Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
1.
Planta ; 258(2): 45, 2023 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-37462779

RESUMEN

MAIN CONCLUSION: We review the application and the molecular regulation of anthocyanins in colorful Brassica crops, the creation of new germplasm resources, and the development and utilization of colorful Brassica crops. Brassica crops are widely cultivated: these include oilseed crops, such as rapeseed, mustards, and root, leaf, and stem vegetable types, such as turnips, cabbages, broccoli, and cauliflowers. Colorful variants exist of these crop species, and asides from increased aesthetic appeal, these may also offer advantages in terms of nutritional content and improved stress resistances. This review provides a comprehensive overview of pigmentation in Brassica as a reference for the selection and breeding of new colorful Brassica varieties for multiple end uses. We summarize the function and molecular regulation of anthocyanins in Brassica crops, the creation of new colorful germplasm resources via different breeding methods, and the development and multifunctional utilization of colorful Brassica crop types.


Asunto(s)
Brassica napus , Brassica , Brassica/genética , Antocianinas , Fitomejoramiento
2.
Cell Mol Biol Lett ; 28(1): 63, 2023 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-37543634

RESUMEN

BACKGROUND: Nitrogen (N), phosphorus (P) and potassium (K) are critical macronutrients in crops, such that deficiency in any of N, P or K has substantial effects on crop growth. However, the specific commonalities of plant responses to different macronutrient deficiencies remain largely unknown. METHODS: Here, we assessed the phenotypic and physiological performances along with whole transcriptome and metabolomic profiles of rapeseed seedlings exposed to N, P and K deficiency stresses. RESULTS: Quantities of reactive oxygen species were significantly increased by all macronutrient deficiencies. N and K deficiencies resulted in more severe root development responses than P deficiency, as well as greater chlorophyll content reduction in leaves (associated with disrupted chloroplast structure). Transcriptome and metabolome analyses validated the macronutrient-specific responses, with more pronounced effects of N and P deficiencies on mRNAs, microRNAs (miRNAs), circular RNAs (circRNAs) and metabolites relative to K deficiency. Tissue-specific responses also occurred, with greater effects of macronutrient deficiencies on roots compared with shoots. We further uncovered a set of common responders with simultaneous roles in all three macronutrient deficiencies, including 112 mRNAs and 10 miRNAs involved in hormonal signaling, ion transport and oxidative stress in the root, and 33 mRNAs and 6 miRNAs with roles in abiotic stress response and photosynthesis in the shoot. 27 and seven common miRNA-mRNA pairs with role in miRNA-mediated regulation of oxidoreduction processes and ion transmembrane transport were identified in all three macronutrient deficiencies. No circRNA was responsive to three macronutrient deficiency stresses, but two common circRNAs were identified for two macronutrient deficiencies. Combined analysis of circRNAs, miRNAs and mRNAs suggested that two circRNAs act as decoys for miR156 and participate in oxidoreduction processes and transmembrane transport in both N- and P-deprived roots. Simultaneously, dramatic alterations of metabolites also occurred. Associations of RNAs with metabolites were observed, and suggested potential positive regulatory roles for tricarboxylic acids, azoles, carbohydrates, sterols and auxins, and negative regulatory roles for aromatic and aspartate amino acids, glucosamine-containing compounds, cinnamic acid, and nicotianamine in plant adaptation to macronutrient deficiency. CONCLUSIONS: Our findings revealed strategies to rescue rapeseed from macronutrient deficiency stress, including reducing the expression of non-essential genes and activating or enhancing the expression of anti-stress genes, aided by plant hormones, ion transporters and stress responders. The common responders to different macronutrient deficiencies identified could be targeted to enhance nutrient use efficiency in rapeseed.


Asunto(s)
Brassica napus , MicroARNs , Deficiencia de Potasio , Brassica napus/genética , Brassica napus/metabolismo , Fósforo , Deficiencia de Potasio/genética , Nitrógeno/metabolismo , Multiómica , Transcriptoma , Potasio/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Regulación de la Expresión Génica de las Plantas
3.
Int J Mol Sci ; 24(12)2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37373312

