Morphologische Unterscheidungsmerkmale zwischen Wolfs-(Canis lupus L.) und Hundeschädel (Canis familiaris L.)

European Journal of Wildlife Research - Durch Vergleich von 145 Wolfsschädeln mit 165 Schädeln großer Hunde fand der Verfasser sieben Merkmale am Schädel und ein Merkmal am...     

The Involvement of Indole-3-Acetic Acid Produced by Bradyrhizobium elkanii in Nodule Formation

IAA-deficient mutants T10, T27 and TN3 were isolated from B.elkanii USDA 31 by spontaneous and/or N-methyl-N'-nitro-N-nitrosoguanidine(NTG) mutageneses. Inoculation with these mutants significantlyreduced the nodule number on soybean roots when compared tothat of the parent strain. Furthermore, exogenous IAA applicationrestored the nodule number of soybeans inoculated with TN3 tothe original level. (Received July 18, 1994; Accepted September 13, 1994)     

Validity of a self-administered food frequency questionnaire in the assessment of heterocyclic amine intake using 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) levels in hair

Several case-control studies have reported possible associations between heterocyclic amine (HCA) intake and the risk of cancer. The validity of questionnaires used to assess HCA intake has hardly been examined, however; in particular, no biomarker able to serve as an independent measure of habitual HCA intake has been established. In this study, we examined the validity of HCA intake estimated from a food frequency questionnaire (FFQ) using 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) level in hair as a reference method. Study subjects were 20 volunteers (7 men and 13 women) aged 25–57 years residing in Tokyo or neighboring cities in Japan. The subjects completed the FFQ, and gave 3–5 g of hair twice at an interval of 1–3 months for use in establishing validity. Results showed that intakes of PhIP, MeIQ, Trp-P-1, and total HCA by the FFQ were significantly correlated with PhIP levels in hair when adjustment was made for melanin content (r = 0.47, r = 0.50, r = 0.55, and r = 0.51, respectively). The present study indicates that HCA intake estimated from this FFQ provides a reasonable ranking of individuals to allow the analysis of associations between HCA intake and risk of cancer in large-scale epidemiological studies.     

A simple rapid separation of C1-esterase using an immunoadsorbent column.

An immunoadsorbent-antibody (egg albumin-Sepharose-antibody) column was found to be suitable for the rapid separation of C1-esterase from normal human serum. About 1.54 mg of C1-esterase, with a specific activity of 447 units/mg was obtained in voer 80% yield from the 20 ml of human serum.     

Phylogeography of a salmonid fish,masu salmon Oncorhynchus masou subspecies-complex,with disjunct distributions across the temperate northern Pacific

1. Climate oscillations during the Pleistocene had profound effects on the evolutionary history of freshwater fishes now distributed across northern temperate regions. The extent of continental glaciation on the western side of the North Pacific, including areas of East Asia, was more limited as compared with regions of North America, Europe and high-latitude areas of the North Pacific. Therefore, the effects of climate oscillations might have influenced species in dissimilar ways depending on the species' distribution.
2. We used mitochondrial DNA (mtDNA) and microsatellite DNA (msDNA) markers to clarify the evolutionary history of masu salmon Oncorhynchus masou subspecies-complex (family Salmonidae) distributed in historically non-glaciated regions in the western North Pacific.
3. No marked regional or subspecies-specific mtDNA haplotype associations were recognised, except for O. masou subsp., a lacustrine form endemic to Lake Biwa, an ancient lake in central Honshu. The landlocked subspecies O. masou formosanus, with a disjunct distribution on Taiwan Island, exhibited no diagnostic population features differing from the other subspecies, in either mtDNA or msDNA markers. Mismatch distribution and Bayesian skyline plot analyses indicated relatively recent range expansion and rapid population growth for masu salmon during the last glacial period (c. 0.1–0.15 Ma).
4. Contrary to the mtDNA genealogy, Bayesian clustering using msDNA showed two main genetic clusters, mainly northern populations of the subspecies O. m. masou and populations of the subspecies O. m. ishikawae in southern areas of the Japanese Archipelago. Notably, O. m. formosanus on Taiwan Island was included in the O. m. masou group, and O. masou subsp. was included in the O. m. ishikawae group.
5. Our results suggest that the masu salmon subspecies-complex in historically non-glaciated regions of the Temperate Northern Pacific is characterised by weak population structuring and shallow genetic differentiation among the subspecies, except for O. masou subsp. owing to its long isolation in Lake Biwa. Incomplete lineage sorting and historical inter-subspecies hybridisation, possibly due to secondary contact, seem to be plausible explanations for discrepancies in the mitochondrial DNA genealogy and nuclear DNA genetic structure.