Author Correction: Climatic controls of decomposition drive the global biogeography of forest-tree symbioses.

In this Letter, a middle initial and additional affiliation have been added for author G. J. Nabuurs; two statements have been added to the Supplementary Acknowledgements; and a citation to the French National Institute has been added to the Methods; see accompanying Author Correction for further details.

Climatic controls of decomposition drive the global biogeography of forest-tree symbioses.

The identity of the dominant root-associated microbial symbionts in a forest determines the ability of trees to access limiting nutrients from atmospheric or soil pools1,2, sequester carbon3,4 and withstand the effects of climate change5,6. Characterizing the global distribution of these symbioses and identifying the factors that control this distribution are thus integral to understanding the present and future functioning of forest ecosystems. Here we generate a spatially explicit global map of the symbiotic status of forests, using a database of over 1.1 million forest inventory plots that collectively contain over 28,000 tree species. Our analyses indicate that climate variables-in particular, climatically controlled variation in the rate of decomposition-are the primary drivers of the global distribution of major symbioses. We estimate that ectomycorrhizal trees, which represent only 2% of all plant species7, constitute approximately 60% of tree stems on Earth. Ectomycorrhizal symbiosis dominates forests in which seasonally cold and dry climates inhibit decomposition, and is the predominant form of symbiosis at high latitudes and elevation. By contrast, arbuscular mycorrhizal trees dominate in aseasonal, warm tropical forests, and occur with ectomycorrhizal trees in temperate biomes in which seasonally warm-and-wet climates enhance decomposition. Continental transitions between forests dominated by ectomycorrhizal or arbuscular mycorrhizal trees occur relatively abruptly along climate-driven decomposition gradients; these transitions are probably caused by positive feedback effects between plants and microorganisms. Symbiotic nitrogen fixers-which are insensitive to climatic controls on decomposition (compared with mycorrhizal fungi)-are most abundant in arid biomes with alkaline soils and high maximum temperatures. The climatically driven global symbiosis gradient that we document provides a spatially explicit quantitative understanding of microbial symbioses at the global scale, and demonstrates the critical role of microbial mutualisms in shaping the distribution of plant species.

Withdrawal syndrome in the pediatric intensive care unit. Incidence and risk factors.

OBJECTIVE: To determine the incidence of withdrawal syndrome after prolonged infusion of fentanyl and midazolam in children, and the associated risk factors. DESIGN: Historic or retrospective cohort study. SETTING: Pediatric Intensive Care Unit in an academic center. PATIENTS: Forty-eight pediatric patients who received sedation and analgesia only with fentanyl and midazolam through continuous infusion for at least 48 hours. INTERVENTIONS: None. MAIN VARIABLES OF INTEREST: Collected data included demographic and clinical parameters, dose and duration of sedation received, and incidence, severity and treatment of withdrawal syndrome. RESULTS: Fifty percent of the patients developed withdrawal syndrome. There were significant differences between the patients who developed withdrawal syndrome and those who did not, in terms of the duration of infusion and the cumulative doses of both drugs. A cumulative fentanyl dose of 0.48 mg/kg, a cumulative midazolam dose of 40 mg/kg, and a duration of infusion of both drugs of 5.75 days were risk factors for the development of withdrawal syndrome. Most children developed mild or moderate disease, beginning about 12-36 hours after weaning from infusion. Methadone was used in most cases for treating withdrawal. CONCLUSIONS: There is a high incidence of withdrawal syndrome in children following the continuous infusion of midazolam and fentanyl. The duration of infusion of both drugs and higher cumulative doses are associated with the development of withdrawal syndrome.

Topical endotracheal mitomycin C as a complementary treatment for endoscopic treatment of recurrent laryngotracheal stenosis.

OBJECTIVE: To describe the preparation of topical endotracheal mitomycin C and the clinical outcomes of four patients with recurrent and severe laryngotracheal stenosis (LTS) treated with adjuvant topical mitomycin C. METHOD: Literature review to determine the concentration and method of preparation of topical mitomycin C for endotracheal use. Review of clinical histories. RESULTS: We established a concentration of 0.4 mg/ml topical mitomycin C for the treatment of laryngotracheal stenosis. In the treated cases, we applied a 0.4 mg/ml solution to the wound site following laser surgery and dilatation with bronchoscope. Three patients remain asymptomatic from a respiratory perspective, and treatment failed in one case. CONCLUSIONS: LTS treatment is complex due to the continuous development of granulation tissue and fibrosis following injury to the airways. Topical mitomycin C seems to be the ideal adjuvant agent thanks to its powerful antifibrotic effects.

