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Carbon and Nitrogen Isotopic Signatures of Hair, Nail, and Breath from tropical African Human Populations
RATIONALE: Stable isotopic analyses are increasingly used to study the diets of past and present human populations. Yet, the carbon and nitrogen isotopic data of modern human diets collected so far are biased towards Europe and North America. Here, we address this gap by reporting on the dietary isotopic signatures of six tropical African communities: El Molo, Turkana (Kerio), Luhya (Webuye), Luhya (Port Victoria), and Luo (Port Victoria) from Kenya, and Baka from Cameroon; representing four subsistence strategies: fishing, pastoralism, agriculturalism, and hunter-gatherer. METHODS: We used EA-CF-IRMS to measure the carbon and nitrogen isotopic ratios of hair (n = 134) and nail (n = 80), and the carbon isotopic ratios of breath (n = 184) from these communities, as well as the carbon and nitrogen isotopic ratios of some food samples from the Kenyan communities. RESULTS: We expand on the known range of δ13 C values in human hair through the hunter-gatherer Baka, with a diet based on C3 plants, and through the agriculturalist Luhya (Webuye), with a diet based on C4 plants. In addition, we found that the consumption of fish from East African lakes is difficult to detect isotopically due to the combined effects of high nitrogen isotopic ratios of plants and the low nitrogen isotopic ratios of fish. Finally, we found that some of the communities studied are markedly changing their diets through increasing sedentism and urbanization. CONCLUSION: Our findings contribute substantially to the understanding of the environmental, demographic and economic dynamics that affect the dietary landscape of different tropical populations of Africa. These results highlight the importance of studying a broader sample of human populations and their diet, with a focus on their precise context - both from an isotopic and more general anthropological perspectives.This study was funded by a European Research Council Advanced Award to MML (In-Africa Project, ERC 295907), and carried out with permission from the National Commission for Science, Technology and Innovation, Kenya, No. NACOSTI/P/15/2669/4758
Exercise during pregnancy on maternal lipids: A secondary analysis of randomized controlled trial
Background: Today, scientific evidence has supported the popular belief that physical activity is associated with biological health in pregnant women. A randomized controlled trial was used to assess the benefits of physical exercise during pregnancy on maternal lipids in low-income Latina women. Methods: The study included 67 nulliparous low-income Latina women in gestational weeks 16-20, randomly assigned into one of two groups: 1) The exercise group, which took part in aerobic and resistance exercise for 60min, three times a week for 12weeks, 2) The control group, which undertook their usual physical activity and prenatal care. The primary outcomes were changes in maternal blood lipids after intervention. Obstetrical and neonatal outcomes measured were type of delivery, postpartum hemorrhage, newborn and/or maternal complications', gestational age, weight gain, birth weight, foetal growth, and Apgar score. Results: Fifty women completed the study. At the end of the intervention, there were differences between groups in low-density lipoprotein levels (mean change: -8mg/dL, 95%CI -3 to -29; P less than 0.001) and triglycerides (mean change: -6mg/dL, 95%CI -1 to -11; P=0.03). Also, compared with women who remained in the control group, active women showed lower complications during delivery (moderate postpartum haemorrhage) (58% compared with 75%; P less than 0.05) and lower complications in newborns (e.g. cyanosis or respiratory distress) (21% compared with 46%; P less than 0.001). Conclusions: An exercise programme during the second and third trimester favours less gain in low-density lipoprotein cholesterol and triglycerides fewer delivery and neonatal complications. Trial registration:NCT00741312(August 22, 2008). © 2017 The Author(s)
Virtual Screening of Plant Volatile Compounds Reveals a High Affinity of Hylamorpha elegans (Coleoptera: Scarabaeidae) Odorant-Binding Proteins for Sesquiterpenes From Its Native Host
