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1.
PLoS Genet ; 19(12): e1011080, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38091369

RESUMO

Despite our increasing knowledge of molecular mechanisms guiding various aspects of human reproduction, those underlying human primordial germ cell (PGC) development remain largely unknown. Here, we conducted custom CRISPR screening in an in vitro system of human PGC-like cells (hPGCLCs) to identify genes required for acquisition and maintenance of PGC fate. Amongst our candidates, we identified TCL1A, an AKT coactivator. Functional assessment in our in vitro hPGCLCs system revealed that TCL1A played a critical role in later stages of hPGCLC development. Moreover, we found that TCL1A loss reduced AKT-mTOR signaling, downregulated expression of genes related to translational control, and subsequently led to a reduction in global protein synthesis and proliferation. Together, our study highlights the utility of CRISPR screening for human in vitro-derived germ cells and identifies novel translational regulators critical for hPGCLC development.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Proteínas Proto-Oncogênicas c-akt , Humanos , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Diferenciação Celular/genética , Células Germinativas/metabolismo , Transcriptoma
2.
Gut ; 72(12): 2294-2306, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37591698

RESUMO

OBJECTIVE: Colorectal cancer (CRC) is a leading cause of cancer-related deaths, with the majority of cases initiated by inactivation of the APC tumour suppressor. This results in the constitutive activation of canonical WNT pathway transcriptional effector ß-catenin, along with induction of WNT feedback inhibitors, including the extracellular palmitoleoyl-protein carboxylesterase NOTUM which antagonises WNT-FZD receptor-ligand interactions. Here, we sought to evaluate the effects of NOTUM activity on CRC as a function of driver mutation landscape. DESIGN: Mouse and human colon organoids engineered with combinations of CRC driver mutations were used for Notum genetic gain-of-function and loss-of-function studies. In vitro assays, in vivo endoscope-guided orthotopic organoid implantation assays and transcriptomic profiling were employed to characterise the effects of Notum activity. Small molecule inhibitors of Notum activity were used in preclinical therapeutic proof-of-principle studies targeting oncogenic Notum activity. RESULTS: NOTUM retains tumour suppressive activity in APC-null adenomas despite constitutive ß-catenin activity. Strikingly, on progression to adenocarcinoma with P53 loss, NOTUM becomes an obligate oncogene. These phenotypes are Wnt-independent, resulting from differential activity of NOTUM on glypican 1 and 4 in early-stage versus late-stage disease, respectively. Ultimately, preclinical mouse models and human organoid cultures demonstrate that pharmacological inhibition of NOTUM is highly effective in arresting primary adenocarcinoma growth and inhibiting metastatic colonisation of distal organs. CONCLUSIONS: Our findings that a single agent targeting the extracellular enzyme NOTUM is effective in treating highly aggressive, metastatic adenocarcinomas in preclinical mouse models and human organoids make NOTUM and its glypican targets therapeutic vulnerabilities in advanced CRC.


Assuntos
Adenocarcinoma , Neoplasias Colorretais , Humanos , Camundongos , Animais , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Mutação , Via de Sinalização Wnt/genética , Cateninas/genética , Cateninas/metabolismo , Cateninas/farmacologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética
3.
Theor Appl Genet ; 136(4): 70, 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36952091

RESUMO

KEY MESSAGE: We documented changes in the wheat genome attributed to genomic selection including loss of diversity, and changes in population structure and linkage disequilibrium patterns. We conclude that training and prediction populations need to co-evolve instead of the use of a static training population. Genomic selection (GS) is widely used in plant breeding to shorten breeding cycles. Our objective was to assess the impact of rapid cycling GS on the wheat genome. We used 3927 markers to genotype a training population (YTP) and individuals from five cycles (YC1-YC5) of GS for grain yield. We assessed changes of allele frequency, genetic distance, population structure, and linkage disequilibrium (LD). We found 27.3% of all markers had a significant allele frequency change by YC5, 18% experienced a significant change attributed to selection, and 9.3% had a significant change due to either drift or selection. A total of 725 of 3927 markers were fixed by YC5 with selection fixing 7.3% of the 725 markers. The genetic distance between cycles increased over time. The Fst value of 0.224 between YTP and YC5 indicates their relationship was low. The number LD blocks decreased over time and the correlation between LD matrices also decreased over time. Overall, we found a reduction in genetic diversity, increased genetic differentiation of cycles from the training population, and restructuring of the LD patterns over cycles. The accuracy of GS depends on the genomic similarity of the training population and the prediction populations. Our results show that the similarity can decline rapidly over cycles of GS and compromise the predictive ability of the YTP-based model. Our results support implementing a GS scheme where the training and prediction populations co-evolve instead of the use of a static training population.


