Solid phase fluoroimmunoassay for 11-deoxycortisol in serum using 21-amino-17-hydroxyprogesterone

Solid phase fluoroimmunoassay of serum 11-deoxycortisol (17,21-dihydroxy-4-pregnene-3,20-dione) was established using fluorescein isothiocyanate-labelled 11-deoxycortisol and anti-11-deoxycortisol antibody-conjugated polyacrylamide beads. 21-Amino-17-hydroxyprogesterone (21-amino-17-hydroxy-4-pregnene-3,20-dione) was synthesized as a useful derivative for preparing the fluorescent dye conjugate. Serum 11-deoxycortisol was measured with this assay system after extraction and purification by Sephadex LH-20 column chromatography. The minimal amount of 11-deoxycortisol detected was 40 pg/tube and the measurable range was from 0.04 to 5.0 microgram/dl. Intra- and inter-assay coefficients of variation were 8.3% (n=6) and 9.8% (n=5), respectively. 11-deoxycortisol values determined by the present assay correlated well with those determined by radioimmunoassay. The present assay is particularly suitable for estimating the conditions of the pituitary and adrenocortical functions.     

Scanning electron-microscopy of starch granules, with or without amylase attack

Scanning electron-microscopy (SEM) revealed that, for starch granules relatively susceptible to amylase, numerous pin holes could be observed on the surfaces of granules attacked by amylase. We also observed that the pores penetrated into the inner layers of granules during the enzyme action and some of the granules exhibited a terraced or step-shaped apperance in their inner portions. These internal characteristics are most probably indicative of layered internal structures of the granules. The other characteristic observations by SEM were striated structures on the surfaces of starch granules of banana, lily, and lotus attacked by pancreatin.     

Modulation of glycosaminoglycan synthesis during cell growth as observed in an embryonic chick tendon cell culture

Glycosaminoglycan synthesis during cell growth has been studied in terms of unit cell numbers, using 16-day-old embryonic chick tendon cell cultures. Hyaluronic acid production was found to be inversely proportional to the cell density, while the levels of sulfated-glycosaminoglycan synthesis remained constant. On the other hand, hyaluronic acid production remained constant during cell proliferation, though chondroitin sulfate synthesis increased rapidly during an actively growing phase of the cultured cells, and dermatan sulfate and heparan sulfate syntheses increased gradually.     

Stereospecificity for oligosaccharides of two receptor sites in a labellar sugar receptor of the fleshfly.

Responses of a single sugar receptor to oligosaccharides, such as turanose, palatinose, cellobiose, trehalose, maltotriose, melezitose, and raffinose, were depressed almost completely after 3 min treatment with 0·5 mM p-chloromercuribenzoate (PCMB). In the same preparation, responses to d-glucose were depressed in the same manner, but those to d-fructose were hardly affected after PCMB treatment. This may indicate that these oligosaccharides do not react with a furanose site but react only with a pyranose site. The stereospecificity for these oligosaccharides of the sugar receptor are discussed.The response to 4 M d-mannose, a very weak stimulative sugar, was almost completely depressed after PCMB treatment, which suggests that a stimulative fraction of d-mannose reacts with the pyranose site in spite of its inhibitory effect on fructose stimulation.     

The alpha 2(VIII) collagen gene. A novel member of the short chain collagen family located on the human chromosome 1

Type VIII collagen is a major component of Descemet's membrane, the specialized basement membrane of corneal endothelial cells. Sequence analysis of a cDNA isolated from a library made with mRNA from rabbit corneal endothelial cells has indicated that type VIII molecules contain a polypeptide chain, alpha 1(VIII), consisting of a short triple-helical domain of 454 amino acid residues flanked by non-triple-helical domains of 117 and 173 amino acid residues at the amino and carboxyl ends, respectively (Yamaguchi, N., Benya, P. D., van der Rest, M., and Ninomiya, Y. (1989) J. Biol. Chem. 264, 16022-16029). The sequence of alpha 1(VIII) is strikingly similar to that of alpha 1(X) collagen, a product of hypertrophic chondrocytes. Also, characterization of the alpha 1(VIII) and alpha 1(X) collagen genes has shown that they are quite similar in their exon organization. It has been concluded, therefore, that they are homologous members of a distinct subclass of collagen genes (Yamaguchi, N., Mayne, R., and Ninomiya, Y. (1991) J. Biol. Chem. 266, 4508-4513). We have given this subclass the name short chain collagens because of the relatively small size of the triple-helical domain. In the present study, we report on the identification and characterization of a collagen gene encoding a polypeptide which is co-expressed with the alpha 1(VIII) chain in corneal endothelial cells. This collagen chain contains a triple-helical and a carboxyl non-triple-helical domain encoded by a single, large exon both in mice and humans. We conclude, therefore, that the genes encodes a novel member of the short chain collagen family, and we have given this chain the designation alpha 2(VIII) collagen. By in situ hybridization we demonstrate that the alpha 2(VIII) gene is located in the p32.3-p34.3 region of the short arm of chromosome 1.     

