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1.
J Pers ; 2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37564023

RESUMEN

OBJECTIVE: This study aims to explore the reciprocal associations between personality traits (conscientiousness and openness to experience) and academic achievement in adolescents, using the Personality Achievement Saturation Hypothesis (PASH). BACKGROUND: Personality traits, especially conscientiousness, and openness, have been identified as strong predictors of academic achievement. The PASH provides a framework for understanding these relationships but has mainly been studied from a unidirectional perspective. This study extends the PASH to examine reciprocal associations and how they vary with different achievement indicators. METHODS: Using large-scale panel data (N = 6482) of secondary school students in Germany, we applied cross-lagged panel models and latent change score models to examine the differential reciprocal associations between personality traits (conscientiousness/openness) and academic achievement (school grades/achievement test scores) in language and math over two years from grades 7 to 9. RESULTS: In line with the PASH, initial levels of conscientiousness were more strongly associated with school grades than with achievement test scores over two years. Simultaneously, prior school grades were more strongly associated with conscientiousness over two years. However, initial levels of openness did not show differential associations with either school grades or achievement test scores over two years. Similarly, prior school grades and achievement test scores were also not differentially associated with openness over two years. CONCLUSIONS: Our findings introduce an innovative lens through which we observe how the PASH can be leveraged to explain the differential reciprocal associations between conscientiousness and academic achievement. Further research is needed to examine if PASH could be similarly extended to disentangle the associations between openness and academic achievement.

2.
Eur J Immunol ; 50(6): 783-794, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32065660

RESUMEN

In humans and mice, mucosal immune responses are dominated by IgA antibodies and the cytokine TGF-ß, suppressing unwanted immune reactions but also targeting Ig class switching to IgA. It had been suggested that eosinophils promote the generation and maintenance of mucosal IgA-expressing plasma cells. Here, we demonstrate that not eosinophils, but specific bacteria determine mucosal IgA production. Co-housing of eosinophil-deficient mice with mice having high intestinal IgA levels, as well as the intentional microbiota transfer induces TGF-ß expression in intestinal T follicular helper cells, thereby promoting IgA class switching in Peyer's patches, enhancing IgA+ plasma cell numbers in the small intestinal lamina propria and levels of mucosal IgA. We show that bacteria highly enriched for the genus Anaeroplasma are sufficient to induce these changes and enhance IgA levels when adoptively transferred. Thus, specific members of the intestinal microbiota and not the microbiota as such regulate gut homeostasis, by promoting the expression of immune-regulatory TGF-ß and of mucosal IgA.


Asunto(s)
Microbioma Gastrointestinal/inmunología , Inmunidad Mucosa , Inmunoglobulina A/inmunología , Mucosa Intestinal , Ganglios Linfáticos Agregados , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Mucosa Intestinal/inmunología , Mucosa Intestinal/microbiología , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Ganglios Linfáticos Agregados/inmunología , Ganglios Linfáticos Agregados/microbiología , Tenericutes/inmunología
3.
Eur Econ Rev ; 140: 103920, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34602646

RESUMEN

In spring 2020, governments around the globe shut down schools to mitigate the spread of the novel coronavirus. We argue that low-achieving students may be particularly affected by the lack of educator support during school closures. We collect detailed time-use information on students before and during the school closures in a survey of 1099 parents in Germany. We find that while students on average reduced their daily learning time of 7.4 h by about half, the reduction was significantly larger for low-achievers (4.1 h) than for high-achievers (3.7 h). Low-achievers disproportionately replaced learning time with detrimental activities such as TV or computer games rather than with activities more conducive to child development. The learning gap was not compensated by parents or schools who provided less support for low-achieving students.