Assuntos
Seleção Genética , Triticum , Humanos , Triticum/genética , Fenótipo , Melhoramento Vegetal/métodos , Genótipo , Genômica/métodos , Genoma de Planta , Modelos Genéticos , Polimorfismo de Nucleotídeo Único
4.
J Asthma ; : 1-9, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37999625

RESUMO

Introduction: The multiple forced expiratory maneuvers that must be performed during methacholine test require a high degree of collaboration and can lead to fatigue. However, impulse oscillometry (IOS) is a noninvasive test, quick and easy to perform, that does not require effort-dependent maneuvers.Objectives: The primary endpoint was to evaluate the relationship between IOS and spirometry during the methacholine test. The secondary endpoint was to study the predictive value of baseline IOS in the development of bronchial hyperreactivity.Methods: Observational, prospective, cross-sectional study, with recruitment of consecutive patients from the pulmonology department with clinical suspicion of bronchial asthma with negative bronchodilator test and normal FeNO.Results: Twenty-five patients were included, with a mean age of 49 ± 18 years. Thirteen patients (52%) had a positive methacholine test. The correlation between IOS indices and FEV1 was significant (p < 0.05) in all cases. The indices with the highest predictive power were R5-20 and AX. The optimal cutoff points were an increase of greater than 32.96% in R5, greater than 120.83% for X5, an increase of 30.30 [kPa l-1s-1] in R5-20, and an increase of 1.01 [kPa l-1] for AX. Baseline oscillometry demonstrated a strong predictive value in the development of bronchial hyperreactivity, with a sensitivity of 61.5% and a specificity of 91.7%, using the cut-off point of 160.0% for R5.Conclusions: IOS may be a valuable alternative to forced spirometry in detecting bronchial hyperreactivity during the methacholine test, showing a good correlation between both tests.

5.
Proc Biol Sci ; 289(1976): 20220598, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35703045

RESUMO

Fat-storing hibernators rely on fatty acids from white adipose tissue (WAT) as an energy source to sustain hibernation. Whereas arctic and temperate hibernators preferentially recruit dietary polyunsaturated fatty acids (PUFAs), tropical hibernators can rely on monounsaturated fatty acids that produce fewer lipid peroxides during oxidation. Nevertheless, compositional data on WAT from tropical hibernators are scant and questions remain regarding fat recruitment and metabolism under different environmental conditions. We analyse fatty acid profiles from the WAT of captive dwarf lemurs (Cheirogaleus medius) subjected to high-sugar or high-fat diets during fattening and cold or warm conditions during hibernation. Dwarf lemurs fed high-sugar (compared to high-fat) diets displayed WAT profiles more comparable to wild lemurs that fatten on fruits and better depleted their fat reserves during hibernation. One PUFA, linoleic acid, remained elevated before hibernation, potentially lingering from the diets provisioned prior to fattening. That dwarf lemurs preferentially recruit the PUFA linoleic acid from diets that are naturally low in availability could explain the discrepancy between captive and wild lemurs' WAT. While demonstrating that minor dietary changes can produce major changes in seasonal fat deposition and depletion, our results highlight the complex role for PUFA metabolism in the ecology of tropical hibernators.


