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In collections of ectoparasites from 368 small ground finches, Geospiza fuliginosa, in populations from the islands of Isabela, Santa Cruz, San Cristóbal, and Santa Fé, in the Galápagos Archipelago, Ecuador, we found 8 species of mites. Four mite species were common on all islands sampled, i.e., Mesalgoides geospizae Mironov and Pérez (Psoroptoididae), Xolalges palmai Mironov and Pérez (Xolalgidae), and 2 new species, Trouessartia geospiza n. sp. (Trouessartiidae) and Proctophyllodes darwini n. sp. (Proctophyllodidae). Four other species were represented by single collections from G. fuliginosa, i.e., Pterodectes atyeoi n. sp. (Proctophyllodidae), Strelkoviacarus sp. (Analgidae), Dermoglyphus sp. (Dermoglyphidae), and Dermanyssus sp. (Dermanyssidae). Authorship of new species names is attributed to the 3 authors who prepared the descriptions (B.M.O.C., J.F., D.L.). Trouessartia geospiza and P. atyeoi were also found on previously collected specimens of other Geospiza species in museum collections. For the 4 common species, we found no differences in prevalence among the 4 island populations, but infection prevalence differed among the 4 species. The mean infection prevalence was high for T. geospizae (89%), moderate for M. geospizae (58%) and X. palmai (44%), and low for P. darwini (26%) in all populations. The feather mite fauna of G. fuliginosa was similar to that of other Geospiza species, and generally related to communities found on other emberizid finches.

Hypoxic-ischemic encephalopathy (HIE) is graded with three levels of severity-mild, moderate and severe. The outcome of individuals with mild and severe grades can be reliably predicted from this scheme. Individuals with moderate degree are divided in outcome between those who suffer major neurologic problems (e.g., cerebral palsy) and those who are assumed to recover from the incident. It is however not clear if the recovery is complete and unquestionable. A group of adolescents who had been born at term, diagnosed with moderate HIE but had not developed cerebral palsy, were investigated with diffusion tensor imaging. Fractional anisotropy maps were used as a basis of comparison to a group of controls of the same age and gender distribution. In several white matter areas fractional anisotrophy was lower in the group of individuals with a history of moderate HIE. These areas include the internal capsules (bilaterally in the posterior limb and on the right in the anterior limb), the posterior and anterior corpus callosum as well as frontal inferior white matter areas. These results indicate that even in the absence of such major neurologic impairments as cerebral palsy, moderate HIE causes long term white matter disturbances which are not repaired by adolescence.

Kin selection is a powerful tool for understanding cooperation among individuals, yet its role as the sole explanation of cooperative societies has recently been challenged on empirical grounds. These studies suggest that direct benefits of cooperation are often overlooked, and that partner choice may be a widespread mechanism of cooperation. Female eider ducks (Somateria mollissima) may rear broods alone, or they may pool their broods and share brood-rearing. Females are philopatric, and it has been suggested that colonies may largely consist of related females, which could promote interactions among relatives. Alternatively, shared brood care could be random with respect to relatedness, either because brood amalgamations are accidental and nonadaptive, or through group augmentation, assuming that the fitness of all group members increases with group size. We tested these alternatives by measuring the relatedness of co-tending eider females in enduring coalitions with microsatellite markers. Females formed enduring brood-rearing coalitions with each other at random with respect to relatedness. However, based on previous data, partner choice is nonrandom and dependent on female body condition. We discuss potential mechanisms underlying eider communal brood-rearing decisions, which may be driven by the specific ecological conditions under which sociality has evolved in this species.

Aim: To evaluate children born post-term (gestational age>or=42 weeks) with respect to developmental data obtained at the ages of 4 and 5.5 y., Methods: The study population included all children (n=354) born in 1991 at Huddinge University Hospital with a gestational age of >or=42 wk. The births were identified and perinatal data were collected through the Swedish National Birth Registry. Developmental assessments from the child health centres were analysed. Children born at term, but before a gestational age of 42 wk, served as controls. Logistic regression analysis was used to analyse the data., Results: Children born post-term had more developmental deviations than the controls (estimated odds ratio 2.20; 95% CI: 1.29-3.85). Boys had more deviations than girls (estimated odds ratio 1.92; 95% CI: 1.11-3.45)., Conclusion: Our results indicate that there might be an association between post-term birth and developmental deviations.

The longitudinal movement of blood vessel walls has so far gained little or no attention, as it has been presumed that these movements are of a negligible magnitude. However, modern high-resolution ultrasound scanners can demonstrate that the inner layers of the arterial wall exhibit considerable movements in the longitudinal direction. This paper evaluates a new, noninvasive, echo-tracking technique, which simultaneously can track both the radial and the longitudinal movements of the arterial wall with high resolution in vivo. Initially, the method is evaluated in vitro using a specially designed ultrasound phantom, which is attached to and moved by an X-Y system, the movement of which was compared with two high-resolution triangulation lasers. The results show an inaccuracy of 2.5% full scale deflection (fsd), reproducibility of 12 microm and a resolution of 5 microm, which should be more than sufficient for in vivo studies. The ability of the method is also demonstrated in a limited in vivo study in which a preselected part of the inner vessel wall of the right common carotid artery of a healthy volunteer is tracked in two dimensions over many cardiac cycles. The results show well reproducible x-y movement loops in which the recorded radial and longitudinal movements both are of the magnitude millimetre.

