical vertebrae and thoracic vertebrae of Weiser-Maples guinea pigs. In the occipital bone, the medial basilar impression was suggested to occur in 40 (32.8%) out of 122 animals. The basilar impression was classified into right, left and both side types and observed in 24, 11 and 5 animals, respectively. The basilar impression was known to be accompanied in human with some anomalies such as platybasia, Klippel-Feil syndrome, deformation of foramen magnum and so-on. These anomalies were also observed in guinea pigs. The fusion of the axis with the 3rd cervical vertebra was observed in 12 (10.5%) out of 114 animals. The deformation was sometimes observed in the temporal, interparietal, atlas and axis as well as the occipital bone. The fusion of the 7th cervical vertebra with the 1st thoracic vertebra was found in 46 (51.7%) out of 89 animals. This fusion was thought to have no relation with the basilar impression. Weiser-Maples guinea pigs are now in 19 generations of sibmating. Because these abnormalities as mentioned above are all thought to be inherited, the selective breeding will make Weiser-Maples guinea pigs suitable for the study of the basilar impression.

Animals↗
PubMed1991

New operative method for distal aortopulmonary septal defect.

A new technique is described for repairing distal aortopulmonary septal defect with aortic origin of the right pulmonary artery in a 26-day-old neonate. To prevent the narrowing of the proximal right pulmonary artery in the distal aortopulmonary septal defect caused by conventional intraluminal prosthetic patch reconstruction, rerouting of the right pulmonary artery using native aortic wall tissue without artificial material was performed. This method seems to be superior to the conventional method, especially during the neonatal period.

Anastomosis, Surgical↗
PubMed1984

Isolation of L-cycloserine from Erwinia uredovora.

An antibiotic which seems to be a cell wall synthesis-inhibitor was isolated from a bacteria strain identified as Erwinia uredovora. The antibiotic was identified with L-cycloserine from its physico-chemical properties. This is the first example for isolation of L-cycloserine as a microbial product.

Cycloserine↗
PubMed1982

Formation of Crystalline delta-Endotoxin or Poly-beta-Hydroxybutyric Acid Granules by Asporogenous Mutants of Bacillus thuringiensis.

Parental strains and asporogenous mutants of Bacillus thuringiensis subspp. kurstaki and aizawai produced high yields of delta-endotoxin on M medium, which contained 330 mug of potassium per ml, but not on ST and ST-a media, each of which contained only 11 mug of potassium per ml. On ST and ST-a media, refractile granules were formed instead. These granules had no insecticidal activity against silkworms and were isolated and identified as poly-beta-hydroxybutyric acid. Supplementation of the potassium-deficient ST-a medium with 0.1% KH(2)PO(4) (3.7 mM) led to the formation of crystalline delta-endotoxin. The replacement of KH(2)PO(4) with equimolar amounts of KCl, KNO(3), and potassium acetate or an equivalent amount of K(2)SO(4) had a similar effect, whereas the addition of an equimolar amount of NaH(2)PO(4) or NH(4)H(2)PO(4) did not cause the endotoxin to form. An asporogenous mutant, B. thuringiensis subsp. kurstaki strain 290-1, produced delta-endotoxin on ST-a medium supplemented with 3 mM or more potassium but formed only poly-beta-hydroxybutyric acid granules on the media containing </=1 mM potassium. These results clearly indicate that a certain concentration of potassium is essential for the fermentative production of delta-endotoxin by these isolates of B. thuringiensis. Manganese could not be substituted for potassium. Phosphate ions stimulated poly-beta-hydroxybutyric acid formation by strain 290-1. The sporulation of B. thuringiensis and several other Bacillus strains was suppressed on the potassium-deficient ST medium. This suggests that potassium plays an essential role not only in Bacillus cell growth and delta-endotoxin formation but also in sporulation.

Journal Article↗
PubMed1982

Asporogenous Bacillus thuringiensis Mutant Producing High Yields of delta-Endotoxin.

An asporogenous Bacillus thuringiensis subsp. kurstaki strain IK mutant, strain 290-1, which produced high yields of delta-endotoxin, was obtained by ethyl methane sulfonate treatment of a spore suspension. The mutant strain produced about the same amount of delta-endotoxin as that produced by the parent strain, but 10 to 10 cells did not form any detectable dormant spores.

Journal Article↗
PubMed1982

A preferential isolation procedure for asporogenous Gram-positive bacteria.

A preferential isolation procedure was devised for asporogenous (Asp), Gram-positive (Gp), aerobic or facultative anaerobic bacteria which included the genera Arthrobacter, Corynebacterium, Brevibacterium, Microbacterium, Mycobacterium, and Micrococcus (Asp-Gp bacteria). An antibiotics-mixture agar which contained 5 to 10 micrograms per ml of colistin, 10 to 20 micrograms per ml of nalidixic acid and 30 micrograms per ml of cycloheximide was used in the isolation. Using this technique 47 Asp-Gp bacteria representing 26 subgroups of coryneform bacteria and Micrococcus were isolated from 3 soil samples. The method was far more efficient than the standard dilution-plate technique. This preferential method is available to isolate Asp-Gp bacteria from a sample containing about 500-fold more of other Gram-positive and negative bacteria.

Bacteria↗
PubMed1982

An enrichment isolation procedure for minor Bacillus populations.