Mushroom productivity trends in relation to tree growth and climate across different European forest biomes.

Although it is logical to think that mycorrhizal mushroom production should be somehow related to the growth of the trees from which the fungi obtain carbohydrates, little is known about how mushroom yield patterns are related to tree performance. In this study, we delved into the understanding of the relationships between aboveground fungal productivity, tree radial growth patterns and climatic conditions across three latitudinally different bioclimatic regions encompassing Mediterranean, temperate and boreal forest ecosystems in Europe. For this purpose, we used a large assemblage of long-term data of weekly or biweekly mushroom yield monitoring in Spain, Switzerland and Finland. We analysed the relationships between annual mushroom yield (considering both biomass and number of sporocarps per unit area), tree ring features (tree ring, earlywood and latewood widths), and meteorological conditions (i.e. precipitation and temperature of summer and autumn) from different study sites and forest ecosystems, using both standard and partial correlations. Moreover, we fitted predictive models to estimate mushroom yield from mycorrhizal and saprotrophic fungal guilds based on climatic and dendrochronological variables. Significant synchronies between mushroom yield and climatic and dendrochronological variables were mostly found in drier Mediterranean sites, while few or no significant correlations were found in the boreal and temperate regions. We observed positive correlations between latewood growth and mycorrhizal mushroom biomass only in some Mediterranean sites, this relationship being mainly mediated by summer and autumn precipitation. Under more water-limited conditions, both the seasonal wood production and the mushroom yield are more sensitive to precipitation events, resulting in higher synchrony between both variables. This comparative study across diverse European forest biomes and types provides new insights into the relationship between mushroom productivity, tree growth and weather conditions.

Subfoveal perfluorocarbon liquid. Removal after three months. / Perfluorocarbono líquido subfoveal. Extracción después de 3 meses.

CLINICAL CASE: A case of surgical removal of a subfoveal perfluorocarbon liquid (PFCL) bubble that remained trapped inside the subretinal space. PFCL bubble extraction was performed by performing a therapeutic and vacuum PFCL bubble macular retinal detachment. DISCUSSION: The elapsed time before subfoveal PFCL extraction seems to influence the visual result. There are other factors which could influence the final visual acuity significantly, nevertheless it is possible to achieve useful vision, as long as the fovea is not damaged and iatrogenic injuries are avoided during PFCL bubble extraction.

Early lymphocyte activation in elderly humans: impaired T and T-dependent B cell responses.

Immunosenescence is characterized by an increase in autoantibody production. Because both T and B cell stimulation are key events for producing antibodies, we investigated early T and B cell activation by means of CD23 and CD40L (two very early activation antigens). PBMC from elderly humans (EH) were studied following culture with either medium, anti-CD3mAb, rIL-4, or PMA + ionomycin. CD23 expression on elderly B cells after anti-CD3 challenge of PBMC, a reflect of T-dependent B cell activation, was clearly defective. Conversely, CD23 expression on EH B cells following activation with soluble factors as rIL-4 was preserved. CD40L expression was also impaired in EH T cells following anti-CD3 challenge. However, activation by means of PMA and/or ionomycin was preserved both in T cells (CD40L expression) and in B cells (CD23 expression). These results indicate that a defective T-dependent B cell activation related to defective T cell activation located between surface membrane and PKC/ionomycin function is an intrinsic characteristic of immunosenescence. We have not found intrinsic B-cell defects, and we conclude that the characteristically impaired early B cell activation in EH is mostly due to T cell defects.

Effects of alprazolam on the free-choice ethanol consumption induced by isolation stress in aged rats.

Late-onset drinking is a common problem in elderly people related to stress induced by social isolation. Experiments were performed in order to evaluate the effects of alprazolam, a benzodiazepine agonist anxiolytic, on the free-choice ethanol consumption in aged rats subjected to isolation stress. The animals we offered a two-bottle choice consumption (one of 0.2% saccharin and the other with 10% ethanol/0.2% saccharin) and then exposed to 4 days of isolation stress on an irregular, unpredictable schedule. Stress resulted in significant increase in ethanol consumption. Treatment with alprazolam (1 mg/Kg) partially reversed this adverse effect of stress.

B cell activation in rheumatoid arthritis patients under infliximab treatment.