Indexación: Web of ScienceHylamorpha elegans (Burmeister) is a native Chilean scarab beetle considered to be a relevant agricultural pest to pasture and cereal and small fruit crops. Because of their cryptic habits, control with conventional methods is difficult; therefore, alternative and environmentally friendly control strategies are highly desirable. The study of proteins that participate in the recognition of odorants, such as odorant-binding proteins (OBPs), offers interesting opportunities to identify new compounds with the potential to modify pest behavior and computational screening of compounds, which is commonly used in drug discovery, may help to accelerate the discovery of new semiochemicals. Here, we report the discovery of four OBPs in H. elegans as well as six new volatiles released by its native host Nothofagus obliqua (Mirbel). Molecular docking performed between OBPs and new and previously reported volatiles from N. obliqua revealed the best binding energy values for sesquiterpenic compounds. Despite remarkable divergence at the amino acid level, three of the four OBPs evaluated exhibited the best interaction energy for the same ligands. Molecular dynamics investigation reinforced the importance of sesquiterpenes, showing that hydrophobic residues of the OBPs interacted most frequently with the tested ligands, and binding free energy calculations demonstrated van der Waals and hydrophobic interactions to be the most important. Altogether, the results suggest that sesquiterpenes are interesting candidates for in vitro and in vivo assays to assess their potential application in pest management strategies.http://jinsectscience.oxfordjournals.org/content/16/1/3
Immunology and Oxidative Stress in Multiple Sclerosis: Clinical and Basic Approach
Multiple sclerosis (MS) exhibits many of the hallmarks of an inflammatory autoimmune disorder including breakdown of the
blood-brain barrier (BBB), the recruitment of lymphocytes, microglia, and macrophages to lesion sites, the presence of multiple lesions, generally
being more pronounced in the brain stem and spinal cord, the predominantly perivascular location of lesions, the temporal maturation of lesions from
inflammation through demyelination, to gliosis and partial remyelination, and the presence of immunoglobulin in the central nervous system and cerebrospinal fluid. Lymphocytes activated in the periphery infiltrate the central nervous system to trigger a local immune response that ultimately damages myelin and axons. Pro-inflammatory cytokines amplify the inflammatory cascade by compromising the BBB, recruiting immune cells from the periphery,
and activating resident microglia. inflammation-associated oxidative burst in activated microglia and macrophages plays an important role in the demyelination and free radical-mediated
tissue injury in the pathogenesis of MS. The inflammatory environment in demyelinating lesions leads to the generation of oxygen- and nitrogen-free radicals as well as proinflammatory cytokines which contribute to the development and progression of the disease. Inflammation can lead to oxidative stress and vice versa. Thus, oxidative stress and inflammation are involved in a self-perpetuating cycle
Environmental assessment of electrochemical energy storage device manufacturing to identify drivers for attaining goals of sustainable materials 4.0
Electricity from the combination of photovoltaic panels and wind turbines exhibits potential benefits towards the sustainable cities transition. Nevertheless, the highly fluctuating and intermittent character limits an extended applicability in the energy market. Particularly, batteries represent a challenging approach to overcome the existing constraints and to achieve sustainable urban energy development. On the basis of the market roll-out and level of technological maturity, five commercially available battery technologies are assessed in this work, namely, lead-acid, lithium manganese oxide, nickel-cadmium, nickel-metal hydride, and vanadium redox flow. When considering sustainable development, environmental assessments provide valuable information. In this vein, an environmental analysis of the technologies is conducted using a life cycle assessment methodology from a cradle-to-gate perspective. A comparison of the environmental burden of battery components identified vanadium redox flow battery as the lowest environmental damage battery. In terms of components, electrodes; the electrolyte; and the set of pumps, motors, racks, and bolts exhibited the greatest environmental impact related to manufacturing. In terms of materials, copper, steel, sulphuric acid, and vanadium were identified as the main contributors to the midpoint impact categories. The results have highlighted that challenging materials 4.0 are still needed in battery manufacturing to provide sustainable technology designs required to the future urban planning based on circular economy demands
Nanostructured supramolecular hydrogels: Towards the topical treatment of Psoriasis and other skin diseases
