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BACKGROUND: Polyploidisation often results in genome rearrangements that may involve changes in both the single-copy sequences and the repetitive genome fraction. In this study, we performed a comprehensive comparative analysis of repetitive DNA, with a particular focus on ribosomal DNA (rDNA), in Brachypodium hybridum (2n = 4x = 30, subgenome composition DDSS), an allotetraploid resulting from a natural cross between two diploid species that resemble the modern B. distachyon (2n = 10; DD) and B. stacei (2n = 20; SS). Taking advantage of the recurrent origin of B. hybridum, we investigated two genotypes, Bhyb26 and ABR113, differing markedly in their evolutionary age (1.4 and 0.14 Mya, respectively) and which resulted from opposite cross directions. To identify the origin of rDNA loci we employed cytogenetic and molecular methods (FISH, gCAPS and Southern hybridisation), phylogenetic and genomic approaches. RESULTS: Unlike the general maintenance of doubled gene dosage in B. hybridum, the rRNA genes showed a remarkable tendency towards diploidisation at both locus and unit levels. While the partial elimination of 35S rDNA units occurred in the younger ABR113 lineage, unidirectional elimination of the entire locus was observed in the older Bhyb26 lineage. Additionally, a novel 5S rDNA family was amplified in Bhyb26 replacing the parental units. The 35S and 5S rDNA units were preferentially eliminated from the S- and D-subgenome, respectively. Thus, in the more ancient B. hybridum lineage, Bhyb26, 5S and 35S rRNA genes are likely expressed from different subgenomes, highlighting the complexity of polyploid regulatory networks. CONCLUSION: Comparative analyses between two B. hybridum lineages of distinct evolutionary ages revealed that although the recent lineage ABR113 exhibited an additive pattern of rDNA loci distribution, the ancient lineage Bhyb26 demonstrated a pronounced tendency toward diploidisation manifested by the reduction in the number of both 35S and 5S loci. In conclusion, the age of the allopolyploid appears to be a decisive factor in rDNA turnover in B. hybridum.
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Brachypodium , Evolución Molecular , Filogenia , Poliploidía , Brachypodium/genética , Variación Genética , Genes de ARNr/genética , Genoma de Planta , ARN Ribosómico/genética , ADN Ribosómico/genéticaRESUMEN
STUDY QUESTION: What is the molecular landscape underlying the functional decline of human testicular ageing? SUMMARY ANSWER: The present study provides a comprehensive single-cell transcriptomic atlas of testes from young and old humans and offers insights into the molecular mechanisms and potential targets for human testicular ageing. WHAT IS KNOWN ALREADY: Testicular ageing is known to cause male age-related fertility decline and hypogonadism. Dysfunction of testicular cells has been considered as a key factor for testicular ageing. STUDY DESIGN, SIZE, DURATION: Human testicular biopsies were collected from three young individuals and three old individuals to perform single-cell RNA sequencing (scRNA-seq). The key results were validated in a larger cohort containing human testicular samples from 10 young donors and 10 old donors. PARTICIPANTS/MATERIALS, SETTING, METHODS: scRNA-seq was used to identify gene expression signatures for human testicular cells during ageing. Ageing-associated changes of gene expression in spermatogonial stem cells (SSCs) and Leydig cells (LCs) were analysed by gene set enrichment analysis and validated by immunofluorescent and functional assays. Cell-cell communication analysis was performed using CellChat. MAIN RESULTS AND THE ROLE OF CHANCE: The single-cell transcriptomic landscape of testes from young and old men was surveyed, revealing age-related changes in germline and somatic niche cells. In-depth evaluation of the gene expression