Human cytomegalovirus seropositivity is associated with reduced patient survival during sepsis

BACKGROUND

Sepsis is one of the leading causes of death. Treatment attempts targeting the immune response regularly fail in clinical trials. As HCMV latency can modulate the immune response and changes the immune cell composition, we hypothesized that HCMV serostatus affects mortality in sepsis patients.

METHODS

We determined the HCMV serostatus (i.e., latency) of 410 prospectively enrolled patients of the multicenter SepsisDataNet.NRW study. Patients were recruited according to the SEPSIS-3 criteria and clinical data were recorded in an observational approach. We quantified 13 cytokines at Days 1, 4, and 8 after enrollment. Proteomics data were analyzed from the plasma samples of 171 patients.

RESULTS

The 30-day mortality was higher in HCMV-seropositive patients than in seronegative sepsis patients (38% vs. 25%, respectively; p = 0.008; HR, 1.656; 95% CI 1.135-2.417). This effect was observed independent of age (p = 0.010; HR, 1.673; 95% CI 1.131-2.477). The predictive value on the outcome of the increased concentrations of IL-6 was present only in the seropositive cohort (30-day mortality, 63% vs. 24%; HR 3.250; 95% CI 2.075-5.090; p < 0.001) with no significant differences in serum concentrations of IL-6 between the two groups. Procalcitonin and IL-10 exhibited the same behavior and were predictive of the outcome only in HCMV-seropositive patients.

CONCLUSION

We suggest that the predictive value of inflammation-associated biomarkers should be re-evaluated with regard to the HCMV serostatus. Targeting HCMV latency might open a new approach to selecting suitable patients for individualized treatment in sepsis.

Institutions and institutional changes: aquatic food production in Central Luzon, Philippines

Aquaculture is the most rapidly growing food production sector globally. In certain coastal social-ecological systems, this has resulted in significant changes and sustainability challenges. In particular, coastal environments which used to support only capture fisheries are becoming sites for brackish water aquaculture production; this impacts the sustainability of aquatic food production. Sustainability challenges associated with aquaculture expansion and intensification necessitate a contextually rooted understanding of institutions and institutional changes which can be used as an informed basis for leveraging institutions to achieve desirable sustainability outcomes in the aquatic food sector. This research used a qualitative empirical case study involving in-depth interviews, participant observation, and analysis of institutional documents in the region of Central Luzon, Philippines. It applied the inter-institutional systems concept which considers multiple institutions with distinct but linked purposes and functions in the societal spheres of state, market, and civil society. The study found that aquaculture emerged as an important livelihood because of rice farmers' need to adapt to saltwater intrusion into what were formerly rice farms. It grew into an industry due to developments in the availability and accessibility of inputs such as fingerlings and feeds. This process was also driven by the high demand and high profitability of fish farming at the time. Regulatory institutions have not adequately adapted to protect the environment. Market institutions adapted but the changes mostly benefited consignacions (middlemen) and large-scale players. However, organised groups of collaborating smallholder fishers and fish farmers are helping to address the disadvantages they face.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s10113-021-01853-4.

Aquaculture-capture fisheries nexus under Covid-19: impacts, diversity, and social-ecological resilience

The Covid-19 pandemic is a global shock that is significantly affecting coastal social-ecological systems (SES) in different parts of the world. Its widespread impacts have unravelled vulnerabilities in many aspects of society, including food systems. Our study investigated the impacts of a lockdown associated with the pandemic in the province of Bulacan, in the region of Central Luzon, Philippines, where aquaculture and capture fisheries are important and interconnected sectors. In particular, we focused on impacts related to production and market. We considered people's coping strategies and the factors that enabled such strategies. Our investigation adopted a case study approach and drew on qualitative data analysed through thematic analysis. The findings revealed differentiated mechanisms through which aquaculture and capture fisheries production were impacted. Both were strongly affected by market disruptions but through slightly different ways. In effect, the lockdown provided the impetus for the uptake and spreading of practices that were previously peripheral, particularly in relation to market exchanges. The study also identified a variety of coping strategies, as well as the importance of social support in the form of food aid, financial assistance, and institutional livelihood assistance. Finally, it discusses the importance of diversity in food sources, the role of local food systems, and governance implications for foregrounding social-ecological resilience in short-term response and long-term recovery.

Phenotypic correlations in a large single-center cohort of patients with BSCL2 nerve disorders: a clinical, neurophysiological and muscle magnetic resonance imaging study

BACKGROUND AND PURPOSE

BSCL2 heterozygote mutations are a common cause of distal hereditary motor neuropathies (dHMNs). A series of BSCL2 patients is presented and clinical, neurophysiological and muscle magnetic resonance imaging (MRI) findings are correlated.

METHODS

Twenty-six patients from five families carrying the p.N88S mutation were identified. Age of onset, clinical phenotype (dHMN, Charcot-Marie-Tooth, spastic paraplegia), physical examination, disability measured as a modified Rankin Scale score and neurophysiological findings were collected. A whole body muscle MRI had been performed in 18 patients. The pattern of muscle involvement on T1-weighted and short time inversion recovery sequences was analysed. Hierarchical analysis using heatmaps and an MRI Composite Score were generated. Statistical analysis was carried out with STATA SE v.15 (TX, USA).

RESULTS

The mean age was 51.54 ± 19.94 years and 14 patients were men. dHMN was the most common phenotype (50%) and five patients (19.23%) showed no findings on examination. Disease onset was commonly in childhood and disability was low (modified Rankin Scale score 1.34 ± 1.13) although median time since onset of disease was 32 years (range 10-47). Charcot-Marie-Tooth-like patients were more disabled and disability correlated with age. On muscle MRI, thenar eminence, soleus and tibialis anterior were most frequently involved, irrespective of clinical phenotype. MRI Composite Score was strongly correlated with disability.

