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1.
Photochem Photobiol Sci ; 23(5): 941-955, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38643418

RESUMO

The identification of more efficient, clean, secure, and competitive energy supply is necessary to align with the needs of sustainable devices. For this reason, a study for developing innovative dye-sensitized solar cells (DSSCs) based on microbial pigments is reported starting from Talaromyces atroroseus GH2. The fungus was cultivated by fermentation and the extracellular pigment extract was characterized by HPLC-DAD-ESI-MS analyses. The most abundant compound among the 22 azaphilone-type pigments identified was represented by PP-O. The device's behavior was investigated in relation to electrolyte and pH for verifying the stability on time and the photovoltaic performance. Devices obtained were characterized by UV-vis measurements to verify the absorbance intensity and transmittance percentage. Moreover, photovoltaic parameters through photo-electrochemical measurements (I-V curves) and impedance characteristics by Electrochemical Impedance Spectroscopy (EIS) were determined. The best microbial device showed a short-circuit current density (Jsc) of 0.69 mA/cm2, an open-circuit photo-voltage (Voc) of 0.27 V and a Fill Factor (FF) of 0.60. Furthermore, the power conversion efficiency (PCE) of the device was 0.11%. Thus, the present study demonstrated the potential of microbial origin pigments for developing DSSCs.


Assuntos
Corantes , Energia Solar , Talaromyces , Talaromyces/química , Talaromyces/metabolismo , Corantes/química , Pigmentos Biológicos/química
2.
BMC Public Health ; 24(1): 2383, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223469

RESUMO

OBJECTIVE: Evidence from low- and middle-income countries regarding the effect of smoking in people with diabetes is lacking. Here, we report the association of smoking with mortality in a large cohort of Mexican adults with diabetes. METHODS: Participants with diabetes mellitus (self-reported diagnosis, use of antidiabetic medications or HbA1c ≥ 6.5%) aged 35-74 years when recruited into the Mexico City Prospective Study were included. Cox regression confounder-adjusted mortality rate ratios (RRs) associated with baseline smoking status were estimated. RESULTS: Among 15,975 women and 8225 men aged 35-74 years with diabetes but no other comorbidities at recruitment, 2498 (16%) women and 2875 (35%) men reported former smoking and 2753 (17%) women, and 3796 (46%) men reported current smoking. During a median of 17 years of follow-up there were 5087 deaths at ages 35-74 years. Compared with never smoking, all-cause mortality RR was 1.08 (95%CI 1.01-1.17) for former smoking, 1.11 (95%CI 1.03-1.20) for current smoking, 1.09 (95%CI 0.99-1.20) for non-daily smoking, 1.06 (95%CI 0.96-1.16) for smoking < 10 cigarettes/day (median during follow-up 4 cigarettes/day), and 1.28 (95% CI 1.14-1.43) for smoking ≥ 10 cigarettes/day (median during follow-up 15 cigarettes/day). Mortality risk among daily smokers was greatest for COPD, lung cancer, cardiovascular diseases, and acute diabetic complications. CONCLUSION: In this cohort of Mexican adults with diabetes, low-intensity daily smoking was associated with increased mortality, despite observing smoking patterns which are different from other populations, and over 5% of total deaths were associated with smoking.


Assuntos
Causas de Morte , Diabetes Mellitus , Fumar , Humanos , Pessoa de Meia-Idade , Masculino , Feminino , México/epidemiologia , Adulto , Estudos Prospectivos , Idoso , Fumar/epidemiologia , Diabetes Mellitus/mortalidade , Diabetes Mellitus/epidemiologia , Fatores de Risco
3.
Phys Chem Chem Phys ; 25(13): 9656-9668, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36943209

RESUMO

DFT calculations were performed to study the effect on energetic and magnetic stability when clusters with up to 24 lithium atoms were doped with one and two atoms of yttrium. In this, the effect of the charge was considered. As a result, some stable structures were identified as possible magnetic superatoms, among them, the YLi12+ cluster with an icosahedron geometry with a spin magnetic moment of 4 bohr magnetons. The participation of yttrium in the electron density of the unpaired electrons providing magnetism in clusters was corroborated at the level of a density of states (DOS) calculation and a spin density calculation. In particular, in the Y2Li12+ superatom, it was found that the encapsulated yttrium atom participates with 35.02% and the second yttrium atom with 15.04%. These percentages, with a contribution from p orbitals, but to a greater extent by d orbitals. The complementation to these percentages is due to the participation of the s and p orbitals of the lithium atoms. In general, doping with a second yttrium atom allowed to obtain a greater amount of high magnetic moments, and considering charged clusters allowed to obtain also high magnetic moments.

