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1.
Echocardiography ; 38(1): 144-146, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33205464

RESUMO

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.


Assuntos
Endocardite Bacteriana , Endocardite , Próteses Valvulares Cardíacas , Infecções Relacionadas à Prótese , Endocardite/diagnóstico por imagem , Endocardite Bacteriana/diagnóstico por imagem , Próteses Valvulares Cardíacas/efeitos adversos , Humanos , Infecções Relacionadas à Prótese/diagnóstico por imagem , Transiluminação
2.
Ecol Lett ; 17(5): 527-36, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24589190

RESUMO

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.


Assuntos
Biodiversidade , Modelos Biológicos , Árvores/fisiologia , América do Sul , Clima Tropical
3.
Glob Ecol Biogeogr ; 23(8): 935-946, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26430387

RESUMO

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.

4.
J Org Chem ; 79(21): 10689-95, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25275892

RESUMO

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.


Assuntos
Produtos Biológicos/química , Diterpenos/química , Ftalimidas/química , Sesquiterpenos/síntese química , Ciclização , Estrutura Molecular , Sesquiterpenos/química , Compostos de Estanho/química
5.
J Org Chem ; 79(10): 4405-13, 2014 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-24735394

RESUMO

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.


Assuntos
Abietanos/química , Diterpenos/química , Diterpenos/síntese química , Espironolactona/análogos & derivados , Espironolactona/síntese química , Ciclização , Estrutura Molecular , Espironolactona/química , Estereoisomerismo
6.
Org Biomol Chem ; 12(4): 667-72, 2014 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-24302444

RESUMO

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.


Assuntos
Diterpenos/síntese química , Lactonas/síntese química , Compostos de Espiro/síntese química , Diterpenos/química , Lactonas/química , Conformação Molecular , Compostos de Espiro/química , Estereoisomerismo
7.
J Org Chem ; 78(18): 9196-204, 2013 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-23984842

RESUMO

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.


Assuntos
Indicadores e Reagentes/química , Fenóis/química , Fosfinas/química , Sesquiterpenos/síntese química , Compostos de Espiro/síntese química , Succinimidas/química , Conformação Molecular , Sesquiterpenos/química , Compostos de Espiro/química
8.
Org Biomol Chem ; 11(36): 6176-85, 2013 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-23928887

RESUMO

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.


Assuntos
Antineoplásicos/síntese química , Diterpenos/síntese química , Antineoplásicos/química , Ascomicetos/química , Diterpenos/química , Conformação Molecular , Estereoisomerismo
9.
Plants (Basel) ; 12(10)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37653883

RESUMO

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.

10.
Front Immunol ; 14: 1113858, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37033927

RESUMO

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.


Assuntos
Leucemia Linfocítica Crônica de Células B , Receptor de Morte Celular Programada 1 , Animais , Humanos , Camundongos , Linhagem Celular , Células Matadoras Naturais/metabolismo , Receptor de Morte Celular Programada 1/genética , Receptores Imunológicos/metabolismo
11.
J Org Chem ; 77(1): 573-84, 2012 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-22118292

RESUMO

A new strategy for synthesizing taiwaniaquinoids, a group of terpenoids with an unusual rearranged 5(6→7) or 6-nor-5(6→7)abeo-abietane skeleton, which exhibit promising biological activities, is reported. The procedure, based on the cleavage of the C7-C8 double bond of abietane diterpenes, is the only one yet reported for synthesizing C(20) taiwaniaquinoids bearing a carbon function on the cyclopentane B ring; it is also applicable to the synthesis of the wide variety of existing taiwaniaquinoids. Utilizing this, (-)-taiwaniaquinone A, F, G, and H, (-)-taiwaniaquinol B, and (-)-dichroanone have been synthesized from (+)-abietic acid. The versatility of this strategy allows us to propose the abietane C7-C8 cleavage as a possible biosynthetic pathway to this type of rearranged diterpenes; this proposal seems to be supported by phytochemical evidence.