CONCLUSION

Patients with the p.N88S BSCL2 gene mutation are phenotypically variable, although dHMN is most frequent and generally slowly progressive. Muscle MRI pattern is consistent regardless of phenotype and correlates with disease severity, probably serving as a reliable outcome measure for future clinical trials.

Virtual reality as a tool for environmental conservation and fundraising

Anecdotal evidence from philanthropic fundraisers shows that virtual reality (VR) technology increases empathy and can influence people toward pro-environmental behavior. Non-profit organizations are increasingly marketing their causes using virtual reality and they report increased donations when VR technology is employed. In VR, users are immersed in situations intended to feel more like the real world through technology, such as 360° video viewed through 3D headsets that block out visual and auditory distractions. The framing of the message as either positive or negative has long shown to have an effect on behavior, although consensus on the impact of framing has not been reached in relation to encouraging contributions to public goods. This paper focuses on field experiments used to investigate the effects of varying degrees of visual immersion and positive versus negative message framing on respondents' contributions to a conservation charity. Participants were exposed to a five-minute underwater film about coral reefs and the importance of protecting them. We employed a 2x2 experimental design using 3D head-mounted displays comparing 360° film footage vs. unidirectional film and a positive message vs. a negative message. After watching the film, each participant completed a short questionnaire and had the opportunity to donate to a marine conservation charity. In addition, we tested a control treatment where no video was observed. The video was filmed in Indonesia which is host to some of the world's most biodiverse reefs that are under great threat from human activity. We also conducted the study in Indonesia, sampling a total of 1006 participants from the Bogor city area and tourists on the island of Gili Trawangan-which is popular for scuba diving and snorkeling. We find significant differences in observed behavior and reported emotions between all treatments compared to the control condition. Among the tourist sample, we find significant differences between the 360° film with a negative message which garnered significantly larger average donation amounts compared to the unidirectional film with both positive and negative framing. Overall, we can infer from these studies that virtual reality is an effective way to raise awareness of environmental threats and encourage behavioral action, especially when tailored to target groups. New technology, such as the VR head-mounted display, is highly effective at attracting interest which is an important point to encourage organizations to invest in new technologies.

Tropical marine sciences: Knowledge production in a web of path dependencies

Scientific agenda setting is critical at all levels of research, but can be strongly influenced by structural path dependencies of the science system itself. In this article we examine how knowledge production is shaped by interconnected path dependencies using the field of tropical marine sciences as a global case study. We use scientometric analysis methods on an original data set of 1328 peer-reviewed journal publications to examine publication trends including a co-authorship network analysis, links between author origin and research locations as well as a quantitative analysis of terminology use over space (i.e., region) and time. Scientometric findings are analytically discussed through a conceptual framework premised on theories of path dependency. Findings and critical analysis highlight how tropical marine science provides a prominent global example of how North American, European and Australian science programs predominantly shape knowledge production of the global science system, generating critical reflection on the path dependencies these create on current and likely future knowledge production and science agendas. Similar dependencies face other fields of science, and thus this study provides broadly relevant quantitative observational empirical findings supplemented with a critical social science analysis of how a transcultural Science and Technology Studies lens is useful for unpacking the webs of path dependencies driving, inhibiting and/ or shaping global knowledge production, placing meaning and context over observed empirical trends.

Nudging tourists to donate for conservation: Experimental evidence on soliciting voluntary contributions for coastal management

This research examines the donation behavior of tourists who are asked to donate to coastal conservation aimed at addressing a bundled mix of land and sea issues. Historically, the governance and financing of land and sea conservation have been separated; yet coastal tourism directly involves a mix of activities and development challenges which link land and sea together on the coast. Marine parks, and numerous studies examining their funding schemes, have typically focused on mandatory user fees targeting specific types of activities. For example, many studies focus only on scuba divers' willingness to pay (WTP) for marine conservation. Alternative funding mechanisms, such as voluntary contributions, may be preferred, or even necessary, to traditional government imposed fees, but much less is known about effective implementation. Relatively few studies focus on bundled cross-boundary conservation activities (i.e., land and sea conservation) from all visitors of a marine park (i.e., beachgoers, surfers, boaters, snorkelers) and its encompassing coastal area. In this study we target tourists visiting a popular island and employ field experimental methods to explore the optimal donation request mechanism and pricing levels that influence real voluntary payments for conservation. The field experiment examines voluntary payments under the treatment conditions: open-ended, a set of several suggested donation amounts, and default opt-in and opt-out at two price levels. The field experiment was conducted with tourists on the island of Gili Trawangan, Indonesia. Results reveal that tourists are willing to donate to bundled land-sea conservation issues and that there is a significantly higher propensity to donate in all treatment conditions compared to the open-ended condition. The default opt-out conditions garnered the highest rate of donations at 75% and 62% respectively for the lower and higher set amounts. The mean donation amount was largest in the higher default opt-out condition. Our results suggest that the optimal method of requesting voluntary donations is a set default amount requiring users to opt-out if they do not wish to donate. Implementing a default opt-out eco-donation targeting all types of visitors represents a significant source of funding and illustrates the potential for donations to finance land and sea conservation efforts, an important avenue for future investigation in many interconnected systems that have been historically governed and financed separately.

Sociocultural heterogeneity in a common pool resource dilemma

Collective action of resource users is essential for sustainability. Yet, often user groups are socioculturally heterogeneous, which requires cooperation to be established across salient group boundaries. We explore the effect of this type of heterogeneity on resource extraction in lab-in-the-field Common Pool Resource (CPR) experiments in Zanzibar, Tanzania. We create heterogeneous groups by mixing fishers from two neighbouring fishing villages which have distinct social identities, a history of conflict and diverging resource use practices and institutions. Additionally, we analyse between-village differences in extraction behaviour in the heterogeneous setting to assess if out-group cooperation in a CPR dilemma is associated with a community’s institutional scope in the economic realm (e.g., degree of market integration). We find no aggregate effect of heterogeneity on extraction. However, this is because fishers from the two villages behave differently in the heterogeneity treatment. We find support for the hypothesis that cooperation under sociocultural heterogeneity is higher for fishers from the village with larger institutional scope. In line with this explanation, cooperation under heterogeneity also correlates with a survey measure of individual fishers’ radius of trust. We discuss implications for resource governance and collective action research.