4.
J Anim Breed Genet ; 140(1): 39-48, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36286321

RESUMO

Inbreeding depression in closed populations impairs animal fitness, health, and productivity. However, not all inbreeding is expected to be equally damaging. Recent inbreeding is thought to be more harmful than ancient inbreeding because selection decreases the frequency of unfavourable alleles with time. Accordingly, selection efficiency is improved by inbreeding in a process called purging. This research aimed to quantify inbreeding depression on growth and prolificacy traits in two lines of rabbits selected for just one growth (Caldes line) or prolificacy (Prat line) trait, and also to find some evidence of purging of deleterious alleles by selection. Caldes line comprised 51 generations and 124,371 animals in the pedigree. Prat line comprised 34 generations and 161,039 animals in the pedigree. The effects of old, intermediate, and new inbreeding (Fold, Fint, and Fnew), as well as total cumulated classical inbreeding (F) and 3 measurements of ancestral inbreeding (AHC, Fa.K, and Fa.B) were estimated for average daily gain (ADG), slaughter weight (SW), weaning weight (WW), born alive (BA), the total number of kits (NT), and the number of weaned kits (NW). There was a clear inbreeding depression for all growth and prolificacy traits in the Caldes line (-7.19 g/d, -0.45 kg, -0.25 kg, -6 kits, -4 kits, and -4 kits per unit of increase in F for ADG, SW, WW, BA, NT, and NW, respectively) and also in Prat line (-7.48 g/d, -0.31 kg, -0.11 kg, -4 kits, -5 kits, and -4 kits per unit of increase in F for ADG, SW, WW, BA, NT, and NW, respectively). The inbreeding partition appears to be a reliable alternative for assessing inbreeding depression and purging. Thus, for example, in the Caldes line and for ADG the regression coefficients were -7.61, -5.41, and 7.76 g/d per unit of increase in Fnew, Fint, and Fold, respectively. In addition, AHC and Fa.B may provide more accurate evidence of purging than Fa.K. This study confirms the existence of inbreeding depression for growth and prolificacy traits in both lines of rabbits and shows evidence of purging of deleterious recessive alleles involved both in growth and prolificacy, independently of the selection criteria established in the line.


Assuntos
Animais , Coelhos
5.
Genet Sel Evol ; 54(1): 81, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36536288

RESUMO

BACKGROUND: The effect of the cecal microbiome on growth of rabbits that were fed under different regimes has been studied previously. However, the term "effect" carries a causal meaning that can be confounded because of potential genetic associations between the microbiome and production traits. Structural equation models (SEM) can help disentangle such a complex interplay by decomposing the effect on a production trait into direct host genetics effects and indirect host genetic effects that are exerted through microbiota effects. These indirect effects can be estimated via structural coefficients that measure the effect of the microbiota on growth while the effects of the host genetics are kept constant. In this study, we applied the SEM approach to infer causal relationships between the cecal microbiota and growth of rabbits fed under ad libitum (ADGAL) or restricted feeding (ADGR). RESULTS: We identified structural coefficients that are statistically different from 0 for 138 of the 946 operational taxonomic units (OTU) analyzed. However, only 15 and 38 of these 138 OTU had an effect greater than 0.2 phenotypic standard deviations (SD) on ADGAL and ADGR, respectively. Many of these OTU had a negative effect on both traits. The largest effects on ADGR were exerted by an OTU that is taxonomically assigned to the Desulfovibrio genus (- 1.929 g/d, CSS-normalized OTU units) and by an OTU that belongs to the Ruminococcaceae family (1.859 g/d, CSS-normalized OTU units). For ADGAL, the largest effect was from OTU that belong to the S24-7 family (- 1.907 g/d, CSS-normalized OTU units). In general, OTU that had a substantial effect had low to moderate estimates of heritability. CONCLUSIONS: Disentangling how direct and indirect effects act on production traits is relevant to fully describe the processes of mediation but also to understand how these traits change before considering the application of an external intervention aimed at changing a given microbial composition by blocking/promoting the presence of a particular microorganism.


