10-nonacosanol,sitosterol and nonacosanediols in Juniperus pinchotii

GC of juniper leaf non-saponifiables gave three peaks of sterol-triterpenes which were identified as 10-nonacosanol, sitosterol and a mixture of nonacosanediols.     

Population relationships of Simulium yahense and Simulium sanctipauli in the Firestone Rubber Plantation at Harbel, Liberia

Comparative genetic differences for the phosphoglucomutase and trehalase loci were surveyed in larval and adult blackfly populations of the onchocerciasis vectors Simulium yahense Vajime and Dunbar, and S.sanctipauli Vajime and Dunbar. Genotype frequencies for each stage and all populations were at Hardy-Weinberg equilibrium, indicating that S.yahense and S.sanctipauli remain genetically distinct. S.yahense populations from three different locations were found to be genotypically comparable. The larval population of S.yahense found in closest proximity to a S.sanctipauli population was found to express the phosphoglucomutase allele 1.33, characteristic of S.sanctipauli, with significantly greater frequency than other larval populations of S.yahense. This may constitute evidence of limited genetic introgression of S.sanctipauli with the S.yahense population.     

Focal contacts of spreading platelets with the substratum

Contacts with glass substratum formed by the spreading rabbit platelets were examined by an antibody-exclusion method; monoclonal antibodies against 80 kD bovine serum protein were used. It was found that platelets form focal contacts in the course of spreading. The size of the largest focal contacts formed by platelets is smaller than that of the contacts formed by fibroblasts. The antibody-exclusion method revealed focal contacts of platelets much more clearly than interference reflection microscopy (IRM). The similarity of reactions involved in spreading platelets and of large nucleus-containing tissue cells is discussed.     

Comparative study on the surface ultrastructures of fertilized eggs of three Sebastes species

Fertilized eggs of Sebastes schlegelii, Sebastes pachycephalus and Sebastes hubbsi are morphologically similar under stereomicroscope. However, under the scanning electron microscope, significant differences in the ultrastructures of the egg surface among the three species were observed, and herein, a taxonomic key was proposed for future applications. A clustering analysis based on the ultrastructures of the egg surface and the diameter of the oil globule suggested that among the three species, S. hubbsi and S. pachycephalus were more genetically similar, while S. schlegelii had diverged earlier. The results agree with the conclusions drawn from morphological and molecular analyses on adult samples of the same species.     

Seasonal and annual variability in the phytoplankton community of the Raunefjord,west coast of Norway from 2001–2006

Changes in phytoplankton community composition potentially affect the entire marine food web. Because of seasonal cycles and inter-annual variations in species composition, long-term monitoring, covering many sequential years, is required to establish a baseline study and to reveal long-term trends. The current study describes the phytoplankton biomass variations and species composition in relation to hydrographic and meteorological conditions in the Raunefjord, western Norway, over a 6-year period from 2001 to 2006. The extent of inflow or upwelling in the fjord varied from year to year and resulted in pronounced differences in water column stability. The annual phytoplankton community succession showed some repeated seasonal patterns, but also high variability between years. Two to four diatom blooms were observed per year, and the spring blooms occurring before water column stratification in March were dominated by Skeletonema marinoi and Chaetoceros socialis, and other Chaetoceros and Thalassiosira spp. Blooms of the haptophytes Phaeocystis pouchetii and Emiliania huxleyi were irregular and in some years totally absent. Although E. huxleyi was present all year round it appeared in bloom concentrations only in 2003, when the summer was warm and the water column characterized by high surface temperatures and pronounced stratification. The annual average abundance of both diatoms and flagellates increased during the six years. Despite the high variation from year to year, our investigation provides valuable knowledge about annual phytoplankton community patterns in the region, and can be used as a reference to detect possible future changes.     

