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1.
Opt Express ; 30(10): 16847-16855, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-36221519

RESUMO

We propose a lithography-free wide-angle polarization-insensitive ultra-broadband absorber by using three pairs of tungsten (W) and calcium fluoride (CaF2) films. The simulation results show that the absorptivity is larger than 0.9 with normal incidence in the wavelength range from 400 nm to 1529 nm. By adding a pair of CaF2-W films, we can get a broader absorption bandwidth with absorptivity larger than 0.9 over the wavelength of 400-1639 nm. In addition, the absorption performance is insensitive to the polarization and angle of incidence. The electric field distributions at the absorption peaks show that the absorption is originated from the destructive interference between the reflection waves from the top and bottom interfaces of the multilayer CaF2-W films. Furthermore, the ultra-broad bandwidth is attributed to the anti-reflection effect from the increased effective refractive index from top to down of the proposed absorber. Such physical mechanism of broadening bandwidth based on anti-reflection effect provides a new idea for the design of broadband absorber. Meanwhile, this broadband absorber is a good candidate for potential applications such as detection and energy harvesting.

2.
Biochem Biophys Res Commun ; 576: 1-6, 2021 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-34474244

RESUMO

Wnt signaling is one of the major signaling pathways that regulate cell differentiation, tissue patterning and stem cell homeostasis and its dysfunction causes many human diseases, such as cancer. It is of tremendous interests to understand how Wnt signaling is regulated in a precise manner both temporally and spatially. Naked cuticle (Nkd) acts as a negative-feedback inhibitor for Wingless (Wg, a fly Wnt) signaling in Drosophila embryonic development. However, the role of Nkd remains controversial in later fly development, particularly on the canonical Wg pathway. In the present study, we show that nkd is essential for wing pattern formation, such that both gain and loss of nkd result in the disruption of Wg target expression in larvae stage and abnormal adult wing morphologies. Furthermore, we demonstrate that a thirty amino acid fragment in Nkd, identified previously in Wharton lab, is critical for the canonical Wg signaling, but is dispensable for Wg/planar cell polarity pathway. Putting aside the pleiotropic nature of nkd function, i.e. its role in the Decapentaplegic signaling, we conclude that Nkd universally inhibits the canonical Wg pathway across a life span of Drosophila development.


Assuntos
Proteínas de Drosophila/antagonistas & inibidores , Proteínas de Drosophila/genética , Drosophila/crescimento & desenvolvimento , Via de Sinalização Wnt , Proteína Wnt1/antagonistas & inibidores , Animais , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Retroalimentação Fisiológica , Regulação da Expressão Gênica no Desenvolvimento , Transdução de Sinais
3.
Theor Appl Genet ; 134(8): 2443-2457, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34032878

RESUMO

KEY MESSAGE: In polyploids, linkage mapping is carried out using genotyping with discrete dosage scores. Here, we use probabilistic genotypes and we validate it for the construction of polyploid linkage maps. Marker genotypes are generally called as discrete values: homozygous versus heterozygous in the case of diploids, or an integer allele dosage in the case of polyploids. Software for linkage map construction and/or QTL analysis usually relies on such discrete genotypes. However, it may not always be possible, or desirable, to assign definite values to genotype observations in the presence of uncertainty in the genotype calling. Here, we present an approach that uses probabilistic marker dosages for linkage map construction in polyploids. We compare our method to an approach based on discrete dosages, using simulated SNP array and sequence reads data with varying levels of data quality. We validate our approach using experimental data from a potato (Solanum tuberosum L.) SNP array applied to an F1 mapping population. In comparison to the approach based on discrete dosages, we mapped an additional 562 markers. All but three of these were mapped to the expected chromosome and marker position. For the remaining three markers, no physical position was known. The use of dosage probabilities is of particular relevance for map construction in polyploids using sequencing data, as these often result in a higher level of uncertainty regarding allele dosage.