4.
Int J Mol Sci ; 21(11)2020 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-32521698

RESUMEN

Triple negative human breast cancer (TNBC) is an aggressive cancer subtype with poor prognosis. Besides the better-known artemisinin, Artemisia annua L. contains numerous active compounds not well-studied yet. High-performance liquid chromatography coupled with diode-array and mass spectrometric detection (HPLC-DAD-MS) was used for the analysis of the most abundant compounds of an Artemisia annua extract exhibiting toxicity to MDA-MB-231 TNBC cells. Artemisinin, 6,7-dimethoxycoumarin, arteannuic acid were not toxic to any of the cancer cell lines tested. The flavonols chrysosplenol d and casticin selectively inhibited the viability of the TNBC cell lines, MDA-MB-231, CAL-51, CAL-148, as well as MCF7, A549, MIA PaCa-2, and PC-3. PC-3 prostate cancer cells exhibiting high basal protein kinase B (AKT) and no ERK1/2 activation were relatively resistant, whereas MDA-MB-231 cells with high basal ERK1/2 and low AKT activity were more sensitive to chrysosplenol d treatment. In vivo, chrysosplenol d and casticin inhibited MDA-MB-231 tumor growth on chick chorioallantoic membranes. Both compounds induced mitochondrial membrane potential loss and apoptosis. Chrysosplenol d activated ERK1/2, but not other kinases tested, increased cytosolic reactive oxygen species (ROS) and induced autophagy in MDA-MB-231 cells. Lysosomal aberrations and toxicity could be antagonized by ERK1/2 inhibition. The Artemisia annua flavonols chrysosplenol d and casticin merit exploration as potential anticancer therapeutics.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Artemisia annua/química , Flavonas/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Animales , Antineoplásicos Fitogénicos/química , Línea Celular Tumoral , Permeabilidad de la Membrana Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Femenino , Flavonas/química , Flavonoides/química , Flavonoides/farmacología , Flavonoles/química , Flavonoles/farmacología , Humanos , Ratones , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Neoplasias de la Mama Triple Negativas , Ensayos Antitumor por Modelo de Xenoinjerto
5.
Molecules ; 24(11)2019 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-31181656

RESUMEN

Pentacyclic triterpenic acids from oleogum resins of Boswellia species are of considerable therapeutic interest. Yet, their pharmaceutical development is hampered by uncertainties regarding botanical identification and the complexity of triterpenic acid mixtures. Here, a highly sensitive, selective, and accurate method for the simultaneous quantification of eight boswellic and lupeolic acids by high-performance liquid chromatography with tandem mass spectrometry detection (HPLC-MS/MS) was developed. The method was applied to the comparative analysis of 41 oleogum resins of the species B. sacra, B. dalzielli, B. papyrifera, B. serrata, B. carterii, B. neglecta, B. rivae, B. frereana, and B. occulta. Multivariate statistical analysis of the data revealed differences in the triterpenic acid composition that could be assigned to distinct Boswellia species and to their geographic growth location. Extracts of the oleogum resins exhibited cytotoxicity against the human, treatment-resistant, metastatic breast cancer cell line MDA-MB-231. Extracts from B. sacra were the most potent ones with an average IC50 of 8.3 ± 0.6 µg/mL. The oleogum resin of the B. sacra was further fractionated to enrich different groups of substances. The cytotoxic efficacy against the cancer cells correlates positively with the contents of pentacyclic triterpenic acids in Boswellia extracts.


Asunto(s)
Antineoplásicos Fitogénicos/análisis , Boswellia/química , Neoplasias de la Mama/tratamiento farmacológico , Triterpenos Pentacíclicos/análisis , Resinas de Plantas/análisis , Antineoplásicos Fitogénicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Resistencia a Antineoplásicos/efectos de los fármacos , Femenino , Humanos , Triterpenos Pentacíclicos/farmacología , Resinas de Plantas/farmacología , Espectrometría de Masas en Tándem , Triterpenos/aislamiento & purificación , Triterpenos/farmacología
6.
Chemistry ; 22(42): 14920-14928, 2016 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-27573447