Analyzing potential effects of migration on coastal resource conservation in Southeastern Ghana

Coastal areas are under increasing pressure from rapid human population growth, yet empirical research on the effect of migration on coastal and marine resources is scarce. We contribute to this understudied literature by conducting an original household survey in a coastal region of Southeastern Ghana. This study employs two proxies for pro-environmental behavior that have not, to our knowledge, been used in the context of coastal migration, to explicitly compare migrant and non-migrant populations. Environmental attitudes toward coastal resources and individual extraction behavior in common-pool resource (CPR) experiments have shown broad relevance in the literature to understand natural resource decision making. We found that migrants in general did not differ significantly from non-migrants in relation to their environmental attitudes or their extraction behavior in the CPR game. However, when focusing on migrant fishers only, results suggested that this subgroup was less concerned about the utilization of coastal resources than non-migrant fishers and behaved less cooperatively in the CPR experiment. These findings, though, held true only for the subgroup of fishers, and could not be found for other occupational groups. Therefore, we conclude that migrants do not per se value coastal resources less or cooperate less in CPR situations, but that socioeconomic characteristics, and particularly their occupational status and their relation to the resource, matter.

Genetic immunization with mouse thyrotrophin hormone receptor plasmid breaks self-tolerance for a murine model of autoimmune thyroid disease and Graves' orbitopathy

Experimental models of Graves' hyperthyroid disease accompanied by Graves' orbitopathy (GO) can be induced efficiently in susceptible inbred strains of mice by immunization by electroporation of heterologous human TSH receptor (TSHR) A-subunit plasmid. In this study, we report on the development of a bona fide murine model of autoimmune Graves' disease induced with homologous mouse TSHR A-subunit plasmid. Autoimmune thyroid disease in the self-antigen model was accompanied by GO and characterized by histopathology of hyperplastic glands with large thyroid follicular cells. Examination of orbital tissues showed significant inflammation in extra-ocular muscle with accumulation of T cells and macrophages together with substantial deposition of adipose tissue. Notably, increased levels of brown adipose tissue were present in the orbital tissue of animals undergoing experimental GO. Further analysis of inflammatory loci by ¹⁹ F-magnetic resonance imaging showed inflammation to be confined to orbital muscle and optic nerve, but orbital fat showed no difference in inflammatory signs in comparison to control β-Gal-immunized animals. Pathogenic antibodies induced to mouse TSHR were specific for the self-antigen, with minimal cross-reactivity to human TSHR. Moreover, compared to other self-antigen models of murine Graves' disease induced in TSHR knock-out mice, the repertoire of autoantibodies to mouse TSHR generated following the breakdown of thymic self-tolerance is different to those that arise when tolerance is not breached immunologically, as in the knock-out models. Overall, we show that mouse TSHR A-subunit plasmid immunization by electroporation overcomes tolerance to self-antigen to provide a faithful model of Graves' disease and GO.

Time Preferences and Natural Resource Extraction Behavior: An Experimental Study from Artisanal Fisheries in Zanzibar

Natural resource users face a trade-off between present and future consumption. Using harmful methods or extracting unsustainably, lowers future consumption. Therefore, it is reasonable to posit that people with higher time preferences extract more as compared to people with lower time preferences. The present study combines experimental methods and questionnaire data in order to understand the relationship between individual time preferences and fishers' extraction behavior. We elicit individual time preferences using an incentivized experiment, linking the resulting time preference measures to extraction data from a questionnaire, as well as data collected from a framed Common Pool Resource (CPR) experiment. Both the experiments and questionnaire were conducted with artisanal fishers in Zanzibar. Our findings suggest that the relationship between time preferences and CPR extraction is not as straightforward as predicted by classical economic theory. In contrast to earlier studies, we find that fishers' time preferences are negatively correlated to their extraction rates. Our surprising findings can partly be explained by the fact that higher time preferences are associated with lower investment in extraction capability (the disinvestment effect of time preferences), and by fishers´ cognitive abilities.

Axialsymmetrische magnetohydrodynamische Gleichgewichtskonfigurationen

Es werden die Bedingungen für magnetohydrodynamische Gleichgewichtskonfigurationen mit axialer Symmetrie untersucht. Das Magnetfeld wird aufgeteilt in seine meridionalen und seine toroidalen Anteile, welche durch skalare Funktionen F bzw. T beschrieben werden. Es wird gezeigt, daß der Gasdruck p und die Funktionen F und T Funktionen voneinander sein müssen. Wenn man über die Funktionen p (F) und T (F) verfügt, bekommt man eine Differentialgleichung für F. Die Fälle, in denen diese Differentialgleichung linear ist, werden betrachtet und die Differentialgleichung explizit gelöst, wenn T (F) =const ist. In einem Spezialfall werden die magnetischen Feldlinien numerisch berechnet und in einer Abbildung angegeben. Schließlich werden noch einige Bemerkungen über die Stabilität solcher Felder angefügt.

The conditions for magneto-hydrostatic equilibrium are studied in the case of axial symmetry. The magnetic field is divided into its meridional and its toroidal parts which are described by the scalar functions F and T respectively. It is shown that the gas pressure p and the functions F and T have to be functions of each other. Taking in particular p(F) and T (F) as known relations, a differential equation for F is derived. The cases in which this differential equation is linear are considered and explicitly solved if furthermore T(F) = const. In a special case, the magnetic lines of force are calculated numerically and shown in a figure. Some remarks on the stability are added.

