Parentage and host preference in the common cuckoo Cuculus canorus

Microsatellite DNA markers were used to investigate parentage relationships in a population of common cuckoo Cuculus canorus . Thirty adults and 55 nestlings were genotyped at six loci from blood samples collected over a four-year period. To test whether each cuckoo female specialises in parasitising one single host species (Host Preference Hypothesis), the maternal relationships were used to record each female's host choice. The results supported the Host Preference Hypothesis since no female (N=3) was recorded to have parasitised more than one of four congeneric host species breeding in the area. In contrast, the males (N=4) did not show such specialisation since two of them sired offspring reared by different host species.     

The braincase and palate of the tetrapodomorph sarcopterygian mandageria fairfaxi: morphological variability near the fish–tetrapod transition

The braincase of the Late Devonian tristichopterid sarcopterygian Mandageria fairfaxi , from Canowindra, NSW, Australia, differs radically from the conservative pattern present in other 'osteolepiforms' (stem–group tetrapodomorph fishes) and non–dipnoan sarcopterygian fishes in general. The basioccipital region is short, displaced anteriorly, and either unossified or loosely articulated to the exoccipital, leaving most or all of the notochordal tunnel open ventrally. The exoccipital complex, which is developed into a large saddle that would have rested on top of the notochord, carries large, triangular articular facets on its posterior face and appears to have formed part of a functional neck joint, a synovial articulation between the skull and vertebral column that allows the former to rotate against the latter. Such a joint is characteristic of post–Devonian tetrapods, but unknown in other sarcopterygians. We infer that the ventrally open notochordal tunnel allowed gentle flexion of the cranial notochord during (predominantly vertical) rotational movement at the occiput; this is a mechanically unique solution to the problem of creating a mobile neck. Other unusual features of Mandageria include a posteriorly located lateral commissure, and structures on the entopterygoid and lateral commissure that may have been associated with an elaborate spiracular tract.     

Inhibition of Cortisol Secretion by Dexamethasone in Relation to Body Fat Distribution: A Dose-Response Study

In this study, dexamethasone (dex) was administered in random order in doses of 0.05, 0.125, 0.25 and 0.5 mg at 10 p.m. with measurements of serum Cortisol in the morning (8 a.m.) of this and the following day. The test was performed on 22 apparently healthy men, 40 to 60 years of age, recruited from laboratory personnel, outpatient clinics or advertisements in a newspaper. Eight had a body mass index (BMI) (kg/m²) of <25 and 14 of >25. Twelve men had a waist hip ratio (WHR) of <1.0 and 10 men had a WHR of<1.0. Cortisol values at baseline were correlated inversely with WHR and were usually lower in men with a high (>1.0) rather than a low than low (<1.0) WHR after dex inhibition. There was apparently no inhibition by dex at 0.05 and 0.125 mg on average in men with a WHR of >1.0. In addition, the inhibition at 0.5 mg dex correlated negatively with the WHR and was significantly lower (p<0.05) in men with a WHR of >1.0 than in men with a WHR of <1.0. None of these differences or relationships was found to be dependent on BMI. It is concluded that men with an elevated WHR experience a decrease in the inhibition of Cortisol secretion by dex. It is suggested that this could explain or contribute to the elevated sensitivity of their HPA axis. Furthermore, lower morning Cortisol concentrations suggest a change in diurnal secretion patterns.     

Qualitative mathematical discussion of different evolutionary states in water transport systems of plants

We shall present several qualitative mathematical models to describe the early evolution of water transport systems in plants. To perform this in a systematic way we apply methods which have been developed in phenomenological synergetics. These methods rest on the fact that it becomes possible to describe the macroscopic behavior of a complex system by a set of control and order parameters when they are suitably identified. Our presentation is addressed to community with interdisciplinary interests.     

Fermenter production of an artificial fab fragment,rationally designed for the antigen cystatin,and its optimized crystallization through constant domain shuffling

The synthetic antibody model “M41” was rationally designed with a binding site complementary to chicken egg white cystatin as the prescribed antigen. In order to permit comparison between the computer model and an experimental three-dimensional structure of the artificial protein, its X-ray crystallographic analysis was pursued. For this purpose, M41 was expressed as a recombinant Fab fragment in E. coli by medium cell density fermentation employing the tightly regulated tetracycline promoter. The Fab fragment was efficiently purified via a His-6 tail fused to its heavy chain and immobilized metal affinity chromatography. To raise the chances for the productive formation of crystal packing contacts, three versions of the Fab fragment were generated with differing constant domains. One of these, the variant with murine C_K and C_H 1_γ1 domains, was successfully crystallized by microseeding in a sitting drop. The orthorhombic crystals exhibited symmetry of the space group P2₁2₁2₁ with unit cell dimensions a = 104.7 Å, b = 113.9 Å, c = 98.8 Å and diffracted X-rays to a nominal resolution of 2.5 Å. © 1995 Wiley-Liss, Inc.     