RESUMEN

We combine density functional theory calculations and scanning tunneling microscopy investigations to identify the relevant chemical species and reactions in the nucleation phase of chemical vapor deposition. tert-Butylphosphine (TBP) was deposited on a silicon substrate under conditions typical for surface functionalization and growth of semiconductor materials. On the activated hydrogen-covered surface H/Si(001) it forms a strong covalent P-Si bond without loss of the tert-butyl group. Calculations show that site preference for multiple adsorption of TBP is influenced by steric repulsion of the adsorbate's bulky substituent. STM imaging furthermore revealed an anisotropic distribution of TBP with a preference for adsorption perpendicular to the surface dimer rows. The adsorption patterns found can be understood by a mechanism invoking stabilization of surface hydrogen vacancies through electron donation by an adsorbate. The now improved understanding of nucleation in thin-film growth may help to optimize molecular precursors and experimental conditions and will ultimately lead to higher quality materials.

7.
Microsc Microanal ; 22(1): 131-9, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26739750

RESUMEN

Melt-back etching is an effect that can occur for gallium (Ga) containing III/V semiconductors grown on Si. Since this effect influences interfaces between the two compounds and therefore the physical characteristics of the material composition, it is desirable to understand its driving forces. Therefore, we investigated Ga grown on Si (001) via metal organic chemical vapor deposition using trimethyl Ga as a precursor. As a result of the melt-back etching, Ga-containing droplets formed on the Si surface which reach into the Si wafer. The shape of these structures was analyzed by plan view investigation and cross sectional tomography in a (scanning) transmission electron microscope. For plan view preparation a focused ion beam was used to avoid damage to the Ga-containing structures, which are sensitive to the chemicals normally used during conventional plan view preparation. Combining the results of both investigation methods confirms that the Ga-containing structure within the Si exhibits a pyramid shape with facets along the Si {111} lattice planes.

8.
Cytotherapy ; 16(12): 1700-8, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25304663

RESUMEN

BACKGROUND AIMS: Complex injuries of the upper and lower extremities often result in scarring and subsequent adhesion formation, which may cause severe pain and distinctly reduce range of motion. In revision surgery, replacement of the missing subcutaneous tissue is desirable to prevent new adhesions, to cushion scarred tendons and nerves and to regain tissue elasticity. Therefore, the objective of this study was the in vitro evaluation of cell-seeded collagen matrices to serve as the basis for the reconstruction of the subcutaneous adipose tissue layer. METHODS: Five commercially available acellular dermal collagen matrices were seeded with human adipose-derived stromal cells (hASC). Size and shape stability of cell-matrix constructs were assessed and cell adhesion onto the matrix surface was evaluated histologically. Adipogenic differentiation of hASC on matrices was evaluated by means of histological staining, triglyceride quantification, and quantitative real-time polymerase chain reaction gene expression analysis. RESULTS: The collagen matrix Permacol was the only cell-seeded material that exhibited excellent size and shape stability. For Permacol and Strattice, successful seeding with continuous cell layers on top of the matrices was observed. For both matrices, histological staining, triglyceride quantification and messenger RNA expression of adipogenic transcription factors indicated substantial adipogenic differentiation of hASC after long-term induction as well as after short-term induction of only 4 days. CONCLUSIONS: Of all matrices investigated, only Permacol exhibited adequate handling stability and the development of a thin adipose tissue layer on top of the matrix. Thus, this matrix appears promising to be used in the development of a subcutaneous cushioning layer after complex injuries involving large scar formation.