RESUMEN

Rapeseed has the ability to absorb cadmium in the roots and transfer it to aboveground organs, making it a potential species for remediating soil cadmium (Cd) pollution. However, the genetic and molecular mechanisms underlying this phenomenon in rapeseed are still unclear. In this study, a 'cadmium-enriched' parent, 'P1', with high cadmium transport and accumulation in the shoot (cadmium root: shoot transfer ratio of 153.75%), and a low-cadmium-accumulation parent, 'P2', (with a cadmium transfer ratio of 48.72%) were assessed for Cd concentration using inductively coupled plasma mass spectrometry (ICP-MS). An F2 genetic population was constructed by crossing 'P1' with 'P2' to map QTL intervals and underlying genes associated with cadmium enrichment. Fifty extremely cadmium-enriched F2 individuals and fifty extremely low-accumulation F2 individuals were selected based on cadmium content and cadmium transfer ratio and used for bulk segregant analysis (BSA) in combination with whole genome resequencing. This generated a total of 3,660,999 SNPs and 787,034 InDels between these two segregated phenotypic groups. Based on the delta SNP index (the difference in SNP frequency between the two bulked pools), nine candidate Quantitative trait loci (QTLs) from five chromosomes were identified, and four intervals were validated. RNA sequencing of 'P1' and 'P2' in response to cadmium was also performed and identified 3502 differentially expressed genes (DEGs) between 'P1' and 'P2' under Cd treatment. Finally, 32 candidate DEGs were identified within 9 significant mapping intervals, including genes encoding a glutathione S-transferase (GST), a molecular chaperone (DnaJ), and a phosphoglycerate kinase (PGK), among others. These genes are strong candidates for playing an active role in helping rapeseed cope with cadmium stress. Therefore, this study not only sheds new light on the molecular mechanisms of Cd accumulation in rapeseed but could also be useful for rapeseed breeding programs targeting this trait.


Asunto(s)
Brassica napus , Cadmio , Humanos , Brassica napus/genética , Fitomejoramiento , Sitios de Carácter Cuantitativo , Análisis de Secuencia de ARN
4.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(4): 456-461, 2020 Apr 28.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-32879072

RESUMEN

Postpartum depression is a kind of mental disorder caused by the comprehensive effects of economics, psychosociology, biology, obstetrics and other characteristic factors in the process of female pregnancy. The pathogenesis of postpartum depression is complicated and has not been clarified. With the process pregnancy, the influence of psychosocial and biology factors are also in dynamic change. The postpartum depression predictor among psychosocial factors are antenatal depression, life events and social supports. Among biological factors, the predictors are hypothalamic-pituitary-thyroid axis and serum lipids. Timely and effective prediction can identify the high-risk population and risk factors for postpartum depression.


Asunto(s)
Depresión Posparto , Complicaciones del Embarazo , Depresión , Femenino , Humanos , Periodo Posparto , Embarazo , Factores de Riesgo
5.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(10): 1215-1222, 2020 Oct 28.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-33268583

RESUMEN

OBJECTIVES: To explore the application of random forest algorithm in screening the risk factors and predictive values for postpartum depression. METHODS: We recruited the participants from a tertiary hospital between June 2017 and June 2018 in Changsha City, and followed up from pregnancy up to 4-6 weeks postpartum.Demographic economics, psychosocial, biological, obstetric, and other factors were assessed at first trimesters with self-designed obstetric information questionnaire and the Chinese version of Edinburgh Postnatal Depression Scale (EPDS). During 4-6 weeks after delivery, the Chinese version of EPDS was used to score depression and self-designed questionnaire to collect data of delivery and postpartum. The data of subjects were randomly divided into the training data set and the verification data set according to the ratio of 3꞉1. The training data set was used to establish the random forest model of postpartum depression, and the verification data set was used to verify the predictive effects via the accuracy, sensitivity, specificity, positive predictive value, negative predictive value, and AUC index. RESULTS: A total of 406 participants were in final analysis. Among them, 150 of whom had EPDS score ≥9, and the incidence of postpartum depression was 36.9%. The predictive effects of random forest model in the verification data set were at accuracy of 80.10%, sensitivity of 61.40%, specificity of 89.10%, positive predictive value of 73.00%, negative predictive value of 82.80%, and AUC index of 0.833. The top 10 predictive influential factors that screening by the variable importance measure in random forest model was antenatal depression, economic worries after delivery, work worries after delivery, free triiodothyronine in first trimesters, high-density lipoprotein in third trimester, venting temper to infants, total serum cholesterol and serum triglyceride in first trimester, hematocrit and serum triglyceride in third trimester. CONCLUSIONS: Random forest has a great advantage in risk prediction for postpartum depression. Through comprehensive evaluation mechanism, it can identify the important influential factors for postpartum depression from complex multi-factors and conduct quantitative analysis, which is of great significance to identify the key factors for postpartum depression and carry out timely and effective intervention.