Assuntos
Microbiota , Animais , Coelhos , Ceco , RNA Ribossômico 16S/genética
6.
Genet Sel Evol ; 54(1): 46, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35761200

RESUMO

BACKGROUND: The rabbit cecum hosts and interacts with a complex microbial ecosystem that contributes to the variation of traits of economic interest. Although the influence of host genetics on microbial diversity and specific microbial taxa has been studied in several species (e.g., humans, pigs, or cattle), it has not been investigated in rabbits. Using a Bayes factor approach, the aim of this study was to dissect the effects of host genetics, litter and cage on 984 microbial traits that are representative of the rabbit microbiota. RESULTS: Analysis of 16S rDNA sequences of cecal microbiota from 425 rabbits resulted in the relative abundances of 29 genera, 951 operational taxonomic units (OTU), and four microbial alpha-diversity indices. Each of these microbial traits was adjusted with mixed linear and zero-inflated Poisson (ZIP) models, which all included additive genetic, litter and cage effects, and body weight at weaning and batch as systematic factors. The marginal posterior distributions of the model parameters were estimated using MCMC Bayesian procedures. The deviance information criterion (DIC) was used for model comparison regarding the statistical distribution of the data (normal or ZIP), and the Bayes factor was computed as a measure of the strength of evidence in favor of the host genetics, litter, and cage effects on microbial traits. According to DIC, all microbial traits were better adjusted with the linear model except for the OTU present in less than 10% of the animals, and for 25 of the 43 OTU with a frequency between 10 and 25%. On a global scale, the Bayes factor revealed substantial evidence in favor of the genetic control of the number of observed OTU and Shannon indices. At the taxon-specific level, significant proportions of the OTU and relative abundances of genera were influenced by additive genetic, litter, and cage effects. Several members of the genera Bacteroides and Parabacteroides were strongly influenced by the host genetics and nursing environment, whereas the family S24-7 and the genus Ruminococcus were strongly influenced by cage effects. CONCLUSIONS: This study demonstrates that host genetics shapes the overall rabbit cecal microbial diversity and that a significant proportion of the taxa is influenced either by host genetics or environmental factors, such as litter and/or cage.


Assuntos
Microbiota , Animais , Teorema de Bayes , Bovinos , Ceco , Microbiota/genética , RNA Ribossômico 16S/genética , Coelhos , Suínos , Desmame
7.
Genet Sel Evol ; 54(1): 53, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35883024

RESUMO

BACKGROUND: Feed efficiency during lactation involves a set of phenotypic traits that form a complex system, with some traits exerting causal effects on the others. Information regarding such interrelationships can be used to predict the effect of external interventions on the system, and ultimately to optimize management practices and multi-trait selection strategies. Structural equation models can be used to infer the magnitude of the different causes of such interrelationships. The causal network necessary to fit structural equation models can be inferred using the inductive causation (IC) algorithm. By implementing these statistical tools, we inferred the causal association between the main energy sources and sinks involved in sow lactation feed efficiency for the first time, i.e., daily lactation feed intake (dLFI) in kg/day, daily sow weight balance (dSWB) in kg/day, daily litter weight gain (dLWG) in kg/day, daily back fat thickness balance (dBFTB) in mm/day, and sow metabolic body weight (SMBW) in kg0.75. Then, we tested several selection strategies based on selection indices, with or without dLFI records, to improve sow efficiency during lactation. RESULTS: The IC algorithm using 95% highest posterior density (HPD95%) intervals resulted in a fully directed acyclic graph, in which dLFI and dLWG affected dSWB, the posterior mean of the corresponding structural coefficients (PMλ) being 0.12 and - 0.03, respectively. In turn, dSWB influenced dBFTB and SMBW, with PMλ equal to 0.70 and - 1.22, respectively. Multiple indirect effects contributed to the variances and covariances among the analyzed traits, with the most relevant indirect effects being those involved in the association between dSWB and dBFTB and between dSWB and SMBW. Selection strategies with or without phenotypic information on dLFI, or that hold this trait constant, led to the same pattern and similar responses in dLFI, dSWB, and dLWG. CONCLUSIONS: Selection based on an index including only dBFTB and dLWG records can reduce dLFI, keep dSWB constant or increase it, and increase dLWG. However, a favorable response for all three traits is probably not achievable. Holding the amount of feed provided to the sows constant did not offer an advantage in terms of response over the other strategies.


