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1.
Talanta ; 271: 125639, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38219327

RESUMO

Moonmilk-type deposits exemplify carbonated Martian analogues existing in the subsurface of Earth, an endokarstic speleothem with a possible biochemical origin composed principally by carbonates, mainly huntite and dolomite. In this work, samples of moonmilk located in Nerja Cave (southern Spain) have been studied by LIBS with the aim of identifying carbon of biogenic origin by establishing a relationship between a molecular emission indicator, CN signal, and the organic carbon content. The characterization of this kind of carbonate deposit with a multiple mineralogical composition has been completed using scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and X-ray diffraction techniques for qualitative and semi-quantitative analysis. The information attained from LIBS regarding energy thresholds and time-resolved kinetics of CN emissions provides useful insight into the identification of different molecular emitters, namely organic and inorganic CN, depending on the laser irradiance and time settings conditions. These promising results are of application in the search and identification of biosignatures in upcoming planetary missions with astrobiological purposes.

2.
Anal Chim Acta ; 1276: 341632, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37573113

RESUMO

In this work, a geological sample of great astrobiological interest was studied through analytical techniques that are currently operating in situ on Mars and others that will operate in the near future. The sample analyzed consisted of an oncoid, which is a type of microbialite, collected in the Salar Carachi Pampa, Argentina. The main peculiarity of microbialites is that they are organo-sedimentary deposits formed by the in situ fixation and precipitation of calcium carbonate due to the growth and metabolic activities of microorganisms. For this reason, the Carachi Pampa oncoid was selected as a Martian analog for astrobiogeochemistry study. In this sense, the sample was characterized by means of the PIXL-like, SuperCam-like and SHERLOC-like instruments, which represent instruments on board the NASA Perseverance rover, and by means of RLS-like and MOMA-like instruments, which represent instruments on board the future ESA Rosalind Franklin rover. It was possible to verify that the most important conclusions and discoveries have been obtained from the combination of the results. Likewise, it was also shown that Perseverance rover-like remote-sensing instruments allowed a first detailed characterization of the biogeochemistry of the Martian surface. With this first characterization, areas of interest for in-depth analysis with Rosalind Franklin-like instruments could be identified. Therefore, from a first remote-sensing elemental identification (PIXL-like instrument), followed by a remote-sensing molecular characterization (SuperCam and SHERLOC-like instruments) and ending with an in-depth microscopic analysis (RLS and MOMA-like instruments), a wide variety of compounds were found. On the one hand, the expected minerals were carbonates, such as aragonite, calcite and high-magnesium calcite. On the other hand, unexpected compounds consisted of minerals related to the Martian/terrestrial surface (feldspars, pyroxenes, hematite) and organic compounds related to the past biological activity related to the oncoid (kerogen, lipid biomarkers and carotenes). Considering samples resembling microbialites have already been found on Mars and that one of the main objectives of the missions is to identify traces of past life, the study of microbialites is a potential way to find biosignatures protected from the inhospitable Martian environment. In addition, it should be noted that in this work, further conclusions have been obtained through the study of the results as a whole, which could also be carried out on Mars.

3.
Rev Clin Esp (Barc) ; 219(6): 310-314, 2019.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30871718

RESUMO

BACKGROUND: Diagnosing pulmonary embolisms can be challenging, given that its presentation shares clinical manifestations with other conditions. For patients 80 years of age or older, the healthcare challenge increases due to associated comorbidity when compared with younger patients (<80 years). OBJECTIVE: The aim of our study was to report the incidence of pulmonary embolism in elderly patients in our setting and identify differences in the clinical manifestations, comorbidity and laboratory parameters between these 2 groups of patients. METHOD: We conducted a hospital-based, case-control study to review the pulmonary embolisms diagnosed in our centre using computed tomography pulmonary angiography between 2013 and 2016. RESULTS: The study included 413 patients, 124 of whom were 80 years of age or older, with a median age of 72 years (IQR, 58-81). The typical presentation triad was uncommon and showed no differences between subgroups. The main symptoms presented by these groups were dyspnoea (73.4% vs. 63.7% for the elderly and younger groups, respectively; P=.055), chest pain (26.6% vs. 39.5%; P=.013) and cough/haemoptysis (31.1% vs. 18.9%; P=.021). The elderly group had more comorbidity (4.88±2.55 vs. 2.89±2.85; P=.0001). CONCLUSION: Thirty percent of the pulmonary embolisms occurred in the elderly group. The typical presentation form was uncommon. We detected significant differences in individual symptoms, comorbidity and laboratory parameters compared with the younger patients.