Asunto(s)
Algoritmos , Depresión Posparto , Depresión Posparto/diagnóstico , Depresión Posparto/epidemiología , Femenino , Humanos , Periodo Posparto , Embarazo , Tercer Trimestre del Embarazo , Escalas de Valoración Psiquiátrica , Factores de Riesgo , Sensibilidad y Especificidad
6.
BMC Plant Biol ; 19(1): 570, 2019 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-31856702

RESUMEN

BACKGROUND: Oilseed rape is an excellent candidate for phytoremediation of cadmium (Cd) contaminated soils given its advantages of high biomass, fast growth, moderate metal accumulation, ease of harvesting, and metal tolerance, but the cadmium response pathways in this species (Brassica napus) have yet to be fully elucidated. A combined analysis of miRNA and mRNA expression to infer Cd-induced regulation has not been reported in B. napus. RESULTS: We characterized concurrent changes in miRNA and mRNA profiles in the roots and shoots of B. napus seedlings after 10 days of 10 mg/L Cd2+ treatment. Cd treatment significantly affected the expression of 22 miRNAs belonging to 11 families in the root and 29 miRNAs belonging to 14 miRNA families in the shoot. Five miRNA families (MIR395, MIR397, MIR398, MIR408 and MIR858) and three novel miRNAs were differentially expressed in both tissues. A total of 399 differentially expressed genes (DEGs) in the root and 389 DEGs in the shoot were identified, with very little overlap between tissue types. Eight anti-regulation miRNA-mRNA interaction pairs in the root and eight in the shoot were identified in response to Cd and were involved in key plant stress response pathways: for example, four genes targeted by miR398 were involved in a pathway for detoxification of superoxide radicals. Cd stress significantly impacted the photosynthetic pathway. Transcription factor activation, antioxidant response pathways and secondary metabolic processes such as glutathione (GSH) and phenylpropanoid metabolism were identified as major components for Cd-induced response in both roots and shoots. CONCLUSIONS: Combined miRNA and mRNA profiling revealed miRNAs, genes and pathways involved in Cd response which are potentially critical for adaptation to Cd stress in B. napus. Close crosstalk between several Cd-induced miRNAs and mRNAs was identified, shedding light on possible mechanisms for response to Cd stress in underground and aboveground tissues in B. napus. The pathways, genes, and miRNAs identified here will be valuable targets for future improvement of cadmium tolerance in B. napus.


Asunto(s)
Brassica napus/efectos de los fármacos , Cadmio/efectos adversos , MicroARNs/genética , ARN Mensajero/genética , ARN de Planta/genética , Contaminantes del Suelo/efectos adversos , Brassica napus/genética , MicroARNs/metabolismo , ARN Mensajero/metabolismo , ARN de Planta/metabolismo , Plantones/efectos de los fármacos , Plantones/genética , Estrés Fisiológico , Transcriptoma
7.
Planta ; 250(1): 23-40, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30993403

RESUMEN

MAIN CONCLUSION: This review will provide evidence for the indispensable function of these elements in regulating plant development and resistance to biotic and abiotic stresses, as well as their evolutionary role in facilitating plant adaptation. Over millions of years of evolution, plant genomes have acquired a complex constitution. Plant genomes consist not only of protein coding sequences, but also contain large proportions of non-coding sequences. These include introns of protein-coding genes, and intergenic sequences such as non-coding RNA, repeat sequences and transposable elements. These non-coding sequences help to regulate gene expression, and are increasingly being recognized as playing an important role in genome organization and function. In this review, we summarize the known molecular mechanisms by which gene expression is regulated by several species of non-coding RNAs (microRNAs, long non-coding RNAs, and circular RNAs) and by transposable elements. We further discuss how these non-coding RNAs and transposable elements evolve and emerge in the genome, and the potential influence and importance of these non-coding RNAs and transposable elements in plant development and in stress responses.