dynamics in germ cells revealed that the disruption of the base-excision repair pathway is a prominent characteristic of old SSCs, suggesting that defective DNA repair in SSCs may serve as a potential driver for increased de novo germline mutations with age. Further analysis of ageing-associated transcriptional changes demonstrated that stress-related changes and cytokine pathways accumulate in old somatic cells. Age-related impairment of redox homeostasis in old LCs was identified and pharmacological treatment with antioxidants alleviated this cellular dysfunction of LCs and promoted testosterone production. Lastly, our results revealed that decreased pleiotrophin signalling was a contributing factor for impaired spermatogenesis in testicular ageing. LARGE SCALE DATA: The scRNA-seq sequencing and processed data reported in this paper were deposited at the Genome Sequence Archive (https://ngdc.cncb.ac.cn/), under the accession number HRA002349. LIMITATIONS, REASONS FOR CAUTION: Owing to the difficulty in collecting human testis tissue, the sample size was limited. Further in-depth functional and mechanistic studies are warranted in future. WIDER IMPLICATIONS OF THE FINDINGS: These findings provide a comprehensive understanding of the cell type-specific mechanisms underlying human testicular ageing at a single-cell resolution, and suggest potential therapeutic targets that may be leveraged to address age-related male fertility decline and hypogonadism. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Key Research and Development Program of China (2022YFA1104100), the National Natural Science Foundation of China (32130046, 82171564, 82101669, 82371611, 82371609, 82301796), the Natural Science Foundation of Guangdong Province, China (2022A1515010371), the Major Project of Medical Science and Technology Development Research Center of National Health Planning Commission, China (HDSL202001000), the Open Project of NHC Key Laboratory of Male Reproduction and Genetics (KF202001), the Guangdong Province Regional Joint Fund-Youth Fund Project (2021A1515110921, 2022A1515111201), and the China Postdoctoral Science Foundation (2021M703736). The authors declare no conflict of interest.
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Envejecimiento , Células Intersticiales del Testículo , Análisis de la Célula Individual , Testículo , Transcriptoma , Humanos , Masculino , Testículo/metabolismo , Envejecimiento/genética , Adulto , Células Intersticiales del Testículo/metabolismo , Anciano , Análisis de Secuencia de ARN , Adulto Joven , Persona de Mediana Edad , Células Madre Germinales Adultas/metabolismo , Espermatogénesis/genética , Perfilación de la Expresión GénicaRESUMEN
This study aimed to investigate the effect of hyphal formation in Yarrowia lipolytica and biochar addition on erythritol production by submerged fermentation. Hyphal formation significantly inhibited erythritol production by Y. lipolytica. Transcriptome analysis suggested that the impaired erythritol synthesis of hyphal cells was associated with the differential expression of genes involved in amino acid metabolism, lipid metabolism, and cell wall stability. Deletion of RAS2 responsible for yeast-to-hypha transition and EYD1 included in erythritol degradation blocked hyphal formation and improved erythritol production. Biochar prepared from corncob, sugarcane bagasse (SB), corn straw, peanut shell, coconut shell, and walnut shell (WS) had a positive effect on erythritol production, of which WS pyrolyzed at 500°C (WSc) performed the best in flask fermentation. In a 3.7 L bioreactor, 220.20 ± 10 g/L erythritol with a productivity of 2.30 ± 0.10 g/L/h was obtained in the presence of 1.4% (w/v) WSc and 0.7% SBc (SB pyrolyzed at 500°C) within 96 h. These results suggest that inhibition of hyphal formation together with biochar addition is an efficient way to promote erythritol production.