The genetic diversity within 195 rhizobial strains isolated from root nodules of 18 agroforestry species (15 woody and three herbaceous legumes) growing in diverse ecoclimatic zones in southern Ethiopia was investigated by using PCR-RFLP of the ribosomal operon [16S rRNA gene, 23S rRNA gene and the internal transcribed spacer (ITS) region between the 16S rRNA and 23S rRNA genes] and 16S rRNA gene partial sequence (800 and 1350 bp) analyses. All of the isolates and the 28 reference strains could be differentiated by using these methods. The size of the ITS varied among test strains (500-1300 bp), and 58 strains contained double copies. UPGMA dendrograms generated from cluster analyses of the 16S and 23S rRNA gene PCR-RFLP data were in good agreement, and the combined distance matrices delineated 87 genotypes, indicating considerable genetic diversity among the isolates. Furthermore, partial sequence analysis of 67 representative strains revealed 46 16S rRNA gene sequence types, among which 12 were 100% similar to those of previously described species and 34 were novel sequences with 94-99% similarity to those of recognized species. The phylogenetic analyses suggested that strains indigenous to Ethiopia belonged to the genera Agrobacterium, Bradyrhizobium, Mesorhizobium, Methylobacterium, Rhizobium and Sinorhizobium. Many of the rhizobia isolated from previously uninvestigated indigenous woody legumes had novel 16S rRNA gene sequences and were phylogenetically diverse. This study clearly shows that the characterization of symbionts of unexplored legumes growing in previously unexplored biogeographical areas will reveal additional diversity.

Following a brief review of the development of medical ultrasonics from the mid-1930s to the mid-1950s, the collaboration between Edler and Hertz that began in Lund in 1953 is described. Using an industrial ultrasonic flaw detector, they obtained time-varying echoes transcutaneously from within the heart. The first clinical applications of M-mode echocardiography were concerned with the assessment of the mitral valve from the shapes of the corresponding waveforms. Subsequently, the various M-mode recordings were related to their anatomical origins. The method then became established as a diagnostic tool and was taken up by investigators outside Lund, initially in China, Germany, Japan and the USA and, subsequently, world-wide. The diffusion of echocardiography into clinical practice depended on the timely commercial availability of suitable equipment. The discovery of contrast echocardiography in the late 1960s further validated the technique and extended the range of applications. Two-dimensional echocardiography was first demonstrated in the late 1950s, with real-time mechanical systems and, in the early 1960s, with intracardiac probes. Transesophageal echocardiography followed, in the late 1960s. Stop-action two-dimensional echocardiography enjoyed a brief vogue in the early 1970s. It was, however, the demonstration by Bom in Rotterdam of real-time two-dimensional echocardiography using a linear transducer array that revolutionized and popularized the subject. Then, the phased array sector scanner, which had been demonstrated in the late 1960s by Somer in Utrecht, was applied to cardiac studies from the mid-1970s onwards. Satomura had demonstrated the use of the ultrasonic Doppler effect to detect tissue motion in Osaka in the mid-1950s and the technique was soon afterwards applied in the heart, often in combination with M-mode recording. The development of the pulsed Doppler method in the late 1960s opened up new opportunities for clinical innovation. The review ends with a mention of color Doppler echocardiography. (E-mail:

Eutrophication as a result of human activity has resulted in increased algal blooms and turbidity in aquatic environments. We investigated experimentally the effect of algal turbidity on the mating system and sexual selection in the sand goby, Pomatoschistus minutus (Pallas), a marine fish with a resource-defence mating system and paternal care. Owing to male-male competition and female choice, large males can monopolize multiple mates, while some males do not achieve mating at all. We show that the number of eggs laid was the same in both turbid and clear tanks but that mating success was more evenly distributed among males in turbid than in clear water. The opportunity for sexual selection was lower in turbid conditions. In turbid conditions mating success was less skewed towards large males. Our results suggest that increased turbidity can change mating systems and decrease the opportunity for sexual selection as well as selection intensity.

Ninety-five rhizobial strains isolated from Astragalus adsurgens growing in the northern regions of China were classified into three main groups, candidate species I, II and III, based on a polyphasic approach. Comparative analysis of full-length 16S rRNA gene sequences of representative strains showed that candidate species I and II were Mesorhizobium, while candidate species III, which consisted of non-nodulating strains, was closely related to Agrobacterium tumefaciens. The phylogenetic relationships of the three candidate species and some related strains were also confirmed by the sequencing of glnA genes, which were used as an alternative chromosomal marker. The DNA-DNA relatedness was between 11.3 and 47.1 % among representative strains of candidate species I and II and the type strains of defined Mesorhizobium species. Candidate III had DNA relatedness of between 4.3 and 25.2 % with type strains of Agrobacterium tumefaciens and Agrobacterium rubi. Two novel species are proposed to accommodate candidate species I and II, Mesorhizobium septentrionale sp. nov. (type strain, SDW014(T)=CCBAU 11014(T)=HAMBI 2582(T)) and Mesorhizobium temperatum sp. nov. (type strain, SDW018(T)=CCBAU 11018(T)=HAMBI 2583(T)), respectively. At least two distinct nodA sequences were identified among the strains. The numerically dominant nodA sequence type was most similar to that from the Mesorhizobium tianshanense type strain and was identified in strains belonging to the two novel species as well as other, as yet, undefined genome types. Host range studies indicate that the different nodA sequences correlate with different host ranges. Further comparative studies with the defined Agrobacterium species are needed to clarify the taxonomic identity of candidate species III.

The adenosine receptor agonist 2-[ p-(2-carboxyethyl)phenylethylamino]-5'- N-ethylcarboxamidoadenosine (CGS 21680) is generally considered to be a selective adenosine A(2A) receptor ligand. However, the compound has previously been shown to exhibit binding characteristics that are not compatible with adenosine A(2A) receptor binding, at least in brain regions other than the striatum. We have examined binding of [(3)H]CGS 21680 and of antagonist radioligands with high selectivity for adenosine A(1) or A(2A) receptors to hippocampus and striatum of mice lacking either adenosine A(1) (A1R((-/-))) or A(2A) (A2AR((-/-))) receptors. Both receptor autoradiography and membrane binding techniques were used for this purpose and gave similar results. There were no significant changes in the binding of the A(1) receptor antagonist [(3)H]DPCPX in mice lacking A(2A) receptors, or in the binding of the A(2A) receptor antagonists [(3)H]SCH 58261 and [(3)H]ZM 241385 in mice lacking A(1) receptors. Furthermore, [(3)H]CGS 21680 binding in striatum was abolished in the A2AR((-/-)), and essentially unaffected in striatum from mice lacking A(1) receptors. In hippocampus, however, binding of [(3)H]CGS 21680 remained in the A2AR((-/-)), whereas binding was virtually abolished in the A1R((-/-)). There were no adaptive alterations in A(2A) receptor expression in this region in A1R((-/-)) mice. Thus, most of the [(3)H]CGS 21680 binding in hippocampus is dependent on the presence of adenosine A(1) receptors, but not on A(2A) receptors, indicating a novel binding site or novel binding mode.