Asunto(s)
Elementos Transponibles de ADN/genética , Genoma de Planta/genética , Desarrollo de la Planta , Fenómenos Fisiológicos de las Plantas , Plantas/genética , ARN no Traducido/genética , Intrones/genética , MicroARNs/genética , ARN/genética , ARN Circular , ARN Largo no Codificante/genética , ARN de Planta/genética , Estrés Fisiológico
8.
Planta ; 244(3): 607-22, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27107747

RESUMEN

MAIN CONCLUSION: Small RNAs and microRNAs were found to vary extensively in synthetic Brassica napus and subsequent generations, accompanied by the activation of transposable elements in response to hybridization and polyploidization. Resynthesizing B. napus by hybridization and chromosome doubling provides an approach to create novel polyploids and increases the usable genetic variability in oilseed rape. Although many studies have shown that small RNAs (sRNAs) act as important factor during hybridization and polyploidization in plants, much less is known on how sRNAs change in synthetic B. napus, particularly in subsequent generations after formation. We performed high-throughput sequencing of sRNAs in S1-S4 generations of synthetic B. napus and in the homozygous B. oleracea and B. rapa parent lines. We found that the number of small RNAs (sRNAs) and microRNAs (miRNAs) doubled in synthetic B. napus relative to the parents. The proportions of common sRNAs detected varied from the S1 to S4 generations, suggesting sRNAs are unstable in synthetic B. napus. The majority of miRNAs (67.2 %) were non-additively expressed in the synthesized Brassica allotetraploid, and 33.3 % of miRNAs were novel in the resynthesized B. napus. The percentage of miRNAs derived from transposable elements (TEs) also increased, indicating transposon activation and increased transposon-associated miRNA production in response to hybridization and polyploidization. The number of target genes for each miRNA in the synthesized Brassica allotetraploid was doubled relative to the parents, enhancing the complexity of gene expression regulation. The potential roles of miRNAs and their targets are discussed. Our data demonstrate generational changes in sRNAs and miRNAs in synthesized B. napus.


Asunto(s)
Brassica napus/genética , Hibridación Genética , MicroARNs/metabolismo , Brassica napus/metabolismo , Elementos Transponibles de ADN
9.
Funct Integr Genomics ; 14(1): 23-9, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24132513

RESUMEN

Horizontal gene transfer (HGT) describes the transmission of genetic material across species boundaries. HGT often occurs in microbic and eukaryotic genomes. However, the pathways by which HGTs occur in multicellular eukaryotes, especially in plants, are not well understood. We systematically summarized more than ten possible pathways for HGT. The intimate contact which frequently occurs in parasitism, symbiosis, pathogen, epiphyte, entophyte, and grafting interactions could promote HGTs between two species. Besides these direct transfer methods, genes can be exchanged with a vector as a bridge: possible vectors include pollen, fungi, bacteria, viruses, viroids, plasmids, transposons, and insects. HGT, especially when involving horizontal transfer of transposable elements, is recognized as a significant force propelling genomic variation and biological innovation, playing an important functional and evolutionary role in both eukaryotic and prokaryotic genomes. We proposed possible mechanisms by which HGTs can occur, which is useful in understanding the genetic information exchange among distant species or distant cellular components.


Asunto(s)
Transferencia de Gen Horizontal , Plantas/genética , Animales , Bacterias/genética , Elementos Transponibles de ADN , Hongos/genética , Interacciones Huésped-Patógeno/genética , Insectos/genética , Plantas/microbiología , Plantas/parasitología , Plantas/virología , Plastidios/genética , Virus/genética
10.
J Mol Evol ; 78(1): 38-49, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24271856

RESUMEN

Allopolyploidization, where two species come together to form a new species, plays a major role in speciation and genome evolution. Transfer RNAs (abbreviated tRNA) are typically 73-94 nucleotides in length, and are indispensable in protein synthesis, transferring amino acids to the cell protein synthesis machinery (ribosome). To date, the regularity and function of tRNA gene sequence variation during the process of allopolyploidization have not been well understood. In this study, the inter-tRNA gene corresponding to tRNA amplification polymorphism method was used to detect changes in tRNA gene sequences in the progeny of interspecific hybrids between Brassica rapa and B. oleracea, mimicking the original B. napus (canola) species formation event. Cluster analysis showed that tRNA gene variation during allopolyploidization did not appear to have a genotypic basis. Significant variation occurred in the early generations of synthetic B. napus (F1 and F2 generations), but fewer alterations were observed in the later generation (F3). The variation-prone tRNA genes tended to be located in AT-rich regions. BlastN analysis of novel tRNA gene variants against a Brassica genome sequence database showed that the variation of these tRNA-gene-associated sequences in allopolyploidization might result in variation of gene structure and function, e.g., metabolic process and transport.


