Preemptive treatment approach to cytomegalovirus (CMV) infection in solid organ transplant patients: relationship between compliance with the guidelines and prevention of CMV morbidity.

Cytomegalovirus (CMV) remains a major cause of morbidity in solid organ transplant patients. In order to reduce CMV morbidity, we designed a program of routine virological monitoring that included throat and urine CMV shell vial culture, along with peripheral blood leukocyte (PBL) shell vial quantitative culture for 12 weeks post-transplantation, as well as 8 weeks after treatment for acute rejection. The program also included preemptive ganciclovir treatment for those patients with the highest risk of developing CMV disease, i.e., with either high-level viremia (>10 infectious units [IU]/106 PBL) or low-level viremia (<10 IU/106 PBL) and either D+/R- CMV serostatus or treatment for graft rejection. During 1995-96, 90 solid organ transplant recipients (39 kidneys, 28 livers, and 23 hearts) were followed up. A total of 60 CMV infection episodes occurred in 45 patients. Seventeen episodes were symptomatic. Of 26 episodes managed according to the program, only 4 presented with CMV disease and none died. No patient treated preemptively for asymptomatic infection developed disease. In contrast, among 21 episodes managed in non-compliance with the program (i.e., the monitoring was not performed or preemptive treatment was not initiated despite a high risk of developing CMV disease), 12 episodes turned into symptomatic infection (P=0.0048 compared to patients treated preemptively), and 2 deaths possibly related to CMV were recorded. This difference could not be explained by an increased proportion of D+/R- patients or an increased incidence of rejection among patients with episodes treated in non-compliance with the program. Our data identify compliance with guidelines as an important factor in effectively reducing CMV morbidity through preemptive treatment, and suggest that the complexity of the preemptive approach may represent an important obstacle to the successful prevention of CMV morbidity by this approach in the regular healthcare setting.

High precision U/Pb zircon dating of the Chalten Plutonic Complex (Cerro Fitz Roy, Patagonia) and its relationship to arc migration in the southernmost Andes

We report new high-precision U/Pb ages and geochemical data from the Chalten Plutonic Complex to better understand the link between magmatism and tectonics in Southern Patagonia. This small intrusion located in the back-arc region east of the Patagonian Batholith provides important insights on the role of arc migration and subduction erosion. The Chalten Plutonic Complex consists of a suite of calc-alkaline gabbroic to granitic rocks, which were emplaced over 530 kyr between 16.90 +/- 0.05 Ma and 16.37 +/- 0.02 Ma. A synthesis of age and geochemical data from other intrusions in Patagonia reveals (a) striking similarities between the Chalten Plutonic Complex and the Neogene intrusions of the batholith and differences to other back-arc intrusions such as Torres del Paine (b) a distinct E-W trend of calc-alkaline magmatic activity between 20 and 17 Ma. We propose that this trend reflects the eastward migration of the magmatic arc, and the consistent age pattern between the subduction segments north and south of the Chile triple junction suggests a causal relation with a period of fast subduction of the Farallon-Nazca plate during the Early Miocene. Previously proposed flat slab models are not consistent with the present location and morphology of the Southern Patagonian Batholith. We advocate, alternatively, that migration of the magmatic arc is caused by subduction erosion due to the increasing subduction velocities during the Early Miocene.

Trace element chemistry and U-Pb dating of zircons from oceanic gabbros and their relationship with whole rock composition (Lanzo, Italian Alps)

The U-Pb ages and the trace element content of zircon U-Pb along with major and trace element whole rock data on gabbroic dikes from the Lanzo lherzolitic massif, N-Italy, have been determined to constrain crustal accretion in ocean-continent transition zones. Three Fe-Ti gabbros were dated from the central and the southern part of the massif providing middle Jurassic ages of 161 +/- 2, 158 +/- 2 and 163 +/- 1 Ma, which argue for magmatic activity over few millions of years. Zircon crystals are characterized by high but variable Th/U ratios, rare earth element patterns enriched in heavy rare earths, pronounced positive Ce and negative Eu-anomalies consistent with crystallization after substantial plagioclase fractionation. The zircon trace element composition coupled with whole rock chemistry was used to reconstruct the crystallization history of the gabbros. A number of gabbros crystallized in situ, and zircon precipitated from trapped, intercumulus liquid, while other gabbros represent residual liquids that were extracted from a cumulus pile and crystallized along syn-magmatic shear zones. We propose a model in which the emplacement mechanism of gabbroic rocks in ocean-continent transition zones evolves from in situ crystallization to stratified crystallization with efficient extraction of residual liquid along syn-magmatic shear zones. Such an evolution of the crystallization history is probably related to the thermal evolution of the underlying mantle lithosphere.

Investigating the relationship between pollination strategies and the size-advantage model in zoophilous plants using the reproductive biology of Arum cylindraceum and other European Arum species as case studies

The size-advantage model (SAM) explains the temporal variation of energetic investment on reproductive structures (i.e. male and female gametes and reproductive organs) in long-lived hermaphroditic plants and animals. It proposes that an increase in the resources available to an organism induces a higher relative investment on the most energetically costly sexual structures. In plants, pollination interactions are known to play an important role in the evolution of floral features. Because the SAM directly concerns flower characters, pollinators are expected to have a strong influence on the application of the model. This hypothesis, however, has never been tested. Here, we investigate whether the identity and diversity of pollinators can be used as a proxy to predict the application of the SAM in exclusive zoophilous plants. We present a new approach to unravel the dynamics of the model and test it on several widespread Arum (Araceae) species. By identifying the species composition, abundance and spatial variation of arthropods trapped in inflorescences, we show that some species (i.e. A. cylindraceum and A. italicum) display a generalist reproductive strategy, relying on the exploitation of a low number of dipterans, in contrast to the pattern seen in the specialist A. maculatum (pollinated specifically by two fly species only). Based on the model presented here, the application of the SAM is predicted for the first two and not expected in the latter species, those predictions being further confirmed by allometric measures. We here demonstrate that while an increase in the female zone occurs in larger inflorescences of generalist species, this does not happen in species demonstrating specific pollinators. This is the first time that this theory is both proposed and empirically tested in zoophilous plants. Its overall biological importance is discussed through its application in other non-Arum systems.