Neutrale Ultrastrahlung von der Sonne

Es wird gezeigt, daß bei der Beschleunigung geladener Teilchen in den äußeren Teilen der Sonnenatmosphäre durch Kerntreffer von auf die Sonne zurückfliegenden Partikeln Neutronen erzeugt werden können. Obwohl die Ausbeute (Zahl der die Sonne verlassenden Neutronen / Zahl der beschleunigten geladenen Teilchen) von der Ordnung 10-2 sein mag, kann der Effekt merklich sein, da auch geladene Teilchen einer Energie unterhalb der Abschneideenergie des Erdmagnetfeldes zur Neutronenproduktion beitragen.

Die „adiabatische Invarianz“ des magnetischen Bahnmomentes geladener Teilchen

In einem Magnetfeld ist das magnetische Bahnmoment μ* eines geladenen Teilchens annähernd eine Konstante der Bewegung, wenn das Magnetfeld nur schwach variiert. Für den Spezialfall eines homogenen, zeitabhängigen Magnetfeldes wird gezeigt, daß die relative Änderung in μ* zwischen zwei verschiedenen Zuständen, in denen das Magnetfeld konstant ist, mindestens exponentiell in h/a gegen Null geht. Hierin ist α ein Maß für die relative Feldänderungsgeschwindigkeit und mit h ist die Gyro-Frequenz bezeichnet.

The magnetic moment μ of the motion of a charged particle in a magnetic field is an approximate constant of motion in moderately varying magnetic fields. For the special case of a homgeneous time-dependent magnetic field, it is shown that the relative change in μ between two different states of constant field decreases at least exponentially in h/α if α/h tends to zero, where a represents the relative rate of change of the magnetic field and h denotes the gyro-frequency.

The Structure of Hydromagnetic Shock Waves

Es werden Wellen in einem quasi-neutralen Gas untersucht, das Ionen und Elektronen enthält und genügend kalt ist, so daß die thermischen Bewegungen vernachlässigt werden können. Außerdem werden Zusammenstöße zwischen den Teilchen vernachlässigt, jedoch nicht die Trägheitseffekte des elektrischen Stromes. Die nicht-linearen Gleichungen für unendlich ausgedehnte, ebene Kompressionswellen, die sich senkrecht zu einem homogenen Magnetfeld mit ungeänderter Form und Geschwindigkeit ausbreiten, werden auf eine einzige Diff.-Gl. 2. Ordnung für das Magnetfeld (oder für die Verschiebung der Teilchen senkrecht zur Ausbreitungsrichtung) zurückgeführt, vorausgesetzt, daß die Teilchenbahnen keine Schleifen bilden. Diese Diff.-Gl. wird exakt durch elliptische Funktionen gelöst. Verschiedene Kurven, die durch numerische Integration erhalten wurden, beschreiben die wesentlichen Eigenschaften der Lösungen. Außerdem werden Potenzreihen-Entwicklungen in der Amplitude α angegeben, wobei der Fehler in der Ordnung a4 ist. Die Lösungen sind entweder periodische Wellenzüge oder Einzelwellen. Alle Lösungen sind symmetrisch um die Maxima und Minima der magnetischen Feldstärke. Die Wellenlängen sind von der Größenordnung des Gyrationsradius. Die Geschwindigkeiten erstreckten sich vom Wert Null bis zum doppelten der Alfvén-Geschwindigkeit.

Es wird die Beziehung zwischen diesen Wellen und hydromagnetischen Stoßwellen im Plasma geringer, aber nicht verschwindender Häufigkeit gaskinetischer Stöße betrachtet und es wird der Schluß gezogen, daß die gesamte Stoßfront eine Dichte hat, die durch das Produkt aus der mittleren Zeit zwischen zwei gaskinetischen Stößen und der Gasgeschwindigkeit relativ zur Stoßfront bestimmt ist. Dieses Gebiet wird ausgefüllt durch Wellenzüge, deren Struktur von der Größenordnung des Gyrationsradius ist. Zwei Analoga zu den RANKINE-Hugeniot-Bedingungen werden angegeben: Eine, bei der auf beiden Seiten der Stoßfront ein Plasma der Temperatur Null mit verschiedenen Wellenzügen vorliegt; die anderen sind die üblichen magnetohydrodynamischen Stoßbedingungen, nur daß hier Bewegungen ausschließlich senkrecht zum Magnetfeld betrachtet werden. In beiden Fällen sind alle Erhaltungssätze durch die Stoßfront hindurch erfüllt, aber es scheint kein zufriedenstellender Mechanismus für die Prozesse innerhalb der Stoßfront zu existieren.

Human adaptive behavior in common pool resource systems

Overexploitation of common-pool resources, resulting from uncooperative harvest behavior, is a major problem in many social-ecological systems. Feedbacks between user behavior and resource productivity induce non-linear dynamics in the harvest and the resource stock that complicate the understanding and the prediction of the co-evolutionary system. With an adaptive model constrained by data from a behavioral economic experiment, we show that users’ expectations of future pay-offs vary as a result of the previous harvest experience, the time-horizon, and the ability to communicate. In our model, harvest behavior is a trait that adjusts to continuously changing potential returns according to a trade-off between the users’ current harvest and the discounted future productivity of the resource. Given a maximum discount factor, which quantifies the users’ perception of future pay-offs, the temporal dynamics of harvest behavior and ecological resource can be predicted. Our results reveal a non-linear relation between the previous harvest and current discount rates, which is most sensitive around a reference harvest level. While higher than expected returns resulting from cooperative harvesting in the past increase the importance of future resource productivity and foster sustainability, harvests below the reference level lead to a downward spiral of increasing overexploitation and disappointing returns.