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Carbón Orgánico , Eritritol , Hifa , Yarrowia , Eritritol/biosíntesis , Eritritol/metabolismo , Yarrowia/genética , Yarrowia/metabolismo , Hifa/crecimiento & desarrollo , Hifa/metabolismo , Hifa/genética , Hifa/efectos de los fármacos , Carbón Orgánico/farmacología , Carbón Orgánico/química , Fermentación , Reactores Biológicos/microbiologíaRESUMEN
INTRODUCTION: Evidence suggests that e-liquid flavor and nicotine concentration are important factors in the initiation and maintenance of e-cigarette use (vaping). Flavors may increase the initiation and maintenance of vaping, and nicotine content is a factor in e-cigarette dependence and the efficacy of e-cigarettes for cigarette smoking cessation. Few human laboratory studies have assessed the joint and interactive effects of flavor and nicotine on subjective responses to e-cigarettes. METHODS: Regular e-cigarette users (N = 89) completed a multi-session study involving a paced vaping procedure with e-liquid cartridges containing their preferred flavor (berry, menthol, or tobacco) or no flavor, with or without nicotine (18 mg). Subjective effects of vaping (satisfaction, reward, aversion, airway sensations, and craving relief) were assessed. RESULTS: Nicotine significantly increased psychological reward and craving relief, whereas flavor significantly increased vaping satisfaction and taste. Nicotine dependence severity moderated the effect of nicotine on reward, such that those with the greatest dependence severity reported the greatest reward. CONCLUSIONS: These findings support differential and noninteractive effects of e-liquid nicotine content and flavor on reinforcing effects of e-cigarettes. IMPLICATIONS: E-liquid flavor and nicotine content have independent, non-interactive effects on subjective responses to vaping under controlled laboratory conditions. Among regular e-cigarette users, vaping a preferred flavor increased taste and satisfaction, but did not interact with nicotine to alter reward or craving. Further research on the ways in which these subjective effects may motivate vaping behavior among different populations of e-cigarette users would be useful to inform regulatory policy of ENDS products.
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Sistemas Electrónicos de Liberación de Nicotina , Productos de Tabaco , Vapeo , Humanos , Nicotina , Aromatizantes , Método Doble Ciego , Vapeo/psicologíaRESUMEN
Functional magnetic resonance imaging has been used to identify complex brain networks by examining the correlation of blood-oxygen-level-dependent signals between brain regions during the resting state. Many of the brain networks identified in adults are detectable at birth, but genetic and environmental influences governing connectivity within and between these networks in early infancy have yet to be explored. We investigated genetic influences on neonatal resting-state connectivity phenotypes by generating intraclass correlations and performing mixed effects modeling to estimate narrow-sense heritability on measures of within network and between-network connectivity in a large cohort of neonate twins. We also used backwards elimination regression and mixed linear modeling to identify specific demographic and medical history variables influencing within and between network connectivity in a large cohort of typically developing twins and singletons. Of the 36 connectivity phenotypes examined, only 6 showed narrow-sense heritability estimates greater than 0.10, with none being statistically significant. Demographic and obstetric history variables contributed to between- and within-network connectivity. Our results suggest that in early infancy, genetic factors minimally influence brain connectivity. However, specific demographic and medical history variables, such as gestational age at birth and maternal psychiatric history, may influence resting-state connectivity measures.
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Mapeo Encefálico , Encéfalo , Embarazo , Femenino , Humanos , Encéfalo/diagnóstico por imagen , Fenotipo , Descanso , Imagen por Resonancia Magnética , Vías Nerviosas/diagnóstico por imagenRESUMEN
Elucidation of the thermotolerance mechanism of erythritol-producing Yarrowia lipolytica is of great significance to breed robust industrial strains and reduce cost. This study aimed to breed thermotolerant Y. lipolytica and investigate the mechanism underlying the thermotolerant phenotype. Yarrowia lipolytica HT34, Yarrowia lipolytica HT36, and Yarrowia lipolytica HT385 that were capable of growing at 34 °C, 36 °C, and 38.5 °C, respectively, were obtained within 150 days (352 generations) by adaptive laboratory evolution (ALE) integrated with 60Co-γ radiation and ultraviolet ray radiation. Comparative genomics analysis showed that genes involved in signal transduction, transcription, and translation regulation were mutated during adaptive evolution. Further, we demonstrated that thermal stress increased the expression of genes related to DNA replication and repair, ceramide and steroid synthesis, and the degradation of branched amino acid (BCAA) and free fatty acid (FFA), while inhibiting the expression of genes involved in glycolysis and the citrate cycle. Erythritol production in thermotolerant strains was remarkably inhibited, which might result from the differential expression of genes involved in erythritol metabolism. Exogenous addition of BCAA and soybean oil promoted the growth of HT385, highlighting the importance of BCAA and FFA in thermal stress response. Additionally, overexpression of 11 out of the 18 upregulated genes individually enabled Yarrowia lipolytica CA20 to grow at 34 °C, of which genes A000121, A003183, and A005690 had a better effect. Collectively, this study provides novel insights into the adaptation mechanism of Y. lipolytica to thermal stress, which will be conducive to the construction of thermotolerant erythritol-producing strains. KEY POINTS: ⢠ALE combined with mutagenesis is efficient for breeding thermotolerant Y. lipolytica ⢠Genes encoding global regulators are mutated during thermal adaptive evolution ⢠Ceramide and BCAA are critical molecules for cells to tolerate thermal stress.