Assuntos
Ingestão de Alimentos , Lactação , Ração Animal/análise , Animais , Feminino , Tamanho da Ninhada de Vivíparos , Fenótipo , Gravidez , Suínos/genética , Aumento de Peso
8.
J Anim Breed Genet ; 139(5): 530-539, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35557470

RESUMO

The interaction between the genotype and feeding regimen (G×FR) for slaughter traits was estimated from data corresponding to 2557 animals under full (FF) and 2424 with restricted feeding (RF). Expected responses to selection under different scenario regarding feeding regimen were also calculated. Body weight at slaughter (SW), carcass weight (CW) and dressing out percentage (DoP) were analysed by using linear animal models in which records obtained under different feeding regimes were treated as different traits. Animals belonged to Caldes line, selected for average daily gain (G) under ad libitum feeding. The selection process information was included in the analyses. Marginal posterior mean of heritabilities were 0.102 for G, and 0.364, 0.257 and 0.167 for SW, CW and DoP under FF feeding. The corresponding values for animals fed on RF were 0.243, 0.203 and 0.379 for SW, CW and DoP, respectively. Genetic correlations between G and CW were positive and moderate, and those between G and DoP were low. The estimated genetic correlation between SW, CW and DoP under different feeding regimens were: 0.73, 0.69 and 0.87, respectively. These correlations cannot be said to be far enough from one to generate relevant G×FR interaction variance, which were estimated to be only 11.1%, 8.6% and 5.3% of the mean of the phenotypic variance for SW, CW and DoP, respectively. This lack of G×FR interaction variance, jointly with the higher heritability of DoP under RF, explains that the genetic improvement of DoP can be done more efficiently recording traits on animals under RF, even if the interest is on the performances under FF, i.e. by indirect selection.


Assuntos
Composição Corporal , Animais , Composição Corporal/genética , Peso Corporal , Genótipo , Fenótipo , Coelhos
9.
J Anim Breed Genet ; 138(4): 508-517, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33682252

RESUMO

The enhancement of rabbit female functional longevity, that is the ability to avoid voluntary culling, is a paramount aspect for the sustainability of meat rabbit production; this trait represents a direct indicator of female robustness. The objective of our study was to compare the functional longevity of five rabbit lines at their foundation and at fixed times during their selection processes. Four of them are maternal lines (A, V, H and LP) selected for litter size at weaning. The fifth line is the paternal line R, founded and selected for post-weaning daily gain from 28 to 63 days. The comparison at foundation involved the complete data set (from March 1980 to March 2013; records of 15,670 does) and pedigree (19,405 animals). Latter comparisons were made when all lines shared the same environmental and management conditions, from March 1997 to September 1998 and from March 2011 to September 2012. In these second comparisons, the same model as that used in the comparison at foundation was used, but now the additive effect was excluded, only data from the corresponding periods were considered. At their foundation, lines V, H and LP showed larger functional longevity than lines A and R, being LP line that with the longest productive life. In the latter comparisons, lines A and R still showing the lowest functional longevities. However, as the selection process evolves, the differences between these two lines and the others were reduced. It could be concluded that the average longevity of a population greatly depends on the criteria followed for its foundation. In addition, along the selection for litter size, the differences of longevity between lines tend to decrease, this is due to an unintended selection for functional longevity, since only offspring from females reaching three parturitions are selected as breeding animals for the next generation.


Assuntos
Longevidade , Animais , Feminino , Tamanho da Ninhada de Vivíparos , Fenótipo , Gravidez , Coelhos , Seleção Genética , Desmame
10.
Eur J Dent Educ ; 25(4): 856-863, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33471391

RESUMO

INTRODUCTION: Digital workflow is currently available for different fields of dentistry. Additionally, to clinical use, digital technology is focused on the education and training of students. The objective of this study was to show the potential benefit of the use of digital CAD / CAM technology and assisted training software in the evaluation and improvement of student skills in preclinical and clinical environments. MATERIALS AND METHODS: 30 models of dental preparations were digitalised and analysed by PrepCheck software, after that was used the PrepCheck Report tool, gathering the results of the analysis in an automatically created report and containing the following parameters: analysis of the conicity, distance between a preparation and the opposing jaw, analysis of the type of preparation, quality of the margin and total occlusal convergence. RESULTS: The use of the PrepCheck Pro 2.1 software makes evident the errors made by the students during the biomechanical preparation, since they generally change the inclination, in order to have less difficulties to comply with the parameters established in the preparations. Regarding the evaluated parameters for anterior and posterior fixed prosthesis) such as: 'Conicity', 'Type of preparation' and 'Distance to the antagonist', the preparations, in their majority, were classified within the tolerance range with of 50-60%, 80-93% and 53-67%, respectively. CONCLUSION: This pilot study demonstrated the benefits of using software and CAD/CAM technology in both preclinical and clinical environments for teaching and learning. Its use on preclinical environments allows the student observe qualitatively and quantitatively a preparation flaws when compared to a master's preparation. Lastly, the ease of visualising errors associated with magnification would allow students to improve their skills.