Erythromycin resistance-conferring plasmid pRSB105, isolated from a sewage treatment plant, harbors a new macrolide resistance determinant, an integron-containing Tn402-like element, and a large region of unknown function

The erythromycin resistance plasmid pRSB105 was previously isolated from an activated sludge bacterial community of a municipal wastewater treatment plant. Compilation of the complete pRSB105 nucleotide sequence revealed that the plasmid is 57,137 bp in size and has a mean G+C content of 56.66 mol%. The pRSB105 backbone is composed of two different replication and/or partitioning modules and a functional mobilization region encoding the mobilization genes mobCDE and mobBA. The first replicon (Rep1) is nearly identical to the corresponding replication module of the multiresistance plasmid pRSB101 isolated from an unknown activated sludge bacterium. Accordingly, pRSB101 and pRSB105 are sister plasmids belonging to a new plasmid family. The second replicon (Rep2) of pRSB105 was classified as a member of the IncP-6 group. While Rep1 confers replication ability only in gamma-proteobacteria, Rep2 extents the host range of the plasmid since it is also functional in the beta-proteobacterium Ralstonia eutropha. Plasmid pRSB105 harbors the macrolide resistance genes mel and mph, encoding, respectively, a predicted ABC-type efflux permease and a macrolide-2'-phosphotransferase. Erythromycin resistance is mainly attributed to mel, whereas mph contributes to erythromycin resistance to a lesser extent. The second resistance region, represented by an integron-containing Tn402-like element, includes a beta-lactam (oxa10) and a trimethoprim (dfrB2) resistance gene cassette. In addition to antibiotic resistance modules, pRSB105 encodes a functional restriction/modification system and two nonresistance regions of unknown function. The presence of different mobile genetic elements that flank resistance and nonresistance modules on pRSB105 indicates that these elements were involved in acquisition of accessory plasmid modules. Comparative genomics of pRSB105 and related plasmids elucidated that pRSB105 evolved by integration of distinct modules from different plasmid sources, including Pseudomonas aeruginosa plasmids, and thus represents a mosaic plasmid.

Sequence analysis of the 144-kilobase accessory plasmid pSmeSM11a, isolated from a dominant Sinorhizobium meliloti strain identified during a long-term field release experiment

The genome of Sinorhizobium meliloti type strain Rm1021 consists of three replicons: the chromosome and two megaplasmids, pSymA and pSymB. Additionally, many indigenous S. meliloti strains possess one or more smaller plasmids, which represent the accessory genome of this species. Here we describe the complete nucleotide sequence of an accessory plasmid, designated pSmeSM11a, that was isolated from a dominant indigenous S. meliloti subpopulation in the context of a long-term field release experiment with genetically modified S. meliloti strains. Sequence analysis of plasmid pSmeSM11a revealed that it is 144,170 bp long and has a mean G+C content of 59.5 mol%. Annotation of the sequence resulted in a total of 160 coding sequences. Functional predictions could be made for 43% of the genes, whereas 57% of the genes encode hypothetical or unknown gene products. Two plasmid replication modules, one belonging to the repABC replicon family and the other belonging to the plasmid type A replicator region family, were identified. Plasmid pSmeSM11a contains a mobilization (mob) module composed of the type IV secretion system-related genes traG and traA and a putative mobC gene. A large continuous region that is about 42 kb long is very similar to a corresponding region located on S. meliloti Rm1021 megaplasmid pSymA. Single-base-pair deletions in the homologous regions are responsible for frameshifts that result in nonparalogous coding sequences. Plasmid pSmeSM11a carries additional copies of the nodulation genes nodP and nodQ that are responsible for Nod factor sulfation. Furthermore, a tauD gene encoding a putative taurine dioxygenase was identified on pSmeSM11a. An acdS gene located on pSmeSM11a is the first example of such a gene in S. meliloti. The deduced acdS gene product is able to deaminate 1-aminocyclopropane-1-carboxylate and is proposed to be involved in reducing the phytohormone ethylene, thus influencing nodulation events. The presence of numerous insertion sequences suggests that these elements mediated acquisition of accessory plasmid modules.

Rationalizing risk

This article examines the centrality of 'safety' in Grangemouth's recent politics. Scotland's main petrochemical center is a town dominated for well over fifty years by a major BP complex. In a context of extensive redundancies at BP, new insecurities surrounding the future of the company's Grangemouth site, and a series of recent accidents, as well as controversy over planning applications from other chemical companies, the town has been pushed into unusually searching questioning about both safety and economic security. This article explores the different lines of reasoning and rationalization on risk, safety, and the future advanced by regulators, BP, and residents and their political representatives. We emphasize how important the familiarity of petrochemical technology has been in public responses to the question of safety, in contrast to many environmental risk controversies. And we argue that safety has provided a focus for social, moral, economic, and political perspectives on the town's present circumstances and future prospects to be played out.

The complete sequences of plasmids pB2 and pB3 provide evidence for a recent ancestor of the IncP-1beta group without any accessory genes

The nucleotide sequences of the broad-host-range antibiotic resistance plasmids pB2 (61 kb) and pB3 (56 kb), which were isolated from a wastewater treatment plant, were determined and analysed. Both have a nearly identical IncP-1beta backbone, which diverged early from the sequenced IncP-1beta plasmids R751, pB10, pJP4, pADP1 and pUO1. In contrast to the latter plasmids, the pB2 and pB3 backbone does not seem to have undergone any deletions. The complete partition gene parA is located downstream of the mating pair formation (trb) module. A 14.4 kb or 19.0 kb mobile genetic element is present between traC and parA of pB3 and pB2, respectively. This region is typical for insertions in IncP-1beta plasmids, but the insertion site is unique. Both elements differ only by a duplication in pB2 of a tetA(C)-tetR-tnpA(IS26) fragment. The 5 bp target site duplication and the 26 bp inverted repeats flanking the mobile genetic elements are still intact, indicating that the insertion occurred recently. The element consists of three nested transposable elements: (i) a relict of a Tn402-like transposon with a gene for a new class D beta-lactamase (bla(NPS-2)); (ii) within that, another Tn402-like element with a class 1 integron harbouring the gene cassettes cmlA1 for a chloramphenicol efflux protein and aadA2 encoding a streptomycin/spectinomycin adenylyltransferase, and a copy of IS6100; (iii) into the integrase gene intI1 a tetracycline resistance module tetA(C)-tetR flanked by copies of IS26 is inserted. Interestingly, in contrast to all other IncP-1beta plasmids analysed so far, the oriV region between trfA and klcA is not interrupted by accessory genes, and there is no indication that previously inserted accessory genes have subsequently been deleted. The genes kluAB are also missing in that region and should thus be considered acquired genes. These findings, together with the fact that IncP-1beta plasmids acquired accessory elements at various positions in the backbone, suggest that IncP-1beta plasmids without any accessory genes exist in microbial communities. They must occasionally acquire accessory genes by transposition events, resulting in those plasmids that have been found based on selectable phenotypic traits.