Eighty-seven rhizobial strains isolated from root nodules of field standing native and exotic woody legumes in southern Ethiopia were characterized using the Biolog method and AFLP fingerprinting technique. Cluster analysis of the metabolic and genomic fingerprints revealed 18 and 25 groups, respectively, demonstrating considerable diversity in rhizobial population indigenous to Ethiopian soils. While 25 strains (29%) were linked to members of Agrobacterium, Bradyrhizobium, Mesorhizobium, Rhizobium or Sinorhizobium, the bulk of the strains formed several distinct groups in both methods and did not relate to reference species included in the study. In contrast to exotic species which formed symbiosis with strains of only one specific genomic group, indigenous host species nodulated by metabolically and genomically diverse groups. The results in this study support the view, that long-term association between the symbionts allows gradual differentiation and diversity in compatible rhizobial population resident in native soils. Lack of significant metabolic and genomic relatedness to the reference strains in our results suggested that test strains in our collection probably included 'unique' types, which belong to several yet undefined rhizobial species.

Sinorhizobium arboris and S. kostiense are rhizobia that nodulate the tropical leguminous trees Acacia senegal and Prosopis chilensis. The lipochito-oligosaccharidic signalling molecules (LCOs) of S. arboris HAMBI 2361 and S. kostiense HAMBI 2362 were analyzed by mass spectrometry. The major LCOs produced by the strains were shown to be pentameric, acylated with common fatty acids, N-methylated, O-6-carbamoylated and partially sulfated, as are the LCOs characterized to date for other Acacia-nodulating rhizobia. Besides the major LCOs the two strains produced (i) tetrameric LCOs, (ii) LCOs acylated with fatty acids other than those commonly found, (iii) LCOs with only an acyl substituent and (iv) noncarbamoylated LCOs. Production of LCOs (i) to (iii) are novel among Acacia-nodulating rhizobia. The roles of the different structural characteristics of LCOs in the rhizobium-A. senegal symbiosis are discussed. Specific structural features of the LCOs are proposed to be important in the selection of effective nitrogen-fixing rhizobia by A. senegal.

A 1-y retrospective study of problem oriented electronic patient records, for encounters concerning respiratory tract infection, was performed. The aim was to analyse the management of respiratory tract infections in primary health care in terms of diagnostic coding, tests and antibiotic treatment using data from electronic patient records. 12 primary health care centres with a registered population of 102,050 residents in 3 counties in southeast Sweden participated. Data were retrieved electronically from records of patient encounters concerning respiratory tract infections. The data were: patient age and gender, date of contact, diagnostic code, CRP and GABHS tests and results, as well as antibiotic prescriptions. In a total of 19,965 encounters, the most frequent diagnoses were common cold (40%), acute tonsillitis (18%), and acute bronchitis (15%). A total of 4445 GABHS tests (in 22% of encounters) and 6141 CRP tests (31%) were performed, and both tests were done in 1910 encounters (10%). A total of 7934 antibiotic prescriptions were registered. The proportion of patients tested and prescribed an antibiotic varied greatly between centres. We found an excessive, and much varying, use of rapid tests in encounters for respiratory tract infections. Data retrieval from electronic patient record systems was a feasible method to study the use of laboratory tests in relation to pharmacological treatment.

Diagnoses and antibiotic treatments were analysed in relation to respiratory tract infections (RTI). A 1-y retrospective study was made of electronic patient records (EPR) for encounters concerning RTIs in primary health care in Sweden. The study covered a registered population of 102,050 individuals at 12 primary health care centres in 3 counties. Data were recorded on number of episodes, encounters, diagnostic codes and antibiotic prescriptions. The yearly number of episodes of RTIs was 16,964 or 166 per 1000 inhabitants per y. The total number of encounters was 19,965. The most frequent diagnoses were common cold (40%), acute tonsillitis (18%), and acute bronchitis (15%). The yearly number of antibiotic prescriptions was 7961, accounting for 47% of the episodes or 78 per 1000 inhabitants per y. The most frequently prescribed antibiotics were phenoxymethylpenicillin (61%), tetracyclines (18%) and macrolides 8%). Standard EPRs provide a feasible source of clinical information which, taking limitations into consideration, could be used for the follow-up of trends in antibiotic prescribing and of adherence to guidelines with regard to RTIs.

Objective: To evaluate the effect of a health dialogue on lifestyle habits, and to relate the lifestyle changes to changes of biological risk markers for ischaemic heart disease., Design: Cross-sectional study, intervention and follow-up., Setting: The community of Habo, population 9500, located in Skaraborg, Sweden., Patients: All 35-year-old inhabitants in Habo were invited to a health examination during a study period between 1989 and 1992. A community intervention programme was combined with a health examination consisting of a health dialogue with a specially trained nurse and use of a "health curve" as an educational tool. The effect of the health examination was examined by comparing baseline characteristics of participants in 1989-1992 with their follow-up data in 1993., Results: Participants in the health dialogue who were re-examined reported lifestyle improvements including less smoking, decreased dietary fat intake and increased physical activity. Those who reported improved dietary intake and increased physical activity improved their biological risk markers correspondingly (body mass index, waist to hip ratio, serum cholesterol concentration)., Conclusions: The combination of a community and an individually based health programme can be effective with respect to lifestyle variables and, in those improving their lifestyle, in biological risk markers.