Assuntos
Competência Clínica , Educação em Odontologia , Avaliação Educacional , Humanos , Projetos Piloto , Software
11.
Genet Sel Evol ; 52(1): 53, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32993480

RESUMO

BACKGROUND: Traits recorded on animals that are raised in groups can be analysed with the social effects animal model (SAM). For multiple traits, this model specifies the genetic correlation structure more completely than the animal model (AM). Our hypothesis was that by using the SAM for genetic evaluation of average daily gain (ADG) and backfat thickness (BF), a high rate of improvement in feed conversion ratio (FCR) might be achieved, since unfavourable genetic correlations between ADG and BF reported in a Duroc pig line could be partially avoided. We estimated genetic and non-genetic correlations between BF, ADG and FCR on 1144 pigs using Bayesian methods considering the SAM; and responses to selection indexes that combine estimates of indirect (IGE) and direct (DGE) genetic effects for ADG and BF by stochastic simulation. RESULTS: Estimates of the ratio of the variance of DGE to the phenotypic variance were 0.31, 0.39 and 0.25 and those of the total genetic variance to the phenotypic variance were 0.63, 0.74 and 0.93 for ADG, BF and FCR, respectively. In spite of this, when the SAM was used to generate data and for the genetic evaluations, the average economic response was worse than that obtained when BV predictions from the AM were considered. The achieved economic response was due to a direct reduction in BF and not to an improvement in FCR. CONCLUSIONS: Our results show that although social genetic effects play an important role in the traits studied, their proper consideration in pig breeding programs to improve FCR indirectly is still difficult. The correlations between IGE and DGE that could help to overcome the unfavourable genetic correlations between DGE did not reach sufficiently high magnitudes; also, the genetic parameters estimates from the SAM have large errors. These two factors penalize the average response under the SAM compared to the AM.


Assuntos
Ração Animal , Modelos Genéticos , Seleção Artificial , Suínos/genética , Aumento de Peso , Adiposidade , Fenômenos Fisiológicos da Nutrição Animal , Animais , Variação Biológica da População , Carne de Porco/normas , Característica Quantitativa Herdável , Suínos/fisiologia
12.
Psychiatr Q ; 91(1): 183-190, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31811580

RESUMO

To evaluate the level of adherence to antidepressant therapies and associated factors in patients with depressive disorders. a cross-sectional analytical study was conducted in patients diagnosed with depressive disorders. The sample was for convenience, and a survey including sociodemographic, clinical, and therapeutic variables was designed. The Morisky-Green test, Beliefs about Medicines Questionnaire, and Simplified Medication Adherence Questionnaire were also used, all of which have been validated for assessing adherence in patients with depression. The qualitative variables were evaluated with absolute and relative frequencies, and a bivariate analysis was performed. This study included 54 patients with an average age of 49.5 ± 13.7 years, and 83.3% were women. All patients were diagnosed with major depression, and 9.25% also had an anxiety disorder. According to the Morisky-Green test, only 37% of patients were compliant with the drug therapy, although this was not statistically significant. Women were less compliant than men (33.3% versus 55.6%; p = 0.21). The beliefs that patients have regarding medication do not have a great impact on adherence to antidepressant therapy. However, it was evidenced that adherent patients had less doubts about the medication administered in comparison to non-adherent patients.


Assuntos
Antidepressivos/administração & dosagem , Transtorno Depressivo Maior/tratamento farmacológico , Conhecimentos, Atitudes e Prática em Saúde , Adesão à Medicação/estatística & dados numéricos , Adulto , Transtornos de Ansiedade/epidemiologia , Colômbia/epidemiologia , Comorbidade , Estudos Transversais , Transtorno Depressivo Maior/epidemiologia , Feminino , Hospitais Psiquiátricos/estatística & dados numéricos , Hospitais Públicos/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Ambulatório Hospitalar/estatística & dados numéricos , Fatores Sexuais
13.
Genet Sel Evol ; 51(1): 27, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31195962

RESUMO

BACKGROUND: Selection of mice for decreased environmental variability of birth weight has achieved higher survivability and larger litter size as a correlated response to canalized selection, which suggests higher welfare and robustness, and animals that are more homogeneous. However, in these studies, animals were not exposed to an environmental challenge. To demonstrate the advantages of this mouse line with a low environmental variability of birth weight, animals from two divergent lines (high and low variability of birth weight) were subjected to feed restriction. The objective of this study was to use these divergent lines to compare their response in terms of robustness against an environmental challenge. At weaning, 120 females, i.e. four full-sib females from 10 random litters of three consecutive generations of selection, were chosen from these divergent lines. The total number of females was divided into four groups, which were subjected to a feeding regimen by imposing different levels of feed restriction (i.e. 75, 90 and 85% of full ad libitum feed across three generations, respectively) in different combinations during the growth and reproduction periods. RESULTS: Animals from the "low" line were less sensitive to a change in feed level than those from the "high" line. Regarding reproduction, the "low" line performed better in terms of number of females having parturitions, number of parturitions, and litter size. Imposing a feed restriction on female mice during their growth period did not affect the birth weight of their pups. The "low" line was preferred because of its higher reproductive efficiency and survival under an environmental challenge. CONCLUSIONS: Selection for decreased environmental variability of birth weight produces animals that are less sensitive to environmental conditions, which can be interpreted as having greater robustness.