Asunto(s)
Colágeno/química , Matriz Extracelular/química , Células Madre Mesenquimatosas/metabolismo , Grasa Subcutánea/metabolismo , Adulto , Técnicas de Cultivo de Célula , Células Cultivadas , Femenino , Regulación de la Expresión Génica , Humanos , Masculino , Células Madre Mesenquimatosas/citología , Persona de Mediana Edad , Grasa Subcutánea/citología
9.
Microorganisms ; 11(2)2023 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-36838273

RESUMEN

Thermophilic composting is a suitable treatment for the recycling of organic wastes for agriculture. However, using human excreta as feedstock for composting raises concerns about antibiotic resistances. We analyzed samples from the start and end of a thermophilic composting trial of human excreta, together with green cuttings and straw, with and without biochar. Beta-lactamase genes blaCTX-M, blaIMP, and blaTEM conferring resistance to broad-spectrum beta-lactam antibiotics, as well as horizontal gene transfer marker genes, intI1 and korB, were quantified using qPCR. We found low concentrations of the beta-lactamase genes in all samples, with non-significant mean decreases in blaCTX-M and blaTEM copy numbers and a mean increase in blaIMP copy numbers. The decrease in both intI1 and korB genes from start to end of composting indicated that thermophilic composting can decrease the horizontal spread of resistance genes. Thus, thermophilic composting can be a suitable treatment for the recycling of human excreta.

10.
Stud Health Technol Inform ; 301: 77-82, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37172157

RESUMEN

BACKGROUND: Aphasia describes the lack of the already gained ability to use language in a common way. "Language" here covers all variations of forming or understanding messages. OBJECTIVES: The APH-Alarm project aims to develop a service concept that provides alternative communication options for people with Aphasia to trigger timely help when needed. It considers that a typical user may not be familiar with modern technologies and offers several simple and intuitive options. METHODS: The approach is based on event detection of gestures (during daytime or in bed), movement pattern recognition in bed, and an easy-to-use pictogram-based smartphone app. RESULTS: Agile evaluation of the smartphone app showed a promising outcome. CONCLUSION: The idea of a versatile and comprehensive solution for aphasic people to easily contact private or public helpers based on their actions or automatic detection is promising and will be further investigated in an upcoming field trial.


Asunto(s)
Afasia , Equipos de Comunicación para Personas con Discapacidad , Aplicaciones Móviles , Humanos , Lenguaje , Gestos
11.
Front Psychol ; 13: 786838, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36051202

RESUMEN

The brutal wars in Iraq, Syria and now Ukraine have caused a massive influx of refugees to Europe. Turkey alone has received more than 4.8 million refugees. An important precondition for their economic and social incorporation is trust: refugees need to trust the citizens as well as the state and the justice system to find their place in the host country. Yet refugees' propensity to trust may be affected by cultural differences between their home and host countries, their personal conflict exposure and the experiences they had on the run. This study investigates how individual differences in exposure to armed conflict and institutional breakdown shape two types of trust among refugees: Generalized social trust and trust in the institutions of the settlement country. We survey a large and diverse sample of refugees from Syria and Iraq living in Turkish communities and deploy well-established measures of conflict exposure, posttraumatic stress, and posttraumatic growth. We find that higher degrees of conflict exposure are positively related to social trust, and to trust in courts and the police. These positive findings are largely driven by refugees who had very personal and emotionally powerful experiences. The psychological mechanism of posttraumatic growth cannot explain these findings, however, suggesting positive experiences of cooperation in the midst of war and displacement are potentially a better explanation for this finding than positive psychological changes resulting from trauma. At the same time, conflict exposure is negatively related to trust in political institutions. Posttraumatic stress may be the mechanism behind this result. We discuss the implications of these findings for the integration of war refugees-a topic that is tragically of great relevance today.