Assuntos
Cheirogaleidae , Hibernação , Tecido Adiposo/metabolismo , Tecido Adiposo Branco/metabolismo , Animais , Ácidos Graxos , Ácidos Graxos Insaturados/metabolismo , Frutas , Ácidos Linoleicos/metabolismo , Açúcares/metabolismo
6.
Brain ; 144(6): 1670-1683, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-33723591

RESUMO

The concerted actions of the CNS and the immune system are essential to coordinating the outcome of neuroinflammatory responses. Yet, the precise mechanisms involved in this crosstalk and their contribution to the pathophysiology of neuroinflammatory diseases largely elude us. Here, we show that the CNS-endogenous hedgehog pathway, a signal triggered as part of the host response during the inflammatory phase of multiple sclerosis and experimental autoimmune encephalomyelitis, attenuates the pathogenicity of human and mouse effector CD4 T cells by regulating their production of inflammatory cytokines. Using a murine genetic model, in which the hedgehog signalling is compromised in CD4 T cells, we show that the hedgehog pathway acts on CD4 T cells to suppress the pathogenic hallmarks of autoimmune neuroinflammation, including demyelination and axonal damage, and thus mitigates the development of experimental autoimmune encephalomyelitis. Impairment of hedgehog signalling in CD4 T cells exacerbates brain-brainstem-cerebellum inflammation and leads to the development of atypical disease. Moreover, we present evidence that hedgehog signalling regulates the pathogenic profile of CD4 T cells by limiting their production of the inflammatory cytokines granulocyte-macrophage colony-stimulating factor and interferon-γ and by antagonizing their inflammatory program at the transcriptome level. Likewise, hedgehog signalling attenuates the inflammatory phenotype of human CD4 memory T cells. From a therapeutic point of view, our study underlines the potential of harnessing the hedgehog pathway to counteract ongoing excessive CNS inflammation, as systemic administration of a hedgehog agonist after disease onset effectively halts disease progression and significantly reduces neuroinflammation and the underlying neuropathology. We thus unveil a previously unrecognized role for the hedgehog pathway in regulating pathogenic inflammation within the CNS and propose to exploit its ability to modulate this neuroimmune network as a strategy to limit the progression of ongoing neuroinflammation.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Encefalomielite Autoimune Experimental/imunologia , Proteínas Hedgehog/imunologia , Inflamação/imunologia , Animais , Encéfalo/imunologia , Encéfalo/patologia , Linfócitos T CD4-Positivos/patologia , Encefalomielite Autoimune Experimental/metabolismo , Encefalomielite Autoimune Experimental/patologia , Proteínas Hedgehog/metabolismo , Humanos , Inflamação/metabolismo , Camundongos , Medula Espinal/imunologia , Medula Espinal/patologia
7.
Osteoarthritis Cartilage ; 29(10): 1389-1398, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34284112

RESUMO

Osteoarthritis (OA) is a major health problem worldwide that affects the joints and causes severe disability. It is characterized by pain and low-grade inflammation. However, the exact pathogenesis remains unknown and the therapeutic options are limited. In OA articular chondrocytes undergo a phenotypic transition becoming hypertrophic, which leads to cartilage damage, aggravating the disease. Therefore, a therapeutic agent inhibiting hypertrophy would be a promising disease-modifying drug. The therapeutic use of tyrosine kinase inhibitors has been mainly focused on oncology, but the Food and Drug Administration (FDA) approval of the Janus kinase inhibitor Tofacitinib in Rheumatoid Arthritis has broadened the applicability of these compounds to other diseases. Interestingly, tyrosine kinases have been associated with chondrocyte hypertrophy. In this review, we discuss the experimental evidence that implicates specific tyrosine kinases in signaling pathways promoting chondrocyte hypertrophy, highlighting their potential as therapeutic targets for OA.