The 120 592 bp IncF plasmid pRSB107 isolated from a sewage-treatment plant encodes nine different antibiotic-resistance determinants, two iron-acquisition systems and other putative virulence-associated functions

The antibiotic-multiresistance IncF plasmid pRSB107 was isolated by a transformation-based approach from activated-sludge bacteria of a wastewater-treatment plant. It confers resistance to ampicillin, penicillin G, chloramphenicol, erythromycin, kanamycin, neomycin, streptomycin, sulfonamides, tetracycline and trimethoprim and against mercuric ions. Complete sequencing of this plasmid revealed that it is 120 592 bp in size and has a G+C content of 53.1 mol%. The plasmid backbone is composed of three replicons, RepFIA, RepFIB and RepFII, which are almost identical to corresponding regions located on the F-plasmid and on R100. The three replicons encode replication initiation (rep) and replication control, multimer resolution (mrs), post-segregational killing of plasmid-free cells (psk) and active plasmid partitioning (sopABC locus). Part of the F-leading region and remnants of the F-homologous DNA-transfer (tra) module complete the pRSB107 backbone. Plasmid pRSB107 contains a complex, highly mosaic 35 991 bp antibiotic-resistance region consisting of a Tn21- and a Tn10-derivative and a chloramphenicol-resistance module. The Tn21 derivative is composed of a mercury-resistance region (mer), a Tn4352B-like kanamycin/neomycin-resistance transposon, a streptomycin/sulfonamide-resistance module, remnants of the beta-lactam-resistance transposon Tn1, a macrolide-resistance module flanked by copies of IS26 and IS6100, remnants of Tn402 integrating a class 1 integron and the Tn21-specific transposition module. A truncated version of the tetracycline-resistance transposon Tn10 and the chloramphenicol acetyltransferase gene catA complete the pRSB107 resistance region. In addition to antibiotic resistance, pRSB107 encodes the following putative virulence-associated functions: (i) an aerobactin iron-acquisition siderophore system (iuc/iut); (ii) a putative high-affinity Fe(2+) uptake system which was previously identified on a pathogenicity island of Yersinia pestis and in the genome of the phytopathogen Erwinia carotovora subsp. atroseptica SCRI1043; (iii) an sn-glycerol-3-phosphate transport system (ugp); and (iv) the virulence-associated genes vagCD having a possible function in stable plasmid inheritance. All the accessory modules are framed by insertion sequences, indicating that pRSB107 was gradually assembled by integration of different horizontally acquired DNA segments via transposition or homologous recombination.

Serial magnet resonance angiography in patients with vasculitis and vasculitis-like angiopathy of the central nervous system

The purpose of the study was to examine the value of the non-invasive magnet resonance angiography (MRA) in the follow-up of cerebral vasculitis (CV) and vasculitis-like angiopathy. We performed follow-up MRA (TOF 3D), MRI and transcranial doppler ultrasound (TCD) in the patients with isolated angiitis of the CNS (2/6), Crohn-disease-associated CV (1/6), and reversible arterial vasoconstriction (RAV) of the CNS (1 migraine, 1 eclampsia and 1 toxic encephalopathy) (3/6). In all patients with RAV MRA showed a complete remission of the vascular alterations after treatment. In the patients with isolated angiitis of the CNS and Crohn-disease-associated CV, partly regressive and partly progressive changes were demonstrated. The MR-angiographically detectable vascular alterations corresponded to the clinical course of the disease, as well as to TCD in all our patients. Success of therapeutic procedures, the need and the intensity of further drug administration could be estimated. The MRA appears to be a valuable non-invasive method in the follow-up of patients with CV and RAV.

[Avellis' syndrome in brainstem infarctions]

In 1891 Georg Avellis described a so-called "laryngeal hemiplegia" that can be caused by peripheral lesions of the vagal and glossopharyngeal nerves and rarely by infarctions of the medulla oblongata, thus representing a classical brainstem syndrome. In this study we describe two patients with an Avellis' syndrome caused by brainstem ischemia. Contemporary publications about Avellis' syndrome in brainstem lesions seem to be very inhomogenous. They report various diseases with unilateral laryngeal palsy due to nucleus ambiguus lesions with diverse additional neurological symptoms. We conclude that according to Avellis' original description only the combination of ipsilateral palatolaryngeal paresis and contralateral hemiparesis and/or hemihypesthesia should to be interpreted as Avellis' syndrome.