Asunto(s)
Brassica napus/genética , Especiación Genética , ARN de Transferencia/genética , Secuencia de Bases , Evolución Molecular , Genes de Plantas , Variación Genética , Análisis de Secuencia de ARN
11.
Int J Gynaecol Obstet ; 164(3): 857-868, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37605982

RESUMEN

BACKGROUND: Polycystic ovary syndrome (PCOS) is a common chronic condition in women of child-bearing age. There is currently no effective treatment, so early and long-term management is essential. However, there are many problems in the practice of disease management in women with PCOS that make it difficult to achieve good outcomes. OBJECTIVE: To explore women's experience of PCOS management and identify the relevant facilitators and barriers to management. SEARCH STRATEGY: A structured search was undertaken in five bibliographic databases (MEDLINE, Web of Science, CINAHL, Embase, PubMed, and Cochrane) from the date of establishment of the database up to December 2022. SELECTION CRITERIA: All qualitative and mixed-methods studies available in English describing the experience of PCOS management from the patients' perspective were included. DATA COLLECTION AND ANALYSIS: The Joanna Briggs Institute Qualitative Assessment and Review Instrument was used to appraise study quality. The evidence was synthesized using a pragmatic meta-aggregative approach guided by the capability, opportunity, and motivation model of behavior (COM-B). MAIN RESULTS: A total of 13 studies were included with 85 equivocal findings and 12 credible findings. The findings were meta-aggregated into three themes: (1) capability of women with PCOS, including patients' attitudes toward disease and management, knowledge, and skills of the disease; (2) opportunities in PCOS management, including information about PCOS, diagnostic delay, disease characteristics, disease management plan, and logistical and environmental problems; and (3) motivation in PCOS management, including impact of symptoms, perceived needs, support and feedback, and unpleasant medical experience. CONCLUSIONS: This study identifies facilitators and barriers to PCOS management from the patient perspective, which can guide the design and implementation of PCOS management programs for patients. This study also provides information for future research into how the COM-B theory can be incorporated into specific management plans to promote patient action.


Asunto(s)
Síndrome del Ovario Poliquístico , Humanos , Femenino , Síndrome del Ovario Poliquístico/diagnóstico , Síndrome del Ovario Poliquístico/terapia , Diagnóstico Tardío , Motivación
12.
Commun Biol ; 7(1): 375, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38548869

RESUMEN

Protein methylation is a commonly posttranslational modification of transcriptional regulators to fine-tune protein function, however, whether this regulation strategy participates in the regulation of lignocellulase synthesis and secretion in Trichoderma reesei remains unexplored. Here, a putative protein methyltransferase (TrSAM) is screened from a T. reesei mutant with the ability to express heterologous ß-glucosidase efficiently even under glucose repression. The deletion of its encoding gene trsam causes a significant increase of cellulase activities in all tested T. reesei strains, including transformants of expressing heterologous genes using cbh1 promotor. Further investigation confirms that TrSAM interacts with the cellulase negative regulator ACE1 via its amino acid residue Arg383, which causes a decrease in the ACE1-DNA binding affinity. The enzyme activity of a T. reesei strain harboring ACE1R383Q increases by 85.8%, whereas that of the strains with trsam or ace1 deletion increases by more than 100%. By contrast, the strain with ACE1R383K shows no difference to the parent strain. Taken together, our results demonstrate that TrSAM plays an important role in regulating the expression of cellulase and heterologous proteins initiated by cbh1 promotor through interacting with ACE1R383. Elimination and mutation of TrSAM and its downstream ACE1 alleviate the carbon catabolite repression (CCR) in expressing cellulase and heterologous protein in varying degrees. This provides a new solution for the exquisite modification of T. reesei chassis.