In general, spores of B. cereus, B. megaterium, B. Sphaericus and B. subtilis strains germinated uniformly within a short time of incubation in a germination medium. In contrast, spores of B, circulans, B. brevis, B. laterosporus, B. pulvifaciens, B. polymyxa, B. pumilus, B. licheniformis and B. coagulans strains were usually slow and/or uneven germinators under the same conditions of incubation. The former group of Bacillus strains occur frequently in soils as the predominant population and the latter group of Bacillus species are found in many cases as minor populations. The minor populations of Bacillus were isolated with difficulty by the standard dilution-plate technique, but could easily be enriched by treating the soil sample in a germination medium for 2 to 3 hours at 30 to 35 degrees C, followed by heating it at 65 degrees C for 10 minutes ("minor-shifted isolation"). Using this technique, the minor Bacillus strains could be isolated from samples containing 100- to 1,000-fold more of the rapid germinators of Bacillus.

Bacillus↗
PubMed1982

A selective isolation procedure for Pseudomonas bacteria.

A selective isolation medium was devised for Pseudomonas bacteria. An antibiotic mixture which contained 10 micrograms per ml of cerexin A, 10 micrograms per ml of nalidixic acid and 30 micrograms per ml of cycloheximide was used. With the antibiotic medium, 58 strains of bacteria presumed to be Pseudomonas which were subdivided into 18 taxonomically different groups were isolated from 3 soil samples with 9% of contaminants. With this method, it was possible to isolate a Pseudomonas bacterium from a sample containing about 400 times as many other Gram-positive and -negative bacteria.

Anti-Bacterial Agents↗
PubMed1982

A selective isolation procedure for Micromonospora.

A selective medium containing 25 to 50 micrograms per ml of tunicamycin was devised to isolate micromonosporae from soil samples, making possible simple, preferential isolation of a variety of Micromonospora. When a large amount of Gram-negative bacteria was present in a sample, alkaline treatment (0.01 N NaOH, 5 approximately 10 minutes at 15 degrees C) wa employed to reduce the numbers. Using the tunicamycin agar medium, 1,585 strains of presumably different micromonosporae were obtained from 400 soil samples collected from various regions around the world. In average, 4 different Micromonospora strains could be located from one soil sample. This tunicamycin method made possible a concentrated screening method for new antibiotics from Micromonospora.

Bacteria↗
PubMed1980

Isolation of octapeptin D (studies on antibiotics from the genus Bacillus. XXVII).

A new peptide antibiotic complex, named octapeptin D, was isolated from culture broth of a microorganism belonging to the genus Bacillus. The trihydrochloride of the antibiotic was obtained as a colorless powder, soluble in water and methanol. The empirical formula, C47H88N12O11.3HCl.H2O, was indicated by elemental analysis. Amino acid analysis on the acid hydrolyzate demonstrated the presence of 2,4-diaminobutyric acid (4 moles), serine (1 mole) and leucine (3 moles). Gas chromatographic analysis with the methylated product of the ethereal extract of the acid hydrolyzate revealed the presence of beta-hydroxy isodecanoic acid, beta-hydroxy decanoic acid, beta-hydroxy isoundecanoic acid and beta-hydroxyanteisoundecanoic acid. Octapeptin D is active against Gram-negative and Gram-positive bacteria in vitro and in vivo.

Animals↗
PubMed1980

Hygromycin and epihygromycin from a bacterium, Corynebacterium equi No. 2841.

A newly isolated bacterium which produces antibacterial substances as below was taxonomically characterized and identified with Corynebacterium equi. The major antibiotic produced was determined to be hygromycin by direct comparison. The minor component, newly named epihygromycin was proved to be an epimer of hygromycin by spectrosocopic evidences and by chemical conversions. The presence of epihygromycin in the metabolites of Streptomyces noboritoensis (reported to be a hygromycin producer) was also observed.

Amino Acids↗
PubMed1977

Isolation of two new polymyxin group antibiotics. (Studies on antibiotics from the genus Bacillus. XX).

Two new members of polymyxin group antibiotics, polymyxins S1 and T1, were isolated from the culture broths of strains identified as Bacillus polymyxa Rs-6 and Bacillus polymyxa E-12, respectively. These antibiotics are strongly basic substances, their hydrochloric acid salts are soluble in water and methanol. They are primarily active against Gram-negative bacteria in vitro and in vivo though polymyxin T1 exhibits higher activities against Gram-positive bacteria than other polymyxin group antibiotics.

Bacillus↗
PubMed1976

A new antifungal antibiotic, trichostatin.

A new antibiotic, trichostatin, was isolated from the metabolites of strains of Streptomyces hygroscopicus. It is active against trichophytons and some fungi. The structure was determined to be a derivative of a primary hydroxamic acid by chemical and spectroscopic evidences.

Acetylation↗
PubMed1976

Isolation of three new antibiotics, thiocillins I, II and III, related to micrococcin P. Studies on antibiotics from the genus Bacillus. VIII.

Thiocillins I and II were isolated from the culture broth of Bacillus cereus G-15, and thiocillins II and III from that of Bacillus badius AR-91. Also, the former two were probably produced by Bacillus megatherium I-13. These antibiotics active against Gram-positive bacteria are soluble in a mixture of chloroform and methanol, show characteristic ultraviolet absorptions (maxima at ca. 275 nm and ca. 348 nm), and contain a high content of sulfur, as much as approximately 15%. They are related to each other and also to micrococcin P, but differentiated by chromatographic behaviours.

Animals↗
PubMed1976

Isolation of brevistin, a new peptide antibiotic. Studies on antibiotics from the genus Bacillus. IX.

A new peptide antibiotic, brevistin, was isolated from the culture broth of Bacillus brevis 342-14. Brevistin is an acylpeptide with an approximate empirical formula of C63H91N15O18 containing aspartic acid, threonine, glycine, valine, isoleucine, phenylalanine, tryptophan and 2,4-diaminobutyric acid. The antibiotic is soluble in acid and alkaline water. Its hydrochloride is soluble in methanol. Brevistin is active against Ggam-positive bacteria in vitro and in vivo, and is of low toxicity to mice.

Animals↗