The 64 508 bp IncP-1beta antibiotic multiresistance plasmid pB10 isolated from a waste-water treatment plant provides evidence for recombination between members of different branches of the IncP-1beta group

The complete 64508 bp nucleotide sequence of the IncP-1beta antibiotic-resistance plasmid pB10, which was isolated from a waste-water treatment plant in Germany and mediates resistance against the antimicrobial agents amoxicillin, streptomycin, sulfonamides and tetracycline and against mercury ions, was determined and analysed. A typical class 1 integron with completely conserved 5' and 3' segments is inserted between the tra and trb regions. The two mobile gene cassettes of this integron encode a beta-lactamase of the oxacillin-hydrolysing type (Oxa-2) and a gene product of unknown function (OrfE-like), respectively. The pB10-specific gene load present between the replication module (trfA1) and the origin of vegetative replication (oriV) is composed of four class II (Tn3 family) transposable elements: (i). a Tn501-like mercury-resistance (mer) transposon downstream of the trfA1 gene, (ii). a truncated derivative of the widespread streptomycin-resistance transposon Tn5393c, (iii). the insertion sequence element IS1071 and (iv). a Tn1721-like transposon that contains the tetracycline-resistance genes tetA and tetR. A very similar Tn501-like mer transposon is present in the same target site of the IncP-1beta degradative plasmid pJP4 and the IncP-1beta resistance plasmid R906, suggesting that pB10, R906 and pJP4 are derivatives of a common ancestor. Interestingly, large parts of the predicted pB10 restriction map, except for the tetracycline-resistance determinant, are identical to that of R906. It thus appears that plasmid pB10 acquired as many as five resistance genes via three transposons and one integron, which it may rapidly spread among bacterial populations given its high promiscuity. Comparison of the pB10 backbone DNA sequences with those of other sequenced IncP-1beta plasmids reveals a mosaic structure. While the conjugative transfer modules (trb and tra regions) and the replication module are very closely related to the corresponding segments of the IncP-1beta resistance plasmid R751 and even more similar to the IncP-1beta degradative plasmids pTSA and pADP-1, the stable inheritance operons klcAB-korC and kleAEF are most similar to those of the IncP-1beta resistance plasmid pB4, and clearly less similar to the other IncP-1beta plasmids. This suggests that IncP-1beta plasmids can undergo recombination in the environment, which may enhance plasmid diversity and bacterial adaptability.

[Morphologic carotid plaque characteristics in symptomatic and asymptomatic patients on MRI compared to histopathologic and macroscopic criteria]

INTRODUCTION

The morphologic concept of unstable high-risk-plaques is gaining importance for the decision on invasive therapy of carotid stenoses. Plaque morphology was investigated with MRI in vitro and in vivo with regard to limited diagnostic means.

METHODS

Carotid stenoses of 12 patients were scanned with 1.5-T MRI preoperatively in vivo, as was the bifurcation plaque after the operation. The scans were compared with the histologic sections ( n=5) and opened plaques ( n=7).

RESULTS

The MR morphology was identified corresponding to histologic sections. The hyperintense necrotic core and hypointense fibrous cap (T2) were well defined. Due to moving artefacts, in vivo MRIs were less accurate.

CONCLUSION

The histomorphology of carotid plaques with necrotic core and fibrous cap, basic for understanding the concept of unstable high-risk plaques, is presented on MRI in vitro and in vivo. Further clinical studies should follow.

The 79,370-bp conjugative plasmid pB4 consists of an IncP-1beta backbone loaded with a chromate resistance transposon, the strA-strB streptomycin resistance gene pair, the oxacillinase gene bla(NPS-1), and a tripartite antibiotic efflux system of the resistance-nodulation-division family

Plasmid pB4 is a conjugative antibiotic resistance plasmid, originally isolated from a microbial community growing in activated sludge, by means of an exogenous isolation method with Pseudomonas sp. B13 as recipient. We have determined the complete nucleotide sequence of pB4. The plasmid is 79,370 bp long and contains at least 81 complete coding regions. A suite of coding regions predicted to be involved in plasmid replication, plasmid maintenance, and conjugative transfer revealed significant similarity to the IncP-1beta backbone of R751. Four resistance gene regions comprising mobile genetic elements are inserted in the IncP-1beta backbone of pB4. The modular 'gene load' of pB4 includes (1) the novel transposon Tn 5719 containing genes characteristic of chromate resistance determinants, (2) the transposon Tn 5393c carrying the widespread streptomycin resistance gene pair strA-strB, (3) the beta-lactam antibiotic resistance gene bla(NPS-1) flanked by highly conserved sequences characteristic of integrons, and (4) a tripartite antibiotic resistance determinant comprising an efflux protein of the resistance-nodulation-division (RND) family, a periplasmic membrane fusion protein (MFP), and an outer membrane factor (OMF). The components of the RND-MFP-OMF efflux system showed the highest similarity to the products of the mexCD-oprJ determinant from the Pseudomonas aeruginosa chromosome. Functional analysis of the cloned resistance region from pB4 in Pseudomonas sp. B13 indicated that the RND-MFP-OMF efflux system conferred high-level resistance to erythromycin and roxithromycin resistance on the host strain. This is the first example of an RND-MFP-OMF-type antibiotic resistance determinant to be found in a plasmid genome. The global genetic organization of pB4 implies that its gene load might be disseminated between bacteria in different habitats by the combined action of the conjugation apparatus and the mobility of its component elements.

The chlorophyll-derived metabolite phytanic acid induces white adipocyte differentiation

Phytanic acid is a derivative of the phytol side-chain of chlorophyll. It appears in humans following the ingestion of fat-containing foods and is present in human blood at a low micromolar concentration. It may activate retinoid X receptors (RXR) or peroxisome proliferator-activated receptor (PPAR) alpha in vitro. Phytanic acid induced the adipocyte differentiation of 3T3-L1 cells in culture as assessed by accumulation of lipid droplets and induction of the aP2 mRNA marker. This effect was mimicked by a synthetic activator of RXR but not by a PPARalpha agonist or by palmitic acid. In human pre-adipocytes in primary culture, phytanic acid also induced adipocyte differentiation. These findings indicate that phytanic acid may act as a natural rexinoid in adipose cells and suggest a potential use in the treatment of human type 2 diabetes and obesity.