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Yarrowia , Yarrowia/metabolismo , Eritritol , Glicerol/metabolismo , Glucólisis , Ceramidas/metabolismo , Ceramidas/farmacologíaRESUMEN
Aging in humans is intricately linked with alterations in circadian rhythms concomitant with physiological decline and stem cell exhaustion. However, whether the circadian machinery directly regulates stem cell aging, especially in primates, remains poorly understood. In this study, we found that deficiency of BMAL1, the only non-redundant circadian clock component, results in an accelerated aging phenotype in both human and cynomolgus monkey mesenchymal progenitor cells (MPCs). Unexpectedly, this phenotype was mainly attributed to a transcription-independent role of BMAL1 in stabilizing heterochromatin and thus preventing activation of the LINE1-cGAS-STING pathway. In senescent primate MPCs, we observed decreased capacity of BMAL1 to bind to LINE1 and synergistic activation of LINE1 expression. Likewise, in the skin and muscle tissues from the BMAL1-deficient cynomolgus monkey, we observed destabilized heterochromatin and aberrant LINE1 transcription. Altogether, these findings uncovered a noncanonical role of BMAL1 in stabilizing heterochromatin to inactivate LINE1 that drives aging in primate cells.
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Factores de Transcripción ARNTL , Senescencia Celular , Relojes Circadianos , Macaca fascicularis/metabolismo , Factores de Transcripción ARNTL/genética , Factores de Transcripción ARNTL/metabolismo , Animales , Relojes Circadianos/genética , Ritmo Circadiano , Heterocromatina , Macaca fascicularis/genéticaRESUMEN
BACKGROUND: Chronic cough (CC) is common in the general population of China, creating a difficult-to-ignore public health burden. However, there is a lack of research on the nationwide prevalence and disease burden of CC in the Chinese population. We aim to use an insurance claims database to assess the prevalence and the corresponding economic burden owing to CC in China. METHODS: This was a retrospective observational study based on an administrative medical insurance database in 2015, 2016 and 2017, from nine cities in North, South, East, South-West, and North-West regions of China. The study population was Chinese adults (≥ 18 years old) who had been identified as CC patients. Descriptive data analyses were used in statistical analysis. RESULTS: A total of 44,472, 55,565, and 56,439 patients with mean ages of 53.2 (16.3) years were identified as patients with CC in 2015, 2016, and 2017, respectively. Of these, 55.24% were women. In addition, 8.90%, 9.46%, and 8.37% of all patients in 2015, 2016, and 2017, who had applied for medical insurance, had CC, respectively, with a three-year average probability of 8.88%. The median number of outpatient visits within a calendar year was 27 per year due to any reason during the period of 2015-2017. The median medical cost of each patient per year increased from 935.30 USD to 1191.47 USD from 2015 to 2017. CONCLUSION: CC is common among medical insurance users, with a substantial utilization of medical resources, highlighting the huge burden of CC in China.