OBJECTIVE: To determine whether anti-TNF alpha (infliximab) treatment affects B cell activation in patients with rheumatoid arthritis (RA) METHODS: B cell activation was analyzed in fifteen anti-TNF-treated RA patients. CD23 expression was used as a B cell activation marker and was studied before and after three months of infliximab treatment. PBMC were stimulated with anti-CD3 mAb during 18 h and were separated by rosseting into E+ and E-cells. B cells were assessed in E-population by double staining with CD19 and CD23. ELISA assays were used to assess both soluble TNF alpha and circulant immune complexes (CIC) containing TNF alpha. We also used B cells from tonsils to establish the relationship between B cell activation and TNF alpha CIC. RESULTS: The proportion of B cells expressing CD23 was higher before infliximab exposure than after treatment (48.3 +/- 16.7 versus 29.5 +/- 12.5, p = 0.007). T-B cell interactions were assessed by means of blocking antibodies to CD154, CD40, CD69, and CD18; these interactions were not specially affected by infliximab treatment. We could demonstrate CIC containing TNF alpha after infliximab treatment, these CIC, similarly to others IgG-containing immune complexes, were capable to downregulate CD23 on B cells. CONCLUSIONS: Infliximab treatment in RA downregulates CD23 expression on T-cell activated B cells. This downregulation is connected with the presence of CIC containing TNF alpha. Presumably, the Fc gamma RIIb1 endows IgG-containing immune complexes, as TNF alpha-anti-TNF alpha, with the capacity to regulate B cells and inflammatory cells.

[Three cases of imported dermatomycosis by Scytalidium dimidiatum]. / Dermatomicosis de importación por Scytalidium dimidiatum: a propósito de tres casos.

Scytalidium dimidiatum dermatomycosis are usually reported in tropical and subtropical countries. Some cases in Spain have been diagnosed due to the increasing number of immigrants from these areas. We herein describe three new cases of S. dimidiatum infections detected in Madrid. Two patients were from Guinea Ecuatorial and the third from Angola. We also report the first case of S. dimidiatum infection in a HIV patient in Spain. Clinical and epidemiological characteristics of S. dimidiatum infections reported in Spain are discussed.

[Chronic multifocal osteomyelitis]. / Osteomielitis crónica múltiple.

The cases of three female Guinean children are described. Bloods tests were nonspecific, showing a moderately high globular sedimentation rate. The patients received combined therapy with systemic antibiotic therapy (including local gentamicin administration in two of the three patients) and surgery. One patient returned to Guinea and was lost to follow-up. The second patient showed severe sequelae and the third patient had a favorable outcome. In recent years, the prevalence of chronic osteomyelitis in Africa has increased. Most patients have multiple bone involvement and multiple etiology. Blood cultures are negative in 40 % of patients and severe radiologic abnormalities, most commonly fractures, are frequent. A successful therapeutic regimen must be based on antibiotic and surgical treatment.

[Determinants of uremia elevation in the first days of life in premature infants born before 30 weeks of gestation]. / Factores determinantes de la elevación de la uremia en los primeros días de vida en recién nacidos con menos de 30 semanas de gestación.

OBJECTIVE: To identify the determinants associated with uremia elevation in the first days of life in extremely premature infants. METHODS: We performed a prospective cohort study in a cohort of neonates born at less than 30 weeks of gestation. RESULTS: Forty-eight preterm infants were included, of which 10 died. The mean fluid administration was 55, 72, 88 and 124 mL/kg on the first, second, third and seventh days of life. Amino acid doses were low in the first two days of life and were unrelated to uremia elevation. Thirty-one percent of the infants presented hypernatremia. Uremia was measured in 31 infants between the fifth and tenth days of life and 12 infants (38.7 %) had uremia values of 100 mg/dL or higher, without creatinine elevation. All of these infants were born at less than 27 weeks of gestation, weighed less than 850 grams at birth, and showed greater weight loss (19.2 % vs. 13.8 %; p 5 0.037) and higher natremia (150.2 mEq/L vs. 146.6 mEq/L; p 5 0.023). The use of furosemide increased the risk of elevated uremia (relative risk: 2.54; 95 % confidence interval: 1.05 6.14). CONCLUSIONS: Total uremia of 100 mg/dL or higher was associated with dehydration, greater weight loss, higher natremia, furosemide use, lower gestational age, and lower birth weight.

[Validation of the transcutaneous carbon dioxide tension measurements in critical paediatric patients]. / Validación de la medición transcutánea de la presión parcial de dióxido de carbono en el paciente crítico pediátrico.