Assuntos
Condrócitos/patologia , Osteoartrite/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Receptores com Domínio Discoidina/fisiologia , Receptores ErbB/fisiologia , Proteína-Tirosina Quinases de Adesão Focal/fisiologia , Humanos , Hipertrofia/tratamento farmacológico , Janus Quinase 2/fisiologia , Osteoartrite/fisiopatologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-fyn/fisiologia , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/fisiologia , Receptor IGF Tipo 1/fisiologia , Receptor trkA/fisiologia , Receptores de Fatores de Crescimento de Fibroblastos/fisiologia , Transdução de Sinais
8.
Med Vet Entomol ; 35(3): 478-483, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33340140

RESUMO

The study of intestinal microbiota in vector insects like triatomines is paramount in parasitology because many parasitic species inhabit the vector's gut. Although knowledge on the gut microbiota in various vectors of the parasitic flagellate Trypanosoma cruzi has grown, research efforts have focused on South American triatomines. This study reports the isolation of bacterial microbiota in the anterior and posterior gut of Meccus pallidipennis (a triatomine species endemic to Mexico) by culture, as well as its identification by phenotypic and biochemical tests and its quantification by counting colony-forming units. The study was performed on fifth-instar nymph and adult specimens of M. pallidipennis, either laboratory-bred or collected in the field and either infected or not with T. cruzi. Overall, 17 bacterial species were identified, with the genera Bacillus and Staphylococcus being the most prevalent regardless of the origin of the insects. No differences were observed in the number of bacterial species in the gut of laboratory-bred and field-collected insects, neither with respect to life stage or infection status. In general, the Shannon-Weaver diversity index was higher in non-infected insects than in infected ones. Further studies using non-culture methods are required to determine whether bacterial species diversity is modified by laboratory breeding.


Assuntos
Doença de Chagas , Reduviidae , Triatoma , Triatominae , Trypanosoma cruzi , Animais , Bactérias , Doença de Chagas/veterinária , Insetos Vetores , México
9.
Sensors (Basel) ; 22(1)2021 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-35009844

RESUMO

The use of gamification elements has extended from being a complement for a product to being integrated into multiple public services to motivate the user. The first drawback for service designers is choosing which gamification elements are appropriate for the intended audience, in addition to the possible incompatibilities between gamification elements. This work proposes a clustering technique that enables mapping different user profiles in relation to their preferred gamification elements. Additionally, by mapping the best cluster for each gamification element, it is possible to determine the preferred game genre. The article answered the following research questions: What is the relationship between the genre of the game and the element of gamification? Different user groups (profiles) for each gamification element? Results indicate that there are cases where the users are divided between those who agree or disagree. However, other elements present a great heterogeneity in the number of groups and the levels of agreement.


Assuntos
Gamificação , Cuidados Paliativos , Análise por Conglomerados , Humanos
10.
Eat Weight Disord ; 26(7): 2153-2163, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33159301

RESUMO

PURPOSE: The aim of this article was to validate the Spanish version of the Home Environment Survey (HES-S) and was divided in two studies: (1) to assess the reliability, convergent validity of HES-S in a survey of 145 parents of children with overweight/obesity; (2) to study the magnitude of the association between children's BMI status with the latent scores theoretically defined by the HES model. METHODS: To test the scale and the model, a confirmatory factor analysis (CFA) and a path analysis were carried out among a sample of 156 parents of preadolescents (106 overweight/obesity and 50 normal-weight children). No CFA or EFA were carried out in the validation of the original instrument. RESULTS: Study 1, both the Physical Activity and the Eating Habits components of the scale showed adequate levels of internal consistency for the majority of the scales, except for two. One of them, Healthy Eating Parental Policies (HEP) subscale was reduced after excluded two items, although it did not improve substantially. This model indicated that there was a significant association between the two Eating Habits scales and the child's weight status, but child's weight was not associated with the Physical Activity components. Convergent validity was confirmed by correlations with related variables: family eating habits (F-EAT), parent's physical activity (IPAQ), and children's physical activity (assessed via accelerometers during one week). Study 2, our results replicated the original four factor structure proposed for physical activity (CFI = 0.99; RMSEA = 0.03), but the original factor structure of the eating habits component was not supported. In addition, the relationship of the child's weight status, the Physical Activity components, and the two scales of Eating Habits (Parental Modeling and Policies) was explored with a path analysis showing good fit indices (CFI = 0.95; RMSEA = 0.06). Child's BMI was negatively associated with Healthy Eating Parental Role Modeling (r = - 0.21) and with Healthy Eating Parental Policies (r = - 0.19), but not with the factors of Child's Physical Activity model. CONCLUSION: To our knowledge, this is the first instrument to assess obesogenic family environment in Spanish speaking countries, which is a relevant dimension within a health perspective so as to implement new policies and strategies in obesity tertiary prevention. Overall, the confirmatory factor analysis of the HES-S has only provided additional support for one part related to Physical Activity. In addition, Child's BMI was correlated with scales of Eating Habits but not with Child's Physical Activity factor. These results clearly suggest that further research is warranted. LEVEL III: Case-control analytic study.