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Tos Crónica , Costo de Enfermedad , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , China/epidemiología , Tos Crónica/epidemiología , Ciudades/epidemiología , Bases de Datos Factuales , Prevalencia , Estudios RetrospectivosRESUMEN
Tracing the early paths leading to developmental disorders is critical for prevention. In previous work, we detected an interaction between genomic risk scores for schizophrenia (GRSs) and early-life complications (ELCs), so that the liability of the disorder explained by genomic risk was higher in the presence of a history of ELCs, compared with its absence. This interaction was specifically driven by loci harboring genes highly expressed in placentae from normal and complicated pregnancies [G. Ursini et al., Nat. Med. 24, 792-801 (2018)]. Here, we analyze whether fractionated genomic risk scores for schizophrenia and other developmental disorders and traits, based on placental gene-expression loci (PlacGRSs), are linked with early neurodevelopmental outcomes in individuals with a history of ELCs. We found that schizophrenia's PlacGRSs are negatively associated with neonatal brain volume in singletons and offspring of multiple pregnancies and, in singletons, with cognitive development at 1 y and, less strongly, at 2 y, when cognitive scores become more sensitive to other factors. These negative associations are stronger in males, found only with GRSs fractionated by placental gene expression, and not found in PlacGRSs for other developmental disorders and traits. The relationship of PlacGRSs with brain volume persists as an anlage of placenta biology in adults with schizophrenia, again selectively in males. Higher placental genomic risk for schizophrenia, in the presence of ELCs and particularly in males, alters early brain growth and function, defining a potentially reversible neurodevelopmental path of risk that may be unique to schizophrenia.
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Encéfalo/anatomía & histología , Discapacidades del Desarrollo/genética , Predisposición Genética a la Enfermedad , Placenta/metabolismo , Esquizofrenia/genética , Transcriptoma , Encéfalo/fisiología , Cognición , Femenino , Sitios Genéticos , Humanos , Lactante , Recién Nacido , Masculino , Tamaño de los Órganos/genética , EmbarazoRESUMEN
INTRODUCTION: Effective risk communication is essential for achieving patient-centered oral health care, but the limited understanding of patients' subjective perceptions of orthodontic-related risks hinders this process. This study aimed to investigate adults' awareness, concerns, and risk-avoidance behaviors about long-term orthodontic risks, exploring their relationship with psychosocial factors. METHODS: We included 498 adult patients (mean age, 27.3 ± 6.8 years; women, 75.5%) during their initial visits to the orthodontic department at a hospital in Chengdu, China. Participants' understanding of orthodontic risks was gauged before and after exposure to the Oral Health Education Comics (OHEC), a specifically designed digital tool. Concurrently, we used logistic regression models to investigate the associations between patients' depression, anxiety, self-esteem, perfectionism, and dentofacial esthetics with risk perceptions. RESULTS: Approximately 79.5% of participants initially reported low awareness of orthodontic risks, with most knowledge from online sources. Notably, the percentage of participants with high awareness increased to 64.8% after OHEC. The negative facial soft-tissue change was most concerning for participants: 53.4% showed high concerns, and 28.1% showed high avoidance. Furthermore, linear regression indicated positive associations between depression (ß = 0.42 [95% confidence interval {CI}, 0.07-0.77]) and anxiety (ß = 0.76 [95% CI, 0.35-1.18]) with orthodontic risk concerns, whereas risk avoidance was positively associated with depression (ß = 0.62 [95% CI, 0.27-0.97]), anxiety (ß = 1.09 [95% CI, 0.68-1.50]), and perfectionism (ß = 0.24 [95% CI, 0.02-0.46]). CONCLUSIONS: Findings emphasize the imperative of streamlined risk communication in orthodontics. By incorporating comprehensible tools such as OHEC and integrating psychosocial evaluations, more refined patient-practitioner communication and psychosomatic-based dental care can be achieved.