Supramolecular hydrogels were synthesized using a bis-imidazolium based amphiphile, and incorporating chemically diverse drugs, such as the cytostatics gemcitabine hydrochloride and methotrexate sodium salt, the immunosuppressive drug tacrolimus, as well as the corticoid drugs betamethasone 17-valerate and triamcinolone acetonide, and their potential as drug delivery agents in the dermal treatment of Psoriasis was evaluated. The rheological behavior of gels was studied, showing in all cases suitable viscoelastic properties for topical drug delivery. Scanning electron microscopy (SEM) shows that the drugs included have a great influence on the gel morphology at the microscopic level, as the incorporation of gemcitabine hydrochloride leads to slightly thicker fibers, the incorporation of tacrolimus induces flocculation and spherical precipitates, and the incorporation of methotrexate forms curled fibers. 1H NMR spectroscopy experiments show that these drugs not only remain dissolved at the interstitial space, but up to 72% of either gemcitabine or methotrexate, and up to 38% of tacrolimus, is retained within the gel fibers in gels formed with a 1:1 gelator:drug molar ratio. This unique fiber incorporation not only protects the drug from degradation, but also importantly induces a Two Phase Exponential drug release, where the first phase corresponds to the drug dissolved in the interstitial space, while the second phase corresponds to the drug exiting from the gel fibers, and where the speed in each phase is in accordance with the physicochemical properties of the drugs, opening perspectives for controlled delivery. Skin permeation ex vivo tests show how these gels successfully promote the drug permeation and retention inside the skin for reaching their therapeutic target, while in vivo experiments demonstrate that they decrease the hyperplasia and reduce the macroscopic tissue damage typically observed in psoriatic skin, significantly more than the drugs in solution. All these characteristics, beside the spontaneous and easy preparation (room temperature and soft stirring), make these gels a good alternative to other routes of administration for Psoriasis treatment, increasing the drug concentration at the target tissue, and minimizing side effects
A comparison of the peers method and traditional methodologies, and risk behaviors in studies of the prevalence of drug consumption in a population of female, chilean students
Este estudio investiga el consumo de drogas y los comportamientos de riesgo de alumnas entre los 8º y 12º cursos en dos comunidades de la ciudad de Santiago, Chile. Empleando dos métodos para investigar el consumo, y basándonos en los estudios de poblaciones universitarias, hipotetizamos que los autoinformes de las alumnas sobre su consumo de drogas legales tenderán a ser consistentes con el uso real de dichas drogas, mientras que su consumo de drogas ilícitas será susceptible y tenderán a infra-informar de ello cuando se evalúa a través de medidas tradicionales de autoinforme. Para comparar los dos métodos, se diseñó un estudio transversal que compararía el consumo informado, primero empleando el método de pares, y después por medio del autoinforme tradicional, en un grupo de 350 alumnas. Los resultados muestran que los informes de las chicas sobre su consumo de drogas legales convergen empleando los dos métodos, mientras que, como se ha sugerido, infra-informaban sobre su consumo de drogas ilegales cuando se empleaban metodologías tradicionales.The present study investigates drug consumption and risk behaviors among female students between 8th and 12th grade in two communities in the city of Santiago, Chile. Based on studies of university populations, we hypothesize that the students’ reports of their consumption of licit drugs will tend to be consistent with their actual use of said drugs using two methods to investigate consumption, while their consumption of illicit drugs will be susceptible, and will tend to be under reported when evaluated through traditional self-report measures. In order to compare the two methods, a cross-sectional study was designed that would compare reported drug consumption, first using the peers method, and then by means of traditional self-report in a group of 350 students. The results show that women’s reports of licit drug consumption converge using the two methods, while as earlier suggested, women’s illicit drug consumption was found to be under reported when traditional methodologies were used
Understanding the effects of Cr doping in rutile TiO₂ by DFT calculations and X-ray spectroscopy
The effects of Cr on local environment and electronic structure of rutile TiO₂ are studied combining theoretical and experimental approaches. Neutral and negatively charged substitutional Cr impurities Cr_(Ti)(0)* and Cr_(Ti)(-1)* as well as Cr-oxygen vacancy complex 2Cr_(Ti) + V₀ are studied by the density functional theory (DFT) within the generalized gradient approximation (GGA) of Perdew-Burke-Ernzerhof (PBE) functional. Experimental results based on X-Ray absorption spectroscopy (XAS) and X-Ray photoelectron spectroscopy (XPS) performed on Cr doped TiO₂ at the Synchrotron facility were compared to the theoretical results. It is shown that the electrons of the oxygen vacancy tend to be localized at the t_(2g) states of the Cr ions in order to reach the stable oxidation state of Cr(3+)*. Effects of Cr on crystal field (CF) and structural distortions in the rutile TiO₂ cell were analyzed by the DFT calculations and XAS spectra revealing that the CF and tetragonal distortions in TiO₂ are very sensitive to the concentration of Cr
NADPH oxidase 1 as a new regulator of the WNT pathway and the protective effect of vitamin D in colorectal cancer