Asunto(s)
Celulasa , Hypocreales , Celulasa/genética , Celulasa/metabolismo , Regiones Promotoras Genéticas , Mutación , Expresión Génica
13.
Midwifery ; 132: 103973, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38442529

RESUMEN

BACKGROUND: Although the stigma associated with seeking professional psychological help has received significant attention, few studies have focused on the status and factors influencing this stigma among pregnant women, especially those with a Chinese cultural background. This study aimed to assess the status of stigma associated with seeking professional psychological help and its influencing factors. METHODS: A total of 1325 pregnant women were recruited from Hunan Province, China. The Stigma for Seeking Professional Psychological Help questionnaire, Patient Health Questionnaire-9, Perceived Social Support Scale, Simplified Coping Style Questionnaire, and questionnaires on sociodemographic characteristics and pregnancy-related information were used. Descriptive, univariate, correlation, and multivariate linear regression analyses were used to investigate the status of stigma and identify its influencing factors. FINDINGS: Pregnant Chinese women experienced a mild to moderate level of stigma associated with seeking professional psychological help, and self-stigma was more common than social stigma associated with seeking psychological help. The results of the multivariate analysis suggested that perceived social support, positive coping styles, negative coping styles, and depressive symptoms were the factors influencing self-stigma and social stigma associated with seeking professional psychological help. Advanced age and a low educational level were the only predictors associated with self-stigma, while a history of multiple pregnancies had an effect only on social stigma associated with seeking professional psychological help. CONCLUSION: Chinese pregnant women experienced a mild to moderate level of stigma associated with seeking professional psychological help. Destigmatizing interventions focusing on self-stigma and social stigma should be designed according to maternal characteristics, social support, coping style, and depressive symptoms.


Asunto(s)
Mujeres Embarazadas , Estigma Social , Humanos , Femenino , Embarazo , Adulto , Estudios Transversales , China , Mujeres Embarazadas/psicología , Encuestas y Cuestionarios , Apoyo Social , Adaptación Psicológica , Aceptación de la Atención de Salud/psicología , Aceptación de la Atención de Salud/estadística & datos numéricos , Conducta de Búsqueda de Ayuda
14.
Micromachines (Basel) ; 15(4)2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38675305

RESUMEN

As a type of ultra-high strength steel, AerMet100 steel is used in the aerospace and military industries. Due to the fact that AerMet100 steel is difficult to machine, people have been exploring the process of additive manufacturing to fabricate AerMet100 steel. In this study, AerMet100 steel was produced using an in situ rolling hybrid with wire arc additive manufacturing. Microstructure, tensile properties, and fracture toughness of as-deposited and heat-treated AerMet100 steel were evaluated in different directions. The results reveal that the manufacturing process leads to grain fragmentation and obvious microstructural refinement of the AerMet100 steel, and weakens the anisotropy of the mechanical properties. After heat treatment, the microstructure of the AerMet100 steel is mainly composed of lath martensite and reversed austenite. Alloy carbides are precipitated within the martensitic matrix, and a high density of dislocations is the primary strengthening mechanism. The existence of film-like austenite among the martensite matrix enhances the toughness of AerMet100 steel, which coordinates stress distribution and restrains crack propagation, resulting in an excellent balance between strength and toughness. The AerMet100 steel with in situ rolling is isotropy and achieves the following values: an average ultimate strength of 1747.7 ± 16.3 MPa, yield strength of 1615 ± 40.6 MPa, elongation of 8.3 ± 0.2% in deposition direction, and corresponding values in the building direction are 1821.3 ± 22.1 MPa, 1624 ± 84.5 MPa, and 7.6 ± 1.7%, and the KIC value up to 70.6 MPa/m0.5.

15.
Int J Biol Macromol ; 269(Pt 2): 131954, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38697424

RESUMEN

Silk fibroin (SF) from the cocoon of silkworm has exceptional mechanical properties and biocompatibility and is used as a biomaterial in a variety of fields. Sustainable, affordable, and scalable manufacturing of SF would enable its large-scale use. We report for the first time the high-level secretory production of recombinant SF peptides in engineered Pichia pastoris cell factories and the processing thereof to nanomaterials. Two SF peptides (BmSPR3 and BmSPR4) were synthesized and secreted by P. pastoris using signal peptides and appropriate spacing between hydrophilic sequences. By strain engineering to reduce protein degradation, increase glycyl-tRNA supply, and improve protein secretion, we created the optimized P. pastoris chassis PPGSP-8 to produce BmSPR3 and BmSPR4. The SF fed-batch fermentation titers of the resulting two P. pastoris cell factories were 11.39 and 9.48 g/L, respectively. Protein self-assembly was inhibited by adding Tween 80 to the medium. Recombinant SF peptides were processed to nanoparticles (NPs) and nanofibrils. The physicochemical properties of nanoparticles R3NPs and R4NPs from the recombinant SFs synthesized in P. pastoris cell factories were similar or superior to those of RSFNPs (Regenerated Silk Fibroin NanoParticles) originating from commercially available SF. Our work will facilitate the production by microbial fermentation of functional SF for use as a biomaterial.