Assuntos
Abietanos/química , Diterpenos/química , Diterpenos/síntese química , Terpenos/química , Terpenos/síntese química , Estrutura Molecular , Estereoisomerismo
12.
Eur Heart J Cardiovasc Imaging ; 24(1): 108-118, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-35175338

RESUMO

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.


Assuntos
Insuficiência da Valva Mitral , Disfunção Ventricular Esquerda , Humanos , Pessoa de Meia-Idade , Idoso , Prognóstico , Teste de Esforço/métodos , Ecocardiografia , Função Ventricular Esquerda , Volume Sistólico , Diástole , Dispneia
13.
PLoS One ; 16(9): e0257613, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34543345

RESUMO

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.


Assuntos
COVID-19/diagnóstico , COVID-19/mortalidade , Progressão da Doença , Registros Hospitalares , Hospitais , Atenção Primária à Saúde , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/complicações , Calibragem , Criança , Pré-Escolar , Comorbidade , Intervalos de Confiança , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Probabilidade , Modelos de Riscos Proporcionais , Reprodutibilidade dos Testes , Espanha/epidemiologia , Adulto Jovem , Tratamento Farmacológico da COVID-19
14.
Chem Commun (Camb) ; (5): 592-4, 2009 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-19283301

RESUMO

The first route towards taiwaniaquinoid terpenes bearing an A/B trans-configuration has been developed through a sequence which includes a thermal 6pi electrocyclization.


Assuntos
Diterpenos/síntese química , Ciclização , Diterpenos/química , Elétrons , Estereoisomerismo , Temperatura
15.
J Org Chem ; 74(9): 3384-8, 2009 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19348490

RESUMO

A very expedient and efficient new route toward taiwaniaquinoids, bearing the 4a-methyltetrahydrofluorene skeleton, is reported. Key steps are the intramolecular Friedel-Crafts alkylation of an aryldiene and the degradative oxidation of a methylenedioxy group; the latter process could also be utilized for building the 2-hydroxy-1,4-benzoquinone unit, which is frequently found in natural products. Utilizing this new methodology, (+/-)-dichroanone (7) (three steps, 77% overall yield) and (+/-)-taiwaniaquinone H (6) (four steps, 70% overall yield) have been synthesized from commercial alpha- (11a) or beta-cyclocitral (11b).


Assuntos
Diterpenos/síntese química , Fluorenos/química , Alquilação , Diterpenos/química , Oxirredução , Estereoisomerismo
16.
Org Biomol Chem ; 7(24): 5146-55, 2009 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-20024110

RESUMO

A new methodology for the enantiospecific synthesis of taiwaniaquinoids, based on a thermal 6pi electrocyclization, is reported. Under this procedure, 4a-methylhexahydrofluorene terpenoids bearing an A/B trans-configuration has been prepared for the first time. This methodology also makes it feasible to synthesize taiwaniaquinoids with an A/B cis-configuration and 4a-methyltetrahydrofluorene terpenoids. Accordingly, the first synthesis of (-)-taiwaniaquinone G, (-)-taiwaniaquinone H and (-)-dichroanone has been achieved.


Assuntos
Diterpenos/síntese química , Ciclização , Métodos , Estereoisomerismo , Terpenos/síntese química
19.
ASAIO J ; 62(1): 74-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26418206

RESUMO

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.


Assuntos
Injúria Renal Aguda/terapia , Estado Terminal/terapia , Análise do Modo e do Efeito de Falhas na Assistência à Saúde , Terapia de Substituição Renal/métodos , Gestão da Segurança , Idoso , Estudos de Coortes , Cuidados Críticos/métodos , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Estudos Retrospectivos
20.
Science ; 353(6306): 1383-1387, 2016 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-27708031

RESUMO

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.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Florestas , Árvores , Região do Caribe , Tomada de Decisões , Pradaria , América Latina , Estações do Ano , Clima Tropical , Madeira
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