The Incidence of R Factors in Bordetella bronchiseptica Isolated from Pigs

Bordetella bronchiseptica strains isolated from the nasal cavities of young pigs in Japan from 1969 to 1972 were surveyed for drug resistance and distribution of R factors. Of 304 strains examined, 71 (23%) were resistant to either one or more of following three drugs, streptomycin (SM), sulfadimethoxine (SA), and aminobenzyl penicillin (APC). Triple (SM.SA.APC)-resistance was most frequent among these resistant strains. Strains of double (SM. SA)- or single (SM)- and (SA)-resistance were also isolated, but were very few in numbers. Of the 71 drug-resistant strains, 61 (86%) were found to carry R factors which were capable of conjugal transfer. All of these R factors had the triple (SM.SA.APC)-resistant markers and were identified as fi^– (no fertility inhibition) type. The (SM.SA.APC)-resistant strains carrying R factors had been isolated from pigs reared on various farms in different districts, and consequently the prevalence of B. bronchiseptica strains carrying R factors was considered to be relatively wide-spread in young pigs.     

Mycobiont diversity and first evidence of mixotrophy associated with Psathyrellaceae fungi in the chlorophyllous orchid Cremastra variabilis

Mixotrophy (MX, also called partial mycoheterotrophy) in plants is characterized by isotopic abundances that differ from those of autotrophs. Previous studies have evaluated mycoheterotrophy in MX plants associated with fungi of similar ecological characteristics, but little is known about the differences in the relative abundances of ¹³C and ¹⁵N in an orchid species that associates with several different mycobionts species. Since the chlorophyllous orchid Cremastra variabilis Nakai associates with various fungi with different ecologies, we hypothesized that it may change its relative abundances of ¹³C and ¹⁵N depending on the associated mycobionts. We investigated mycobiont diversity in the chlorophyllous orchid C. variabilis together with the relative abundance of ¹³C and ¹⁵N and morphological underground differentiation (presence or absence of a mycorhizome with fungal colonization). Rhizoctonias (Tulasnellaceae, Ceratobasidiaceae, Sebacinales) were detected as the main mycobionts. High differences in δ¹³C values (– 34.7? to?– 27.4 ‰) among individuals were found, in which the individuals associated with specific Psathyrellaceae showed significantly high relative abundance of ¹³C. In addition, Psathyrellaceae fungi were always detected on individuals with mycorhizomes. In the present study, MX orchid association with non-rhizoctonia saprobic fungi was confirmed, and the influence of mycobionts on morphological development and on relative abundance of ¹³C and ¹⁵N was discovered. Cremastra variabilis may increase opportunities to gain nutrients from diverse partners, in a bet-hedging plasticity that allows colonization of various environmental conditions.

     

New Strategies for the Chemical Synthesis of Biologically Important Nucleic Acid Derivatives

Abstract

This paper describes general methods for the synthesis of N-phosphorylated ribonucleosides and oligonucleotides containing a 2′-O-phosphorylated or 2′-O-thiophosphorylated ribonucleoside. The NMR-based conformational analysis and computational molecular dynamics simulation of the 2′-O-phosphorylated ribonucleoside residue in such modified oligonucleotides suggested that the ribose residue existed preferentially in a C2′-endo conformation. It was also found that simple heating of 2′-O-phosphorylated oligonucleotides resulted in rapid dethiophosphorylation.     

High mycorrhizal specificity in the mycoheterotrophic Burmannia nepalensis and B. itoana (Burmanniaceae)

Mycorrhizal fungi of mycoheterotrophic Burmannia nepalensis and B. itoana were identified by molecular identification methods based on fungal SSU nrDNA region. In B. nepalensis, RFLP patterns and sequences from all root samples from 14 individuals were identical. A single fungal sequence was also obtained from B. itoana roots from three individuals. Phylogenetic analysis showed that the fungal sequences from these two species are included in Glomeraceae (former Glomus group A). Our results indicate that the two Burmannia species are associated with narrow phylogenetic ranges of arbuscular mycorrhizal fungi.