Synthetic Studies on Colchicine-related Tropolones

Pschorr reaction of 4-[3-(3,4,5-trimethoxyphenyl)-propyl]-5-amino-tropolone (VII) gave desacetamidocolchiceine (IIa), though the oxidative coupling reaction of 4-[3-(3,4-dihydroxy- 5-methoxy phenyl)-propyl]-tropolone (Xa) failed to give the same compound (IIa).     

Chick embryo culture using duck egg shell--first successful hatch

The suitability of duck egg shell (DES) for chick embryo culture was investigated. Chick embryos were transferred into DESs with all egg contents after 3 days of normal incubation and cultured. The vessels made of polyethylene cling film were used for shell-less control. Among 35 embryos cultured in DESs, 21 survived until 16 days of incubation (13 days after transfer) and finally 3 newly hatched chicks were obtained at 22 days of incubation. One of them died 4 days later, but remaining two became full-grown cocks showing normal body weight and production of fertile sperms. Among 37 embryos cultured in polyethylene vessels, none survived over the period of 19 days of incubation. It is suggested that DES culture system may be useful for the various experiments using chick embryos.     

Sex-biased natal dispersal in Hokkaido brown bears revealed through mitochondrial DNA analysis

Understanding natal dispersal patterns is fundamental in the ecology and conservation biology of large wild carnivores. In this study, we used two approaches to determine genetic variation and dispersal patterns of brown bears in the Shiretoko Peninsula, eastern Hokkaido, Japan. The first approach was a large-scale genetic analysis. We analyzed haplotypes from the mitochondrial DNA (mtDNA) control region of 760 individual samples collected throughout the peninsula during 1998–2016. We detected seven haplotypes, including two that were confirmed for the first time. In females, the distribution of haplotypes was geographically structured, whereas haplotypes in males were distributed widely throughout the peninsula. Only some males in the lower peninsula had haplotypes that were not detected within the peninsula. The second approach was a local-scale genetic analysis, including intensive focal sampling in the Rusha area, a special wildlife protection area on the peninsula. Proportions of mtDNA haplotypes in adult bears were investigated and compared between the sexes. Although more than half of the females had the same haplotype, males had more diverse haplotypes, suggesting that they came to the Rusha area from other regions. Thus, our study revealed that mtDNA haplotype distribution has been maintained by female philopatry, and that bears exhibit male-biased dispersal. Furthermore, the lower peninsula appears to act as a contact zone between the peninsula and mainland Hokkaido, which is important for maintaining genetic diversity.     

Molecular marker to identify the fungus gnat, <Emphasis Type="Italic">Bradysia</Emphasis> sp. (Diptera: Sciaridae), a new pest of Welsh onion and carrot in Japan

A new pest of Welsh onion and carrot, the dark-winged fungus gnat, Bradysia sp., was found in the northern region of Saitama Prefecture, Japan. DNA sequences of mitochondrial cytochrome c oxidase subunit I revealed that Bradysia sp. is identical to the Chinese chive gnat, Bradysia odoriphaga Yang and Zhang. This suggests that Bradysia sp. may be an invasive species that originates from continental East Asia. Direct sequencing analysis and PCR using a species-specific primer were found to be useful tools for discriminating Bradysia sp. from other native Japanese fungus gnats, such as Bradysia impatiens (Johannsen), Pnyxia scabiei (Hopkins), and Lycoriella ingenua (Dufour).     

Lupin alkaloids from flowers of Echinosophora koreensis

(?)-Methyl 12-cytisineacetate (2) was isolated from methanol extracts of fresh flowers of Echinosophora koreensis together with seven known lupin alkaloids. Ethyl 12-cytisineacetate (3) was also isolated from ethanol extracts of the same flowers. Compounds 2 and 3 were artifacts and (?)-12-cytisineacetic acid (4) is assumed to be the principal source of 2 and 3. The variations in alkaloid content during growth of the flowers and the seedlings were also examined.     

On the three visual pigments in the retina of the firefly squid,Watasenia scintillans

Summary The deep-sea bioluminescent squid, Watasenia scintillans, has three visual pigments: The major one (A1 pigment) is based on retinal and has _max = 484 nm, the second one (A2 pigment) is based on 3-dehydroretinal and has _max = 500 nm, and the third one (A4 pigment) is based on 4-hydroxyretinal and has _max = 470 nm. The distribution of these 3 visual pigments in the retina was studied by HPLC analysis of the retinals in retina slices obtained by microdissection. It was found that A1 pigment was not located in the specific region of the ventral retina receiving the down-welling light which contains very long photoreceptor cells, forming two strata. A2 and A4 pigment were found exclusively in the proximal pinkish stratum and in the distal yellowish stratum. The role of these pigments in the retina is hypothesized to involve spectral discrimination. The extraction and analysis of retinoids to determine the origin of 3-dehydroretinal and 4-hydroxyretinal in the mature squid showed only a trace amount of 4-hydroxyretinol in the eggs. Similar analysis of other cephalopods collected near Japan showed the absence of A2 or A4 pigment in their eyes.Abbreviations HPLC high-performance liquid chromatography - IS inner segment - OS outer segment     

Far-infrared spectra of poly(-α-amino acids) with basic alkyl group side chains

Far-infrared spectra in the region from 700 to 60 cm^?1 have been measured for the α-helix structures of poly(L -α-amino-n-butyric acid), poly-L -norvaline, poly-L -norleucine, and poly-L -leucine and for the β-form structures of poly(L -α-amino-n-butyric acid), poly-L -valine, poly(DL -amino-n-butyric acid), poly-DL -norvaline, and poly-DL -norleucine. The changes of the spectra on N-deuteration have been measured in the region between 700 and 400 cm^?1. It is concluded that, the α-helix has characteristic bauds near 690, 650, 610, 380, 150, and 100 cm^?1, and that the β-form has characteristic bands near 700, 240, and 120 cm^?1. The main-chain vibrations in the region from 600 to 200 cm^?1 are strongly coupled with the side-chain deformation vibrations.     

Isolation and characterization of ornitho-kininogen

Ornitho-kininogen was purified from chicken blood plasma by a two-stage method using chromatography on columns of S-alkylated papain-Cellulofine and DEAE-5PW. The yield was 1.7 mg from 44 ml plasma. The isolated preparation gave a single band on sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS-PAGE) with or without 2-mercaptoethanol and on disc/polyacrylamide gel electrophoresis. The relative molecular mass, Mr, of ornitho-kininogen was estimated as 74,000 on SDS-PAGE using the Ferguson plot method. Ornitho-kininogen was found to have the similar properties to those of mammalian high-Mr kininogen, in terms of the amino acid composition, molecular mass, and susceptibility to plasma kallikrein. No kininogen corresponding to mammalian low-Mr kininogen and rat T-kininogen could be detected in chicken plasma. In fact, ornitho-kininogen was degraded rapidly by bovine plasma kallikrein, liberating a kinin. This kinin was isolated from the digest by reversed-phase HPLC. The primary structure of the isolated kinin was determined as Arg1-Pro2-Pro3-Gly4-Phe5-Thr6-Pro7-Leu8-Arg9. The sequence of this peptide, named ornitho-kinin, was similar to that of bradykinin except for the substitution of Thr6 and Leu8 for Ser6 and Phe8. The isolated ornitho-kinin induced a contraction of chicken smooth muscle and had a strong hypotensive effect in the chicken. However, it did not contract the isolated rat uterus. It is suggested that this specificity difference is due to the replacement of Phe8 by Leu8. The sequence of residues 1-30 of ornitho-kininogen exhibited 43% identity with that of bovine kininogen.