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Dynamic vegetation models have been used to assess the resilience of tropical forests to climate change, but the global application of these modeling experiments often misrepresents carbon dynamics at a regional level, limiting the validity of future projections. Here a dynamic vegetation model (Lund Potsdam Jena General Ecosystem Simulator) was adapted to simulate present-day potential vegetation as a baseline for climate change impact assessments in the evergreen and deciduous forests of Bolivia. Results were compared to biomass measurements (819 plots) and remote sensing data. Using regional parameter values for allometric relations, specific leaf area, wood density, and disturbance interval, a realistic transition from the evergreen Amazon to the deciduous dry forest was simulated. This transition coincided with threshold values for precipitation (1400 mm/yr) and water deficit (i.e., potential evapotranspiration minus precipitation) (-830 mm/yr), beyond which leaf abscission became a competitive advantage. Significant correlations were found between modeled and observed values of seasonal leaf abscission (R2 = 0.6, p<0.001) and vegetation carbon (R2 = 0.31, p<0.01). Modeled Gross Primary Productivity (GPP) and remotely sensed normalized difference vegetation index showed that dry forests were more sensitive to rainfall anomalies than wet forests. GPP was positively correlated to the El Nino-Southern Oscillation index in the Amazon and negatively correlated to consecutive dry days. Decreasing rainfall trends were simulated to reduce GPP in the Amazon. The current model setup provides a baseline for assessing the potential impacts of climate change in the transition zone from wet to dry tropical forests in Bolivia.

Inflorescence architecture of barley (Hordeum vulgare L.) is common among the Triticeae species, which bear one to three single-flowered spikelets at each rachis internode. Triple spikelet meristem is one of the unique features of barley spikes, in which three spikelets (one central and two lateral spikelets) are produced at each rachis internode. Fertility of the lateral spikelets at triple spikelet meristem gives row-type identity to barley spikes. Six-rowed spikes show fertile lateral spikelets and produce increased grain yield per spike, compared with two-rowed spikes with sterile lateral spikelets. Thus, far, two loci governing the row-type phenotype were isolated in barley that include Six-rowed spike1 (Vrs1) and Intermedium-C. In the present study, we isolated Six-rowed spike4 (Vrs4), a barley ortholog of the maize (Zea mays L.) inflorescence architecture gene RAMOSA2 (RA2). Eighteen coding mutations in barley RA2 (HvRA2) were specifically associated with lateral spikelet fertility and loss of spikelet determinacy. Expression analyses through mRNA in situ hybridization and microarray showed that Vrs4 (HvRA2) controls the row-type pathway through Vrs1 (HvHox1), a negative regulator of lateral spikelet fertility in barley. Moreover, Vrs4 may also regulate transcripts of barley SISTER OF RAMOSA3 (HvSRA), a putative trehalose-6-phosphate phosphatase involved in trehalose-6-phosphate homeostasis implicated to control spikelet determinacy. Our expression data illustrated that, although RA2 is conserved among different grass species, its down-stream target genes appear to be modified in barley and possibly other species of tribe Triticeae.

Background. Liver transplantation (LT) is performed for hemangiosarcoma (HAS) despite disappointing results. Methods. Retrospective study of 14 males and 8 females reported to the European Liver Transplant Registry. In view of the difficult differential diagnosis between HAS and hemangioendothelioma (HE), the study was deliberately restricted to the period 1986 to 2004 to allow comparison of clinical and biochemical behavior of HAS and HE liver recipients transplanted during the same time period. Results. Clinical signs, symptoms, and biochemical parameters differed significantly. Pre-LT diagnosis of HAS was made in only 5 of 16 (31%) biopsied patients. HE (7 patients) and hepatocellular cancer (2 patients) were confounding diagnoses leading to LT. Extrahepatic disease was present at time of LT in 4 (19%) patients. Giant invalidating tumor (5 HAS, 1 with Budd-Chiari syndrome [BCS], and 10 supposed epithelioid hemangioendothelioma, 1 with BCS), acute BCS of unknown origin (2 patients), chronic liver failure (4 patients), and solitary hepatocellular cancer (1 patient) were the main indications for LT. Overall survival was 7.2±2.6 months; no patient survived after 23 months. Recurrence was diagnosed after 5.0±2.6 months. Seventeen (77.2%) patients died of tumor recurrence, and the remaining 5 patients died of early infections. Conclusions. HAS is an absolute contraindication to LT due to the poor outcome. When dealing with the difficult differential diagnosis between HAS and HE, futile LT can be avoided by taking into consideration their distinct clinical and biochemical behaviors as well as a 6-month wait-list observation period. This time period enables the evaluation of HAS disease progression without compromising prognosis of HE patients, thereby allowing to avoid organ wastage. © 2013 Lippincott Williams & Wilkins.