Land-use history of the Axlarp area in the Småland uplands,southern Sweden: palaeoecological and archaeological investigations

The results of pollen analysis, magnetic measurements (SIRM), and archaeological and historical investigations, in the Axlarp area are presented. With respect to natural conditions and the distribution of prehistoric features, this area is typical of the higher parts of the Småland uplands, which, agriculturally, is a marginal region of southern Sweden. The study shows that farming in the Axlarp area began at ca. 700 B.C. (dates in calibrated/calendar years). The period 700 B.C.-A.D. 500 was characterized by shifting cultivation of Hordeum and Triticum and much pasture. Between A.D. 500 and A.D. 1200 farming declined but some pasturage was still practised, possibly on a seasonal basis. Two farms were established in the Middle Ages, probably between A.D. 1200–1300. Cereals were sown in stone-cleared fields and pastoral farming and hay making was carried out. One farm was deserted during the 15th or early 16th century and the other developed into the hamlet Axlarp whose farmers practised a three-course cropping system. Land-use history as recorded in the pollen diagram can be related to activities associated with these farms. Cereals grown after A.D. 1200 included Hordeum and Avena, and possibly Triticum and Secale. There are no indications of slash-and-burn cultivation in the area.     

Social interactions in a group of free-ranging sows

Earlier studies on social behaviour in the domestic pig have only been performed on groups housed artificially. The present study was undertaken to investigate the social behaviour of free-ranging sows in a well-established flock, so that it could be compared with the behaviour of sows housed indoors that had been studied earlier. The free-ranging flock, which contained 13 animals, 5 of which were sows, lived in an enclosure, approximately 1.1 ha in area. The interaction sequences were registered during 1 h after feeding and during foraging in the enclosure. With sequence analysis, the effect of different behaviours on the behaviour of the receiver animal was measured. This allowed the behaviour patterns to be classed after function. “Aiming”, a behaviour pattern not previously seen, was interpreted as a threat behaviour, being “statistically strongly directive” towards submissive and flight behaviour. The functions of the other 7 behaviours included in the study were found to be the same as in the indoor groups studied earlier. The dominance order was not found to be better established than in the most extensively housed indoor group, but the level of aggression was very low, indicating that a stable dominance order does not automatically lead to a low level of aggression. It was found that the dominance order was mainly maintained through the behaviour of the subordinate animals, supporting the use of an “avoidance order” instead of an “aggression order” as a measurement of social dominance. On the whole, no dramatic differences were found between the behaviour of the free-ranging sows and that of the most extensively housed of the indoor groups studied earlier, although great differences were found between free-ranging sows and sows kept in confinement indoors.     

Complete remission in a patient with acute myelogenous leukemia treated with leukocyte α-interferon and cimetidine

Summary A 76-year-old woman with acute myelogenous leukemia with approximately 65% myeloblasts on bone marrow examination was treated daily with a combination of 4 megaU of leukocyte interferon IM and 1,000 mg cimetidine PO. During therapy there was a gradual decrease of bone marrow myeloblasts down to 9% and a normalization of peripheral white blood cells. The treatment was discontinued after 6 weeks because of increasing fatigue and anorexia. The general condition improved greatly during the following weeks and the patient entered complete remission, which has continued for 6 months so far. In the course of therapy there was a gradual appearance of antibodies showing a selective binding capacity to autochthonous leukemic cells with no tendency to increased binding to remission cells. The aim of this report is to stimulate a further evaluation of this form of therapy in additional AML patients whenever this might be justified as an alternative to conventional chemotherapy.     

Quantitative studies on brown algal phenols. I. Estimation of absolute polyphenol content of Ascophyllum nodosum (L.) Le Jol. and Fucus vesiculosus (L.)

Methods for estimating the absolute polyphenol content of the brown algae Ascophyllum nodosum (L.) Le Jol. and Fucus vesiculosus (L.) have been developed and tested. Polyphenols were extracted almost quantitatively from Ascophyllum nodosum using aqueous acetone, whereas this procedure was somewhat less efficient with Fucus vesiculosus. Colorimetric methods based on the Folin-Denis reagent, Brentamine Fast Red 2G Salt, and vanillin-H₂SO₄ were applied to acetone-free extracts for determination of polyphenol content relative to suitable reference compounds. Gravimetric methods based on hide powder and on haemoglobin were employed to derive ‘estimation factors’ (EFs) which allow calculation of the absolute polyphenol content from the relative polyphenol content. The values calculated for absolute polyphenol content are considered to be reasonably accurate, despite imprecisions in the methods and despite often large standard deviations, and re-emphasize the potential physiological and ecological significance of brown algal polyphenols. Although the precise EFs calculated here are not valid for other brown algae, the methods are considered to be generally applicable to other Phaeophyceae.     

ACTIVITY AND ISOENZYME PATTERN OF LACTATE DEHYDROGENASE IN ASTROBLASTS CULTURED FROM BRAINS OF NEWBORN MICE

Lactate dehydrogenase activity and isoenzyme distribution was determined in primary cultures of astroblasts as a function of the culture period. The specific activity increased during this period with a peak value (1.91 ± 0.18μmol x min^-1 x mg^-1 cell protein) after 2 weeks in culture. The isoenzyme pattern changed during 3 weeks in culture towards a higher proportion of the H₄ (LDH-1) isoenzyme which is analogous to the in vivo pattern. Omission of serum with or without dBcAMP (0.5 mM) in the culture medium during the third week of culture further enhanced this prominence of the H₄ isoenzyme. The specific activity (1.58 × 0.06 μmol x min^-1 x mg^-1 cell protein) of cultures grown in the presence of 0.5 mM-dBcAMP and absence of serum was close to the activity in the adult brain.