Trabajo presentado en el 43rd Annual Meeting of the SEBBM, celebrado en Barcelona (España) del 19 al 22 de julio de 2021.Worldwide, colorectal cancer (CRC) is the third most common malignant neoplasm and the second leading cause of cancer-associated mortality, with an estimated increase in global prevalence of 60% by 2030 (1,2). Mutational inactivation of adenomatous polyposis coli (APC) is the hallmark of CRC and leads to an overactivation of WNT signaling that favors the development and progression of CRC (3). Large epidemiological studies suggest that the diabetic population is at increased risk for site-specific cancers, including CRC (4). Our laboratory has shown that hyperglycemia induces the accumulation of ROS in CRC but not healthy cells, driving the activation of a newly described ROS/AMPK/EP300 axis that enhances Wnt/b-catenin signaling. Increased EP300 leads to increased acetylation of β-catenin at K354, a requirement for nuclear accumulation and transcriptional activation of WNT target genes (5,6). The critical role driven by ROS suggest a possible involvement of the NADPH oxidases (NOX family, as a source of ROS. Specifically, NOX 1 and NOX 4 are expressed in colon epithelial cells, and their overexpression in CRC cells promotes cell proliferation and invasiveness (7,8,9,10). Our results indicate that hyperglycemia significantly increases NOX1 levels, in correlation with increased ROS production in CRC cells, suggesting a possible regulation of the ROS/ AMPK/EP300 axis by NOX1. Antioxidant mechanisms dealing with NOX1-induced ROS should be effective against CRC. Vitamin D (1α, 25-dihydroxyvitamin D3) is a powerful antioxidant that inhibits proliferation and promotes differentiation of CRC cells at least partially through inhibition of Wnt/β-catenin signalling. Consequently, vitamin D deficiency is associated with poor survival to CRC (11,12). Our results indicate that vitamin D causes a reduction in the levels and / or activity of some members of the NOX family by turning off the ROS/AMPK/EP300/β-catenin axis and its proliferative and tumorigenic effects. The data suggest a new antitumor mechanism of vitamin D linked to its anti-oxidant action. Our results integrate independent epidemiological links between vitamin D deficiency, diabetes and cancer in one overarching and unifying mechanism
Alteraciones de la aorta ascendente en un modelo animal espontáneo de válvula aórtica bicúspide
La válvula aórtica bicúspide (VAB) es la malformación cardiaca congénita más prevalente y se asocia frecuentemente con dilatación de la aorta ascendente (DAA). Existen dos
hipótesis etiológicas sobre esta asociación: 1) genética: VAB y alteraciones estructurales de la pared aórtica son el resultado de un mismo defecto embrionario; 2) hemodinámica:
alteraciones del flujo causadas por el defecto valvular provocan la aortopatía. El sustrato histopatológico de la DAA es la necrosis cística de la media (NCM): disrupción de las lamelas
elásticas, muerte de las células musculares lisas, acúmulo de sustancia basófila en áreas acelulares, ausencia de fibrosis o inflamación. Se desconoce si durante la patogénesis de la
DAA, la disrupción de la elástica precede a la muerte celular o si esta última es la causa original.
Contamos con el único modelo animal espontáneo de VAB, consistente en una cepa consanguínea de hámsteres con una incidencia de VAB cercana al 40% (CE). Hemos investigado la
anatomía e histología de la aorta en 148 animales de la CE y 71 de una cepa control (CC), desde la juventud a la senectud.
En los animales de la CC, el diámetro de la aorta ascendente aumentó progresivamente con la edad (incremento del 22% en 1,5 años), mientras que en los de la CE permaneció
constante hasta la vejez (15 meses), pero aumentó súbita y significativamente (19%) en los últimos 3 meses. Comparada con la CC, la media aórtica de los hámsteres adultos de la CE
presentó mayor grosor, número de lamelas, grado de ondulación de las lamelas y muerte de las células musculares lisas. La muerte celular originó áreas acelulares con acúmulo de
sustancia basófila, sin presencia de inflamación ni fibrosis. No se detectó disrupción de las lamelas elásticas. Las diferencias observadas fueron de tipo cuantitativo, no cualitativo, y se
detectaron entre animales de la CE y la CC, pero no entre animales de la CE con VAB o con VAT.
Presentamos el primer modelo animal espontáneo de alteraciones de la aorta asociadas a la VAB. Nuestros resultados indican que la NCM es una proceso degenerativo de la aorta
asociado a la senectud, cuyo factor desencadenante es la muerte de las células musculares lisas. El hecho de que los hámsteres consanguíneos de la CE presenten alteraciones en la aorta
independientemente del morfotipo valvular apoya la hipótesis genética sobre la asociación entre VAB y DAA.Universidad de Málaga. Campus de Excelencia. Internacional Andalucía Tech. P10-CTS-6068 (Junta de Andalucía. Red de Investigación Cardiovascular (RIC; RETICs
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