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Comunicación , Humanos , Femenino , Masculino , Adulto , Autoimagen , Ortodoncia , Adulto Joven , China , Estética Dental/psicología , Depresión/psicología , Maloclusión/psicología , Adolescente , Ortodoncia Correctiva/psicologíaRESUMEN
This study aims to explore the potential mechanism of action of Trichosanthis Pericarpium(TP) in improving coronary heart disease(CHD) based on a CHD rat model and metabolomics. The rat model of CHD was built by subcutaneous injection of high-fat diet combined with isoprenaline hydrochloride(ISO). To compare the expression level of lactate dehydrogenase, cardiac troponin â (cTnâ ), creatine kinase-MB(CK-MB), creatine kinase(CK), tumor necrosis factor-α(TNF-α), interleukin-1ß(IL-1ß),interleukin-6(IL-16), hypersensitive C-reactive protein(hs-CRP) in serum and cardiac pathological changes of model animals after administration of TP, LTQ-Orbitrap-MS analysis was combined with principal component analysis. The effect of TP on endogenous metabolites in the feces of CHD rats was studied. In addition, biomarkers were identified using the HMDB database and metabolic pathway enrichment analysis was performed using the MetaboAnalyst online pathway enrichment tool. The content of bile acid was further determined in the feces and serum of different groups of rats. Compared with blank group, the myocardial injury markers(CK,LDH, cTnâ , CK-MB) and inflammatory factors(TNF-α, IL-1ß, IL-6, hs-CRP) in serum of CHD rats were significantly increased.Myocardial injury and inflammatory infiltration in CHD rats were significantly improved by TP extract. The primary bile acid biosynthetic metabolism pathway was enriched by non-targeted metabolome analysis. The levels of total bile acid, primary bile acid,secondary bile acid, and unconjugated bile acids in the feces of CHD rats were significantly lower than those of control rats. Fecal excretion of total bile acid, primary bile acid, and unconjugated bile acid was significantly improved by TP extract. The levels of total bile acid, primary bile acid, secondary bile acid, and unconjugated bile acids in the serum of CHD rats were significantly higher than those of control rats. Circulating blood levels of total bile acids, primary bile acids, secondary bile acids, and unconjugated bile acids were significantly reduced by TP extract. Increasing fecal excretion of bile acid and decreasing the level of bile acid in blood circulation can improve CHD, and maintaining proper bile acid metabolism is one of the mechanisms of TP to improve CHD.
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Ácidos y Sales Biliares , Enfermedad Coronaria , Modelos Animales de Enfermedad , Ratas Sprague-Dawley , Animales , Ratas , Enfermedad Coronaria/tratamiento farmacológico , Enfermedad Coronaria/metabolismo , Ácidos y Sales Biliares/metabolismo , Masculino , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/farmacología , Humanos , Extractos Vegetales/farmacología , Extractos Vegetales/administración & dosificación , Interleucina-6/metabolismo , Interleucina-6/genéticaRESUMEN
Specific DNA-binding to metal ions is a long-standing fundamental research topic with great potential to transform into nano/biotechnology and therapeutics applications. Herein, based on the mobility change of DNA in denaturing gels, we develop a selection strategy to discover a series of 40-45 nt small DNAs that can bind Zn2+ and Cd2+ specifically and tightly. The Zn2+- and Cd2+-bound DNA complexes can even tolerate harsh denaturing conditions of 8 M urea and 50 mM EDTA. The discovery not only exposes a new class of transition metal ion-binding DNAs but also provides potentially a new tool for targeting drug therapies based on metal ions.
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Cadmio , Metales , Metales/metabolismo , ADN/metabolismo , IonesRESUMEN
High-quality radish (Raphanus sativus) genome represents a valuable resource for agronomical trait improvements and understanding genome evolution among Brassicaceae species. However, existing radish genome assembly remains fragmentary, which greatly hampered functional genomics research and genome-assisted breeding. Here, using a NAU-LB radish inbred line, we generated a reference genome of 476.32 Mb with a scaffold N50 of 56.88 Mb by incorporating Illumina, PacBio and BioNano optical mapping techniques. Utilizing Hi-C data, 448.12 Mb (94.08%) of the assembled sequences were anchored to nine radish chromosomes with 40 306 protein-coding genes annotated. In total, 249.14 Mb (52.31%) comprised the repetitive sequences, among which long terminal repeats (LTRs, 30.31%) were the most abundant class. Beyond confirming the whole-genome triplication (WGT) event in R. sativus lineage, we found several tandem arrayed genes were involved in stress response process, which may account for the distinctive phenotype of high disease resistance in R. sativus. By comparing against the existing Xin-li-mei radish genome, a total of 2 108 573 SNPs, 7740 large insertions, 7757 deletions and 84 inversions were identified. Interestingly, a 647-bp insertion in the promoter of RsVRN1 gene can be directly bound by the DOF transcription repressor RsCDF3, resulting into its low promoter activity and late-bolting phenotype of NAU-LB cultivar. Importantly, introgression of this 647-bp insertion allele, RsVRN1In-536 , into early-bolting genotype could contribute to delayed bolting time, indicating that it is a potential genetic resource for radish late-bolting breeding. Together, this genome resource provides valuable information to facilitate comparative genomic analysis and accelerate genome-guided breeding and improvement in radish.