Bolivia is facing numerous climate-related threats, ranging from water scarcity due to rapidly retreating glaciers in the Andes to a partial loss of the Amazon forest in the lowlands. To assess what changes in climate may be expected in the future, 35 global circulation models (GCMs) from the third and fifth phases of the Coupled Model Intercomparison Project (CMIP3/5) were analyzed for the Bolivian case. GCMs were validated against observed surface air temperature, precipitation, and incoming shortwave (SW) radiation for the period 1961-90. Weighted ensembles were developed, and climate change projections for five emission scenarios were assessed for 2070-99. GCMs revealed an overall cold, wet, and positive-SW-radiation bias and showed no substantial improvement from the CMIP3 to the CMIP5 ensemble for the Bolivian case. Models projected an increase in temperature (2.5-5.9 degrees Celsius) and SW radiation (1%-5%), with seasonal and regional differences. In the lowlands, changes in annual rainfall remained uncertain for CMIP3 whereas CMIP5 GCMs were more inclined to project decreases (-9%). This pattern also applied to most of the Amazon basin, suggesting a higher risk of partial biomass loss for the CMIP5 ensemble. Both ensembles agreed on less rainfall (-9%) during drier months (June-August and September-November), with significant changes in interannual rainfall variability, but disagreed on changes during wetter months (January-March). In the Andes, CMIP3 GCMs tended toward less rainfall (-9%) whereas CMIP5 tended toward more (+20%) rainfall during parts of the wet season. The findings presented here may provide inputs for studies of climate change impact that assess how resilient human and natural systems are under different climate change scenarios.

Climate-related disasters in Bolivia are frequent, severe, and manifold and affect large parts of the population, economy, and ecosystems. Potentially amplified through climate change, natural hazards are of growing concern. To better understand these events, homogenized daily observations of temperature (29 stations) and precipitation (68 stations) from 1960 to 2009 were analyzed in this study. The impact of the positive (+) and negative (-) phases of the three climate modes (i) Pacific decadal oscillation (PDO), (ii) El Nino-Southern Oscillation (ENSO) with El Nino (EN) and La Nina (LN) events, and (iii) Antarctic Oscillation (AAO) were assessed. Temperatures were found to be higher during PDO(+), EN, and AAO(+) in the Andes. Total amounts of rainfall, as well as the number of extreme events, were higher during PDO(+), EN, and LN in the lowlands. During austral summer [December-February (DJF)], EN led to drier conditions in the Andes with more variable precipitation. Temperatures increased at a rate of 0.1 degrees C per decade, with stronger increases in the Andes and in the dry season. Rainfall totals increased from 1965 to 1984 [12% in DJF and 18% in June-August (JJA)] and decreased afterward (-4% in DJF and -10% in JJA), following roughly the pattern of PDO. Trends of climate extremes generally corresponded to trends of climate means. Findings suggest that Bolivia's climate will be warmer and drier than average in the near-term future. Having entered PDO(.) in 2007, droughts and LN-related floods can be expected in the lowlands, while increasing temperatures suggest higher risks of drought in the Andes.

Aims Late acquired incomplete stent apposition (ISA) is more common after drug-eluting stent (DES) than bare metal stent (BMS) implantation and has been associated with vascular hypersensitivity and stent thrombosis (ST). We investigated the impact of incidentally discovered ISA as assessed by intravascular ultrasound (IVUS) 8 months after DES implantation on the long-term clinical outcome. Methods and results A total of 194 patients with 221 lesions were prospectively followed through 5 years. At 8 months, IVUS showed evidence of ISA among 37 patients with 39 lesions (18%) (mean ISAmax 4.7 ± 5.0 mm2), whereas no ISA was observed among 157 patients with 182 lesions. Incomplete stent apposition was more prevalent among segments treated with sirolimus-eluting (n = 103) than paclitaxel-eluting stents (n = 118) (27 vs. 9%, P = 0.001). Between IVUS investigation at the 8-month and 5-year follow-up, major adverse cardiac events occurred more frequently in patients with (18.9%, n = 7) than without ISA (7.0%, n = 11) (HR = 2.71, 95% CI: 1.05-6.96, P = 0.031). While there were no differences with respect to death, the rate of myocardial infarction was higher among patients with (13.5%, n = 5) than without ISA (1.9%, n = 3) (HR = 7.53, 95% CI: 1.79-31.6, P = 0.001). Very late ST was more common among patients with than without ISA [Academic Research Consortium-definite ST:13.5% (n = 5) vs. 0.6% (n = 1) HR = 23.2, 95% CI: 2.65-203, P < 0.001]. Conclusion In the present study, the presence of ISA as assessed by IVUS 8 months after DES implantation was associated with a higher rate of myocardial infarction and very late stent thrombosis during long-term follow-up. The prognostic impact of ISA on long-term clinical outcomes requires further investigation