Melanogenesis‐Inhibitory and Cytotoxic Activities of Chemical Constituents from the Leaves of Sauropus androgynus L. Merr. (Euphorbiaceae)

A new steroid, 20‐hydroxyisofucosterol (stigmasta‐5,24(28)‐diene‐3β,20β‐diol) ( 7 ), along with six known compounds 1 – 6 were isolated from the MeOH extract of the leaves of Sauropus androgynus L. Merr . (Euphorbiaceae). The structure of new steroid was determined by HR‐APCI‐MS and various NMR techniques in combination with literature data. Subsequently, their anti‐inflammatory, cytotoxic activities against five human cell lines, as well as inhibitory activities against the α‐MSH induced melanogenesis on the B16 cell line were evaluated. As the results, steroid compounds, 6 and 7 exhibited moderate cytotoxic to HL60, AZ521, SKBR3, and A549 tumor cell lines (IC₅₀ 26.9 – 45.1 μm ) with high tumor selectivity for A549 relative to WI38 cell lines (SI 2.6 and 3.0, resp.). And, flavonoid compounds, 4 and 5 exhibited superior inhibitory activities against melanogenesis (67.0 – 94.7% melanin content), even with no or low toxicity to the cells (90.1 – 99.6% cell viability) at the concentrations from 10 to 100 μm . Furthermore, Western blot analysis suggested that compound 5 could inhibit melanogenesis by suppressing the protein expressions of MITF, TRP‐1, TRP‐2, and tyrosinase.     

A small RNA that complements mutants in the RNA processing enzyme ribonuclease P

Four temperature-sensitive RNase P mutants were analyzed for the accumulation of 10 S RNA. In the 10 S region of the polyacrylamide gel two molecules appear, a and b. While the level of 10 Sa seems to be affected in some of the mutants, the 10 Sb molecule was not found in rnpB mutants. A plasmid (pL2), which contains Escherichia coli DNA sequences that complement, at least partially, rnp mutations, directs the synthesis of 10 Sb RNA. The presence of the pL2 plasmid complements the rnpA49, rnpB3187 and the rnpC241 mutations, as revealed by colony formation at “non-permissive” temperatures. However, the complementation of the rnpA49 mutation is much better than that of the other mutations. The complementation can also be measured by the increased level of RNase P activity in extracts. 10 Sa and b RNAs are unique among all RNAs tested thus far, since they are stable during exponential growth at 30 °C and 37 °C. However, at higher temperatures, such as 43 °C, the molecules are somewhat less stable, and they become rather labile when RNA synthesis is blocked by rifampicin. Structural analysis revealed that the 10 Sa and 10 Sb RNA molecules have dissimilar sequences.     

Isolation and characterization of proteinase inhibitor I from etiolated tobacco leaves

Proteinase Inhibitor I was induced to accumulate in tobacco (Nicotiana tabaccum) leaves by placing plants in darkness for 10 days at 27 degrees C. The inhibitor was isolated using ammonium sulfate precipitation, Sephadex G-75 chromatography, heating, and affinity chromatography with a chymotrypsin-Sepharose column. Inhibitor I was purified 232-fold with a yield of 34 mg from 2.5 kg of leaves. Affinity-purified tobacco Inhibitor I was shown to be homogeneous by gel electrophoresis in both nondissociating and dissociating buffers. The inhibitor has a molecular weight of 39,000 +/- 1000 determined by gel filtration and, like its potato and tomato counterparts, is composed of five subunits of molecular weight 8100. The tobacco Inhibitor I strongly inhibits chymotrypsin and weakly inhibits trypsin. The chemical, physical, and immunological properties of tobacco Inhibitor I indicate that it is structurally very similar to potato tuber Inhibitor I and tomato leaf Inhibitor I, although the synthesis and accumulation of the three inhibitors in their respective tissues are all under different developmental or environmental regulation.     

Periodate oxidation studies in the elucidation of the structures of sialic acid containing oligosaccharides

The structures of sialo-oligosaccharide alditols as determined by ¹H-NMR spectrometry together with methylation analysis did not correspond with those derived previously from quantitative periodate oxidation data alone. Possible causes of the discrepancy were explored in the periodate oxidation methodology. No free sialic acid was released by the acidity of the periodate in the course of oxidation at pH 4.5. The anionic properties of the sialic acid residues were therefore utilized to separate the periodate oxidation products and thereby establish the position of the sialic acid in the oligosaccharide chain.