12.
Disabil Rehabil Assist Technol ; : 1-7, 2022 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-36301725

RESUMEN

PURPOSE: Problems with handwriting are a common referral to occupational therapy in children and are often associated with inadequate pen grip and tip pressure. Technologies providing immediate feedback on applied forces are currently not available. Therefore, the aim was to identify user's perspectives on the optimal functionality of a pressure-sensitive pen with an integrated feedback system. METHODS: To ensure that the product meets the requirements of the users, user needs of paediatric occupational therapists, elementary or special education teachers and children were collected in two focus groups and a children's workshops before starting the technical development process. Focus group transcripts were analyzed and rephrased as user stories to identify user-centred requirements. In a second step, user stories were merged and ranked regarding importance and feasibility. RESULTS: 120 user story requirements were generated from the focus groups and children's workshops, indicating requirements regarding design and functionality for the pen and mobile application. Visual feedback, appropriate size and weight, customizability, ease of settings and usability of the pen were pivotal. CONCLUSIONS: This study comprehensively researched the requirements for a device that may facilitate children in adjusting their handwriting pressure and can guide further research and evaluation.


Description of a participatory design process for the development of a pressure-sensitive pen.Understand the needs of different stakeholders for an assistive device for children with handwriting difficulties.Inform the further development of a pressure-sensitive pen with immediate pressure-feedback.

13.
Front Microbiol ; 13: 826071, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35432262

RESUMEN

In times of climate change, practicing a form of sustainable, climate-resilient and productive agriculture is of primordial importance. Compost could be one form of sustainable fertilizer, which is increasing humus, water holding capacity, and nutrient contents of soils. It could thereby strengthen agriculture toward the adverse effects of climate change, especially when additionally combined with biochar. To get access to sufficient amounts of suitable materials for composting, resources, which are currently treated as waste, such as human excreta, could be a promising option. However, the safety of the produced compost regarding human pathogens, pharmaceuticals (like antibiotics) and related resistance genes must be considered. In this context, we have investigated the effect of 140- and 154-days of thermophilic composting on the hygienization of human excreta and saw dust from dry toilets together with straw and green cuttings with and without addition of biochar. Compost samples were taken at the beginning and end of the composting process and metagenomic analysis was conducted to assess the fate of antibiotic resistance genes (ARGs) and pathogenicity factors of the microbial community over composting. Potential ARGs conferring resistance to major classes of antibiotics, such as beta-lactam antibiotics, vancomycin, the MLSB group, aminoglycosides, tetracyclines and quinolones were detected in all samples. However, relative abundance of ARGs decreased from the beginning to the end of composting. This trend was also found for genes encoding type III, type IV, and type VI secretion systems, that are involved in pathogenicity, protein effector transport into eukaryotic cells and horizontal gene transfer between bacteria, respectively. The results suggest that the occurrence of potentially pathogenic microorganisms harboring ARGs declines during thermophilic composting. Nevertheless, ARG levels did not decline below the detection limit of quantitative PCR (qPCR). Thresholds for the usage of compost regarding acceptable resistance gene levels are yet to be evaluated and defined.

14.
Front Microbiol ; 13: 824834, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35250940

RESUMEN

In times of climate change, practicing sustainable, climate-resilient, and productive agriculture is of primordial importance. Compost from different resources, now treated as wastes, could be one form of sustainable fertilizer creating a resilience of agriculture to the adverse effects of climate change. However, the safety of the produced compost regarding human pathogens, pharmaceuticals, and related resistance genes must be considered. We have assessed the effect of thermophilic composting of dry toilet contents, green cuttings, and straw, with and without biochar, on fecal indicators, the bacterial community, and antibiotic resistance genes (ARGs). Mature compost samples were analyzed regarding fecal indicator organisms, revealing low levels of Escherichia coli that are in line with German regulations for fertilizers. However, one finding of Salmonella spp. exceeded the threshold value. Cultivation of bacteria from the mature compost resulted in 200 isolates with 36.5% of biosafety level 2 (BSL-2) species. The majority is known as opportunistic pathogens that likewise occur in different environments. A quarter of the isolated BSL-2 strains exhibited multiresistance to different classes of antibiotics. Molecular analysis of total DNA before and after composting revealed changes in bacterial community composition and ARGs. 16S rRNA gene amplicon sequencing showed a decline of the two most abundant phyla Proteobacteria (start: 36-48%, end: 27-30%) and Firmicutes (start: 13-33%, end: 12-16%), whereas the abundance of Chloroflexi, Gemmatimonadetes, and Planctomycetes rose. Groups containing many human pathogens decreased during composting, like Pseudomonadales, Bacilli with Bacillus spp., or Staphylococcaceae and Enterococcaceae. Gene-specific PCR showed a decline in the number of detectable ARGs from 15 before to 8 after composting. The results reveal the importance of sufficiently high temperatures lasting for a sufficiently long period during the thermophilic phase of composting for reducing Salmonella to levels matching the criteria for fertilizers. However, most severe human pathogens that were targeted by isolation conditions were not detected. Cultivation-independent analyses also indicated a decline in bacterial orders comprising many pathogenic bacteria, as well as a decrease in ARGs. In summary, thermophilic composting could be a promising approach for producing hygienically safe organic fertilizer from ecological sanitation.