Assuntos
Variação Biológica da População , Peso ao Nascer , Restrição Calórica , Seleção Genética , Animais , Meio Ambiente , Feminino , Especiação Genética , Masculino , Camundongos , Seleção Artificial
14.
Genet Sel Evol ; 51(1): 10, 2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30866799

RESUMO

BACKGROUND: To date, the molecular mechanisms that underlie residual feed intake (RFI) in pigs are unknown. Results from different genome-wide association studies and gene expression analyses are not always consistent. The aim of this research was to use machine learning to identify genes associated with feed efficiency (FE) using transcriptomic (RNA-Seq) data from pigs that are phenotypically extreme for RFI. METHODS: RFI was computed by considering within-sex regression on mean metabolic body weight, average daily gain, and average backfat gain. RNA-Seq analyses were performed on liver and duodenum tissue from 32 high and 33 low RFI pigs collected at 153 d of age. Machine-learning algorithms were used to predict RFI class based on gene expression levels in liver and duodenum after adjusting for batch effects. Genes were ranked according to their contribution to the classification using the permutation accuracy importance score in an unbiased random forest (RF) algorithm based on conditional inference. Support vector machine, RF, elastic net (ENET) and nearest shrunken centroid algorithms were tested using different subsets of the top rank genes. Nested resampling for hyperparameter tuning was implemented with tenfold cross-validation in the outer and inner loops. RESULTS: The best classification was obtained with ENET using the expression of 200 genes in liver [area under the receiver operating characteristic curve (AUROC): 0.85; accuracy: 0.78] and 100 genes in duodenum (AUROC: 0.76; accuracy: 0.69). Canonical pathways and candidate genes that were previously reported as associated with FE in several species were identified. The most remarkable pathways and genes identified were NRF2-mediated oxidative stress response and aldosterone signalling in epithelial cells, the DNAJC6, DNAJC1, MAPK8, PRKD3 genes in duodenum, and melatonin degradation II, PPARα/RXRα activation, and GPCR-mediated nutrient sensing in enteroendocrine cells and SMOX, IL4I1, PRKAR2B, CLOCK and CCK genes in liver. CONCLUSIONS: ML algorithms and RNA-Seq expression data were found to provide good performance for classifying pigs into high or low RFI groups. Classification was better with gene expression data from liver than from duodenum. Genes associated with FE in liver and duodenum tissue that can be used as predictive biomarkers for this trait were identified.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal/genética , Perfilação da Expressão Gênica/métodos , Aprendizado de Máquina , Suínos/genética , Transcriptoma , Ração Animal , Animais , Cruzamento/métodos , Suínos/fisiologia
15.
Genet Sel Evol ; 51(1): 48, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477014

RESUMO

BACKGROUND: Feed efficiency (FE) has a major impact on the economic sustainability of pig production. We used a systems-based approach that integrates single nucleotide polymorphism (SNP) co-association and gene-expression data to identify candidate genes, biological pathways, and potential predictors of FE in a Duroc pig population. RESULTS: We applied an association weight matrix (AWM) approach to analyse the results from genome-wide association studies (GWAS) for nine FE associated and production traits using 31K SNPs by defining residual feed intake (RFI) as the target phenotype. The resulting co-association network was formed by 829 SNPs. Additive effects of this SNP panel explained 61% of the phenotypic variance of RFI, and the resulting phenotype prediction accuracy estimated by cross-validation was 0.65 (vs. 0.20 using pedigree-based best linear unbiased prediction and 0.12 using the 31K SNPs). Sixty-eight transcription factor (TF) genes were identified in the co-association network; based on the lossless approach, the putative main regulators were COPS5, GTF2H5, RUNX1, HDAC4, ESR1, USP16, SMARCA2 and GTF2F2. Furthermore, gene expression data of the gluteus medius muscle was explored through differential expression and multivariate analyses. A list of candidate genes showing functional and/or structural associations with FE was elaborated based on results from both AWM and gene expression analyses, and included the aforementioned TF genes and other ones that have key roles in metabolism, e.g. ESRRG, RXRG, PPARGC1A, TCF7L2, LHX4, MAML2, NFATC3, NFKBIZ, TCEA1, CDCA7L, LZTFL1 or CBFB. The most enriched biological pathways in this list were associated with behaviour, immunity, nervous system, and neurotransmitters, including melatonin, glutamate receptor, and gustation pathways. Finally, an expression GWAS allowed identifying 269 SNPs associated with the candidate genes' expression (eSNPs). Addition of these eSNPs to the AWM panel of 829 SNPs did not improve the accuracy of genomic predictions. CONCLUSIONS: Candidate genes that have a direct or indirect effect on FE-related traits belong to various biological processes that are mainly related to immunity, behaviour, energy metabolism, and the nervous system. The pituitary gland, hypothalamus and thyroid axis, and estrogen signalling play fundamental roles in the regulation of FE in pigs. The 829 selected SNPs explained 61% of the phenotypic variance of RFI, which constitutes a promising perspective for applying genetic selection on FE relying on molecular-based prediction.