Assuntos
Mapeamento Cromossômico/métodos , Cromossomos de Plantas/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Poliploidia , Locos de Características Quantitativas , Solanum tuberosum/genética , Simulação por Computador , Proteínas de Plantas/genética , Polimorfismo de Nucleotídeo Único , Solanum tuberosum/crescimento & desenvolvimento
4.
Biochem Biophys Res Commun ; 503(2): 1148-1153, 2018 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-29959918

RESUMO

Magnesium transporter subtype 1 (MagT1) is a magnesium membrane transporter with channel like properties. We have previously identified MagT1 (CG7830) in Drosophila genome and characterized its protein product by electrophysiological means. Here, we report the generation of fly MagT1 mutants and show that MagT1 is essential for early embryonic development. In wings and primordial wings, by clonal analysis and RNAi knock down of MagT1, we have found that loss of MagT1 results in enhanced/ectopic Wingless (Wg, a fly Wnt) signaling and disrupted Decapentaplegic (Dpp) signaling, indicating the crucial role of MagT1 for fly development at later stages. Finally, we demonstrate directly that magnesium transportations are proportional with the MagT1 expressional levels in Drosophila S2  cells. Taken together, these findings may suggest that MagT1 is a major magnesium transporter/channel profoundly involved in fly development by affecting developmental signaling pathways, such as Wg and Dpp signaling.


Assuntos
Proteínas de Transporte de Cátions/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila/embriologia , Transdução de Sinais , Asas de Animais/embriologia , Proteína Wnt1/metabolismo , Animais , Proteínas de Transporte de Cátions/genética , Linhagem Celular , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/genética , Feminino , Magnésio/metabolismo , Masculino , Mutação , Asas de Animais/metabolismo , Via de Sinalização Wnt
5.
Opt Express ; 25(25): 32080-32089, 2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-29245873

RESUMO

A graphene-based tunable ultra-narrowband mid-infrared TE-polarization absorber is proposed. The simulation results show that, the absorption peak can be tuned from 5.43896µm to 5.41418µm, by tuning the Fermi level of graphene from 0.2eV to 1.0eV. The simulation results also show that the absorption bandwidth is less than 1.0nm and the absorption rate is more than 0.99 for TE-polarization (electric field is parallel to grating grooves) in the tuning wavelength range. The ultra-narrowband absorption mechanism is originated from the low power loss in the guided-mode resonance. The tuning function is mainly attributed to the change of the real part of the graphene's permittivity. This tunable ultra-narrowband mid-infrared absorber has potential applications in the tunable filtering and tunable coherent emission of thermal source.

6.
Theor Appl Genet ; 130(12): 2527-2541, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28852802

RESUMO

KEY MESSAGE: We constructed the first integrated genetic linkage map in a polysomic hexaploid. This enabled us to estimate inheritance of parental haplotypes in the offspring and detect multi-allelic QTL. Construction and use of linkage maps are challenging in hexaploids with polysomic inheritance. Full map integration requires calculations of recombination frequency between markers with complex segregation types. In addition, detection of QTL in hexaploids requires information on all six alleles at one locus for each individual. We describe a method that we used to construct a fully integrated linkage map for chrysanthemum (Chrysanthemum × morifolium, 2n = 6x = 54). A bi-parental F1 population of 406 individuals was genotyped with an 183,000 SNP genotyping array. The resulting linkage map consisted of 30,312 segregating SNP markers of all possible marker dosage types, representing nine chromosomal linkage groups and 107 out of 108 expected homologues. Synteny with lettuce (Lactuca sativa) showed local colinearity. Overall, it was high enough to number the chrysanthemum chromosomal linkage groups according to those in lettuce. We used the integrated and phased linkage map to reconstruct inheritance of parental haplotypes in the F1 population. Estimated probabilities for the parental haplotypes were used for multi-allelic QTL analyses on four traits with different underlying genetic architectures. This resulted in the identification of major QTL that were affected by multiple alleles having a differential effect on the phenotype. The presented linkage map sets a standard for future genetic mapping analyses in chrysanthemum and closely related species. Moreover, the described methods are a major step forward for linkage mapping and QTL analysis in hexaploids.