Abstract A non-indigenous wild-type strain Rhizobium galegae HAMBI 540, which specifically nodulates perennial goat's rue (Galega orientalis), and its marker gene-tagged derivatives R. galegae HAMBI 2363(luc), R. galegae HAMBI 2368(gusA21) and R. galegae HAMBI 2364(gusA30) were used to evaluate the persistence, population dynamics and competitiveness for nodulation of rhizobia under field conditions in Finland. The lysimeters were filled with clean or diesel oil-polluted (3000 mug g(-1)) agricultural soil. During the first 2 years of the field release luc- and gusA21-tagged strains could be effectively detected by cultivation, reinforced with colony polymerase chain reaction. The population densities remained relatively stable from 10(4) to 10(5) cfu g(-1) dry soil from spring until late autumn. Replicate limiting dilution polymerase chain reaction analysis gave comparable results with cultivation with strain HAMBI 2363 until 49 weeks after inoculation. GUS activity of strain HAMBI 2368 could be stably detected in nodules and soil. On the other hand, luc activity weakened clearly in cold conditions along with decreased metabolic activity of rhizobia. The competitive ability for nodulation of the gusA30-tagged strain decreased slowly with time compared to the wild-type strain. Moderate soil pollution did not have significant effects on target bacteria or plant growth. Limited vertical movement of target bacteria outside the rhizosphere was detected from percolated water.

N2-fixing, drought tolerant and multipurpose Acacia and Prosopis species are appropriate trees for reforestation of degraded areas in arid and semiarid regions of the tropics and subtropics. Acacia and Prosopis trees form N2-fixing nodules with a wide range of rhizobia, for example African acacias mainly with Sinorhizobium sp. and Mesorhizobium sp., and Australian acacias with Bradyrhizobium sp. Although dry and hot seasons restrict formation of N2-fixing nodules on Acacia and Prosopis spp., fully grown trees and their symbiotic partners are well adapted to survive in harsh growth conditions. This review on one hand deals with major constraints of arid and semiarid soils, i.e. drought, salinity and high soil temperature, which affect growth of trees and rhizobia, and on the other hand with adaptation mechanisms by which both organisms survive through unfavourable periods. In addition, defects in infection and nodulation processes due to various abiotic and biotic constraints are reviewed. This knowledge is important when Acacia and Prosopis seedlings are used for forestation of degraded areas in arid and semiarid tropics.

During recent years, the radial movement of the arterial wall has been extensively studied, and measurements of the radial movement are now an important tool in cardiovascular research for characterizing the mechanical properties of the arterial wall. In contrast, the longitudinal movement of vessels has gained little or no attention as it has been presumed that this movement is negligible. With modern high-resolution ultrasound, it can, however, be seen that the intima-media complex of the arterial wall moves not only in the radial direction, but also in the longitudinal direction during pulse-wave propagation. This paper describes a new non-invasive ultrasonic method that is able to measure simultaneously two dimensionally arterial vessel wall movements. The method is demonstrated in a limited in vivo trial. Results from the in vivo trial show that, apart from the well-known radial movement, there is a distinct longitudinal movement in the human common carotid artery with, in this case, the intima-media complex moving substantially as compared with the region of the tunica adventitia. Two-dimensional evaluation of the vessel-wall movements, taking not only the radial movement, but also the longitudinal movement into account, may provide novel information of importance in the evaluation of vessel-wall function.

It is evident from complete genome sequencing results that lateral gene transfer and recombination are essential components in the evolutionary process of bacterial genomes. Since this has important implications for bacterial systematics, the primary objective of this study was to compare estimated evolutionary relationships among a representative set of alpha-Proteobacteria by sequencing analysis of three loci within their rrn operons. Tree topologies generated with 16S rRNA gene sequences were significantly different from corresponding trees assembled with 23S rRNA gene and internally transcribed space region sequences. Besides the incongruence in tree topologies, evidence that distinct segments along the 16S rRNA gene sequences of bacteria currently classified within the genera Bradyrhizobium, Mesorhizobium and Sinorhizobium have a reticulate evolutionary history was also obtained. Our data have important implications for bacterial taxonomy, because currently most taxonomic decisions are based on comparative 16S rRNA gene sequence analysis. Since phylogenetic placement based on 16S rRNA gene sequence divergence perhaps is questionable, we suggest that the proposals of bacterial nomenclature or changes in their taxonomy that have been made may not necessarily be warranted. Accordingly, a more conservative approach should be taken in the future, in which taxonomic decisions are based on the analysis of a wider variety of loci and comparative analytical methods are used to estimate phylogenetic relationships among the genomes under consideration.

Objective: To analyse the influence of rates of general practitioner visits on rates of hospitalisations., Design: Ecological cross-sectional study of factors influencing hospitalisation rates. Aggregated data on primary care centre area level., Setting: The county of Ostergötland, Sweden, with 3 hospital districts and 41 primary health care centres, and the hospital district of Jönköping in the county of Jönköping, Sweden, with 11 primary health care centres., Outcome Measure: Hospitalisation rates., Results: Age and rates of outpatient hospital visits were the most important factors explaining the variation in rates of hospitalisations between the primary health care centre areas. Hospital districts, socioeconomic factors and rates of GP visits also influenced the rates of hospitalisations., Conclusion: When evaluating the influence of primary health care on the rates of hospitalisations, both socioeconomic factors and health care structure must be taken into consideration. Doing this, the rates of GP visits correlated negatively with the rates of hospitalisations.

Within administrative surveying work in Sweden, a transition to a client-centered team-based organization was made during 1998. The aim of this study was to describe the employees' perceptions and expectations of job and organizational practices when working as a generalist in a client-centered team-based organization; job and organizational practices and well-being and effectiveness measures were examined when introducing a team-based organization. Interventions such as courses in how to cope with the role of a generalist, how to increase service to clients, education in technology, law and economics, as well as computer information support, were ongoing at the time of the study. The Team Work Profile and QPS Nordic questionnaires were used. All the surveyors in five regions in Sweden participated, in total 640 surveyors. The transition to a client-centered team-based organization was expected to improve job control and job content but at the same time lead to impairments in job climate and group cohesion. Distress was associated with negative future expectations of the organization. High job control and group cohesion were the central contributors towards growth in personal competence and social effectiveness of teamwork. Both internal and external client-related activities of team and organization were in focus during the transition., (Copyright 2003 Elsevier Science Ltd.)