Assuntos
Obesidade , Sobrepeso , Índice de Massa Corporal , Criança , Comportamento Alimentar , Humanos , Pais , Reprodutibilidade dos Testes , Inquéritos e Questionários
11.
Eat Weight Disord ; 25(3): 751-759, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31077019

RESUMO

PURPOSE: The prevalence of childhood obesity continues to increase worldwide. The aims of this study were to (1) assess the psychological well-being and rates of teasing of Spanish children with obesity (OG) and compare them with their non-overweight peers (NG), and (2) analyze the mediating role of weight-related teasing on the relation between children's BMI z score and psychological well-being. METHODS: The cross-sectional study included 50 preadolescents with obesity, matched with non-overweight children according to age, sex, and socioeconomic status, who were assessed via self-report instruments measuring anxiety, depression, self-esteem, and teasing. RESULTS: The OG reported higher anxiety, depression, and teasing, and lower self-esteem. SEM revealed that children who scored worse on instruments assessing psychological well-being had higher BMI z scores. Weight-related teasing predicted poor psychological well-being scores and weight-related teasing mediated the relation between BMI and psychological well-being. CONCLUSIONS: The high rates of anxiety, depression, and weight-related teasing, as well as the low self-esteem, which was observed amongst the children with obesity, raise concerns about the quality of life of this population. Furthermore, the finding that weight-related teasing mediated the relationship between BMI and psychological well-being adds to a growing body of research, highlighting the harmful effects of weight-related stigma. Overall, these results highlight the importance of early intervention to assess for, and address, the presence of weight-related teasing and psychological well-being difficulties in preadolescents with obesity. LEVEL OF EVIDENCE: Level III, case-control study.


Assuntos
Obesidade Infantil/psicologia , Grupo Associado , Qualidade de Vida/psicologia , Autoimagem , Ansiedade/psicologia , Índice de Massa Corporal , Estudos de Casos e Controles , Criança , Estudos Transversais , Depressão/psicologia , Feminino , Humanos , Masculino , Espanha
12.
Aten Primaria ; 52(4): 240-249, 2020 04.
Artigo em Espanhol | MEDLINE | ID: mdl-30665707

RESUMO

OBJECTIVE: To analyze the nutritional status (NS) of patients older than 65 years and establish their relationship with sociodemographic and health variables. DESIGN: Cross-sectional observational study in patients older than 65 years. LOCATION: 3 health centers. PARTICIPANTS: 255 patients: ambulatory (AP), in domiciliary care (DP) or institutionalized (IP). They completed the study 243 (response rate 95.3%). MAIN MEASUREMENTS: The Chang method was applied to determine the NS. Sociodemographic, anthropometric variables, dependence, mood, cognitive and analytical parameters were collected. Associations were analyzed applying chi-square and analysis of variance. The prevalence ratio (PR) for malnutrition was calculated. A multivariate model was applied (binary logistic regression). Significance was considered for p<0.05. RESULTS: The average age was 81.3 years (SD=7.4) and 72.0% were women. 48.9% were AP, 26.8% DP and 24.2% IP. 29.6% (95% CI: 23.9-35.8) presented malnutrition. Greater malnutrition was established in relation to living in a residence or requiring home help (PR=5.3), age over 85 (PR=4.9), presenting a moderate or higher dependency for basic activities of daily living (PR=3.9) and instrumental (PR=3.3), need help for mobility (PR=2.9) and present moderate/severe cognitive impairment (PR=2.1). The determinants of malnutrition in the multivariate model were older than 85 years old and being IP or DP. CONCLUSIONS: Emphasis should be placed on evaluating NS in patients older than 85 years of age who live in a residence or require home care, since they are the groups at greatest risk of malnutrition.