Assuntos
Ração Animal , Suínos/genética , Agricultura , Fenômenos Fisiológicos da Nutrição Animal/genética , Animais , Ingestão de Alimentos , Perfilação da Expressão Gênica , Estudo de Associação Genômica Ampla , Fenótipo , Polimorfismo de Nucleotídeo Único , Suínos/crescimento & desenvolvimento
16.
Phys Chem Chem Phys ; 21(41): 23102-23110, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31603174

RESUMO

With the idea of proposing solid state systems that have a high storage capacity of molecular hydrogen, a density functional theory study of magnesium oxide (MgO)n clusters (n = 1-10) was carried out. Hydrogen-magnesium oxide systems presented adsorption energy values in accordance with the previously reported studies of physisorption processes; additionally negative values of ΔGads were found describing adsorption as a favorable process. Here, the (MgO)7 cluster presented the highest adsorption energy. The storage capacity by weight of the magnesium oxide clusters was greater than the recommended percentage (7.5%) by the U.S. Department of Energy. QTAIM analysis and non-covalent index plots highlighted the weak nature of the interaction between the MgO clusters and hydrogen molecules, and the fundamental role of the Mg-O bonds' polarity in the systems' storage capacity.

17.
J Anim Breed Genet ; 136(6): 474-483, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31020712

RESUMO

Models for genetic evaluation of feed efficiency (FE) for animals housed in groups when they are either fed ad libitum (F) or on restricted (R) feeding were implemented. Definitions of FE on F included group records of feed intake ( FI ¯ F ) and individual records of growth rate (GF ) and metabolic weight (MF ). Growth rate (GR ) as FE measurement on R was used. Data corresponded to 5,336 kits from a rabbit sire line, from 1,255 litters in 14 batches and 667 cages. A five-trait mixed model (also with metabolic weight on R, MR ) was implemented including, for each trait, the systematic effects of batch, body weight at weaning, parity order and litter size; and the random effects of litter, additive genetic and individual. A Bayesian analysis was performed. Conditional traits such as FI ¯ F | M F , G F and G F | M F , FI ¯ F were obtained from elements of additive genetics ( FI ¯ F | M F , G F g and G F | M F , FI ¯ F g ) or phenotypic ( FI ¯ F | M F , G F p and G F | M F , FI ¯ F p ) (co)variance matrices. In the first case, heritabilities were low (0.07 and 0.06 for FI ¯ F | M F , G F g and G F | M F , FI ¯ F g , respectively) but null genetic correlation between the conditional and conditioning traits is guaranteed. In the second case, heritabilities were higher (0.22 and 0.16 for FI ¯ F | M F , G F p and G F | M F , FI ¯ F p , respectively) but the genetic correlation between FI ¯ F | M F , G F p and G F was moderate (0.58). Heritability of GR was low (0.08). This trait was negatively correlated with G F | M F , FI ¯ F p and G F | M F , FI ¯ F g of animals on F, which indicate a different genetic background. The correlation between GR and GF was also low to moderate (0.48) and the additive variance of GF was almost four times that of GR , suggesting the presence of a substantial genotype by feeding regimen interaction.