Asunto(s)
Fibroínas , Proteínas Recombinantes , Fibroínas/química , Fibroínas/biosíntesis , Fibroínas/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/biosíntesis , Nanoestructuras/química , Fermentación , Saccharomycetales/metabolismo , Saccharomycetales/genética , Seda/química , Seda/biosíntesis , Animales , Bombyx/metabolismo , Bombyx/genética
16.
Planta ; 238(6): 1005-24, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24062086

RESUMEN

Next-generation sequencing (NGS) produces numerous (often millions) short DNA sequence reads, typically varying between 25 and 400 bp in length, at a relatively low cost and in a short time. This revolutionary technology is being increasingly applied in whole-genome, transcriptome, epigenome and small RNA sequencing, molecular marker and gene discovery, comparative and evolutionary genomics, and association studies. The Brassica genus comprises some of the most agro-economically important crops, providing abundant vegetables, condiments, fodder, oil and medicinal products. Many Brassica species have undergone the process of polyploidization, which makes their genomes exceptionally complex and can create difficulties in genomics research. NGS injects new vigor into Brassica research, yet also faces specific challenges in the analysis of complex crop genomes and traits. In this article, we review the advantages and limitations of different NGS technologies and their applications and challenges, using Brassica as an advanced model system for agronomically important, polyploid crops. Specifically, we focus on the use of NGS for genome resequencing, transcriptome sequencing, development of single-nucleotide polymorphism markers, and identification of novel microRNAs and their targets. We present trends and advances in NGS technology in relation to Brassica crop improvement, with wide application for sophisticated genomics research into agronomically important polyploid crops.


Asunto(s)
Brassica/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Empalme Alternativo , Brassica napus/genética , Mapeo Cromosómico , ADN de Plantas/genética , Perfilación de la Expresión Génica , Genoma de Planta , Secuenciación de Nucleótidos de Alto Rendimiento/tendencias , MicroARNs/genética , Fitomejoramiento , Polimorfismo de Nucleótido Simple , ARN de Planta/genética , Análisis de Secuencia de ADN , Análisis de Secuencia de ARN
17.
Genomics ; 100(4): 222-30, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22800764

RESUMEN

The movement of transposable elements (TE) in eukaryotic genomes can often result in the occurrence of nested TEs (the insertion of TEs into pre-existing TEs). We performed a general TE assessment using available databases to detect nested TEs and analyze their characteristics and putative functions in eukaryote genomes. A total of 802 TEs were found to be inserted into 690 host TEs from a total number of 11,329 TEs. We reveal that repetitive sequences are associated with an increased occurrence of nested TEs and sequence biased of TE insertion. A high proportion of the genes which were associated with nested TEs are predicted to localize to organelles and participate in nucleic acid and protein binding. Many of these function in metabolic processes, and encode important enzymes for transposition and integration. Therefore, nested TEs in eukaryotic genomes may negatively influence genome expansion, and enrich the diversity of gene expression or regulation.


Asunto(s)
Elementos Transponibles de ADN/genética , Eucariontes/genética , Genoma , Elementos de Nucleótido Esparcido Largo/genética , Elementos de Nucleótido Esparcido Corto/genética , Animales , Evolución Molecular , Regulación de la Expresión Génica , Repeticiones de Microsatélite/genética , Anotación de Secuencia Molecular , Programas Informáticos
18.
Psychiatry Res ; 328: 115467, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37690191

RESUMEN

Few studies focused on the trajectory of perinatal suicidal ideation from early pregnancy and covered whole routine perinatal periods. This study aimed to investigate the prevalence of suicidal ideation from early pregnancy to six weeks postpartum, and further explore the trajectories of perinatal suicidal ideation and their risk factors. A prospective longitudinal study was conducted in a comprehensive tertiary hospital in Hunan province, China among 1089 participants. Perinatal suicidal ideation and depression were assessed by item 9 of Patient Health Questionnaire 9 and the remaining eight items. Sociodemographic and psychological factors were collected by self-reported comprehensive questionnaires. Latent Growth Curve and Growth Mixture Modeling were used to identify the trajectories of suicidal ideation and logistic regression was used to explore risk factors of trajectories. A total of 629 participants were included. The prevalence of suicidal ideation was 16.4% from early pregnancy to six weeks postpartum, with 12.1% in pregnancy and 7.8% in postpartum. Two trajectories were identified: "persistent low levels of suicidal ideation" (92.9%) and "persistent high levels of suicidal ideation" (7.1%). 40.63% of women who screened positive for suicidal ideation during early pregnancy were in the "persistent high level of suicidal ideation" trajectory. A low level of neuroticism and anxiety symptoms during early pregnancy was associated with "persistent high levels of suicidal ideation". In conclusion, suicidal ideation of women during the perinatal period was dynamic, Suicidal ideation screening and identification in early pregnancy should be addressed for perinatal women to facilitate timely early interventions.