BACKGROUND: Pancreatic cancer has an extremely poor prognosis and prolonged survival is achieved only by resection with macroscopic tumor clearance. There is a strong rationale for a neoadjuvant approach, since a relevant percentage of pancreatic cancer patients present with non-metastatic but locally advanced disease and microscopic incomplete resections are common. The objective of the present analysis was to systematically review studies concerning the effects of neoadjuvant therapy on tumor response, toxicity, resection, and survival percentages in pancreatic cancer. METHODS AND FINDINGS: Trials were identified by searching MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials from 1966 to December 2009 as well as through reference lists of articles and proceedings of major meetings. Retrospective and prospective studies analyzing neoadjuvant radiochemotherapy, radiotherapy, or chemotherapy of pancreatic cancer patients, followed by re-staging, and surgical exploration/resection were included. Two reviewers independently extracted data and assessed study quality. Pooled relative risks and 95% confidence intervals were calculated using random-effects models. Primary outcome measures were proportions of tumor response categories and percentages of exploration and resection. A total of 111 studies (n = 4,394) including 56 phase I-II trials were analyzed. A median of 31 (interquartile range [IQR] 19-46) patients per study were included. Studies were subdivided into surveys considering initially resectable tumors (group 1) and initially non-resectable (borderline resectable/unresectable) tumors (group 2). Neoadjuvant chemotherapy was given in 96.4% of the studies with the main agents gemcitabine, 5-FU (and oral analogues), mitomycin C, and platinum compounds. Neoadjuvant radiotherapy was applied in 93.7% of the studies with doses ranging from 24 to 63 Gy. Averaged complete/partial response probabilities were 3.6% (95% CI 2%-5.5%)/30.6% (95% CI 20.7%

Aims Percutaneous coronary intervention (PCI) in diabetic patients is associated with an increased risk of restenosis and major adverse cardiac events (MACE). We assessed the impact of diabetes on long-term outcome after PCI with sirolimus-eluting (SES) and paclitaxel-eluting (PES) stents. Methods and results In the SIRTAX trial, 1012 patients were randomized to treatment with SES (n = 503) or PES (n = 509). A stratified analysis of outcomes was performed according to the presence or absence of diabetes. Baseline characteristics were well balanced between SES and PES in patients with (N = 201) and without diabetes (N = 811). Clinical outcome was worse in diabetic compared with non-diabetic patients regarding death (9.0% vs. 4.1%, P = 0.004) and MACE (defined as cardiac death, myocardial infarction, or TLR; 19.9% vs. 12.7%, P = 0.007) at 2 years. Among diabetic patients, SES reduced MACE by 47% (14.8% vs. 25.8%, HR = 0.52, P = 0.05) and TLR by 61% (7.4% vs. 17.2%, HR = 0.39, P = 0.03) compared with PES at 2 years. Conclusion Diabetic patients have worse prognosis than non-diabetic patients undergoing PCI with DES. Among the diabetic patient population of this trial, SES reduce repeat revascularization procedures and MACE more effectively than PES and to a similar degree as in non-diabetic patients

BACKGROUND: Large-scale mutagenesis screens in the zebrafish employing the mutagen ENU have isolated several hundred mutant loci that represent putative developmental control genes. In order to realize the potential of such screens, systematic genetic mapping of the mutations is necessary. Here we report on a large-scale effort to map the mutations generated in mutagenesis screening at the Max Planck Institute for Developmental Biology by genome scanning with microsatellite markers. RESULTS: We have selected a set of microsatellite markers and developed methods and scoring criteria suitable for efficient, high-throughput genome scanning. We have used these methods to successfully obtain a rough map position for 319 mutant loci from the Tübingen I mutagenesis screen and subsequent screening of the mutant collection. For 277 of these the corresponding gene is not yet identified. Mapping was successful for 80 % of the tested loci. By comparing 21 mutation and gene positions of cloned mutations we have validated the correctness of our linkage group assignments and estimated the standard error of our map positions to be approximately 6 cM. CONCLUSION: By obtaining rough map positions for over 300 zebrafish loci with developmental phenotypes, we have generated a dataset that will be useful not only for cloning of the affected genes, but also to suggest allelism of mutations with similar phenotypes that will be identified in future screens. Furthermore this work validates the usefulness of our methodology for rapid, systematic and inexpensive microsatellite mapping of zebrafish mutations.