4.
Arch. latinoam. nutr ; 50(3): 219-229, sept. 2000. tab, graf
Artigo em Espanhol | LILACS | ID: lil-305224

RESUMO

El ajo ha sido utilizado medicamente desde muy antiguo ,e incluso, todavía hoy forma parte de la medicina popular en muchas culturas. En los últimos tiempos se ha incrementado el número de estudios sobre la efectividad del ajo en la normalización de los factores de riesgo cardiovascular y sobre el papel del mismo en el tratamiento de dichas enfermedades. Trabajos recientes señalan la existencia en el ajo de gran cantidad de sustancias, muchas de ellas azufradas, con importantes aplicaciones en el campo de la salud. El objetivo de este trabajo es revisar los resultados de numerosos estudios referentes al ajo en relación con las enfermedades cardiovasculares. De alguno de ellos puede resumirse que el ajo puede promover la normalización de los lípidos plásmaticos, frenar la peroxidación lipídica, estimular la actividad fibrinolítica, inhibir la agregación plaquetaria atenuar los cambios morfoestructurales de la pared vascular relacionado con el envejecimiento o la lesión aterosclérotica de la misma, y reducir la tensión arterial. Sin embargo otros estudios recientes no apoyan dichos resultados. Estos efectos positivos han despertado numerosas expectativas en cuanto al uso del ajo en la prevención y control de la enfermedades cardiovasculares. No obstante, dada la habilidad de algunos compuestos que contiene y la falta de acuerdo en los resultados obtenidos se sugiere moderación en su consumo. La variabilidad en su composición debida al tipo de recolección y envejecimiento junto con la modificación en la composición original por el enlatado, encapsulado y tratamiento industrial hacen necesaria la aplicación de una regulación que garantice el uso en forma y dosis adecuada de este alimento funcional


Assuntos
Humanos , Masculino , Feminino , Fármacos Cardiovasculares , Alho , Proteínas/administração & dosagem , Ciências da Nutrição/educação , Espanha
5.
Arch Latinoam Nutr ; 50(3): 219-29, 2000 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-11347290

RESUMO

Garlic has been used for centuries, and even nowadays is part of popular medicine in many cultures. New data have increased the interest in garlic and its role in normalization and treatment of cardiovascular disease risk factors. Recent studies have shown the complex composition of garlic, containing many compounds, that present potential positive effect in the field of health. The aim of the present paper was to review results of some studies that have found a relationship between garlic and cardiovascular diseases. From some of them it can be summarized that garlic can normalize plasma lipid, check lipid peroxidation, stimulate fibrinolytic activity, inhibit platelet aggregation, smooth the thickening and structural changes of artery wall related to aging and atherosclerosis, and decrease blood pressure. However, some other studies do not support these benefits. The positive effects found have promoted many study projects, nevertheless, the extract lability and the lack of result consensus call for a moderate consumption of garlic and garlic extracts. The composition variation due to gathering and aging together with the changes occurring in canning and industrial treatment makes necessary the application of some norms in the production and consumption of this functional food in order to guarantee its use in adequate form and doses.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Alho/uso terapêutico , Fitoterapia , Plantas Medicinais , Animais , Arteriosclerose/sangue , Arteriosclerose/prevenção & controle , Pressão Sanguínea , Alho/química , Humanos , Hipertensão/prevenção & controle , Lipídeos/sangue , Agregação Plaquetária , Resistência Vascular
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