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Raphanus , Raphanus/genética , Genoma de Planta/genética , Fitomejoramiento , Genotipo , CromosomasRESUMEN
Intestinal inflammation modifies host physiology to promote the occurrence of colorectal cancer (CRC), as seen in colitis-associated CRC. Gut microbiota is crucial in cancer progression, primarily by inducing intestinal chronic inflammatory microenvironment, leading to DNA damage, chromosomal mutation, and alterations in specific metabolite production. Therefore, there is an increasing interest in microbiota-based prevention and treatment strategies, such as probiotics, prebiotics, microbiota-derived metabolites, and fecal microbiota transplantation. This review aims to provide valuable insights into the potential correlations between gut microbiota and colitis-associated CRC, as well as the promising microbiota-based strategies for colitis-associated CRC.
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Supercontinuum sources with high compactness are essential for applications such as optical sensing, airborne detection and communication systems. In the past decades, the adoption of bulky optical parametric amplifier to pump various chalcogenide glass waveguides are widely reported for on-chip mid-infrared supercontinuum generation, but this usually leads to a large volume of the whole system, and is not practical. Therefore, integrating advanced femtosecond fiber lasers with optical waveguides using nano-fabrication technology are highly desired. However, the scarcity of compact pump sources and the dispersion-matched high-nonlinearity waveguide in short wavelength regions have hindered the advancement of integrated supercontinuum source performances in the near and mid-infrared region. In this study, we demonstrate a broadband supercontinuum source from As2S3 waveguide pumped by a compact dual-femtosecond solitons pulse source. The laser is completely fiber structured, and its wavelength can be readily tuned from 2 to 2.3â µm using Raman soliton self-frequency shift technology in a Tm3+-doped fiber amplifier. Furthermore, the As2S3 waveguide is designed with controllable dispersion and high nonlinearity for a broadband supercontinuum generation. These results will advance the development of on-chip supercontinuum sources based on chalcogenide waveguides.
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Understanding the growth mechanisms of HgTe nanoparticles (NPs) with varied shapes is crucial for their applications in infrared photodetection. Here, we investigated the growth mechanisms of HgTe NPs with nanorod, sphere, and tetrahedral shapes in depth. The HgTe NPs with a nanorod shape are obtained at low reaction temperatures and formed by breaking tetrapod branches, while HgTe NPs with sphere and tetrahedron shapes have been further achieved at increased reaction temperatures. The systematic crystal analyses demonstrate this effective shape control is related to the synergic effect among the anisotropic passivation of oleylamine, surface free energy, and reaction temperatures. Our findings have deepened the understanding of shape control of the HgTe NPs and inspired a growing passion in the design and engineering of infrared photodetectors using HgTe NPs.
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Hyperhomocysteinemia (HHcy) plays a salient role in male infertility. However, whether HHcy interferes with testosterone production remains inconclusive. Here, we reported a lower serum testosterone level in HHcy mice. Single-cell RNA sequencing revealed that genes related to testosterone biosynthesis, together with nuclear receptor subfamily 5 group A member 1 (Nr5a1), a key transcription factor for steroidogenic genes, were downregulated in the Leydig cells (LCs) of HHcy mice. Mechanistically, Hcy lowered trimethylation of histone H3 on lysine 4 (H3K4me3), which was bound on the promoter region of Nr5a1, resulting in downregulation of Nr5a1. Intriguingly, we identified an unknown cell cluster annotated as Macrophage-like Leydig cells (McLCs), expressing both LCs and macrophages markers. In HHcy mice, McLCs were shifted toward pro-inflammatory phenotype and thus promoted inflammatory response in LC. Betaine supplementation rescued the downregulation of NR5A1 and restored the serum testosterone level in HHcy mice. Overall, our study highlights an etiological role of HHcy in LCs dysfunction.