Assuntos
Desnutrição/epidemiologia , Estado Nutricional , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Distribuição de Qui-Quadrado , Estudos Transversais , Feminino , Serviços de Assistência Domiciliar , Humanos , Pacientes Internados , Masculino , Desnutrição/etiologia , Pacientes Ambulatoriais , Prevalência , Distribuição por Sexo , Fatores Socioeconômicos , Espanha/epidemiologia
13.
Int J Mol Sci ; 20(2)2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-30669264

RESUMO

In the present work, we demonstrate the preparation of chitosan-based composites as vehicles of the natural occurring multi-drug resveratrol (RES). Such systems are endowed with potential therapeutic effects on inflammatory bowel diseases (IBD), such as Crohn's disease (CD) and ulcerative colitis, through the sustained colonic release of RES from long-lasting mucoadhesive drug depots. The loading of RES into nanoparticles (NPs) was optimized regarding two independent variables: RES/polymer ratio, and temperature. Twenty experiments were carried out and a Box⁻Behnken experimental design was used to evaluate the significance of these independent variables related to encapsulation efficiency (EE). The enhanced RES EE values were achieved in 24 h at 39 °C and at RES/polymer ratio of 0.75:1 w/w. Sizes and polydispersities of the optimized NPs were studied by dynamic light scattering (DLS). Chitosan (CTS) dispersions containing the RES-loaded NPs were ionically gelled with tricarballylic acid to yield CTS-NPs composites. Macro- and microscopic features (morphology and porosity studied by SEM and spreadability), thermal stability (studied by TGA), and release kinetics of the RES-loaded CTS-NPs were investigated. Release patterns in simulated colon conditions for 48 h displayed significant differences between the NPs (final cumulative drug release: 79⁻81%), and the CTS-NPs composites (29⁻34%).


Assuntos
Materiais Biocompatíveis/química , Quitosana/química , Colo/efeitos dos fármacos , Portadores de Fármacos/química , Nanopartículas/química , Resveratrol/administração & dosagem , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacocinética , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Hidrogéis/química , Nanopartículas/ultraestrutura , Especificidade de Órgãos/efeitos dos fármacos , Polímeros/química , Resveratrol/farmacocinética , Temperatura , Termodinâmica , Termogravimetria
14.
Phys Chem Chem Phys ; 20(41): 26570-26579, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30306971

RESUMO

Carbon capture and storage using regenerable sorbents are an effective approach to reduce CO2 emissions from stationary sources. In this work, lithium orthosilicate (Li4SiO4) was studied as a carbon dioxide sorbent. For a deeper understanding of the synthesis and carbonation mechanism of Li4SiO4, an in situ synchrotron radiation powder X-ray diffraction technique was used. The Li4SiO4 powders were synthesized by a combination of ball milling of a Li2CO3 and SiO2 mixture followed by a thermal treatment process at low temperature. In situ studies showed that formation of Li4SiO4 from the as-milled 2Li2CO3-SiO2 mixture involves decomposition of Li2CO3 by reaction with SiO2via Li2SiO3 as an intermediate compound. No evidence of Li2Si2O5 formation was obtained, in spite of thermodynamic predictions. The CO2 capture by Li4SiO4 was evaluated dynamically over a wide temperature range, reaching a maximum weight increase of 34 wt% and good cyclability after about 10 cycles. By thermogravimetric and microstructural analyses in combination with ex situ and in situ measurements, a two step carbonation mechanism and its influence on the final CO2 capture was clearly elucidated. Under dynamical conditions up to 700 °C, the lower number of Li2CO3 nuclei initially formed retards the double shell formation and the nucleation and growth of the Li2CO3 particles remains the controlling step up to higher CO2 capture capacity. Isothermal carbonation at 700 °C favours the formation of a higher number of Li2CO3 nuclei that creates a thin carbonate shell. The CO2 diffusion through this shell is the limiting step from the beginning and further carbonation is hindered as the reaction progresses.