Asunto(s)
Periodo Posparto , Ideación Suicida , Embarazo , Femenino , Humanos , Estudios Prospectivos , Estudios Longitudinales , Periodo Posparto/psicología , Factores de Riesgo , Depresión/epidemiología , Depresión/diagnóstico
19.
Midwifery ; 122: 103686, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37119670

RESUMEN

OBJECTIVE: To identify barriers and facilitators related to psychological help-seeking behaviors of perinatal depression from all related stakeholders (e.g., perinatal women, family members, mental health care providers, and policymakers). DESIGN: A literature search of six English-language databases (PubMed, Web of Science, Embase, PsycINFO, the Cochrane Library, CINAHL) and three Chinese-language databases (China National Knowledge Infrastructure, Wan Fang, Chinese Biomedical Literature Databases). Studies published in English or Chinese using qualitative or mixed methods to explore the psychological help-seeking behaviors of women with perinatal depression were included. Data extraction was synthesized for common themes based on the Consolidated Framework for Implementation Research. The Joanna Briggs Institute Qualitative Assessment and Review Instrument was used to appraise methodologic quality. PARTICIPANTS AND SETTINGS: Perinatal women with depression, mental health care providers (e.g., pediatricians/nurses, social workers, nurse-midwives, perinatal psychiatrists, community health workers, and administrators), partners and informal caregivers (e.g., community birth attendants, elderly mothers, and men of reproductive age) based in high, middle and low income countries. FINDINGS: Forty-three articles were included in this review and presented according to the Consolidated Framework for Implementation Research domains (in parentheses). The most common barriers to help seeking were stigma (individual characteristics), misconceptions (individual characteristics), cultural beliefs (inner setting), and lack of social support (outer setting). The most common facilitators were providing adequate support (outer setting) and perinatal health care professional training on how to detect, manage and discuss depression; establishing supportive relationships with mental health care providers; and eroding stigma (all three implementation processes). KEY CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: This systematic review could serve as a reference framework for health authorities to develop diverse strategies for improving the psychological help-seeking behaviors of women with perinatal depression. More high-quality studies focused on the Consolidated Framework for Implementation Research characteristics of available interventions, and implementation processes are needed in future research.


Asunto(s)
Depresión , Conducta de Búsqueda de Ayuda , Embarazo , Masculino , Femenino , Humanos , Anciano , Parto , Atención a la Salud , Madres , Investigación Cualitativa
20.
Artículo en Inglés | MEDLINE | ID: mdl-36767654

RESUMEN

A low help-seeking intention for depression is an important reason for the low number of women with perinatal depression who have sought professional help. However, evidence of help-seeking intentions for depression is still lacking in Chinese perinatal women. We aimed to investigate the help-seeking intention for depression and its associated factors among Chinese perinatal women. Participants were recruited from three comprehensive hospitals in Changsha. A total of 874 perinatal women were included in the study. The score for the help-seeking intention for depression in Chinese perinatal women was 3.65 ± 0.79, with about half of participants (58.3%) reporting that they were "likely" and "strongly likely" to seek professional help if they suffered from depression during the perinatal period. Favorable help-seeking attitudes and sufficient knowledge of mental illness help-seeking resources were positively associated with help-seeking intentions for depression. However, self-stigma decreased the help-seeking intention for depression. Chinese perinatal women had relatively positive help-seeking intentions for depression. Reducing the stigma of mental illness and help-seeking, enhancing mental health literacy, and improving attitudes toward professional psychological help-seeking of perinatal women may be the potential key components of interventions to encourage perinatal women to actively seek professional psychological help.


Asunto(s)
Conducta de Búsqueda de Ayuda , Intención , Embarazo , Humanos , Femenino , Estudios Transversales , Depresión , Pueblos del Este de Asia , Salud Mental , Estigma Social , Aceptación de la Atención de Salud/psicología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA