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4.
Plants (Basel) ; 12(10)2023 May 12.
Article in English | MEDLINE | ID: mdl-37653883

ABSTRACT

Rising temperatures and changes in precipitation patterns under climate change scenarios are accelerating the depletion of soil moisture and increasing the risk of drought, disrupting the conditions that many plant species need to survive. This study aims to establish the bioclimatic characterisation, both qualitative and quantitative, of ten native Californian Pinales for the period 1980-2019, and to determine their habitat suitability by 2050. To achieve this, an exhaustive search of the Gbif database for records of ten conifer taxa was carried out. To conduct the bioclimatic characterisation of the studied taxa, we worked with the monthly values of average temperature and precipitation for the period 1980-2019 from 177 meteorological stations. Linear regressions was performed in order to compile the future evolution of California's climate. Suitable areas and optimal areas were defined at the present time (1980-2019) and its future projection (2050). We applied Boolean logic and, in this investigation, the Conditional Logic Operator (CON) was used to determine the possible species presence (one) or absence (zero) for each of the 15 variables analysed. In general, most of the conifers studied here will experience a reduction in their habitat range in California by the year 2050 due to climate change, as well as the displacement of species towards optimal areas. Furthermore, the results have highlighted the applicability of bioclimatology to future conditions under climate change. This will aid conservation managers in implementing strategic measures to ameliorate the detrimental impacts of climate change, thereby ensuring the ecological integrity and sustainability of the affected conifer species.

5.
Front Immunol ; 14: 1113858, 2023.
Article in English | MEDLINE | ID: mdl-37033927

ABSTRACT

Introduction: A high frequency of mutations affecting the gene encoding Herpes Virus Entry Mediator (HVEM, TNFRSF14) is a common clinical finding in a wide variety of human tumors, including those of hematological origin. Methods: We have addressed how HVEM expression on A20 leukemia cells influences tumor survival and its involvement in the modulation of the anti-tumor immune responses in a parental into F1 mouse tumor model of hybrid resistance by knocking-out HVEM expression. HVEM WT or HVEM KO leukemia cells were then injected intravenously into semiallogeneic F1 recipients and the extent of tumor dissemination was evaluated. Results: The loss of HVEM expression on A20 leukemia cells led to a significant increase of lymphoid and myeloid tumor cell infiltration curbing tumor progression. NK cells and to a lesser extent NKT cells and monocytes were the predominant innate populations contributing to the global increase of immune infiltrates in HVEM KO tumors compared to that present in HVEM KO tumors. In the overall increase of the adaptive T cell immune infiltrates, the stem cell-like PD-1- T cells progenitors and the effector T cell populations derived from them were more prominently present than terminally differentiated PD-1+ T cells. Conclusions: These results suggest that the PD-1- T cell subpopulation is likely to be a more relevant contributor to tumor rejection than the PD-1+ T cell subpopulation. These findings highlight the role of co-inhibitory signals delivered by HVEM upon engagement of BTLA on T cells and NK cells, placing HVEM/BTLA interaction in the spotlight as a novel immune checkpoint for the reinforcement of the anti-tumor responses in malignancies of hematopoietic origin.


Subject(s)
Leukemia, Lymphocytic, Chronic, B-Cell , Programmed Cell Death 1 Receptor , Animals , Humans , Mice , Cell Line , Killer Cells, Natural/metabolism , Programmed Cell Death 1 Receptor/genetics , Receptors, Immunologic/metabolism
6.
Eur Heart J Cardiovasc Imaging ; 24(1): 108-118, 2022 12 19.
Article in English | MEDLINE | ID: mdl-35175338

ABSTRACT

AIMS: Exercise echocardiography (ExE) may evaluate left ventricular (LV) systolic and diastolic function. We aimed to assess the value of diastolic parameters at exercise [early LV inflow velocity to early tissue Doppler annulus velocity (E/e')] in patients with normal or abnormal resting diastolic function (DF) referred for a clinically indicated ExE. METHODS AND RESULTS: LV systolic and DF according to ASE/EACVI guidelines and mitral regurgitation (MR) were evaluated at rest in 772 patients (age 67 ± 12 years) with preserved LV ejection fraction (LVEF ≥ 50%). We assessed regional/global LV systolic function at peak exercise, while MR and E/e' where evaluated in the immediate post-exercise period. Abnormal ExE was defined as ischaemia or fixed wall motion abnormalities, and raised E/e' values as >15 at rest and at exercise (e' at the septal level). Patients were grouped as complaining or not of dyspnoea. Events were overall mortality, myocardial infarction, admission for unstable angina or cardiac failure, and coronary revascularization. DF was abnormal at rest in 221 patients (29%) and indeterminate in 77 (10%), with similar percentages in patients with and without dyspnoea. Exercise E/e' >15 was found in 37% of patients with abnormal DF, 21% with indeterminate DF, and 6% with normal DF (P < 0.001). Patients with abnormal ExE had more often abnormal resting DF (39% vs. 25%, P = 0.001) and exercise E/e' >15 (25% vs. 13%, P < 0.001) than those with normal ExE. During a median follow-up of 1.68 years, there were 132 events. Independent predictors included peak exercise LVEF [hazard ratio (HR) = 0.93, 95% confidence interval (CI) = 0.91-0.94, P < 0.001], and exercise E/e' (HR= 1.04, 95% CI = 1.01-1.07, P = 0.01). Neither resting E/e' values nor resting abnormal DF by ASE/EACVI guidelines, were independent predictors. Annualized event-rates were 43.2% in patients with (+) ExE plus (+) exercise E/e', 23.8% in those with (+) ExE and (-) exercise E/e', 7.9% in (-) ExE and (+) exercise E/e', and 3.6% with both variables normal. CONCLUSIONS: The results of diastolic dysfunction at rest and at exercise were similar between patients with or without dyspnoea referred for ExE, but they were associated with abnormal ExE. Exercise E/e' reclassified 21% of patients with indeterminate DF and further predicted outcome on top of ExE results.


Subject(s)
Mitral Valve Insufficiency , Ventricular Dysfunction, Left , Humans , Middle Aged , Aged , Prognosis , Exercise Test/methods , Echocardiography , Ventricular Function, Left , Stroke Volume , Diastole , Dyspnea
7.
PLoS One ; 16(9): e0257613, 2021.
Article in English | MEDLINE | ID: mdl-34543345

ABSTRACT

This paper analyses COVID-19 patients' dynamics during the first wave in the region of Castilla y León (Spain) with around 2.4 million inhabitants using multi-state competing risk survival models. From the date registered as the start of the clinical process, it is assumed that a patient can progress through three intermediate states until reaching an absorbing state of recovery or death. Demographic characteristics, epidemiological factors such as the time of infection and previous vaccinations, clinical history, complications during the course of the disease and drug therapy for hospitalised patients are considered as candidate predictors. Regarding risk factors associated with mortality and severity, consistent results with many other studies have been found, such as older age, being male, and chronic diseases. Specifically, the hospitalisation (death) rate for those over 69 is 27.2% (19.8%) versus 5.3% (0.7%) for those under 70, and for males is 14.5%(7%) versus 8.3%(4.6%)for females. Among patients with chronic diseases the highest rates of hospitalisation are 26.1% for diabetes and 26.3% for kidney disease, while the highest death rate is 21.9% for cerebrovascular disease. Moreover, specific predictors for different transitions are given, and estimates of the probability of recovery and death for each patient are provided by the model. Some interesting results obtained are that for patients infected at the end of the period the hazard of transition from hospitalisation to ICU is significatively lower (p < 0.001) and the hazard of transition from hospitalisation to recovery is higher (p < 0.001). For patients previously vaccinated against pneumococcus the hazard of transition to recovery is higher (p < 0.001). Finally, internal validation and calibration of the model are also performed.


Subject(s)
COVID-19/diagnosis , COVID-19/mortality , Disease Progression , Hospital Records , Hospitals , Primary Health Care , Adolescent , Adult , Aged , Aged, 80 and over , COVID-19/complications , Calibration , Child , Child, Preschool , Comorbidity , Confidence Intervals , Female , Humans , Infant , Infant, Newborn , Male , Middle Aged , Probability , Proportional Hazards Models , Reproducibility of Results , Spain/epidemiology , Young Adult , COVID-19 Drug Treatment
8.
Echocardiography ; 38(1): 144-146, 2021 01.
Article in English | MEDLINE | ID: mdl-33205464

ABSTRACT

Prosthetic valve endocarditis is a rare but serious complication of cardiac valve replacement, and echocardiography plays a fundamental role in its diagnosis and management. However, there is not much information about the use of the 3D transillumination rendering in this context. In this report, we present an unusual case of prosthetic valve endocarditis that exemplifies the utility of this new tool.


Subject(s)
Endocarditis, Bacterial , Endocarditis , Heart Valve Prosthesis , Prosthesis-Related Infections , Endocarditis/diagnostic imaging , Endocarditis, Bacterial/diagnostic imaging , Heart Valve Prosthesis/adverse effects , Humans , Prosthesis-Related Infections/diagnostic imaging , Transillumination
9.
Science ; 353(6306): 1383-1387, 2016 09 23.
Article in English | MEDLINE | ID: mdl-27708031

ABSTRACT

Seasonally dry tropical forests are distributed across Latin America and the Caribbean and are highly threatened, with less than 10% of their original extent remaining in many countries. Using 835 inventories covering 4660 species of woody plants, we show marked floristic turnover among inventories and regions, which may be higher than in other neotropical biomes, such as savanna. Such high floristic turnover indicates that numerous conservation areas across many countries will be needed to protect the full diversity of tropical dry forests. Our results provide a scientific framework within which national decision-makers can contextualize the floristic significance of their dry forest at a regional and continental scale.


Subject(s)
Biodiversity , Conservation of Natural Resources/methods , Forests , Trees , Caribbean Region , Decision Making , Grassland , Latin America , Seasons , Tropical Climate , Wood
10.
ASAIO J ; 62(1): 74-9, 2016.
Article in English | MEDLINE | ID: mdl-26418206

ABSTRACT

The failure mode and effect analysis (FMEA) may improve the safety of the continuous renal replacement therapies (CRRT) in the intensive care unit. We use this tool in three phases: 1) Retrospective observational study. 2) A process FMEA, with implementation of the improvement measures identified. 3) Cohort study after FMEA. We included 54 patients in the pre-FMEA group and 72 patients in the post-FMEA group. Comparing the risks frequencies per patient in both groups, we got less cases of under 24 hours of filter survival time in the post-FMEA group (31 patients 57.4% vs. 21 patients 29.6%; p < 0.05); less patients suffered circuit coagulation with inability to return the blood to the patient (25 patients [46.3%] vs. 16 patients [22.2%]; p < 0.05); 54 patients (100%) versus 5 (6.94%) did not get phosphorus levels monitoring (p < 0.05); in 14 patients (25.9%) versus 0 (0%), the CRRT prescription did not appear on medical orders. As a measure of improvement, we adopt a dynamic dosage management. After the process FMEA, there were several improvements in the management of intensive care unit patients receiving CRRT, and we consider it a useful tool for improving the safety of critically ill patients.


Subject(s)
Acute Kidney Injury/therapy , Critical Illness/therapy , Healthcare Failure Mode and Effect Analysis , Renal Replacement Therapy/methods , Safety Management , Aged , Cohort Studies , Critical Care/methods , Female , Humans , Intensive Care Units , Male , Middle Aged , Outcome and Process Assessment, Health Care , Retrospective Studies
11.
PLoS One ; 10(5): e0126594, 2015.
Article in English | MEDLINE | ID: mdl-25973977

ABSTRACT

General patterns of forest dynamics and productivity in the Andes Mountains are poorly characterized. Here we present the first large-scale study of Andean forest dynamics using a set of 63 permanent forest plots assembled over the past two decades. In the North-Central Andes tree turnover (mortality and recruitment) and tree growth declined with increasing elevation and decreasing temperature. In addition, basal area increased in Lower Montane Moist Forests but did not change in Higher Montane Humid Forests. However, at higher elevations the lack of net basal area change and excess of mortality over recruitment suggests negative environmental impacts. In North-Western Argentina, forest dynamics appear to be influenced by land use history in addition to environmental variation. Taken together, our results indicate that combinations of abiotic and biotic factors that vary across elevation gradients are important determinants of tree turnover and productivity in the Andes. More extensive and longer-term monitoring and analyses of forest dynamics in permanent plots will be necessary to understand how demographic processes and woody biomass are responding to changing environmental conditions along elevation gradients through this century.


Subject(s)
Forests , Biodiversity , Linear Models , Principal Component Analysis , Trees/growth & development
12.
J Org Chem ; 79(21): 10689-95, 2014 Nov 07.
Article in English | MEDLINE | ID: mdl-25275892

ABSTRACT

Synthesis of the putative structure of the marine natural 15-oxopuupehenoic acid has been achieved starting from commercial (-)-sclareol. Key steps of the synthetic sequence are the Robinson annulation of a ß-ketoester and methyl vinyl ketone and an unprecedented cyclization of the resulting α,ß-enone, which is mediated by tin(IV) chloride in the presence of N-phenylselenophthalimide. The physical properties of the synthetic compound are somewhat different from those reported for the natural product.


Subject(s)
Biological Products/chemistry , Diterpenes/chemistry , Phthalimides/chemistry , Sesquiterpenes/chemical synthesis , Cyclization , Molecular Structure , Sesquiterpenes/chemistry , Tin Compounds/chemistry
13.
Chem Commun (Camb) ; 50(86): 13100-2, 2014 Nov 07.
Article in English | MEDLINE | ID: mdl-25225658

ABSTRACT

A short synthetic sequence for the preparation of merosesquiterpenes with a benzoxanthene skeleton starting from commercial (-)-sclareol is reported. The D ring of the target compound is obtained through a Diels-Alder cycloaddition, involving a dienoldiether derived from a tricyclic α,ß-enone synthesized in two steps from the starting diterpene. Utilizing this procedure, the preparation of (+)-hongoquercin A and the first synthesis of (+)-cyclospongiaquinone-1 were achieved.


Subject(s)
Sesquiterpenes/chemistry , Xanthenes/chemistry , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cycloaddition Reaction , Diterpenes/chemistry , Sesquiterpenes/chemical synthesis , Stereoisomerism
14.
J Org Chem ; 79(10): 4405-13, 2014 May 16.
Article in English | MEDLINE | ID: mdl-24735394

ABSTRACT

The first synthesis of spirolactone (+)-vitedoin B (14 steps, 8.0% global yield) and spiro enol ether (+)-negundoin A (19 steps, 3.7% global yield), via a nor-labdane acetoxy ester, has been achieved starting from commercial (+)-abietic acid.


Subject(s)
Abietanes/chemistry , Diterpenes/chemistry , Diterpenes/chemical synthesis , Spironolactone/analogs & derivatives , Spironolactone/chemical synthesis , Cyclization , Molecular Structure , Spironolactone/chemistry , Stereoisomerism
15.
Ecol Lett ; 17(5): 527-36, 2014 May.
Article in English | MEDLINE | ID: mdl-24589190

ABSTRACT

The Amazon rain forest sustains the world's highest tree diversity, but it remains unclear why some clades of trees are hyperdiverse, whereas others are not. Using dated phylogenies, estimates of current species richness and trait and demographic data from a large network of forest plots, we show that fast demographic traits--short turnover times--are associated with high diversification rates across 51 clades of canopy trees. This relationship is robust to assuming that diversification rates are either constant or decline over time, and occurs in a wide range of Neotropical tree lineages. This finding reveals the crucial role of intrinsic, ecological variation among clades for understanding the origin of the remarkable diversity of Amazonian trees and forests.


Subject(s)
Biodiversity , Models, Biological , Trees/physiology , South America , Tropical Climate
16.
Glob Ecol Biogeogr ; 23(8): 935-946, 2014 Aug.
Article in English | MEDLINE | ID: mdl-26430387

ABSTRACT

AIM: The accurate mapping of forest carbon stocks is essential for understanding the global carbon cycle, for assessing emissions from deforestation, and for rational land-use planning. Remote sensing (RS) is currently the key tool for this purpose, but RS does not estimate vegetation biomass directly, and thus may miss significant spatial variations in forest structure. We test the stated accuracy of pantropical carbon maps using a large independent field dataset. LOCATION: Tropical forests of the Amazon basin. The permanent archive of the field plot data can be accessed at: http://dx.doi.org/10.5521/FORESTPLOTS.NET/2014_1. METHODS: Two recent pantropical RS maps of vegetation carbon are compared to a unique ground-plot dataset, involving tree measurements in 413 large inventory plots located in nine countries. The RS maps were compared directly to field plots, and kriging of the field data was used to allow area-based comparisons. RESULTS: The two RS carbon maps fail to capture the main gradient in Amazon forest carbon detected using 413 ground plots, from the densely wooded tall forests of the north-east, to the light-wooded, shorter forests of the south-west. The differences between plots and RS maps far exceed the uncertainties given in these studies, with whole regions over- or under-estimated by > 25%, whereas regional uncertainties for the maps were reported to be < 5%. MAIN CONCLUSIONS: Pantropical biomass maps are widely used by governments and by projects aiming to reduce deforestation using carbon offsets, but may have significant regional biases. Carbon-mapping techniques must be revised to account for the known ecological variation in tree wood density and allometry to create maps suitable for carbon accounting. The use of single relationships between tree canopy height and above-ground biomass inevitably yields large, spatially correlated errors. This presents a significant challenge to both the forest conservation and remote sensing communities, because neither wood density nor species assemblages can be reliably mapped from space.

17.
Org Biomol Chem ; 12(4): 667-72, 2014 Jan 28.
Article in English | MEDLINE | ID: mdl-24302444

ABSTRACT

A very efficient method for synthesizing spirolactones is reported. Treatment of δ,ε-unsaturated carboxylic acids with iodine and triphenylphosphine under mild conditions leads to the corresponding spiro γ-lactones in high yield and with complete stereoselectivity. Utilizing this, the first synthesis of the terpene spirolactones (-)-isoambreinolide, (+)-vitexifolin D and (+)-vitedoin B has been achieved.


Subject(s)
Diterpenes/chemical synthesis , Lactones/chemical synthesis , Spiro Compounds/chemical synthesis , Diterpenes/chemistry , Lactones/chemistry , Molecular Conformation , Spiro Compounds/chemistry , Stereoisomerism
18.
Chem Commun (Camb) ; 49(87): 10257-9, 2013 Nov 11.
Article in English | MEDLINE | ID: mdl-24060986

ABSTRACT

An efficient and stereoselective spiroannulation of unsaturated enols is reported. Unsaturated ß-dicarbonyl compounds undergo cyclization by reaction with catalytic I2-PPh3, affording the corresponding spiro enol ether derivatives, with complete regio- and stereoselectivity, under mild conditions. Utilizing this new methodology, the first total synthesis of the anti-inflammatory diterpene negundoin A and a naturally occurring trypanocidal aldehyde is reported.


Subject(s)
Diterpenes/chemical synthesis , Iodine/chemistry , Ketones/chemistry , Organophosphorus Compounds/chemistry , Spiro Compounds/chemical synthesis , Catalysis , Cyclization , Diterpenes/chemistry , Molecular Structure , Spiro Compounds/chemistry
19.
Org Biomol Chem ; 11(36): 6176-85, 2013 Sep 28.
Article in English | MEDLINE | ID: mdl-23928887

ABSTRACT

The first synthesis of dasyscyphin B, an antitumoral metabolite obtained from the ascomycete Dasyscyphus niveus, has been achieved starting from commercial abietic acid. The key steps of the synthetic sequence are the diastereoselective α-methylation of a ketoaldehyde, followed by an intramolecular aldol condensation and the further Diels-Alder cycloaddition of a dienol ester. The procedure reported will allow the synthesis of related metabolites functionalized in the A ring.


Subject(s)
Antineoplastic Agents/chemical synthesis , Diterpenes/chemical synthesis , Antineoplastic Agents/chemistry , Ascomycota/chemistry , Diterpenes/chemistry , Molecular Conformation , Stereoisomerism
20.
J Org Chem ; 78(18): 9196-204, 2013 Sep 20.
Article in English | MEDLINE | ID: mdl-23984842

ABSTRACT

Treatment of o-allyl phenols with catalytic NIS-PPh3 affords the corresponding spirodihydrobenzofuran derivatives in high yield with high regio- and total stereoselectivity under mild conditions. These results were utilized to achieve the first total synthesis of the protein kinase C inhibitor corallidictyal D starting from α-ionone.


Subject(s)
Indicators and Reagents/chemistry , Phenols/chemistry , Phosphines/chemistry , Sesquiterpenes/chemical synthesis , Spiro Compounds/chemical synthesis , Succinimides/chemistry , Molecular Conformation , Sesquiterpenes/chemistry , Spiro Compounds/chemistry
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