15.
Stud Mycol ; 90: 71-118, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29276320

RESUMO

Fresh collections, type studies and molecular phylogenetic analyses of a multigene matrix of partial nuSSU-ITS-LSU rDNA, rpb2, tef1 and tub2 sequences were used to evaluate the boundaries of Cucurbitaria in a strict sense and of several related genera of the Cucurbitariaceae. Two species are recognised in Cucurbitaria and 19 in Neocucurbitaria. The monotypic genera Astragalicola, Cucitella, Parafenestella, Protofenestella, and Seltsamia are described as new. Fenestella is here included as its generic type F. fenestrata (= F. princeps), which is lecto- and epitypified. Fenestella mackenzei and F. ostryae are combined in Parafenestella. Asexual morphs of Cucurbitariaceae, where known, are all pyrenochaeta- or phoma-like. Comparison of the phylogenetic analyses of the ITS-LSU and combined matrices demonstrate that at least rpb2 sequences should be added whenever possible to improve phylogenetic resolution of the tree backbone; in addition, the tef1 introns should be added as well to improve delimitation of closely related species.

16.
Environ Geochem Health ; 40(5): 1803-1815, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28342154

RESUMO

This study aims to determine aluminum fractions in the fine earth of acidic soils under different land uses (forest, pasture and cultivation) and in the river bed sediments of the headwater of the Mero River in order to identify and quantify Al-bearing phases to assess Al mobility and potential bioavailability (environmental availability) in the monitoring area. Sequential extraction is used to evaluate the Al partitioning into six fractions operationally defined: soluble/exchangeable/specifically adsorbed, bound to manganese oxides, associated with amorphous compounds, aluminum bound to oxidizable organic matter, associated with crystalline iron oxides, and residual fraction (aluminum within the crystal lattices of minerals). The mean concentration of total aluminum (24.01 g kg-1) was similar for the three considered uses. The mean percentage of the aluminum fractions, both in soils and sediments, showed the following order: residual fraction â‰« amorphous compounds ≈ crystalline iron oxides > water-soluble/exchangeable/specifically adsorbed > bound to oxidizable organic matter ≈ Mn oxides. However, in the soils, the amorphous compounds and water-soluble/exchangeable/specifically adsorbed fraction showed considerable differences between some types of uses, the percentage of aluminum linked to amorphous compounds being higher in forest soils (16% of total Al) compared to other uses (mean about 8% of total Al). The highest values of water-soluble/exchangeable/specifically adsorbed Al were also found in forest soils (mean 8.6% of the total Al versus about 4% of pasture and cultivation), which is consistent with the lower pH and higher organic matter content in forest soils. Nevertheless, the potentially bioavailable fraction (sum of the first three fractions) is low, suggesting very low geoavailability of this element in both soils and sediments; hence, the possibility to affect the crops and water quality is minimal.


Assuntos
Alumínio/análise , Fracionamento Químico/métodos , Sedimentos Geológicos/química , Rios/química , Poluentes do Solo/análise , Poluentes do Solo/química , Disponibilidade Biológica , Monitoramento Ambiental/métodos , Minerais/análise , Espanha , Poluentes Químicos da Água/química , Qualidade da Água
17.
J Food Sci Technol ; 55(11): 4477-4484, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30333644

RESUMO

The progressive elimination of fish discards established by the European Union Council in 2013 has stimulated the valorization of flesh from discarded high-quality species with good protein functional properties but which frequently have excessive fish-bones, fat, strange flavours, soft texture, etc. The present study therefore focuses on valorization of the extracted muscle (minced muscle), from several fish species frequently discarded in north-western Spanish fisheries (Atlantic Ocean): Blue whiting (Micromesistius poutassou), Mackerel (Scomber scombrus), Red scorpionfish (Scorpaena scrofa), Pouting (Trisoreptus luscus) and Gurnard (Trigla spp.). Valorization of these discarded fish resources is a key objective for the survival of the fishery sector in this area. In this regard present study was planned to examine the behaviour of the mince during 6 months of frozen storage by means of physicochemical and sensory analyses, and to test consumer acceptance of three technologically different products (burgers, nuggets and structured fingers) prepared with fish mince from different species. Results indicated that protein aggregation started at the outset of frozen storage but progressed very slowly, with the exception of non-washed blue whiting and red scorpionfish minces. Moreover, during frozen storage lipid oxidation increased in all samples; the increase was with two objectives highest in minced mackerel, a fatty fish, but no rancid flavour was detected. All mince samples presented acceptable physicochemical properties and good sensory acceptability after 6 months of frozen storage. Acceptability of final products made with these minces was high in all cases. Burgers were more acceptable for consumers aged over 40 and fingers and nuggets more for younger people.