15.
J Bacteriol ; 193(5): 1191-200, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21169486

RESUMEN

Metallosphaera sedula (Sulfolobales, Crenarchaeota) uses the 3-hydroxypropionate/4-hydroxybutyrate cycle for autotrophic carbon fixation. In this pathway, acetyl-coenzyme A (CoA) and succinyl-CoA are the only intermediates that can be considered common to the central carbon metabolism. We addressed the question of which intermediate of the cycle most biosynthetic routes branch off. We labeled autotrophically growing cells by using 4-hydroxy[1-¹4C]butyrate and [1,4-¹³C1]succinate, respectively, as precursors for biosynthesis. The labeling patterns of protein-derived amino acids verified the operation of the proposed carbon fixation cycle, in which 4-hydroxybutyrate is converted to two molecules of acetyl-CoA. The results also showed that major biosynthetic flux does not occur via acetyl-CoA, except for the formation of building blocks that are directly derived from acetyl-CoA. Notably, acetyl-CoA is not assimilated via reductive carboxylation to pyruvate. Rather, our data suggest that the majority of anabolic precursors are derived from succinyl-CoA, which is removed from the cycle via oxidation to malate and oxaloacetate. These C4intermediates yield pyruvate and phosphoenolpyruvate (PEP). Enzyme activities that are required for forming intermediates from succinyl-CoA were detected, including enzymes catalyzing gluconeogenesis from PEP. This study completes the picture of the central carbon metabolism in autotrophic Sulfolobales by connecting the autotrophic carbon fixation cycle to the formation of central carbon precursor metabolites.


Asunto(s)
Proteínas Bacterianas/metabolismo , Ciclo del Carbono/fisiología , Carbono/metabolismo , Regulación Bacteriana de la Expresión Génica/fisiología , Regulación Enzimológica de la Expresión Génica/fisiología , Sulfolobaceae/enzimología , Aminoácidos/metabolismo , Proteínas Bacterianas/genética , Isótopos de Carbono , Metabolismo Energético , Sulfolobaceae/metabolismo
16.
J Health Econ ; 76: 102440, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33640855

RESUMEN

We integrate time-inconsistent decision making due to hyperbolic discounting into a gerontologically founded life cycle model with endogenous aging and longevity. Individuals can slow down aging and postpone death by health investments and by reducing unhealthy consumption, conceptualized as smoking. We show that individuals continuously revise their original plans to smoke less and invest more in their health. Consequently, they accumulate health deficits faster and die earlier than originally planned. This fundamental health consequence of time-inconsistency has not been addressed in the literature so far. Because death is endogenous, any attempt to establish the time-consistent first-best solution by manipulating the first order conditions through (sin-) taxes and subsidies is bound to fail. We calibrate the model with U.S. data for an average American in the year 2012 and estimate that time-inconsistent health behavior causes a loss of about 4 years of life. We show how price policy can nudge individuals to behave more healthy such that they actually realize the longevity and value of life planned at age 20.