Reexamination of the relationship of resting metabolic rate to fat-free mass and to the metabolically active components of fat-free mass in humans.

The ratio of resting metabolic rate (RMR) to fat-free mass (FFM) is often used to compare individuals of different body sizes. Because RMR has not been well described over the full range of FFM, a literature review was conducted among groups with a wide range of FFM. It included 31 data sets comprising a total of 1111 subjects: 118 infants and preschoolers, 323 adolescents, and 670 adults; FFM ranged from 2.8 to 106 kg. The relationship of RMR to FFM was found to be nonlinear and average slopes of the regression equations of the three groups differed significantly (P less than 0.0001). For only the youngest group did the intercept approach zero. The lower slopes of RMR on FFM, at higher measures of FFM, corresponded to relatively greater proportions of less metabolically active muscle mass and to lesser proportions of more metabolically active nonmuscle organ mass. Because the contribution of FFM to RMR is not constant, an arithmetic error is introduced when the ratio of RMR to FFM is used. Hence, alternative methods should be used to compare individuals with markedly different FFM.

Transnational private authority and the participation of workers' organizations in the regulatory space surrounding the employment relationship

Most corporate codes of conduct and multi-stakeholder sustainability standards guarantee workers' rights to freedom of association and collective bargaining, but many authors are sceptical about the concrete impact of codes and standards of this kind. In this paper we use Hancher and Moran's (1998) concept of 'regulatory space' to assess the potential of private transnational regulation to support the growth of trade union membership and collective bargaining relationships, drawing on some preliminary case study results from a project on the impact of the International Finance Corporation's (IFC) social conditionality on worker organization and social dialogue. One of the major effects of neoliberal economic and industrial policy has been the routine exclusion of workers' organizations from regulatory processes on the grounds that they introduce inappropriate 'political' motives into what ought to be technical decision-making processes. This, rather than any direct attack on their capacity to take action, is what seems best to explain the global decline in union influence (Cradden 2004; Howell 2007; Howe 2012). The evidence we present in the paper suggests that private labour regulation may under certain conditions contribute to a reversal of this tendency, re-establishing the legitimacy of workers' organizations within regulatory processes and by extension the legitimacy of their use of economic and social power. We argue that guarantees of freedom of association and bargaining rights within private regulation schemes are effective to the extent that they can be used by workers' organizations in support of a claim for access to the regulatory space within which the terms and conditions of the employment relationship are determined. Our case study evidence shows that certain trade unions in East Africa have indeed been able to use IFC and other private regulation schemes as levers to win recognition from employers and to establish collective bargaining relationships. Although they did not attempt to use formal procedures to make a claim for the enforcement of freedom of association rights on behalf of their members, the unions did use enterprises' adherence to private regulation schemes as a normative point of reference in argument and political exchange about worker representation. For these unions, the regulation was a useful addition to the range of arguments that they could deploy as means to justify their demand for recognition by employers. By contrast, the private regulation that helps workers' organizations to win access to regulatory processes does little to ensure that they are able to participate meaningfully, whether in terms of technical capacity or of their ability to mobilize social power as a counterweight to the economic power of employers. To the extent that our East African unions were able to make an impact on terms and conditions of employment via their participation in regulatory space it was solely on the basis of their own capacities and resources and the application of national labour law.

Is the relationship between major depressive disorder and self-reported alcohol use disorder an artificial one ?

AIMS: Many studies have suggested a close relationship between alcohol use disorder (AUD) and major depressive disorder (MDD). This study aimed to test whether the relationship between self-reported AUD and MDD was artificially strengthened by the diagnosis of MDD. This association was tested comparing relationships between alcohol use and AUD for depressive people and non-depressive people. METHODS: As part of the Cohort Study on Substance Use Risk Factors, 4352 male Swiss alcohol users in their early twenties answered questions concerning their alcohol use, AUD and MDD at two time points. Generalized linear models for cross-sectional and longitudinal associations were calculated. RESULTS: For cross-sectional associations, depressive participants reported a higher number of AUD symptoms (β = 0.743, P < 0.001) than non-depressive participants. Moreover, there was an interaction (β = -0.204, P = 0.001): the relationship between alcohol use and AUD was weaker for depressive participants rather than non-depressive participants. For longitudinal associations, there were almost no significant relationships between MDD at baseline and AUD at follow-up, but the interaction was still significant (β = -0.249, P < 0.001). CONCLUSION: MDD thus appeared to be a confounding variable in the relationship between alcohol use and AUD, and self-reported measures of AUD seemed to be overestimated by depressive people. This result brings into question the accuracy of self-reported measures of substance use disorders. Furthermore, it adds to the emerging debate about the usefulness of substance use disorder as a concept, when heavy substance use itself appears to be a sensitive and reliable indicator.