Assuntos
Mapeamento Cromossômico , Chrysanthemum/genética , Ligação Genética , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Alelos , Marcadores Genéticos , Genoma de Planta , Técnicas de Genotipagem , Haplótipos , Lactuca/genética , Fenótipo , Poliploidia , Sintenia
7.
Front Med (Lausanne) ; 11: 1327809, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38898936

RESUMO

Background and aim: There is still uncertainty regarding whether hepatitis C virus (HCV) infection is associated with colorectal cancer (CRC). This study aims to investigate the potential association between HCV infection and CRC through a systematic review and meta-analysis of cohort studies. Methods: PubMed, Embase, and Web of Science were systematically searched from the beginning of their inception to October 2023 to find relevant cohort studies on the association between HCV infection and CRC risk. The random-effect, generic inverse variance method was used to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) for CRC outcome among individuals with HCV infection. We also performed subgroup and sensitivity analysis. Results: A total of 8 cohort studies involving 1,939,164 participants were included in this meta-analysis. The result from the meta-analysis suggested that there was no statistically significant association between HCV and the risk of developing CRC (HR = 0.99, 95% CI: 0.82-1.88, p = 0.88) with low statistical heterogeneity (I2 = 28%, p = 0.20). Subgroup analyses that were conducted based on study design, diagnosis of HCV infection, and publication year yielded similar results. Analyses of subgroups based on study areas revealed that there was no significant association between HCV infection and CRC risk in Asia (n = 2, HR = 0.96, 95% CI: 0.71-1.29, p = 0.79; I2 = 26%), Europe (n = 3, HR = 1.06, 95% CI: 0.83-1.37, p = 0.63; I2 = 0%), and North America (n = 2, HR = 1.10, 95% CI: 0.87-1.38, p = 0.44; I2 = 0%); however, a negative correlation was found in Oceania (n = 1, HR = 0.43, 95% CI: 0.22-0.84, p = 0.01). Sensitivity analysis further reinforce the stability of our conclusion. Conclusion: Our cohort-based meta-analysis showed insufficient evidence to support the association between HCV infection and an increased risk of CRC. To gain a clearer insight into the potential association between these two conditions, it would be beneficial to conduct large, well-designed, high-quality prospective cohort studies that consider different ethnic populations and potential confounding factors.Systematic review registration: PROSPERO, identifier [CRD42023472688], https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023472688.

8.
Nat Genet ; 56(9): 1975-1984, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39138385

RESUMO

Cultivated peanut (Arachis hypogaea L.) is a widely grown oilseed crop worldwide; however, the events leading to its origin and diversification are not fully understood. Here by combining chloroplast and whole-genome sequence data from a large germplasm collection, we show that the two subspecies of A. hypogaea (hypogaea and fastigiata) likely arose from distinct allopolyploidization and domestication events. Peanut genetic clusters were then differentiated in relation to dissemination routes and breeding efforts. A combination of linkage mapping and genome-wide association studies allowed us to characterize genes and genomic regions related to main peanut morpho-agronomic traits, namely flowering pattern, inner tegument color, growth habit, pod/seed weight and oil content. Together, our findings shed light on the evolutionary history and phenotypic diversification of peanuts and might be of broad interest to plant breeders.


Assuntos
Arachis , Cloroplastos , Evolução Molecular , Genoma de Planta , Estudo de Associação Genômica Ampla , Fenótipo , Sequenciamento Completo do Genoma , Arachis/genética , Cloroplastos/genética , Mapeamento Cromossômico , Filogenia , Domesticação , Melhoramento Vegetal/métodos
9.
Front Cardiovasc Med ; 10: 1291438, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38268853