Asunto(s)
Envejecimiento , Longevidad , Adulto , Conductas Relacionadas con la Salud , Estado de Salud , Humanos , Impuestos , Adulto Joven
17.
Sci Rep ; 10(1): 16830, 2020 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-33033361

RESUMEN

Loess-paleosol sequences are terrestrial archives of past climate change. They may host traces of ancient microbial life, but little information is available on the recovery of microbial biomarkers from such deposits. We hypothesized that microbial communities in soil horizons up to an age of 127 kyr carry information related to past environments. We extracted DNA from a loess-paleosol sequence near Toshan, Northern Iran, with 26 m thick deposits showing different degrees of soil development, performed quantitative PCR and 16S rRNA gene amplicon sequencing. Periods of soil formation archived within the loess sediment led to higher diversity and bacterial abundance in the paleosol horizons. Community composition fluctuated over the loess-paleosol sequence and was mainly correlated with age and depth, (ADONIS R2 < 0.14, P ≤ 0.002), while responses to paleosol soil traits were weaker. Phyla like Bacteriodetes, Proteobacteria or Acidobacteria were more prevalent in paleosol horizons characterized by intense soil formation, while weakly developed paleosols or loess horizons hosted a higher percentage and diversity of Actinobacteria. Taken together, our findings indicate that the microbial community in loess-paleosol sequences carries signatures of earlier environmental conditions that are preserved until today.


Asunto(s)
Bacterias/genética , Cambio Climático , Microbiología del Suelo , Ambiente , Amplificación de Genes , Paleontología , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética
18.
Nutrients ; 11(10)2019 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-31581678

RESUMEN

For centuries, frankincense extracts have been commonly used in traditional medicine, and more recently, in complementary medicine. Therefore, frankincense constituents such as boswellic and lupeolic acids are of considerable therapeutic interest. Sixteen frankincense nutraceuticals were characterized by high-performance liquid chromatography with tandem mass spectrometry (HPLC-MS/MS), revealing major differences in boswellic and lupeolic acid compositions and total contents, which varied from 0.4% to 35.7%. Frankincense nutraceuticals significantly inhibited the release of proinflammatory cytokines, such as TNF-α, IL-6, and IL-8, by LPS-stimulated peripheral blood mononuclear cells (PBMC) and whole blood. Moreover, boswellic and lupeolic acid contents correlated with TNF-α, IL-1ß, IL-6, IL-8, and IL-10 inhibition. The nutraceuticals also exhibited toxicity against the human triple-negative breast cancer cell lines MDA-MB-231, MDA-MB-453, and CAL-51 in vitro. Nutraceuticals with total contents of boswellic and lupeolic acids >30% were the most active ones against MDA-MB-231 with a half maximal inhibitory concentration (IC50) ≤ 7.0 µg/mL. Moreover, a frankincense nutraceutical inhibited tumor growth and induced apoptosis in vivo in breast cancer xenografts grown on the chick chorioallantoic membrane (CAM). Among eight different boswellic and lupeolic acids tested, ß-ABA exhibited the highest cytotoxicity against MDA-MB-231 with an IC50 = 5.9 µM, inhibited growth of cancer xenografts in vivo, and released proinflammatory cytokines. Its content in nutraceuticals correlated strongly with TNF-, IL-6, and IL-8 release inhibition.


Asunto(s)
Antiinflamatorios/farmacología , Antineoplásicos Fitogénicos/farmacología , Citocinas/metabolismo , Olíbano/farmacología , Leucocitos Mononucleares/efectos de los fármacos , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Triterpenos/farmacología , Animales , Antiinflamatorios/análisis , Antineoplásicos Fitogénicos/análisis , Apoptosis , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Embrión de Pollo , Citocinas/inmunología , Relación Dosis-Respuesta a Droga , Femenino , Olíbano/análisis , Humanos , Concentración 50 Inhibidora , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Masculino , Neoplasias de la Mama Triple Negativas/patología , Triterpenos/análisis
19.
Phytomedicine ; 62: 152962, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31132755