OBJECTIVE: To estimate the accuracy of the transcutaneous carbon dioxide tension measurement (PtCO(2)) compared to the measurement of the arterial carbon dioxide tension (PaCO(2)). MATERIAL AND METHODS: An analytical, longitudinal, prospective and observational study, of a dynamic cohort taken from the in-patients of a Paediatric Intensive Care Unit (PICU). The PtCO(2) was measured with the SenTec AG analyzer, and the sensor was applied with the specific Multi-Site Attachment Ring. PtCO(2) and PaCO(2) were recorded at the same time. The statistical significance of the association between paired measurements was evaluated with the Snedecor's F test, the Pearson's r(2) correlation coefficient and the Interclass Correlation Coefficient (ICC). The degree of agreement was evaluated with the Bland & Altman method. The consistency of the results was evaluated with the ANalysis Of the VAriance (ANOVA). RESULTS: One hundred and six paired measurements, PtCO(2) and PaCO(2), from twelve patients, were compared. The means of the PaCO(2) and PtCO(2) were 51.0+/-13mmHg and 50.1+/-14mmHg, respectively; r(2)=0.87 (p<0.001), ICC=0.96, (95% CI: 0.94-0.97). The Bland-Altman analysis showed a mean difference of-0.9mmHg (95% CI:-2.0 to 0.2mmHg). The correlation was better in cases with no respiratory disease, with low respiratory assistance, with PaCO(2)>50mmHg and with the sensor applied on the forehead. The results were consistent. No side effects derived from the use of the ring were observed. CONCLUSION: The correlation between PtCO(2) and PaCO(2) is excellent and stable. The ring sensor was safe and easy to use.

Potential relationship between herpes viruses and rheumatoid arthritis: analysis with quantitative real time polymerase chain reaction.

OBJECTIVE: To determine whether the human herpes viruses, cytomegalovirus (CMV), Epstein-Barr virus (EBV), and human herpesvirus 6 (HHV-6), are detectable in serum and peripheral blood mononuclear cells (PBMCs) of patients with rheumatoid arthritis (RA). METHODS: 133 PBMC samples (61 RA, 72 healthy donors) and 136 serum samples (59 RA, 77 healthy donors) were analysed by quantitative real time polymerase chain reaction for DNA prevalence and viral load of HHV-6, EBV, and CMV. RESULTS: For PBMC samples significant differences were found for EBV in DNA prevalence (56% in RA v 33% in controls, p = 0.009) and viral load (copies/microg DNA 0-592.3 for RA v 0-40.4 for controls, p = 0.001). For serum samples a significant difference was found for HHV-6 DNA prevalence (10% in RA v 0% in controls, p = 0.006) and viral load (copies/microg DNA 0-529.1 for RA v 0 for controls, p = 0.007). CONCLUSIONS: Herpes viruses may have a role in RA, although alternative explanations are possible: (a) defects in cellular immunity in patients with RA may result in a relatively high viral load; (b) patients with RA may be more prone to infection/reactivation. The usefulness of monitoring the DNA viral load in patients with RA is questioned by these data.

Defective early T and T-dependent B cell activation in systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is characterized by autoantibody production of unknown origin. Since T-B cell interaction is a key event to produce antibodies, we investigated this interaction through study of CD69, CD40 ligand (CD40L) and CD23 expression (three very early activation antigens). Peripheral blood mononuclear cells (PBMC) from inactive lupus patients were studied following culture with either medium alone, anti-CD3 monoclonal antibody (mAb), recombinant interleukin-4 (rIL-4) or phorbol myristate acetate (PMA)+/-ionomycin. Analysis of CD23 expression on lupus B cells in basal conditions and after anti-CD3 challenge of PBMC, a reflection of cognate interaction between T and B cells, was clearly defective. Conversely, CD23 expression on lupus B cells following non-cognate T cell signals (rIL-4) was preserved. CD69 and CD40L expression was also impaired in lupus T cells following anti-CD3 challenge. Nonetheless, activation by means of PMA and/or ionomycin was preserved both in T cells (CD69 and CD40L expression) and in B cells (CD23 expression). These results indicate that B cells from inactive lupus patients display a normal early response to direct B-cell stimuli. Conversely, T-dependent B-cell stimuli are clearly defective in SLE patients in remission. These results indicate that T-B cognate interaction related to defective T cell activation located between surface membrane and protein kinase C (PKC)/ionomycin function is an intrinsic characteristic of these patients.