Rhizobial nodD genes produce transcriptional regulators that, together with appropriate inducer compounds, activate the other symbiotic nodulation (nod) genes and initiate the nodule formation process. Two nodD homologues, nodD1 and nodD2, are present in the Rhizobium galegae strain HAMBI 1174. In this work we analysed their ability to induce the nodA promoter with synthetic inducers known to activate nod genes in other rhizobia. According to phylogenetic analysis, the inducer-specific carboxy-terminal part of the R. galegae nodD protein sequence groups together with those of Rhizobium leguminosarum and Sinorhizobium meliloti. However, the respective inducer compounds for their NodD proteins are not highly effective with R. galegae nodD products. The best inducer discovered with R. galegae nodD1 was the root exudate of the host plant of R. galegae, Galega orientalis. HPLC analyses revealed the presence of many divergent flavonoid compounds in the G. orientalis root exudate. The most effective HPLC fractions induced R. galegae nodD1 up to the level obtained by intact G. orientalis root exudate while apigenin and luteolin, which were also present in the root exudate, were only moderate inducers. A UV-Vis diode array spectrum of the most active peak indicated that the main inducer present in the G. orientalis root exudate is an unidentified chalcone-type compound. In the Galega-R. galegae interaction the first recognition between the NodD protein and the flavonoid inducer secreted from the roots of Galega is specific for these organisms, and thus partly responsible of the strict host specificity of this symbiosis.

This paper explores the relationship between the genetic diversity of rhizobia and the morphological diversity of their plant hosts. Rhizobium galegae strains were isolated from nodules of wild Galega orientalis and Galega officinalis in the Caucasus, the center of origin for G. orientalis. All 101 isolates were characterized by genomic amplified fragment length polymorphism fingerprinting and by PCR-restriction fragment length polymorphism (RFLP) of the rRNA intergenic spacer and of five parts of the symbiotic region adjacent to nod box sequences. By all criteria, the R. galegae bv. officinalis and R. galegae bv. orientalis strains form distinct clusters. The nod box regions are highly conserved among strains belonging to each of the two biovars but differ structurally to various degrees between the biovars. The findings suggest varying evolutionary pressures in different parts of the symbiotic genome of closely related R. galegae biovars. Sixteen R. galegae bv. orientalis strains harbored copies of the same insertion sequence element; all were isolated from a particular site and belonged to a limited range of chromosomal genotypes. In all analyses, the Caucasian R. galegae bv. orientalis strains were more diverse than R. galegae bv. officinalis strains, in accordance with the gene center theory.

Speckle in continuous wave (CW) Doppler has previously been found to cause large variations in detected Doppler power in blood perfusion measurements, where a large number of blood vessels are present in the sample volume. This artifact can be suppressed by using a number of simultaneously transmitted frequencies and averaging the detected signals. To optimize the strategy, statistical properties of speckle in CW ultrasound need to be known. This paper presents analysis of the frequency separation necessary to obtain independent values of the received power for CW ultrasound using a simplified mathematical model for insonation of a static, lossless, statistically homogeneous, weakly scattering medium. Specifically, the autocovariance function for received power is derived, which functionally is the square of the (deterministic) autocorrelation function of the effective sample volumes produced by the transducer pair for varying frequencies, at least if a delta correlated medium is assumed. A marginal broadening of the modeled autocovariance functions is expected for insonation of blood. The theory is applicable to any transducer aperture, but has been experimentally verified here with 5-MHz, 6.35-mm circular transducers using an agar phantom containing small, randomly dispersed glass particles. A similar experimental verification of a transducer used in multiple-frequency blood perfusion measurements shows that the model proposed in this paper is plausible for explaining the decorrelation between different channels in such a measurement.

Differential display was applied in order to clone cDNAs expressed exclusively or predominantly in nodules, compared to uninoculated root tissue of Galega orientalis. Forty-five fragments were unique for nodule RNA. These fragments were reamplified and cloned. Six of them produced a nodule-specific signal on Northern hybridization. These six fragments were sequenced. Five of the sequenced fragments showed homology to nodulin-gene sequences in databases, among them Vicia faba mRNA for protein showing partial homology with Medicago sativa nodulin-25 (Nms25), Pisum sativum PsN466, V. faba CCP2 and CCP4, P. sativum ENOD3, and Maackia amurensis ENOD2. The remaining sequence had no significant homology with sequences in the databanks. Full-size cDNA for the homologue to V. faba mRNA for the protein showing partial homology with M. sativa nodulin-25 (Nms25) and P. sativum PsN466 were cloned and sequenced.

Objective: To study the trend in premature mortality (before 75 years of age) from ischaemic heart disease (IHD) in a Swedish primary health care district compared to communities of similar demographic situation and all Sweden., Design: Mortality from IHD in men and women was compared between the community of Habo and other Swedish communities of similar size and all Sweden for the period 1984-96., Setting: The community of Habo in Sweden with about 9600 inhabitants., Intervention: Intensified efforts by the local primary health care organisation, in co-operation with the community, in respect of primary and secondary cardiovascular prevention since the beginning of the 1980s., Results: Mortality from IHD has decreased significantly both in Habo and in Sweden during these years. The decrease has been more prominent in Habo than in Sweden as a whole and other Swedish communities of similar demographic situation., Conclusion: With increased and purposeful efforts in primary and secondary prevention, in co-operation between the community and primary health care, it is possible to substantially decrease mortality from IHD in the community.

The standard way of suppressing movement artefacts in Doppler measurements is by means of a high-pass filter. This is because artefacts usually are of high amplitude, but have low frequencies. The immediate drawback is, then, that low-velocity blood flow is also filtered out. In this paper, a method to reduce movement artefacts in blood perfusion measurements is proposed, using simultaneous transmission and reception of multiple frequencies in a continuous-wave Doppler system. It is shown that Doppler signals originating from blood may be considered uncorrelated for a large enough frequency separation between channels, and tissue movements are more correlated. By subtracting perfusion estimates obtained by time-domain processing, correlated signals can be suppressed. The subtraction algorithm is shown to produce a linear perfusion estimate, but with twice the standard deviation compared to an estimate obtained by simply averaging channels. Movement artefacts in both in vitro and in vivo models are shown to be reduced by the algorithm. Imbalance between channels does, however, cause the artefacts to be only partly reduced. The problem can be alleviated by filtering the signals prior to subtraction, but this results in a nonlinear estimate, especially for large time constants in the filter. Some amount of filtering can still be desirable to suppress partly correlated artefacts, even if identical time-domain processing units are implemented, as could be done digitally.