RESUMEN

BACKGROUND: Artemisia annua L. has gained increasing attention for its anticancer activity. However, beside artemisinin, less is known about the possible bioactive ingredients of Artemisia annua and respective herbal preparations. We hypothesized that, in addition to artemisinin, Artemisia annua preparations might contain multiple ingredients with potential anticancer activity. METHODS: MDA-MB-231 triple negative human breast cancer (TNBC) cells along with other treatment resistant, metastatic cancer cell lines were used to investigate in vitro and in vivo the anticancer efficacy of an Artemisia annua extract marketed as a herbal preparation, which contained no detectable artemisinin (limit of detection = 0.2 ng/mg). The extract was characterized by HPLC-DAD and the most abundant compounds were identified by 1H- and 13C NMR spectroscopy and quantified by UHPLC-MS/MS. Cell viability and various apoptotic parameters were quantified by flow cytometry. In vitro data were validated in two in vivo cancer models, the chick chorioallantoic membrane (CAM) assay and in orthotopic breast cancer xenografts in nude mice. RESULTS: The Artemisia annua extract, the activity of which could be enhanced by acetonitrile maceration, inhibited the viability of breast (MDA-MB-231 and MCF-7), pancreas (MIA PaCa-2), prostate (PC-3), non-small cell lung cancer (A459) cells, whereas normal mammary epithelial cells, lymphocytes, and PBMC were relatively resistant to extract treatment. Likewise, the extract's most abundant ingredients, chrysosplenol D, arteannuin B, and casticin, but not arteannuic acid or 6,7-dimethoxycoumarin, inhibited the viability of MDA-MB-231 breast cancer cells. The extract induced accumulation of multinucleated cancer cells within 24 h of treatment, increased the number of cells in the S and G2/M phases of the cell cycle, followed by loss of mitochondrial membrane potential, caspase 3 activation, and formation of an apoptotic hypodiploid cell population. Further, the extract inhibited cancer cell proliferation, decreased tumor growth, and induced apoptosis in vivo in TNBC MDA-MB-231 xenografts grown on CAM as well as in nude mice. CONCLUSION: An extract of an artemisinin-deficient Artemisia annua herbal preparation exhibits potent anticancer activity against triple negative human breast cancer. New active ingredients of Artemisia annua extract with potential anticancer activity have been identified.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Artemisia annua/química , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Extractos Vegetales/farmacología , Animales , Antineoplásicos Fitogénicos/química , Apoptosis/efectos de los fármacos , Artemisininas/química , Neoplasias de la Mama , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Femenino , Flavonas/química , Flavonoides/química , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Ratones , Ratones Desnudos , Extractos Vegetales/química , Ensayos Antitumor por Modelo de Xenoinjerto
20.
PLoS One ; 13(11): e0206666, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30485306

RESUMEN

Previous laboratory studies on the centipede game have found that subjects exhibit surprisingly high levels of cooperation. Across disciplines, it has recently been highlighted that these high levels of cooperation might be explained by "team reasoning", the willingness to think as a team rather than as an individual. We run an experiment with a standard centipede game as a baseline. In two treatments, we seek to induce team reasoning by making a joint goal salient. First, we implement a probabilistic variant of the centipede game that makes it easy to identify a joint goal. Second, we frame the game as a situation where a team of two soccer players attempts to score a goal. This frame increases the salience even more. Compared to the baseline, our treatments induce higher levels of cooperation. In a second experiment, we obtain similar evidence in a more natural environment-a beer garden during the 2014 FIFA Soccer World Cup. Our study contributes to understanding how a salient goal can support cooperation.


Asunto(s)
Conducta Cooperativa , Procesos de Grupo , Pensamiento , Adulto , Animales , Artrópodos , Femenino , Teoría del Juego , Juegos Experimentales , Humanos , Masculino , Probabilidad , Fútbol/psicología , Adulto Joven
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