RESUMO

Background and aims: It is uncertain if there is a link between non-alcoholic fatty liver disease (NAFLD) and cardiovascular diseases (CVD) in young adults and children. To evaluate the potential link between these two conditions, we conducted a systematic review and meta-analysis of cohort studies. Methods: A comprehensive search was conducted in PubMed, Web of Science and Embase in order to locate all relevant cohort studies published until August 2023. Random effects meta-analyses were conducted using the generic inverse variance method, with additional subgroup and sensitivity analyses. The Newcastle-Ottawa Scale was employed to evaluate the methodological quality. Results: Four cohort studies (eleven datasets) involving 10,668,189 participants were included in this meta-analysis. This meta-analysis demonstrated that NAFLD increases the risk of CVD in young adults and children (HR = 1.63, 95% CI: 1.46-1.82, P < 0.00001). Further subgroup analyses showed that individuals with NAFLD were at a heightened risk of coronary heart disease (CHD) (HR = 3.10, 95% CI: 2.01-4.77, P < 0.00001), myocardial infarction (MI) (HR = 1.69, 95% CI: 1.61-1.78, P < 0.00001), atrial fibrillation (AF) (HR = 2.00, 95% CI: 1.12-3.57, P = 0.02), congestive heart failure (CHF) (HR = 3.89, 95% CI: 1.20-12.61, P = 0.02), and stroke (HR = 1.47, 95% CI: 1.39-1.55, P < 0.00001). The results of subgroup analyses based on the study location, NAFLD definition, and follow-up time also showed consistency with the overall results. Sensitivity analyses showed that our results were robust. All of the included studies were judged to be of medium to high quality. Conclusion: Current evidence reveals that NAFLD is linked to an increased risk of major CVD (including CHD, MI, AF, CHF and stroke) in young adults and children. Further research is needed to strengthen this association and provide stronger evidence for primary prevention of CVD in young adults and children with NAFLD. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/, PROSPERO registration number: CRD42023457817.

10.
Sci Rep ; 10(1): 1480, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32001802

RESUMO

Due to their low losses, dielectric metamaterials provide an ideal resolution to construct ultra-narrowband absorbers. To improve the sensing performance, we present numerically a near-infrared ultra-narrowband absorber by putting ultra-sparse dielectric nanowire grids on metal substrate in this paper. The simulation results show that the absorber has an absorption rate larger than 0.99 with full width at half-maximum (FWHM) of 0.38 nm. The simulation field distribution also indicates that the ultra-narrowband absorption is originated from the low loss in the guided-mode resonance. Thanks to the ultra-narrow absorption bandwidths and the electric field mainly distributed out of the ultra-sparse dielectric nanowire grids, our absorber has a high sensitivity S of 1052 nm/RIU and a large figure of merit (FOM) of 2768 which mean that this ultra-narrowband absorber can be applied as a high-performance refractive index sensor.

11.
Mol Med Rep ; 17(3): 3845-3852, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29328416

RESUMO

Postoperative cognitive dysfunction (POCD) is a clinical syndrome characterized by varying degrees of cognitive functional decline in patients following major surgery. Inflammation and a dysregulated innate immune system exert broad effects in the periphery and central nervous system, yet the mechanisms underlying POCD remain poorly understood and without effective therapy. It has been reported that modulation of the dysregulated inflammatory response with low­dose lipopolysaccharide (LPS) preconditioning, a phenomenon additionally referred to as endotoxin tolerance, has the potential to reduce neuroinflammation, blood­brain barrier disruption, and cognitive impairment in a number of disease states. Therefore, it was hypothesized that endotoxin tolerance induced by LPS preconditioning may protect against surgery­induced cognitive impairment in aging mice. Using a mouse model of surgery­induced cognitive decline, the present study demonstrated that exploratory laparotomy caused a significant impairment in hippocampal­dependent memory. Notably, one application of low­dose LPS preconditioning at 24 h prior to surgery improved the cognitive impairment and abolished the signs of neuroinflammation in the hippocampus following surgery. However, LPS injection at 6 h or immediately prior to surgery did not confer such beneficial effects, suggesting that the effects of LPS­induced endotoxin tolerance may depend on the time of application. In conclusion, the results of the present study suggested that low­dose LPS preconditioning may markedly alleviate surgery­induced neuroinflammation and cognitive impairment in aging mice, which may provide a novel approach to preventing POCD and, potentially, other forms of memory impairment.


Assuntos
Envelhecimento/psicologia , Disfunção Cognitiva/prevenção & controle , Tolerância a Medicamentos/imunologia , Hipocampo/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Complicações Pós-Operatórias/psicologia , Envelhecimento/imunologia , Animais , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/imunologia , Disfunção Cognitiva/psicologia , Modelos Animais de Doenças , Hipocampo/imunologia , Hipocampo/fisiopatologia , Laparoscopia/efeitos adversos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Complicações Pós-Operatórias/imunologia , Complicações Pós-Operatórias/fisiopatologia , Fatores de Proteção , Fatores de Tempo
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