Characterisation of Phaseolus symbionts isolated from Mediterranean soils and analysis of genetic factors related to pH tolerance

The ultimate objective of PhIMED, in which two European (Germany, Italy) and two Mediterranean (Morocco, Egypt) countries collaborate, is to improve the cultivation of French bean (Phaseolus vulgaris) under arid and semi-arid conditions by analysing and enhancing stress tolerance of the nitrogen fixing rhizobial microsymbionts. Rhizobial strains nodulating P. vulgaris (RP strains) isolated from areas in Morocco frequently subjected to drought were analysed for their salt and pH tolerance and their phylogenetic relationship. Strain RP163, exhibiting high nodulation efficiency and a broad pH tolerance was mutagenised by Tn5 and mutants unable to grow on extreme pH media were isolated. Some of the mutants affected in low pH tolerance were found to be mutated in genes related to cobalmin biosynthesis and in succinate dehydrogenase (sdhA). In a parallel approach, promoters and genes inducible under extreme pH values were identified in Rhizobium leguminosarum bv. viciae VF39, among them gabT, which encodes the GABA transaminase and which is induced under acidic conditions. The same gene is present and similarly regulated in RP163. The actSR gene region was cloned from VF39, sequenced and mutants generated in this region were found to be impaired in growth at low pH, but also under neutral conditions. The Agrobacterium rhizogenes 'promintron' promoter, reported to be activated in stationary phase, was found to be also strongly induced under acidic conditions in rhizobia and it is currently being characterised to construct a system allowing the expression of stress tolerance genes in bacteroids and free-living bacteria.

[MR angiography in diagnosis of vasculitis and benign angiopathies of the central nervous system]

PURPOSE

To evaluate TOF 3D magnetic resonance angiography (MRA) of the intracranial arteries in patients with vasculitis or vasculitis-like benign angiopathy of the central nervous system (CNS).

METHOD

The results of MRA in 20 patients with clinically and radiographically proven vasculitis (17/20) or vasculitis-like benign angiopathy (3/20) of the CNS were retrospectively analysed. Patients with hyperintense lesions of more than 3 mm on T2-weighted MRI images were included in this trial. An inflammatory, embolic, neurodegenerative or metastatic origin of these lesions was excluded by extensive clinical studies. For the MR-examination a TOF 3D FISP sequence was used on a 1.5 T imager.

RESULTS

MRA showed characteristic changes for vasculitis or angiopathy in 15 of 20 patients (75%).

CONCLUSIONS

In patients suspected of having a vasculitis or vasculitis-like angiopathy, MRA is recommended as a non-invasive modality. If the results of MRI and extensive clinical studies are carefully correlated, MRA may substitute conventional angiography in cases with typical vascular changes.

Expression and subcellular localization of cpn60 protein family members in Leishmania donovani

We have identified two diverged members of the cpn60 gene family in Leishmania donovani, causative agent of Indian Kala Azar. One of the genes, cpn60.1, although actively transcribed, is not expressed to detectable levels of protein in cultured L. donovani. The other gene, cpn60.2, which, compared with cpn60.1, shows a higher sequence conservation with the hsp60 genes from Trypanosoma brucei and Trypanosoma cruzi is expressed constitutively in cultured promastigotes. The abundance of the gene product, Cpn60.2, increases by 2.5-fold under heat stress and in axenic amastigotes of L. donovani. Cpn60.2 is also found enriched in mitochondrial cell fractions and localizes to the mitochondrial matrix. We conclude that Cpn60.2 is the major mitochondrial chaperonin in Leishmania.

[Radiological evaluation of complications of implantable venous access port systems]

OBJECTIVE

Clinical signs and symptoms sometimes throw suspicion on functional complications and venous thrombosis due to implantable venous access ports. Objective was to determine frequency of these problems using radiologic imaging.

METHODS

61 patients were examined by means of fluoroscopy. If indication was given we injected radiopaque (contrast) medium. In the case of suspected vascular thrombosis the radiological finding was verified by sonography, phlebography or by venous magnetic resonance imaging angiography.

RESULTS

Altogether 46 complications were documented in 37 out of 61 examined patients (61%). Occlusions of port-catheter were proved in 24 cases. It was the radiologically most frequently recorded complication (52%;) and found coincident with other problems in 9 patients (37%;). Pain frequently indicates break of catheters. Implantation of catheters into jugular and axillary veins predisposes to break of catheters just as port-catheters lateral implanted into subclavian veins ("pinch-off-sign").

CONCLUSIONS

Functional tests of venous access systems using fluoroscopy and phlebography give information that helps to decide if clinically problematic port-systems should be used furthermore. Directions of catheter which are predestined to complications should be avoided.

Functional and regulatory analysis of the two copies of the fixNOQP operon of Rhizobium leguminosarum strain VF39

DNA corresponding to two copies of the Rhizobium leguminosarum bv. viciae strain VF39 fixNOQP operon coding for a putative symbiotic terminal oxidase of the heme-copper oxidase superfamily was cloned, sequenced, and genetically analyzed. The first copy is located upstream of the fixK-fixL region on plasmid pRleVF39c, whereas the second copy resides on the nodulation plasmid pRleVF39d. Insertional mutagenesis with antibiotic resistance cassettes confirmed that both copies were functional, and that the presence of at least one functional copy was required for nitrogen fixation. The deduced amino acid sequences of both fixN genes are highly similar (95% identity) and contain 15 putative transmembrane helices, suggesting that the fixN gene products are integral membrane proteins. Furthermore, six histidine residues predicted to be the ligands for a heme-copper binuclear center and a low-spin heme b are conserved in both R. leguminosarum fixN proteins. The deduced fixO and fixP gene products show characteristics of membrane-bound monoheme and diheme cytochrome c, respectively. Upstream of both fixN copies putative Fnr-consensus binding sites (anaeroboxes) were found that differ in certain base pairs. As R. leguminosarum VF39 possesses two members of the Fnr/FixK regulator family, FnrN and FixK, the possible differential regulation of both fixN copies was analyzed with fixN-gusA reporter gene fusions. Both fixN fusions were induced under free-living microaerobic conditions and in the symbiotic zone of the root nodule. Induction of the expression of fixNc and fixNd was highly reduced in a fnrN mutant background and in a fixL mutant background, whereas fixK was only marginally involved in fixN regulation. Residual expression of fixN was observed in an fnrN/fixK double mutant.