Assuntos
Cruzamento/métodos , Ingestão de Alimentos/genética , Coelhos/genética , Coelhos/fisiologia , Animais , Feminino , Genótipo , Masculino , Estatística como Assunto
18.
Int J Mol Sci ; 20(8)2019 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-31014011

RESUMO

Annona purpurea, known in Mexico as "cabeza de negro" or "ilama", belongs to the Annonaceae family. Its roots are employed in folk medicine in several regions of Mexico. Taking that information into account, a chemical and biological analysis of the components present in the roots of this species was proposed. Our results demonstrated that the dichloromethane (DCM) extract was exclusively constituted by a mixture of five new acetogenins named annopurpuricins A-E (1-5). These compounds have an aliphatic chain of 37 carbons with a terminal α,ß unsaturated γ-lactone. Compounds 1 and 2 belong to the adjacent bis-THF (tetrahydrofuran) α-monohydroxylated type, while compounds 3 and 4 belong to the adjacent bis-THF α,α'-dihydroxylated type; only compound 5 possesses a bis-epoxide system. Complete structure analysis was carried out by spectroscopy and chemical methods. All compounds were evaluated for their antiproliferative activity on three human tumor cell lines (MSTO-211H, HeLa and HepG2). Compounds 1-4 inhibited significantly the growth of HeLa and HepG2 cells, showing GI50 values in the low/subnanomolar range, while 5 was completely ineffective under the tested conditions. The investigation of the mechanism of action responsible for cytotoxicity revealed for the most interesting compound 1 the ability to block the complex I activity on isolated rat liver mitochondria (RLM).


Assuntos
Acetogeninas/química , Annona/química , Raízes de Plantas/química , Acetogeninas/isolamento & purificação , Acetogeninas/farmacologia , Animais , Annona/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Conformação Molecular , Raízes de Plantas/metabolismo , Ratos
19.
Water Sci Technol ; 79(9): 1727-1738, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31241478

RESUMO

The planning and scheduling of maintenance operations of large conventional sewer systems generate a complex decision-making environment due to the difficulty in the collection and analysis of the spatiotemporal information about the operational and structural condition of their components (e.g. pipes, gully pots and manholes). As such, water utilities generally carry out these operations following a corrective approach. This paper studies the impact of the spatiotemporal correlation between these failure events using Log-Gaussian Cox Process (LGCP) models. In addition, the association of failure events to physical and environmental covariates was assessed. The proposed methods were applied to analyze sediment-related blockages in the sewer system of an operative zone in Bogotá (Colombia). The results of this research allowed the identification of significant covariates that were further used to model spatiotemporal clusters with high sediment-related failure risk in sewer systems. The LGCP model proved to be more accurate in comparison to those models that build upon a fundamental assumption that a failure is equally likely to occur at any time regardless of the state of the system and the system's history of failures (i.e. a homogeneous Poisson process model).


Assuntos
Modelos Teóricos , Esgotos , Eliminação de Resíduos Líquidos , Colômbia
20.
Genet Sel Evol ; 50(1): 25, 2018 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-29747574

RESUMO

BACKGROUND: Indirect genetic effects (IGE) are important components of various traits in several species. Although the intensity of social interactions between partners likely vary over time, very few genetic studies have investigated how IGE vary over time for traits under selection in livestock species. To overcome this issue, our aim was: (1) to analyze longitudinal records of average daily gain (ADG) in rabbits subjected to a 5-week period of feed restriction using a structured antedependence (SAD) model that includes IGE and (2) to evaluate, by simulation, the response to selection when IGE are present and genetic evaluation is based on a SAD model that includes IGE or not. RESULTS: The direct genetic variance for ADG (g/d) increased from week 1 to 3 [from 8.03 to 13.47 (g/d)2] and then decreased [6.20 (g/d)2 at week 5], while the indirect genetic variance decreased from week 1 to 4 [from 0.43 to 0.22 (g/d)2]. The correlation between the direct genetic effects of different weeks was moderate to high (ranging from 0.46 to 0.86) and tended to decrease with time interval between measurements. The same trend was observed for IGE for weeks 2 to 5 (correlations ranging from 0.62 to 0.91). Estimates of the correlation between IGE of week 1 and IGE of the other weeks did not follow the same pattern and correlations were lower. Estimates of correlations between direct and indirect effects were negative at all times. After seven generations of simulated selection, the increase in ADG from selection on EBV from a SAD model that included IGE was higher (~ 30%) than when those effects were omitted. CONCLUSIONS: Indirect genetic effects are larger just after mixing animals at weaning than later in the fattening period, probably because of the establishment of social hierarchy that is generally observed at that time. Accounting for IGE in the selection criterion maximizes genetic progress.


Assuntos
Ração Animal , Restrição Calórica/veterinária , Aumento de Peso/genética , Animais , Cruzamento , Simulação por Computador , Feminino , Gado , Estudos Longitudinais , Masculino , Coelhos
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