The genetic diversity among 95 isolates from Astragalus adsurgens was investigated using molecular biological methods. All of the isolates and 24 reference strains could be differentiated by AFLP, REP-, ERIC- and BOX-PCR fingerprinting analysis. By cluster analysis of the data, 31 AFLP and 38 Rep-PCR genomic groups were delineated, indicating considerable genetic diversity among the isolates. Fifty-four representative strains were further analyzed by RFLP of PCR-amplified 16S and 23S rDNA, revealing 26 rDNA genotypes among the isolates. The phylogenetic relationship of the isolates was determined by partial sequencing of 16S rRNA genes of 16 strains. The results suggest that the A. adsurgens rhizobia belong to the genera Agrobacterium, Mesorhizobium, Rhizobium and Sinorhizobium.

AFLP fingerprints of Rhizobium galegae strains that infect Galega orientalis and Galega officinalis obtained from different geographical sources, and of taxonomically diverse rhizobia representing the recognized species, were generated. Comparisons of the fingerprints from fluorescent labeled AFLP products using capillary electrophoresis on ABI prism 310, slab gel electrophoresis on ABI prism 377 genetic analyzers and silver staining were in good agreement. All methods delineated the G. orientalis strains from G. officinalis strains, the G. orientalis strains formed a tight cluster whereas the G. officinalis strains seem to show a greater level of genetic diversity. Comparison of fluorescent AFLP with other detection methods revealed that fluorescent labeling is more sensitive and practical, in addition, the deleterious effect of radioactivity associated with 32P-labeling, the delicate process of blotting polyacrylamide gels or the tedious procedure of silver staining can be avoided. The automated system facilitated a large number of runs at a time and the subsequent analysis of the data by generating exportable raw data. The congruency of the experiments was analyzed using the Bionumerics software.

Alternative mating strategies are common in nature and are generally thought to increase the intensity of sexual selection. However, cuckoldry can theoretically decrease the opportunity for sexual selection, particularly in highly polygamous species. We address here the influence of sneaking (fertilization thievery) on the opportunity for sexual selection in the sand goby Pomatoschistus minutus, a marine fish species in which males build and defend nests. Our microsatellite-based analysis of the mating system in a natural sand goby population shows high rates of sneaking and multiple mating by males. Sneaker males had fertilized eggs in approximately 50% of the assayed nests, and multiple sneakers sometimes fertilized eggs from a single female. Successful males had received eggs from 2 to 6 females per nest (mean = 3.4). We developed a simple mathematical model showing that sneaking in this polygynous sand goby population almost certainly decreases the opportunity for sexual selection, an outcome that contrasts with the usual effects of cuckoldry in socially monogamous animals. These results highlight a more complex and interesting relationship between cuckoldry rates and the intensity of sexual selection than previously assumed in much of the literature on animal mating systems.

I describe the results of an experimental manipulation of resource availability (nest substrate) and distribution (nest size), leading to effects on the opportunity for sexual selection and the survival of male sandgobies Pomatoschistus minutus competing for these resources. This study represents one of few such experimental manipulations. It shows a clear-cut effect of male-male competition on the survival of males, and it shows temporal variation in the opportunity for sexual selection, suggesting that short-term assessment of sexual selection could be misleading. Males breeding under male-male competition for nest sites lived on average 18 d less than males in the high-nest-availability treatment. This considerable cost of reproduction probably stems from increased stress levels as a result of higher levels of aggression. The opportunity for sexual selection was high throughout the 2-mo experiment in the low-nest-availability treatment, while in the high nest availability, it changed in a complex manner over the season. In the latter case, sexual selection was initially low but increased during midseason to values nearly as high as in the nest-site-limited environment and then decreased again toward the end of the season. Previous studies have shown that temporal variation in sexual selection follows variation in population density and sex ratio. This study demonstrates that there can be considerable temporal variation in the opportunity for sexual selection without changes in population parameters.

Twenty-six Rhizobium galegae strains, representing the center of origin of the host plants Galega orientalis and G. officinalis as well as other geographic regions, were used in a polyphasic analysis of the relationships of R. galegae strains. Phage typing, lipopolysaccharide (LPS) profiling, pulsed field gel electrophoresis (PFGE) profiling and rep-PCR (use of repetitive sequences as PCR primers for genomic fingerprinting) with REP and ERIC primers investigated nonsymbiotic properties, whereas plasmid profiling and hybridisation with a nif gene probe, and with nodB, nodD, nod box and an IS sequence from the symbiotic region as probes, were used to reveal the relationships of symbiotic genes. The results were used in pairwise calculations of distances between the strains, and the distances were visualised as a dendrogram. Indexes of association were compared for all tests pooled, and for chromosomal tests and symbiotic markers separately, to display the input of the different categories of tests on the grouping of the strains. Our study shows that symbiosis related genetic traits in R. galegae divide strains belonging to the species into two groups, which correspond to strains forming an effective symbioses with G. orientalis and G. officinalis respectively. We therefore propose that Rhizobium galegae strains forming an effective symbiosis with Galega orientalis are called R. galegae bv. orientalis and strains forming an effective symbiosis with Galega officinalis are called R. galegae bv. officinalis.

Application of DNA fingerprinting methods enables the detection of diverse members of soil bacterial consortia, even including those bacteria not yet cultivated. However, extraction and purification of DNA from soil samples without bias is difficult. We compared five different DNA isolation methods and three purification methods for rhizosphere soil samples. Purified DNA extracts were amplified in PCR using universal bacterial primers and the PCR products were analysed with denaturing gradient gel electrophoresis (DGGE) for the visualisation of DNA bands representing dominant bacterial species. Both the isolation and purification methods affected the apparent bacterial community structure of the samples.

