Volatiles from the epicuticular wax of watercress (Rorippa nasturtium-aquaticum)

Volatiles from the epicuticular wax of watercress were collected by ether washing and examined using gas chromatographic and mass spectrometric analysi     

Types of sesquiterpene-coumarin ethers from Achillea ochroleuca and Artemisia tripartita

In addition to known derivatives, four new sesquiterpene-coumarin ethers were isolated from the roots of Achillea ochroleuca and Artemisia tripartita and identified by ¹H and ¹³C NMR spectroscopy, including lanthanide induced shifts. The new compounds are isofraxidin derived ethers which differ from the previously described derivatives by ring cleavage and methyl migration within the terpenoid unit. The chemosystematic importance of sesquiterpene-coumarin ether accumulation within the two genera is briefly discussed.     

A new phage typing scheme forProteus mirabilis andProteus vulgaris strains

A new bacteriophage typing set, composed of 22 phages, was established as a tool for differentiation ofProteus strains. All the phages were tailed and included 4 morphological types (A1, A2, B1 and C1). They were classified into the familiesMyoviridae, Siphoviridae andPodoviridae. From the set, 19 phages had double-stranded DNA and 3 were single-stranded DNA phages.     

Crown alterations induced by decline: a study of relationships between growth rate and crown morphology in beech (Fagus sylvatica L.)

One of the first symptoms expressed by declining trees is reduced growth in stem diameter and length increment. The possibility of a relationship between length increment and crown thinning in beech (Fagus sylvatica L.) was investigated by developing a computer model to simulate first order branching patterns of the apical 2 m of monopodially branching beech trees, 70–100 years old, for a range of length increment rates. The model was based on values for branching angle, main axis and branch length increment, number of branches produced per year and branch mortality rates for six healthy and declining trees. Shoot growth rates in the apical 2 m of the sample trees ranged from about 5 cm/year (decline class 3) to 43 cm/ year (healthy). Simulations of branching patterns in the apical 2 m of trees growing at different rates indicated that, when growth rate exceeded about 20 cm/year, total first order branch length and area explored were independent of growth rate. When growth rates fell below this value there was a reduction in total area explored and first order branch length due primarily to the formation of fewer branches. More acute branching angles contributed to a reduction in the area explored. Growth rate-related crown thinning could increase the risk of bark necrosis and secondary pathogen infection during dry and/or hot spells.     

The anatomical relations of the ductus vomeronasalis and the occurrence of taste buds in the papilla palatina of Nycticebus coucang (primates, prosimiae) with remarks on strepsirrhinism.

Nycticebus coucang is typically strepsirrhine. This condition is basically the same in all prosimians except Tarsius. The rhinarium shows a labial part; the marked furrow in its median plane clefts the margin of the upper lip. The latter is attached to the gum between the median incisors by means of paired folds (not corresponding to a frenulum labii superioris). The labial cleft is continued in the sulcus papillae palatinae. The ductus vomeronasalis opens into the ductus nasoplatinus which, in turn, enters the aboral part of the sulcus palatinus. Thus strepsirrhinism provides, occasionally, an open communication of the olfactory systems (nose, vomeronasal organ) with the environment in front of the rhinarium. Strepsirrhine primates possess an internarium very similar to the one of platyrrhine monkeys. The shape of the nostrils is not characteristics for strepsirrhinism. A split-lip condition is likely ancestral to the complete lip condition, since it is found in several stems of mammals, especially in archaic forms. Strepsirrhinism, such as in lemuroid prosimians, is probably just one case of the primitive split-lip condition. Therefore, a median furrow in the external hairy skin of the upper lip, found in some platyrrhine monkeys, could be a rudiment of a cleft, indicating that a kind of a split lip condition was ancestral to the undivided lips of platyrrhine monkeys. Taste buds occur in the epithelium of the lateral surface of the papilla palatina of Nycticebus. Other lorisid prosimians have not been studied in this respect. The taste buds test water soluble substances entering the sulcus either way. These substances may come from the environment entering the sulcus through the labial cleft.     

Hemopoiesis stimulating and radioprotective effects of carboxymethylglucan.

Carboxymethylglucan, a novel soluble derivative of beta-1,3-glucan, was found to enhance hemopoietic recovery in sublethally gamma-irradiated mice and to increase survival in lethally irradiated animals when given 24 hours prior to irradiation. Postirradiation treatment with carboxymethylglucan also induced favourable effects in terms of survival when used in combination with preirradiation cystamine administration.     

Characterization of the human cyclophilin gene and of related processed pseudogenes

The human cyclophilin gene was isolated from a genomic library derived from leucocyte DNA and sequenced. The gene contains five exons and four introns. The amino acid sequence deduced from the exons matches perfectly the one previously determined from the T-cell cyclophilin cDNA. A TATA box is visible in the promoter region and putative Sp1 binding sites are also found there as well as in the first intron. Six members of the middle repetitive Alu gene family are present in one or other orientation in the non-coding regions of the cyclophilin gene. Hybridisation of genomic DNA to probes derived from the promoter region or the first intron indicates that the cyclophilin gene is present as a single copy in the human haploid genome. Seven other cyclophilin-related DNA clones isolated from the same library were also characterized. They show a high degree of similarity to the cyclophilin cDNA and are colinear to it. However, multiple genetic lesions, often including deletion and/or insertion events which modify the reading frame, are found in these clones which are therefore likely to represent processed pseudogenes.     

Interaction of a phosphorylated site of muscle phosphofructokinase with the activation of the enzyme by NH4+ and K+.1

The crystal structure of the cyclic peptide disulfide

has been determined by X-ray diffraction. The peptide crystallizes in the space group P2₁2₁2₁, with a = 8.646(1), b = 18.462(2), c = 19.678(3)Å and Z = 4. The molecules adopt a highly folded compact conformation, stabilized by two intramolecular 4→ 1 hydrogen bonds between the Cys (1) and Pro (2) CO groups and the Cys (4) and methylamide NH groups, respectively. The backbone conformational angles for the peptide lie very close to those expected for a 3₁₀ helix. The S-S bridge adopts a right handed twist with a dihedral angle of 82°. The structure illustrates the role of stereochemically constrained residues, in generating novel peptide conformations.     

Genetic analysis of transpositions in the lac region of Escherichia coli

The lac region of Escherichia coli, carried on an F′ lacproB episome, was used as a target for the transposition of several transposable elements. Tn9 shows a preferential integration (by a factor of 50) into a region extending from the end of the Z gene through the Y gene. Throughout the remainder of the lacI, Z and Y genes one other short region, located in the middle of the I gene, is favored for integration. Within these favored regions many different integration points are evident. Inspection of the DNA sequence for the I and Y genes, and parts of the Z gene, shows a strong correlation between A + T richness and regions of preferential integration. Tn5 insertions follow a similar pattern, although with less preference; whereas Tn10 insertions (provided by T. J. Foster), also favor the Y gene and the end of Z, but are distributed among fewer integration points. Most of the Tn3 insertions into the episome are accompanied by a nearby or adjacent deletion.