18.
Opt Express ; 25(12): 13372-13381, 2017 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-28788874

RESUMO

We present the isolation of single attosecond pulses for multi-cycle and few-cycle laser pulses from high harmonic generation in overdense plasmas, calculated with particle-in-cell simulations. By the combination of two laser pulses of equal amplitude and a small frequency shift between them, we demonstrate that it is possible to shorten the region in which the laser pulse is most intense, therefore restricting the generation of high harmonic orders in the form of attosecond pulses to a narrower time window. The creation of this window is achieved due to the combination of the laser pulse envelope and the slow oscillating wave obtained from the coherent sum of the two pulses. A parametric scan, performed with particle-in-cell simulations, reveals how the pulse isolation behaves for different input laser pulse lengths and which are the optimal frequency shifts between the two laser pulses in each case, giving the conditions for having a good isolation of an attosecond pulse when working with laser-plasma interaction in overdense targets.

19.
Opt Express ; 25(13): 14974-14985, 2017 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-28788933

RESUMO

Plasmon resonances are known to amplify the electromagnetic fields near metallic nanostructures, providing a promising scheme to generate extreme-ultraviolet harmonics using low power drivings. During high-order harmonic generation (HHG), the driving and harmonic fields accumulate a phase difference as they propagate through the target. In a typical set-up -a laser focused into a gas jet- the propagation distances amount to several wavelengths, and the cumulative phase-mismatch affects strongly the efficiency and properties of the harmonic emission. In contrast, HHG in metallic nanostructures is considered to overcome these limitations, as the common sources of phase mismatch -optical density and focusing geometry- are negligible for subwavelength propagation distances. We demonstrate that phase matching still plays a relevant role in HHG from nanostructures due to the non-perturbative character of HHG, that links the harmonic phase to the intensity distribution of the driving field. Our computations show that widely used applications of phase matching control, such as quantum path selection and the increase of contrast in attosecond pulse generation, are also feasible at the nanoscale.

20.
Oncology ; 92(2): 68-74, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27855387

RESUMO

OBJECTIVE: To analyse the evolution of a multidisciplinary heredofamilial cancer unit (HFCU) in a university hospital. METHODS: This was a retrospective analysis of the activity of our HFCU in its first 5 years of existence. RESULTS: Between July 2010 and July 2015, 1,518 patients from 1,318 families attended our HFCU. Genetic testing was offered to 862 patients. Of those, 833 (96.6%) accepted testing, with available results for 636 (76.4%). Pathogenic mutations in BRCA1 and BRCA2 were found in 175 patients. Lynch syndrome and adenomatous polyposis were the most frequent syndromes diagnosed (151/175, 86.3%) among 17 different syndromes studied. Of the 404 patients without a previous genetic diagnosis in the family, 62 (15.3%) were found to have mutations in disease-causing genes. Prophylactic surgery and follow-up (33.7%) or follow-up only (66.3%) was proposed for mutation carriers according to international guidelines and patients' preferences. CONCLUSION: We have a high mutation detection rate, genetic test acceptance, and compliance with risk reduction strategies. However, there is room for improvement, especially in genetic testing timing, considering that an increase in the indications for genetic testing is expected.


Assuntos
Hospitais Universitários/organização & administração , Síndromes Neoplásicas Hereditárias/terapia , Feminino , Predisposição Genética para Doença , Testes Genéticos , Humanos , Masculino , Síndromes Neoplásicas Hereditárias/classificação , Síndromes Neoplásicas Hereditárias/genética , Estudos Retrospectivos , Espanha
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