The effect of shape on the transglomerular passage of solutes has not been hitherto systematically studied. We perfused isolated rat kidneys to determine the fractional clearances (theta) at various filtration rates for four molecules of different shapes but with similar Stokes-Einstein radii (aSE = 34-36 A). The theta for hyaluronan, bikunin, and Ficoll36 A were 66, 16, and 11%, respectively, at a glomerular filtration rate (GFR) of 0.07 ml x min(-1) x g wet wt(-1) and decreased to 46, 14, and 7%, respectively, on a fivefold increase in GFR. Under the same conditions, theta for albumin increased from 0.15 to 0.74%, and similar behavior was observed for larger Ficolls (aSE >45 A). Pore analysis showed that the "apparent neutral" solute radii of Ficoll, albumin, bikunin, and hyaluronan were 35, 64, 33, and 24 A, respectively, despite similar aSE. In addition, the properties of the glomerular filter changed with increasing GFR and hydrostatic pressure. We conclude that elongated shape, irrespective of size and charge, drastically increases the transglomerular passage of a solute, an effect that is related to its frictional ratio.

Rhizobia are soil bacteria able to fix atmospheric nitrogen in symbiosis with leguminous plants. In response to a signal cascade coded by genes of both symbiotic partners, a specific plant organ, the nodule, is formed. Rhizobial nodulation (nod) genes trigger nodule formation through the synthesis of Nod factors, a family of chitolipooligosaccharides that are specifically recognized by the host plant at the first stages of the nodulation process. Here, we present the organization and sequence of the common nod genes from Rhizobium galegae, a symbiotic member of the RHIZOBIACEAE: This species has an intriguing phylogenetic position, being symbiotic among pathogenic agrobacteria, which induce tumors instead of nodules in plant shoots or roots. This apparent incongruence raises special interest in the origin of the symbiotic apparatus of R. galegae. Our analysis of DNA sequence data indicated that the organization of the common nod gene region of R. galegae was similar to that of Sinorhizobium meliloti and Rhizobium leguminosarum, with nodIJ downstream of nodABC and the regulatory nodD gene closely linked to the common nod operon. Moreover, phylogenetic analyses of the nod gene sequences showed a close relationship especially between the common nodA sequences of R. galegae, S. meliloti, and R. leguminosarum biovars viciae and trifolii. This relationship in structure and sequence contrasts with the phylogeny based on 16S rRNA, which groups R. galegae close to agrobacteria and separate from most other rhizobia. The topology of the nodA tree was similar to that of the corresponding host plant tree. Taken together, these observations indicate that lateral nod gene transfer occurred from fast-growing rhizobia toward agrobacteria, after which the symbiotic apparatus evolved under host plant constraint.

During 1997-1999, we collected serum samples from 156 common eider (Somateria mollissima) females incubating eggs in the Finnish archipelago of the Baltic Sea. We used serum chemistry profiles to evaluate metabolic changes in eiders during incubation and to compare the health and nutritional status of birds nesting at a breeding area where the eider population has declined by over 50% during the past decade, with birds nesting at two areas with stable populations. Several changes in serum chemistries were observed during incubation, including (1) decreases in serum glucose, total protein, albumin, beta-globulin, and gamma-globulin concentrations and (2) increases in serum uric acid, creatine kinase, and beta-hydroxybutyrate concentrations. However, these changes were not consistent throughout the 3-yr period, suggesting differences among years in the rate of carbohydrate, lipid, and protein utilization during incubation. The mean serum concentrations of free fatty acids, glycerol, and albumin were lowest and the serum alpha- and gamma-globulin levels were highest in the area where the eider population has declined, suggesting a role for nutrition and diseases in the population dynamics of Baltic eiders.

Study Objective: To evaluate a health promotion programme, combining a population and individual based strategy, in the County of Skaraborg, Sweden, with special attention to outcome., Design: The evaluation was subdivided into structure, process and outcome. The evaluation procedure as a total is described here, but the results presented refer only to outcome. In order to study the potential effect of the individually based health examination, 35 year old subjects who had participated five years previously were in 1994-1996 compared with 35 year old subjects who had not participated before, and compared with their own values five years earlier. The results during 1995-1996 were compared with those of 1989-1990 for corresponding ages in order to study the effect of, particularly, the population based strategy., Setting: The County of Skaraborg in the south western part of Sweden with about 270 000 inhabitants. In addition to population strategy, involving the total county, men and women aged 30 and 35 years were invited to an individually based examination., Main Results: Factors related to body weight increased during the study period, while other factors mostly changed in the direction wanted. As a whole the changes were rather modest. There were favourable changes in lifestyle variables, for example, concerning smoking and dietary habits., Conclusions: There were beneficial effects from the health promotion programme, but there is a need for continuous improvement of methods of intervention referred to lifestyle.

The Sindbis virus uses birds as vertebrate hosts in the summer amplification cycle, and the virus is transmitted by ornithophilic Culex species. Previous field and experimental studies have shown that mainly passerine birds are involved in the amplification. To delineate the pattern of Sindbis virus infections among passerines, we collected and sampled birds for blood at five study sites located in northern, central, and southern Sweden. All study sites were lowland forested wetlands and humid forests. The blood samples were assayed for Sindbis neutralizing antibodies, and we tested if the prevalence of Sindbis antibodies varied in relation to bird characteristics (i.e., species, body-mass, sex, and age), and environmental factors (i.e., year, month, and location). We found that Sindbis virus infections occurred in almost all passerine species sampled, but that the infection prevalence was unequally distributed among species. The fieldfare, the redwing, and the songthrush each had significantly higher prevalence than the average for all species. Large passerine species had higher infection prevalence than small species. The infection was less prevalent in hatching-year birds than in older birds during June and July, but not in August. Males and females had the same infection prevalence. The prevalence of Sindbis antibodies was higher in central than in southern Sweden, which coincided with a higher proportion of fieldfare-redwing-songthrush samples in the central region of the country. Thus, it is possible that regional and annual variations in the prevalence of Sindbis antibodies in Swedish passerine species depend on the number of fieldfares, redwings, and songthrushes available for feeding by vector mosquitoes.