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Hiperhomocisteinemia , Células Intersticiales del Testículo , Ratones , Masculino , Animales , Células Intersticiales del Testículo/metabolismo , Testosterona , Hiperhomocisteinemia/metabolismo , Macrófagos/metabolismo , Factores de Transcripción/genéticaRESUMEN
High-power laser delivery in the mid-infrared via hollow-core fibers is attractive, but it is too difficult to be fabricated using chalcogenide glasses. Here, we designed a mid-infrared hollow-core anti-resonant chalcogenide fiber (HC-ARCF) with a simplified Kagome cladding micro-structure for the first time. Then, the fiber was firstly fabricated through a precision mechanical drilling and pressured fiber drawing method. Ultra-thin walls of 2µm in the fiber lead to the fewest resonance peaks in the 2-5µm among all reported HC-ARCFs. All the fundamental mode, the second-order mode, tube mode and node mode in the fiber were excited and observed at 1550 nm. The power and spectral properties of the core and cladding of HC-ARCF are studied for the first time. The fiber can deliver high-power of 4.84 W without damage with core-coupling, while the threshold of the node in the cladding is only 3.5 W. A broadening of the output spectrum from 1.96 to 2.41µm due to the high nonlinearity at the node was successfully observed under short-pulse laser pumping at 2µm. The potentials of the fiber used for mid-infrared high-power laser delivery via core, or nonlinear laser generation via node, were thus demonstrated.
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Genetic influences on cortical thickness (CT) and surface area (SA) are known to vary across the life span. Little is known about the extent to which genetic factors influence CT and SA in infancy and toddlerhood. We performed the first longitudinal assessment of genetic influences on variation in CT and SA in 501 twins who were aged 0-2 years. We observed substantial additive genetic influences on both average CT (0.48 in neonates, 0.37 in 1-year-olds, and 0.44 in 2-year-olds) and total SA (0.59 in neonates, 0.74 in 1-year-olds, and 0.73 in 2-year-olds). In addition, we found strong heritability of the change in average CT (0.49) from neonates to 1-year-olds, but not from 1- to 2-year-olds. Moreover, we found strong genetic correlations for average CT (rG = 0.92) between 1- and 2-year-olds and strong genetic correlations for total SA across all timepoints (rG = 0.96 between neonates and 1-year-olds, rG = 1 between 1- and 2-year-olds). In addition, we found CT and SA are strongly genetic correlated at birth, but weaken over time. Overall, results suggest a dynamic genetic relationship between CT and SA during first 2 years of life and provide novel insights into how genetic influences shape the cortical structure during early brain development.
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Corteza Cerebral , Imagen por Resonancia Magnética , Corteza Cerebral/diagnóstico por imagen , Preescolar , Humanos , Lactante , Recién Nacido , Longevidad , Gemelos/genéticaRESUMEN
Sex differences in the human brain emerge as early as mid-gestation and have been linked to sex hormones, particularly testosterone. Here, we analyzed the influence of markers of early sex hormone exposure (polygenic risk score (PRS) for testosterone, salivary testosterone, number of CAG repeats, digit ratios, and PRS for estradiol) on the growth pattern of cortical surface area in a longitudinal cohort of 722 infants. We found PRS for testosterone and right-hand digit ratio to be significantly associated with surface area, but only in females. PRS for testosterone at the most stringent P value threshold was positively associated with surface area development over time. Higher right-hand digit ratio, which is indicative of low prenatal testosterone levels, was negatively related to surface area in females. The current work suggests that variation in testosterone levels during both the prenatal and postnatal period may contribute to cortical surface area development in female infants.