Molecular markers have proved extremely useful in resolving mating patterns within individual populations of a number of species, but little is known about how genetic mating systems might vary geographically within a species. Here we use microsatellite markers to compare patterns of sneaked fertilization and mating success in two populations of sand goby (Pomatoschistus minutus) that differ dramatically with respect to nest-site density and the documented nature and intensity of sexual selection. At the Tvärminne site in the Baltic Sea, the microsatellite genotypes of 17 nest-tending males and mean samples of more than 50 progeny per nest indicated that approximately 35% of the nests contained eggs that had been fertilized by sneaker males. Successful nest holders mated with an average of 3.0 females, and the distribution of mate numbers for these males did not differ significantly from the Poisson expectation. These genetically deduced mating-system parameters in the Tvärminne population are remarkably similar to those in sand gobies at a distant site adjoining the North Sea. Thus, pronounced differences in the ecological setting and sexual selection regimes in these two populations have not translated into evident differences in cuckoldry rates or other monitored patterns of male mating success. In this case, the ecological setting appears not to be predictive of alternative male mating strategies, a finding of relevance to sexual selection theory.

The immunocompetence-handicap hypothesis suggests that the honesty of quality signals could be guaranteed if testosterone (T) suppresses immune function while enhancing male ornaments. In addition, it has been proposed that the cost of enhancing ornaments should be highest for males with small ornaments. Recently, the assertion that T causes obligate immunosuppression has been questioned. In this study, we tested whether elevated T levels would increase susceptibility to a viral infection, and whether this hypothesized effect would be most pronounced in males with small ornaments. We surgically inserted T implants into 15 male greenfinches (Carduelis chloris) and control implants into a further 15 males. All birds were then infected with a naturally occurring virus (Sindbis virus, Alphavirus genus), and each bird's daily viraemia (blood virus concentration) was measured for seven days. The specific antibody response was measured for eight weeks. T-implanted males did not exhibit increased viraemia or decreased antibody response, and males with small and large ornaments did not respond differently to T implantation. We did, however, find that T implantation decreased viraemia early in the course of the infection and increased viraemia late in the infection. Thus, our results demonstrate that T may act both to increase and to decrease viraemia.

The effect of heat stress on the growth, physiological state, cell activity and cell morphology of the tropical Sinorhizobium arboris strain HAMBI 2190 was studied. The cells were chromosomally tagged with the firefly luciferase gene, luc. Since the bioluminescence phenotype is dependent on cellular energy reserves it was used as an indicator of the metabolic status of the cell population under various heat conditions. Variations in the numbers and lengths of growth phases between individual cultures indicated that the growth pattern at 40 degrees C was disturbed compared to growth at 37 or 28 degrees C. In addition, the cell morphology was changed radically. The number of culturable cells and the luciferase activity declined when the cultures were incubated at 40 degrees C. By contrast, under all conditions studied, the cells could be stained with 5-(and 6-)sulfofluorescein diacetate, indicating esterase activity. This demonstrated that although the culturability and cellular energy reserves decreased considerably during heat stress, a majority of the of S. arboris cell population maintained basal enzyme activity.

Objective: To study the possibility of using the computerised journal for quality improvement in diabetes care., Design: The computerised journal was used to reach all diabetic smokers aged 30-75 years and to invite them to a structured smoking cessation programme. The follow-up time was 18 months., Setting: Habo, a Swedish community with 9600 inhabitants, with one primary health care centre., Subjects: 147 subjects, aged 30-75 years, were registered with the diagnosis of diabetes mellitus in the computerised journal at the primary health care centre. Altogetber 25 of these patients were registered as smokers in the journal. All of them were invited to a smoking cessation group., Results: Information about smoking habits in the journal was available for all but 11%. After 18 months' follow-up, 9 of the 14 patients (64%) who started in the smoking cessation group had become non-smokers. Of those 11 subjects who did not attend the group, 6 had stopped smoking during the follow-up time in spite of not participating in the structured programme., Conclusion: The computerised journal is a useful tool for quality improvement, giving the opportunity for directed preventive efforts on selected patient groups.

It is well known that tolerance develops to the actions of caffeine, which acts as an antagonist on adenosine A(1) and A(2A) receptors. Since selective adenosine A(2A) antagonists have been proposed as adjuncts to 3,4-dihydroxyphenylalanine (L-DOPA) therapy in Parkinson's disease we wanted to examine if tolerance also develops to the selective A(2A) receptor antagonist 5-amino-7-(2-phenylethyl)-2-(2-furyl)-pyrazolo-[4,3-e]-1,2, 4-triazolo [1,5-c]pyrimidine (SCH 58261). SCH 58261 (0.1 and 7.5 mg/kg) increased basal locomotion and the motor stimulation afforded by apomorphine. Neither effect was subject to tolerance following long-term treatment with the same doses given intraperitoneally twice daily. There were no adaptive changes in A(1) and A(2A) adenosine receptors or their corresponding messenger RNA or in dopamine D(1) or D(2) receptors. These results demonstrate that the tolerance that develops to caffeine is not secondary to its inhibition of adenosine A(2A) receptors. The results also offer hope that long-term treatment with an adenosine A(2A) receptor antagonist may be possible in man.

Silver stained denaturing polyacrylamide gels (PAGEs) and fluorescent denaturing automated capillary electrophoresis (CE) were used to detect amplified fragment length polymorphism (AFLP) patterns obtained from white-rot fungi belonging to the genus Trametes. AFLP fingerprinting detected by the fluorescence-based method as well as by silver staining showed a high discriminatory power in differentiating nine strains of Trametes ochracea, nine strains of Trametes hirsuta and ten isolates of Trametes versicolor. UPGMA dendrograms derived from fluorescently labelled and silver stained AFLP patterns were similar, but a few differences were detected especially in the clustering of T. ochracea and T. hirsuta strains. Compared to silver-stained AFLP, detection of fluorescent AFLP was fast, reliable and easy to perform and it facilitated surveying with a computerized analysis system. Fluorescent CE seems to be well suited for studying similarity between Trametes species.